The Williams-Steiger Occupational Safety and Health Act of 1970 (84 Stat. 1590 et seq., 29 U.S.C. 651 et seq. ) requires, in part, that every employer covered under the Act furnish to his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees. The Act also requires that employers comply with occupational safety and health standards promulgated under the Act, and that employees comply with standards, rules, regulations and orders issued under the Act which are applicable to their own actions and conduct. The Act authorizes the Department of Labor to conduct inspections, and to issue citations and proposed penalties for alleged violations. The Act, under section 20(b), also authorizes the Secretary of Health, Education, and Welfare to conduct inspections and to question employers and employees in connection with research and other related activities. The Act contains provisions for adjudication of violations, periods prescribed for the abatement of violations, and proposed penalties by the Occupational Safety and Health Review Commission, if contested by an employer or by an employee or authorized representative of employees, and for judicial review. The purpose of this part 1903 is to prescribe rules and to set forth general policies for enforcement of the inspection, citation, and proposed penalty provisions of the Act. In situations where this part 1903 sets forth general enforcement policies rather than substantive or procedural rules, such policies may be modified in specific circumstances where the Secretary or his designee determines that an alternative course of action would better serve the objectives of the Act.
[36 FR 17850, Sept. 4, 1971, as amended at 39 FR 39036, Nov. 5, 1974; 80 FR 49904, Aug. 18, 2015; 81 FR 43452, July 1, 2016]
[45 FR 65923, Oct. 3, 1980]
Any permission to enter, inspect, review records, or question any person, shal not imply or be conditioned upon a waiver of any cause of action, citation, or penalty under the Act. Compliance Safety and Health Officers are not authorized to grant any such waiver.
[36 FR 17850, Sept. 4, 1971, as amended at 81 FR 43452, July 1, 2016]
[36 FR 17850, Sept. 14, 1971, as amended at 47 FR 6533, Feb. 12, 1982; 47 FR 55481, Dec. 10, 1982]
[36 FR 17850, Sept. 4, 1971, as amended at 89 FR 22601, Apr. 1, 2024]
“All information reported to or otherwise obtained by the Secretary or his representative in connection with any inspection or proceeding under this Act which contains or which might reveal a trade secret referred to in section 1905 of title 18 of the United States Code shall be considered confidential for the purpose of that section, except that such information may be disclosed to other officers or employees concerned with carrying out this Act or when relevant in any proceeding under this Act. In any such proceeding the Secretary, the Commission, or the court shall issue such orders as may be appropriate to protect the confidentiality of trade secrets.” Section 15 of the Act is considered a statute within the meaning of section 552(b)(3) of title 5 of the United States Code, which exempts from the disclosure requirements matters that are “specifically exempted from disclosure by statute.”
Compliance Safety and Health Officers may consult with employees concerning matters of occupational safety and health to the extent they deem necessary for the conduct of an effective and thorough inspection. During the course of an inspection, any employee shall be afforded an opportunity to bring any violation of the Act which he has reason to believe exists in the workplace to the attention of the Compliance Safety and Health Officer.
“No person shall discharge or in any manner discriminate against any employee because such employee has filed any complaint or instituted or caused to be instituted any proceeding under or related to this Act or has testified or is about to testify in any such proceeding or because of the exercise by such employee on behalf of himself or others of any right afforded by this Act.”
[36 FR 17850, Sept. 4, 1973, as amended at 54 FR 24333, June 7, 1989]
Whenever and as soon as a Compliance Safety and Health Officer concludes on the basis of an inspection that conditions or practices exist in any place of employment which could reasonably be expected to cause death or serious physical harm immediately or before the imminence of such danger can be eliminated through the enforcement procedures otherwise provided by the Act, he shall inform the affected employees and employers of the danger and that he is recommending a civil action to restrain such conditions or practices and for other appropriate relief in accordance with the provisions of section 13(a) of the Act. Appropriate citations and notices of proposed penalties may be issued with respect to an imminent danger even though, after being informed of such danger by the Compliance Safety and Health Officer, the employer immediately eliminates the imminence of the danger and initiates steps to abate such danger.
[36 FR 17850, Sept. 4, 1971, as amended at 59 FR 66613, Dec. 27, 1994]
[40 FR 6334, Feb. 11, 1975; 40 FR 11351, Mar. 11, 1975]
The adjusted civil penalties for penalties proposed after January 15, 2025 are as follows:
The penalty per willful violation under section 17(a) of the Act, 29 U.S.C. 666(a), shall not be less than $11,823 and shall not exceed $165,514.
The penalty per repeated violation under section 17(a) of the Act, 29 U.S.C. 666(a), shall not exceed $165,514.
The penalty for a serious violation under section 17(b) of the Act, 29 U.S.C. 666(b), shall not exceed $16,550.
The penalty for an other-than-serious violation under section 17(c) of the Act, 29 U.S.C. 666(c), shall not exceed $16,550.
The penalty for a failure to correct a violation under section 17(d) of the Act, 29 U.S.C. 666(d), shall not exceed $16,550 per day.
The penalty for a posting requirement violation under section 17(i) of the Act, 29 U.S.C. 666(i), shall not exceed $16,550.
[36 FR 17850, Sept. 4, 1971, as amended at 81 FR 43453, July 1, 2016; 82 FR 5382, Jan. 18, 2017; 83 FR 14, Jan. 2, 2018; 84 FR 219, Jan. 23, 2019; 85 FR 2298, Jan. 15, 2020; 86 FR 2969, Jan. 14, 2021; 87 FR 2336, Jan. 14, 2022; 88 FR 2217, Jan. 13, 2023; 89 FR 1817, Jan. 11, 2024; 90 FR 1861, Jan. 10, 2025]
[36 FR 17850, Sept. 4, 1971, as amended at 81 FR 43453, July 1, 2016]
[36 FR 17850, Sept. 4, 1971, as amended at 81 FR 43453, July 1, 2016]
Purpose. OSHA's inspections are intended to result in the abatement of violations of the Occupational Safety and Health Act of 1970 (the OSH Act). This section sets forth the procedures OSHA will use to ensure abatement. These procedures are tailored to the nature of the violation and the employer's abatement actions.
This section applies to employers who receive a citation for a violation of the Occupational Safety and Health Act.
Appendix A to Section 1903.19—Sample Abatement-Certification Letter (Nonmandatory)
U. S. Department of Labor—OSHA
Address of the Area Office (on the citation)
[Company's Name]
[Company's Address]
The hazard referenced in Inspection Number [insert 9-digit #] for violation identified as:
Citation [insert #] and item [insert #] was corrected on [insert date] by:
Citation [insert #] and item [insert #] was corrected on [insert date] by:
Citation [insert #] and item [insert #] was corrected on [insert date] by:
Citation [insert #] and item [insert #] was corrected on [insert date] by:
Citation [insert #] and item [insert #] was corrected on [insert date] by:
Citation [insert #] and item [insert #] was corrected on [insert date] by:
Citation [insert #] and item [insert #] was corrected on insert date by:
Citation [insert #] and item [insert #] was corrected on [insert date] by:
I attest that the information contained in this document is accurate.
Signature
Typed or Printed Name
Appendix B to Section 1903.19—Sample Abatement Plan or Progress Report (Nonmandatory)
U. S. Department of Labor—OSHA
Address of Area Office (on the citation)
[Company's Name]
[Company's Address]
Check one:
Abatement Plan [ ]
Progress Report [ ]
Inspection Number
Page __ of ____
Citation Number(s)*
Item Number(s)*
| Action | Proposed Completion Date (for abatement plans only) | Completion Date (for progress reports only) |
|---|---|---|
| 1. | ||
| 2. | ||
| 3. | ||
| 4. | ||
| 5. | ||
| 6. | ||
| 7. |
Date required for final abatement:
I attest that the information contained in this document is accurate.
Signature
Typed or Printed Name
Name of primary point of contact for questions: [optional]
Telephone number:
*Abatement plans or progress reports for more than one citation item may be combined in a single abatement plan or progress report if the abatement actions, proposed completion dates, and actual completion dates (for progress reports only) are the same for each of the citation items.
At the request of an affected employer, employee, or representative of employees, the Assistant Regional Director may hold an informal conference for the purpose of discussing any issues raised by an inspection, citation, notice of proposed penalty, or notice of intention to contest. The settlement of any issue at such conference shall be subject to the rules of procedure prescribed by the Review Commission. If the conference is requested by the employer, an affected employee or his representative shall be afforded an opportunity to participate, at the discretion of the Assistant Regional Director. If the conference is requested by an employee or representative of employees, the employer shall be afforded an opportunity to participate, at the discretion of the Assistant Regional Director. Any party may be represented by counsel at such conference. No such conference or request for such conference shall operate as a stay of any 15-working-day period for filing a notice of intention to contest as prescribed in § 1903.17.
[36 FR 17850, Sept. 4, 1971. Redesignated at 62 FR 15337, Mar. 31, 1997]
Nothing in this part 1903 shall preempt the authority of any State to conduct inspections, to initiate enforcement proceedings or otherwise to implement the applicable provisions of State law with respect to State occupational safety and health standards in accordance with agreements and plans under section 18 of the Act and parts 1901 and 1902 of this chapter.
[36 FR 17850, Sept. 4, 1971. Redesignated at 62 FR 15337, Mar. 31, 1997]
[36 FR 17850, Sept. 4, 1971, as amended at 38 FR 22624, Aug. 23, 1973. Redesignated at 62 FR 15337, Mar. 31, 1997]
The purpose of this rule (part 1904) is to require employers to record and report work-related fatalities, injuries, and illnesses.
[82 FR 20548, May 3, 2017]
[66 FR 6122, Jan. 19, 2001, as amended at 85 FR 8731, Feb. 18, 2020]
[66 FR 6122, Jan. 19, 2001, as amended at 79 FR 56186, Sept. 18, 2014]
If you create records to comply with another government agency's injury and illness recordkeeping requirements, OSHA will consider those records as meeting OSHA's part 1904 recordkeeping requirements if OSHA accepts the other agency's records under a memorandum of understanding with that agency, or if the other agency's records contain the same information as this part 1904 requires you to record. You may contact your nearest OSHA office or State agency for help in determining whether your records meet OSHA's requirements.
Employers are not required to keep OSHA injury and illness records for any establishment classified in the following North American Industry Classification System (NAICS) codes, unless they are asked in writing to do so by OSHA, the Bureau of Labor Statistics (BLS), or a state agency operating under the authority of OSHA or the BLS. All employers, including those partially exempted by reason of company size or industry classification, must report to OSHA any employee's fatality, in-patient hospitalization, amputation, or loss of an eye (see § 1904.39).
| NAICS Code | Industry |
|---|---|
| 4412 | Other Motor Vehicle Dealers. |
| 4431 | Electronics and Appliance Stores. |
| 4461 | Health and Personal Care Stores. |
| 4471 | Gasoline Stations. |
| 4481 | Clothing Stores. |
| 4482 | Shoe Stores. |
| 4483 | Jewelry, Luggage, and Leather Goods Stores. |
| 4511 | Sporting Goods, Hobby, and Musical Instrument Stores. |
| 4512 | Book, Periodical, and Music Stores. |
| 4531 | Florists. |
| 4532 | Office Supplies, Stationery, and Gift Stores. |
| 4812 | Nonscheduled Air Transportation. |
| 4861 | Pipeline Transportation of Crude Oil. |
| 4862 | Pipeline Transportation of Natural Gas. |
| 4869 | Other Pipeline Transportation. |
| 4879 | Scenic and Sightseeing Transportation, Other. |
| 4885 | Freight Transportation Arrangement. |
| 5111 | Newspaper, Periodical, Book, and Directory Publishers. |
| 5112 | Software Publishers. |
| 5121 | Motion Picture and Video Industries. |
| 5122 | Sound Recording Industries. |
| 5151 | Radio and Television Broadcasting. |
| 5172 | Wireless Telecommunications Carriers (except Satellite). |
| 5173 | Telecommunications Resellers. |
| 5179 | Other Telecommunications. |
| 5181 | Internet Service Providers and Web Search Portals. |
| 5182 | Data Processing, Hosting, and Related Services. |
| 5191 | Other Information Services. |
| 5211 | Monetary Authorities—Central Bank. |
| 5221 | Depository Credit Intermediation. |
| 5222 | Nondepository Credit Intermediation. |
| 5223 | Activities Related to Credit Intermediation. |
| 5231 | Securities and Commodity Contracts Intermediation and Brokerage. |
| 5232 | Securities and Commodity Exchanges. |
| 5239 | Other Financial Investment Activities. |
| 5241 | Insurance Carriers. |
| 5242 | Agencies, Brokerages, and Other Insurance Related Activities. |
| 5251 | Insurance and Employee Benefit Funds. |
| 5259 | Other Investment Pools and Funds. |
| 5312 | Offices of Real Estate Agents and Brokers. |
| 5331 | Lessors of Nonfinancial Intangible Assets (except Copyrighted Works). |
| 5411 | Legal Services. |
| 5412 | Accounting, Tax Preparation, Bookkeeping, and Payroll Services. |
| 5413 | Architectural, Engineering, and Related Services. |
| 5414 | Specialized Design Services. |
| 5415 | Computer Systems Design and Related Services. |
| 5416 | Management, Scientific, and Technical Consulting Services. |
| 5417 | Scientific Research and Development Services. |
| 5418 | Advertising and Related Services. |
| 5511 | Management of Companies and Enterprises. |
| 5611 | Office Administrative Services. |
| 5614 | Business Support Services. |
| 5615 | Travel Arrangement and Reservation Services. |
| 5616 | Investigation and Security Services. |
| 6111 | Elementary and Secondary Schools. |
| 6112 | Junior Colleges. |
| 6113 | Colleges, Universities, and Professional Schools. |
| 6114 | Business Schools and Computer and Management Training. |
| 6115 | Technical and Trade Schools. |
| 6116 | Other Schools and Instruction. |
| 6117 | Educational Support Services. |
| 6211 | Offices of Physicians. |
| 6212 | Offices of Dentists. |
| 6213 | Offices of Other Health Practitioners. |
| 6214 | Outpatient Care Centers. |
| 6215 | Medical and Diagnostic Laboratories. |
| 6244 | Child Day Care Services. |
| 7114 | Agents and Managers for Artists, Athletes, Entertainers, and Other Public Figures. |
| 7115 | Independent Artists, Writers, and Performers. |
| 7213 | Rooming and Boarding Houses. |
| 7221 | Full-Service Restaurants. |
| 7222 | Limited-Service Eating Places. |
| 7224 | Drinking Places (Alcoholic Beverages). |
| 8112 | Electronic and Precision Equipment Repair and Maintenance. |
| 8114 | Personal and Household Goods Repair and Maintenance. |
| 8121 | Personal Care Services. |
| 8122 | Death Care Services. |
| 8131 | Religious Organizations. |
| 8132 | Grantmaking and Giving Services. |
| 8133 | Social Advocacy Organizations. |
| 8134 | Civic and Social Organizations. |
| 8139 | Business, Professional, Labor, Political, and Similar Organizations. |
[79 FR 56186, Sept. 18, 2014]
Each employer required by this part to keep records of fatalities, injuries, and illnesses must record each fatality, injury and illness that:
See § 1904.5.
See § 1904.6.
See § 1904.7.
[66 FR 6122, Jan. 19, 2001, as amended at 81 FR 91809, Dec. 19, 2016; 82 FR 20548, May 3, 2017]
You must consider an injury or illness to be work-related if an event or exposure in the work environment either caused or contributed to the resulting condition or significantly aggravated a pre-existing injury or illness. Work-relatedness is presumed for injuries and illnesses resulting from events or exposures occurring in the work environment, unless an exception in § 1904.5(b)(2) specifically applies.
| 1904.5(b)(2) | You are not required to record injuries and illnesses if . . . |
|---|---|
| (i) | At the time of the injury or illness, the employee was present in the work environment as a member of the general public rather than as an employee. |
| (ii) | The injury or illness involves signs or symptoms that surface at work but result solely from a non-work-related event or exposure that occurs outside the work environment. |
| (iii) | The injury or illness results solely from voluntary participation in a wellness program or in a medical, fitness, or recreational activity such as blood donation, physical examination, flu shot, exercise class, racquetball, or baseball. |
| (iv) | The injury or illness is solely the result of an employee eating, drinking, or preparing food or drink for personal consumption (whether bought on the employer's premises or brought in). For example, if the employee is injured by choking on a sandwich while in the employer's establishment, the case would not be considered work-related. |
| Note: If the employee is made ill by ingesting food contaminated by workplace contaminants (such as lead), or gets food poisoning from food supplied by the employer, the case would be considered work-related. | |
| (v) | The injury or illness is solely the result of an employee doing personal tasks (unrelated to their employment) at the establishment outside of the employee's assigned working hours. |
| (vi) | The injury or illness is solely the result of personal grooming, self medication for a non-work-related condition, or is intentionally self-inflicted. |
| (vii) | The injury or illness is caused by a motor vehicle accident and occurs on a company parking lot or company access road while the employee is commuting to or from work. |
| (viii) | The illness is the common cold or flu (Note: contagious diseases such as tuberculosis, brucellosis, hepatitis A, or plague are considered work-related if the employee is infected at work). |
| (ix) | The illness is a mental illness. Mental illness will not be considered work-related unless the employee voluntarily provides the employer with an opinion from a physician or other licensed health care professional with appropriate training and experience (psychiatrist, psychologist, psychiatric nurse practitioner, etc.) stating that the employee has a mental illness that is work-related. |
Injuries or illnesses that occur when the employee is on travel status do not have to be recorded if they meet one of the exceptions listed below.
| 1904.5 (b)(6) | If the employee has . . . | You may use the following to determine if an injury or illness is work-related |
|---|---|---|
| (i) | checked into a hotel or motel for one or more days | When a traveling employee checks into a hotel, motel, or into an other temporary residence, he or she establishes a “home away from home.” You must evaluate the employee's activities after he or she checks into the hotel, motel, or other temporary residence for their work-relatedness in the same manner as you evaluate the activities of a non-traveling employee. When the employee checks into the temporary residence, he or she is considered to have left the work environment. When the employee begins work each day, he or she re-enters the work environment. If the employee has established a “home away from home” and is reporting to a fixed worksite each day, you also do not consider injuries or illnesses work-related if they occur while the employee is commuting between the temporary residence and the job location. |
| (ii) | taken a detour for personal reasons | Injuries or illnesses are not considered work-related if they occur while the employee is on a personal detour from a reasonably direct route of travel ( e.g., has taken a side trip for personal reasons). |
You must consider an injury or illness to be a “new case” if:
You must consider an injury or illness to meet the general recording criteria, and therefore to be recordable, if it results in any of the following: death, days away from work, restricted work or transfer to another job, medical treatment beyond first aid, or loss of consciousness. You must also consider a case to meet the general recording criteria if it involves a significant injury or illness diagnosed by a physician or other licensed health care professional, even if it does not result in death, days away from work, restricted work or job transfer, medical treatment beyond first aid, or loss of consciousness.
See § 1904.7(b)(2).
See § 1904.7(b)(3).
See § 1904.7(b)(4).
See § 1904.7(b)(5).
See § 1904.7(b)(6).
You must record all work-related needlestick injuries and cuts from sharp objects that are contaminated with another person's blood or other potentially infectious material (as defined by 29 CFR 1910.1030). You must enter the case on the OSHA 300 Log as an injury. To protect the employee's privacy, you may not enter the employee's name on the OSHA 300 Log (see the requirements for privacy cases in paragraphs 1904.29(b)(6) through 1904.29(b)(9)).
If an employee is medically removed under the medical surveillance requirements of an OSHA standard, you must record the case on the OSHA 300 Log.
If an employee's hearing test (audiogram) reveals that the employee has experienced a work-related Standard Threshold Shift (STS) in hearing in one or both ears, and the employee's total hearing level is 25 decibels (dB) or more above audiometric zero (averaged at 2000, 3000, and 4000 Hz) in the same ear(s) as the STS, you must record the case on the OSHA 300 Log.
If the employee has never previously experienced a recordable hearing loss, you must compare the employee's current audiogram with that employee's baseline audiogram. If the employee has previously experienced a recordable hearing loss, you must compare the employee's current audiogram with the employee's revised baseline audiogram (the audiogram reflecting the employee's previous recordable hearing loss case).
Audiometric test results reflect the employee's overall hearing ability in comparison to audiometric zero. Therefore, using the employee's current audiogram, you must use the average hearing level at 2000, 3000, and 4000 Hz to determine whether or not the employee's total hearing level is 25 dB or more.
[67 FR 44047, July 1, 2002, as amended at 67 FR 77170, Dec. 17, 2002; 84 FR 21457, May 14, 2019]
If any of your employees has been occupationally exposed to anyone with a known case of active tuberculosis (TB), and that employee subsequently develops a tuberculosis infection, as evidenced by a positive skin test or diagnosis by a physician or other licensed health care professional, you must record the case on the OSHA 300 Log by checking the “respiratory condition” column.
You must use OSHA 300, 300-A, and 301 forms, or equivalent forms, for recordable injuries and illnesses. The OSHA 300 form is called the Log of Work-Related Injuries and Illnesses, the 300-A is the Summary of Work-Related Injuries and Illnesses, and the OSHA 301 form is called the Injury and Illness Incident Report.
infection, hepatitis, or tuberculosis;
[66 FR 6122, Jan. 19, 2001, as amended at 66 FR 52034, Oct. 12, 2001; 67 FR 77170, Dec. 17, 2002; 68 FR 38607, June 30, 2003; 81 FR 91809, Dec. 19, 2016; 82 FR 20548, May 3, 2017]
You must keep a separate OSHA 300 Log for each establishment that is expected to be in operation for one year or longer.
You must record on the OSHA 300 Log the recordable injuries and illnesses of all employees on your payroll, whether they are labor, executive, hourly, salary, part-time, seasonal, or migrant workers. You also must record the recordable injuries and illnesses that occur to employees who are not on your payroll if you supervise these employees on a day-to-day basis. If your business is organized as a sole proprietorship or partnership, the owner or partners are not considered employees for recordkeeping purposes.
At the end of each calendar year, you must:
[66 FR 6122, Jan. 19, 2001, as amended at 81 FR 91810, Dec. 19, 2016; 82 FR 20548, May 3, 2017; 85 FR 8731, Feb. 18, 2020]
You must save the OSHA 300 Log, the privacy case list (if one exists), the annual summary, and the OSHA 301 Incident Report forms for five (5) years following the end of the calendar year that these records cover.
[66 FR 6122, Jan. 19, 2001, as amended at 81 FR 91810, Dec. 19, 2016; 82 FR 20548, May 3, 2017]
If your business changes ownership, you are responsible for recording and reporting work-related injuries and illnesses only for that period of the year during which you owned the establishment. You must transfer the part 1904 records to the new owner. The new owner must save all records of the establishment kept by the prior owner, as required by § 1904.33 of this part, but need not update or correct the records of the prior owner.
[82 FR 20549, May 3, 2017]
Your employees and their representatives must be involved in the recordkeeping system in several ways.
[81 FR 29691, May 12, 2016; 81 FR 31854, May 20, 2016, as amended at 81 FR 91810, Dec. 19, 2016; 82 FR 20549, May 3, 2017]
In addition to § 1904.35, section 11(c) of the OSH Act also prohibits you from discriminating against an employee for reporting a work-related fatality, injury, or illness. That provision of the Act also protects the employee who files a safety and health complaint, asks for access to the part 1904 records, or otherwise exercises any rights afforded by the OSH Act.
[81 FR 29692, May 12, 2016]
Some States operate their own OSHA programs, under the authority of a State plan as approved by OSHA. States operating OSHA-approved State plans must have occupational injury and illness recording and reporting requirements that are substantially identical to the requirements in this part (see 29 CFR 1902.3(j), 29 CFR 1902.7, and 29 CFR 1956.10(i)).
[66 FR 6122, Jan. 19, 2001, as amended at 80 FR 49904, Aug. 18, 2015]
If you wish to keep records in a different manner from the manner prescribed by the part 1904 regulations, you may submit a variance petition to the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, Washington, DC 20210. You can obtain a variance only if you can show that your alternative recordkeeping system:
, fatality, in-patient hospitalization, amputation, or loss of an eye);
[79 FR 56187, Sept. 18, 2014]
When an authorized government representative asks for the records you keep under part 1904, you must provide copies of the records within four (4) business hours.
[66 FR 6122, Jan. 19, 2001, as amended at 81 FR 91810, Dec. 19, 2016; 82 FR 20549, May 3, 2017]
Upon notification, you must electronically submit the requested information from your part 1904 records to OSHA or OSHA's designee.
For each establishment that is subject to these reporting requirements, you must provide the EIN used by the establishment.
Employee name (field 1), employee address (field 2), name of physician or other health care professional (field 6), facility name and address if treatment was given away from the worksite (field 7).
Establishments that are required to submit under paragraph (a)(1) or (2) of this section must submit all of the required information by March 2 of the year after the calendar year covered by the form(s) (for example, by March 2, 2024, for the forms covering 2023).
[81 FR 29692, May 12, 2016, as amended at 82 FR 55765, Nov. 24, 2017; 84 FR 405, Jan. 25, 2019; 88 FR 47346, July 21, 2023]
If you receive a Survey of Occupational Injuries and Illnesses Form from the Bureau of Labor Statistics (BLS), or a BLS designee, you must promptly complete the form and return it following the instructions contained on the survey form.
If you were required to keep OSHA 200 Logs in 2001, you must post a 2000 annual summary from the OSHA 200 Log of occupational injuries and illnesses for each establishment.
You must save your copies of the OSHA 200 and 101 forms for five years following the year to which they relate and continue to provide access to the data as though these forms were the OSHA 300 and 301 forms. You are not required to update your old 200 and 101 forms.
The following sections each contain a collection of information requirement which has been approved by the Office of Management and Budget under the control number listed
| 29 CFR citation | OMB Control No. |
|---|---|
| 1904.4-35 | 1218-0176 |
| 1904.39-41 | 1218-0176 |
| 1904.42 | 1220-0045 |
| 1904.43-44 | 1218-0176 |
The Act. The Act means the Occupational Safety and Health Act of 1970 (29 U.S.C. 651 et seq. ). The definitions contained in section 3 of the Act (29 U.S.C. 652) and related interpretations apply to such terms when used in this part 1904.
Establishment. An establishment is a single physical location where business is conducted or where services or industrial operations are performed. For activities where employees do not work at a single physical location, such as construction; transportation; communications, electric, gas and sanitary services; and similar operations, the establishment is represented by main or branch offices, terminals, stations, etc. that either supervise such activities or are the base from which personnel carry out these activities.
Injury or illness. An injury or illness is an abnormal condition or disorder. Injuries include cases such as, but not limited to, a cut, fracture, sprain, or amputation. Illnesses include both acute and chronic illnesses, such as, but not limited to, a skin disease, respiratory disorder, or poisoning. (Note: Injuries and illnesses are recordable only if they are new, work-related cases that meet one or more of the part 1904 recording criteria.)
Physician or Other Licensed Health Care Professional. A physician or other licensed health care professional is an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently perform, or be delegated the responsibility to perform, the activities described by this regulation.
You. “You” means an employer as defined in section 3 of the Occupational Safety and Health Act of 1970 (29 U.S.C. 652).
[66 FR 6122, Jan. 19, 2001, as amended at 85 FR 8731, Feb. 18, 2020]
As used in this part, unless the context clearly requires otherwise:
[39 FR 23502, June 27, 1974, as amended at 58 FR 35308, June 30, 1993; 85 FR 8732, Feb. 18, 2020]
Government, and organizations which are not agencies of the U.S. Government which are incorporated by reference in this part, have the same force and effect as other standards in this part. Only the mandatory provisions ( i.e., provisions containing the word “shall” or other mandatory language) of standards incorporated by reference are adopted as standards under the Occupational Safety and Health Act.
A Manual of Recommended Practice” (22nd ed., 1995), incorporation by reference (IBR) approved for § 1910.124(b)(4)(iii).
Emblem for Identifying Slow Moving Vehicles, ASAE S276.2 (1968), IBR approved for § 1910.145(d)(10).
Specifications for Anhydrous Ammonia Hose, IBR approved for § 1910.111(b)(8)(i).
A11.1-65 (R 70) Practice for Industrial Lighting, IBR approved for §§ 1910.219(c)(5)(iii); 1910.261 (a)(3)(i), (c)(10), and (k)(21); and 1910.265(c)(2).
A11.1-65 Practice for Industrial Lighting, IBR approved for §§ 1910.262(c)(6) and 1910.265(d)(2)(i)(a).
A13.1-56 Scheme for the Identification of Piping Systems, IBR approved for §§ 1910.253(d)(4)(ii); 1910.261(a)(3)(iii); 1910.262(c)(7).
A14.1-68 Safety Code for Portable Wood Ladders, Supplemented by ANSI A14.1a-77, IBR approved for § 1910.261 (a)(3)(iv) and (c)(3)(i).
A14.2-56 Safety Code for Portable Metal Ladders, Supplemented by ANSI A14.2a-77, IBR approved for § 1910.261 (a)(3)(v) and (c)(3)(i).
A14.3-56 Safety Code for Fixed Ladders, IBR approved for §§ 1910.68(b)(4); and 1910.261 (a)(3)(vi) and (c)(3)(i).
A17.1-65 Safety Code for Elevators, Dumbwaiters and Moving Walks, Including Supplements, A17.1a (1967); A17.1b (1968); A17.1c (1969); A17.1d (1970), IBR approved for § 1910.261 (a)(3)(vii), (g)(11)(i), and (l)(4).
A17.2-60 Practice for the Inspection of Elevators, Including Supplements, A17.2a (1965), A17.2b (1967), IBR approved for § 1910.261(a)(3)(viii).
A90.1-69 Safety Standard for Manlifts, IBR approved for § 1910.68(b)(3).
A92.2-69 Standard for Vehicle Mounted Elevating and Rotating Work Platforms, IBR approved for § 1910.67 (b)(1), (2), (c)(3), and (4) and 1910.268(s)(1)(v).
A120.1-70 Safety Code for Powered Platforms for Exterior Building Maintenance, IBR approved for § 1910.66 app. D (b) through (d).
B7.1-70 Safety Code for the Use, Care and Protection of Abrasive Wheels, IBR approved for §§ 1910.215(b)(12) and 1910.218(j).
B15.1-53 (R 58) Safety Code for Mechanical Power Transmission Apparatus, IBR approved for §§ 1910.68(b)(4) and 1910.261 (a)(3)(ix), (b)(1), (e)(3), (e)(9), (f)(4), (j)(5)(iv), (k)(12), and (l)(3).
B20.1-57 Safety Code for Conveyors, Cableways, and Related Equipment, IBR approved for §§ 1910.218(j)(3); 1910.261 (a)(3)(x), (b)(1), (c)(15)(iv), (f)(4), and (j)(2); 1910.265(c)(18)(i).
B30.2-43 (R 52) Safety Code for Cranes, Derricks, and Hoists, IBR approved for § 1910.261 (a)(3)(xi), (c)(2)(vi), and (c)(8) (i) and (iv).
B30.2.0-67 Safety Code for Overhead and Gantry Cranes, IBR approved for §§ 1910.179(b)(2); 1910.261 (a)(3)(xii), (c)(2)(v), and (c)(8) (i) and (iv).
B30.5-68 Safety Code for Crawler, Locomotive, and Truck Cranes, IBR approved for §§ 1910.180(b)(2) and 1910.261(a)(3)(xiii).
B30.6-69 Safety Code for Derricks, IBR approved for §§ 1910.181(b)(2) and 1910.268(j)(4)(iv) (E) and (H).
B31.1-55 Code for Pressure Piping, IBR approved for § 1910.261(g)(18)(iii).
B31.1-67, IBR approved for § 1910.253(d)(1)(i)(A)
B31.1a-63 Addenda to ANSI B31.1 (1955), IBR approved for § 1910.261(g)(18)(iii).
B31.1-67 and Addenda B31.1 (1969) Code for Pressure Piping, IBR approved for §§ 1910.103(b)(1)(iii)(b); 1910.104(b)(5)(ii); 1910.218 (d)(4) and (e)(1)(iv); and 1910.261 (a)(3)(xiv) and (g)(18)(iii).
B31.2-68 Fuel Gas Piping, IBR approved for § 1910.261(g)(18)(iii).
B31.3-66 Petroleum Refinery Piping, IBR approved for § 1910.103(b)(3)(v)(b).
B31.5-66 Addenda B31.5a (1968) Refrigeration Piping, IB approved for §§ 1910.103(b)(3)(v)(b) and 1910.111(b)(7)(iii).
B56.1-69 Safety Standard for Powered Industrial Trucks, IBR approved for §§ 1910.178(a) (2) and (3) and 1910.261 (a)(3)(xv), (b)(6), (m)(2), and (m)(5)(iii).
B57.1-65 Compressed Gas Cylinder Valve Outlet and Inlet Connections, IBR approved for § 1910.253(b)(1)(iii).
B175.1-1991, Safety Requirements for Gasoline-Powered Chain Saws 1910.266(e)(2)(i).
C33.2-56 Safety Standard for Transformer-Type Arc Welding Machines, IBR approved for § 1910.254(b)(1).
H23.1-70 Seamless Copper Water Tube Specification, IBR approved for § 1910.110(b) (8)(ii) and (13)(ii)(b)(1).
H38.7-69 Specification for Aluminum Alloy Seamless Pipe and Seamless Extruded Tube, IBR approved for § 1910.110(b)(8)(i).
J6.4-71 Standard Specification for Rubber Insulating Blankets, IBR approved for § 1910.268 (f)(1) and (n)(11)(v).
J6.6-71 Standard Specification for Rubber Insulating Gloves, IBR approved for § 1910.268 (f)(1) and (n)(11)(iv).
K13.1-67 Identification of Gas Mask Canisters, IBR approved for § 1910.261 (a)(3)(xvi) and (h)(2)(iii).
K61.1-60 Safety Requirements for the Storage and Handling of Anhydrous Ammonia, IBR approved for § 1910.111(b)(11)(i).
K61.1-66 Safety Requirements for the Storage and Handling of Anhydrous Ammonia, IBR approved for § 1910.111(b)(11)(i).
O1.1-54 (R 61) Safety Code for Woodworking Machinery, IBR approved for § 1910.261 (a)(3)(xvii), (e)(7), and (i)(2).
S1.4-71 (R 76) Specification for Sound Level Meters, IBR approved for § 1910.95 appendixes D and I.
S1.11-71 (R 76) Specification for Octave, Half-Octave and Third-Octave Band Filter Sets, IBR approved for § 1910.95 appendix D.
S3.6-69 Specifications for Audiometers, IBR approved for § 1910.95(h)(2) and (5)(ii) and appendix D.
Z4.1-68 Requirements for Sanitation in Places of Employment, IBR approved for § 1910.261 (a)(3)(xviii) and (g)(15)(vi).
Z9.1-51 Safety Code for Ventilation and Operation of Open Surface Tanks, IBR approved for 1910.261(a)(3)(xix), (g)(18)(v), and (h)(2)(i).
Z9.1-71 Practices for Ventilation and Operation of Open-Surface Tanks, IBR approved for § 1910.124(b)(4)(iv).
Z9.2-60 Fundamentals Governing the Design and Operation of Local Exhaust Systems, IBR approved for §§ 1910.94(a)(4)(i) introductory text, (a)(6) introductory text, (b)(3)(ix), (b)(4)(i) and (ii), (c)(3)(i) introductory text, (c)(5)(iii)(b), and (c)(7)(iv)(a); 1910.261(a)(3)(xx), (g)(1)(i) and (iii), and (h)(2)(ii).
Z9.2-79 Fundamentals Governing the Design and Operation of Local Exhaust Systems, IBR approved for § 1910.124(b)(4)(i).
Z12.12-68 Standard for the Prevention of Sulfur Fires and Explosions, IBR approved for § 1910.261 (a)(3)(xxi), (d)(1)(i), (f)(2)(iv), and (g)(1)(i).
Z12.20-62 (R 69) Code for the Prevention of Dust Explosions in Woodworking and Wood Flour Manufacturing Plants, IBR approved for § 1910.265(c)(20)(i).
Z21.30-64 Requirements for Gas Appliances and Gas Piping Installations, IBR approved for § 1910.265(c)(15).
Z24.22-57 Method of Measurement of Real-Ear Attenuation of Ear Protectors at Threshold, IBR approved for § 1910.261(a)(3)(xxii).
Z33.1-61 Installation of Blower and Exhaust Systems for Dust, Stock, and Vapor Removal or Conveying, IBR approved for §§ 1910.94(a)(4)(i); 1910.261 (a)(3)(xxiii) and (f)(5); and 1910.265(c)(20)(i).
Z33.1-66 Installation of Blower and Exhaust Systems for Dust, Stock, and Vapor Removal or Conveying, IBR approved for § 1910.94(a)(2)(ii).
Z35.1-1968, Specifications for Accident Prevention Signs; IBR approved for § 1910.261(c). Copies available for purchase from the IHS Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 1-877-413-5184; Web site: www.global.ihs.com.
American National Standard for Personal Protection—Protective Footwear; IBR approved for § 1910.136(b)(1)(ii). Copies of ANSI Z41-1999 are available for purchase only from the National Safety Council, P.O. Box 558, Itasca, IL 60143-0558; telephone: 1-800-621-7619; fax: 708-285-0797; Web site: http://www.nsc.org.
American National Standard for Personal Protection—Protective Footwear; IBR approved for § 1910.136(b)(1)(iii). Copies of ANSI Z41-1991 are available for purchase only from the National Safety Council, P.O. Box 558, Itasca, IL 60143-0558; telephone: 1-800-621-7619; fax: 708-285-0797; Web site: http://www.nsc.org.
Z49.1-67 Safety in Welding and Cutting, IBR approved for § 1910.252(c)(1)(iv) (A) and (B).
Z53.1-1967 (also referred to as ANSI Z53.1-1967), Safety Color Code for Marking Physical Hazards, ANSI approved October 9, 1967; IBR approved for § 1910.97(a) and 1910.145(d). Copies available for purchase from the IHS Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 1-877-413-5184; Web site: www.global.ihs.com.
Z535.1-2006 (R2011), Safety Colors, reaffirmed July 19, 2011; IBR approved for §§ 1910.97(a) and 1910.145(d). Copies available for purchase from the:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 877-413-5184; Web site: www.global.ihs.com; or
Z535.2-2011, Environmental and Facility Safety Signs, published September 15, 2011; IBR approved for § 1910.261(c). Copies available for purchase from the:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 877-413-5184; Web site: www.global.ihs.com; or
Z54.1-63 Safety Standard for Non-Medical X-Ray and Sealed Gamma Ray Sources, IBR approved for § 1910.252(d) (1)(vii) and (2)(ii).
Z87.1-2010, Occupational and Educational Personal Eye and Face Protection Devices, Approved April 13, 2010; IBR approved for § 1910.133(b). Copies are available for purchase from:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: (877) 413-5184; Web site: http://global.ihs.com; or
Z87.1-2003, Occupational and Educational Eye and Face Personal Protection Devices Approved June 19, 2003; IBR approved for §§ 1910.133(b). Copies available for purchase from the:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: (877) 413-5184; Web site: http://global.ihs.com; or
Z87.1-1989 (R-1998), Practice for Occupational and Educational Eye and Face Protection, Reaffirmation approved January 4, 1999; IBR approved for § 1910.133(b). Copies are available for purchase from:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: (877) 413-5184; Web site: http://global.ihs.com; or
Z88.2-1969, Practices for Respiratory Protection; IBR approved for §§ 1910.94(c)(6)(iii)( a ), 1910.134(c); and 1910.261(a)(3)(xxvi), (b)(2), (f)(5), (g)(15)(v), (h)(2)(iii), (h)(2)(iv), and (i)(4).
Z41.1-1967 Men's Safety Toe Footwear; IBR approved for § 1910.261(i)(4).
Z87.1-1968 Practice of Occupational and Educational Eye and Face Protection; IBR approved for § 1910.261(a)(3)(xxv), (d)(1)(ii), (f)(5), (g)(1), (g)(15)(v), (g)(18)(ii), and (i)(4).
Z89.1-1969 Safety Requirements for Industrial Head Protection; IBR approved for § 1910.261(a)(3)(xxvii), (b)(2), (g)(15)(v), and (i)(4).
Z89.2-1971 Safety Requirements for Industrial Protective Helmets for Electrical Workers, Class B; IBR approved for § 1910.268(i)(1).
1957) Specification for Large Welded Production Tanks, 7th Ed., IBR approved for § 1910.106(b)(1)(i)( a )( 3 ).
1961) Specification for Small Welded Production Tanks, 5th Ed., IBR approved for § 1910.106(b)(1)(i)( a )( 3 ).
Fourth Ed.
VIII, 1949, 1950, 1952, 1956, 1959, and 1962 Ed., IBR approved for §§ 1910.110 (b)(10)(iii) (Table H-26), (d)(2) (Table H-31); (e)(3)(i) (Table H-32), (h)(2) (Table H-34); and 1910.111(b)(2)(vi);
Code for Pressure Vessels, 1968 Ed., IBR approved for §§ 1910.106(i)(3)(i); 1910.110(g)(2)(iii)( b )( 2 ); and 1910.217(b)(12);
VIII, 1968, IBR approved for §§ 1910.103; 1910.104(b)(4)(ii); 1910.106 (b)(1)(iv)( b )( 2 ) and ( i )(3)(ii); 1910.107; 1910.110(b)(11) (i)( b ) and (iii)( a )( 1 ); 1910.111(b)(2) (i), (ii), and (iv); and 1910.169(a)(2) (i) and (ii);
VIII, Paragraph UG-84, 1968, IBR approved for § 1910.104 (b)(4)(ii) and (b)(5)(iii);
VIII, Unfired Pressure Vessels, Including Addenda (1969), IBR approved for §§ 1910.261; 1910.262; 1910.263(i)(24)(ii);
B56.6-1992 (with addenda), Safety Standard for Rough Terrain Forklift Trucks, IBR approved for § 1910.266(f)(4).
International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959; phone: (610) 832-9585; email: [email protected]; website: www.astm.org.
Malleable Iron Castings, IBR approved for § 1910.111.
Welded and Seamless Steel Pipe, IBR approved for §§ 1910.110 and 1910.111.
Gray Iron Casting for Valves, Flanges and Pipe Fitting, IBR approved for § 1910.111.
Ductile Iron for Use at Elevated Temperatures, IBR approved for § 1910.111.
Seamless Copper Water Tube, IBR approved for § 1910.252.
Seamless Copper Water Tube, IBR approved for § 1910.110.
Aluminum-Alloy Drawn Seamless Tubes, IBR approved for § 1910.110.
Standard Specifications for Aluminum-Alloy Seamless Pipe and Seamless Extruded Tube, IBR approved for § 1910.110.
Test for Penetration by Bituminous Materials, IBR approved for § 1910.106.
Test for Flash Point by Tag Closed Tester, IBR approved for § 1910.106.
Standard Test Method for Flash Point by Tag Closed Cup Tester, Approved May 1, 2005, IBR approved for Appendix B to § 1910.1200.
Test for Distillation of Petroleum Products, IBR approved for §§ 1910.106 and 1910.119.
86-07a, Standard Test Method for Distillation of Petroleum Products at Atmospheric Pressure, Approved April 1, 2007, IBR approved for Appendix B to § 1910.1200.
Test for Saybolt Viscosity, IBR approved for § 1910.106.
Test for Flash Point by Pensky Martens, IBR approved for § 1910.106.
Standard Test Methods for Flash Point by Pensky-Martens Closed Cup Tester, Approved Oct. 15, 2008, IBR approved for Appendix B to § 1910.1200.
Standard Test Method of Test for Vapor Pressure of Petroleum Products (Reid Method), IBR approved for § 1910.106.
Test for Viscosity of Transparent and Opaque Liquids, IBR approved for § 1910.106.
Standard Test Method for Distillation Range of Volatile Organic Liquids, Approved May 15, 2005, IBR approved for Appendix B to § 1910.1200.
Test for Flammability of Plastic Sheeting and Cellular Plastics, IBR approved for § 1910.103.
Conversion Tables for SUS, IBR approved for § 1910.106.
Standard Test Methods for Flash Point of Liquids by Small Scale Closed-Cup Apparatus, Approved November 1, 2004, IBR approved for Appendix B to § 1910.1200.
3828-07a, Standard Test Methods for Flash Point by Small Scale Closed Cup Tester, Approved July 15, 2007, IBR approved for Appendix B to § 1910.1200.
Standard Test Methods for Foot Protection, IBR approved for § 1910.136.
Standard Specification for Performance Requirements for Protective Footwear, IBR approved for § 1910.136.
B3.0-41 Standard Qualification Procedure, IBR approved for § 1910.67(c)(5)(i).
D1.0-1966 Code for Welding in Building Construction, IBR approved for § 1910.27(b)(6).
D2.0-69 Specifications for Welding Highway and Railway Bridges, IBR approved for § 1910.67(c)(5)(iv).
D8.4-61 Recommended Practices for Automotive Welding Design, IBR approved for § 1910.67(c)(5)(ii).
D10.9-69 Standard Qualification of Welding Procedures and Welders for Piping and Tubing, IBR approved for § 1910.67(c)(5)(iii).
Acetylene, Twelfth Edition, IBR approved for § 1910.102(a). Copies of CGA Pamphlet G-1-2009 are available for purchase from the: Compressed Gas Association, Inc., 4221 Walney Road, 5th Floor, Chantilly, VA 20151; telephone: (703) 788-2700; fax: (703) 961-1831; email: [email protected].
G-7.1 (1966) Commodity Specification, IBR approved for § 1910.134(d)(1).
G-8.1 (1964) Standard for the Installation of Nitrous Oxide Systems at Consumer Sites, IBR approved for § 1910.105.
Safety Release Device Standards—Cylinders for Compressed Gases, IBR approved for §§ 1910.101(c); 1910.103(c)(1)(iv)( a )( 2 ).
S-1.2 (1963) Safety Release Device Standards, Cargo and Portable Tanks for Compressed Gases, IBR approved for §§ 1910.101(c); 1910.103(c)(1)(iv)( a )( 2 ).
S-1.3 (1959) Safety Release Device Standards-Compressed Gas Storage Containers, IBR approved for §§ 1910.103(c)(1)(iv)( a )( 2 ); 1910.104(b)(6)(iii); and 1910.111(d)(4)(ii)( b ).
Standard Hose Connection Standard, IBR approved for § 1910.253(e) (4)(v) and (5)(iii).
and RMA (Rubber Manufacturer's Association) Specification for Rubber Welding Hose (1958), IBR approved for § 1910.253(e)(5)(i).
Regulator Connection Standard, IBR approved for § 1910.253(e) (4)(iv) and (6).
Specification 1B61, Specifications for Electric Overhead Traveling Cranes, IBR approved for § 1910.179(b)(6)(i).
51794:2003-05—Determining the ignition temperature of petroleum products, May 2003, IBR approved for appendix B to § 1910.1200.
GG-B-0067b, Air Compressed for Breathing Purposes, or Interim Federal Specifications, Apr. 1965, IBR approved for § 1910.134(d)(4).
Explosive atmospheres—Part 20-1: Material characteristics for gas and vapor classification—Test methods and data, Edition 1.0, 2010-01; IBR approved for appendix B to § 1910.1200.
International Fire Code, copyright 2009, IBR approved for §§ 1910.34, 1910.35, 1910.36, and 1910.37.
76-120 (1975), List of Personal Hearing Protectors and Attenuation Data, IBR approved for § 1910.95 App. B.
17, 1960, Safety in the Handling and Use of Explosives, IBR approved for §§ 1910.261 (a)(4)(iii) and (c)(14)(ii).
817:2014(E), Refrigerants—Designation and safety classification, Third edition, 2014-04-15; IBR approved for appendix B to § 1910.1200.
10156:1996 (E), Gases and Gas Mixtures—Determination of Fire Potential and Oxidizing Ability for the Selection of Cylinder Valve Outlets, Second Edition, Feb. 15, 1996; IBR approved for appendix B to § 1910.1200.
10156:2017(E), Gas Cylinders—Gases and gas mixtures—Determination of fire potential and oxidizing ability for the selection of cylinder valve outlets, Fourth edition, 2017-07; IBR approved for appendix B to § 1910.1200.
10156-2:2005 (E), Gas cylinders—Gases and Gas Mixtures—Part 2: Determination of Oxidizing Ability of Toxic and Corrosive Gases and Gas Mixtures, First Edition, Aug. 1, 2005; IBR approved for appendix B to subpart Z.
13943:2000 (E/F); Fire Safety—Vocabulary, First Edition, April, 15, 2000, IBR approved for appendix B to § 1910.1200.
Standard for Dry Cleaning Plants, IBR approved for § 1910.106(j)(6)(i).
Standard for Spray Finishing Using Flammable and Combustible Material, IBR approved for § 1910.94(c)(2).
Standard for Dip Tanks Containing Flammable or Combustible Liquids, IBR approved for § 1910.124(b)(4)(iv).
Standard for Dip Tanks Containing Flammable or Combustible Liquids, IBR approved for § 1910.124(b)(4)(ii).
Standard for the Manufacture of Organic Coatings, IBR approved for § 1910.106(j)(6)(ii).
Standard for Solvent Extraction Plants, IBR approved for § 1910.106(j)(6)(iii).
Standard for the Installation and Use of Stationary Combustion Engines and Gas Turbines, IBR approved for §§ 1910.106(j)(6)(iv) and 1910.110 (b)(20)(iv)(c) and (e)(11).
Standard for Fire Protection in Use of Cutting and Welding Processes, IBR approved for § 1910.252(a)(1) introductory text.
Standard for the Installation of Gas Appliances and Gas Piping, IBR approved for § 1910.110(b)(20)(iv)(a).
Standard for the Installation of Gas Piping and Gas Equipment on Industrial Premises and Certain Other Premises, IBR approved for § 1910.110(b)(20)(iv)(b).
Standard for the Storage and Handling of Liquefied Petroleum Gases (ANSI Z106.1-1970), IBR approved for §§ 1910.110 (b)(3)(iv) and (i)(3) (i) and (ii); and 1910.178(f)(2).
Standard for the Storage and Handling of Liquefied Petroleum Gases at Utility Gas Plants, IBR approved for §§ 1910.110 (b)(3)(iv) and (i)(2)(iv).
Standard for the Prevention of Dust Explosions in the Production, Packaging, and Handling of Pulverized Sugar and Cocoa, IBR approved for § 1910.263(k)(2)(i).
Guide for Explosion Venting, IBR approved for § 1910.94(a)(2)(iii).
Lightning Protection Code, IBR approved for § 1910.109(i)(6)(ii).
Standard for Fire Doors and Windows, IBR approved for § 1910.106(d)(4)(i).
Standard for the Installation of Fire Doors and Windows, IBR approved for § 1910.253(f)(6)(i)(I).
Standard for Oven and Furnaces Design, Location and Equipment, IBR approved for §§ 1910.107 (j)(1) and (l)(3) and 1910.108 (b)(2) and (d)(2).
Standard for the Installation of Blower and Exhaust Systems for Dust, Stock, and Vapor Removal or Conveying (ANSI Z33.1-61), IBR approved for § 1910.107(d)(1).
Standards for Blower and Exhaust Systems, IBR approved for § 1910.108(b)(1).
Standard for the Installation of Equipment for the Removal of Smoke and Grease Laden Vapors from Commercial Cooking Equipment, IBR approved for § 1910.110(b)(20)(iv)(d).
Code for Life Safety From Fire in Buildings and Structures, IBR approved for § 1910.261(a)(4)(ii).
Life Safety Code, 2009 edition, IBR approved for §§ 1910.34, 1910.35, 1910.36, and 1910.37.
Manual on Roof Coverings, IBR approved for § 1910.109(i)(1)(iii)(c).
Standard Methods of Fire Tests of Building Construction and Materials, IBR approved for §§ 1910.106 (d)(3)(ii) introductory text and (d)(4)(i).
Fire Protection Standard for Motor-Craft (Pleasure and Commercial), IBR approved for § 1910.265(d)(2)(iv) introductory text.
Recommended Regulatory Standard for Tank Vehicles for Flammable and Combustible Liquids, IBR approved for § 1910.106(g)(1)(i)(e)(1).
Standard for Purged Enclosures for Electrical Equipment in Hazardous Locations, IBR approved for § 1910.103(c)(1)(ix)(e)(1).
Standard for Type Designations, Areas of Use, Maintenance, and Operation of Powered Industrial Trucks, IBR approved for § 1910.110(e)(2)(iv).
Standard for the Installation of Bulk Oxygen Systems at Consumer Sites, IBR approved for §§ 1910.253 (b)(4)(iv) and (c)(2)(v).
Code for the Prevention of Dust Ignition in Spice Grinding Plants, IBR approved for § 1910.263(k)(2)(i).
Protective Clothing for Structural Fire Fighting, IBR approved for § 1910.156(e)(3)(ii) introductory text.
Code for the Manufacture and Storage of Aerosol Products, 2007 Edition, Approved August 17, 2006, IBR approved for Appendix B to § 1910.1200.
1964), IBR approved for § 1910.109 Table H-22, ftn. 3.
1987), IBR approved for § 1910.120 PEL definition.
Pharmacopeia, IBR approved for § 1910.134(d)(1).
934 (1962), Food Service Sanitation Ordinance and Code, part V of the Food Service Sanitation Manual, IBR approved for § 1910.142(i)(1).
June 1988, Recommended Practice for Access Systems for Off-Road Machines, IBR approved for § 1910.266(f)(5)(i).
January 1981, Minimum Performance Criteria for Falling Object Protective Structure (FOPS), IBR approved for § 1910.266(f)(3)(ii).
June 1985, Operator Restraint Systems for Off-Road Work Machines, IBR approved for § 1910.266(d)(3)(iv).
April 1988, Deflection Limiting Volume-ROPS/FOPS Laboratory Evaluation, IBR approved for § 1910.266(f)(3)(iv).
Crane Loading Stability Test Code, IBR approved for § 1910.180 (c)(1)(iii) and (e)(2)(iii)( a ).
April 1988, Performance Criteria for Rollover Protective Structures (ROPS) for Construction, Earthmoving, Forestry and Mining Machines, IBR approved for § 1910.266(f)(3)(ii).
Steel Underground Tanks for Flammable and Combustible Liquids, 5th Ed., IBR approved for § 1910.106(b)(1)(iii)( a )( 1 ).
Steel Inside Tanks for Oil-Burner Fuel, IBR approved for § 1910.106(b)(1)(iii)( a )( 1 ).
Steel Above Ground Tanks for Flammable and Combustible Liquids, IBR approved for § 1910.106(b)(1)(iii)( a )( 1 ).
Box 960 Herndon, VA 20172; phone: (703) 661-1571;; email: [email protected] ; website: https://shop.un.org/.
European Agreement Concerning the International Carriage of Dangerous Goods by Road; Annex A: General provisions and provisions concerning dangerous substances and articles; (Volumes I and II) including December 2018 corrigendum to Volume II, applicable January 1, 2019; IBR approved for § 1910.1200.
[39 FR 23502, June 27, 1974]
Editorial Note:
Federal Register
www.govinfo.gov.
This section shall apply only when the term nationally recognized testing laboratory is used in other sections of this part.
The term nationally recognized testing laboratory (NRTL) means an organization which is recognized by OSHA in accordance with appendix A of this section and which tests for safety, and lists or labels or accepts, equipment or materials and which meets all of the following criteria:
An appropriate test standard referred to in § 1910.7(b)(1) (i) and (ii) is a document which specifies the safety requirements for specific equipment or class of equipment and is:
If a testing laboratory desires to use a test standard other than one allowed under paragraph (c) of this section, then the Assistant Secretary of Labor shall evaluate the proposed standard to determine that it provides an adequate level of safety before it is used.
A testing organization desiring recognition by OSHA as an NRTL shall request that OSHA evaluate its testing and control programs against the requirements in this section for any equipment or material it may specify. The recognition procedure shall be conducted in accordance with appendix A to this section.
Activity Fee = [Average (or Actual) Hours to Complete the Activity × Staff Costs per Hour] + Average (or Actual) Travel Costs
will review the full costs periodically and will propose a revised fee schedule, if warranted. In its review, OSHA will apply the formula established in paragraph (f)(2) of this section to the current estimated full costs for the NRTL Program. If a change is warranted, OSHA will follow the implementation shown in paragraph (f)(4) of this section.
will publish all fee schedules in the Federal Register. Once published, a fee schedule remains in effect until it is superseded by a new fee schedule. Any member of the public may request a change to the fees included in the current fee schedule. Such a request must include appropriate documentation in support of the suggested change. OSHA will consider such requests during its annual review of the fee schedule.
will implement periodic review, and fee assessment, collection, and payment, as follows:
| Milestones/Dates | Action required |
|---|---|
| I. Periodic Review of Fee Schedule | |
| When review completed | OSHA will publish any proposed new fee schedule in the Federal Register if OSHA determines that costs warrant changes in the fee schedule. |
| Fifteen days after publication | Comments due on the proposed new fee schedule. |
| When OSHA approves the fee schedule | OSHA will publish the final fee schedule in the Federal Register, making the fee schedule effective on a specific date. |
| II. Application Processing Fees | |
| Time of application | Applicant must pay the applicable fees in the fee schedule that are due when submitting an application; OSHA will not begin processing the application until it receives the fees. |
| Before assessment performed | Applicant must pay the estimated staff time and travel costs for its assessment based on the fees in effect at the time of the assessment. Applicant also must pay the fees for the final report and Federal Register notice, and other applicable fees, as specified in the fee schedule. OSHA may cancel an application if the applicant does not pay these fees, or any balance of these fees, when due. |
| III. Audit Fees | |
| Before audit performed | NRTL must pay the estimated staff time and travel costs for its audit based on the fees in effect at the time of the audit. NRTL also must pay other applicable fees, as specified in the fee schedule. After the audit, OSHA adjusts the audit fees to account for the actual costs for travel and staff time. |
| On due date | NRTL must pay the estimated audit fees, or any balance due, by the due date established by OSHA; OSHA will assess a late fee if NRTL does not pay audit fees (or any balance of fees due) by the due date. OSHA may still perform the audit when an NRTL does not pay the fees or does not pay them on time. |
| Thirty days after due date or, if earlier, date NRTL refuses to pay | OSHA will begin processing a notice for publication in the Federal Register announcing its plan to revoke recognition for NRTLs that do not pay the estimated audit fees and any balance of audit fees due. |
| Note: For the purposes of 29 CFR 1910.7(f)(4), “days” means “calendar days,” and “applicant” means “the NRTL” or “an applicant for NRTL recognition.” |
will provide details about how to pay the fees through appropriate OSHA Program Directives, which will be available on the OSHA web site.
Appendix A to § 1910.7—OSHA Recognition Process for Nationally Recognized Testing Laboratories
Introduction
This appendix provides requirements and criteria which OSHA will use to evaluate and recognize a Nationally Recognized Testing Laboratory (NRTL). This process will include the evaluation of the product evaluation and control programs being operated by the NRTL, as well as the NRTL's testing facilities being used in its program. In the evaluation of the NRTLs, OSHA will use either consensus-based standards currently in use nationally, or other standards or criteria which may be considered appropriate. This appendix implements the definition of NRTL in 29 CFR 1910.7 which sets out the criteria that a laboratory must meet to be recognized by OSHA (initially and on a continuing basis). The appendix is broader in scope, providing procedures for renewal, expansion and revocation of OSHA recognition. Except as otherwise provided, the burden is on the applicant to establish by a preponderance of the evidence that it is entitled to recognition as an NRTL. If further detailing of these requirements and criteria will assist the NRTLs or OSHA in this activity, this detailing will be done through appropriate OSHA Program Directives.
I. Procedures for Initial OSHA Recognition
A. Applications.
1. Eligibility. a. Any testing agency or organization considering itself to meet the definition of nationally recognized testing laboratory as specified in § 1910.7 may apply for OSHA recognition as an NRTL.
b. However, in determining eligibility for a foreign-based testing agency or organization, OSHA shall take into consideration the policy of the foreign government regarding both the acceptance in that country of testing data, equipment acceptances, and listings, and labeling, which are provided through nationally recognized testing laboratories recognized by the Assistant Secretary, and the accessibility to government recognition or a similar system in that country by U.S.-based safety-related testing agencies, whether recognized by the Assistant Secretary or not, if such recognition or a similar system is required by that country.
2. Content of application. a. The applicant shall provide sufficient information and detail demonstrating that it meets the requirements set forth in § 1910.7, in order for an informed decision concerning recognition to be made by the Assistant Secretary.
b. The applicant also shall identify the scope of the NRTL-related activity for which the applicant wishes to be recognized. This will include identifying the testing methods it will use to test or judge the specific equipment and materials for which recognition is being requested, unless such test methods are already specified in the test standard. If requested to do so by OSHA, the applicant shall provide documentation of the efficacy of these testing methods.
c. The applicant may include whatever enclosures, attachments, or exhibits the applicant deems appropriate. The application need not be submitted on a Federal form.
3. Filing office location. The application shall be filed with: NRTL Recognition Program, Occupational Safety and Health Administration, U.S. Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210.
4. Amendments and withdrawals. a. An application may be revised by an applicant at any time prior to the completion of activity under paragraph I.B.4. of this appendix.
b. An application may be withdrawn by an applicant, without prejudice, at any time prior to the final decision by the Assistant Secretary in paragraph I.B.7.c. of this appendix.
B. Review and Decision Process; Issuance or Renewal.
1. Acceptance and on-site review. a. Applications submitted by eligible testing agencies will be accepted by OSHA, and their receipt acknowledged in writing. After receipt of an application, OSHA may request additional information if it believes information relevant to the requirements for recognition has been omitted.
b. OSHA shall, as necessary, conduct an on-site review of the testing facilities of the applicant, as well as the applicant's administrative and technical practices, and, if necessary, review any additional documentation underlying the application.
c. These on-site reviews will be conducted by qualified individuals technically expert in these matters, including, as appropriate, non-Federal consultants/contractors acceptable to OSHA. The protocol for each review will be based on appropriate national consensus standards or international guides, with such additions, changes, or deletions as may be considered necessary and appropriate in each case by OSHA. A written report shall be made of each on-site review and a copy shall be provided to the applicant.
2. Positive finding by staff. If, after review of the application, and additional information, and the on-site review report, the applicant appears to have met the requirements for recognition, a written recommendation shall be submitted by the responsible OSHA personnel to the Assistant Secretary that the application be approved, accompanied by a supporting explanation.
3. Negative finding by staff. —a. Notification to applicant. If, after review of the application, any additional information and the on-site review report, the applicant does not appear to have met the requirements for recognition, the responsible OSHA personnel shall notify the applicant in writing, listing the specific requirements of § 1910.7 and this appendix which the applicant has not met, and allow a reasonable period for response.
b. Revision of application.
4. Preliminary finding by Assistant Secretary. a. The Assistant Secretary, or a special designee for this purpose, will make a preliminary finding as to whether the applicant has or has not met the requirements for recognition, based on the completed application file, the written staff recommendation, and the statement of reasons supplied by the applicant if there remains a staff recommendation of disapproval.
b. Notification of this preliminary finding will be sent to the applicant and subsequently published in the Federal Register.
c. This preliminary finding shall not be considered an official decision by the Assistant Secretary or OSHA, and does not confer any change in status or any interim or temporary recognition for the applicant.
5. Public review and comment period —a. The Federal Register notice of preliminary finding will provide a period of not less than 30 calendar days for written comments on the applicant's fulfillment of the requirements for recognition. The application, supporting documents, staff recommendation, statement of applicant's reasons, and any comments received, will be available for public inspection in the OSHA Docket Office.
b. Any member of the public, including the applicant, may supply detailed reasons and evidence supporting or challenging the sufficiency of the applicant's having met the requirements of the definition in 29 CFR § 1910.7 and this appendix. Submission of pertinent documents and exhibits shall be made in writing by the close of the comment period.
6. Action after public comment —a. Final decision by Assistant Secretary. Where the public review and comment record supports the Assistant Secretary's preliminary finding concerning the application, i.e., absent any serious objections or substantive claims contrary to the preliminary finding having been received in writing from the public during the comment period, the Assistant Secretary will proceed to final written decision on the application. The reasons supporting this decision shall be derived from the evidence available as a result of the full application, the supporting documentation, the staff finding, and the written comments and evidence presented during the public review and comment period.
b. Public announcement. A copy of the Assistant Secretary's final decision will be provided to the applicant. Subsequently, a notification of the final decision shall be published in the Federal Register. The publication date will be the effective date of the recognition.
c. Review of final decision. There will be no further review activity available within the Department of Labor from the final decision of the Assistant Secretary.
7. Action after public objection —a. Review of negative information. At the discretion of the Assistant Secretary or his designee, OSHA may authorize Federal or contract personnel to initiate a special review of any information provided in the public comment record which appears to require resolution, before a final decision can be made.
b. Supplementation of record. The contents and results of special reviews will be made part of this record by the Assistant Secretary by either:
c. Final decision by the Assistant Secretary. The Assistant Secretary shall issue a decision as to whether it has been demonstrated, based on a preponderance of the evidence, that the applicant meets the requirements for recognition. The reasons supporting this decision shall be derived from the evidence available as a result of the full application, the supporting documentation, the staff finding, the comments and evidence presented during the public review and comment period, and written to transcribed evidence received during any subsequent reopening of the written comment period or informal public hearing held.
d. Public announcement. A copy of the Assistant Secretary's final decision will be provided to the applicant, and a notification will be published in the Federal Register subsequently announcing the decision.
e. Review of final decision. There will be no further review activity available within the Department of Labor from the final decision of the Assistant Secretary.
C. Terms and Conditions of Recognition.
1. The following terms and conditions shall be part of every recognition:
a. Letter of recognition. The recognition by OSHA of any NRTL will be evidenced by a letter of recognition from OSHA. The letter will provide the specific details of the scope of the OSHA recognition, including the specific equipment or materials for which OSHA recognition has been granted, as well as any specific conditions imposed by OSHA.
b. Period of recognition. The recognition by OSHA of each NRTL will be valid for five years, unless terminated before the expiration of the period. The dates of the period of recognition will be stated in the recognition letter.
c. Constancy in operations. The recognized NRTL shall continue to satisfy all the requirements or limitations in the letter of recognition during the period of recognition.
d. Accurate publicity. The OSHA-recognized NRTL shall not engage in or permit others to engage in misrepresentation of the scope or conditions of its recognition.
2. [Reserved]
II. Supplementary Procedures.
A. Test standard changes.
A recognized NRTL may change a testing standard or elements incorporated in the standard such as testing methods or pass-fail criteria by notifying the Assistant Secretary of the change, certifying that the revised standard will be at least as effective as the prior standard, and providing the supporting data upon which its conclusions are based. The NRTL need not inform the Assistant Secretary of minor deviations from a test standard such as the use of new instrumentation that is more accurate or sensitive than originally called for in the standard. The NRTL also need not inform the Assistant Secretary of its adoption of revisions to third-party testing standards meeting the requirements of § 1910.7(c)(4), if such revisions have been developed by the standards developing organization, or of its adoption of revisions to other third-party test standards which the developing organization has submitted to OSHA. If, upon review, the Assistant Secretary or his designee determines that the proposed revised standard is not “substantially equivalent” to the previous version with regard to the level of safety obtained, OSHA will not accept the proposed testing standard by the recognized NRTL, and will initiate discontinuance of that aspect of OSHA-recognized activity by the NRTL by modification of the official letter of recognition. OSHA will publicly announce this action and the NRTL will be required to communicate this OSHA decision directly to affected manufacturers.
B. Expansion of current recognition
1. Eligibility. A recognized NRTL may apply to OSHA for an expansion of its current recognition to cover other categories of NRTL testing in addition to those included in the current recognition.
2. Procedure. a. OSHA will act upon and process the application for expansion in accordance with subsection I.B. of this appendix, except that the period for written comments, specified in paragraph 5.a of subsection I.B. of this appendix, will be not less than 15 calendar days.
b. In that process, OSHA may decide not to conduct an on-site review, where the substantive scope of the request to expand recognition is closely related to the current area of recognition.
c. The expiration date for each expansion of recognition shall coincide with the expiration date of the current basic recognition period.
C. Renewal of OSHA recognition
1. Eligibility. A recognized NRTL may renew its recognition by filing a renewal request at the address in paragraph I.A.3. of this appendix not less than nine months, nor more than one year, before the expiration date of its current recognition.
2. Procedure. a. OSHA will process the renewal request in accordance with subsection I.B. of this appendix, except that the period for written comments, specified in paragraph 5.a of subsection I.B. of this appendix, will be not less than 15 calendar days.
b. In that process, OSHA may determine not to conduct the on-site reviews in I.B.1.a. where appropriate.
c. When a recognized NRTL has filed a timely and sufficient renewal request, its current recognition will not expire until a final decision has been made by OSHA on the request.
d. After the first renewal has been granted to the NRTL, the NRTL shall apply for a continuation of its recognition status every five years by submitting a renewal request. In lieu of submitting a renewal request after the initial renewal, the NRTL may certify its continuing compliance with the terms of its letter of recognition and 29 CFR 1910.7.
3. Alternative procedure. After the initial recognition and before the expiration thereof, OSHA may (for good cause) determine that there is a sufficient basis to dispense with the renewal requirement for a given laboratory and will so notify the laboratory of such a determination in writing. In lieu of submitting a renewal request, any laboratory so notified shall certify its continuing compliance with the terms of its letter of recognition and 29 CFR 1910.7.
D. Voluntary termination of recognition.
At any time, a recognized NRTL may voluntarily terminate its recognition, either in its entirety or with respect to any area covered in its recognition, by giving written notice to OSHA. The written notice shall state the date as of which the termination is to take effect. The Assistant Secretary shall inform the public of any voluntary termination by Federal Register notice.
E. Revocation of recognition by OSHA.
1. Potential causes. If an NRTL either has failed to continue to substantially satisfy the requirements of § 1910.7 or this appendix, or has not been reasonably performing the NRTL testing requirements encompassed within its letter of recognition, or has materially misrepresented itself in its applications or misrepresented the scope or conditions of its recognition, the Assistant Secretary may revoke the recognition of a recognized NRTL, in whole or in part. OSHA may initiate revocation procedures on the basis of information provided by any interested person.
2. Procedure. a. Before proposing to revoke recognition, the Agency will notify the recognized NRTL in writing, giving it the opportunity to rebut or correct the alleged deficiencies which would form the basis of the proposed revocation, within a reasonable period.
b. If the alleged deficiencies are not corrected or reconciled within a reasonable period, OSHA will propose, in writing to the recognized NRTL, to revoke recognition. If deemed appropriate, no other announcement need be made by OSHA.
c. The revocation shall be effective in 60 days unless within that period the recognized NRTL corrects the deficiencies or requests a hearing in writing.
d. If a hearing is requested, it shall be held before an administrative law judge of the Department of Labor pursuant to the rules specified in 29 CFR part 1905, subpart C.
e. The parties shall be OSHA and the recognized NRTL. The Assistant Secretary may allow other interested persons to participate in these hearings if such participation would contribute to the resolution of issues germane to the proceeding and not cause undue delay.
f. The burden of proof shall be on OSHA to demonstrate by a preponderance of the evidence that the recognition should be revoked because the NRTL is not meeting the requirements for recognition, has not been reasonably performing the product testing functions as required by § 1910.7, this appendix A, or the letter of recognition, or has materially misrepresented itself in its applications or publicity.
3. Final decision. a. After the hearing, the Administrative Law Judge shall issue a decision stating the reasons based on the record as to whether it has been demonstrated, based on a preponderance of evidence, that the applicant does not continue to meet the requirements for its current recognition.
b. Upon issuance of the decision, any party to the hearing may file exceptions within 20 days pursuant to 29 CFR 1905.28. If no exceptions are filed, this decision is the final decision of the Assistant Secretary. If objections are filed, the Administrative Law Judge shall forward the decision, exceptions and record to the Assistant Secretary for the final decision on the proposed revocation.
c. The Assistant Secretary will review the record, the decision by the Administrative Law Judge, and the exceptions filed. Based on this, the Assistant Secretary shall issue the final decision as to whether it has been demonstrated, by a preponderance of evidence, that the recognized NRTL has not continued to meet the requirements for OSHA recognition. If the Assistant Secretary finds that the NRTL does not meet the NRTL recognition requirements, the recognition will be revoked.
4. Public announcement. A copy of the Assistant Secretary's final decision will be provided to the applicant, and a notification will be published in the Federal Register announcing the decision, and the availability of the complete record of this proceeding at OSHA. The effective date of any revocation will be the date the final decision copy is sent to the NRTL.
5. Review of final decision. There will be no further review activity available within the Department of Labor from the final decision of the Assistant Secretary.
[53 FR 12120, Apr. 12, 1988; 53 FR 16838, May 11, 1988, as amended at 54 FR 24333, June 7, 1989; 65 FR 46818, 46819, July 31, 2000; 76 FR 10515, Feb. 25, 2011; 85 FR 8732, Feb. 18, 2020]
The following sections or paragraphs each contain a collection of information requirement which has been approved by the Office of Management and Budget under the control number listed.
| 29 CFR citation | OMB control No. |
|---|---|
| 1910.7 | 1218-0147 |
| 1910.23 | 1218-0199 |
| 1910.27 | 1218-0199 |
| 1910.28 | 1218-0199 |
| 1910.66 | 1218-0121 |
| 1910.67(b) | 1218-0230 |
| 1910.68 | 1218-0226 |
| 1910.95 | 1218-0048 |
| 1910.111 | 1218-0208 |
| 1910.119 | 1218-0200 |
| 1910.120 | 1218-0202 |
| 1910.132 | 1218-0205 |
| 1910.134 | 1218-0099 |
| 1910.137 | 1218-0190 |
| 1910.142 | 1218-0096 |
| 1910.145 | 1218-0132 |
| 1910.146 | 1218-0203 |
| 1910.147 | 1218-0150 |
| 1910.156 | 1218-0075 |
| 1910.157(e)(3) | 1218-0210 |
| 1910.157(f)(16) | 1218-0218 |
| 1910.177(d)(3)(iv) | 1218-0219 |
| 1910.179(j)(2)(iii) and (iv) | 1218-0224 |
| 1910.179(m)(1) and (m)(2) | 1218-0224 |
| 1910.180(d)(6) | 1218-0221 |
| 1910.180(g)(1) and (g)(2)(ii) | 1218-0221 |
| 1910.181(g)(1) and (g)(3) | 1218-0222 |
| 1910.184(e)(4), (f)(4) and (i)(8)(ii) | 1218-0223 |
| 1910.217(e)(1)(i) and (ii) | 1218-0229 |
| 1910.217(g) | 1218-0070 |
| 1910.217(h) | 1218-0143 |
| 1910.218(a)(2)(i) and (ii) | 1218-0228 |
| 1910.252(a)(2)(xiii)( c ) | 1218-0207 |
| 1910.255(e) | 1218-0207 |
| 1910.266 | 1218-0198 |
| 1910.268 | 1218-0225 |
| 1910.269 | 1218-0190 |
| 1910.272 | 1218-0206 |
| 1910.302 | 1218-0256 |
| 1910.303 | 1218-0256 |
| 1910.304 | 1218-0256 |
| 1910.305 | 1218-0256 |
| 1910.306 | 1218-0256 |
| 1910.307 | 1218-0256 |
| 1910.308 | 1218-0256 |
| 1910.420 | 1218-0069 |
| 1910.421 | 1218-0069 |
| 1910.423 | 1218-0069 |
| 1910.430 | 1218-0069 |
| 1910.440 | 1218-0069 |
| 1910.1001 | 1218-0133 |
| 1910.1003 | 1218-0085 |
| 1910.1004 | 1218-0084 |
| 1910.1006 | 1218-0086 |
| 1910.1007 | 1218-0083 |
| 1910.1008 | 1218-0087 |
| 1910.1009 | 1218-0089 |
| 1910.1010 | 1218-0082 |
| 1910.1011 | 1218-0090 |
| 1910.1012 | 1218-0080 |
| 1910.1013 | 1218-0079 |
| 1910.1014 | 1218-0088 |
| 1910.1015 | 1218-0044 |
| 1910.1016 | 1218-0081 |
| 1910.1017 | 1218-0010 |
| 1910.1018 | 1218-0104 |
| 1910.1020 | 1218-0065 |
| 1910.1024 | 1218-0267 |
| 1910.1025 | 1218-0092 |
| 1910.1026 | 1218-0252 |
| 1910.1027 | 1218-0185 |
| 1910.1028 | 1218-0129 |
| 1910.1029 | 1218-0128 |
| 1910.1030 | 1218-0180 |
| 1910.1043 | 1218-0061 |
| 1910.1044 | 1218-0101 |
| 1910.1045 | 1218-0126 |
| 1910.1047 | 1218-0108 |
| 1910.1048 | 1218-0145 |
| 1910.1050 | 1218-0184 |
| 1910.1051 | 1218-0170 |
| 1910.1052 | 1218-0179 |
| 1910.1053 | 1218-0266 |
| 1910.1096 | 1218-0103 |
| 1910.1200 | 1218-0072 |
| 1910.1450 | 1218-0131 |
[61 FR 5508, Feb. 13, 1996, as amended at 62 FR 29668, June 2, 1997; 62 FR 42666, Aug. 8, 1997; 62 FR 43581, Aug. 14, 1997; 62 FR 65203, Dec. 11, 1997; 63 FR 13340, Mar. 19, 1998; 63 FR 17093, Apr. 8, 1998; 71 FR 38086, July 5, 2006; 72 FR 40075, July 23, 2007; 81 FR 48710, July 26, 2016; 82 FR 31253, July 6, 2017; 83 FR 9702, Mar. 7, 2018]
Standards in this part requiring the employer to provide personal protective equipment (PPE), including respirators and other types of PPE, because of hazards to employees impose a separate compliance duty with respect to each employee covered by the requirement. The employer must provide PPE to each employee required to use the PPE, and each failure to provide PPE to an employee may be considered a separate violation.
Standards in this part requiring training on hazards and related matters, such as standards requiring that employees receive training or that the employer train employees, provide training to employees, or institute or implement a training program, impose a separate compliance duty with respect to each employee covered by the requirement. The employer must train each affected employee in the manner required by the standard, and each failure to train an employee may be considered a separate violation.
[73 FR 75583, Dec. 12, 2008]
The standards prescribed in part 1926 of this chapter are adopted as occupational safety and health standards under section 6 of the Act and shall apply, according to the provisions thereof, to every employment and place of employment of every employee engaged in construction work. Each employer shall protect the employment and places of employment of each of his employees engaged in construction work by complying with the appropriate standards prescribed in this paragraph.
For purposes of this section, Construction work means work for construction, alteration, and/or repair, including painting and decorating. See discussion of these terms in § 1926.13 of this title.
This section adopts as occupational safety and health standards under section 6 of the Act the standards which are prescribed in part 1926 of this chapter. Thus, the standards (substantive rules) published in subpart C and the following subparts of part 1926 of this chapter are applied. This section does not incorporate subparts A and B of part 1926 of this chapter. Subparts A and B have pertinence only to the application of section 107 of the Contract Work Hours and Safety Standards Act (the Construction Safety Act). For example, the interpretation of the term “subcontractor” in paragraph (c) of § 1926.13 of this chapter is significant in discerning the coverage of the Construction Safety Act and duties thereunder. However, the term “subcontractor” has no significance in the application of the Act, which was enacted under the Commerce Clause and which establishes duties for “employers” which are not dependent for their application upon any contractual relationship with the Federal Government or upon any form of Federal financial assistance.
For purposes of this section:
[58 FR 35308, June 30, 1993]
Subpart Z, § 1910.1020;
Subpart T;
Subpart S when shore-based electrical installations provide power for use aboard vessels;
Subpart Z, § 1910.1200;
Subpart Z, § 1910.1096;
Subpart G, § 1910.95;
Subpart G, § 1910.97;
Subpart I, § 1910.134;
Subpart Z applies to marine cargo handling activities except for the following:
1 The International Maritime Organization publishes the International Maritime Dangerous Goods Code to aid compliance with the international legal requirements of the International Convention for the Safety of Life at Sea, 1960.
Part 1917 of this chapter shall apply exclusively, according to the provisions thereof, to employment within a marine terminal, except as follows:
Subpart G, § 1910.94(a);
Subpart Z, § 1910.1020;
Subpart T;
Subpart S;
Subpart R, § 1910.272;
Subpart Z, § 1910.1200;
Subpart Z, § 1910.1096;
Subpart G, § 1910.95;
Subpart G, § 1910.97.
Subpart I, § 1910.134.
Subpart D, § 1910.28;
Subpart N, § 1910.177;
Subpart Z applies to marine cargo handling activities except for the following:
2 The International Maritime Organization publishes the International Maritime Dangerous Goods Code to aid compliance with the international legal requirements of the International Convention for the Safety of Life at Sea, 1960.
For purposes of this section:
[39 FR 23502, June 27, 1974, as amended at 48 FR 30908, July 5, 1983; 52 FR 36026, Sept. 25, 1987; 62 FR 40195, July 25, 1997; 63 FR 66270, Dec. 1, 1998]
[39 FR 23502, June 27, 1974, as amended at 61 FR 9235, Mar. 7, 1996]
Whenever an occupational safety and health standard adopted and incorporated by reference in this subpart B is changed pursuant to section 6(b) of the Act and the statute under which the standard was originally promulgated, and in accordance with part 1911 of this chapter, the standard shall be deemed changed for purposes of that statute and this subpart B, and shall apply under this subpart B. For the purposes of this section, a change in a standard includes any amendment, addition, or repeal, in whole or in part, of any standard.
Section 1910.1017 shall apply to the exposure of every employee to vinyl chloride in every employment and place of employment covered by § 1910.12, § 1910.13, § 1910.14, § 1910.15, or § 1910.16, in lieu of any different standard on exposure to vinyl chloride which would otherwise be applicable by virtue of any of those sections.
Section 1910.1045 shall apply to the exposure of every employee to acrylonitrile in every employment and place of employment covered by § 1910.12, § 1910.13, § 1910.14, § 1910.15, or § 1910.16, in lieu of any different standard on exposure to acrylonitrile which would otherwise be applicable by virtue of any of those sections.
Section 1910.1018 shall apply to the exposure of every employee to inorganic arsenic in every employment covered by § 1910.12, § 1910.13, § 1910.14, § 1910.15, or § 1910.16, in lieu of any different standard on exposure to inorganic arsenic which would otherwise be applicable by virtue of any of those sections.
Section 1910.1025 shall apply to the exposure of every employee to lead in every employment and place of employment covered by §§ 1910.13, 1910.14, 1910.15, and 1910.16, in lieu of any different standard on exposure to lead which would otherwise be applicable by virtue of those sections.
Section 1910.1047 shall apply to the exposure of every employee to ethylene oxide in every employment and place of employment covered by § 1910.12, § 1910.13, § 1910.14, § 1910.15, or § 1910.16, in lieu of any different standard on exposure to ethylene oxide which would otherwise be applicable by virtue of those sections.
Section 1910.1050 shall apply to the exposure of every employee to MDA in every employment and place of employment covered by § 1910.13, § 1910.14, § 1910.15, or § 1910.16, in lieu of any different standard on exposure to MDA which would otherwise be applicable by virtue of those sections.
Section 1910.1048 shall apply to the exposure of every employee to formaldehyde in every employment and place of employment covered by § 1910.12, § 1910.13, § 1910.14, § 1910.15 or § 1910.16 in lieu of any different standard on exposure to formaldehyde which would otherwise be applicable by virtue of those sections.
Section 1910.1027 shall apply to the exposure of every employee to cadmium in every employment and place of employment covered by § 1910.16 in lieu of any different standard on exposures to cadmium that would otherwise be applicable by virtue of those sections.
Section 1910.1051 shall apply to the exposure of every employee to BD in every employment and place of employment covered by § 1910.12, § 1910.13, § 1910.14, § 1910.15, or § 1910.16, in lieu of any different standard on exposure to BD which would otherwise be applicable by virtue of those sections.
Section 1910.1052 shall apply to the exposure of every employee to MC in every employment and place of employment covered by § 1910.16 in lieu of any different standard on exposure to MC which would otherwise be applicable by virtue of that section when it is not present in sealed, intact containers.
[43 FR 28473, June 30, 1978, as amended at 43 FR 45809, Oct. 3, 1978; 43 FR 53007, Nov. 14, 1978; 44 FR 5447, Jan. 26, 1979; 46 FR 32022, June 19, 1981; 49 FR 25796, June 22, 1984; 50 FR 51173, Dec. 13, 1985; 52 FR 46291, Dec. 4, 1987; 57 FR 35666, Aug. 10, 1992; 57 FR 42388, Sept. 14, 1992; 59 FR 41057, Aug. 10, 1994; 61 FR 56831, Nov. 4, 1996; 62 FR 1600, Jan. 10, 1997]
This subpart applies to all general industry workplaces. It covers all walking-working surfaces unless specifically excluded by an individual section of this subpart.
The following definitions apply in this subpart:
Alternating tread-type stair means a type of stairway consisting of a series of treads that usually are attached to a center support in an alternating manner such that an employee typically does not have both feet on the same level while using the stairway.
Anchorage means a secure point of attachment for equipment such as lifelines, lanyards, deceleration devices, and rope descent systems.
Authorized means an employee who the employer assigns to perform a specific type of duty, or allows in a specific location or area.
Cage means an enclosure mounted on the side rails of a fixed ladder or fastened to a structure behind the fixed ladder that is designed to surround the climbing space of the ladder. A cage also is called a “cage guard” or “basket guard.”
Carrier means the track of a ladder safety system that consists of a flexible cable or rigid rail attached to the fixed ladder or immediately adjacent to it.
Combination ladder means a portable ladder that can be used as a stepladder, extension ladder, trestle ladder, or stairway ladder. The components of a combination ladder also may be used separately as a single ladder.
Dangerous equipment means equipment, such as vats, tanks, electrical equipment, machinery, equipment or machinery with protruding parts, or other similar units, that, because of their function or form, may harm an employee who falls into or onto the equipment.
Designated area means a distinct portion of a walking-working surface delineated by a warning line in which employees may perform work without additional fall protection.
Dockboard means a portable or fixed device that spans a gap or compensates for a difference in elevation between a loading platform and a transport vehicle. Dockboards include, but are not limited to, bridge plates, dock plates, and dock levelers.
Equivalent means alternative designs, equipment, materials, or methods, that the employer can demonstrate will provide an equal or greater degree of safety for employees compared to the designs, equipment, materials, or methods specified in this subpart.
Extension ladder means a non-self-supporting portable ladder that is adjustable in length.
Failure means a load refusal, breakage, or separation of component parts. A load refusal is the point at which the ultimate strength of a component or object is exceeded.
Fall hazard means any condition on a walking-working surface that exposes an employee to a risk of harm from a fall on the same level or to a lower level.
Fall protection means any equipment, device, or system that prevents an employee from falling from an elevation or mitigates the effect of such a fall.
Fixed ladder means a ladder with rails or individual rungs that is permanently attached to a structure, building, or equipment. Fixed ladders include individual-rung ladders, but not ship stairs, step bolts, or manhole steps.
Grab bar means an individual horizontal or vertical handhold installed to provide access above the height of the ladder.
Guardrail system means a barrier erected along an unprotected or exposed side, edge, or other area of a walking-working surface to prevent employees from falling to a lower level.
Handrail means a rail used to provide employees with a handhold for support.
Hoist area means any elevated access opening to a walking-working surface through which equipment or materials are loaded or received.
Hole means a gap or open space in a floor, roof, horizontal walking-working surface, or similar surface that is at least 2 inches (5 cm) in its least dimension.
Individual-rung ladder means a ladder that has rungs individually attached to a building or structure. An individual-rung ladder does not include manhole steps.
Ladder means a device with rungs, steps, or cleats used to gain access to a different elevation.
Ladder safety system means a system designed to eliminate or reduce the possibility of falling from a ladder. A ladder safety system usually consists of a carrier, safety sleeve, lanyard, connectors, and body harness. Cages and wells are not ladder safety systems.
Low-slope roof means a roof that has a slope less than or equal to a ratio of 4 in 12 (vertical to horizontal).
Lower level means a surface or area to which an employee could fall. Such surfaces or areas include, but are not limited to, ground levels, floors, roofs, ramps, runways, excavations, pits, tanks, materials, water, equipment, and similar surfaces and structures, or portions thereof.
Manhole steps means steps that are individually attached to, or set into, the wall of a manhole structure.
Maximum intended load means the total load (weight and force) of all employees, equipment, vehicles, tools, materials, and other loads the employer reasonably anticipates to be applied to a walking-working surface at any one time.
Mobile means manually propelled or moveable.
Mobile ladder stand (ladder stand) means a mobile, fixed-height, self-supporting ladder that usually consists of wheels or casters on a rigid base and steps leading to a top step. A mobile ladder stand also may have handrails and is designed for use by one employee at a time.
Mobile ladder stand platform means a mobile, fixed-height, self-supporting unit having one or more standing platforms that are provided with means of access or egress.
Open riser means the gap or space between treads of stairways that do not have upright or inclined members (risers).
Opening means a gap or open space in a wall, partition, vertical walking-working surface, or similar surface that is at least 30 inches (76 cm) high and at least 18 inches (46 cm) wide, through which an employee can fall to a lower level.
Personal fall arrest system means a system used to arrest an employee in a fall from a walking-working surface. It consists of a body harness, anchorage, and connector. The means of connection may include a lanyard, deceleration device, lifeline, or a suitable combination of these.
Personal fall protection system means a system (including all components) an employer uses to provide protection from falling or to safely arrest an employee's fall if one occurs. Examples of personal fall protection systems include personal fall arrest systems, positioning systems, and travel restraint systems.
Platform means a walking-working surface that is elevated above the surrounding area.
Portable ladder means a ladder that can readily be moved or carried, and usually consists of side rails joined at intervals by steps, rungs, or cleats.
Positioning system (work-positioning system) means a system of equipment and connectors that, when used with a body harness or body belt, allows an employee to be supported on an elevated vertical surface, such as a wall or window sill, and work with both hands free. Positioning systems also are called “positioning system devices” and “work-positioning equipment.”
Qualified describes a person who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience has successfully demonstrated the ability to solve or resolve problems relating to the subject matter, the work, or the project.
Ramp means an inclined walking-working surface used to access another level.
Riser means the upright (vertical) or inclined member of a stair that is located at the back of a stair tread or platform and connects close to the front edge of the next higher tread, platform, or landing.
Rope descent system means a suspension system that allows an employee to descend in a controlled manner and, as needed, stop at any point during the descent. A rope descent system usually consists of a roof anchorage, support rope, a descent device, carabiner(s) or shackle(s), and a chair (seatboard). A rope descent system also is called controlled descent equipment or apparatus. Rope descent systems do not include industrial rope access systems.
Rung, step, or cleat means the cross-piece of a ladder on which an employee steps to climb up and down.
Runway means an elevated walking-working surface, such as a catwalk, a foot walk along shafting, or an elevated walkway between buildings.
Scaffold means any temporary elevated or suspended platform and its supporting structure, including anchorage points, used to support employees, equipment, materials, and other items. For purposes of this subpart, a scaffold does not include a crane-suspended or derrick-suspended personnel platform or a rope descent system.
Ship stair (ship ladder) means a stairway that is equipped with treads, stair rails, and open risers, and has a slope that is between 50 and 70 degrees from the horizontal.
Side-step ladder means a type of fixed ladder that requires an employee to step sideways from it in order to reach a walking-working surface, such as a landing.
Spiral stairs means a series of treads attached to a vertical pole in a winding fashion, usually within a cylindrical space.
Stair rail or stair rail system means a barrier erected along the exposed or open side of stairways to prevent employees from falling to a lower level.
Stairway (stairs) means risers and treads that connect one level with another, and includes any landings and platforms in between those levels. Stairways include standard, spiral, alternating tread-type, and ship stairs.
Standard stairs means a fixed or permanently installed stairway. Ship, spiral, and alternating tread-type stairs are not considered standard stairs.
Step bolt (pole step) means a bolt or rung attached at intervals along a structural member used for foot placement and as a handhold when climbing or standing.
Stepladder means a self-supporting, portable ladder that has a fixed height, flat steps, and a hinged back.
Stepstool means a self-supporting, portable ladder that has flat steps and side rails. For purposes of the final rule, stepstool includes only those ladders that have a fixed height, do not have a pail shelf, and do not exceed 32 inches (81 cm) in overall height to the top cap, although side rails may extend above the top cap. A stepstool is designed so an employee can climb and stand on all of the steps and the top cap.
Through ladder means a type of fixed ladder that allows the employee to step through the side rails at the top of the ladder to reach a walking-working surface, such as a landing.
Tieback means an attachment between an anchorage ( e.g., structural member) and a supporting device ( e.g., parapet clamp or cornice hook).
Toeboard means a low protective barrier that is designed to prevent materials, tools, and equipment from falling to a lower level, and protect employees from falling.
Travel restraint system means a combination of an anchorage, anchorage connector, lanyard (or other means of connection), and body support that an employer uses to eliminate the possibility of an employee going over the edge of a walking-working surface.
Tread means a horizontal member of a stair or stairway, but does not include landings or platforms.
Unprotected sides and edges mean any side or edge of a walking-working surface (except at entrances and other points of access) where there is no wall, guardrail system, or stair rail system to protect an employee from falling to a lower level.
Walking-working surface means any horizontal or vertical surface on or through which an employee walks, works, or gains access to a work area or workplace location.
Warning line means a barrier erected to warn employees that they are approaching an unprotected side or edge, and which designates an area in which work may take place without the use of other means of fall protection.
Well means a permanent, complete enclosure around a fixed ladder.
The employer must ensure:
The employer must ensure that each walking-working surface can support the maximum intended load for that surface.
The employer must provide, and ensure each employee uses, a safe means of access and egress to and from walking-working surfaces.
The employer must ensure that each ladder used meets the requirements of this section. This section covers all ladders, except when the ladder is:
The employer must ensure:
The employer must ensure:
The employer must ensure:
The employer must ensure:
The employer must ensure:
The employer must ensure:
[81 FR 82981, Nov. 18, 2016, as amended at 84 FR 68795, Dec. 17, 2019]
The employer must ensure:
This section covers all stairways (including standard, spiral, ship, and alternating tread-type stairs), except for articulated stairs (stairs that change pitch due to change in height at the point of attachment) such as those serving floating roof tanks, stairs on scaffolds, stairs designed into machines or equipment, and stairs on self-propelled motorized equipment.
The employer must ensure:
In addition to paragraph (b) of this section, the employer must ensure standard stairs:
In addition to paragraph (b) of this section, the employer must ensure spiral stairs:
In addition to paragraph (b) of this section, the employer must ensure ship stairs (see Figure D-9 of this section):
In addition to paragraph (b) of this section, the employer must ensure alternating tread-type stairs:
[81 FR 82981, Nov. 18, 2016, as amended at 84 FR 68795, Dec. 17, 2019]
The employer must ensure that each dockboard used meets the requirements of this section. The employer must ensure:
When the employer demonstrates there is no hazard of transfer vehicles running off the dockboard edge, the employer may use dockboards that do not have run-off protection.
Scaffolds used in general industry must meet the requirements in 29 CFR part 1926, subpart L (Scaffolds).
The employer must ensure:
[81 FR 82981, Nov. 18, 2016, as amended at 84 FR 68796, Dec. 17, 2019]
The employer must ensure:
The employer must ensure:
The employer must ensure:
The employer must ensure that each employee on a walking-working surface near an opening, including one with a chute attached, where the inside bottom edge of the opening is less than 39 inches (99 cm) above that walking-working surface and the outside bottom edge of the opening is 4 feet (1.2 m) or more above a lower level is protected from falling by the use of:
Each fixed ladder installed before November 19, 2018 is equipped with a personal fall arrest system, ladder safety system, cage, or well;
Each fixed ladder installed on and after November 19, 2018, is equipped with a personal fall arrest system or a ladder safety system;
When a fixed ladder, cage, or well, or any portion of a section thereof, is replaced, a personal fall arrest system or ladder safety system is installed in at least that section of the fixed ladder, cage, or well where the replacement is located; and
On and after November 18, 2036, all fixed ladders are equipped with a personal fall arrest system or a ladder safety system.
The employer must ensure:
The employer must ensure:
Except as provided elsewhere in this section or by other subparts of this part, the employer must ensure each employee on a walking-working surface 4 feet (1.2 m) or more above a lower level is protected from falling by:
When an employee is exposed to falling objects, the employer must ensure that each employee wears head protection that meets the requirements of subpart I of this part. In addition, the employer must protect employees from falling objects by implementing one or more of the following:
The employer must:
The employer must ensure guardrail systems meet the following requirements:
The employer must ensure each safety net system meets the requirements in 29 CFR part 1926, subpart M.
The employer must ensure each cover for a hole in a walking-working surface:
The employer must ensure:
The minimum clearance between handrails and any other object is 2.25 inches (5.7 cm).
Handrails and stair rail systems are smooth-surfaced to protect employees from injury, such as punctures or lacerations, and to prevent catching or snagging of clothing.
No opening in a stair rail system exceeds 19 inches (48 cm) at its least dimension.
Handrails have the shape and dimension necessary so that employees can grasp the handrail firmly.
The ends of handrails and stair rail systems do not present any projection hazards.
Handrails and the top rails of stair rail systems are capable of withstanding, without failure, a force of at least 200 pounds (890 N) applied in any downward or outward direction within 2 inches (5 cm) of any point along the top edge of the rail.
This paragraph (h) applies only to employers engaged in outdoor advertising operations (see § 1910.28(b)(10)). Employers must ensure that each employee who climbs a fixed ladder without fall protection:
The employer must ensure:
Body belts, harnesses, and other components used in personal fall arrest systems, work positioning systems, and travel restraint systems must meet the requirements of § 1910.140.
The employer must ensure each grab handle:
[81 FR 82981, Nov. 18, 2016, as amended at 84 FR 68796, Dec. 17, 2019]
The employer must retrain an employee when the employer has reason to believe the employee does not have the understanding and skill required by paragraphs (a) and (b) of this section. Situations requiring retraining include, but are not limited to, the following:
This section lists the sections and paragraph headings contained in §§ 1910.34 through 1910.39.
§ 1910.34 Coverage and definitions.
§ 1910.35 Compliance with Alternate Exit Route Codes.
§ 1910.36 Design and construction requirements for exit routes.
§ 1910.37 Maintenance, safeguards, and operational features for exit routes.
§ 1910.38 Emergency action plans.
§ 1910.39 Fire prevention plans.
[67 FR 67961, Nov. 7, 2002, as amended at 76 FR 33606, June 8, 2011]
Sections 1910.34 through 1910.39 apply to workplaces in general industry except mobile workplaces such as vehicles or vessels.
The rules in §§ 1910.34 through 1910.39 cover the minimum requirements for exit routes that employers must provide in their workplace so that employees may evacuate the workplace safely during an emergency. Sections 1910.34 through 1910.39 also cover the minimum requirements for emergency action plans and fire prevention plans.
Electroluminescent means a light-emitting capacitor. Alternating current excites phosphor atoms when placed between the electrically conductive surfaces to produce light. This light source is typically contained inside the device.
Exit means that portion of an exit route that is generally separated from other areas to provide a protected way of travel to the exit discharge. An example of an exit is a two-hour fire resistance-rated enclosed stairway that leads from the fifth floor of an office building to the outside of the building.
Exit access means that portion of an exit route that leads to an exit. An example of an exit access is a corridor on the fifth floor of an office building that leads to a two-hour fire resistance-rated enclosed stairway (the Exit).
Exit discharge means the part of the exit route that leads directly outside or to a street, walkway, refuge area, public way, or open space with access to the outside. An example of an exit discharge is a door at the bottom of a two-hour fire resistance-rated enclosed stairway that discharges to a place of safety outside the building.
Exit route means a continuous and unobstructed path of exit travel from any point within a workplace to a place of safety (including refuge areas). An exit route consists of three parts: The exit access; the exit; and, the exit discharge. (An exit route includes all vertical and horizontal areas along the route.)
High hazard area means an area inside a workplace in which operations include high hazard materials, processes, or contents.
Occupant load means the total number of persons that may occupy a workplace or portion of a workplace at any one time. The occupant load of a workplace is calculated by dividing the gross floor area of the workplace or portion of the workplace by the occupant load factor for that particular type of workplace occupancy. Information regarding the “Occupant load” is located in NFPA 101-2009, Life Safety Code, and in IFC-2009, International Fire Code (incorporated by reference, see § 1910.6).
Refuge area means either:
Self-luminous means a light source that is illuminated by a self-contained power source ( e.g., tritium) and that operates independently from external power sources. Batteries are not acceptable self-contained power sources. The light source is typically contained inside the device.
[67 FR 67961, Nov. 7, 2002, as amended at 76 FR 33606, June 8, 2011]
OSHA will deem an employer demonstrating compliance with the exit-route provisions of NFPA 101, Life Safety Code, 2009 edition, or the exit-route provisions of the International Fire Code, 2009 edition, to be in compliance with the corresponding requirements in §§ 1910.34, 1910.36, and 1910.37 (incorporated by reference, see section § 1910.6).
[76 FR 33606, June 8, 2011]
Exit routes must meet the following design and construction requirements:
At least two exit routes must be available in a workplace to permit prompt evacuation of employees and other building occupants during an emergency, except as allowed in paragraph (b)(3) of this section. The exit routes must be located as far away as practical from each other so that if one exit route is blocked by fire or smoke, employees can evacuate using the second exit route.
More than two exit routes must be available in a workplace if the number of employees, the size of the building, its occupancy, or the arrangement of the workplace is such that all employees would not be able to evacuate safely during an emergency.
A single exit route is permitted where the number of employees, the size of the building, its occupancy, or the arrangement of the workplace is such that all employees would be able to evacuate safely during an emergency.
Each outdoor exit route must meet the minimum height and width requirements for indoor exit routes and must also meet the following requirements:
[67 FR 67961, Nov. 7, 2002, as amended at 76 FR 33606, June 8, 2011]
[67 FR 67961, Nov. 7, 2002]
An employer must have an emergency action plan whenever an OSHA standard in this part requires one. The requirements in this section apply to each such emergency action plan.
An emergency action plan must be in writing, kept in the workplace, and available to employees for review. However, an employer with 10 or fewer employees may communicate the plan orally to employees.
An emergency action plan must include at a minimum:
An employer must have and maintain an employee alarm system. The employee alarm system must use a distinctive signal for each purpose and comply with the requirements in § 1910.165.
An employer must designate and train employees to assist in a safe and orderly evacuation of other employees.
An employer must review the emergency action plan with each employee covered by the plan:
[67 FR 67961, Nov. 7, 2002]
An employer must have a fire prevention plan when an OSHA standard in this part requires one. The requirements in this section apply to each such fire prevention plan.
A fire prevention plan must be in writing, be kept in the workplace, and be made available to employees for review. However, an employer with 10 or fewer employees may communicate the plan orally to employees.
A fire prevention plan must include:
An employer must inform employees upon initial assignment to a job of the fire hazards to which they are exposed. An employer must also review with each employee those parts of the fire prevention plan necessary for self-protection.
[67 FR 67961, Nov. 7, 2002]
This appendix serves as a nonmandatory guideline to assist employers in complying with the appropriate requirements of subpart E.
§ 1910.38 Employee emergency plans.
1. Emergency action plan elements. The emergency action plan should address emergencies that the employer may reasonably expect in the workplace. Examples are: fire; toxic chemical releases; hurricanes; tornadoes; blizzards; floods; and others. The elements of the emergency action plan presented in paragraph 1910.38(c) can be supplemented by the following to more effectively achieve employee safety and health in an emergency. The employer should list in detail the procedures to be taken by those employees who have been selected to remain behind to care for essential plant operations until their evacuation becomes absolutely necessary. Essential plant operations may include the monitoring of plant power supplies, water supplies, and other essential services which cannot be shut down for every emergency alarm. Essential plant operations may also include chemical or manufacturing processes which must be shut down in stages or steps where certain employees must be present to assure that safe shut down procedures are completed.
The use of floor plans or workplace maps which clearly show the emergency escape routes should be included in the emergency action plan. Color coding will aid employees in determining their route assignments.
The employer should also develop and explain in detail what rescue and medical first aid duties are to be performed and by whom. All employees are to be told what actions they are to take in these emergency situations that the employer anticipates may occur in the workplace.
2. Emergency evacuation. At the time of an emergency, employees should know what type of evacuation is necessary and what their role is in carrying out the plan. In some cases where the emergency is very grave, total and immediate evacuation of all employees is necessary. In other emergencies, a partial evacuation of nonessential employees with a delayed evacuation of others may be necessary for continued plant operation. In some cases, only those employees in the immediate area of the fire may be expected to evacuate or move to a safe area such as when a local application fire suppression system discharge employee alarm is sounded. Employees must be sure that they know what is expected of them in all such emergency possibilities which have been planned in order to provide assurance of their safety from fire or other emergency.
The designation of refuge or safe areas for evacuation should be determined and identified in the plan. In a building divided into fire zones by fire walls, the refuge area may still be within the same building but in a different zone from where the emergency occurs.
Exterior refuge or safe areas may include parking lots, open fields or streets which are located away from the site of the emergency and which provide sufficient space to accommodate the employees. Employees should be instructed to move away from the exit discharge doors of the building, and to avoid congregating close to the building where they may hamper emergency operations.
3. Emergency action plan training. The employer should assure that an adequate number of employees are available at all times during working hours to act as evacuation wardens so that employees can be swiftly moved from the danger location to the safe areas. Generally, one warden for each twenty employees in the workplace should be able to provide adequate guidance and instruction at the time of a fire emergency. The employees selected or who volunteer to serve as wardens should be trained in the complete workplace layout and the various alternative escape routes from the workplace. All wardens and fellow employees should be made aware of handicapped employees who may need extra assistance, such as using the buddy system, and of hazardous areas to be avoided during emergencies. Before leaving, wardens should check rooms and other enclosed spaces in the workplace for employees who may be trapped or otherwise unable to evacuate the area.
After the desired degree of evacuation is completed, the wardens should be able to account for or otherwise verify that all employees are in the safe areas.
In buildings with several places of employment, employers are encouraged to coordinate their plans with the other employers in the building. A building-wide or standardized plan for the whole building is acceptable provided that the employers inform their respective employees of their duties and responsibilities under the plan. The standardized plan need not be kept by each employer in the multi-employer building, provided there is an accessible location within the building where the plan can be reviewed by affected employees. When multi-employer building-wide plans are not feasible, employers should coordinate their plans with the other employers within the building to assure that conflicts and confusion are avoided during times of emergencies. In multi-story buildings where more than one employer is on a single floor, it is essential that these employers coordinate their plans with each other to avoid conflicts and confusion.
4. Fire prevention housekeeping. The standard calls for the control of accumulations of flammable and combustible waste materials.
It is the intent of this standard to assure that hazardous accumulations of combustible waste materials are controlled so that a fast developing fire, rapid spread of toxic smoke, or an explosion will not occur. This does not necessarily mean that each room has to be swept each day. Employers and employees should be aware of the hazardous properties of materials in their workplaces, and the degree of hazard each poses. Certainly oil soaked rags have to be treated differently than general paper trash in office areas. However, large accumulations of waste paper or corrugated boxes, etc., can pose a significant fire hazard. Accumulations of materials which can cause large fires or generate dense smoke that are easily ignited or may start from spontaneous combustion, are the types of materials with which this standard is concerned. Such combustible materials may be easily ignited by matches, welder's sparks, cigarettes and similar low level energy ignition sources.
5. Maintenance of equipment under the fire prevention plan. Certain equipment is often installed in workplaces to control heat sources or to detect fuel leaks. An example is a temperature limit switch often found on deep-fat food fryers found in restaurants. There may be similar switches for high temperature dip tanks, or flame failure and flashback arrester devices on furnaces and similar heat producing equipment. If these devices are not properly maintained or if they become inoperative, a definite fire hazard exists. Again employees and supervisors should be aware of the specific type of control devices on equipment involved with combustible materials in the workplace and should make sure, through periodic inspection or testing, that these controls are operable. Manufacturers' recommendations should be followed to assure proper maintenance procedures.
[45 FR 60714, Sept. 12, 1980]
This section covers powered platform installations permanently dedicated to interior or exterior building maintenance of a specific structure or group of structures. This section does not apply to suspended scaffolds (swinging scaffolds) used to service buildings on a temporary basis and covered under subpart D of this part, nor to suspended scaffolds used for construction work and covered under subpart L of 29 CFR part 1926. Building maintenance includes, but is not limited to, such tasks as window cleaning, caulking, metal polishing and reglazing.
This section applies to all permanent installations completed after July 23, 1990. Major modifications to existing installations completed after that date are also considered new installations under this section.
Anemometer means an instrument for measuring wind velocity.
Angulated roping means a suspension method where the upper point of suspension is inboard from the attachments on the suspended unit, thus causing the suspended unit to bear against the face of the building.
Building face roller means a rotating cylindrical member designed to ride on the face of the building wall to prevent the platform from abrading the face of the building and to assist in stabilizing the platform.
Building maintenance means operations such as window cleaning, caulking, metal polishing, reglazing, and general maintenance on building surfaces.
Cable means a conductor, or group of conductors, enclosed in a weatherproof sheath, that may be used to supply electrical power and/or control current for equipment or to provide voice communication circuits.
Carriage means a wheeled vehicle used for the horizontal movement and support of other equipment.
Certification means a written, signed and dated statement confirming the performance of a requirement of this section.
Combination cable means a cable having both steel structural members capable of supporting the platform, and copper or other electrical conductors insulated from each other and the structural members by nonconductive barriers.
Competent person means a person who, because of training and experience, is capable of identifying hazardous or dangerous conditions in powered platform installations and of training employees to identify such conditions.
Continuous pressure means the need for constant manual actuation for a control to function.
Control means a mechanism used to regulate or guide the operation of the equipment.
Davit means a device, used singly or in pairs, for suspending a powered platform from work, storage and rigging locations on the building being serviced. Unlike outriggers, a davit reacts its operating load into a single roof socket or carriage attachment.
Equivalent means alternative designs, materials or methods which the employer can demonstrate will provide an equal or greater degree of safety for employees than the methods, materials or designs specified in the standard.
Ground rigging means a method of suspending a working platform starting from a safe surface to a point of suspension above the safe surface.
Ground rigged davit means a davit which cannot be used to raise a suspended working platform above the building face being serviced.
Guide button means a building face anchor designed to engage a guide track mounted on a platform.
Guide roller means a rotating cylindrical member, operating separately or as part of a guide assembly, designed to provide continuous engagement between the platform and the building guides or guideways.
Guide shoe means a device attached to the platform designed to provide a sliding contact between the platform and the building guides.
Hoisting machine means a device intended to raise and lower a suspended or supported unit.
Hoist rated load means the hoist manufacturer's maximum allowable operating load.
Installation means all the equipment and all affected parts of a building which are associated with the performance of building maintenance using powered platforms.
Interlock means a device designed to ensure that operations or motions occur in proper sequence.
Intermittent stabilization means a method of platform stabilization in which the angulated suspension wire rope(s) are secured to regularly spaced building anchors.
Lanyard means a flexible line of rope, wire rope or strap which is used to secure the body belt or body harness to a deceleration device, lifeline or anchorage.
Lifeline means a component consisting of a flexible line for connection to an anchorage at one end to hang vertically (vertical lifeline), or for connection to anchorages at both ends to stretch horizontally (horizontal lifeline), and which serves as a means for connecting other components of a personal fall arrest system to the anchorage.
Live load means the total static weight of workers, tools, parts, and supplies that the equipment is designed to support.
Obstruction detector means a control that will stop the suspended or supported unit in the direction of travel if an obstruction is encountered, and will allow the unit to move only in a direction away from the obstruction.
Operating control means a mechanism regulating or guiding the operation of equipment that ensures a specific operating mode.
Operating device means a device actuated manually to activate a control.
Outrigger means a device, used singly or in pairs, for suspending a working platform from work, storage, and rigging locations on the building being serviced. Unlike davits, an outrigger reacts its operating moment load as at least two opposing vertical components acting into two or more distinct roof points and/or attachments.
Platform rated load means the combined weight of workers, tools, equipment and other material which is permitted to be carried by the working platform at the installation, as stated on the load rating plate.
Poured socket means the method of providing wire rope terminations in which the ends of the rope are held in a tapered socket by means of poured spelter or resins.
Primary brake means a brake designed to be applied automatically whenever power to the prime mover is interrupted or discontinued.
Prime mover means the source of mechanical power for a machine.
Rated load means the manufacturer's recommended maximum load.
Rated strength means the strength of wire rope, as designated by its manufacturer or vendor, based on standard testing procedures or acceptable engineering design practices.
Rated working load means the combined static weight of men, materials, and suspended or supported equipment.
Registered professional engineer means a person who has been duly and currently registered and licensed by an authority within the United States or its territories to practice the profession of engineering.
Roof powered platform means a working platform where the hoist(s) used to raise or lower the platform is located on the roof.
Roof rigged davit means a davit used to raise the suspended working platform above the building face being serviced. This type of davit can also be used to raise a suspended working platform which has been ground-rigged.
Rope means the equipment used to suspend a component of an equipment installation, i.e., wire rope.
Safe surface means a horizontal surface intended to be occupied by personnel, which is so protected by a fall protection system that it can be reasonably assured that said occupants will be protected against falls.
Secondary brake means a brake designed to arrest the descent of the suspended or supported equipment in the event of an overspeed condition.
Self powered platform means a working platform where the hoist(s) used to raise or lower the platform is mounted on the platform.
Speed reducer means a positive type speed reducing machine.
Stability factor means the ratio of the stabilizing moment to the overturning moment.
Stabilizer tie means a flexible line connecting the building anchor and the suspension wire rope supporting the platform.
Supported equipment means building maintenance equipment that is held or moved to its working position by means of attachment directly to the building or extensions of the building being maintained.
Suspended equipment means building maintenance equipment that is suspended and raised or lowered to its working position by means of ropes or combination cables attached to some anchorage above the equipment.
Suspended scaffold (swinging scaffold) means a scaffold supported on wire or other ropes, used for work on, or for providing access to, vertical sides of structures on a temporary basis. Such scaffold is not designed for use on a specific structure or group of structures.
Tail line means the nonsupporting end of the wire rope used to suspend the platform.
Tie-in guides means the portion of a building that provides continuous positive engagement between the building and a suspended or supported unit during its vertical travel on the face of the building.
Traction hoist means a type of hoisting machine that does not accumulate the suspension wire rope on the hoisting drum or sheave, and is designed to raise and lower a suspended load by the application of friction forces between the suspension wire rope and the drum or sheave.
Transportable outriggers means outriggers designed to be moved from one work location to another.
Trolley carriage means a carriage suspended from an overhead track structure.
Verified means accepted by design, evaluation, or inspection by a registered professional engineer.
Weatherproof means so constructed that exposure to adverse weather conditions will not affect or interfere with the proper use or functions of the equipment or component.
Winding drum hoist means a type of hoisting machine that accumulates the suspension wire rope on the hoisting drum.
Working platform means suspended or supported equipment intended to provide access to the face of a building and manned by persons engaged in building maintenance.
Wrap means one complete turn of the suspension wire rope around the surface of a hoist drum.
The following requirements apply to affected parts of buildings which utilize working platforms for building maintenance.
The system shall keep the equipment in continuous contact with the building facade, and shall prevent sudden horizontal movement of the platform. The system may be used together with continuous positive building guide systems using tie-in guides on the same building, provided the requirements for each system are met.
The system shall keep the equipment in continuous contact with the building facade, and shall prevent sudden horizontal movement of the platform. This system is acceptable only where the suspended portion of the equipment in use does not exceed 130 feet (39.6 m) above a safe surface or ground level, and where the platform maintains no less than 10 pounds (44.4 n) angulation force on the building facade.
Operational areas for trackless type equipment shall be provided with structural stops, such as curbs, to prevent equipment from traveling outside its intended travel areas and to prevent a crushing or shearing hazard.
Means shall be provided to traverse all carriages and their suspended equipment to a safe area for maintenance and storage.
Imbedded tie-down anchors, fasteners, and affected structures shall be resistant to corrosion.
A written emergency action plan shall be developed and implemented for each kind of working platform operation. This plan shall explain the emergency procedures which are to be followed in the event of a power failure, equipment failure or other emergencies which may be encountered. The plan shall also explain that employees inform themselves about the building emergency escape routes, procedures and alarm systems before operating a platform. Upon initial assignment and whenever the plan is changed the employer shall review with each employee those parts of the plan which the employee must know to protect himself or herself in the event of an emergency.
Repairs or major maintenance of those building portions that provide primary support for the suspended equipment shall not affect the capability of the building to meet the requirements of this standard.
The following electrical requirements apply to buildings which utilize working platforms for building maintenance.
The following requirements apply to equipment which are part of a powered platform installation, such as platforms, stabilizing components, carriages, outriggers, davits, hoisting machines, wire ropes and electrical components.
Bolted connections shall be self-locking or shall otherwise be secured to prevent loss of the connections by vibration.
Elevated building maintenance equipment shall be suspended by a carriage, outriggers, davits or an equivalent method.
Carriages used for suspension of elevated building maintenance equipment shall comply with the following:
Where:
F = Design factor
S = Manufacturer's rated strength of one suspension rope
N = Number of suspension ropes under load
W = Rated working load on all ropes at any point of travel
All completed building maintenance equipment installations shall be inspected and tested in the field before being placed in initial service to determine that all parts of the installation conform to applicable requirements of this standard, and that all safety and operating equipment is functioning as required. A similar inspection and test shall be made following any major alteration to an existing installation. No hoist in an installation shall be subjected to a load in excess of 125 percent of its rated load.
Before lowering personnel below the top elevation of the building, the hoist shall be tested each day in the lifting direction with the intended load to make certain it has sufficient capacity to raise the personnel back to the boarding level.
All parts of the equipment affecting safe operation shall be maintained in proper working order so that they may perform the functions for which they were intended. The equipment shall be taken out of service when it is not in proper working order.
The hoisting ropes shall be reshackled at the nondrum ends at intervals not exceeding 24 months. When reshackling the ropes, a sufficient length shall be cut from the end of the rope to remove damaged or fatigued portions.
Roof track systems, tie-downs, or similar equipment shall be maintained in proper working order so that they perform the function for which they were intended.
T-rails, indented mullions, or equivalent guides located in the face of a building shall be maintained in proper working order so that they perform the functions for which they were intended. Brackets for cable stabilizers shall similarly be maintained in proper working order.
No person shall render a required safety device or electrical protective device inoperative, except as necessary for tests, inspections, and maintenance. Immediately upon completion of such tests, inspections and maintenance, the device shall be restored to its normal operating condition.
Employees on working platforms shall be protected by a personal fall arrest system meeting the requirements of subpart I of this part and as otherwise provided by this standard.
Appendix D to § 1910.66—Existing Installations (Mandatory)
Use of the Appendix
Appendix D sets out the mandatory building and equipment requirements for applicable permanent installations completed after August 27, 1971, and no later than July 23, 1990 which are exempt from the paragraphs (a), (b)(1), (b)(2), (c), (d), (e), and (f) of this standard. The requirements in appendix D are essentially the same as unrevised building and equipment provisions which previously were designated as 29 CFR 1910.66 (a), (b), (c) and (d) and which were effective on August 27, 1971.
A system of platform suspension in which the upper wire rope sheaves or suspension points are closer to the plane of the building face than the corresponding attachment points on the platform, thus causing the platform to press against the face of the building during its vertical travel.
American National Standards Institute.
The method of providing wire rope attachments in which the ends of the wire strands are bent back and are held in a tapered socket by means of poured molten babbitt metal.
A brake in which the holding effect is obtained by frictional resistance between one or more faces of discs keyed to the rotating member to be held and fixed discs keyed to the stationary or housing member (pressure between the discs being applied axially).
An essentially undirectional brake in which the holding effect is obtained by the snubbing action of a flexible band wrapped about a cylindrical wheel or drum affixed to the rotating member to be held, the connections and linkages being so arranged that the motion of the brake wheel or drum will act to increase the tension or holding force of the band.
A brake in which the holding effect is obtained by applying the direct pressure of two or more segmental friction elements held to a stationary member against a cylindrical wheel or drum affixed to the rotating member to be held.
A specialized form of guide roller designed to contact a portion of the outer face or wall structure of the building, and to assist in stabilizing the operators' platform during vertical travel.
Operation by means of buttons or switches, any one of which may be used to control the movement of the working platform or roof car, only as long as the button or switch is manually maintained in the actuating position.
A system governing starting, stopping, direction, acceleration, speed, and retardation of moving members.
A device or group of devices, usually contained in a single enclosure, which serves to control in some predetermined manner the apparatus to which it is connected.
A conducting connection between an electrical circuit or equipment and the earth, or some conducting body which serves in place of the earth.
A rotating, bearing-mounted, generally cylindrical member, operating separately or as part of a guide shoe assembly, attached to the platform, and providing rolling contact with building guideways, or other building contact members.
An assembly of rollers, slide members, or the equivalent, attached as a unit to the operators' platform, and designed to engage with the building members provided for the vertical guidance of the operators' platform.
A device actuated by the operation of some other device with which it is directly associated, to govern succeeding operations of the same or allied devices.
A pushbutton, lever, or other manual device used to actuate a control.
Equipment to provide access to the exterior of a building for maintenance, consisting of a suspended power-operated working platform, a roof car, or other suspension means, and the requisite operating and control devices.
The combined weight of employees, tools, equipment, and other material which the working platform is designed and installed to lift.
An electrically energized contactor responsive to an initiating control circuit, which in turn causes a moving member to travel in a particular direction.
A structure for the suspension of a working platform, providing for its horizontal movement to working positions.
A powered platform having the raising and lowering mechanism located on a roof car.
A powered platform having the raising and lowering mechanism located on the working platform.
A cable made up of electrical or communication conductors or both, and providing electrical connection between the working platform and the roof car or other fixed point.
Equipment so constructed or protected that exposure to the weather will not interfere with its proper operation.
The suspended structure arranged for vertical travel which provides access to the exterior of the building or structure.
The stress at which the material exhibits a permanent set of 0.2 percent.
The method of providing wire rope attachments in which the splayed or fanned wire ends are held in a tapered socket by means of poured molten zinc.
All powered platform installations for exterior building maintenance completed as of August 27, 1971, but no later than [insert date, 180 days after the effective date], shall meet all of the design, construction and installation requirements of part II and III of the “American National Standard Safety Requirements for Powered Platforms for Exterior Building Maintenance ANSI A120.1-1970” and of this appendix. References shall be made to appropriate parts of ANSI A120.1-1970 for detail specifications for equipment and special installations.
The requirements of this appendix apply only to electric powered platforms. It is not the intent of this appendix to prohibit the use of other types of power. Installation of powered platforms using other types of power is permitted, provided such platforms have adequate protective devices for the type of power used, and otherwise provide for reasonable safety of life and limb to users of equipment and to others who may be exposed.
Roof car stability shall be determined by either paragraph (c)(3) (i) or (ii) of this appendix, whichever is greater.
Safe access to the roof car and from the roof car to the working platform shall be provided. If the access to the roof car at any point of its travel is not over the roof area or where otherwise necessary for safety, then self-closing, self-locking gates shall be provided. Access to and from roof cars must comply with the requirements of subpart D of this part.
The working platform shall be of girder or truss construction and shall be adequate to support its rated load under any position of loading, and comply with the provisions set forth in section 10 of ANSI A120.1-1970, American National Standard Safety Requirements for Powered Platforms for Exterior Building Maintenance.
Each working platform shall bear a manufacturer's load rating plate, conspicuously posted; stating the maximum permissible rated load. Load rating plates shall be made of noncorrosive material and shall have letters and figures stamped, etched, or cast on the surface. The minimum height of the letters and figures shall be one-fourth inch.
The working platform shall have a minimum net width of 24 inches.
Working platforms shall be furnished with permanent guard rails not less than 36 inches high, and not more than 42 inches high at the front (building side). At the rear, and on the sides, the rail shall not be less than 42 inches high. An intermediate guardrail shall be provided around the entire platform between the top guardrail and the toeboard.
A four-inch toeboard shall be provided along all sides of the working platform.
The spaces between the intermediate guardrail and platform toeboard on the building side of the working platform, and between the top guardrail and the toeboard on other sides of the platform, shall be filled with metalic mesh or similar material that will reject a ball one inch in diameter. The installed mesh shall be capable of withstanding a load of 100 pounds applied horizontally over any area of 144 square inches. If the space between the platform and the building face does not exceed eight inches, and the platform is restrained by guides, the mesh may be omitted on the front side.
The platform flooring shall be of the nonskid type, and if of open construction, shall reject a 9/16 -inch diameter ball, or be provided with a screen below the floor to reject a 9/16 -inch diameter ball.
Where access gates are provided, they shall be self-closing and self-locking.
Emergency operation of the main drive machine may be provided to allow manual cranking. This provision for manual operation shall be designed so that not more than two persons will be required to perform this operation. The access to this provision shall include a means to automatically make the machine inoperative electrically while under the emergency manual operation. The design shall be such that the emergency brake is operative at or below governor tripping speed during manual operation.
The hoisting machine(s) shall have two independent braking means, each designed to stop and hold the working platform with 125 percent of rated load.
F = S × N/W
Where
S = Manufacturer's rated breaking strength of one rope.
N = Number of ropes under load.
W = Maximum static load on all ropes with the platform and its rated load at any point of its travel.
The requirements of paragraphs (c)(1) through (c)(5) of this appendix shall apply to Type T powered platforms.
The requirements of paragraphs (c)(6) through (c)(16) of this appendix apply to Type T powered platforms.
The requirements of paragraphs (c) (17) and (18) of this appendix shall apply to Type T powered platforms.
Brakes requirements of paragraph (c)(19) of this appendix shall apply.
All the requirements of paragraph (c)(23) of this appendix shall apply to Type T powered platforms.
[54 FR 31456, July 28, 1989, as amended at 61 FR 9235, Mar. 7, 1996; 72 FR 7190, Feb. 14, 2007; 81 FR 82998, Nov. 18, 2016]
Any vehicle—mounted device, telescoping or articulating, or both, which is used to position personnel.
An aerial device consisting of a single- or multiple-section extensible ladder.
An aerial device with two or more hinged boom sections.
An aerial device (except ladders) with a telescopic or extensible boom. Telescopic derricks with personnel platform attachments shall be considered to be extensible boom platforms when used with a personnel platform.
An aerial device designed for work on energized lines and apparatus.
A combination of an aerial device, its vehicle, and related equipment.
Any personnel-carrying device (basket or bucket) which is a component of an aerial device.
Any carrier that is not manually propelled.
An aerial device designed to elevate a platform in a substantially vertical axis.
Before the truck is moved for highway travel, aerial ladders shall be secured in the lower traveling position by the locking device above the truck cab, and the manually operated device at the base of the ladder, or by other equally effective means (e.g., cradles which prevent rotation of the ladder in combination with positive acting linear actuators).
Electrical tests shall be made in conformance with the requirements of ANSI A92.2—1969, Section 5. However, equivalent DC voltage tests may be used in lieu of the AC voltage test specified in A92.2—1969. DC voltage tests which are approved by the equipment manufacturer or equivalent entity shall be considered an equivalent test for the purpose of this paragraph (c)(3).
All critical hydraulic and pneumatic components shall comply with the provisions of the American National Standards Institute standard, ANSI A92.2—1969, Section 4.9 Bursting Safety Factor. Critical components are those in which a failure would result in a free fall or free rotation of the boom. All noncritical components shall have a bursting safety factor of at least two to one.
[39 FR 23502, June 27, 1974, as amended at 40 FR 13439, Mar. 26, 1975; 55 FR 32014, Aug. 6, 1990; 61 FR 9235, Mar. 7, 1996; 79 FR 37190, July 1, 2014; 81 FR 82999, Nov. 18, 2016]
A handhold is a device attached to the belt which can be grasped by the passenger to provide a means of maintaining balance.
One which has a handgrip surface fully exposed and capable of being encircled by the passenger's fingers.
A cup-shaped device, open at the top in the direction of travel of the step for which it is to be used, and closed at the bottom, into which the passenger may place his fingers.
A device, the purpose of which is to cut off the power to the motor and apply the brake to stop the carrier in the event that a loaded step passes the terminal landing.
A device consisting of a power-driven endless belt moving in one direction only, and provided with steps or platforms and handholds attached to it for the transportation of personnel from floor to floor.
Rated speed is the speed for which the device is designed and installed.
An electric limit switch operated mechanically by the rollers on the manlift steps. It consists of an additional hinged or “split” rail, mounted on the regular guide rail, over which the step rollers pass. It is springloaded in the “split” position. If the step supports no load, the rollers will “bump” over the switch; if a loaded step should pass over the section, the split rail will be forced straight, tripping the switch and opening the electrical circuit.
A step is a passenger carrying unit.
The travel is the distance between the centers of the top and bottom pulleys.
This section applies to the construction, maintenance, inspection, and operation of manlifts in relation to accident hazards. Manlifts covered by this section consist of platforms or brackets and accompanying handholds mounted on, or attached to an endless belt, operating vertically in one direction only and being supported by, and driven through pulleys, at the top and bottom. These manlifts are intended for conveyance of persons only. It is not intended that this section cover moving stairways, elevators with enclosed platforms (“Paternoster” elevators), gravity lifts, nor conveyors used only for conveying material. This section applies to manlifts used to carry only personnel trained and authorized by the employer in their use.
The purpose of this section is to provide reasonable safety for life and limb.
All new manlift installations and equipment installed after the effective date of these regulations shall meet the design requirements of the “American National Safety Standard for Manlifts ANSI A90.1-1969”, which is incorporated by reference as specified in § 1910.6, and the requirements of this section.
The following codes and subparts of this part are applicable to this section: Safety Code for Mechanical Power Transmission Apparatus, ANSI B15.1-1953 (R 1958); Safety Code for Fixed Ladders, ANSI A14.3-1956; and subparts D, O, and S. The preceding ANSI standards are incorporated by reference as specified in § 1910.6.
Floor openings for both the “up” and “down” runs shall be not less than 28 inches nor more than 36 inches in width for a 12-inch belt; not less than 34 inches nor more than 38 inches for a 14-inch belt; and not less than 36 inches nor more than 40 inches for a 16-inch belt and shall extend not less than 24 inches, nor more than 28 inches from the face of the belt.
All floor openings for a given manlift shall be uniform in size and shall be approximately circular, and each shall be located vertically above the opening below it.
The clearanace between the floor or mounting platform and the lower edge for the conical guard above it required by subparagraph (7) of this paragraph shall not be less than 7 feet 6 inches. Where this clearance cannot be obtained no access to the manlift shall be provided and the manlift runway shall be enclosed where it passes through such floor.
The landing space adjacent to the floor openings shall be free from obstruction and kept clear at all times. This landing space shall be at least 2 feet in width from the edge of the floor opening used for mounting and dismounting.
Adequate lighting, not less than 5-foot candles, shall be provided at each floor landing at all times when the lift is in operation.
The landing surfaces at the entrances and exits to the manlift shall be constructed and maintained as to provide safe footing at all times.
Where there is a travel of 50 feet or more between floor landings, one or more emergency landings shall be provided so that there will be a landing (either floor or emergency) for every 25 feet or less of manlift travel.
On the ascending side of the manlift floor openings shall be provided with a bevel guard or cone meeting the following requirements:
In lieu of the fixed guards specified in subdivision (i) of this subparagraph a floating type safety cone may be used, such floating cones to be mounted on hinges at least 6 inches below the underside of the floor and so constructed as to actuate a limit switch should a force of 2 pounds be applied on the edge of the cone closest to the hinge. The depth of this floating cone need not exceed 12 inches.
The entrances and exits at all floor landings affording access to the manlift shall be guarded by a maze (staggered railing) or a handrail equipped with self-closing gates.
The rails shall be standard guardrails with toeboards that meet the requirements in subpart D of this part.
Gates, if used, shall open outward and shall be self-closing. Corners of gates shall be rounded.
Maze or staggered openings shall offer no direct passage between enclosure and outer floor space.
The floor opening at each landing shall be guarded on sides not used for entrance or exit by a wall, a railing and toeboard or by panels of wire mesh of suitable strength.
Such rails or guards shall be at least 42 inches in height on the up-running side and 66 inches on the down-running side.
At the bottom landing the clear area shall be not smaller than the area enclosed by the guardrails on the floors above, and any wall in front of the down-running side of the belt shall be not less than 48 inches from the face of the belt. This space shall not be encroached upon by stairs or ladders.
The lower (boot) pulley shall be installed so that it is supported by the lowest landing served. The sides of the pulley support shall be guarded to prevent contact with the pulley or the steps.
A mounting platform shall be provided in front or to one side of the uprun at the lowest landing, unless the floor level is such that the following requirement can be met: The floor or platform shall be at or above the point at which the upper surface of the ascending step completes its turn and assumes a horizontal position.
To guard against persons walking under a descending step, the area on the downside of the manlift shall be guarded in accordance with subparagraph (8) of this paragraph. To guard against a person getting between the mounting platform and an ascending step, the area between the belt and the platform shall be protected by a guardrail.
A top clearance shall be provided of at least 11 feet above the top terminal landing. This clearance shall be maintained from a plane through each face of the belt to a vertical cylindrical plane having a diameter 2 feet greater than the diameter of the floor opening, extending upward from the top floor to the ceiling on the up-running side of the belt. No encroachment of structural or machine supporting members within this space will be permitted.
An emergency grab bar or rail and platform shall be provided at the head pulley when the distance to the head pulley is over 6 feet above the top landing, otherwise only a grab bar or rail is to be provided to permit the rider to swing free should the emergency stops become inoperative.
A fixed metal ladder accessible from both the “up” and “down” run of the manlift shall be provided for the entire travel of the manlift. Such ladders shall meet the requirements in subpart D of this part.
Manlift rails shall be secured in such a manner as to avoid spreading, vibration, and misalinement.
Both runs of the manlift shall be illuminated at all times when the lift is in operation. An intensity of not less than 1-foot candle shall be maintained at all points. (However, see subparagraph (6)(iii) of this paragraph for illumination requirements at landings.)
Lighting of manlift runways shall be by means of circuits permanently tied in to the building circuits (no switches), or shall be controlled by switches at each landing. Where separate switches are provided at each landing, any switch shall turn on all lights necessary to illuminate the entire runway.
The entire manlift and its driving mechanism shall be protected from the weather at all times.
Brakes provided for stopping and holding a manlift shall be inherently self-engaging, by requiring power or force from an external source to cause disengagement. The brake shall be electrically released, and shall be applied to the motor shaft for direct-connected units or to the input shaft for belt-driven units. The brake shall be capable of stopping and holding the manlift when the descending side is loaded with 250 lb on each step.
No manlift designed for a speed in excess of 80 feet per minute shall be installed.
Steps or platforms shall be not less than 12 inches nor more than 14 inches deep, measured from the belt to the edge of the step or platform.
The width of the step or platform shall be not less than the width of the belt to which it is attached.
The distance between steps shall be equally spaced and not less than 16 feet measured from the upper surface of one step to the upper surface of the next step above it.
The surface of the step shall make approximately a right angle with the “up” and “down” run of the belt, and shall travel in the approximate horizontal position with the “up” and “down” run of the belt.
The upper or working surfaces of the step shall be of a material having inherent nonslip characteristics (coefficient of friction not less than 0.5) or shall be covered completely by a nonslip tread securely fastened to it.
When subjected to a load of 400 pounds applied at the approximate center of the step, step frames, or supports and their guides shall be of adequate strength to:
No steps shall be provided unless there is a corresponding handhold above or below it meeting the requirements of paragraph (c)(4) of this section. If a step is removed for repairs or permanently, the handholds immediately above and below it shall be removed before the lift is again placed in service.
Handholds attached to the belt shall be provided and installed so that they are not less than 4 feet nor more than 4 feet 8 inches above the step tread. These shall be so located as to be available on the both “up” and “down” run of the belt.
The grab surface of the handhold shall be not less than 4 1/2 inches in width, not less than 3 inches in depth, and shall provide 2 inches of clearance from the belt. Fastenings for handholds shall be located not less than 1 inch from the edge of the belt.
The handhold shall be capable of withstanding, without damage, a load of 300 pounds applied parallel to the run of the belt.
No handhold shall be provided without a corresponding step. If a handhold is removed permanently or temporarily, the corresponding step and handhold for the opposite direction of travel shall also be removed before the lift is again placed in service.
All handholds shall be of the closed type.
Two separate automatic stop devices shall be provided to cut off the power and apply the brake when a loaded step passes the upper terminal landing. One of these shall consist of a split-rail switch mechanically operated by the step roller and located not more than 6 inches above the top terminal landing. The second automatic stop device may consist of any of the following:
After the manlift has been stopped by a stop device it shall be necessary to reset the automatic stop manually. The device shall be so located that a person resetting it shall have a clear view of both the “up” and “down” runs of the manlift. It shall not be possible to reset the device from any step or platform.
The initial limit stop device shall function so that the manlift will be stopped before the loaded step has reached a point 24 inches above the top terminal landing.
An emergency stop means shall be provided.
This stop means shall be within easy reach of the ascending and descending runs of the belt.
This stop means shall be so connected with the control lever or operating mechanism that it will cut off the power and apply the brake when pulled in the direction of travel.
If rope is used, it shall be not less than three-eights inch in diameter. Wire rope, unless marlin-covered, shall not be used.
Signs of conspicuous and easily read style giving instructions for the use of the manlift shall be posted at each landing or stenciled on the belt.
Face the Belt.
Use the Handholds.
To Stop—Pull Rope.
“TOP FLOOR—GET OFF”
Signs shall be in block letters not less than 2 inches in height. This sign shall be located within easy view of an ascending passenger and not more than 2 feet above the top terminal landing.
A conspicuous sign having the following legend—AUTHORIZED PERSONNEL ONLY—shall be displayed at each landing.
No freight, packaged goods, pipe, lumber, or construction materials of any kind shall be handled on any manlift.
All manlifts shall be inspected by a competent designated person at intervals of not more than 30 days. Limit switches shall be checked weekly. Manlifts found to be unsafe shall not be operated until properly repaired.
This periodic inspection shall cover but is not limited to the following items:
Steps.
Step Fastenings.
Rails.
Rail Supports and Fastenings.
Rollers and Slides.
Belt and Belt Tension.
Handholds and Fastenings.
Floor Landings.
Guardrails.
Lubrication.
Limit Switches.
Warning Signs and Lights.
Illumination.
Drive Pulley.
Bottom (boot) Pulley and Clearance.
Pulley Supports.
Motor.
Driving Mechanism.
Brake.
Electrical Switches.
Vibration and Misalignment.
“Skip” on up or down run when mounting step (indicating worn gears).
A certification record shall be kept of each inspection which includes the date of the inspection, the signature of the person who performed the inspection and the serial number, or other identifier, of the manlift which was inspected. This record of inspection shall be made available to the Assistant Secretary of Labor or a duly authorized representative.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49746, Oct. 24, 1978; 51 FR 34560, Sept. 29, 1986; 54 FR 24334, June 7, 1989; 55 FR 32014, Aug. 6, 1990; 61 FR 9235, Mar. 7, 1996; 72 FR 71068, Dec. 14, 2007; 81 FR 82999, Nov. 18, 2016]
A solid substance used in an abrasive blasting operation.
A respirator constructed so that it covers the wearer's head, neck, and shoulders to protect the wearer from rebounding abrasive.
A complete enclosure which rotates on an axis, or which has an internal moving tread to tumble the parts, in order to expose various surfaces of the parts to the action of an automatic blast spray.
A complete enclosure in which blasting operations are performed and where the operator works inside of the room to operate the blasting nozzle and direct the flow of the abrasive material.
An enclosure where the operator stands outside and operates the blasting nozzle through an opening or openings in the enclosure.
Air of such purity that it will not cause harm or discomfort to an individual if it is inhaled for extended periods of time.
A device or combination of devices for separating dust from the air handled by an exhaust ventilation system.
A system for removing contaminated air from a space, comprising two or more of the following elements ( a ) enclosure or hood, ( b ) duct work, ( c ) dust collecting equipment, ( d ) exhauster, and ( e ) discharge stack.
An air purifying respirator, commonly referred to as a dust or a fume respirator, which removes most of the dust or fume from the air passing through the device.
Airborne dust in sizes capable of passing through the upper respiratory system to reach the lower lung passages.
An enclosure where the pieces to be cleaned are positioned on a rotating table and are passed automatically through a series of blast sprays.
The forcible application of an abrasive to a surface by pneumatic pressure, hydraulic pressure, or centrifugal force.
Air for abrasive-blasting respirators must be free of harmful quantities of dusts, mists, or noxious gases, and must meet the requirements for supplied-air quality and use specified in 29 CFR 1910.134(i).
Dust shall not be permitted to accumulate on the floor or on ledges outside of an abrasive-blasting enclosure, and dust spills shall be cleaned up promptly. Aisles and walkways shall be kept clear of steel shot or similar abrasive which may create a slipping hazard.
This paragraph (a) applies to all operations where an abrasive is forcibly applied to a surface by pneumatic or hydraulic pressure, or by centrifugal force. It does not apply to steam blasting, or steam cleaning, or hydraulic cleaning methods where work is done without the aid of abrasives.
Organic-bonded wheels, the thickness of which is not more than one forty-eighth of their diameter for those up to, and including, 20 inches in diameter, and not more than one-sixtieth of their diameter for those larger than 20 inches in diameter, used for a multitude of operations variously known as cutting, cutting off, grooving, slotting, coping, and jointing, and the like. The wheels may be “solid” consisting of organic-bonded abrasive material throughout, “steel centered” consisting of a steel disc with a rim of organic-bonded material moulded around the periphery, or of the “inserted tooth” type consisting of a steel disc with organic-bonded abrasive teeth or inserts mechanically secured around the periphery.
All power-driven, flexible, coated bands used for grinding, polishing, or buffing purposes.
The part of an exhaust system piping that is connected directly to the hood or enclosure.
A movable fixture, upon which the part to be ground or polished is placed.
All power-driven rotatable discs faced with abrasive materials, artificial or natural, and used for grinding or polishing on the side of the assembled disc.
The loss in static pressure caused by air flowing into a duct or hood. It is usually expressed in inches of water gauge.
A system consisting of branch pipes connected to hoods or enclosures, one or more header pipes, an exhaust fan, means for separating solid contaminants from the air flowing in the system, and a discharge stack to outside.
All power-driven rotatable grinding or abrasive wheels, except disc wheels as defined in this standard, consisting of abrasive particles held together by artificial or natural bonds and used for peripheral grinding.
A pipe into which one or more branch pipes enter and which connects such branch pipes to the remainder of the exhaust system.
The partial or complete enclosure around the wheel or disc through which air enters an exhaust system during operation.
A grinding machine carrying two power-driven, rotatable, coaxial, horizontal spindles upon the inside ends of which are mounted abrasive disc wheels used for grinding two surfaces simultaneously.
A grinding machine carrying an abrasive disc wheel upon one or both ends of a power-driven, rotatable single horizontal spindle.
All power-driven rotatable wheels composed all or in part of textile fabrics, wood, felt, leather, paper, and may be coated with abrasives on the periphery of the wheel for purposes of polishing, buffing, and light grinding.
Any power-driven rotatable grinding, polishing, or buffing wheel mounted in such manner that it may be manually manipulated.
All power-driven rotatable wheels made from wire or bristles, and used for scratch cleaning and brushing purposes.
Any power-driven rotatable grinding, polishing, or buffing wheel mounted in such a manner that the wheel with its supporting framework can be manipulated over stationary objects.
The kinetic pressure in the direction of flow necessary to cause a fluid at rest to flow at a given velocity. It is usually expressed in inches of water gauge.
A grinding machine having a vertical, rotatable power-driven spindle carrying a horizontal abrasive disc wheel.
Wherever dry grinding, dry polishing or buffing is performed, and employee exposure, without regard to the use of respirators, exceeds the permissible exposure limits prescribed in § 1910.1000 or other sections of this part, a local exhaust ventilation system shall be provided and used to maintain employee exposures within the prescribed limits.
| Wheel diameter (inches) | Wheel width (inches) | Minimum exhaust volume (feet 3 /min.) |
|---|---|---|
| To 9 | 1 1 ⁄ 2 | 220 |
| Over 9 to 16 | 2 | 390 |
| Over 16 to 19 | 3 | 500 |
| Over 19 to 24 | 4 | 610 |
| Over 24 to 30 | 5 | 880 |
| Over 30 to 36 | 6 | 1,200 |
For any wheel wider than wheel diameters shown in Table G-4, increase the exhaust volume by the ratio of the new width to the width shown.
Example:
1/2
4.5 ÷ 4 × 610 = 686 (rounded to 690).
| Wheel diameter (inches) | Wheel width (inches) | Minimum exhaust volume (feet 3 /min.) |
|---|---|---|
| To 9 | 2 | 300 |
| Over 9 to 16 | 3 | 500 |
| Over 16 to 19 | 4 | 610 |
| Over 19 to 24 | 5 | 740 |
| Over 24 to 30 | 6 | 1,040 |
| Over 30 to 36 | 6 | 1,200 |
| Disc diameter (inches) | Exhaust volume (ft. 3 /min.) |
|---|---|
| Up to 12 | 220 |
| Over 12 to 19 | 390 |
| Over 19 to 30 | 610 |
| Over 30 to 36 | 880 |
| Disc diameter (inches) | Exhaust volume (ft. 3 /min.) |
|---|---|
| Up to 19 | 610 |
| Over 19 to 25 | 880 |
| Over 25 to 30 | 1,200 |
| Over 30 to 53 | 1,770 |
| Over 53 to 72 | 6,280 |
| Disc diameter (inches) | One-half or more of disc covered | Disc not covered | ||
|---|---|---|---|---|
| Number 1 | Exhaust foot 3 /min.) | Number 1 | Exhaust foot 3 /min. | |
| Up to 20 | 1 | 500 | 2 | 780 |
| Over 20 to 30 | 2 | 780 | 2 | 1,480 |
| Over 30 to 53 | 2 | 1,770 | 4 | 3,530 |
| Over 53 to 72 | 2 | 3,140 | 5 | 6,010 |
| 1 Number of exhaust outlets around periphery of hood, or equal distribution provided by other means. |
| Belts width (inches) | Exhaust volume (ft. 3 /min.) |
|---|---|
| Up to 3 | 220 |
| Over 3 to 5 | 300 |
| Over 5 to 7 | 390 |
| Over 7 to 9 | 500 |
| Over 9 to 11 | 610 |
| Over 11 to 13 | 740 |
Where cradles are used for handling the parts to be ground, polished, or buffed, requiring large partial enclosures to house the complete operation, a minimum average air velocity of 150 feet per minute shall be maintained over the entire opening of the enclosure. Swing-frame grinders shall also be exhausted in the same manner as provided for cradles. (See fig. G-3)
| Dia D. inches | Exhaust E | Volume Exhausted at 4,500 ft/min ft 3 /min | Note | |
|---|---|---|---|---|
| Min. | Max. | No Pipes | Dia. | |
| 20 | 1 | 4 1 ⁄ 4 | 500 | When one-half or more of the disc can be hooded, use exhaust ducts as shown at the left. |
| Over 20 | 30 | 2 | 4 | 780 |
| Over 30 | 72 | 2 | 6 | 1,770 |
| Over 53 | 72 | 2 | 8 | 3,140 |
| 20 | 2 | 4 | 780 | When no hood can be used over disc, use exhaust ducts as shown at left. |
| Over 20 | 20 | 2 | 4 | 780 |
| Over 30 | 30 | 2 | 5 1 ⁄ 2 | 1,480 |
| Over 53 | 53 | 4 | 6 | 3,530 |
| 72 | 5 | 7 | 6,010 | |
| Entry loss = 1.0 slot velocity pressure + 0.5 branch velocity pressure. | ||||
| Minimum slot velocity = 2,000 ft/min— 1 ⁄ 2 -inch slot width. |
| Wheel dimension, inches | Exhaust outlet, inches E | Volume of air at 4,500 ft/min | ||
|---|---|---|---|---|
| Diameter | Width, Max | |||
| Min= d | Max= D | |||
| 9 | 1 1 ⁄ 2 | 3 | 220 | |
| Over 9 | 16 | 2 | 4 | 390 |
| Over 16 | 19 | 3 | 4 1 ⁄ 2 | 500 |
| Over 19 | 24 | 4 | 5 | 610 |
| Over 24 | 30 | 5 | 6 | 880 |
| Over 30 | 36 | 6 | 7 | 1,200 |
| Entry loss = 0.45 velocity pressure for tapered takeoff 0.65 velocity pressure for straight takeoff. |
| Wheel dimension, inches | Exhaust outlet, inches E | Volume of air at 4,500 ft/min | ||
|---|---|---|---|---|
| Diameter | Width, Max | |||
| Min= d | Max= D | |||
| 9 | 2 | 3 1 ⁄ 2 | 300 | |
| Over 9 | 16 | 3 | 4 | 500 |
| Over 16 | 19 | 4 | 5 | 610 |
| Over 19 | 24 | 5 | 5 1 ⁄ 2 | 740 |
| Over 24 | 30 | 6 | 6 1 ⁄ 2 | 1.040 |
| Over 30 | 36 | 6 | 7 | 1.200 |
| Entry loss = 0.15 velocity pressure for tapered takeoff; 0.65 velocity pressure for straight takeoff. |
| Dia D, inches | Exhaust E, dia. inches | Volume exhausted at 4,500 ft/min ft 3 /min | |
|---|---|---|---|
| Min. | Max. | ||
| 12 | 3 | 220 | |
| Over 12 | 19 | 4 | 390 |
| Over 19 | 30 | 5 | 610 |
| Over 30 | 36 | 6 | 880 |
| Note: If grinding wheels are used for disc grinding purposes, hoods must conform to structural strength and materials as described in 9.1. | |||
| Entry loss = 0.45 velocity pressure for tapered takeoff. |
| Disc dia. inches | Exhaust E | Volume exhaust at 4,500 ft/min. ft 3 /min | Note | ||
|---|---|---|---|---|---|
| Min. | Max. | No Pipes | Dia. | ||
| 19 | 1 | 5 | 610 | ||
| Over 19 | 25 | 1 | 6 | 880 | When width “W” permits, exhaust ducts should be as near heaviest grinding as possible. |
| Over 25 | 30 | 1 | 7 | 1,200 | |
| Over 30 | 53 | 2 | 6 | 1,770 | |
| Over 53 | 72 | 4 | 8 | 6,280 | |
| Entry loss = 0.45 velocity pressure for tapered takeoff. |
| Belt width W. Inches | Exhaust volume. ft. 1 /min |
|---|---|
| Up to 3 | 220 |
| 3 to 5 | 300 |
| 5 to 7 | 390 |
| 7 to 9 | 500 |
| 9 to 11 | 610 |
| 11 to 13 | 740 |
| Minimum duct velocity = 4,500 ft/min branch, 3,500 ft/min main. | |
| Entry loss = 0.45 velocity pressure for tapered takeoff; 0.65 velocity pressure for straight takeoff. |
This paragraph (b), prescribes the use of exhaust hood enclosures and systems in removing dust, dirt, fumes, and gases generated through the grinding, polishing, or buffing of ferrous and nonferrous metals.
Spray-finishing operations are employment of methods wherein organic or inorganic materials are utilized in dispersed form for deposit on surfaces to be coated, treated, or cleaned. Such methods of deposit may involve either automatic, manual, or electrostatic deposition but do not include metal spraying or metallizing, dipping, flow coating, roller coating, tumbling, centrifuging, or spray washing and degreasing as conducted in self-contained washing and degreasing machines or systems.
Spray booths are defined and described in § 1910.107(a).
A spray room is a room in which spray-finishing operations not conducted in a spray booth are performed separately from other areas.
Minimum maintained velocity is the velocity of air movement which must be maintained in order to meet minimum specified requirements for health and safety.
Spray booths or spray rooms are to be used to enclose or confine all operations. Spray-finishing operations shall be located as provided in sections 201 through 206 of the Standard for Spray Finishing Using Flammable and Combustible Materials, NFPA No. 33-1969.
| Operating conditions for objects completely inside booth | Crossdraft, f.p.m. | Airflow velocities, f.p.m. | |
|---|---|---|---|
| Design | Range | ||
| Electrostatic and automatic airless operation contained in booth without operator | Negligible | 50 large booth | 50-75 |
| 100 small booth | 75-125 | ||
| Air-operated guns, manual or automatic | Up to 50 | 100 large booth | 75-125 |
| 150 small booth | 125-175 | ||
| Air-operated guns, manual or automatic | Up to 100 | 150 large booth | 125-175 |
| 200 small booth | 150-250 | ||
| Notes: | |||
| (1) Attention is invited to the fact that the effectiveness of the spray booth is dependent upon the relationship of the depth of the booth to its height and width. | |||
| (2) Crossdrafts can be eliminated through proper design and such design should be sought. Crossdrafts in excess of 100fpm (feet per minute) should not be permitted. | |||
| (3) Excessive air pressures result in loss of both efficiency and material waste in addition to creating a backlash that may carry overspray and fumes into adjacent work areas. | |||
| (4) Booths should be designed with velocities shown in the column headed “Design.” However, booths operating with velocities shown in the column headed “Range” are in compliance with this standard. |
Example:
To determine the lower explosive limits of the most common solvents used in spray finishing, see Table G-11. Column 1 gives the number of cubic feet of vapor per gallon of solvent and column 2 gives the lower explosive limit (LEL) in percentage by volume of air. Note that the quantity of solvent will be diminished by the quantity of solids and nonflammables contained in the finish.
To determine the volume of air in cubic feet necessary to dilute the vapor from 1 gallon of solvent to 25 percent of the lower explosive limit, apply the following formula:
Dilution volume required per gallon of solvent = 4 (100−LEL) (cubic feet of vapor per gallon) ÷ LEL
Using toluene as the solvent.
of toluene from Table G-11, column 2, is 1.4 percent.
4 (100−1.4) 30.4 ÷ 1.4 = 8,564 cubic feet.
| Solvent | Cubic feet per gallon of vapor of liquid at 70 °F. | Lower explosive limit in percent by volume of air at 70 °F |
|---|---|---|
| Column 1 | Column 2 | |
| Acetone | 44.0 | 2.6 |
| Amyl Acetate (iso) | 21.6 | 1 1.0 |
| Amyl Alcohol (n) | 29.6 | 1.2 |
| Amyl Alcohol (iso) | 29.6 | 1.2 |
| Benzene | 36.8 | 1 1.4 |
| Butyl Acetate (n) | 24.8 | 1.7 |
| Butyl Alcohol (n) | 35.2 | 1.4 |
| Butyl Cellosolve | 24.8 | 1.1 |
| Cellosolve | 33.6 | 1.8 |
| Cellosolve Acetate | 23.2 | 1.7 |
| Cyclohexanone | 31.2 | 1 1.1 |
| 1,1 Dichloroethylene | 42.4 | 5.9 |
| 1,2 Dichloroethylene | 42.4 | 9.7 |
| Ethyl Acetate | 32.8 | 2.5 |
| Ethyl Alcohol | 55.2 | 4.3 |
| Ethyl Lactate | 28.0 | 1 1.5 |
| Methyl Acetate | 40.0 | 3.1 |
| Methyl Alcohol | 80.8 | 7.3 |
| Methyl Cellosolve | 40.8 | 2.5 |
| Methyl Ethyl Ketone | 36.0 | 1.8 |
| Methyl n-Propyl Ketone | 30.4 | 1.5 |
| Naphtha (VM&P) (76° Naphtha) | 22.4 | 0.9 |
| Naphtha (100 °Flash) Safety Solvent—Stoddard Solvent | 23.2 | 1.0 |
| Propyl Acetate (n) | 27.2 | 2.8 |
| Propyl Acetate (iso) | 28.0 | 1.1 |
| Propyl Alcohol (n) | 44.8 | 2.1 |
| Propyl Alcohol (iso) | 44.0 | 2.0 |
| Toluene | 30.4 | 1.4 |
| Turpentine | 20.8 | 0.8 |
| Xylene (o) | 26.4 | 1.0 |
| 1 At 212 °F. |
Spray booths or spray rooms are to be used to enclose or confine all spray finishing operations covered by this paragraph (c). This paragraph does not apply to the spraying of the exteriors of buildings, fixed tanks, or similar structures, nor to small portable spraying apparatus not used repeatedly in the same location.
[39 FR 23502, June 27, 1974, as amended at 40 FR 23073, May 28, 1975; 40 FR 24522, June 9, 1975; 43 FR 49746, Oct. 24, 1978; 49 FR 5322, Feb. 10, 1984; 55 FR 32015, Aug. 6, 1990; 58 FR 35308, June 30, 1993; 61 FR 9236, Mar. 7, 1996; 63 FR 1269, Jan. 8, 1998; 64 FR 13909, Mar. 23, 1999; 72 FR 71069, Dec. 14, 2007; 74 FR 46356, Sept. 9, 2009]
Equivalent sound level contours. Octave band sound pressure levels may be converted to the equivalent A-weighted sound level by plotting them on this graph and noting the A-weighted sound level corresponding to the point of highest penetration into the sound level contours. This equivalent A-weighted sound level, which may differ from the actual A-weighted sound level of the noise, is used to determine exposure limits from Table 1.G-16.
| Duration per day, hours | Sound level dBA slow response |
|---|---|
| 8 | 90 |
| 6 | 92 |
| 4 | 95 |
| 3 | 97 |
| 2 | 100 |
| 1 1 ⁄ 2 | 102 |
| 1 | 105 |
| 1 ⁄ 2 | 110 |
| 1 ⁄ 4 or less | 115 |
| 1 When the daily noise exposure is composed of two or more periods of noise exposure of different levels, their combined effect should be considered, rather than the individual effect of each. If the sum of the following fractions: C 1 / T 1 + C 2 / T 2 C n / T n exceeds unity, then, the mixed exposure should be considered to exceed the limit value. Cn indicates the total time of exposure at a specified noise level, and Tn indicates the total time of exposure permitted at that level. | |
| Exposure to impulsive or impact noise should not exceed 140 dB peak sound pressure level. |
The employer shall notify each employee exposed at or above an 8-hour time-weighted average of 85 decibels of the results of the monitoring.
The employer shall provide affected employees or their representatives with an opportunity to observe any noise measurements conducted pursuant to this section.
Where mobile test vans are used to meet the audiometric testing obligation, the employer shall obtain a valid baseline audiogram within 1 year of an employee's first exposure at or above the action level. Where baseline audiograms are obtained more than 6 months after the employee's first exposure at or above the action level, employees shall wearing hearing protectors for any period exceeding six months after first exposure until the baseline audiogram is obtained.
At least annually after obtaining the baseline audiogram, the employer shall obtain a new audiogram for each employee exposed at or above an 8-hour time-weighted average of 85 decibels.
An annual audiogram may be substituted for the baseline audiogram when, in the judgment of the audiologist, otolaryngologist or physician who is evaluating the audiogram:
The employer shall maintain an accurate record of all employee exposure measurements required by paragraph (d) of this section.
The employer shall retain records required in this paragraph (m) for at least the following periods.
All records required by this section shall be provided upon request to employees, former employees, representatives designated by the individual employee, and the Assistant Secretary. The provisions of 29 CFR 1910.1020 (a)-
If the employer ceases to do business, the employer shall transfer to the successor employer all records required to be maintained by this section, and the successor employer shall retain them for the remainder of the period prescribed in paragraph (m)(3) of this section.
Paragraphs (c) through (n) of this section shall not apply to employers engaged in oil and gas well drilling and servicing operations.
Appendix A to § 1910.95—Noise Exposure Computation
This appendix is Mandatory
I. Computation of Employee Noise Exposure
1
1
2
2
n
n
where C n indicates the total time of exposure at a specific noise level, and T n indicates the reference duration for that level as given by Table G-16a.
| A-weighted sound level, L (decibel) | Reference duration, T (hour) |
|---|---|
| 80 | 32 |
| 81 | 27.9 |
| 82 | 24.3 |
| 83 | 21.1 |
| 84 | 18.4 |
| 85 | 16 |
| 86 | 13.9 |
| 87 | 12.1 |
| 88 | 10.6 |
| 89 | 9.2 |
| 90 | 8 |
| 91 | 7.0 |
| 92 | 6.1 |
| 93 | 5.3 |
| 94 | 4.6 |
| 95 | 4 |
| 96 | 3.5 |
| 97 | 3.0 |
| 98 | 2.6 |
| 99 | 2.3 |
| 100 | 2 |
| 101 | 1.7 |
| 102 | 1.5 |
| 103 | 1.3 |
| 104 | 1.1 |
| 105 | 1 |
| 106 | 0.87 |
| 107 | 0.76 |
| 108 | 0.66 |
| 109 | 0.57 |
| 110 | 0.5 |
| 111 | 0.44 |
| 112 | 0.38 |
| 113 | 0.33 |
| 114 | 0.29 |
| 115 | 0.25 |
| 116 | 0.22 |
| 117 | 0.19 |
| 118 | 0.16 |
| 119 | 0.14 |
| 120 | 0.125 |
| 121 | 0.11 |
| 122 | 0.095 |
| 123 | 0.082 |
| 124 | 0.072 |
| 125 | 0.063 |
| 126 | 0.054 |
| 127 | 0.047 |
| 128 | 0.041 |
| 129 | 0.036 |
| 130 | 0.031 |
In the above table the reference duration, T, is computed by
where L is the measured A-weighted sound level.
II. Conversion Between “Dose” and “8-Hour Time-Weighted Average” Sound Level
Compliance with paragraphs (c)-
In order to convert the reading of a dosimeter into TWA, see Table A-1, below. This table applies to dosimeters that are set by the manufacturer to calculate dose or percent exposure according to the relationships in Table G-16a. So, for example, a dose of 91 percent over an eight hour day results in a TWA of 89.3 dB, and, a dose of 50 percent corresponds to a TWA of 85 dB.
If the dose as read on the dosimeter is less than or greater than the values found in Table A-1, the TWA may be calculated by using the formula: TWA=16.61 log 10 (D/100) + 90 where TWA = 8-hour time-weighted average sound level and D = accumulated dose in percent exposure.
| Dose or percent noise exposure | TWA |
|---|---|
| 10 | 73.4 |
| 15 | 76.3 |
| 20 | 78.4 |
| 25 | 80.0 |
| 30 | 81.3 |
| 35 | 82.4 |
| 40 | 83.4 |
| 45 | 84.2 |
| 50 | 85.0 |
| 55 | 85.7 |
| 60 | 86.3 |
| 65 | 86.9 |
| 70 | 87.4 |
| 75 | 87.9 |
| 80 | 88.4 |
| 81 | 88.5 |
| 82 | 88.6 |
| 83 | 88.7 |
| 84 | 88.7 |
| 85 | 88.8 |
| 86 | 88.9 |
| 87 | 89.0 |
| 88 | 89.1 |
| 89 | 89.2 |
| 90 | 89.2 |
| 91 | 89.3 |
| 92 | 89.4 |
| 93 | 89.5 |
| 94 | 89.6 |
| 95 | 89.6 |
| 96 | 89.7 |
| 97 | 89.8 |
| 98 | 89.9 |
| 99 | 89.9 |
| 100 | 90.0 |
| 101 | 90.1 |
| 102 | 90.1 |
| 103 | 90.2 |
| 104 | 90.3 |
| 105 | 90.4 |
| 106 | 90.4 |
| 107 | 90.5 |
| 108 | 90.6 |
| 109 | 90.6 |
| 110 | 90.7 |
| 111 | 90.8 |
| 112 | 90.8 |
| 113 | 90.9 |
| 114 | 90.9 |
| 115 | 91.1 |
| 116 | 91.1 |
| 117 | 91.1 |
| 118 | 91.2 |
| 119 | 91.3 |
| 120 | 91.3 |
| 125 | 91.6 |
| 130 | 91.9 |
| 135 | 92.2 |
| 140 | 92.4 |
| 145 | 92.7 |
| 150 | 92.9 |
| 155 | 93.2 |
| 160 | 93.4 |
| 165 | 93.6 |
| 170 | 93.8 |
| 175 | 94.0 |
| 180 | 94.2 |
| 185 | 94.4 |
| 190 | 94.6 |
| 195 | 94.8 |
| 200 | 95.0 |
| 210 | 95.4 |
| 220 | 95.7 |
| 230 | 96.0 |
| 240 | 96.3 |
| 250 | 96.6 |
| 260 | 96.9 |
| 270 | 97.2 |
| 280 | 97.4 |
| 290 | 97.7 |
| 300 | 97.9 |
| 310 | 98.2 |
| 320 | 98.4 |
| 330 | 98.6 |
| 340 | 98.8 |
| 350 | 99.0 |
| 360 | 99.2 |
| 370 | 99.4 |
| 380 | 99.6 |
| 390 | 99.8 |
| 400 | 100.0 |
| 410 | 100.2 |
| 420 | 100.4 |
| 430 | 100.5 |
| 440 | 100.7 |
| 450 | 100.8 |
| 460 | 101.0 |
| 470 | 101.2 |
| 480 | 101.3 |
| 490 | 101.5 |
| 500 | 101.6 |
| 510 | 101.8 |
| 520 | 101.9 |
| 530 | 102.0 |
| 540 | 102.2 |
| 550 | 102.3 |
| 560 | 102.4 |
| 570 | 102.6 |
| 580 | 102.7 |
| 590 | 102.8 |
| 600 | 102.9 |
| 610 | 103.0 |
| 620 | 103.2 |
| 630 | 103.3 |
| 640 | 103.4 |
| 650 | 103.5 |
| 660 | 103.6 |
| 670 | 103.7 |
| 680 | 103.8 |
| 690 | 103.9 |
| 700 | 104.0 |
| 710 | 104.1 |
| 720 | 104.2 |
| 730 | 104.3 |
| 740 | 104.4 |
| 750 | 104.5 |
| 760 | 104.6 |
| 770 | 104.7 |
| 780 | 104.8 |
| 790 | 104.9 |
| 800 | 105.0 |
| 810 | 105.1 |
| 820 | 105.2 |
| 830 | 105.3 |
| 840 | 105.4 |
| 850 | 105.4 |
| 860 | 105.5 |
| 870 | 105.6 |
| 880 | 105.7 |
| 890 | 105.8 |
| 900 | 105.8 |
| 910 | 105.9 |
| 920 | 106.0 |
| 930 | 106.1 |
| 940 | 106.2 |
| 950 | 106.2 |
| 960 | 106.3 |
| 970 | 106.4 |
| 980 | 106.5 |
| 990 | 106.5 |
| 999 | 106.6 |
Appendix B to § 1910.95—Methods for Estimating the Adequacy of Hearing Protector Attenuation
This appendix is Mandatory
For employees who have experienced a significant threshold shift, hearing protector attenuation must be sufficient to reduce employee exposure to a TWA of 85 dB. Employers must select one of the following methods by which to estimate the adequacy of hearing protector attenuation.
The most convenient method is the Noise Reduction Rating (NRR) developed by the Environmental Protection Agency (EPA). According to EPA regulation, the NRR must be shown on the hearing protector package. The NRR is then related to an individual worker's noise environment in order to assess the adequacy of the attenuation of a given hearing protector. This appendix describes four methods of using the NRR to determine whether a particular hearing protector provides adequate protection within a given exposure environment. Selection among the four procedures is dependent upon the employer's noise measuring instruments.
Instead of using the NRR, employers may evaluate the adequacy of hearing protector attenuation by using one of the three methods developed by the National Institute for Occupational Safety and Health (NIOSH), which are described in the “List of Personal Hearing Protectors and Attenuation Data,” HEW Publication No. 76-120, 1975, pages 21-37. These methods are known as NIOSH methods #1B1, #1B2 and #1B3. The NRR described below is a simplification of NIOSH method #1B2. The most complex method is NIOSH method #1B1, which is probably the most accurate method since it uses the largest amount of spectral information from the individual employee's noise environment. As in the case of the NRR method described below, if one of the NIOSH methods is used, the selected method must be applied to an individual's noise environment to assess the adequacy of the attenuation. Employers should be careful to take a sufficient number of measurements in order to achieve a representative sample for each time segment.
When using the NRR to assess hearing protector adequacy, one of the following methods must be used:
Appendix C to § 1910.95—Audiometric Measuring Instruments
This appendix is Mandatory
1. In the event that pulsed-tone audiometers are used, they shall have a tone on-time of at least 200 milliseconds.
2. Self-recording audiometers shall comply with the following requirements:
Appendix D to § 1910.95—Audiometric Test Rooms
This appendix is Mandatory
Rooms used for audiometric testing shall not have background sound pressure levels exceeding those in Table D-1 when measured by equipment conforming at least to the Type 2 requirements of American National Standard Specification for Sound Level Meters, S1.4-1971 (R1976), and to the Class II requirements of American National Standard Specification for Octave, Half-Octave, and Third-Octave Band Filter Sets, S1.11-1971 (R1976).
| Octave-band center frequency (Hz) | 500 | 1000 | 2000 | 4000 | 8000 |
|---|---|---|---|---|---|
| Sound pressure level (dB) | 40 | 40 | 47 | 57 | 62 |
Appendix E to § 1910.95—Acoustic Calibration of Audiometers
This appendix is Mandatory
Audiometer calibration shall be checked acoustically, at least annually, according to the procedures described in this appendix. The equipment necessary to perform these measurements is a sound level meter, octave-band filter set, and a National Bureau of Standards 9A coupler. In making these measurements, the accuracy of the calibrating equipment shall be sufficient to determine that the audiometer is within the tolerances permitted by American Standard Specification for Audiometers, S3.6-1969.
A. Place the earphone coupler over the microphone of the sound level meter and place the earphone on the coupler.
B. Set the audiometer's hearing threshold level (HTL) dial to 70 dB.
C. Measure the sound pressure level of the tones at each test frequency from 500 Hz through 6000 Hz for each earphone.
D. At each frequency the readout on the sound level meter should correspond to the levels in Table E-1 or Table E-2, as appropriate, for the type of earphone, in the column entitled “sound level meter reading.”
A. With the earphone in place, set the frequency to 1000 Hz and the HTL dial on the audiometer to 70 dB.
B. Measure the sound levels in the coupler at each 10-dB decrement from 70 dB to 10 dB, noting the sound level meter reading at each setting.
C. For each 10-dB decrement on the audiometer the sound level meter should indicate a corresponding 10 dB decrease.
D. This measurement may be made electrically with a voltmeter connected to the earphone terminals.
When any of the measured sound levels deviate from the levels in Table E-1 or Table E-2 by ±3 dB at any test frequency between 500 and 3000 Hz, 4 dB at 4000 Hz, or 5 dB at 6000 Hz, an exhaustive calibration is advised. An exhaustive calibration is required if the deviations are greater than 15 dB or greater at any test frequency.
| Frequency, Hz | Reference threshold level for TDH-39 earphones, dB | Sound level meter reading, dB |
|---|---|---|
| 500 | 11.5 | 81.5 |
| 1000 | 7 | 77 |
| 2000 | 9 | 79 |
| 3000 | 10 | 80 |
| 4000 | 9.5 | 79.5 |
| 6000 | 15.5 | 85.5 |
| Frequency, Hz | Reference threshold level for TDH-49 earphones, dB | Sound level meter reading, dB |
|---|---|---|
| 500 | 13.5 | 83.5 |
| 1000 | 7.5 | 77.5 |
| 2000 | 11 | 81.0 |
| 3000 | 9.5 | 79.5 |
| 4000 | 10.5 | 80.5 |
| 6000 | 13.5 | 83.5 |
Appendix F to § 1910.95—Calculations and Application of Age Corrections to Audiograms
This appendix Is Non-Mandatory
In determining whether a standard threshold shift has occurred, allowance may be made for the contribution of aging to the change in hearing level by adjusting the most recent audiogram. If the employer chooses to adjust the audiogram, the employer shall follow the procedure described below. This procedure and the age correction tables were developed by the National Institute for Occupational Safety and Health in the criteria document entitled “Criteria for a Recommended Standard... Occupational Exposure to Noise,” ((HSM)-11001).
For each audiometric test frequency;
Example:
Employee is a 32-year-old male. The audiometric history for his right ear is shown in decibels below.
| Employee's age | Audiometric test frequency (Hz) | ||||
|---|---|---|---|---|---|
| 1000 | 2000 | 3000 | 4000 | 6000 | |
| 26 | 10 | 5 | 5 | 10 | 5 |
| *27 | 0 | 0 | 0 | 5 | 5 |
| 28 | 0 | 0 | 0 | 10 | 5 |
| 29 | 5 | 0 | 5 | 15 | 5 |
| 30 | 0 | 5 | 10 | 20 | 10 |
| 31 | 5 | 10 | 20 | 15 | 15 |
| *32 | 5 | 10 | 10 | 25 | 20 |
The audiogram at age 27 is considered the baseline since it shows the best hearing threshold levels. Asterisks have been used to identify the baseline and most recent audiogram. A threshold shift of 20 dB exists at 4000 Hz between the audiograms taken at ages 27 and 32.
The contribution of aging to this change in hearing may be estimated in the following manner:
Go to Table F-1 and find the age correction values (in dB) for 4000 Hz at age 27 and age 32.
| Frequency (Hz) | |||||
|---|---|---|---|---|---|
| 1000 | 2000 | 3000 | 4000 | 6000 | |
| Age 32 | 6 | 5 | 7 | 10 | 14 |
| Age 27 | 5 | 4 | 6 | 7 | 11 |
| Difference | 1 | 1 | 1 | 3 | 3 |
The difference represents the amount of hearing loss that may be attributed to aging in the time period between the baseline audiogram and the most recent audiogram. In this example, the difference at 4000 Hz is 3 dB. This value is subtracted from the hearing level at 4000 Hz, which in the most recent audiogram is 25, yielding 22 after adjustment. Then the hearing threshold in the baseline audiogram at 4000 Hz (5) is subtracted from the adjusted annual audiogram hearing threshold at 4000 Hz (22). Thus the age-corrected threshold shift would be 17 dB (as opposed to a threshold shift of 20 dB without age correction).
| Years | Audiometric Test Frequencies (Hz) | ||||
|---|---|---|---|---|---|
| 1000 | 2000 | 3000 | 4000 | 6000 | |
| 20 or younger | 5 | 3 | 4 | 5 | 8 |
| 21 | 5 | 3 | 4 | 5 | 8 |
| 22 | 5 | 3 | 4 | 5 | 8 |
| 23 | 5 | 3 | 4 | 6 | 9 |
| 24 | 5 | 3 | 5 | 6 | 9 |
| 25 | 5 | 3 | 5 | 7 | 10 |
| 26 | 5 | 4 | 5 | 7 | 10 |
| 27 | 5 | 4 | 6 | 7 | 11 |
| 28 | 6 | 4 | 6 | 8 | 11 |
| 29 | 6 | 4 | 6 | 8 | 12 |
| 30 | 6 | 4 | 6 | 9 | 12 |
| 31 | 6 | 4 | 7 | 9 | 13 |
| 32 | 6 | 5 | 7 | 10 | 14 |
| 33 | 6 | 5 | 7 | 10 | 14 |
| 34 | 6 | 5 | 8 | 11 | 15 |
| 35 | 7 | 5 | 8 | 11 | 15 |
| 36 | 7 | 5 | 9 | 12 | 16 |
| 37 | 7 | 6 | 9 | 12 | 17 |
| 38 | 7 | 6 | 9 | 13 | 17 |
| 39 | 7 | 6 | 10 | 14 | 18 |
| 40 | 7 | 6 | 10 | 14 | 19 |
| 41 | 7 | 6 | 10 | 14 | 20 |
| 42 | 8 | 7 | 11 | 16 | 20 |
| 43 | 8 | 7 | 12 | 16 | 21 |
| 44 | 8 | 7 | 12 | 17 | 22 |
| 45 | 8 | 7 | 13 | 18 | 23 |
| 46 | 8 | 8 | 13 | 19 | 24 |
| 47 | 8 | 8 | 14 | 19 | 24 |
| 48 | 9 | 8 | 14 | 20 | 25 |
| 49 | 9 | 9 | 15 | 21 | 26 |
| 50 | 9 | 9 | 16 | 22 | 27 |
| 51 | 9 | 9 | 16 | 23 | 28 |
| 52 | 9 | 10 | 17 | 24 | 29 |
| 53 | 9 | 10 | 18 | 25 | 30 |
| 54 | 10 | 10 | 18 | 26 | 31 |
| 55 | 10 | 11 | 19 | 27 | 32 |
| 56 | 10 | 11 | 20 | 28 | 34 |
| 57 | 10 | 11 | 21 | 29 | 35 |
| 58 | 10 | 12 | 22 | 31 | 36 |
| 59 | 11 | 12 | 22 | 32 | 37 |
| 60 or older | 11 | 13 | 23 | 33 | 38 |
| Years | Audiometric Test Frequencies (Hz) | ||||
|---|---|---|---|---|---|
| 1000 | 2000 | 3000 | 4000 | 6000 | |
| 20 or younger | 7 | 4 | 3 | 3 | 6 |
| 21 | 7 | 4 | 4 | 3 | 6 |
| 22 | 7 | 4 | 4 | 4 | 6 |
| 23 | 7 | 5 | 4 | 4 | 7 |
| 24 | 7 | 5 | 4 | 4 | 7 |
| 25 | 8 | 5 | 4 | 4 | 7 |
| 26 | 8 | 5 | 5 | 4 | 8 |
| 27 | 8 | 5 | 5 | 5 | 8 |
| 28 | 8 | 5 | 5 | 5 | 8 |
| 29 | 8 | 5 | 5 | 5 | 9 |
| 30 | 8 | 6 | 5 | 5 | 9 |
| 31 | 8 | 6 | 6 | 5 | 9 |
| 32 | 9 | 6 | 6 | 6 | 10 |
| 33 | 9 | 6 | 6 | 6 | 10 |
| 34 | 9 | 6 | 6 | 6 | 10 |
| 35 | 9 | 6 | 7 | 7 | 11 |
| 36 | 9 | 7 | 7 | 7 | 11 |
| 37 | 9 | 7 | 7 | 7 | 12 |
| 38 | 10 | 7 | 7 | 7 | 12 |
| 39 | 10 | 7 | 8 | 8 | 12 |
| 40 | 10 | 7 | 8 | 8 | 13 |
| 41 | 10 | 8 | 8 | 8 | 13 |
| 42 | 10 | 8 | 9 | 9 | 13 |
| 43 | 11 | 8 | 9 | 9 | 14 |
| 44 | 11 | 8 | 9 | 9 | 14 |
| 45 | 11 | 8 | 10 | 10 | 15 |
| 46 | 11 | 9 | 10 | 10 | 15 |
| 47 | 11 | 9 | 10 | 11 | 16 |
| 48 | 12 | 9 | 11 | 11 | 16 |
| 49 | 12 | 9 | 11 | 11 | 16 |
| 50 | 12 | 10 | 11 | 12 | 17 |
| 51 | 12 | 10 | 12 | 12 | 17 |
| 52 | 12 | 10 | 12 | 13 | 18 |
| 53 | 13 | 10 | 13 | 13 | 18 |
| 54 | 13 | 11 | 13 | 14 | 19 |
| 55 | 13 | 11 | 14 | 14 | 19 |
| 56 | 13 | 11 | 14 | 15 | 20 |
| 57 | 13 | 11 | 15 | 15 | 20 |
| 58 | 14 | 12 | 15 | 16 | 21 |
| 59 | 14 | 12 | 16 | 16 | 21 |
| 60 or older | 14 | 12 | 16 | 17 | 22 |
Appendix G to § 1910.95—Monitoring Noise Levels Non-Mandatory Informational Appendix
This appendix provides information to help employers comply with the noise monitoring obligations that are part of the hearing conservation amendment.
What is the purpose of noise monitoring?
This revised amendment requires that employees be placed in a hearing conservation program if they are exposed to average noise levels of 85 dB or greater during an 8 hour workday. In order to determine if exposures are at or above this level, it may be necessary to measure or monitor the actual noise levels in the workplace and to estimate the noise exposure or “dose” received by employees during the workday.
When is it necessary to implement a noise monitoring program?
It is not necessary for every employer to measure workplace noise. Noise monitoring or measuring must be conducted only when exposures are at or above 85 dB. Factors which suggest that noise exposures in the workplace may be at this level include employee complaints about the loudness of noise, indications that employees are losing their hearing, or noisy conditions which make normal conversation difficult. The employer should also consider any information available regarding noise emitted from specific machines. In addition, actual workplace noise measurements can suggest whether or not a monitoring program should be initiated.
How is noise measured?
Basically, there are two different instruments to measure noise exposures: the sound level meter and the dosimeter. A sound level meter is a device that measures the intensity of sound at a given moment. Since sound level meters provide a measure of sound intensity at only one point in time, it is generally necessary to take a number of measurements at different times during the day to estimate noise exposure over a workday. If noise levels fluctuate, the amount of time noise remains at each of the various measured levels must be determined.
To estimate employee noise exposures with a sound level meter it is also generally necessary to take several measurements at different locations within the workplace. After appropriate sound level meter readings are obtained, people sometimes draw “maps” of the sound levels within different areas of the workplace. By using a sound level “map” and information on employee locations throughout the day, estimates of individual exposure levels can be developed. This measurement method is generally referred to as area noise monitoring.
A dosimeter is like a sound level meter except that it stores sound level measurements and integrates these measurements over time, providing an average noise exposure reading for a given period of time, such as an 8-hour workday. With a dosimeter, a microphone is attached to the employee's clothing and the exposure measurement is simply read at the end of the desired time period. A reader may be used to read-out the dosimeter's measurements. Since the dosimeter is worn by the employee, it measures noise levels in those locations in which the employee travels. A sound level meter can also be positioned within the immediate vicinity of the exposed worker to obtain an individual exposure estimate. Such procedures are generally referred to as personal noise monitoring.
Area monitoring can be used to estimate noise exposure when the noise levels are relatively constant and employees are not mobile. In workplaces where employees move about in different areas or where the noise intensity tends to fluctuate over time, noise exposure is generally more accurately estimated by the personal monitoring approach.
In situations where personal monitoring is appropriate, proper positioning of the microphone is necessary to obtain accurate measurements. With a dosimeter, the microphone is generally located on the shoulder and remains in that position for the entire workday. With a sound level meter, the microphone is stationed near the employee's head, and the instrument is usually held by an individual who follows the employee as he or she moves about.
Manufacturer's instructions, contained in dosimeter and sound level meter operating manuals, should be followed for calibration and maintenance. To ensure accurate results, it is considered good professional practice to calibrate instruments before and after each use.
How often is it necessary to monitor noise levels?
The amendment requires that when there are significant changes in machinery or production processes that may result in increased noise levels, remonitoring must be conducted to determine whether additional employees need to be included in the hearing conservation program. Many companies choose to remonitor periodically (once every year or two) to ensure that all exposed employees are included in their hearing conservation programs.
Where can equipment and technical advice be obtained?
Noise monitoring equipment may be either purchased or rented. Sound level meters cost about $500 to $1,000, while dosimeters range in price from about $750 to $1,500. Smaller companies may find it more economical to rent equipment rather than to purchase it. Names of equipment suppliers may be found in the telephone book (Yellow Pages) under headings such as: “Safety Equipment,” “Industrial Hygiene,” or “Engineers-Acoustical.” In addition to providing information on obtaining noise monitoring equipment, many companies and individuals included under such listings can provide professional advice on how to conduct a valid noise monitoring program. Some audiological testing firms and industrial hygiene firms also provide noise monitoring services. Universities with audiology, industrial hygiene, or acoustical engineering departments may also provide information or may be able to help employers meet their obligations under this amendment.
Free, on-site assistance may be obtained from OSHA-supported state and private consultation organizations. These safety and health consultative entities generally give priority to the needs of small businesses.
Appendix H to § 1910.95—Availability of Referenced Documents
Paragraphs (c) through (o) of 29 CFR 1910.95 and the accompanying appendices contain provisions which incorporate publications by reference. Generally, the publications provide criteria for instruments to be used in monitoring and audiometric testing. These criteria are intended to be mandatory when so indicated in the applicable paragraphs of § 1910.95 and appendices.
It should be noted that OSHA does not require that employers purchase a copy of the referenced publications. Employers, however, may desire to obtain a copy of the referenced publications for their own information.
The designation of the paragraph of the standard in which the referenced publications appear, the titles of the publications, and the availability of the publications are as follows:
| Paragraph designation | Referenced publication | Available from— |
|---|---|---|
| Appendix B | “List of Personal Hearing Protectors and Attenuation Data,” HEW Pub. No. 76-120, 1975. NTIS-PB267461 | National Technical Information Service, Port Royal Road, Springfield, VA 22161. |
| Appendix D | “Specification for Sound Level Meters,” S1.4-1971 (R1976) | American National Standards Institute, Inc., 1430 Broadway, New York, NY 10018. |
| § 1910.95(k)(2), appendix E | “Specifications for Audiometers,” S3.6-1969 | American National Standards Institute, Inc., 1430 Broadway, New York, NY 10018. |
| Appendix D | “Specification for Octave, Half-Octave and Third-Octave Band Filter Sets,” S1.11-1971 (R1976) | Back Numbers Department, Dept. STD, American Institute of Physics, 333 E. 45th St., New York, NY 10017; American National Standards Institute, Inc., 1430 Broadway, New York, NY 10018. |
The referenced publications (or a microfiche of the publications) are available for review at many universities and public libraries throughout the country. These publications may also be examined at the OSHA Technical Data Center, Room N2439, United States Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210, (202) 219-7500 or at any OSHA Regional Office (see telephone directories under United States Government—Labor Department).
Appendix I to § 1910.95—Definitions
These definitions apply to the following terms as used in paragraphs (c) through (n) of 29 CFR 1910.95.
Action level—An 8-hour time-weighted average of 85 decibels measured on the A-scale, slow response, or equivalently, a dose of fifty percent.
Audiogram—A chart, graph, or table resulting from an audiometric test showing an individual's hearing threshold levels as a function of frequency.
Audiologist—A professional, specializing in the study and rehabilitation of hearing, who is certified by the American Speech-Language-Hearing Association or licensed by a state board of examiners.
Baseline audiogram—The audiogram against which future audiograms are compared.
Criterion sound level—A sound level of 90 decibels.
Decibel (dB)—Unit of measurement of sound level.
Hertz (Hz)—Unit of measurement of frequency, numerically equal to cycles per second.
Medical pathology—A disorder or disease. For purposes of this regulation, a condition or disease affecting the ear, which should be treated by a physician specialist.
Noise dose—The ratio, expressed as a percentage, of (1) the time integral, over a stated time or event, of the 0.6 power of the measured SLOW exponential time-averaged, squared A-weighted sound pressure and (2) the product of the criterion duration (8 hours) and the 0.6 power of the squared sound pressure corresponding to the criterion sound level (90 dB).
Noise dosimeter—An instrument that integrates a function of sound pressure over a period of time in such a manner that it directly indicates a noise dose.
Otolaryngologist—A physician specializing in diagnosis and treatment of disorders of the ear, nose and throat.
Representative exposure—Measurements of an employee's noise dose or 8-hour time-weighted average sound level that the employers deem to be representative of the exposures of other employees in the workplace.
Sound level—Ten times the common logarithm of the ratio of the square of the measured A-weighted sound pressure to the square of the standard reference pressure of 20 micropascals. Unit: decibels (dB). For use with this regulation, SLOW time response, in accordance with ANSI S1.4-1971 (R1976), is required.
Sound level meter—An instrument for the measurement of sound level.
Time-weighted average sound level—That sound level, which if constant over an 8-hour exposure, would result in the same noise dose as is measured.
[39 FR 23502, June 27, 1974, as amended at 46 FR 4161, Jan. 16, 1981; 46 FR 62845, Dec. 29, 1981; 48 FR 9776, Mar. 8, 1983; 48 FR 29687, June 28, 1983; 54 FR 24333, June 7, 1989; 61 FR 9236, Mar. 7, 1996; 71 FR 16672, Apr. 3, 2006; 73 FR 75584, Dec. 12, 2008]
Pertains to the case in which part of the body is exposed to the incident electromagnetic energy.
Radiation level which should not be exceeded without careful consideration of the reasons for doing so.
Pertains to the case in which the entire body is exposed to the incident electromagnetic energy or in which the cross section of the body is smaller than the cross section of the incident radiation beam.
2
2
This guide applies whether the radiation is continuous or intermittent.
Z53.1-1967 or ANSI Z535.1-2006(R2011), incorporated by reference in § 1910.6, is for use for color specification. All lettering and the border shall be of aluminum color.
This section applies to all radiations originating from radio stations, radar equipment, and other possible sources of electromagnetic radiation such as used for communication, radio navigation, and industrial and scientific purposes. This section does not apply to the deliberate exposure of patients by, or under the direction of, practitioners of the healing arts.
[39 FR 23502, June 27, 1974, as amended at 61 FR 9236, Mar. 7, 1996; 78 FR 35566, June 13, 2013]
§ 1910.94 (a)(2)(iii), (a)(3), (a)(4), (b), (c)(2), (c)(3), (c)(4), (c)(5), (c)(6)(i), (c)(6)(ii), (d)(1)(ii), (d)(3), (d)(4), (d)(5), and (d)(7).
Each employer shall determine that compressed gas cylinders under his control are in a safe condition to the extent that this can be determined by visual inspection. Visual and other inspections shall be conducted as prescribed in the Hazardous Materials Regulations of the Department of Transportation (49 CFR parts 171-179 and 14 CFR part 103). Where those regulations are not applicable, visual and other inspections shall be conducted in accordance with Compressed Gas Association Pamphlets C-6-1968 and C-8-1962, which is incorporated by reference as specified in § 1910.6.
The in-plant handling, storage, and utilization of all compressed gases in cylinders, portable tanks, rail tankcars, or motor vehicle cargo tanks shall be in accordance with Compressed Gas Association Pamphlet P-1-1965, which is incorporated by reference as specified in § 1910.6.
Compressed gas cylinders, portable tanks, and cargo tanks shall have pressure relief devices installed and maintained in accordance with Compressed Gas Association Pamphlets S-1.1-1963 and 1965 addenda and S-1.2-1963, which is incorporated by reference as specified in § 1910.6.
[39 FR 23502, June 27, 1974, as amended at 61 FR 9236, Mar. 7, 1996]
Employers must ensure that the in-plant transfer, handling, storage, and use of acetylene in cylinders comply with the provisions of CGA Pamphlet G-1-2009 (“Acetylene”) (incorporated by reference, see § 1910.6).
[74 FR 40447, Aug. 11, 2009, as amended at 76 FR 75786, Dec. 5, 2011]
As used in this section
Specifications—Regulations of the Department of Transportation published in 49 CFR Chapter I.
regulations—See § 1910.103 (a)(1)(v).
The hydrogen storage location shall be permanently placarded as follows: “HYDROGEN—FLAMMABLE GAS—NO SMOKING—NO OPEN FLAMES,” or equivalent.
After installations, all piping, tubing, and fittings shall be tested and proved hydrogen gas tight at maximum operating pressure.
| Nature of location | Size of hydrogen system | ||
|---|---|---|---|
| Less than 3,000 CF | 3,000 CF to 15,000 CF | In excess of 15,000 CF | |
| Outdoors | I | IDI. | |
| In a separate building | II | II | II. |
| In a special room | III | III | Not permitted. |
| Inside buildings not in a special room and exposed to other occupancies | IV | Not permitted | Not permitted. |
| Type of outdoor exposure | Size of hydrogen system | |||
|---|---|---|---|---|
| Less than 3,000 CF | 3,000 CF to 15,000 CF | In excess of 15,000 CF | ||
| 1. Building or structure | Wood frame construction 1 | 10 | 25 | 50 |
| Heavy timber, noncombustible or ordinary construction 1 | 0 | 10 | 2 25 | |
| Fire-resistive construction 1 | 0 | 0 | 0 | |
| 2. Wall openings | Not above any part of a system | 10 | 10 | 10 |
| Above any part of a system | 25 | 25 | 25 | |
| 3. Flammable liquids above ground. | 0 to 1,000 gallons In excess of 1,000 gallons | 10 25 | 25 50 | 25 50 |
| 4. Flammable liquids below ground—0 to 1,000 gallons | Tank Vent or fill opening of tank | 10 25 | 10 25 | 10 25 |
| 5. Flammable liquids below ground—in excess of 1,000 gallons. | Tank Vent or fill opening of tank | 20 25 | 20 25 | 20 25 |
| 6. Flammable gas storage, either high pressure or low pressure. | 0 to 15,000 CF capacity In excess of 15,000 CF capacity | 10 25 | 25 50 | 25 50 |
| 7. Oxygen storage | 12,000 CF or less 4 | |||
| More than 12,000 CF 5 | ||||
| 8. Fast burning solids such as ordinary lumber, excelsior or paper | 50 | 50 | 50 | |
| 9. Slow burning solids such as heavy timber or coal | 25 | 25 | 25 | |
| 10. Open flames and other sources of ignition | 25 | 25 | 25 | |
| 11. Air compressor intakes or inlets to ventilating or air-conditioning equipment | 50 | 50 | 50 | |
| 12. Concentration of people 3 | 25 | 50 | 50 | |
| 1 Refer to NFPA No. 220 Standard Types of Building Construction for definitions of various types of construction. (1969 Ed.) | ||||
| 2 But not less than one-half the height of adjacent side wall of the structure. | ||||
| 3 In congested areas such as offices, lunchrooms, locker rooms, time-clock areas. | ||||
| 4 Refer to NFPA No. 51, gas systems for welding and cutting (1969). | ||||
| 5 Refer to NFPA No. 566, bulk oxygen systems at consumer sites (1969). |
For installations which require any operation of equipment by the user, legible instructions shall be maintained at operating locations.
The equipment and functioning of each charged gaseous hydrogen system shall be maintained in a safe operating condition in accordance with the requirements of this section. The area within 15 feet of any hydrogen container shall be kept free of dry vegetation and combustible material.
Permanently installed containers shall be provided with substantial noncombustible supports securely anchored on firm noncombustible foundations. Steel supports in excess of 18 inches in height shall be protected with a protective coating having a 2-hour fire-resistance rating.
Each container shall be legibly marked to indicate “LIQUEFIED HYDROGEN—FLAMMABLE GAS.”
Department of Transportation Regulations shall be equipped with safety relief devices as required in the U.S. Department of Transportation Specifications and Regulations. Safety relief devices shall be sized in accordance with the requirements of CGA Pamphlet S-1, Safety Relief Device Standards, part 1, Compressed Gas Cylinders and part 2, Cargo and Portable Tank Containers.
496-1967, Standard for Purged Enclosures for Electrical Equipment in Hazardous Locations,
The liquefied hydrogen container and associated piping shall be electrically bonded and grounded.
| Nature of location | Size of hydrogen storage (capacity in gallons) | |||
|---|---|---|---|---|
| 39.63 (150 liters) to 50 | 51 to 300 | 301 to 600 | In excess of 600 | |
| Outdoors | I | I | I | I. |
| In a separate building | II | II | II | Not permitted. |
| In a special room | III | III | Not permitted | Do. |
| Inside buildings not in a special room and exposed to other occupancies | IV | Not permitted | ......do | Do. |
| Note: This table does not apply to the storage in dewars of the type generally used in laboratories for experimental purposes. |
| Type of exposure | Liquefied hydrogen storage (capacity in gallons) | ||
|---|---|---|---|
| 39.63 (150 liters) to 3,500 | 3,501 to 15,000 | 15,001 to 30,000 | |
| 1. Fire-resistive building and fire walls 3 | 5 | 5 | 5 |
| 2. Noncombustible building 3 | 25 | 50 | 75 |
| 3. Other buildings 3 | 50 | 75 | 100 |
| 4. Wall openings, air-compressor intakes, inlets for air-conditioning or ventilating equipment | 75 | 75 | 75 |
| 5. Flammable liquids (above ground and vent or fill openings if below ground) (see 513 and 514) | 50 | 75 | 100 |
| 6. Between stationary liquefied hydrogen containers | 5 | 5 | 5 |
| 7. Flammable gas storage | 50 | 75 | 100 |
| 8. Liquid oxygen storage and other oxidizers (see 513 and 514) | 100 | 100 | 100 |
| 9. Combustible solids | 50 | 75 | 100 |
| 10. Open flames, smoking and welding | 50 | 50 | 50 |
| 11. Concentrations of people | 75 | 75 | 75 |
| 1 The distance in Nos. 2, 3, 5, 7, 9, and 12 in Table H-4 may be reduced where protective structures, such as firewalls equal to height of top of the container, to safeguard the liquefied hydrogen storage system, are located between the liquefied hydrogen storage installation and the exposure. | |||
| 2 Where protective structures are provided, ventilation and confinement of product should be considered. The 5-foot distance in Nos. 1 and 6 facilitates maintenance and enhances ventilation. | |||
| 3 Refer to Standard Types of Building Construction, NFPA No. 220-1969 for definitions of various types of construction. | |||
| In congested areas such as offices, lunchrooms, locker rooms, time-clock areas. |
For installation which require any operation of equipment by the user, legible instructions shall be maintained at operating locations.
A qualified person shall be in attendance at all times while the mobile hydrogen supply unit is being unloaded.
Each mobile liquefied hydrogen supply unit used as part of a hydrogen system shall be adequately secured to prevent movement.
The mobile liquefied hydrogen supply unit shall be grounded for static electricity.
The equipment and functioning of each charged liquefied hydrogen system shall be maintained in a safe operating condition in accordance with the requirements of this section. Weeds or similar combustibles shall not be permitted within 25 feet of any liquefied hydrogen equipment.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49746, Oct. 24, 1978; 53 FR 12121, Apr. 12, 1988; 55 FR 32015, Aug. 6, 1990; 58 FR 35309, June 30, 1993; 61 FR 9236, 9237, Mar. 7, 1996; 69 FR 31881, June 8, 2004; 72 FR 71069, Dec. 14, 2007]
This section applies to the installation of bulk oxygen systems on industrial and institutional consumer premises. This section does not apply to oxygen manufacturing plants or other establishments operated by the oxygen supplier or his agent for the purpose of storing oxygen and refilling portable containers, trailers, mobile supply trucks, or tank cars, nor to systems having capacities less than those stated in paragraph (b)(1) of this section.
A bulk oxygen system is an assembly of equipment, such as oxygen storage containers, pressure regulators, safety devices, vaporizers, manifolds, and interconnecting piping, which has storage capacity of more than 13,000 cubic feet of oxygen, Normal Temperature and Pressure (NTP), connected in service or ready for service, or more than 25,000 cubic feet of oxygen (NTP) including unconnected reserves on hand at the site. The bulk oxygen system terminates at the point where oxygen at service pressure first enters the supply line. The oxygen containers may be stationary or movable, and the oxygen may be stored as gas or liquid.
Bulk oxygen storage systems shall be located above ground out of doors, or shall be installed in a building of noncombustible construction, adequately vented, and used for that purpose exclusively. The location selected shall be such that containers and associated equipment shall not be exposed by electric power lines, flammable or combustible liquid lines, or flammable gas lines.
The system shall be located so that it is readily accessible to mobile supply equipment at ground level and to authorized personnel.
Where oxygen is stored as a liquid, noncombustible surfacing shall be provided in an area in which any leakage of liquid oxygen might fall during operation of the system and filling of a storage container. For purposes of this paragraph, asphaltic or bituminous paving is considered to be combustible.
When locating bulk oxygen systems near above-ground flammable or combustible liquid storage which may be either indoors or outdoors, it is advisable to locate the system on ground higher than the flammable or combustible liquid storage.
Where it is necessary to locate a bulk oxygen system on ground lower than adjacent flammable or combustible liquid storage suitable means shall be taken (such as by diking, diversion curbs, or grading) with respect to the adjacent flammable or combustible liquid storage to prevent accumulation of liquids under the bulk oxygen system.
The minimum distance from any bulk oxygen storage container to exposures, measured in the most direct line except as indicated in paragraphs (b)(3) (vi) and (viii) of this section, shall be as indicated in paragraphs (b)(3) (ii) to (xviii) of this section inclusive.
Fifty feet from any combustible structures.
Twenty-five feet from any structures with fire-resistive exterior walls or sprinklered buildings of other construction, but not less than one-half the height of adjacent side wall of the structure.
At least 10 feet from any opening in adjacent walls of fire resistive structures. Spacing from such structures shall be adequate to permit maintenance, but shall not be less than 1 foot.
| Distance (feet) | Capacity (gallons) |
|---|---|
| 50 | 0 to 1000. |
| 90 | 1001 or more. |
| Distance measured horizontally from oxygen storage container to flammable liquid tank (feet) | Distance from oxygen storage container to filling and vent connections or openings to flammable liquid tank (feet) | Capacity gallons |
|---|---|---|
| 15 | 50 | 0 to 1000. |
| 30 | 50 | 1001 or more. |
| Distance (feet) | Capacity (gallons) |
|---|---|
| 25 | 0 to 1000. |
| 50 | 1001 or more. |
| Distance measured horizontally from oxygen storage container to combustible liquid tank (feet) | Distance from oxygen storage container to filling and vent connections or openings to combustible liquid tank (feet) |
|---|---|
| 15 | 40. |
| Distance (feet) | Capacity (cu. ft. NTP) |
|---|---|
| 50 | Less than 5000. |
| 90 | 5000 or more. |
Fifty feet from solid materials which burn rapidly, such as excelsior or paper.
Twenty-five feet from solid materials which burn slowly, such as coal and heavy timber.
Seventy-five feet in one direction and 35 feet in approximately 90° direction from confining walls (not including firewalls less than 20 feet high) to provide adequate ventilation in courtyards and similar confining areas.
Twenty-five feet from congested areas such as offices, lunchrooms, locker rooms, time clock areas, and similar locations where people may congregate.
The distances in paragraphs (b)(3) (ii), (iii), (v) to (xi) inclusive, of this section do not apply where protective structures such as firewalls of adequate height to safeguard the oxygen storage systems are located between the bulk oxygen storage installation and the exposure. In such cases, the bulk oxygen storage installation may be a minimum distance of 1 foot from the firewall.
Permanently installed containers shall be provided with substantial noncombustible supports on firm noncombustible foundations.
Liquid oxygen storage containers shall be fabricated from materials meeting the impact test requirements of paragraph UG-84 of ASME Boiler and Pressure Vessel Code, section VIII—Unfired Pressure Vessels—1968, which is incorporated by reference as specified in § 1910.6. Containers operating at pressures above 15 pounds per square inch gage (p.s.i.g.) shall be designed, constructed, and tested in accordance with appropriate requirements of ASME Boiler and Pressure Vessel Code, section VII—Unfired Pressure Vessels—1968. Insulation surrounding the liquid oxygen container shall be noncombustible.
High- pressure gaseous oxygen containers shall comply with one of the following:
Piping, tubing, and fittings shall be suitable for oxygen service and for the pressures and temperatures involved.
Piping and tubing shall conform to section 2—Gas and Air Piping Systems of Code for Pressure Piping, ANSI, B31.1-1967 with addenda B31.10a-1969, which is incorporated by reference as specified in § 1910.6.
Piping or tubing for operating temperatures below −20 °F. shall be fabricated from materials meeting the impact test requirements of paragraph UG-84 of ASME Boiler and Pressure Vessel Code, Section VIII—Unfired Pressure Vessels—1968, when tested at the minimum operating temperature to which the piping may be subjected in service.
Bulk oxygen storage containers, regardless of design pressure shall be equipped with safety relief devices as required by the ASME code or the DOT specifications and regulations.
Bulk oxygen storage containers designed and constructed in accordance with DOT specification shall be equipped with safety relief devices as required thereby.
Bulk oxygen storage containers designed and constructed in accordance with the ASME Boiler and Pressure Vessel Code, section VIII—Unfired Pressure Vessel—1968 shall be equipped with safety relief devices meeting the provisions of the Compressed Gas Association Pamphlet “Safety Relief Device Standards for Compressed Gas Storage Containers,” S-1, part 3, which is incorporated by reference as specified in § 1910.6.
Insulation casings on liquid oxygen containers shall be equipped with suitable safety relief devices.
All safety relief devices shall be so designed or located that moisture cannot collect and freeze in a manner which would interfere with proper operation of the device.
The vaporizer shall be anchored and its connecting piping be sufficiently flexible to provide for the effect of expansion and contraction due to temperature changes.
The vaporizer and its piping shall be adequately protected on the oxygen and heating medium sections with safety relief devices.
Heat used in an oxygen vaporizer shall be indirectly supplied only through media such as steam, air, water, or water solutions which do not react with oxygen.
If electric heaters are used to provide the primary source of heat, the vaporizing system shall be electrically grounded.
Equipment making up a bulk oxygen system shall be cleaned in order to remove oil, grease or other readily oxidizable materials before placing the system in service.
Joints in piping and tubing may be made by welding or by use of flanged, threaded, slip, or compression fittings. Gaskets or thread sealants shall be suitable for oxygen service.
Valves, gages, regulators, and other accessories shall be suitable for oxygen service.
Installation of bulk oxygen systems shall be supervised by personnel familiar with proper practices with reference to their construction and use.
After installation all field erected piping shall be tested and proved gas tight at maximum operating pressure. Any medium used for testing shall be oil free and nonflammable.
Storage containers, piping, valves, regulating equipment, and other accessories shall be protected against physical damage and against tampering.
Any enclosure containing oxygen control or operating equipment shall be adequately vented.
The bulk oxygen storage location shall be permanently placarded to indicate: “OXYGEN—NO SMOKING—NO OPEN FLAMES”, or an equivalent warning.
Bulk oxygen installations are not hazardous locations as defined and covered in subpart S of this part. Therefore, general purpose or weatherproof types of electrical wiring and equipment are acceptable depending upon whether the installation is indoors or outdoors. Such equipment shall be installed in accordance with the applicable provisions of subpart S of this part.
For installations which require any operation of equipment by the user, legible instructions shall be maintained at operating locations.
The equipment and functioning of each charged bulk oxygen system shall be maintained in a safe operating condition in accordance with the requirements of this section. Wood and long dry grass shall be cut back within 15 feet of any bulk oxygen storage container.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49746, Oct. 24, 1978; 61 FR 9237, Mar. 7, 1996]
The piped systems for the in-plant transfer and distribution of nitrous oxide shall be designed, installed, maintained, and operated in accordance with Compressed Gas Association Pamphlet G-8.1-1964, which is incorporated by reference as specified in § 1910.6.
[39 FR 23502, June 27, 1974, as amended at 61 FR 9237, Mar. 7, 1996]
As used in this section:
Flammable liquids shall be stored in a tank or in a container that complies with paragraph (d)(2) of this section.
means Saybolt Universal Seconds as determined by the Standard Method of Test for Saybolt Viscosity (ASTM D-88-56), and may be determined by use of the SUS conversion tables specified in ASTM Method D2161-66 following determination of viscosity in accordance with the procedures specified in the Standard Method of Test for Viscosity of Transparent and Opaque Liquids (ASTM D445-65).
142, Standard for Steel Aboveground Tanks for Flammable and Combustible Liquids, 1968; No. 58, Standard for Steel Underground Tanks for Flammable and Combustible Liquids, Fifth Edition, December 1961; or No. 80, Standard for Steel Inside Tanks for Oil-Burner Fuel, September 1963.
650, Welded Steel Tanks for Oil Storage, Third Edition, 1966.
12B, Specification for Bolted Production Tanks, Eleventh Edition, May 1958, and Supplement 1, March 1962; No. 12D, Specification for Large Welded Production Tanks, Seventh Edition, August 1957; or No. 12F, Specification for Small Welded Production Tanks, Fifth Edition, March 1961. Tanks built in accordance with these standards shall be used only as production tanks for storage of crude petroleum in oil-producing areas.
620. Recommended Rules for the Design and Construction of Large, Welded, Low-Pressure Storage Tanks, Third Edition, 1966.
This paragraph may be used for operating pressures not exceeding 1 p.s.i.g.
When tanks are not designed in accordance with the American Petroleum Institute, American Society of Mechanical Engineers, or the Underwriters' Laboratories, Inc.'s, standards, or if corrosion is anticipated beyond that provided for in the design formulas used, additional metal thickness or suitable protective coatings or linings shall be provided to compensate for the corrosion loss expected during the design life of the tank.
Tanks of 3,000 bbls (barrels). capacity or less containing crude petroleum in crude-producing areas and outside aboveground atmospheric tanks under 1,000 gallons capacity containing other than Category 1 flammable liquids may have open vents. ( See paragraph (b)(2)(vi)( b ) of this section.)
| Square feet | CFH | Square feet | CFH | Square feet | CFH |
|---|---|---|---|---|---|
| 20 | 21,100 | 200 | 211,000 | 1,000 | 524,000 |
| 30 | 31,600 | 250 | 239,000 | 1,200 | 557,000 |
| 40 | 42,100 | 300 | 265,000 | 1,400 | 587,000 |
| 50 | 52,700 | 350 | 288,000 | 1,600 | 614,000 |
| 60 | 63,200 | 400 | 312,000 | 1,800 | 639,000 |
| 70 | 73,700 | 500 | 354,000 | 2,000 | 662,000 |
| 80 | 84,200 | 600 | 392,000 | 2,400 | 704,000 |
| 90 | 94,800 | 700 | 428,000 | 2,800 | 742,000 |
| 100 | 105,000 | 800 | 462,000 | and | |
| 120 | 126,000 | 900 | 493,000 | over | |
| 140 | 147,000 | 1,000 | 524,000 | ||
| 160 | 168,000 | ||||
| 180 | 190,000 | ||||
| 200 | 211,000 |
0.82
Where;
CFH
A
L√M
V
L
M
0.5 for drainage in accordance with subdivision (vii)( b ) of this subparagraph for tanks over 200 square feet of wetted area.
0.3 for approved water spray.
0.3 for approved insulation.
0.15 for approved water spray with approved insulation.
The area surrounding a tank or a group of tanks shall be provided with drainage as in subdivision ( b ) of this subdivision, or shall be diked as provided in subdivision ( c ) of this subdivision, to prevent accidental discharge of liquid from endangering adjoining property or reaching waterways.
Where protection of adjoining property or waterways is by means of a natural or manmade drainage system, such systems shall comply with the following:
Where protection of adjoining property or waterways is accomplished by retaining the liquid around the tank by means of a dike, the volume of the diked area shall comply with the following requirements:
Excavation for underground storage tanks shall be made with due care to avoid undermining of foundations of existing structures. Underground tanks or tanks under buildings shall be so located with respect to existing building foundations and supports that the loads carried by the latter cannot be transmitted to the tank. The distance from any part of a tank storing Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), to the nearest wall of any basement or pit shall be not less than 1 foot, and to any property line that may be built upon, not less than 3 feet. The distance from any part of a tank storing Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids to the nearest wall of any basement, pit or property line shall be not less than 1 foot.
Underground tanks shall be set on firm foundations and surrounded with at least 6 inches of noncorrosive, inert materials such as clean sand, earth, or gravel well tamped in place. The tank shall be placed in the hole with care since dropping or rolling the tank into the hole can break a weld, puncture or damage the tank, or scrape off the protective coating of coated tanks. Tanks shall be covered with a minimum of 2 feet of earth, or shall be covered with not less than 1 foot of earth, on top of which shall be placed a slab of reinforced concrete not less than 4 inches thick. When underground tanks are, or are likely to be, subject to traffic, they shall be protected against damage from vehicles passing over them by at least 3 feet of earth cover, or 18 inches of well-tamped earth, plus 6 inches of reinforced concrete or 8 inches of asphaltic concrete. When asphaltic or reinforced concrete paving is used as part of the protection, it shall extend at least 1 foot horizontally beyond the outline of the tank in all directions.
Corrosion protection for the tank and its piping shall be provided by one or more of the following methods:
Each tank shall be vented through piping adequate in size to prevent blow-back of vapor or liquid at the fill opening while the tank is being filled. Vent pipes shall be not less than 1 1/4 inch nominal inside diameter.
| Maximum flow GPM | Pipe length 1 | ||
|---|---|---|---|
| 50 feet | 100 feet | 200 feet | |
| Inches | Inches | Inches | |
| 100 | 1 1 ⁄ 4 | 1 1 ⁄ 4 | 1 1 ⁄ 4 |
| 200 | 1 1 ⁄ 4 | 1 1 ⁄ 4 | 1 1 ⁄ 4 |
| 300 | 1 1 ⁄ 4 | 1 1 ⁄ 4 | 1 1 ⁄ 2 |
| 400 | 1 1 ⁄ 4 | 1 1 ⁄ 2 | 2 |
| 500 | 1 1 ⁄ 2 | 1 1 ⁄ 2 | 2 |
| 600 | 1 1 ⁄ 2 | 2 | 2 |
| 700 | 2 | 2 | 2 |
| 800 | 2 | 2 | 3 |
| 900 | 2 | 2 | 3 |
| 1,000 | 2 | 2 | 3 |
| 1 Vent lines of 50 ft., 100 ft., and 200 ft. of pipe plus 7 ells. |
Tanks shall not be permitted inside of buildings except as provided in paragraphs (e), (g), (h), or (i) of this section.
Vents for tanks inside of buildings shall be as provided in subparagraphs (2) (iv), (v), (vi)( b ), and (3)(iv) of this paragraph, except that emergency venting by the use of weak roof seams on tanks shall not be permitted. Vents shall discharge vapors outside the buildings.
Vent piping shall be constructed in accordance with paragraph (c) of this section.
Tank supports shall be installed on firm foundations. Tank supports shall be of concrete, masonry, or protected steel. Single wood timber supports (not cribbing) laid horizontally may be used for outside aboveground tanks if not more than 12 inches high at their lowest point.
Steel supports or exposed piling shall be protected by materials having a fire resistance rating of not less than 2 hours, except that steel saddles need not be protected if less than 12 inches high at their lowest point. Water spray protection or its equivalent may be used in lieu of fire-resistive materials to protect supports.
The design of the supporting structure for tanks such as spheres shall receive special engineering consideration.
Every tank shall be so supported as to prevent the excessive concentration of loads on the supporting portion of the shell.
Tanks shall rest on the ground or on foundations made of concrete, masonry, piling, or steel. Tank foundations shall be designed to minimize the possibility of uneven settling of the tank and to minimize corrosion in any part of the tank resting on the foundation.
Where a tank is located in an area that may be subjected to flooding, the applicable precautions outlined in this subdivision shall be observed.
The Assistant Secretary or his designated representative shall make periodic inspections of all plants where the storage of flammable liquids is such as to require compliance with the foregoing requirements, in order to assure the following:
In areas subject to earthquakes, the tank supports and connections shall be designed to resist damage as a result of such shocks.
In locations where flammable vapors may be present, precautions shall be taken to prevent ignition by eliminating or controlling sources of ignition. Sources of ignition may include open flames, lightning, smoking, cutting and welding, hot surfaces, frictional heat, sparks (static, electrical, and mechanical), spontaneous ignition, chemical and physical-chemical reactions, and radiant heat.
All tanks, whether shop built or field erected, shall be strength tested before they are placed in service in accordance with the applicable paragraphs of the code under which they were built. The American Society of Mechanical Engineers (ASME) code stamp, American Petroleum Institute (API) monogram, or the label of the Underwriters' Laboratories, Inc., on a tank shall be evidence of compliance with this strength test. Tanks not marked in accordance with the above codes shall be strength tested before they are placed in service in accordance with good engineering principles and reference shall be made to the sections on testing in the codes listed in subparagraphs (1) (iii)( a ), (iv)( b ), or (v)( b ) of this paragraph.
When the vertical length of the fill and vent pipes is such that when filled with liquid the static head imposed upon the bottom of the tank exceeds 10 pounds per square inch, the tank and related piping shall be tested hydrostatically to a pressure equal to the static head thus imposed.
In addition to the strength test called for in subdivisions (i) and (ii) of this subparagraph, all tanks and connections shall be tested for tightness. Except for underground tanks, this tightness test shall be made at operating pressure with air, inert gas, or water prior to placing the tank in service. In the case of field-erected tanks the strength test may be considered to be the test for tank tightness. Underground tanks and piping, before being covered, enclosed, or placed in use, shall be tested for tightness hydrostatically, or with air pressure at not less than 3 pounds per square inch and not more than 5 pounds per square inch.
All leaks or deformations shall be corrected in an acceptable manner before the tank is placed in service. Mechanical caulking is not permitted for correcting leaks in welded tanks except pinhole leaks in the roof.
Tanks to be operated at pressures below their design pressure may be tested by the applicable provisions of subdivision (i) or (ii) of this subparagraph, based upon the pressure developed under full emergency venting of the tank.
The design (including selection of materials) fabrication, assembly, test, and inspection of piping systems containing flammable liquids shall be suitable for the expected working pressures and structural stresses. Conformity with the applicable provisions of Pressure Piping, ANSI B31 series and the provisions of this paragraph, shall be considered prima facie evidence of compliance with the foregoing provisions.
This paragraph does not apply to any of the following:
As used in this paragraph, piping systems consist of pipe, tubing, flanges, bolting, gaskets, valves, fittings, the pressure containing parts of other components such as expansion joints and strainers, and devices which serve such purposes as mixing, separating, snubbing, distributing, metering, or controlling flow.
Materials for piping, valves, or fittings shall be steel, nodular iron, or malleable iron, except as provided in paragraph (c)(2) (ii), (iii) and (iv) of this section.
Materials other than steel, nodular iron, or malleable iron may be used underground, or if required by the properties of the flammable liquid handled. Material other than steel, nodular iron, or malleable iron shall be designed to specifications embodying principles recognized as good engineering practices for the material used.
Piping, valves, and fittings may have combustible or noncombustible linings.
When low-melting point materials such as aluminum and brass or materials that soften on fire exposure such as plastics, or non-ductile materials such as cast iron, are necessary, special consideration shall be given to their behavior on fire exposure. If such materials are used in above ground piping systems or inside buildings, they shall be suitably protected against fire exposure or so located that any spill resulting from the failure of these materials could not unduly expose persons, important buildings or structures or can be readily controlled by remote valves.
Joints shall be made liquid tight. Welded or screwed joints or approved connectors shall be used. Threaded joints and connections shall be made up tight with a suitable lubricant or piping compound. Pipe joints dependent upon the friction characteristics of combustible materials for mechanical continuity of piping shall not be used inside buildings. They may be used outside of buildings above or below ground. If used above ground, the piping shall either be secured to prevent disengagement at the fitting or the piping system shall be so designed that any spill resulting from such disengagement could not unduly expose persons, important buildings or structures, and could be readily controlled by remote valves.
Piping systems shall be substantially supported and protected against physical damage and excessive stresses arising from settlement, vibration, expansion, or contraction.
All piping for flammable liquids, both aboveground and underground, where subject to external corrosion, shall be painted or otherwise protected.
Piping systems shall contain a sufficient number of valves to operate the system properly and to protect the plant. Piping systems in connection with pumps shall contain a sufficient number of valves to control properly the flow of liquid in normal operation and in the event of physical damage. Each connection to pipelines, by which equipments such as tankcars or tank vehicles discharge liquids by means of pumps into storage tanks, shall be provided with a check valve for automatic protection against backflow if the piping arrangement is such that backflow from the system is possible.
All piping before being covered, enclosed, or placed in use shall be hydrostatically tested to 150 percent of the maximum anticipated pressure of the system, or pneumatically tested to 110 percent of the maximum anticipated pressure of the system, but not less than 5 pounds per square inch gage at the highest point of the system. This test shall be maintained for a sufficient time to complete visual inspection of all joints and connections, but for at least 10 minutes.
This paragraph shall apply only to the storage of flammable liquids in drums or other containers (including flammable aerosols) not exceeding 60 gallons individual capacity and those portable tanks not exceeding 660 gallons individual capacity.
This paragraph shall not apply to the following:
Only approved containers and portable tanks shall be used. Metal containers and portable tanks meeting the requirements of and containing products authorized by chapter I, title 49 of the Code of Federal Regulations (regulations issued by the Hazardous Materials Regulations Board, Department of Transportation), shall be deemed to be acceptable.
Each portable tank shall be provided with one or more devices installed in the top with sufficient emergency venting capacity to limit internal pressure under fire exposure conditions to 10 p.s.i.g., or 30 percent of the bursting pressure of the tank, whichever is greater. The total venting capacity shall be not less than that specified in paragraphs (b)(2)(v) ( c ) or ( e ) of this section. At least one pressure-activated vent having a minimum capacity of 6,000 cubic feet of free air (14.7 p.s.i.a. and 60 °F.) shall be used. It shall be set to open at not less than 5 p.s.i.g. If fusible vents are used, they shall be actuated by elements that operate at a temperature not exceeding 300 °F.
Flammable liquid containers shall be in accordance with Table H-12, except that glass or plastic containers of no more than 1-gallon capacity may be used for a Category 1 or 2 flammable liquid if:
| Container type | Category 1 | Category 2 | Category 3 | Category 4 |
|---|---|---|---|---|
| Glass or approved plastic | 1 pt | 1 qt | 1 gal | 1 gal. |
| Metal (other than DOT drums) | 1 gal | 5 gal | 5 gal | 5 gal. |
| Safety cans | 2 gal | 5 gal | 5 gal | 5 gal. |
| Metal drums (DOT specifications) | 60 gal | 60 gal | 60 gal | 60 gal. |
| Approved portable tanks | 660 gal | 660 gal | 660 gal | 660 gal. |
| Note: Container exemptions: (a) Medicines, beverages, foodstuffs, cosmetics, and other common consumer items, when packaged according to commonly accepted practices, shall be exempt from the requirements of 1910.106(d)(2)(i) and (ii). |
Not more than 60 gallons of Category 1, 2, or 3 flammable liquids, nor more than 120 gallons of Category 4 flammable liquids may be stored in a storage cabinet.
Storage cabinets shall be designed and constructed to limit the internal temperature to not more than 325 °F. when subjected to a 10-minute fire test using the standard time-temperature curve as set forth in Standard Methods of Fire Tests of Building Construction and Materials, NFPA 251-1969, which is incorporated by reference as specified in § 1910.6. All joints and seams shall remain tight and the door shall remain securely closed during the fire test. Cabinets shall be labeled in conspicuous lettering, “Flammable—Keep Fire Away.”
Inside storage rooms shall be constructed to meet the required fire-resistive rating for their use. Such construction shall comply with the test specifications set forth in Standard Methods of Fire Tests of Building Construction and Materials, NFPA 251-1969. Where an automatic sprinkler system is provided, the system shall be designed and installed in an acceptable manner. Openings to other rooms or buildings shall be provided with noncombustible liquid-tight raised sills or ramps at least 4 inches in height, or the floor in the storage area shall be at least 4 inches below the surrounding floor. Openings shall be provided with approved self-closing fire doors. The room shall be liquid-tight where the walls join the floor. A permissible alternate to the sill or ramp is an open-grated trench inside of the room which drains to a safe location. Where other portions of the building or other properties are exposed, windows shall be protected as set forth in the Standard for Fire Doors and Windows, NFPA No. 80-1968, which is incorporated by reference as specified in § 1910.6, for Class E or F openings. Wood at least 1 inch nominal thickness may be used for shelving, racks, dunnage, scuffboards, floor overlay, and similar installations.
Storage in inside storage rooms shall comply with Table H-13.
| Fire protection 1 provided | Fire resistance | Maximum size | Total allowable quantities (gals./sq. ft./floor area) |
|---|---|---|---|
| Yes | 2 hours | 500 sq. ft | 10 |
| No | 2 hours | 500 sq. ft | 5 |
| Yes | 1 hour | 150 sq. ft | 4 |
| No | 1 hour | 150 sq. ft | 2 |
| 1 Fire protection system shall be sprinkler, water spray, carbon dioxide, or other system. |
Electrical wiring and equipment located in inside storage rooms used for Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), shall be approved under subpart S of this part for Class I, Division 2 Hazardous Locations; for Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) and Category 4 flammable liquids, shall be approved for general use.
Every inside storage room shall be provided with either a gravity or a mechanical exhaust ventilation system. Such system shall be designed to provide for a complete change of air within the room at least six times per hour. If a mechanical exhaust system is used, it shall be controlled by a switch located outside of the door. The ventilating equipment and any lighting fixtures shall be operated by the same switch. A pilot light shall be installed adjacent to the switch if Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), are dispensed within the room. Where gravity ventilation is provided, the fresh air intake, as well as the exhaust outlet from the room, shall be on the exterior of the building in which the room is located.
In every inside storage room there shall be maintained one clear aisle at least 3 feet wide. Containers over 30 gallons capacity shall not be stacked one upon the other. Dispensing shall be by approved pump or self-closing faucet only.
Flammable liquids, including stock for sale, shall not be stored so as to limit use of exits, stairways, or areas normally used for the safe egress of people.
The storage of flammable liquids in containers or portable tanks shall comply with subdivisions (iii) through (v) of this subparagraph.
Storage shall be prohibited except that which is required for maintenance and operation of building and operation of equipment. Such storage shall be kept in closed metal containers stored in a storage cabinet or in safety cans or in an inside storage room not having a door that opens into that portion of the building used by the public.
A maximum of 1,100 gallons of flammable liquids may be located adjacent to buildings located on the same premises and under the same management provided the provisions of subdivisions ( a ) and ( b ) of this subdivision are complied with.
The storage area shall be graded in a manner to divert possible spills away from buildings or other exposures or shall be surrounded by a curb at least 6 inches high. When curbs are used, provisions shall be made for draining of accumulations of ground or rain water or spills of flammable liquids. Drains shall terminate at a safe location and shall be accessible to operation under fire conditions.
The storage area shall be protected against tampering or trespassers where necessary and shall be kept free of weeds, debris and other combustible material not necessary to the storage.
When sprinklers are provided, they shall be installed in accordance with § 1910.159.
Open flames and smoking shall not be permitted in flammable liquid storage areas.
Materials which will react with water shall not be stored in the same room with flammable liquids.
This paragraph shall apply to those industrial plants where:
Where portions of such plants involve chemical reactions such as oxidation, reduction, halogenation, hydrogenation, alkylation, polymerization, and other chemical processes, those portions of the plant shall be in accordance with paragraph (h) of this section.
This subparagraph shall be applicable to those portions of an industrial plant where the use and handling of flammable liquids is only incidental to the principal business, such as automobile assembly, construction of electronic equipment, furniture manufacturing, or other similar activities.
Flammable liquids shall be stored in tanks or closed containers.
Areas in which flammable liquids are transferred from one tank or container to another container shall be separated from other operations in the building by adequate distance or by construction having adequate fire resistance. Drainage or other means shall be provided to control spills. Adequate natural or mechanical ventilation shall be provided.
This subparagraph shall be applicable in those portions of industrial plants where flammable liquids are handled or used in unit physical operations such as mixing, drying, evaporating, filtering, distillation, and similar operations which do not involve chemical change. Examples are plants compounding cosmetics, pharmaceuticals, solvents, cleaning fluids, insecticides, and similar types of activities.
Industrial plants shall be located so that each building or unit of equipment is accessible from at least one side for firefighting and fire control purposes. Buildings shall be located with respect to lines of adjoining property which may be built upon as set forth in paragraph (h)(2) (i) and (ii) of this section except that the blank wall referred to in paragraph (h)(2)(ii) of this section shall have a fire resistance rating of at least 2 hours.
Areas where unstable liquids are handled or small scale unit chemical processes are carried on shall be separated from the remainder of the plant by a fire wall of 2-hour minimum fire resistance rating.
The storage, transfer, and handling of liquid shall comply with paragraph (h)(4) of this section.
Portable fire extinguishment and control equipment shall be provided in such quantities and types as are needed for the special hazards of operation and storage.
Water shall be available in volume and at adequate pressure to supply water hose streams, foam-producing equipment, automatic sprinklers, or water spray systems as the need is indicated by the special hazards of operation, dispensing and storage.
Special extinguishing equipment such as that utilizing foam, inert gas, or dry chemical shall be provided as the need is indicated by the special hazards of operation dispensing and storage.
Where the need is indicated by special hazards of operation, flammable liquid processing equipment, major piping, and supporting steel shall be protected by approved water spray systems, deluge systems, approved fire-resistant coatings, insulation, or any combination of these.
All plant fire protection facilities shall be adequately maintained and periodically inspected and tested to make sure they are always in satisfactory operating condition, and they will serve their purpose in time of emergency.
Adequate precautions shall be taken to prevent the ignition of flammable vapors. Sources of ignition include but are not limited to open flames; lightning; smoking; cutting and welding; hot surfaces; frictional heat; static, electrical, and mechanical sparks; spontaneous ignition, including heat-producing chemical reactions; and radiant heat.
Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), shall not be dispensed into containers unless the nozzle and container are electrically interconnected. Where the metallic floorplate on which the container stands while filling is electrically connected to the fill stem or where the fill stem is bonded to the container during filling operations by means of a bond wire, the provisions of this section shall be deemed to have been complied with.
Hot work, such as welding or cutting operations, use of spark-producing power tools, and chipping operations shall be permitted only under supervision of an individual in responsible charge. The individual in responsible charge shall make an inspection of the area to be sure that it is safe for the work to be done and that safe procedures will be followed for the work specified.
Maintenance and operating practices shall be in accordance with established procedures which will tend to control leakage and prevent the accidental escape of flammable liquids. Spills shall be cleaned up promptly.
Adequate aisles shall be maintained for unobstructed movement of personnel and so that fire protection equipment can be brought to bear on any part of flammable liquid storage, use, or any unit physical operation.
Combustible waste material and residues in a building or unit operating area shall be kept to a minimum, stored in covered metal receptacles and disposed of daily.
Ground area around buildings and unit operating areas shall be kept free of weeds, trash, or other unnecessary combustible materials.
Containers of flammable liquids when piled one upon the other shall be separated by dunnage sufficient to provide stability and to prevent excessive stress on container walls. The height of the pile shall be consistent with the stability and strength of containers.
Rooms in which flammable liquids are stored or handled by pumps shall have exit facilities arranged to prevent occupants from being trapped in the event of fire.
Rooms in which Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), are stored or handled shall be heated only by means not constituting a source of ignition, such as steam or hot water. Rooms containing heating appliances involving sources of ignition shall be located and arranged to prevent entry of flammable vapors.
Tank vehicle and tank car loading or unloading facilities shall be separated from aboveground tanks, warehouses, other plant buildings or nearest line of adjoining property that may be built upon by a distance of 25 feet for Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), and 15 feet for Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) and Category 4 flammable liquids measured from the nearest position of any fill spout. Buildings for pumps or shelters for personnel may be a part of the facility.
Equipment such as piping, pumps, and meters used for the transfer of Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), between storage tanks and the fill stem of the loading rack shall not be used for the transfer of Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids.
Valves used for the final control for filling tank vehicles shall be of the self-closing type and manually held open except where automatic means are provided for shutting off the flow when the vehicle is full or after filling of a preset amount.
Tank car loading facilities where Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), are loaded through open domes shall be protected against stray currents by bonding the pipe to at least one rail and to the rack structure if of metal. Multiple lines entering the rack area shall be electrically bonded together. In addition, in areas where excessive stray currents are known to exist, all pipe entering the rack area shall be provided with insulating sections to electrically isolate the rack piping from the pipelines. No bonding between the tank car and the rack or piping is required during either loading or unloading of Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids.
Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), shall not be dispensed into containers unless the nozzle and container are electrically interconnected. Where the metallic floorplate on which the container stands while filling is electrically connected to the fill stem or where the fill stem is bonded to the container during filling operations by means of a bond wire, the provisions of this section shall be deemed to have been complied with.
The term wharf shall mean any wharf, pier, bulkhead, or other structure over or contiguous to navigable water used in conjunction with a bulk plant, the primary function of which is the transfer of flammable liquid cargo in bulk between the bulk plant and any tank vessel, ship, barge, lighter boat, or other mobile floating craft; and this subparagraph shall apply to all such installations except Marine Service Stations as covered in paragraph (g) of this section.
Substructure and deck shall be substantially designed for the use intended. Deck may employ any material which will afford the desired combination of flexibility, resistance to shock, durability, strength, and fire resistance. Heavy timber construction is acceptable.
Loading pumps capable of building up pressures in excess of the safe working pressure of cargo hose or loading arms shall be provided with bypasses, relief valves, or other arrangement to protect the loading facilities against excessive pressure. Relief devices shall be tested at not more than yearly intervals to determine that they function satisfactorily at the pressure at which they are set.
All pressure hoses and couplings shall be inspected at intervals appropriate to the service. The hose and couplings shall be tested with the hose extended and using the “inservice maximum operating pressures.” Any hose showing material deteriorations, signs of leakage, or weakness in its carcass or at the couplings shall be withdrawn from service and repaired or discarded.
Piping, valves, and fittings shall be in accordance with paragraph (c) of this section, with the following exceptions and additions:
Suitable portable fire extinguishers with a rating of not less than 12-BC shall be located within 75 feet of those portions of the facility where fires are likely to occur, such as hose connections, pumps, and separator tanks.
Loading or discharging shall not commence until the wharf superintendent and officer in charge of the tank vessel agree that the tank vessel is properly moored and all connections are properly made. Mechanical work shall not be performed on the wharf during cargo transfer, except under special authorization based on a review of the area involved, methods to be employed, and precautions necessary.
This paragraph (f)(5)(i) shall apply to areas where Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), are stored or handled. For areas where only Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids are stored or handled, the electrical equipment may be installed in accordance with the provisions of Subpart S of this part, for ordinary locations.
All electrical equipment and wiring shall be of a type specified by and shall be installed in accordance with subpart S of this part.
So far as it applies Table H-18 shall be used to delineate and classify hazardous areas for the purpose of installation of electrical equipment under normal circumstances. In Table H-18 a classified area shall not extend beyond an unpierced wall, roof, or other solid partition. The area classifications listed shall be based on the premise that the installation meets the applicable requirements of this section in all respects.
Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), shall not be handled, drawn, or dispensed where flammable vapors may reach a source of ignition. Smoking shall be prohibited except in designated localities. “No Smoking” signs shall be conspicuously posted where hazard from flammable liquid vapors is normally present.
Provision shall be made to prevent flammable liquids which may be spilled at loading or unloading points from entering public sewers and drainage systems, or natural waterways. Connection to such sewers, drains, or waterways by which flammable liquids might enter shall be provided with separator boxes or other approved means whereby such entry is precluded. Crankcase drainings and flammable liquids shall not be dumped into sewers, but shall be stored in tanks or tight drums outside of any building until removed from the premises.
Suitable fire-control devices, such as small hose or portable fire extinguishers, shall be available to locations where fires are likely to occur. Additional fire-control equipment may be required where a tank of more than 50,000 gallons individual capacity contains Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), and where an unusual exposure hazard exists from surrounding property. Such additional fire-control equipment shall be sufficient to extinguish a fire in the largest tank. The design and amount of such equipment shall be in accordance with approved engineering standards.
| Location | Class I Group D division | Extent of classified area |
|---|---|---|
| Tank vehicle and tank car: 1 | ||
| Loading through open dome | 1 | Within 3 feet of edge of dome, extending in all directions. |
| 2 | Area between 3 feet and 5 feet from edge of dome, extending in all directions. | |
| Loading through bottom connections with atmospheric venting | 1 | Within 3 feet of point of venting to atmosphere extending in all directions. |
| 2 | Area between 3 feet and 5 feet from point of venting to atmosphere, extending in all directions. Also up to 18 inches above grade within a horizontal radius of 10 feet from point of loading connection. | |
| Loading through closed dome with atmospheric venting | 1 2 | Within 3 feet of open end of vent, extending in all directions. Area between 3 feet and 5 feet from open end of vent, extending in all directions. Also within 3 feet of edge of dome, extending in all directions. |
| Loading through closed dome with vapor recovery | 2 | Within 3 feet of point of connection of both fill and vapor lines, extending in all directions. |
| Bottom loading with vapor recovery or any bottom unloading | 2 | Within 3 feet of point of connections extending in all directions. Also up to 18 inches above grade with in a horizontal radius of 10 feet from point of connection. |
| Drum and container filling: | ||
| Outdoors, or indoors with adequate ventilation | 1 | Within 3 feet of vent and fill opening, extending in all directions. |
| 2 | Area between 3 feet and 5 feet from vent or fill opening, extending in all directions. Also up to 18 inches above floor or grade level within a horizontal radius of 10 feet from vent or fill opening. | |
| Outdoors, or indoors with adequate ventilation | 1 | Within 3 feet of vent and fill opening, extending in all directions. |
| 2 | Area between 3 feet and 5 feet from vent or fill opening, extending in all directions. Also up to 18 inches above floor or grade level within a horizontal radius of 10 feet from vent or fill opening. | |
| Tank—Aboveground: | ||
| Shell, ends, or roof and dike area | 2 | Within 10 feet from shell, ends, or roof of tank, Area inside dikes to level of top of dike. |
| Vent | 1 | Within 5 feet of open end of vent, extending in all directions. |
| 2 | Area between 5 feet and 10 feet from open end of vent, extending in all directions. | |
| Floating roof | 1 | Area above the roof and within the shell. |
| Pits: | ||
| Without mechanical ventilation | 1 | Entire area within pit if any part is within a Division 1 or 2 classified area. |
| With mechanical ventilation | 2 | Entire area within pit if any part is within a Division 1 or 2 classified area. |
| Containing valves, fittings or piping, and not within a Division 1 or 2 classified area | 2 | Entire pit. |
| Pumps, bleeders, withdrawal fittings, meters and similar devices: | ||
| Indoors | 2 | Within 5 feet of any edge of such devices, extending in all directions. Also up to 3 feet above floor or grade level within 25 feet horizontally from any edge of such devices. |
| Outdoors | 2 | Within 3 feet of any edge of such devices, extending in all directions. Also up to 18 inches above grade level within 10 feet horizontally from any edge of such devices. |
| Storage and repair garage for tank vehicles | 1 | All pits or spaces below floor level. |
| 2 | Area up to 18 inches above floor or grade level for entire storage or repair garage. | |
| Drainage ditches, separators, impounding basins | 2 | Area up to 18 inches above ditch, separator or basin. Also up to 18 inches above grade within 15 feet horizontally from any edge. |
| Garages for other than tank vehicles | ( 2 ) | If there is any opening to these rooms within the extent of an outdoor classified area, the entire room shall be classified the same as the area classification at the point of the opening. |
| Outdoor drum storage | ( 2 ) | |
| Indoor warehousing where there is no flammable liquid transfer | ( 2 ) | If there is any opening to these rooms within the extent of an indoor classified are, the room shall be classified the same as if the wall, curb or partition did not exist. |
| Office and rest rooms | ( 2 ) | |
| 1 When classifying the extent of the area, consideration shall be given to the fact that tank cars or tank vehicles may be spotted at varying points. Therefore, the extremities of the loading or unloading positions shall be used. | ||
| 2 Ordinary. |
No delivery of any Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), shall be made into portable containers unless the container is constructed of metal, has a tight closure with screwed or spring cover, and is fitted with a spout or so designed so the contents can be poured without spilling.
Dispensing devices at automotive service stations shall be so located that all parts of the vehicle being served will be on the premises of the service station.
Approved dispensing units may be located inside of buildings. The dispensing area shall be separated from other areas in an approved manner. The dispensing unit and its piping shall be mounted either on a concrete island or protected against collision damage by suitable means and shall be located in a position where it cannot be struck by a vehicle descending a ramp or other slope out of control. The dispensing area shall be provided with an approved mechanical or gravity ventilation system. When dispensing units are located below grade, only approved mechanical ventilation shall be used and the entire dispensing area shall be protected by an approved automatic sprinkler system. Ventilating systems shall be electrically interlocked with gasoline dispensing units so that the dispensing units cannot be operated unless the ventilating fan motors are energized.
A clearly identified and easily accessible switch(es) or a circuit breaker(s) shall be provided at a location remote from dispensing devices, including remote pumping systems, to shut off the power to all dispensing devices in the event of an emergency.
After the completion of the installation, including any paving, that section of the pressure piping system between the pump discharge and the connection for the dispensing facility shall be tested for at least 30 minutes at the maximum operating pressure of the system. Such tests shall be repeated at 5-year intervals thereafter.
This paragraph (g)(5) shall apply to areas where Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), are stored or handled. For areas where Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids are stored or handled the electrical equipment may be installed in accordance with the provisions of subpart S of this part, for ordinary locations.
Heating equipment shall be installed as provided in paragraphs (g)(6) (ii) through (v) of this section.
Heating equipment may be installed in the conventional manner in an area except as provided in paragraph (g)(6) (iii), (iv), or (v) of this section.
Heating equipment may be installed in a special room separated from an area classified by Table H-19 by walls having a fire resistance rating of at least 1 hour and without any openings in the walls within 8 feet of the floor into an area classified in Table H-19. This room shall not be used for combustible storage and all air for combustion purposes shall come from outside the building.
Heating equipment using gas or oil fuel may be installed in the lubrication, sales, or service room where there is no dispensing or transferring of Category 1 or 2 flammable liquids or 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), provided the bottom of the combustion chamber is at least 18 inches above the floor and the heating equipment is protected from physical damage by vehicles. Heating equipment using gas or oil fuel listed for use in garages may be installed in the lubrication or service room where Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), are dispensed provided the equipment is installed at least 8 feet above the floor.
Electrical heating equipment shall conform to paragraph (g)(5) of this section.
Provision shall be made in the area where Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), are dispensed to prevent spilled liquids from flowing into the interior of service station buildings. Such provision may be by grading driveways, raising door sills, or other equally effective means. Crankcase drainings and flammable liquids shall not be dumped into sewers but shall be stored in tanks or drums outside of any building until removed from the premises.
In addition to the previous restrictions of this paragraph, the following shall apply: There shall be no smoking or open flames in the areas used for fueling, servicing fuel systems for internal combustion engines, receiving or dispensing of flammable liquids. Conspicuous and legible signs prohibiting smoking shall be posted within sight of the customer being served. The motors of all equipment being fueled shall be shut off during the fueling operation.
Each service station shall be provided with at least one fire extinguisher having a minimum approved classification of 6 B, C, located so that an extinguisher, will be within 75 feet of each pump, dispenser, underground fill pipe opening, and lubrication or service room.
This paragraph shall apply to those plants or buildings which contain chemical operations such as oxidation, reduction, halogenation, hydrogenation, alkylation, polymerization, and other chemical processes but shall not apply to chemical plants, refineries or distilleries.
The location of each processing vessel shall be based upon its flammable liquid capacity.
Areas where Category 1 or unstable liquids are processed shall have explosion venting through one or more of the following methods:
Tank vehicle and tank car loading or unloading facilities shall be separated from aboveground tanks, warehouses, other plant buildings, or nearest line of adjoining property which may be built upon by a distance of 25 feet for Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), and 15 feet for Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) and Category 4 flammable liquids measured from the nearest position of any fill stem. Buildings for pumps or shelters for personnel may be a part of the facility. Operations of the facility shall comply with the appropriate portions of paragraph (f)(3) of this section.
Approved portable fire extinguishers of appropriate size, type, and number shall be provided.
Where the special hazards of operation or exposure indicate a need, the following fire control provision shall be provided.
An approved means for prompt notification of fire to those within the plant and any public fire department available shall be provided. It may be advisable to connect the plant system with the public system where public fire alarm system is available.
All plant fire protection facilities shall be adequately maintained and periodically inspected and tested to make sure they are always in satisfactory operating condition and that they will serve their purpose in time of emergency.
Maintenance and operating practices shall be in accordance with established procedures which will tend to control leakage and prevent the accidental escape of flammable liquids. Spills shall be cleaned up promptly.
Adequate aisles shall be maintained for unobstructed movement of personnel and so that fire protection equipment can be brought to bear on any part of the processing equipment.
Combustible waste material and residues in a building or operating area shall be kept to a minimum, stored in closed metal waste cans, and disposed of daily.
Ground area around buildings and operating areas shall be kept free of tall grass, weeds, trash, or other combustible materials.
Flammable liquids shall be stored in tanks, in containers, or in portable tanks. Tanks shall be installed in accordance with paragraph (b) of this section. Tanks for the storage of flammable liquids in tank farms and in locations other than process areas shall be located in accordance with paragraph (b)(2) (i) and (ii) of this section.
Wharves handling flammable liquids shall be in accordance with paragraph (f)(4) of this section.
Fired pressure vessels shall be constructed in accordance with the Code for Fired Pressure Vessels, Section I of the ASME Boiler and Pressure Vessel Code—1968.
Process units shall be located so that they are accessible from at least one side for the purpose of fire control.
Portable fire extinguishment and control equipment shall be provided in such quantities and types as are needed for the special hazards of operation and storage.
Water shall be available in volume and at adequate pressure to supply water hose streams, foam producing equipment, automatic sprinklers, or water spray systems as the need is indicated by the special hazards of operation and storage.
Special extinguishing equipment such as that utilizing foam, inert gas, or dry chemical shall be provided as the need is indicated by the special hazards of operation and storage.
This section applies to the handling, storage, and use of flammable liquids with a flashpoint at or below 199.4 °F (93 °C) unless otherwise noted. This section does not apply to:
32-1970;
36-1967; or
[39 FR 23502, June 27, 1974, as amended at 40 FR 3982, Jan. 27, 1975; 40 FR 23743, June 2, 1975; 43 FR 49746, Oct. 24, 1978; 43 FR 51759, Nov. 7, 1978; 47 FR 39164, Sept. 7, 1982; 51 FR 34560, Sept. 29, 1986; 53 FR 12121, Apr. 12, 1988; 55 FR 32015, Aug. 6, 1990; 61 FR 9237, Mar. 7, 1996; 70 FR 53929, Sept. 13, 2005; 77 FR 17765, Mar. 26, 2012]
Aerated powders shall mean any powdered material used as a coating material which shall be fluidized within a container by passing air uniformly from below. It is common practice to fluidize such materials to form a fluidized powder bed and then dip the part to be coated into the bed in a manner similar to that used in liquid dipping. Such beds are also used as sources for powder spray operations.
Any area in which dangerous quantities of flammable vapors or mists, or combustible residues, dusts, or deposits are present due to the operation of spraying processes.
A power-ventilated structure provided to enclose or accommodate a spraying operation to confine and limit the escape of spray, vapor, and residue, and to safely conduct or direct them to an exhaust system.
A spray booth equipped with a water washing system designed to minimize dusts or residues entering exhaust ducts and to permit the recovery of overspray finishing material.
A spray booth not equipped with a water washing system as described in subparagraph (4) of this paragraph. A dry spray booth may be equipped with (i) distribution or baffle plates to promote an even flow of air through the booth or cause the deposit of overspray before it enters the exhaust duct; or (ii) overspray dry filters to minimize dusts; or (iii) overspray dry filters to minimize dusts or residues entering exhaust ducts; or (iv) overspray dry filter rolls designed to minimize dusts or residues entering exhaust ducts; or (v) where dry powders are being sprayed, with powder collection systems so arranged in the exhaust to capture oversprayed material.
A container holding powder coating material which is aerated from below so as to form an air-supported expanded cloud of such material through which the preheated object to be coated is immersed and transported.
A container holding powder coating material which is aerated from below so as to form an air-supported expanded cloud of such material which is electrically charged with a charge opposite to the charge of the object to be coated; such object is transported, through the container immediately above the charged and aerated materials in order to be coated.
Shall mean approved and listed by a nationally recognized testing laboratory. Refer to § 1910.7 for definition of nationally recognized testing laboratory.
See “approved” in § 1910.107(a)(8).
Spray booths shall be substantially constructed of steel, securely and rigidly supported, or of concrete or masonry except that aluminum or other substantial noncombustible material may be used for intermittent or low volume spraying. Spray booths shall be designed to sweep air currents toward the exhaust outlet.
The interior surfaces of spray booths shall be smooth and continuous without edges and otherwise designed to prevent pocketing of residues and facilitate cleaning and washing without injury.
The floor surface of a spray booth and operator's working area, if combustible, shall be covered with noncombustible material of such character as to facilitate the safe cleaning and removal of residues.
Distribution or baffle plates, if installed to promote an even flow of air through the booth or cause the deposit of overspray before it enters the exhaust duct, shall be of noncombustible material and readily removable or accessible on both sides for cleaning. Such plates shall not be located in exhaust ducts.
In conventional dry type spray booths, overspray dry filters or filter rolls, if installed, shall conform to the following:
Each spray booth having a frontal area larger than 9 square feet shall have a metal deflector or curtain not less than 2 1/2 inches deep installed at the upper outer edge of the booth over the opening.
Where conveyors are arranged to carry work into or out of spray booths, the openings therefor shall be as small as practical.
Each spray booth shall be separated from other operations by not less than 3 feet, or by a greater distance, or by such partition or wall as to reduce the danger from juxtaposition of hazardous operations. See also paragraph (c)(1) of this section.
Spray booths shall be so installed that all portions are readily accessible for cleaning. A clear space of not less than 3 feet on all sides shall be kept free from storage or combustible construction.
When spraying areas are illuminated through glass panels or other transparent materials, only fixed lighting units shall be used as a source of illumination. Panels shall effectively isolate the spraying area from the area in which the lighting unit is located, and shall be of a noncombustible material of such a nature or so protected that breakage will be unlikely. Panels shall be so arranged that normal accumulations of residue on the exposed surface of the panel will not be raised to a dangerous temperature by radiation or conduction from the source of illumination.
All electrical equipment, open flames and other sources of ignition shall conform to the requirements of this paragraph, except as follows:
There shall be no open flame or spark producing equipment in any spraying area nor within 20 feet thereof, unless separated by a partition.
Space-heating appliances, steampipes, or hot surfaces shall not be located in a spraying area where deposits of combustible residues may readily accumulate.
Electrical wiring and equipment shall conform to the provisions of this paragraph and shall otherwise be in accordance with subpart S of this part.
Unless specifically approved for locations containing both deposits of readily ignitable residue and explosive vapors, there shall be no electrical equipment in any spraying area, whereon deposits of combustible residues may readily accumulate, except wiring in rigid conduit or in boxes or fittings containing no taps, splices, or terminal connections.
Electrical wiring and equipment not subject to deposits of combustible residues but located in a spraying area as herein defined shall be of explosion-proof type approved for Class I, group D locations and shall otherwise conform to the provisions of subpart S of this part, for Class I, Division 1, Hazardous Locations. Electrical wiring, motors, and other equipment outside of but within twenty (20) feet of any spraying area, and not separated therefrom by partitions, shall not produce sparks under normal operating conditions and shall otherwise conform to the provisions of subpart S of this part for Class I, Division 2 Hazardous Locations.
Electric lamps outside of, but within twenty (20) feet of any spraying area, and not separated therefrom by a partition, shall be totally enclosed to prevent the falling of hot particles and shall be protected from mechanical injury by suitable guards or by location.
Portable electric lamps shall not be used in any spraying area during spraying operations. Portable electric lamps, if used during cleaning or repairing operations, shall be of the type approved for hazardous Class I locations.
Ventilating and exhaust systems shall be in accordance with the Standard for Blower and Exhaust Systems for Vapor Removal, NFPA No. 91-1961, which is incorporated by reference as specified in § 1910.6, where applicable and shall also conform to the provisions of this section.
All spraying areas shall be provided with mechanical ventilation adequate to remove flammable vapors, mists, or powders to a safe location and to confine and control combustible residues so that life is not endangered. Mechanical ventilation shall be kept in operation at all times while spraying operations are being conducted and for a sufficient time thereafter to allow vapors from drying coated articles and drying finishing material residue to be exhausted.
Each spray booth shall have an independent exhaust duct system discharging to the exterior of the building, except that multiple cabinet spray booths in which identical spray finishing material is used with a combined frontal area of not more than 18 square feet may have a common exhaust. If more than one fan serves one booth, all fans shall be so interconnected that one fan cannot operate without all fans being operated.
The fan-rotating element shall be nonferrous or nonsparking or the casing shall consist of or be lined with such material. There shall be ample clearance between the fan-rotating element and the fan casing to avoid a fire by friction, necessary allowance being made for ordinary expansion and loading to prevent contact between moving parts and the duct or fan housing. Fan blades shall be mounted on a shaft sufficiently heavy to maintain perfect alignment even when the blades of the fan are heavily loaded, the shaft preferably to have bearings outside the duct and booth. All bearings shall be of the self-lubricating type, or lubricated from the outside duct.
Electric motors driving exhaust fans shall not be placed inside booths or ducts. See also paragraph (c) of this section.
Belts shall not enter the duct or booth unless the belt and pulley within the duct or booth are thoroughly enclosed.
Exhaust ducts shall be constructed of steel and shall be substantially supported. Exhaust ducts without dampers are preferred; however, if dampers are installed, they shall be maintained so that they will be in a full open position at all times the ventilating system is in operation.
| ( a ) 28-gage sheet metal on 1 ⁄ 4 -inch asbestos mill board | 12 inches. |
|---|---|
| ( b ) 28-gage sheet metal on 1 ⁄ 8 -inch asbestos mill board spaced out 1 inch on noncombustible spacers | 9 inches. |
| ( c ) 22-gage sheet metal on 1-inch rockwool batts reinforced with wire mesh or the equivalent | 3 inches. |
| ( d ) Where ducts are protected with an approved automatic sprinkler system, properly maintained, the clearance required in subdivision (i) of this subparagraph may be reduced to 6 inches |
Unless the spray booth exhaust duct terminal is from a water-wash spray booth, the terminal discharge point shall be not less than 6 feet from any combustible exterior wall or roof nor discharge in the direction of any combustible construction or unprotected opening in any noncombustible exterior wall within 25 feet.
Air exhaust from spray operations shall not be directed so that it will contaminate makeup air being introduced into the spraying area or other ventilating intakes, nor directed so as to create a nuisance. Air exhausted from spray operations shall not be recirculated.
When necessary to facilitate cleaning, exhaust ducts shall be provided with an ample number of access doors.
Air intake openings to rooms containing spray finishing operations shall be adequate for the efficient operation of exhaust fans and shall be so located as to minimize the creation of dead air pockets.
Freshly sprayed articles shall be dried only in spaces provided with adequate ventilation to prevent the formation of explosive vapors. In the event adequate and reliable ventilation is not provided such drying spaces shall be considered a spraying area. See also paragraph (j) of this section.
The storage of flammable liquids or liquids with a flashpoint greater than 199.4 °F (93 °C) in connection with spraying operations shall conform to the requirements of § 1910.106, where applicable.
The quantity of flammable liquids or liquids with a flashpoint greater than 199.4 °F (93 °C) kept in the vicinity of spraying operations shall be the minimum required for operations and should ordinarily not exceed a supply for 1 day or one shift. Bulk storage of portable containers of flammable liquids or liquids with a flashpoint greater than 199.4 °F (93 °C) shall be in a separate, constructed building detached from other important buildings or cut off in a standard manner.
Original closed containers, approved portable tanks, approved safety cans or a properly arranged system of piping shall be used for bringing flammable liquids or liquids with a flashpoint greater than 199.4 °F (93 °C) into spray finishing room. Open or glass containers shall not be used.
Except as provided in paragraph (e)(5) of this section the withdrawal of flammable liquids and liquids with a flashpoint greater than 199.4 °F (93 °C) from containers having a capacity of greater than 60 gallons shall be by approved pumps. The withdrawal of flammable liquids or liquids with a flashpoint greater than 199.4 °F (93 °C) from containers and the filling of containers, including portable mixing tanks, shall be done only in a suitable mixing room or in a spraying area when the ventilating system is in operation. Adequate precautions shall be taken to protect against liquid spillage and sources of ignition.
Containers supplying spray nozzles shall be of closed type or provided with metal covers kept closed. Containers not resting on floors shall be on metal supports or suspended by wire cables. Containers supplying spray nozzles by gravity flow shall not exceed 10 gallons capacity. Original shipping containers shall not be subject to air pressure for supplying spray nozzles. Containers under air pressure supplying spray nozzles shall be of limited capacity, not exceeding that necessary for 1 day's operation; shall be designed and approved for such use; shall be provided with a visible pressure gage; and shall be provided with a relief valve set to operate in conformance with the requirements of the Code for Unfired Pressure Vessels, Section VIII of the ASME Boiler and Pressure Vessel Code—1968, which is incorporated by reference as specified in § 1910.6. Containers under air pressure supplying spray nozzles, air-storage tanks and coolers shall conform to the standards of the Code for Unfired Pressure Vessels, Section VIII of the ASME Boiler and Pressure Vessel Code—1968 for construction, tests, and maintenance.
Electrically powered spray liquid heaters shall be approved and listed for the specific location in which used (see paragraph (c) of this section). Heaters shall not be located in spray booths nor other locations subject to the accumulation of deposits or combustible residue. If an electric motor is used, see paragraph (c) of this section.
If flammable liquids or liquids with a flashpoint greater than 199.4 °F (93 °C) are supplied to spray nozzles by positive displacement pumps, the pump discharge line shall be provided with an approved relief valve discharging to a pump suction or a safe detached location, or a device provided to stop the prime mover if the discharge pressure exceeds the safe operating pressure of the system.
Whenever flammable liquids or liquids with a flashpoint greater than 199.4 °F (93 °C) are transferred from one container to another, both containers shall be effectively bonded and grounded to prevent discharge sparks of static electricity.
In sprinklered buildings, the automatic sprinkler system in rooms containing spray finishing operations shall conform to the requirements of § 1910.159. In unsprinklered buildings where sprinklers are installed only to protect spraying areas, the installation shall conform to such standards insofar as they are applicable. Sprinkler heads shall be located so as to provide water distribution throughout the entire booth.
Automatic sprinklers protecting each spray booth (together with its connecting exhaust) shall be under an accessibly located separate outside stem and yoke (OS&Y) subcontrol valve.
Sprinklers protecting spraying areas shall be kept as free from deposits as practical by cleaning daily if necessary. (See also paragraph (g) of this section.)
An adequate supply of suitable portable fire extinguishers shall be installed near all spraying areas.
Spraying shall not be conducted outside of predetermined spraying areas.
All spraying areas shall be kept as free from the accumulation of deposits of combustible residues as practical, with cleaning conducted daily if necessary. Scrapers, spuds, or other such tools used for cleaning purposes shall be of nonsparking material.
Residue scrapings and debris contaminated with residue shall be immediately removed from the premises and properly disposed of. Approved metal waste cans shall be provided wherever rags or waste are impregnated with finishing material and all such rags or waste deposited therein immediately after use. The contents of waste cans shall be properly disposed of at least once daily or at the end of each shift.
Spray finishing employees' clothing shall not be left on the premises overnight unless kept in metal lockers.
The use of solvents for cleaning operations shall be restricted to those having flashpoints not less than 100 °F.; however, for cleaning spray nozzles and auxiliary equipment, solvents having flashpoints not less than those normally used in spray operations may be used. Such cleaning shall be conducted inside spray booths and ventilating equipment operated during cleaning.
Spray booths shall not be alternately used for different types of coating materials, where the combination of the materials may be conducive to spontaneous ignition, unless all deposits of the first used material are removed from the booth and exhaust ducts prior to spraying with the second used material.
“No smoking” signs in large letters on contrasting color background shall be conspicuously posted at all spraying areas and paint storage rooms.
Where installation and use of electrostatic spraying equipment is used, such installation and use shall conform to all other paragraphs of this section, and shall also conform to the requirements of this paragraph.
Electrostatic apparatus and devices used in connection with coating operations shall be of approved types.
Transformers, power packs, control apparatus, and all other electrical portions of the equipment, with the exception of high-voltage grids, electrodes, and electrostatic atomizing heads and their connections, shall be located outside of the spraying area, or shall otherwise conform to the requirements of paragraph (c) of this section.
Electrodes and electrostatic atomizing heads shall be adequately supported in permanent locations and shall be effectively insulated from the ground. Electrodes and electrostatic atomizing heads which are permanently attached to their bases, supports, or reciprocators, shall be deemed to comply with this section. Insulators shall be nonporous and noncombustible.
High-voltage leads to electrodes shall be properly insulated and protected from mechanical injury or exposure to destructive chemicals. Electrostatic atomizing heads shall be effectively and permanently supported on suitable insulators and shall be effectively guarded against accidental contact or grounding. An automatic means shall be provided for grounding the electrode system when it is electrically deenergized for any reason. All insulators shall be kept clean and dry.
A safe distance shall be maintained between goods being painted and electrodes or electrostatic atomizing heads or conductors of at least twice the sparking distance. A suitable sign indicating this safe distance shall be conspicuously posted near the assembly.
Goods being painted using this process are to be supported on conveyors. The conveyors shall be so arranged as to maintain safe distances between the goods and the electrodes or electrostatic atomizing heads at all times. Any irregularly shaped or other goods subject to possible swinging or movement shall be rigidly supported to prevent such swinging or movement which would reduce the clearance to less than that specified in paragraph (h)(6) of this section.
This process is not acceptable where goods being coated are manipulated by hand. When finishing materials are applied by electrostatic equipment which is manipulated by hand, see paragraph (i) of this section for applicable requirements.
Electrostatic apparatus shall be equipped with automatic controls which will operate without time delay to disconnect the power supply to the high voltage transformer and to signal the operator under any of the following conditions:
Adequate booths, fencing, railings, or guards shall be so placed about the equipment that they, either by their location or character or both, assure that a safe isolation of the process is maintained from plant storage or personnel. Such railings, fencing, and guards shall be of conducting material, adequately grounded.
Where electrostatic atomization is used the spraying area shall be so ventilated as to insure safe conditions from a fire and health standpoint.
All areas used for spraying, including the interior of the booth, shall be protected by automatic sprinklers where this protection is available. Where this protection is not available, other approved automatic extinguishing equipment shall be provided.
This paragraph shall apply to any equipment using electrostatically charged elements for the atomization and/or, precipitation of materials for coatings on articles, or for other similar purposes in which the atomizing device is hand held and manipulated during the spraying operation.
Electrostatic hand spraying equipment shall conform with the other provisions of this section.
Electrostatic hand spray apparatus and devices used in connection with coating operations shall be of approved types. The high voltage circuits shall be designed so as to not produce a spark of sufficient intensity to ignite any vapor-air mixtures nor result in appreciable shock hazard upon coming in contact with a grounded object under all normal operating conditions. The electrostatically charged exposed elements of the handgun shall be capable of being energized only by a switch which also controls the coating material supply.
Transformers, powerpacks, control apparatus, and all other electrical portions of the equipment, with the exception of the handgun itself and its connections to the power supply shall be located outside of the spraying area or shall otherwise conform to the requirements of paragraph (c) of this section.
The handle of the spraying gun shall be electrically connected to ground by a metallic connection and to be so constructed that the operator in normal operating position is in intimate electrical contact with the grounded handle.
All electrically conductive objects in the spraying area shall be adequately grounded. This requirement shall apply to paint containers, wash cans, and any other objects or devices in the area. The equipment shall carry a prominent permanently installed warning regarding the necessity for this grounding feature.
Objects being painted or coated shall be maintained in metallic contact with the conveyor or other grounded support. Hooks shall be regularly cleaned to insure this contact and areas of contact shall be sharp points or knife edges where possible. Points of support of the object shall be concealed from random spray where feasible and where the objects being sprayed are supported from a conveyor, the point of attachment to the conveyor shall be so located as to not collect spray material during normal operation.
The electrical equipment shall be so interlocked with the ventilation of the spraying area that the equipment cannot be operated unless the ventilation fans are in operation.
The spraying operation shall take place within a spray area which is adequately ventilated to remove solvent vapors released from the operation.
Drying, curing, or fusion apparatus in connection with spray application of flammable and combustible finishes shall conform to the Standard for Ovens and Furnaces, NFPA 86A-1969, which is incorporated by reference as specified in § 1910.6, where applicable and shall also conform with the following requirements of this paragraph.
Spray booths, rooms, or other enclosures used for spraying operations shall not alternately be used for the purpose of drying by any arrangement which will cause a material increase in the surface temperature of the spray booth, room, or enclosure.
Except as specifically provided in paragraph (j)(4) of this section, drying, curing, or fusion units utilizing a heating system having open flames or which may produce sparks shall not be installed in a spraying area, but may be installed adjacent thereto when equipped with an interlocked ventilating system arranged to:
Automobile refinishing spray booths or enclosures, otherwise installed and maintained in full conformity with this section, may alternately be used for drying with portable electrical infrared drying apparatus when conforming with the following:
Automobile undercoating spray operations in garages, conducted in areas having adequate natural or mechanical ventilation, are exempt from the requirements pertaining to spray finishing operations, when using undercoating materials not more hazardous than kerosene (as listed by Underwriters' Laboratories in respect to fire hazard rating 30-40) or undercoating materials using only solvents listed as having a flash point in excess of 100 °F. Undercoating spray operations not conforming to these provisions are subject to all requirements of this section pertaining to spray finishing operations.
Electrical equipment and other sources of ignition shall conform to the requirements of paragraphs (c)(1) (i)-
The provisions of paragraph (h) of this section and other subparagraphs of this paragraph shall apply to fixed electrostatic equipment, except that electrical equipment not covered therein shall conform to paragraph (l)(1) of this section.
The provisions of paragraph (i) of this section and other subparagraphs of this paragraph, shall apply to electrostatic handguns when used in powder coating, except that electrical equipment not covered therein shall conform to paragraph (l)(1) of this section.
All spraying operations involving the use of organic peroxides and other dual component coatings shall be conducted in approved sprinklered spray booths meeting the requirements of this section.
Smoking shall be prohibited and “No Smoking” signs shall be prominently displayed and only nonsparking tools shall be used in any area where organic peroxides are stored, mixed or applied.
This section applies to flammable and combustible finishing materials when applied as a spray by compressed air, “airless” or “hydraulic atomization,” steam, electrostatic methods, or by any other means in continuous or intermittent processes. The section also covers the application of combustible powders by powder spray guns, electrostatic powder spray guns, fluidized beds, or electrostatic fluidized beds. The section does not apply to outdoor spray application of buildings, tanks, or other similar structures, nor to small portable spraying apparatus not used repeatedly in the same location.
[39 FR 23502, June 27, 1974, as amended at 45 FR 60704, Sept. 12, 1980; 49 FR 5322, Feb. 10, 1984; 53 FR 12121, Apr. 12, 1988; 61 FR 9237, Mar. 7, 1996; 72 FR 71069, Dec. 14, 2007; 77 FR 17776, Mar. 26, 2012]
Blasting agent—any material or mixture, consisting of a fuel and oxidizer, intended for blasting, not otherwise classified as an explosive and in which none of the ingredients are classified as an explosive, provided that the finished product, as mixed and packaged for use or shipment, cannot be detonated by means of a No. 8 test blasting cap when unconfined.
Explosive-actuated power device—any tool or special mechanized device which is actuated by explosives, but not including propellant-actuated power devices. Examples of explosive-actuated power devices are jet tappers and jet perforators.
Explosive—any chemical compound, mixture, or device, the primary or common purpose of which is to function by explosion, i.e., with substantially instantaneous release of gas and heat, unless such compound, mixture, or device is otherwise specifically classified by the U.S. Department of Transportation; see 49 CFR chapter I. The term “explosives” shall include all material which is classified as Class A, Class B, and Class C explosives by the U.S. Department of Transportation, and includes, but is not limited to dynamite, black powder, pellet powders, initiating explosives, blasting caps, electric blasting caps, safety fuse, fuse lighters, fuse igniters, squibs, cordeau detonant fuse, instantaneous fuse, igniter cord, igniters, small arms ammunition, small arms ammunition primers, smokeless propellant, cartridges for propellant-actuated power devices, and cartridges for industrial guns. Commercial explosives are those explosives which are intended to be used in commercial or industrial operations.
Possessing, detonating, or otherwise maximum hazard; such as dynamite, nitroglycerin, picric acid, lead azide, fulminate of mercury, black powder, blasting caps, and detonating primers.
Possessing flammable hazard, such as propellant explosives (including some smokeless propellants), photographic flash powders, and some special fireworks.
Includes certain types of manufactured articles which contain Class A or Class B explosives, or both, as components but in restricted quantities.
Explosives which are forbidden or not acceptable for transportation by common carriers by rail freight, rail express, highway, or water in accordance with the regulations of the U.S. Department of Transportation, 49 CFR chapter I.
Highway—any public street, public alley, or public road.
Magazine—any building or structure, other than an explosives manufacturing building, used for the storage of explosives.
Motor vehicle—any self-propelled vehicle, truck, tractor, semitrailer, or truck-full trailers used for the transportation of freight over public highways.
Propellant-actuated power devices—any tool or special mechanized device or gas generator system which is actuated by a smokeless propellant or which releases and directs work through a smokeless propellant charge.
Pyrotechnics—any combustible or explosive compositions or manufactured articles designed and prepared for the purpose of producing audible or visible effects which are commonly referred to as fireworks.
Semiconductive hose—a hose with an electrical resistance high enough to limit flow of stray electric currents to safe levels, yet not so high as to prevent drainage of static electric charges to ground; hose of not more than 2 megohms resistance over its entire length and of not less than 5,000 ohms per foot meets the requirement.
Small arms ammunition—any shotgun, rifle, pistol, or revolver cartridge, and cartridges for propellant-actuated power devices and industrial guns. Military-type ammunition containing explosive-bursting charges, incendiary, tracer, spotting, or pyrotechnic projectiles is excluded from this definition.
Small arms ammunition primers—small percussion-sensitive explosive charges, encased in a cup, used to ignite propellant powder.
Smokeless propellants—solid propellants, commonly called smokeless powders in the trade, used in small arms ammunition, cannon, rockets, propellant-actuated power devices, etc.
Special industrial explosives devices—explosive-actuated power devices and propellant-actuated power devices.
Special industrial explosives materials—shaped materials and sheet forms and various other extrusions, pellets, and packages of high explosives, which include dynamite, trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), hexahydro-1,3,5-trinitro-s-triazine (RDX), and other similar compounds used for high-energy-rate forming, expanding, and shaping in metal fabrication, and for dismemberment and quick reduction of scrap metal.
These comprise a wide variety of materials used for blasting. They all contain substantial proportions of water and high proportions of ammonium nitrate, some of which is in solution in the water. Two broad classes of water gels are (i) those which are sensitized by a material classed as an explosive, such as TNT or smokeless powder, (ii) those which contain no ingredient classified as an explosive; these are sensitized with metals such as aluminum or with other fuels. Water gels may be premixed at an explosives plant or mixed at the site immediately before delivery into the borehole.
Regulations of the Department of Transportation published in 49 CFR chapter I.
No person shall store, handle, or transport explosives or blasting agents when such storage, handling, and transportation of explosives or blasting agents constitutes an undue hazard to life.
| Explosives | Distances in feet when storage is barricaded: Separation of magazines | |
|---|---|---|
| Pounds over | Pounds not over | |
| 2 | 5 | 6 |
| 5 | 10 | 8 |
| 10 | 20 | 10 |
| 20 | 30 | 11 |
| 30 | 40 | 12 |
| 40 | 50 | 14 |
| 50 | 75 | 15 |
| 75 | 100 | 16 |
| 100 | 125 | 18 |
| 125 | 150 | 19 |
| 150 | 200 | 21 |
| 200 | 250 | 23 |
| 250 | 300 | 24 |
| 300 | 400 | 27 |
| 400 | 500 | 29 |
| 500 | 600 | 31 |
| 600 | 700 | 32 |
| 700 | 800 | 33 |
| 800 | 900 | 35 |
| 900 | 1,000 | 36 |
| 1,000 | 1,200 | 39 |
| 1,200 | 1,400 | 41 |
| 1,400 | 1,600 | 43 |
| 1,600 | 1,800 | 44 |
| 1,800 | 2,000 | 45 |
| 2,000 | 2,500 | 49 |
| 2,500 | 3,000 | 52 |
| 3,000 | 4,000 | 58 |
| 4,000 | 5,000 | 61 |
| 5,000 | 6,000 | 65 |
| 6,000 | 7,000 | 68 |
| 7,000 | 8,000 | 72 |
| 8,000 | 9,000 | 75 |
| 9,000 | 10,000 | 78 |
| 10,000 | 12,000 | 82 |
| 12,000 | 14,000 | 87 |
| 14,000 | 16,000 | 90 |
| 16,000 | 18,000 | 94 |
| 18,000 | 20,000 | 98 |
| 20,000 | 25,000 | 105 |
| 25,000 | 30,000 | 112 |
| 30,000 | 35,000 | 119 |
| 35,000 | 40,000 | 124 |
| 40,000 | 45,000 | 129 |
| 45,000 | 50,000 | 135 |
| 50,000 | 55,000 | 140 |
| 55,000 | 60,000 | 145 |
| 60,000 | 65,000 | 150 |
| 65,000 | 70,000 | 155 |
| 70,000 | 75,000 | 160 |
| 75,000 | 80,000 | 165 |
| 80,000 | 85,000 | 170 |
| 85,000 | 90,000 | 175 |
| 90,000 | 95,000 | 180 |
| 95,000 | 100,000 | 185 |
| 100,000 | 110,000 | 195 |
| 110,000 | 120,000 | 205 |
| 120,000 | 130,000 | 215 |
| 130,000 | 140,000 | 225 |
| 140,000 | 150,000 | 235 |
| 150,000 | 160,000 | 245 |
| 160,000 | 170,000 | 255 |
| 170,000 | 180,000 | 265 |
| 180,000 | 190,000 | 275 |
| 190,000 | 200,000 | 285 |
| 200,000 | 210,000 | 295 |
| 210,000 | 230,000 | 315 |
| 230,000 | 250,000 | 335 |
| 250,000 | 275,000 | 360 |
| 275,000 | 300,000 | 385 |
| 1 “Natural barricade” means natural features of the ground, such as hills, or timber of sufficient density that the surrounding exposures which require protection cannot be seen from the magazine when the trees are bare of leaves. | ||
| 2 “Artificial barricade” means an artificial mound or revetted wall of earth of a minimum thickness of three feet. | ||
| 3 “Barricaded” means that a building containing explosives is effectually screened from a magazine, building, railway, or highway, either by a natural barricade, or by an artificial barricade of such height that a straight line from the top of any sidewall of the building containing explosives to the eave line of any magazine, or building, or to a point 12 feet above the center of a railway or highway, will pass through such intervening natural or artificial barricade. | ||
| 4 When two or more storage magazines are located on the same property, each magazine must comply with the minimum distances specified from inhabited buildings, railways, and highways, and in addition, they should be separated from each other by not less than the distances shown for “Separation of Magazines,” except that the quantity of explosives contained in cap magazines shall govern in regard to the spacing of said cap magazines from magazines containing other explosives. If any two or more magazines are separated from each other by less than the specified “Separation of Magazines” distances, then such two or more magazines, as a group, must be considered as one magazine, and the total quantity of explosives stored in such group must be treated as if stored in a single magazine located on the site of any magazine of the group, and must comply with the minimum of distances specified from other magazines, inhabited buildings, railways, and highways. | ||
| 5 This table applies only to the permanent storage of commercial explosives. It is not applicable to transportation of explosives, or any handling or temporary storage necessary or incident thereto. It is not intended to apply to bombs, projectiles, or other heavily encased explosives. |
| Commodity | Type of marking or placard |
|---|---|
| Explosives, Class A, any quantity or a combination of Class A and Class B explosives | Explosives A (Red letters on white background). |
| Explosives, Class B, and quantity | Explosives B (Red letters on white background). |
| Oxidizing material (blasting agents, ammonium nitrate, etc.), 1,000 pounds or more gross weight | Oxidizers (Yellow letters on black background). |
Before a blast is fired, the employer shall require that a loud warning signal be given by the person in charge, who has made certain that all surplus explosives are in a safe place, all persons and vehicles are at a safe distance or under sufficient cover, and that an adequate warning has been given.
Except in an emergency and with permission of the local authority, no person shall have or keep explosives in a railway car unless said car and contents and methods of loading are in accordance with the U.S. Department of Transportation Regulations for the Transportation of Explosives, 49 CFR chapter I.
No person shall deliver any explosive to any carrier unless such explosive conforms in all respects, including marking and packing, to the U.S. Department of Transportation Regulations for the Transportation of Explosives.
Every railway car containing explosives which has reached its designation, or is stopped in transit so as no longer to be in interstate commerce, shall have attached to both sides and ends of the car, cards with the words “Explosives—Handle Carefully—Keep Fire Away” in red letters at least 1 1/2 inches high on a white background.
Any explosives at a railway facility, truck terminal, pier, wharf harbor facility, or airport terminal whether for delivery to a consignee, or forwarded to some other destination shall be kept in a safe place, isolated as far as practicable and in such manner that they can be easily and quickly removed.
Explosives shall not be delivered to or received from any railway station, truck terminal, pier, wharf, harbor facility, or airport terminal between the hours of sunset and sunrise.
Unless otherwise set forth in this paragraph, blasting agents, excluding water gels, shall be transported, stored, and used in the same manner as explosives. Water gels are covered in paragraph (h) of this section.
| Donor weight | Minimum separation distance of receptor when barricaded 2 (ft.) | Minimum thickness of artificial barricades 5 (in.) | ||
|---|---|---|---|---|
| Pounds over | Pounds not over | Ammonium nitrate 3 | Blasting agent 4 | |
| 100 | 3 | 11 | 12 | |
| 100 | 300 | 4 | 14 | 12 |
| 300 | 600 | 5 | 18 | 12 |
| 600 | 1,000 | 6 | 22 | 12 |
| 1,000 | 1,600 | 7 | 25 | 12 |
| 1,600 | 2,000 | 8 | 29 | 12 |
| 2,000 | 3,000 | 9 | 32 | 15 |
| 3,000 | 4,000 | 10 | 36 | 15 |
| 4,000 | 6,000 | 11 | 40 | 15 |
| 6,000 | 8,000 | 12 | 43 | 20 |
| 8,000 | 10,000 | 13 | 47 | 20 |
| 10,000 | 12,000 | 14 | 50 | 20 |
| 12,000 | 16,000 | 15 | 54 | 25 |
| 16,000 | 20,000 | 16 | 58 | 25 |
| 20,000 | 25,000 | 18 | 65 | 25 |
| 25,000 | 30,000 | 19 | 68 | 30 |
| 30,000 | 35,000 | 20 | 72 | 30 |
| 35,000 | 40,000 | 21 | 76 | 30 |
| 40,000 | 45,000 | 22 | 79 | 35 |
| 45,000 | 50,000 | 23 | 83 | 35 |
| 50,000 | 55,000 | 24 | 86 | 35 |
| 55,000 | 60,000 | 25 | 90 | 35 |
| 60,000 | 70,000 | 26 | 94 | 40 |
| 70,000 | 80,000 | 28 | 101 | 40 |
| 80,000 | 90,000 | 30 | 108 | 40 |
| 90,000 | 100,000 | 32 | 115 | 40 |
| 100,000 | 120,000 | 34 | 122 | 50 |
| 120,000 | 140,000 | 37 | 133 | 50 |
| 140,000 | 160,000 | 40 | 144 | 50 |
| 160,000 | 180,000 | 44 | 158 | 50 |
| 180,000 | 200,000 | 48 | 173 | 50 |
| 200,000 | 220,000 | 52 | 187 | 60 |
| 220,000 | 250,000 | 56 | 202 | 60 |
| 250,000 | 275,000 | 60 | 216 | 60 |
| 275,000 | 300,000 | 64 | 230 | 60 |
| 1 These distances apply to the separation of stores only. Table H-21 shall be used in determining separation distances from inhabited buildings, passenger railways, and public highways. | ||||
| 2 When the ammonium nitrate and/or blasting agent is not barricaded, the distances shown in the table shall be multiplied by six. These distances allow for the possibility of high velocity metal fragments from mixers, hoppers, truck bodies, sheet metal structures, metal container, and the like which may enclose the “donor”. Where storage is in bullet-resistant magazines recommended for explosives or where the storage is protected by a bullet-resistant wall, distances, and barricade thicknesses in excess of those prescribed in Table H-21 are not required. | ||||
| 3 The distances in the table apply to ammonium nitrate that passes the insensitivity test prescribed in the definition of ammonium nitrate fertilizer promulgated by the National Plant Food Institute*; and ammonium nitrate failing to pass said test shall be stored at separation distances determined by competent persons. (*Definition and Test Procedures for Ammonium Nitrate Fertilizer, National Plant Food Institute, November 1964.) | ||||
| 4 These distances apply to nitro-carbo-nitrates and blasting agents which pass the insensitivity test prescribed in the U.S. Department of Transportation (DOT) regulations. | ||||
| 5 Earth, or sand dikes, or enclosures filled with the prescribed minimum thickness of earth or sand are acceptable artificial barricades. Natural barricades, such as hills or timber of sufficient density that the surrounding exposures which require protection cannot be seen from the “donor” when the trees are bare of leaves, are also acceptable. | ||||
| 6 When the ammonium nitrate must be counted in determining the distances to be maintained from inhabited buildings, passenger railways and public highways, it may be counted at one-half its actual weight because its blast effect is lower. | ||||
| Note 7: Guide to use of table of recommended separation distances of ammonium nitrate and blasting agents from explosives or blasting agents. | ||||
| (a) Sketch location of all potential donor and acceptor materials together with the maximum mass of material to be allowed in that vicinity. (Potential donors are high explosives, blasting agents, and combination of masses of detonating materials. Potential acceptors are high explosives, blasting agents, and ammonium nitrate.) | ||||
| (b) Consider separately each donor mass in combination with each acceptor mass. If the masses are closer than table allowance (distances measured between nearest edges), the combination of masses becomes a new potential donor of weight equal to the total mass. When individual masses are considered as donors, distances to potential acceptors shall be measured between edges. When combined masses within propagating distance of each other are considered as a donor, the appropriate distance to the edge of potential acceptors shall be computed as a weighted distance from the combined masses. | ||||
| Calculation of weighted distance from combined masses: | ||||
| Let M 2 , M 3 . . . M n be donor masses to be combined. | ||||
| M 1 is a potential acceptor mass. | ||||
| D 1 2 is distance from M 1 to M 2 (edge to edge). | ||||
| D 1 3 is distance from M 1 to M 3 (edge to edge), etc. | ||||
| To find weighted distance [ D 1 ( 2 , 3 . . . n )] from combined masses to M 1 , add the products of the individual masses and distances and divide the total by the sum of the masses thus: | ||||
| D 1 ( 2 , 3 . . . n )= M 2 × D 12 + M 3 × D 12 . . . + M n × D 12 M 2 + M 3 . . . + M n | ||||
| Propagation is possible if either an individual donor mass is less than the tabulated distance from an acceptor or a combined mass is less than the weighted distance from an acceptor. | ||||
| (c) In determining the distances separating highways, railroads, and inhabited buildings from potential explosions (as prescribed in Table H-21), the sum of all masses which may propagate (i.e., lie at distances less than prescribed in the Table) from either individual or combined donor masses are included. However, when the ammonium nitrate must be included, only 50 percent of its weight shall be used because of its reduced blast effects. In applying Table H-21 to distances from highways, railroads, and inhabited buildings, distances are measured from the nearest edge of potentially explodable material as prescribed in Table H-21, Note 5. | ||||
| (d) When all or part of a potential acceptor comprises Explosives Class A as defined in DOT regulations, storage in bullet-resistant magazines is required. Safe distances to stores in bullet-resistant magazines may be obtained from the intermagazine distances prescribed in Table H-21. | ||||
| (e) Barricades must not have line-of-sight openings between potential donors and acceptors which permit blast or missiles to move directly between masses. | ||||
| (f) Good housekeeping practices shall be maintained around any bin containing ammonium nitrate or blasting agent. This includes keeping weeds and other combustible materials cleared within 25 feet of such bin. Accumulation of spilled product on the ground shall be prevented. |
Persons using blasting agents shall comply with all of the applicable provisions of paragraph (e) of this section.
Unless otherwise set forth in this paragraph, water gels shall be transported, stored and used in the same manner as explosives or blasting agents in accordance with the classification of the product.
This paragraph does not apply to in-process storage and intraplant transportation during manufacture of small arms ammunition, small arms primers, and smokeless propellants.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49747, Oct. 24, 1978; 45 FR 60704, Sept. 12, 1980; 53 FR 12122, Apr. 12, 1988; 57 FR 6403, Feb. 24, 1992; 58 FR 35309, June 30, 1993; 61 FR 9237, Mar. 7, 1996; 63 FR 33466, June 18, 1998]
As used in this section:
container—A container constructed in accordance with the requirements of paragraph (b)(3)(iii) of this section.
container—A container constructed in accordance with the requirements of paragraph (b)(3)(i) of this section.
container—A container constructed in accordance with the applicable requirements of 49 CFR chapter 1.
Specifications—regulations of the Department of Transportation published in 49 CFR chapter I.
cylinders—cylinders meeting the requirements of 49 CFR chapter I.
| Water capacity per container | Minimum distances | ||
|---|---|---|---|
| Containers | Between aboveground containers | ||
| Underground | Aboveground | ||
| Less than 125 gals. 1 | 10 feet | None | None. |
| 125 to 250 gals | 10 feet | 10 feet | None. |
| 251 to 500 gals | 10 feet | 10 feet | 3 feet. |
| 501 to 2,000 gals | 25 feet 2 | 25 feet 2 | 3 feet. |
| 2,001 to 30,000 gals | 50 feet | 50 feet | 5 feet. |
| 30,001 to 70,000 gals | 50 feet | 75 feet. 3 | |
| 70,001 to 90,000 gals | 50 feet | 100 feet. 3 | |
| 1 If the aggregate water capacity of a multi-container installation at a consumer site is 501 gallons or greater, the minimum distance shall comply with the appropriate portion of this table, applying the aggregate capacity rather than the capacity per container. If more than one installation is made, each installation shall be separated from another installation by at least 25 feet. Do not apply the MINIMUM DISTANCES BETWEEN ABOVE-GROUND CONTAINERS to such installations. | |||
| 2 The above distance requirements may be reduced to not less than 10 feet for a single container of 1,200 gallons water capacity or less, providing such a container is at least 25 feet from any other LP-Gas container of more than 125 gallons water capacity. | |||
| 3 1 ⁄ 4 of sum of diameters of adjacent containers. |
and all liquid piping shall be suitable for a working pressure of at least 250 p.s.i.g. Pipe shall be at least Schedule 80 if joints are threaded or threaded and back welded. At least Schedule 40 (ASTM A-53-69 Grade B Electric Resistance Welded and Electric Flash Welded Pipe or equal) shall be used if joints are welded, or welded and flanged.
Aluminum alloy tubing shall be protected against external corrosion when it is in contact with dissimilar metals other than galvanized steel, or its location is subject to repeated wetting by liquids such as water (except rainwater), detergents, sewage, or leakage from other piping, or it passes through flooring, plaster, masonry, or insulation. Galvanized sheet steel or pipe, galvanized inside and out, may be considered suitable protection. The maximum outside diameter for aluminum alloy tubing shall be three-fourths inch and shall not be used for pressures exceeding 20 p.s.i.g. Aluminum alloy tubing shall not be installed within 6 inches of the ground.
| Standard size (inches) | Nominal outside diameter (inches) | Nominal wall thickness (inches) | |
|---|---|---|---|
| Type K | Type L | ||
| 1 ⁄ 4 | 0.375 | 0.035 | 0.030 |
| 3 ⁄ 8 | 0.500 | 0.049 | 0.035 |
| 1 ⁄ 2 | 0.625 | 0.049 | 0.040 |
| 5 ⁄ 8 | 0.750 | 0.049 | 0.042 |
| 3 ⁄ 4 | 0.875 | 0.065 | 0.045 |
| 1 | 1.125 | 0.065 | 0.050 |
| 1 1 ⁄ 4 | 1.375 | 0.065 | 0.055 |
| 1 1 ⁄ 2 | 1.625 | 0.072 | 0.060 |
| 2 | 2.125 | 0.083 | 0.070 |
| 1 Based on data in Specification for Seamless Copper Water Tube, ANSI H23.1-1970 (ASTM B-88-69). | |||
| Note: The standard size by which tube is designated is 1 ⁄ 8 inch smaller than its nominal outside diameter. |
| Outside diameter (inches) | Nominal wall thickness (inches) | |
|---|---|---|
| Type A | Type B | |
| 3 ⁄ 8 | 0.035 | 0.049 |
| 1 ⁄ 2 | 0.035 | 0.049 |
| 5 ⁄ 8 | 0.042 | 0.049 |
| 3 ⁄ 4 | 0.049 | 0.058 |
| 1 Based on data in Standard Specification for Aluminum-Alloy Drawn Seamless Coiled Tubes for Special Purpose Applications, ASTM B210-68. |
or less, fittings shall be designed for a pressure of at least 125 p.s.i.g. For operating pressures above 125 p.s.i.g., fittings shall be designed for a minimum of 250 p.s.i.g.
| Surface area (sq. ft.) | Flow rate CFM air |
|---|---|
| 20 or less | 626 |
| 25 | 751 |
| 30 | 872 |
| 35 | 990 |
| 40 | 1,100 |
| 45 | 1,220 |
| 50 | 1,330 |
| 55 | 1,430 |
| 60 | 1,540 |
| 65 | 1,640 |
| 70 | 1,750 |
| 75 | 1,850 |
| 80 | 1,950 |
| 85 | 2,050 |
| 90 | 2,150 |
| 95 | 2,240 |
| 100 | 2,340 |
| 105 | 2,440 |
| 110 | 2,530 |
| 115 | 2,630 |
| 120 | 2,720 |
| 125 | 2,810 |
| 130 | 2,900 |
| 135 | 2,990 |
| 140 | 3,080 |
| 145 | 3,170 |
| 150 | 3,260 |
| 155 | 3,350 |
| 160 | 3,440 |
| 165 | 3,530 |
| 170 | 3,620 |
| 175 | 3,700 |
| 180 | 3,790 |
| 185 | 3,880 |
| 190 | 3,960 |
| 195 | 4,050 |
| 200 | 4,130 |
| 210 | 4,300 |
| 220 | 4,470 |
| 230 | 4,630 |
| 240 | 4,800 |
| 250 | 4,960 |
| 260 | 5,130 |
| 270 | 5,290 |
| 280 | 5,450 |
| 290 | 5,610 |
| 300 | 5,760 |
| 310 | 5,920 |
| 320 | 6,080 |
| 330 | 6,230 |
| 340 | 6,390 |
| 350 | 6,540 |
| 360 | 6,690 |
| 370 | 6,840 |
| 380 | 7,000 |
| 390 | 7,150 |
| 400 | 7,300 |
| 450 | 8,040 |
| 500 | 8,760 |
| 550 | 9,470 |
| 600 | 10,170 |
| 650 | 10,860 |
| 700 | 11,550 |
| 750 | 12,220 |
| 800 | 12,880 |
| 850 | 13,540 |
| 900 | 14,190 |
| 950 | 14,830 |
| 1,000 | 15,470 |
| 1,050 | 16,100 |
| 1,100 | 16,720 |
| 1,150 | 17,350 |
| 1,200 | 17,960 |
| 1,250 | 18,570 |
| 1,300 | 19,180 |
| 1,350 | 19,780 |
| 1,400 | 20,380 |
| 1,450 | 20,980 |
| 1,500 | 21,570 |
| 1,550 | 22,160 |
| 1,600 | 22,740 |
| 1,650 | 23,320 |
| 1,700 | 23,900 |
| 1,750 | 24,470 |
| 1,800 | 25,050 |
| 1,850 | 25,620 |
| 1,900 | 26,180 |
| 1,950 | 26,750 |
| 2,000 | 27,310 |
Surface area = total outside surface area of container in square feet.
When the surface area is not stamped on the nameplate or when the marking is not legible, the area can be calculated by using one of the following formulas:
Area = Overall length × outside diameter × 3.1416.
Area = (Overall length + 0.3 outside diameter) × outside diameter × 3.1416.
| Container type | 100 | 125 | 150 | 175 | 200 |
|---|---|---|---|---|---|
| Air conversion factor | 1.162 | 1.142 | 1.113 | 1.078 | 1.010 |
The minimum required rate of discharge for safety relief valves shall be determined as follows:
Area = Outside diameter squared × 3.1416.
Flow Rate-CFM Air = Required flow capacity in cubic feet per minute of air at standard conditions, 60 F. and atmospheric pressure (14.7 p.s.i.a.).
The rate of discharge may be interpolated for intermediate values of surface area. For containers with total outside surface area greater than 2,000 square feet, the required flow rate can be calculated using the formula, Flow Rate-CFM Air = 53.632 A0.82.
A = total outside surface area of the container in square feet.
Valves not marked “Air” have flow rate marking in cubic feet per minute of liquefied petroleum gas. These can be converted to ratings in cubic feet per minute of air by multiplying the liquefied petroleum gas ratings by factors listed below. Air flow ratings can be converted to ratings in cubic feet per minute of liquefied petroleum gas by dividing the air ratings by the factors listed below.
| Containers | Minimum (percent) | Maximum (percent) |
|---|---|---|
| ASME Code; Par. U-68, U-69—1949 and earlier editions | 110 | 1 25 |
| ASME Code; Par. U-200, U-201—1949 edition | 88 | 1 100 |
| ASME Code—1950, 1952, 1956, 1959, 1962, 1965 and 1968 (Division I) editions | 88 | 1 100 |
| API—ASME Code—all editions | 88 | 1 100 |
| DOT—As prescribed in 49 CFR Chapter I | ||
| 1 Manufacturers of safety relief valves are allowed a plus tolerance not exceeding 10 percent of the set pressure marked on the valve. |
When vaporizing and/or mixing equipment is located in a structure or building not used exclusively for gas manufacturing or distribution, either attached to or within such a building, such structure or room shall be separated from the remainder of the building by a wall designed to withstand a static pressure of at least 100 pounds per square foot. This wall shall have no openings or pipe or conduit passing through it. Such structure or room shall be provided with adequate ventilation and shall have a roof or at least one exterior wall of lightweight construction.
Ten feet for vaporizers having a capacity of 15 gallons per hour or less vaporizing capacity.
Twenty-five feet for vaporizers having a vaporizing capacity of 16 to 100 gallons per hour.
Fifty feet for vaporizers having a vaporizing capacity exceeding 100 gallons per hour.
Ten feet for storage containers of less than 500 gallons water capacity.
Twenty-five feet for storage containers of 500 to 1,200 gallons water capacity.
Fifty feet for storage containers of over 1,200 gallons water capacity.
| Water capacity per container (gallons) | Minimum distances (feet) |
|---|---|
| Less than 501 | 10 |
| 501 to 2,000 | 25 |
| Over 2,000 | 50 |
| Specific gravity at 60 °F. (15.6 °C.) | Above ground containers | Under ground containers, all capacities | |
|---|---|---|---|
| 0 to 1,200 U.S. gals. (1,000 imp. gal., 4,550 liters) total water cap. | Over 1,200 U.S. gals. (1,000 imp. gal., 4,550 liters) total water cap. | ||
| Percent | Percent | Percent | |
| 0 .496-0 .503 | 41 | 44 | 45 |
| .504- .510 | 42 | 45 | 46 |
| .511- .519 | 43 | 46 | 47 |
| .520- .527 | 44 | 47 | 48 |
| .528- .536 | 45 | 48 | 49 |
| .537- .544 | 46 | 49 | 50 |
| .545- .552 | 47 | 50 | 51 |
| .553- .560 | 48 | 51 | 52 |
| .561- .568 | 49 | 52 | 53 |
| .569- .576 | 50 | 53 | 54 |
| .577- .584 | 51 | 54 | 55 |
| .585- .592 | 52 | 55 | 56 |
| .593- .600 | 53 | 56 | 57 |
The employer shall assure that (i) at least one attendant shall remain close to the transfer connection from the time the connections are first made until they are finally disconnected, during the transfer of the product.
Personnel performing installation, removal, operation, and maintenance work shall be properly trained in such function.
| Part | Location | Extent of classified area 1 | Equipment shall be suitable for Class 1, Group D 2 |
|---|---|---|---|
| A | Storage containers other than DOT cylinders | Within 15 feet in all directions from connections, except connections otherwise covered in Table H-28 | Division 2. |
| B | Tank vehicle and tank car loading and unloading 3 | Within 5 feet in all directions from connections regularly made or disconnected for product transfer | Division 1. |
| Beyond 5 feet but within 15 feet in all directions from a point where connections are regularly made or disconnected and within the cylindrical volume between the horizontal equator of the sphere and grade. (See Figure H-1) | Division 2. | ||
| C | Gage vent openings other than those on DOT cylinders | Within 5 feet in all directions from point of discharge Beyond 5 feet but within 15 feet in all directions from point of discharge | Division 1. |
| Division 2. | |||
| D | Relief valve discharge other than those on DOT cylinders | Within direct path of discharge | Division 1. |
| Within 5 feet in all directions from point of discharge | Division 1. | ||
| Beyond 5 feet but within 15 feet in all directions from point of discharge except within the direct path of discharge | Division 2. | ||
| E | Pumps, compressors, gas-air mixers and vaporizers other than direct fired | ||
| Indoors without ventilation | Entire room and any adjacent room not separated by a gastight partition | Division 1. | |
| Within 15 feet of the exterior side of any exterior wall or roof that is not vaportight or within 15 feet of any exterior opening | Division 2. | ||
| Indoors with adequate ventilation 4 | Entire room and any adjacent room not separated by a gastight partition | Division 2. | |
| Outdoors in open air at or abovegrade | Within 15 feet in all directions from this equipment and within the cylindrical volume between the horizontal equator of the sphere and grade. See Figure H-1 | Division 2. | |
| F | Service Station Dispensing Units | Entire space within dispenser enclosure, and 18 inches horizontally from enclosure exterior up to an elevation 4 ft. above dispenser base. Entire pit or open space beneath dispenser | Division 1. |
| Up to 18 inches abovegrade within 20 ft. horizontally from any edge of enclosure | Division 2. | ||
| Note: For pits within this area, see part F of this table. | |||
| G | Pits or trenches containing or located beneath LP-Gas valves, pumps, compressors, regulators, and similar equipment | ||
| Without mechanical ventilation | Entire pit or trench | Division 1. | |
| Entire room and any adjacent room not separated by a gastight partition | Division 1. | ||
| Within 15 feet in all directions from pit or trench when located outdoors | Division 2. | ||
| With adequate mechanical ventilation | Entire pit or trench | Division 2. | |
| Entire room and any adjacent room not separated by a gastight partition | Division 2. | ||
| Within 15 feet in all directions from pit or trench when located outdoors | Division 2. | ||
| H | Special buildings or rooms for storage of portable containers | Entire room | Division 2. |
| Pipelines and connections containing operational bleeds, drips, vents or drains | Within 5 ft. in all directions from point of discharge Beyond 5 ft. from point of discharge, same as part E of this table | Division 1. | |
| J | Container filling: | ||
| Indoors without ventilation | Entire room | Division 1. | |
| Indoors with adequate ventilation 4 | Within 5 feet in all directions from connections regularly made or disconnected for product transfer | Division 1. | |
| Beyond 5 feet and entire room | Division 2. | ||
| Outdoors in open air | Within 5 feet in all directions from connections regularly made or disconnected for product transfer | Division 1. | |
| Beyond 5 feet but within 15 feet in all directions from a point where connections are regularly made or disconnected and within the cylindrical volume between the horizontal equator of the sphere and grade. (See Figure H-1) | Division 2. | ||
| 1 The classified area shall not extend beyond an unpierced wall, roof, or solid vaportight partition. | |||
| 2 See subpart S of this part. | |||
| 3 When classifying extent of hazardous area, consideration shall be given to possible variations in the spotting of tank cars and tank vehicles at the unloading points and the effect these variations of actual spotting point may have on the point of connection. | |||
| 4 Ventilation, either natural or mechanical, is considered adequate when the concentration of the gas in a gas-air mixture does not exceed 25 percent of the lower flammable limit under normal operating conditions. |
Fixed electrical equipment and wiring installed within classified areas specified in Table H-28 shall comply with Table H-28 and shall be installed in accordance with subpart S of this part. This provision does not apply to fixed electrical equipment at residential or commercial installations of LP-Gas systems or to systems covered by paragraph (e) or (g) of this section.
[(Water capacity (gals.) of container* × filling density**) ÷ (Specific gravity of LP-Gas* × volume correction factor × 100)] = Maximum volume of LP-Gas
*Measured at 60 °F.
**From subparagraph (12) of this paragraph “Filling Densities.”
For aboveground containers the liquid temperature is assumed to be 40 °F. and for underground containers the liquid temperature is assumed to be 50 °F. To correct the liquid volumes at these temperatures to 60 °F. the following factors shall be used.
| Specific gravity | Aboveground | Underground |
|---|---|---|
| 0.500 | 1.033 | 1.017 |
| .510 | 1.031 | 1.016 |
| .520 | 1.029 | 1.015 |
| .530 | 1.028 | 1.014 |
| .540 | 1.026 | 1.013 |
| .550 | 1.025 | 1.013 |
| .560 | 1.024 | 1.012 |
| .570 | 1.023 | 1.011 |
| .580 | 1.021 | 1.011 |
| .590 | 1.020 | 1.010 |
Example:
Assume a 100-gallon total water capacity tank for aboveground storage of propane having a specific gravity of 0.510 of 60 °F.
[(100 (gals.) × 42 (filling density from subparagraph (12) of this paragraph)) ÷ (0.510 × 1.031 (correction factor from Table H-29) × 100)] = (4200 ÷ 52.6)
b
| Aboveground, pounds per gallon | Underground, pounds per gallon | |
|---|---|---|
| Propane | 4.37 | 4.31 |
| N Butane | 4.97 | 4.92 |
This paragraph applies specifically to systems utilizing containers constructed in accordance with DOT Specifications. All requirements of paragraph (b) of this section apply to this paragraph unless otherwise noted in paragraph (b) of this section.
Containers shall be marked in accordance with DOT regulations. Additional markings not in conflict with DOT regulations may be used.
A system shall include the container base or bracket, containers, container valves, connectors, manifold valve assembly, regulators, and relief valves.
Except as provided in paragraph (b)(10)(xiii) of this section, the discharge from safety relief devices shall be located not less than 3 feet horizontally away from any building opening which is below the level of such discharge and shall not terminate beneath any building unless such space is well ventilated to the outside and is not enclosed on more than two sides.
The provisions of this paragraph ( h ) do not apply to tar kettle burners, torches, melting pots, nor do they apply to portable heaters under 7,500 B.t.u.h. input when used with containers having a maximum water capacity of 2 1/2 pounds. Container valves, connectors, regulators, manifolds, piping, and tubing shall not be used as structural supports for heaters.
| Regulator delivery pressure | Relief valve start-to-discharge pressure setting (percent of regulator delivery pressure) | |
|---|---|---|
| Minimum | Maximum | |
| 1 p.s.i.g. or less | 200 | 300 |
| Above 1 p.s.i.g. but not over 3 p.s.i.g | 140 | 200 |
| Above 3 p.s.i.g | 125 | 200 |
Containers shall not be reinstalled unless they are requalified in accordance with DOT regulations.
A product shall not be placed in a container marked with a service pressure less than four-fifths of the maximum vapor pressure of product at 130 °F.
This paragraph applies specifically to systems utilizing storage containers other than those constructed in accordance with DOT specifications. Paragraph (b) of this section applies to this paragraph unless otherwise noted in paragraph (b) of this section.
Storage containers shall be designed and classified in accordance with Table H-31.
| Container type | For gases with vapor press. Not to exceed lb. per sq. in. gage at 100 °F. (37.8 °C.) | Minimum design pressure of container, lb. per sq. in. gage | |
|---|---|---|---|
| 1949 and earlier editions of ASME Code (Par. U-68, U-69) | 1949 edition of ASME Code (Par. U-200, U-201); 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of ASME Code; All editions of API-ASME Code 3 | ||
| 1 80 | 1 80 | 1 80 | 1 100 |
| 100 | 100 | 100 | 125 |
| 125 | 125 | 125 | 156 |
| 150 | 150 | 150 | 187 |
| 175 | 175 | 175 | 219 |
| 2 200 | 215 | 200 | 250 |
| 1 New storage containers of the 80 type have not been authorized since Dec. 31, 1947. | |||
| 2 Container type may be increased by increments of 25. The minimum design pressure of containers shall be 100% of the container type designation when constructed under 1949 or earlier editions of the ASME Code (Par. U-68 and U-69). The minimum design pressure of containers shall be 125% of the container type designation when constructed under: (1) the 1949 ASME Code (Par. U-200 and U-201), (2) 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of the ASME Code, and (3) all editions of the API-ASME Code. | |||
| 3 Construction of containers under the API-ASME Code is not authorized after July 1, 1961. |
Where there is a probability of the manhole or housing becoming flooded, the discharge from regulator vent lines shall be above the highest probable water level. All manholes or housings shall be provided with ventilated louvers or their equivalent, the area of such openings equaling or exceeding the combined discharge areas of the safety relief valves and other vent lines which discharge their content into the manhole housing.
Containers may be reinstalled if they do not show any evidence of harmful external corrosion or other damage. Where containers are reinstalled underground, the corrosion resistant coating shall be put in good condition (see paragraph (c)(7)(vi) of this section). Where containers are reinstalled above ground, the safety devices and gaging devices shall comply with paragraph (c)(4) of this section and paragraph (b)(19) of this section respectively for aboveground containers.
A storage container shall not exceed 90,000 gallons water capacity.
It will not be necessary to cover the portion of the container to which manhole and other connections are affixed; however, where necessary, protection shall be provided against vehicular damage. When necessary to prevent floating, containers shall be securely anchored or weighted.
Where vaporized gas on the low-pressure side of the system may condense to a liquid at normal operating temperatures and pressures, suitable means shall be provided for revaporization of the condensate.
When damage to LP-Gas systems from vehicular traffic is a possibility, precautions against such damage shall be taken.
No drains or blowoff lines shall be directed into or in proximity to sewer systems used for other purposes.
Electrical equipment and installations shall conform to paragraphs (b) (17) and (18) of this section.
The provisions of paragraph (e)(8) of this section shall apply.
| Container type | For gases with vapor press. Not to exceed lb. per sq. in. gage at 100 °F. (37.8 °C.) | Minimum design pressure of container, lb. per sq. in. gage | |
|---|---|---|---|
| 1949 and earlier editions of ASME Code (Par. U-68, U-69) | 1949 edition of ASME Code (Par. U-200, U-201); 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of ASME Code; All editions of API-ASME Code 2 | ||
| 1 200 | 215Z | 200 | 250 |
| 1 Container type may be increased by increments of 25. The minimum design pressure of containers shall be 100% of the container type designation when constructed under 1949 or earlier editions of the ASME Code (Par. U-68 and U-69). The minimum design pressure of containers shall be 125% of the container type designation when constructed under: (1) the 1949 ASME Code (Par. U-200 and U-201), (2) 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of the ASME Code, and (3) all editions of the API-ASME Code. | |||
| 2 Construction of containers under the API-ASME Code is not authorized after July 1, 1961. |
Stationary engines and gas turbines installed in buildings, including portable engines used instead of or to supplement stationary engines, shall comply with the Standard for the Institution and Use of Stationary Combustion Engines and Gas Turbines, NFPA 37-1970, and the appropriate provisions of paragraphs (b), (c), and (d) of this section.
This paragraph shall apply to the storage of portable containers not in excess of 1,000 pounds water capacity, filled or partially filled, at user location but not connected for use, or in storage for resale by dealers or resellers. This paragraph shall not apply to containers stored at charging plants or at plants devoted primarily to the storage and distribution of LP-Gas or other petroleum products.
| Quantity of LP-Gas Stored | Distance |
|---|---|
| 500 pounds or less | 0 |
| 501 to 2,500 pounds | 1 0 |
| 2,501 to 6,000 pounds | 10 feet |
| 6,001 to 10,000 pounds | 20 feet |
| Over 10,000 pounds | 25 feet |
| 1 Container or containers shall be at least 10 feet from any building on adjoining property, any sidewalk, or any of the exposures described in § 1910.110(f)(6)(i) ( c ) or ( d ) of this paragraph. |
Storage locations other than supply depots separated and located apart from dealer, reseller, or user establishments shall be provided with at least one approved portable fire extinguisher having a minimum rating of 8-B, C.
This paragraph applies to storage containers, and dispensing devices, and pertinent equipment in service stations where LP-Gas is stored and is dispensed into fuel tanks of motor vehicles. See paragraph (e) of this section for requirements covering use of LP-Gas as a motor fuel. All requirements of paragraph (b) of this section apply to this paragraph unless otherwise noted.
Storage containers shall be designed and classified in accordance with Table H-34.
| Container type | For gases with vapor press. Not to exceed lb. per sq. in. gage at 100 °F. (37.8 °C.) | Minimum design pressure of container, lb. per sq. in. gage | |
|---|---|---|---|
| 1949 and earlier editions of ASME Code (Par. U-68, U-69) | 1949 edition of ASME Code (Par. U-200, U-201); 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of ASME Code; All editions of API-ASME Code 2 | ||
| 1 200 | 215 | 200 | 250 |
| 1 Container type may be increased by increments of 25. The minimum design pressure of containers shall be 100 percent of the container type designation when constructed under 1949 or earlier editions of the ASME Code (Par. U-68 and U-69). The minimum design pressure of containers shall be 125 percent of the container type designation when constructed under: (1) The 1949 ASME Code (Paragraphs U-200 and U-201), (2) 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of the ASME Code, and (3) all editions of the API-ASME Code. | |||
| 2 Construction of containers under the API-ASME Code is not authorized after July 1, 1961. |
In lieu of an excess flow valve, filling connections may be fitted with a quick-closing internal valve, which shall remain closed except during operating periods. The mechanism for such valves may be provided with a secondary control which will cause it to close automatically in case of fire. When a fusible plug is used its melting point shall not exceed 220 °F.
Individual liquid storage containers shall not exceed 30,000 gallons water capacity.
| Water capacity per container (gallons) | Minimum distances | |
|---|---|---|
| Aboveground and underground (feet) | Between aboveground containers (feet) | |
| Up to 2,000 | 25 | 3 |
| Over 2,000 | 50 | 5 |
| Note: The above distances may be reduced to not less than 10 feet for service station buildings of other than wood frame construction. |
Valves, regulators, gages, and other container fittings shall be protected against tampering and physical damage.
All pumps and accessory equipment shall be suitable for LP-Gas service, and designed for not less than the maximum pressure to which they may be subjected. Accessories shall have a minimum rated working pressure of 250 p.s.i.g. Positive displacement pumps shall be equipped with suitable pressure actuated bypass valves permitting flow from pump discharge to storage container or pump suction.
There shall be no smoking on the driveway of service stations in the dispensing areas or transport truck unloading areas. Conspicuous signs prohibiting smoking shall be posted within sight of the customer being served. Letters on such signs shall be not less than 4 inches high. The motors of all vehicles being fueled shall be shut off during the fueling operations.
Electrical equipment and installations shall conform to paragraphs (b) (17) and (18) of this section.
Each service station shall be provided with at least one approved portable fire extinguisher having at least an 8-B, C, rating.
This section does not apply to:
The requirements of § 1910.253 shall apply to such use;
The National Fire Protection Association Standard for the Storage and Handling of Liquefied Petroleum Gases at Utility Gas Plants, NFPA No. 59-1968, shall apply to such use;
Unless otherwise stated, it is not intended that the provisions of this section be retroactive.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49747, Oct. 24, 1978; 49 FR 5322, Feb. 10, 1984; 53 FR 12122, Apr. 12, 1988; 55 FR 25094, June 20, 1990; 55 FR 32015, Aug. 6, 1990; 58 FR 35309, June 30, 1993; 61 FR 9237, 9238, Mar. 7, 1996; 63 FR 33466, June 18, 1998; 72 FR 71069, Dec. 14, 2007]
As used in this section.
All devices such as pumps, compressors, safety relief devices, liquid-level gaging devices, valves and pressure gages.
A container of 1,000 pounds of water capacity or less constructed in accordance with Department of Transportation specifications.
The Boiler and Pressure Vessel Code, Section VIII, Unfired Pressure Vessels of the American Society of Mechanical Engineers (ASME)—1968.
Includes all vessels, tanks, cylinders, or spheres used for transportation, storage, or application of anhydrous ammonia.
U.S. Department of Transportation.
A vehicle for use on a farm on which is mounted a container of not over 1,200 gallons water capacity.
the percent ratio of the weight of the gas in a container to the weight of water at 60 °F. that the container will hold.
Anhydrous ammonia in either the gaseous or liquefied state.
Gas masks must be approved by the National Institute for Occupational Safety and Health (NIOSH) under 42 CFR part 84 for use with anhydrous ammonia.
Total volume of the container in standard U.S. gallons.
specifications—Regulations of the Department of Transportation published in 49 CFR chapter I.
This paragraph applies to all paragraphs of this section unless otherwise noted.
Each appurtenance shall be approved in accordance with paragraph (b)(1) (i), (ii), (iii), or (iv) of this section.
Under ground: Container and system nameplate.
Above ground: Container.
Under ground and above ground: System nameplate.
Under ground: Container and system nameplate.
Above ground: Container.
Under ground: Container and system nameplate.
Above ground: Container.
Under ground: Container and system nameplate.
Above ground: Container.
Above ground and under ground: System nameplate or on liquid-level gaging device.
Under ground: System nameplate.
Above ground: No requirement.
Each refrigerated container shall be marked with nameplate on the outer covering in an accessible place as specified in the following:
“Anhydrous Ammonia” xxx p.s.i.g. (maximum working pressure), manufacturer's name or trademark, year of manufacture.
In lieu of this requirement the same information may be contained on a nameplate permanently attached to the hose.
| Surface area (sq. ft.) | Flow rate CFM air |
|---|---|
| 20 | 258 |
| 25 | 310 |
| 30 | 360 |
| 35 | 408 |
| 40 | 455 |
| 45 | 501 |
| 50 | 547 |
| 55 | 591 |
| 60 | 635 |
| 65 | 678 |
| 70 | 720 |
| 75 | 762 |
| 80 | 804 |
| 85 | 845 |
| 90 | 885 |
| 95 | 925 |
| 100 | 965 |
| 105 | 1,010 |
| 110 | 1,050 |
| 115 | 1,090 |
| 120 | 1,120 |
| 125 | 1,160 |
| 130 | 1,200 |
| 135 | 1,240 |
| 140 | 1,280 |
| 145 | 1,310 |
| 150 | 1,350 |
| 155 | 1,390 |
| 160 | 1,420 |
| 165 | 1,460 |
| 170 | 1,500 |
| 175 | 1,530 |
| 180 | 1,570 |
| 185 | 1,600 |
| 190 | 1,640 |
| 195 | 1,670 |
| 200 | 1,710 |
| 210 | 1,780 |
| 220 | 1,850 |
| 230 | 1,920 |
| 240 | 1,980 |
| 250 | 2,050 |
| 260 | 2,120 |
| 270 | 2,180 |
| 280 | 2,250 |
| 290 | 2,320 |
| 300 | 2,380 |
| 310 | 2,450 |
| 320 | 2,510 |
| 330 | 2,570 |
| 340 | 2,640 |
| 350 | 2,700 |
| 360 | 2,760 |
| 370 | 2,830 |
| 380 | 2,890 |
| 390 | 2,950 |
| 400 | 3,010 |
| 450 | 3,320 |
| 500 | 3,620 |
| 550 | 3,910 |
| 600 | 4,200 |
| 650 | 4,480 |
| 700 | 4,760 |
| 750 | 5,040 |
| 800 | 5,300 |
| 850 | 5,590 |
| 900 | 5,850 |
| 950 | 6,120 |
| 1,000 | 6,380 |
| 1,050 | 6,640 |
| 1,100 | 6,900 |
| 1,150 | 7,160 |
| 1,200 | 7,410 |
| 1,250 | 7,660 |
| 1,300 | 7,910 |
| 1,350 | 8,160 |
| 1,400 | 8,410 |
| 1,450 | 8,650 |
| 1,500 | 8,900 |
| 1,550 | 9,140 |
| 1,600 | 9,380 |
| 1,650 | 9,620 |
| 1,700 | 9,860 |
| 1,750 | 10,090 |
| 1,800 | 10,330 |
| 1,850 | 10,560 |
| 1,900 | 10,800 |
| 1,950 | 11,030 |
| 2,000 | 11,260 |
| 2,050 | 11,490 |
| 2,100 | 11,720 |
| 2,150 | 11,950 |
| 2,200 | 12,180 |
| 2,250 | 12,400 |
| 2,300 | 12,630 |
| 2,350 | 12,850 |
| 2,400 | 13,080 |
| 2,450 | 13,300 |
| 2,500 | 13,520 |
Surface Area = total outside surface area of container in square feet. When the surface area is not stamped on the nameplate or when the marking is not legible the area can be calculated by using one of the following formulas:
Area = overall length in feet times outside diameter in feet times 3.1416.
Area = (overall length in feet plus 0.3 outside diameter in feet) times outside diameter in feet times 3.1416.
Area = outside diameter in feet squared times 3.1416.
Flow Rate—CFM Air = cubic feet per minute of air required at standard conditions, 60 °F. and atmospheric pressure (14.7 p.s.i.a.).
The rate of discharge may be interpolated for intermediate values of surface area. For containers with total outside surface area greater than 2,500 square feet, the required flow rate can be calculated using the formula: Flow Rate CFM Air = 22.11 A 0 82, where A = outside surface area of the container in square feet.
| Containers | Minimum (percent) | Maximum (percent) |
|---|---|---|
| ASME-U-68, U-69 | 110 | 125 |
| ASME-U-200, U-201 | 95 | 100 |
| ASME 1959, 1956, 1952, or 1962 | 95 | 100 |
| API-ASME | 95 | 100 |
| U.S. Coast Guard | 95 | 100 |
As required by DOT Regulations.
| Type of container | Percent by weight | Percent by volume |
|---|---|---|
| Aboveground-Uninsulated | 56 | 82 |
| Aboveground-Uninsulated | 87.5 | |
| Aboveground-Insulated | 57 | 83.5 |
| Underground-Uninsulated | 58 | 85 |
| DOT—In accord with DOT regulations. |
The minimum design pressure for nonrefrigerated containers shall be 250 p.s.i.g.
Precaution shall be taken against damage to ammonia systems from vehicles.
This paragraph applies to systems utilizing containers with the storage of anhydrous ammonia under refrigerated conditions. All applicable rules of paragraph (b) of this section apply to this paragraph unless otherwise noted.
shall be constructed in accordance with paragraph (b)(2) of this section, and the materials shall be selected from those listed in API Standard 620, Recommended Rules for Design and Construction of Large, Welded, Low-Pressure Storage Tanks, Fourth Edition, 1970, Tables 2.02, R2.2, R2.2(A), R2.2.1, or R2.3 which are incorporated by reference as specified in § 1910.6.
and less shall be constructed in accordance with the applicable requirements of API Standard 620 including its appendix R.
When operating conditions make it advisable, a check valve shall be installed on the fill connection and a remotely operated shutoff valve on other connections located below the maximum liquid level.
Appurtenances shall be protected against tampering and physical damage.
Containers of such size as to require field fabrication shall, when moved and reinstalled, be reconstructed and reinspected in complete accordance with the requirements under which they were constructed. The containers shall be subjected to a pressure retest and if rerating is necessary, rerating shall be in accordance with applicable requirements.
Precaution shall be taken against damage from vehicles.
The condenser system may be cooled by air or water or both. The condenser shall be designed for at least 250 p.s.i.g. Provision shall be made for purging noncondensibles either manually or automatically.
A receiver shall be provided with a liquid-level control to discharge the liquid ammonia to storage. The receiver shall be designed for at least 250 p.s.i.g. and be equipped with the necessary connections, safety valves, and gaging device.
Refrigerated containers and pipelines which are insulated shall be covered with a material of suitable quality and thickness for the temperatures encountered. Insulation shall be suitably supported and protected against the weather. Weatherproofing shall be of a type which will not support flame propagation.
Cylinders shall comply with DOT specifications and shall be maintained, filled, packaged, marked, labeled, and shipped to comply with 49 CFR chapter I and the marking requirements set forth in § 1910.253(b)(1)(ii).
Cylinders shall be stored in an area free from ignitable debris and in such manner as to prevent external corrosion. Storage may be indoors or outdoors.
Cylinders filled in accordance with DOT regulations will become liquid full at 145 °F. Cylinders shall be protected from heat sources such as radiant flame and steampipes. Heat shall not be applied directly to cylinders to raise the pressure.
Cylinders shall be stored in such manner as to protect them from moving vehicles or external damage.
Any cylinder which is designed to have a valve protection cap shall have the cap securely in place when the cylinder is not in service.
Paragraph (b) of this section applies to this paragraph unless otherwise noted. Containers and pertinent equipment for tank motor vehicles for the transportation of anhydrous ammonia, in addition to complying with the requirements of this section, shall also comply with the requirements of DOT.
At least two chock blocks shall be provided. These blocks shall be placed to prevent rolling of the vehicle whenever it is parked during loading and unloading operations.
Where portable tank containers are used for farm storage they shall comply with paragraph (c)(1) of this section. When portable tank containers are used in lieu of cargo tanks and are permanently mounted on tank motor vehicles for the transportation of ammonia, they shall comply with the requirements of this paragraph.
This paragraph applies to containers of 1,200 gallons capacity or less and pertinent equipment mounted on farm vehicles (implements of husbandry) and used other than for the application of ammonia to the soil. Paragraph (b) of this section applies to this paragraph unless otherwise noted.
There shall appear on each side and on the rear end of the container in letters at least 4 inches high, the words, “Caution—Ammonia” or the container shall be marked in accordance with DOT regulations.
All containers and flow-control devices shall be securely mounted.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49748, Oct. 24, 1978; 49 FR 5322, Feb. 10, 1984; 53 FR 12122, Apr. 12, 1988; 61 FR 9238, Mar. 7, 1996; 63 FR 1269, Jan. 8, 1998; 63 FR 33466, June 18, 1998; 72 FR 71069, Dec. 14, 2007]
Purpose. This section contains requirements for preventing or minimizing the consequences of catastrophic releases of toxic, reactive, flammable, or explosive chemicals. These releases may result in toxic, fire or explosion hazards.
Atmospheric tank means a storage tank which has been designed to operate at pressures from atmospheric through 0.5 p.s.i.g. (pounds per square inch gauge, 3.45 Kpa).
Boiling point means the boiling point of a liquid at a pressure of 14.7 pounds per square inch absolute (p.s.i.a.) (760 mm.). For the purposes of this section, where an accurate boiling point is unavailable for the material in question, or for mixtures which do not have a constant boiling point, the 10 percent point of a distillation performed in accordance with the Standard Method of Test for Distillation of Petroleum Products, ASTM D-86-62, which is incorporated by reference as specified in § 1910.6, may be used as the boiling point of the liquid.
Catastrophic release means a major uncontrolled emission, fire, or explosion, involving one or more highly hazardous chemicals, that presents serious danger to employees in the workplace.
Facility means the buildings, containers or equipment which contain a process.
Highly hazardous chemical means a substance possessing toxic, reactive, flammable, or explosive properties and specified by paragraph (a)(1) of this section.
Hot work means work involving electric or gas welding, cutting, brazing, or similar flame or spark-producing operations.
Normally unoccupied remote facility means a facility which is operated, maintained or serviced by employees who visit the facility only periodically to check its operation and to perform necessary operating or maintenance tasks. No employees are permanently stationed at the facility.
Facilities meeting this definition are not contiguous with, and must be geographically remote from all other buildings, processes or persons.
Process means any activity involving a highly hazardous chemical including any use, storage, manufacturing, handling, or the on-site movement of such chemicals, or combination of these activities. For purposes of this definition, any group of vessels which are interconnected and separate vessels which are located such that a highly hazardous chemical could be involved in a potential release shall be considered a single process.
Replacement in kind means a replacement which satisfies the design specification.
Trade secret means any confidential formula, pattern, process, device, information or compilation of information that is used in an employer's business, and that gives the employer an opportunity to obtain an advantage over competitors who do not know or use it. See Appendix E to § 1910.1200—Definition of a Trade Secret (which sets out the criteria to be used in evaluating trade secrets).
In accordance with the schedule set forth in paragraph (e)(1) of this section, the employer shall complete a compilation of written process safety information before conducting any process hazard analysis required by the standard. The compilation of written process safety information is to enable the employer and the employees involved in operating the process to identify and understand the hazards posed by those processes involving highly hazardous chemicals. This process safety information shall include information pertaining to the hazards of the highly hazardous chemicals used or produced by the process, information pertaining to the technology of the process, and information pertaining to the equipment in the process.
interlocks, detection or suppression systems).
Refresher training shall be provided at least every three years, and more often if necessary, to each employee involved in operating a process to assure that the employee understands and adheres to the current operating procedures of the process. The employer, in consultation with the employees involved in operating the process, shall determine the appropriate frequency of refresher training.
The employer shall ascertain that each employee involved in operating a process has received and understood the training required by this paragraph. The employer shall prepare a record which contains the identity of the employee, the date of training, and the means used to verify that the employee understood the training.
This paragraph applies to contractors performing maintenance or repair, turnaround, major renovation, or specialty work on or adjacent to a covered process. It does not apply to contractors providing incidental services which do not influence process safety, such as janitorial work, food and drink services, laundry, delivery or other supply services.
Paragraphs (j)(2) through (j)(6) of this section apply to the following process equipment:
The employer shall establish and implement written procedures to maintain the on-going integrity of process equipment.
The employer shall train each employee involved in maintaining the on-going integrity of process equipment in an overview of that process and its hazards and in the procedures applicable to the employee's job tasks to assure that the employee can perform the job tasks in a safe manner.
The employer shall correct deficiencies in equipment that are outside acceptable limits (defined by the process safety information in paragraph (d) of this section) before further use or in a safe and timely manner when necessary means are taken to assure safe operation.
The employer shall establish and implement an emergency action plan for the entire plant in accordance with the provisions of 29 CFR 1910.38. In addition, the emergency action plan shall include procedures for handling small releases. Employers covered under this standard may also be subject to the hazardous waste and emergency response provisions contained in 29 CFR 1910.120 (a), (p) and (q).
Appendix A to § 1910.119—List of Highly Hazardous Chemicals, Toxics and Reactives (Mandatory)
This appendix contains a listing of toxic and reactive highly hazardous chemicals which present a potential for a catastrophic event at or above the threshold quantity.
| Chemical name | CAS * | TQ ** |
|---|---|---|
| Acetaldehyde | 75-07-0 | 2500 |
| Acrolein (2-Propenal) | 107-02-8 | 150 |
| Acrylyl Chloride | 814-68-6 | 250 |
| Allyl Chloride | 107-05-1 | 1000 |
| Allylamine | 107-11-9 | 1000 |
| Alkylaluminums | Varies | 5000 |
| Ammonia, Anhydrous | 7664-41-7 | 10000 |
| Ammonia solutions (>44% ammonia by weight) | 7664-41-7 | 15000 |
| Ammonium Perchlorate | 7790-98-9 | 7500 |
| Ammonium Permanganate | 7787-36-2 | 7500 |
| Arsine (also called Arsenic Hydride) | 7784-42-1 | 100 |
| Bis(Chloromethyl) Ether | 542-88-1 | 100 |
| Boron Trichloride | 10294-34-5 | 2500 |
| Boron Trifluoride | 7637-07-2 | 250 |
| Bromine | 7726-95-6 | 1500 |
| Bromine Chloride | 13863-41-7 | 1500 |
| Bromine Pentafluoride | 7789-30-2 | 2500 |
| Bromine Trifluoride | 7787-71-5 | 15000 |
| 3-Bromopropyne (also called Propargyl Bromide) | 106-96-7 | 100 |
| Butyl Hydroperoxide (Tertiary) | 75-91-2 | 5000 |
| Butyl Perbenzoate (Tertiary) | 614-45-9 | 7500 |
| Carbonyl Chloride (see Phosgene) | 75-44-5 | 100 |
| Carbonyl Fluoride | 353-50-4 | 2500 |
| Cellulose Nitrate (concentration >12.6% nitrogen) | 9004-70-0 | 2500 |
| Chlorine | 7782-50-5 | 1500 |
| Chlorine Dioxide | 10049-04-4 | 1000 |
| Chlorine Pentrafluoride | 13637-63-3 | 1000 |
| Chlorine Trifluoride | 7790-91-2 | 1000 |
| Chlorodiethylaluminum (also called Diethylaluminum Chloride) | 96-10-6 | 5000 |
| 1-Chloro-2,4-Dinitrobenzene | 97-00-7 | 5000 |
| Chloromethyl Methyl Ether | 107-30-2 | 500 |
| Chloropicrin | 76-06-2 | 500 |
| Chloropicrin and Methyl Bromide mixture | None | 1500 |
| Chloropicrin and Methyl Chloride mixture | None | 1500 |
| Cumene Hydroperoxide | 80-15-9 | 5000 |
| Cyanogen | 460-19-5 | 2500 |
| Cyanogen Chloride | 506-77-4 | 500 |
| Cyanuric Fluoride | 675-14-9 | 100 |
| Diacetyl Peroxide (Concentration >70%) | 110-22-5 | 5000 |
| Diazomethane | 334-88-3 | 500 |
| Dibenzoyl Peroxide | 94-36-0 | 7500 |
| Diborane | 19287-45-7 | 100 |
| Dibutyl Peroxide (Tertiary) | 110-05-4 | 5000 |
| Dichloro Acetylene | 7572-29-4 | 250 |
| Dichlorosilane | 4109-96-0 | 2500 |
| Diethylzinc | 557-20-0 | 10000 |
| Diisopropyl Peroxydicarbonate | 105-64-6 | 7500 |
| Dilaluroyl Peroxide | 105-74-8 | 7500 |
| Dimethyldichlorosilane | 75-78-5 | 1000 |
| Dimethylhydrazine, 1,1- | 57-14-7 | 1000 |
| Dimethylamine, Anhydrous | 124-40-3 | 2500 |
| 2,4-Dinitroaniline | 97-02-9 | 5000 |
| Ethyl Methyl Ketone Peroxide (also Methyl Ethyl Ketone Peroxide; concentration >60%) | 1338-23-4 | 5000 |
| Ethyl Nitrite | 109-95-5 | 5000 |
| Ethylamine | 75-04-7 | 7500 |
| Ethylene Fluorohydrin | 371-62-0 | 100 |
| Ethylene Oxide | 75-21-8 | 5000 |
| Ethyleneimine | 151-56-4 | 1000 |
| Fluorine | 7782-41-4 | 1000 |
| Formaldehyde (Formalin) | 50-00-0 | 1000 |
| Furan | 110-00-9 | 500 |
| Hexafluoroacetone | 684-16-2 | 5000 |
| Hydrochloric Acid, Anhydrous | 7647-01-0 | 5000 |
| Hydrofluoric Acid, Anhydrous | 7664-39-3 | 1000 |
| Hydrogen Bromide | 10035-10-6 | 5000 |
| Hydrogen Chloride | 7647-01-0 | 5000 |
| Hydrogen Cyanide, Anhydrous | 74-90-8 | 1000 |
| Hydrogen Fluoride | 7664-39-3 | 1000 |
| Hydrogen Peroxide (52% by weight or greater) | 7722-84-1 | 7500 |
| Hydrogen Selenide | 7783-07-5 | 150 |
| Hydrogen Sulfide | 7783-06-4 | 1500 |
| Hydroxylamine | 7803-49-8 | 2500 |
| Iron, Pentacarbonyl | 13463-40-6 | 250 |
| Isopropylamine | 75-31-0 | 5000 |
| Ketene | 463-51-4 | 100 |
| Methacrylaldehyde | 78-85-3 | 1000 |
| Methacryloyl Chloride | 920-46-7 | 150 |
| Methacryloyloxyethyl Isocyanate | 30674-80-7 | 100 |
| Methyl Acrylonitrile | 126-98-7 | 250 |
| Methylamine, Anhydrous | 74-89-5 | 1000 |
| Methyl Bromide | 74-83-9 | 2500 |
| Methyl Chloride | 74-87-3 | 15000 |
| Methyl Chloroformate | 79-22-1 | 500 |
| Methyl Ethyl Ketone Peroxide (concentration >60%) | 1338-23-4 | 5000 |
| Methyl Fluoroacetate | 453-18-9 | 100 |
| Methyl Fluorosulfate | 421-20-5 | 100 |
| Methyl Hydrazine | 60-34-4 | 100 |
| Methyl Iodide | 74-88-4 | 7500 |
| Methyl Isocyanate | 624-83-9 | 250 |
| Methyl Mercaptan | 74-93-1 | 5000 |
| Methyl Vinyl Ketone | 78-94-4 | 100 |
| Methyltrichlorosilane | 75-79-6 | 500 |
| Nickel Carbonly (Nickel Tetracarbonyl) | 13463-39-3 | 150 |
| Nitric Acid (94.5% by weight or greater) | 7697-37-2 | 500 |
| Nitric Oxide | 10102-43-9 | 250 |
| Nitroaniline (para Nitroaniline | 100-01-6 | 5000 |
| Nitromethane | 75-52-5 | 2500 |
| Nitrogen Dioxide | 10102-44-0 | 250 |
| Nitrogen Oxides (NO; NO 2 ; N204; N203) | 10102-44-0 | 250 |
| Nitrogen Tetroxide (also called Nitrogen Peroxide) | 10544-72-6 | 250 |
| Nitrogen Trifluoride | 7783-54-2 | 5000 |
| Nitrogen Trioxide | 10544-73-7 | 250 |
| Oleum (65% to 80% by weight; also called Fuming Sulfuric Acid) | 8014-95-7 | 1,000 |
| Osmium Tetroxide | 20816-12-0 | 100 |
| Oxygen Difluoride (Fluorine Monoxide) | 7783-41-7 | 100 |
| Ozone | 10028-15-6 | 100 |
| Pentaborane | 19624-22-7 | 100 |
| Peracetic Acid (concentration >60% Acetic Acid; also called Peroxyacetic Acid) | 79-21-0 | 1000 |
| Perchloric Acid (concentration >60% by weight) | 7601-90-3 | 5000 |
| Perchloromethyl Mercaptan | 594-42-3 | 150 |
| Perchloryl Fluoride | 7616-94-6 | 5000 |
| Peroxyacetic Acid (concentration >60% Acetic Acid; also called Peracetic Acid) | 79-21-0 | 1000 |
| Phosgene (also called Carbonyl Chloride) | 75-44-5 | 100 |
| Phosphine (Hydrogen Phosphide) | 7803-51-2 | 100 |
| Phosphorus Oxychloride (also called Phosphoryl Chloride) | 10025-87-3 | 1000 |
| Phosphorus Trichloride | 7719-12-2 | 1000 |
| Phosphoryl Chloride (also called Phosphorus Oxychloride) | 10025-87-3 | 1000 |
| Propargyl Bromide | 106-96-7 | 100 |
| Propyl Nitrate | 627-3-4 | 2500 |
| Sarin | 107-44-8 | 100 |
| Selenium Hexafluoride | 7783-79-1 | 1000 |
| Stibine (Antimony Hydride) | 7803-52-3 | 500 |
| Sulfur Dioxide (liquid) | 7446-09-5 | 1000 |
| Sulfur Pentafluoride | 5714-22-7 | 250 |
| Sulfur Tetrafluoride | 7783-60-0 | 250 |
| Sulfur Trioxide (also called Sulfuric Anhydride) | 7446-11-9 | 1000 |
| Sulfuric Anhydride (also called Sulfur Trioxide) | 7446-11-9 | 1000 |
| Tellurium Hexafluoride | 7783-80-4 | 250 |
| Tetrafluoroethylene | 116-14-3 | 5000 |
| Tetrafluorohydrazine | 10036-47-2 | 5000 |
| Tetramethyl Lead | 75-74-1 | 1000 |
| Thionyl Chloride | 7719-09-7 | 250 |
| Trichloro (chloromethyl) Silane | 1558-25-4 | 100 |
| Trichloro (dichlorophenyl) Silane | 27137-85-5 | 2500 |
| Trichlorosilane | 10025-78-2 | 5000 |
| Trifluorochloroethylene | 79-38-9 | 10000 |
| Trimethyoxysilane | 2487-90-3 | 1500 |
| * Chemical Abstract Service Number. | ||
| ** Threshold Quantity in Pounds (Amount necessary to be covered by this standard). |
Appendix C to § 1910.119—Compliance Guidelines and Recommendations for Process Safety Management (Nonmandatory)
This appendix serves as a nonmandatory guideline to assist employers and employees in complying with the requirements of this section, as well as provides other helpful recommendations and information. Examples presented in this appendix are not the only means of achieving the performance goals in the standard. This appendix neither adds nor detracts from the requirements of the standard.
1. Introduction to Process Safety Management. The major objective of process safety management of highly hazardous chemicals is to prevent unwanted releases of hazardous chemicals especially into locations which could expose employees and others to serious hazards. An effective process safety management program requires a systematic approach to evaluating the whole process. Using this approach the process design, process technology, operational and maintenance activities and procedures, nonroutine activities and procedures, emergency preparedness plans and procedures, training programs, and other elements which impact the process are all considered in the evaluation. The various lines of defense that have been incorporated into the design and operation of the process to prevent or mitigate the release of hazardous chemicals need to be evaluated and strengthened to assure their effectiveness at each level. Process safety management is the proactive identification, evaluation and mitigation or prevention of chemical releases that could occur as a result of failures in process, procedures or equipment.
The process safety management standard targets highly hazardous chemicals that have the potential to cause a catastrophic incident. This standard as a whole is to aid employers in their efforts to prevent or mitigate episodic chemical releases that could lead to a catastrophe in the workplace and possibly to the surrounding community. To control these types of hazards, employers need to develop the necessary expertise, experiences, judgement and proactive initiative within their workforce to properly implement and maintain an effective process safety management program as envisioned in the OSHA standard. This OSHA standard is required by the Clean Air Act Amendments as is the Environmental Protection Agency's Risk Management Plan. Employers, who merge the two sets of requirements into their process safety management program, will better assure full compliance with each as well as enhancing their relationship with the local community.
While OSHA believes process safety management will have a positive effect on the safety of employees in workplaces and also offers other potential benefits to employers (increased productivity), smaller businesses which may have limited resources available to them at this time, might consider alternative avenues of decreasing the risks associated with highly hazardous chemicals at their workplaces. One method which might be considered is the reduction in the inventory of the highly hazardous chemical. This reduction in inventory will result in a reduction of the risk or potential for a catastrophic incident. Also, employers including small employers may be able to establish more efficient inventory control by reducing the quantities of highly hazardous chemicals on site below the established threshold quantities. This reduction can be accomplished by ordering smaller shipments and maintaining the minimum inventory necessary for efficient and safe operation. When reduced inventory is not feasible, then the employer might consider dispersing inventory to several locations on site. Dispersing storage into locations where a release in one location will not cause a release in another location is a practical method to also reduce the risk or portential for catastrophic incidents.
2. Employee Involvement in Process Safety Management. Section 304 of the Clean Air Act Amendments states that employers are to consult with their employees and their representatives regarding the employers efforts in the development and implementation of the process safety management program elements and hazard assessments. Section 304 also requires employers to train and educate their employees and to inform affected employees of the findings from incident investigations required by the process safety management program. Many employers, under their safety and health programs, have already established means and methods to keep employees and their representatives informed about relevant safety and health issues and employers may be able to adapt these practices and procedures to meet their obligations under this standard. Employers who have not implemented an occupational safety and health program may wish to form a safety and health committee of employees and management representatives to help the employer meet the obligations specified by this standard. These committees can become a significant ally in helping the employer to implement and maintain an effective process safety management program for all employees.
3. Process Safety Information. Complete and accurate written information concerning process chemicals, process technology, and process equipment is essential to an effective process safety management program and to a process hazards analysis. The compiled information will be a necessary resource to a variety of users including the team that will perform the process hazards analysis as required under paragraph (e); those developing the training programs and the operating procedures; contractors whose employees will be working with the process; those conducting the pre-startup reviews; local emergency preparedness planners; and insurance and enforcement officials.
The information to be compiled about the chemicals, including process intermediates, needs to be comprehensive enough for an accurate assessment of the fire and explosion characteristics, reactivity hazards, the safety and health hazards to workers, and the corrosion and erosion effects on the process equipment and monitoring tools. Current safety data sheet (SDS) information can be used to help meet this requirement which must be supplemented with process chemistry information including runaway reaction and over pressure hazards if applicable.
Process technology information will be a part of the process safety information package and it is expected that it will include diagrams of the type shown in appendix B of this section as well as employer established criteria for maximum inventory levels for process chemicals; limits beyond which would be considered upset conditions; and a qualitative estimate of the consequences or results of deviation that could occur if operating beyond the established process limits. Employers are encouraged to use diagrams which will help users understand the process.
A block flow diagram is used to show the major process equipment and interconnecting process flow lines and show flow rates, stream composition, temperatures, and pressures when necessary for clarity. The block flow diagram is a simplified diagram.
Process flow diagrams are more complex and will show all main flow streams including valves to enhance the understanding of the process, as well as pressures and temperatures on all feed and product lines within all major vessels, in and out of headers and heat exchangers, and points of pressure and temperature control. Also, materials of construction information, pump capacities and pressure heads, compressor horsepower and vessel design pressures and temperatures are shown when necessary for clarity. In addition, major components of control loops are usually shown along with key utilities on process flow diagrams.
Piping and instrument diagrams (P&IDs) may be the more appropriate type of diagrams to show some of the above details and to display the information for the piping designer and engineering staff. The P&IDs are to be used to describe the relationships between equipment and instrumentation as well as other relevant information that will enhance clarity. Computer software programs which do P&IDs or other diagrams useful to the information package, may be used to help meet this requirement.
The information pertaining to process equipment design must be documented. In other words, what were the codes and standards relied on to establish good engineering practice. These codes and standards are published by such organizations as the American Society of Mechanical Engineers, American Petroleum Institute, American National Standards Institute, National Fire Protection Association, American Society for Testing and Materials, National Board of Boiler and Pressure Vessel Inspectors, National Association of Corrosion Engineers, American Society of Exchange Manufacturers Association, and model building code groups.
In addition, various engineering societies issue technical reports which impact process design. For example, the American Institute of Chemical Engineers has published technical reports on topics such as two phase flow for venting devices. This type of technically recognized report would constitute good engineering practice.
For existing equipment designed and constructed many years ago in accordance with the codes and standards available at that time and no longer in general use today, the employer must document which codes and standards were used and that the design and construction along with the testing, inspection and operation are still suitable for the intended use. Where the process technology requires a design which departs from the applicable codes and standards, the employer must document that the design and construction is suitable for the intended purpose.
4. Process Hazard Analysis. A process hazard analysis (PHA), sometimes called a process hazard evaluation, is one of the most important elements of the process safety management program. A PHA is an organized and systematic effort to identify and analyze the significance of potential hazards associated with the processing or handling of highly hazardous chemicals. A PHA provides information which will assist employers and employees in making decisions for improving safety and reducing the consequences of unwanted or unplanned releases of hazardous chemicals. A PHA is directed toward analyzing potential causes and consequences of fires, explosions, releases of toxic or flammable chemicals and major spills of hazardous chemicals. The PHA focuses on equipment, instrumentation, utilities, human actions (routine and nonroutine), and external factors that might impact the process. These considerations assist in determining the hazards and potential failure points or failure modes in a process.
The selection of a PHA methodology or technique will be influenced by many factors including the amount of existing knowledge about the process. Is it a process that has been operated for a long period of time with little or no innovation and extensive experience has been generated with its use? Or, is it a new process or one which has been changed frequently by the inclusion of innovative features? Also, the size and complexity of the process will influence the decision as to the appropriate PHA methodology to use. All PHA methodologies are subject to certain limitations. For example, the checklist methodology works well when the process is very stable and no changes are made, but it is not as effective when the process has undergone extensive change. The checklist may miss the most recent changes and consequently the changes would not be evaluated. Another limitation to be considered concerns the assumptions made by the team or analyst. The PHA is dependent on good judgement and the assumptions made during the study need to be documented and understood by the team and reviewer and kept for a future PHA.
The team conducting the PHA need to understand the methodology that is going to be used. A PHA team can vary in size from two people to a number of people with varied operational and technical backgrounds. Some team members may only be a part of the team for a limited time. The team leader needs to be fully knowledgeable in the proper implementation of the PHA methodology that is to be used and should be impartial in the evaluation. The other full or part time team members need to provide the team with expertise in areas such as process technology, process design, operating procedures and practices, including how the work is actually performed, alarms, emergency procedures, instrumentation, maintenance procedures, both routine and nonroutine tasks, including how the tasks are authorized, procurement of parts and supplies, safety and health, and any other relevant subject as the need dictates. At least one team member must be familiar with the process.
The ideal team will have an intimate knowledge of the standards, codes, specifications and regulations applicable to the process being studied. The selected team members need to be compatible and the team leader needs to be able to manage the team, and the PHA study. The team needs to be able to work together while benefiting from the expertise of others on the team or outside the team, to resolve issues, and to forge a consensus on the findings of the study and recommendations.
The application of a PHA to a process may involve the use of different methodologies for various parts of the process. For example, a process involving a series of unit operation of varying sizes, complexities, and ages may use different methodologies and team members for each operation. Then the conclusions can be integrated into one final study and evaluation. A more specific example is the use of a checklist PHA for a standard boiler or heat exchanger and the use of a Hazard and Operability PHA for the overall process. Also, for batch type processes like custom batch operations, a generic PHA of a representative batch may be used where there are only small changes of monomer or other ingredient ratios and the chemistry is documented for the full range and ratio of batch ingredients. Another process that might consider using a generic type of PHA is a gas plant. Often these plants are simply moved from site to site and therefore, a generic PHA may be used for these movable plants. Also, when an employer has several similar size gas plants and no sour gas is being processed at the site, then a generic PHA is feasible as long as the variations of the individual sites are accounted for in the PHA. Finally, when an employer has a large continuous process which has several control rooms for different portions of the process such as for a distillation tower and a blending operation, the employer may wish to do each segment separately and then integrate the final results.
Additionally, small businesses which are covered by this rule, will often have processes that have less storage volume, less capacity, and less complicated than processes at a large facility. Therefore, OSHA would anticipate that the less complex methodologies would be used to meet the process hazard analysis criteria in the standard. These process hazard analyses can be done in less time and with a few people being involved. A less complex process generally means that less data, P&IDs, and process information is needed to perform a process hazard analysis.
Many small businesses have processes that are not unique, such as cold storage lockers or water treatment facilities. Where employer associations have a number of members with such facilities, a generic PHA, evolved from a checklist or what-if questions, could be developed and used by each employer effectively to reflect his/her particular process; this would simplify compliance for them.
When the employer has a number of processes which require a PHA, the employer must set up a priority system of which PHAs to conduct first. A preliminary or gross hazard analysis may be useful in prioritizing the processes that the employer has determined are subject to coverage by the process safety management standard. Consideration should first be given to those processes with the potential of adversely affecting the largest number of employees. This prioritizing should consider the potential severity of a chemical release, the number of potentially affected employees, the operating history of the process such as the frequency of chemical releases, the age of the process and any other relevant factors. These factors would suggest a ranking order and would suggest either using a weighing factor system or a systematic ranking method. The use of a preliminary hazard analysis would assist an employer in determining which process should be of the highest priority and thereby the employer would obtain the greatest improvement in safety at the facility.
Detailed guidance on the content and application of process hazard analysis methodologies is available from the American Institute of Chemical Engineers' Center for Chemical Process Safety (see appendix D).
5. Operating Procedures and Practices. Operating procedures describe tasks to be performed, data to be recorded, operating conditions to be maintained, samples to be collected, and safety and health precautions to be taken. The procedures need to be technically accurate, understandable to employees, and revised periodically to ensure that they reflect current operations. The process safety information package is to be used as a resource to better assure that the operating procedures and practices are consistent with the known hazards of the chemicals in the process and that the operating parameters are accurate. Operating procedures should be reviewed by engineering staff and operating personnel to ensure that they are accurate and provide practical instructions on how to actually carry out job duties safely.
Operating procedures will include specific instructions or details on what steps are to be taken or followed in carrying out the stated procedures. These operating instructions for each procedure should include the applicable safety precautions and should contain appropriate information on safety implications. For example, the operating procedures addressing operating parameters will contain operating instructions about pressure limits, temperature ranges, flow rates, what to do when an upset condition occurs, what alarms and instruments are pertinent if an upset condition occurs, and other subjects. Another example of using operating instructions to properly implement operating procedures is in starting up or shutting down the process. In these cases, different parameters will be required from those of normal operation. These operating instructions need to clearly indicate the distinctions between startup and normal operations such as the appropriate allowances for heating up a unit to reach the normal operating parameters. Also the operating instructions need to describe the proper method for increasing the temperature of the unit until the normal operating temperature parameters are achieved.
Computerized process control systems add complexity to operating instructions. These operating instructions need to describe the logic of the software as well as the relationship between the equipment and the control system; otherwise, it may not be apparent to the operator.
Operating procedures and instructions are important for training operating personnel. The operating procedures are often viewed as the standard operating practices (SOPs) for operations. Control room personnel and operating staff, in general, need to have a full understanding of operating procedures. If workers are not fluent in English then procedures and instructions need to be prepared in a second language understood by the workers. In addition, operating procedures need to be changed when there is a change in the process as a result of the management of change procedures. The consequences of operating procedure changes need to be fully evaluated and the information conveyed to the personnel. For example, mechanical changes to the process made by the maintenance department (like changing a valve from steel to brass or other subtle changes) need to be evaluated to determine if operating procedures and practices also need to be changed. All management of change actions must be coordinated and integrated with current operating procedures and operating personnel must be oriented to the changes in procedures before the change is made. When the process is shut down in order to make a change, then the operating procedures must be updated before startup of the process.
Training in how to handle upset conditions must be accomplished as well as what operating personnel are to do in emergencies such as when a pump seal fails or a pipeline ruptures. Communication between operating personnel and workers performing work within the process area, such as nonroutine tasks, also must be maintained. The hazards of the tasks are to be conveyed to operating personnel in accordance with established procedures and to those performing the actual tasks. When the work is completed, operating personnel should be informed to provide closure on the job.
6. Employee Training. All employees, including maintenance and contractor employees, involved with highly hazardous chemicals need to fully understand the safety and health hazards of the chemicals and processes they work with for the protection of themselves, their fellow employees and the citizens of nearby communities. Training conducted in compliance with § 1910.1200, the Hazard Communication standard, will help employees to be more knowledgeable about the chemicals they work with as well as familiarize them with reading and understanding SDSs. However, additional training in subjects such as operating procedures and safety work practices, emergency evacuation and response, safety procedures, routine and nonroutine work authorization activities, and other areas pertinent to process safety and health will need to be covered by an employer's training program.
In establishing their training programs, employers must clearly define the employees to be trained and what subjects are to be covered in their training. Employers in setting up their training program will need to clearly establish the goals and objectives they wish to achieve with the training that they provide to their employees. The learning goals or objectives should be written in clear measurable terms before the training begins. These goals and objectives need to be tailored to each of the specific training modules or segments. Employers should describe the important actions and conditions under which the employee will demonstrate competence or knowledge as well as what is acceptable performance.
Hands-on-training where employees are able to use their senses beyond listening, will enhance learning. For example, operating personnel, who will work in a control room or at control panels, would benefit by being trained at a simulated control panel or panels. Upset conditions of various types could be displayed on the simulator, and then the employee could go through the proper operating procedures to bring the simulator panel back to the normal operating parameters. A training environment could be created to help the trainee feel the full reality of the situation but, of course, under controlled conditions. This realistic type of training can be very effective in teaching employees correct procedures while allowing them to also see the consequences of what might happen if they do not follow established operating procedures. Other training techniques using videos or on-the-job training can also be very effective for teaching other job tasks, duties, or other important information. An effective training program will allow the employee to fully participate in the training process and to practice their skill or knowledge.
Employers need to periodically evaluate their training programs to see if the necessary skills, knowledge, and routines are being properly understood and implemented by their trained employees. The means or methods for evaluating the training should be developed along with the training program goals and objectives. Training program evaluation will help employers to determine the amount of training their employees understood, and whether the desired results were obtained. If, after the evaluation, it appears that the trained employees are not at the level of knowledge and skill that was expected, the employer will need to revise the training program, provide retraining, or provide more frequent refresher training sessions until the deficiency is resolved. Those who conducted the training and those who received the training should also be consulted as to how best to improve the training process. If there is a language barrier, the language known to the trainees should be used to reinforce the training messages and information.
Careful consideration must be given to assure that employees including maintenance and contract employees receive current and updated training. For example, if changes are made to a process, impacted employees must be trained in the changes and understand the effects of the changes on their job tasks (e.g., any new operating procedures pertinent to their tasks). Additionally, as already discussed the evaluation of the employee's absorption of training will certainly influence the need for training.
7. Contractors. Employers who use contractors to perform work in and around processes that involve highly hazardous chemicals, will need to establish a screening process so that they hire and use contractors who accomplish the desired job tasks without compromising the safety and health of employees at a facility. For contractors, whose safety performance on the job is not known to the hiring employer, the employer will need to obtain information on injury and illness rates and experience and should obtain contractor references. Additionally, the employer must assure that the contractor has the appropriate job skills, knowledge and certifications (such as for pressure vessel welders). Contractor work methods and experiences should be evaluated. For example, does the contractor conducting demolition work swing loads over operating processes or does the contractor avoid such hazards?
Maintaining a site injury and illness log for contractors is another method employers must use to track and maintain current knowledge of work activities involving contract employees working on or adjacent to covered processes. Injury and illness logs of both the employer's employees and contract employees allow an employer to have full knowledge of process injury and illness experience. This log will also contain information which will be of use to those auditing process safety management compliance and those involved in incident investigations.
Contract employees must perform their work safely. Considering that contractors often perform very specialized and potentially hazardous tasks such as confined space entry activities and nonroutine repair activities it is quite important that their activities be controlled while they are working on or near a covered process. A permit system or work authorization system for these activities would also be helpful to all affected employers. The use of a work authorization system keeps an employer informed of contract employee activities, and as a benefit the employer will have better coordination and more management control over the work being performed in the process area. A well run and well maintained process where employee safety is fully recognized will benefit all of those who work in the facility whether they be contract employees or employees of the owner.
8. Pre-Startup Safety. For new processes, the employer will find a PHA helpful in improving the design and construction of the process from a reliability and quality point of view. The safe operation of the new process will be enhanced by making use of the PHA recommendations before final installations are completed. P&IDs are to be completed along with having the operating procedures in place and the operating staff trained to run the process before startup. The initial startup procedures and normal operating procedures need to be fully evaluated as part of the pre-startup review to assure a safe transfer into the normal operating mode for meeting the process parameters.
For existing processes that have been shutdown for turnaround, or modification, etc., the employer must assure that any changes other than “replacement in kind” made to the process during shutdown go through the management of change procedures. P&IDs will need to be updated as necessary, as well as operating procedures and instructions. If the changes made to the process during shutdown are significant and impact the training program, then operating personnel as well as employees engaged in routine and nonroutine work in the process area may need some refresher or additional training in light of the changes. Any incident investigation recommendations, compliance audits or PHA recommendations need to be reviewed as well to see what impacts they may have on the process before beginning the startup.
9. Mechanical Integrity. Employers will need to review their maintenance programs and schedules to see if there are areas where “breakdown” maintenance is used rather than an on-going mechanical integrity program. Equipment used to process, store, or handle highly hazardous chemicals needs to be designed, constructed, installed and maintained to minimize the risk of releases of such chemicals. This requires that a mechanical integrity program be in place to assure the continued integrity of process equipment. Elements of a mechanical integrity program include the identification and categorization of equipment and instrumentation, inspections and tests, testing and inspection frequencies, development of maintenance procedures, training of maintenance personnel, the establishment of criteria for acceptable test results, documentation of test and inspection results, and documentation of manufacturer recommendations as to meantime to failure for equipment and instrumentation.
The first line of defense an employer has available is to operate and maintain the process as designed, and to keep the chemicals contained. This line of defense is backed up by the next line of defense which is the controlled release of chemicals through venting to scrubbers or flares, or to surge or overflow tanks which are designed to receive such chemicals, etc. These lines of defense are the primary lines of defense or means to prevent unwanted releases. The secondary lines of defense would include fixed fire protection systems like sprinklers, water spray, or deluge systems, monitor guns, etc., dikes, designed drainage systems, and other systems which would control or mitigate hazardous chemicals once an unwanted release occurs. These primary and secondary lines of defense are what the mechanical integrity program needs to protect and strengthen these primary and secondary lines of defenses where appropriate.
The first step of an effective mechanical integrity program is to compile and categorize a list of process equipment and instrumentation for inclusion in the program. This list would include pressure vessels, storage tanks, process piping, relief and vent systems, fire protection system components, emergency shutdown systems and alarms and interlocks and pumps. For the categorization of instrumentation and the listed equipment the employer would prioritize which pieces of equipment require closer scrutiny than others. Meantime to failure of various instrumentation and equipment parts would be known from the manufacturers data or the employer's experience with the parts, which would then influence the inspection and testing frequency and associated procedures. Also, applicable codes and standards such as the National Board Inspection Code, or those from the American Society for Testing and Material, American Petroleum Institute, National Fire Protection Association, American National Standards Institute, American Society of Mechanical Engineers, and other groups, provide information to help establish an effective testing and inspection frequency, as well as appropriate methodologies.
The applicable codes and standards provide criteria for external inspections for such items as foundation and supports, anchor bolts, concrete or steel supports, guy wires, nozzles and sprinklers, pipe hangers, grounding connections, protective coatings and insulation, and external metal surfaces of piping and vessels, etc. These codes and standards also provide information on methodologies for internal inspection, and a frequency formula based on the corrosion rate of the materials of construction. Also, erosion both internal and external needs to be considered along with corrosion effects for piping and valves. Where the corrosion rate is not known, a maximum inspection frequency is recommended, and methods of developing the corrosion rate are available in the codes. Internal inspections need to cover items such as vessel shell, bottom and head; metallic linings; nonmetallic linings; thickness measurements for vessels and piping; inspection for erosion, corrosion, cracking and bulges; internal equipment like trays, baffles, sensors and screens for erosion, corrosion or cracking and other deficiencies. Some of these inspections may be performed by state of local government inspectors under state and local statutes. However, each employer needs to develop procedures to ensure that tests and inspections are conducted properly and that consistency is maintained even where different employees may be involved. Appropriate training is to be provided to maintenance personnel to ensure that they understand the preventive maintenance program procedures, safe practices, and the proper use amd application of special equipment or unique tools that may be required. This training is part of the overall training program called for in the standard.
A quality assurance system is needed to help ensure that the proper materials of construction are used, that fabrication and inspection procedures are proper, and that installation procedures recognize field installation concerns. The quality assurance program is an essential part of the mechanical integrity program and will help to maintain the primary and secondary lines of defense that have been designed into the process to prevent unwanted chemical releases or those which control or mitigate a release. “As built” drawings, together with certifications of coded vessels and other equipment, and materials of construction need to be verified and retained in the quality assurance documentation. Equipment installation jobs need to be properly inspected in the field for use of proper materials and procedures and to assure that qualified craftsmen are used to do the job. The use of appropriate gaskets, packing, bolts, valves, lubricants and welding rods need to be verified in the field. Also procedures for installation of safety devices need to be verified, such as the torque on the bolts on ruptured disc installations, uniform torque on flange bolts, proper installation of pump seals, etc. If the quality of parts is a problem, it may be appropriate to conduct audits of the equipment supplier's facilities to better assure proper purchases of required equipment which is suitable for its intended service. Any changes in equipment that may become necessary will need to go through the management of change procedures.
10. Nonroutine Work Authorizations. Nonroutine work which is conducted in process areas needs to be controlled by the employer in a consistent manner. The hazards identified involving the work that is to be accomplished must be communicated to those doing the work, but also to those operating personnel whose work could affect the safety of the process. A work authorization notice or permit must have a procedure that describes the steps the maintenance supervisor, contractor representative or other person needs to follow to obtain the necessary clearance to get the job started. The work authorization procedures need to reference and coordinate, as applicable, lockout/tagout procedures, line breaking procedures, confined space entry procedures and hot work authorizations. This procedure also needs to provide clear steps to follow once the job is completed in order to provide closure for those that need to know the job is now completed and equipment can be returned to normal.
11. Managing Change. To properly manage changes to process chemicals, technology, equipment and facilities, one must define what is meant by change. In this process safety management standard, change includes all modifications to equipment, procedures, raw materials and processing conditions other than “replacement in kind”. These changes need to be properly managed by identifying and reviewing them prior to implementation of the change. For example, the operating procedures contain the operating parameters (pressure limits, temperature ranges, flow rates, etc.) and the importance of operating within these limits. While the operator must have the flexibility to maintain safe operation within the established parameters, any operation outside of these parameters requires review and approval by a written management of change procedure.
Management of change covers such as changes in process technology and changes to equipment and instrumentation. Changes in process technology can result from changes in production rates, raw materials, experimentation, equipment unavailability, new equipment, new product development, change in catalyst and changes in operating conditions to improve yield or quality. Equipment changes include among others change in materials of construction, equipment specifications, piping pre-arrangements, experimental equipment, computer program revisions and changes in alarms and interlocks. Employers need to establish means and methods to detect both technical changes and mechanical changes.
Temporary changes have caused a number of catastrophes over the years, and employers need to establish ways to detect temporary changes as well as those that are permanent. It is important that a time limit for temporary changes be established and monitored since, without control, these changes may tend to become permanent. Temporary changes are subject to the management of change provisions. In addition, the management of change procedures are used to insure that the equipment and procedures are returned to their original or designed conditions at the end of the temporary change. Proper documentation and review of these changes is invaluable in assuring that the safety and health considerations are being incorporated into the operating procedures and the process.
Employers may wish to develop a form or clearance sheet to facilitate the processing of changes through the management of change procedures. A typical change form may include a description and the purpose of the change, the technical basis for the change, safety and health considerations, documentation of changes for the operating procedures, maintenance procedures, inspection and testing, P&IDs, electrical classification, training and communications, pre-startup inspection, duration if a temporary change, approvals and authorization. Where the impact of the change is minor and well understood, a check list reviewed by an authorized person with proper communication to others who are affected may be sufficient. However, for a more complex or significant design change, a hazard evaluation procedure with approvals by operations, maintenance, and safety departments may be appropriate. Changes in documents such as P&IDs, raw materials, operating procedures, mechanical integrity programs, electrical classifications, etc., need to be noted so that these revisions can be made permanent when the drawings and procedure manuals are updated. Copies of process changes need to be kept in an accessible location to ensure that design changes are available to operating personnel as well as to PHA team members when a PHA is being done or one is being updated.
12. Investigation of Incidents. Incident investigation is the process of identifying the underlying causes of incidents and implementing steps to prevent similar events from occurring. The intent of an incident investigation is for employers to learn from past experiences and thus avoid repeating past mistakes. The incidents for whicn OSHA expects employers to become aware and to investigate are the types of events which result in or could reasonably have resulted in a catastrophic release. Some of the events are sometimes referred to as “near misses,” meaning that a serious consequence did not occur, but could have.
Employers need to develop in-house capability to investigate incidents that occur in their facilities. A team needs to be assembled by the employer and trained in the techniques of investigation including how to conduct interviews of witnesses, needed documentation and report writing. A multi-disciplinary team is better able to gather the facts of the event and to analyze them and develop plausible scenarios as to what happened, and why. Team members should be selected on the basis of their training, knowledge and ability to contribute to a team effort to fully investigate the incident. Employees in the process area where the incident occurred should be consulted, interviewed or made a member of the team. Their knowledge of the events form a significant set of facts about the incident which occurred. The report, its findings and recommendations are to be shared with those who can benefit from the information. The cooperation of employees is essential to an effective incident investigation. The focus of the investigation should be to obtain facts, and not to place blame. The team and the investigation process should clearly deal with all involved individuals in a fair, open and consistent manner.
13. Emergency Preparedness. Each employer must address what actions employees are to take when there is an unwanted release of highly hazardous chemicals. Emergency preparedness or the employer's tertiary (third) lines of defense are those that will be relied on along with the secondary lines of defense when the primary lines of defense which are used to prevent an unwanted release fail to stop the release. Employers will need to decide if they want employees to handle and stop small or minor incidental releases. Whether they wish to mobilize the available resources at the plant and have them brought to bear on a more significant release. Or whether employers want their employees to evacuate the danger area and promptly escape to a preplanned safe zone area, and allow the local community emergency response organizations to handle the release. Or whether the employer wants to use some combination of these actions. Employers will need to select how many different emergency preparedness or tertiary lines of defense they plan to have and then develop the necessary plans and procedures, and appropriately train employees in their emergency duties and responsibilities and then implement these lines of defense.
Employers at a minimum must have an emergency action plan which will facilitate the prompt evacuation of employees due to an unwanted release of a highly hazardous chemical. This means that the employer will have a plan that will be activated by an alarm system to alert employees when to evacuate and, that employees who are physically impaired, will have the necessary support and assistance to get them to the safe zone as well. The intent of these requirements is to alert and move employees to a safe zone quickly. Delaying alarms or confusing alarms are to be avoided. The use of process control centers or similar process buildings in the process area as safe areas is discouraged. Recent catastrophes have shown that a large life loss has occurred in these structures because of where they have been sited and because they are not necessarily designed to withstand over-pressures from shockwaves resulting from explosions in the process area.
Unwanted incidental releases of highly hazardous chemicals in the process area must be addressed by the employer as to what actions employees are to take. If the employer wants employees to evacuate the area, then the emergency action plan will be activated. For outdoor processes where wind direction is important for selecting the safe route to a refuge area, the employer should place a wind direction indicator such as a wind sock or pennant at the highest point that can be seen throughout the process area. Employees can move in the direction of cross wind to upwind to gain safe access to the refuge area by knowing the wind direction.
If the employer wants specific employees in the release area to control or stop the minor emergency or incidental release, these actions must be planned for in advance and procedures developed and implemented. Preplanning for handling incidental releases for minor emergencies in the process area needs to be done, appropriate equipment for the hazards must be provided, and training conducted for those employees who will perform the emergency work before they respond to handle an actual release. The employer's training program, including the Hazard Communication standard training is to address the training needs for employees who are expected to handle incidental or minor releases.
Preplanning for releases that are more serious than incidental releases is another important line of defense to be used by the employer. When a serious release of a highly hazardous chemical occurs, the employer through preplanning will have determined in advance what actions employees are to take. The evacuation of the immediate release area and other areas as necessary would be accomplished under the emergency action plan. If the employer wishes to use plant personnel such as a fire brigade, spill control team, a hazardous materials team, or use employees to render aid to those in the immediate release area and control or mitigate the incident, these actions are covered by § 1910.120, the Hazardous Waste Operations and Emergency Response (HAZWOPER) standard. If outside assistance is necessary, such as through mutual aid agreements between employers or local government emergency response organizations, these emergency responders are also covered by HAZWOPER. The safety and health protections required for emergency responders are the responsibility of their employers and of the on-scene incident commander.
Responders may be working under very hazardous conditions and therefore the objective is to have them competently led by an on-scene incident commander and the commander's staff, properly equipped to do their assigned work safely, and fully trained to carry out their duties safely before they respond to an emergency. Drills, training exercises, or simulations with the local community emergency response planners and responder organizations is one means to obtain better preparedness. This close cooperation and coordination between plant and local community emergency preparedness managers will also aid the employer in complying with the Environmental Protection Agency's Risk Management Plan criteria.
One effective way for medium to large facilities to enhance coordination and communication during emergencies for on plant operations and with local community organizations is for employers to establish and equip an emergency control center. The emergency control center would be sited in a safe zone area so that it could be occupied throughout the duration of an emergency. The center would serve as the major ccommunication link between the on-scene incident commander and plant or corporate management as well as with the local community officials. The communication equipment in the emergency control center should include a network to receive and transmit information by telephone, radio or other means. It is important to have a backup communication network in case of power failure or one communication means fails. The center should also be equipped with the plant layout and community maps, utility drawings including fire water, emergency lighting, appropriate reference materials such as a government agency notification list, company personnel phone list, SARA Title III reports and safety data sheets, emergency plans and procedures manual, a listing with the location of emergency response equipment, mutual aid information, and access to meteorological or weather condition data and any dispersion modeling data.
14. Compliance Audits. Employers need to select a trained individual or assemble a trained team of people to audit the process safety management system and program. A small process or plant may need only one knowledgeable person to conduct an audit. The audit is to include an evaluation of the design and effectiveness of the process safety management system and a field inspection of the safety and health conditions and practices to verify that the employer's systems are effectively implemented. The audit should be conducted or lead by a person knowledgeable in audit techniques and who is impartial towards the facility or area being audited. The essential elements of an audit program include planning, staffing, conduting the audit, evaluation and corrective action, follow-up and documentation.
Planning in advance is essential to the success of the auditing process. Each employer needs to establish the format, staffing, scheduling and verification methods prior to conducting the audit. The format should be designed to provide the lead auditor with a procedure or checklist which details the requirements of each section of the standard. The names of the audit team members should be listed as part of the format as well. The checklist, if properly designed, could serve as the verification sheet which provides the auditor with the necessary information to expedite the review and assure that no requirements of the standard are omitted. This verification sheet format could also identify those elements that will require evaluation or a response to correct deficiencies. This sheet could also be used for developing the follow-up and documentation requirements.
The selection of effective audit team members is critical to the success of the program. Team members should be chosen for their experience, knowledge, and training and should be familiar with the processes and with auditing techniques, practices and procedures. The size of the team will vary depending on the size and complexity of the process under consideration. For a large, complex, highly instrumented plant, it may be desirable to have team members with expertise in process engineering and design, process chemistry, instrumentation and computer controls, electrical hazards and classifications, safety and health disciplines, maintenance, emergency preparedness, warehousing or shipping, and process safety auditing. The team may use part-time members to provide for the depth of expertise required as well as for what is actually done or followed, compared to what is written.
An effective audit includes a review of the relevant documentation and process safety information, inspection of the physical facilities, and interviews with all levels of plant personnel. Utilizing the audit procedure and checklist developed in the preplanning stage, the audit team can systematically analyze compliance with the provisions of the standard and any other corporate policies that are relevant. For example, the audit team will review all aspects of the training program as part of the overall audit. The team will review the written training program for adequacy of content, frequency of training, effectiveness of training in terms of its goals and objectives as well as to how it fits into meeting the standard's requirements, documentation, etc. Through interviews, the team can determine the employee's knowledge and awareness of the safety procedures, duties, rules, emergency response assignments, etc. During the inspection, the team can observe actual practices such as safety and health policies, procedures, and work authorization practices. This approach enables the team to identify deficiencies and determine where corrective actions or improvements are necessary.
An audit is a technique used to gather sufficient facts and information, including statistical information, to verify compliance with standards. Auditors should select as part of their preplanning a sample size sufficient to give a degree of confidence that the audit reflects the level of compliance with the standard. The audit team, through this systematic analysis, should document areas which require corrective action as well as those areas where the process safety management system is effective and working in an effective manner. This provides a record of the audit procedures and findings, and serves as a baseline of operation data for future audits. It will assist future auditors in determining changes or trends from previous audits.
Corrective action is one of the most important parts of the audit. It includes not only addressing the identified deficiencies, but also planning, followup, and documentation. The corrective action process normally begins with a management review of the audit findings. The purpose of this review is to determine what actions are appropriate, and to establish priorities, timetables, resource allocations and requirements and responsibilities. In some cases, corrective action may involve a simple change in procedure or minor maintenance effort to remedy the concern. Management of change procedures need to be used, as appropriate, even for what may seem to be a minor change. Many of the deficiencies can be acted on promptly, while some may require engineering studies or indepth review of actual procedures and practices. There may be instances where no action is necessary and this is a valid response to an audit finding. All actions taken, including an explanation where no action is taken on a finding, needs to be documented as to what was done and why.
It is important to assure that each deficiency identified is addressed, the corrective action to be taken noted, and the audit person or team responsible be properly documented by the employer. To control the corrective action process, the employer should consider the use of a tracking system. This tracking system might include periodic status reports shared with affected levels of management, specific reports such as completion of an engineering study, and a final implementation report to provide closure for audit findings that have been through management of change, if appropriate, and then shared with affected employees and management. This type of tracking system provides the employer with the status of the corrective action. It also provides the documentation required to verify that appropriate corrective actions were taken on deficiencies identified in the audit.
Appendix D to § 1910.119—Sources of Further Information (Nonmandatory)
1. Center for Chemical Process Safety, American Institute of Chemical Engineers, 345 East 47th Street, New York, NY 10017, (212) 705-7319.
2. “Guidelines for Hazard Evaluation Procedures,” American Institute of Chemical Engineers; 345 East 47th Street, New York, NY 10017.
3. “Guidelines for Technical Management of Chemical Process Safety,” Center for Chemical Process Safety of the American Institute of Chemical Engineers; 345 East 47th Street, New York, NY 10017.
4. “Evaluating Process Safety in the Chemical Industry,” Chemical Manufacturers Association; 2501 M Street NW, Washington, DC 20037.
5. “Safe Warehousing of Chemicals,” Chemical Manufacturers Association; 2501 M Street NW, Washington, DC 20037.
6. “Management of Process Hazards,” American Petroleum Institute (API Recommended Practice 750); 1220 L Street, N.W., Washington, D.C. 20005.
7. “Improving Owner and Contractor Safety Performance,” American Petroleum Institute (API Recommended Practice 2220); API, 1220 L Street N.W., Washington, D.C. 20005.
8. Chemical Manufacturers Association (CMA's Manager Guide), First Edition, September 1991; CMA, 2501 M Street, N.W., Washington, D.C. 20037.
9. “Improving Construction Safety Performance,” Report A-3, The Business Roundtable; The Business Roundtable, 200 Park Avenue, New York, NY 10166. (Report includes criteria to evaluate contractor safety performance and criteria to enhance contractor safety performance).
10. “Recommended Guidelines for Contractor Safety and Health,” Texas Chemical Council; Texas Chemical Council, 1402 Nueces Street, Austin, TX 78701-1534.
11. “Loss Prevention in the Process Industries,” Volumes I and II; Frank P. Lees, Butterworth; London 1983.
12. “Safety and Health Program Management Guidelines,” 1989; U.S. Department of Labor, Occupational Safety and Health Administration.
13. “Safety and Health Guide for the Chemical Industry,” 1986, (OSHA 3091); U.S. Department of Labor, Occupational Safety and Health Administration; 200 Constitution Avenue, N.W., Washington, D.C. 20210.
14. “Review of Emergency Systems,” June 1988; U.S. Environmental Protection Agency (EPA), Office of Solid Waste and Emergency Response, Washington, DC 20460.
15. “Technical Guidance for Hazards Analysis, Emergency Planning for Extremely Hazardous Substances,” December 1987; U.S. Environmental Protection Agency (EPA), Federal Emergency Management Administration (FEMA) and U.S. Department of Transportation (DOT), Washington, DC 20460.
16. “Accident Investigation * * * A New Approach,” 1983, National Safety Council; 444 North Michigan Avenue, Chicago, IL 60611-3991.
17. “Fire & Explosion Index Hazard Classification Guide,” 6th Edition, May 1987, Dow Chemical Company; Midland, Michigan 48674.
18. “Chemical Exposure Index,” May 1988, Dow Chemical Company; Midland, Michigan 48674.
[57 FR 6403, Feb. 24, 1992; 57 FR 7847, Mar. 4, 1992, as amended at 61 FR 9238, Mar. 7, 1996; 67 FR 67964, Nov. 7, 2002; 76 FR 80738, Dec. 27, 2011; 77 FR 17776, Mar. 26, 2012; 78 FR 9313, Feb. 8, 2013; 84 FR 15102, Apr. 15, 2019]
This section covers the following operations, unless the employer can demonstrate that the operation does not involve employee exposure or the reasonable possibility for employee exposure to safety or health hazards:
Clean-up operation means an operation where hazardous substances are removed, contained, incinerated, neutralized, stabilized, cleared-up, or in any other manner processed or handled with the ultimate goal of making the site safer for people or the environment.
Decontamination means the removal of hazardous substances from employees and their equipment to the extent necessary to preclude the occurrence of foreseeable adverse health affects.
Emergency response or responding to emergencies means a response effort by employees from outside the immediate release area or by other designated responders (i.e., mutual-aid groups, local fire departments, etc.) to an occurrence which results, or is likely to result, in an uncontrolled release of a hazardous substance. Responses to incidental releases of hazardous substances where the substance can be absorbed, neutralized, or otherwise controlled at the time of release by employees in the immediate release area, or by maintenance personnel are not considered to be emergency responses within the scope of this standard. Responses to releases of hazardous substances where there is no potential safety or health hazard (i.e., fire, explosion, or chemical exposure) are not considered to be emergency responses.
Facility means (A) any building, structure, installation, equipment, pipe or pipeline (including any pipe into a sewer or publicly owned treatment works), well, pit, pond, lagoon, impoundment, ditch, storage container, motor vehicle, rolling stock, or aircraft, or (B) any site or area where a hazardous substance has been deposited, stored, disposed of, or placed, or otherwise come to be located; but does not include any consumer product in consumer use or any water-borne vessel.
Hazardous materials response (HAZMAT) team means an organized group of employees, designated by the employer, who are expected to perform work to handle and control actual or potential leaks or spills of hazardous substances requiring possible close approach to the substance. The team members perform responses to releases or potential releases of hazardous substances for the purpose of control or stabilization of the incident. A HAZMAT team is not a fire brigade nor is a typical fire brigade a HAZMAT team. A HAZMAT team, however, may be a separate component of a fire brigade or fire department.
Hazardous substance means any substance designated or listed under paragraphs (A) through (D) of this definition, exposure to which results or may result in adverse affects on the health or safety of employees:
Department of Transportation as hazardous materials under 49 CFR 172.101 and appendices; and
Hazardous waste means—
Hazardous waste operation means any operation conducted within the scope of this standard.
Hazardous waste site or Site means any facility or location within the scope of this standard at which hazardous waste operations take place.
Health hazard means a chemical or a pathogen where acute or chronic health effects may occur in exposed employees. It also includes stress due to temperature extremes. The term health hazard includes chemicals that are classified in accordance with the Hazard Communication Standard, 29 CFR 1910.1200, as posing one of the following hazardous effects: Acute toxicity (any route of exposure); skin corrosion or irritation; serious eye damage or eye irritation; respiratory or skin sensitization; germ cell mutagenicity; carcinogenicity; reproductive toxicity; specific target organ toxicity (single or repeated exposure); aspiration toxicity or simple asphyxiant. ( See Appendix A to § 1910.1200—Health Hazard Criteria (Mandatory) for the criteria for determining whether a chemical is classified as a health hazard.)
IDLH or Immediately dangerous to life or health means an atmospheric concentration of any toxic, corrosive or asphyxiant substance that poses an immediate threat to life or would cause irreversible or delayed adverse health effects or would interfere with an individual's ability to escape from a dangerous atmosphere.
Oxygen deficiency means that concentration of oxygen by volume below which atmosphere supplying respiratory protection must be provided. It exists in atmospheres where the percentage of oxygen by volume is less than 19.5 percent oxygen.
Permissible exposure limit means the exposure, inhalation or dermal permissible exposure limit specified in 29 CFR part 1910, subparts G and Z.
Published exposure level means the exposure limits published in “NIOSH Recommendations for Occupational Health Standards” dated 1986, which is incorporated by reference as specified in § 1910.6 or if none is specified, the exposure limits published in the standards specified by the American Conference of Governmental Industrial Hygienists in their publication “Threshold Limit Values and Biological Exposure Indices for 1987-88” dated 1987, which is incorporated by reference as specified in § 1910.6.
Post emergency response means that portion of an emergency response performed after the immediate threat of a release has been stabilized or eliminated and clean-up of the site has begun. If post emergency response is performed by an employer's own employees who were part of the initial emergency response, it is considered to be part of the initial response and not post emergency response. However, if a group of an employer's own employees, separate from the group providing initial response, performs the clean-up operation, then the separate group of employees would be considered to be performing post-emergency response and subject to paragraph (q)(11) of this section.
Qualified person means a person with specific training, knowledge and experience in the area for which the person has the responsibility and the authority to control.
Site safety and health supervisor (or official) means the individual located on a hazardous waste site who is responsible to the employer and has the authority and knowledge necessary to implement the site safety and health plan and verify compliance with applicable safety and health requirements.
Small quantity qenerator means a generator of hazardous wastes who in any calendar month generates no more than 1,000 kilograms (2,205 pounds) of hazardous waste in that month.
Uncontrolled hazardous waste site, means an area identified as an uncontrolled hazardous waste site by a governmental body, whether Federal, state, local or other where an accumulation of hazardous substances creates a threat to the health and safety of individuals or the environment or both. Some sites are found on public lands such as those created by former municipal, county or state landfills where illegal or poorly managed waste disposal has taken place. Other sites are found on private property, often belonging to generators or former generators of hazardous substance wastes. Examples of such sites include, but are not limited to, surface impoundments, landfills, dumps, and tank or drum farms. Normal operations at TSD sites are not covered by this definition.
Site excavations created during initial site preparation or during hazardous waste operations shall be shored or sloped as appropriate to prevent accidental collapse in accordance with subpart P of 29 CFR part 1926.
An employer who retains contractor or sub-contractor services for work in hazardous waste operations shall inform those contractors, sub-contractors, or their representatives of the site emergency response procedures and any potential fire, explosion, health, safety or other hazards of the hazardous waste operation that have been identified by the employer, including those identified in the employer's information program.
The written safety and health program shall be made available to any contractor or subcontractor or their representative who will be involved with the hazardous waste operation; to employees; to employee designated representatives; to OSHA personnel, and to personnel of other Federal, state, or local agencies with regulatory authority over the site.
The comprehensive workplan part of the program shall address the tasks and objectives of the site operations and the logistics and resources required to reach those tasks and objectives.
The site safety and health plan, which must be kept on site, shall address the safety and health hazards of each phase of site operation and include the requirements and procedures for employee protection.
The site safety and health plan, as a minimum, shall address the following:
The site specific safety and health plan shall provide for pre-entry briefings to be held prior to initiating any site activity, and at such other times as necessary to ensure that employees are apprised of the site safety and health plan and that this plan is being followed. The information and data obtained from site characterization and analysis work required in paragraph (c) of this section shall be used to prepare and update the site safety and health plan.
Inspections shall be conducted by the site safety and health supervisor or, in the absence of that individual, another individual who is knowledgeable in occupational safety and health, acting on behalf of the employer as necessary to determine the effectiveness of the site safety and health plan. Any deficiencies in the effectiveness of the site safety and health plan shall be corrected by the employer.
Hazardous waste sites shall be evaluated in accordance with this paragraph to identify specific site hazards and to determine the appropriate safety and health control procedures needed to protect employees from the identified hazards.
A preliminary evaluation of a site's characteristics shall be performed prior to site entry by a qualified person in order to aid in the selection of appropriate employee protection methods prior to site entry. Immediately after initial site entry, a more detailed evaluation of the site's specific characteristics shall be performed by a qualified person in order to further identify existing site hazards and to further aid in the selection of the appropriate engineering controls and personal protective equipment for the tasks to be performed.
All suspected conditions that may pose inhalation or skin absorption hazards that are immediately dangerous to life or health (IDLH), or other conditions that may cause death or serious harm, shall be identified during the preliminary survey and evaluated during the detailed survey. Examples of such hazards include, but are not limited to, confined space entry, potentially explosive or flammable situations, visible vapor clouds, or areas where biological indicators such as dead animals or vegetation are located.
The following information to the extent available shall be obtained by the employer prior to allowing employees to enter a site:
Personal protective equipment (PPE) shall be provided and used during initial site entry in accordance with the following requirements:
The following monitoring shall be conducted during initial site entry when the site evaluation produces information that shows the potential for ionizing radiation or IDLH conditions, or when the site information is not sufficient reasonably to eliminate these possible conditions:
Once the presence and concentrations of specific hazardous substances and health hazards have been established, the risks associated with these substances shall be identified. Employees who will be working on the site shall be informed of any risks that have been identified. In situations covered by the Hazard Communication Standard, 29 CFR 1910.1200, training required by that standard need not be duplicated.
Any information concerning the chemical, physical, and toxicologic properties of each substance known or expected to be present on site that is available to the employer and relevant to the duties an employee is expected to perform shall be made available to the affected employees prior to the commencement of their work activities. The employer may utilize information developed for the hazard communication standard for this purpose.
Appropriate site control procedures shall be implemented to control employee exposure to hazardous substances before clean-up work begins.
A site control program for protecting employees which is part of the employer's site safety and health program required in paragraph (b) of this section shall be developed during the planning stages of a hazardous waste clean-up operation and modified as necessary as new information becomes available.
The site control program shall, as a minimum, include: A site map; site work zones; the use of a “buddy system”; site communications including alerting means for emergencies; the standard operating procedures or safe work practices; and, identification of the nearest medical assistance. Where these requirements are covered elsewhere they need not be repeated.
The training shall thoroughly cover the following:
On-site management and supervisors directly responsible for, or who supervise employees engaged in, hazardous waste operations shall receive 40 hours initial training, and three days of supervised field experience (the training may be reduced to 24 hours and one day if the only area of their responsibility is employees covered by paragraphs (e)(3)(ii) and (e)(3)(iii)) and at least eight additional hours of specialized training at the time of job assignment on such topics as, but not limited to, the employer's safety and health program and the associated employee training program, personal protective equipment program, spill containment program, and health hazard monitoring procedure and techniques.
Trainers shall be qualified to instruct employees about the subject matter that is being presented in training. Such trainers shall have satisfactorily completed a training program for teaching the subjects they are expected to teach, or they shall have the academic credentials and instructional experience necessary for teaching the subjects. Instructors shall demonstrate competent instructional skills and knowledge of the applicable subject matter.
Employees and supervisors that have received and successfully completed the training and field experience specified in paragraphs (e)(1) through (e)(4) of this section shall be certified by their instructor or the head instructor and trained supervisor as having successfully completed the necessary training. A written certificate shall be given to each person so certified. Any person who has not been so certified or who does not meet the requirements of paragraph (e)(9) of this section shall be prohibited from engaging in hazardous waste operations.
Employees who are engaged in responding to hazardous emergency situations at hazardous waste clean-up sites that may expose them to hazardous substances shall be trained in how to respond to such expected emergencies.
Employees specified in paragraph (e)(1) of this section, and managers and supervisors specified in paragraph (e)(4) of this section, shall receive eight hours of refresher training annually on the items specified in paragraph (e)(2) and/or (e)(4) of this section, any critique of incidents that have occurred in the past year that can serve as training examples of related work, and other relevant topics.
Employers who can show by documentation or certification that an employee's work experience and/or training has resulted in training equivalent to that training required in paragraphs (e)(1) through (e)(4) of this section shall not be required to provide the initial training requirements of those paragraphs to such employees and shall provide a copy of the certification or documentation to the employee upon request. However, certified employees or employees with equivalent training new to a site shall receive appropriate, site specific training before site entry and have appropriate supervised field experience at the new site. Equivalent training includes any academic training or the training that existing employees might have already received from actual hazardous waste site work experience.
Employers engaged in operations specified in paragraphs (a)(1)(i) through (a)(1)(iv) of this section and not covered by (a)(2)(iii) exceptions and employers of employees specified in paragraph (q)(9) shall institute a medical surveillance program in accordance with this paragraph.
The medical surveillance program shall be instituted by the employer for the following employees:
Medical examinations and consultations shall be made available by the employer to each employee covered under paragraph (f)(2) of this section on the following schedules:
All medical examinations and procedures shall be performed by or under the supervision of a licensed physician, preferably one knowledgeable in occupational medicine, and shall be provided without cost to the employee, without loss of pay, and at a reasonable time and place.
The employer shall provide one copy of this standard and its appendices to the attending physician, and in addition the following for each employee:
A written personal protective equipment program, which is part of the employer's safety and health program required in paragraph (b) of this section or required in paragraph (p)(1) of this section and which is also a part of the site-specific safety and health plan shall be established. The PPE program shall address the elements listed below. When elements, such as donning and doffing procedures, are provided by the manufacturer of a piece of equipment and are attached to the plan, they need not be rewritten into the plan as long as they adequately address the procedure or element.
selection based upon site hazards,
use and limitations of the equipment,
maintenance and storage,
decontamination and disposal,
training and proper fitting,
donning and doffing procedures,
inspection procedures prior to, during, and after use,
Upon initial entry, representative air monitoring shall be conducted to identify any IDLH condition, exposure over permissible exposure limits or published exposure levels, exposure over a radioactive material's dose limits or other dangerous condition such as the presence of flammable atmospheres or oxygen-deficient environments.
Periodic monitoring shall be conducted when the possibility of an IDLH condition or flammable atmosphere has developed or when there is indication that exposures may have risen over permissible exposure limits or published exposure levels since prior monitoring. Situations where it shall be considered whether the possibility that exposures have risen are as follows:
After the actual clean-up phase of any hazardous waste operation commences; for example, when soil, surface water or containers are moved or disturbed; the employer shall monitor those employees likely to have the highest exposures to hazardous substances and health hazards likely to be present above permissible exposure limits or published exposure levels by using personal sampling frequently enough to characterize employee exposures. If the employees likely to have the highest exposure are over permissible exposure limits or published exposure limits, then monitoring shall continue to determine all employees likely to be above those limits. The employer may utilize a representative sampling approach by documenting that the employees and chemicals chosen for monitoring are based on the criteria stated above.
Employers shall develop and implement a program, which is part of the employer's safety and health program required in paragraph (b) of this section, to inform employees, contractors, and subcontractors (or their representative) actually engaged in hazardous waste operations of the nature, level and degree of exposure likely as a result of participation in such hazardous waste operations. Employees, contractors and subcontractors working outside of the operations part of a site are not covered by this standard.
Department of Transportation specified salvage drums or containers and suitable quantities of proper absorbent shall be kept available and used in areas where spills, leaks, or ruptures may occur.
The following procedures shall be followed in areas where drums or containers are being opened:
Material handiing equipment used to transfer drums and containers shall be selected, positioned and operated to minimize sources of ignition related to the equipment from igniting vapors released from ruptured drums or containers.
Drums and containers containing radioactive wastes shall not be handled until such time as their hazard to employees is properly assessed.
As a minimum, the following special precautions shall be taken when drums and containers containing or suspected of containing shock-sensitive wastes are handled:
Caution: Shipping of shock sensitive wastes may be prohibited under U.S. Department of Transportation regulations. Employers and their shippers should refer to 49 CFR 173.21 and 173.50.
In addition to the requirements of paragraph (j)(5) of this section, the following precautions shall be taken, as a minimum, in handling laboratory waste packs (lab packs):
Sampling of containers and drums shall be done in accordance with a sampling procedure which is part of the site safety and health plan developed for and available to employees and others at the specific worksite.
Procedures for all phases of decontamination shall be developed and implemented in accordance with this paragraph.
Decontamination shall be performed in geographical areas that will minimize the exposure of uncontaminated employees or equipment to contaminated employees or equipment.
All equipment and solvents used for decontamination shall be decontaminated or disposed of properly.
Unauthorized employees shall not remove protective clothing or equipment from change rooms.
Commercial laundries or cleaning establishments that decontaminate protective clothing or equipment shall be informed of the potentially harmful effects of exposures to hazardous substances.
Where the decontamination procedure indicates a need for regular showers and change rooms outside of a contaminated area, they shall be provided and meet the requirements of 29 CFR 1910.141. If temperature conditions prevent the effective use of water, then other effective means for cleansing shall be provided and used.
The employer shall develop an emergency response plan for emergencies which shall address, as a minimum, the following:
and emergency equipment.
Areas accessible to employees shall be lighted to not less than the minimum illumination intensities listed in the following Table H-120.1 while any work is in progress:
| Foot-candles | Area or operations |
|---|---|
| 5 | General site areas. |
| 3 | Excavation and waste areas, accessways, active storage areas, loading platforms, refueling, and field maintenance areas. |
| 5 | Indoors: Warehouses, corridors, hallways, and exitways. |
| 5 | Tunnels, shafts, and general underground work areas. (Exception: Minimum of 10 foot-candles is required at tunnel and shaft heading during drilling mucking, and scaling. Mine Safety and Health Administration approved cap lights shall be acceptable for use in the tunnel heading.) |
| 10 | General shops (e.g., mechanical and electrical equipment rooms, active storerooms, barracks or living quarters, locker or dressing rooms, dining areas, and indoor toilets and workrooms.) |
| 30 | First aid stations, infirmaries, and offices. |
| Number of employees | Minimum number of facilities |
|---|---|
| 20 or fewer | One. |
| More than 20, fewer than 200 | One toilet seat and one urinal per 40 employees. |
| More than 200 | One toilet seat and one urinal per 50 employees. |
All food service facilities and operations for employees shall meet the applicable laws, ordinances, and regulations of the jurisdictions in which they are located.
When temporary sleeping quarters are provided, they shall be heated, ventilated, and lighted.
The employer shall provide adequate washing facilities for employees engaged in operations where hazardous substances may be harmful to employees. Such facilities shall be in near proximity to the worksite; in areas where exposures are below permissible exposure limits and published exposure levels and which are under the controls of the employer; and shall be so equipped as to enable employees to remove hazardous substances from themselves.
When hazardous waste clean-up or removal operations commence on a site and the duration of the work will require six months or greater time to complete, the employer shall provide showers and change rooms for all employees exposed to hazardous substances and health hazards involved in hazardous waste clean-up or removal operations.
The employer shall develop and implement a written safety and health program for employees involved in hazardous waste operations that shall be available for inspection by employees, their representatives and OSHA personnel. The program shall be designed to identify, evaluate and control safety and health hazards in their facilities for the purpose of employee protection, to provide for emergency response meeting the requirements of paragraph (p)(8) of this section and to address as appropriate site analysis, engineering controls, maximum exposure limits, hazardous waste handling procedures and uses of new technologies.
The employer shall implement a hazard communication program meeting the requirements of 29 CFR 1910.1200 as part of the employer's safety and program.
The employer shall develop and implement a medical surveillance program meeting the requirements of paragraph (f) of this section.
The employer shall develop and implement a decontamination procedure meeting the requirements of paragraph (k) of this section.
The employer shall develop and implement procedures meeting the requirements of paragraph (o) of this section for introducing new and innovative equipment into the workplace.
Where employees will be handling drums or containers, the employer shall develop and implement procedures meeting the requirements of paragraphs (j)(1) (ii) through (viii) and (xi) of this section, as well as (j)(3) and (j)(8) of this section prior to starting such work.
The employer shall develop and implement a training program, which is part of the employer's safety and health program, for employees exposed to health hazards or hazardous substances at TSD operations to enable the employees to perform their assigned duties and functions in a safe and healthful manner so as not endanger themselves or other employees. The initial training shall be for 24 hours and refresher training shall be for eight hours annually. Employees who have received the initial training required by this paragraph shall be given a written certificate attesting that they have successfully completed the necessary training.
Employers who can show by an employee's previous work experience and/or training that the employee has had training equivalent to the initial training required by this paragraph, shall be considered as meeting the initial training requirements of this paragraph as to that employee. Equivalent training includes the training that existing employees might have already received from actual site work experience. Current employees shall receive eight hours of refresher training annually.
Trainers who teach initial training shall have satisfactorily completed a training course for teaching the subjects they are expected to teach or they shall have the academic credentials and instruction experience necessary to demonstrate a good command of the subject matter of the courses and competent instructional skills.
An emergency response plan shall be developed and implemented by all employers. Such plans need not duplicate any of the subjects fully addressed in the employer's contingency planning required by permits, such as those issued by the U.S. Environmental Protection Agency, provided that the contingency plan is made part of the emergency response plan. The emergency response plan shall be a written portion of the employer's safety and health program required in paragraph (p)(1) of this section. Employers who will evacuate their employees from the worksite location when an emergency occurs and who do not permit any of their employees to assist in handling the emergency are exempt from the requirements of paragraph (p)(8) if they provide an emergency action plan complying with 29 CFR 1910.38.
The employer shall develop an emergency response plan for emergencies which shall address, as a minimum, the following areas to the extent that they are not addressed in any specific program required in this paragraph:
and emergency equipment.
Exception #1: An employer need not train all employees to the degree specified if the employer divides the work force in a manner such that a sufficient number of employees who have responsibility to control emergencies have the training specified, and all other employees, who may first respond to an emergency incident, have sufficient awareness training to recognize that an emergency response situation exists and that they are instructed in that case to summon the fully trained employees and not attempt control activities for which they are not trained.
Exception #2: An employer need not train all employees to the degree specified if arrangements have been made in advance for an outside fully-trained emergency response team to respond in a reasonable period and all employees, who may come to the incident first, have sufficient awareness training to recognize that an emergency response situation exists and they have been instructed to call the designated outside fully-trained emergency response team for assistance.
This paragraph covers employers whose employees are engaged in emergency response no matter where it occurs except that it does not cover employees engaged in operations specified in paragraphs (a)(1)(i) through (a)(1)(iv) of this section. Those emergency response organizations who have developed and implemented programs equivalent to this paragraph for handling releases of hazardous substances pursuant to section 303 of the Superfund Amendments and Reauthorization Act of 1986 (Emergency Planning and Community Right-to-Know Act of 1986, 42 U.S.C. 11003) shall be deemed to have met the requirements of this paragraph.
An emergency response plan shall be developed and implemented to handle anticipated emergencies prior to the commencement of emergency response operations. The plan shall be in writing and available for inspection and copying by employees, their representatives and OSHA personnel. Employers who will evacuate their employees from the danger area when an emergency occurs, and who do not permit any of their employees to assist in handling the emergency, are exempt from the requirements of this paragraph if they provide an emergency action plan in accordance with 29 CFR 1910.38.
The employer shall develop an emergency response plan for emergencies which shall address, as a minimum, the following to the extent that they are not addressed elsewhere:
and emergency equipment.
Personnel, not necessarily an employer's own employees, who are skilled in the operation of certain equipment, such as mechanized earth moving or digging equipment or crane and hoisting equipment, and who are needed temporarily to perform immediate emergency support work that cannot reasonably be performed in a timely fashion by an employer's own employees, and who will be or may be exposed to the hazards at an emergency response scene, are not required to meet the training required in this paragraph for the employer's regular employees. However, these personnel shall be given an initial briefing at the site prior to their participation in any emergency response. The initial briefing shall include instruction in the wearing of appropriate personal protective equipment, what chemical hazards are involved, and what duties are to be performed. All other appropriate safety and health precautions provided to the employer's own employees shall be used to assure the safety and health of these personnel.
Employees who, in the course of their regular job duties, work with and are trained in the hazards of specific hazardous substances, and who will be called upon to provide technical advice or assistance at a hazardous substance release incident to the individual in charge, shall receive training or demonstrate competency in the area of their specialization annually.
Training shall be based on the duties and function to be performed by each responder of an emergency response organization. The skill and knowledge levels required for all new responders, those hired after the effective date of this standard, shall be conveyed to them through training before they are permitted to take part in actual emergency operations on an incident. Employees who participate, or are expected to participate, in emergency response, shall be given training in accordance with the following paragraphs:
First responders at the awareness level are individuals who are likely to witness or discover a hazardous substance release and who have been trained to initiate an emergency response sequence by notifying the proper authorities of the release. They would take no further action beyond notifying the authorities of the release. First responders at the awareness level shall have sufficient training or have had sufficient experience to objectively demonstrate competency in the following areas:
First responders at the operations level are individuals who respond to releases or potential releases of hazardous substances as part of the initial response to the site for the purpose of protecting nearby persons, property, or the environment from the effects of the release. They are trained to respond in a defensive fashion without actually trying to stop the release. Their function is to contain the release from a safe distance, keep it from spreading, and prevent exposures. First responders at the operational level shall have received at least eight hours of training or have had sufficient experience to objectively demonstrate competency in the following areas in addition to those listed for the awareness level and the employer shall so certify:
Hazardous materials technicians are individuals who respond to releases or potential releases for the purpose of stopping the release. They assume a more aggressive role than a first responder at the operations level in that they will approach the point of release in order to plug, patch or otherwise stop the release of a hazardous substance. Hazardous materials technicians shall have received at least 24 hours of training equal to the first responder operations level and in addition have competency in the following areas and the employer shall so certify:
Hazardous materials specialists are individuals who respond with and provide support to hazardous materials technicians. Their duties parallel those of the hazardous materials technician, however, those duties require a more directed or specific knowledge of the various substances they may be called upon to contain. The hazardous materials specialist would also act as the site liaison with Federal, state, local and other government authorities in regards to site activities. Hazardous materials specialists shall have received at least 24 hours of training equal to the technician level and in addition have competency in the following areas and the employer shall so certify:
Incident commanders, who will assume control of the incident scene beyond the first responder awareness level, shall receive at least 24 hours of training equal to the first responder operations level and in addition have competency in the following areas and the employer shall so certify:
Trainers who teach any of the above training subjects shall have satisfactorily completed a training course for teaching the subjects they are expected to teach, such as the courses offered by the U.S. National Fire Academy, or they shall have the training and/or academic credentials and instructional experience necessary to demonstrate competent instructional skills and a good command of the subject matter of the courses they are to teach.
Chemical protective clothing and equipment to be used by organized and designated HAZMAT team members, or to be used by hazardous materials specialists, shall meet the requirements of paragraphs (g) (3) through (5) of this section.
Upon completion of the emergency response, if it is determined that it is necessary to remove hazardous substances, health hazards, and materials contaminated with them (such as contaminated soil or other elements of the natural environment) from the site of the incident, the employer conducting the clean-up shall comply with one of the following:
Appendix A to § 1910.120—Personal Protective Equipment Test Methods
This appendix sets forth the non-mandatory examples of tests which may be used to evaluate compliance with § 1910.120 (g)(4) (ii) and (iii). Other tests and other challenge agents may be used to evaluate compliance.
A. Totally-encapsulating chemical protective suit pressure test
1.0—Scope
1.1 This practice measures the ability of a gas tight totally-encapsulating chemical protective suit material, seams, and closures to maintain a fixed positive pressure. The results of this practice allow the gas tight integrity of a totally-encapsulating chemical protective suit to be evaluated.
1.2 Resistance of the suit materials to permeation, penetration, and degradation by specific hazardous substances is not determined by this test method.
2.0—Definition of terms
2.1 Totally-encapsulated chemical protective suit (TECP suit) means a full body garment which is constructed of protective clothing materials; covers the wearer's torso, head, arms, legs and respirator; may cover the wearer's hands and feet with tightly attached gloves and boots; completely encloses the wearer and respirator by itself or in combination with the wearer's gloves and boots.
2.2 Protective clothing material means any material or combination of materials used in an item of clothing for the purpose of isolating parts of the body from direct contact with a potentially hazardous liquid or gaseous chemicals.
2.3 Gas tight means, for the purpose of this test method, the limited flow of a gas under pressure from the inside of a TECP suit to atmosphere at a prescribed pressure and time interval.
3.0—Summary of test method
3.1 The TECP suit is visually inspected and modified for the test. The test apparatus is attached to the suit to permit inflation to the pre-test suit expansion pressure for removal of suit wrinkles and creases. The pressure is lowered to the test pressure and monitored for three minutes. If the pressure drop is excessive, the TECP suit fails the test and is removed from service. The test is repeated after leak location and repair.
4.0—Required Supplies
4.1 Source of compressed air.
4.2 Test apparatus for suit testing, including a pressure measurement device with a sensitivity of at least 1/4 inch water gauge.
4.3 Vent valve closure plugs or sealing tape.
4.4 Soapy water solution and soft brush.
4.5 Stop watch or appropriate timing device.
5.0—Safety Precautions
5.1 Care shall be taken to provide the correct pressure safety devices required for the source of compressed air used.
6.0—Test Procedure
6.1 Prior to each test, the tester shall perform a visual inspection of the suit. Check the suit for seam integrity by visually examining the seams and gently pulling on the seams. Ensure that all air supply lines, fittings, visor, zippers, and valves are secure and show no signs of deterioration.
6.1.1 Seal off the vent valves along with any other normal inlet or exhaust points (such as umbilical air line fittings or face piece opening) with tape or other appropriate means (caps, plugs, fixture, etc.). Care should be exercised in the sealing process not to damage any of the suit components.
6.1.2 Close all closure assemblies.
6.1.3 Prepare the suit for inflation by providing an improvised connection point on the suit for connecting an airline. Attach the pressure test apparatus to the suit to permit suit inflation from a compressed air source equipped with a pressure indicating regulator. The leak tightness of the pressure test apparatus should be tested before and after each test by closing off the end of the tubing attached to the suit and assuring a pressure of three inches water gauge for three minutes can be maintained. If a component is removed for the test, that component shall be replaced and a second test conducted with another component removed to permit a complete test of the ensemble.
6.1.4 The pre-test expansion pressure (A) and the suit test pressure (B) shall be supplied by the suit manufacturer, but in no case shall they be less than: (A) = three inches water gauge; and (B) = two inches water gauge. The ending suit pressure (C) shall be no less than 80 percent of the test pressure (B); i.e., the pressure drop shall not exceed 20 percent of the test pressure (B).
6.1.5 Inflate the suit until the pressure inside is equal to pressure (A), the pre-test expansion suit pressure. Allow at least one minute to fill out the wrinkles in the suit. Release sufficient air to reduce the suit pressure to pressure (B), the suit test pressure. Begin timing. At the end of three minutes, record the suit pressure as pressure (C), the ending suit pressure. The difference between the suit test pressure and the ending suit test pressure (B − C) shall be defined as the suit pressure drop.
6.1.6 If the suit pressure drop is more than 20 percent of the suit test pressure (B) during the three-minute test period, the suit fails the test and shall be removed from service.
7.0—Retest Procedure
7.1 If the suit fails the test check for leaks by inflating the suit to pressure (A) and brushing or wiping the entire suit (including seams, closures, lens gaskets, glove-to-sleeve joints, etc.) with a mild soap and water solution. Observe the suit for the formation of soap bubbles, which is an indication of a leak. Repair all identified leaks.
7.2 Retest the TECP suit as outlined in Test procedure 6.0.
8.0—Report
8.1 Each TECP suit tested by this practice shall have the following information recorded:
8.1.1 Unique identification number, identifying brand name, date of purchase, material of construction, and unique fit features, e.g., special breathing apparatus.
8.1.2 The actual values for test pressures (A), (B), and (C) shall be recorded along with the specific observation times. If the ending pressure (C) is less than 80 percent of the test pressure (B), the suit shall be identified as failing the test. When possible, the specific leak location shall be identified in the test records. Retest pressure data shall be recorded as an additional test.
8.1.3 The source of the test apparatus used shall be identified and the sensitivity of the pressure gauge shall be recorded.
8.1.4 Records shall be kept for each pressure test even if repairs are being made at the test location.
Caution
Visually inspect all parts of the suit to be sure they are positioned correctly and secured tightly before putting the suit back into service. Special care should be taken to examine each exhaust valve to make sure it is not blocked.
Care should also be exercised to assure that the inside and outside of the suit is completely dry before it is put into storage.
B. Totally-encapsulating chemical protective suit qualitative leak test
1.0—Scope
1.1 This practice semi-qualitatively tests gas tight totally-encapsulating chemical protective suit integrity by detecting inward leakage of ammonia vapor. Since no modifications are made to the suit to carry out this test, the results from this practice provide a realistic test for the integrity of the entire suit.
1.2 Resistance of the suit materials to permeation, penetration, and degradation is not determined by this test method. ASTM test methods are available to test suit materials for these characteristics and the tests are usually conducted by the manufacturers of the suits.
2.0—Definition of terms
2.1 Totally-encapsulated chemical protective suit (TECP suit) means a full body garment which is constructed of protective clothing materials; covers the wearer's torso, head, arms, legs and respirator; may cover the wearer's hands and feet with tightly attached gloves and boots; completely encloses the wearer and respirator by itself or in combination with the wearer's gloves, and boots.
2.2 Protective clothing material means any material or combination of materials used in an item of clothing for the purpose of isolating parts of the body from direct contact with a potentially hazardous liquid or gaseous chemicals.
2.3 Gas tight means, for the purpose of this test method, the limited flow of a gas under pressure from the inside of a TECP suit to atmosphere at a prescribed pressure and time interval.
2.4 Intrusion Coefficient means a number expressing the level of protection provided by a gas tight totally-encapsulating chemical protective suit. The intrusion coefficient is calculated by dividing the test room challenge agent concentration by the concentration of challenge agent found inside the suit. The accuracy of the intrusion coefficient is dependent on the challenge agent monitoring methods. The larger the intrusion coefficient the greater the protection provided by the TECP suit.
3.0—Summary of recommended practice
3.1 The volume of concentrated aqueous ammonia solution (ammonia hydroxide NH 4 OH) required to generate the test atmosphere is determined using the directions outlined in 6.1. The suit is donned by a person wearing the appropriate respiratory equipment (either a positive pressure self-contained breathing apparatus or a positive pressure supplied air respirator) and worn inside the enclosed test room. The concentrated aqueous ammonia solution is taken by the suited individual into the test room and poured into an open plastic pan. A two-minute evaporation period is observed before the test room concentration is measured, using a high range ammonia length of stain detector tube. When the ammonia vapor reaches a concentration of between 1000 and 1200 ppm, the suited individual starts a standardized exercise protocol to stress and flex the suit. After this protocol is completed, the test room concentration is measured again. The suited individual exits the test room and his stand-by person measures the ammonia concentration inside the suit using a low range ammonia length of stain detector tube or other more sensitive ammonia detector. A stand-by person is required to observe the test individual during the test procedure; aid the person in donning and doffing the TECP suit; and monitor the suit interior. The intrusion coefficient of the suit can be calculated by dividing the average test area concentration by the interior suit concentration. A colorimetric ammonia indicator strip of bromophenol blue or equivalent is placed on the inside of the suit face piece lens so that the suited individual is able to detect a color change and know if the suit has a significant leak. If a color change is observed the individual shall leave the test room immediately.
4.0—Required supplies
4.1 A supply of concentrated aqueous ammonium hydroxide (58% by weight).
4.2 A supply of bromophenol/blue indicating paper or equivalent, sensitive to 5-10 ppm ammonia or greater over a two-minute period of exposure. [pH 3.0 (yellow) to pH 4.6 (blue)]
4.3 A supply of high range (0.5-10 volume percent) and low range (5-700 ppm) detector tubes for ammonia and the corresponding sampling pump. More sensitive ammonia detectors can be substituted for the low range detector tubes to improve the sensitivity of this practice.
4.4 A shallow plastic pan (PVC) at least 12″:14″:1″ and a half pint plastic container (PVC) with tightly closing lid.
4.5 A graduated cylinder or other volumetric measuring device of at least 50 milliliters in volume with an accuracy of at least ±1 milliliters.
5.0—Safety precautions
5.1 Concentrated aqueous ammonium hydroxide, NH 4 OH, is a corrosive volatile liquid requiring eye, skin, and respiratory protection. The person conducting the test shall review the SDS for aqueous ammonia.
5.2 Since the established permissible exposure limit for ammonia is 35 ppm as a 15 minute STEL, only persons wearing a positive pressure self-contained breathing apparatus or a positive pressure supplied air respirator shall be in the chamber. Normally only the person wearing the totally-encapsulating suit will be inside the chamber. A stand-by person shall have a positive pressure self-contained breathing apparatus, or a positive pressure supplied air respirator available to enter the test area should the suited individual need assistance.
5.3 A method to monitor the suited individual must be used during this test. Visual contact is the simplest but other methods using communication devices are acceptable.
5.4 The test room shall be large enough to allow the exercise protocol to be carried out and then to be ventilated to allow for easy exhaust of the ammonia test atmosphere after the test(s) are completed.
5.5 Individuals shall be medically screened for the use of respiratory protection and checked for allergies to ammonia before participating in this test procedure.
6.0—Test procedure
6.1.1 Measure the test area to the nearest foot and calculate its volume in cubic feet. Multiply the test area volume by 0.2 milliliters of concentrated aqueous ammonia solution per cubic foot of test area volume to determine the approximate volume of concentrated aqueous ammonia required to generate 1000 ppm in the test area.
6.1.2 Measure this volume from the supply of concentrated aqueous ammonia and place it into a closed plastic container.
6.1.3 Place the container, several high range ammonia detector tubes, and the pump in the clean test pan and locate it near the test area entry door so that the suited individual has easy access to these supplies.
6.2.1 In a non-contaminated atmosphere, open a pre-sealed ammonia indicator strip and fasten one end of the strip to the inside of the suit face shield lens where it can be seen by the wearer. Moisten the indicator strip with distilled water. Care shall be taken not to contaminate the detector part of the indicator paper by touching it. A small piece of masking tape or equivalent should be used to attach the indicator strip to the interior of the suit face shield.
6.2.2 If problems are encountered with this method of attachment, the indicator strip can be attached to the outside of the respirator face piece lens being used during the test.
6.3 Don the respiratory protective device normally used with the suit, and then don the TECP suit to be tested. Check to be sure all openings which are intended to be sealed (zippers, gloves, etc.) are completely sealed. DO NOT, however, plug off any venting valves.
6.4 Step into the enclosed test room such as a closet, bathroom, or test booth, equipped with an exhaust fan. No air should be exhausted from the chamber during the test because this will dilute the ammonia challenge concentrations.
6.5 Open the container with the pre-measured volume of concentrated aqueous ammonia within the enclosed test room, and pour the liquid into the empty plastic test pan. Wait two minutes to allow for adequate volatilization of the concentrated aqueous ammonia. A small mixing fan can be used near the evaporation pan to increase the evaporation rate of the ammonia solution.
6.6 After two minutes a determination of the ammonia concentration within the chamber should be made using the high range colorimetric detector tube. A concentration of 1000 ppm ammonia or greater shall be generated before the exercises are started.
6.7 To test the integrity of the suit the following four minute exercise protocol should be followed:
6.7.1 Raising the arms above the head with at least 15 raising motions completed in one minute.
6.7.2 Walking in place for one minute with at least 15 raising motions of each leg in a one-minute period.
6.7.3 Touching the toes with a least 10 complete motions of the arms from above the head to touching of the toes in a one-minute period.
6.7.4 Knee bends with at least 10 complete standing and squatting motions in a one-minute period.
6.8 If at any time during the test the colorimetric indicating paper should change colors, the test should be stopped and section 6.10 and 6.12 initiated (See ¶ 4.2).
6.9 After completion of the test exercise, the test area concentration should be measured again using the high range colorimetric detector tube.
6.10 Exit the test area.
6.11 The opening created by the suit zipper or other appropriate suit penetration should be used to determine the ammonia concentration in the suit with the low range length of stain detector tube or other ammonia monitor. The internal TECP suit air should be sampled far enough from the enclosed test area to prevent a false ammonia reading.
6.12 After completion of the measurement of the suit interior ammonia concentration the test is concluded and the suit is doffed and the respirator removed.
6.13 The ventilating fan for the test room should be turned on and allowed to run for enough time to remove the ammonia gas. The fan shall be vented to the outside of the building.
6.14 Any detectable ammonia in the suit interior (five ppm ammonia (NH 3 ) or more for the length of stain detector tube) indicates that the suit has failed the test. When other ammonia detectors are used a lower level of detection is possible, and it should be specified as the pass/fail criteria.
6.15 By following this test method, an intrusion coefficient of approximately 200 or more can be measured with the suit in a completely operational condition. If the intrusion coefficient is 200 or more, then the suit is suitable for emergency response and field use.
7.0—Retest procedures
7.1 If the suit fails this test, check for leaks by following the pressure test in test A above.
7.2 Retest the TECP suit as outlined in the test procedure 6.0.
8.0—Report
8.1 Each gas tight totally-encapsulating chemical protective suit tested by this practice shall have the following information recorded.
8.1.1 Unique identification number, identifying brand name, date of purchase, material of construction, and unique suit features; e.g., special breathing apparatus.
8.1.2 General description of test room used for test.
8.1.3 Brand name and purchase date of ammonia detector strips and color change data.
8.1.4 Brand name, sampling range, and expiration date of the length of stain ammonia detector tubes. The brand name and model of the sampling pump should also be recorded. If another type of ammonia detector is used, it should be identified along with its minimum detection limit for ammonia.
8.1.5 Actual test results shall list the two test area concentrations, their average, the interior suit concentration, and the calculated intrusion coefficient. Retest data shall be recorded as an additional test.
8.2 The evaluation of the data shall be specified as “suit passed” or “suit failed,” and the date of the test. Any detectable ammonia (five ppm or greater for the length of stain detector tube) in the suit interior indicates the suit has failed this test. When other ammonia detectors are used, a lower level of detection is possible and it should be specified as the pass fail criteria.
Caution
Visually inspect all parts of the suit to be sure they are positioned correctly and secured tightly before putting the suit back into service. Special care should be taken to examine each exhaust valve to make sure it is not blocked.
Care should also be exercised to assure that the inside and outside of the suit is completely dry before it is put into storage.
Appendix B to § 1910.120—General Description and Discussion of the Levels of Protection and Protective Gear
This appendix sets forth information about personal protective equipment (PPE) protection levels which may be used to assist employers in complying with the PPE requirements of this section.
As required by the standard, PPE must be selected which will protect employees from the specific hazards which they are likely to encounter during their work on-site.
Selection of the appropriate PPE is a complex process which should take into consideration a variety of factors. Key factors involved in this process are identification of the hazards, or suspected hazards; their routes of potential hazard to employees (inhalation, skin absorption, ingestion, and eye or skin contact); and the performance of the PPE materials (and seams) in providing a barrier to these hazards. The amount of protection provided by PPE is material-hazard specific. That is, protective equipment materials will protect well against some hazardous substances and poorly, or not at all, against others. In many instances, protective equipment materials cannot be found which will provide continuous protection from the particular hazardous substance. In these cases the breakthrough time of the protective material should exceed the work durations.
Other factors in this selection process to be considered are matching the PPE to the employee's work requirements and task-specific conditions. The durability of PPE materials, such as tear strength and seam strength, should be considered in relation to the employee's tasks. The effects of PPE in relation to heat stress and task duration are a factor in selecting and using PPE. In some cases layers of PPE may be necessary to provide sufficient protection, or to protect expensive PPE inner garments, suits or equipment.
The more that is known about the hazards at the site, the easier the job of PPE selection becomes. As more information about the hazards and conditions at the site becomes available, the site supervisor can make decisions to up-grade or down-grade the level of PPE protection to match the tasks at hand.
The following are guidelines which an employer can use to begin the selection of the appropriate PPE. As noted above, the site information may suggest the use of combinations of PPE selected from the different protection levels (i.e., A, B, C, or D) as being more suitable to the hazards of the work. It should be cautioned that the listing below does not fully address the performance of the specific PPE material in relation to the specific hazards at the job site, and that PPE selection, evaluation and re-selection is an ongoing process until sufficient information about the hazards and PPE performance is obtained.
Part A. Personal protective equipment is divided into four categories based on the degree of protection afforded. (See part B of this appendix for further explanation of Levels A, B, C, and D hazards.)
I. Level A —To be selected when the greatest level of skin, respiratory, and eye protection is required.
The following constitute Level A equipment; it may be used as appropriate;
1. Positive pressure, full face-piece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA, approved by the National Institute for Occupational Safety and Health (NIOSH).
2. Totally-encapsulating chemical-protective suit.
3. Coveralls. 1
4. Long underwear. 1
5. Gloves, outer, chemical-resistant.
6. Gloves, inner, chemical-resistant.
7. Boots, chemical-resistant, steel toe and shank.
8. Hard hat (under suit). 1
9. Disposable protective suit, gloves and boots (depending on suit construction, may be worn over totally-encapsulating suit).
II. Level B —The highest level of respiratory protection is necessary but a lesser level of skin protection is needed.
The following constitute Level B equipment; it may be used as appropriate.
1. Positive pressure, full-facepiece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA (NIOSH approved).
2. Hooded chemical-resistant clothing (overalls and long-sleeved jacket; coveralls; one or two-piece chemical-splash suit; disposable chemical-resistant overalls).
3. Coveralls. 1
4. Gloves, outer, chemical-resistant.
5. Gloves, inner, chemical-resistant.
6. Boots, outer, chemical-resistant steel toe and shank.
7. Boot-covers, outer, chemical-resistant (disposable). 1
8. Hard hat. 1
9. [Reserved]
10. Face shield. 1
III. Level C —The concentration(s) and type(s) of airborne substance(s) is known and the criteria for using air purifying respirators are met.
The following constitute Level C equipment; it may be used as appropriate.
1. Full-face or half-mask, air purifying respirators (NIOSH approved).
2. Hooded chemical-resistant clothing (overalls; two-piece chemical-splash suit; disposable chemical-resistant overalls).
3. Coveralls. 1
1 Optional, as applicable.
4. Gloves, outer, chemical-resistant.
5. Gloves, inner, chemical-resistant.
6. Boots (outer), chemical-resistant steel toe and shank. 1
7. Boot-covers, outer, chemical-resistant (disposable) 1.
8. Hard hat. 1
9. Escape mask. 1
10. Face shield. 1
IV. Level D —A work uniform affording minimal protection, used for nuisance contamination only.
The following constitute Level D equipment; it may be used as appropriate:
1. Coveralls.
2. Gloves. 1
3. Boots/shoes, chemical-resistant steel toe and shank.
4. Boots, outer, chemical-resistant (disposable). 1
5. Safety glasses or chemical splash goggles*.
6. Hard hat. 1
7. Escape mask. 1
8. Face shield. 1
Part B. The types of hazards for which levels A, B, C, and D protection are appropriate are described below:
I. Level A —Level A protection should be used when:
1. The hazardous substance has been identified and requires the highest level of protection for skin, eyes, and the respiratory system based on either the measured (or potential for) high concentration of atmospheric vapors, gases, or particulates; or the site operations and work functions involve a high potential for splash, immersion, or exposure to unexpected vapors, gases, or particulates of materials that are harmful to skin or capable of being absorbed through the skin;
2. Substances with a high degree of hazard to the skin are known or suspected to be present, and skin contact is possible; or
3. Operations are being conducted in confined, poorly ventilated areas, and the absence of conditions requiring Level A have not yet been determined.
II. Level B —Level B protection should be used when:
1. The type and atmospheric concentration of substances have been identified and require a high level of respiratory protection, but less skin protection;
2. The atmosphere contains less than 19.5 percent oxygen; or
3. The presence of incompletely identified vapors or gases is indicated by a direct-reading organic vapor detection instrument, but vapors and gases are not suspected of containing high levels of chemicals harmful to skin or capable of being absorbed through the skin.
III. Level C —Level C protection should be used when:
1. The atmospheric contaminants, liquid splashes, or other direct contact will not adversely affect or be absorbed through any exposed skin;
2. The types of air contaminants have been identified, concentrations measured, and an air-purifying respirator is available that can remove the contaminants; and
3. All criteria for the use of air-purifying respirators are met.
IV. Level D —Level D protection should be used when:
1. The atmosphere contains no known hazard; and
2. Work functions preclude splashes, immersion, or the potential for unexpected inhalation of or contact with hazardous levels of any chemicals.
As an aid in selecting suitable chemical protective clothing, it should be noted that the National Fire Protection Association (NFPA) has developed standards on chemical protective clothing. The standards that have been adopted by include:
NFPA 1991—Standard on Vapor-Protective Suits for Hazardous Chemical Emergencies (EPA Level A Protective Clothing).
NFPA 1992—Standard on Liquid Splash-Protective Suits for Hazardous Chemical Emergencies (EPA Level B Protective Clothing).
NFPA 1993—Standard on Liquid Splash-Protective Suits for Non-emergency, Non-flammable Hazardous Chemical Situations (EPA Level B Protective Clothing).
These standards apply documentation and performance requirements to the manufacture of chemical protective suits. Chemical protective suits meeting these requirements are labelled as compliant with the appropriate standard. It is recommended that chemical protective suits that meet these standards be used.
Appendix C to § 1910.120—Compliance Guidelines
1. Occupational Safety and Health Program. Each hazardous waste site clean-up effort will require an occupational safety and health program headed by the site coordinator or the employer's representative. The purpose of the program will be the protection of employees at the site and will be an extension of the employer's overall safety and health program. The program will need to be developed before work begins on the site and implemented as work proceeds as stated in paragraph (b). The program is to facilitate coordination and communication of safety and health issues among personnel responsible for the various activities which will take place at the site. It will provide the overall means for planning and implementing the needed safety and health training and job orientation of employees who will be working at the site. The program will provide the means for identifying and controlling worksite hazards and the means for monitoring program effectiveness. The program will need to cover the responsibilities and authority of the site coordinator or the employer's manager on the site for the safety and health of employees at the site, and the relationships with contractors or support services as to what each employer's safety and health responsibilities are for their employees on the site. Each contractor on the site needs to have its own safety and health program so structured that it will smoothly interface with the program of the site coordinator or principal contractor.
Also those employers involved with treating, storing or disposal of hazardous waste as covered in paragraph (p) must have implemented a safety and health program for their employees. This program is to include the hazard communication program required in paragraph (p)(1) and the training required in paragraphs (p)(7) and (p)(8) as parts of the employers comprehensive overall safety and health program. This program is to be in writing.
Each site or workplace safety and health program will need to include the following: (1) Policy statements of the line of authority and accountability for implementing the program, the objectives of the program and the role of the site safety and health supervisor or manager and staff; (2) means or methods for the development of procedures for identifying and controlling workplace hazards at the site; (3) means or methods for the development and communication to employees of the various plans, work rules, standard operating procedures and practices that pertain to individual employees and supervisors; (4) means for the training of supervisors and employees to develop the needed skills and knowledge to perform their work in a safe and healthful manner; (5) means to anticipate and prepare for emergency situations; and (6) means for obtaining information feedback to aid in evaluating the program and for improving the effectiveness of the program. The management and employees should be trying continually to improve the effectiveness of the program thereby enhancing the protection being afforded those working on the site.
Accidents on the site or workplace should be investigated to provide information on how such occurrences can be avoided in the future. When injuries or illnesses occur on the site or workplace, they will need to be investigated to determine what needs to be done to prevent this incident from occurring again. Such information will need to be used as feedback on the effectiveness of the program and the information turned into positive steps to prevent any reoccurrence. Receipt of employee suggestions or complaints relating to safety and health issues involved with site or workplace activities is also a feedback mechanism that can be used effectively to improve the program and may serve in part as an evaluative tool(s).
For the development and implementation of the program to be the most effective, professional safety and health personnel should be used. Certified Safety Professionals, Board Certified Industrial Hygienists or Registered Professional Safety Engineers are good examples of professional stature for safety and health managers who will administer the employer's program.
2. Training. The training programs for employees subject to the requirements of paragraph (e) of this standard should address: the safety and health hazards employees should expect to find on hazardous waste clean-up sites; what control measures or techniques are effective for those hazards; what monitoring procedures are effective in characterizing exposure levels; what makes an effective employer's safety and health program; what a site safety and health plan should include; hands on training with personal protective equipment and clothing they may be expected to use; the contents of the OSHA standard relevant to the employee's duties and function; and, employee's responsibilities under OSHA and other regulations. Supervisors will need training in their responsibilities under the safety and health program and its subject areas such as the spill containment program, the personal protective equipment program, the medical surveillance program, the emergency response plan and other areas.
The training programs for employees subject to the requirements of paragraph (p) of this standard should address: the employers safety and health program elements impacting employees; the hazard communication program; the medical surveillance program; the hazards and the controls for such hazards that employees need to know for their job duties and functions. All require annual refresher training.
The training programs for employees covered by the requirements of paragraph (q) of this standard should address those competencies required for the various levels of response such as: the hazards associated with hazardous substances; hazard identification and awareness; notification of appropriate persons; the need for and use of personal protective equipment including respirators; the decontamination procedures to be used; preplanning activities for hazardous substance incidents including the emergency reponse plan; company standard operating procedures for hazardous substance emergency responses; the use of the incident command system and other subjects. Hands-on training should be stressed whenever possible. Critiques done after an incident which include an evaluation of what worked and what did not and how could the incident be better handled the next time may be counted as training time.
For hazardous materials specialists (usually members of hazardous materials teams), the training should address the care, use and/or testing of chemical protective clothing including totally encapsulating suits, the medical surveillance program, the standard operating procedures for the hazardous materials team including the use of plugging and patching equipment and other subject areas.
Officers and leaders who may be expected to be in charge at an incident should be fully knowledgeable of their company's incident command system. They should know where and how to obtain additional assistance and be familiar with the local district's emergency response plan and the state emergency response plan.
Specialist employees such as technical experts, medical experts or environmental experts that work with hazardous materials in their regular jobs, who may be sent to the incident scene by the shipper, manufacturer or governmental agency to advise and assist the person in charge of the incident should have training on an annual basis. Their training should include the care and use of personal protective equipment including respirators; knowledge of the incident command system and how they are to relate to it; and those areas needed to keep them current in their respective field as it relates to safety and health involving specific hazardous substances.
Those skilled support personnel, such as employees who work for public works departments or equipment operators who operate bulldozers, sand trucks, backhoes, etc., who may be called to the incident scene to provide emergency support assistance, should have at least a safety and health briefing before entering the area of potential or actual exposure. These skilled support personnel, who have not been a part of the emergency response plan and do not meet the training requirements, should be made aware of the hazards they face and should be provided all necessary protective clothing and equipment required for their tasks.
There are two National Fire Protection Association standards, NFPA 472—“Standard for Professional Competence of Responders to Hazardous Material Incidents” and NFPA 471—“Recommended Practice for Responding to Hazardous Material Incidents”, which are excellent resource documents to aid fire departments and other emergency response organizations in developing their training program materials. NFPA 472 provides guidance on the skills and knowledge needed for first responder awareness level, first responder operations level, hazmat technicians, and hazmat specialist. It also offers guidance for the officer corp who will be in charge of hazardous substance incidents.
3. Decontamination. Decontamination procedures should be tailored to the specific hazards of the site, and may vary in complexity and number of steps, depending on the level of hazard and the employee's exposure to the hazard. Decontamination procedures and PPE decontamination methods will vary depending upon the specific substance, since one procedure or method may not work for all substances. Evaluation of decontamination methods and procedures should be performed, as necessary, to assure that employees are not exposed to hazards by re-using PPE. References in appendix D may be used for guidance in establishing an effective decontamination program. In addition, the U.S. Coast Guard's Manual, “Policy Guidance for Response to Hazardous Chemical Releases,” U.S. Department of Transportation, Washington, DC (COMDTINST M16465.30) is a good reference for establishing an effective decontamination program.
4. Emergency response plans. States, along with designated districts within the states, will be developing or have developed local emergency response plans. These state and district plans should be utilized in the emergency response plans called for in the standard. Each employer should assure that its emergency response plan is compatible with the local plan. The major reference being used to aid in developing the state and local district plans is the Hazardous Materials Emergency Planning Guide, NRT-1. The current Emergency Response Guidebook from the U.S. Department of Transportation, CMA's CHEMTREC and the Fire Service Emergency Management Handbook may also be used as resources.
Employers involved with treatment, storage, and disposal facilities for hazardous waste, which have the required contingency plan called for by their permit, would not need to duplicate the same planning elements. Those items of the emergency response plan that are properly addressed in the contingency plan may be substituted into the emergency response plan required in 1910.120 or otherwise kept together for employer and employee use.
5. Personal protective equipment programs. The purpose of personal protective clothing and equipment (PPE) is to shield or isolate individuals from the chemical, physical, and biologic hazards that may be encountered at a hazardous substance site.
As discussed in appendix B, no single combination of protective equipment and clothing is capable of protecting against all hazards. Thus PPE should be used in conjunction with other protective methods and its effectiveness evaluated periodically.
The use of PPE can itself create significant worker hazards, such as heat stress, physical and psychological stress, and impaired vision, mobility, and communication. For any given situation, equipment and clothing should be selected that provide an adequate level of protection. However, over-protection, as well as under-protection, can be hazardous and should be avoided where possible.
Two basic objectives of any PPE program should be to protect the wearer from safety and health hazards, and to prevent injury to the wearer from incorrect use and/or malfunction of the PPE. To accomplish these goals, a comprehensive PPE program should include hazard identification, medical monitoring, environmental surveillance, selection, use, maintenance, and decontamination of PPE and its associated training.
The written PPE program should include policy statements, procedures, and guidelines. Copies should be made available to all employees, and a reference copy should be made available at the worksite. Technical data on equipment, maintenance manuals, relevant regulations, and other essential information should also be collected and maintained.
6. Incident command system (ICS). Paragraph 1910.120(q)(3)(ii) requires the implementation of an ICS. The ICS is an organized approach to effectively control and manage operations at an emergency incident. The individual in charge of the ICS is the senior official responding to the incident. The ICS is not much different than the “command post” approach used for many years by the fire service. During large complex fires involving several companies and many pieces of apparatus, a command post would be established. This enabled one individual to be in charge of managing the incident, rather than having several officers from different companies making separate, and sometimes conflicting, decisions. The individual in charge of the command post would delegate responsibility for performing various tasks to subordinate officers. Additionally, all communications were routed through the command post to reduce the number of radio transmissions and eliminate confusion. However, strategy, tactics, and all decisions were made by one individual.
The ICS is a very similar system, except it is implemented for emergency response to all incidents, both large and small, that involve hazardous substances.
For a small incident, the individual in charge of the ICS may perform many tasks of the ICS. There may not be any, or little, delegation of tasks to subordinates. For example, in response to a small incident, the individual in charge of the ICS, in addition to normal command activities, may become the safety officer and may designate only one employee (with proper equipment) as a back-up to provide assistance if needed. OSHA does recommend, however, that at least two employees be designated as back-up personnel since the assistance needed may include rescue.
To illustrate the operation of the ICS, the following scenario might develop during a small incident, such as an overturned tank truck with a small leak of flammable liquid.
The first responding senior officer would implement and take command of the ICS. That person would size-up the incident and determine if additional personnel and apparatus were necessary; would determine what actions to take to control the leak; and, determine the proper level of personal protective equipment. If additional assistance is not needed, the individual in charge of the ICS would implement actions to stop and control the leak using the fewest number of personnel that can effectively accomplish the tasks. The individual in charge of the ICS then would designate himself as the safety officer and two other employees as a back-up in case rescue may become necessary. In this scenario, decontamination procedures would not be necessary.
A large complex incident may require many employees and difficult, time-consuming efforts to control. In these situations, the individual in charge of the ICS will want to delegate different tasks to subordinates in order to maintain a span of control that will keep the number of subordinates, that are reporting, to a manageable level.
Delegation of task at large incidents may be by location, where the incident scene is divided into sectors, and subordinate officers coordinate activities within the sector that they have been assigned.
Delegation of tasks can also be by function. Some of the functions that the individual in charge of the ICS may want to delegate at a large incident are: medical services; evacuation; water supply; resources (equipment, apparatus); media relations; safety; and, site control (integrate activities with police for crowd and traffic control). Also for a large incident, the individual in charge of the ICS will designate several employees as back-up personnel; and a number of safety officers to monitor conditions and recommend safety precautions.
Therefore, no matter what size or complexity an incident may be, by implementing an ICS there will be one individual in charge who makes the decisions and gives directions; and, all actions, and communications are coordinated through one central point of command. Such a system should reduce confusion, improve safety, organize and coordinate actions, and should facilitate effective management of the incident.
7. Site Safety and Control Plans. The safety and security of response personnel and others in the area of an emergeny response incident site should be of primary concern to the incident commander. The use of a site safety and control plan could greatly assist those in charge of assuring the safety and health of employees on the site.
A comprehensive site safety and control plan should include the following: summary analysis of hazards on the site and a risk analysis of those hazards; site map or sketch; site work zones (clean zone, transition or decontamination zone, work or hot zone); use of the buddy system; site communications; command post or command center; standard operating procedures and safe work practices; medical assistance and triage area; hazard monitoring plan (air contaminate monitoring, etc.); decontamination procedures and area; and other relevant areas. This plan should be a part of the employer's emergency response plan or an extension of it to the specific site.
8. Medical surveillance programs. Workers handling hazardous substances may be exposed to toxic chemicals, safety hazards, biologic hazards, and radiation. Therefore, a medical surveillance program is essential to assess and monitor workers' health and fitness for employment in hazardous waste operations and during the course of work; to provide emergency and other treatment as needed; and to keep accurate records for future reference.
The Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities developed by the National Institute for Occupational Safety and Health (NIOSH), the Occupational Safety and Health Administration (OSHA), the U.S. Coast Guard (USCG), and the Environmental Protection Agency (EPA); October 1985 provides an excellent example of the types of medical testing that should be done as part of a medical surveillance program.
9. New Technology and Spill Containment Programs. Where hazardous substances may be released by spilling from a container that will expose employees to the hazards of the materials, the employer will need to implement a program to contain and control the spilled material. Diking and ditching, as well as use of absorbents like diatomaceous earth, are traditional techniques which have proven to be effective over the years. However, in recent years new products have come into the marketplace, the use of which complement and increase the effectiveness of these traditional methods. These new products also provide emergency responders and others with additional tools or agents to use to reduce the hazards of spilled materials.
These agents can be rapidly applied over a large area and can be uniformly applied or otherwise can be used to build a small dam, thus improving the workers' ability to control spilled material. These application techniques enhance the intimate contact between the agent and the spilled material allowing for the quickest effect by the agent or quickest control of the spilled material. Agents are available to solidify liquid spilled materials, to suppress vapor generation from spilled materials, and to do both. Some special agents, which when applied as recommended by the manufacturer, will react in a controlled manner with the spilled material to neutralize acids or caustics, or greatly reduce the level of hazard of the spilled material.
There are several modern methods and devices for use by emergency response personnel or others involved with spill control efforts to safely apply spill control agents to control spilled material hazards. These include portable pressurized applicators similar to hand-held portable fire extinguishing devices, and nozzle and hose systems similar to portable fire fighting foam systems which allow the operator to apply the agent without having to come into contact with the spilled material. The operator is able to apply the agent to the spilled material from a remote position.
The solidification of liquids provides for rapid containment and isolation of hazardous substance spills. By directing the agent at run-off points or at the edges of the spill, the reactant solid will automatically create a barrier to slow or stop the spread of the material. Clean-up of hazardous substances is greatly improved when solidifying agents, acid or caustic neutralizers, or activated carbon adsorbents are used. Properly applied, these agents can totally solidify liquid hazardous substances or neutralize or absorb them, which results in materials which are less hazardous and easier to handle, transport, and dispose of. The concept of spill treatment, to create less hazardous substances, will improve the safety and level of protection of employees working at spill clean-up operations or emergency response operations to spills of hazardous substances.
The use of vapor suppression agents for volatile hazardous substances, such as flammable liquids and those substances which present an inhalation hazard, is important for protecting workers. The rapid and uniform distribution of the agent over the surface of the spilled material can provide quick vapor knockdown. There are temporary and long-term foam-type agents which are effective on vapors and dusts, and activated carbon adsorption agents which are effective for vapor control and soaking-up of the liquid. The proper use of hose lines or hand-held portable pressurized applicators provides good mobility and permits the worker to deliver the agent from a safe distance without having to step into the untreated spilled material. Some of these systems can be recharged in the field to provide coverage of larger spill areas than the design limits of a single charged applicator unit. Some of the more effective agents can solidify the liquid flammable hazardous substances and at the same time elevate the flashpoint above 140 °F so the resulting substance may be handled as a nonhazardous waste material if it meets the U.S. Environmental Protection Agency's 40 CFR part 261 requirements (See particularly § 261.21).
All workers performing hazardous substance spill control work are expected to wear the proper protective clothing and equipment for the materials present and to follow the employer's established standard operating procedures for spill control. All involved workers need to be trained in the established operating procedures; in the use and care of spill control equipment; and in the associated hazards and control of such hazards of spill containment work.
These new tools and agents are the things that employers will want to evaluate as part of their new technology program. The treatment of spills of hazardous substances or wastes at an emergency incident as part of the immediate spill containment and control efforts is sometimes acceptable to EPA and a permit exception is described in 40 CFR 264.1(g)(8) and 265.1(c)(11).
Appendix D to § 1910.120—References
The following references may be consulted for further information on the subject of this standard:
1. OSHA Instruction DFO CPL 2.70—January 29, 1986, Special Emphasis Program: Hazardous Waste Sites.
2. OSHA Instruction DFO CPL 2-2.37A—January 29, 1986, Technical Assistance and Guidelines for Superfund and Other Hazardous Waste Site Activities.
3. OSHA Instruction DTS CPL 2.74—January 29, 1986, Hazardous Waste Activity Form, OSHA 175.
4. Hazardous Waste Inspections Reference Manual, U.S. Department of Labor, Occupational Safety and Health Administration, 1986.
5. Memorandum of Understanding Among the National Institute for Occupational Safety and Health, the Occupational Safety and Health Administration, the United States Coast Guard, and the United States Environmental Protection Agency, Guidance for Worker Protection During Hazardous Waste Site Investigations and Clean-up and Hazardous Substance Emergencies. December 18, 1980.
6. National Priorities List, 1st Edition, October 1984; U.S. Environmental Protection Agency, Revised periodically.
7. The Decontamination of Response Personnel, Field Standard Operating Procedures (F.S.O.P.) 7; U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Hazardous Response Support Division, December 1984.
8. Preparation of a Site Safety Plan, Field Standard Operating Procedures (F.S.O.P.) 9; U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Hazardous Response Support Division, April 1985.
9. Standard Operating Safety Guidelines; U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Hazardous Response Support Division, Environmental Response Team; November 1984.
10. Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities, National Institute for Occupational Safety and Health (NIOSH), Occupational Safety and Health Administration (OSHA), U.S. Coast Guard (USCG), and Environmental Protection Agency (EPA); October 1985.
11. Protecting Health and Safety at Hazardous Waste Sites: An Overview, U.S. Environmental Protection Agency, EPA/625/9-85/006; September 1985.
12. Hazardous Waste Sites and Hazardous Substance Emergencies, NIOSH Worker Bulletin, U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health; December 1982.
13. Personal Protective Equipment for Hazardous Materials Incidents: A Selection Guide; U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health; October 1984.
14. Fire Service Emergency Management Handbook, International Association of Fire Chiefs Foundation, 101 East Holly Avenue, Unit 10B, Sterling, VA 22170, January 1985.
15. Emergency Response Guidebook, U.S Department of Transportation, Washington, DC, 1987.
16. Report to the Congress on Hazardous Materials Training, Planning and Preparedness, Federal Emergency Management Agency, Washington, DC, July 1986.
17. Workbook for Fire Command, Alan V. Brunacini and J. David Beageron, National Fire Protection Association, Batterymarch Park, Quincy, MA 02269, 1985.
18. Fire Command, Alan V. Brunacini, National Fire Protection Association, Batterymarch Park,, Quincy, MA 02269, 1985.
19. Incident Command System, Fire Protection Publications, Oklahoma State University, Stillwater, OK 74078, 1983.
20. Site Emergency Response Planning, Chemical Manufacturers Association, Washington, DC 20037, 1986.
21. Hazardous Materials Emergency Planning Guide, NRT-1, Environmental Protection Agency, Washington, DC, March 1987.
22. Community Teamwork: Working Together to Promote Hazardous Materials Transportation Safety. U.S. Department of Transportation, Washington, DC, May 1983.
23. Disaster Planning Guide for Business and Industry, Federal Emergency Management Agency, Publication No. FEMA 141, August 1987.
Appendix E to § 1910.120—Training Curriculum Guidelines
The following non-mandatory general criteria may be used for assistance in developing site-specific training curriculum used to meet the training requirements of 29 CFR 1910.120(e); 29 CFR 1910.120(p)(7), (p)(8)(iii); and 29 CFR 1910.120(q)(6), (q)(7), and (q)(8). These are generic guidelines and they are not presented as a complete training curriculum for any specific employer. Site-specific training programs must be developed on the basis of a needs assessment of the hazardous waste site, RCRA/TSDF, or emergency response operation in accordance with 29 CFR 1910.120.
It is noted that the legal requirements are set forth in the regulatory text of § 1910.120. The guidance set forth here presents a highly effective program that in the areas covered would meet or exceed the regulatory requirements. In addition, other approaches could meet the regulatory requirements.
Suggested General Criteria
Definitions:
“Competent” means possessing the skills, knowledge, experience, and judgment to perform assigned tasks or activities satisfactorily as determined by the employer.
“Demonstration” means the showing by actual use of equipment or procedures.
“Hands-on training” means training in a simulated work environment that permits each student to have experience performing tasks, making decisions, or using equipment appropriate to the job assignment for which the training is being conducted.
“Initial training” means training required prior to beginning work.
“Lecture” means an interactive discourse with a class lead by an instructor.
“Proficient” means meeting a stated level of achievement.
“Site-specific” means individual training directed to the operations of a specific job site.
“Training hours” means the number of hours devoted to lecture, learning activities, small group work sessions, demonstration, evaluations, or hands-on experience.
Suggested core criteria:
1. Training facility. The training facility should have available sufficient resources, equipment, and site locations to perform didactic and hands-on training when appropriate. Training facilities should have sufficient organization, support staff, and services to conduct training in each of the courses offered.
2. Training Director. Each training program should be under the direction of a training director who is responsible for the program. The Training Director should have a minimum of two years of employee education experience.
3. Instructors. Instructors should be deem competent on the basis of previous documented experience in their area of instruction, successful completion of a “train-the-trainer” program specific to the topics they will teach, and an evaluation of instructional competence by the Training Director.
Instructors should be required to maintain professional competency by participating in continuing education or professional development programs or by completing successfully an annual refresher course and having an annual review by the Training Director.
The annual review by the Training Director should include observation of an instructor's delivery, a review of those observations with the trainer, and an analysis of any instructor or class evaluations completed by the students during the previous year.
4. Course materials. The Training Director should approve all course materials to be used by the training provider. Course materials should be reviewed and updated at least annually. Materials and equipment should be in good working order and maintained properly.
All written and audio-visual materials in training curricula should be peer reviewed by technically competent outside reviewers or by a standing advisory committee.
Reviews should possess expertise in the following disciplines were applicable: occupational health, industrial hygiene and safety, chemical/environmental engineering, employee education, or emergency response. One or more of the peer reviewers should be an employee experienced in the work activities to which the training is directed.
5. Students. The program for accepting students should include:
a. Assurance that the student is or will be involved in work where chemical exposures are likely and that the student possesses the skills necessary to perform the work.
b. A policy on the necessary medical clearance.
6. Ratios. Student-instructor ratios should not exceed 30 students per instructor. Hands-on activity requiring the use of personal protective equipment should have the following student-instructor ratios. For Level C or Level D personal protective equipment the ratio should be 10 students per instructor. For Level A or Level B personal protective equipment the ratio should be 5 students per instructor.
7. Proficiency assessment. Proficiency should be evaluated and documented by the use of a written assessment and a skill demonstration selected and developed by the Training Director and training staff. The assessment and demonstration should evaluate the knowledge and individual skills developed in the course of training. The level of minimum achievement necessary for proficiency shall be specified in writing by the Training Director.
If a written test is used, there should be a minimum of 50 questions. If a written test is used in combination with a skills demonstration, a minimum of 25 questions should be used. If a skills demonstration is used, the tasks chosen and the means to rate successful completion should be fully documented by the Training Director.
The content of the written test or of the skill demonstration shall be relevant to the objectives of the course. The written test and skill demonstration should be updated as necessary to reflect changes in the curriculum and any update should be approved by the Training Director.
The proficiency assessment methods, regardless of the approach or combination of approaches used, should be justified, documented and approved by the Training Director.
The proficiency of those taking the additional courses for supervisors should be evaluated and documented by using proficiency assessment methods acceptable to the Training Director. These proficiency assessment methods must reflect the additional responsibilities borne by supervisory personnel in hazardous waste operations or emergency response.
8. Course certificate. Written documentation should be provided to each student who satisfactorily completes the training course. The documentation should include:
a. Student's name.
b. Course title.
c. Course date.
d. Statement that the student has successfully completed the course.
e. Name and address of the training provider.
f. An individual identification number for the certificate.
g. List of the levels of personal protective equipment used by the student to complete the course.
This documentation may include a certificate and an appropriate wallet-sized laminated card with a photograph of the student and the above information. When such course certificate cards are used, the individual identification number for the training certificate should be shown on the card.
9. Recordkeeping. Training providers should maintain records listing the dates courses were presented, the names of the individual course attenders, the names of those students successfully completing each course, and the number of training certificates issued to each successful student. These records should be maintained for a minimum of five years after the date an individual participated in a training program offered by the training provider. These records should be available and provided upon the student's request or as mandated by law.
10. Program quality control. The Training Director should conduct or direct an annual written audit of the training program. Program modifications to address deficiencies, if any, should be documented, approved, and implemented by the training provider. The audit and the program modification documents should be maintained at the training facility.
Suggested Program Quality Control Criteria
Factors listed here are suggested criteria for determining the quality and appropriateness of employee health and safety training for hazardous waste operations and emergency response.
A. Training Plan.
Adequacy and appropriateness of the training program's curriculum development, instructor training, distribution of course materials, and direct student training should be considered, including
1. The duration of training, course content, and course schedules/agendas;
2. The different training requirements of the various target populations, as specified in the appropriate generic training curriculum;
3. The process for the development of curriculum, which includes appropriate technical input, outside review, evaluation, program pretesting.
4. The adequate and appropriate inclusion of hands-on, demonstration, and instruction methods;
5. Adequate monitoring of student safety, progress, and performance during the training.
B. Program management, Training Director, staff, and consultants.
Adequacy and appropriateness of staff performance and delivering an effective training program should be considered, including
1. Demonstration of the training director's leadership in assuring quality of health and safety training.
2. Demonstration of the competency of the staff to meet the demands of delivering high quality hazardous waste employee health and safety training.
3. Organization charts establishing clear lines of authority.
4. Clearly defined staff duties including the relationship of the training staff to the overall program.
5. Evidence that the training organizational structure suits the needs of the training program.
6. Appropriateness and adequacy of the training methods used by the instructors.
7. Sufficiency of the time committed by the training director and staff to the training program.
8. Adequacy of the ratio of training staff to students.
9. Availability and commitment of the training program of adequate human and equipment resources in the areas of
a. Health effects,
b. Safety,
c. Personal protective equipment (PPE),
d. Operational procedures,
e. Employee protection practices/procedures.
10. Appropriateness of management controls.
11. Adequacy of the organization and appropriate resources assigned to assure appropriate training.
12. In the case of multiple-site training programs, adequacy of satellite centers management.
C. Training facilities and resources.
Adequacy and appropriateness of the facilities and resources for supporting the training program should be considered, including,
1. Space and equipment to conduct the training.
2. Facilities for representative hands-on training.
3. In the case of multiple-site programs, equipment and facilities at the satellite centers.
4. Adequacy and appropriateness of the quality control and evaluations program to account for instructor performance.
5. Adequacy and appropriateness of the quality control and evaluation program to ensure appropriate course evaluation, feedback, updating, and corrective action.
6. Adequacy and appropriateness of disciplines and expertise being used within the quality control and evaluation program.
7. Adequacy and appropriateness of the role of student evaluations to provide feedback for training program improvement.
D. Quality control and evaluation.
Adequacy and appropriateness of quality control and evaluation plans for training programs should be considered, including:
1. A balanced advisory committee and/or competent outside reviewers to give overall policy guidance;
2. Clear and adequate definition of the composition and active programmatic role of the advisory committee or outside reviewers.
3. Adequacy of the minutes or reports of the advisory committee or outside reviewers' meetings or written communication.
4. Adequacy and appropriateness of the quality control and evaluations program to account for instructor performance.
5. Adequacy and appropriateness of the quality control and evaluation program to ensure appropriate course evaluation, feedback, updating, and corrective action.
6. Adequacy and appropriateness of disciplines and expertise being used within the quality control and evaluation program.
7. Adequacy and appropriateness of the role of student evaluations to provide feedback for training program improvement.
E. Students
Adequacy and appropriateness of the program for accepting students should be considered, including
1. Assurance that the student already possess the necessary skills for their job, including necessary documentation.
2. Appropriateness of methods the program uses to ensure that recruits are capable of satisfactorily completing training.
3. Review and compliance with any medical clearance policy.
F. Institutional Environment and Administrative Support
The adequacy and appropriateness of the institutional environment and administrative support system for the training program should be considered, including
1. Adequacy of the institutional commitment to the employee training program.
2. Adequacy and appropriateness of the administrative structure and administrative support.
G. Summary of Evaluation Questions
Key questions for evaluating the quality and appropriateness of an overall training program should include the following:
1. Are the program objectives clearly stated?
2. Is the program accomplishing its objectives?
3. Are appropriate facilities and staff available?
4. Is there an appropriate mix of classroom, demonstration, and hands-on training?
5. Is the program providing quality employee health and safety training that fully meets the intent of regulatory requirements?
6. What are the program's main strengths?
7. What are the program's main weaknesses?
8. What is recommended to improve the program?
9. Are instructors instructing according to their training outlines?
10. Is the evaluation tool current and appropriate for the program content?
11. Is the course material current and relevant to the target group?
Suggested Training Curriculum Guidelines
The following training curriculum guidelines are for those operations specifically identified in 29 CFR 1910.120 as requiring training. Issues such as qualifications of instructors, training certification, and similar criteria appropriate to all categories of operations addressed in 1910.120 have been covered in the preceding section and are not re-addressed in each of the generic guidelines. Basic core requirements for training programs that are addressed include
1. General Hazardous Waste Operations
2. RCRA operations—Treatment, storage, and disposal facilities.
3. Emergency Response.
A. General Hazardous Waste Operations and Site-specific Training
1. Off-site training. Training course content for hazardous waste operations, required by 29 CFR 1910.120(e), should include the following topics or procedures:
a. Regulatory knowledge.
b. Technical knowledge.
c. Technical skills.
d. Additional suggested items.
2. Refresher training.
The 8-hour annual refresher training required in 29 CFR 1910.120(e)(8) should be conducted by qualified training providers. Refresher training should include at a minimum the following topics and procedures:
3. On-site training.
a. The employer should provide employees engaged in hazardous waste site activities with information and training prior to initial assignment into their work area, as follows:
b. The employer should provide hazardous waste employees information and training and should provide a review and access to the site safety and plan as follows:
c. The employer should provide hazardous waste employees information and training on personal protective equipment used at the site, such as the following:
to be used based upon known or anticipated site hazards.
limitations of materials and construction; limitations during temperature extremes, heat stress, and other appropriate medical considerations; use and limitations of respirator equipment as well as documentation procedures as outlined in 29 CFR 1910.134.
inspection procedures prior to, during, and after use.
donning and doffing procedures.
decontamination and disposal procedures.
maintenance and storage.
d. The employer should instruct the employee about the site medical surveillance program relative to the particular site, including
e. The employees will review and discuss the site safety plan as part of the training program. The location of the site safety plan and all written programs should be discussed with employees including a discussion of the mechanisms for access, review, and references described.
B. RCRA Operations Training for Treatment, Storage and Disposal Facilities.
1. As a minimum, the training course required in 29 CFR 1910.120 (p) should include the following topics:
2. The individual employer should provide hazardous waste employees with information and training prior to an employee's initial assignment into a work area. The training and information should cover the following topics:
C. Emergency response training.
Federal OSHA standards in 29 CFR 1910.120(q) are directed toward private sector emergency responders. Therefore, the guidelines provided in this portion of the appendix are directed toward that employee population. However, they also impact indirectly through State OSHA or USEPA regulations some public sector emergency responders. Therefore, the guidelines provided in this portion of the appendix may be applied to both employee populations.
States with OSHA state plans must cover their employees with regulations at least as effective as the Federal OSHA standards. Public employees in states without approved state OSHA programs covering hazardous waste operations and emergency response are covered by the U.S. EPA under 40 CFR 311, a regulation virtually identical to § 1910.120.
Since this is a non-mandatory appendix and therefore not an enforceable standard, OSHA recommends that those employers, employees or volunteers in public sector emergency response organizations outside Federal OSHA jurisdiction consider the following criteria in developing their own training programs. A unified approach to training at the community level between emergency response organizations covered by Federal OSHA and those not covered directly by Federal OSHA can help ensure an effective community response to the release or potential release of hazardous substances in the community.
a. General considerations.
Emergency response organizations are required to consider the topics listed in § 1910.120(q)(6). Emergency response organizations may use some or all of the following topics to supplement those mandatory topics when developing their response training programs. Many of the topics would require an interaction between the response provider and the individuals responsible for the site where the response would be expected.
b. Suggested criteria for specific courses.
Department of Transportation's Emergency Response Guidebook (ERG) and familiarization with OSHA standard 29 CFR 1910.1201.
Department of Transportation's Emergency Response Guidebook (ERG), manufacturer safety data sheets, CHEMTREC/CANUTEC, shipper or manufacturer contacts, and other relevant sources of information addressing hazardous substance releases. Familiarization with OSHA standard 29 CFR 1910.1201.
The incident commander is the individual who, at any one time, is responsible for and in control of the response effort. This individual is the person responsible for the direction and coordination of the response effort. An incident commander's position should be occupied by the most senior, appropriately trained individual present at the response site. Yet, as necessary and appropriate by the level of response provided, the position may be occupied by many individuals during a particular response as the need for greater authority, responsibility, or training increases. It is possible for the first responder at the awareness level to assume the duties of incident commander until a more senior and appropriately trained individual arrives at the response site.
Therefore, any emergency responder expected to perform as an incident commander should be trained to fulfill the obligations of the position at the level of response they will be providing including the following:
[54 FR 9317, Mar. 6, 1989, as amended at 55 FR 14073, Apr. 13, 1990; 56 FR 15832, Apr. 18, 1991; 59 FR 43270, Aug. 22, 1994; 61 FR 9238, Mar. 7, 1996; 67 FR 67964, Nov. 7, 2002; 71 FR 16672, Apr. 3, 2006; 76 FR 80738, Dec. 27, 2011; 77 FR 17776, Mar. 26, 2012; 78 FR 9313, Feb. 8, 2013; 84 FR 21597, May 14, 2019]
This section lists the paragraph headings contained in §§ 1910.123 through 1910.126.
§ 1910.123 Dipping and coating operations: Coverage and definitions.
§ 1910.124 General requirements for dipping and coating operations.
§ 1910.125 Additional requirements for dipping and coating operations that use flammable or combustible liquids.
§ 1910.126 Additional requirements for special dipping and coating operations.
Adjacent area means any area within 20 feet (6.1 m) of a vapor area that is not separated from the vapor area by tight partitions.
Approved means that the equipment so designated is listed or approved by a nationally recognized testing laboratory, as defined by § 1910.7.
Autoignition temperature means the minimum temperature required to cause self-sustained combustion, independent of any other source of heat.
Dip tank means a container holding a liquid other than water and that is used for dipping or coating. An object may be immersed (or partially immersed) in a dip tank or it may be suspended in a vapor coming from the tank.
Flammable liquid means any liquid having a flashpoint at or below 199.4 °F (93 °C).
Flashpoint means the minimum temperature at which a liquid gives off a vapor in sufficient concentration to ignite if tested in accordance with the test methods in Appendix B to § 1910.1200—Physical Hazard Criteria.
Lower flammable limit (LFL) means the lowest concentration of a material that will propagate a flame. The LFL is usually expressed as a percent by volume of the material in air (or other oxidant).
Vapor area means any space containing a dip tank, including its drain boards, associated drying or conveying equipment, and any surrounding area where the vapor concentration exceeds 25% of the LFL of the liquid in the tank.
You means the employer, as defined by the Occupational Safety and Health Act of 1970 (29 U.S.C. 651 et seq. ).
[64 FR 13909, Mar. 23, 1999, as amended at 77 FR 17777, Mar. 26, 2012]
Z9.2-1979, Fundamentals Governing the Design and Operation of Local Exhaust Systems;
Standard for Dip Tanks Containing Flammable or Combustible Liquids;
A Manual of Recommended Practice” (22nd ed., 1995); or
Z9.1-1971, Practices for Ventilation and Operation of Open-Surface Tanks, and NFPA 34-1966, Standard for Dip Tanks Containing Flammable or Combustible Liquids.
[64 FR 13909, Mar. 23, 1999, as amended at 77 FR 17777, Mar. 26, 2012]
If you use flammable liquids, you must comply with the requirements of this section as well as the requirements of §§ 1910.123, 1910.124, and 1910.126, as applicable.
| You must also comply with this section if: | And: |
|---|---|
| • The flashpoint of the liquid is 199.4 °F (93 °C) or above | • The liquid is heated as part of the operation; or • A heated object is placed in the liquid. |
[64 FR 13909, Mar. 23, 1999, as amended at 77 FR 17777, Mar. 26, 2012]
In addition to the requirements in §§ 1910.123 through 1910.125, you must comply with any requirement in this section that applies to your operation.
[64 FR 13909, Mar. 23, 1999, as amended at 77 FR 17777, Mar. 26, 2012]
Protective equipment, including personal protective equipment for eyes, face, head, and extremities, protective clothing, respiratory devices, and protective shields and barriers, shall be provided, used, and maintained in a sanitary and reliable condition wherever it is necessary by reason of hazards of processes or environment, chemical hazards, radiological hazards, or mechanical irritants encountered in a manner capable of causing injury or impairment in the function of any part of the body through absorption, inhalation or physical contact.
Where employees provide their own protective equipment, the employer shall be responsible to assure its adequacy, including proper maintenance, and sanitation of such equipment.
All personal protective equipment shall be of safe design and construction for the work to be performed.
Defective or damaged personal protective equipment shall not be used.
[39 FR 23502, June 27, 1974, as amended at 59 FR 16334, Apr. 6, 1994; 59 FR 33910, July 1, 1994; 72 FR 64428, Nov. 15, 2007; 76 FR 33606, June 8, 2011; 81 FR 82999, Nov. 18, 2016]
| Filter Lenses for Protection Against Radiant Energy | |||
|---|---|---|---|
| Operations | Electrode Size 1 ⁄ 32 in. | Arc Current | Minimum* Protective Shade |
| Shielded metal arc welding | Less than 3 | Less than 60 | 7 |
| 3-5 | 60-160 | 8 | |
| 5-8 | 160-250 | 10 | |
| More than 8 | 250-550 | 11 | |
| Gas metal arc welding and flux cored arc welding | less than 60 | 7 | |
| 60-160 | 10 | ||
| 160-250 | 10 | ||
| 250-500 | 10 | ||
| Gas Tungsten arc welding | less than 50 | 8 | |
| 50-150 | 8 | ||
| 150-500 | 10 | ||
| Air carbon | (Light) | less than 500 | 10 |
| Arc cutting | (Heavy) | 500-1000 | 11 |
| Plasma arc welding | less than 20 | 6 | |
| 20-100 | 8 | ||
| 100-400 | 10 | ||
| 400-800 | 11 | ||
| Plasma arc cutting | (light)** | less than 300 | 8 |
| (medium)** | 300-400 | 9 | |
| (heavy)** | 400-800 | 10 | |
| Torch brazing | 3 | ||
| Torch soldering | 2 | ||
| Carbon arc welding | 14 |
| Filter Lenses for Protection Against Radiant Energy | |||
|---|---|---|---|
| Operations | Plate thickness—inches | Plate thickness—mm | Minimum* Protective Shade |
| Gas Welding: | |||
| Light | Under 1/8 | Under 3.2 | 4 |
| Medium | 1/8 to 1/2 | 3.2 to 12.7 | 5 |
| Heavy | Over 1/2 | Over 12.7 | 6 |
| Oxygen cutting: | |||
| Light | Under 1 | Under 25 | 3 |
| Medium | 1 to 6 | 25 to 150 | 4 |
| Heavy | Over 6 | Over 150 | 5 |
| * As a rule of thumb, start with a shade that is too dark to see the weld zone. Then go to a lighter shade which gives sufficient view of the weld zone without going below the minimum. In oxyfuel gas welding or cutting where the torch produces a high yellow light, it is desirable to use a filter lens that absorbs the yellow or sodium line in the visible light of the (spectrum) operation. | |||
| ** These values apply where the actual arc is clearly seen. Experience has shown that lighter filters may be used when the arc is hidden by the workpiece. |
Z87.1-2010, Occupational and Educational Personal Eye and Face Protection Devices, incorporated by reference in § 1910.6;
Z87.1-2003, Occupational and Educational Personal Eye and Face Protection Devices, incorporated by reference in § 1910.6; or
Z87.1-1989 (R-1998), Practice for Occupational and Educational Eye and Face Protection, incorporated by reference in § 1910.6;
[59 FR 16360, Apr. 6, 1994; 59 FR 33911, July 1, 1994, as amended at 61 FR 9238, Mar. 7, 1996; 61 FR 19548, May 2, 1996; 74 FR 46356, Sept. 9, 2009; 81 FR 16090, Mar. 25, 2016]
This section applies to General Industry (part 1910), Shipyards (part 1915), Marine Terminals (part 1917), Longshoring (part 1918), and Construction (part 1926).
The following definitions are important terms used in the respiratory protection standard in this section.
Air-purifying respirator means a respirator with an air-purifying filter, cartridge, or canister that removes specific air contaminants by passing ambient air through the air-purifying element.
Assigned protection factor (APF) means the workplace level of respiratory protection that a respirator or class of respirators is expected to provide to employees when the employer implements a continuing, effective respiratory protection program as specified by this section.
Atmosphere-supplying respirator means a respirator that supplies the respirator user with breathing air from a source independent of the ambient atmosphere, and includes supplied-air respirators (SARs) and self-contained breathing apparatus (SCBA) units.
Canister or cartridge means a container with a filter, sorbent, or catalyst, or combination of these items, which removes specific contaminants from the air passed through the container.
Demand respirator means an atmosphere-supplying respirator that admits breathing air to the facepiece only when a negative pressure is created inside the facepiece by inhalation.
Emergency situation means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment that may or does result in an uncontrolled significant release of an airborne contaminant.
Employee exposure means exposure to a concentration of an airborne contaminant that would occur if the employee were not using respiratory protection.
End-of-service-life indicator (ESLI) means a system that warns the respirator user of the approach of the end of adequate respiratory protection, for example, that the sorbent is approaching saturation or is no longer effective.
Escape-only respirator means a respirator intended to be used only for emergency exit.
Filter or air purifying element means a component used in respirators to remove solid or liquid aerosols from the inspired air.
Filtering facepiece (dust mask) means a negative pressure particulate respirator with a filter as an integral part of the facepiece or with the entire facepiece composed of the filtering medium.
Fit factor means a quantitative estimate of the fit of a particular respirator to a specific individual, and typically estimates the ratio of the concentration of a substance in ambient air to its concentration inside the respirator when worn.
Fit test means the use of a protocol to qualitatively or quantitatively evaluate the fit of a respirator on an individual. (See also Qualitative fit test QLFT and Quantitative fit test QNFT.)
Helmet means a rigid respiratory inlet covering that also provides head protection against impact and penetration.
High efficiency particulate air (HEPA) filter means a filter that is at least 99.97% efficient in removing monodisperse particles of 0.3 micrometers in diameter. The equivalent NIOSH 42 CFR 84 particulate filters are the N100, R100, and P100 filters.
Hood means a respiratory inlet covering that completely covers the head and neck and may also cover portions of the shoulders and torso.
Immediately dangerous to life or health (IDLH) means an atmosphere that poses an immediate threat to life, would cause irreversible adverse health effects, or would impair an individual's ability to escape from a dangerous atmosphere.
Interior structural firefighting means the physical activity of fire suppression, rescue or both, inside of buildings or enclosed structures which are involved in a fire situation beyond the incipient stage. (See 29 CFR 1910.155)
Loose-fitting facepiece means a respiratory inlet covering that is designed to form a partial seal with the face.
Maximum use concentration (MUC) means the maximum atmospheric concentration of a hazardous substance from which an employee can be expected to be protected when wearing a respirator, and is determined by the assigned protection factor of the respirator or class of respirators and the exposure limit of the hazardous substance. The MUC can be determined mathematically by multiplying the assigned protection factor specified for a respirator by the required OSHA permissible exposure limit, short-term exposure limit, or ceiling limit. When no OSHA exposure limit is available for a hazardous substance, an employer must determine an MUC on the basis of relevant available information and informed professional judgment.
Negative pressure respirator (tight fitting) means a respirator in which the air pressure inside the facepiece is negative during inhalation with respect to the ambient air pressure outside the respirator.
Oxygen deficient atmosphere means an atmosphere with an oxygen content below 19.5% by volume.
Physician or other licensed health care professional (PLHCP) means an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide, or be delegated the responsibility to provide, some or all of the health care services required by paragraph (e) of this section.
Positive pressure respirator means a respirator in which the pressure inside the respiratory inlet covering exceeds the ambient air pressure outside the respirator.
Powered air-purifying respirator (PAPR) means an air-purifying respirator that uses a blower to force the ambient air through air-purifying elements to the inlet covering.
Pressure demand respirator means a positive pressure atmosphere-supplying respirator that admits breathing air to the facepiece when the positive pressure is reduced inside the facepiece by inhalation.
Qualitative fit test (QLFT) means a pass/fail fit test to assess the adequacy of respirator fit that relies on the individual's response to the test agent.
Quantitative fit test (QNFT) means an assessment of the adequacy of respirator fit by numerically measuring the amount of leakage into the respirator.
Respiratory inlet covering means that portion of a respirator that forms the protective barrier between the user's respiratory tract and an air-purifying device or breathing air source, or both. It may be a facepiece, helmet, hood, suit, or a mouthpiece respirator with nose clamp.
Self-contained breathing apparatus (SCBA) means an atmosphere-supplying respirator for which the breathing air source is designed to be carried by the user.
Service life means the period of time that a respirator, filter or sorbent, or other respiratory equipment provides adequate protection to the wearer.
Supplied-air respirator (SAR) or airline respirator means an atmosphere-supplying respirator for which the source of breathing air is not designed to be carried by the user.
This section means this respiratory protection standard.
Tight-fitting facepiece means a respiratory inlet covering that forms a complete seal with the face.
User seal check means an action conducted by the respirator user to determine if the respirator is properly seated to the face.
This paragraph requires the employer to develop and implement a written respiratory protection program with required worksite-specific procedures and elements for required respirator use. The program must be administered by a suitably trained program administrator. In addition, certain program elements may be required for voluntary use to prevent potential hazards associated with the use of the respirator. The Small Entity Compliance Guide contains criteria for the selection of a program administrator and a sample program that meets the requirements of this paragraph. Copies of the Small Entity Compliance Guide will be available on or about April 8, 1998 from the Occupational Safety and Health Administration's Office of Publications, Room N 3101, 200 Constitution Avenue, NW, Washington, DC, 20210 (202-219-4667).
This paragraph requires the employer to evaluate respiratory hazard(s) in the workplace, identify relevant workplace and user factors, and base respirator selection on these factors. The paragraph also specifies appropriately protective respirators for use in IDLH atmospheres, and limits the selection and use of air-purifying respirators.
Employers must use the assigned protection factors listed in Table 1 to select a respirator that meets or exceeds the required level of employee protection. When using a combination respirator (e.g., airline respirators with an air-purifying filter), employers must ensure that the assigned protection factor is appropriate to the mode of operation in which the respirator is being used.
| Type of respirator 1 2 | Quarter mask | Half mask | Full facepiece | Helmet/hood | Loose-fitting facepiece |
|---|---|---|---|---|---|
| 1. Air-Purifying Respirator | 5 | 3 10 | 50 | ||
| 2. Powered Air-Purifying Respirator (PAPR) | 50 | 1,000 | 4 25/1,000 | 25 | |
| 3. Supplied-Air Respirator (SAR) or Airline Respirator | |||||
| • Demand mode | 10 | 50 | |||
| • Continuous flow mode | 50 | 1,000 | 4 25/1,000 | 25 | |
| • Pressure-demand or other positive-pressure mode | 50 | 1,000 | |||
| 4. Self-Contained Breathing Apparatus (SCBA) | |||||
| • Demand mode | 10 | 50 | 50 | ||
| • Pressure-demand or other positive-pressure mode (e.g., open/closed circuit) | 10,000 | 10,000 | |||
| Notes: | |||||
| 1 Employers may select respirators assigned for use in higher workplace concentrations of a hazardous substance for use at lower concentrations of that substance, or when required respirator use is independent of concentration. | |||||
| 2 The assigned protection factors in Table 1 are only effective when the employer implements a continuing, effective respirator program as required by this section (29 CFR 1910.134), including training, fit testing, maintenance, and use requirements. | |||||
| 3 This APF category includes filtering facepieces, and half masks with elastomeric facepieces. | |||||
| 4 The employer must have evidence provided by the respirator manufacturer that testing of these respirators demonstrates performance at a level of protection of 1,000 or greater to receive an APF of 1,000. This level of performance can best be demonstrated by performing a WPF or SWPF study or equivalent testing. Absent such testing, all other PAPRs and SARs with helmets/hoods are to be treated as loose-fitting facepiece respirators, and receive an APF of 25. | |||||
| 5 These APFs do not apply to respirators used solely for escape. For escape respirators used in association with specific substances covered by 29 CFR 1910 subpart Z, employers must refer to the appropriate substance-specific standards in that subpart. Escape respirators for other IDLH atmospheres are specified by 29 CFR 1910.134 (d)(2)(ii). |
| Altitude (ft.) | Oxygen deficient Atmospheres (% 0 2 ) for which the employer may rely on atmosphere-supplying respirators |
|---|---|
| Less than 3,001 | 16.0-19.5 |
| 3,001-4,000 | 16.4-19.5 |
| 4,001-5,000 | 17.1-19.5 |
| 5,001-6,000 | 17.8-19.5 |
| 6,001-7,000 | 18.5-19.5 |
| 7,001-8,000 1 | 19.3-19.5. |
| 1 Above 8,000 feet the exception does not apply. Oxygen-enriched breathing air must be supplied above 14,000 feet. |
Using a respirator may place a physiological burden on employees that varies with the type of respirator worn, the job and workplace conditions in which the respirator is used, and the medical status of the employee. Accordingly, this paragraph specifies the minimum requirements for medical evaluation that employers must implement to determine the employee's ability to use a respirator.
The employer shall provide a medical evaluation to determine the employee's ability to use a respirator, before the employee is fit tested or required to use the respirator in the workplace. The employer may discontinue an employee's medical evaluations when the employee is no longer required to use a respirator.
In determining the employee's ability to use a respirator, the employer shall:
At a minimum, the employer shall provide additional medical evaluations that comply with the requirements of this section if:
supervisor, or the respirator program administrator informs the employer that an employee needs to be reevaluated;
This paragraph requires that, before an employee may be required to use any respirator with a negative or positive pressure tight-fitting facepiece, the employee must be fit tested with the same make, model, style, and size of respirator that will be used. This paragraph specifies the kinds of fit tests allowed, the procedures for conducting them, and how the results of the fit tests must be used.
may only be used to fit test negative pressure air-purifying respirators that must achieve a fit factor of 100 or less.
This paragraph requires employers to establish and implement procedures for the proper use of respirators. These requirements include prohibiting conditions that may result in facepiece seal leakage, preventing employees from removing respirators in hazardous environments, taking actions to ensure continued effective respirator operation throughout the work shift, and establishing procedures for the use of respirators in IDLH atmospheres or in interior structural firefighting situations.
For all IDLH atmospheres, the employer shall ensure that:
In addition to the requirements set forth under paragraph (g)(3), in interior structural fires, the employer shall ensure that:
This paragraph requires the employer to provide for the cleaning and disinfecting, storage, inspection, and repair of respirators used by employees.
The employer shall provide each respirator user with a respirator that is clean, sanitary, and in good working order. The employer shall ensure that respirators are cleaned and disinfected using the procedures in appendix B-2 of this section, or procedures recommended by the respirator manufacturer, provided that such procedures are of equivalent effectiveness. The respirators shall be cleaned and disinfected at the following intervals:
The employer shall ensure that respirators are stored as follows:
The employer shall ensure that respirators that fail an inspection or are otherwise found to be defective are removed from service, and are discarded or repaired or adjusted in accordance with the following procedures:
This paragraph requires the employer to provide employees using atmosphere-supplying respirators (supplied-air and SCBA) with breathing gases of high purity.
This paragraph requires the employer to provide effective training to employees who are required to use respirators. The training must be comprehensive, understandable, and recur annually, and more often if necessary. This paragraph also requires the employer to provide the basic information on respirators in appendix D of this section to employees who wear respirators when not required by this section or by the employer to do so.
This section requires the employer to conduct evaluations of the workplace to ensure that the written respiratory protection program is being properly implemented, and to consult employees to ensure that they are using the respirators properly.
This section requires the employer to establish and retain written information regarding medical evaluations, fit testing, and the respirator program. This information will facilitate employee involvement in the respirator program, assist the employer in auditing the adequacy of the program, and provide a record for compliance determinations by OSHA.
Records of medical evaluations required by this section must be retained and made available in accordance with 29 CFR 1910.1020.
Paragraphs (d)(3)(i)(A) and (d)(3)(i)(B) of this section become effective November 22, 2006.
Compliance with appendix A, appendix B-1, appendix B-2, appendix C, and appendix D to this section are mandatory.
Appendix A to § 1910.134—Fit Testing Procedures (Mandatory)
Part I. OSHA-Accepted Fit Test Protocols
A. Fit Testing Procedures—General Requirements
The employer shall conduct fit testing using the following procedures. The requirements in this appendix apply to all OSHA-accepted fit test methods, both QLFT and QNFT.
1. The test subject shall be allowed to pick the most acceptable respirator from a sufficient number of respirator models and sizes so that the respirator is acceptable to, and correctly fits, the user.
2. Prior to the selection process, the test subject shall be shown how to put on a respirator, how it should be positioned on the face, how to set strap tension and how to determine an acceptable fit. A mirror shall be available to assist the subject in evaluating the fit and positioning of the respirator. This instruction may not constitute the subject's formal training on respirator use, because it is only a review.
3. The test subject shall be informed that he/she is being asked to select the respirator that provides the most acceptable fit. Each respirator represents a different size and shape, and if fitted and used properly, will provide adequate protection.
4. The test subject shall be instructed to hold each chosen facepiece up to the face and eliminate those that obviously do not give an acceptable fit.
5. The more acceptable facepieces are noted in case the one selected proves unacceptable; the most comfortable mask is donned and worn at least five minutes to assess comfort. Assistance in assessing comfort can be given by discussing the points in the following item A.6. If the test subject is not familiar with using a particular respirator, the test subject shall be directed to don the mask several times and to adjust the straps each time to become adept at setting proper tension on the straps.
6. Assessment of comfort shall include a review of the following points with the test subject and allowing the test subject adequate time to determine the comfort of the respirator:
7. The following criteria shall be used to help determine the adequacy of the respirator fit:
8. The test subject shall conduct a user seal check, either the negative and positive pressure seal checks described in appendix B-1 of this section or those recommended by the respirator manufacturer which provide equivalent protection to the procedures in appendix B-1. Before conducting the negative and positive pressure checks, the subject shall be told to seat the mask on the face by moving the head from side-to-side and up and down slowly while taking in a few slow deep breaths. Another facepiece shall be selected and retested if the test subject fails the user seal check tests.
9. The test shall not be conducted if there is any hair growth between the skin and the facepiece sealing surface, such as stubble beard growth, beard, mustache or sideburns which cross the respirator sealing surface. Any type of apparel which interferes with a satisfactory fit shall be altered or removed.
10. If a test subject exhibits difficulty in breathing during the tests, she or he shall be referred to a physician or other licensed health care professional, as appropriate, to determine whether the test subject can wear a respirator while performing her or his duties.
11. If the employee finds the fit of the respirator unacceptable, the test subject shall be given the opportunity to select a different respirator and to be retested.
12. Exercise regimen. Prior to the commencement of the fit test, the test subject shall be given a description of the fit test and the test subject's responsibilities during the test procedure. The description of the process shall include a description of the test exercises that the subject will be performing. The respirator to be tested shall be worn for at least 5 minutes before the start of the fit test.
13. The fit test shall be performed while the test subject is wearing any applicable safety equipment that may be worn during actual respirator use which could interfere with respirator fit.
14. Test Exercises.
In a normal standing position, without talking, the subject shall breathe normally.
In a normal standing position, the subject shall breathe slowly and deeply, taking caution so as not to hyperventilate.
Standing in place, the subject shall slowly turn his/her head from side to side between the extreme positions on each side. The head shall be held at each extreme momentarily so the subject can inhale at each side.
Standing in place, the subject shall slowly move his/her head up and down. The subject shall be instructed to inhale in the up position (i.e., when looking toward the ceiling).
The subject shall talk out loud slowly and loud enough so as to be heard clearly by the test conductor. The subject can read from a prepared text such as the Rainbow Passage, count backward from 100, or recite a memorized poem or song.
Rainbow Passage
When the sunlight strikes raindrops in the air, they act like a prism and form a rainbow. The rainbow is a division of white light into many beautiful colors. These take the shape of a long round arch, with its path high above, and its two ends apparently beyond the horizon. There is, according to legend, a boiling pot of gold at one end. People look, but no one ever finds it. When a man looks for something beyond reach, his friends say he is looking for the pot of gold at the end of the rainbow.
The test subject shall grimace by smiling or frowning. (This applies only to QNFT testing; it is not performed for QLFT)
The test subject shall bend at the waist as if he/she were to touch his/her toes. Jogging in place shall be substituted for this exercise in those test environments such as shroud type QNFT or QLFT units that do not permit bending over at the waist.
Same as exercise (1).
B. Qualitative Fit Test (QLFT) Protocols
1. General
2. Isoamyl Acetate Protocol
Odor threshold screening, performed without wearing a respirator, is intended to determine if the individual tested can detect the odor of isoamyl acetate at low levels.
3. Saccharin Solution Aerosol Protocol
The entire screening and testing procedure shall be explained to the test subject prior to the conduct of the screening test.
The saccharin taste threshold screening, performed without wearing a respirator, is intended to determine whether the individual being tested can detect the taste of saccharin.
4. Bitrex TM (Denatonium Benzoate) Solution Aerosol Qualitative Fit Test Protocol
The Bitrex TM (Denatonium benzoate) solution aerosol QLFT protocol uses the published saccharin test protocol because that protocol is widely accepted. Bitrex is routinely used as a taste aversion agent in household liquids which children should not be drinking and is endorsed by the American Medical Association, the National Safety Council, and the American Association of Poison Control Centers. The entire screening and testing procedure shall be explained to the test subject prior to the conduct of the screening test.
The Bitrex taste threshold screening, performed without wearing a respirator, is intended to determine whether the individual being tested can detect the taste of Bitrex.
5. Irritant Smoke (Stannic Chloride) Protocol
This qualitative fit test uses a person's response to the irritating chemicals released in the “smoke” produced by a stannic chloride ventilation smoke tube to detect leakage into the respirator.
The person to be tested must demonstrate his or her ability to detect a weak concentration of the irritant smoke.
14. of this appendix shall be performed by the test subject while the respirator seal is being continually challenged by the smoke, directed around the perimeter of the respirator at a distance of six inches.
C. Quantitative Fit Test (QNFT) Protocols
The following quantitative fit testing procedures have been demonstrated to be acceptable: Quantitative fit testing using a non-hazardous test aerosol (such as corn oil, polyethylene glycol 400 [PEG 400], di-2-ethyl hexyl sebacate [DEHS], or sodium chloride) generated in a test chamber, and employing instrumentation to quantify the fit of the respirator; Quantitative fit testing using ambient aerosol as the test agent and appropriate instrumentation (condensation nuclei counter) to quantify the respirator fit; Quantitative fit testing using controlled negative pressure and appropriate instrumentation to measure the volumetric leak rate of a facepiece to quantify the respirator fit.
1. General
2. Generated Aerosol Quantitative Fit Testing Protocol
Aerosol generation, dilution, and measurement systems using particulates (corn oil, polyethylene glycol 400 [PEG 400], di-2-ethyl hexyl sebacate [DEHS] or sodium chloride) as test aerosols shall be used for quantitative fit testing.
The test chamber shall be large enough to permit all test subjects to perform freely all required exercises without disturbing the test agent concentration or the measurement apparatus. The test chamber shall be equipped and constructed so that the test agent is effectively isolated from the ambient air, yet uniform in concentration throughout the chamber.
1
2
3
3. Ambient aerosol condensation nuclei counter (CNC) quantitative fit testing protocol.
The ambient aerosol condensation nuclei counter (CNC) quantitative fit testing (PortaCount®) protocol quantitatively fit tests respirators with the use of a probe. The probed respirator is only used for quantitative fit tests. A probed respirator has a special sampling device, installed on the respirator, that allows the probe to sample the air from inside the mask. A probed respirator is required for each make, style, model, and size that the employer uses and can be obtained from the respirator manufacturer or distributor. The primary CNC instrument manufacturer, TSI Incorporated, also provides probe attachments (TSI mask sampling adapters) that permit fit testing in an employee's own respirator. A minimum fit factor pass level of at least 100 is necessary for a half-mask respirator (elastomeric or filtering facepiece), and a minimum fit factor pass level of at least 500 is required for a full-facepiece elastomeric respirator. The entire screening and testing procedure shall be explained to the test subject prior to the conduct of the screening test.
4. Modified ambient aerosol condensation nuclei counter (CNC) quantitative fit testing protocol for full-facepiece and half-mask elastomeric respirators.
| Exercises 1 | Exercise procedure | Measurement procedure |
|---|---|---|
| Bending Over | The test subject shall bend at the waist, as if going to touch his/her toes for 50 seconds and inhale 2 times at the bottom 2 | A 20 second ambient sample, followed by a 30 second mask sample. |
| Jogging-in-Place | The test subject shall jog in place comfortably for 30 seconds | A 30 second mask sample. |
| Head Side-to-Side | The test subject shall stand in place, slowly turning his/her head from side to side for 30 seconds and inhale 2 times at each extreme 2 | A 30 second mask sample. |
| Head Up-and-Down | The test subject shall stand in place, slowly moving his/her head up and down for 39 seconds and inhale 2 times at each extreme 2 | A 30 second mask sample followed by a 9 second ambient sample. |
| 1 Exercises are listed in the order in which they are to be administered. | ||
| 2 It is optional for test subjects to take additional breaths at other times during this exercise. |
5. Modified ambient aerosol condensation nuclei counter (CNC) quantitative fit testing protocol for filtering facepiece respirators.
| Exercises 1 | Exercise procedure | Measurement procedure |
|---|---|---|
| Bending Over | The test subject shall bend at the waist, as if going to touch his/her toes for 50 seconds and inhale 2 times at the bottom 2 | A 20 second ambient sample, followed by a 30 second mask sample. |
| Talking | The test subject shall talk out loud slowly and loud enough so as to be heard clearly by the test conductor for 30 seconds. He/she will either read from a prepared text such as the Rainbow Passage, count backward from 100, or recite a memorized poem or song | A 30 second mask sample. |
| Head Side-to-Side | The test subject shall stand in place, slowly turning his/her head from side to side for 30 seconds and inhale 2 times at each extreme 2 | A 30 second mask sample. |
| Head Up-and-Down | The test subject shall stand in place, slowly moving his/her head up and down for 39 seconds and inhale 2 times at each extreme 2 | A 30 second mask sample followed by a 9 second ambient sample. |
| 1 Exercises are listed in the order in which they are to be administered. | ||
| 2 It is optional for test subjects to take additional breaths at other times during this exercise. |
6. Controlled negative pressure (CNP) quantitative fit testing protocol.
The CNP protocol provides an alternative to aerosol fit test methods. The CNP fit test method technology is based on exhausting air from a temporarily sealed respirator facepiece to generate and then maintain a constant negative pressure inside the facepiece. The rate of air exhaust is controlled so that a constant negative pressure is maintained in the respirator during the fit test. The level of pressure is selected to replicate the mean inspiratory pressure that causes leakage into the respirator under normal use conditions. With pressure held constant, air flow out of the respirator is equal to air flow into the respirator. Therefore, measurement of the exhaust stream that is required to hold the pressure in the temporarily sealed respirator constant yields a direct measure of leakage air flow into the respirator. The CNP fit test method measures leak rates through the facepiece as a method for determining the facepiece fit for negative pressure respirators. The CNP instrument manufacturer Occupational Health Dynamics of Birmingham, Alabama also provides attachments (sampling manifolds) that replace the filter cartridges to permit fit testing in an employee's own respirator. To perform the test, the test subject closes his or her mouth and holds his/her breath, after which an air pump removes air from the respirator facepiece at a pre-selected constant pressure. The facepiece fit is expressed as the leak rate through the facepiece, expressed as milliliters per minute. The quality and validity of the CNP fit tests are determined by the degree to which the in-mask pressure tracks the test pressure during the system measurement time of approximately five seconds. Instantaneous feedback in the form of a real-time pressure trace of the in-mask pressure is provided and used to determine test validity and quality. A minimum fit factor pass level of 100 is necessary for a half-mask respirator and a minimum fit factor of at least 500 is required for a full facepiece respirator. The entire screening and testing procedure shall be explained to the test subject prior to the conduct of the screening test.
Fit Test Requirements.
Test Exercises.
In a normal standing position, without talking, the subject shall breathe normally for 1 minute. After the normal breathing exercise, the subject needs to hold head straight ahead and hold his or her breath for 10 seconds during the test measurement.
In a normal standing position, the subject shall breathe slowly and deeply for 1 minute, being careful not to hyperventilate. After the deep breathing exercise, the subject shall hold his or her head straight ahead and hold his or her breath for 10 seconds during test measurement.
Standing in place, the subject shall slowly turn his or her head from side to side between the extreme positions on each side for 1 minute. The head shall be held at each extreme momentarily so the subject can inhale at each side. After the turning head side to side exercise, the subject needs to hold head full left and hold his or her breath for 10 seconds during test measurement. Next, the subject needs to hold head full right and hold his or her breath for 10 seconds during test measurement.
Standing in place, the subject shall slowly move his or her head up and down for 1 minute. The subject shall be instructed to inhale in the up position (i.e., when looking toward the ceiling). After the moving head up and down exercise, the subject shall hold his or her head full up and hold his or her breath for 10 seconds during test measurement. Next, the subject shall hold his or her head full down and hold his or her breath for 10 seconds during test measurement.
The subject shall talk out loud slowly and loud enough so as to be heard clearly by the test conductor. The subject can read from a prepared text such as the Rainbow Passage, count backward from 100, or recite a memorized poem or song for 1 minute. After the talking exercise, the subject shall hold his or her head straight ahead and hold his or her breath for 10 seconds during the test measurement.
The test subject shall grimace by smiling or frowning for 15 seconds.
The test subject shall bend at the waist as if he or she were to touch his or her toes for 1 minute. Jogging in place shall be substituted for this exercise in those test environments such as shroud-type QNFT units that prohibit bending at the waist. After the bending over exercise, the subject shall hold his or her head straight ahead and hold his or her breath for 10 seconds during the test measurement.
The test subject shall remove and re-don the respirator within a one-minute period. Then, in a normal standing position, without talking, the subject shall breathe normally for 1 minute. After the normal breathing exercise, the subject shall hold his or her head straight ahead and hold his or her breath for 10 seconds during the test measurement. After the test exercises, the test subject shall be questioned by the test conductor regarding the comfort of the respirator upon completion of the protocol. If it has become unacceptable, another model of a respirator shall be tried.
Test Instrument.
7. Controlled negative pressure (CNP) REDON quantitative fit testing protocol.
| Exercises 1 | Exercise procedure | Measurement procedure |
|---|---|---|
| Facing Forward | Stand and breathe normally, without talking, for 30 seconds | Face forward, while holding breath for 10 seconds. |
| Bending Over | Bend at the waist, as if going to touch his or her toes, for 30 seconds | Face parallel to the floor, while holding breath for 10 seconds |
| Head Shaking | For about three seconds, shake head back and forth vigorously several times while shouting | Face forward, while holding breath for 10 seconds |
| REDON 1 | Remove the respirator mask, loosen all facepiece straps, and then redon the respirator mask | Face forward, while holding breath for 10 seconds. |
| REDON 2 | Remove the respirator mask, loosen all facepiece straps, and then redon the respirator mask again | Face forward, while holding breath for 10 seconds. |
| 1 Exercises are listed in the order in which they are to be administered. |
Where:
N = The number of exercises;
1
2
N
Part II. New Fit Test Protocols
A. Any person may submit to OSHA an application for approval of a new fit test protocol. If the application meets the following criteria, OSHA will initiate a rulemaking proceeding under section 6(b)(7) of the OSH Act to determine whether to list the new protocol as an approved protocol in this appendix A.
B. The application must include a detailed description of the proposed new fit test protocol. This application must be supported by either:
1. A test report prepared by an independent government research laboratory (e.g., Lawrence Livermore National Laboratory, Los Alamos National Laboratory, the National Institute for Standards and Technology) stating that the laboratory has tested the protocol and had found it to be accurate and reliable; or
2. An article that has been published in a peer-reviewed industrial hygiene journal describing the protocol and explaining how test data support the protocol's accuracy and reliability.
C. If OSHA determines that additional information is required before the Agency commences a rulemaking proceeding under this section, OSHA will so notify the applicant and afford the applicant the opportunity to submit the supplemental information. Initiation of a rulemaking proceeding will be deferred until OSHA has received and evaluated the supplemental information.
[59 FR 16362, Apr. 6, 1994, as amended at 61 FR 9238, Mar. 7, 1996; 61 FR 19548, May 2, 1996; 74 FR 46356, Sept. 9, 2009; 77 FR 37598, June 22, 2012]
The employer shall ensure that each affected employee uses protective footwear when working in areas where there is a danger of foot injuries due to falling or rolling objects, or objects piercing the sole, or when the use of protective footwear will protect the affected employee from an electrical hazard, such as a static-discharge or electric-shock hazard, that remains after the employer takes other necessary protective measures.
“Standard Test Methods for Foot Protection,” and ASTM F-2413-2005, “Standard Specification for Performance Requirements for Protective Footwear,” which are incorporated by reference in § 1910.6;
“American National Standard for Personal Protection—Protective Footwear,” which is incorporated by reference in § 1910.6; or
“American National Standard for Personal Protection—Protective Footwear,” which is incorporated by reference in § 1910.6.
[59 FR 16362, Apr. 6, 1994; 59 FR 33911, July 1, 1994, as amended at 61 FR 9238, Mar. 7, 1996; 61 FR 19548, May 2, 1996; 61 FR 21228, May 9, 1996; 74 FR 46356, Sept. 9, 2009; 79 FR 20629, Apr. 11, 2014]
Insulating equipment used for the protection of employees shall be capable of withstanding, without failure, the voltages that may be imposed upon it.
Electrical protective equipment shall be maintained in a safe, reliable condition.
The following specific requirements apply to rubber insulating blankets, rubber insulating covers, rubber insulating line hose, rubber insulating gloves, and rubber insulating sleeves:
swelling, softening, hardening, or becoming sticky or inelastic.
| Class of Equipment | Proof-test Voltage rms V | Maximum proof-test current, mA (gloves only) | |||
|---|---|---|---|---|---|
| 280-mm (11-in) glove | 360-mm (14-in) glove | 410-mm (16-in) glove | 460-mm (18-in) glove | ||
| 00 | 2,500 | 8 | 12 | ||
| 0 | 5,000 | 8 | 12 | 14 | 16 |
| 1 | 10,000 | 14 | 16 | 18 | |
| 2 | 20,000 | 16 | 18 | 20 | |
| 3 | 30,000 | 18 | 20 | 22 | |
| 4 | 40,000 | 22 | 24 |
| Class of equipment | Proof-test voltage |
|---|---|
| 00 | 10,000 |
| 0 | 20,000 |
| 1 | 40,000 |
| 2 | 50,000 |
| 3 | 60,000 |
| 4 | 70,000 |
| Note: The dc voltages listed in this table are not appropriate for proof testing rubber insulating line hose or covers. For this equipment, dc proof tests shall use a voltage high enough to indicate that the equipment can be safely used at the voltages listed in Table I-4. See ASTM D1050-05 (2011) and ASTM D1049-98 (2010) for further information on proof tests for rubber insulating line hose and covers, respectively. |
| Class of glove | AC proof test | DC proof test | ||
|---|---|---|---|---|
| mm | in | mm | in | |
| 00 | 38 | 1.5 | 38 | 1.5 |
| 0 | 38 | 1.5 | 38 | 1.5 |
| 1 | 38 | 1.5 | 51 | 2.0 |
| 2 | 64 | 2.5 | 76 | 3.0 |
| 3 | 89 | 3.5 | 102 | 4.0 |
| 4 | 127 | 5.0 | 153 | 6.0 |
| 1 The water level is given as the clearance from the reinforced edge of the glove to the water line, with a tolerance of ±13 mm. (±0.5 in.). | ||||
| 2 If atmospheric conditions make the specified clearances impractical, the clearances may be increased by a maximum of 25 mm. (1 in.). |
| Class of equipment | Maximum use voltage 1 AC rms | Retest voltage 2 AC rms | Retest voltage 2 DC avg |
|---|---|---|---|
| 00 | 500 | 2,500 | 10,000 |
| 0 | 1,000 | 5,000 | 20,000 |
| 1 | 7,500 | 10,000 | 40,000 |
| 2 | 17,000 | 20,000 | 50,000 |
| 3 | 26,500 | 30,000 | 60,000 |
| 4 | 36,000 | 40,000 | 70,000 |
| 1 The maximum use voltage is the ac voltage (rms) classification of the protective equipment that designates the maximum nominal design voltage of the energized system that may be safely worked. The nominal design voltage is equal to the phase-to-phase voltage on multiphase circuits. However, the phase-to-ground potential is considered to be the nominal design voltage if: | |||
| (1) There is no multiphase exposure in a system area and the voltage exposure is limited to the phase-to-ground potential, or | |||
| (2) The electric equipment and devices are insulated or isolated or both so that the multiphase exposure on a grounded wye circuit is removed. | |||
| 2 The proof-test voltage shall be applied continuously for at least 1 minute, but no more than 3 minutes. |
| Type of equipment | When to test |
|---|---|
| Rubber insulating line hose | Upon indication that insulating value is suspect and after repair. |
| Rubber insulating covers | Upon indication that insulating value is suspect and after repair. |
| Rubber insulating blankets | Before first issue and every 12 months thereafter; 1 upon indication that insulating value is suspect; and after repair. |
| Rubber insulating gloves | Before first issue and every 6 months thereafter; 1 upon indication that insulating value is suspect; after repair; and after use without protectors. |
| Rubber insulating sleeves | Before first issue and every 12 months thereafter; 1 upon indication that insulating value is suspect; and after repair. |
| 1 If the insulating equipment has been electrically tested but not issued for service, the insulating equipment may not be placed into service unless it has been electrically tested within the previous 12 months. |
[79 FR 20629, Apr. 11, 2014]
Employers shall select and require employees to use appropriate hand protection when employees' hands are exposed to hazards such as those from skin absorption of harmful substances; severe cuts or lacerations; severe abrasions; punctures; chemical burns; thermal burns; and harmful temperature extremes.
Employers shall base the selection of the appropriate hand protection on an evaluation of the performance characteristics of the hand protection relative to the task(s) to be performed, conditions present, duration of use, and the hazards and potential hazards identified.
[59 FR 16362, Apr. 6, 1994; 59 FR 33911, July 1, 1994]
This section establishes performance, care, and use criteria for all personal fall protection systems. The employer must ensure that each personal fall protection system used to comply with this part must meet the requirements of this section.
The following definitions apply to this section:
Anchorage means a secure point of attachment for equipment such as lifelines, lanyards, or deceleration devices.
Belt terminal means an end attachment of a window cleaner's positioning system used for securing the belt or harness to a window cleaner's belt anchor.
Body belt means a strap with means both for securing about the waist and for attaching to other components such as a lanyard used with positioning systems, travel restraint systems, or ladder safety systems.
Body harness means straps that secure about the employee in a manner to distribute the fall arrest forces over at least the thighs, pelvis, waist, chest, and shoulders, with a means for attaching the harness to other components of a personal fall protection system.
Carabiner means a connector generally comprised of a trapezoidal or oval shaped body with a closed gate or similar arrangement that may be opened to attach another object and, when released, automatically closes to retain the object.
Competent person means a person who is capable of identifying existing and predictable hazards in any personal fall protection system or any component of it, as well as in their application and uses with related equipment, and who has authorization to take prompt, corrective action to eliminate the identified hazards.
Connector means a device used to couple (connect) parts of the fall protection system together.
D-ring means a connector used:
Deceleration device means any mechanism that serves to dissipate energy during a fall.
Deceleration distance means the vertical distance a falling employee travels from the point at which the deceleration device begins to operate, excluding lifeline elongation and free fall distance, until stopping. It is measured as the distance between the location of an employee's body harness attachment point at the moment of activation (at the onset of fall arrest forces) of the deceleration device during a fall, and the location of that attachment point after the employee comes to a full stop.
Equivalent means alternative designs, equipment, materials, or methods that the employer can demonstrate will provide an equal or greater degree of safety for employees compared to the designs, equipment, materials, or methods specified in the standard.
Free fall means the act of falling before the personal fall arrest system begins to apply force to arrest the fall.
Free fall distance means the vertical displacement of the fall arrest attachment point on the employee's body belt or body harness between onset of the fall and just before the system begins to apply force to arrest the fall. This distance excludes deceleration distance, lifeline and lanyard elongation, but includes any deceleration device slide distance or self-retracting lifeline/lanyard extension before the devices operate and fall arrest forces occur.
Lanyard means a flexible line of rope, wire rope, or strap that generally has a connector at each end for connecting the body belt or body harness to a deceleration device, lifeline, or anchorage.
Lifeline means a component of a personal fall protection system consisting of a flexible line for connection to an anchorage at one end so as to hang vertically (vertical lifeline), or for connection to anchorages at both ends so as to stretch horizontally (horizontal lifeline), and serves as a means for connecting other components of the system to the anchorage.
Personal fall arrest system means a system used to arrest an employee in a fall from a walking-working surface. It consists of a body harness, anchorage, and connector. The means of connection may include a lanyard, deceleration device, lifeline, or a suitable combination of these.
Personal fall protection system means a system (including all components) an employer uses to provide protection from falling or to safely arrest an employee's fall if one occurs. Examples of personal fall protection systems include personal fall arrest systems, positioning systems, and travel restraint systems.
Positioning system (work-positioning system) means a system of equipment and connectors that, when used with a body harness or body belt, allows an employee to be supported on an elevated vertical surface, such as a wall or window sill, and work with both hands free. Positioning systems also are called “positioning system devices” and “work-positioning equipment.”
Qualified describes a person who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience has successfully demonstrated the ability to solve or resolve problems relating to the subject matter, the work, or the project.
Rope grab means a deceleration device that travels on a lifeline and automatically, by friction, engages the lifeline and locks so as to arrest the fall of an employee. A rope grab usually employs the principle of inertial locking, cam/lever locking, or both.
Safety factor means the ratio of the design load and the ultimate strength of the material.
Self-retracting lifeline/lanyard means a deceleration device containing a drum-wound line that can be slowly extracted from, or retracted onto, the drum under slight tension during normal movement by the employee. At the onset of a fall, the device automatically locks the drum and arrests the fall.
Snaphook means a connector comprised of a hook-shaped body with a normally closed gate, or similar arrangement that may be manually opened to permit the hook to receive an object. When released, the snaphook automatically closes to retain the object. Opening a snaphook requires two separate actions. Snaphooks are generally one of two types:
Travel restraint (tether) line means a rope or wire rope used to transfer forces from a body support to an anchorage or anchorage connector in a travel restraint system.
Travel restraint system means a combination of an anchorage, anchorage connector, lanyard (or other means of connection), and body support that an employer uses to eliminate the possibility of an employee going over the edge of a walking-working surface.
Window cleaner's belt means a positioning belt that consists of a waist belt, an integral terminal runner or strap, and belt terminals.
Window cleaner's belt anchor (window anchor) means specifically designed fall-preventing attachment points permanently affixed to a window frame or to a building part immediately adjacent to the window frame, for direct attachment of the terminal portion of a window cleaner's belt.
Window cleaner's positioning system means a system which consists of a window cleaner's belt secured to window anchors.
Work-positioning system (see Positioning system in this paragraph (b)).
The employer must ensure that personal fall protection systems meet the following requirements. Additional requirements for personal fall arrest systems and positioning systems are contained in paragraphs (d) and (e) of this section, respectively.
In addition to the general requirements in paragraph (c) of this section, the employer must ensure that personal fall arrest systems:
The employer must ensure that:
Body belts are prohibited as part of a personal fall arrest system.
The employer must ensure that each positioning system meets the following requirements:
All positioning systems, except window cleaners' positioning systems, are capable of withstanding, without failure, a drop test consisting of a 4-foot (1.2-m) drop of a 250-pound (113-kg) weight;
All window cleaners' positioning systems must:
Lineman's body belt and pole strap systems must meet the following tests:
The employer must ensure that window cleaners' positioning systems meet and are used in accordance with the following:
[81 FR 82999, Nov. 18, 2016, as amended at 84 FR 68797, Dec. 17, 2019]
The documents in appendix A provide information which may be helpful in understanding and implementing the standards in Subpart I.
1. Bureau of Labor Statistics (BLS). “Accidents Involving Eye Injuries.” Report 597, Washington, D.C.: BLS, 1980.
2. Bureau of Labor Statistics (BLS). “Accidents Involving Face Injuries.” Report 604, Washington, D.C.: BLS, 1980.
3. Bureau of Labor Statistics (BLS). “Accidents Involving Head Injuries.” Report 605, Washington, D.C.: BLS, 1980.
4. Bureau of Labor Statistics (BLS). “Accidents Involving Foot Injuries.” Report 626, Washington, D.C.: BLS, 1981.
5. National Safety Council. “Accident Facts”, Annual edition, Chicago, IL: 1981.
6. Bureau of Labor Statistics (BLS). “Occupational Injuries and Illnesses in the United States by Industry,” Annual edition, Washington, D.C.: BLS.
7. National Society to Prevent Blindness. “A Guide for Controlling Eye Injuries in Industry,” Chicago, Il: 1982.
[59 FR 16362, Apr. 6, 1994]
This appendix is intended to provide compliance assistance for employers and employees in implementing requirements for a hazard assessment and the selection of personal protective equipment.
1. Controlling hazards. PPE devices alone should not be relied on to provide protection against hazards, but should be used in conjunction with guards, engineering controls, and sound manufacturing practices.
2. Assessment and selection. It is necessary to consider certain general guidelines for assessing the foot, head, eye and face, and hand hazard situations that exist in an occupational or educational operation or process, and to match the protective devices to the particular hazard. It should be the responsibility of the safety officer to exercise common sense and appropriate expertise to accomplish these tasks.
3. Assessment guidelines. In order to assess the need for PPE the following steps should be taken:
a. Survey. Conduct a walk-through survey of the areas in question. The purpose of the survey is to identify sources of hazards to workers and co-workers. Consideration should be given to the basic hazard categories:
b. Sources. During the walk-through survey the safety officer should observe: (a) sources of motion; i.e., machinery or processes where any movement of tools, machine elements or particles could exist, or movement of personnel that could result in collision with stationary objects; (b) sources of high temperatures that could result in burns, eye injury or ignition of protective equipment, etc.; (c) types of chemical exposures; (d) sources of harmful dust; (e) sources of light radiation, i.e., welding, brazing, cutting, furnaces, heat treating, high intensity lights, etc.; (f) sources of falling objects or potential for dropping objects; (g) sources of sharp objects which might pierce the feet or cut the hands; (h) sources of rolling or pinching objects which could crush the feet; (i) layout of workplace and location of co-workers; and (j) any electrical hazards. In addition, injury/accident data should be reviewed to help identify problem areas.
c. Organize data. Following the walk-through survey, it is necessary to organize the data and information for use in the assessment of hazards. The objective is to prepare for an analysis of the hazards in the environment to enable proper selection of protective equipment.
d. Analyze data. Having gathered and organized data on a workplace, an estimate of the potential for injuries should be made. Each of the basic hazards (paragraph 3.a.) should be reviewed and a determination made as to the type, level of risk, and seriousness of potential injury from each of the hazards found in the area. The possibility of exposure to several hazards simultaneously should be considered.
4. Selection guidelines. After completion of the procedures in paragraph 3, the general procedure for selection of protective equipment is to: a) Become familiar with the potential hazards and the type of protective equipment that is available, and what it can do; i.e., splash protection, impact protection, etc.; b) compare the hazards associated with the environment; i.e., impact velocities, masses, projectile shape, radiation intensities, with the capabilities of the available protective equipment; c) select the protective equipment which ensures a level of protection greater than the minimum required to protect employees from the hazards; and d) fit the user with the protective device and give instructions on care and use of the PPE. It is very important that end users be made aware of all warning labels for and limitations of their PPE.
5. Fitting the device. Careful consideration must be given to comfort and fit. PPE that fits poorly will not afford the necessary protection. Continued wearing of the device is more likely if it fits the wearer comfortably. Protective devices are generally available in a variety of sizes. Care should be taken to ensure that the right size is selected.
6. Devices with adjustable features. Adjustments should be made on an individual basis for a comfortable fit that will maintain the protective device in the proper position. Particular care should be taken in fitting devices for eye protection against dust and chemical splash to ensure that the devices are sealed to the face. In addition, proper fitting of helmets is important to ensure that it will not fall off during work operations. In some cases a chin strap may be necessary to keep the helmet on an employee's head. (Chin straps should break at a reasonably low force, however, so as to prevent a strangulation hazard). Where manufacturer's instructions are available, they should be followed carefully.
7. Reassessment of hazards. It is the responsibility of the safety officer to reassess the workplace hazard situation as necessary, by identifying and evaluating new equipment and processes, reviewing accident records, and reevaluating the suitability of previously selected PPE.
8. Selection chart guidelines for eye and face protection. Some occupations (not a complete list) for which eye protection should be routinely considered are: carpenters, electricians, machinists, mechanics and repairers, millwrights, plumbers and pipe fitters, sheet metal workers and tinsmiths, assemblers, sanders, grinding machine operators, lathe and milling machine operators, sawyers, welders, laborers, chemical process operators and handlers, and timber cutting and logging workers. The following chart provides general guidance for the proper selection of eye and face protection to protect against hazards associated with the listed hazard “source” operations.
| Source | Assessment of Hazard | Protection |
|---|---|---|
| IMPACT—Chipping, grinding machining, masonry work, woodworking, sawing, drilling, chiseling, powered fastening, riveting, and sanding | Flying fragments, objects, large chips, particles sand, dirt, etc | Spectacles with side protection, goggles, face shields. See notes (1), (3), (5), (6), (10). For severe exposure, use faceshield. |
| HEAT—Furnace operations, pouring, casting, hot dipping, and welding | Hot sparks | Faceshields, goggles, spectacles with side protection. For severe exposure use faceshield. See notes (1), (2), (3). |
| Splash from molten metals | Faceshields worn over goggles. See notes (1), (2), (3). | |
| High temperature exposure | Screen face shields, reflective face shields. See notes (1), (2), (3). | |
| CHEMICALS—Acid and chemicals handling, degreasing plating | Splash | Goggles, eyecup and cover types. For severe exposure, use face shield. See notes (3), (11). |
| Irritating mists | Special-purpose goggles. | |
| DUST—Woodworking, buffing, general dusty conditions | Nuisance dust | Goggles, eyecup and cover types. See note (8). |
| LIGHT and/or RADIATION— | ||
| Welding: Electric arc | Optical radiation | Welding helmets or welding shields. Typical shades: 10-14. See notes (9), (12) |
| Welding: Gas | Optical radiation | Welding goggles or welding face shield. Typical shades: gas welding 4-8, cutting 3-6, brazing 3-4. See note (9) |
| Cutting, Torch brazing, Torch soldering | Optical radiation | Spectacles or welding face-shield. Typical shades, 1.5-3. See notes (3), (9) |
| Glare | Poor vision | Spectacles with shaded or special-purpose lenses, as suitable. See notes (9), (10). |
| Notes to Eye and Face Protection Selection Chart: | ||
| (1) Care should be taken to recognize the possibility of multiple and simultaneous exposure to a variety of hazards. Adequate protection against the highest level of each of the hazards should be provided. Protective devices do not provide unlimited protection. | ||
| (2) Operations involving heat may also involve light radiation. As required by the standard, protection from both hazards must be provided. | ||
| (3) Faceshields should only be worn over primary eye protection (spectacles or goggles). | ||
| (4) As required by the standard, filter lenses must meet the requirements for shade designations in § 1910.133(a)(5). Tinted and shaded lenses are not filter lenses unless they are marked or identified as such. | ||
| (5) As required by the standard, persons whose vision requires the use of prescription (Rx) lenses must wear either protective devices fitted with prescription (Rx) lenses or protective devices designed to be worn over regular prescription (Rx) eyewear. | ||
| (6) Wearers of contact lenses must also wear appropriate eye and face protection devices in a hazardous environment. It should be recognized that dusty and/or chemical environments may represent an additional hazard to contact lens wearers. | ||
| (7) Caution should be exercised in the use of metal frame protective devices in electrical hazard areas. | ||
| (8) Atmospheric conditions and the restricted ventilation of the protector can cause lenses to fog. Frequent cleansing may be necessary. | ||
| (9) Welding helmets or faceshields should be used only over primary eye protection (spectacles or goggles). | ||
| (10) Non-sideshield spectacles are available for frontal protection only, but are not acceptable eye protection for the sources and operations listed for “impact.” | ||
| (11) Ventilation should be adequate, but well protected from splash entry. Eye and face protection should be designed and used so that it provides both adequate ventilation and protects the wearer from splash entry. | ||
| (12) Protection from light radiation is directly related to filter lens density. See note (4) . Select the darkest shade that allows task performance. |
9. Selection guidelines for head protection. All head protection (helmets) is designed to provide protection from impact and penetration hazards caused by falling objects. Head protection is also available which provides protection from electric shock and burn. When selecting head protection, knowledge of potential electrical hazards is important. Class A helmets, in addition to impact and penetration resistance, provide electrical protection from low-voltage conductors (they are proof tested to 2,200 volts). Class B helmets, in addition to impact and penetration resistance, provide electrical protection from high-voltage conductors (they are proof tested to 20,000 volts). Class C helmets provide impact and penetration resistance (they are usually made of aluminum which conducts electricity), and should not be used around electrical hazards.
Where falling object hazards are present, helmets must be worn. Some examples include: working below other workers who are using tools and materials which could fall; working around or under conveyor belts which are carrying parts or materials; working below machinery or processes which might cause material or objects to fall; and working on exposed energized conductors.
Some examples of occupations for which head protection should be routinely considered are: carpenters, electricians, linemen, mechanics and repairers, plumbers and pipe fitters, assemblers, packers, wrappers, sawyers, welders, laborers, freight handlers, timber cutting and logging, stock handlers, and warehouse laborers.
Beginning with the ANSI Z89.1-1997 standard, ANSI updated the classification system for protective helmets. Prior revisions used type classifications to distinguish between caps and full brimmed hats. Beginning in 1997, Type I designated helmets designed to reduce the force of impact resulting from a blow only to the top of the head, while Type II designated helmets designed to reduce the force of impact resulting from a blow to the top or sides of the head. Accordingly, if a hazard assessment indicates that lateral impact to the head is foreseeable, employers must select Type II helmets for their employees. To improve comprehension and usefulness, the 1997 revision also redesignated the electrical-protective classifications for helmets as follows: “Class G—General”; helmets designed to reduce the danger of contact with low-voltage conductors; “Class E—Electrical”; helmets designed to reduce the danger of contact with conductors at higher voltage levels; and “Class C—Conductive”; helmets that provide no protection against contact with electrical hazards.
10. Selection guidelines for foot protection. Safety shoes and boots which meet the ANSI Z41-1991 Standard provide both impact and compression protection. Where necessary, safety shoes can be obtained which provide puncture protection. In some work situations, metatarsal protection should be provided, and in other special situations electrical conductive or insulating safety shoes would be appropriate.
Safety shoes or boots with impact protection would be required for carrying or handling materials such as packages, objects, parts or heavy tools, which could be dropped; and, for other activities where objects might fall onto the feet. Safety shoes or boots with compression protection would be required for work activities involving skid trucks (manual material handling carts) around bulk rolls (such as paper rolls) and around heavy pipes, all of which could potentially roll over an employee's feet. Safety shoes or boots with puncture protection would be required where sharp objects such as nails, wire, tacks, screws, large staples, scrap metal etc., could be stepped on by employees causing a foot injury. Electrically conductive shoes would be required as a supplementary form of protection for work activities in which there is a danger of fire or explosion from the discharge of static electricity. Electrical-hazard or dielectric footwear would be required as a supplementary form of protection when an employee standing on the ground is exposed to hazardous step or touch potential (the difference in electrical potential between the feet or between the hands and feet) or when primary forms of electrical protective equipment, such as rubber insulating gloves and blankets, do not provide complete protection for an employee standing on the ground.
Some occupations (not a complete list) for which foot protection should be routinely considered are: Shipping and receiving clerks, stock clerks, carpenters, electricians, machinists, mechanics and repairers, plumbers and pipe fitters, structural metal workers, assemblers, drywall installers and lathers, packers, wrappers, craters, punch and stamping press operators, sawyers, welders, laborers, freight handlers, gardeners and grounds-keepers, timber cutting and logging workers, stock handlers and warehouse laborers.
11. Selection guidelines for hand protection. Gloves are often relied upon to prevent cuts, abrasions, burns, and skin contact with chemicals that are capable of causing local or systemic effects following dermal exposure. OSHA is unaware of any gloves that provide protection against all potential hand hazards, and commonly available glove materials provide only limited protection against many chemicals. Therefore, it is important to select the most appropriate glove for a particular application and to determine how long it can be worn, and whether it can be reused.
It is also important to know the performance characteristics of gloves relative to the specific hazard anticipated; e.g., chemical hazards, cut hazards, flame hazards, etc. These performance characteristics should be assessed by using standard test procedures. Before purchasing gloves, the employer should request documentation from the manufacturer that the gloves meet the appropriate test standard(s) for the hazard(s) anticipated.
Other factors to be considered for glove selection in general include:
With respect to selection of gloves for protection against chemical hazards:
12. Cleaning and maintenance. It is important that all PPE be kept clean and properly maintained. Cleaning is particularly important for eye and face protection where dirty or fogged lenses could impair vision.
For the purposes of compliance with § 1910.132 (a) and (b), PPE should be inspected, cleaned, and maintained at regular intervals so that the PPE provides the requisite protection.
It is also important to ensure that contaminated PPE which cannot be decontaminated is disposed of in a manner that protects employees from exposure to hazards.
[59 FR 16362, Apr. 6, 1994, as amended at 74 FR 46357, Sept. 9, 2009; 79 FR 20633, Apr. 11, 2014]
The following information generally applies to all personal fall protection systems and is intended to assist employers and employees comply with the requirements of § 1910.140 for personal fall protection systems.
It is important for employers to plan prior to using personal fall protection systems. Probably the most overlooked component of planning is locating suitable anchorage points. Such planning should ideally be done before the structure or building is constructed so that anchorage points can be used later for window cleaning or other building maintenance.
Before purchasing a personal fall protection system, an employer should insist that the supplier provide information about its test performance (using recognized test methods) so the employer will know that the system meets the criteria in § 1910.140. Otherwise, the employer should test the equipment to ensure that it is in compliance. Appendix D to this subpart contains test methods which are recommended for evaluating the performance of any system. There are some circumstances in which an employer can evaluate a system based on data and calculations derived from the testing of similar systems. Enough information must be available for the employer to demonstrate that its system and the tested system(s) are similar in both function and design.
Ideally, a personal fall protection system is designed, tested, and supplied as a complete system. However, it is common practice for lanyards, connectors, lifelines, deceleration devices, body belts, and body harnesses to be interchanged since some components wear out before others. Employers and employees should realize that not all components are interchangeable. For instance, a lanyard should not be connected between a body harness and a deceleration device of the self-retracting type (unless specifically allowed by the manufacturer) since this can result in additional free fall for which the system was not designed. In addition, positioning components, such as pole straps, ladder hooks and rebar hooks, should not be used in personal fall arrest systems unless they meet the appropriate strength and performance requirements of part 1910 ( e.g., §§ 1910.140, 1910.268 and 1910.269). Any substitution or change to a personal fall protection system should be fully evaluated or tested by a competent person to determine that it meets applicable OSHA standards before the modified system is put in use. Also, OSHA suggests that rope be used according to manufacturers' recommendations, especially if polypropylene rope is used.
As required by §§ 1910.30 and 1910.132, before an employee uses a fall protection system, the employer must ensure that he or she is trained in the proper use of the system. This may include the following: The limits of the system; proper anchoring and tie-off techniques; estimating free fall distance, including determining elongation and deceleration distance; methods of use; and inspection and storage. Careless or improper use of fall protection equipment can result in serious injury or death. Employers and employees should become familiar with the material in this standard and appendix, as well as manufacturers' recommendations, before a system is used. It is important for employees to be aware that certain tie-offs (such as using knots and tying around sharp edges) can reduce the overall strength of a system. Employees also need to know the maximum permitted free fall distance. Training should stress the importance of inspections prior to use, the limitations of the equipment to be used, and unique conditions at the worksite that may be important.
Employers should obtain comprehensive instructions from the supplier or a qualified person as to the system's proper use and application, including, where applicable:
Personal fall protection systems must be inspected before initial use in each workshift. Any component with damage, such as a cut, tear, abrasion, mold, or evidence of undue stretching, an alteration or addition that might affect its effectiveness, damage due to deterioration, fire, acid, or other corrosive damage, distorted hooks or faulty hook springs, tongues that are unfitted to the shoulder of buckles, loose or damaged mountings, non-functioning parts, or wear, or internal deterioration must be removed from service immediately, and should be tagged or marked as unusable, or destroyed. Any personal fall protection system, including components, subjected to impact loading must be removed from service immediately and not used until a competent person inspects the system and determines that it is not damaged and is safe to use for personal fall protection.
As required by § 1910.140(c)(21), when personal fall arrest systems are used, special consideration must be given to rescuing an employee promptly should a fall occur. The availability of rescue personnel, ladders, or other rescue equipment needs to be evaluated since there may be instances in which employees cannot self-rescue ( e.g., employee unconscious or seriously injured). In some situations, equipment allowing employees to rescue themselves after the fall has been arrested may be desirable, such as devices that have descent capability.
Employers and employees should at all times be aware that the strength of a personal fall arrest system is based on its being attached to an anchoring system that can support the system. Therefore, if a means of attachment is used that will reduce the strength of the system (such as an eye-bolt/snaphook anchorage), that component should be replaced by a stronger one that will also maintain the appropriate maximum deceleration characteristics. The following is a listing of some situations in which employers and employees should be especially cautious:
Sliding hitch knots should not be used except in emergency situations. The one-and-one sliding hitch knot should never be used because it is unreliable in stopping a fall. The two-and-two, or three-and-three knots (preferable) may be used in emergency situations; however, care should be taken to limit free fall distances because of reduced lifeline/lanyard strength. OSHA requires that a competent or qualified person inspect each knot in a lanyard or vertical lifeline to ensure it meets the strength requirements in § 1910.140.
Horizontal lifelines, depending on their geometry and angle of sag, may be subjected to greater loads than the impact load imposed by an attached component. When the angle of horizontal lifeline sag is less than 30 degrees, the impact force imparted to the lifeline by an attached lanyard is greatly amplified. For example, with a sag angle of 15 degrees the force amplification is about 2:1, and at 5 degrees sag it is about 6:1. Depending on the angle of sag, and the line's elasticity, the strength of the horizontal lifeline, and the anchorages to which it is attached should be increased a number of times over that of the lanyard. Extreme care should be taken in considering a horizontal lifeline for multiple tie-offs. If there are multiple tie-offs to a horizontal lifeline, and one employee falls, the movement of the falling employee and the horizontal lifeline during arrest of the fall may cause other employees to fall. Horizontal lifeline and anchorage strength should be increased for each additional employee to be tied-off. For these and other reasons, the systems using horizontal lifelines must be designed only by qualified persons. OSHA recommends testing installed lifelines and anchors prior to use. OSHA requires that horizontal lifelines are designed, installed and used under the supervision of a qualified person.
It must be recognized that the strength of an eye-bolt is rated along the axis of the bolt, and that its strength is greatly reduced if the force is applied at right angles to this axis (in the direction of its shear strength). Care should also be exercised in selecting the proper diameter of the eye to avoid creating a roll-out hazard (accidental disengagement of the snaphook from the eye-bolt).
As required by § 1910.140(c)(3), each employee must have a separate lifeline when the lifeline is vertical. If multiple tie-offs to a single lifeline are used, and one employee falls, the movement of the lifeline during the arrest of the fall may pull other employees' lanyards, causing them to fall as well.
As required by § 1910.140(c)(10), the following connections must be avoided unless the locking snaphook or carabiner has been designed for them because they are conditions that can result in rollout:
Employers and employees should always be aware that a system's maximum arresting force is evaluated under normal use conditions established by the manufacturer. OSHA requires that personal fall arrest systems be rigged so an employee cannot free fall in excess of 6 feet (1.8 m). Even a few additional feet of free fall can significantly increase the arresting force on the employee, possibly to the point of causing injury and possibly exceeding the strength of the system. Because of this, the free fall distance should be kept to a minimum, and, as required by § 1910.140(d)(2), must never be greater than 6 feet (1.8 m). To assure this, the tie-off attachment point to the lifeline or anchor should be located at or above the connection point of the fall arrest equipment to the harness. (Otherwise, additional free fall distance is added to the length of the connecting means ( i.e., lanyard)). Tying off to the walking-working surface will often result in a free fall greater than 6 feet (1.8 m). For instance, if a 6-foot (1.8-m) lanyard is used, the total free fall distance will be the distance from the walking-working level to the harness connection plus the 6 feet (1.8 m) of lanyard.
During fall arrest, a lanyard will stretch or elongate, whereas activation of a deceleration device will result in a certain stopping distance. These distances should be available with the lanyard or device's instructions and must be added to the free fall distance to arrive at the total fall distance before an employee is fully stopped. The additional stopping distance may be significant if the lanyard or deceleration device is attached near or at the end of a long lifeline, which may itself add considerable distance due to its own elongation. As required by § 1910.140(d)(2), sufficient distance to allow for all of these factors must also be maintained between the employee and obstructions below, to prevent an injury due to impact before the system fully arrests the fall. In addition, a minimum of 12 feet (3.7 m) of lifeline should be allowed below the securing point of a rope-grab-type deceleration device, and the end terminated to prevent the device from sliding off the lifeline. Alternatively, the lifeline should extend to the ground or the next working level below. These measures are suggested to prevent the employee from inadvertently moving past the end of the lifeline and having the rope grab become disengaged from the lifeline.
In selecting a location for tie-off, employers and employees should consider obstructions in the potential fall path of the employee. Tie-offs that minimize the possibilities of exaggerated swinging should be considered.
[81 FR 83002, Nov. 18, 2016]
This appendix contains test methods for personal fall protection systems which may be used to determine if they meet the system performance criteria specified in paragraphs (d) and (e) of § 1910.140.
Test methods for personal fall arrest systems (paragraph (d) of § 1910.140).
The following sets forth test procedures for personal fall arrest systems as defined in paragraph (d) of § 1910.140.
The test consists of dropping the respective test weight specified in paragraph (d)(2)(i) or (d)(3)(i) of this appendix once. A new, unused system should be used for each test.
A system fails the force test when the recorded maximum arresting force exceeds 2,520 pounds (11.2 kN) when using a body harness.
The maximum elongation and deceleration distance should be recorded during the force test.
The device should be evaluated or tested under the environmental conditions (such as rain, ice, grease, dirt, and type of lifeline) for which the device is designed.
The locking mechanisms of other self-activating-type deceleration devices designed for more than one arrest should lock each of 1,000 times as they would in normal service.
Test methods for positioning systems (paragraph (e) of § 1910.140).
The following sets forth test procedures for positioning systems as defined in paragraph (e) of § 1910.140. The requirements in this appendix for personal fall arrest systems set forth procedures that may be used, along with the procedures listed below, to determine compliance with the requirements for positioning systems.
[81 FR 83002, Nov. 18, 2016]
This section applies to permanent places of employment.
Nonwater carriage toilet facility, means a toilet facility not connected to a sewer.
Number of employees means, unless otherwise specified, the maximum number of employees present at any one time on a regular shift.
Personal service room, means a room used for activities not directly connected with the production or service function performed by the establishment. Such activities include, but are not limited to, first-aid, medical services, dressing, showering, toilet use, washing, and eating.
Potable water means water that meets the standards for drinking purposes of the State or local authority having jurisdiction, or water that meets the quality standards prescribed by the U.S. Environmental Protection Agency's National Primary Drinking Water Regulations (40 CFR 141).
Toilet facility, means a fixture maintained within a toilet room for the purpose of defecation or urination, or both.
Toilet room, means a room maintained within or on the premises of any place of employment, containing toilet facilities for use by employees.
Toxic material means a material in concentration or amount which exceeds the applicable limit established by a standard, such as §§ 1910.1000 and 1910.1001 or, in the absence of an applicable standard, which is of such toxicity so as to constitute a recognized hazard that is causing or is likely to cause death or serious physical harm.
Urinal means a toilet facility maintained within a toilet room for the sole purpose of urination.
Water closet means a toilet facility maintained within a toilet room for the purpose of both defecation and urination and which is flushed with water.
Wet process means any process or operation in a workroom which normally results in surfaces upon which employees may walk or stand becoming wet.
Every enclosed workplace shall be so constructed, equipped, and maintained, so far as reasonably practicable, as to prevent the entrance or harborage of rodents, insects, and other vermin. A continuing and effective extermination program shall be instituted where their presence is detected.
| Number of employees | Minimum number of water closets 1 |
|---|---|
| 1 to 15 | 1 |
| 16 to 35 | 2 |
| 36 to 55 | 3 |
| 56 to 80 | 4 |
| 81 to 110 | 5. |
| 111 to 150 | 6 |
| Over 150 | ( 2 ) |
| 1 Where toilet facilities will not be used by women, urinals may be provided instead of water closets, except that the number of water closets in such cases shall not be reduced to less than 2 ⁄ 3 of the minimum specified. | |
| 2 1 additional fixture for each additional 40 employees. |
Washing facilities shall be maintained in a sanitary condition.
Whenever employees are required by a particular standard to wear protective clothing because of the possibility of contamination with toxic materials, change rooms equipped with storage facilities for street clothes and separate storage facilities for the protective clothing shall be provided.
Where working clothes are provided by the employer and become wet or are washed between shifts, provision shall be made to insure that such clothing is dry before reuse.
This paragraph shall apply only where employees are permitted to consume food or beverages, or both, on the premises.
No employee shall be allowed to consume food or beverages in a toilet room nor in any area exposed to a toxic material.
Receptacles constructed of smooth, corrosion resistant, easily cleanable, or disposable materials, shall be provided and used for the disposal of waste food. The number, size, and location of such receptacles shall encourage their use and not result in overfilling. They shall be emptied not less frequently than once each working day, unless unused, and shall be maintained in a clean and sanitary condition. Receptacles shall be provided with a solid tight-fitting cover unless sanitary conditions can be maintained without use of a cover.
No food or beverages shall be stored in toilet rooms or in an area exposed to a toxic material.
All employee food service facilities and operations shall be carried out in accordance with sound hygienic principles. In all places of employment where all or part of the food service is provided, the food dispensed shall be wholesome, free from spoilage, and shall be processed, prepared, handled, and stored in such a manner as to be protected against contamination.
[39 FR 23502, June 27, 1974, as amended at 40 FR 18446, Apr. 28, 1975; 40 FR 23073, May 28, 1975; 43 FR 49748, Oct. 24, 1978; 63 FR 33466, June 18, 1998; 76 FR 33607, June 8, 2011]
In camps where public sewers are available, all sewer lines and floor drains from buildings shall be connected thereto.
Where electric service is available, each habitable room in a camp shall be provided with at least one ceiling-type light fixture and at least one separate floor- or wall-type convenience outlet. Laundry and toilet rooms and rooms where people congregate shall contain at least one ceiling- or wall-type fixture. Light levels in toilet and storage rooms shall be at least 20 foot-candles 30 inches from the floor. Other rooms, including kitchens and living quarters, shall be at least 30 foot-candles 30 inches from the floor.
Effective measures shall be taken to prevent infestation by and harborage of animal or insect vectors or pests.
[39 FR 23502, June 27, 1974, as amended at 47 FR 14696, Apr. 6, 1982; 49 FR 18295, Apr. 30, 1984; 61 FR 9238, Mar. 7, 1996; 63 FR 33466, June 18, 1998; 70 FR 1141, Jan. 5, 2005; 70 FR 53929, Sept. 13, 2005]
Red shall be the basic color for the identification of:
[Reserved]
Safety cans or other portable containers of flammable liquids having a flash point at or below 80 °F, table containers of flammable liquids (open cup tester), excluding shipping containers, shall be painted red with some additional clearly visible identification either in the form of a yellow band around the can or the name of the contents conspicuously stenciled or painted on the can in yellow. Red lights shall be provided at barricades and at temporary obstructions. Danger signs shall be painted red.
Emergency stop bars on hazardous machines such as rubber mills, wire blocks, flat work ironers, etc., shall be red. Stop buttons or electrical switches which letters or other markings appear, used for emergency stopping of machinery shall be red.
Yellow shall be the basic color for designating caution and for marking physical hazards such as: Striking against, stumbling, falling, tripping, and “caught in between.”
[39 FR 23502, June 27, 1974, as amended at 43 FR 49748, Oct. 24, 1978; 49 FR 5322, Feb. 10, 1984; 61 FR 9239, Mar. 7, 1996; 72 FR 71069, Dec. 14, 2007]
As used in this section, the word sign refers to a surface on prepared for the warning of, or safety instructions of, industrial workers or members of the public who may be exposed to hazards. Excluded from this definition, however, are news releases, displays commonly known as safety posters, and bulletins used for employee education.
Safety instruction signs shall be used where there is a need for general instructions and suggestions relative to safety measures.
All signs shall be furnished with rounded or blunt corners and shall be free from sharp edges, burrs, splinters, or other sharp projections. The ends or heads of bolts or other fastening devices shall be located in such a way that they do not constitute a hazard.
The colors red, black, and white shall be those of opaque glossy samples as specified in Table 1, “Fundamental Specification of Safety Colors for CIE Standard Source ‘C,’ ” of ANSI Z53.1-1967 or in Table 1, “Specification of the Safety Colors for CIE Illuminate C and the CIE 1931, 2 Standard Observer,” of ANSI Z535.1-2006(R2011), incorporated by reference in § 1910.6.
The standard color of the background shall be yellow; and the panel, black with yellow letters. Any letters used against the yellow background shall be black. The colors shall be those of opaque glossy samples as specified in Table 1 of ANSI Z53.1-1967 or Table 1 of ANSI Z535.1-2006(R2011), incorporated by reference in § 1910.6.
The standard color of the background shall be white; and the panel, green with white letters. Any letters used against the white background shall be black. The colors shall be those of opaque glossy samples as specified in Table 1 of ANSI Z53.1-1967 or in Table 1 of ANSI Z535.1-2006(R2011), incorporated by reference in § 1910.6.
This emblem (see fig. J-7) consists of a fluorescent yellow-orange triangle with a dark red reflective border. The yellow-orange fluorescent triangle is a highly visible color for daylight exposure. The reflective border defines the shape of the fluorescent color in daylight and creates a hollow red triangle in the path of motor vehicle headlights at night. The emblem is intended as a unique identification for, and it shall be used only on, vehicles which by design move slowly (25 m.p.h. or less) on the public roads. The emblem is not a clearance marker for wide machinery nor is it intended to replace required lighting or marking of slow-moving vehicles. Neither the color film pattern and its dimensions nor the backing shall be altered to permit use of advertising or other markings. The material, location, mounting, etc., of the emblem shall be in accordance with the American Society of Agricultural Engineers Emblem for Identifying Slow-Moving Vehicles, ASAE R276, 1967, or ASAE S276.2 (ANSI B114.1-1971), which are incorporated by reference as specified in § 1910.6.
The wording of any sign should be easily read and concise. The sign should contain sufficient information to be easily understood. The wording should make a positive, rather than negative suggestion and should be accurate in fact.
The biological hazard warning shall be used to signify the actual or potential presence of a biohazard and to identify equipment, containers, rooms, materials, experimental animals, or combinations thereof, which contain, or are contaminated with, viable hazardous agents. For the purpose of this subparagraph the term “biological hazard,” or “biohazard,” shall include only those infectious agents presenting a risk or potential risk to the well-being of man.
Biological hazard or BIOHAZARD means those infectious agents presenting a risk of death, injury or illness to employees.
Major message means that portion of a tag's inscription that is more specific than the signal word and that indicates the specific hazardous condition or the instruction to be communicated to the employee. Examples include: “High Voltage,” “Close Clearance,” “Do Not Start,” or “Do Not Use” or a corresponding pictograph used with a written text or alone.
Pictograph means a pictorial representation used to identify a hazardous condition or to convey a safety instruction.
Signal word means that portion of a tag's inscription that contains the word or words that are intended to capture the employee's immediate attention.
Tag means a device usually made of card, paper, pasteboard, plastic or other material used to identify a hazardous condition.
Tags shall be used as a means to prevent accidental injury or illness to employees who are exposed to hazardous or potentially hazardous conditions, equipment or operations which are out of the ordinary, unexpected or not readily apparent. Tags shall be used until such time as the identified hazard is eliminated or the hazardous operation is completed. Tags need not be used where signs, guarding or other positive means of protection are being used.
All required tags shall meet the following criteria:
Danger tags shall be used in major hazard situations where an immediate hazard presents a threat of death or serious injury to employees. Danger tags shall be used only in these situations.
Caution tags shall be used in minor hazard situations where a non-immediate or potential hazard or unsafe practice presents a lesser threat of employee injury. Caution tags shall be used only in these situations.
Warning tags may be used to represent a hazard level between “Caution” and “Danger,” instead of the required “Caution” tag, provided that they have a signal word of “Warning,” an appropriate major message, and otherwise meet the general tag criteria of paragraph (f)(4) of this section.
Biological Hazard Symbol Configuration
Other tags may be used in addition to those required by this paragraph (f), or in other situations where this paragraph (f) does not require tags, provided that they do not detract from the impact or visibility of the signal word and major message of any required tag.
Appendixes to § 1910.145( f ), Accident Prevention Tags
This section contains requirements for practices and procedures to protect employees in general industry from the hazards of entry into permit-required confined spaces. This section does not apply to agriculture, to construction, or to shipyard employment (parts 1928, 1926, and 1915 of this chapter, respectively).
Acceptable entry conditions means the conditions that must exist in a permit space to allow entry and to ensure that employees involved with a permit-required confined space entry can safely enter into and work within the space.
Attendant means an individual stationed outside one or more permit spaces who monitors the authorized entrants and who performs all attendant's duties assigned in the employer's permit space program.
Authorized entrant means an employee who is authorized by the employer to enter a permit space.
Blanking or blinding means the absolute closure of a pipe, line, or duct by the fastening of a solid plate (such as a spectacle blind or a skillet blind) that completely covers the bore and that is capable of withstanding the maximum pressure of the pipe, line, or duct with no leakage beyond the plate.
Confined space means a space that:
Double block and bleed means the closure of a line, duct, or pipe by closing and locking or tagging two in-line valves and by opening and locking or tagging a drain or vent valve in the line between the two closed valves.
Emergency means any occurrence (including any failure of hazard control or monitoring equipment) or event internal or external to the permit space that could endanger entrants.
Engulfment means the surrounding and effective capture of a person by a liquid or finely divided (flowable) solid substance that can be aspirated to cause death by filling or plugging the respiratory system or that can exert enough force on the body to cause death by strangulation, constriction, or crushing.
Entry means the action by which a person passes through an opening into a permit-required confined space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant's body breaks the plane of an opening into the space.
Entry permit (permit) means the written or printed document that is provided by the employer to allow and control entry into a permit space and that contains the information specified in paragraph (f) of this section.
Entry supervisor means the person (such as the employer, foreman, or crew chief) responsible for determining if acceptable entry conditions are present at a permit space where entry is planned, for authorizing entry and overseeing entry operations, and for terminating entry as required by this section.
Hazardous atmosphere means an atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue (that is, escape unaided from a permit space), injury, or acute illness from one or more of the following causes:
Hot work permit means the employer's written authorization to perform operations (for example, riveting, welding, cutting, burning, and heating) capable of providing a source of ignition.
Immediately dangerous to life or health (IDLH) means any condition that poses an immediate or delayed threat to life or that would cause irreversible adverse health effects or that would interfere with an individual's ability to escape unaided from a permit space.
Inerting means the displacement of the atmosphere in a permit space by a noncombustible gas (such as nitrogen) to such an extent that the resulting atmosphere is noncombustible.
Isolation means the process by which a permit space is removed from service and completely protected against the release of energy and material into the space by such means as: blanking or blinding; misaligning or removing sections of lines, pipes, or ducts; a double block and bleed system; lockout or tagout of all sources of energy; or blocking or disconnecting all mechanical linkages.
Line breaking means the intentional opening of a pipe, line, or duct that is or has been carrying flammable, corrosive, or toxic material, an inert gas, or any fluid at a volume, pressure, or temperature capable of causing injury.
Non-permit confined space means a confined space that does not contain or, with respect to atmospheric hazards, have the potential to contain any hazard capable of causing death or serious physical harm.
Oxygen deficient atmosphere means an atmosphere containing less than 19.5 percent oxygen by volume.
Oxygen enriched atmosphere means an atmosphere containing more than 23.5 percent oxygen by volume.
Permit-required confined space (permit space) means a confined space that has one or more of the following characteristics:
Permit-required confined space program (permit space program) means the employer's overall program for controlling, and, where appropriate, for protecting employees from, permit space hazards and for regulating employee entry into permit spaces.
Permit system means the employer's written procedure for preparing and issuing permits for entry and for returning the permit space to service following termination of entry.
Prohibited condition means any condition in a permit space that is not allowed by the permit during the period when entry is authorized.
Rescue service means the personnel designated to rescue employees from permit spaces.
Retrieval system means the equipment (including a retrieval line, chest or full-body harness, wristlets, if appropriate, and a lifting device or anchor) used for non-entry rescue of persons from permit spaces.
Testing means the process by which the hazards that may confront entrants of a permit space are identified and evaluated. Testing includes specifying the tests that are to be performed in the permit space.
Under the permit space program required by paragraph (c)(4) of this section, the employer shall:
The entry permit that documents compliance with this section and authorizes entry to a permit space shall identify:
The employer shall ensure that all authorized entrants:
The employer shall ensure that each attendant:
The employer shall ensure that each entry supervisor:
The employer must ensure that such employees successfully complete the training required to establish proficiency as an authorized entrant, as provided by paragraphs (g) and (h) of this section;
Appendixes to § 1910.146—Permit-required Confined Spaces
Appendix B to § 1910.146—Procedures for Atmospheric Testing
Atmospheric testing is required for two distinct purposes: evaluation of the hazards of the permit space and verification that acceptable entry conditions for entry into that space exist.
The atmosphere of a confined space should be analyzed using equipment of sufficient sensitivity and specificity to identify and evaluate any hazardous atmospheres that may exist or arise, so that appropriate permit entry procedures can be developed and acceptable entry conditions stipulated for that space. Evaluation and interpretation of these data, and development of the entry procedure, should be done by, or reviewed by, a technically qualified professional (e.g., OSHA consultation service, or certified industrial hygienist, registered safety engineer, certified safety professional, certified marine chemist, etc.) based on evaluation of all serious hazards.
The atmosphere of a permit space which may contain a hazardous atmosphere should be tested for residues of all contaminants identified by evaluation testing using permit specified equipment to determine that residual concentrations at the time of testing and entry are within the range of acceptable entry conditions. Results of testing (i.e., actual concentration, etc.) should be recorded on the permit in the space provided adjacent to the stipulated acceptable entry condition.
Measurement of values for each atmospheric parameter should be made for at least the minimum response time of the test instrument specified by the manufacturer.
When monitoring for entries involving a descent into atmospheres that may be stratified, the atmospheric envelope should be tested a distance of approximately 4 feet (1.22 m) in the direction of travel and to each side. If a sampling probe is used, the entrant's rate of progress should be slowed to accommodate the sampling speed and detector response.
A test for oxygen is performed first because most combustible gas meters are oxygen dependent and will not provide reliable readings in an oxygen deficient atmosphere. Combustible gasses are tested for next because the threat of fire or explosion is both more immediate and more life threatening, in most cases, than exposure to toxic gasses and vapors. If tests for toxic gasses and vapors are necessary, they are performed last.
Appendix C to § 1910.146—Examples of Permit-required Confined Space Programs
Example 1.
Workplace. Sewer entry.
Potential hazards. The employees could be exposed to the following:
Engulfment.
Presence of toxic gases. Equal to or more than 10 ppm hydrogen sulfide measured as an 8-hour time-weighted average. If the presence of other toxic contaminants is suspected, specific monitoring programs will be developed.
Presence of explosive/flammable gases. Equal to or greater than 10% of the lower flammable limit (LFL).
Oxygen Deficiency. A concentration of oxygen in the atmosphere equal to or less than 19.5% by volume.
A. Entry Without Permit/Attendant
Certification. Confined spaces may be entered without the need for a written permit or attendant provided that the space can be maintained in a safe condition for entry by mechanical ventilation alone, as provided in § 1910.146(c)(5). All spaces shall be considered permit-required confined spaces until the pre-entry procedures demonstrate otherwise. Any employee required or permitted to pre-check or enter an enclosed/confined space shall have successfully completed, -as a minimum, the training as required by the following sections of these procedures. A written copy of operating and rescue procedures as required by these procedures shall be at the work site for the duration of the job. The Confined Space Pre-Entry Check List must be completed by the LEAD WORKER before entry into a confined space. This list verifies completion of items listed below. This check list shall be kept at the job site for duration of the job. If circumstances dictate an interruption in the work, the permit space must be re-evaluated and a new check list must be completed.
Control of atmospheric and engulfment hazards.
Pumps and Lines. All pumps and lines which may reasonably cause contaminants to flow into the space shall be disconnected, blinded and locked out, or effectively isolated by other means to prevent development of dangerous air contamination or engulfment. Not all laterals to sewers or storm drains require blocking. However, where experience or knowledge of industrial use indicates there is a reasonable potential for contamination of air or engulfment into an occupied sewer, then all affected laterals shall be blocked. If blocking and/or isolation requires entry into the space the provisions for entry into a permit- required confined space must be implemented.
Surveillance. The surrounding area shall be surveyed to avoid hazards such as drifting vapors from the tanks, piping, or sewers.
Testing. The atmosphere within the space will be tested to determine whether dangerous air contamination and/or oxygen deficiency exists. Detector tubes, alarm only gas monitors and explosion meters are examples of monitoring equipment that may be used to test permit space atmospheres. Testing shall be performed by the LEAD WORKER who has successfully completed the Gas Detector training for the monitor he will use. The minimum parameters to be monitored are oxygen deficiency, LFL, and hydrogen sulfide concentration. A written record of the pre-entry test results shall be made and kept at the work site for the duration of the job. The supervisor will certify in writing, based upon the results of the pre-entry testing, that all hazards have been eliminated. Affected employees shall be able to review the testing results. The most hazardous conditions shall govern when work is being performed in two adjoining, connecting spaces.
Entry Procedures. If there are no non-atmospheric hazards present and if the pre-entry tests show there is no dangerous air contamination and/or oxygen deficiency within the space and there is no reason to believe that any is likely to develop, entry into and work within may proceed. Continuous testing of the atmosphere in the immediate vicinity of the workers within the space shall be accomplished. The workers will immediately leave the permit space when any of the gas monitor alarm set points are reached as defined. Workers will not return to the area until a SUPERVISOR who has completed the gas detector training has used a direct reading gas detector to evaluate the situation and has determined that it is safe to enter.
Rescue. Arrangements for rescue services are not required where there is no attendant. See the rescue portion of section B., below, for instructions regarding rescue planning where an entry permit is required.
B. Entry Permit Required
Permits. Confined Space Entry Permit. All spaces shall be considered permit-required confined spaces until the pre-entry procedures demonstrate otherwise. Any employee required or permitted to pre-check or enter a permit-required confined space shall have successfully completed, as a minimum, the training as required by the following sections of these procedures. A written copy of operating and rescue procedures as required by these procedures shall be at the work site for the duration of the job. The Confined Space Entry Permit must be completed before approval can be given to enter a permit-required confined space. This permit verifies completion of items listed below. This permit shall be kept at the job site for the duration of the job. If circumstances cause an interruption in the work or a change in the alarm conditions for which entry was approved, a new Confined Space Entry Permit must be completed.
Control of atmospheric and engulfment hazards.
Surveillance. The surrounding area shall be surveyed to avoid hazards such as drifting vapors from tanks, piping or sewers.
Testing. The confined space atmosphere shall be tested to determine whether dangerous air contamination and/or oxygen deficiency exists. A direct reading gas monitor shall be used. Testing shall be performed by the SUPERVISOR who has successfully completed the gas detector training for the monitor he will use. The minimum parameters to be monitored are oxygen deficiency, LFL and hydrogen sulfide concentration. A written record of the pre- entry test results shall be made and kept at the work site for the duration of the job. Affected employees shall be able to review the testing results. The most hazardous conditions shall govern when work is being performed in two adjoining, connected spaces.
Space Ventilation. Mechanical ventilation systems, where applicable, shall be set at 100% outside air. Where possible, open additional manholes to increase air circulation. Use portable blowers to augment natural circulation if needed. After a suitable ventilating period, repeat the testing. Entry may not begin until testing has demonstrated that the hazardous atmosphere has been eliminated.
Entry Procedures. The following procedure shall be observed under any of the following conditions: 1.) Testing demonstrates the existence of dangerous or deficient conditions and additional ventilation cannot reduce concentrations to safe levels; 2.) The atmosphere tests as safe but unsafe conditions can reasonably be expected to develop; 3.) It is not feasible to provide for ready exit from spaces equipped with automatic fire suppression systems and it is not practical or safe to deactivate such systems; or 4.) An emergency exists and it is not feasible to wait for pre-entry procedures to take effect.
All personnel must be trained. A self contained breathing apparatus shall be worn by any person entering the space. At least one worker shall stand by the outside of the space ready to give assistance in case of emergency. The standby worker shall have a self contained breathing apparatus available for immediate use. There shall be at least one additional worker within sight or call of the standby worker. Continuous powered communications shall be maintained between the worker within the confined space and standby personnel.
If at any time there is any questionable action or non- movement by the worker inside, a verbal check will be made. If there is no response, the worker will be moved immediately. Exception: If the worker is disabled due to falling or impact, he/she shall not be removed from the confined space unless there is immediate danger to his/her life. Local fire department rescue personnel shall be notified immediately. The standby worker may only enter the confined space in case of an emergency (wearing the self contained breathing apparatus) and only after being relieved by another worker. Safety belt or harness with attached lifeline shall be used by all workers entering the space with the free end of the line secured outside the entry opening. The standby worker shall attempt to remove a disabled worker via his lifeline before entering the space.
When practical, these spaces shall be entered through side openings—those within 3 1/2 feet (1.07 m) of the bottom. When entry must be through a top opening, the safety belt shall be of the harness type that suspends a person upright and a hoisting device or similar apparatus shall be available for lifting workers out of the space.
In any situation where their use may endanger the worker, use of a hoisting device or safety belt and attached lifeline may be discontinued.
When dangerous air contamination is attributable to flammable and/or explosive substances, lighting and electrical equipment shall be Class 1, Division 1 rated per National Electrical Code and no ignition sources shall be introduced into the area.
Continuous gas monitoring shall be performed during all confined space operations. If alarm conditions change adversely, entry personnel shall exit the confined space and a new confined space permit issued.
Rescue. Call the fire department services for rescue. Where immediate hazards to injured personnel are present, workers at the site shall implement emergency procedures to fit the situation.
Example 2.
Workplace. Meat and poultry rendering plants.
Cookers and dryers are either batch or continuous in their operation. Multiple batch cookers are operated in parallel. When one unit of a multiple set is shut down for repairs, means are available to isolate that unit from the others which remain in operation.
Cookers and dryers are horizontal, cylindrical vessels equipped with a center, rotating shaft and agitator paddles or discs. If the inner shell is jacketed, it is usually heated with steam at pressures up to 150 psig (1034.25 kPa). The rotating shaft assembly of the continuous cooker or dryer is also steam heated.
Potential Hazards. The recognized hazards associated with cookers and dryers are the risk that employees could be:
1. Struck or caught by rotating agitator;
2. Engulfed in raw material or hot, recycled fat;
3. Burned by steam from leaks into the cooker/dryer steam jacket or the condenser duct system if steam valves are not properly closed and locked out;
4. Burned by contact with hot metal surfaces, such as the agitator shaft assembly, or inner shell of the cooker/dryer;
5. Heat stress caused by warm atmosphere inside cooker/dryer;
6. Slipping and falling on grease in the cooker/dryer;
7. Electrically shocked by faulty equipment taken into the cooker/dryer;
8. Burned or overcome by fire or products of combustion; or
9. Overcome by fumes generated by welding or cutting done on grease covered surfaces.
Permits. The supervisor in this case is always present at the cooker/dryer or other permit entry confined space when entry is made. The supervisor must follow the pre-entry isolation procedures described in the entry permit in preparing for entry, and ensure that the protective clothing, ventilating equipment and any other equipment required by the permit are at the entry site.
Control of hazards. Mechanical. Lock out main power switch to agitator motor at main power panel. Affix tag to the lock to inform others that a permit entry confined space entry is in progress.
Engulfment. Close all valves in the raw material blow line. Secure each valve in its closed position using chain and lock. Attach a tag to the valve and chain warning that a permit entry confined space entry is in progress. The same procedure shall be used for securing the fat recycle valve.
Burns and heat stress. Close steam supply valves to jacket and secure with chains and tags. Insert solid blank at flange in cooker vent line to condenser manifold duct system. Vent cooker/dryer by opening access door at discharge end and top center door to allow natural ventilation throughout the entry. If faster cooling is needed, use a portable ventilation fan to increase ventilation. Cooling water may be circulated through the jacket to reduce both outer and inner surface temperatures of cooker/dryers faster. Check air and inner surface temperatures in cooker/dryer to assure they are within acceptable limits before entering, or use proper protective clothing.
Fire and fume hazards. Careful site preparation, such as cleaning the area within 4 inches (10.16 cm) of all welding or torch cutting operations, and proper ventilation are the preferred controls. All welding and cutting operations shall be done in accordance with the requirements of 29 CFR part 1910, subpart Q, OSHA's welding standard. Proper ventilation may be achieved by local exhaust ventilation, or the use of portable ventilation fans, or a combination of the two practices.
Electrical shock. Electrical equipment used in cooker/dryers shall be in serviceable condition.
Slips and falls. Remove residual grease before entering cooker/dryer.
Attendant. The supervisor shall be the attendant for employees entering cooker/dryers.
Permit. The permit shall specify how isolation shall be done and any other preparations needed before making entry. This is especially important in parallel arrangements of cooker/dryers so that the entire operation need not be shut down to allow safe entry into one unit.
Rescue. When necessary, the attendant shall call the fire department as previously arranged.
Example 3.
Workplace. Workplaces where tank cars, trucks, and trailers, dry bulk tanks and trailers, railroad tank cars, and similar portable tanks are fabricated or serviced.
A. During fabrication. These tanks and dry-bulk carriers are entered repeatedly throughout the fabrication process. These products are not configured identically, but the manufacturing processes by which they are made are very similar.
Sources of hazards. In addition to the mechanical hazards arising from the risks that an entrant would be injured due to contact with components of the tank or the tools being used, there is also the risk that a worker could be injured by breathing fumes from welding materials or mists or vapors from materials used to coat the tank interior. In addition, many of these vapors and mists are flammable, so the failure to properly ventilate a tank could lead to a fire or explosion.
Control of hazards.
Welding. Local exhaust ventilation shall be used to remove welding fumes once the tank or carrier is completed to the point that workers may enter and exit only through a manhole. (Follow the requirements of 29 CFR 1910, subpart Q, OSHA's welding standard, at all times.) Welding gas tanks may never be brought into a tank or carrier that is a permit entry confined space.
Application of interior coatings/linings. Atmospheric hazards shall be controlled by forced air ventilation sufficient to keep the atmospheric concentration of flammable materials below 10% of the lower flammable limit (LFL) (or lower explosive limit (LEL), whichever term is used locally). The appropriate respirators are provided and shall be used in addition to providing forced ventilation if the forced ventilation does not maintain acceptable respiratory conditions.
Permits. Because of the repetitive nature of the entries in these operations, an “Area Entry Permit” will be issued for a 1 month period to cover those production areas where tanks are fabricated to the point that entry and exit are made using manholes.
Authorization. Only the area supervisor may authorize an employee to enter a tank within the permit area. The area supervisor must determine that conditions in the tank trailer, dry bulk trailer or truck, etc. meet permit requirements before authorizing entry.
Attendant. The area supervisor shall designate an employee to maintain communication by employer specified means with employees working in tanks to ensure their safety. The attendant may not enter any permit entry confined space to rescue an entrant or for any other reason, unless authorized by the rescue procedure and, and even then, only after calling the rescue team and being relieved by as attendant by another worker.
Communications and observation. Communications between attendant and entrant(s) shall be maintained throughout entry. Methods of communication that may be specified by the permit include voice, voice powered radio, tapping or rapping codes on tank walls, signalling tugs on a rope, and the attendant's observation that work activities such as chipping, grinding, welding, spraying, etc., which require deliberate operator control continue normally. These activities often generate so much noise that the necessary hearing protection makes communication by voice difficult.
Rescue procedures. Acceptable rescue procedures include entry by a team of employee-rescuers, use of public emergency services, and procedures for breaching the tank. The area permit specifies which procedures are available, but the area supervisor makes the final decision based on circumstances. (Certain injuries may make it necessary to breach the tank to remove a person rather than risk additional injury by removal through an existing manhole. However, the supervisor must ensure that no breaching procedure used for rescue would violate terms of the entry permit. For instance, if the tank must be breached by cutting with a torch, the tank surfaces to be cut must be free of volatile or combustible coatings within 4 inches (10.16 cm) of the cutting line and the atmosphere within the tank must be below the LFL.
Retrieval line and harnesses. The retrieval lines and harnesses generally required under this standard are usually impractical for use in tanks because the internal configuration of the tanks and their interior baffles and other structures would prevent rescuers from hauling out injured entrants. However, unless the rescue procedure calls for breaching the tank for rescue, the rescue team shall be trained in the use of retrieval lines and harnesses for removing injured employees through manholes.
B. Repair or service of “used” tanks and bulk trailers.
Sources of hazards. In addition to facing the potential hazards encountered in fabrication or manufacturing, tanks or trailers which have been in service may contain residues of dangerous materials, whether left over from the transportation of hazardous cargoes or generated by chemical or bacterial action on residues of non-hazardous cargoes.
Control of atmospheric hazards. A “used” tank shall be brought into areas where tank entry is authorized only after the tank has been emptied, cleansed (without employee entry) of any residues, and purged of any potential atmospheric hazards.
Welding. In addition to tank cleaning for control of atmospheric hazards, coating and surface materials shall be removed 4 inches (10.16 cm) or more from any surface area where welding or other torch work will be done and care taken that the atmosphere within the tank remains well below the LFL. (Follow the requirements of 29 CFR 1910, subpart Q, OSHA's welding standard, at all times.)
Permits. An entry permit valid for up to 1 year shall be issued prior to authorization of entry into used tank trailers, dry bulk trailers or trucks. In addition to the pre-entry cleaning requirement, this permit shall require the employee safeguards specified for new tank fabrication or construction permit areas.
Authorization. Only the area supervisor may authorize an employee to enter a tank trailer, dry bulk trailer or truck within the permit area. The area supervisor must determine that the entry permit requirements have been met before authorizing entry.
Appendix E to § 1910.146—Sewer System Entry
Sewer entry differs in three vital respects from other permit entries; first, there rarely exists any way to completely isolate the space (a section of a continuous system) to be entered; second, because isolation is not complete, the atmosphere may suddenly and unpredictably become lethally hazardous (toxic, flammable or explosive) from causes beyond the control of the entrant or employer, and third, experienced sewer workers are especially knowledgeable in entry and work in their permit spaces because of their frequent entries. Unlike other employments where permit space entry is a rare and exceptional event, sewer workers' usual work environment is a permit space.
The employer should designate as entrants only employees who are thoroughly trained in the employer's sewer entry procedures and who demonstrate that they follow these entry procedures exactly as prescribed when performing sewer entries.
Entrants should be trained in the use of, and be equipped with, atmospheric monitoring equipment which sounds an audible alarm, in addition to its visual readout, whenever one of the following conditions are encountered: Oxygen concentration less than 19.5 percent; flammable gas or vapor at 10 percent or more of the lower flammable limit (LFL); or hydrogen sulfide or carbon monoxide at or above 10 ppm or 35 ppm, respectively, measured as an 8-hour time-weighted average. Atmospheric monitoring equipment needs to be calibrated according to the manufacturer's instructions. The oxygen sensor/broad range sensor is best suited for initial use in situations where the actual or potential contaminants have not been identified, because broad range sensors, unlike substance-specific sensors, enable employers to obtain an overall reading of the hydrocarbons (flammables) present in the space. However, such sensors only indicate that a hazardous threshold of a class of chemicals has been exceeded. They do not measure the levels of contamination of specific substances. Therefore, substance-specific devices, which measure the actual levels of specific substances, are best suited for use where actual and potential contaminants have been identified. The measurements obtained with substance-specific devices are of vital importance to the employer when decisions are made concerning the measures necessary to protect entrants (such as ventilation or personal protective equipment) and the setting and attainment of appropriate entry conditions. However, the sewer environment may suddenly and unpredictably change, and the substance-specific devices may not detect the potentially lethal atmospheric hazards which may enter the sewer environment.
Although OSHA considers the information and guidance provided above to be appropriate and useful in most sewer entry situations, the Agency emphasizes that each employer must consider the unique circumstances, including the predictability of the atmosphere, of the sewer permit spaces in the employer's workplace in preparing for entry. Only the employer can decide, based upon his or her knowledge of, and experience with permit spaces in sewer systems, what the best type of testing instrument may be for any specific entry operation.
The selected testing instrument should be carried and used by the entrant in sewer line work to monitor the atmosphere in the entrant's environment, and in advance of the entrant's direction of movement, to warn the entrant of any deterioration in atmospheric conditions. Where several entrants are working together in the same immediate location, one instrument, used by the lead entrant, is acceptable.
Sewer crews should develop and maintain liaison, to the extent possible, with the local weather bureau and fire and emergency services in their area so that sewer work may be delayed or interrupted and entrants withdrawn whenever sewer lines might be suddenly flooded by rain or fire suppression activities, or whenever flammable or other hazardous materials are released into sewers during emergencies by industrial or transportation accidents.
Entry into large bore sewers may require the use of special equipment. Such equipment might include such items as atmosphere monitoring devices with automatic audible alarms, escape self-contained breathing apparatus (ESCBA) with at least 10 minute air supply (or other NIOSH approved self-rescuer), and waterproof flashlights, and may also include boats and rafts, radios and rope stand-offs for pulling around bends and corners as needed.
Appendix F to § 1910.146—Rescue Team or Rescue Service Evaluation Criteria (Non-Mandatory)
A. Initial Evaluation
I. The employer should meet with the prospective rescue service to facilitate the evaluations required by § 1910.146(k)(1)(i) and § 1910.146(k)(1)(ii). At a minimum, if an off-site rescue service is being considered, the employer must contact the service to plan and coordinate the evaluations required by the standard. Merely posting the service's number or planning to rely on the 911 emergency phone number to obtain these services at the time of a permit space emergency would not comply with paragraph (k)(1) of the standard.
II. The capabilities required of a rescue service vary with the type of permit spaces from which rescue may be necessary and the hazards likely to be encountered in those spaces. Answering the questions below will assist employers in determining whether the rescue service is capable of performing rescues in the permit spaces present at the employer's workplace.
1. What are the needs of the employer with regard to response time (time for the rescue service to receive notification, arrive at the scene, and set up and be ready for entry)? For example, if entry is to be made into an IDLH atmosphere, or into a space that can quickly develop an IDLH atmosphere (if ventilation fails or for other reasons), the rescue team or service would need to be standing by at the permit space. On the other hand, if the danger to entrants is restricted to mechanical hazards that would cause injuries (e.g., broken bones, abrasions) a response time of 10 or 15 minutes might be adequate.
2. How quickly can the rescue team or service get from its location to the permit spaces from which rescue may be necessary? Relevant factors to consider would include: the location of the rescue team or service relative to the employer's workplace, the quality of roads and highways to be traveled, potential bottlenecks or traffic congestion that might be encountered in transit, the reliability of the rescuer's vehicles, and the training and skill of its drivers.
3. What is the availability of the rescue service? Is it unavailable at certain times of the day or in certain situations? What is the likelihood that key personnel of the rescue service might be unavailable at times? If the rescue service becomes unavailable while an entry is underway, does it have the capability of notifying the employer so that the employer can instruct the attendant to abort the entry immediately?
4. Does the rescue service meet all the requirements of paragraph (k)(2) of the standard? If not, has it developed a plan that will enable it to meet those requirements in the future? If so, how soon can the plan be implemented?
5. For off-site services, is the service willing to perform rescues at the employer's workplace? (An employer may not rely on a rescuer who declines, for whatever reason, to provide rescue services.)
6. Is an adequate method for communications between the attendant, employer and prospective rescuer available so that a rescue request can be transmitted to the rescuer without delay? How soon after notification can a prospective rescuer dispatch a rescue team to the entry site?
7. For rescues into spaces that may pose significant atmospheric hazards and from which rescue entry, patient packaging and retrieval cannot be safely accomplished in a relatively short time (15-20 minutes), employers should consider using airline respirators (with escape bottles) for the rescuers and to supply rescue air to the patient. If the employer decides to use SCBA, does the prospective rescue service have an ample supply of replacement cylinders and procedures for rescuers to enter and exit (or be retrieved) well within the SCBA's air supply limits?
8. If the space has a vertical entry over 5 feet in depth, can the prospective rescue service properly perform entry rescues? Does the service have the technical knowledge and equipment to perform rope work or elevated rescue, if needed?
9. Does the rescue service have the necessary skills in medical evaluation, patient packaging and emergency response?
10. Does the rescue service have the necessary equipment to perform rescues, or must the equipment be provided by the employer or another source?
B. Performance Evaluation
Rescue services are required by paragraph (k)(2)(iv) of the standard to practice rescues at least once every 12 months, provided that the team or service has not successfully performed a permit space rescue within that time. As part of each practice session, the service should perform a critique of the practice rescue, or have another qualified party perform the critique, so that deficiencies in procedures, equipment, training, or number of personnel can be identified and corrected. The results of the critique, and the corrections made to respond to the deficiencies identified, should be given to the employer to enable it to determine whether the rescue service can quickly be upgraded to meet the employer's rescue needs or whether another service must be selected. The following questions will assist employers and rescue teams and services evaluate their performance.
1. Have all members of the service been trained as permit space entrants, at a minimum, including training in the potential hazards of all permit spaces, or of representative permit spaces, from which rescue may be needed? Can team members recognize the signs, symptoms, and consequences of exposure to any hazardous atmospheres that may be present in those permit spaces?
2. Is every team member provided with, and properly trained in, the use and need for PPE, such as SCBA or fall arrest equipment, which may be required to perform permit space rescues in the facility? Is every team member properly trained to perform his or her functions and make rescues, and to use any rescue equipment, such as ropes and backboards, that may be needed in a rescue attempt?
3. Are team members trained in the first aid and medical skills needed to treat victims overcome or injured by the types of hazards that may be encountered in the permit spaces at the facility?
4. Do all team members perform their functions safely and efficiently? Do rescue service personnel focus on their own safety before considering the safety of the victim?
5. If necessary, can the rescue service properly test the atmosphere to determine if it is IDLH?
6. Can the rescue personnel identify information pertinent to the rescue from entry permits, hot work permits, and MSDSs?
7. Has the rescue service been informed of any hazards to personnel that may arise from outside the space, such as those that may be caused by future work near the space?
8. If necessary, can the rescue service properly package and retrieve victims from a permit space that has a limited size opening (less than 24 inches (60.9 cm) in diameter), limited internal space, or internal obstacles or hazards?
9. If necessary, can the rescue service safely perform an elevated (high angle) rescue?
10. Does the rescue service have a plan for each of the kinds of permit space rescue operations at the facility? Is the plan adequate for all types of rescue operations that may be needed at the facility? Teams may practice in representative spaces, or in spaces that are “worst-case” or most restrictive with respect to internal configuration, elevation, and portal size. The following characteristics of a practice space should be considered when deciding whether a space is truly representative of an actual permit space:
[58 FR 4549, Jan. 14, 1993; 58 FR 34845, 34846, June 29, 1993, as amended at 59 FR 26114, May 19, 1994; 63 FR 66038, 66039, Dec. 1, 1998; 76 FR 80739, Dec. 27, 2011]
Affected employee. An employee whose job requires him/her to operate or use a machine or equipment on which servicing or maintenance is being performed under lockout or tagout, or whose job requires him/her to work in an area in which such servicing or maintenance is being performed.
Authorized employee. A person who locks out or tags out machines or equipment in order to perform servicing or maintenance on that machine or equipment. An affected employee becomes an authorized employee when that employee's duties include performing servicing or maintenance covered under this section.
Capable of being locked out. An energy isolating device is capable of being locked out if it has a hasp or other means of attachment to which, or through which, a lock can be affixed, or it has a locking mechanism built into it. Other energy isolating devices are capable of being locked out, if lockout can be achieved without the need to dismantle, rebuild, or replace the energy isolating device or permanently alter its energy control capability.
Energized. Connected to an energy source or containing residual or stored energy.
Energy isolating device. A mechanical device that physically prevents the transmission or release of energy, including but not limited to the following: A manually operated electrical circuit breaker; a disconnect switch; a manually operated switch by which the conductors of a circuit can be disconnected from all ungrounded supply conductors, and, in addition, no pole can be operated independently; a line valve; a block; and any similar device used to block or isolate energy. Push buttons, selector switches and other control circuit type devices are not energy isolating devices.
Energy source. Any source of electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other energy.
Hot tap. A procedure used in the repair, maintenance and services activities which involves welding on a piece of equipment (pipelines, vessels or tanks) under pressure, in order to install connections or appurtenances. It is commonly used to replace or add sections of pipeline without the interruption of service for air, gas, water, steam, and petrochemical distribution systems.
Lockout. The placement of a lockout device on an energy isolating device, in accordance with an established procedure, ensuring that the energy isolating device and the equipment being controlled cannot be operated until the lockout device is removed.
Lockout device. A device that utilizes a positive means such as a lock, either key or combination type, to hold an energy isolating device in a safe position and prevent the energizing of a machine or equipment. Included are blank flanges and bolted slip blinds.
Normal production operations. The utilization of a machine or equipment to perform its intended production function.
Servicing and/or maintenance. Workplace activities such as constructing, installing, setting up, adjusting, inspecting, modifying, and maintaining and/or servicing machines or equipment. These activities include lubrication, cleaning or unjamming of machines or equipment and making adjustments or tool changes, where the employee may be exposed to the unexpected energization or startup of the equipment or release of hazardous energy.
Setting up. Any work performed to prepare a machine or equipment to perform its normal production operation.
Tagout. The placement of a tagout device on an energy isolating device, in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed.
Tagout device. A prominent warning device, such as a tag and a means of attachment, which can be securely fastened to an energy isolating device in accordance with an established procedure, to indicate that the energy isolating device and the equipment being controlled may not be operated until the tagout device is removed.
The employer shall establish a program consisting of energy control procedures, employee training and periodic inspections to ensure that before any employee performs any servicing or maintenance on a machine or equipment where the unexpected energizing, start up or release of stored energy could occur and cause injury, the machine or equipment shall be isolated from the energy source, and rendered inoperative.
Lockout and tagout devices shall be standardized within the facility in at least one of the following criteria: Color; shape; or size; and additionally, in the case of tagout devices, print and format shall be standardized.
Lockout devices shall be substantial enough to prevent removal without the use of excessive force or unusual techniques, such as with the use of bolt cutters or other metal cutting tools.
Tagout devices, including and their means of attachment, shall be substantial enough to prevent inadvertent or accidental removal. Tagout device attachment means shall be of a non-reusable type, attachable by hand, self-locking, and non-releasable with a minimum unlocking strength of no less than 50 pounds and having the general design and basic characteristics of being at least equivalent to a one-piece, all-environment-tolerant nylon cable tie.
Lockout devices and tagout devices shall indicate the identity of the employee applying the device(s).
Lockout or tagout shall be performed only by the authorized employees who are performing the servicing or maintenance.
Affected employees shall be notified by the employer or authorized employee of the application and removal of lockout devices or tagout devices. Notification shall be given before the controls are applied, and after they are removed from the machine or equipment.
The established procedures for the application of energy control (the lockout or tagout procedures) shall cover the following elements and actions and shall be done in the following sequence:
Before an authorized or affected employee turns off a machine or equipment, the authorized employee shall have knowledge of the type and magnitude of the energy, the hazards of the energy to be controlled, and the method or means to control the energy.
The machine or equipment shall be turned off or shut down using the procedures established for the machine or equipment. An orderly shutdown must be utilized to avoid any additional or increased hazard(s) to employees as a result of the equipment stoppage.
All energy isolating devices that are needed to control the energy to the machine or equipment shall be physically located and operated in such a manner as to isolate the machine or equipment from the energy source(s).
Prior to starting work on machines or equipment that have been locked out or tagged out, the authorized employee shall verify that isolation and deenergization of the machine or equipment have been accomplished.
Before lockout or tagout devices are removed and energy is restored to the machine or equipment, procedures shall be followed and actions taken by the authorized employee(s) to ensure the following:
The work area shall be inspected to ensure that nonessential items have been removed and to ensure that machine or equipment components are operationally intact.
Each lockout or tagout device shall be removed from each energy isolating device by the employee who applied the device. Exception to paragraph (e)(3): When the authorized employee who applied the lockout or tagout device is not available to remove it, that device may be removed under the direction of the employer, provided that specific procedures and training for such removal have been developed, documented and incorporated into the employer's energy control program. The employer shall demonstrate that the specific procedure provides equivalent safety to the removal of the device by the authorized employee who applied it. The specific procedure shall include at least the following elements:
Specific procedures shall be utilized during shift or personnel changes to ensure the continuity of lockout or tagout protection, including provision for the orderly transfer of lockout or tagout device protection between off-going and oncoming employees, to minimize exposure to hazards from the unexpected energization or start-up of the machine or equipment, or the release of stored energy.
Appendix A to § 1910.147—Typical Minimal Lockout Procedure
General
The following simple lockout procedure is provided to assist employers in developing their procedures so they meet the requirements of this standard. When the energy isolating devices are not lockable, tagout may be used, provided the employer complies with the provisions of the standard which require additional training and more rigorous periodic inspections. When tagout is used and the energy isolating devices are lockable, the employer must provide full employee protection ( see paragraph (c)(3)) and additional training and more rigorous periodic inspections are required. For more complex systems, more comprehensive procedures may need to be developed, documented and utilized.
Lockout Procedure
Lockout procedure for
Purpose
This procedure establishes the minimum requirements for the lockout of energy isolating devices whenever maintenance or servicing is done on machines or equipment. It shall be used to ensure that the machine or equipment is stopped, isolated from all potentially hazardous energy sources and locked out before employees perform any servicing or maintenance where the unexpected energization or start-up of the machine or equipment or release of stored energy could cause injury.
Compliance With This Program
All employees are required to comply with the restrictions and limitations imposed upon them during the use of lockout. The authorized employees are required to perform the lockout in accordance with this procedure. All employees, upon observing a machine or piece of equipment which is locked out to perform servicing or maintenance shall not attempt to start, energize or use that machine or equipment.
Type of compliance enforcement to be taken for violation of the above.
Sequence of Lockout
Name(s)/Job Title(s) of affected employees and how to notify.
Type(s) and magnitude(s) of energy, its hazards and the methods to control the energy.
Type(s) and location(s) of machine or equipment operating controls.
Type(s) and location(s) of energy isolating devices.
Type(s) of stored energy—methods to dissipate or restrain.
Caution: Return operating control(s) to neutral or “off” position after verifying the isolation of the equipment.
Method of verifying the isolation of the equipment.
Restoring Equipment to Service. When the servicing or maintenance is completed and the machine or equipment is ready to return to normal operating condition, the following steps shall be taken.
[54 FR 36687, Sept. 1, 1989, as amended at 54 FR 42498, Oct. 17, 1989; 55 FR 38685, 38686, Sept. 20, 1990; 76 FR 24698, May 2, 2011; 76 FR 44265, July 25, 2011]
Appendix A to § 1910.151—First aid kits (Non-Mandatory)
First aid supplies are required to be readily available under paragraph § 1910.151(b). An example of the minimal contents of a generic first aid kit is described in American National Standard (ANSI) Z308.1-1998 “Minimum Requirements for Workplace First-aid Kits.” The contents of the kit listed in the ANSI standard should be adequate for small worksites. When larger operations or multiple operations are being conducted at the same location, employers should determine the need for additional first aid kits at the worksite, additional types of first aid equipment and supplies and additional quantities and types of supplies and equipment in the first aid kits.
In a similar fashion, employers who have unique or changing first-aid needs in their workplace may need to enhance their first-aid kits. The employer can use the OSHA 300 log, OSHA 301 log, or other reports to identify these unique problems. Consultation from the local fire/rescue department, appropriate medical professional, or local emergency room may be helpful to employers in these circumstances. By assessing the specific needs of their workplace, employers can ensure that reasonably anticipated supplies are available. Employers should assess the specific needs of their worksite periodically and augment the first aid kit appropriately.
If it is reasonably anticipated that employees will be exposed to blood or other potentially infectious materials while using first aid supplies, employers are required to provide appropriate personal protective equipment (PPE) in compliance with the provisions of the Occupational Exposure to Blood borne Pathogens standard, § 1910.1030(d)(3) (56 FR 64175). This standard lists appropriate PPE for this type of exposure, such as gloves, gowns, face shields, masks, and eye protection.
[39 FR 23502, June 27, 1974, as amended at 63 FR 33466, June 18, 1998; 70 FR 1141, Jan. 5, 2005; 76 FR 80739, Dec. 27, 2011]
This subpart contains requirements for fire brigades, and all portable and fixed fire suppression equipment, fire detection systems, and fire or employee alarm systems installed to meet the fire protection requirements of 29 CFR part 1910.
This subpart applies to all employments except for maritime, construction, and agriculture.
[45 FR 60704, Sept. 12, 1980, as amended at 53 FR 12122, Apr. 12, 1988]
This section contains requirements for the organization, training, and personal protective equipment of fire brigades whenever they are established by an employer.
The requirements of this section apply to fire brigades, industrial fire departments and private or contractual type fire departments. Personal protective equipment requirements apply only to members of fire brigades performing interior structural fire fighting. The requirements of this section do not apply to airport crash rescue or forest fire fighting operations.
The employer shall prepare and maintain a statement or written policy which establishes the existence of a fire brigade; the basic organizational structure; the type, amount, and frequency of training to be provided to fire brigade members; the expected number of members in the fire brigade; and the functions that the fire brigade is to perform at the workplace. The organizational statement shall be available for inspection by the Assistant Secretary and by employees or their designated representatives.
The employer shall assure that employees who are expected to do interior structural fire fighting are physically capable of performing duties which may be assigned to them during emergencies. The employer shall not permit employees with known heart disease, epilepsy, or emphysema, to participate in fire brigade emergency activities unless a physician's certificate of the employees' fitness to participate in such activities is provided. For employees assigned to fire brigades before September 15, 1980, this paragraph is effective on September 15, 1990. For employees assigned to fire brigades on or after September 15, 1980, this paragraph is effective December 15, 1980.
The employer shall maintain and inspect, at least annually, fire fighting equipment to assure the safe operational condition of the equipment. Portable fire extinguishers and respirators shall be inspected at least monthly. Fire fighting equipment that is in damaged or unserviceable condition shall be removed from service and replaced.
The following requirements apply to those employees who perform interior structural fire fighting. The requirements do not apply to employees who use fire extinguishers or standpipe systems to control or extinguish fires only in the incipient stage.
Such apparatus shall also be worn during emergency situations involving toxic substances.
[45 FR 60706, Sept. 12, 1980; 46 FR 24557, May 1, 1981; 49 FR 18295, Apr. 30, 1984; 61 FR 9239, Mar. 7, 1996; 63 FR 1284, Jan. 8, 1998; 63 FR 33467, June 18, 1998; 73 FR 75584, Dec. 12, 2008]
The requirements of this section apply to the placement, use, maintenance, and testing of portable fire extinguishers provided for the use of employees. Paragraph (d) of this section does not apply to extinguishers provided for employee use on the outside of workplace buildings or structures. Where extinguishers are provided but are not intended for employee use and the employer has an emergency action plan and a fire prevention plan that meet the requirements of 29 CFR 1910.38 and 29 CFR 1910.39 respectively, then only the requirements of paragraphs (e) and (f) of this section apply.
| Type of extinguishers | Test interval (years) |
|---|---|
| Soda acid (soldered brass shells) (until 1/1/82) | ( 1 ) |
| Soda acid (stainless steel shell) | 5 |
| Cartridge operated water and/or antifreeze | 5 |
| Stored pressure water and/or antifreeze | 5 |
| Wetting agent | 5 |
| Foam (soldered brass shells) (until 1/1/82) | ( 1 ) |
| Foam (stainless steel shell) | 5 |
| Aqueous Film Forming foam (AFFF) | 5 |
| Loaded stream | 5 |
| Dry chemical with stainless steel | 5 |
| Carbon dioxide | 5 |
| Dry chemical, stored pressure, with mild steel, brazed brass or aluminum shells | 12 |
| Dry chemical, cartridge or cylinder operated, with mild steel shells | 12 |
| Halon 1211 | 12 |
| Halon 1301 | 12 |
| Dry powder, cartridge or cylinder operated with mild steel shells | 12 |
| 1 Extinguishers having shells constructed of copper or brass joined by soft solder or rivets shall not be hydrostatically tested and shall be removed from service by January 1, 1982. (Not permitted) |
[45 FR 60708, Sept. 12, 1980; 46 FR 24557, May 1, 1981, as amended at 51 FR 34560, Sept. 29, 1986; 61 FR 9239, Mar. 7, 1996; 67 FR 67964, Nov. 7, 2002]
This section applies to all small hose, Class II, and Class III standpipe systems installed to meet the requirements of a particular OSHA standard.
This section does not apply to Class I standpipe systems.
The employer shall assure that standpipes are located or otherwise protected against mechanical damage. Damaged standpipes shall be repaired promptly.
Where reels or cabinets are provided to contain fire hose, the employer shall assure that they are designed to facilitate prompt use of the hose valves, the hose, and other equipment at the time of a fire or other emergency. The employer shall assure that the reels and cabinets are conspicuously identified and used only for fire equipment.
The employer shall assure that standpipe hose is equipped with shut-off type nozzles.
The minimum water supply for standpipe and hose systems, which are provided for the use of employees, shall be sufficient to provide 100 gallons per minute (6.3 l/s) for a period of at least thirty minutes.
[45 FR 60710, Sept. 12, 1980, as amended at 61 FR 9239, Mar. 7, 1996]
Automatic sprinkler systems installed in workplaces, but not required by OSHA, are exempt from the requirements of this section.
The employer shall properly maintain an automatic sprinkler system installed to comply with this section. The employer shall assure that a main drain flow test is performed on each system annually. The inspector's test valve shall be opened at least every two years to assure that the sprinkler system operates properly.
The employer shall conduct proper acceptance tests on sprinkler systems installed for employee protection after January 1, 1981, and record the dates of such tests. Proper acceptance tests include the following:
The employer shall assure that every automatic sprinkler system is provided with at least one automatic water supply capable of providing design water flow for at least 30 minutes. An auxiliary water supply or equivalent protection shall be provided when the automatic water supply is out of service, except for systems of 20 or fewer sprinklers.
The employer may attach hose connections for fire fighting use to wet pipe sprinkler systems provided that the water supply satisfies the combined design demand for sprinklers and standpipes.
The employer shall assure that automatic sprinkler system piping is protected against freezing and exterior surface corrosion.
The employer shall assure that all dry sprinkler pipes and fittings are installed so that the system may be totally drained.
On all sprinkler systems having more than twenty (20) sprinklers, the employer shall assure that a local waterflow alarm is provided which sounds an audible signal on the premises upon water flow through the system equal to the flow from a single sprinkler.
The employer shall assure that sprinklers are spaced to provide a maximum protection area per sprinkler, a minimum of interference to the discharge pattern by building or structural members or building contents and suitable sensitivity to possible fire hazards. The minimum vertical clearance between sprinklers and material below shall be 18 inches (45.7 cm).
The employer shall assure that hydraulically designed automatic sprinkler systems or portions thereof are identified and that the location, number of sprinklers in the hydraulically designed section, and the basis of the design is indicated. Central records may be used in lieu of signs at sprinkler valves provided the records are available for inspection and copying by the Assistant Secretary.
[45 FR 60710, Sept. 12, 1980; 46 FR 24557, May 1, 1981]
[45 FR 60711, Sept. 12, 1980]
This section applies to all fixed extinguishing systems, using dry chemical as the extinguishing agent, installed to meet a particular OSHA standard. These systems shall also comply with § 1910.160.
[45 FR 60712, Sept. 12, 1980]
This section applies to all fixed extinguishing systems, using a gas as the extinguishing agent, installed to meet a particular OSHA standard. These systems shall also comply with § 1910.160. In some cases, the gas may be in a liquid state during storage.
The requirements of paragraphs (b)(2) and (b)(4) through (b)(6) shall apply only to total flooding systems.
[45 FR 60712, Sept. 12, 1980; 46 FR 24557, May 1, 1981]
This section applies to all fixed extinguishing systems, using water or foam solution as the extinguishing agent, installed to meet a particular OSHA standard. These systems shall also comply with § 1910.160. This section does not apply to automatic sprinkler systems which are covered under § 1910.159.
[45 FR 60712, Sept. 12, 1980]
This section applies to all automatic fire detection systems installed to meet the requirements of a particular OSHA standard.
[45 FR 60713, Sept. 12, 1980]
The employer shall assure that manually operated actuation devices for use in conjunction with employee alarms are unobstructed, conspicuous and readily accessible.
[45 FR 60713, Sept. 12, 1980]
§ 1910.156 Fire brigades.
1. Scope. This section does not require an employer to organize a fire brigade. However, if an employer does decide to organize a fire brigade, the requirements of this section apply.
2. Pre-fire planning. It is suggested that pre-fire planning be conducted by the local fire department and/or the workplace fire brigade in order for them to be familiar with the workplace and process hazards. Involvement with the local fire department or fire prevention bureau is encouraged to facilitate coordination and cooperation between members of the fire brigade and those who might be called upon for assistance during a fire emergency.
3. Organizational statement. In addition to the information required in the organizational statement, paragraph 1910.156(b)(1), it is suggested that the organizational statement also contain the following information: a description of the duties that the fire brigade members are expected to perform; the line authority of each fire brigade officer; the number of the fire brigade officers and number of training instructors; and a list and description of the types of awards or recognition that brigade members may be eligible to receive.
4. Physical capability. The physical capability requirement applies only to those fire brigade members who perform interior structural fire fighting. Employees who cannot meet the physical capability requirement may still be members of the fire brigade as long as such employees do not perform interior structural fire fighting. It is suggested that fire brigade members who are unable to perform interior structural fire fighting be assigned less stressful and physically demanding fire brigade duties, e.g., certain types of training, recordkeeping, fire prevention inspection and maintenance, and fire pump operations.
Physically capable can be defined as being able to perform those duties specified in the training requirements of section 1910.156(c). Physically capable can also be determined by physical performance tests or by a physical examination when the examining physician is aware of the duties that the fire brigade member is expected to perform.
It is also recommended that fire brigade members participate in a physical fitness program. There are many benefits which can be attributed to being physically fit. It is believed that physical fitness may help to reduce the number of sprain and strain injuries as well as contributing to the improvement of the cardiovascular system.
5. Training and education. The paragraph on training and education does not contain specific training and education requirements because the type, amount, and frequency of training and education will be as varied as are the purposes for which fire brigades are organized. However, the paragraph does require that training and education be commensurate with those functions that the fire brigade is expected to perform; i.e., those functions specified in the organizational statement. Such a performance requirement provides the necessary flexibility to design a training program which meets the needs of individual fire brigades.
At a minimum, hands-on training is required to be conducted annually for all fire brigade members. However, for those fire brigade members who are expected to perform interior structural fire fighting, some type of training or education session must be provided at least quarterly.
In addition to the required hands-on training, it is strongly recommended that fire brigade members receive other types of training and education such as: classroom instruction, review of emergency action procedures, pre-fire planning, review of special hazards in the workplace, and practice in the use of self-contained breathing apparatus.
It is not necessary for the employer to duplicate the same training or education that a fire brigade member receives as a member of a community volunteer fire department, rescue squad, or similar organization. However, such training or education must have been provided to the fire brigade member within the past year and it must be documented that the fire brigade member has received the training or education. For example: there is no need for a fire brigade member to receive another training class in the use of positive-pressure self-contained breathing apparatus if the fire brigade member has recently completed such training as a member of a community fire department. Instead, the fire brigade member should receive training or education covering other important equipment or duties of the fire brigade as they relate to the workplace hazards, facilities and processes.
It is generally recognized that the effectiveness of fire brigade training and education depends upon the expertise of those providing the training and education as well as the motivation of the fire brigade members. Fire brigade training instructors must receive a higher level of training and education than the fire brigade members they will be teaching. This includes being more knowledgeable about the functions to be performed by the fire brigade and the hazards involved. The instructors should be qualified to train fire brigade members and demonstrate skills in communication, methods of teaching, and motivation. It is important for instructors and fire brigade members alike to be motivated toward the goals of the fire brigade and be aware of the importance of the service that they are providing for the protection of other employees and the workplace.
It is suggested that publications from the International Fire Service Training Association, the National Fire Protection Association (NFPA-1041), the International Society of Fire Service Instructors and other fire training sources be consulted for recommended qualifications of fire brigade training instructors.
In order to be effective, fire brigades must have competent leadership and supervision. It is important for those who supervise the fire brigade during emergency situations, e.g., fire brigade chiefs, leaders, etc., to receive the necessary training and education for supervising fire brigade activities during these hazardous and stressful situations. These fire brigade members with leadership responsibilities should demonstrate skills in strategy and tactics, fire suppression and prevention techniques, leadership principles, pre-fire planning, and safety practices. It is again suggested that fire service training sources be consulted for determining the kinds of training and education which are necessary for those with fire brigade leadership responsibilities.
It is further suggested that fire brigade leaders and fire brigade instructors receive more formalized training and education on a continuing basis by attending classes provided by such training sources as universities and university fire extension services.
The following recommendations should not be considered to be all of the necessary elements of a complete comprehensive training program, but the information may be helpful as a guide in developing a fire brigade training program.
All fire brigade members should be familiar with exit facilities and their location, emergency escape routes for handicapped workers, and the workplace “emergency action plan.”
In addition, fire brigade members who are expected to control and extinguish fires in the incipient stage should, at a minimum, be trained in the use of fire extinguishers, standpipes, and other fire equipment they are assigned to use. They should also be aware of first aid medical procedures and procedures for dealing with special hazards to which they may be exposed. Training and education should include both classroom instruction and actual operation of the equipment under simulated emergency conditions. Hands-on type training must be conducted at least annually but some functions should be reviewed more often.
In addition to the above training, fire brigade members who are expected to perform emergency rescue and interior structural fire fighting should, at a minimum, be familiar with the proper techniques in rescue and fire suppression procedures. Training and education should include fire protection courses, classroom training, simulated fire situations including “wet drills” and, when feasible, extinguishment of actual mock fires. Frequency of training or education must be at least quarterly, but some drills or classroom training should be conducted as often as monthly or even weekly to maintain the proficiency of fire brigade members.
There are many excellent sources of training and education that the employer may want to use in developing a training program for the workplace fire brigade. These sources include publications, seminars, and courses offered by universities.
There are also excellent fire school courses by such facilities as Texas A and M University, Delaware State Fire School, Lamar University, and Reno Fire School, that deal with those unique hazards which may be encountered by fire brigades in the oil and chemical industry. These schools, and others, also offer excellent training courses which would be beneficial to fire brigades in other types of industries. These courses should be a continuing part of the training program, and employers are strongly encouraged to take advantage of these excellent resources.
It is also important that fire brigade members be informed about special hazards to which they may be exposed during fire and other emergencies. Such hazards as storage and use areas of flammable liquids and gases, toxic chemicals, water-reactive substances, etc., can pose difficult problems. There must be written procedures developed that describe the actions to be taken in situations involving special hazards. Fire brigade members must be trained in handling these special hazards as well as keeping abreast of any changes that occur in relation to these special hazards.
6. Fire fighting equipment. It is important that fire fighting equipment that is in damaged or unserviceable condition be removed from service and replaced. This will prevent fire brigade members from using unsafe equipment by mistake.
Fire fighting equipment, except portable fire extinguishers and respirators, must be inspected at least annually. Portable fire extinguishers and respirators are required to be inspected at least monthly.
7. Protective clothing.
Paragraph (e) of § 1910.156 does not require all fire brigade members to wear protective clothing. It is not the intention of these standards to require employers to provide a full ensemble of protective clothing for every fire brigade member without consideration given to the types of hazardous environments to which the fire brigade member might be exposed. It is the intention of these standards to require adequate protection for those fire brigade members who might be exposed to fires in an advanced stage, smoke, toxic gases, and high temperatures. Therefore, the protective clothing requirements only apply to those fire brigade members who perform interior structural fire fighting operations.
Additionally, the protective clothing requirements do not apply to the protective clothing worn during outside fire fighting operations (brush and forest fires, crash crew operations) or other special fire fighting activities. It is important that the protective clothing to be worn during these types of fire fighting operations reflect the hazards which are expected to be encountered by fire brigade members.
Section 1910.156 permits an option to achieve foot and leg protection.
The section recognizes the interdependence of protective clothing to cover one or more parts of the body. Therefore, an option is given so that fire brigade members may meet the foot and leg requirements by either wearing long fire-resistive coats in combination with fully extended boots, or by wearing shorter fire-resistive costs in combination with protective trousers and protective shoes or shorter boots.
Paragraph (e)(3) of § 1910.156 provides an option for fire brigade members to achieve body protection. Fire brigade members may wear a fire-resistive coat in combination with fully extended boots, or they may wear a fire-resistive coat in combination with protective trousers.
Fire-resistive coats and protective trousers meeting all of the requirements contained in NFPA 1971-1975 “Protective Clothing for Structural Fire Fighters,” are acceptable as meeting the requirements of this standard.
The lining is required to be permanently attached to the outer shell. However, it is permissible to attach the lining to the outer shell material by stitching in one area such as at the neck. Fastener tape or snap fasteners may be used to secure the rest of the lining to the outer shell to facilitate cleaning. Reference to permanent lining does not refer to a winter liner which is a detachable extra lining used to give added protection to the wearer against the effects of cold weather and wind.
The requirements of the paragraph on hand protection may be met by protective gloves or a glove system. A glove system consists of a combination of different gloves. The usual components of a glove system consist of a pair of gloves, which provide thermal insulation to the hands, worn in combination with a second pair of gloves which provide protection against flame, cut, and puncture.
It is suggested that protective gloves provide dexterity and a sense of feel for objects. Criteria and test methods for dexterity are contained in the NIOSH publications, “The Development of Criteria for Firefighters' Gloves; Vol. I: Glove Requirements” and “Vol. II: Glove Criteria and Test Methods.” These NIOSH publications also contain a permissible modified version of Federal Test Method 191, Method 5903, (paragraph (3) of appendix E) for flame resistance when gloves, rather than glove material, are tested for flame resistance.
Head protective devices are required to be provided with ear flaps so that the ear flaps will be available if needed. It is recommended that ear protection always be used while fighting interior structural fires.
Many head protective devices are equipped with face shields to protect the eyes and face. These face shields are permissible as meeting the eye and face protection requirements of this paragraph as long as such face shields meet the requirements of § 1910.133 of the General Industry Standards.
Additionally, full facepieces, helmets or hoods of approved breathing apparatus which meet the requirements of § 1910.134 and paragraph (f) of § 1910.156 are also acceptable as meeting the eye and face protection requirements.
It is recommended that a flame resistant protective head covering such as a hood or snood, which will not adversely affect the seal of a respirator facepiece, be worn during interior structural fire fighting operations to protect the sides of the face and hair.
8. Respiratory protective devices. Respiratory protection is required to be worn by fire brigade members while working inside buildings or confined spaces where toxic products of combustion or an oxygen deficiency is likely to be present; respirators are also to be worn during emergency situations involving toxic substances. When fire brigade members respond to emergency situations, they may be exposed to unknown contaminants in unknown concentrations. Therefore, it is imperative that fire brigade members wear proper respiratory protective devices during these situations. Additionally, there are many instances where toxic products of combustion are still present during mop-up and overhaul operations. Therefore, fire brigade members should continue to wear respirators during these types of operations.
Self-contained breathing apparatus are not required to be equipped with either a buddy-breathing device or a quick-disconnect valve. However, these accessories may be very useful and are acceptable as long as such accessories do not cause damage to the apparatus, restrict the air flow of the apparatus, or obstruct the normal operation of the apparatus.
Buddy-breathing devices are useful for emergency situations where a victim or another fire brigade member can share the same air supply with the wearer of the apparatus for emergency escape purposes.
The employer is encouraged to provide fire brigade members with an alternative means of respiratory protection to be used only for emergency escape purposes if the self-contained breathing apparatus becomes inoperative. Such alternative means of respiratory protection may be either a buddy-breathing device or an escape self-contained breathing apparatus (ESCBA). The ESCBA is a short-duration respiratory protective device which is approved for only emergency escape purposes. It is suggested that if ESCBA units are used, that they be of at least 5 minutes service life.
Quick-disconnect valves are devices which start the flow of air by insertion of the hose (which leads to the facepiece) into the regulator of self-contained breathing apparatus, and stop the flow of air by disconnecting the hose from the regulator. These devices are particularly useful for those positive-pressure self-contained breathing apparatus which do not have the capability of being switched from the demand to the positive-pressure mode.
The use of a self-contained breathing apparatus where the apparatus can be switched from a demand to a positive-pressure mode is acceptable as long as the apparatus is in the positive-pressure mode when performing interior structural fire fighting operations. Also acceptable are approved respiratory protective devices which have been converted to the positive-pressure type when such modification is accomplished by trained and experienced persons using kits or parts approved by NIOSH and provided by the manufacturer and by following the manufacturer's instructions.
There are situations which require the use of respirators which have a duration of 2 hours or more. Presently, there are no approved positive-pressure apparatus with a rated service life of more than 2 hours. Consequently, negative-pressure self-contained breathing apparatus with a rated service life of more than 2 hours and which have a minimum protection factor of 5,000 as determined by an acceptable quantitative fit test performed on each individual, will be acceptable for use during situations which require long duration apparatus. Long duration apparatus may be needed in such instances as working in tunnels, subway systems, etc. Such negative-pressure breathing apparatus will continue to be acceptable for a maximum of 18 months after a positive-pressure apparatus with the same or longer rated service life of more than 2 hours is certified by NIOSH/MSHA. After this 18 month phase-in period, all self-contained breathing apparatus used for these long duration situations will have to be of the positive-pressure type.
Protection factor (sometimes called fit factor) is defined as the ratio of the contaminant concentrations outside of the respirator to the contaminant concentrations inside the facepiece of the respirator.
Protection factors are determined by quantitative fit tests. An acceptable quantitative fit test should include the following elements:
1. A fire brigade member who is physically and medically capable of wearing respirators, and who is trained in the use of respirators, dons a self-contained breathing apparatus equipped with a device that will monitor the concentration of a contaminant inside the facepiece.
2. The fire brigade member then performs a qualitative fit test to assure the best face to facepiece seal as possible. A qualitative fit test can consist of a negative-pressure test, positive-pressure test, isoamyl acetate vapor (banana oil) test, or an irritant smoke test. For more details on respirator fitting see the NIOSH booklet entitled “A Guide to Industrial Respiratory Protection” June, 1976, and HEW publication No. (NIOSH) 76-189.
3. The wearer should then perform physical activity which reflects the level of work activity which would be expected during fire fighting activities. The physical activity should include simulated fire-ground work activity or physical exercise such as running-in-place, a step test, etc.
4. Without readjusting the apparatus, the wearer is placed in a test atmosphere containing a non-toxic contaminant with a known, constant, concentration.
The protection factor is then determined by dividing the known concentration of the contaminant in the test atmosphere by the concentration of the contaminant inside the facepiece when the following exercises are performed:
The protection factor which is determined must be at least 5,000. The quantitative fit test should be conducted at least three times. It is acceptable to conduct all three tests on the same day. However, there should be at least one hour between tests to reflect the protection afforded by the apparatus during different times of the day.
The above elements are not meant to be a comprehensive, technical description of a quantitative fit test protocol. However, quantitative fit test procedures which include these elements are acceptable for determining protection factors. Procedures for a quantitative fit test are required to be available for inspection by the Assistant Secretary or authorized representative.
Organizations such as Los Alamos Scientific Laboratory, Lawrence Livermore Laboratory, NIOSH, and American National Standards Institute (ANSI) are excellent sources for additional information concerning qualitative and quantitative fit testing.
§ 1910.157 Portable fire extinguishers.
1. Scope and application. The scope and application of this section is written to apply to three basic types of workplaces. First, there are those workplaces where the employer has chosen to evacuate all employees from the workplace at the time of a fire emergency. Second, there are those workplaces where the employer has chosen to permit certain employees to fight fires and to evacuate all other non-essential employees at the time of a fire emergency. Third, there are those workplaces where the employer has chosen to permit all employees in the workplace to use portable fire extinguishers to fight fires.
The section also addresses two kinds of work areas. The entire workplace can be divided into outside (exterior) work areas and inside (interior) work areas. This division of the workplace into two areas is done in recognition of the different types of hazards employees may be exposed to during fire fighting operations. Fires in interior workplaces, pose a greater hazard to employees; they can produce greater exposure to quantities of smoke, toxic gases, and heat because of the capability of a building or structure to contain or entrap these products of combustion until the building can be ventilated. Exterior work areas, normally open to the environment, are somewhat less hazardous, because the products of combustion are generally carried away by the thermal column of the fire. Employees also have a greater selection of evacuation routes if it is necessary to abandon fire fighting efforts.
In recognition of the degree of hazard present in the two types of work areas, the standards for exterior work areas are somewhat less restrictive in regards to extinguisher distribution. Paragraph (a) explains this by specifying which paragraphs in the section apply.
2. Portable fire extinguisher exemptions. In recognition of the three options given to employers in regard to the amount of employee evacuation to be carried out, the standards permit certain exemptions based on the number of employees expected to use fire extinguishers.
Where the employer has chosen to totally evacuate the workplace at the time of a fire emergency and when fire extinguishers are not provided, the requirements of this section do not apply to that workplace.
Where the employer has chosen to partially evacuate the workplace or the effected area at the time of a fire emergency and has permitted certain designated employees to remain behind to operate critical plant operations or to fight fires with extinguishers, then the employer is exempt from the distribution requirements of this section. Employees who will be remaining behind to perform incipient fire fighting or members of a fire brigade must be trained in their duties. The training must result in the employees becoming familiar with the locations of fire extinguishers. Therefore, the employer must locate the extinguishers in convenient locations where the employees know they can be found. For example, they could be mounted in the fire truck or cart that the fire brigade uses when it responds to a fire emergency. They can also be distributed as set forth in the National Fire Protection Association's Standard No. 10, “Portable Fire Extinguishers.”
Where the employer has decided to permit all employees in the workforce to use fire extinguishers, then the entire OSHA section applies.
3. Portable fire extinguisher mounting. Previous standards for mounting fire extinguishers have been criticized for requiring specific mounting locations. In recognition of this criticism, the standard has been rewritten to permit as much flexibility in extinguisher mounting as is acceptable to assure that fire extinguishers are available when needed and that employees are not subjected to injury hazards when they try to obtain an extinguisher.
It is the intent of OSHA to permit the mounting of extinguishers in any location that is accessible to employees without the use of portable devices such as a ladder. This limitation is necessary because portable devices can be moved or taken from the place where they are needed and, therefore, might not be available at the time of an emergency.
Employers are given as much flexibility as possible to assure that employees can obtain extinguishers as fast as possible. For example, an acceptable method of mounting extinguishers in areas where fork lift trucks or tow-motors are used is to mount the units on retractable boards which, by means of counterweighting, can be raised above the level where they could be struck by vehicular traffic. When needed, they can be lowered quickly for use. This method of mounting can also reduce vandalism and unauthorized use of extinguishers. The extinguishers may also be mounted as outlined in the National Fire Protection Association's Standard No. 10, “Portable Fire Extinguishers.”
4. Selection and distribution. The employer is responsible for the proper selection and distribution of fire extinguishers and the determination of the necessary degree of protection. The selection and distribution of fire extinguishers must reflect the type and class of fire hazards associated with a particular workplace.
Extinguishers for protecting Class A hazards may be selected from the following types: water, foam, loaded stream, or multipurpose dry chemical. Extinguishers for protecting Class B hazards may be selected from the following types: Halon 1301, Halon 1211, carbon dioxide, dry chemicals, foam, or loaded stream. Extinguishers for Class C hazards may be selected from the following types: Halon 1301, Halon 1211, carbon dioxide, or dry chemical.
Combustible metal (Class D hazards) fires pose a different type of fire problem in the workplace. Extinguishers using water, gas, or certain dry chemicals cannot extinguish or control this type of fire. Therefore, certain metals have specific dry powder extinguishing agents which can extinguish or control this type of fire. Those agents which have been specifically approved for use on certain metal fires provide the best protection; however, there are also some “universal” type agents which can be used effectively on a variety of combustible metal fires if necessary. The “universal” type agents include: Foundry flux, Lith-X powder, TMB liquid, pyromet powder, TEC powder, dry talc, dry graphite powder, dry sand, dry sodium chloride, dry soda ash, lithium chloride, zirconium silicate, and dry dolomite.
Water is not generally accepted as an effective extinguishing agent for metal fires. When applied to hot burning metal, water will break down into its basic atoms of oxygen and hydrogen. This chemical breakdown contributes to the combustion of the metal. However, water is also a good universal coolant and can be used on some combustible metals, but only under proper conditions and application, to reduce the temperature of the burning metal below the ignition point. For example, automatic deluge systems in magnesium plants can discharge such large quantities of water on burning magnesium that the fire will be extinguished. The National Fire Protection Association has specific standards for this type of automatic sprinkler system. Further information on the control of metal fires with water can be found in the National Fire Protection Association's Fire Protection Handbook.
An excellent source of selection and distribution criteria is found in the National Fire Protection Association's Standard No. 10. Other sources of information include the National Safety Council and the employer's fire insurance carrier.
5. Substitution of standpipe systems for portable fire extinguishers. The employer is permitted to substitute acceptable standpipe systems for portable fire extinguishers under certain circumstances. It is necessary to assure that any substitution will provide the same coverage that portable units provide. This means that fire hoses, because of their limited portability, must be spaced throughout the protected area so that they can reach around obstructions such as columns, machinery, etc. and so that they can reach into closets and other enclosed areas.
6. Inspection, maintenance and testing. The ultimate responsibility for the inspection, maintenance and testing of portable fire extinguishers lies with the employer. The actual inspection, maintenance, and testing may, however, be conducted by outside contractors with whom the employer has arranged to do the work. When contracting for such work, the employer should assure that the contractor is capable of performing the work that is needed to comply with this standard.
If the employer should elect to perform the inspection, maintenance, and testing requirements of this section in-house, then the employer must make sure that those persons doing the work have been trained to do the work and to recognize problem areas which could cause an extinguisher to be inoperable. The National Fire Protection Association provides excellent guidelines in its standard for portable fire extinguishers. The employer may also check with the manufacturer of the unit that has been purchased and obtain guidelines on inspection, maintenance, and testing. Hydrostatic testing is a process that should be left to contractors or individuals using suitable facilities and having the training necessary to perform the work.
Anytime the employer has removed an extinguisher from service to be checked or repaired, alternate equivalent protection must be provided. Alternate equivalent protection could include replacing the extinguisher with one or more units having equivalent or equal ratings, posting a fire watch, restricting the unprotected area from employee exposure, or providing a hose system ready to operate.
7. Hydrostatic testing. As stated before, the employer may contract for hydrostatic testing. However, if the employer wishes to provide the testing service, certain equipment and facilities must be available. Employees should be made aware of the hazards associated with hydrostatic testing and the importance of using proper guards and water pressures. Severe injury can result if extinguisher shells fail violently under hydrostatic pressure.
Employers are encouraged to use contractors who can perform adequate and reliable service. Firms which have been certified by the Materials Transportation Board (MTB) of the U.S. Department of Transportation (DOT) or State licensed extinguisher servicing firms or recognized by the National Association of Fire Equipment Distributors in Chicago, Illinois, are generally acceptable for performing this service.
8. Training and education. This part of the standard is of the utmost importance to employers and employees if the risk of injury or death due to extinguisher use is to be reduced. If an employer is going to permit an employee to fight a workplace fire of any size, the employer must make sure that the employee knows everything necessary to assure the employee's safety.
Training and education can be obtained through many channels. Often, local fire departments in larger cities have fire prevention bureaus or similar organizations which can provide basic fire prevention training programs. Fire insurance companies will have data and information available. The National Fire Protection Association and the National Safety Council will provide, at a small cost, publications that can be used in a fire prevention program.
Actual fire fighting training can be obtained from various sources in the country. The Texas A & M University, the University of Maryland's Fire and Rescue Institute, West Virginia University's Fire Service Extension, Iowa State University's Fire Service Extension and other State training schools and land grant colleges have fire fighting programs directed to industrial applications. Some manufacturers of extinguishers, such as the Ansul Company and Safety First, conduct fire schools for customers in the proper use of extinguishers. Several large corporations have taken time to develop their own on-site training programs which expose employees to the actual “feeling” of fire fighting. Simulated fires for training of employees in the proper use of extinguishers are also an acceptable part of a training program.
In meeting the requirements of this section, the employer may also provide educational materials, without classroom instruction, through the use of employee notice campaigns using instruction sheets or flyers or similar types of informal programs. The employer must make sure that employees are trained and educated to recognize not only what type of fire is being fought and how to fight it, but also when it is time to get away from it and leave fire suppression to more experienced fire fighters.
§ 1910.158 Standpipe and hose systems.
1. Scope and application. This section has been written to provide adequate coverage of those standpipe and hose systems that an employer may install in the workplace to meet the requirements of a particular OSHA standard. For example, OSHA permits the substitution of hose systems for portable fire extinguishers in § 1910.157. If an employer chooses to provide hose systems instead of portable Class A fire extinguishers, then those hose systems used for substitution would have to meet the applicable requirements of § 1910.157. All other standpipe and hose systems not used as a substitute would be exempt from these requirements.
The section specifically exempts Class I large hose systems. By large hose systems, OSHA means those 2 1/2 ″ (6.3 cm) hose lines that are usually associated with fire departments of the size that provide their own water supply through fire apparatus. When the fire gets to the size that outside protection of that degree is necessary, OSHA believes that in most industries employees will have been evacuated from the fire area and the “professional” fire fighters will take control.
2. Protection of standpipes. Employers must make sure that standpipes are protected so that they can be relied upon during a fire emergency. This means protecting the pipes from mechanical and physical damage. There are various means for protecting the equipment such as, but not limited to, enclosing the supply piping in the construction of the building, locating the standpipe in an area which is inaccessible to vehicles, or locating the standpipe in a stairwell.
3. Hose covers and cabinets. The employer should keep fire protection hose equipment in cabinets or inside protective covers which will protect it from the weather elements, dirt or other damaging sources. The use of protective covers must be easily removed or opened to assure that hose and nozzle are accessible. When the employer places hose in a cabinet, the employer must make sure that the hose and nozzle are accessible to employees without subjecting them to injury. In order to make sure that the equipment is readily accessible, the employer must also make sure that the cabinets used to store equipment are kept free of obstructions and other equipment which may interfere with the fast distribution of the fire hose stored in the cabinet.
4. Hose outlets and connections. The employer must assure that employees who use standpipe and hose systems can reach the hose rack and hose valve without the use of portable equipment such as ladders. Hose reels are encouraged for use because one employee can retrieve the hose, charge it, and place it into service without much difficulty.
5. Hose. When the employer elects to provide small hose in lieu of portable fire extinguishers, those hose stations being used for the substitution must have hose attached and ready for service. However, if more than the necessary amount of small hose outlets are provided, hose does not have to be attached to those outlets that would provide redundant coverage. Further, where the installation of hose on outlets may expose the hose to extremely cold climates, the employer may store the hose in houses or similar protective areas and connect it to the outlet when needed.
There is approved lined hose available that can be used to replace unlined hose which is stored on racks in cabinets. The lined hose is constructed so that it can be folded and placed in cabinets in the same manner as unlined hose.
Hose is considered to be unserviceable when it deteriorates to the extent that it can no longer carry water at the required pressure and flow rates. Dry rotted linen or hemp hose, cross threaded couplings, and punctured hose are examples of unserviceable hose.
6. Nozzles. Variable stream nozzles can provide useful variations in water flow and spray patterns during fire fighting operations and they are recommended for employee use. It is recommended that 100 psi (700kPa) nozzle pressure be used to provide good flow patterns for variable stream nozzles. The most desirable attribute for nozzles is the ability of the nozzle person to shut off the water flow at the nozzle when it is necessary. This can be accomplished in many ways. For example, a shut-off nozzle with a lever or rotation of the nozzle to stop flow would be effective, but in other cases a simple globe valve placed between a straight stream nozzle and the hose could serve the same purpose. For straight stream nozzles 50 psi nozzle pressure is recommended. The intent of this standard is to protect the employee from “run-away” hoses if it becomes necessary to drop a pressurized hose line and retreat from the fire front and other related hazards.
7. Design and installation. Standpipe and hose systems designed and installed in accordance with NFPA Standard No. 14, “Standpipe and Hose Systems,” are considered to be in compliance with this standard.
§ 1910.159 Automatic sprinkler systems.
1. Scope and application. This section contains the minimum requirements for design, installation and maintenance of sprinkler systems that are needed for employee safety. The Occupational Safety and Health Administration is aware of the fact that the National Board of Fire Underwriters is no longer an active organization, however, sprinkler systems still exist that were designed and installed in accordance with that organization's standards. Therefore, OSHA will recognize sprinkler systems designed to, and maintained in accordance with, NBFU and earlier NFPA standards.
2. Exemptions. In an effort to assure that employers will continue to use automatic sprinkler systems as the primary fire protection system in workplaces, OSHA is exempting from coverage those systems not required by a particular OSHA standard and which have been installed in workplaces solely for the purpose of protecting property. Many of these types of systems are installed in areas or buildings with little or no employee exposure. An example is those warehouses where employees may enter occasionally to take inventory or move stock. Some employers may choose to shut down those systems which are not specifically required by OSHA rather than upgrade them to comply with the standards. OSHA does not intend to regulate such systems. OSHA only intends to regulate those systems which are installed to comply with a particular OSHA standard.
3. Design. There are two basic types of sprinkler system design. Pipe schedule designed systems are based on pipe schedule tables developed to protect hazards with standard sized pipe, number of sprinklers, and pipe lengths. Hydraulic designed systems are based on an engineered design of pipe size which will produce a given water density or flow rate at any particular point in the system. Either design can be used to comply with this standard.
The National Fire Protection Association's Standard No. 13, “Automatic Sprinkler Systems,” contains the tables needed to design and install either type of system. Minimum water supplies, densities, and pipe sizes are given for all types of occupancies.
The employer may check with a reputable fire protection engineering consultant or sprinkler design company when evaluating existing systems or designing a new installation.
With the advent of new construction materials for the manufacuture of sprinkler pipe, materials, other than steel have been approved for use as sprinkler pipe. Selection of pipe material should be made on the basis of the type of installation and the acceptability of the material to local fire and building officials where such systems may serve more than one purpose.
Before new sprinkler systems are placed into service, an acceptance test is to be conducted. The employer should invite the installer, designer, insurance representative, and a local fire official to witness the test. Problems found during the test are to be corrected before the system is placed into service.
4. Maintenance. It is important that any sprinkler system maintenance be done only when there is minimal employee exposure to the fire hazard. For example, if repairs or changes to the system are to be made, they should be made during those hours when employees are not working or are not occupying that portion of the workplace protected by the portion of the system which has been shut down.
The procedures for performing a flow test via a main drain test or by the use of an inspector's test valve can be obtained from the employer's fire insurance company or from the National Fire Protection Association's Standard No. 13A, “Sprinkler System, Maintenance.”
5. Water supplies. The water supply to a sprinkler system is one of the most important factors an employer should consider when evaluationg a system. Obviously, if there is no water supply, the system is useless. Water supplies can be lost for various reasons such as improperly closed valves, excessive demand, broken water mains, and broken fire pumps. The employer must be able to determine if or when this type of condition exists either by performing a main drain test or visual inspection. Another problem may be an inadequate water supply. For example, a light hazard occupancy may, through rehabilitation or change in tenants, become an ordinary or high hazard occupancy. In such cases, the existing water supply may not be able to provide the pressure or duration necessary for proper protection. Employers must assure that proper design and tests have been made to assure an adequate water supply. These tests can be arranged through the employer's fire insurance carrier or through a local sprinkler maintenance company or through the local fire prevention organization.
Anytime the employer must shut down the primary water supply for a sprinkler system, the standard requires that equivalent protection be provided. Equivalent protection may include a fire watch with extinguishers or hose lines in place and manned, or a secondary water supply such as a tank truck and pump, or a tank or fire pond with fire pumps, to protect the areas where the primary water supply is limited or shut down. The employer may also require evacuation of the workplace and have an emergency action plan which specifies such action.
6. Protection of piping. Piping which is exposed to corrosive atmospheres, either chemical or natural, can become defective to the extent that it is useless. Employers must assure that piping is protected from corrosion by its material of construction, e.g., stainless steel, or by a protective coating, e.g., paint.
7. Sprinklers. When an employer finds it necessary to replace sprinkler system components or otherwise change a sprinkler's design, employer should make a complete fire protection engineering survey of that part of the system being changed. This review should assure that the changes to the system will not alter the effectiveness of the system as it is presently designed. Water supplies, densities and flow characteristics should be maintained.
8. Protection of sprinklers. All components of the system must be protected from mechanical impact damage. This can be achieved with the use of mechanical guards or screens or by locating components in areas where physical contact is impossible or limited.
9. Sprinkler alarms. The most recognized sprinkler alarm is the water motor gong or bell that sounds when water begins to flow through the system. This is not however, the only type of acceptable water flow alarm. Any alarm that gives an indication that water is flowing through the system is acceptable. For example, a siren, a whistle, a flashing light, or similar alerting device which can transmit a signal to the necessary persons would be acceptable. The purpose of the alarm is to alert persons that the system is operating, and that some type of planned action is necessary.
10. Sprinkler spacing. For a sprinkler system to be effective there must be an adequate discharge of water spray from the sprinkler head. Any obstructions which hinder the designed density or spray pattern of the water may create unprotected areas which can cause fire to spread. There are some sprinklers that, because of the system's design, are deflected to specific areas. This type of obstruction is acceptable if the system's design takes it into consideration in providing adequate coverage.
§ 1910.160 Fixed extinguishing systems, general.
1. Scope and application. This section contains the general requirements that are applicable to all fixed extinguishing systems installed to meet OSHA standards. It also applies to those fixed extinguishing systems, generally total flooding, which are not required by OSHA, but which, because of the agent's discharge, may expose employees to hazardous concentrations of extinguishing agents or combustion by-products. Employees who work around fixed extinguishing systems must be warned of the possible hazards associated with the system and its agent. For example, fixed dry chemical extinguishing systems may generate a large enough cloud of dry chemical particles that employees may become visually disoriented. Certain gaseous agents can expose employees to hazardous by-products of combustion when the agent comes into contact with hot metal or other hot surface. Some gaseous agents may be present in hazardous concentrations when the system has totally discharged because an extra rich concentration is necessary to extinguish deep-seated fires. Certain local application systems may be designed to discharge onto the flaming surface of a liquid, and it is possible that the liquid can splatter when hit with the discharging agent. All of these hazards must be determined before the system is placed into operation, and must be discussed with employees.
Based on the known toxicological effects of agents such as carbon tetrachloride and chlorobromomethane, OSHA is not permitting the use of these agents in areas where employees can be exposed to the agent or its side effects. However, chlorobromomethane has been accepted and may be used as an explosion suppression agent in unoccupied spaces. OSHA is permitting the use of this agent only in areas where employees will not be exposed.
2. Distinctive alarm signals. A distinctive alarm signal is required to indicate that a fixed system is discharging. Such a signal is necessary on those systems where it is not immediately apparent that the system is discharging. For example, certain gaseous agents make a loud noise when they discharge. In this case no alarm signal is necessary. However, where systems are located in remote locations or away from the general work area and where it is possible that a system could discharge without anyone knowing that it is doing so, then a distinctive alarm is necessary to warn employees of the hazards that may exist. The alarm can be a bell, gong, whistle, horn, flashing light, or any combination of signals as long as it is identifiable as a discharge alarm.
3. Maintenance. The employer is responsible for the maintenance of all fixed systems, but this responsibility does not preclude the use of outside contractors to do such work. New systems should be subjected to an acceptance test before placed in service. The employer should invite the installer, designer, insurance representative and others to witness the test. Problems found during the test need to be corrected before the system is considered operational.
4. Manual discharge stations. There are instances, such as for mechanical reasons and others, where the standards call for a manual back-up activation device. While the location of this device is not specified in the standard, the employer should assume that the device should be located where employees can easily reach it. It could, for example, be located along the main means of egress from the protected area so that employees could activate the system as they evacuate the work area.
5. Personal protective equipment. The employer is required to provide the necessary personal protective equipment to rescue employees who may be trapped in a totally flooded environment which may be hazardous to their health. This equipment would normally include a positive-pressure self-contained breathing apparatus and any necessary first aid equipment. In cases where the employer can assure the prompt arrival of the local fire department or plant emergency personnel which can provide the equipment, this can be considered as complying with the standards.
§ 1910.161 Fixed extinguishing systems, dry chemical.
1. Scope and application. The requirements of this section apply only to dry chemical systems. These requirements are to be used in conjunction with the requirements of § 1910.160.
2. Maintenance. The employer is responsible for assuring that dry chemical systems will operate effectively. To do this, periodic maintenance is necessary. One test that must be conducted during the maintenance check is one which will determine if the agent has remained free of moisture. If an agent absorbs any moisture, it may tend to cake and thereby clog the system. An easy test for acceptable moisture content is to take a lump of dry chemical from the container and drop it from a height of four inches. If the lump crumbles into fine particles, the agent is acceptable.
§ 1910.162 Fixed extinguishing systems, gaseous agent.
1. Scope and application. This section applies only to those systems which use gaseous agents. The requirements of § 1910.160 also apply to the gaseous agent systems covered in this section.
2. Design concentrations. Total flooding gaseous systems are based on the volume of gas which must be discharged in order to produce a certain designed concentration of gas in an enclosed area. The concentration needed to extinguish a fire depends on several factors including the type of fire hazard and the amount of gas expected to leak away from the area during discharge. At times it is necessary to “super-saturate” a work area to provide for expected leakage from the enclosed area. In such cases, employers must assure that the flooded area has been ventilated before employees are permitted to reenter the work area without protective clothing and respirators.
3. Toxic decomposition. Certain halogenated hydrocarbons will break down or decompose when they are combined with high temperatures found in the fire environment. The products of the decomposition can include toxic elements or compounds. For example, when Halon 1211 is placed into contact with hot metal it will break down and form bromide or fluoride fumes. The employer must find out which toxic products may result from decomposition of a particular agent from the manufacturer, and take the necessary precautions to prevent employee exposure to the hazard.
§ 1910.163 Fixed extinguishing systems, water spray and foam.
1. Scope and application. This section applies to those systems that use water spray or foam. The requirements of § 1910.160 also apply to this type of system.
2. Characteristics of foams. When selecting the type of foam for a specific hazard, the employer should consider the following limitations of some foams.
a. Some foams are not acceptable for use on fires involving flammable gases and liquefied gases with boiling points below ambient workplace temperatures. Other foams are not effective when used on fires involving polar solvent liquids.
b. Any agent using water as part of the mixture should not be used on fire involving combustible metals unless it is applied under proper conditions to reduce the temperature of burning metal below the ignition temperature. The employer should use only those foams that have been tested and accepted for this application by a recognized independent testing laboratory.
c. Certain types of foams may be incompatible and break down when they are mixed together.
d. For fires involving water miscible solvents, employers should use only those foams tested and approved for such use. Regular protein foams may not be effective on such solvents.
Whenever employers provide a foam or water spray system, drainage facilities must be provided to carry contaminated water or foam overflow away from the employee work areas and egress routes. This drainage system should drain to a central impounding area where it can be collected and disposed of properly. Other government agencies may have regulations concerning environmental considerations.
§ 1910.164 Fire detection systems.
1. Installation and restoration. Fire detection systems must be designed by knowledgeable engineers or other professionals, with expertise in fire detection systems and when the systems are installed, there should be an acceptance test performed on the system to insure it operates properly. The manufacturer's recommendations for system design should be consulted. While entire systems may not be approved, each component used in the system is required to be approved. Custom fire detection systems should be designed by knowledgeable fire protection or electrical engineers who are familiar with the workplace hazards and conditions. Some systems may only have one or two individual detectors for a small workplace, but good design and installation is still important. An acceptance test should be performed on all systems, including these smaller systems.
OSHA has a requirement that spare components used to replace those which may be destroyed during an alarm situation be available in sufficient quantities and locations for prompt restoration of the system. This does not mean that the parts or components have to be stored at the workplace. If the employer can assure that the supply of parts is available in the local community or the general metropolitan area of the workplace, then the requirements for storage and availability have been met. The intent is to make sure that the alarm system is fully operational when employees are occupying the workplace, and that when the system operates it can be returned to full service the next day or sooner.
2. Supervision. Fire detection systems should be supervised. The object of supervision is detection of any failure of the circuitry, and the employer should use any method that will assure that the system's circuits are operational. Electrically operated sensors for air pressure, fluid pressure, or electrical circuits, can provide effective monitoring and are the typical types of supervision.
3. Protection of fire detectors. Fire detectors must be protected from corrosion either by protective coatings, by being manufactured from non-corrosive materials or by location. Detectors must also be protected from mechanical impact damage, either by suitable cages or metal guards where such hazards are present, or by locating them above or out of contact with materials or equipment which may cause damage.
4. Number, location, and spacing of detectors. This information can be obtained from the approval listing for detectors or NFPA standards. It can also be obtained from fire protection engineers or consultants or manufacturers of equipment who have access to approval listings and design methods.
§ 1910.165 Employee alarm systems.
1. Scope and application. This section is intended to apply to employee alarm systems used for all types of employee emergencies except those which occur so quickly and at such a rapid rate (e.g., explosions) that any action by the employee is extremely limited following detection.
In small workplaces with 10 or less employees the alarm system can be by direct voice communication (shouting) where any one individual can quickly alert all other employees. Radio may be used to transmit alarms from remote workplaces where telephone service is not available, provided that radio messages will be monitored by emergency services, such as fire, police or others, to insure alarms are transmitted and received.
2. Alarm signal alternatives. In recognition of physically impaired individuals, OSHA is accepting various methods of giving alarm signals. For example, visual, tactile or audible alarm signals are acceptable methods for giving alarms to employees. Flashing lights or vibrating devices can be used in areas where the employer has hired employees with hearing or vision impairments. Vibrating devices, air fans, or other tactile devices can be used where visually and hearing impaired employees work. Employers are cautioned that certain frequencies of flashing lights have been claimed to initiate epileptic seizures in some employees and that this fact should be considered when selecting an alarm device. Two way radio communications would be most appropriate for transmitting emergency alarms in such workplaces which may be remote or where telephones may not be available.
3. Reporting alarms. Employee alarms may require different means of reporting, depending on the workplace involved. For example, in small workplaces, a simple shout throughout the workplace may be sufficient to warn employees of a fire or other emergency. In larger workplaces, more sophisticated equipment is necessary so that entire plants or high-rise buildings are not evacuated for one small emergency. In remote areas, such as pumping plants, radio communication with a central base station may be necessary. The goal of this standard is to assure that all employees who need to know that an emergency exists can be notified of the emergency. The method of transmitting the alarm should reflect the situation found at the workplace.
Personal radio transmitters, worn by an individual, can be used where the individual may be working such as in a remote location. Such personal radio transmitters shall send a distinct signal and should clearly indicate who is having an emergency, the location, and the nature of the emergency. All radio transmitters need a feedback system to assure that the emergency alarm is sent to the people who can provide assistance.
For multi-story buildings or single story buildings with interior walls for subdivisions, the more traditional alarm systems are recommended for these types of workplaces. Supervised telephone or manual fire alarm or pull box stations with paging systems to transmit messages throughout the building is the recommended alarm system. The alarm box stations should be available within a travel distance of 200 feet. Water flow detection on a sprinkler system, fire detection systems (guard's supervisory station) or tour signal (watchman's service), or other related systems may be part of the overall system. The paging system may be used for nonemergency operations provided the emergency messages and uses will have precedence over all other uses of the system.
4. Supervision. The requirements for supervising the employee alarm system circuitry and power supply may be accomplished in a variety of ways. Typically, electrically operated sensors for air pressure, fluid pressure, steam pressure, or electrical continuity of circuitry may be used to continuously monitor the system to assure it is operational and to identify trouble in the system and give a warning signal.
[45 FR 60715, Sept. 12, 1980; 46 FR 24557, May 1, 1981]
The following table contains a cross-reference listing of those current national consensus standards which contains information and guidelines that would be considered acceptable in complying with requirements in the specific sections of subpart L.
| Subpart L section | National consensus standard |
|---|---|
| 1910.156 | ANSI/NFPA No. 1972; Structural Fire Fighter's Helmets. |
| ANSI Z88.5 American National Standard, Practice for Respirator Protection for the Fire Service. | |
| ANSI/NFPA No. 1971, Protective Clothing for Structural Fire Fighters. | |
| NFPA No. 1041, Fire Service Instructor Professional Qualifications. | |
| 1910.157 | ANSI/NFPA No. 10, Portable Fire Extinguishers. |
| 1910.158 | ANSI/NFPA No. 18, Wetting Agents. |
| ANSI/NFPA No. 20, Centrifugal Fire Pumps. | |
| NFPA No. 21, Steam Fire Pumps. | |
| ANSI/NFPA No. 22, Water Tanks. | |
| NFPA No. 24, Outside Protection. | |
| NFPA No. 26, Supervision of Valves. | |
| NFPA No. 13E, Fire Department Operations in Properties Protected by Sprinkler, Standpipe Systems. | |
| ANSI/NFPA No. 194, Fire Hose Connections. | |
| NFPA No. 197, Initial Fire Attack, Training for. | |
| NFPA No. 1231, Water Supplies for Suburban and Rural Fire Fighting. | |
| 1910.159 | ANSI-NFPA No. 13, Sprinkler Systems. |
| NFPA No. 13A, Sprinkler Systems, Maintenance. | |
| ANSI/NFPA No. 18, Wetting Agents. | |
| ANSI/NFPA No. 20, Centrifugal Fire Pumps. | |
| ANSI/NFPA No. 22, Water Tanks. | |
| NFPA No. 24, Outside Protection. | |
| NFPA No. 26, Supervision of Valves. | |
| ANSI/NFPA No. 72B, Auxiliary Signaling Systems. | |
| NFPA No. 1231, Water Supplies for Suburban and Rural Fire Fighting. | |
| 1910.160 | ANSI/NFPA No. 11, Foam Systems. |
| ANSI/NFPA 11A, High Expansion Foam Extinguishing Systems. | |
| ANSI/NFPA No. 11B, Synthetic Foam and Combined Agent Systems. | |
| ANSI/NFPA No. 12, Carbon Dioxide Systems. | |
| ANSI/NFPA No. 12A, Halon 1301 Systems. | |
| ANSI/NFPA No. 12B, Halon 1211 Systems. | |
| ANSI/NFPA No. 15, Water Spray Systems. | |
| ANSI/NFPA 16 Foam-Water Spray Systems. | |
| ANSI/NFPA No. 17, Dry Chemical Systems. | |
| ANSI/NFPA 69, Explosion Suppression Systems. | |
| 1910.161 | ANSI/NFPA No. 11B, Synthetic Foam and Combined Agent Systems. |
| ANSI/NFPA No. 17, Dry Chemical Systems. | |
| 1910.162 | ANSI/NFPA No. 12, Carbon Dioxide Systems. |
| ANSI/NFPA No. 12A, Halon 1211 Systems. | |
| ANSI/NFPA No. 12B, Halon 1301 Systems. | |
| ANSI/NFPA No. 69, Explosion Suppression Systems. | |
| 1910.163 | ANSI/NFPA No. 11, Foam Extinguishing Systems. |
| ANSI/NFPA No. 11A, High Expansion Foam Extinguishing Systems. | |
| ANSI/NFPA No. 11B, Synthetic Foam and Combined Agent Systems. | |
| ANSI/NFPA No. 15, Water Spray Fixed Systems. | |
| ANSI/NFPA No. 16, Foam-Water Spray Systems. | |
| ANSI/NFPA No. 18, Wetting Agents. | |
| NFPA No. 26, Supervision of Valves. | |
| 1910.164 | ANSI/NFPA No. 71, Central Station Signaling Systems. |
| ANSI/NFPA No. 72A, Local Protective Signaling Systems. | |
| ANSI/NFPA No. 72B, Auxiliary Signaling Systems. | |
| ANSI/NFPA No. 72D, Proprietary Protective Signaling Systems. | |
| ANSI/NFPA No. 72E, Automatic Fire Detectors. | |
| ANSI/NFPA No. 101, Life Safety Code. | |
| 1910.165 | ANSI/NFPA No. 71, Central Station Signaling Systems. |
| ANSI/NFPA No. 72A, Local Protective Signaling Systems. | |
| ANSI/NFPA No. 72B, Auxiliary Protective Signaling Systems. | |
| ANSI/NFPA No. 72C, Remote Station Protective Signaling Systems. | |
| ANSI/NFPA No. 72D, Proprietary Protective Signaling Systems. | |
| ANSI/NFPA No. 101, Life Safety Code. | |
| Metric Conversion | ANSI/ASTM No. E380, American National Standard for Metric Practice. |
| NFPA standards are available from the National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. | |
| ANSI Standards are available from the American National Standards Institute, 1430 Broadway, New York, NY 10018. |
[45 FR 60715, Sept. 12, 1980, as amended at 58 FR 35309, June 30, 1993]
I. Appendix general references. The following references provide information which can be helpful in understanding the requirements contained in all of the sections of subpart L:
A. Fire Protection Handbook, National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
B. Accident Prevention Manual for Industrial Operations, National Safety Council; 425 North Michigan Avenue, Chicago, IL 60611.
C. Various associations also publish information which may be useful in understanding these standards. Examples of these associations are: Fire Equipment Manufacturers Association (FEMA) of Arlington, VA 22204 and the National Association of Fire Equipment Distributors (NAFED) of Chicago, IL 60601.
II. Appendix references applicable to individual sections. The following references are grouped according to individual sections contained in subpart L. These references provide information which may be helpful in understanding and implementing the standards of each section of subpart L.
A. § 1910.156. Fire brigades:
1. Private Fire Brigades, NFPA 27; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Initial Fire Attack, Training Standard On, NFPA 197; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Fire Fighter Professional Qualifications, NFPA 1001; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
4. Organization for Fire Services, NFPA 1201; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
5. Organization of a Fire Department, NFPA 1202; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
6. Protective Clothing for Structural Fire Fighting, ANSI/NFPA 1971;.
7. American National Standard for Men's Safety-Toe Footwear, ANSI Z41.1; American National Standards Institute, New York, NY 10018.
8. American National Standard for Occupational and Educational Eye and Face Protection, ANSI Z87.1; American National Standards Institute, New York, NY 10018.
9. American National Standard, Safety Requirements for Industrial Head Protection, ANSI Z89.1; American National Standards Institute, New York, NY 10018.
10. Specifications for Protective Headgear for Vehicular Users, ANSI Z90.1; American National Standards Institute, New York, NY 10018.
11. Testing Physical Fitness; Davis and Santa Maria. Fire Command. April 1975.
12. Development of a Job-Related Physical Performance Examination for Fire Fighters; Dotson and Others. A summary report for the National Fire Prevention and Control Administration. Washington, DC. March 1977.
13. Proposed Sample Standards for Fire Fighters' Protective Clothing and Equipment; International Association of Fire Fighters, Washington, DC.
14. A Study of Facepiece Leakage of Self-Contained Breathing Apparatus by DOP Man Tests; Los Alamos Scientific Laboratory, Los Alamos, NM.
15. The Development of Criteria for Fire Fighters' Gloves; Vol. II: Glove Criteria and Test Methods; National Institute for Occupational Safety and Health, Cincinnati, OH. 1976.
16. Model Performance Criteria for Structural Fire Fighters' Helmets; National Fire Prevention and Control Administration, Washington, DC. 1977.
17. Firefighters; Job Safety and Health Magazine, Occupational Safety and Health Administration, Washington, DC. June 1978.
18. Eating Smoke—The Dispensable Diet; Utech, H.P. The Fire Independent, 1975.
19. Project Monoxide—A Medical Study of an Occupational Hazard of Fire Fighters; International Association of Fire Fighters, Washington, DC.
20. Occupational Exposures to Carbon Monoxide in Baltimore Firefighters; Radford and Levine. Johns Hopkins University, Baltimore, MD. Journal of Occupational Medicine, September, 1976.
21. Fire Brigades; National Safety Council, Chicago, IL. 1966.
22. American National Standard, Practice for Respiratory Protection for the Fire Service; ANSI Z88.5; American National Standards Institute, New York, NY 10018.
23. Respirator Studies for the Nuclear Regulatory Commission; October 1, 1977—September 30, 1978. Evaluation and Performance of Open Circuit Breathing Apparatus. NU REG/CR-1235. Los Alamos Scientific Laboratory; Los Alamos, NM. 87545, January, 1980.
B. § 1910.157. Portable fire extinguishers:
1. Standard for Portable Fire Extinguishers, ANSI/NFPA 10; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269
2. Methods for Hydrostatic Testing of Compressed Gas Cylinders, C-1; Compressed Gas Association, 1235 Jefferson Davis Highway, Arlington, VA 22202.
3. Recommendations for the Disposition of Unserviceable Compressed Gas Cylinders, C-2; Compressed Gas Association, 1235 Jefferson Davis Highway, Arlington, VA 22202.
4. Standard for Visual Inspection of Compressed Gas Cylinders, C-6; Compressed Gas Association, 1235 Jefferson Davis Highway, Arlington, VA 22202.
5. Portable Fire Extinguisher Selection Guide, National Association of Fire Equipment Distributors; 111 East Wacker Drive, Chicago, IL 60601.
C. § 1910.158. Standpipe and hose systems:
1. Standard for the Installation of Sprinkler Systems, ANSI/NFPA 13; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Standard of the Installation of Standpipe and Hose Systems, ANSI/NFPA 14; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard for the Installation of Centrifugal Fire Pumps, ANSI/NFPA 20; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
4. Standard for Water Tanks for Private Fire Protection, ANSI/NFPA 22; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
5. Standard for Screw Threads and Gaskets for Fire Hose Connections, ANSI/NFPA 194; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
6. Standard for Fire Hose, NFPA 196; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
7. Standard for the Care of Fire Hose, NFPA 198; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
D. § 1910.159. Automatic sprinkler systems:
1. Standard of the Installation of Sprinkler Systems, ANSI-NFPA 13; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Standard for the Care and Maintenance of Sprinkler Systems, ANSI/NFPA 13A; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard for the Installation of Standpipe and Hose Systems, ANSI/NFPA 14; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
4. Standard for the Installation of Centrifugal Fire Pumps, ANSI/NFPA 20; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
5. Standard for Water Tanks for Private Fire Protection, ANSI-NFPA 22; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
6. Standard for Indoor General Storage, ANSI/NFPA 231; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
7. Standard for Rack Storage of Materials, ANSI/NFPA 231C; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
E. § 1910.160. Fixed extinguishing systems—general information:
1. Standard for Foam Extinguishing Systems, ANSI-NFPA 11; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Standard for Hi-Expansion Foam Systems, ANSI/NFPA 11A; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard on Synthetic Foam and Combined Agent Systems, ANSI/NFPA 11B; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
4. Standard on Carbon Dioxide Extinguishing Systems, ANSI/NFPA 12; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
5. Standard on Halon 1301, ANSI/NFPA 12A; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
6. Standard on Halon 1211, ANSI/NFPA 12B; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
7. Standard for Water Spray Systems, ANSI/NFPA 15; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
8. Standard for Foam-Water Sprinkler Systems and Foam-Water Spray Systems, ANSI/NFPA 16; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269
9. Standard for Dry Chemical Extinguishing Systems, ANSI/NFPA 17; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
F. § 1910.161. Fixed extinguishing systems—dry chemical:
1. Standard for Dry Chemical Extinguishing Systems, ANSI/NFPA 17; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. National Electrical Code, ANSI/NFPA 70; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard for the Installation of Equipment for the Removal of Smoke and Grease-Laden Vapor from Commercial Cooking Equipment, NFPA 96; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
G. § 1910.162. Fixed extinguishing systems—gaseous agents:
1. Standard on Carbon Dioxide Extinguishing Systems, ANSI/NFPA 12; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Standard on Halon 1301, ANSI/NFPA 12B; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard on Halon 1211, ANSI/NFPA 12B; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
4. Standard on Explosion Prevention Systems, ANSI/NFPA 69; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
5. National Electrical Code, ANSI/NFPA 70; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
6. Standard on Automatic Fire Detectors, ANSI/NFPA 72E; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
7. Determination of Halon 1301/1211 Threshold Extinguishing Concentrations Using the Cup Burner Method; Riley and Olson, Ansul Report AL-530-A.
H. § 1910.163. Fixed extinguishing systems—water spray and foam agents:
1. Standard for Foam Extinguisher Systems, ANSI/NFPA 11; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Standard for High Expansion Foam Systems, ANSI/NFPA 11A; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard for Water Spray Fixed Systems for Fire Protection, ANSI/NFPA 15; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
4. Standard for the Installation of Foam-Water Sprinkler Systems and Foam-Water Spray Systems, ANSI/NFPA 16; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
I. § 1910.164. Fire Detection systems:
1. National Electrical Code, ANSI/NFPA 70; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Standard for Central Station Signaling Systems, ANSI/NFPA 71; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard on Automatic Fire Detectors, ANSI/NFPA 72E; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
J. § 1910.165. Employee alarm systems:
1. National Electrical Code, ANSI/NFPA 70; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
2. Standard for Central Station Signaling systems, ANSI/NFPA 71; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
3. Standard for Local Protective Signaling Systems, ANSI/NFPA 72A; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
4. Standard for Auxiliary Protective Signaling Systems, ANSI/NFPA 72B; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
5. Standard for Remote Station Protective Signaling Systems, ANSI/NFPA 72C; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
6. Standard for Proprietary Protective Signaling Systems, ANSI/NFPA 72D; National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
7. Vocal Emergency Alarms in Hospitals and Nursing Facilities: Practice and Potential. National Bureau of Standards. Washington, D.C., July 1977.
8. Fire Alarm and Communication Systems. National Bureau of Standards. Washington, D.C., April 1978.
[45 FR 60715, Sept. 12, 1980, as amended at 58 FR 35309, June 30, 1993]
The final standard for fire brigades, section 1910.156, contains provisions which incorporate certain publications by reference. The publications provide criteria and test methods for protective clothing worn by those fire brigade members who are expected to perform interior structural fire fighting. The standard references the publications as the chief sources of information for determining if the protective clothing affords the required level of protection.
It is appropriate to note that the final standard does not require employers to purchase a copy of the referenced publications. Instead, employers can specify (in purchase orders to the manufacturers) that the protective clothing meet the criteria and test methods contained in the referenced publications and can rely on the manufacturers' assurances of compliance. Employers, however, may desire to obtain a copy of the referenced publications for their own information.
The paragraph designation of the standard where the referenced publications appear, the title of the publications, and the availablity of the publications are as follows:
| Paragraph designation | Referenced publication | Available from |
|---|---|---|
| 1910.156(e)(3)(ii) | “Protective Clothing for Structural Fire Fighting,” NFPA No. 1971 (1975) | National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. |
| 1910.156(e)(4)(i) | “Development of Criteria for Fire Fighter's Gloves; Vol. II, Part II: Test Methods” (1976) | U.S. Government Printing Office, Washington, D.C. 20402. Stock No. for Vol. II is: 071-033-0201-1. |
| 1910.156(e)(5)(i) | “Model Performance Criteria for Structural Firefighter's Helmets” (1977) | U.S. Fire Administration, National Fire Safety and Research Office, Washington, D.C. 20230. |
The referenced publications (or a microfiche of the publications) are available for review at many universities and public libraries throughout the country. These publications may also be examined at the OSHA Technical Data Center, Room N2439-Rear, United States Department of Labor, 200 Constitution Ave., N.W., Washington, D.C. 20210 (202-219-7500), or at any OSHA Regional Office (see telephone directories under United States Government-Labor Department).
[45 FR 60715, Sept. 12, 1980, as amended at 58 FR 33509, June 30, 1993; 61 FR 9239, Mar. 7, 1996]
This appendix contains test methods which must be used to determine if protective clothing affords the required level of protection as specified in § 1910.156, fire brigades.
A. Apparatus. The puncture resistance test shall be performed on a testing machine having a movable platform adjusted to travel at 1/4 -inch/min (0.1 cm/sec). Two blocks of hardwood, metal, or plastic shall be prepared as follows: the blocks shall be of such size and thickness as to insure a suitable rigid test ensemble and allow for at least one-inch of the pointed end of an 8D nail to be exposed for the penetration. One block shall have a hole drilled to hold an 8D common nail firmly at an angle of 98°. The second block shall have a maximum 1/2 -inch (1.3 cm) diameter hole drilled through it so that the hole will allow free passage of the nail after it penetrates the insole during the test.
B. Procedure. The test ensemble consisting of the sample unit, the two prepared blocks, a piece of leather outsole 10 to 11 irons thick, and a new 8D nail, shall be placed as follows: the 8D nail in the hole, the sample of outsole stock superimposed above the nail, the area of the sole plate to be tested placed on the outsole, and the second block with hole so placed as to allow for free passage of the nail after it passes through the outsole stock and sole plate in that order. The machine shall be started and the pressure, in pounds required for the nail to completely penetrate the outsole and sole plate, recorded to the nearest five pounds. Two determinations shall be made on each sole plate and the results averaged. A new nail shall be used for each determination.
C. Source. These test requirements are contained in “Military Specification For Fireman's Boots,” MIL-B-2885D (1973 and amendment dated 1975) and are reproduced for your convenience.
A. Test specimen. The specimen shall be a rectangle of cloth 3-inches by 6-inches (7.6 cm by 15.2 cm). The long dimension shall be parallel to the warp for warp tests and parallel to the filling for filling tests. No two specimens for warp tests shall contain the same warp yarns, nor shall any two specimens for filling tests contain the same filling yarns. The specimen shall be taken no nearer the selvage than 1/10 the width of the cloth. An isosceles trapezoid having an altitude of 3-inches (7.6 cm) and bases of 1 inch (2.5cm) and 4 inches (10.2 cm) in length, respectively, shall be marked on each specimen, preferably with the aid of a template. A cut approximately 3/8 -inch (1 cm) in length shall then be made in the center of a perpendicular to the 1-inch (2.5 cm) edge.
B. Apparatus.
Each jaw face shall have a flat smooth, gripping surface. All edges which might cause a cutting action shall be rounded to a radius of not over 1/64 -inch (.04 cm). In cases where a cloth tends to slip when being tested, the jaws may be faced with rubber or other material to prevent slippage. The distance between the jaws (gage length) shall be one-inch at the start of the test.
C. Procedure.
D. Report.
E. Source. These test requirements are contained in “Federal Test Method Standard 191, Method 5136” and are reproduced for your convenience.
A. Test specimen. The specimen shall be a rectangle of cloth 2 3/4 inches (7.0 cm) by 12 inches (30.5 cm) with the long dimension parallel to either the warp or filling direction of the cloth. No two warp specimens shall contain the same warp yarns, and no two filling specimens shall contain the same filling yarn.
B. Number of determinations. Five specimens from each of the warp and filling directions shall be tested from each sample unit.
C. Apparatus.
A cabinet and accessories shall be fabricated in accordance with the requirements specified in Figures L-1, L-2, and L-3. Galvanized sheet metal or other suitable metal shall be used. The entire inside back wall of the cabinet shall be painted black to facilitate the viewing of the test specimen and pilot flame.
The burner shall be equipped with a variable orifice to adjust the flame height, a barrel having a 3/8 -inch (1 cm) inside diameter and a pilot light.
D. Procedure.
The burner flame shall be adjusted by means of the needle valve in the base of the burner to give a flame height of 1 1/2 inches (3.8 cm) with the stopcock fully open and the air supply to the burner shut off and taped. The 1 1/2 -inch (3.8 cm) flame height is obtained by adjusting the valve so that the uppermost portion (tip) of the flame is level with the tip of the metal prong (see Figure L-2) specified for adjustment of flame height. It is an important aspect of the evaluation that the flame height be adjusted with the tip of the flame level with the tip of the metal prong. After inserting the specimen, the stopcock shall be fully opened, and the burner flame applied vertically at the middle of the lower edge of the specimen for 12 seconds and the burner turned off. The cabinet door shall remain shut during testing.
Loads for determining char length applicable to the weight of the test cloth shall be as shown in Table L-2.
| Specified weight per square yard of cloth before any fire retardant treatment or coating—ounces | Total tearing weight for determining the charred length—pound |
|---|---|
| 2.0 to 6.0 | 0.25 |
| Over 6.0 to 15.0 | 0.50 |
| Over 15.0 to 23.0 | 0.75 |
| Over 23.0 | 1.0 |
| 1 To change into S.I. (System International) units, 1 ounce = 28.35 grams, 1 pound = 453 grams, 1 yard = .91 metre. |
E. Report.
F. Source. These test requirements are contained in “Federal Test Method Standard 191, Method 5903 (1971)” and are reproduced for your convenience.
[45 FR 60715, Sept. 12, 1980; 46 FR 24557, May 1, 1981]
This section applies to compressed air receivers, and other equipment used in providing and utilizing compressed air for performing operations such as cleaning, drilling, hoisting, and chipping. On the other hand, however, this section does not deal with the special problems created by using compressed air to convey materials nor the problems created when men work in compressed air as in tunnels and caissons. This section is not intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment.
Air receivers shall be so installed that all drains, handholes, and manholes therein are easily accessible. Under no circumstances shall an air receiver be buried underground or located in an inaccessible place.
A drain pipe and valve shall be installed at the lowest point of every air receiver to provide for the removal of accumulated oil and water. Adequate automatic traps may be installed in addition to drain valves. The drain valve on the air receiver shall be opened and the receiver completely drained frequently and at such intervals as to prevent the accumulation of excessive amounts of liquid in the receiver.
[39 FR 23502, June 27, 1974, as amended at 49 FR 5322, Feb. 10, 1984; 61 FR 9239, Mar. 7, 1996]
Where mechanical handling equipment is used, sufficient safe clearances shall be allowed for aisles, at loading docks, through doorways and wherever turns or passage must be made. Aisles and passageways shall be kept clear and in good repair, with no obstruction across or in aisles that could create a hazard. Permanent aisles and passageways shall be appropriately marked.
Storage of material shall not create a hazard. Bags, containers, bundles, etc., stored in tiers shall be stacked, blocked, interlocked and limited in height so that they are stable and secure against sliding or collapse.
Storage areas shall be kept free from accumulation of materials that constitute hazards from tripping, fire, explosion, or pest harborage. Vegetation control will be exercised when necessary.
Clearance signs to warn of clearance limits shall be provided.
Derail and/or bumper blocks shall be provided on spur railroad tracks where a rolling car could contact other cars being worked, enter a building, work or traffic area.
Covers and/or guardrails shall be provided to protect personnel from the hazards of open pits, tanks, vats, ditches, etc.
[39 FR 23052, June 27, 1974, as amended at 43 FR 49749, Oct. 24, 1978]
Barrier means a fence, wall or other structure or object placed between a single piece rim wheel and an employee during tire inflation, to contain the rim wheel components in the event of the sudden release of the contained air of the single piece rim wheel.
Charts means the U.S. Department of Labor, Occupational Safety and Health Administration publications entitled “Demounting and Mounting Procedures for Tube-Type Truck and Bus Tires,” “Demounting and Mounting Procedures for Tubeless Truck and Bus Tires,” and “Multi-Piece Rim Matching Chart.” These charts may be in manual or poster form. OSHA also will accept any other manual or poster that provides at least the same instructions, safety precautions, and other information contained in these publications, which is applicable to the types of wheels the employer is servicing.
Installing a rim wheel means the transfer and attachment of an assembled rim wheel onto a vehicle axle hub. Removing means the opposite of installing.
Mounting a tire means the assembly or putting together of the wheel and tire components to form a rim wheel, including inflation. Demounting means the opposite of mounting.
Multi-piece rim wheel means the assemblage of a multi-piece wheel with the tire tube and other components.
Multi-piece wheel means a vehicle wheel consisting of two or more parts, one of which is a side or locking ring designed to hold the tire on the wheel by interlocking components when the tire is inflated.
Restraining device means an apparatus such as a cage, rack, assemblage of bars and other components that will constrain all rim wheel components during an explosive separation of a multi-piece rim wheel, or during the sudden release of the contained air of a single piece rim wheel.
Rim manual means a publication containing instructions from the manufacturer or other qualified organization for correct mounting, demounting, maintenance, and safety precautions peculiar to the type of wheel being serviced.
Rim wheel means an assemblage of tire, tube and liner (where appropriate), and wheel components.
Service or servicing means the mounting and demounting of rim wheels, and related activities such as inflating, deflating, installing, removing, and handling.
Service area means that part of an employer's premises used for the servicing of rim wheels, or any other place where an employee services rim wheels.
Single piece rim wheel means the assemblage of single piece rim wheel with the tire and other components.
Single piece wheel means a vehicle wheel consisting of one part, designed to hold the tire on the wheel when the tire is inflated.
Trajectory means any potential path or route that a rim wheel component may travel during an explosive separation, or the sudden release of the pressurized air, or an area at which an airblast from a single piece rim wheel may be released. The trajectory may deviate from paths which are perpendicular to the assembled position of the rim wheel at the time of separation or explosion. (See appendix A for examples of trajectories.)
Wheel means that portion of a rim wheel which provides the method of attachment of the assembly to the axle of a vehicle and also provides the means to contain the inflated portion of the assembly (i.e., the tire and/or tube).
The employer shall establish a safe operating procedure for servicing multi-piece rim wheels and shall assure that employees are instructed in and follow that procedure. The procedure shall include at least the following elements:
The employer shall establish a safe operating procedure for servicing single piece rim wheels and shall assure that employees are instructed in and follow that procedure. The procedure shall include at least the following elements:
Appendix B to § 1910.177—Ordering Information for the OSHA Charts
The information on the OSHA charts is available on three posters, or in a manual containing the three charts, entitled “Demounting and Mounting Procedures for Tubeless Truck and Bus Tires,” “Demounting and Mounting Procedures for Tube-Type Truck and Bus Tires,” and “Multi-piece Rim Matching Chart.” Interested parties can download and print both the manuals and posters from OSHA's Web site at http://www.osha.gov/publications (and type “tire chart” in the search field). However, when used by the employer at a worksite to provide information to employees, the printed posters must be, at a minimum, 2 feet wide and 3 feet long. Copies of the manual also are available from the Occupational Safety and Health Administration (OSHA Office of Publications, Room N-3101, U.S. Department of Labor, 200 Constitution Avenue NW., Washington, DC 20210; telephone: (202) 693-1888; or fax: (202) 693-2498).
[49 FR 4350, Feb. 3, 1984, as amended at 52 FR 36026, Sept. 25, 1987; 53 FR 34737, Sept. 8, 1988; 61 FR 9239, Mar. 7, 1996; 76 FR 24698, May 2, 2011; 76 FR 80739, Dec. 27, 2011]
For the purpose of this standard there are eleven different designations of industrial trucks or tractors as follows: D, DS, DY, E, ES, EE, EX, G, GS, LP, and LPS.
| Classes | Unclassified | Class I locations | Class II locations | Class III locations |
|---|---|---|---|---|
| Description of classes | Locations not possessing atmospheres as described in other columns | Locations in which flammable gases or vapors are, or may be, present in the air in quantities sufficient to produce explosive or ignitible mixtures | Locations which are hazardous because of the presence of combustible dust | Locations where easily ignitible fibers or flyings are present but not likely to be in suspension in quantities sufficient to produce ignitible mixtures. |
| Groups in classes | None | A | B | C | D | E | F | G | None |
|---|---|---|---|---|---|---|---|---|---|
| Examples of locations or atmospheres in classes and groups | Piers and wharves inside and outside general storage, general industrial or commercial properties | Acetylene | Hydrogen | Ethyl ether | Gasoline Naphtha Alcohols Acetone Lacquer solvent Benzene | Metal dust | Carbon black coal dust, coke dust | Grain dust, flour dust, starch dust, organic dust | Baled waste, cocoa fiber, cotton, excelsior, hemp, istle, jute, kapok, oakum, sisal, Spanish moss, synthetic fibers, tow. |
| 1 | 2 | 1 | 2 | 1 | 2 | ||
|---|---|---|---|---|---|---|---|
| Divisions (nature of hazardous conditions) | None | Above condition exists continuously, intermittently, or periodically under normal operating conditions | Above condition may occur accidentally as due to a puncture of a storage drum | Explosive mixture may be present under normal operating conditions, or where failure of equipment may cause the condition to exist simultaneously with arcing or sparking of electrical equipment, or where dusts of an electrically conducting nature may be present | Explosive mixture not normally present, but where deposits of dust may cause heat rise in electrical equipment, or where such deposits may be ignited by arcs or sparks from electrical equipment | Locations in which easily ignitible fibers or materials producing combustible flyings are handled, manufactured, or used | Locations in which easily ignitible fibers are stored or handled (except in the process of manufacture). |
| Authorized uses of trucks by types in groups of classes and divisions | |||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Groups in classes | None | A | B | C | D | A | B | C | D | E | F | G | E | F | G | None | None |
| Type of truck authorized: | |||||||||||||||||
| Diesel: | |||||||||||||||||
| Type D | D** | ||||||||||||||||
| Type DS | DS | DS | DS | ||||||||||||||
| Type DY | DY | DY | DY | DY | |||||||||||||
| Electric: | |||||||||||||||||
| Type E | E** | E | |||||||||||||||
| Type ES | ES | ES | ES | ||||||||||||||
| Type EE | EE | EE | EE | EE | |||||||||||||
| Type EX | EX | EX | EX | EX | EX | EX | EX | ||||||||||
| Gasoline: | |||||||||||||||||
| Type G | G** | ||||||||||||||||
| Type GS | GS | GS | GS | ||||||||||||||
| LP-Gas: | |||||||||||||||||
| Type LP | LP** | ||||||||||||||||
| Type LPS | LPS | LPS | LPS | ||||||||||||||
| Paragraph Ref. in No. 505 | 210.211 | 201 (a) | 203 (a) | 209 (a) | 204 (a), (b) | 202 (a) | 205 (a) | 209 (a) | 206 (a), (b) | 207(a) | 208 (a) | ||||||
| **Trucks conforming to these types may also be used—see subdivision (c)(2)(x) and (c)(2)(xii) of this section. |
Power-operated industrial trucks that have been originally approved for the use of gasoline for fuel, when converted to the use of liquefied petroleum gas fuel in accordance with paragraph (q) of this section, may be used in those locations where G, GS or LP, and LPS designated trucks have been specified in the preceding paragraphs.
See subpart D of this part.
Powered industrial truck operators shall receive initial training in the following topics, except in topics which the employer can demonstrate are not applicable to safe operation of the truck in the employer's workplace.
where they are located, what they do, and how they work;
If an operator has previously received training in a topic specified in paragraph (l)(3) of this section, and such training is appropriate to the truck and working conditions encountered, additional training in that topic is not required if the operator has been evaluated and found competent to operate the truck safely.
The employer shall certify that each operator has been trained and evaluated as required by this paragraph (l). The certification shall include the name of the operator, the date of the training, the date of the evaluation, and the identity of the person(s) performing the training or evaluation.
The employer shall ensure that operators of powered industrial trucks are trained, as appropriate, by the dates shown in the following table.
| If the employee was hired: | The initial training and evaluation of that employee must be completed: |
|---|---|
| Before December 1, 1999 | By December 1, 1999. |
| After December 1, 1999 | Before the employee is assigned to operate a powered industrial truck. |
Where industrial trucks are used on a round-the-clock basis, they shall be examined after each shift. Defects when found shall be immediately reported and corrected.
Appendix A to § 1910.178—Stability of Powered Industrial Trucks (Non-mandatory Appendix to Paragraph ( l ) of This Section)
A-1. Definitions. The following definitions help to explain the principle of stability:
Center of gravity is the point on an object at which all of the object's weight is concentrated. For symmetrical loads, the center of gravity is at the middle of the load.
Counterweight is the weight that is built into the truck's basic structure and is used to offset the load's weight and to maximize the vehicle's resistance to tipping over.
Fulcrum is the truck's axis of rotation when it tips over.
Grade is the slope of a surface, which is usually measured as the number of feet of rise or fall over a hundred foot horizontal distance (the slope is expressed as a percent).
Lateral stability is a truck's resistance to overturning sideways.
Line of action is an imaginary vertical line through an object's center of gravity.
Load center is the horizontal distance from the load's edge (or the fork's or other attachment's vertical face) to the line of action through the load's center of gravity.
Longitudinal stability is the truck's resistance to overturning forward or rearward.
Moment is the product of the object's weight times the distance from a fixed point (usually the fulcrum). In the case of a powered industrial truck, the distance is measured from the point at which the truck will tip over to the object's line of action. The distance is always measured perpendicular to the line of action.
Track is the distance between the wheels on the same axle of the truck.
Wheelbase is the distance between the centerline of the vehicle's front and rear wheels.
A-2. General.
A-2.1. Determining the stability of a powered industrial truck is simple once a few basic principles are understood. There are many factors that contribute to a vehicle's stability: the vehicle's wheelbase, track, and height; the load's weight distribution; and the vehicle's counterweight location (if the vehicle is so equipped).
A-2.2. The “stability triangle,” used in most stability discussions, demonstrates stability simply.
A-3. Basic Principles.
A-3.1. Whether an object is stable depends on the object's moment at one end of a system being greater than, equal to, or smaller than the object's moment at the system's other end. This principle can be seen in the way a see-saw or teeter-totter works: that is, if the product of the load and distance from the fulcrum (moment) is equal to the moment at the device's other end, the device is balanced and it will not move. However, if there is a greater moment at one end of the device, the device will try to move downward at the end with the greater moment.
A-3.2. The longitudinal stability of a counterbalanced powered industrial truck depends on the vehicle's moment and the load's moment. In other words, if the mathematic product of the load moment (the distance from the front wheels, the approximate point at which the vehicle would tip forward) to the load's center of gravity times the load's weight is less than the vehicle's moment, the system is balanced and will not tip forward. However, if the load's moment is greater than the vehicle's moment, the greater load-moment will force the truck to tip forward.
A-4. The Stability Triangle.
A-4.1. Almost all counterbalanced powered industrial trucks have a three-point suspension system, that is, the vehicle is supported at three points. This is true even if the vehicle has four wheels. The truck's steer axle is attached to the truck by a pivot pin in the axle's center. When the points are connected with imaginary lines, this three-point support forms a triangle called the stability triangle. Figure 1 depicts the stability triangle.
A-4.2. When the vehicle's line of action, or load center, falls within the stability triangle, the vehicle is stable and will not tip over. However, when the vehicle's line of action or the vehicle/load combination falls outside the stability triangle, the vehicle is unstable and may tip over. (See Figure 2.)
A-5.1. The axis of rotation when a truck tips forward is the front wheels' points of contact with the pavement. When a powered industrial truck tips forward, the truck will rotate about this line. When a truck is stable, the vehicle-moment must exceed the load-moment. As long as the vehicle-moment is equal to or exceeds the load-moment, the vehicle will not tip over. On the other hand, if the load moment slightly exceeds the vehicle-moment, the truck will begin to tip forward, thereby causing the rear to lose contact with the floor or ground and resulting in loss of steering control. If the load-moment greatly exceeds the vehicle moment, the truck will tip forward.
A-5.2. To determine the maximum safe load-moment, the truck manufacturer normally rates the truck at a maximum load at a given distance from the front face of the forks. The specified distance from the front face of the forks to the line of action of the load is commonly called the load center. Because larger trucks normally handle loads that are physically larger, these vehicles have greater load centers. Trucks with a capacity of 30,000 pounds or less are normally rated at a given load weight at a 24-inch load center. Trucks with a capacity greater than 30,000 pounds are normally rated at a given load weight at a 36- or 48-inch load center. To safely operate the vehicle, the operator should always check the data plate to determine the maximum allowable weight at the rated load center.
A-5.3. Although the true load-moment distance is measured from the front wheels, this distance is greater than the distance from the front face of the forks. Calculating the maximum allowable load-moment using the load-center distance always provides a lower load-moment than the truck was designed to handle. When handling unusual loads, such as those that are larger than 48 inches long (the center of gravity is greater than 24 inches) or that have an offset center of gravity, etc., a maximum allowable load-moment should be calculated and used to determine whether a load can be safely handled. For example, if an operator is operating a 3000 pound capacity truck (with a 24-inch load center), the maximum allowable load-moment is 72,000 inch-pounds (3,000 times 24). If a load is 60 inches long (30-inch load center), then the maximum that this load can weigh is 2,400 pounds (72,000 divided by 30).
A-6. Lateral Stability.
A-6.1. The vehicle's lateral stability is determined by the line of action's position (a vertical line that passes through the combined vehicle's and load's center of gravity) relative to the stability triangle. When the vehicle is not loaded, the truck's center of gravity location is the only factor to be considered in determining the truck's stability. As long as the line of action of the combined vehicle's and load's center of gravity falls within the stability triangle, the truck is stable and will not tip over. However, if the line of action falls outside the stability triangle, the truck is not stable and may tip over. Refer to Figure 2.
A-6.2. Factors that affect the vehicle's lateral stability include the load's placement on the truck, the height of the load above the surface on which the vehicle is operating, and the vehicle's degree of lean.
A-7. Dynamic Stability.
A-7.1. Up to this point, the stability of a powered industrial truck has been discussed without considering the dynamic forces that result when the vehicle and load are put into motion. The weight's transfer and the resultant shift in the center of gravity due to the dynamic forces created when the machine is moving, braking, cornering, lifting, tilting, and lowering loads, etc., are important stability considerations.
A-7.2. When determining whether a load can be safely handled, the operator should exercise extra caution when handling loads that cause the vehicle to approach its maximum design characteristics. For example, if an operator must handle a maximum load, the load should be carried at the lowest position possible, the truck should be accelerated slowly and evenly, and the forks should be tilted forward cautiously. However, no precise rules can be formulated to cover all of these eventualities.
[39 FR 23502, June 27, 1974, as amended at 40 FR 23073, May 28, 1975; 43 FR 49749, Oct. 24, 1978; 49 FR 5322, Feb. 10, 1984; 53 FR 12122, Apr. 12, 1988; 55 FR 32015, Aug. 6, 1990; 61 FR 9239, Mar. 7, 1996; 63 FR 66270, Dec. 1, 1998; 68 FR 32638, June 2, 2003; 71 FR 16672, Apr. 3, 2006; 81 FR 83005, Nov. 18, 2016]
means the American National Standards Institute.
This section applies to overhead and gantry cranes, including semigantry, cantilever gantry, wall cranes, storage bridge cranes, and others having the same fundamental characteristics. These cranes are grouped because they all have trolleys and similar travel characteristics.
All new overhead and gantry cranes constructed and installed on or after August 31, 1971, shall meet the design specifications of the American National Standard Safety Code for Overhead and Gantry Cranes, ANSI B30.2.0-1967, which is incorporated by reference as specified in § 1910.6.
Cranes may be modified and rerated provided such modifications and the supporting structure are checked thoroughly for the new rated load by a qualified engineer or the equipment manufacturer. The crane shall be tested in accordance with paragraph (k)(2) of this section. New rated load shall be displayed in accordance with subparagraph (5) of this paragraph.
Outdoor storage bridges shall be provided with automatic rail clamps. A wind-indicating device shall be provided which will give a visible or audible alarm to the bridge operator at a predetermined wind velocity. If the clamps act on the rail heads, any beads or weld flash on the rail heads shall be ground off.
The rated load of the crane shall be plainly marked on each side of the crane, and if the crane has more than one hoisting unit, each hoist shall have its rated load marked on it or its load block and this marking shall be clearly legible from the ground or floor.
If the runways of two cranes are parallel, and there are no intervening walls or structure, there shall be adequate clearance provided and maintained between the two bridges.
Access to the car and/or bridge walkway shall be by a conveniently placed fixed ladder, stairs, or platform requiring no step over any gap exceeding 12 inches (30 cm). Fixed ladders must comply with subpart D of this part.
Carbon tetrachloride extinguishers shall not be used.
Light in the cab shall be sufficient to enable the operator to see clearly enough to perform his work.
Toeboards and handrails must comply with subpart D of this part.
Bridge trucks shall be equipped with sweeps which extend below the top of the rail and project in front of the truck wheels.
Conductors of the open type mounted on the crane runway beams or overhead shall be so located or so guarded that persons entering or leaving the cab or crane footwalk normally could not come into contact with them.
If a service receptacle is provided in the cab or on the bridge of cab-operated cranes, it shall be a grounded three-prong type permanent receptacle, not exceeding 300 volts.
[Reserved]
If a load is supported by more than one part of rope, the tension in the parts shall be equalized.
Hooks shall meet the manufacturer's recommendations and shall not be overloaded.
Except for floor-operated cranes a gong or other effective warning signal shall be provided for each crane equipped with a power traveling mechanism.
Prior to initial use all new and altered cranes shall be inspected to insure compliance with the provisions of this section.
The following items shall be inspected for defects at intervals as defined in paragraph (j)(1)(ii) of this section or as specifically indicated, including observation during operation for any defects which might appear between regular inspections. All deficiencies such as listed shall be carefully examined and determination made as to whether they constitute a safety hazard:
Visual inspection daily; monthly inspection with a certification record which includes the date of inspection, the signature of the person who performed the inspection and the serial number, or other identifier, of the hook inspected. For hooks with cracks or having more than 15 percent in excess of normal throat opening or more than 10° twist from the plane of the unbent hook refer to paragraph (l)(3)(iii)( a ) of this section.
Complete inspections of the crane shall be performed at intervals as generally defined in paragraph (j)(1)(ii)( b ) of this section, depending upon its activity, severity of service, and environment, or as specifically indicated below. These inspections shall include the requirements of paragraph (j)(2) of this section and in addition, the following items. Any deficiencies such as listed shall be carefully examined and determination made as to whether they constitute a safety hazard:
Test loads shall not be more than 125 percent of the rated load unless otherwise recommended by the manufacturer. The test reports shall be placed on file where readily available to appointed personnel.
A preventive maintenance program based on the crane manufacturer's recommendations shall be established.
A thorough inspection of all ropes shall be made at least once a month and a certification record which includes the date of inspection, the signature of the person who performed the inspection and an identifier for the ropes which were inspected shall be kept on file where readily available to appointed personnel. Any deterioration, resulting in appreciable loss of original strength, shall be carefully observed and determination made as to whether further use of the rope would constitute a safety hazard. Some of the conditions that could result in an appreciable loss of strength are the following:
All rope which has been idle for a period of a month or more due to shutdown or storage of a crane on which it is installed shall be given a thorough inspection before it is used. This inspection shall be for all types of deterioration and shall be performed by an appointed person whose approval shall be required for further use of the rope. A certification record shall be available for inspection which includes the date of inspection, the signature of the person who performed the inspection and an identifier for the rope which was inspected.
The crane shall not be loaded beyond its rated load except for test purposes as provided in paragraph (k) of this section.
The employer shall insure that operators are familiar with the operation and care of fire extinguishers provided.
[39 FR 23502, June 27, 1974, as amended at 40 FR 27400, June 27, 1975; 49 FR 5322, Feb. 10, 1984; 51 FR 34560, Sept. 29, 1986; 55 FR 32015, Aug. 6, 1990; 61 FR 9239, Mar. 7, 1996; 81 FR 83005, Nov. 18, 2016]
means the American National Standards Institute.
This section applies to crawler cranes, locomotive cranes, wheel mounted cranes of both truck and self-propelled wheel type, and any variations thereof which retain the same fundamental characteristics. This section includes only cranes of the above types, which are basically powered by internal combustion engines or electric motors and which utilize drums and ropes. Cranes designed for railway and automobile wreck clearances are excepted. The requirements of this section are applicable only to machines when used as lifting cranes.
All new crawler, locomotive, and truck cranes constructed and utilized on or after August 31, 1971, shall meet the design specifications of the American National Standard Safety Code for Crawler, Locomotive, and Truck Cranes, ANSI B30.5-1968, which is incorporated by reference as specified in § 1910.6. Crawler, locomotive, and truck cranes constructed prior to August 31, 1971, should be modified to conform to those design specifications by February 15, 1972, unless it can be shown that the crane cannot feasibly or economically be altered and that the crane substantially complies with the requirements of this section.
Only designated personnel shall be permitted to operate a crane covered by this section.
where stability governs lifting performance.
| Type of crane mounting | Maximum load ratings (percent of tipping loads) |
|---|---|
| Locomotive, without outriggers: | |
| Booms 60 feet or less | 1 85 |
| Booms over 60 feet | 1 85 |
| Locomotive, using outriggers fully extended | 80 |
| Crawler, without outriggers | 75 |
| Crawler, using outriggers fully extended | 85 |
| Truck and wheel mounted without outriggers or using outriggers fully extended | 85 |
| 1 Unless this results in less than 30,000 pound-feet net stabilizing moment about the rail, which shall be minimum with such booms. |
A substantial and durable rating chart with clearly legible letters and figures shall be provided with each crane and securely fixed to the crane cab in a location easily visible to the operator while seated at his control station.
Prior to initial use all new and altered cranes shall be inspected to insure compliance with provisions of this section.
Inspection procedure for cranes in regular service is divided into two general classifications based upon the intervals at which inspection should be performed. The intervals in turn are dependent upon the nature of the critical components of the crane and the degree of their exposure to wear, deterioration, or malfunction. The two general classifications are herein designated as “frequent” and “periodic”, with respective intervals between inspections as defined below:
Daily to monthly intervals.
1- to 12-month intervals, or as specifically recommended by the manufacturer.
Items such as the following shall be inspected for defects at intervals as defined in paragraph (d)(2)(i) of this section or as specifically indicated including observation during operation for any defects which might appear between regular inspections. Any deficiencies such as listed shall be carefully examined and determination made as to whether they constitute a safety hazard:
Daily.
For hooks with cracks or having more than 15 percent in excess of normal throat opening or more than 10° twist from the plane of the unbent hook.
Complete inspections of the crane shall be performed at intervals as generally defined in paragraph (d)(2)(ii) of this section depending upon its activity, severity of service, and environment, or as specifically indicated below. These inspections shall include the requirements of paragraph (d)(3) of this section and in addition, items such as the following. Any deficiencies such as listed shall be carefully examined and determination made as to whether they constitute a safety hazard:
Certification records which include the date of inspection, the signature of the person who performed the inspection and the serial number, or other identifier, of the crane which was inspected shall be made monthly on critical items in use such as brakes, crane hooks, and ropes. This certification record shall be kept readily available.
After adjustments and repairs have been made the crane shall not be operated until all guards have been reinstalled, safety devices reactivated, and maintenance equipment removed.
A thorough inspection of all ropes in use shall be made at least once a month and a certification record which includes the date of inspection, the signature of the person who performed the inspection and an identifier for the ropes shall be prepared and kept on file where readily available. All inspections shall be performed by an appointed or authorized person. Any deterioration, resulting in appreciable loss of original strength shall be carefully observed and detemination made as to whether further use of the rope would constitute a safety hazard. Some of the conditions that could result in an appreciable loss of strength are the following:
Rail clamps shall not be used as a means of restraining tipping of a locomotive crane.
Cranes shall not be operated without the full amount of any ballast or counterweight in place as specified by the maker, but truck cranes that have dropped the ballast or counterweight may be operated temporarily with special care and only for light loads without full ballast or counterweight in place. The ballast or counterweight in place specified by the manufacturer shall not be exceeded.
A locomotive crane shall not be swung into a position where railway cars on an adjacent track might strike it, until it has been ascertained that cars are not being moved on the adjacent track and proper flag protection has been established.
For operations near overhead electric lines, see § 1910.333(c)(3).
[39 FR 23502, June 27, 1974, as amended at 49 FR 5323, Feb. 10, 1984; 51 FR 34561, Sept. 29, 1986; 53 FR 12122, Apr. 12, 1988; 55 FR 32015, Aug. 6, 1990; 61 FR 9239, Mar. 7, 1996]
means the American National Standards Institute.
This section applies to guy, stiffleg, basket, breast, gin pole, Chicago boom and A-frame derricks of the stationary type, capable of handling loads at variable reaches and powered by hoists through systems of rope reeving, used to perform lifting hook work, single or multiple line bucket work, grab, grapple, and magnet work. Derricks may be permanently installed for temporary use as in construction work. The requirements of this section also apply to any modification of these types which retain their fundamental features, except for floating derricks.
All new derricks constructed and installed on or after August 31, 1971, shall meet the design specifications of the American National Standard Safety Code for Derricks, ANSI B30.6-1969, which is incorporated by reference as specified in § 1910.6.
Only designated personnel shall be permitted to operate a derrick covered by this section.
For permanently installed derricks with fixed lengths of boom, guy, and mast, a substantial, durable, and clearly legible rating chart shall be provided with each derrick and securely affixed where it is visible to personnel responsible for the safe operation of the equipment. The chart shall include the following data:
Size and construction of rope may be shown either on the rating chart or in the operating manual.
For nonpermanent installations, the manufacturer shall provide sufficient information from which capacity charts can be prepared for the particular installation. The capacity charts shall be located at the derricks or the jobsite office.
Items such as the following shall be inspected for defects at intervals as defined in paragraph (d)(1)(ii)( a ) of this section or as specifically indicated, including observation during operation for any defects which might appear between regular inspections. Deficiencies shall be carefully examined for any safety hazard:
Inspect daily for adjustment, wear, and lubrication.
Inspect daily, visually.
Daily.
Daily.
Prior to initial use all new and altered derricks shall be tested to insure compliance with this section including the following functions:
All anchorages shall be approved by the appointed person. Rock and hairpin anchorages may require special testing.
A preventive maintenance program based on the derrick manufacturer's recommendations shall be established.
A thorough inspection of all ropes in use shall be made at least once a month and a certification record which includes the date of inspection, the signature of the person who performed the inspection, and an identifier for the ropes which were inspected shall be prepared and kept on file where readily available. Any deterioration, resulting in appreciable loss of original strength shall be carefully observed and determination made as to whether further use of the rope would constitute a safety hazard. Some of the conditions that could result in an appreciable loss of strength are the following:
Heavy wear and/or broken wires may occur in sections in contact with equalizer sheaves or other sheaves where rope travel is limited, or with saddles. Particular care shall be taken to inspect ropes at these locations.
All rope which has been idle for a period of a month or more due to shutdown or storage of a derrick on which it is installed shall be given a thorough inspection before it is used. This inspection shall be for all types of deterioration. A certification record shall be prepared and kept readily available which includes the date of inspection, the signature of the person who performed the inspection, and an identifier for the ropes which were inspected.
Particular care shall be taken in the inspection of nonrotating rope.
Derrick operations shall be directed only by the individual specifically designated for that purpose.
Dogs, pawls, or other positive holding mechanism on the hoist shall be engaged. When not in use, the derrick boom shall:
For operations near overhead electric lines, see § 1910.333(c)(3).
[37 FR 22102, Oct. 18, 1972, as amended at 38 FR 14373, June 1, 1973; 43 FR 49750, Oct. 24, 1978; 49 FR 5323, Feb. 10, 1984; 51 FR 34561, Sept. 29, 1986; 53 FR 12122, Apr. 12, 1988; 55 FR 32015, Aug. 6, 1990; 61 FR 9240, Mar. 7, 1996]
Prior to each day's operation a briefing shall be conducted. This briefing shall set forth the plan of operation for the pilot and ground personnel.
Loads shall be properly slung. Tag lines shall be of a length that will not permit their being drawn up into the rotors. Pressed sleeve, swedged eyes, or equivalent means shall be used for all freely suspended loads to prevent hand splices from spinning open or cable clamps from loosening.
All electrically operated cargo hooks shall have the electrical activating device so designed and installed as to prevent inadvertent operation. In addition, these cargo hooks shall be equipped with an emergency mechanical control for releasing the load. The employer shall ensure that the hooks are tested prior to each day's operation by a competent person to determine that the release functions properly, both electrically and mechanically.
The employer shall take all necessary precautions to protect employees from flying objects in the rotor downwash. All loose gear within 100 feet of the place of lifting the load or depositing the load, or within all other areas susceptible to rotor downwash, shall be secured or removed.
Good housekeeping shall be maintained in all helicopter loading and unloading areas.
The size and weight of loads, and the manner in which loads are connected to the helicopter shall be checked. A lift may not be made if the helicopter operator believes the lift cannot be made safely.
When employees perform work under hovering craft, a safe means of access shall be provided for employees to reach the hoist line hook and engage or disengage cargo slings. Employees may not be permitted to perform work under hovering craft except when necessary to hook or unhook loads.
Static charge on the suspended load shall be dissipated with a grounding device before ground personnel touch the suspended load, unless protective rubber gloves are being worn by all ground personnel who may be required to touch the suspended load.
The weight of an external load shall not exceed the helicopter manufacturer's rating.
Hoist wires or other gear, except for pulling lines or conductors that are allowed to “pay out” from a container or roll off a reel, shall not be attached to any fixed ground structure, or allowed to foul on any fixed structure.
Ground personnel shall be instructed and the employer shall ensure that when visibility is reduced by dust or other conditions, they shall exercise special caution to keep clear of main and stabilizing rotors. Precautions shall also be taken by the employer to eliminate, as far as practical, the dust or other conditions reducing the visibility.
The employer shall instruct the aircrew and ground personnel on the signal systems to be used and shall review the system with the employees in advance of hoisting the load. This applies to both radio and hand signal systems. Hand signals, where used, shall be as shown in Figure N-1.
No employee shall be permitted to approach within 50 feet of the helicopter when the rotor blades are turning, unless his work duties require his presence in that area.
The employer shall instruct employees, and shall ensure, that whenever approaching or leaving a helicopter which has its blades rotating, all employees shall remain in full view of the pilot and keep in a crouched position. No employee shall be permitted to work in the area from the cockpit or cabin rearward while blades are rotating, unless authorized by the helicopter operator to work there.
Sufficient ground personnel shall be provided to ensure that helicopter loading and unloading operations can be performed safely.
There shall be constant reliable communication between the pilot and a designated employee of the ground crew who acts as a signalman during the period of loading and unloading. The signalman shall be clearly distinguishable from other ground personnel.
This section applies to slings used in conjunction with other material handling equipment for the movement of material by hoisting, in employments covered by this part. The types of slings covered are those made from alloy steel chain, wire rope, metal mesh, natural or synthetic fiber rope (conventional three strand construction), and synthetic web (nylon, polyester, and polypropylene).
Angle of loading is the inclination of a leg or branch of a sling measured from the horizontal or vertical plane as shown in Fig. N-184-5; provided that an angle of loading of five degrees or less from the vertical may be considered a vertical angle of loading.
Basket hitch is a sling configuration whereby the sling is passed under the load and has both ends, end attachments, eyes or handles on the hook or a single master link.
Braided wire rope is a wire rope formed by plaiting component wire ropes.
Bridle wire rope sling is a sling composed of multiple wire rope legs with the top ends gathered in a fitting that goes over the lifting hook.
Cable laid endless sling-mechanical joint is a wire rope sling made endless by joining the ends of a single length of cable laid rope with one or more metallic fittings.
Cable laid grommet-hand tucked is an endless wire rope sling made from one length of rope wrapped six times around a core formed by hand tucking the ends of the rope inside the six wraps.
Cable laid rope is a wire rope composed of six wire ropes wrapped around a fiber or wire rope core.
Cable laid rope sling-mechanical joint is a wire rope sling made from a cable laid rope with eyes fabricated by pressing or swaging one or more metal sleeves over the rope junction.
Choker hitch is a sling configuration with one end of the sling passing under the load and through an end attachment, handle or eye on the other end of the sling.
Coating is an elastomer or other suitable material applied to a sling or to a sling component to impart desirable properties.
Cross rod is a wire used to join spirals of metal mesh to form a complete fabric. (See Fig. N-184-2.)
Designated means selected or assigned by the employer or the employer's representative as being qualified to perform specific duties.
Equivalent entity is a person or organization (including an employer) which, by possession of equipment, technical knowledge and skills, can perform with equal competence the same repairs and tests as the person or organization with which it is equated.
Fabric (metal mesh) is the flexible portion of a metal mesh sling consisting of a series of transverse coils and cross rods.
Female handle (choker) is a handle with a handle eye and a slot of such dimension as to permit passage of a male handle thereby allowing the use of a metal mesh sling in a choker hitch. (See Fig. N-184-1.)
Handle is a terminal fitting to which metal mesh fabric is attached. (See Fig. N-184-1.)
Handle eye is an opening in a handle of a metal mesh sling shaped to accept a hook, shackle or other lifting device. (See Fig. N-184-1.)
Hitch is a sling configuration whereby the sling is fastened to an object or load, either directly to it or around it.
Link is a single ring of a chain.
Male handle (triangle) is a handle with a handle eye.
Master coupling link is an alloy steel welded coupling link used as an intermediate link to join alloy steel chain to master links. (See Fig. N-184-3.)
Master link or gathering ring is a forged or welded steel link used to support all members (legs) of an alloy steel chain sling or wire rope sling. (See Fig. N-184-3.)
Mechanical coupling link is a nonwelded, mechanically closed steel link used to attach master links, hooks, etc., to alloy steel chain.
Proof test is a nondestructive tension test performed by the sling manufacturer or an equivalent entity to verify construction and workmanship of a sling.
Rated capacity or working load limit is the maximum working load permitted by the provisions of this section.
Reach is the effective length of an alloy steel chain sling measured from the top bearing surface of the upper terminal component to the bottom bearing surface of the lower terminal component.
Selvage edge is the finished edge of synthetic webbing designed to prevent unraveling.
Sling is an assembly which connects the load to the material handling equipment.
Sling manufacturer is a person or organization that assembles sling components into their final form for sale to users.
Spiral is a single transverse coil that is the basic element from which metal mesh is fabricated. (See Fig. N-184-2.)
Strand laid endless sling-mechanical joint is a wire rope sling made endless from one length of rope with the ends joined by one or more metallic fittings.
Strand laid grommet-hand tucked is an endless wire rope sling made from one length of strand wrapped six times around a core formed by hand tucking the ends of the strand inside the six wraps.
Strand laid rope is a wire rope made with strands (usually six or eight) wrapped around a fiber core, wire strand core, or independent wire rope core (IWRC).
Vertical hitch is a method of supporting a load by a single, vertical part or leg of the sling. (See Fig. N-184-4.)
Whenever any sling is used, the following practices shall be observed:
Each day before being used, the sling and all fastenings and attachments shall be inspected for damage or defects by a competent person designated by the employer. Additional inspections shall be performed during sling use, where service conditions warrant. Damaged or defective slings shall be immediately removed from service.
Alloy steel chain slings shall have permanently affixed durable identification stating size, grade, rated capacity, and reach.
The employer shall ensure that before use, each new, repaired, or reconditioned alloy steel chain sling, including all welded components in the sling assembly, shall be proof tested by the sling manufacturer or equivalent entity, in accordance with paragraph 5.2 of the American Society of Testing and Materials Specification A391-65, which is incorporated by reference as specified in § 1910.6 (ANSI G61.1-1968). The employer shall retain a certificate of the proof test and shall make it available for examination.
Employers must permanently remove an alloy steel-chain slings from service if it is heated above 1000 degrees F. When exposed to service temperatures in excess of 600 degrees F, employers must reduce the maximum working-load limits permitted by the chain manufacturer in accordance with the chain or sling manufacturer's recommendations.
If the chain size at any point of the link is less than that stated in Table N-184-1, the employer must remove the chain from service.
| Chain size, inches | Minimum allowable chain size, inches |
|---|---|
| 1 ⁄ 4 | 13 ⁄ 64 |
| 3 ⁄ 8 | 19 ⁄ 64 |
| 1 ⁄ 2 | 25 ⁄ 64 |
| 5 ⁄ 8 | 31 ⁄ 64 |
| 3 ⁄ 4 | 19 ⁄ 32 |
| 7 ⁄ 8 | 4 5 ⁄ 64 |
| 1 | 13 ⁄ 16 |
| 1 1 ⁄ 8 | 29 ⁄ 32 |
| 1 1 ⁄ 4 | 1 |
| 1 3 ⁄ 8 | 1 3 ⁄ 32 |
| 1 1 ⁄ 2 | 1 3 ⁄ 16 |
| 1 3 ⁄ 4 | 1 13 ⁄ 32 |
Employers must use only wire-rope slings that have permanently affixed and legible identification markings as prescribed by the manufacturer, and that indicate the recommended safe working load for the type(s) of hitch(es) used, the angle upon which it is based, and the number of legs if more than one.
Fiber core wire rope slings of all grades shall be permanently removed from service if they are exposed to temperatures in excess of 200 °F. When nonfiber core wire rope slings of any grade are used at temperatures above 400 °F or below minus 60 °F, recommendations of the sling manufacturer regarding use at that temperature shall be followed.
Wire rope slings shall be immediately removed from service if any of the following conditions are present:
Each metal mesh sling shall have permanently affixed to it a durable marking that states the rated capacity for vertical basket hitch and choker hitch loadings.
Handles shall have a rated capacity at least equal to the metal fabric and exhibit no deformation after proof testing.
The fabric and handles shall be joined so that:
Coatings which diminish the rated capacity of a sling shall not be applied.
All new and repaired metal mesh slings, including handles, shall not be used unless proof tested by the manufacturer or equivalent entity at a minimum of 1 1/2 times their rated capacity. Elastomer impregnated slings shall be proof tested before coating.
Metal mesh slings which are not impregnated with elastomers may be used in a temperature range from minus 20 °F to plus 550 °F without decreasing the working load limit. Metal mesh slings impregnated with polyvinyl chloride or neoprene may be used only in a temperature range from zero degrees to plus 200 °F. For operations outside these temperature ranges or for metal mesh slings impregnated with other materials, the sling manufacturer's recommendations shall be followed.
Metal mesh slings shall be immediately removed from service if any of the following conditions are present:
percent reduction of the original cross sectional area of metal at any point around the handle eye.
Employers must use natural and synthetic fiber-rope slings that have permanently affixed and legible identification markings stating the rated capacity for the type(s) of hitch(es) used and the angle upon which it is based, type of fiber material, and the number of legs if more than one.
Natural and synthetic fiber rope slings, except for wet frozen slings, may be used in a temperature range from minus 20 °F to plus 180 °F without decreasing the working load limit. For operations outside this temperature range and for wet frozen slings, the sling manufacturer's recommendations shall be followed.
Spliced fiber rope slings shall not be used unless they have been spliced in accordance with the following minimum requirements and in accordance with any additional recommendations of the manufacturer:
Fiber rope slings shall not be used if end attachments in contact with the rope have sharp edges or projections.
Natural and synthetic fiber rope slings shall be immediately removed from service if any of the following conditions are present:
Only fiber rope slings made from new rope shall be used. Use of repaired or reconditioned fiber rope slings is prohibited.
Each sling shall be marked or coded to show the rated capacities for each type of hitch and type of synthetic web material.
Synthetic webbing shall be of uniform thickness and width and selvage edges shall not be split from the webbing's width.
Fittings shall be:
When synthetic web slings are used, the following precautions shall be taken:
Synthetic web slings of polyester and nylon shall not be used at temperatures in excess of 180 °F. Polypropylene web slings shall not be used at temperatures in excess of 200 °F.
Synthetic web slings shall be immediately removed from service if any of the following conditions are present:
[40 FR 27369, June 27, 1975, as amended at 40 FR 31598, July 28, 1975; 41 FR 13353, Mar. 30, 1976; 58 FR 35309, June 30, 1993; 61 FR 9240, Mar. 7, 1996; 76 FR 33607, June 8, 2011; 84 FR 15105, Apr. 15, 2019]
Limitation: Hole dimension (H) should not be greater than two-thirds of wheel diameter dimension (D) for precision, cylindrical, centerless, or surface grinding applications. Maximum hole size for all other applications should not exceed one-half wheel diameter.
Type 1—Straight Wheel
Peripheral grinding wheel having a diameter, thickness and hole.
Limitation: Rim height, T dimension, is generally equal to or greater than rim thickness, W dimension.
Type 2—Cylinder Wheel
Side grinding wheel having a diameter, thickness and wall—wheel is mounted on the diameter.
Limitation: Minimum back thickness, E dimension, should not be less than one-fourth T dimension. In addition, when unthreaded hole wheels are specified, the inside flat, K dimension, must be large enough to accommodate a suitable flange.
Type 6—Straight-cup Wheel
Side grinding wheel having a diameter, thickness and hole with one side straight or flat and the opposite side recessed. This type, however, differs from Type 5 in that the grinding is performed on the wall of the abrasive created by the difference between the diameter of the recess and the outside diameter of the wheel. Therefore, the wall dimension “W” takes precedence over the diameter of the recess as an essential intermediate dimension to describe this shape type.
Limitation: Minimum back thickness, E dimension, should not be less than one-fourth T dimension. In addition when unthreaded hole wheels are specified the inside flat, K dimension, shall be large enough to accommodate a suitable flange.
Type 11—Flaring-cup Wheel
Side grinding wheel having a wall flared or tapered outward from the back. Wall thickness at the back is normally greater than at the grinding face (W).
Limitation: These wheels shall be mounted only with a special tapered flange.
Typical examples of modified types 6 and 11 wheels (terrazzo) showing tapered K dimensions.
Special supporting, back adapter and inside flange nuts are required for the proper mounting of these types of wheels subject to limitations of § 1910.215(c)(4) (i) and (ii).
Limitations: See § 1910.215(c)(1).
Surface Feet Per Minute = 3.1416 × diameter in inches × r.p.m. ÷ 12 or.262 × diameter in inches × r.p.m.
Examples:
Cutting off wheels are recommended only for use on specially designed and fully guarded machines and are subject to the following maximum thickness and hole size limitations.
| Wheel diameter | Max. thickness (inch) |
|---|---|
| 6 inch and smaller | 3 ⁄ 18 |
| Larger than 6 inches to 12 inches | 1 ⁄ 4 |
| Larger than 12 inches to 23 inches | 3 ⁄ 8 |
| Larger than 23 inches | 1 ⁄ 2 |
[39 FR 23502, June 27, 1974, as amended at 39 FR 41846, Dec. 3, 1974; 53 FR 8353, Mar. 14, 1988]
One or more methods of machine guarding shall be provided to protect the operator and other employees in the machine area from hazards such as those created by point of operation, ingoing nip points, rotating parts, flying chips and sparks. Examples of guarding methods are—barrier guards, two-hand tripping devices, electronic safety devices, etc.
Guards shall be affixed to the machine where possible and secured elsewhere if for any reason attachment to the machine is not possible. The guard shall be such that it does not offer an accident hazard in itself.
When the periphery of the blades of a fan is less than seven (7) feet above the floor or working level, the blades shall be guarded. The guard shall have openings no larger than one-half ( 1/2 ) inch.
Machines designed for a fixed location shall be securely anchored to prevent walking or moving.
The requirements of this paragraph are also applicable to sliding cutoff saws mounted above the table.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49750, Oct. 24, 1978; 49 FR 5323, Feb. 10, 1984]
Abrasive wheels shall be used only on machines provided with safety guards as defined in the following paragraphs of this section, except:
The safety guard shall cover the spindle end, nut, and flange projections. The safety guard shall be mounted so as to maintain proper alignment with the wheel, and the strength of the fastenings shall exceed the strength of the guard, except:
Grinding machines shall be equipped with flanges in accordance with paragraph (c) of this section.
On offhand grinding machines, work rests shall be used to support the work. They shall be of rigid construction and designed to be adjustable to compensate for wheel wear. Work rests shall be kept adjusted closely to the wheel with a maximum opening of one-eighth inch to prevent the work from being jammed between the wheel and the rest, which may cause wheel breakage. The work rest shall be securely clamped after each adjustment. The adjustment shall not be made with the wheel in motion.
Natural sandstone wheels and metal, wooden, cloth, or paper discs, having a layer of abrasive on the surface are not covered by this section.
Cup wheels (Types 6 and 11) shall be protected by:
The maximum exposure angles specified in paragraphs (b) (3) through (8) of this section shall not be exceeded. Visors or other accessory equipment shall not be included as a part of the guard when measuring the guard opening, unless such equipment has strength equal to that of the guard.
The angular exposure of the grinding wheel periphery and sides for safety guards used on machines known as bench and floor stands should not exceed 90° or one-fourth of the periphery. This exposure shall begin at a point not more than 65° above the horizontal plane of the wheel spindle. (See Figures O-6 and O-7 and paragraph (b)(9) of this section.)
Wherever the nature of the work requires contact with the wheel below the horizontal plane of the spindle, the exposure shall not exceed 125°. (See Figures O-8 and O-9.)
The maximum angular exposure of the grinding wheel periphery and sides for safety guards used on cylindrical grinding machines shall not exceed 180°. This exposure shall begin at a point not more than 65° above the horizontal plane of the wheel spindle. (See Figures O-10 and O-11 and subparagraph (9) of this paragraph.)
The maximum angular exposure of the grinding wheel periphery and sides for safety guards used on cutting-off machines and on surface grinding machines which employ the wheel periphery shall not exceed 150°. This exposure shall begin at a point not less than 15° below the horizontal plane of the wheel spindle. (See Figures O-12 and O-13)
The maximum angular exposure of the grinding wheel periphery and sides for safety guards used on grinders known as automatic snagging machines shall not exceed 180° and the top half of the wheel shall be enclosed at all times. (See Figures O-14 and O-15.)
Safety guards of the types described in subparagraphs (3) and (4) of this paragraph, where the operator stands in front of the opening, shall be constructed so that the peripheral protecting member can be adjusted to the constantly decreasing diameter of the wheel. The maximum angular exposure above the horizontal plane of the wheel spindle as specified in paragraphs (b) (3) and (4) of this section shall never be exceeded, and the distance between the wheel periphery and the adjustable tongue or the end of the peripheral member at the top shall never exceed one-fourth inch. (See Figures O-18, O-19, O-20, O-21, O-22, and O-23.)
correct
Showing adjustable tongue giving required angular protection for all sizes of wheel used.
correct
Showing movable guard with opening small enough to give required protection for smallest size wheel used.
incorrect
Showing movable guard with size of opening correct for full size wheel but too large for smaller wheels.
Band type guards shall conform to the following general specifications:
Abrasive wheel machinery guards shall meet the design specifications of the American National Standard Safety Code for the Use, Care, and Protection of Abrasive Wheels, ANSI B7.1-1970, which is incorporated by reference as specified in § 1910.6. This requirement shall not apply to natural sandstone wheels or metal, wooden, cloth, or paper discs, having a layer of abrasive on the surface.
All abrasive wheels shall be mounted between flanges which shall not be less than one-third the diameter of the wheel.
The Type 27 A Wheel is mounted between flat non-relieved flanges of equal bearing surfaces.
Flanges shall be dimensionally accurate and in good balance. There shall be no rough surfaces or sharp edges.
Types 27 and 28 wheels, because of their shape, require specially designed adaptors.
The driving flange shall be securely fastened to the spindle and the bearing surface shall run true. When more than one wheel is mounted between a single set of flanges, wheels may be cemented together or separated by specially designed spacers. Spacers shall be equal in diameter to the mounting flanges and have equal bearing surfaces. (See paragraph (d)(6) of this section.)
All flanges shall be maintained in good condition. When the bearing surfaces become worn, warped, sprung, or damaged they should be trued or refaced. When refacing or truing, care shall be exercised to make sure that proper relief and rigidity is maintained as specified in paragraphs (c) (2) and (5) of this section and they shall be replaced when they do not conform to these subparagraphs and Table O-4, Figure O-30, Table O-5, Figure O-31, Table O-6, Figure O-32, and Table O-8, Figure O-35. Failure to observe these rules might cause excessive flange pressure around the hole of the wheel. This is especially true of wheel-sleeve or adaptor flanges.
Immediately before mounting, all wheels shall be closely inspected and sounded by the user (ring test) to make sure they have not been damaged in transit, storage, or otherwise. The spindle speed of the machine shall be checked before mounting of the wheel to be certain that it does not exceed the maximum operating speed marked on the wheel. Wheels should be tapped gently with a light nonmetallic implement, such as the handle of a screwdriver for light wheels, or a wooden mallet for heavier wheels. If they sound cracked (dead), they shall not be used. This is known as the “Ring Test”.
Grinding wheels shall fit freely on the spindle and remain free under all grinding conditions. A controlled clearance between the wheel hole and the machine spindle (or wheel sleeves or adaptors) is essential to avoid excessive pressure from mounting and spindle expansion. To accomplish this, the machine spindle shall be made to nominal (standard) size plus zero minus.002 inch, and the wheel hole shall be made suitably oversize to assure safety clearance under the conditions of operating heat and pressure.
All contact surfaces of wheels, blotters and flanges shall be flat and free of foreign matter.
When a bushing is used in the wheel hole it shall not exceed the width of the wheel and shall not contact the flanges.
When blotters or flange facings of compressible material are required, they shall cover entire contact area of wheel flanges. Blotters need not be used with the following types of wheels:
When more than one wheel is mounted between a single set of flanges, wheels may be cemented together or separated by specially designed spacers. Spacers shall be equal in diameter to the mounting flanges and have equal bearing surfaces. When mounting wheels which have not been cemented together, or ones which do not utilize separating spacers, care must be exercised to use wheels specially manufactured for that purpose.
| Material used in construction of guard | Maximum thickness of cutting off wheel | Speed not to exceed | Cutting off wheel diameters | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 6 to 11 inches | Over 11 to 20 inches | Over 20 to 30 inches | Over 30 to 48 inches | Over 48 to 72 inches | ||||||||
| A | B | A | B | A | B | A | B | A | B | |||
| Structural steel (min. tensile strength 60,000 p.s.i.) | 1 ⁄ 2 inch or less | 14,200 SFPM | 1 ⁄ 16 | 1 ⁄ 16 | 3 ⁄ 32 | 3 ⁄ 32 | 1 ⁄ 8 | 1 ⁄ 8 | 3 ⁄ 16 | 3 ⁄ 16 | 1 ⁄ 4 | 1 ⁄ 4 |
| 1 ⁄ 2 inch or less | 16,000 SFPM | 3 ⁄ 32 | 1 ⁄ 8 | 1 ⁄ 8 | 1 ⁄ 8 | 3 ⁄ 16 | 1 ⁄ 8 | 1 ⁄ 4 | 3 ⁄ 16 | 5 ⁄ 16 | 1 ⁄ 4 |
| Minimum material specifications | Diameter of wheel | Minimum thickness of band A | Minimum diameter of rivets | Maximum distance between centers of rivets |
|---|---|---|---|---|
| Inches | ||||
| Hot rolled steel SAE 1008 | Under 8 | 1 ⁄ 16 | 3 ⁄ 16 | 3 ⁄ 4 |
| 8 to 24 | 1 ⁄ 8 | 1 ⁄ 4 | 1 | |
| Over 24 to 30 | 1 ⁄ 4 | 3 ⁄ 8 | 1 1 ⁄ 4 |
| Wheel diameter | Wheel hole diameter | B—Minimum flange diameter | D—Minimun thickness of flange at bore | E—Minimum thickness of flange at edge of undercut | F 1 —(D-E) minimum thickness |
|---|---|---|---|---|---|
| 12 to 14 | 4 | 6 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 |
| 5 | 7 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 | |
| 6 | 8 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 | |
| Larger than 14 to 18 | 4 | 6 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 |
| 5 | 7 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 | |
| 6 | 8 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 | |
| 7 | 9 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 | |
| 8 | 10 | 7 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 | |
| Larger than 18 to 24 | 6 | 8 | 1 | 1 ⁄ 2 | 1 ⁄ 2 |
| 7 | 9 | 1 | 1 ⁄ 2 | 1 ⁄ 2 | |
| 8 | 10 | 1 | 1 ⁄ 2 | 1 ⁄ 2 | |
| 10 | 12 | 1 | 1 ⁄ 2 | 1 ⁄ 2 | |
| 12 | 14 | 1 | 1 ⁄ 2 | 1 ⁄ 2 | |
| Larger than 24 to 30 | 12 | 15 | 1 | 1 ⁄ 2 | 1 ⁄ 2 |
| Larger than 30 to 36 | 12 | 15 | 1 3 ⁄ 8 | 7 ⁄ 8 | 1 ⁄ 2 |
| 1 For wheels under 1 1 ⁄ 4 inches thick F dimension shall not exceed 40 percent of wheel thickness. |
| A—Diameter of wheel | B—Minimum outside diameter of flanges | C—Radial width of bearing surface | D—Minimum thickness of flange at bore | E—Minimum thickness of flange at edge of recess | |
|---|---|---|---|---|---|
| Minimum | Maximum | ||||
| 1 | 3 ⁄ 8 | 1 ⁄ 16 | 1 ⁄ 8 | 1 ⁄ 16 | 1 ⁄ 16 |
| 2 | 3 ⁄ 4 | 1 ⁄ 8 | 3 ⁄ 16 | 1 ⁄ 8 | 3 ⁄ 32 |
| 3 | 1 | 1 ⁄ 8 | 3 ⁄ 16 | 3 ⁄ 16 | 3 ⁄ 32 |
| 4 | 1 3 ⁄ 8 | 1 ⁄ 8 | 3 ⁄ 16 | 3 ⁄ 16 | 1 ⁄ 8 |
| 5 | 1 3 ⁄ 4 | 3 ⁄ 16 | 1 ⁄ 4 | 1 ⁄ 4 | 1 ⁄ 8 |
| 6 | 2 | 1 ⁄ 4 | 1 ⁄ 2 | 3 ⁄ 8 | 3 ⁄ 16 |
| 7 | 2 1 ⁄ 2 | 1 ⁄ 4 | 1 ⁄ 2 | 3 ⁄ 8 | 3 ⁄ 16 |
| 8 | 3 | 1 ⁄ 4 | 1 ⁄ 2 | 3 ⁄ 8 | 3 ⁄ 16 |
| 10 | 3 1 ⁄ 2 | 5 ⁄ 16 | 5 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 4 |
| 12 | 4 | 5 ⁄ 16 | 5 ⁄ 8 | 1 ⁄ 2 | 5 ⁄ 16 |
| 14 | 4 1 ⁄ 2 | 3 ⁄ 8 | 3 ⁄ 4 | 1 ⁄ 2 | 5 ⁄ 16 |
| 16 | 5 1 ⁄ 2 | 1 ⁄ 2 | 1 | 1 ⁄ 2 | 5 ⁄ 16 |
| 18 | 6 | 1 ⁄ 2 | 1 | 5 ⁄ 8 | 3 ⁄ 8 |
| 20 | 7 | 5 ⁄ 8 | 1 1 ⁄ 4 | 5 ⁄ 8 | 3 ⁄ 8 |
| 22 | 7 1 ⁄ 2 | 5 ⁄ 8 | 1 1 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 16 |
| 24 | 8 | 3 ⁄ 4 | 1 1 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 16 |
| 26 | 8 1 ⁄ 2 | 3 ⁄ 4 | 1 1 ⁄ 4 | 5 ⁄ 8 | 1 ⁄ 2 |
| 28 | 10 | 7 ⁄ 8 | 1 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 |
| 30 | 10 | 7 ⁄ 8 | 1 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 |
| 36 | 12 | 1 | 2 | 7 ⁄ 8 | 3 ⁄ 4 |
| 42 | 14 | 1 | 2 | 7 ⁄ 8 | 3 ⁄ 4 |
| 48 | 16 | 1 1 ⁄ 4 | 2 | 1 1 ⁄ 8 | 1 |
| 60 | 20 | 1 1 ⁄ 4 | 2 | 1 1 ⁄ 4 | 1 1 ⁄ 8 |
| 72 | 24 | 1 1 ⁄ 2 | 2 1 ⁄ 2 | 1 3 ⁄ 8 | 1 1 ⁄ 4 |
| 1 Flanges for wheels under 2 inches diameter may be unrelieved and shall be maintained flat and true. |
| Wheel diameter | Wheel hole diameter | B—Minimum flange diameter | D—Minimum thickness of flange at bore | E—Minimum thickness of flange at edge of undercut | F 2 —(D-E) minimum thickness |
|---|---|---|---|---|---|
| 20 | 6 | 8 | 1 | 1 ⁄ 2 | 1 ⁄ 2 |
| 20 | 8 | 10 | 1 1 ⁄ 2 | 3 ⁄ 4 | 3 ⁄ 4 |
| 24 | 12 | 15 | 2 | 1 | 1 |
| 30 | 12 | 15 | 2 | 1 | 1 |
| 36 | 12 | 15 | 2 | 1 | |
| 1 Flanges shall be of steel, quality SAE 1040 or equivalent, annealed plate, heat treated to R. 25-30. | |||||
| 2 For wheels under 1 1 ⁄ 4 inch thick F dimension shall not exceed 40 percent of wheel thickness. |
| Wheel diameter | Wheel hole diameter | B—Minimum outside diameter of flange | D—Minimum thickness of flange at bore | E—Minimum thickness of flange at edge of undercut |
|---|---|---|---|---|
| 12 to 14 | 5 | 7 | 1 ⁄ 2 | 7 ⁄ 16 |
| Larger than 14 to 20 | 5 | 7 | 5 ⁄ 8 | 7 ⁄ 16 |
| 6 | 8 | 5 ⁄ 8 | 7 ⁄ 16 | |
| 8 | 10 | 5 ⁄ 8 | 7 ⁄ 16 | |
| 10 | 11 1 ⁄ 2 | 5 ⁄ 8 | 7 ⁄ 16 | |
| 12 | 13 1 ⁄ 2 | 5 ⁄ 8 | 7 ⁄ 16 | |
| Larger than 20 to 30 | 8 | 10 | 3 ⁄ 4 | 1 ⁄ 2 |
| 10 | 11 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 | |
| 12 | 13 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 | |
| 16 | 17 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 | |
| Larger than 30 to 42 | 12 | 13 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 |
| 16 | 17 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 | |
| 18 | 19 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 | |
| 20 | 21 1 ⁄ 2 | 3 ⁄ 4 | 1 ⁄ 2 | |
| Larger than 42 to 60 | 16 | 20 | 1 | 3 ⁄ 4 |
| 20 | 24 | 1 | 3 ⁄ 4 | |
| 24 | 29 | 1 1 ⁄ 8 | 7 ⁄ 8 | |
| Note: These flanges may be clamped together by means of a central nut, or by a series of bolts or some other equivalent means of fastening. For hole sizes smaller than shown in this table, use table 12. |
| Material used in construction of guard | Maximum thickness of grinding wheel | Grinding wheel diameters | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 3 to 6 inches | Over 6 to 12 inches | Over 12 to 16 inches | Over 16 to 20 inches | Over 20 to 24 inches | Over 24 to 30 inches | Over 30 to 48 inches | |||||||||
| A | B | A | B | A | B | A | B | A | B | A | B | A | B | ||
| Material | 2 | 1 ⁄ 4 | 1 ⁄ 4 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 3 ⁄ 8 | 5 ⁄ 8 | 1 ⁄ 2 | 7 ⁄ 8 | 5 ⁄ 8 | 1 | 3 ⁄ 4 | 1 1 ⁄ 4 | 1 |
| satis- | 4 | 5 ⁄ 16 | 5 ⁄ 16 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 3 ⁄ 8 | 3 ⁄ 4 | 5 ⁄ 8 | 1 | 5 ⁄ 8 | 1 1 ⁄ 8 | 3 ⁄ 4 | 1 3 ⁄ 8 | 1 |
| factory 1 | 6 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 7 ⁄ 16 | 5 ⁄ 8 | 1 ⁄ 2 | 1 | 5 ⁄ 8 | 1 1 ⁄ 8 | 3 ⁄ 4 | 1 1 ⁄ 4 | 7 ⁄ 8 | 1 1 ⁄ 2 | 1 1 ⁄ 8 |
| for | 8 | 5 ⁄ 8 | 9 ⁄ 16 | 7 ⁄ 8 | 3 ⁄ 4 | 1 | 3 ⁄ 4 | 1 1 ⁄ 8 | 3 ⁄ 4 | 1 1 ⁄ 4 | 7 ⁄ 8 | 1 1 ⁄ 2 | 1 1 ⁄ 8 | ||
| speeds | 10 | 3 ⁄ 4 | 11 ⁄ 16 | 7 ⁄ 8 | 3 ⁄ 4 | 1 | 3 ⁄ 4 | 1 1 ⁄ 8 | 3 ⁄ 4 | 1 1 ⁄ 4 | 7 ⁄ 8 | 1 1 ⁄ 2 | 1 1 ⁄ 8 | ||
| up to | 16 | 1 1 ⁄ 8 | 1 | 1 1 ⁄ 4 | 1 | 1 5 ⁄ 16 | 1 | 1 7 ⁄ 16 | 1 1 ⁄ 16 | 1 3 ⁄ 4 | 1 3 ⁄ 8 | ||||
| 8,000 | 20 | 1 3 ⁄ 8 | 1 1 ⁄ 8 | 1 3 ⁄ 8 | 1 1 ⁄ 8 | 1 1 ⁄ 2 | 1 3 ⁄ 8 | 2 | 1 5 ⁄ 8 | ||||||
| SFPM. | |||||||||||||||
| Cast iron (min. tensile strength 20,000 p.s.i.) Class 20. | |||||||||||||||
| Material | 2 | 1 ⁄ 4 | 1 ⁄ 4 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 3 ⁄ 8 | 5 ⁄ 8 | 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 8 | 3 ⁄ 4 | 1 | 7 ⁄ 8 |
| satis- | 4 | 5 ⁄ 16 | 5 ⁄ 16 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 3 ⁄ 8 | 5 ⁄ 8 | 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 8 | 3 ⁄ 4 | 1 1 ⁄ 8 | 7 ⁄ 8 |
| factory 1 | 6 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 7 ⁄ 16 | 5 ⁄ 8 | 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 8 | 5 ⁄ 8 | 1 | 3 ⁄ 4 | 1 1 ⁄ 4 | 7 ⁄ 8 |
| for | 8 | 1 ⁄ 2 | 7 ⁄ 16 | 5 ⁄ 8 | 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 8 | 5 ⁄ 8 | 1 | 3 ⁄ 4 | 1 1 ⁄ 4 | 7 ⁄ 8 | ||
| speeds | 10 | 1 ⁄ 2 | 7 ⁄ 16 | 5 ⁄ 8 | 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 8 | 5 ⁄ 8 | 1 | 3 ⁄ 4 | 1 1 ⁄ 4 | 7 ⁄ 8 | ||
| up to | 16 | 13 ⁄ 16 | 11 ⁄ 16 | 13 ⁄ 16 | 11 ⁄ 16 | 1 | 3 ⁄ 4 | 1 1 ⁄ 8 | 7 ⁄ 8 | 1 3 ⁄ 8 | 1 | ||||
| 9,000 | 20 | 7 ⁄ 8 | 3 ⁄ 4 | 1 | 3 ⁄ 4 | 1 1 ⁄ 8 | 7 ⁄ 8 | 1 1 ⁄ 2 | 1 1 ⁄ 8 | ||||||
| SFPM. | |||||||||||||||
| Malleable iron (min. tensile strength 50,000 p.s.i.) Grade 32510. | |||||||||||||||
| Materials | 2 | 1 ⁄ 4 | 1 ⁄ 4 | 5 ⁄ 16 | 5 ⁄ 16 | 3 ⁄ 8 | 3 ⁄ 8 | 1 ⁄ 2 | 7 ⁄ 16 | 5 ⁄ 8 | 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 | 7 ⁄ 8 | 3 ⁄ 4 |
| satis- | 4 | 1 ⁄ 4 | 1 ⁄ 4 | 1 ⁄ 2 | 1 ⁄ 2 | 1 ⁄ 2 | 1 ⁄ 2 | 9 ⁄ 16 | 1 ⁄ 2 | 5 ⁄ 8 | 1 ⁄ 2 | 3 ⁄ 4 | 5 ⁄ 8 | 1 | 3 ⁄ 4 |
| factory 1 | 6 | 3 ⁄ 8 | 1 ⁄ 4 | 3 ⁄ 4 | 5 ⁄ 8 | 3 ⁄ 4 | 5 ⁄ 8 | 3 ⁄ 4 | 5 ⁄ 8 | 13 ⁄ 16 | 11 ⁄ 16 | 13 ⁄ 16 | 11 ⁄ 16 | 1 1 ⁄ 8 | 3 ⁄ 4 |
| for | 8 | 7 ⁄ 8 | 3 ⁄ 4 | 7 ⁄ 8 | 3 ⁄ 4 | 7 ⁄ 8 | 3 ⁄ 4 | 7 ⁄ 8 | 3 ⁄ 4 | 15 ⁄ 16 | 13 ⁄ 16 | 1 3 ⁄ 8 | 1 | ||
| speeds | 10 | 1 | 7 ⁄ 8 | 1 | 7 ⁄ 8 | 1 | 7 ⁄ 8 | 1 1 ⁄ 8 | 15 ⁄ 16 | 1 1 ⁄ 8 | 1 | 1 7 ⁄ 16 | 1 1 ⁄ 16 | ||
| up to | 16 | 1 1 ⁄ 4 | 1 1 ⁄ 8 | 1 1 ⁄ 4 | 1 1 ⁄ 8 | 1 1 ⁄ 4 | 1 1 ⁄ 8 | 1 1 ⁄ 4 | 1 1 ⁄ 8 | 1 13 ⁄ 16 | 1 7 ⁄ 16 | ||||
| 16,000 | 20 | 1 3 ⁄ 8 | 1 1 ⁄ 4 | 1 3 ⁄ 8 | 1 1 ⁄ 4 | 1 7 ⁄ 16 | 1 5 ⁄ 16 | 2 1 ⁄ 16 | 1 11 ⁄ 16 | ||||||
| SFPM. | |||||||||||||||
| Steel castings (min. tensile strength 60,000 p.s.i.) Grade V60-30. | |||||||||||||||
| Structural | 2 | 1 ⁄ 8 | 1 ⁄ 16 | 5 ⁄ 16 | 1 ⁄ 4 | 5 ⁄ 16 | 1 ⁄ 4 | 5 ⁄ 16 | 1 ⁄ 4 | 5 ⁄ 16 | 1 ⁄ 4 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 3 ⁄ 8 |
| steel | 4 | 1 ⁄ 8 | 1 ⁄ 16 | 3 ⁄ 8 | 5 ⁄ 16 | 3 ⁄ 8 | 5 ⁄ 16 | 3 ⁄ 8 | 5 ⁄ 16 | 3 ⁄ 8 | 5 ⁄ 16 | 3 ⁄ 8 | 5 ⁄ 16 | 1 ⁄ 2 | 3 ⁄ 8 |
| (min. | 6 | 3 ⁄ 16 | 1 ⁄ 16 | 1 ⁄ 2 | 3 ⁄ 8 | 7 ⁄ 16 | 3 ⁄ 8 | 7 ⁄ 16 | 3 ⁄ 8 | 7 ⁄ 16 | 3 ⁄ 8 | 7 ⁄ 16 | 3 ⁄ 8 | 3 ⁄ 4 | 1 ⁄ 2 |
| tensile | 8 | 1 ⁄ 2 | 3 ⁄ 8 | 9 ⁄ 16 | 7 ⁄ 16 | 9 ⁄ 16 | 7 ⁄ 16 | 9 | |||||||
| strength | 10 | 9 ⁄ 16 | 7 ⁄ 16 | 5 ⁄ 8 | 1 ⁄ 2 | 5 ⁄ 8 | 1 ⁄ 2 | 5 ⁄ 8 | 1 ⁄ 2 | 5 ⁄ 8 | 1 ⁄ 2 | 7 ⁄ 8 | 5 ⁄ 8 | ||
| 60,000 | 16 | 5 ⁄ 8 | 9 ⁄ 16 | 3 ⁄ 4 | 5 ⁄ 8 | 3 ⁄ 4 | 5 ⁄ 8 | 13 ⁄ 16 | 11 ⁄ 16 | 1 1 ⁄ 16 | 13 ⁄ 16 | ||||
| p.s.i.) | 20 | 13 ⁄ 16 | 11 ⁄ 16 | 13 ⁄ 16 | 11 ⁄ 16 | 7 ⁄ 8 | 3 ⁄ 4 | 1 3 ⁄ 16 | 15 ⁄ 16 | ||||||
| 1 The recommendations listed in the above table are guides for the conditions stated. Other material, designs or dimensions affording equal or superior protection are also acceptable. |
| Overall thickness of wheel (T) | Maximum exposure of wheel (C) |
|---|---|
| 1 ⁄ 2 | 1 ⁄ 4 |
| 1 | 1 ⁄ 2 |
| 2 | 3 ⁄ 4 |
| 3 | 1 |
| 4 | 1 1 ⁄ 2 |
| 5 and over | 2 |
| A—Diameter of wheel | B 1 —Minimum outside diameter of flange | T—Minimum thickness of flange |
|---|---|---|
| 1 | 5 ⁄ 8 | 1 ⁄ 8 |
| 2 | 1 | 1 ⁄ 8 |
| 3 | 1 | 3 ⁄ 16 |
| 4 | 1 3 ⁄ 8 | 3 ⁄ 16 |
| 5 | 1 3 ⁄ 4 | 1 ⁄ 4 |
| 6 | 2 | 3 ⁄ 8 |
| 1 Note: Must be large enough to extend beyond the bushing. Where prong anchor or cupback bushing are used, this footnote does not apply. |
[39 FR 23502, June 27, 1974, as amended at 43 FR 49750, Oct. 24, 1978; 49 FR 5323, Feb. 10, 1984; 61 FR 9240, Mar. 7, 1996]
Mechanical and electrical equipment and auxiliaries shall be installed in accordance with this section and subpart S of this part.
All new mill installations shall be installed so that the top of the operating rolls is not less than 50 inches above the level on which the operator stands, irrespective of the size of the mill. This distance shall apply to the actual working level, whether it be at the general floor level, in a pit, or on a platform.
A safety trip control shall be provided in front and in back of each mill. It shall be accessible and shall operate readily on contact. The safety trip control shall be one of the following types or a combination thereof:
Installed at front and back of each mill having a 46-inch roll height or over. These bars shall operate readily by pressure of the mill operator's body.
Installed in the front and in the back of each mill and located within 2 inches of a vertical plane tangent to the front and rear rolls. The top rods shall be not more than 72 inches above the level on which the operator stands. The triprods shall be accessible and shall operate readily whether the rods are pushed or pulled.
Installed in the front and in the back of each mill and located within 2 inches of a vertical plane tangent to the front and rear rolls. The cables shall not be more than 72 inches above the level on which the operator stands. The tripwire cable or wire center cord shall operate readily whether cable or cord is pushed or pulled.
All auxiliary equipment such as mill divider, support bars, spray pipes, feed conveyors, strip knives, etc., shall be located in such a manner as to avoid interference with access to and operation of safety devices.
A safety triprod, cable, or wire center cord shall be provided across each pair of in-running rolls extending the length of the face of the rolls. It shall be readily accessible and operate whether pushed or pulled. The safety tripping devices shall be located within reach of the operator and the bite.
On both sides of the calender and near each end of the face of the roll, there shall be a cable or wire center cord connected to the safety trip. They shall operate readily when pushed or pulled.
Where a mill is so installed that persons cannot normally reach through, over, under, or around to come in contact with the roll bite or be caught between a roll and an adjacent object, then, provided such elements are made a fixed part of a mill, safety control devices listed in paragraph (b) of this section shall not apply.
Where a calender is so installed that persons cannot normally reach through, over, under, or around to come in contact with the roll bite or be caught between a roll and an adjacent object, then, provided such elements are made a fixed part of a calender, safety control devices listed in paragraph (c) of this section shall not apply.
All trip and emergency switches shall not be of the automatically resetting type, but shall require manual resetting.
All measurements on mills and calenders shall be taken with the rolls running empty at maximum operating speed. Stopping distances shall be expressed in inches of surface travel of the roll from the instant the emergency stopping device is actuated.
All mills irrespective of the size of the rolls or their arrangement (individually or group-driven) shall be stopped within a distance, as measured in inches of surface travel, not greater than 1 1/2 percent of the peripheral no-load surface speeds of the respective rolls as determined in feet per minute.
[39 FR 23502, June 27, 1974, as amended at 49 FR 5323, Feb. 10, 1984; 61 FR 9240, Mar. 7, 1996]
It shall be the responsibility of any person reconstructing, or modifying a mechanical power press to do so in accordance with paragraph (b) of this section.
Press brakes, hydraulic and pneumatic power presses, bulldozers, hot bending and hot metal presses, forging presses and hammers, riveting machines and similar types of fastener applicators are excluded from the requirements of this section.
Friction brakes provided for stopping or holding a slide movement shall be inherently self-engaging by requiring power or force from an external source to cause disengagement. Brake capacity shall be sufficient to stop the motion of the slide quickly and capable of holding the slide and its attachments at any point in its travel.
control circuits and solenoid value coils shall be powered by not more than a nominal 120-volt a.c. supply obtained from a transformer with an isolated secondary. Higher voltages that may be necessary for operation of machine or control mechanisms shall be isolated from any control mechanism handled by the operator, but motor starters with integral Start-Stop buttons may utilize line voltage control. All d.c. control circuits shall be powered by not more than a nominal 240-volt d.c. supply isolated from any higher voltages.
Air controlling equipment shall be protected against foreign material and water entering the pneumatic system of the press. A means of air lubrication shall be provided when needed.
The maximum anticipated working pressures in any hydraulic system on a mechanical power press shall not exceed the safe working pressure rating of any component used in that system.
All pressure vessels used in conjunction with power presses shall conform to the American Society of Mechanical Engineers Code for Pressure Vessels, 1968 Edition, which is incorporated by reference as specified in § 1910.6.
When required by paragraph (c)(5) of this section, the control system shall be constructed so that a failure within the system does not prevent the normal stopping action from being applied to the press when required, but does prevent initiation of a successive stroke until the failure is corrected. The failure shall be detectable by a simple test, or indicated by the control system. This requirement does not apply to those elements of the control system which have no effect on the protection against point of operation injuries.
When required by paragraph (c)(5) of this section, the brake monitor shall meet the following requirements:
s
s
where:
s
and
s
s
s
where:
s
and
s
m
m
where:
m
and
m
m
m
m
1/2
Hand feeding tools are intended for placing and removing materials in and from the press. Hand feeding tools are not a point of operation guard or protection device and shall not be used in lieu of the “guards” or devices required in this section.
Where the operator feeds or removes parts by placing one or both hands in the point of operation, and a two hand control, presence sensing device, Type B gate or movable barrier (on a part revolution clutch) is used for safeguarding:
The employer shall: (i) Use dies and operating methods designed to control or eliminate hazards to operating personnel, and (ii) furnish and enforce the use of hand tools for freeing and removing stuck work or scrap pieces from the die, so that no employee need reach into the point of operation for such purposes.
The employer shall provide means for handling scrap from roll feed or random length stock operations. Scrap cutters used in conjunction with scrap handling systems shall be safeguarded in accordance with paragraph (c) of this section and with § 1910.219.
The hazard created by a guide post (when it is located in the immediate vicinity of the operator) when separated from its bushing by more than one-fourth inch shall be considered as a point of operation hazard and be protected in accordance with paragraph (c) of this section.
If unitized tooling is used, the opening between the top of the punch holder and the face of the slide, or striking pad, shall be safeguarded in accordance with the requirements of paragraph (c) of this section.
Provision shall be made in both the upper and lower shoes for securely mounting the die to the bolster and slide. Where clamp caps or setscrews are used in conjunction with punch stems, additional means of securing the upper shoe to the slide shall be used.
Handling equipment attach points shall be provided on all dies requiring mechanical handling.
The employer shall establish and follow an inspection program having a general component and a directed component.
It shall be the responsibility of any person modifying a power press to furnish instructions with the modification to establish new or changed guidelines for use and care of the power press so modified.
It shall be the responsibility of the employer to insure the original and continuing competence of personnel caring for, inspecting, and maintaining power presses.
The employer shall train and instruct the operator in the safe method of work before starting work on any operation covered by this section. The employer shall insure by adequate supervision that correct operating procedures are being followed.
The employer shall provide clearance between machines so that movement of one operator will not interfere with the work of another. Ample room for cleaning machines, handling material, work pieces, and scrap shall also be provided. All surrounding floors shall be kept in good condition and free from obstructions, grease, oil, and water.
The employer shall operate his presses within the tonnage and attachment weight ratings specified by the manufacturer.
Explanation of above diagram:
This diagram shows the accepted safe openings between the bottom edge of a guard and feed table at various distances from the danger line (point of operation).
The clearance line marks the distance required to prevent contact between guard and moving parts.
The minimum guarding line is the distance between the infeed side of the guard and the danger line which is one-half inch from the danger line.
The various openings are such that for average size hands an operator's fingers won't reach the point of operation.
After installation of point of operation guards and before a job is released for operation a check should be made to verify that the guard will prevent the operator's hands from reaching the point of operation.
| Distance of opening from point of operation hazard | Maximum width of opening |
|---|---|
| 1 ⁄ 2 to 1 1 ⁄ 2 | 1 ⁄ 4 |
| 1 1 ⁄ 2 to 2 1 ⁄ 2 | 3 ⁄ 8 |
| 2 1 ⁄ 2 to 3 1 ⁄ 2 | 1 ⁄ 2 |
| 3 1 ⁄ 2 to 5 1 ⁄ 2 | 5 ⁄ 8 |
| 5 1 ⁄ 2 to 6 1 ⁄ 2 | 3 ⁄ 4 |
| 6 1 ⁄ 2 to 7 1 ⁄ 2 | 7 ⁄ 8 |
| 7 1 ⁄ 2 to 12 1 ⁄ 2 | 1 1 ⁄ 4 |
| 12 1 ⁄ 2 to 15 1 ⁄ 2 | 1 1 ⁄ 2 |
| 15 1 ⁄ 2 to 17 1 ⁄ 2 | 1 7 ⁄ 8 |
| 17 1 ⁄ 2 to 31 1 ⁄ 2 | 2 1 ⁄ 8 |
This table shows the distances that guards shall be positioned from the danger line in accordance with the required openings.
Presses whose designs incorporate flywheels running on journals on the crankshaft or back shaft, or bull gears running on journals mounted on the crankshaft, shall be inspected, lubricated, and maintained as provided in paragraph (h)(10) of this section to reduce the possibility of unintended and uncontrolled press strokes caused by bearing seizure.
set-up/reset means shall be provided which requires an overt action by the operator, in addition to PSDI mode selection, before operation of the press by means of PSDI can be started.
Control components shall be selected, constructed, and connected together in such a way as to withstand expected operational and environmental stresses, at least including those outlined in appendix A. Such stresses shall not so affect the control system as to cause unsafe operation.
shall be implemented only by use of light curtain (photo-electric) presence sensing devices which meet the requirements of paragraph (c)(3)(iii)( c ) of this section unless the requirements of the following paragraph have been met.
Ds = Hs × (Ts + Tp + Tr + 2Tm) + Dp
Where:
Ds = Minimum safety distance.
Hs = Hand speed constant of 63 inches per second (1.6 m/s).
Ts = Longest press stopping time, in seconds, computed by taking averages of multiple measurements at each of three positions (45 degrees, 60 degrees, and 90 degrees) of crankshaft angular position; the longest of the three averages is the stopping time to use. (Ts is defined as the sum of the kinetic energy dissipation time plus the pneumatic/magnetic/hydraulic reaction time of the clutch/brake operating mechanism(s).)
Tp = Longest presence sensing device response time, in seconds.
Tr = Longest response time, in seconds, of all interposing control elements between the presence sensing device and the clutch/brake operating mechanism(s).
Tm = Increase in the press stopping time at the top of the stroke, in seconds, allowed by the brake monitor for brake wear. The time increase allowed shall be limited to no more than 10 percent of the longest press stopping time measured at the top of the stroke, or 10 milliseconds, whichever is longer.
Dp = Penetration depth factor, required to provide for possible penetration through the presence sensing field by fingers or hand before detection occurs. The penetration depth factor shall be determined from Graph h-1 using the minimum object sensitivity size.
Where tools are used for feeding, removal of scrap, lubrication of parts, or removal of parts that stick on the die in PSDI operations:
Appendix A to § 1910.217—Mandatory Requirements for Certification/Validation of Safety Systems for Presence Sensing Device Initiation of Mechanical Power Presses
Purpose
The purpose of the certification/validation of safety systems for presence sensing device initiation (PSDI) of mechanical power presses is to ensure that the safety systems are designed, installed, and maintained in accordance with all applicable requirements of 29 CFR 1910.217 (a) through (h) and this appendix A.
General
The certification/validation process shall utilize an independent third-party validation organization recognized by OSHA in accordance with the requirements specified in appendix C of this section.
While the employer is responsible for assuring that the certification/validation requirements in § 1910.217(h)(11) are fulfilled, the design certification of PSDI safety systems may be initiated by manufacturers, employers, and/or their representatives. The term manufacturers refers to the manufacturer of any of the components of the safety system. An employer who assembles a PSDI safety system would be a manufacturer as well as employer for purposes of this standard and appendix.
The certification/validation process includes two stages. For design certification, in the first stage, the manufacturer (which can be an employer) certifies that the PSDI safety system meets the requirements of 29 CFR 1910.217 (a) through (h) and this appendix A, based on appropriate design criteria and tests. In the second stage, the OSHA-recognized third-party validation organization validates that the PSDI safety system meets the requirements of 29 CFR 1910.217 (a) through (h) and this appendix A and the manufacturer's certification by reviewing the manufacturer's design and test data and performing any additional reviews required by this standard or which it believes appropriate.
For installation certification/validation and annual recertification/revalidation, in the first stage the employer certifies or recertifies that the employer is installing or utilizing a PSDI safety system validated as meeting the design requirements of 29 CFR 1910.217 (a) through (h) and this appendix A by an OSHA-recognized third-party validation organization and that the installation, operation and maintenance meet the requirements of 29 CFR 1910.217 (a) through (h) and this appendix A. In the second stage, the OSHA-recognized third-party validation organization validates or revalidates that the PSDI safety system installation meets the requirements of 29 CFR 1910.217 (a) through (h) and this appendix A and the employer's certification, by reviewing that the PSDI safety system has been certified; the employer's certification, designs and tests, if any; the installation, operation, maintenance and training; and by performing any additional tests and reviews which the validation organization believes is necessary.
Summary
The certification/validation of safety systems for PSDI shall consider the press, controls, safeguards, operator, and environment as an integrated system which shall comply with all of the requirements in 29 CFR 1910.217 (a) through (h) and this appendix A. The certification/validation process shall verify that the safety system complies with the OSHA safety requirements as follows:
A. Design Certification/Validation
1. The major parts, components and subsystems used shall be defined by part number or serial number, as appropriate, and by manufacturer to establish the configuration of the system.
2. The identified parts, components and subsystems shall be certified by the manufacturer to be able to withstand the functional and operational environments of the PSDI safety system.
3. The total system design shall be certified by the manufacturer as complying with all requirements in 29 CFR 1910.217 (a) through (h) and this appendix A.
4. The third-party validation organization shall validate the manufacturer's certification under paragraphs 2 and 3.
B. Installation Certification/Validation
1. The employer shall certify that the PSDI safety system has been design certified and validated, that the installation meets the operational and environmental requirements specified by the manufacturer, that the installation drawings are accurate, and that the installation meets the requirements of 29 CFR 1910.217 (a) through (h) and this appendix A. (The operational and installation requirements of the PSDI safety system may vary for different applications.)
2. The third-party validation organization shall validate the employer's certifications that the PSDI safety system is design certified and validated, that the installation meets the installation and environmental requirements specified by the manufacturer, and that the installation meets the requirements of 29 CFR 1910.217 (a) through (h) and this appendix A.
C. Recertification/Revalidation
1. The PSDI safety system shall remain under certification/validation for the shorter of one year or until the system hardware is changed, modified or refurbished, or operating conditions are changed (including environmental, application or facility changes), or a failure of a critical component has occurred.
2. Annually, or after a change specified in paragraph 1., the employer shall inspect and recertify the installation as meeting the requirements set forth under B., Installation Certification/Validation.
3. The third-party validation organization, annually or after a change specified in paragraph 1., shall validate the employer's certification that the requirements of paragraph B., Installation Certification/Validation have been met.
Certification/Validation Requirements
A. General Design Certification/Validation Requirements
1. Certification/Validation Program Requirements. The manufacturer shall certify and the OSHA-recognized third-party validation organization shall validate that:
2. Certification/Validation Program Level of Risk Evaluation Requirements. The manufacturer shall evaluate and certify, and the OSHA-recognized third-party validation organization shall validate, the design and operation of the safety system by determining conformance with the following:
a. The safety system shall have the ability to sustain a single failure or a single operating error and not cause injury to personnel from point of operation hazards. Acceptable design features shall demonstrate, in the following order or precedence, that:
b. The manufacturer shall design, evaluate, test and certify, and the third-party validation organization shall evaluate and validate, that the PSDI safety system meets appropriate requirements in the following areas.
Design certification/validation for a new safety system, i.e., a new design or new integration of specifically identified components and subsystems, would entail a single certification/validation which would be applicable to all identical safety systems. It would not be necessary to repeat the tests on individual safety systems of the same manufacture or design. Nor would it be necessary to repeat these tests in the case of modifications where determined by the manufacturer and validated by the third-party validation organization to be equivalent by similarity analysis. Minor modifications not affecting the safety of the system may be made by the manufacturer without revalidation.
Substantial modifications would require testing as a new safety system, as deemed necessary by the validation organization.
B. Additional Detailed Design Certification/Validation Requirements
1. General. The manufacturer or the manufacturer's representative shall certify to and submit to an OSHA-recognized third-party validation organization the documentation necessary to demonstrate that the PSDI safety system design is in full compliance with the requirements of 29 CFR 1910.217(a)-
2. Reaction Times. For the purpose of demonstrating compliance with the reaction time required by § 1910.217(h), the tests shall use the following definitions and requirements:
a. Reaction time means the time, in seconds, it takes the signal, required to activate/deactivate the system, to travel through the system, measured from the time of signal initiation to the time the function being measured is completed.
b. Full stop or No movement of the slide or ram means when the crankshaft rotation has slowed to two or less revolutions per minute, just before stopping completely.
c. Function completion means for, electrical, electromechanical and electronic devices, when the circuit produces a change of state in the output element of the device.
d. When the change of state is motion, the measurement shall be made at the completion of the motion.
e. The generation of the test signal introduced into the system for measuring reaction time shall be such that the initiation time can be established with an error of less than 0.5 percent of the reaction time measured.
f. The instrument used to measure reaction time shall be calibrated to be accurate to within 0.001 second.
3. Compliance with § 1910.217(h)(2)(ii). For compliance with these requirements, the average value of the stopping time, Ts, shall be the arithmetic mean of at least 25 stops for each stop angle initiation measured with the brake and/or clutch unused, 50 percent worn, and 90 percent worn. The recommendations of the brake system manufacturer shall be used to simulate or estimate the brake wear. The manufacturer's recommended minimum lining depth shall be identified and documented, and an evaluation made that the minimum depth will not be exceeded before the next (annual) recertification/revalidation. A correlation of the brake and/or clutch degradation based on the above tests and/or estimates shall be made and documented. The results shall document the conditions under which the brake and/or clutch will and will not comply with the requirement. Based upon this determination, a scale shall be developed to indicate the allowable 10 percent of the stopping time at the top of the stroke for slide or ram overtravel due to brake wear. The scale shall be marked to indicate that brake adjustment and/or replacement is required. The explanation and use of the scale shall be documented.
The test specification and procedure shall be submitted to the validation organization for review and validation prior to the test. The validation organization representative shall witness at least one set of tests.
4. Compliance with §§ 1910.217(h)(5)(iii) and (h)(9)(v). Each reaction time required to calculate the Safety Distance, including the brake monitor setting, shall be documented in separate reaction time tests. These tests shall specify the acceptable tolerance band sufficient to assure that tolerance build-up will not render the safety distance unsafe.
a. Integrated test of the press fully equipped to operate in the PSDI mode shall be conducted to establish the total system reaction time.
b. Brakes which are the adjustable type shall be adjusted properly before the test.
5. Compliance with § 1910.217(h)(2)(iii). a. Prior to conducting the brake system test required by paragraph (h)(2)(ii), a visual check shall be made of the springs. The visual check shall include a determination that the spring housing or rod does not show damage sufficient to degrade the structural integrity of the unit, and the spring does not show any tendency to interleave.
b. Any detected broken or unserviceable springs shall be replaced before the test is conducted. The test shall be considered successful if the stopping time remains within that which is determined by paragraph (h)(9)(v) for the safety distance setting. If the increase in press stopping time exceeds the brake monitor setting limit defined in paragraph (h)(5)(iii), the test shall be considered unsuccessful, and the cause of the excessive stopping time shall be investigated. It shall be ascertained that the springs have not been broken and that they are functioning properly.
6. Compliance with § 1910.217(h)(7). a. Tests which are conducted by the manufacturers of electrical components to establish stress, life, temperature and loading limits must be tests which are in compliance with the provisions of the National Electrical Code.
b. Electrical and/or electronic cards or boards assembled with discreet components shall be considered a subsystem and shall require separate testing that the subsystems do not degrade in any of the following conditions:
c. The manufacturer shall specify the test requirements and procedures from existing consensus tests in compliance with the provisions of the National Electrical Code.
d. Tests designed by the manufacturer shall be made available upon request to the validation organization. The validation organization representative shall witness at least one set of each of these tests.
7. Compliance with § 1910.217(h)(9)(iv). a. The manufacturer shall design a test to demonstrate that the prescribed minimum object sensitivity of the presence sensing device is met.
b. The test specifications and procedures shall be made available upon request to the validation organization.
8. Compliance with § 1910.217(h)(9)(x). a. The manufacturer shall design a test(s) to establish the hand tool extension diameters allowed for variations in minimum object sensitivity response.
b. The test(s) shall document the range of object diameter sizes which will produce both single and double break conditions.
c. The test(s) specifications and procedures shall be made available upon request to the validation organization.
9. Integrated Tests Certification/Validation. a. The manufacturer shall design a set of integrated tests to demonstrate compliance with the following requirements:
Sections 1910.217(h)(6) (ii); (iii); (iv); (v); (vi); (vii); (viii); (ix); (xi); (xii); (xiii); (xiv); (xv); and (xvii).
b. The integrated test specifications and procedures shall be made available to the validation organization.
10. Analysis. a. The manufacturer shall submit to the validation organization the technical analysis such as Hazard Analysis, Failure Mode and Effect Analysis, Stress Analysis, Component and Material Selection Analysis, Fluid Compatability, and/or other analyses which may be necessary to demonstrate, compliance with the following requirements:
Sections 1910.217(h)(8) (i) and (ii); (h)(2) (ii) and (iii); (h)(3)(i) (A) and (C), and (ii); (h)(5) (i), (ii) and (iii); (h)(6) (i), (iii), (iv), (vi), (vii), (viii), (ix), (x), (xi), (xiii), (xiv), (xv), (xvi), and (xvii); (h)(7) (i) and (ii); (h)(9) (iv), (v), (viii), (ix) and (x); (h)(10) (i) and (ii).
11. Types of Tests Acceptable for Certification/Validation. a. Test results obtained from development testing may be used to certify/validate the design.
b. The test results shall provide the engineering data necessary to establish confidence that the hardware and software will meet specifications, the manufacturing process has adequate quality control and the data acquired was used to establish processes, procedures, and test levels supporting subsequent hardware design, production, installation and maintenance.
12. Validation for Design Certification/Validation. If, after review of all documentation, tests, analyses, manufacturer's certifications, and any additional tests which the third-party validation organization believes are necessary, the third-party validation organization determines that the PSDI safety system is in full compliance with the applicable requirements of 29 CFR 1910.217(a) through (h) and this appendix A, it shall validate the manufacturer's certification that it so meets the stated requirements.
C. Installation Certification/Validation Requirements
1. The employer shall evaluate and test the PSDI system installation, shall submit to the OSHA-recognized third-party validation organization the necessary supporting documentation, and shall certify that the requirements of § 1910.217(a) through (h) and this appendix A have been met and that the installation is proper.
2. The OSHA-recognized third-party validation organization shall conduct tests, and/or review and evaluate the employer's installation tests, documentation and representations. If it so determines, it shall validate the employer's certification that the PSDI safety system is in full conformance with all requirements of 29 CFR 1910.217(a) through (h) and this appendix A.
D. Recertification/Revalidation Requirements
1. A PSDI safety system which has received installation certification/validation shall undergo recertification/revalidation the earlier of:
a. Each time the systems hardware is significantly changed, modified, or refurbished;
b. Each time the operational conditions are significantly changed (including environmental, application or facility changes, but excluding such changes as die changes or press relocations not involving revision to the safety system);
c. When a failure of a significant component has occurred or a change has been made which may affect safety; or
d. When one year has elapsed since the installation certification/validation or the last recertification/revalidation.
2. Conduct or recertification/revalidation. The employer shall evaluate and test the PSDI safety system installation, shall submit to the OSHA-recognized third-party validation organization the necessary supporting documentation, and shall recertify that the requirements of § 1910.217(a) through (h) and this appendix are being met. The documentation shall include, but not be limited to, the following items:
a. Demonstration of a thorough inspection of the entire press and PSDI safety system to ascertain that the installation, components and safeguarding have not been changed, modified or tampered with since the installation certification/validation or last recertification/revalidation was made.
b. Demonstrations that such adjustments as may be needed (such as to the brake monitor setting) have been accomplished with proper changes made in the records and on such notices as are located on the press and safety system.
c. Demonstration that review has been made of the reports covering the design certification/validation, the installation certification/validation, and all recertification/revalidations, in order to detect any degradation to an unsafe condition, and that necessary changes have been made to restore the safety system to previous certification/validation levels.
3. The OSHA-recognized third-party validation organization shall conduct tests, and/or review and evaluate the employer's installation, tests, documentation and representations. If it so determines, it shall revalidate the employer's recertification that the PSDI system is in full conformance with all requirements of 29 CFR 1910.217(a) through (h) and this appendix A.
Appendix B to § 1910.217—Nonmandatory Guidelines for Certification/Validation of Safety Systems for Presence Sensing Device Initiation of Mechanical Power Presses
Objectives
This appendix provides employers, manufacturers, and their representatives, with nonmandatory guidelines for use in developing certification documents. Employers and manufacturers are encouraged to recommend other approaches if there is a potential for improving safety and reducing cost. The guidelines apply to certification/validation activity from design evaluation through the completion of the installation test and the annual recertification/revalidation tests.
General Guidelines
A. The certification/validation process should confirm that hazards identified by hazard analysis, (HA), failure mode effect analysis (FMEA), and other system analyses have been eliminated by design or reduced to an acceptable level through the use of appropriate design features, safety devices, warning devices, or special procedures. The certification/validation process should also confirm that residual hazards identified by operational analysis are addressed by warning, labeling safety instructions or other appropriate means.
B. The objective of the certification/validation program is to demonstrate and document that the system satisfies specification and operational requirements for safe operations.
Quality Control
The safety attributes of a certified/validated PSDI safety system are more likely to be maintained if the quality of the system and its parts, components and subsystem is consistently controlled. Each manufacturer supplying parts, components, subsystems, and assemblies needs to maintain the quality of the product, and each employer needs to maintain the system in a non-degraded condition.
Analysis Guidelines
A. Certification/validation of hardware design below the system level should be accomplished by test and/or analysis.
B. Analytical methods may be used in lieu of, in combination with, or in support of tests to satisfy specification requirements.
C. Analyses may be used for certification/validation when existing data are available or when test is not feasible.
D. Similarity analysis may be used in lieu of tests where it can be shown that the article is similar in design, manufacturing process, and quality control to another article that was previously certified/validated in accordance with equivalent or more stringent criteria. If previous design, history and application are considered to be similar, but not equal to or more exacting than earlier experiences, the additional or partial certification/validation tests should concentrate on the areas of changed or increased requirements.
Analysis Reports
The analysis reports should identify: (1) The basis for the analysis; (2) the hardware or software items analyzed; (3) conclusions; (4) safety factors; and (5) limit of the analysis. The assumptions made during the analysis should be clearly stated and a description of the effects of these assumptions on the conclusions and limits should be included.
Certification/validation by similarity analysis reports should identify, in addition to the above, application of the part, component or subsystem for which certification/validation is being sought as well as data from previous usage establishing adequacy of the item. Similarity analysis should not be accepted when the internal and external stresses on the item being certified/validated are not defined.
Usage experience should also include failure data supporting adequacy of the design.
Appendix C to § 1910.217—Mandatory Requirements for OSHA Recognition of Third-Party Validation Organizations for the PSDI Standard
This appendix prescribes mandatory requirements and procedures for OSHA recognition of third-party validation organizations to validate employer and manufacturer certifications that their equipment and practices meet the requirements of the PSDI standard. The scope of the appendix includes the three categories of certification/validation required by the PSDI standard: Design Certification/Validation, Installation Certification/Validation, and Annual Recertification/Revalidation.
If further detailing of these provisions will assist the validation organization or OSHA in this activity, this detailing will be done through appropriate OSHA Program Directives.
I. Procedure for OSHA Recognition of Validation Organizations
A. Applications
1. Eligibility. a. Any person or organization considering itself capable of conducting a PSDI-related third-party validation function may apply for OSHA recognition.
b. However, in determining eligibility for a foreign-based third-party validation organization, OSHA shall take into consideration whether there is reciprocity of treatment by the foreign government after consultation with relevant U.S. government agencies.
2. Content of application. a. The application shall identify the scope of the validation activity for which the applicant wishes to be recognized, based on one of the following alternatives:
b. The application shall provide information demonstrating that it and any validating laboratory utilized meet the qualifications set forth in section II of this appendix.
c. The applicant shall provide information demonstrating that it and any validating laboratory utilized meet the program requirements set forth in section III of this appendix.
d. The applicant shall identify the test methods it or the validating laboratory will use to test or judge the components and operations of the PSDI safety system required to be tested by the PSDI standard and appendix A, and shall specify the reasons the test methods are appropriate.
e. The applicant may include whatever enclosures, attachments, or exhibits the applicant deems appropriate. The application need not be submitted on a Federal form.
f. The applicant shall certify that the information submitted is accurate.
3. Filing office location. The application shall be filed with: PSDI Certification/Validation Program, Office of Variance Determination, Occupational Safety and Health Administration, U.S. Department of Labor, Room N3653, 200 Constitution Avenue, NW., Washington, DC 20210.
4. Amendments and withdrawals. a. An application may be revised by an applicant at any time prior to the completion of the final staff recommendation.
b. An application may be withdrawn by an applicant, without prejudice, at any time prior to the final decision by the Assistant Secretary in paragraph I.B.8.b.
B. Review and Decision Process
1. Acceptance and field inspection. All applications submitted will be accepted by OSHA, and their receipt acknowledged in writing. After receipt of an application, OSHA may request additional information if it believes information relevant to the requirements for recognition have been omitted. OSHA may inspect the facilities of the third-party validation organization and any validating laboratory, and while there shall review any additional documentation underlying the application. A report shall be made of each field inspection.
2. Requirements for recognition. The requirements for OSHA recognition of a third-party validation organization for the PSDI standard are that the program has fulfilled the requirements of section II of this appendix for qualifications and of section III of this appendix for program requirements, and the program has identified appropriate test and analysis methods to meet the requirements of the PSDI standard and appendix A.
3. Preliminary approval. If, after review of the application, any additional information, and the inspection report, the applicant and any validating laboratory appear to have met the requirements for recognition, a written recommendation shall be submitted by the responsible OSHA personnel to the Assistant Secretary to approve the application with a supporting explanation.
4. Preliminary disapproval. If, after review of the application, additional information, and inspection report, the applicant does not appear to have met the requirements for recognition, the Director of the PSDI certification/validation program shall notify the applicant in writing, listing the specific requirements of this appendix which the applicant has not met, and the reasons.
5. Revision of application. After receipt of a notification of preliminary disapproval, the applicant may submit a revised application for further review by OSHA pursuant to subsection I.B. of this appendix or may request that the original application be submitted to the Assistant Secretary with a statement of reasons supplied by the applicant as to why the application should be approved.
6. Preliminary decision by Assistant Secretary. a. The Assistant Secretary, or a special designee for this purpose, will make a preliminary decision whether the applicant has met the requirements for recognition based on the completed application file and the written staff recommendation, as well as the statement of reasons by the applicant if there is a recommendation of disapproval.
b. This preliminary decision will be sent to the applicant and subsequently published in the Federal Register.
7. Public review and comment period. a. The Federal Register notice of preliminary decision will provide a period of not less than 60 calendar days for the written comments on the applicant's fulfillment of the requirements for recognition. The application, supporting documents, staff recommendation, statement of applicant's reasons, and any comments received, will be available for public inspection in the OSHA Docket Office.
b. If the preliminary decision is in favor of recognition, a member of the public, or if the preliminary decision is against recognition, the applicant may request a public hearing by the close of the comment period, if it supplies detailed reasons and evidence challenging the basis of the Assistant Secretary's preliminary decision and justifying the need for a public hearing to bring out evidence which could not be effectively supplied through written submissions.
8. Final decision by Assistant Secretary —a. Without hearing. If there are no valid requests for a hearing, based on the application, supporting documents, staff recommendation, evidence and public comment, the Assistant Secretary shall issue the final decision (including reasons) of the Department of Labor on whether the applicant has demonstrated by a preponderance of the evidence that it meets the requirements for recognition.
b. After hearing. If there is a valid request for a hearing pursuant to paragraph I.B.7.b. of this appendix, the following procedures will be used:
b. Publication. A notification of the final decision shall be published in the Federal Register.
C. Terms and Conditions of Recognition, Renewal and Revocation
1. The following terms and conditions shall be part of every recognition:
a. The recognition of any validation organization will be evidenced by a letter of recognition from OSHA. The letter will provide the specific details of the scope of the OSHA recognition as well as any conditions imposed by OSHA, including any Federal monitoring requirements.
b. The recognition of each validation organization will be valid for five years, unless terminated before or renewed after the expiration of the period. The dates of the period of recognition will be stated in the recognition letter.
c. The recognized validation organization shall continue to satisfy all the requirements of this appendix and the letter of recognition during the period of recognition.
2. A recognized validation organization may change a test method of the PSDI safety system certification/validation program by notifying the Assistant Secretary of the change, certifying that the revised method will be at least as effective as the prior method, and providing the supporting data upon which its conclusions are based.
3. A recognized validation organization may renew its recognition by filing a renewal request at the address in paragraph I.A.3. of this appendix, above, not less than 180 calendar days, nor more than one year, before the expiration date of its current recognition. When a recognized validation organization has filed such a renewal request, its current recognition will not expire until a final decision has been made on the request. The renewal request will be processed in accordance with subsection I.B. of this appendix, above, except that a reinspection is not required but may be performed by OSHA. A hearing will be granted to an objecting member of the public if evidence of failure to meet the requirements of this appendix is supplied to OSHA.
4. A recognized validation organization may apply to OSHA for an expansion of its current recognition to cover other categories of PSDI certification/validation in addition to those included in the current recognition. The application for expansion will be acted upon and processed by OSHA in accordance with subsection I.B. of this appendix, subject to the possible reinspection exception. If the validation organization has been recognized for more than one year, meets the requirements for expansion of recognition, and there is no evidence that the recognized validation organization has not been following the requirements of this appendix and the letter of recognition, an expansion will normally be granted. A hearing will be granted to an objecting member of the public only if evidence of failure to meet the requirements of this appendix is supplied to OSHA.
5. A recognized validation organization may voluntarily terminate its recognition, either in its entirety or with respect to any area covered in its recognition, by giving written notice to OSHA at any time. The written notice shall indicate the termination date. A validation organization may not terminate its installation certification and recertification validation functions earlier than either one year from the date of the written notice, or the date on which another recognized validation organization is able to perform the validation of installation certification and recertification.
6.a. OSHA may revoke its recognition of a validation organization if its program either has failed to continue to satisfy the requirements of this appendix or its letter of recognition, has not been performing the validation functions required by the PSDI standard and appendix A, or has misrepresented itself in its applications. Before proposing to revoke recognition, the Agency will notify the recognized validation organization of the basis of the proposed revocation and will allow rebuttal or correction of the alleged deficiencies. If the deficiencies are not corrected, OSHA may revoke recognition, effective in 60 days, unless the validation organization requests a hearing within that time.
b. If a hearing is requested, it shall be held before an administrative law judge of the Department of Labor pursuant to the rules specified in 29 CFR part 1905, subpart C.
c. The parties shall be OSHA and the recognized validation organization. The decision shall be made pursuant to the procedures specified in paragraphs I.B.8.b.
D. Provisions of OSHA Recognition
Each recognized third-party validation organization and its validating laboratories shall:
1. Allow OSHA to conduct unscheduled reviews or on-site audits of it or the validating laboratories on matters relevant to PSDI, and cooperate in the conduct of these reviews and audits;
2. Agree to terms and conditions established by OSHA in the grant of recognition on matters such as exchange of data, submission of accident reports, and assistance in studies for improving PSDI or the certification/validation process.
II. Qualifications
The third-party validation organization, the validating laboratory, and the employees of each shall meet the requirements set forth in this section of this appendix.
A. Experience of Validation Organization
1. The third-party validation organization shall have legal authority to perform certification/validation activities.
2. The validation organization shall demonstrate competence and experience in either power press design, manufacture or use, or testing, quality control or certification/validation of equipment comparable to power presses and associated control systems.
3. The validation organization shall demonstrate a capability for selecting, reviewing, and/or validating appropriate standards and test methods to be used for validating the certification of PSDI safety systems, as well as for reviewing judgements on the safety of PSDI safety systems and their conformance with the requirements of this section.
4. The validating organization may utilize the competence, experience, and capability of its employees to demonstrate this competence, experience and capability.
B. Independence of Validation Organization
1. The validation organization shall demonstrate that:
a. It is financially capable to conduct the work;
b. It is free of direct influence or control by manufacturers, suppliers, vendors, representatives of employers and employees, and employer or employee organizations; and
c. Its employees are secure from discharge resulting from pressures from manufacturers, suppliers, vendors, employers or employee representatives.
2. A validation organization may be considered independent even if it has ties with manufacturers, employers or employee representatives if these ties are with at least two of these three groups; it has a board of directors (or equivalent leadership responsible for the certification/validation activities) which includes representatives of the three groups; and it has a binding commitment of funding for a period of three years or more.
C. Validating Laboratory
The validation organization's laboratory (which organizationally may be a part of the third-party validation organization):
1. Shall have legal authority to perform the validation of certification;
2. Shall be free of operational control and influence of manufacturers, suppliers, vendors, employers, or employee representatives that would impair its integrity of performance; and
3. Shall not engage in the design, manufacture, sale, promotion, or use of the certified equipment.
D. Facilities and Equipment
The validation organization's validating laboratory shall have available all testing facilities and necessary test and inspection equipment relevant to the validation of the certification of PSDI safety systems, installations and operations.
E. Personnel
The validation organization and the validating laboratory shall be adequately staffed by personnel who are qualified by technical training and/or experience to conduct the validation of the certification of PSDI safety systems.
1. The validation organization shall assign overall responsibility for the validation of PSDI certification to an Administrative Director. Minimum requirements for this position are a Bachelor's degree and five years professional experience, at least one of which shall have been in responsible charge of a function in the areas of power press design or manufacture or a broad range of power press use, or in the areas of testing, quality control, or certification/validation of equipment comparable to power presses or their associated control systems.
2. The validating laboratory, if a separate organization from the validation organization, shall assign technical responsibility for the validation of PSDI certification to a Technical Director. Minimum requirements for this position are a Bachelor's degree in a technical field and five years of professional experience, at least one of which shall have been in responsible charge of a function in the area of testing, quality control or certification/validation of equipment comparable to power presses or their associated control systems.
3. If the validation organization and the validating laboratory are the same organization, the administrative and technical responsibilities may be combined in a single position, with minimum requirements as described in E.1. and 2. for the combined position.
4. The validation organization and validating laboratory shall have adequate administrative and technical staffs to conduct the validation of the certification of PSDI safety systems.
F. Certification/Validation Mark or Logo
1. The validation organization or the validating laboratory shall own a registered certification/validation mark or logo.
2. The mark or logo shall be suitable for incorporation into the label required by paragraph (h)(11)(iii) of this section.
III. Program Requirements
A. Test and Certification/Validation Procedures
1. The validation organization and/or validating laboratory shall have established written procedures for test and certification/validation of PSDI safety systems. The procedures shall be based on pertinent OSHA standards and test methods, or other publicly available standards and test methods generally recognized as appropriate in the field, such as national consensus standards or published standards of professional societies or trade associations.
2. The written procedures for test and certification/validation of PSDI systems, and the standards and test methods on which they are based, shall be reproducible and be available to OSHA and to the public upon request.
B. Test Reports
1. A test report shall be prepared for each PSDI safety system that is tested. The test report shall be signed by a technical staff representative and the Technical Director.
2. The test report shall include the following:
a. Name of manufacturer and catalog or model number of each subsystem or major component.
b. Identification and description of test methods or procedures used. (This may be through reference to published sources which describe the test methods or procedures used.)
c. Results of all tests performed.
d. All safety distance calculations.
3. A copy of the test report shall be maintained on file at the validation organization and/or validating laboratory, and shall be available to OSHA upon request.
C. Certification/Validation Reports
1. A certification/validation report shall be prepared for each PSDI safety system for which the certification is validated. The certification/validation report shall be signed by the Administrative Director and the Technical Director.
2. The certification/validation report shall include the following:
a. Name of manufacturer and catalog or model number of each subsystem or major component.
b. Results of all tests which serve as the basis for the certification.
c. All safety distance calculations.
d. Statement that the safety system conforms with all requirements of the PSDI standard and appendix A.
3. A copy of the certification/validation report shall be maintained on file at the validation organization and/or validating laboratory, and shall be available to the public upon request.
4. A copy of the certification/validation report shall be submitted to OSHA within 30 days of its completion.
D. Publications System
The validation organization shall make available upon request a list of PSDI safety systems which have been certified/validated by the program.
E. Follow-up Activities
1. The validation organization or validating laboratory shall have a follow-up system for inspecting or testing manufacturer's production of design certified/validated PSDI safety system components and subassemblies where deemed appropriate by the validation organization.
2. The validation organization shall notify the appropriate product manufacturer(s) of any reports from employers of point of operation injuries which occur while a press is operated in a PSDI mode.
F. Records
The validation organization or validating laboratory shall maintain a record of each certification/validation of a PSDI safety system, including manufacturer and/or employer certification documentation, test and working data, test report, certification/validation report, any follow-up inspections or testing, and reports of equipment failures, any reports of accidents involving the equipment, and any other pertinent information. These records shall be available for inspection by OSHA and OSHA State Plan offices.
G. Dispute Resolution Procedures
1. The validation organization shall have a reasonable written procedure for acknowledging and processing appeals or complaints from program participants (manufacturers, producers, suppliers, vendors and employers) as well as other interested parties (employees or their representatives, safety personnel, government agencies, etc.), concerning certification or validation.
2. The validation organization may charge any complainant the reasonable charge for repeating tests needed for the resolution of disputes.
Appendix D to § 1910.217—Nonmandatory Supplementary Information
This appendix provides nonmandatory supplementary information and guidelines to assist in the understanding and use of 29 CFR 1910.217(h) to allow presence sensing device initiation (PSDI) of mechanical power presses. Although this appendix as such is not mandatory, it references sections and requirements which are made mandatory by other parts of the PSDI standard and appendices.
1. General
OSHA intends that PSDI continue to be prohibited where present state-of-the-art technology will not allow it to be done safely. Only part revolution type mechanical power presses are approved for PSDI. Similarly, only presses with a configuration such that a person's body cannot completely enter the bed area are approved for PSDI.
2. Brake and Clutch
Flexible steel band brakes do not possess a long-term reliability against structural failure as compared to other types of brakes, and therefore are not acceptable on presses used in the PSDI mode of operation.
Fast and consistent stopping times are important to safety for the PSDI mode of operation. Consistency of braking action is enhanced by high brake torque. The requirement in paragraph (h)(2)(ii) defines a high torque capability which should ensure fast and consistent stopping times.
Brake design parameters important to PSDI are high torque, low moment of inertia, low air volume (if pneumatic) mechanisms, non-interleaving engagement springs, and structural integrity which is enhanced by over-design. The requirement in paragrpah (h)(2)(iii) reduces the possibility of significantly increased stopping time if a spring breaks.
As an added precaution to the requirements in paragraph (h)(2)(iii), brake adjustment locking means should be secured. Where brake springs are externally accessible, lock nuts or other means may be provided to reduce the possibility of backing off of the compression nut which holds the springs in place.
3. Pneumatic Systems
Elevated clutch/brake air pressure results in longer stopping time. The requirement in paragraph (h)(3)(i)( C ) is intended to prevent degradation in stoping speed from higher air pressure. Higher pressures may be permitted, however, to increase clutch torque to free “jammed” dies, provided positive measures are provided to prevent the higher pressure at other times.
4. Flywheels and Bearings
Lubrication of bearings is considered the single greatest deterrent to their failure. The manufacturer's recommended procedures for maintenance and inspection should be closely followed.
5. Brake Monitoring
The approval of brake monitor adjustments, as required in paragraph (h)(5)(ii), is not considered a recertification, and does not necessarily involve an on-site inspection by a representative of the validation organization. It is expected that the brake monitor adjustment normally could be evaluated on the basis of the effect on the safety system certification/validation documentation retained by the validation organization.
Use of a brake monitor does not eliminate the need for periodic brake inspection and maintenance to reduce the possibility of catastrophic failures.
6. Cycle Control and Control Systems
The PSDI set-up/reset means required by paragraph (h)(6)(iv) may be initiated by the actuation of a special momentary pushbutton or by the actuation of a special momentary pushbutton and the initiation of a first stroke with two hand controls.
It would normally be preferable to limit the adjustment of the time required in paragraph (h)(6)(vi) to a maximum of 15 seconds. However, where an operator must do many operations outside the press, such as lubricating, trimming, deburring, etc., a longer interval up to 30 seconds is permitted.
When a press is equipped for PSDI operation, it is recommended that the presence sensing device be active as a guarding device in other production modes. This should enhance the reliability of the device and ensure that it remains operable.
An acceptable method for interlocking supplemental guards as required by paragraph (h)(6)(xiii) would be to incorporate the supplemental guard and the PSDI presence sensing device into a hinged arrangement in which the alignment of the presence sensing device serves, in effect, as the interlock. If the supplemental guards are moved, the presence sensing device would become misaligned and the press control would be deactivated. No extra microswitches or interlocking sensors would be required.
Paragraph (h)(6)(xv) of the standard requires that the control system have provisions for an “inch” operating means; that die-setting not be done in the PSDI mode; and that production not be done in the “inch” mode. It should be noted that the sensing device would be by-passed in the “inch” mode. For that reason, the prohibitions against die-setting in the PSDI mode, and against production in the “inch” mode are cited to emphasize that “inch” operation is of reduced safety and is not compatible with PSDI or other production modes.
7. Environmental Requirements
It is the intent of paragraph (h)(7) that control components be provided with inherent design protection against operating stresses and environmental factors affecting safety and reliability.
8. Safety system
The safety system provision continues the concept of paragraph (b)(13) that the probability of two independent failures in the length of time required to make one press cycle is so remote as to be a negligible risk factor in the total array of equipment and human factors. The emphasis is on an integrated total system including all elements affecting point of operation safety.
It should be noted that this does not require redundancy for press components such as structural elements, clutch/brake mechanisms, plates, etc., for which adequate reliability may be achieved by proper design, maintenance, and inspection.
9. Safeguarding the Point of Operation
The intent of paragraph (h)(9)(iii) is to prohibit use of mirrors to “bend” a single light curtain sensing field around corners to cover more than one side of a press. This prohibition is needed to increase the reliability of the presence sensing device in initiating a stroke only when the desired work motion has been completed.
Object sensitivity describes the capability of a presence sensing device to detect an object in the sensing field, expressed as the linear measurement of the smallest interruption which can be detected at any point in the field. Minimum object sensitivity describes the largest acceptable size of the interruption in the sensing field. A minimum object sensitivity of one and one-fourth inches (31.75 mm) means that a one and one-fourth inch (31.75 mm) diameter object will be continuously detected at all locations in the sensing field.
In deriving the safety distance required in paragraph (h)(9)(v), all stopping time measurements should be made with clutch/brake air pressure regulated to the press manufacturer's recommended value for full clutch torque capability. The stopping time measurements should be made with the heaviest upper die that is planned for use in the press. If the press has a slide counterbalance system, it is important that the counterbalance be adjusted correctly for upper die weight according to the manufacturer's instructions. While the brake monitor setting is based on the stopping time it actually measures, i.e., the normal stopping time at the top of the stroke, it is important that the safety distance be computed from the longest stopping time measured at any of the indicated three downstroke stopping positions listed in the explanation of Ts. The use in the formula of twice the stopping time increase, Tm, allowed by the brake monitor for brake wear allows for greater increases in the downstroke stopping time than occur in normal stopping time at the top of the stroke.
10. Inspection and Maintenance. [Reserved]
11. Safety System Certification/Validation
Mandatory requirements for certification/validation of the PSDI safety system are provided in appendix A and appendix C to this standard. Nonmandatory supplementary information and guidelines relating to certification/validation of the PSDI safety system are provided to appendix B to this standard.
[39 FR 23502, June 27, 1974, as amended at 39 FR 41846, Dec. 3, 1974; 40 FR 3982, Jan. 27, 1975; 43 FR 49750, Oct. 24, 1978; 45 FR 8594, Feb. 8, 1980; 49 FR 18295, Apr. 30, 1984; 51 FR 34561, Sept. 29, 1986; 53 FR 8353, 8358 Mar. 14, 1988; 54 FR 24333, June 7, 1989; 61 FR 9240, Mar. 7, 1996; 69 FR 31882, June 8, 2004; 76 FR 80739, Dec. 27, 2011; 77 FR 46949, Aug. 7, 2012; 78 FR 69550, Nov. 20, 2013]
The safety requirements of this subparagraph apply to lead casts or other use of lead in the forge shop or die shop.
It shall be the responsibility of the employer to maintain all forge shop equipment in a condition which will insure continued safe operation. This responsibility includes:
| Size of timber, inches 1 | Square inches in cross section | Minimum allowable crushing strength parallel to grain, p.s.i. 2 | Maximum static load within short column range 3 | Safety factor | Maximum recommended weight of forging hammer for timber used | Maximum allowable length of timber, inches |
|---|---|---|---|---|---|---|
| 4 × 4 | 16 | 5,000 | 80,000 | 10 | 8,000 | 44 |
| 6 × 6 | 36 | 5,000 | 180,000 | 10 | 18,000 | 66 |
| 8 × 8 | 64 | 5,000 | 320,000 | 10 | 32,000 | 88 |
| 10 × 10 | 100 | 5,000 | 500,000 | 10 | 50,000 | 100 |
| 12 × 12 | 144 | 5,000 | 720,000 | 10 | 72,000 | 132 |
| 1 Actual dimension. | ||||||
| 2 Adapted from U.S. Department of Agriculture Technical Bulletin 479. Hardwoods recommended are those whose ultimate crushing strengths in compression parallel to grain are 5,000 p.s.i. (pounds per square inch) or greater. | ||||||
| 3 Slenderness ratio formula for short columns is L/d = 11, where L = length of timber in inches and d = least dimension in inches; this ratio should not exceed 11. |
Die keys and shims shall be made from a grade of material that will not unduly crack or splinter.
All foot operated devices (i.e., treadles, pedals, bars, valves, and switches) shall be substantially and effectively protected from unintended operation.
All manually operated valves and switches shall be clearly identified and readily accessible.
Every steam or airhammer shall have a safety cylinder head to act as a cushion if the rod should break or pullout of the ram.
Steam hammers shall be provided with a quick closing emergency valve in the admission pipeline at a convenient location. This valve shall be closed and locked in the off position while the hammer is being adjusted, repaired, or serviced, or when the dies are being changed.
Steam hammers shall be provided with a means of cylinder draining, such as a self-draining arrangement or a quick-acting drain cock.
Steam or air piping shall conform to the specifications of American National Standard ANSI B31.1.0-1967, Power Piping with Addenda issued before April 28, 1971, which is incorporated by reference as specified in § 1910.6.
When dies are being changed or maintenance is being performed on the press, the following shall be accomplished:
When dies are being changed or maintenance is being performed on the press, the following shall be accomplished:
The requirements of paragraph (f)(1) of this section shall also apply to hot trimming presses.
Cold trimming presses shall be safeguarded in accordance with § 1910.217(c).
All upsetters shall be installed so that they remain on their supporting foundations.
Upsetters shall be provided with a means for locking out the power at its entry point to the machine and rendering its cycling controls inoperable.
All manually operated valves and switches shall be clearly identified and readily accessible.
Tongs shall be of sufficient length to clear the body of the worker in case of kickback, and shall not have sharp handle ends.
When dies are being changed, maintenance performed, or any work done on the machine, the power to the upsetter shall be locked out, and the flywheel shall be at rest.
The provisions of paragraph (h) of this section shall apply to boltheading.
The provisions of paragraph (h) of this section shall apply to rivet making.
A positive-type lockout device for disconnecting the power to the shear shall be provided.
Every saw shall be provided with a guard of not less than one-eighth inch sheet metal positioned to stop flying sparks.
Conveyor power transmission equipment shall be guarded in accordance with ANSI B20.1-1957, Safety Code for Conveyors, Cableways, and Related Equipment, which is incorporated by reference as specified in § 1910.6.
The cleaning chamber shall have doors or guards to protect operators.
Personal protective equipment shall be used in grinding operations, and equipment shall be used and maintained in accordance with ANSI B7.1-1970, Safety Code for the Use, Care, and Protection of Abrasive Wheels, which is incorporated by reference as specified in § 1910.6, and with § 1910.215.
[39 FR 23502, June 27, 1974, as amended at 49 FR 5323, Feb. 10, 1984; 51 FR 34561, Sept. 29, 1986; 61 FR 9240, Mar. 7, 1996]
Flywheels located so that any part is seven (7) feet or less above floor or platform shall be guarded in accordance with the requirements of this subparagraph:
Cranks and connecting rods, when exposed to contact, shall be guarded in accordance with paragraphs (m) and (n) of this section, or by a guardrail as described in paragraph (o)(5) of this section.
Tail rods or extension piston rods shall be guarded in accordance with paragraphs (m) and (o) of this section, or by a guardrail on sides and end, with a clearance of not less than fifteen (15) nor more than twenty (20) inches when rod is fully extended.
Vertical and inclined shafting seven (7) feet or less from floor or working platform, excepting maintenance runways, shall be enclosed with a stationary casing in accordance with requirements of paragraphs (m) and (o) of this section.
All mechanical power transmission apparatus located in basements, towers, and rooms used exclusively for power transmission equipment shall be guarded in accordance with this section, except that the requirements for safeguarding belts, pulleys, and shafting need not be complied with when the following requirements are met:
Pulleys, any parts of which are seven (7) feet or less from the floor or working platform, shall be guarded in accordance with the standards specified in paragraphs (m) and (o) of this section. Pulleys serving as balance wheels (e.g., punch presses) on which the point of contact between belt and pulley is more than six feet six inches (6 ft. 6 in.) from the floor or platform may be guarded with a disk covering the spokes.
Pulleys with cracks, or pieces broken out of rims, shall not be used.
Pulleys intended to operate at rim speed in excess of manufacturers normal recommendations shall be specially designed and carefully balanced for the speed at which they are to operate.
Vertical belts running over a lower pulley more than seven (7) feet above floor or platform shall be guarded at the bottom in the same manner as horizontal overhead belts, if conditions are as stated in paragraphs (e)(2)(ii) ( a ) and ( c ) of this section.
Gears shall be guarded in accordance with one of the following methods:
Paragraph (f)(1) of this section does not apply to hand-operated gears used only to adjust machine parts and which do not continue to move after hand power is removed. However, the guarding of these gears is highly recommended.
All sprocket wheels and chains shall be enclosed unless they are more than seven (7) feet above the floor or platform. Where the drive extends over other machine or working areas, protection against falling shall be provided. This subparagraph does not apply to manually operated sprockets.
When frequent oiling must be done, openings with hinged or sliding self-closing covers shall be provided. All points not readily accessible shall have oil feed tubes if lubricant is to be added while machinery is in motion.
The driving point of all friction drives when exposed to contact shall be guarded, all arm or spoke friction drives and all web friction drives with holes in the web shall be entirely enclosed, and all projecting belts on friction drives where exposed to contact shall be guarded.
All revolving collars, including split collars, shall be cylindrical, and screws or bolts used in collars shall not project beyond the largest periphery of the collar.
Shaft couplings shall be so constructed as to present no hazard from bolts, nuts, setscrews, or revolving surfaces. Bolts, nuts, and setscrews will, however, be permitted where they are covered with safety sleeves or where they are used parallel with the shafting and are countersunk or else do not extend beyond the flange of the coupling.
All drip cups and pans shall be securely fastened.
Clutches, cutoff couplings, or clutch pulleys having projecting parts, where such clutches are located seven (7) feet or less above the floor or working platform, shall be enclosed by a stationary guard constructed in accordance with this section. A “U” type guard is permissible.
In engine rooms a guardrail, preferably with toeboard, may be used instead of the guard required by paragraph (k)(1) of this section, provided such a room is occupied only by engine room attendants.
The use of belt poles as substitutes for mechanical shifters is not recommended.
Where loose pulleys or idlers are not practicable, belt perches in form of brackets, rollers, etc., shall be used to keep idle belts away from the shafts.
Belts which of necessity must be shifted by hand and belts within seven (7) feet of the floor or working platform which are not guarded in accordance with this section shall not be fastened with metal in any case, nor with any other fastening which by construction or wear will constitute an accident hazard.
The materials and dimensions specified in this paragraph shall apply to all guards, except horizontal overhead belts, rope, cable, or chain guards more than seven (7) feet above floor, or platform.
Overhead-rope and chain-drive guard construction shall conform to the rules for overhead-belt guard.
All power-transmission equipment shall be inspected at intervals not exceeding 60 days and be kept in good working condition at all times.
Bearings shall be kept in alignment and properly adjusted.
Hangers shall be inspected to make certain that all supporting bolts and screws are tight and that supports of hanger boxes are adjusted properly.
The regular oilers shall wear tight-fitting clothing. Machinery shall be oiled when not in motion, wherever possible.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49750, Oct. 24, 1978; 43 FR 51760; Nov. 7, 1978; 49 FR 5323, Feb. 10, 1984; 61 FR 9240, Mar. 7, 1996; 69 FR 31882, June 8, 2004]
As used in this subpart:
low-velocity type. A tool which, by means of a heavy mass hammer supplemented by a load, moves a piston designed to be captive to drive a stud, pin, or fastener into a work surface, always starting the fastener at rest and in contact with the work surface. It shall be so designed that when used with any load that accurately chambers in it and that is commercially available at the time the tool is submitted for approval, it will not cause such stud, pin, or fastener to have a mean velocity in excess of 300 feet per second when measured 6.5 feet from the muzzle end of the barrel.
A tool or machine which, when used with a load, propels or discharges a stud, pin, or fastener, at velocities in excess of 300 feet per second when measured 6.5 feet from the muzzle end of the barrel, for the purpose of impinging it upon, affixing it to, or penetrating another object or material.
A tool that utilizes a piston designed to be captive to drive a stud, pin, or fastener into a work surface. It shall be so designed that when used with any load that accurately chambers in it and that is commercially available at the time the tool is submitted for approval, it will not cause such stud, pin, or fastener to have a mean velocity in excess of 300 feet per second when measured 6.5 feet from the muzzle end of the barrel.
To fit properly without the use of excess force, the case being duly supported.
An explosive-actuated fastening tool, unless otherwise indicated, and all accessories pertaining thereto.
A device or guard attached to the muzzle end of the tool, which is designed to confine flying particles.
Mounted wheels, usually 2-inch diameter or smaller, and of various shapes, may be either organic or inorganic bonded abrasive wheels. They are secured to plain or threaded steel mandrels.
Removal, by grinding, of cement, mortar, or other nonmetallic jointing material.
Tuck pointing wheels, usually Type 1, reinforced organic bonded wheels have diameter, thickness and hole size dimension. They are subject to the same limitations of use and mounting as Type 1 wheels defined in subparagraph (10) of this paragraph.
Limitation: Wheels used for tuck pointing should be reinforced, organic bonded. (See § 1910.243(c)(1)(ii)( c. ))
A grinding operation where the grinding machine is designed to be hand held and may be easily moved from one location to another.
Organic wheels are wheels which are bonded by means of an organic material such as resin, rubber, shellac, or other similar bonding agent.
A safety guard is an enclosure designed to restrain the pieces of the grinding wheel and furnish all possible protection in the event that the wheel is broken in operation.
The term reinforced as applied to grinding wheels shall define a class of organic wheels which contain strengthening fabric or filament. The term reinforced does not cover wheels using such mechanical additions as steel rings, steel cup backs or wire or tape winding.
Type 11 flaring cup wheels have double diameter dimensions D and J, and in addition have thickness, hole size, rim and back thickness dimensions. Grinding is always performed on rim face, W dimension. Type 11 wheels are subject to all limitations of use and mounting listed for Type 6 straight sided cup wheels definition in subparagraph (9) of this paragraph.
Type 11 Flaring Cup Wheels
Type 11—Flaring-cup Wheel
Side grinding wheel having a wall flared or tapered outward from the back. Wall thickness at the back is normally greater than at the grinding face (W).
Limitation: Minimum back thickness, E dimension, should not be less than one-fourth T dimension. In addition when unthreaded hole wheels are specified the inside flat, K dimension, shall be large enough to accommodate a suitable flange.
Type 6 cup wheels have diameter, thickness, hole size, rim thickness, and back thickness dimensions. Grinding is always performed on rim face, W dimension.
Limitation: Minimum back thickness, E dimension, should not be less than one-fourth T dimension. In addition, when unthreaded hole wheels are specified, the inside flat, K dimension, must be large enough to accommodate a suitable flange.
Type 6 Straight Cup Wheels
Type 6—Straight Cup Wheel
Side grinding wheel having a diameter, thickness and hole with one side straight or flat and the opposite side recessed. This type, however, differs from Type 5 in that the grinding is performed on the wall of the abrasive created by the difference between the diameter of the recess and the outside diameter of the wheel. Therefore, the wall dimension “W” takes precedence over the diameter of the recess as an essential intermediate dimension to describe this shape type.
Type 1 straight wheels have diameter, thickness, and hole size dimensions and should be used only on the periphery. Type 1 wheels shall be mounted between flanges.
Limitation: Hole dimension (H) should not be greater than two-thirds of wheel diameter dimension (D) for precision, cylindrical, centerless, or surface grinding applications. Maximum hole size for all other applications should not exceed one-half wheel diameter.
Type 1 Straight Wheels
Type 1—Straight Wheel
Peripheral grinding wheel having a diameter, thickness and hole.
A jack is an appliance for lifting and lowering or moving horizontally a load by application of a pushing force.
The rating of a jack is the maximum working load for which it is designed to lift safely that load throughout its specified amount of travel.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49750, Oct. 24, 1978]
Each employer shall be responsible for the safe condition of tools and equipment used by employees, including tools and equipment which may be furnished by employees.
Compressed air shall not be used for cleaning purposes except where reduced to less than 30 p.s.i. and then only with effective chip guarding and personal protective equipment.
Belt sanding machines shall be provided with guards at each nip point where the sanding belt runs onto a pulley. These guards shall effectively prevent the hands or fingers of the operator from coming in contact with the nip points. The unused run of the sanding belt shall be guarded against accidental contact.
All cracked saws shall be removed from service.
Portable electric powered tools shall meet the electrical requirements of subpart S of this part.
A tool retainer shall be installed on each piece of utilization equipment which, without such a retainer, may eject the tool.
Hose and hose connections used for conducting compressed air to utilization equipment shall be designed for the pressure and service to which they are subjected.
Abrasive wheels shall be used only on machine provided with safety guards as defined in paragraph (c) (1) through (4) of this section.
The requirements of this paragraph (c)(1) shall not apply to the following classes of wheels and conditions.
Safety guards on all operations where the work provides a suitable measure of protection to the operator may be so constructed that the spindle end, nut and outer flange are exposed. Where the nature of the work is such as to entirely cover the side of the wheel, the side covers of the guard may be omitted.
The spindle end, nut, and outer flange may be exposed on portable machines designed for, and used with, type 6, 11, 27, and 28 abrasive wheels, cutting off wheels, and tuck pointing wheels.
Cup wheels (Types 6 and 11) shall be protected by:
Safety guards used on machines known as right angle head or vertical portable grinders shall have a maximum exposure angle of 180°, and the guard shall be so located so as to be between the operator and the wheel during use. Adjustment of guard shall be such that pieces of an accidentally broken wheel will be deflected away from the operator. (See Figure P-4.)
Natural sandstone wheels and metal, wooden, cloth, or paper discs, having a layer of abrasive on the surface are not covered by this paragraph.
Tools of this type shall have the characteristics outlined in ( a ) through ( h ) of this section.
Be sure the operating control(s) is in neutral before starting the engine,” or similar wording shall be clearly visible at an engine starting control point on self-propelled mowers.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49750, Oct. 24, 1978; 49 FR 5323, Feb. 10, 1984; 50 FR 4649, Feb. 1, 1985; 61 FR 9240, Mar. 7, 1996; 70 FR 53929, Sept. 13, 2005; 72 FR 71070, Dec. 14, 2007]
The blast cleaning nozzles shall be equipped with an operating valve which must be held open manually. A support shall be provided on which the nozzle may be mounted when it is not in use.
[39 FR 23502, June 27, 1974, as amended at 49 FR 5323, Feb. 10, 1984]
As used in this subpart:
[55 FR 13696, Apr. 11, 1990, as amended at 61 FR 9240, Mar. 7, 1996; 72 FR 71070, Dec. 14, 2007]
For elaboration of these basic precautions and of the special precautions of paragraph (a)(2) of this section as well as a delineation of the fire protection and prevention responsibilities of welders and cutters, their supervisors (including outside contractors) and those in management on whose property cutting and welding is to be performed, see Standard for Fire Prevention in Use of Cutting and Welding Processes, NFPA Standard 51B, 1962, which is incorporated by reference as specified in § 1910.6. The basic precautions for fire prevention in welding or cutting work are:
If the object to be welded or cut cannot readily be moved, all movable fire hazards in the vicinity shall be taken to a safe place.
If the object to be welded or cut cannot be moved and if all the fire hazards cannot be removed, then guards shall be used to confine the heat, sparks, and slag, and to protect the immovable fire hazards.
If the requirements stated in paragraphs (a)(1)(i) and (a)(1)(ii) of this section cannot be followed then welding and cutting shall not be performed.
When the nature of the work to be performed falls within the scope of paragraph (a)(1)(ii) of this section certain additional precautions may be necessary:
Wherever there are floor openings or cracks in the flooring that cannot be closed, precautions shall be taken so that no readily combustible materials on the floor below will be exposed to sparks which might drop through the floor. The same precautions shall be observed with regard to cracks or holes in walls, open doorways and open or broken windows.
Suitable fire extinguishing equipment shall be maintained in a state of readiness for instant use. Such equipment may consist of pails of water, buckets of sand, hose or portable extinguishers depending upon the nature and quantity of the combustible material exposed.
Before cutting or welding is permitted, the area shall be inspected by the individual responsible for authorizing cutting and welding operations. He shall designate precautions to be followed in granting authorization to proceed preferably in the form of a written permit.
Where combustible materials such as paper clippings, wood shavings, or textile fibers are on the floor, the floor shall be swept clean for a radius of 35 feet (10.7 m). Combustible floors shall be kept wet, covered with damp sand, or protected by fire-resistant shields. Where floors have been wet down, personnel operating arc welding or cutting equipment shall be protected from possible shock.
Cutting or welding shall not be permitted in the following situations:
Where practicable, all combustibles shall be relocated at least 35 feet (10.7 m) from the work site. Where relocation is impracticable, combustibles shall be protected with flameproofed covers or otherwise shielded with metal or asbestos guards or curtains.
Ducts and conveyor systems that might carry sparks to distant combustibles shall be suitably protected or shut down.
Where cutting or welding is done near walls, partitions, ceiling or roof of combustible construction, fire-resistant shields or guards shall be provided to prevent ignition.
If welding is to be done on a metal wall, partition, ceiling or roof, precautions shall be taken to prevent ignition of combustibles on the other side, due to conduction or radiation, preferably by relocating combustibles. Where combustibles are not relocated, a fire watch on the opposite side from the work shall be provided.
Welding shall not be attempted on a metal partition, wall, ceiling or roof having a combustible covering nor on walls or partitions of combustible sandwich-type panel construction.
Cutting or welding on pipes or other metal in contact with combustible walls, partitions, ceilings or roofs shall not be undertaken if the work is close enough to cause ignition by conduction.
Management shall recognize its responsibility for the safe usage of cutting and welding equipment on its property and:
The Supervisor:
Cutting or welding shall be permitted only in areas that are or have been made fire safe. When work cannot be moved practically, as in most construction work, the area shall be made safe by removing combustibles or protecting combustibles from ignition sources.
No welding, cutting, or other hot work shall be performed on used drums, barrels, tanks or other containers until they have been cleaned so thoroughly as to make absolutely certain that there are no flammable materials present or any substances such as greases, tars, acids, or other materials which when subjected to heat, might produce flammable or toxic vapors. Any pipe lines or connections to the drum or vessel shall be disconnected or blanked.
All hollow spaces, cavities or containers shall be vented to permit the escape of air or gases before preheating, cutting or welding. Purging with inert gas is recommended.
When arc welding is to be suspended for any substantial period of time, such as during lunch or overnight, all electrodes shall be removed from the holders and the holders carefully located so that accidental contact cannot occur and the machine be disconnected from the power source.
In order to eliminate the possibility of gas escaping through leaks or improperly closed valves, when gas welding or cutting, the torch valves shall be closed and the gas supply to the torch positively shut off at some point outside the confined area whenever the torch is not to be used for a substantial period of time, such as during lunch hour or overnight. Where practicable, the torch and hose shall also be removed from the confined space.
A welder or helper working on platforms, scaffolds, or runways shall be protected against falling. This may be accomplished by the use of railings, safety belts, life lines, or some other equally effective safeguards.
Welders shall place welding cable and other equipment so that it is clear of passageways, ladders, and stairways.
| Welding operation | Shade No. |
|---|---|
| Shielded metal-arc welding— 1 ⁄ 16 -, 3 ⁄ 32 -, 1 ⁄ 8 -, 5 ⁄ 32 -inch electrodes | 10 |
| Gas-shielded arc welding (nonferrous)— 1 ⁄ 16 -, 3 ⁄ 32 -, 1 ⁄ 8 -, 5 ⁄ 32 -inch electrodes | 11 |
| Gas-shielded arc welding (ferrous)— 1 ⁄ 16 -, 3 ⁄ 32 -, 1 ⁄ 8 -, 5 ⁄ 32 -inch electrodes | 12 |
| Shielded metal-arc welding: | |
| 3 ⁄ 16 -, 7 ⁄ 32 -, 1 ⁄ 4 -inch electrodes | 12 |
| 5 ⁄ 16 -, 3 ⁄ 8 -inch electrodes | 14 |
| Atomic hydrogen welding | 10-14 |
| Carbon arc welding | 14 |
| Soldering | 2 |
| Torch brazing | 3 or 4 |
| Light cutting, up to 1 inch | 3 or 4 |
| Medium cutting, 1 inch to 6 inches | 4 or 5 |
| Heavy cutting, 6 inches and over | 5 or 6 |
| Gas welding (light) up to 1 ⁄ 8 inch | 4 or 5 |
| Gas welding (medium) 1 ⁄ 8 inch to 1 ⁄ 2 inch | 5 or 6 |
| Gas welding (heavy) 1 ⁄ 2 inch and over | 6 or 8 |
| Note: In gas welding or oxygen cutting where the torch produces a high yellow light, it is desirable to use a filter or lens that absorbs the yellow or sodium line in the visible light of the operation. |
Where the work permits, the welder should be enclosed in an individual booth painted with a finish of low reflectivity such as zinc oxide (an important factor for absorbing ultraviolet radiations) and lamp black, or shall be enclosed with noncombustible screens similarly painted. Booths and screens shall permit circulation of air at floor level. Workers or other persons adjacent to the welding areas shall be protected from the rays by noncombustible or flameproof screens or shields or shall be required to wear appropriate goggles.
Employees exposed to the hazards created by welding, cutting, or brazing operations shall be protected by personal protective equipment in accordance with the requirements of § 1910.132 of this part. Appropriate protective clothing required for any welding operation will vary with the size, nature and location of the work to be performed.
As used herein confined space is intended to mean a relatively small or restricted space such as a tank, boiler, pressure vessel, or small compartment of a ship.
Ventilation is a prerequisite to work in confined spaces. For ventilation requirements see paragraph (c) of this section.
When welding or cutting is being performed in any confined spaces the gas cylinders and welding machines shall be left on the outside. Before operations are started, heavy portable equipment mounted on wheels shall be securely blocked to prevent accidental movement.
Where a welder must enter a confined space through a manhole or other small opening, means shall be provided for quickly removing him in case of emergency. When safety belts and lifelines are used for this purpose they shall be so attached to the welder's body that his body cannot be jammed in a small exit opening. An attendant with a preplanned rescue procedure shall be stationed outside to observe the welder at all times and be capable of putting rescue operations into effect.
When arc welding is to be suspended for any substantial period of time, such as during lunch or overnight, all electrodes shall be removed from the holders and the holders carefully located so that accidental contact cannot occur and the machine disconnected from the power source.
In order to eliminate the possibility of gas escaping through leaks of improperly closed valves, when gas welding or cutting, the torch valves shall be closed and the fuel-gas and oxygen supply to the torch positively shut off at some point outside the confined area whenever the torch is not to be used for a substantial period of time, such as during lunch hour or overnight. Where practicable the torch and hose shall also be removed from the confined space.
After welding operations are completed, the welder shall mark the hot metal or provide some other means of warning other workers.
The requirements in this paragraph have been established on the basis of the following three factors in arc and gas welding which govern the amount of contamination to which welders may be exposed:
When welding must be performed in a space entirely screened on all sides, the screens shall be so arranged that no serious restriction of ventilation exists. It is desirable to have the screens so mounted that they are about 2 feet (0.61 m) above the floor unless the work is performed at so low a level that the screen must be extended nearer to the floor to protect nearby workers from the glare of welding.
Local exhaust or general ventilating systems shall be provided and arranged to keep the amount of toxic fumes, gases, or dusts below the maximum allowable concentration as specified in § 1910.1000 of this part.
The employer shall include the potentially hazardous materials employed in fluxes, coatings, coverings, and filler metals, all of which are potentially used in welding and cutting, or are released to the atmosphere during welding and cutting, in the program established to comply with the Hazard Communication Standard (HCS) (§ 1910.1200). The employer shall ensure that each employee has access to labels on containers of such materials and safety data sheets, and is trained in accordance with the provisions of § 1910.1200. Potentially hazardous materials shall include but not be limited to the materials itemized in paragraphs (c)(5) through (c)(12) of this section.
Do not use in areas without adequate ventilation. See ANSI Z49.1-1967 Safety in Welding, Cutting, and Allied Processes published by the American Welding Society.
CAUTION
Welding may produce fumes and gases hazardous to health. Avoid breathing these fumes and gases. Use adequate ventilation. See ANSI Z49.1-1967 Safety in Welding and Cutting published by the American Welding Society.
WARNING
CONTAINS CADMIUM—POISONOUS FUMES MAY BE FORMED ON HEATING
Do not breathe fumes. Use only with adequate ventilation such as fume collectors, exhaust ventilators, or air-supplied respirators. See ANSI Z49.1-1967. If chest pain, cough, or fever develops after use call physician immediately.
CAUTION
CONTAINS FLUORIDES
This flux when heated gives off fumes that may irritate eyes, nose and throat.
1. Avoid fumes—use only in well-ventilated spaces.
2. Avoid contact of flux with eyes or skin.
3. Do not take internally.
Mechanical ventilation shall be provided when welding or cutting is done on metals not covered in paragraphs (c)(5) through (c)(12) of this section. (For specific materials, see the ventilation requirements of paragraphs (c)(5) through (c)(12) of this section.)
Such ventilation shall be at the minimum rate of 2,000 cubic feet (57 m 3 ) per minute per welder, except where local exhaust hoods and booths as per paragraph (c)(3) of this section, or airline respirators approved by the Mine Safety and Health Administration and the National Institute for Occupational Safety and Health, pursuant to the provisions of 30 CFR part 11, are provided. Natural ventilation is considered sufficient for welding or cutting operations where the restrictions in paragraph (c)(2)(i) of this section are not present.
Mechanical local exhaust ventilation may be by means of either of the following:
Freely movable hoods intended to be placed by the welder as near as practicable to the work being welded and provided with a rate of air-flow sufficient to maintain a velocity in the direction of the hood of 100 linear feet (30 m) per minute in the zone of welding when the hood is at its most remote distance from the point of welding. The rates of ventilation required to accomplish this control velocity using a 3-inch (7.6 cm) wide flanged suction opening are shown in the following table:
| Welding zone | Minimum air flow 1 cubic feet/minute | Duct diameter, inches 2 |
|---|---|---|
| 4 to 6 inches from arc or torch | 150 | 3 |
| 6 to 8 inches from arc or torch | 275 | 3 1 ⁄ 2 |
| 8 to 10 inches from arc or torch | 425 | 4 1 ⁄ 2 |
| 10 to 12 inches from arc or torch | 600 | 5 1 ⁄ 2 |
| 1 When brazing with cadmium bearing materials or when cutting on such materials increased rates of ventilation may be required. | ||
| 2 Nearest half-inch duct diameter based on 4,000 feet per minute velocity in pipe. |
A fixed enclosure with a top and not less than two sides which surround the welding or cutting operations and with a rate of airflow sufficient to maintain a velocity away from the welder of not less than 100 linear feet (30 m) per minute.
All welding and cutting operations carried on in confined spaces shall be adequately ventilated to prevent the accumulation of toxic materials or possible oxygen deficiency. This applies not only to the welder but also to helpers and other personnel in the immediate vicinity. All air replacing that withdrawn shall be clean and respirable.
In circumstances for which it is impossible to provide such ventilation, airline respirators or hose masks approved for this purpose by the National Institute for Occupational Safety and Health (NIOSH) under 42 CFR part 84 must be used.
In areas immediately hazardous to life, a full-facepiece, pressure-demand, self-contained breathing apparatus or a combination full-facepiece, pressure-demand supplied-air respirator with an auxiliary, self-contained air supply approved by NIOSH under 42 CFR part 84 must be used.
Where welding operations are carried on in confined spaces and where welders and helpers are provided with hose masks, hose masks with blowers or self-contained breathing equipment approved by the Mine Safety and Health Administration and the National Institute for Occupational Safety and Health, a worker shall be stationed on the outside of such confined spaces to insure the safety of those working within.
Oxygen shall never be used for ventilation.
In confined spaces, welding or cutting involving fluxes, coverings, or other materials which contain fluorine compounds shall be done in accordance with paragraph (c)(4) of this section. A fluorine compound is one that contains fluorine, as an element in chemical combination, not as a free gas.
The need for local exhaust ventilation or airline respirators for welding or cutting in other than confined spaces will depend upon the individual circumstances. However, experience has shown such protection to be desirable for fixed-location production welding and for all production welding on stainless steels. Where air samples taken at the welding location indicate that the fluorides liberated are below the maximum allowable concentration, such protection is not necessary.
In confined spaces welding or cutting involving zinc-bearing base or filler metals or metals coated with zinc-bearing materials shall be done in accordance with paragraph (c)(4) of this section.
Indoors, welding or cutting involving zinc-bearing base or filler metals coated with zinc-bearing materials shall be done in accordance with paragraph (c)(3) of this section.
In confined spaces, welding involving lead-base metals (erroneously called lead-burning) shall be done in accordance with paragraph (c)(4) of this section.
Indoors, welding involving lead-base metals shall be done in accordance with paragraph (c)(3) of this section.
In confined spaces or indoors, welding or cutting operations involving metals containing lead, other than as an impurity, or metals coated with lead-bearing materials, including paint, must be done using local exhaust ventilation or airline respirators. Such operations, when done outdoors, must be done using respirators approved for this purpose by NIOSH under 42 CFR part 84. In all cases, workers in the immediate vicinity of the cutting operation must be protected by local exhaust ventilation or airline respirators.
Welding or cutting indoors, outdoors, or in confined spaces involving beryllium-containing base or filler metals shall be done using local exhaust ventilation and airline respirators unless atmospheric tests under the most adverse conditions have established that the workers' exposure is within the acceptable concentrations defined by § 1910.1000 of this part. In all cases, workers in the immediate vicinity of the welding or cutting operations shall be protected as necessary by local exhaust ventilation or airline respirators.
In confined spaces or indoors, welding or cutting operations involving cadmium-bearing or cadmium-coated base metals must be done using local exhaust ventilation or airline respirators unless atmospheric tests under the most adverse conditions show that employee exposure is within the acceptable concentrations specified by 29 CFR 1910.1000. Such operations, when done outdoors, must be done using respirators, such as fume respirators, approved for this purpose by NIOSH under 42 CFR part 84.
Welding (brazing) involving cadmium-bearing filler metals shall be done using ventilation as prescribed in paragraph (c)(3) or (c)(4) of this section if the work is to be done in a confined space.
In confined spaces or indoors, welding or cutting operations involving metals coated with mercury-bearing materials, including paint, must be done using local exhaust ventilation or airline respirators unless atmospheric tests under the most adverse conditions show that employee exposure is within the acceptable concentrations specified by 29 CFR 1910.1000. Such operations, when done outdoors, must be done using respirators approved for this purpose by NIOSH under 42 CFR part 84.
In the use of cleaning materials, because of their possible toxicity or flammability, appropriate precautions such as manufacturers instructions shall be followed.
Degreasing and other cleaning operations involving chlorinated hydrocarbons shall be so located that no vapors from these operations will reach or be drawn into the atmosphere surrounding any welding operation. In addition, trichloroethylene and perchlorethylene should be kept out of atmospheres penetrated by the ultraviolet radiation of gas-shielded welding operations.
Oxygen cutting, using either a chemical flux or iron powder or gas-shielded arc cutting of stainless steel, shall be done using mechanical ventilation adequate to remove the fumes generated.
First-aid equipment shall be available at all times. All injuries shall be reported as soon as possible for medical attention. First aid shall be rendered until medical attention can be provided.
The requirements of paragraphs (b) and (c) of this section and § 1910.254 of this part shall be observed.
Where field shop operations are involved for fabrication of fittings, river crossings, road crossings, and pumping and compressor stations the requirements of paragraphs (a), (b), and (c) of this section and §§ 1910.253 and 1910.254 of this part shall be observed.
When arc welding is performed in wet conditions, or under conditions of high humidity, special protection against electric shock shall be supplied.
In pressure testing of pipelines, the workers and the public shall be protected against injury by the blowing out of closures or other pressure restraining devices. Also, protection shall be provided against expulsion of loose dirt that may have become trapped in the pipe.
The welded construction of transmission pipelines shall be conducted in accordance with the Standard for Welding Pipe Lines and Related Facilities, API Std. 1104—1968, which is incorporated by reference as specified in § 1910.6.
The connection, by welding, of branches to pipelines carrying flammable substances shall be performed in accordance with Welding or Hot Tapping on Equipment Containing Flammables, API Std. PSD No. 2201—1963, which is incorporated by reference as specified in § 1910.6.
The use of X-rays and radioactive isotopes for the inspection of welded pipeline joints shall be carried out in conformance with the American National Standard Safety Standard for Non-Medical X-ray and Sealed Gamma-Ray Sources, ANSI Z54.1—1963, which is incorporated by reference as specified in § 1910.6.
The requirements of paragraphs (a), (b), and (c) of this section and §§ 1910.253 and 1910.254 of this part shall be observed.
The use of X-rays and radioactive isotopes for the inspection of welded piping joints shall be in conformance with the American National Standard Safety Standard for Non-Medical X-ray and Sealed Gamma-Ray Sources, ANSI Z54.1—1963.
[55 FR 13696, Apr. 11, 1990, as amended at 61 FR 9240, Mar. 7, 1996; 63 FR 1284, Jan. 8, 1998; 74 FR 46357, Sept. 9, 2009; 77 FR 17777, Mar. 26, 2012]
Mixtures of fuel gases and air or oxygen may be explosive and shall be guarded against. No device or attachment facilitating or permitting mixtures of air or oxygen with flammable gases prior to consumption, except at the burner or in a standard torch, shall be allowed unless approved for the purpose.
Under no condition shall acetylene be generated, piped (except in approved cylinder manifolds) or utilized at a pressure in excess of 15 psig (103 kPa gauge pressure) or 30 psia (206 kPa absolute). The 30 psia (206 kPa absolute) limit is intended to prevent unsafe use of acetylene in pressurized chambers such as caissons, underground excavations or tunnel construction.) This requirement is not intended to apply to storage of acetylene dissolved in a suitable solvent in cylinders manufactured and maintained according to U.S. Department of Transportation requirements, or to acetylene for chemical use. The use of liquid acetylene shall be prohibited.
Only approved apparatus such as torches, regulators or pressure-reducing valves, acetylene generators, and manifolds shall be used.
Workmen in charge of the oxygen or fuel-gas supply equipment, including generators, and oxygen or fuel-gas distribution piping systems shall be instructed and judged competent by their employers for this important work before being left in charge. Rules and instructions covering the operation and maintenance of oxygen or fuel-gas supply equipment including generators, and oxygen or fuel-gas distribution piping systems shall be readily available.
Inside a building, cylinders, except those in actual use or attached ready for use, shall be limited to a total gas capacity of 2,000 cubic feet (56 m 3 ) or 300 pounds (135.9 kg) of liquefied petroleum gas.
Low-Pressure Manifold
Do Not Connect High-Pressure Cylinders
Maximum Pressure—250 psig (1.7 MPa)
Equipment shall be installed and used only in the service for which it is approved and as recommended by the manufacturer.
Service piping systems shall be protected by pressure relief devices set to function at not more than the design pressure of the systems and discharging upwards to a safe location.
The space around the generator shall be ample for free, unobstructed operation and maintenance and shall permit ready adjustment and charging.
Metal tools, even the so-called spark resistant type may cause ignition of an acetylene and air mixture when opening carbide containers.
[55 FR 13696, Apr. 11, 1990, as amended at 55 FR 32015, Aug. 6, 1990; 55 FR 46053, Nov. 1, 1990; 61 FR 9241, Mar. 7, 1996; 72 FR 71070, Dec. 14, 2007]
Welding equipment shall be chosen for safe application to the work to be done as specified in paragraph (b) of this section.
Welding equipment shall be installed safely as specified by paragraph (c) of this section.
Workmen designated to operate arc welding equipment shall have been properly instructed and qualified to operate such equipment as specified in paragraph (d) of this section.
Assurance of consideration of safety in design is obtainable by choosing apparatus complying with the Requirements for Electric Arc-Welding Apparatus, NEMA EW-1-1962, National Electrical Manufacturers Association or the Safety Standard for Transformer-Type Arc-Welding Machines, ANSI C33.2—1956, Underwriters' Laboratories, both of which are incorporated by reference as specified in § 1910.6.
The following limits shall not be exceeded:
welding under wet conditions or warm surroundings where perspiration is a factor, the use of reliable automatic controls for reducing no load voltage is recommended to reduce the shock hazard.
reactors shall not be used to draw welding current directly from any a.c. power source having a voltage exceeding 80 volts.
Installation including power supply shall be in accordance with the requirements of subpart S of this part.
machines shall be connected with the same polarity.
machines shall be connected to the same phase of the supply circuit and with the same instantaneous polarity.
Workers assigned to operate or maintain arc welding equipment shall be acquainted with the requirements of this section and with 1910.252 (a), (b), and (c) of this part.
Before starting operations all connections to the machine shall be checked to make certain they are properly made. The work lead shall be firmly attached to the work; magnetic work clamps shall be freed from adherent metal particles of spatter on contact surfaces. Coiled welding cable shall be spread out before use to avoid serious overheating and damage to insulation.
Grounding of the welding machine frame shall be checked. Special attention shall be given to safety ground connections of portable machines.
There shall be no leaks of cooling water, shielding gas or engine fuel.
It shall be determined that proper switching equipment for shutting down the machine is provided.
Printed rules and instructions covering operation of equipment supplied by the manufacturers shall be strictly followed.
Electrode holders when not in use shall be so placed that they cannot make electrical contact with persons, conducting objects, fuel or compressed gas tanks.
Cables with splices within 10 feet (3 m) of the holder shall not be used. The welder should not coil or loop welding electrode cable around parts of his body.
[55 FR 13696, Apr. 11, 1990, as amended at 61 FR 9241, Mar. 7, 1996; 70 FR 53929, Sept. 13, 2005]
All equipment shall be installed by a qualified electrician in conformance with subpart S of this part. There shall be a safety-type disconnecting switch or a circuit breaker or circuit interrupter to open each power circuit to the machine, conveniently located at or near the machine, so that the power can be shut off when the machine or its controls are to be serviced.
Ignitron tubes used in resistance welding equipment shall be equipped with a thermal protection switch.
Workmen designated to operate resistance welding equipment shall have been properly instructed and judged competent to operate such equipment.
Controls of all automatic or air and hydraulic clamps shall be arranged or guarded to prevent the operator from accidentally activating them.
All external weld initiating control circuits shall operate on low voltage, not over 120 volts, for the safety of the operators.
Stored energy or capacitor discharge type of resistance welding equipment and control panels involving high voltage (over 550 volts) shall be suitably insulated and protected by complete enclosures, all doors of which shall be provided with suitable interlocks and contacts wired into the control circuit (similar to elevator interlocks). Such interlocks or contacts shall be so designed as to effectively interrupt power and short circuit all capacitors when the door or panel is open. A manually operated switch or suitable positive device shall be installed, in addition to the mechanical interlocks or contacts, as an added safety measure assuring absolute discharge of all capacitors.
All doors and access panels of all resistance welding machines and control panels shall be kept locked and interlocked to prevent access, by unauthorized persons, to live portions of the equipment.
All press welding machine operations, where there is a possibility of the operator's fingers being under the point of operation, shall be effectively guarded by the use of a device such as an electronic eye safety circuit, two hand controls or protection similar to that prescribed for punch press operation, § 1910.217 of this part. All chains, gears, operating bus linkage, and belts shall be protected by adequate guards, in accordance with § 1910.219 of this part.
The hazard of flying sparks shall be, wherever practical, eliminated by installing a shield guard of safety glass or suitable fire-resistant plastic at the point of operation. Additional shields or curtains shall be installed as necessary to protect passing persons from flying sparks. (See § 1910.252(b)(2)(i)(C) of this part.)
All foot switches shall be guarded to prevent accidental operation of the machine.
Two or more safety emergency stop buttons shall be provided on all special multispot welding machines, including 2-post and 4-post weld presses.
On large machines, four safety pins with plugs and receptacles (one in each corner) shall be provided so that when safety pins are removed and inserted in the ram or platen, the press becomes inoperative.
Where technically practical, the secondary of all welding transformers used in multispot, projection and seam welding machines shall be grounded. This may be done by permanently grounding one side of the welding secondary current circuit. Where not technically practical, a center tapped grounding reactor connected across the secondary or the use of a safety disconnect switch in conjunction with the welding control are acceptable alternates. Safety disconnect shall be arranged to open both sides of the line when welding current is not present.
All portable welding guns shall have suitable counterbalanced devices for supporting the guns, including cables, unless the design of the gun or fixture makes counterbalancing impractical or unnecessary.
All portable welding guns, transformers and related equipment that is suspended from overhead structures, eye beams, trolleys, etc., shall be equipped with safety chains or cables. Safety chains or cables shall be capable of supporting the total shock load in the event of failure of any component of the supporting system.
Each clevis shall be capable of supporting the total shock load of the suspended equipment in the event of trolley failure.
All initiating switches, including retraction and dual schedule switches, located on the portable welding gun shall be equipped with suitable guards capable of preventing accidental initiation through contact with fixturing, operator's clothing, etc. Initiating switch voltage shall not exceed 24 volts.
The movable holder, where it enters the gun frame, shall have sufficient clearance to prevent the shearing of fingers carelessly placed on the operating movable holder.
The secondary and case of all portable welding transformers shall be grounded. Secondary grounding may be by center tapped secondary or by a center tapped grounding reactor connected across the secondary.
Flash welding machines shall be equipped with a hood to control flying flash. In cases of high production, where materials may contain a film of oil and where toxic elements and metal fumes are given off, ventilation shall be provided in accordance with § 1910.252(c) of this part.
For the protection of the operators of nearby equipment, fire-resistant curtains or suitable shields shall be set up around the machine and in such a manner that the operators movements are not hampered.
Periodic inspection shall be made by qualified maintenance personnel, and a certification record maintained. The certification record shall include the date of inspection, the signature of the person who performed the inspection and the serial number, or other identifier, for the equipment inspected. The operator shall be instructed to report any equipment defects to his supervisor and the use of the equipment shall be discontinued until safety repairs have been completed.
This section applies to establishments where pulp, paper, and paperboard are manufactured and converted. This section does not apply to logging and the transportation of logs to pulp, paper, and paperboard mills.
Standards covering issues of occupational safety and health which have general application without regard to any specific industry are incorporated by reference in paragraphs (b) through (m) of this section and in subparagraphs (3) and (4) of this paragraph and made applicable under this section. Such standards shall be construed according to the rules set forth in § 1910.5.
Establishments subject to this section shall comply with the following standards of the American National Standards Institute, which are incorporated by reference as specified in § 1910.6:
The following standards, which are incorporated by reference as specified in § 1910.6, shall be considered standards under this section:
Boiler and Pressure Vessel Code, Section VIII, Unfired Pressure Vessels, including addenda 1969.
17, July 1960, Institute of Makers of Explosives.
Devices such as padlocks shall be provided for locking out the source of power at the main disconnect switch. Before any maintenance, inspection, cleaning, adjusting, or servicing of equipment (electrical, mechanical, or other) that requires entrance into or close contact with the machinery or equipment, the main power disconnect switch or valve, or both, controlling its source of power or flow of material, shall be locked out or blocked off with padlock, blank flange, or similar device.
Emergency lighting shall be provided wherever it is necessary for employees to remain at their machines or stations to shut down equipment in case of power failure. Emergency lighting shall be provided at stairways and passageways or aisleways used by employees for emergency exit in case of power failure. Emergency lighting shall be provided in all plant first aid and medical facilities.
Where large forklift trucks, or lift trucks with clam-jaws, are used in the yard, the operator's enclosed cab shall be provided with an escape hatch, whenever the hydraulic arm blocks escape through the side doors.
All cars shall be securely fastened in place and all employees in the clear before dumping is started.
All trucks and trailers shall be securely fastened in place and all employees in the clear before dumping is started.
Artificial illumination shall be provided when loading or unloading is performed after dark, in accordance with American National Standard A11.1—1965 (R—1970).
When barking drums are employed in the yard, the requirements of paragraph (e)(12) of this section shall apply.
Handles of wood hooks shall be locked to the shank to prevent them from rotating.
When conveyors cross walkways or roadways in the yards, the employer must erect signs reading “Danger—Overhead Conveyor” or an equivalent warning, in accordance with ANSI Z35.1-1968 or ANSI Z535.2-2011, incorporated by reference in § 1910.6.
Whenever possible, all dust, fumes, and gases incident to handling materials shall be controlled at the source, in accordance with American National Standard Z9.2—1960. Where control at the source is not possible, respirators with goggles or protective masks shall be provided, and employees shall wear them when handling alum, clay, soda ash, lime, bleach powder, sulfur, chlorine, and similar materials, and when opening rag bales.
A guard shall be provided in front of all gang and slasher saws to protect workers from wood thrown by saws. A guard shall be placed over tail sprockets.
Saws shall be stopped and power switches shall be locked out and tagged whenever it is necessary for any person to be on the slasher table.
The runway from the pond or unloading dock to the table shall be protected with standard handrails and toeboards. Inclined portions shall have cleats or equivalent nonslip surfacing that complies with subpart D of this part. Protective equipment shall be provided for persons working over water.
Where not protected by the frame of the machine, the underside of the slasher saws shall be enclosed with guards.
The requirements of paragraph (c)(15)(iv) of this section shall apply.
Each barker shall be equipped with a feed and turnover device which will make it unnecessary for the operator to hold a bolt or log by hand during the barking operation. Eye, ear, and head protection shall be provided for the operator, in accordance with paragraph (b)(2) of this section.
All control devices shall be locked out and tagged when knives are being changed.
Water wheels, when directly connected to barker disks or grinders, shall be provided with speed governors, if operated with gate wide open.
In addition to motor switch, clutch, belt shifter, or other power disconnecting device, intermittent barking drums shall be equipped with a device which may be locked to prevent the drum from moving while it is being emptied or filled.
Hydraulic barkers shall be enclosed with strong baffles at the inlet and the outlet. The operator shall be protected by at least five-ply laminated glass.
The block upon or against which the wood is rested shall have a corrugated surface or other means provided that the wood will not slip. Wood to be split, and also the splitting block, shall be free of ice, snow, or chips. The operator shall be provided with eye and foot protection. A clear and unobstructed view shall be maintained between equipment and workers around the block and the workers' help area.
Power for the operation of the splitter shall be controlled by a clutch or equivalent device.
The operators of knot cleaners of the woodpecker type shall wear eye protection equipment.
The feed system to the chipper spout shall be arranged in such a way that the operator does not stand in a direct line with the chipper spout. All chipper spouts shall be enclosed to a height of at least 42 inches from the floor or operator's platform. When other protection is not sufficient, the operator shall wear a safety belt line. The safety belt line shall be fastened in such a manner as to make it impossible for the operator to fall into the throat of the chipper. Ear protection equipment shall be worn by the operator and others in the immediate area if there is any possibility that the noise level may be harmful (see § 1910.95).
Carriers shall be provided and used for transportation of knives.
Conveyors and conveyor drive belts and pulleys shall be fully enclosed or, if open and within 7 feet of the floor, shall be constructed and guarded in accordance with paragraph (c)(15) of this section and American National Standards B15.1—1953 (Reaffirmed 1958) and B20.1—1957.
Measures for the control of dust shall be provided, in accordance with American National Standards Z33.1—1961, Z87.1—1968, and Z88.2—1969.
Outside elevators shall be inspected daily during winter months when ice materially affects safety. Elevators, runways, stairs, etc., for the acid tower shall be inspected monthly for defects that may occur because of exposure to acid or corrosive gases.
Where lime slaking takes place, employees shall be provided with rubber boots, rubber gloves, protective aprons, and eye protection. A deluge shower and eye fountain shall be provided to flush the skin and eyes to counteract lime or acid burns.
When lead burning is being done within tanks, fresh air shall be forced into the tanks so that fresh air will reach the face of the worker first and the direction of the current will never be from the source of the fumes toward the face of the workers. Supplied air respirators (constant-flow type) shall be provided.
Hoops of tanks shall be made of rods rather than flat strips and shall be safely maintained by scheduled inspections.
Steam or compressed-air lances, or other facilities, shall be used for breaking down the arches caused by jamming in chip lofts. No worker shall be permitted to enter a bin unless provided with a safety belt, with line attached, and an attendant stationed at the bin to summon assistance.
At least one unobstructed exit at each end of the room shall be provided on each floor of a digester building.
Gas masks must be available, and they must furnish adequate protection against sulfurous acid and chlorine gases and be inspected and repaired in accordance with 29 CFR 1910.134.
Insofar as the processes of the sulfate and soda operations are similar to those of the sulfite processes, the standard of paragraphs (g) (1) through (17) of this section shall apply.
Exhaust ventilation shall be provided where niter cake is fed into a rotary furnace and shall be so designed and maintained as to keep the concentration of hydrogen sulfide gas below the parts per million listed in § 1910.1000.
All piping leading to tanks shall be blanked off or valved and locked or tagged. Any lines to sewers shall be blanked off to protect workers from air contaminants.
Welding on blow tanks, accumulator tanks, or any other vessels where turpentine vapor or other combustible vapor could gather shall be done only after the vessel has been completely purged of fumes. Fresh air shall be supplied workers inside of vessels.
Nonsparking tools and ground hose shall be used when pumping out the tank. The tank shall be surrounded by a berm or moat.
Bleaching engines, except the Bellmer type, shall be completely covered on the top, with the exception of one small opening large enough to allow filling, but too small to admit an employee. Platforms leading from one engine to another shall have standard guardrails that meet the requirements in subpart D of this part.
Bagged or drummed chemicals require efficient handling to prevent damage and spillage. Certain oxidizing chemicals used in bleaching pulp and also in some sanitizing work require added precautions for safety in storage and handling. In storage, these chemicals must be isolated from combustible materials and other chemicals with which they will react such as acids. They must also be kept dry, clean and uncontaminated.
Hood guards shall be provided on butting saws, in accordance with American National Standard O1.1—1954 (reaffirmed 1961).
The requirements of paragraph (b)(3) of this section shall apply.
Persons exposed to falling material shall wear eye, head, foot, and shin protection equipment, in accordance with American National Standards Z87.1—1968, Z88.2—1969, Z89.1—1969, and Z41.1—1967.
Pulp conveyors and conveyor drive belts and pulleys shall be fully enclosed, or if open and within 7 feet of the floor, shall be constructed and guarded in accordance with American National Standard B20.1—1957.
Paper machines shall be equipped with devices that will stop the machine quickly in an emergency. The devices shall consist of push buttons for electric motive power (or electrically operated engine stops), pull cords connected directly to the prime mover, control clutches, or other devices, interlocked with adequate braking action. The devices shall be tested periodically by making use of them when stopping the machine and shall be so located that any person working on the machine can quickly disconnect the machine from the source of power in case of emergency.
Face shields, aprons, and rubber gloves shall be provided for workmen handling acids in accordance with paragraphs (b)(2) and (d)(1) of this section.
Steps of uniform rise and tread with nonslip surfaces that meet the requirements in subpart D of this part shall be provided at each press.
A removable plank shall be provided along each press, with standard guardrails installed. The planks shall have nonslip surfaces in accordance with paragraph (b)(3) of this section.
If a gear bearing must be oiled while the machine is in operation, an automatic oiling device to protect the oiler shall be provided, or oil cups and grease fittings shall be placed along the walkways out of reach of hot pipes and dryer gears.
All levers carrying weights shall be constructed so that weights will not slip or fall off.
Either a permanent guardrail or apron guard or both shall be installed in front of the first dryer in each section in accordance with paragraph (b)(1) of this section.
All exposed steam and hot-water pipes within 7 feet of the floor or working platform or within 15 inches measured horizontally from stairways, ramps, or fixed ladders shall be covered with an insulating material, or guarded in such manner as to prevent contact.
Dryer gears shall be guarded excepting where the oilers' walkway is removed out of reach of the gears' nips and spokes and hot pipes in accordance with American National Standard B15.1—1953 (reaffirmed 1958).
A feeder belt or other effective device shall be provided for starting paper through the calender stack.
Steps or ladders that comply with subpart D of this part and tread with nonslip surfaces shall be provided at each calendar stack. Handrails and hand grips complying with subpart D shall be provided at each calendar stack.
All exposed sole plates between dryers, calenders, reels, and rewinders shall have a nonskid surface.
The hazard of the nip points on all calender rolls shall be eliminated or minimized by means of an effective barrier device, or by feeding the paper into the rolls by means of a rope carrier, air jets, or hand feeding devices.
[Reserved]
Alloy steel scrapers with pullthrough blades approximately 3 by 5 inches in size shall be used to remove “scabs” from calender rolls.
Permanent lighting shall be installed in all areas where employees are required to make machine adjustments and sheet transfers in accordance with the American National Standard A11.1—1965 (R 1970).
All control panel handles and buttons shall be protected from accidental contact.
Feeder belts, carrier ropes, air carriage, or other equally effective means shall be provided for starting paper into the nip or drum-type reels.
Set screws for securing core collars to winding and unwinding shafts shall not protrude above the face of the collar. All edges of the collar with which an operator's hand comes in contact shall be beveled to remove all sharp corners.
Slitter knives shall be guarded so as to prevent accidental contact. Carriers shall be provided and used for transportation of slitter knives.
The winder shall have a guide rail to align the shaft for easy entrance into the opened rewind shaft bearing housings.
When the core shaft weighs in excess of the safe standard, a mechanical device such as a dolly shall be provided for carrying all or part of the weight when it is being removed from the set of paper and placed in the dressing brackets on the winder.
A nonskid surface shall be provided in the front vicinity of the winder to prevent accidental slipping.
Special standards regarding the use of radiation equipment shall be posted and followed as required by § 1910.96.
Rolls shall be cleaned only on the outrunning side.
Electrically or manually operated quick power disconnecting devices, interlocked with braking action, shall be provided on all operating sides of the machine within easy reach of all employees. These devices shall be tested by making use of them when stopping the machine.
The requirements of paragraph (k)(27) of this section and the American National Standard B15.1—1953 (reaffirmed 1958) shall apply.
These shall be in accordance with American National Standard A17.1—1965.
The requirements of paragraph (k)(22) of this section shall apply.
A zero speed switch should be installed to prevent the guard from being raised while the roll is turning.
The requirements of paragraph (k)(22) of this section shall apply.
The nipping point located on the operator's side shall be guarded by either automatic or manually operated barrier guards interlocked with the drive.
The nip point and cutter knife shall be guarded by either automatic or manually operated barrier guards.
No person shall be permitted to ride on a powered hand truck unless it is so designed by the manufacturer. A limit switch shall be on operating handle—30 degrees each way from a 45-degree angle up and down.
The carton-stitching machine shall be guarded to prevent the operator from coming in contact with the stitching head.
Flag signals, derails, or other protective devices shall be used to protect men during switching operations. The blue flag policy shall be invoked according to paragraph (c)(9)(i) of this section.
[39 FR 23502, June 27, 1974, as amended at 40 FR 23073, May 28, 1975; 43 FR 49751, Oct. 24, 1978; 49 FR 5323, Feb. 10, 1984; 55 FR 32015, Aug. 6, 1990; 61 FR 9241, Mar. 7, 1996; 63 FR 1285, Jan. 8, 1998; 63 FR 33467, June 18, 1998; 72 FR 71070, Dec. 14, 2007; 76 FR 80739, Dec. 27, 2011; 78 FR 35566, June 13, 2013; 81 FR 83005, Nov. 18, 2016]
The requirements of this subpart for textile safety apply to the design, installation, processes, operation, and maintenance of textile machinery, equipment, and other plant facilities in all plants engaged in the manufacture and processing of textiles, except those processes used exclusively in the manufacture of synthetic fibers.
Standards covering issues of occupational safety and health which are of general application without regard to any specific industry are incorporated by reference in paragraphs of this section and made applicable to textiles. All such standards shall be construed according to the rules of construction set out in § 1910.5.
A belt shifter is a device for mechanically shifting a belt from one pulley to another.
A belt shifter lock is a device for positively locking the belt shifter in position while the machine is stopped and the belt is idling on the loose pulleys.
A calender in essence consists of a set of heavy rollers mounted on vertical side frames and arranged to pass cloth between them. Calenders may have two to ten rollers, or bowls, some of which can be heated.
An embossing calender is a calender with two or more rolls, one of which is engraved for producing figured effects of various kinds on a fabric.
Drying cans are hollow cylindrical drums mounted in a frame so they can rotate. They are heated with steam and are used to dry fabrics or yarn as it passes around the perimeter of the can.
Carbonizing means the removing of vegetable matter such as burns, straws, etc., from wool by treatment with acid, followed by heat. The undesired matter is reduced to a carbon-like form which may be removed by dusting or shaking.
A card machine consists of cylinders of various sizes—and in certain cases flats—covered with card clothing and set in relation to each other so that fibers in staple form may be separated into individual relationship. The speed of the cylinders and their direction of rotation varies. The finished product is delivered as a sliver. Cards of different types are: The revolving flat card, the roller-and-clearer card, etc.
Card clothing is the material with which many of the surfaces of a card are covered; e.g., the cylinder, doffer, etc. It consists of a thick foundation material, usually made of textile fabrics, through which are pressed many fine, closely spaced, specially bent wires.
A comber is a machine for combing fibers of cotton, wool, etc. The essential parts are a device for feeding forward a fringe of fibers at regular intervals and an arrangement of combs or pins which, at the right time, pass through the fringe. All tangled fibers, short fibers, and neps are removed and the long fibers are laid parallel.
Combing machinery is a general classification, including combers, sliver lap machines, ribbon lap machines, and gill boxes, but excluding cards.
A rotary staple cutter is a machine consisting of one or more rotary blades used for the purpose of cutting textile fibers into staple lengths.
Exposed to contact shall mean that the location of an object, material, nip point, or point of operation is such that a person is liable to come in contact with it in his normal course of employment.
A Garnett machine means any of a number of types of machines for opening hard twisted waste of wool, cotton, silk, etc. Essentially, such machines consist of a lickerin; one or more cylinders, each having a complement worker and stripper rolls; and a fancy roll and doffer. The action of such machines is somewhat like that of a wool card, but it is much more severe in that the various rolls are covered with garnett wire instead of card clothing.
A gill box is a machine used in the worsted system of manufacturing yarns. Its function is to arrange the fibers in parallel order. Essentially, it consists of a pair of feed rolls and a series of followers where the followers move at a faster surface speed and perform a combing action.
An interlock is a device that operates to prevent the operation of machine while the cover or door of the machine is open or unlocked, and which will also hold the cover or door closed and locked while the machine is in motion.
A dye jig is a machine for dyeing piece goods. The cloth, at full width, passes from a roller through the dye liquor in an open vat and is then wound on another roller. The operation is repeated until the desired shade is obtained.
A kier is a large metal vat, usually a pressure type, in which fabrics may be boiled out, bleached, etc.
A ribbon lapper is a machine used to prepare laps for feeding a cotton comb; its purpose is to provide a uniform lap in which the fibers have been straightened as much as possible.
A sliver lapper is a machine in which a number of parallel card slivers are drafted slightly, laid side by side in a compact sheet, and wound into a cylindrical package.
A loom is a machine for effecting the interlacing of two series of yarns crossing one another at right angles. The warp yarns are wound on a warp beam and pass through heddles and reed. The filling is shot across in a shuttle and settled in place by reed and lay, and the fabric is wound on a cloth beam.
A starch mangle is a mangle that is used specifically for starching cotton goods. It commonly consists of two large rolls and a shallow open vat with several immersion rolls. The vat contains the starch solution.
A water mangle is a calender having two or more rolls used for squeezing water from fabrics before drying. Water mangles also may be used in other ways during the finishing of various fabrics.
A mule is a type of spinning frame having a head stock and a carriage as its two main sections. The head stock is stationary. The carriage is movable and it carries the spindles which draft and spin the roving into the yarn. The carriage extends over the whole width of the machine and moves slowly toward and away from the head stock during the spinning operation.
Nip shall mean the point of contact between two in-running rolls.
Openers and pickers means a general classification which includes breaker pickers, intermediate pickers, finisher pickers, single process pickers, multiple process pickers, willow machines, card and picker waste cleaners, thread extractors, shredding machines, roving waste openers, shoddy pickers, bale breakers, feeders, vertical openers, lattice cleaners, horizontal cleaners, and any similar machinery equipped with either cylinders, screen section, calender section, rolls, or beaters used for the preparation of stock for further processing.
A paddler consists of a trough for a solution and two or more squeeze rolls between which cloth passes after being passed through a mordant or dye bath.
Point of operation shall mean that part of the machine where the work of cutting, shearing, squeezing, drawing, or manipulating the stock in any other way is done.
A roller printing machine is a machine consisting of a large central cylinder, or pressure bowl, around the lower part of the perimeter of which is placed a series of engraved color rollers (each having a color trough), a furnisher roller, doctor blades, etc. The machine is used for printing fabrics.
Continuous bleaching ranges are of several types and may be made for cloth in rope or open-width form. The goods, after wetting out, pass through a squeeze roll into a saturator containing a solution of caustic soda and then to an enclosed J-box. A V-shaped arrangement is attached to the front part of the J-box for uniform and rapid saturation of the cloth with steam before it is packed down in the J-box. The cloth, in a single strand rope form, passes over a guide roll down the first arm of the “V” and up the second. Steam is injected into the “V” at the upper end of the second arm so that the cloth is rapidly saturated with steam at this point. The J-box capacity is such that cloth will remain hot for a sufficient time to complete the scouring action. It then passes a series of washers with a squeeze roll in between. The cloth then passes through a second set of saturator, J-box, and washer, where it is treated with the peroxide solution. By slight modification of the form of the unit, the same process can be applied to open-width cloth.
A mercerizing range consists generally of a 3-bowl mangle, a tenter frame, and a number of boxes for washing and scouring. The whole setup is in a straight line and all parts operate continuously. The combination is used to saturate the cloth with sodium hydroxide, stretch it while saturated, and washing out most of the caustic before releasing tension.
A sanforizing machine is a machine consisting of a large steam-heated cylinder, an endless, thick, woolen felt blanket which is in close contact with the cylinder for most of its perimeter, and an electrically heated shoe which presses the cloth against the blanket while the latter is in a stretched condition as it curves around feed-in roll.
A shearing machine is a machine used in shearing cloth. Cutting action is provided by a number of steel blades spirally mounted on a roller. The roller rotates in close contact with a fixed ledger blade. There may be from one to six such rollers on a machine.
A singeing machine is a machine used particularly with cotton; it comprises of a heated roller, plate, or an open gas flame. The material is rapidly passed over the roller or the plate or through the open gas flame to remove, fuzz or hairiness on yarn or cloth by burning.
A slasher is a machine used for applying a size mixture to warp yarns. Essentially, it consists of a stand for holding section beams, a size box, one or more cylindrical dryers or an enclosed hot air dryer, and a beaming end for finding the yarn on the loom beams.
Industrial organic solvent means any organic volatile liquid or compound, or any combination of these substances which are used to dissolve or suspend a nonvolatile or slightly volatile substance for industrial utilization. It shall also apply to such substances when used as detergents or cleansing agents. It shall not apply to petroleum products when such products are used as fuel.
A tenter frame is a machine for drying cloth under tension. It essentially consists of a pair of endless traveling chains fitted with clips of fine pins and carried on tracks. The cloth is firmly held at the selvages by the two chains which diverge as they move forward so that the cloth is brought to the desired width.
A warper is any machine for preparing and arranging the yarns intended for the warp of a fabric, specifically, a beam warper.
Stopping and starting handles shall be designed to the proper length to prevent the worker's hand or fingers from striking against any revolving part, gear guard, or any other part of the machine.
All guards and other safety devices, including starting and stopping devices, shall be properly maintained.
Lighting shall conform to American National Standard A11.1—1965, which is incorporated by reference as specified in § 1910.6.
Identification of piping systems shall conform to American National Standard A13.1—1956, which is incorporated by reference as specified in § 1910.6.
Identification of physical hazards shall be in accordance with the requirements of § 1910.144.
All pipes carrying steam or hot water for process or servicing machinery, when exposed to contact and located within seven feet of the floor or working platform shall be covered with a heat-insulating material, or otherwise properly guarded.
When any opening or picker machinery is equipped with a beater, such beater shall be provided with metal covers which will prevent contact with the beater. Such covers shall be provided with an interlock which will prevent the cover from being raised while the machine is in motion and prevent the operation of the machine while the cover is open.
Cleanout holes within reaching distance of the fan or picker beater shall have their covers securely fastened and they shall not be opened while the machine is in motion.
The feed rolls on all opening and picking machinery shall be covered with a guard designed to prevent the operator from reaching the nip while the machinery is in operation.
All textile opener lines shall be equipped with magnetic separators, tramp iron separators, or other means for the removal of foreign ferrous material.
Cylinder and lickerins shall be completely protected and the doffers should be enclosed.
The enclosures or covers shall be kept in place while the machine is in operation, except when stripping or grinding.
On operations calling for flat strippings which are allowed to fall on the doffer cover, where such strippings are removed by hand, the doffer cover shall be kept closed and securely fastened to prevent the opening of the cover while the machine is in operation. When it becomes necessary to clean the cards while they are in motion, a long-handled brush or dust mop shall be used.
Garnett lickerins shall be enclosed.
Garnett fancy rolls shall be enclosed by covers. These shall be installed in a way that keeps worker rolls reasonably accessible for removal or adjustment.
The underside of the garnett shall be guarded by a screen mesh or other form of enclosure to prevent access.
Vacuum relief valves shall conform to the ASME Code for Pressure Vessels, Section VIII, Unfired Pressure Vessels, 1968.
When slashers are operated by control levers, these levers shall be connected to a horizontal bar or treadle located not more than 69 inches above the floor to control the operation from any point.
Slashers operated by pushbutton control shall have stop and start buttons located at each end of the machine, and additional buttons located on both sides of the machine, at the size box and the delivery end. If calender rolls are used, additional buttons shall be provided at both sides of the machine at points near the nips, except when slashers are equipped with an enclosed dryer.
All nip guards shall comply with the requirements of paragraph (h)(2)(iv) of this section.
When enclosures or hoods are used over cylinder drying rolls, such enclosures or hoods shall be provided with an exhaust system which will effectively prevent wet air and steam from escaping into the workroom.
Slasher kettles and cookers shall be provided with expansion chambers in the covers, or drains, to prevent surging over. Steam-control valves shall be so located that they can be operated without exposing the worker to moving parts, hot surfaces, or steam.
When slashers are operated by control levers, these levers shall be connected to a horizontal bar or treadle located not more than 69 inches above the floor to control the operation from any point.
Slashers operated by push-button control shall have one start button at each end of the machine and stop buttons shall be located on both sides of the machines at intervals spaced not more than 6 feet on centers. Inching buttons should be installed.
The dryer enclosure shall be provided with an exhaust system which will effectively prevent wet air and steam from escaping into the workroom.
All nip guards shall comply with Table R-1.
| Distance of opening from nip point | Maximum width of opening |
|---|---|
| 0 to 1 1 ⁄ 2 | 1 ⁄ 4 |
| 1 1 ⁄ 2 to 2 1 ⁄ 2 | 3 ⁄ 8 |
| 2 1 ⁄ 2 to 3 1 ⁄ 2 | 1 ⁄ 2 |
| 3 1 ⁄ 2 to 5 1 ⁄ 2 | 5 ⁄ 8 |
| 5 1 ⁄ 2 to 6 1 ⁄ 2 | 3 ⁄ 4 |
| 6 1 ⁄ 2 to 7 1 ⁄ 2 | 7 ⁄ 8 |
| 7 1 ⁄ 2 to 8 1 ⁄ 2 | 1 1 ⁄ 4 |
| The measurements in Table R-1 are all in inches. |
Slasher kettles and cookers shall be provided with expansion chambers in the covers, or drains, to prevent surging over. Steam control valves shall be so located that they can be operated without exposing the worker to moving parts, hot surfaces, or steam.
Swiveled double-bar gates shall be installed on all warpers operating in excess of 450 yards per minute. These gates shall be so interlocked that the machine cannot be operated until the gate is in the “closed position,” except for the purpose of inching or jogging.
Closed position shall mean that the top bar of the gate shall be at least 42 inches from the floor or working platform; and the lower bar shall be at least 21 inches from the floor or working platform; and the gate shall be located 15 inches from the vertical tangent to the beam head.
A guard shall be placed ahead of the feed end and shall be so designed that it will prevent the worker's fingers from being caught in the pins of the intersecting fallers.
All nip guards shall comply with the requirements of paragraph (h)(2)(iv) of this section.
Covers for band pulleys shall be closed when the machine is in motion.
Branches or working platforms approximately 10 inches in height and 8 inches in width should be installed along the entire running length of the machine for the worker to stand on while creeling the machine. Such benches or platforms shall be covered with an abrasive or nonslip material.
Cover guard. An interlocking cover guard shall be installed over the large calender drums and the lap spool, designed to prevent the operator from coming in contact with the nip.
Each loom shall be equipped with a guard designed to minimize the danger of the shuttle flying out of the shed.
Provisions shall be made so that every loom fixer can prevent the loom from being started while he is at work on the loom. This may be accomplished by means of a lock, the key to which is retained in the possession of the loom fixer, or by some other effective means to prevent starting the loom.
All revolving blades on shearing machines shall be guarded so that the opening between the cloth surface and the bottom of the guard will not exceed three-eighths inch.
Each valve controlling the flow of steam, injurious gases, or liquids into a J-box shall be equipped with a chain, lock, and key, so that any worker who enters the J-box can lock the valve and retain the key in his possession. Any other method which will prevent steam, injurious gases, or liquids from entering the J-box while the worker is in it will be acceptable.
The nip of all in-running rolls on open-width bleaching machine rolls shall be protected with a guard to prevent the worker from being caught at the nip. The guard shall extend across the entire length of the nip.
Each valve controlling the flow of steam, injurious gases, or liquids into a kier shall be equipped with a chain, lock, and key, so that any worker who enters the kier can lock the valve and retain the key in his possession. Any other method which will prevent steam, injurious gases, or liquids from entering the kier while the worker is in it will be acceptable.
On new installations guardrails that comply with subpart D of this part shall be provided where workers are required to plait by hand from the top of the bin so as to protect the worker from falling to a lower level.
A stopping device shall be provided at each end of the machine.
A guard shall be installed at each end of the frame between the in-running chain and the clip opener, to prevent the worker's fingers from being caught.
The nip at the in-running rolls shall conform to § 1910.264.
A stopping device shall be provided at each end of the machine.
A guard shall be installed at each end of the frame at the in-running chain and clip opener.
Oil cups shall be safely located to permit easy access.
Each dye jig shall be equipped with individual mechanical or electrical means for stopping the machine.
Roll arms on jigs shall be built to allow for extra large batches, and to prevent the center bar from being forced off, causing the batch to fall.
Nip guards. All nip guards shall comply with the requirements of paragraph (h)(2)(iv) of this section.
Pressure reducing valves and pressure gages shall conform to the ASME Code for Pressure Vessels, Section VIII, 1968, Unfired Pressure Vessels.
If cans are not designed to prevent vacuum collapse, each can shall be equipped with one or more vacuum relief valves with openings of sufficient size to prevent the collapse of the can if vacuum occurs.
The feed rolls shall be guarded to conform to § 1910.264.
Pressure rolls shall be covered or guarded to conform to § 1910.264.
Each extractor shall be equipped with a metal cover.
Each extractor shall be equipped with an interlocking device that will prevent the cover from being opened while the basket is in motion, and also prevent the power operation of the basket while the cover is open.
Each extractor shall be equipped with a mechanically or electrically operated brake to quickly stop the basket when the power driving the basket is shut off.
Each centrifugal extractor shall be effectively secured in position on the floor or foundation so as to eliminate unnecessary vibration, and should not be operated at a speed greater than the manufacturer's rating, which shall be stamped where easily visible in letters not less than one-quarter inch in height. The maximum allowable speed shall be given in revolutions per minute (rpm).
Over-speed governor. Each engine individually driving an extractor shall be provided with an approved engine stop and speed limit governor.
Nip guards. All nip guards shall comply with the requirements of paragraph (h)(2)(iv) of this section.
All nip guards for water mangle, starch mangle, back-washer (worsted yarn) crabbing machines, decating machines, shall comply with the requirements of paragraph (h)(2)(iv).
A safety trip rod, cable, or wire center cord shall be provided across the front and back of all palmer cylinders extending the length of the face of the cylinder. It shall operate readily whether pushed or pulled. This safety trip shall be not more than 72 inches above the level on which the operator stands and shall be readily accessible.
Splash guards shall be installed on all rope washers unless the machine is so designed as to prevent the water or liquid from splashing the operator, the floor, or working surface.
A safety trip rod, cable or wire center cord shall be provided across the front and back of all rope washers extending the length of the face of the washer. It shall operate readily whether pushed or pulled. This safety trip shall be not more than 72 inches above the level on which the operator stands and shall be readily accessible.
Each drying tumbler, each double cylinder shaker or clothes tumbler, and each washing machine shall be equipped with an interlock device which will prevent the power operation of the inside cylinder when the outer door on the case or shell is open, and which will also prevent the outer door on the case or shell from being opened without shutting off the power.
All nip guards shall comply with the requirements of paragraph (h)(2)(iv) of this section.
The engraved roller gears and the large crown wheel shall be provided with a protective disc which will enclose the nips of the in-running gears. Individual discs for each nip will be acceptable.
The nip at the in-running side of the rolls shall be provided with a guard extending across the entire length of the nip and arranged to prevent the fingers of the workers from being pulled in between the rolls or between the guard and the rolls, and constructed so that the cloth can be fed into the rolls safely.
A guard shall be installed completely enclosing the cutters to prevent the hands of the operator from reaching the cutting zone.
An angle-iron-handle stop guard shall be installed at the right angle to the frame of the machine. The stop guard shall be so designed and so located that it will prevent the handle from traveling beyond the vertical position should the handle slip from the operator's hand when the pawl has been released from the teeth of the takeup gear.
Cleats shall be installed on the ends of roll benches.
The bottom of the overhead folders shall be located not less than 7 feet from the floor or working surface.
Floors in color-mixing rooms shall be constructed to drain easily.
Carboys shall be provided with inclinators, or the acid shall be withdrawn from the carboys by means of pumping without pressure in the carboy, or by means of hand operated siphons.
Means shall be provided for handling and emptying caustic soda and caustic potash containers to prevent workers from coming in contact with the caustic (see paragraph (qq) of this section).
Wherever acids or caustics are used, provision shall be made for a copious and flowing supply of fresh, clean water.
[39 FR 23502, June 27, 1974, as amended at 40 FR 23073, May 28, 1975; 49 FR 5324, Feb. 10, 1984; 61 FR 9241, Mar. 7, 1996; 63 FR 33467, June 18, 1998; 81 FR 83006, Nov. 18, 2016]
The requirements of this section shall apply to the design, installation, operation and maintenance of machinery and equipment used within a bakery.
All gears shall be completely enclosed regardless of location.
Sprockets and V-belt drives located within reach from platforms or pasageways or located within 8 feet 6 inches from the floor shall be completely enclosed.
Where machinery must be lubricated while in motion, stationary lubrication fittings inside a machine shall be provided with extension piping to a point of safety so that the employee will not have to reach into any dangerous part of the machine when lubricating.
Exposed hot water and steam pipes shall be covered with insulating material wherever necessary to protect employee from contact.
The back of the divider shall have a complete cover to enclose all of the moving parts, or each individual part shall be enclosed or guarded to remove the separate hazards. The rear cover shall be provided with a limit switch in order that the machine cannot operate when this cover is open. The guard on the back shall be hinged so that it cannot be completely removed and if a catch or brace is provided for holding the cover open, it shall be designed so that it will not release due to vibrations or minor bumping whereby the cover may drop on an employee.
Mechanical feed moulders shall be provided with hoppers so designed and connected to the proofer that an employee's hands cannot get into the hopper where they will come in contact with the in-running rolls.
Hand-fed moulders shall be provided with a belt-feed device or the hopper shall be extended high enough so that the hands of the operator cannot get into the feed rolls. The top edge of such a hopper shall be well rounded to prevent injury when it is struck or bumped by the employee's hand.
There shall be a stopping device within easy reach of the operator who feeds the moulder and another stopping device within the reach of the employee taking the dough away from the moulder.
The top roll shall be protected by a heavy gage metal shield extending over the roll to go within 6 inches of the hopper bottom board. The shield may be perforated to permit observation of the dough entering the rolls.
All door locks shall be operable both from within and outside the box. Guide rails shall be installed to center the rack as it enters, passes through, and leaves the proof box.
Fermentation room doors shall have nonshatterable wire glass or plastic panels for vision through doors.
Troughs shall be mounted on antifriction bearing casters thus making it possible for the operator to move and direct the motion of the trough with a minimum of effort.
A lock or other device shall be provided to hold the handle in vertical position when the truck is not in use.
Separate flues shall be provided, (i) for venting vapors from the frying section, and (ii) for venting products of combustion from the combustion chamber used to heat the fat.
Reversible brakes shall be provided with a guard or tripping mechanism on each side of the rolls. These guards shall be so arranged as to stop the machine or reverse the direction of the rolls so that they are outrunning if the guard is moved by contact of the operator.
Cross-roll brakes shall be provided with guards that are similar in number and equal in effectiveness to guards on hand-fed brakes.
Mechanically operated peanut cooling trucks shall have a grid-type cover over the entire top.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49765, Oct. 24, 1978; 43 FR 51760, Nov. 7, 1978; 61 FR 9241, Mar. 7, 1996]
This section applies to moving parts of equipment used in laundries and to conditions peculiar to this industry, with special reference to the point of operation of laundry machines. This section does not apply to dry-cleaning operations.
Provisions of paragraph (c)(2) (iii), (iv)( a )( 1 ), and (iv)( b ) of this section shall not apply to shakeout or conditioning tumblers where the clothes are loaded into the open end of the revolving cylinder and are automatically discharged out of the opposite end.
Markers and others handling soiled clothes shall be warned against touching the eyes, mouth, or any part of the body on which the skin has been broken by a scratch or abrasion; and they shall be cautioned not to touch or eat food until their hands have been thoroughly washed.
Employees shall be properly instructed as to the hazards of their work and be instructed in safe practices, by bulletins, printed rules, and verbal instructions.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49767, Oct. 24, 1978; 43 FR 51760, Nov. 7, 1978]
This section includes safety requirements for sawmill operations including, but not limited to, log and lumber handling, sawing, trimming, and planing; waste disposal; operation of dry kilns; finishing; shipping; storage; yard and yard equipment; and for power tools and affiliated equipment used in connection with such operations, but excluding the manufacture of plywood, cooperage, and veneer.
The term A-frame means a structure made of two independent columns fastened together at the top and separated at the bottom for stability.
The term annealing means heating then cooling to soften and render less brittle.
The term binder means a chain, cable, rope, or other approved material used for binding loads.
The term boom means logs or timbers fastened together end to end and used to contain floating logs. The term includes enclosed logs.
The term brow log means a log placed parallel to a roadway at a landing or dump to protect vehicles while loading or unloading.
The term bunk means a cross support for a load.
The term cant means a log slabbed on one or more sides.
The term carriage means a framework mounted on wheels which runs on tracks or in grooves in a direction parallel to the face of the saw, and which contains apparatus to hold a log securely and advance it towards the saw.
The term carrier means an industrial truck so designed and constructed that it straddles the load to be transported with mechanisms to pick up the load and support it during transportation.
The term chipper means a machine which cuts material into chips.
The terms chock, bunk block, and cheese block mean a wedge that prevents logs or loads from moving.
The term cold deck means a pile of logs stored for future removal.
The term crotch lines means two short lines attached to a hoisting line by a ring or shackle, the lower ends being attached to loading hooks.
The term dog means a steel tooth, one or more of which are attached to each carriage knee to hold log firmly in place on carriage.
The term drag saw means a power-driven, reciprocating crosscut saw mounted on suitable frame and used for bucking logs.
The term head block means that part of a carriage which holds the log and upon which it rests. It generally consists of base, knee, taper set, and mechanism.
The term head rig means a combination of head saw and log carriage used for the initial breakdown of logs into timbers, cants, and boards.
The term hog means a machine for cutting or grinding slabs and other coarse residue from the mill.
The term husk means a head saw framework on a circular mill.
The term industrial truck means a mobile powerdriven truck or tractor.
The term kiln tender means the operator of a kiln.
The term lift truck means an industrial truck used for lateral transportation and equipped with a power-operated lifting device, usually in the form of forks, for piling or unpiling lumber units or packages.
The term live rolls means cylinders of wood or metal mounted on horizontal axes and rotated by power, which are used to convey slabs, lumber, and other wood products.
The term loading boom means any structure projecting from a pivot point to guide a log when lifted.
The term Log deck means a platform in the sawmill on which the logs remain until needed for sawing.
The term lumber hauling truck means an industrial truck, other than a lift truck or a carrier, used for the transport of lumber.
The term log haul means a conveyor for transferring logs to mill.
The term package means a unit of lumber.
The term peavy means a stout wooden handle fitted with a spike and hook and used for rolling logs.
The term pike pole means a long pole whose end is shod with a sharp pointed spike.
The term pitman rod means connecting rod.
The term resaw means band, circular, or sash gang saws used to break down slabs, cants, or flitches into lumber.
The term running line means any moving rope as distinguished from a stationary rope such as a guyline.
The term safety factor means a calculated reduction factor which may be applied to laboratory test values to obtain safe working stresses for wooden beams and other mechanical members; ratio of breaking load to safe load.
The term saw guide means a device for steadying a circular or bandsaw.
The term setwork means a mechanism on a sawmill carriage which enables an operator to move the log into position for another cut.
The term sorting gaps means the areas on a log pond enclosed by boom sticks into which logs are sorted.
The term spreader wheel means a metal wheel that separates the board from the log in back of circular saws to prevent binding.
The term splitter means a knife-type, nonrotating spreader.
The term sticker means a strip of wood or other material used to separate layers of lumber.
The term stiff boom means the anchored, stationary boom sticks which are tied together and on which boom men work.
The term swifter is a means of tying boom sticks together to prevent them from spreading while being towed.
The term telltale means a device used to serve as a warning for overhead objects.
The term top saw means the upper of two circular saws on a head rig, both being on the same husk.
The term tramway means a way for trams, usually consisting of parallel tracks laid on wooden beams.
The term trestle means a braced framework of timbers, piles or steelwork for carrying a road or railroad over a depression.
All buildings, docks, tramways, walkways, log dumps, and other structures shall be designed, constructed and maintained so as to support the imposed load in accordance with a safety factor.
Work areas under mills shall be as evenly surfaced as local conditions permit. They shall be free from unnecessary obstructions and provided with lighting facilities in accordance with American National Standard for Industrial Lighting A11.1—1965, which is incorporated by reference as specified in § 1910.6.
Flooring in buildings and on ramps and walkways shall be constructed and installed in accordance with established principles of mechanics and sound engineering practices. They shall be of adequate strength to support the estimated or actual dead and live loads acting on them with the resultant stress not exceeding the allowable stress for the material being used.
Areas under floor openings shall, where practical, be fenced off. When this is not practical, they shall be plainly marked and telltales shall be installed to hang over these areas.
The flooring of buildings, docks, and passageways shall be kept in good repair. When a hazardous condition develops that cannot be immediately repaired, the area shall be guarded until adequate repairs are made.
Floors, footwalks, and passageways in the work area around machines or other places where a person is required to stand or walk shall be provided with effective means to minimize slipping.
Walkways, docks, and platforms shall be of sufficient width to provide adequate passage and working areas.
Walkways shall be evenly floored and kept in good repair.
Docks and runways used for the operation of lift trucks and other vehicles shall have a substantial guard or shear timber except where loading and unloading are being performed.
All elevated walks, runways, or platforms, if 4 feet or more from the floor level, shall be provided with a standard railing except on loading or unloading sides of platforms. If height exceeds 6 feet, a standard toe board also shall be provided to prevent material from rolling or falling off.
Where elevated platforms are used routinely on a daily basis, they shall be equipped with stairways or fixed ladders that comply with subpart D of this part.
Where required, walkways and stairways with standard handrails shall be provided in elevated and hazardous locations. Where such passageways are over walkways or work areas, standard toe boards shall be provided.
Stairways shall be constructed in accordance with subpart D of this part.
Stairways shall be provided with a standard handrail on at least one side or on any open side. Where stairs are more than four feet wide there shall be a standard handrail at each side, and where more than eight feet wide, a third standard handrail shall be erected in the center of the stairway.
All stairways shall be adequately lighted as prescribed in paragraph (c)(9) of this section.
Doors shall not open directly on or block a flight of stairs, and shall swing in the direction of exit travel.
Exits shall be located and identified in a manner that affords ready exit from all work areas.
All swinging doors shall be provided with windows; with one window for each section of double swinging doors. Such windows shall be of shatterproof or safety glass unless otherwise protected against breakage.
Where sliding doors are used as exits, an inner door shall be cut inside each of the main doors and arranged to open outward.
Where a doorway opens upon a railroad track or upon a tramway or dock over which vehicles travel, a barrier or other warning device shall be placed to prevent workmen from stepping into moving traffic.
Ventilation shall be provided to supply adequate fresh healthful air to rooms, buildings, and work areas.
All open vats and tanks into which workmen could fall shall be guarded.
Illumination shall be provided and designed to supply adequate general and local lighting to rooms, buildings, and work areas during the time of use.
Factors upon which the adequacy and effectiveness of illumination will be judged, include the following:
Physical hazard marking shall be as specified in § 1910.144 of this part.
Means shall be provided to block, chain, or otherwise secure equipment normally supported by hydraulic pressure so as to provide for safe maintenance.
All gas piping and appliances shall be installed in accordance with the American National Standard Requirements for the Installation of Gas Appliances and Gas Piping Z21.30—1964, which is incorporated by reference as specified in § 1910.6.
Construction, operation, and maintenance of conveyors shall be in accordance with American National Standard B20.1—1957, which is incorporated by reference as specified in § 1910.6.
Spiked live rolls shall be guarded.
Tramways and trestles shall have substantial mud sills or foundations which shall be frequently inspected and kept in repair. When vehicles are operated on tramways and trestles which are used for foot passage, traffic shall be controlled or a walkway with standard handrails at the outer edge and shear timber on the inner edge shall be provided. This walkway shall be wide enough to allow adequate clearance to vehicles. When walkways cross over other thoroughfares, they shall be solidly fenced at the outer edge to a height of 42 inches over such thoroughfares.
Stationary tramways and trestles shall have a vertical clearance of 22 feet over railroad rails. When constructed over carrier docks or roads, they shall have a clearance of 6 feet above the driver's foot rest on the carrier, and in no event shall this clearance be less than 12 feet from the roadway. In existing operations where it is impractical to obtain such clearance, telltales, electric signals, signs or other precautionary measures shall be installed.
All mills containing one or more machines that create dust, shavings, chips, or slivers during a period of time equal to or greater than one-fourth of the working day, shall be equipped with a collecting system. It may be either continuous or automatic, and shall be of sufficient strength and capacity to enable it to remove such refuse from points of operation and immediate vicinities of machines and work areas.
Each woodworking machine that creates dust, shavings, chips, or slivers shall be equipped with an exhaust or conveyor system located and adjusted to remove the maximum amount of refuse from the point of operation and immediate vicinity.
Exhaust pipes shall not discharge into an unconfined outside pile if uncontrolled fire or explosion hazards are created. They may empty into settling or dust chambers, designed to prevent the dust or refuse from entering any work area. Such chambers shall be constructed and operated to minimize the danger of fire or dust explosion.
Provision for the daily removal of refuse shall be made in all operations not required to have an exhaust system or having refuse too heavy, bulky, or otherwise unsuitable to be handled by the exhaust system.
The feed system to the chipper shall be arranged so the operator does not stand in direct line with the chipper spout (hopper). The chipper spout shall be enclosed to a height of not less than 36 inches from the floor or the operator's platform. A safety belt and lifeline shall be worn by workmen when working at or near the spout unless the spout is guarded. The lifeline shall be short enough to prevent workers from falling into the chipper.
Open bins, bunkers, and hoppers whose upper edges extend less than 3 feet above working level shall be equipped with standard handrails and toe boards, or have their tops covered by a substantial grill or grating with openings small enough to prevent a man from falling through.
Where automotive or other wheeled equipment is used to move materials into bins, bunkers, and hoppers, adequate guard rails shall be installed along each side of the runway, and a substantial bumper stop provided when necessary.
Where needed, fuel houses and bins shall have a standard railed platform or walkway near the top.
Ropes, cables, slings, and chains shall be used in accordance with safe use practices recommended by the manufacturer or within safe limits recommended by the equipment manufacturer when used in conjunction with it.
No open hook shall be used in rigging to lift any load where there is hazard from relieving the tension on the hook from the load or hook catching or fouling.
Installation, inspection, maintenance, repair, and testing of ropes, cables, slings, and chains shall be done only by persons qualified to do such work.
Proper storage shall be provided for slings while not in use.
Connections, fittings, fastenings, and other parts used in connection with ropes and cables shall be of good quality and of proper size and strength, and shall be installed in accordance with the manufacturer's recommendations.
Hooks, shackles, rings, pad eyes, and other fittings that show excessive wear or that have been bent, twisted, or otherwise damaged shall be removed from service.
Running lines of hoisting equipment located within 6 feet 6 inches of the ground or working level shall be boxed off or otherwise guarded, or the operating area shall be restricted.
There shall be not less than two full wraps of hoisting cable on the drum of cranes and hoists at all times of operation.
Drums shall have a flange at each end to prevent the cable from slipping off.
Bottom sheaves shall be protected by close fitting guards to prevent cable from jumping the sheave.
The reeving of a rope shall be so arranged as to minimize chafing or abrading while in use.
Lumber lifting devices on all stackers shall be designed and arranged so as to minimize the possibility of lumber falling from such devices.
Means shall be provided to positively block the hoisting platform when employees must go beneath the stacker or unstacker hoist.
Every manually operated control switch shall be properly identified and so located as to be readily accessible to the operator.
Main control switches shall be so designed that they can be locked in the open position.
The hoistway side openings at the top level of the stacker and unstacker shall be protected by enclosures of standard railings.
When the hoist platform or top of the load is below the working platform, the hoistway openings shall be guarded.
The lower landing area of stackers and unstackers shall be guarded by enclosures that prevent entrance to the area or pit below the hoist platform. Entrances should be protected by electrically interlocked gates which, when open, will disconnect the power and set the hoist brakes. When the interlock is not installed, other positive means of protecting the entrance shall be provided.
Every stacker and unstacker shall be inspected at frequent intervals and all defective parts shall be immediately repaired or replaced.
Safe means of entrance and exit shall be provided to permit cleaning of pits.
Where the return of trucks from unstacker to stacker is by mechanical power or gravity, adequate signs, warning devices, or barriers shall be erected to prevent entry into the hazardous area.
In stacking units of lumber, pile foundations shall be designed and arranged to support maximum loads without sinking, sagging, or permitting the piles to topple. In unit package piles, substantial bolsters or unit separators shall be placed between each package directly over the stickers.
Long units of lumber shall not be stacked upon shorter packages except where a stable pile can be made with the use of package separators.
Piles of lumber which have become unstable shall be immediately made safe, or the area into which they might fall shall be fenced or barricaded and employees prohibited from entering it.
Unit packages of lumber shall be provided with stickers as necessary to insure stability under ordinary operating conditions.
Stickers shall extend the full width of the package, shall be uniformly spaced, and shall be aligned one above the other. Stickers may be lapped with a minimum overlapping of 12 inches. Stickers shall not protrude more than 2 inches beyond the sides of the package.
The height of unit package piles shall be dependent on the dimensions of the packages and shall be such as to provide stability under normal operating conditions. Adjacent lumber piles may be tied together with separators to increase stability.
Loads shall be built and secured to insure stability in transit.
If the burner stack is not self-supporting, it shall be guyed or otherwise supported.
The conveyor runway to the burner shall be equipped with a standard handrail. If the runway crosses a roadway or thoroughfare, standard toe boards shall be provided in addition.
Vehicles shall include all mobile equipment normally used in sawmill, planing mill, storage, shipping, and yard operations.
All vehicles shall be equipped with audible warning signals and where practicable shall have spark arrestors.
All vehicles operated in the dark or in poorly lighted areas shall be equipped with head and tail lights.
All vehicles operated in areas where overhead hazards exist shall be equipped with an approved overhead guard. See American National Standard Safety Code for Powered Industrial Trucks, B56.1—1969, which is incorporated by reference as specified in § 1910.6.
Where the operator is exposed to hazard from backing the vehicle into objects, an approved platform guard shall be provided and so arranged as to not impede exit of driver from vehicle.
Vehicles powered by internal combustion engines shall not operate in buildings unless the buildings are adequately ventilated.
No vehicle shall be operated with loads exceeding its safe load capacity.
All vehicles shall be equipped with brakes capable of holding and controlling the vehicle and capacity load upon any incline or grade over which they may be operated.
Railroad tracks and other hazardous crossings shall be plainly posted.
All areas of restricted side or overhead clearance shall be plainly marked.
Pickup and unloading points and paths for lumber packages on conveyors and transfers and other areas where accurate spotting is required, shall be plainly marked and wheel stops provided where necessary.
46 CFR 160.099 and 46 CFR 160.050) with line attached and maintained to retain buoyancy shall be provided.
The applicable provisions of the Standard for Fire Protection for Motorcraft, NFPA No. 302—1968, which is incorporated by reference as specified in § 1910.6, shall be complied with.
Safe access to the head rig shall be provided.
Log decks shall be provided with adequate stops, chains, or other safeguards to prevent logs from rolling down the deck onto the carriage or its runway.
A barricade or other positive stop of sufficient strength to stop any log shall be erected between the sawyer's stand and the log deck.
Loose chains from overhead canting devices or other equipment shall not be allowed to hang over the log deck in such manner as to strike employees.
Swing saws on log decks shall be equipped with a barricade and stops for protection of employees who may be on the opposite side of the log haul chute.
Where reciprocating log cutoff saws (drag saws) are provided, they shall not project into walkway or aisle.
Circular log bucking or cutoff saws shall be so located and guarded as to allow safe entrance to and exit from the building.
Where the cutoff saw partially blocks the entrance from the log haul runway, the entrance shall be guarded.
Rotary barking devices shall be so guarded as to protect employees from flying chips, bark, or other extraneous material.
If an elevating ramp or gate is used, it shall be provided with a safety chain, hook, or other means of suspension while employees are underneath.
The hazardous area around ring barkers and their conveyors shall be fenced off or posted as a prohibited area for unauthorized persons.
Hydraulic barkers shall be enclosed with strong baffles at the inlet and outlet. The operator shall be protected by adequate safety glass or equivalent.
Holddown rolls shall be installed at the infeed and outfeed sections of mechanical ring barkers to control the movement of logs.
A substantial stop or bumper with adequate shock-absorptive qualities shall be installed at each end of the carriage runway.
Rider-type carriages shall be floored to provide secure footing and a firm working platform for the block setter.
Sheaves on rope-driven carriages shall be guarded at floor line with substantial housings.
A positive means shall be provided to prevent unintended movement of the carriage. This may involve a control locking device, a carriage tie-down, or both.
A barrier shall be provided to prevent employees from entering the space necessary for travel of the carriage, with headblocks fully receded, for the full length and extreme ends of carriage runways. Warning signs shall be posted at possible entry points to this area.
For a rider-type carriage adequate overhead clear space above the carriage deck shall be provided for the full carriage runway length.
Carriage track sweeping devices shall be used to keep track rails clear of debris.
Dogging devices shall be adequate to secure logs, cants, or boards, during sawing operations.
Twin circular head saws rigs such as scrag saws shall meet the specifications for single circular head saws in paragraph (e)(2)(iii) of this section where applicable.
Band resaws shall meet the specifications for band head saws as required by paragraph (e)(2)(i) of this section.
Sash gang resaws shall meet the safety specifications of whole-log sash gang saws in accordance with the requirements of paragraph (e)(2)(v) of this section.
Trimmer saws shall not be run at peripheral speeds in excess of those recommended by the manufacturer.
Automatic trimmer saws shall be provided with safety stops or hangers to prevent saws from dropping on table.
Live rolls and tailing devices in back of edger shall operate at a speed not less than the speed of the edger feed rolls.
Dry kilns shall be constructed upon solid foundations to prevent tracks from sagging
A passageway shall be provided to give adequate clearance on at least one side or in the center of end-piled kilns and on two sides of cross-piled kilns.
Pits shall be well ventilated, drained, and lighted, and shall be large enough to safely accommodate the kiln operator together with operating devices such as valves, dampers, damper rods, and traps.
All high-pressure steam mains located in or adjacent to an operating pit shall be covered with heat-insulating material.
A fixed ladder complying with the requirements of subpart D of this part, or other adequate means, shall be provided to permit access to the roof. Where controls and machinery are mounted on the roof, a permanent stairway with standard handrail shall be installed in accordance with the requirements in subpart D.
A means shall be provided for chocking or blocking cars.
A warm room shall be provided for kiln employees to stay in during cold weather after leaving a hot kiln.
[39 FR 23502, June 27, 1974, as amended at 40 FR 23073, May 28, 1975; 43 FR 49751, Oct. 24, 1978; 43 FR 51760, Nov. 7, 1978; 53 FR 12123, Apr. 12, 1988; 55 FR 32015, Aug. 6, 1990; 61 FR 9241, Mar. 7, 1996; 63 FR 33467, June 18, 1998; 70 FR 53929, Sept. 13, 2005; 76 FR 80739, Dec. 27, 2011; 81 FR 83006, Nov. 18, 2016]
This paragraph contains the list of paragraphs and appendices contained in this section.
a. Table of contents
b. Scope and application
c. Definitions
d. General requirements
1. Personal protective equipment
2. First-aid kits
3. Seat belts
4. Fire extinguishers
5. Environmental conditions
6. Work areas
7. Signaling and signal equipment
8. Overhead electric lines
9. Flammable and combustible liquids
10. Explosives and blasting agents
e. Hand and portable powered tools
1. General requirements
2. Chain saws
f. Machines
1. General requirements
2. Machine operation
3. Protective structures
4. Overhead guards
5. Machine access
6. Exhaust systems
7. Brakes
8. Guarding
g. Vehicles
h. Tree harvesting
1. General requirements
2. Manual felling
3. Bucking and limbing
4. Chipping
5. Yarding
6. Loading and unloading
7. Transport
8. Storage
i. Training
j. Appendices
Appendix A—Minimum First-aid Supplies
Appendix B—Minimum First-aid Training
Appendix C—Corresponding ISO Agreements
Arch. An open-framed trailer or built-up framework used to suspend the leading ends of trees or logs when they are skidded.
Backcut (felling cut). The final cut in a felling operation.
Ballistic nylon. A nylon fabric of high tensile properties designed to provide protection from lacerations.
Buck. To cut a felled tree into logs.
Butt. The bottom of the felled part of a tree.
Cable yarding. The movement of felled trees or logs from the area where they are felled to the landing on a system composed of a cable suspended from spars and/or towers. The trees or logs may be either dragged across the ground on the cable or carried while suspended from the cable.
Chock. A block, often wedge shaped, which is used to prevent movement; e.g., a log from rolling, a wheel from turning.
Choker. A sling used to encircle the end of a log for yarding. One end is passed around the load, then through a loop eye, end fitting or other device at the other end of the sling. The end that passed through the end fitting or other device is then hooked to the lifting or pulling machine.
Danger tree. A standing tree that presents a hazard to employees due to conditions such as, but not limited to, deterioration or physical damage to the root system, trunk, stem or limbs, and the direction and lean of the tree.
Debark. To remove bark from trees or logs.
Deck. A stack of trees or logs.
Designated person. An employee who has the requisite knowledge, training and experience to perform specific duties.
Domino felling. The partial cutting of multiple trees which are left standing and then pushed over with a pusher tree.
Fell (fall). To cut down trees.
Feller (faller). An employee who fells trees.
Grounded. The placement of a component of a machine on the ground or on a device where it is firmly supported.
Guarded. Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable enclosures, covers, casings, shields, troughs, railings, screens, mats, or platforms, or by location, to prevent injury.
Health care provider. A health care practitioner operating with the scope of his/her license, certificate, registration or legally authorized practice.
Landing. Any place where logs are laid after being yarded, and before transport from the work site.
Limbing. To cut branches off felled trees.
Lodged tree (hung tree). A tree leaning against another tree or object which prevents it from falling to the ground.
Log. A segment sawed or split from a felled tree, such as, but not limited to, a section, bolt, or tree length.
Logging operations. Operations associated with felling and moving trees and logs from the stump to the point of delivery, such as, but not limited to, marking danger trees and trees/logs to be cut to length, felling, limbing, bucking, debarking, chipping, yarding, loading, unloading, storing, and transporting machines, equipment and personnel to, from and between logging sites.
Machine. A piece of stationary or mobile equipment having a self-contained powerplant, that is operated off-road and used for the movement of material. Machines include, but are not limited to, tractors, skidders, front-end loaders, scrapers, graders, bulldozers, swing yarders, log stackers, log loaders, and mechanical felling devices, such as tree shears and feller-bunchers. Machines do not include airplanes or aircraft (e.g., helicopters).
Rated capacity. The maximum load a system, vehicle, machine or piece of equipment was designed by the manufacturer to handle.
Root wad. The ball of a tree root and dirt that is pulled from the ground when a tree is uprooted.
Serviceable condition. A state or ability of a tool, machine, vehicle or other device to operate as it was intended by the manufacturer to operate.
Skidding. The yarding of trees or logs by pulling or towing them across the ground.
Slope (grade). The increase or decrease in altitude over a horizontal distance expressed as a percentage. For example, a change of altitude of 20 feet (6 m) over a horizontal distance of 100 feet (30 m) is expressed as a 20 percent slope.
Snag. Any standing dead tree or portion thereof.
Spring pole. A tree, segment of a tree, limb, or sapling which is under stress or tension due to the pressure or weight of another object.
Tie down. Chain, cable, steel strips or fiber webbing and binders attached to a truck, trailer or other conveyance as a means to secure loads and to prevent them from shifting or moving when they are being transported.
Undercut. A notch cut in a tree to guide the direction of the tree fall and to prevent splitting or kickback.
Vehicle. A car, bus, truck, trailer or semi-trailer owned, leased or rented by the employer that is used for transportation of employees or movement of material.
Winching. The winding of cable or rope onto a spool or drum.
Yarding. The movement of logs from the place they are felled to a landing.
For each vehicle or machine (equipped with ROPS/FOPS or overhead guards), including any vehicle or machine provided by an employee, the employer shall assure:
The employer shall provide and maintain portable fire extinguishers on each machine and vehicle in accordance with the requirements of subpart L of part 1910.
All work shall terminate and each employee shall move to a place of safety when environmental conditions, such as but not limited to, electrical storms, strong winds which may affect the fall of a tree, heavy rain or snow, extreme cold, dense fog, fires, mudslides, and darkness, create a hazard for the employee in the performance of the job.
shall be tested, installed, and maintained in serviceable condition.
shall be installed, tested and maintained in accordance with the Society of Automotive Engineers SAE J231, January 1981, “Minimum Performance Criteria for Falling Object Protective Structures (FOPS)”, which is incorporated by reference as specified in § 1910.6.
and FOPS shall meet the requirements of the Society of Automotive Engineers SAE J397, April 1988, “Deflection Limiting Volume-ROPS/FOPS Laboratory Evaluation”, which is incorporated by reference as specified in § 1910.6.
Each forklift shall be equipped with an overhead guard meeting the requirements of the American Society of Mechanical Engineers, ASME B56.6-1992 (with addenda), “Safety Standard for Rough Terrain Forklift Trucks”, which is incorporated by reference as specified in § 1910.6.
The transport vehicle operator shall assure that each tie down is tight before transporting the load. While enroute, the operator shall check and tighten the tie downs whenever there is reason to believe that the tie downs have loosened or the load has shifted.
Each deck shall be constructed and located so it is stable and provides each employee with enough room to safely move and work in the area.
Training shall be provided as follows:
At a minimum, training shall consist of the following elements:
The employer shall hold safety and health meetings as necessary and at least each month for each employee. Safety and health meetings may be conducted individually, in crew meetings, in larger groups, or as part of other staff meetings.
Appendices A and B of this section are mandatory. The information contained in appendix C of this section is informational and is not intended to create any additional obligations not otherwise imposed or to detract from existing regulations.
Appendix A to § 1910.266—First-Aid Kits (Mandatory)
The following list sets forth the minimally acceptable number and type of first-aid supplies for first-aid kits required under paragraph (d)(2) of the logging standard. The contents of the first-aid kit listed should be adequate for small work sites, consisting of approximately two to three employees. When larger operations or multiple operations are being conducted at the same location, additional first-aid kits should be provided at the work site or additional quantities of supplies should be included in the first-aid kits:
1. Gauze pads (at least 4 × 4 inches).
2. Two large gauze pads (at least 8 × 10 inches).
3. Box adhesive bandages (band-aids).
4. One package gauze roller bandage at least 2 inches wide.
5. Two triangular bandages.
6. Wound cleaning agent such as sealed moistened towelettes.
7. Scissors.
8. At least one blanket.
9. Tweezers.
10. Adhesive tape.
11. Latex gloves.
12. Resuscitation equipment such as resuscitation bag, airway, or pocket mask.
13. Two elastic wraps.
14. Splint.
15. Directions for requesting emergency assistance.
Appendix B to § 1910.266—First-aid and CPR Training (Mandatory)
The following is deemed to be the minimal acceptable first-aid and CPR training program for employees engaged in logging activities.
First-aid and CPR training shall be conducted using the conventional methods of training such as lecture, demonstration, practical exercise and examination (both written and practical). The length of training must be sufficient to assure that trainees understand the concepts of first aid and can demonstrate their ability to perform the various procedures contained in the outline below.
At a minimum, first-aid and CPR training shall consist of the following:
1. The definition of first aid.
2. Legal issues of applying first aid (Good Samaritan Laws).
3. Basic anatomy.
4. Patient assessment and first aid for the following:
a. Respiratory arrest.
b. Cardiac arrest.
c. Hemorrhage.
d. Lacerations/abrasions.
e. Amputations.
f. Musculoskeletal injuries.
g. Shock.
h. Eye injuries.
i. Burns.
j. Loss of consciousness.
k. Extreme temperature exposure (hypothermia/hyperthermia)
l. Paralysis
m. Poisoning.
n. Loss of mental functioning (psychosis/hallucinations, etc.). Artificial ventilation.
o. Drug overdose.
5. CPR.
6. Application of dressings and slings.
7. Treatment of strains, sprains, and fractures.
8. Immobilization of injured persons.
9. Handling and transporting injured persons.
10. Treatment of bites, stings, or contact with poisonous plants or animals.
Appendix C to § 1910.266—Comparable ISO Standards (Non-mandatory)
The following International Labor Organization (ISO) standards are comparable to the corresponding Society of Automotive Engineers (Standards that are referenced in this standard.)
Utilization of the ISO standards in lieu of the corresponding SAE standards should result in a machine that meets the OSHA standard.
| SAE standard | ISO standard | Subject |
|---|---|---|
| SAE J1040 | ISO 3471-1 | Performance Criteria for Rollover Protective Structures (ROPS) for Construction, Earthmoving, Forestry and Mining Machines. |
| SAE J397 | ISO 3164 | Deflection Limiting Volume—ROPS/FOPS Laboratory Evaluation. |
| SAE J231 | ISO 3449 | Minimum Performance Criteria for Falling Object Protective Structures (FOPS). |
| SAE J386 | ISO 6683 | Operator Restraint Systems for Off-Road Work Machines. |
| SAE J185 | ISO 2897 | Access Systems for Off-Road Machines. |
[59 FR 51741, Oct. 12, 1994, as amended at 60 FR 7449, Feb. 8, 1995; 60 FR 40458, Aug. 9, 1996; 60 FR 47035, Sept. 8, 1995; 61 FR 9241, 9242, Mar. 7, 1996; 69 FR 18803, Apr. 9, 2004; 71 FR 16673, Apr. 3, 2006; 79 FR 37190, July 1, 2014]
Lighting in telecommunication centers shall be provided in an adequate amount such that continuing work operations, routine observations, and the passage of employees can be carried out in a safe and healthful manner. Certain specific tasks in centers, such as splicing cable and the maintenance and repair of equipment frame lineups, may require a higher level of illumination. In such cases, the employer shall install permanent lighting or portable supplemental lighting to attain a higher level of illumination shall be provided as needed to permit safe performance of the required task.
Guard rails and toe boards may be omitted on distribution frame mezzanine platforms to permit access to equipment. This exemption applies only on the side or sides of the platform facing the frames and only on those portions of the platform adjacent to equipped frames.
Maintenance aisles, or wiring aisles, between equipment frame lineups are working spaces and are not an exit route for purposes of 29 CFR 1910.34.
When blastproof or power actuated doors are installed in specially designed hardsite security buildings and spaces, they shall be designed and installed so that they can be used as a means of egress in emergencies.
Highway mobile vehicles and trailers stored in garages in accordance with § 1910.110 may be equipped to carry more than one LP-gas container, but the total capacity of LP-gas containers per work vehicle stored in garages shall not exceed 100 pounds of LP-gas. All container valves shall be closed when not in use.
When using or transporting nitrogen cylinders in a horizontal position, special compartments, racks, or adequate blocking shall be provided to prevent cylinder movement. Regulators shall be removed or guarded before a cylinder is transported.
No employee, or any material or equipment, may be supported or permitted to be supported on any portion of a pole structure, platform, ladder, walkway or other elevated structure or aerial device unless the employer ensures that the support structure is first inspected by a competent person and it is determined to be adequately strong, in good working condition and properly secured in place.
| Voltage range (phase to phase, RMS) | Approach distance (inches) |
|---|---|
| 300 V and less | ( 1 ) |
| Over 300V, not over 750V | 12 |
| Over 750V not over 2 kV | 18 |
| Over 2 kV, not over 15 kV | 24 |
| Over 15 kV, not over 37 kV | 36 |
| Over 37 kV, not over 87.5 kV | 42 |
| Over 87.5 kV, not over 121 kV | 48 |
| Over 121 kV, not over 140 kV | 54 |
| 1 Avoid contact. |
Whenever natural light is insufficient to adequately illuminate the worksite, artificial illumination shall be provided to enable the employee to perform the work safely.
Employers shall provide training in the various precautions and safe practices described in this section and shall insure that employees do not engage in the activities to which this section applies until such employees have received proper training in the various precautions and safe practices required by this section. However, where the employer can demonstrate that an employee is already trained in the precautions and safe practices required by this section prior to his employment, training need not be provided to that employee in accordance with this section. Where training is required, it shall consist of on-the-job training or classroom-type training or a combination of both. The employer shall certify that employees have been trained by preparing a certification record which includes the identity of the person trained, the signature of the employer or the person who conducted the training, and the date the training was completed. The certification record shall be prepared at the completion of training and shall be maintained on file for the duration of the employee's employment. The certification record shall be made available upon request to the Assistant Secretary for Occupational Safety and Health. Such training shall, where appropriate, include the following subjects:
Personal protective equipment, protective devices and special tools needed for the work of employees shall be provided and the employer shall ensure that they are used by employees. Before each day's use the employer shall ensure that these personal protective devices, tools, and equipment are carefully inspected by a competent person to ascertain that they are in good condition.
| Gloves, blankets, and other insulating equipment | Natural rubber | Synthetic rubber |
|---|---|---|
| Months | ||
| New | 12 | 18 |
| Re-issued | 9 | 15 |
A positioning system or a personal fall arrest system shall be provided and the employer shall ensure their use when work is performed at positions more than 4 feet (1.2 m) above the ground, on poles, and on towers, except as provided in paragraphs (n)(7) and (8) of this section. These systems shall meet the applicable requirements in subpart I of this part. The employer shall ensure that all climbing equipment is inspected before each day's use to determine that it is in safe working condition.
Ladders, step bolts, and manhole steps shall meet the applicable requirements in subpart D of this part.
Head protection meeting the requirements of ANSI Z89.2-1971, “Safety Requirements for Industrial Protective Helmets for Electrical Workers, Class B” shall be provided whenever there is exposure to possible high voltage electrical contact, and the employer shall ensure that the head protection is used by employees. ANSI Z89.2-1971 is incorporated by reference as specified in § 1910.6.
Eye protection meeting the requirements of § 1910.133 (a)(2) thru (a)(6) shall be provided and the employer shall ensure its use by employees where foreign objects may enter the eyes due to work operations such as but not limited to:
Flame-type heaters may not be used within ground tents or on platforms within aerial tents unless:
Torches may be used on aerial splicing platforms or in buckets enclosed by tents provided the tent material is constructed of fire resistant material and the torch is turned off when not in actual use. Aerial tents shall be adequately ventilated while the torch is in operation.
Nominal 120V, or less, portable generators used for providing power at work locations do not require grounding if the output circuit is completely isolated from the frame of the unit.
Vehicle-mounted utility generators used for providing nominal 240V AC or less for powering portable tools and equipment need not be grounded to earth if all of the following conditions are met:
Grounding shall be omitted when using soldering irons, guns or wire-wrap tools on telecommunications circuits.
The wiping of lead joints using melted solder, gas fueled torches, soldering irons or other appropriate heating devices, and the soldering of wires or other electrical connections do not constitute the welding, cutting and brazing described in subpart Q of this part. When operated from commercial power the metal housing of electric solder pots shall be grounded. Electric solder pots may be used with the power equipment described in paragraph (i)(5) of this section without a grounding conductor. The employer shall ensure that wiping gloves or cloths and eye protection are used in lead wiping operations. A drip pan to catch hot lead drippings shall also be provided and used.
These devices shall not be operated with any conductive part of the equipment closer to exposed energized power lines than the clearances set forth in Table R-2 of this section.
When working with poles in piles or stacks, work shall be performed from the ends of the poles as much as possible, and precautions shall be taken for the safety of employees at the other end of the pole. During pole hauling operations, all loads shall be secured to prevent displacement. Lights, reflectors and/or flags shall be displayed on the end and sides of the load as necessary. The requirements for installation, removal, or other handling of poles in pole lines are prescribed in paragraph (n) of this section which pertains to overhead lines. In the case of hoisting machinery equipped with a positive stop loadholding device, it shall be permissible for the operator to leave his position at the controls (while a load is suspended) for the sole purpose of assisting in positioning the load prior to landing it. Prior to unloading steel, poles, crossarms, and similar material, the load shall be thoroughly examined to ascertain that the load has not shifted, that binders or stakes have not broken, and that the load is not otherwise hazardous to employees.
Cable reels in storage shall be checked or otherwise restrained when there is a possibility that they might accidentally roll from position.
Electric power conductors and equipment shall be considered as energized unless the employee can visually determine that they are bonded to one of the grounds listed in paragraph (m)(4) of this section.
Nonworking open wire communications lines shall be bonded to one of the grounds listed in paragraph (m)(4) of this section.
Acceptable grounds for protective grounding are as follows:
When attaching grounds (bonds), the first attachment shall be made to the protective ground. When removing bonds, the connection to the line or equipment shall be removed first. Insulating gloves shall be worn during these operations.
Unless temporary guys or braces are attached, the following poles shall be tested in accordance with paragraph (n)(3) of this section and determined to be safe before employees are permitted to climb them:
One of the following methods or an equivalent method shall be used for testing wood poles:
Poles or structures determined to be unsafe by test or observation may not be climbed until made safe by guying, bracing or other adequate means. Poles determined to be unsafe to climb shall, until they are made safe, be tagged in a conspicuous place to alert and warn all employees of the unsafe condition.
Where strand passes over electric power wires or railroad tracks, it shall be inspected from an elevated working position at each pole supporting the span in question. The strand may not be used to support any splicing platform, scaffold or cable car, if any of the following conditions exist:
Unless adequate railings are provided, safety straps and body belts shall be used while working on elevated work platforms such as aerial splicing platforms, pole platforms, ladder platforms and terminal balconies.
Safety straps and body belts shall be worn when working at elevated positions on poles, towers or similar structures, which do not have adequately guarded work areas.
Before installing or removing wire or cable, the pole or structure shall be guyed, braced, or otherwise supported, as necessary, to prevent failure of the pole or structure.
When cranes, derricks, or other mechanized equipment are used for setting, moving, or removing poles, all necessary precautions shall be taken to avoid contact with energized power conductors or equipment.
Climbing and working are prohibited above the level of the lowest electric power conducter on the pole (exclusive of vertical runs and street light wiring), except:
The provisions of this paragraph apply to the guarding of manholes and street openings, and to the ventilation and testing for gas in manholes and unvented vaults, where telecommunications field work is performed on or with underground lines.
While work is being performed in a manhole occupied jointly by an electric utility and a telecommunication utility, an employee with basic first aid training shall be available in the immediate vicinity to render emergency assistance as may be required. The employee whose presence is required in the immediate vicinity for the purposes of rendering emergency assistance is not to be precluded from occasionally entering a manhole to provide assistance other than in an emergency. The requirement of this paragraph (o)(3) does not preclude a qualified employee, working alone, from entering for brief periods of time, a manhole where energized cables or equipment are in service, for the purpose of inspection, housekeeping, taking readings, or similar work if such work can be performed safely.
Ladders shall be used to enter and exit manholes exceeding 4 feet in depth.
When open flames are used in manholes, the following precautions shall be taken to protect against the accumulation of combustible gas:
Employers shall insure that employees do not look into an open waveguide which is connected to an energized source of microwave radiation.
Accessible areas associated with microwave communication systems where the electromagnetic radiation level exceeds the radiation protection guide given in § 1910.97 shall be posted as described in that section. The lower half of the warning symbol shall include the following:
Radiation in this area may exceed hazard limitations and special precautions are required. Obtain specific instruction before entering.
When an employee works in an area where the electromagnetic radiation exceeds the radiation protection guide, the employer shall institute measures that insure that the employee's exposure is not greater than that permitted by the radiation guide. Such measures shall include, but not be limited to those of an administrative or engineering nature or those involving personal protective equipment.
electrical hazards —
| Voltage range (phase to phase) (kilovolts) | Minimum working distance |
|---|---|
| 2.1 to 15.0 | 2 ft. 0 in. |
| 15.1 to 35.0 | 2 ft. 4 in. |
| 35.1 to 46.0 | 2 ft. 6 in. |
| 46.1 to 72.5 | 3 ft. 0 in. |
| 72.6 to 121.0 | 3 ft. 4 in. |
| 138.0 to 145.0 | 3 ft. 6 in. |
| 161.0 to 169.0 | 3 ft. 8 in. |
| 230.0 to 242.0 | 5 ft. 0 in. |
| 345.0 to 362.0 | 7 ft. 0 in. |
| 500.0 to 552.0 | 11 ft. 0 in. |
| 700.0 to 765.0 | 15 ft. 0 in. |
Aerial lifts include the following types of vehicle-mounted aerial devices used to elevate personnel to jobsites above ground:
This consists of a platform, approximately 3 ft. × 4 ft., used to perform aerial cable work. It is furnished with fiber or synthetic ropes for supporting the platform from aerial strand, detachable guy ropes for anchoring it, and a device for raising and lowering it with a handline.
A small tent usually constructed of vinyl coated canvas which is usually supported by light metal or plastic tubing. It is designed to protect employees in inclement weather while working on ladders, aerial splicing platforms, or aerial devices.
Electrically connected to a source of potential difference, or electrically charged so as to have a potential significantly different from that of the earth in the vicinity. The term live is sometimes used in the place of the term current-carrying, where the intent is clear, to avoid repetition of the longer term.
A physical obstruction such as tapes, cones, or “A” frame type wood and/or metal structure intended to warn and limit access to a work area.
A physical obstruction which is intended to prevent contact with energized lines or equipment, or to prevent unauthorized access to work area.
An electrical connection from one conductive element to another for the purpose of minimizing potential differences or providing suitable conductivity for fault current or for mitigation of leakage current and electrolytic action.
A conductor with insulation, or a stranded conductor with or without insulation and other coverings (single-conductor cable), or a combination of conductors insulated from one another (multiple-conductor cable).
A protective covering applied to cables.
A conductor or system of conductors through which an electric current is intended to flow.
The conductors and their supporting or containing structures for telephone, telegraph, railroad signal, data, clock, fire, police-alarm, community television antenna and other systems which are used for public or private signal or communication service, and which operate at potentials not exceeding 400 volts to ground or 750 volts between any two points of the circuit, and the transmitted power of which does not exceed 150 watts. When communications lines operate at less than 150 volts to ground, no limit is placed on the capacity of the system. Specifically designed communications cables may include communication circuits not complying with the preceding limitations, where such circuits are also used incidentally to supply power to communication equipment.
A material, usually in the form of a wire, cable, or bus bar, suitable for carrying an electric current.
Intentionally connected to earth through a ground connection or connections of sufficiently low impedance and having sufficient current-carrying capacity to prevent the build-up of voltages which may result in undue hazard to connected equipment or to persons.
A general term which includes materials, fittings, devices, appliances, fixtures, apparatus, and similar items used as part of, or in connection with, a supply or communications installation.
That conductive body, usually earth, to which an electric potential is referenced.
A conductive connection, whether intentional or accidental, by which an electric circuit or equipment is connected to reference ground.
The connecting or establishment of a connection, whether by intention or accident, of an electric circuit or equipment to reference ground.
A small tent usually constructed of vinyl coated canvas supported by a metal or plastic frame. Its purpose is to protect employees from inclement weather while working at buried cable pedestal sites or similar locations.
A system or circuit conductor which is intentionally grounded.
A system of conductors in which at least one conductor or point (usually the middle wire, or the neutral point of transformer or generator windings) is intentionally grounded, either solidly or through a current-limiting device (not a current-interrupting device).
Separated from other conducting surfaces by a dielectric substance (including air space) offering a high resistance to the passage of current.
That which is relied upon to insulate the conductor from other conductors or conducting parts or from ground.
The sharing of a common facility, such as a manhole, trench or pole, by two or more different kinds of utilities (e.g., power and telecommunications).
A device designed to facilitate working aloft from an extension ladder. A typical device consists of a platform (approximately 9″ × 18″) hinged to a welded pipe frame. The rear edge of the platform and the bottom cross-member of the frame are equipped with latches to lock the platform to ladder rungs.
A removable seat used to facilitate work at an elevated position on rolling ladders in telecommunication centers.
A subsurface enclosure which personnel may enter and which is used for the purpose of installing, operating, and maintaining submersible equipment and/or cable.
A platform consisting of separate planks which are laid across steel platform supports. The ends of the supports are engaged in the manhole cable racks.
The act of communicating or signaling utilizing a frequency between 1 GH z (gigahertz) and 300 GH z inclusively.
The nominal voltage of a system or circuit is the value assigned to a system or circuit of a given voltage class for the purpose of convenient designation. The actual voltage may vary above or below this value.
A balcony or seat used as a support for workmen at pole-mounted equipment or terminal boxes. A typical device consists of a bolted assembly of steel details and a wooden platform. Steel braces run from the pole to the underside of the balcony. A guard rail (approximately 30″ high) may be provided.
A platform intended for use by a workman in splicing and maintenance operations in an elevated position adjacent to a pole. It consists of a platform equipped at one end with a hinged chain binder for securing the platform to a pole. A brace from the pole to the underside of the platform is also provided.
Any worker who by reason of his training and experience has demonstrated his ability to safely perform his duties.
A tree worker who through related training and on-the-job experience is familar with the special techniques and hazards involved in line clearance.
Any worker regularly assigned to a line-clearance tree-trimming crew and undergoing on-the-job training who, in the course of such training, has demonstrated his ability to perform his duties safely at his level of training.
The person or organization that operates or controls the electrical conductors involved.
An installation of communication equipment under the exclusive control of an organization providing telecommunications service, that is located outdoors or in a vault, chamber, or a building space used primarily for such installations.
Rotating or nonrotating derrick structures permanently mounted on vehicles for the purpose of lifting, lowering, or positioning hardware and materials used in telecommunications work.
A truck used to transport men, tools, and material, and to serve as a traveling workshop for telecommunication installation and maintenance work. It is sometimes equipped with a boom and auxiliary equipment for setting poles, digging holes, and elevating material or men.
The furnishing of a capability to signal or communicate at a distance by means such as telephone, telegraph, police and firealarm, community antenna television, or similar system, using wire, conventional cable, coaxial cable, wave guides, microwave transmission, or other similar means.
An enclosed vault in which the only openings are access openings.
An enclosure above or below ground which personnel may enter, and which is used for the purpose of installing, operating, and/or maintaining equipment and/or cable which need not be of submersible design.
An enclosure as described in paragraph(s) (42) of this section, with provision for air changes using exhaust flue stack(s) and low level air intake(s), operating on differentials of pressure and temperature providing for air flow.
The voltage between any conductor and ground unless otherwise indicated.
The voltage between any two conductors. If one circuit is directly connected to and supplied from another circuit of higher voltage (as in the case of an autotransformer), both are considered as of the higher voltage, unless the circuit of lower voltage is effectively grounded, in which case its voltage is not determined by the circuit of higher voltage. Direct connection implies electric connection as distinguished from connection merely through electromagnetic or electrostatic induction.
[40 FR 13441, Mar. 26, 1975, as amended at 43 FR 49751, Oct. 24, 1978; 47 FR 14706, Apr. 6, 1982; 52 FR 36387, Sept. 28, 1987; 54 FR 24334, June 7, 1989; 61 FR 9242, Mar. 7, 1996; 63 FR 33467, June 18, 1998; 67 FR 67965, Nov. 7, 2002; 69 FR 31882, June 8, 2004; 70 FR 1141, Jan. 5, 2005; 81 FR 83006, Nov. 18, 2016]
Existing characteristics and conditions of electric lines and equipment that are related to the safety of the work to be performed shall be determined before work on or near the lines or equipment is started. Such characteristics and conditions include, but are not limited to:
The employer shall provide medical services and first aid as required in § 1910.151. In addition to the requirements of § 1910.151, the following requirements also apply:
When employees are performing work on, or associated with, exposed lines or equipment energized at 50 volts or more, persons with first-aid training shall be available as follows:
First-aid supplies required by § 1910.151(b) shall be placed in weatherproof containers if the supplies could be exposed to the weather.
The employer shall maintain each first-aid kit, shall ensure that it is readily available for use, and shall inspect it frequently enough to ensure that expended items are replaced. The employer also shall inspect each first aid kit at least once per year.
The briefing shall cover at least the following subjects: hazards associated with the job, work procedures involved, special precautions, energy-source controls, and personal protective equipment requirements.
An employee working alone need not conduct a job briefing. However, the employer shall ensure that the tasks to be performed are planned as if a briefing were required.
The provisions of paragraph (d) of this section apply to the use of lockout/tagout procedures for the control of energy sources in installations for the purpose of electric power generation, including related equipment for communication or metering. Locking and tagging procedures for the deenergizing of electric energy sources which are used exclusively for purposes of transmission and distribution are addressed by paragraph (m) of this section.
Lockout and tagout device application and removal may only be performed by the authorized employees who are performing the servicing or maintenance.
Affected employees shall be notified by the employer or authorized employee of the application and removal of lockout or tagout devices. Notification shall be given before the controls are applied and after they are removed from the machine or equipment.
The established procedures for the application of energy control (the lockout or tagout procedures) shall include the following elements and actions, and these procedures shall be performed in the following sequence:
Before lockout or tagout devices are removed and energy is restored to the machine or equipment, procedures shall be followed and actions taken by the authorized employees to ensure the following:
This paragraph covers enclosed spaces that may be entered by employees. It does not apply to vented vaults if the employer makes a determination that the ventilation system is operating to protect employees before they enter the space. This paragraph applies to routine entry into enclosed spaces in lieu of the permit-space entry requirements contained in paragraphs (d) through (k) of § 1910.146. If, after the employer takes the precautions given in paragraphs (e) and (t) of this section, the hazards remaining in the enclosed space endanger the life of an entrant or could interfere with an entrant's escape from the space, then entry into the enclosed space shall meet the permit-space entry requirements of paragraphs (d) through (k) of § 1910.146.
The employer shall ensure the use of safe work practices for entry into, and work in, enclosed spaces and for rescue of employees from such spaces.
Each employee who enters an enclosed space or who serves as an attendant shall be trained in the hazards of enclosed-space entry, in enclosed-space entry procedures, and in enclosed-space rescue procedures.
Employers shall provide equipment to ensure the prompt and safe rescue of employees from the enclosed space.
Before any entrance cover to an enclosed space is removed, the employer shall determine whether it is safe to do so by checking for the presence of any atmospheric pressure or temperature differences and by evaluating whether there might be a hazardous atmosphere in the space. Any conditions making it unsafe to remove the cover shall be eliminated before the cover is removed.
When covers are removed from enclosed spaces, the opening shall be promptly guarded by a railing, temporary cover, or other barrier designed to prevent an accidental fall through the opening and to protect employees working in the space from objects entering the space.
Employees may not enter any enclosed space while it contains a hazardous atmosphere, unless the entry conforms to the permit-required confined spaces standard in § 1910.146.
While work is being performed in the enclosed space, an attendant with first-aid training shall be immediately available outside the enclosed space to provide assistance if a hazard exists because of traffic patterns in the area of the opening used for entry. The attendant is not precluded from performing other duties outside the enclosed space if these duties do not distract the attendant from: monitoring employees within the space or ensuring that it is safe for employees to enter and exit the space.
Test instruments used to monitor atmospheres in enclosed spaces shall be kept in calibration and shall have a minimum accuracy of ±10 percent.
Before an employee enters an enclosed space, the atmosphere in the enclosed space shall be tested for oxygen deficiency with a direct-reading meter or similar instrument, capable of collection and immediate analysis of data samples without the need for off-site evaluation. If continuous forced-air ventilation is provided, testing is not required provided that the procedures used ensure that employees are not exposed to the hazards posed by oxygen deficiency.
Before an employee enters an enclosed space, the internal atmosphere shall be tested for flammable gases and vapors with a direct-reading meter or similar instrument capable of collection and immediate analysis of data samples without the need for off-site evaluation. This test shall be performed after the oxygen testing and ventilation required by paragraph (e)(9) of this section demonstrate that there is sufficient oxygen to ensure the accuracy of the test for flammability.
If continuous forced-air ventilation is used, it shall begin before entry is made and shall be maintained long enough for the employer to be able to demonstrate that a safe atmosphere exists before employees are allowed to enter the work area. The forced-air ventilation shall be so directed as to ventilate the immediate area where employees are present within the enclosed space and shall continue until all employees leave the enclosed space.
The air supply for the continuous forced-air ventilation shall be from a clean source and may not increase the hazards in the enclosed space.
If open flames are used in enclosed spaces, a test for flammable gases and vapors shall be made immediately before the open flame device is used and at least once per hour while the device is used in the space. Testing shall be conducted more frequently if conditions present in the enclosed space indicate that once per hour is insufficient to detect hazardous accumulations of flammable gases or vapors.
Excavation operations shall comply with subpart P of part 1926 of this chapter.
Personal protective equipment shall meet the requirements of subpart I of this part.
| Test method | Criteria for passing the test |
|---|---|
| Vertically suspend a 500-mm (19.7-inch) length of strapping supporting a 100-kg (220.5-lb) weight Use a butane or propane burner with a 76-mm (3-inch) flame. | Any flames on the positioning strap shall self extinguish. The positioning strap shall continue to support the 100-kg (220.5-lb) mass. |
| Direct the flame to an edge of the strapping at a distance of 25 mm (1 inch) | |
| Remove the flame after 5 seconds | |
| Wait for any flames on the positioning strap to stop burning |
Requirements for portable ladders contained in subpart D of this part apply in addition to the requirements of paragraph (h) of this section, except as specifically noted in paragraph (h)(2) of this section.
Portable ladders used on structures or conductors in conjunction with overhead line work need not meet § 1910.23(c)(4) and (9). Portable ladders and platforms used on structures or conductors in conjunction with overhead line work shall meet the following requirements:
Portable metal ladders and other portable conductive ladders may not be used near exposed energized lines or equipment. However, in specialized high-voltage work, conductive ladders shall be used when the employer demonstrates that nonconductive ladders would present a greater hazard to employees than conductive ladders.
Paragraph (i)(2) of this section applies to electric equipment connected by cord and plug. Paragraph (i)(3) of this section applies to portable and vehicle-mounted generators used to supply cord- and plug-connected equipment. Paragraph (i)(4) of this section applies to hydraulic and pneumatic tools.
Cord- and plug-connected equipment not covered by subpart S of this part shall comply with one of the following instead of § 1910.243(a)(5):
Portable and vehicle-mounted generators used to supply cord- and plug-connected equipment covered by paragraph (i)(2) of this section shall meet the following requirements:
Live-line tool rods, tubes, and poles shall be designed and constructed to withstand the following minimum tests:
Materials handling and storage shall comply with applicable material-handling and material-storage requirements in this part, including those in subpart N of this part.
This paragraph applies to work on exposed live parts, or near enough to them to expose the employee to any hazard they present.
The employer shall ensure that employees make connections as follows:
When an employee performs work within reaching distance of exposed energized parts of equipment, the employer shall ensure that the employee removes or renders nonconductive all exposed conductive articles, such as keychains or watch chains, rings, or wrist watches or bands, unless such articles do not increase the hazards associated with contact with the energized parts.
When an employee must install or remove fuses with one or both terminals energized at more than 300 volts, or with exposed parts energized at more than 50 volts, the employer shall ensure that the employee uses tools or gloves rated for the voltage. When an employee installs or removes expulsion-type fuses with one or both terminals energized at more than 300 volts, the employer shall ensure that the employee wears eye protection meeting the requirements of subpart I of this part, uses a tool rated for the voltage, and is clear of the exhaust path of the fuse barrel.
The requirements of this section that pertain to the hazards of exposed live parts also apply when an employee performs work in proximity to covered (noninsulated) wires.
Non-current-carrying metal parts of equipment or devices, such as transformer cases and circuit-breaker housings, shall be treated as energized at the highest voltage to which these parts are exposed, unless the employer inspects the installation and determines that these parts are grounded before employees begin performing the work.
| For phase-to-phase system voltages of 50 V to 300 V: 1 | |
|---|---|
| MAD = avoid contact | |
| For phase-to-phase system voltages of 301 V to 5 kV: 1 | |
| MAD = M + D, where | |
| D = 0.02 m | the electrical component of the minimum approach distance. |
| M = 0.31 m for voltages up to 750 V and 0.61 m otherwise | the inadvertent movement factor. |
| For phase-to-phase system voltages of 5.1 kV to 72.5 kV: 1 4 | |
| MAD = M + AD, where | |
| M = 0.61 m | the inadvertent movement factor. |
| A = the applicable value from Table R-5 | the altitude correction factor. |
| D = the value from Table R-4 corresponding to the voltage and exposure or the value of the electrical component of the minimum approach distance calculated using the method provided in appendix B to this section | the electrical component of the minimum approach distance. |
| For phase-to-phase system voltages of more than 72.5 kV, nominal: 2 4 | |
| MAD = 0.3048( C + a ) V L-G TA + M | |
| C = 0.01 for phase-to-ground exposures that the employer can demonstrate consist only of air across the approach distance (gap), | |
| 0.01 for phase-to-phase exposures if the employer can demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap, or | |
| 0.011 otherwise | |
| V L-G = phase-to-ground rms voltage, in kV | |
| T = maximum anticipated per-unit transient overvoltage; for phase-to-ground exposures, T equals T L-G , the maximum per-unit transient overvoltage, phase-to-ground, determined by the employer under paragraph (l)(3)(ii) of this section; for phase-to-phase exposures, T equals 1.35 T L-G + 0.45 | |
| A = altitude correction factor from Table R-5 | |
| M = 0.31 m, the inadvertent movement factor | |
| a = saturation factor, as follows: |
| Phase-to-Ground Exposures | |||||
|---|---|---|---|---|---|
| V Peak = T L-G V L-G √2 | 635 kV or less | 635.1 to 915 kV | 915.1 to 1,050 kV | More than 1,050 kV | |
| a | 0 | ( V Peak -635)/140,000 | ( V Peak -645)/135,000 | ( V Peak -675)/125,000 | |
| Phase-to-Phase Exposures 3 | |||||
| V Peak = (1.35 T L-G + 0.45) V L-G √2 | 630 kV or less | 630.1 to 848 kV | 848.1 to 1,131 kV | 1,131.1 to 1,485 kV | More than 1,485 kV |
| a | 0 | ( V Peak -630)/155,000 | ( V Peak -633.6)/152,207 | ( V Peak -628)/153,846 | ( V Peak -350.5)/203,666 |
| 1 Employers may use the minimum approach distances in Table R-6. If the worksite is at an elevation of more than 900 meters (3,000 feet), see footnote 1 to Table R-6. | |||||
| 2 Employers may use the minimum approach distances in Table R-7, except that the employer may not use the minimum approach distances in Table R-7 for phase-to-phase exposures if an insulated tool spans the gap or if any large conductive object is in the gap. If the worksite is at an elevation of more than 900 meters (3,000 feet), see footnote 1 to Table R-7. Employers may use the minimum approach distances in Table 14 through Table 21 in appendix B to this section, which calculated MAD for various values of T, provided the employer follows the notes to those tables. | |||||
| 3 Use the equations for phase-to-ground exposures (with V Peak for phase-to-phase exposures) unless the employer can demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap. | |||||
| 4 Until March 31, 2015, employers may use the minimum approach distances in Table 6 through Table 13 in Appendix B to this section. |
| Nominal voltage (kV) phase-to-phase | Phase-to-ground exposure | Phase-to-phase exposure |
|---|---|---|
| D (m) | D (m) | |
| 5.1 to 15.0 | 0.04 | 0.07 |
| 15.1 to 36.0 | 0.16 | 0.28 |
| 36.1 to 46.0 | 0.23 | 0.37 |
| 46.1 to 72.5 | 0.39 | 0.59 |
| Altitude above sea level (m) | A |
|---|---|
| 0 to 900 | 1.00 |
| 901 to 1,200 | 1.02 |
| 1,201 to 1,500 | 1.05 |
| 1,501 to 1,800 | 1.08 |
| 1,801 to 2,100 | 1.11 |
| 2,101 to 2,400 | 1.14 |
| 2,401 to 2,700 | 1.17 |
| 2,701 to 3,000 | 1.20 |
| 3,001 to 3,600 | 1.25 |
| 3,601 to 4,200 | 1.30 |
| 4,201 to 4,800 | 1.35 |
| 4,801 to 5,400 | 1.39 |
| 5,401 to 6,000 | 1.44 |
| Nominal voltage (kV) phase-to-phase | Distance | |||
|---|---|---|---|---|
| Phase-to-ground exposure | Phase-to-phase exposure | |||
| m | ft | m | ft | |
| 0.050 to 0.300 2 | Avoid Contact | Avoid Contact | ||
| 0.301 to 0.750 2 | 0.33 | 1.09 | 0.33 | 1.09 |
| 0.751 to 5.0 | 0.63 | 2.07 | 0.63 | 2.07 |
| 5.1 to 15.0 | 0.65 | 2.14 | 0.68 | 2.24 |
| 15.1 to 36.0 | 0.77 | 2.53 | 0.89 | 2.92 |
| 36.1 to 46.0 | 0.84 | 2.76 | 0.98 | 3.22 |
| 46.1 to 72.5 | 1.00 | 3.29 | 1.20 | 3.94 |
| 1 Employers may use the minimum approach distances in this table provided the worksite is at an elevation of 900 meters (3,000 feet) or less. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table R-5 corresponding to the altitude of the work. | ||||
| 2 For single-phase systems, use voltage-to-ground. |
| Voltage range phase to phase (kV) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 72.6 to 121.0 | 1.13 | 3.71 | 1.42 | 4.66 |
| 121.1 to 145.0 | 1.30 | 4.27 | 1.64 | 5.38 |
| 145.1 to 169.0 | 1.46 | 4.79 | 1.94 | 6.36 |
| 169.1 to 242.0 | 2.01 | 6.59 | 3.08 | 10.10 |
| 242.1 to 362.0 | 3.41 | 11.19 | 5.52 | 18.11 |
| 362.1 to 420.0 | 4.25 | 13.94 | 6.81 | 22.34 |
| 420.1 to 550.0 | 5.07 | 16.63 | 8.24 | 27.03 |
| 550.1 to 800.0 | 6.88 | 22.57 | 11.38 | 37.34 |
| 1 Employers may use the minimum approach distances in this table provided the worksite is at an elevation of 900 meters (3,000 feet) or less. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table R-5 corresponding to the altitude of the work. | ||||
| 2 Employers may use the phase-to-phase minimum approach distances in this table provided that no insulated tool spans the gap and no large conductive object is in the gap. | ||||
| 3 The clear live-line tool distance shall equal or exceed the values for the indicated voltage ranges. |
| Maximum anticipated per-unit transient overvoltage | Distance (m) maximum line-to-ground voltage (kV) | ||||
|---|---|---|---|---|---|
| 250 | 400 | 500 | 600 | 750 | |
| 1.5 or less | 1.12 | 1.60 | 2.06 | 2.62 | 3.61 |
| 1.6 | 1.17 | 1.69 | 2.24 | 2.86 | 3.98 |
| 1.7 | 1.23 | 1.82 | 2.42 | 3.12 | 4.37 |
| 1.8 | 1.28 | 1.95 | 2.62 | 3.39 | 4.79 |
| 1 The distances specified in this table are for air, bare-hand, and live-line tool conditions. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table R-5 corresponding to the altitude of the work. |
| Voltage range (kV) | Type of current (ac or dc) | Assumed maximum per-unit transient overvoltage |
|---|---|---|
| 72.6 to 420.0 | ac | 3.5 |
| 420.1 to 550.0 | ac | 3.0 |
| 550.1 to 800.0 | ac | 2.5 |
| 250 to 750 | dc | 1.8 |
Paragraph (m) of this section applies to the deenergizing of transmission and distribution lines and equipment for the purpose of protecting employees. See paragraph (d) of this section for requirements on the control of hazardous energy sources used in the generation of electric energy. Conductors and parts of electric equipment that have been deenergized under procedures other than those required by paragraph (d) or (m) of this section, as applicable, shall be treated as energized.
Paragraph (n) of this section applies to grounding of generation, transmission, and distribution lines and equipment for the purpose of protecting employees. Paragraph (n)(4) of this section also applies to protective grounding of other equipment as required elsewhere in this section.
For any employee to work transmission and distribution lines or equipment as deenergized, the employer shall ensure that the lines or equipment are deenergized under the provisions of paragraph (m) of this section and shall ensure proper grounding of the lines or equipment as specified in paragraphs (n)(3) through (n)(8) of this section. However, if the employer can demonstrate that installation of a ground is impracticable or that the conditions resulting from the installation of a ground would present greater hazards to employees than working without grounds, the lines and equipment may be treated as deenergized provided that the employer establishes that all of the following conditions apply:
Temporary protective grounds shall be placed at such locations and arranged in such a manner that the employer can demonstrate will prevent each employee from being exposed to hazardous differences in electric potential.
The employer shall ensure that, unless a previously installed ground is present, employees test lines and equipment and verify the absence of nominal voltage before employees install any ground on those lines or that equipment.
The employer shall ensure that, when an employee performs work on a cable at a location remote from the cable terminal, the cable is not grounded at the cable terminal if there is a possibility of hazardous transfer of potential should a fault occur.
The employer may permit employees to remove grounds temporarily during tests. During the test procedure, the employer shall ensure that each employee uses insulating equipment, shall isolate each employee from any hazards involved, and shall implement any additional measures necessary to protect each exposed employee in case the previously grounded lines and equipment become energized.
Paragraph (o) of this section provides for safe work practices for high-voltage and high-power testing performed in laboratories, shops, and substations, and in the field and on electric transmission and distribution lines and equipment. It applies only to testing involving interim measurements using high voltage, high power, or combinations of high voltage and high power, and not to testing involving continuous measurements as in routine metering, relaying, and normal line work.
Mechanical equipment used to lift or move lines or other material shall be used within its maximum load rating and other design limitations for the conditions under which the mechanical equipment is being used.
This paragraph provides additional requirements for work performed on or near overhead lines and equipment and for live-line barehand work.
The following provisions apply to the installation and removal of overhead conductors or cable (overhead lines).
In addition to other applicable provisions contained in this section, the following requirements apply to live-line barehand work:
The following requirements apply to work performed on towers or other structures that support overhead lines.
This paragraph provides additional requirements for line-clearance tree trimming and for equipment used in this type of work.
This paragraph does not apply to qualified employees.
Gasoline-engine power saw operations shall meet the requirements of § 1910.266(e) and the following:
Each employee shall be tied in with a climbing rope and safety saddle when the employee is working above the ground in a tree, unless he or she is ascending into the tree.
The employer shall ensure that employees perform power-line carrier work, including work on equipment used for coupling carrier current to power line conductors, in accordance with the requirements of this section pertaining to work on energized lines.
This paragraph provides additional requirements for work on underground electrical installations.
The employer shall ensure that employees use a ladder or other climbing device to enter and exit a manhole or subsurface vault exceeding 1.22 meters (4 feet) in depth. No employee may climb into or out of a manhole or vault by stepping on cables or hangers.
The employer shall ensure that, if employees use duct rods, the employees install the duct rods in the direction presenting the least hazard to employees. The employer shall station an employee at the far end of the duct line being rodded to ensure that the employees maintain the required minimum approach distances.
When multiple cables are present in a work area, the employer shall identify the cable to be worked by electrical means, unless its identity is obvious by reason of distinctive appearance or location or by other readily apparent means of identification. The employer shall protect cables other than the one being worked from damage.
Except when paragraph (t)(7)(ii) of this section permits employees to perform work that could cause a fault in an energized cable in a manhole or vault, the employer shall ensure that employees inspect energized cables to be moved for abnormalities.
When employees perform work on buried cable or on cable in a manhole or vault, the employer shall maintain metallic-sheath continuity, or the cable sheath shall be treated as energized.
This paragraph provides additional requirements for substations and for work performed in them.
The employer shall provide and maintain sufficient access and working space about electric equipment to permit ready and safe operation and maintenance of such equipment by employees.
The employer shall ensure that, when employees remove or insert draw-out-type circuit breakers, the breaker is in the open position. The employer shall also render the control circuit inoperable if the design of the equipment permits.
Conductive fences around substations shall be grounded. When a substation fence is expanded or a section is removed, fence sections shall be isolated, grounded, or bonded as necessary to protect employees from hazardous differences in electric potential.
This paragraph provides additional requirements and related work practices for power generating plants.
Before exciter or generator brushes are changed while the generator is in service, the exciter or generator field shall be checked to determine whether a ground condition exists. The brushes may not be changed while the generator is energized if a ground condition exists.
The employer shall provide and maintain sufficient access and working space about electric equipment to permit ready and safe operation and maintenance of such equipment by employees.
The following requirements apply to work in water and steam spaces associated with boilers:
The following requirements apply to chemical cleaning of boilers and pressure vessels:
Additionally, the number of personnel shall be limited to those necessary to accomplish the task safely.
Employees working on or close to water gates, valves, intakes, forebays, flumes, or other locations where increased or decreased water flow or levels may pose a significant hazard shall be warned and shall vacate such dangerous areas before water flow changes are made.
The following additional requirements apply to work on capacitors and on lines connected to capacitors.
The employer shall ensure that employees do not open the secondary of a current transformer while the transformer is energized. If the employer cannot deenergize the primary of the current transformer before employees perform work on an instrument, a relay, or other section of a current transformer secondary circuit, the employer shall bridge the circuit so that the current transformer secondary does not experience an open-circuit condition.
The employer shall provide sufficient illumination to enable the employee to perform the work safely.
When there is a possibility of voltage backfeed from sources of cogeneration or from the secondary system (for example, backfeed from more than one energized phase feeding a common load), the requirements of paragraph (l) of this section apply if employees will work the lines or equipment as energized, and the requirements of paragraphs (m) and (n) of this section apply if employees will work the lines or equipment as deenergized.
The employer shall install, adjust, and operate laser equipment in accordance with § 1926.54 of this chapter.
Hydraulic fluids used for the insulated sections of equipment shall provide insulation for the voltage involved.
Affected employee. An employee whose job requires him or her to operate or use a machine or equipment on which servicing or maintenance is being performed under lockout or tagout, or whose job requires him or her to work in an area in which such servicing or maintenance is being performed.
Attendant. An employee assigned to remain immediately outside the entrance to an enclosed or other space to render assistance as needed to employees inside the space.
Authorized employee. An employee who locks out or tags out machines or equipment in order to perform servicing or maintenance on that machine or equipment. An affected employee becomes an authorized employee when that employee's duties include performing servicing or maintenance covered under this section.
Automatic circuit recloser. A self-controlled device for automatically interrupting and reclosing an alternating-current circuit, with a predetermined sequence of opening and reclosing followed by resetting, hold closed, or lockout.
Barricade. A physical obstruction such as tapes, cones, or A-frame type wood or metal structures that provides a warning about, and limits access to, a hazardous area.
Barrier. A physical obstruction that prevents contact with energized lines or equipment or prevents unauthorized access to a work area.
Bond. The electrical interconnection of conductive parts designed to maintain a common electric potential.
Bus. A conductor or a group of conductors that serve as a common connection for two or more circuits.
Bushing. An insulating structure that includes a through conductor or that provides a passageway for such a conductor, and that, when mounted on a barrier, insulates the conductor from the barrier for the purpose of conducting current from one side of the barrier to the other.
Cable. A conductor with insulation, or a stranded conductor with or without insulation and other coverings (single-conductor cable), or a combination of conductors insulated from one another (multiple-conductor cable).
Cable sheath. A conductive protective covering applied to cables.
Circuit. A conductor or system of conductors through which an electric current is intended to flow.
Clearance (between objects). The clear distance between two objects measured surface to surface.
Clearance (for work). Authorization to perform specified work or permission to enter a restricted area.
Communication lines. (See Lines; (1) Communication lines. )
Conductor. A material, usually in the form of a wire, cable, or bus bar, used for carrying an electric current.
Contract employer. An employer, other than a host employer, that performs work covered by this section under contract.
Covered conductor. A conductor covered with a dielectric having no rated insulating strength or having a rated insulating strength less than the voltage of the circuit in which the conductor is used.
Current-carrying part. A conducting part intended to be connected in an electric circuit to a source of voltage. Non-current-carrying parts are those not intended to be so connected.
Deenergized. Free from any electrical connection to a source of potential difference and from electric charge; not having a potential that is different from the potential of the earth.
Designated employee (designated person). An employee (or person) who is assigned by the employer to perform specific duties under the terms of this section and who has sufficient knowledge of the construction and operation of the equipment, and the hazards involved, to perform his or her duties safely.
Electric line truck. A truck used to transport personnel, tools, and material for electric supply line work.
Electric supply equipment. Equipment that produces, modifies, regulates, controls, or safeguards a supply of electric energy.
Electric supply lines. (See Lines; (2) Electric supply lines. )
Electric utility. An organization responsible for the installation, operation, or maintenance of an electric supply system.
Enclosed space. A working space, such as a manhole, vault, tunnel, or shaft, that has a limited means of egress or entry, that is designed for periodic employee entry under normal operating conditions, and that, under normal conditions, does not contain a hazardous atmosphere, but may contain a hazardous atmosphere under abnormal conditions.
Energized (alive, live). Electrically connected to a source of potential difference, or electrically charged so as to have a potential significantly different from that of earth in the vicinity.
Energy isolating device. A physical device that prevents the transmission or release of energy, including, but not limited to, the following: a manually operated electric circuit breaker, a disconnect switch, a manually operated switch, a slide gate, a slip blind, a line valve, blocks, and any similar device with a visible indication of the position of the device. (Push buttons, selector switches, and other control-circuit-type devices are not energy isolating devices.)
Energy source. Any electrical, mechanical, hydraulic, pneumatic, chemical, nuclear, thermal, or other energy source that could cause injury to employees.
Entry (as used in paragraph (e) of this section). The action by which a person passes through an opening into an enclosed space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant's body breaks the plane of an opening into the space.
Equipment (electric). A general term including material, fittings, devices, appliances, fixtures, apparatus, and the like used as part of or in connection with an electrical installation.
Exposed, Exposed to contact (as applied to energized parts). Not isolated or guarded.
Fall restraint system. A fall protection system that prevents the user from falling any distance.
First-aid training. Training in the initial care, including cardiopulmonary resuscitation (which includes chest compressions, rescue breathing, and, as appropriate, other heart and lung resuscitation techniques), performed by a person who is not a medical practitioner, of a sick or injured person until definitive medical treatment can be administered.
Ground. A conducting connection, whether planned or unplanned, between an electric circuit or equipment and the earth, or to some conducting body that serves in place of the earth.
Grounded. Connected to earth or to some conducting body that serves in place of the earth.
Guarded. Covered, fenced, enclosed, or otherwise protected, by means of suitable covers or casings, barrier rails or screens, mats, or platforms, designed to minimize the possibility, under normal conditions, of dangerous approach or inadvertent contact by persons or objects.
Hazardous atmosphere. An atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue (that is, escape unaided from an enclosed space), injury, or acute illness from one or more of the following causes:
High-power tests. Tests in which the employer uses fault currents, load currents, magnetizing currents, and line-dropping currents to test equipment, either at the equipment's rated voltage or at lower voltages.
High-voltage tests. Tests in which the employer uses voltages of approximately 1,000 volts as a practical minimum and in which the voltage source has sufficient energy to cause injury.
High wind. A wind of such velocity that one or more of the following hazards would be present:
Host employer. An employer that operates, or that controls the operating procedures for, an electric power generation, transmission, or distribution installation on which a contract employer is performing work covered by this section.
Immediately dangerous to life or health (IDLH). Any condition that poses an immediate or delayed threat to life or that would cause irreversible adverse health effects or that would interfere with an individual's ability to escape unaided from a permit space.
Insulated. Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current.
Insulation (cable). Material relied upon to insulate the conductor from other conductors or conducting parts or from ground.
Isolated. Not readily accessible to persons unless special means for access are used.
Line-clearance tree trimmer. An employee who, through related training or on-the-job experience or both, is familiar with the special techniques and hazards involved in line-clearance tree trimming.
Line-clearance tree trimming. The pruning, trimming, repairing, maintaining, removing, or clearing of trees, or the cutting of brush, that is within the following distance of electric supply lines and equipment:
Lines —
The conductors and their supporting or containing structures which are used for public or private signal or communication service, and which operate at potentials not exceeding 400 volts to ground or 750 volts between any two points of the circuit, and the transmitted power of which does not exceed 150 watts. If the lines are operating at less than 150 volts, no limit is placed on the transmitted power of the system. Under certain conditions, communication cables may include communication circuits exceeding these limitations where such circuits are also used to supply power solely to communication equipment.
Conductors used to transmit electric energy and their necessary supporting or containing structures. Signal lines of more than 400 volts are always supply lines within this section, and those of less than 400 volts are considered as supply lines, if so run and operated throughout.
Manhole. A subsurface enclosure that personnel may enter and that is used for installing, operating, and maintaining submersible equipment or cable.
Minimum approach distance. The closest distance an employee may approach an energized or a grounded object.
Personal fall arrest system. A system used to arrest an employee in a fall from a working level.
Qualified employee (qualified person). An employee (person) knowledgeable in the construction and operation of the electric power generation, transmission, and distribution equipment involved, along with the associated hazards.
Statistical sparkover voltage. A transient overvoltage level that produces a 97.72-percent probability of sparkover (that is, two standard deviations above the voltage at which there is a 50-percent probability of sparkover).
Statistical withstand voltage. A transient overvoltage level that produces a 0.14-percent probability of sparkover (that is, three standard deviations below the voltage at which there is a 50-percent probability of sparkover).
Switch. A device for opening and closing or for changing the connection of a circuit. In this section, a switch is manually operable, unless otherwise stated.
System operator. A qualified person designated to operate the system or its parts.
Vault. An enclosure, above or below ground, that personnel may enter and that is used for installing, operating, or maintaining equipment or cable.
Vented vault. A vault that has provision for air changes using exhaust-flue stacks and low-level air intakes operating on pressure and temperature differentials that provide for airflow that precludes a hazardous atmosphere from developing.
Voltage. The effective (root mean square, or rms) potential difference between any two conductors or between a conductor and ground. This section expresses voltages in nominal values, unless otherwise indicated. The nominal voltage of a system or circuit is the value assigned to a system or circuit of a given voltage class for the purpose of convenient designation. The operating voltage of the system may vary above or below this value.
Work-positioning equipment. A body belt or body harness system rigged to allow an employee to be supported on an elevated vertical surface, such as a utility pole or tower leg, and work with both hands free while leaning.
Appendix A to § 1910.269—Flow Charts
This appendix presents information, in the form of flow charts, that illustrates the scope and application of § 1910.269. This appendix addresses the interface between § 1910.269 and Subpart S of this Part (Electrical), between § 1910.269 and § 1910.146 (Permit-required confined spaces), and between § 1910.269 and § 1910.147 (The control of hazardous energy (lockout/tagout)). These flow charts provide guidance for employers trying to implement the requirements of § 1910.269 in combination with other General Industry Standards contained in Part 1910. Employers should always consult the relevant standards, in conjunction with this appendix, to ensure compliance with all applicable requirements.
Appendix A-2 to § 1910.269—Application of § 1910.269 and Subpart S of this Part to Electrical Safety-Related Work Practices 1
| Compliance with Subpart S will comply with these paragraphs of § 1910.269 1 | Paragraphs that apply regardless of compliance with Subpart S 2 |
|---|---|
| (d), electric-shock hazards only | (a)(2), (a)(3) and (a)(4). |
| (h)(3) | (b) |
| (i)(2) and (i)(3) | (c) |
| (k) | (d), for other than electric-shock hazards. |
| (l)(1) through (l)(5), (l)(7), and (l)(10) through (l)(12) | (e) |
| (m) | (f) |
| (p)(4) | (g) |
| (s)(2) | (h)(1) and (h)(2). |
| (u)(1) and (u)(3) through (u)(5) | (i)(4) |
| (v)(3) through (v)(5) | (j) |
| (w)(1) and (w)(7) | (l)(6), (l)(8) and (l)(9). |
| (n) | |
| (o) | |
| (p)(1) through (p)(3). | |
| (q) | |
| (r) | |
| (s)(1) | |
| (t) | |
| (u)(2) and (u)(6) | |
| (v)(1), (v)(2), and (v)(6) through (v)(12). | |
| (w)(2) through (w)(6), (w)(8), and (w)(9). | |
| 1 If the electrical installation meets the requirements of §§ 1910.302 through 1910.308 of this part, then the electrical installation and any associated electrical safety-related work practices conforming to §§ 1910.332 through 1910.335 of this part are considered to comply with these provisions of § 1910.269 of this part. | |
| 2 These provisions include electrical safety and other requirements that must be met regardless of compliance with subpart S of this part. |
Appendix B to § 1910.269—Working on Exposed Energized Parts
I. Introduction
Electric utilities design electric power generation, transmission, and distribution installations to meet National Electrical Safety Code (NESC), ANSI C2, requirements. Electric utilities also design transmission and distribution lines to limit line outages as required by system reliability criteria 1 and to withstand the maximum overvoltages impressed on the system. Conditions such as switching surges, faults, and lightning can cause overvoltages. Electric utilities generally select insulator design and lengths and the clearances to structural parts so as to prevent outages from contaminated line insulation and during storms. Line insulator lengths and structural clearances have, over the years, come closer to the minimum approach distances used by workers. As minimum approach distances and structural clearances converge, it is increasingly important that system designers and system operating and maintenance personnel understand the concepts underlying minimum approach distances.
1 Federal, State, and local regulatory bodies and electric utilities set reliability requirements that limit the number and duration of system outages.
The information in this appendix will assist employers in complying with the minimum approach-distance requirements contained in § 1910.269(l)(3) and (q)(3). Employers must use the technical criteria and methodology presented in this appendix in establishing minimum approach distances in accordance with § 1910.269(l)(3)(i) and Table R-3 and Table R-8. This appendix provides essential background information and technical criteria for the calculation of the required minimum approach distances for live-line work on electric power generation, transmission, and distribution installations.
Unless an employer is using the maximum transient overvoltages specified in Table R-9 for voltages over 72.5 kilovolts, the employer must use persons knowledgeable in the techniques discussed in this appendix, and competent in the field of electric transmission and distribution system design, to determine the maximum transient overvoltage.
II. General
A. Definitions. The following definitions from § 1910.269(x) relate to work on or near electric power generation, transmission, and distribution lines and equipment and the electrical hazards they present.
Exposed.... Not isolated or guarded.
Guarded. Covered, fenced, enclosed, or otherwise protected, by means of suitable covers or casings, barrier rails or screens, mats, or platforms, designed to minimize the possibility, under normal conditions, of dangerous approach or inadvertent contact by persons or objects.
Insulated. Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current.
Isolated. Not readily accessible to persons unless special means for access are used.
Statistical sparkover voltage. A transient overvoltage level that produces a 97.72-percent probability of sparkover (that is, two standard deviations above the voltage at which there is a 50-percent probability of sparkover).
Statistical withstand voltage. A transient overvoltage level that produces a 0.14-percent probability of sparkover (that is, three standard deviations below the voltage at which there is a 50-percent probability of sparkover).
B. Installations energized at 50 to 300 volts. The hazards posed by installations energized at 50 to 300 volts are the same as those found in many other workplaces. That is not to say that there is no hazard, but the complexity of electrical protection required does not compare to that required for high-voltage systems. The employee must avoid contact with the exposed parts, and the protective equipment used (such as rubber insulating gloves) must provide insulation for the voltages involved.
C. Exposed energized parts over 300 volts AC. Paragraph (l)(3)(i) of § 1910.269 requires the employer to establish minimum approach distances no less than the distances computed by Table R-3 for ac systems so that employees can work safely without risk of sparkover. 2
2 Sparkover is a disruptive electric discharge in which an electric arc forms and electric current passes through air.
Unless the employee is using electrical protective equipment, air is the insulating medium between the employee and energized parts. The distance between the employee and an energized part must be sufficient for the air to withstand the maximum transient overvoltage that can reach the worksite under the working conditions and practices the employee is using. This distance is the minimum air insulation distance, and it is equal to the electrical component of the minimum approach distance.
Normal system design may provide or include a means (such as lightning arrestors) to control maximum anticipated transient overvoltages, or the employer may use temporary devices (portable protective gaps) or measures (such as preventing automatic circuit breaker reclosing) to achieve the same result. Paragraph (l)(3)(ii) of § 1910.269 requires the employer to determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis or assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table R-9, which specifies the following maximums for ac systems:
72.6 to 420.0 kilovolts—3.5 per unit
420.1 to 550.0 kilovolts—3.0 per unit
550.1 to 800.0 kilovolts—2.5 per unit
See paragraph IV.A.2, later in this appendix, for additional discussion of maximum transient overvoltages.
D. Types of exposures. Employees working on or near energized electric power generation, transmission, and distribution systems face two kinds of exposures: Phase-to-ground and phase-to-phase. The exposure is phase-to-ground: (1) With respect to an energized part, when the employee is at ground potential or (2) with respect to ground, when an employee is at the potential of the energized part during live-line barehand work. The exposure is phase-to-phase, with respect to an energized part, when an employee is at the potential of another energized part (at a different potential) during live-line barehand work.
III. Determination of Minimum Approach Distances for AC Voltages Greater Than 300 Volts
A. Voltages of 301 to 5,000 volts. Test data generally forms the basis of minimum air insulation distances. The lowest voltage for which sufficient test data exists is 5,000 volts, and these data indicate that the minimum air insulation distance at that voltage is 20 millimeters (1 inch). Because the minimum air insulation distance increases with increasing voltage, and, conversely, decreases with decreasing voltage, an assumed minimum air insulation distance of 20 millimeters will protect against sparkover at voltages of 301 to 5,000 volts. Thus, 20 millimeters is the electrical component of the minimum approach distance for these voltages.
B. Voltages of 5.1 to 72.5 kilovolts. For voltages from 5.1 to 72.5 kilovolts, the Occupational Safety and Health Administration bases the methodology for calculating the electrical component of the minimum approach distance on Institute of Electrical and Electronic Engineers (IEEE) Standard 4-1995, Standard Techniques for High-Voltage Testing. Table 1 lists the critical sparkover distances from that standard as listed in IEEE Std 516-2009, IEEE Guide for Maintenance Methods on Energized Power Lines.
| 60 Hz Rod-to-Rod sparkover (kV peak) | Gap spacing from IEEE Std 4-1995 (cm) |
|---|---|
| 25 | 2 |
| 36 | 3 |
| 46 | 4 |
| 53 | 5 |
| 60 | 6 |
| 70 | 8 |
| 79 | 10 |
| 86 | 12 |
| 95 | 14 |
| 104 | 16 |
| 112 | 18 |
| 120 | 20 |
| 143 | 25 |
| 167 | 30 |
| 192 | 35 |
| 218 | 40 |
| 243 | 45 |
| 270 | 50 |
| 322 | 60 |
| Source: IEEE Std 516-2009. |
To use this table to determine the electrical component of the minimum approach distance, the employer must determine the peak phase-to-ground transient overvoltage and select a gap from the table that corresponds to that voltage as a withstand voltage rather than a critical sparkover voltage. To calculate the electrical component of the minimum approach distance for voltages between 5 and 72.5 kilovolts, use the following procedure:
1. Divide the phase-to-phase voltage by the square root of 3 to convert it to a phase-to-ground voltage.
2. Multiply the phase-to-ground voltage by the square root of 2 to convert the rms value of the voltage to the peak phase-to-ground voltage.
3. Multiply the peak phase-to-ground voltage by the maximum per-unit transient overvoltage, which, for this voltage range, is 3.0, as discussed later in this appendix. This is the maximum phase-to-ground transient overvoltage, which corresponds to the withstand voltage for the relevant exposure. 3
3 The withstand voltage is the voltage at which sparkover is not likely to occur across a specified distance. It is the voltage taken at the 3σ point below the sparkover voltage, assuming that the sparkover curve follows a normal distribution.
4. Divide the maximum phase-to-ground transient overvoltage by 0.85 to determine the corresponding critical sparkover voltage. (The critical sparkover voltage is 3 standard deviations (or 15 percent) greater than the withstand voltage.)
5. Determine the electrical component of the minimum approach distance from Table 1 through interpolation.
| Step | Maximum system phase-to-phase voltage (kV) | |||
|---|---|---|---|---|
| 15 | 36 | 46 | 72.5 | |
| 1. Divide by √3 | 8.7 | 20.8 | 26.6 | 41.9 |
| 2. Multiply by √2 | 12.2 | 29.4 | 37.6 | 59.2 |
| 3. Multiply by 3.0 | 36.7 | 88.2 | 112.7 | 177.6 |
| 4. Divide by 0.85 | 43.2 | 103.7 | 132.6 | 208.9 |
| 5. Interpolate from Table 1 | 3 + (7.2/10)*1 | 14 + (8.7/9)*2 | 20 + (12.6/23)*5 | 35 + (16.9/26)*5 |
| Electrical component of MAD (cm) | 3.72 | 15.93 | 22.74 | 38.25 |
C. Voltages of 72.6 to 800 kilovolts. For voltages of 72.6 kilovolts to 800 kilovolts, this section bases the electrical component of minimum approach distances, before the application of any altitude correction factor, on the following formula:
Equation 1—For Voltages of 72.6 kV to 800 kV
D
C
a
V
L
G
T
Where:
D
C
a
4
4 Test data demonstrates that the saturation factor is greater than 0 at peak voltages of about 630 kilovolts. Systems operating at 345 kilovolts (or maximum system voltages of 362 kilovolts) can have peak maximum transient overvoltages exceeding 630 kilovolts. Table R-3 sets equations for calculating a based on peak voltage.
V
L-G
T
In Equation 1, C is 0.01: (1) For phase-to-ground exposures that the employer can demonstrate consist only of air across the approach distance (gap) and (2) for phase-to-phase exposures if the employer can demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap. Otherwise, C is 0.011.
In Equation 1, the term a varies depending on whether the employee's exposure is phase-to-ground or phase-to-phase and on whether objects are in the gap. The employer must use the equations in Table 3 to calculate a. Sparkover test data with insulation spanning the gap form the basis for the equations for phase-to-ground exposures, and sparkover test data with only air in the gap form the basis for the equations for phase-to-phase exposures. The phase-to-ground equations result in slightly higher values of a, and, consequently, produce larger minimum approach distances, than the phase-to-phase equations for the same value of V Peak.
| Phase-to-ground exposures | |||
|---|---|---|---|
| V Peak = T L-G V L-G √2 | 635 kV or less | 635.1 to 915 kV | 915.1 to 1,050 kV |
| a | 0 | ( V Peak - 635)/140,000 | ( V Peak -645)/135,000 |
| V Peak = T L-G V L-G √2 | More than 1,050 kV | ||
| a | ( V Peak -675)/125,000 | ||
| Phase-to-phase exposures 1 | |||
| V Peak = (1.35 T L-G + 0.45) V L-G √2 | 630 kV or less | 630.1 to 848 kV | 848.1 to 1,131 kV |
| a | 0 | ( V Peak -630)/155,000 | ( V Peak -633.6)/152,207 |
| V Peak = (1.35 T L-G + 0.45) V L-G √2 | 1,131.1 to 1,485 kV | More than 1,485 kV |
|---|---|---|
| a | ( V Peak -628)/153,846 | ( V Peak -350.5)/203,666 |
| 1 Use the equations for phase-to-ground exposures (with V Peak for phase-to-phase exposures) unless the employer can demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap. |
In Equation 1, T is the maximum transient overvoltage factor in per unit. As noted earlier, § 1910.269(l)(3)(ii) requires the employer to determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis or assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table R-9. For phase-to-ground exposures, the employer uses this value, called T L-G, as T in Equation 1. IEEE Std 516-2009 provides the following formula to calculate the phase-to-phase maximum transient overvoltage, T L-L, from T L-G :
T
L-L
T
L-G
For phase-to-phase exposures, the employer uses this value as T in Equation 1.
D. Provisions for inadvertent movement. The minimum approach distance must include an “adder” to compensate for the inadvertent movement of the worker relative to an energized part or the movement of the part relative to the worker. This “adder” must account for this possible inadvertent movement and provide the worker with a comfortable and safe zone in which to work. Employers must add the distance for inadvertent movement (called the “ergonomic component of the minimum approach distance”) to the electrical component to determine the total safe minimum approach distances used in live-line work.
The Occupational Safety and Health Administration based the ergonomic component of the minimum approach distance on response time-distance analysis. This technique uses an estimate of the total response time to a hazardous incident and converts that time to the distance traveled. For example, the driver of a car takes a given amount of time to respond to a “stimulus” and stop the vehicle. The elapsed time involved results in the car's traveling some distance before coming to a complete stop. This distance depends on the speed of the car at the time the stimulus appears and the reaction time of the driver.
In the case of live-line work, the employee must first perceive that he or she is approaching the danger zone. Then, the worker responds to the danger and must decelerate and stop all motion toward the energized part. During the time it takes to stop, the employee will travel some distance. This is the distance the employer must add to the electrical component of the minimum approach distance to obtain the total safe minimum approach distance.
At voltages from 751 volts to 72.5 kilovolts, 5 the electrical component of the minimum approach distance is smaller than the ergonomic component. At 72.5 kilovolts, the electrical component is only a little more than 0.3 meters (1 foot). An ergonomic component of the minimum approach distance must provide for all the worker's unanticipated movements. At these voltages, workers generally use rubber insulating gloves; however, these gloves protect only a worker's hands and arms. Therefore, the energized object must be at a safe approach distance to protect the worker's face. In this case, 0.61 meters (2 feet) is a sufficient and practical ergonomic component of the minimum approach distance.
5 For voltages of 50 to 300 volts, Table R-3 specifies a minimum approach distance of “avoid contact.” The minimum approach distance for this voltage range contains neither an electrical component nor an ergonomic component.
For voltages between 72.6 and 800 kilovolts, employees must use different work practices during energized line work. Generally, employees use live-line tools (hot sticks) to perform work on energized equipment. These tools, by design, keep the energized part at a constant distance from the employee and, thus, maintain the appropriate minimum approach distance automatically.
The location of the worker and the type of work methods the worker is using also influence the length of the ergonomic component of the minimum approach distance. In this higher voltage range, the employees use work methods that more tightly control their movements than when the workers perform work using rubber insulating gloves. The worker, therefore, is farther from the energized line or equipment and must be more precise in his or her movements just to perform the work. For these reasons, this section adopts an ergonomic component of the minimum approach distance of 0.31 m (1 foot) for voltages between 72.6 and 800 kilovolts.
| Voltage range (kV) | Distance | |
|---|---|---|
| m | ft | |
| 0.301 to 0.750 | 0.31 | 1.0 |
| 0.751 to 72.5 | 0.61 | 2.0 |
| 72.6 to 800 | 0.31 | 1.0 |
| Note: The employer must add this distance to the electrical component of the minimum approach distance to obtain the full minimum approach distance. |
The ergonomic component of the minimum approach distance accounts for errors in maintaining the minimum approach distance (which might occur, for example, if an employee misjudges the length of a conductive object he or she is holding), and for errors in judging the minimum approach distance. The ergonomic component also accounts for inadvertent movements by the employee, such as slipping. In contrast, the working position selected to properly maintain the minimum approach distance must account for all of an employee's reasonably likely movements and still permit the employee to adhere to the applicable minimum approach distance. (See Figure 1.) Reasonably likely movements include an employee's adjustments to tools, equipment, and working positions and all movements needed to perform the work. For example, the employee should be able to perform all of the following actions without straying into the minimum approach distance:
• Adjust his or her hardhat,
• maneuver a tool onto an energized part with a reasonable amount of overreaching or underreaching,
• reach for and handle tools, material, and equipment passed to him or her, and
• adjust tools, and replace components on them, when necessary during the work procedure.
The training of qualified employees required under § 1910.269(a)(2), and the job planning and briefing required under § 1910.269(c), must address selection of a proper working position.
E. Miscellaneous correction factors. Changes in the air medium that forms the insulation influences the strength of an air gap. A brief discussion of each factor follows.
1. Dielectric strength of air. The dielectric strength of air in a uniform electric field at standard atmospheric conditions is approximately 3 kilovolts per millimeter. 6 The pressure, temperature, and humidity of the air, the shape, dimensions, and separation of the electrodes, and the characteristics of the applied voltage (wave shape) affect the disruptive gradient.
6 For the purposes of estimating arc length, § 1910.269 generally assumes a more conservative dielectric strength of 10 kilovolts per 25.4 millimeters, consistent with assumptions made in consensus standards such as the National Electrical Safety Code (IEEE C2-2012). The more conservative value accounts for variables such as electrode shape, wave shape, and a certain amount of overvoltage.
2. Atmospheric effect. The empirically determined electrical strength of a given gap is normally applicable at standard atmospheric conditions (20 °C, 101.3 kilopascals, 11 grams/cubic centimeter humidity). An increase in the density (humidity) of the air inhibits sparkover for a given air gap. The combination of temperature and air pressure that results in the lowest gap sparkover voltage is high temperature and low pressure. This combination of conditions is not likely to occur. Low air pressure, generally associated with high humidity, causes increased electrical strength. An average air pressure generally correlates with low humidity. Hot and dry working conditions normally result in reduced electrical strength. The equations for minimum approach distances in Table R-3 assume standard atmospheric conditions.
3. Altitude. The reduced air pressure at high altitudes causes a reduction in the electrical strength of an air gap. An employer must increase the minimum approach distance by about 3 percent per 300 meters (1,000 feet) of increased altitude for altitudes above 900 meters (3,000 feet). Table R-5 specifies the altitude correction factor that the employer must use in calculating minimum approach distances.
IV. Determining Minimum Approach Distances
A. Factors Affecting Voltage Stress at the Worksite
1. System voltage (nominal). The nominal system voltage range determines the voltage for purposes of calculating minimum approach distances. The employer selects the range in which the nominal system voltage falls, as given in the relevant table, and uses the highest value within that range in per-unit calculations.
2. Transient overvoltages. Operation of switches or circuit breakers, a fault on a line or circuit or on an adjacent circuit, and similar activities may generate transient overvoltages on an electrical system. Each overvoltage has an associated transient voltage wave shape. The wave shape arriving at the site and its magnitude vary considerably.
In developing requirements for minimum approach distances, the Occupational Safety and Health Administration considered the most common wave shapes and the magnitude of transient overvoltages found on electric power generation, transmission, and distribution systems. The equations in Table R-3 for minimum approach distances use per-unit maximum transient overvoltages, which are relative to the nominal maximum voltage of the system. For example, a maximum transient overvoltage value of 3.0 per unit indicates that the highest transient overvoltage is 3.0 times the nominal maximum system voltage.
3. Typical magnitude of overvoltages. Table 5 lists the magnitude of typical transient overvoltages.
| Cause | Magnitude (per unit) |
|---|---|
| Energized 200-mile line without closing resistors | 3.5 |
| Energized 200-mile line with one-step closing resistor | 2.1 |
| Energized 200-mile line with multistep resistor | 2.5 |
| Reclosing with trapped charge one-step resistor | 2.2 |
| Opening surge with single restrike | 3.0 |
| Fault initiation unfaulted phase | 2.1 |
| Fault initiation adjacent circuit | 2.5 |
| Fault clearing | 1.7 to 1.9 |
4. Standard deviation—air-gap withstand. For each air gap length under the same atmospheric conditions, there is a statistical variation in the breakdown voltage. The probability of breakdown against voltage has a normal (Gaussian) distribution. The standard deviation of this distribution varies with the wave shape, gap geometry, and atmospheric conditions. The withstand voltage of the air gap is three standard deviations (3σ) below the critical sparkover voltage. (The critical sparkover voltage is the crest value of the impulse wave that, under specified conditions, causes sparkover 50 percent of the time. An impulse wave of three standard deviations below this value, that is, the withstand voltage, has a probability of sparkover of approximately 1 in 1,000.)
5. Broken Insulators. Tests show reductions in the insulation strength of insulator strings with broken skirts. Broken units may lose up to 70 percent of their withstand capacity. Because an employer cannot determine the insulating capability of a broken unit without testing it, the employer must consider damaged units in an insulator to have no insulating value. Additionally, the presence of a live-line tool alongside an insulator string with broken units may further reduce the overall insulating strength. The number of good units that must be present in a string for it to be “insulated” as defined by § 1910.269(x) depends on the maximum overvoltage possible at the worksite.
B. Minimum Approach Distances Based on Known, Maximum-Anticipated Per-Unit Transient Overvoltages
1. Determining the minimum approach distance for AC systems. Under § 1910.269(l)(3)(ii), the employer must determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis or must assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table R-9. When the employer conducts an engineering analysis of the system and determines that the maximum transient overvoltage is lower than specified by Table R-9, the employer must ensure that any conditions assumed in the analysis, for example, that employees block reclosing on a circuit or install portable protective gaps, are present during energized work. To ensure that these conditions are present, the employer may need to institute new live-work procedures reflecting the conditions and limitations set by the engineering analysis.
2. Calculation of reduced approach distance values. An employer may take the following steps to reduce minimum approach distances when the maximum transient overvoltage on the system (that is, the maximum transient overvoltage without additional steps to control overvoltages) produces unacceptably large minimum approach distances:
Step 1. Determine the maximum voltage (with respect to a given nominal voltage range) for the energized part.
Step 2. Determine the technique to use to control the maximum transient overvoltage. (See paragraphs IV.C and IV.D of this appendix.) Determine the maximum transient overvoltage that can exist at the worksite with that form of control in place and with a confidence level of 3σ. This voltage is the withstand voltage for the purpose of calculating the appropriate minimum approach distance.
Step 3. Direct employees to implement procedures to ensure that the control technique is in effect during the course of the work.
Step 4. Using the new value of transient overvoltage in per unit, calculate the required minimum approach distance from Table R-3.
C. Methods of Controlling Possible Transient Overvoltage Stress Found on a System
1. Introduction. There are several means of controlling overvoltages that occur on transmission systems. For example, the employer can modify the operation of circuit breakers or other switching devices to reduce switching transient overvoltages. Alternatively, the employer can hold the overvoltage to an acceptable level by installing surge arresters or portable protective gaps on the system. In addition, the employer can change the transmission system to minimize the effect of switching operations. Section 4.8 of IEEE Std 516-2009 describes various ways of controlling, and thereby reducing, maximum transient overvoltages.
2. Operation of circuit breakers. 7 The maximum transient overvoltage that can reach the worksite is often the result of switching on the line on which employees are working. Disabling automatic reclosing during energized line work, so that the line will not be reenergized after being opened for any reason, limits the maximum switching surge overvoltage to the larger of the opening surge or the greatest possible fault-generated surge, provided that the devices (for example, insertion resistors) are operable and will function to limit the transient overvoltage and that circuit breaker restrikes do not occur. The employer must ensure the proper functioning of insertion resistors and other overvoltage-limiting devices when the employer's engineering analysis assumes their proper operation to limit the overvoltage level. If the employer cannot disable the reclosing feature (because of system operating conditions), other methods of controlling the switching surge level may be necessary.
7 The detailed design of a circuit interrupter, such as the design of the contacts, resistor insertion, and breaker timing control, are beyond the scope of this appendix. The design of the system generally accounts for these features. This appendix only discusses features that can limit the maximum switching transient overvoltage on a system.
Transient surges on an adjacent line, particularly for double circuit construction, may cause a significant overvoltage on the line on which employees are working. The employer's engineering analysis must account for coupling to adjacent lines.
3. Surge arresters. The use of modern surge arresters allows a reduction in the basic impulse-insulation levels of much transmission system equipment. The primary function of early arresters was to protect the system insulation from the effects of lightning. Modern arresters not only dissipate lightning-caused transients, but may also control many other system transients caused by switching or faults.
The employer may use properly designed arresters to control transient overvoltages along a transmission line and thereby reduce the requisite length of the insulator string and possibly the maximum transient overvoltage on the line. 8
8 Surge arrester application is beyond the scope of this appendix. However, if the employer installs the arrester near the work site, the application would be similar to the protective gaps discussed in paragraph IV.D of this appendix.
4. Switching Restrictions. Another form of overvoltage control involves establishing switching restrictions, whereby the employer prohibits the operation of circuit breakers until certain system conditions are present. The employer restricts switching by using a tagging system, similar to that used for a permit, except that the common term used for this activity is a “hold-off” or “restriction.” These terms indicate that the restriction does not prevent operation, but only modifies the operation during the live-work activity.
D. Minimum Approach Distance Based on Control of Maximum Transient Overvoltage at the Worksite
When the employer institutes control of maximum transient overvoltage at the worksite by installing portable protective gaps, the employer may calculate the minimum approach distance as follows:
Step 1. Select the appropriate withstand voltage for the protective gap based on system requirements and an acceptable probability of gap sparkover. 9
9 The employer should check the withstand voltage to ensure that it results in a probability of gap flashover that is acceptable from a system outage perspective. (In other words, a gap sparkover will produce a system outage. The employer should determine whether such an outage will impact overall system performance to an acceptable degree.) In general, the withstand voltage should be at least 1.25 times the maximum crest operating voltage.
Step 2. Determine a gap distance that provides a withstand voltage 10 greater than or equal to the one selected in the first step. 11
10 The manufacturer of the gap provides, based on test data, the critical sparkover voltage for each gap spacing (for example, a critical sparkover voltage of 665 kilovolts for a gap spacing of 1.2 meters). The withstand voltage for the gap is equal to 85 percent of its critical sparkover voltage.
11 Switch steps 1 and 2 if the length of the protective gap is known.
Step 3. Use 110 percent of the gap's critical sparkover voltage to determine the phase-to-ground peak voltage at gap sparkover ( V PPG Peak ).
Step 4. Determine the maximum transient overvoltage, phase-to-ground, at the worksite from the following formula:
Step 5. Use this value of T 12 in the equation in Table R-3 to obtain the minimum approach distance. If the worksite is no more than 900 meters (3,000 feet) above sea level, the employer may use this value of T to determine the minimum approach distance from Table 14 through Table 21.
12 IEEE Std 516-2009 states that most employers add 0.2 to the calculated value of T as an additional safety factor.
Sample protective gap calculations.
Problem: Employees are to perform work on a 500-kilovolt transmission line at sea level that is subject to transient overvoltages of 2.4 p.u. The maximum operating voltage of the line is 550 kilovolts. Determine the length of the protective gap that will provide the minimum practical safe approach distance. Also, determine what that minimum approach distance is.
Step 1. Calculate the smallest practical maximum transient overvoltage (1.25 times the crest phase-to-ground voltage): 13
13 To eliminate sparkovers due to minor system disturbances, the employer should use a withstand voltage no lower than 1.25 p.u. Note that this is a practical, or operational, consideration only. It may be feasible for the employer to use lower values of withstand voltage.
Step 2. Using test data for a particular protective gap, select a gap that has a critical sparkover voltage greater than or equal to:
kV
kV
For example, if a protective gap with a 1.22-m (4.0-foot) spacing tested to a critical sparkover voltage of 665 kilovolts (crest), select this gap spacing.
Step 3. The phase-to-ground peak voltage at gap sparkover ( V PPG Peak ) is 110 percent of the value from the previous step:
kV
kV
This value corresponds to the withstand voltage of the electrical component of the minimum approach distance.
Step 4. Use this voltage to determine the worksite value of T:
Step 5. Use this value of T in the equation in Table R-3 to obtain the minimum approach distance, or look up the minimum approach distance in Table 14 through Table 21:
MAD
E. Location of Protective Gaps
1. Adjacent structures. The employer may install the protective gap on a structure adjacent to the worksite, as this practice does not significantly reduce the protection afforded by the gap.
2. Terminal stations. Gaps installed at terminal stations of lines or circuits provide a level of protection; however, that level of protection may not extend throughout the length of the line to the worksite. The use of substation terminal gaps raises the possibility that separate surges could enter the line at opposite ends, each with low enough magnitude to pass the terminal gaps without sparkover. When voltage surges occur simultaneously at each end of a line and travel toward each other, the total voltage on the line at the point where they meet is the arithmetic sum of the two surges. A gap installed within 0.8 km (0.5 mile) of the worksite will protect against such intersecting waves. Engineering studies of a particular line or system may indicate that employers can adequately protect employees by installing gaps at even more distant locations. In any event, unless using the default values for T from Table R-9, the employer must determine T at the worksite.
3. Worksite. If the employer installs protective gaps at the worksite, the gap setting establishes the worksite impulse insulation strength. Lightning strikes as far as 6 miles from the worksite can cause a voltage surge greater than the gap withstand voltage, and a gap sparkover can occur. In addition, the gap can sparkover from overvoltages on the line that exceed the withstand voltage of the gap. Consequently, the employer must protect employees from hazards resulting from any sparkover that could occur.
F. Disabling automatic reclosing. There are two reasons to disable the automatic-reclosing feature of circuit-interrupting devices while employees are performing live-line work:
• To prevent reenergization of a circuit faulted during the work, which could create a hazard or result in more serious injuries or damage than the injuries or damage produced by the original fault;
• To prevent any transient overvoltage caused by the switching surge that would result if the circuit were reenergized.
However, due to system stability considerations, it may not always be feasible to disable the automatic-reclosing feature.
V. Minimum Approach-Distance Tables
A. Legacy tables. Employers may use the minimum approach distances in Table 6 through Table 13 until March 31, 2015.
| Voltage range phase to phase (kV) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 0.05 to 1.0 | Avoid Contact | Avoid Contact | ||
| 1.1 to 15.0 | 0.64 | 2.10 | 0.66 | 2.20 |
| 15.1 to 36.0 | 0.72 | 2.30 | 0.77 | 2.60 |
| 36.1 to 46.0 | 0.77 | 2.60 | 0.85 | 2.80 |
| 46.1 to 72.5 | 0.90 | 3.00 | 1.05 | 3.50 |
| 72.6 to 121 | 0.95 | 3.20 | 1.29 | 4.30 |
| 138 to 145 | 1.09 | 3.60 | 1.50 | 4.90 |
| 161 to 169 | 1.22 | 4.00 | 1.71 | 5.70 |
| 230 to 242 | 1.59 | 5.30 | 2.27 | 7.50 |
| 345 to 362 | 2.59 | 8.50 | 3.80 | 12.50 |
| 500 to 550 | 3.42 | 11.30 | 5.50 | 18.10 |
| 765 to 800 | 4.53 | 14.90 | 7.91 | 26.00 |
| Note: The clear live-line tool distance must equal or exceed the values for the indicated voltage ranges. |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 2.0 | 0.74 | 2.42 | 1.09 | 3.58 |
| 2.1 | 0.76 | 2.50 | 1.09 | 3.58 |
| 2.2 | 0.79 | 2.58 | 1.12 | 3.67 |
| 2.3 | 0.81 | 2.67 | 1.14 | 3.75 |
| 2.4 | 0.84 | 2.75 | 1.17 | 3.83 |
| 2.5 | 0.84 | 2.75 | 1.19 | 3.92 |
| 2.6 | 0.86 | 2.83 | 1.22 | 4.00 |
| 2.7 | 0.89 | 2.92 | 1.24 | 4.08 |
| 2.8 | 0.91 | 3.00 | 1.24 | 4.08 |
| 2.9 | 0.94 | 3.08 | 1.27 | 4.17 |
| 3.0 | 0.97 | 3.17 | 1.30 | 4.25 |
| Note 1: The employer may apply the distance specified in this table only where the employer determines the maximum anticipated per-unit transient overvoltage by engineering analysis. (Table 6 applies otherwise.) | ||||
| Note 2: The distances specified in this table are the air, bare-hand, and live-line tool distances. |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 2.0 | 0.84 | 2.75 | 1.24 | 4.08 |
| 2.1 | 0.86 | 2.83 | 1.27 | 4.17 |
| 2.2 | 0.89 | 2.92 | 1.30 | 4.25 |
| 2.3 | 0.91 | 3.00 | 1.32 | 4.33 |
| 2.4 | 0.94 | 3.08 | 1.35 | 4.42 |
| 2.5 | 0.97 | 3.17 | 1.37 | 4.50 |
| 2.6 | 0.99 | 3.25 | 1.40 | 4.58 |
| 2.7 | 1.02 | 3.33 | 1.42 | 4.67 |
| 2.8 | 1.04 | 3.42 | 1.45 | 4.75 |
| 2.9 | 1.07 | 3.50 | 1.47 | 4.83 |
| 3.0 | 1.09 | 3.58 | 1.50 | 4.92 |
| Note 1: The employer may apply the distance specified in this table only where the employer determines the maximum anticipated per-unit transient overvoltage by engineering analysis. (Table 6 applies otherwise.) | ||||
| Note 2: The distances specified in this table are the air, bare-hand, and live-line tool distances. |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 2.0 | 0.91 | 3.00 | 1.42 | 4.67 |
| 2.1 | 0.97 | 3.17 | 1.45 | 4.75 |
| 2.2 | 0.99 | 3.25 | 1.47 | 4.83 |
| 2.3 | 1.02 | 3.33 | 1.50 | 4.92 |
| 2.4 | 1.04 | 3.42 | 1.52 | 5.00 |
| 2.5 | 1.07 | 3.50 | 1.57 | 5.17 |
| 2.6 | 1.12 | 3.67 | 1.60 | 5.25 |
| 2.7 | 1.14 | 3.75 | 1.63 | 5.33 |
| 2.8 | 1.17 | 3.83 | 1.65 | 5.42 |
| 2.9 | 1.19 | 3.92 | 1.68 | 5.50 |
| 3.0 | 1.22 | 4.00 | 1.73 | 5.67 |
| Note 1: The employer may apply the distance specified in this table only where the employer determines the maximum anticipated per-unit transient overvoltage by engineering analysis. (Table 6 applies otherwise.) | ||||
| Note 2: The distances specified in this table are the air, bare-hand, and live-line tool distances. |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 2.0 | 1.17 | 3.83 | 1.85 | 6.08 |
| 2.1 | 1.22 | 4.00 | 1.91 | 6.25 |
| 2.2 | 1.24 | 4.08 | 1.93 | 6.33 |
| 2.3 | 1.30 | 4.25 | 1.98 | 6.50 |
| 2.4 | 1.35 | 4.42 | 2.01 | 6.58 |
| 2.5 | 1.37 | 4.50 | 2.06 | 6.75 |
| 2.6 | 1.42 | 4.67 | 2.11 | 6.92 |
| 2.7 | 1.47 | 4.83 | 2.13 | 7.00 |
| 2.8 | 1.50 | 4.92 | 2.18 | 7.17 |
| 2.9 | 1.55 | 5.08 | 2.24 | 7.33 |
| 3.0 | 1.60 | 5.25 | 2.29 | 7.50 |
| Note 1: The employer may apply the distance specified in this table only where the employer determines the maximum anticipated per-unit transient overvoltage by engineering analysis. (Table 6 applies otherwise.) | ||||
| Note 2: The distances specified in this table are the air, bare-hand, and live-line tool distances. |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 2.0 | 1.60 | 5.25 | 2.62 | 8.58 |
| 2.1 | 1.65 | 5.42 | 2.69 | 8.83 |
| 2.2 | 1.75 | 5.75 | 2.79 | 9.17 |
| 2.3 | 1.85 | 6.08 | 2.90 | 9.50 |
| 2.4 | 1.93 | 6.33 | 3.02 | 9.92 |
| 2.5 | 2.03 | 6.67 | 3.15 | 10.33 |
| 2.6 | 2.16 | 7.08 | 3.28 | 10.75 |
| 2.7 | 2.26 | 7.42 | 3.40 | 11.17 |
| 2.8 | 2.36 | 7.75 | 3.53 | 11.58 |
| 2.9 | 2.49 | 8.17 | 3.68 | 12.08 |
| 3.0 | 2.59 | 8.50 | 3.81 | 12.50 |
| Note 1: The employer may apply the distance specified in this table only where the employer determines the maximum anticipated per-unit transient overvoltage by engineering analysis. (Table 6 applies otherwise.) | ||||
| Note 2: The distances specified in this table are the air, bare-hand, and live-line tool distances. |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.83 | 6.00 | 2.24 | 7.33 |
| 1.6 | 1.98 | 6.50 | 2.67 | 8.75 |
| 1.7 | 2.13 | 7.00 | 3.10 | 10.17 |
| 1.8 | 2.31 | 7.58 | 3.53 | 11.58 |
| 1.9 | 2.46 | 8.08 | 4.01 | 13.17 |
| 2.0 | 2.67 | 8.75 | 4.52 | 14.83 |
| 2.1 | 2.84 | 9.33 | 4.75 | 15.58 |
| 2.2 | 3.02 | 9.92 | 4.98 | 16.33 |
| 2.3 | 3.20 | 10.50 | 5.23 | 17.17 |
| 2.4 | 3.43 | 11.25 | 5.51 | 18.08 |
| Note 1: The employer may apply the distance specified in this table only where the employer determines the maximum anticipated per-unit transient overvoltage by engineering analysis. (Table 6 applies otherwise.) | ||||
| Note 2: The distances specified in this table are the air, bare-hand, and live-line tool distances. |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 2.95 | 9.67 | 3.68 | 12.08 |
| 1.6 | 3.25 | 10.67 | 4.42 | 14.50 |
| 1.7 | 3.56 | 11.67 | 5.23 | 17.17 |
| 1.8 | 3.86 | 12.67 | 6.07 | 19.92 |
| 1.9 | 4.19 | 13.75 | 6.99 | 22.92 |
| 2.0 | 4.55 | 14.92 | 7.92 | 26.00 |
| Note 1: The employer may apply the distance specified in this table only where the employer determines the maximum anticipated per-unit transient overvoltage by engineering analysis. (Table 6 applies otherwise.) | ||||
| Note 2: The distances specified in this table are the air, bare-hand, and live-line tool distances. |
B. Alternative minimum approach distances. Employers may use the minimum approach distances in Table 14 through Table 21 provided that the employer follows the notes to those tables.
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 0.67 | 2.2 | 0.84 | 2.8 |
| 1.6 | 0.69 | 2.3 | 0.87 | 2.9 |
| 1.7 | 0.71 | 2.3 | 0.90 | 3.0 |
| 1.8 | 0.74 | 2.4 | 0.93 | 3.1 |
| 1.9 | 0.76 | 2.5 | 0.96 | 3.1 |
| 2.0 | 0.78 | 2.6 | 0.99 | 3.2 |
| 2.1 | 0.81 | 2.7 | 1.01 | 3.3 |
| 2.2 | 0.83 | 2.7 | 1.04 | 3.4 |
| 2.3 | 0.85 | 2.8 | 1.07 | 3.5 |
| 2.4 | 0.88 | 2.9 | 1.10 | 3.6 |
| 2.5 | 0.90 | 3.0 | 1.13 | 3.7 |
| 2.6 | 0.92 | 3.0 | 1.16 | 3.8 |
| 2.7 | 0.95 | 3.1 | 1.19 | 3.9 |
| 2.8 | 0.97 | 3.2 | 1.22 | 4.0 |
| 2.9 | 0.99 | 3.2 | 1.24 | 4.1 |
| 3.0 | 1.02 | 3.3 | 1.27 | 4.2 |
| 3.1 | 1.04 | 3.4 | 1.30 | 4.3 |
| 3.2 | 1.06 | 3.5 | 1.33 | 4.4 |
| 3.3 | 1.09 | 3.6 | 1.36 | 4.5 |
| 3.4 | 1.11 | 3.6 | 1.39 | 4.6 |
| 3.5 | 1.13 | 3.7 | 1.42 | 4.7 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 0.74 | 2.4 | 0.95 | 3.1 |
| 1.6 | 0.76 | 2.5 | 0.98 | 3.2 |
| 1.7 | 0.79 | 2.6 | 1.02 | 3.3 |
| 1.8 | 0.82 | 2.7 | 1.05 | 3.4 |
| 1.9 | 0.85 | 2.8 | 1.08 | 3.5 |
| 2.0 | 0.88 | 2.9 | 1.12 | 3.7 |
| 2.1 | 0.90 | 3.0 | 1.15 | 3.8 |
| 2.2 | 0.93 | 3.1 | 1.19 | 3.9 |
| 2.3 | 0.96 | 3.1 | 1.22 | 4.0 |
| 2.4 | 0.99 | 3.2 | 1.26 | 4.1 |
| 2.5 | 1.02 | 3.3 | 1.29 | 4.2 |
| 2.6 | 1.04 | 3.4 | 1.33 | 4.4 |
| 2.7 | 1.07 | 3.5 | 1.36 | 4.5 |
| 2.8 | 1.10 | 3.6 | 1.39 | 4.6 |
| 2.9 | 1.13 | 3.7 | 1.43 | 4.7 |
| 3.0 | 1.16 | 3.8 | 1.46 | 4.8 |
| 3.1 | 1.19 | 3.9 | 1.50 | 4.9 |
| 3.2 | 1.21 | 4.0 | 1.53 | 5.0 |
| 3.3 | 1.24 | 4.1 | 1.57 | 5.2 |
| 3.4 | 1.27 | 4.2 | 1.60 | 5.2 |
| 3.5 | 1.30 | 4.3 | 1.64 | 5.4 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 0.81 | 2.7 | 1.05 | 3.4 |
| 1.6 | 0.84 | 2.8 | 1.09 | 3.6 |
| 1.7 | 0.87 | 2.9 | 1.13 | 3.7 |
| 1.8 | 0.90 | 3.0 | 1.17 | 3.8 |
| 1.9 | 0.94 | 3.1 | 1.21 | 4.0 |
| 2.0 | 0.97 | 3.2 | 1.25 | 4.1 |
| 2.1 | 1.00 | 3.3 | 1.29 | 4.2 |
| 2.2 | 1.03 | 3.4 | 1.33 | 4.4 |
| 2.3 | 1.07 | 3.5 | 1.37 | 4.5 |
| 2.4 | 1.10 | 3.6 | 1.41 | 4.6 |
| 2.5 | 1.13 | 3.7 | 1.45 | 4.8 |
| 2.6 | 1.17 | 3.8 | 1.49 | 4.9 |
| 2.7 | 1.20 | 3.9 | 1.53 | 5.0 |
| 2.8 | 1.23 | 4.0 | 1.57 | 5.2 |
| 2.9 | 1.26 | 4.1 | 1.61 | 5.3 |
| 3.0 | 1.30 | 4.3 | 1.65 | 5.4 |
| 3.1 | 1.33 | 4.4 | 1.70 | 5.6 |
| 3.2 | 1.36 | 4.5 | 1.76 | 5.8 |
| 3.3 | 1.39 | 4.6 | 1.82 | 6.0 |
| 3.4 | 1.43 | 4.7 | 1.88 | 6.2 |
| 3.5 | 1.46 | 4.8 | 1.94 | 6.4 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.02 | 3.3 | 1.37 | 4.5 |
| 1.6 | 1.06 | 3.5 | 1.43 | 4.7 |
| 1.7 | 1.11 | 3.6 | 1.48 | 4.9 |
| 1.8 | 1.16 | 3.8 | 1.54 | 5.1 |
| 1.9 | 1.21 | 4.0 | 1.60 | 5.2 |
| 2.0 | 1.25 | 4.1 | 1.66 | 5.4 |
| 2.1 | 1.30 | 4.3 | 1.73 | 5.7 |
| 2.2 | 1.35 | 4.4 | 1.81 | 5.9 |
| 2.3 | 1.39 | 4.6 | 1.90 | 6.2 |
| 2.4 | 1.44 | 4.7 | 1.99 | 6.5 |
| 2.5 | 1.49 | 4.9 | 2.08 | 6.8 |
| 2.6 | 1.53 | 5.0 | 2.17 | 7.1 |
| 2.7 | 1.58 | 5.2 | 2.26 | 7.4 |
| 2.8 | 1.63 | 5.3 | 2.36 | 7.7 |
| 2.9 | 1.67 | 5.5 | 2.45 | 8.0 |
| 3.0 | 1.72 | 5.6 | 2.55 | 8.4 |
| 3.1 | 1.77 | 5.8 | 2.65 | 8.7 |
| 3.2 | 1.81 | 5.9 | 2.76 | 9.1 |
| 3.3 | 1.88 | 6.2 | 2.86 | 9.4 |
| 3.4 | 1.95 | 6.4 | 2.97 | 9.7 |
| 3.5 | 2.01 | 6.6 | 3.08 | 10.1 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.37 | 4.5 | 1.99 | 6.5 |
| 1.6 | 1.44 | 4.7 | 2.13 | 7.0 |
| 1.7 | 1.51 | 5.0 | 2.27 | 7.4 |
| 1.8 | 1.58 | 5.2 | 2.41 | 7.9 |
| 1.9 | 1.65 | 5.4 | 2.56 | 8.4 |
| 2.0 | 1.72 | 5.6 | 2.71 | 8.9 |
| 2.1 | 1.79 | 5.9 | 2.87 | 9.4 |
| 2.2 | 1.87 | 6.1 | 3.03 | 9.9 |
| 2.3 | 1.97 | 6.5 | 3.20 | 10.5 |
| 2.4 | 2.08 | 6.8 | 3.37 | 11.1 |
| 2.5 | 2.19 | 7.2 | 3.55 | 11.6 |
| 2.6 | 2.29 | 7.5 | 3.73 | 12.2 |
| 2.7 | 2.41 | 7.9 | 3.91 | 12.8 |
| 2.8 | 2.52 | 8.3 | 4.10 | 13.5 |
| 2.9 | 2.64 | 8.7 | 4.29 | 14.1 |
| 3.0 | 2.76 | 9.1 | 4.49 | 14.7 |
| 3.1 | 2.88 | 9.4 | 4.69 | 15.4 |
| 3.2 | 3.01 | 9.9 | 4.90 | 16.1 |
| 3.3 | 3.14 | 10.3 | 5.11 | 16.8 |
| 3.4 | 3.27 | 10.7 | 5.32 | 17.5 |
| 3.5 | 3.41 | 11.2 | 5.52 | 18.1 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.53 | 5.0 | 2.40 | 7.9 |
| 1.6 | 1.62 | 5.3 | 2.58 | 8.5 |
| 1.7 | 1.70 | 5.6 | 2.75 | 9.0 |
| 1.8 | 1.78 | 5.8 | 2.94 | 9.6 |
| 1.9 | 1.88 | 6.2 | 3.13 | 10.3 |
| 2.0 | 1.99 | 6.5 | 3.33 | 10.9 |
| 2.1 | 2.12 | 7.0 | 3.53 | 11.6 |
| 2.2 | 2.24 | 7.3 | 3.74 | 12.3 |
| 2.3 | 2.37 | 7.8 | 3.95 | 13.0 |
| 2.4 | 2.50 | 8.2 | 4.17 | 13.7 |
| 2.5 | 2.64 | 8.7 | 4.40 | 14.4 |
| 2.6 | 2.78 | 9.1 | 4.63 | 15.2 |
| 2.7 | 2.93 | 9.6 | 4.87 | 16.0 |
| 2.8 | 3.07 | 10.1 | 5.11 | 16.8 |
| 2.9 | 3.23 | 10.6 | 5.36 | 17.6 |
| 3.0 | 3.38 | 11.1 | 5.59 | 18.3 |
| 3.1 | 3.55 | 11.6 | 5.82 | 19.1 |
| 3.2 | 3.72 | 12.2 | 6.07 | 19.9 |
| 3.3 | 3.89 | 12.8 | 6.31 | 20.7 |
| 3.4 | 4.07 | 13.4 | 6.56 | 21.5 |
| 3.5 | 4.25 | 13.9 | 6.81 | 22.3 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.95 | 6.4 | 3.46 | 11.4 |
| 1.6 | 2.11 | 6.9 | 3.73 | 12.2 |
| 1.7 | 2.28 | 7.5 | 4.02 | 13.2 |
| 1.8 | 2.45 | 8.0 | 4.31 | 14.1 |
| 1.9 | 2.62 | 8.6 | 4.61 | 15.1 |
| 2.0 | 2.81 | 9.2 | 4.92 | 16.1 |
| 2.1 | 3.00 | 9.8 | 5.25 | 17.2 |
| 2.2 | 3.20 | 10.5 | 5.55 | 18.2 |
| 2.3 | 3.40 | 11.2 | 5.86 | 19.2 |
| 2.4 | 3.62 | 11.9 | 6.18 | 20.3 |
| 2.5 | 3.84 | 12.6 | 6.50 | 21.3 |
| 2.6 | 4.07 | 13.4 | 6.83 | 22.4 |
| 2.7 | 4.31 | 14.1 | 7.18 | 23.6 |
| 2.8 | 4.56 | 15.0 | 7.52 | 24.7 |
| 2.9 | 4.81 | 15.8 | 7.88 | 25.9 |
| 3.0 | 5.07 | 16.6 | 8.24 | 27.0 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 3.16 | 10.4 | 5.97 | 19.6 |
| 1.6 | 3.46 | 11.4 | 6.43 | 21.1 |
| 1.7 | 3.78 | 12.4 | 6.92 | 22.7 |
| 1.8 | 4.12 | 13.5 | 7.42 | 24.3 |
| 1.9 | 4.47 | 14.7 | 7.93 | 26.0 |
| 2.0 | 4.83 | 15.8 | 8.47 | 27.8 |
| 2.1 | 5.21 | 17.1 | 9.02 | 29.6 |
| 2.2 | 5.61 | 18.4 | 9.58 | 31.4 |
| 2.3 | 6.02 | 19.8 | 10.16 | 33.3 |
| 2.4 | 6.44 | 21.1 | 10.76 | 35.3 |
| 2.5 | 6.88 | 22.6 | 11.38 | 37.3 |
| Notes to Table 14 through Table 21: | ||||
| 1. The employer must determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis, as required by § 1910.269(l)(3)(ii), or assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table R-9. | ||||
| 2. For phase-to-phase exposures, the employer must demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap. | ||||
| 3. The worksite must be at an elevation of 900 meters (3,000 feet) or less above sea level. |
Appendix C to § 1910.269—Protection From Hazardous Differences in Electric Potential
I. Introduction
Current passing through an impedance impresses voltage across that impedance. Even conductors have some, albeit low, value of impedance. Therefore, if a “grounded” 1 object, such as a crane or deenergized and grounded power line, results in a ground fault on a power line, voltage is impressed on that grounded object. The voltage impressed on the grounded object depends largely on the voltage on the line, on the impedance of the faulted conductor, and on the impedance to “true,” or “absolute,” ground represented by the object. If the impedance of the object causing the fault is relatively large, the voltage impressed on the object is essentially the phase-to-ground system voltage. However, even faults to grounded power lines or to well grounded transmission towers or substation structures (which have relatively low values of impedance to ground) can result in hazardous voltages. 2 In all cases, the degree of the hazard depends on the magnitude of the current through the employee and the time of exposure. This appendix discusses methods of protecting workers against the possibility that grounded objects, such as cranes and other mechanical equipment, will contact energized power lines and that deenergized and grounded power lines will become accidentally energized.
1 This appendix generally uses the term “grounded” only with respect to grounding that the employer intentionally installs, for example, the grounding an employer installs on a deenergized conductor. However, in this case, the term “grounded” means connected to earth, regardless of whether or not that connection is intentional.
2 Thus, grounding systems for transmission towers and substation structures should be designed to minimize the step and touch potentials involved.
II. Voltage-Gradient Distribution
A. Voltage-gradient distribution curve. Absolute, or true, ground serves as a reference and always has a voltage of 0 volts above ground potential. Because there is an impedance between a grounding electrode and absolute ground, there will be a voltage difference between the grounding electrode and absolute ground under ground-fault conditions. Voltage dissipates from the grounding electrode (or from the grounding point) and creates a ground potential gradient. The voltage decreases rapidly with increasing distance from the grounding electrode. A voltage drop associated with this dissipation of voltage is a ground potential. Figure 1 is a typical voltage-gradient distribution curve (assuming a uniform soil texture).
B. Step and touch potentials. Figure 1 also shows that workers are at risk from step and touch potentials. Step potential is the voltage between the feet of a person standing near an energized grounded object (the electrode). In Figure 1, the step potential is equal to the difference in voltage between two points at different distances from the electrode (where the points represent the location of each foot in relation to the electrode). A person could be at risk of injury during a fault simply by standing near the object.
Touch potential is the voltage between the energized grounded object (again, the electrode) and the feet of a person in contact with the object. In Figure 1, the touch potential is equal to the difference in voltage between the electrode (which is at a distance of 0 meters) and a point some distance away from the electrode (where the point represents the location of the feet of the person in contact with the object). The touch potential could be nearly the full voltage across the grounded object if that object is grounded at a point remote from the place where the person is in contact with it. For example, a crane grounded to the system neutral and that contacts an energized line would expose any person in contact with the crane or its uninsulated load line to a touch potential nearly equal to the full fault voltage.
A. Definitions. The following definitions apply to section III of this appendix:
Bond. The electrical interconnection of conductive parts designed to maintain a common electric potential.
Bonding cable (bonding jumper). A cable connected to two conductive parts to bond the parts together.
Cluster bar. A terminal temporarily attached to a structure that provides a means for the attachment and bonding of grounding and bonding cables to the structure.
Ground. A conducting connection between an electric circuit or equipment and the earth, or to some conducting body that serves in place of the earth.
Grounding cable (grounding jumper). A cable connected between a deenergized part and ground. Note that grounding cables carry fault current and bonding cables generally do not. A cable that bonds two conductive parts but carries substantial fault current (for example, a jumper connected between one phase and a grounded phase) is a grounding cable.
Ground mat (grounding grid). A temporarily or permanently installed metallic mat or grating that establishes an equipotential surface and provides connection points for attaching grounds.
B. Analyzing the hazard. The employer can use an engineering analysis of the power system under fault conditions to determine whether hazardous step and touch voltages will develop. The analysis should determine the voltage on all conductive objects in the work area and the amount of time the voltage will be present. Based on the this analysis, the employer can select appropriate measures and protective equipment, including the measures and protective equipment outlined in Section III of this appendix, to protect each employee from hazardous differences in electric potential. For example, from the analysis, the employer will know the voltage remaining on conductive objects after employees install bonding and grounding equipment and will be able to select insulating equipment with an appropriate rating, as described in paragraph III.C.2 of this appendix.
C. Protecting workers on the ground. The employer may use several methods, including equipotential zones, insulating equipment, and restricted work areas, to protect employees on the ground from hazardous differences in electrical potential.
1. An equipotential zone will protect workers within it from hazardous step and touch potentials. (See Figure 3.) Equipotential zones will not, however, protect employees located either wholly or partially outside the protected area. The employer can establish an equipotential zone for workers on the ground, with respect to a grounded object, through the use of a metal mat connected to the grounded object. The employer can use a grounding grid to equalize the voltage within the grid or bond conductive objects in the immediate work area to minimize the potential between the objects and between each object and ground. (Bonding an object outside the work area can increase the touch potential to that object, however.) Section III.D of this appendix discusses equipotential zones for employees working on deenergized and grounded power lines.
2. Insulating equipment, such as rubber gloves, can protect employees handling grounded equipment and conductors from hazardous touch potentials. The insulating equipment must be rated for the highest voltage that can be impressed on the grounded objects under fault conditions (rather than for the full system voltage).
3. Restricting employees from areas where hazardous step or touch potentials could arise can protect employees not directly involved in performing the operation. The employer must ensure that employees on the ground in the vicinity of transmission structures are at a distance where step voltages would be insufficient to cause injury. Employees must not handle grounded conductors or equipment likely to become energized to hazardous voltages unless the employees are within an equipotential zone or protected by insulating equipment.
D. Protecting employees working on deenergized and grounded power lines. This Section III.D of Appendix C establishes guidelines to help employers comply with requirements in § 1910.269(n) for using protective grounding to protect employees working on deenergized power lines. Paragraph (n) of § 1910.269 applies to grounding of transmission and distribution lines and equipment for the purpose of protecting workers. Paragraph (n)(3) of § 1910.269 requires temporary protective grounds to be placed at such locations and arranged in such a manner that the employer can demonstrate will prevent exposure of each employee to hazardous differences in electric potential. 3 Sections III.D.1 and III.D.2 of this appendix provide guidelines that employers can use in making the demonstration required by § 1910.269(n)(3). Section III.D.1 of this appendix provides guidelines on how the employer can determine whether particular grounding practices expose employees to hazardous differences in electric potential. Section III.D.2 of this appendix describes grounding methods that the employer can use in lieu of an engineering analysis to make the demonstration required by § 1910.269(n)(3). The Occupational Safety and Health Administration will consider employers that comply with the criteria in this appendix as meeting § 1910.269(n)(3).
3 The protective grounding required by § 1910.269(n) limits to safe values the potential differences between accessible objects in each employee's work environment. Ideally, a protective grounding system would create a true equipotential zone in which every point is at the same electric potential. In practice, current passing through the grounding and bonding elements creates potential differences. If these potential differences are hazardous, the employer may not treat the zone as an equipotential zone.
Finally, Section III.D.3 of this appendix discusses other safety considerations that will help the employer comply with other requirements in § 1910.269(n). Following these guidelines will protect workers from hazards that can occur when a deenergized and grounded line becomes energized.
1. Determining safe body current limits. This Section III.D.1 of Appendix C provides guidelines on how an employer can determine whether any differences in electric potential to which workers could be exposed are hazardous as part of the demonstration required by § 1910.269(n)(3).
Institute of Electrical and Electronic Engineers (IEEE) Standard 1048-2003, IEEE Guide for Protective Grounding of Power Lines, provides the following equation for determining the threshold of ventricular fibrillation when the duration of the electric shock is limited:
where I is the current through the worker's body, and t is the duration of the current in seconds. This equation represents the ventricular fibrillation threshold for 95.5 percent of the adult population with a mass of 50 kilograms (110 pounds) or more. The equation is valid for current durations between 0.0083 to 3.0 seconds.
To use this equation to set safe voltage limits in an equipotential zone around the worker, the employer will need to assume a value for the resistance of the worker's body. IEEE Std 1048-2003 states that “total body resistance is usually taken as 1000 Ω for determining... body current limits.” However, employers should be aware that the impedance of a worker's body can be substantially less than that value. For instance, IEEE Std 1048-2003 reports a minimum hand-to-hand resistance of 610 ohms and an internal body resistance of 500 ohms. The internal resistance of the body better represents the minimum resistance of a worker's body when the skin resistance drops near zero, which occurs, for example, when there are breaks in the worker's skin, for instance, from cuts or from blisters formed as a result of the current from an electric shock, or when the worker is wet at the points of contact.
Employers may use the IEEE Std 1048-2003 equation to determine safe body current limits only if the employer protects workers from hazards associated with involuntary muscle reactions from electric shock (for example, the hazard to a worker from falling as a result of an electric shock). Moreover, the equation applies only when the duration of the electric shock is limited. If the precautions the employer takes, including those required by applicable standards, do not adequately protect employees from hazards associated with involuntary reactions from electric shock, a hazard exists if the induced voltage is sufficient to pass a current of 1 milliampere through a 500-ohm resistor. (The 500-ohm resistor represents the resistance of an employee. The 1-milliampere current is the threshold of perception.) Finally, if the employer protects employees from injury due to involuntary reactions from electric shock, but the duration of the electric shock is unlimited (that is, when the fault current at the work location will be insufficient to trip the devices protecting the circuit), a hazard exists if the resultant current would be more than 6 milliamperes (the recognized let-go threshold for workers 4 ).
4 Electric current passing through the body has varying effects depending on the amount of the current. At the let-go threshold, the current overrides a person's control over his or her muscles. At that level, an employee grasping an object will not be able to let go of the object. The let-go threshold varies from person to person; however, the recognized value for workers is 6 milliamperes.
2. Acceptable methods of grounding for employers that do not perform an engineering determination. The grounding methods presented in this section of this appendix ensure that differences in electric potential are as low as possible and, therefore, meet § 1910.269(n)(3) without an engineering determination of the potential differences. These methods follow two principles: (i) The grounding method must ensure that the circuit opens in the fastest available clearing time, and (ii) the grounding method must ensure that the potential differences between conductive objects in the employee's work area are as low as possible.
Paragraph (n)(3) of § 1910.269 does not require grounding methods to meet the criteria embodied in these principles. Instead, the paragraph requires that protective grounds be “placed at such locations and arranged in such a manner that the employer can demonstrate will prevent exposure of each employee to hazardous differences in electric potential.” However, when the employer's grounding practices do not follow these two principles, the employer will need to perform an engineering analysis to make the demonstration required by § 1910.269(n)(3).
i. Ensuring that the circuit opens in the fastest available clearing time. Generally, the higher the fault current, the shorter the clearing times for the same type of fault. Therefore, to ensure the fastest available clearing time, the grounding method must maximize the fault current with a low impedance connection to ground. The employer accomplishes this objective by grounding the circuit conductors to the best ground available at the worksite. Thus, the employer must ground to a grounded system neutral conductor, if one is present. A grounded system neutral has a direct connection to the system ground at the source, resulting in an extremely low impedance to ground. In a substation, the employer may instead ground to the substation grid, which also has an extremely low impedance to the system ground and, typically, is connected to a grounded system neutral when one is present. Remote system grounds, such as pole and tower grounds, have a higher impedance to the system ground than grounded system neutrals and substation grounding grids; however, the employer may use a remote ground when lower impedance grounds are not available. In the absence of a grounded system neutral, substation grid, and remote ground, the employer may use a temporary driven ground at the worksite.
In addition, if employees are working on a three-phase system, the grounding method must short circuit all three phases. Short circuiting all phases will ensure faster clearing and lower the current through the grounding cable connecting the deenergized line to ground, thereby lowering the voltage across that cable. The short circuit need not be at the worksite; however, the employer must treat any conductor that is not grounded at the worksite as energized because the ungrounded conductors will be energized at fault voltage during a fault.
ii. Ensuring that the potential differences between conductive objects in the employee's work area are as low as possible. To achieve as low a voltage as possible across any two conductive objects in the work area, the employer must bond all conductive objects in the work area. This section of this appendix discusses how to create a zone that minimizes differences in electric potential between conductive objects in the work area.
The employer must use bonding cables to bond conductive objects, except for metallic objects bonded through metal-to-metal contact. The employer must ensure that metal-to-metal contacts are tight and free of contamination, such as oxidation, that can increase the impedance across the connection. For example, a bolted connection between metal lattice tower members is acceptable if the connection is tight and free of corrosion and other contamination. Figure 4 shows how to create an equipotential zone for metal lattice towers.
Wood poles are conductive objects. The poles can absorb moisture and conduct electricity, particularly at distribution and transmission voltages. Consequently, the employer must either: (1) Provide a conductive platform, bonded to a grounding cable, on which the worker stands or (2) use cluster bars to bond wood poles to the grounding cable. The employer must ensure that employees install the cluster bar below, and close to, the worker's feet. The inner portion of the wood pole is more conductive than the outer shell, so it is important that the cluster bar be in conductive contact with a metal spike or nail that penetrates the wood to a depth greater than or equal to the depth the worker's climbing gaffs will penetrate the wood. For example, the employer could mount the cluster bar on a bare pole ground wire fastened to the pole with nails or staples that penetrate to the required depth. Alternatively, the employer may temporarily nail a conductive strap to the pole and connect the strap to the cluster bar. Figure 5 shows how to create an equipotential zone for wood poles.
For underground systems, employers commonly install grounds at the points of disconnection of the underground cables. These grounding points are typically remote from the manhole or underground vault where employees will be working on the cable. Workers in contact with a cable grounded at a remote location can experience hazardous potential differences if the cable becomes energized or if a fault occurs on a different, but nearby, energized cable. The fault current causes potential gradients in the earth, and a potential difference will exist between the earth where the worker is standing and the earth where the cable is grounded. Consequently, to create an equipotential zone for the worker, the employer must provide a means of connecting the deenergized cable to ground at the worksite by having the worker stand on a conductive mat bonded to the deenergized cable. If the cable is cut, the employer must install a bond across the opening in the cable or install one bond on each side of the opening to ensure that the separate cable ends are at the same potential. The employer must protect the worker from any hazardous differences in potential any time there is no bond between the mat and the cable (for example, before the worker installs the bonds).
3. Other safety-related considerations. To ensure that the grounding system is safe and effective, the employer should also consider the following factors: 5
5 This appendix only discusses factors that relate to ensuring an equipotential zone for employees. The employer must consider other factors in selecting a grounding system that is capable of conducting the maximum fault current that could flow at the point of grounding for the time necessary to clear the fault, as required by § 1910.269(n)(4)(i). IEEE Std 1048-2003 contains guidelines for selecting and installing grounding equipment that will meet § 1910.269(n)(4)(i).
i. Maintenance of grounding equipment. It is essential that the employer properly maintain grounding equipment. Corrosion in the connections between grounding cables and clamps and on the clamp surface can increase the resistance of the cable, thereby increasing potential differences. In addition, the surface to which a clamp attaches, such as a conductor or tower member, must be clean and free of corrosion and oxidation to ensure a low-resistance connection. Cables must be free of damage that could reduce their current-carrying capacity so that they can carry the full fault current without failure. Each clamp must have a tight connection to the cable to ensure a low resistance and to ensure that the clamp does not separate from the cable during a fault.
ii. Grounding cable length and movement. The electromagnetic forces on grounding cables during a fault increase with increasing cable length. These forces can cause the cable to move violently during a fault and can be high enough to damage the cable or clamps and cause the cable to fail. In addition, flying cables can injure workers. Consequently, cable lengths should be as short as possible, and grounding cables that might carry high fault current should be in positions where the cables will not injure workers during a fault.
Appendix D to § 1910.269—Methods of Inspecting and Testing Wood Poles
I. Introduction
When employees are to perform work on a wood pole, it is important to determine the condition of the pole before employees climb it. The weight of the employee, the weight of equipment to be installed, and other working stresses (such as the removal or retensioning of conductors) can lead to the failure of a defective pole or a pole that is not designed to handle the additional stresses. 1 For these reasons, it is essential that, before an employee climbs a wood pole, the employer ascertain that the pole is capable of sustaining the stresses of the work. The determination that the pole is capable of sustaining these stresses includes an inspection of the condition of the pole.
1 A properly guyed pole in good condition should, at a minimum, be able to handle the weight of an employee climbing it.
If the employer finds the pole to be unsafe to climb or to work from, the employer must secure the pole so that it does not fail while an employee is on it. The employer can secure the pole by a line truck boom, by ropes or guys, or by lashing a new pole alongside it. If a new one is lashed alongside the defective pole, employees should work from the new one.
II. Inspecting Wood Poles
A qualified employee should inspect wood poles for the following conditions: 2
2 The presence of any of these conditions is an indication that the pole may not be safe to climb or to work from. The employee performing the inspection must be qualified to make a determination as to whether it is safe to perform the work without taking additional precautions.
A. General condition. Buckling at the ground line or an unusual angle with respect to the ground may indicate that the pole has rotted or is broken.
B. Cracks. Horizontal cracks perpendicular to the grain of the wood may weaken the pole. Vertical cracks, although not normally considered to be a sign of a defective pole, can pose a hazard to the climber, and the employee should keep his or her gaffs away from them while climbing.
C. Holes. Hollow spots and woodpecker holes can reduce the strength of a wood pole.
D. Shell rot and decay. Rotting and decay are cutout hazards and possible indications of the age and internal condition of the pole.
E. Knots. One large knot or several smaller ones at the same height on the pole may be evidence of a weak point on the pole.
F. Depth of setting. Evidence of the existence of a former ground line substantially above the existing ground level may be an indication that the pole is no longer buried to a sufficient depth.
G. Soil conditions. Soft, wet, or loose soil around the base of the pole may indicate that the pole will not support any change in stress.
H. Burn marks. Burning from transformer failures or conductor faults could damage the pole so that it cannot withstand changes in mechanical stress.
III. Testing Wood Poles
The following tests, which are from § 1910.268(n)(3), are acceptable methods of testing wood poles:
A. Hammer test. Rap the pole sharply with a hammer weighing about 1.4 kg (3 pounds), starting near the ground line and continuing upwards circumferentially around the pole to a height of approximately 1.8 meters (6 feet). The hammer will produce a clear sound and rebound sharply when striking sound wood. Decay pockets will be indicated by a dull sound or a less pronounced hammer rebound. Also, prod the pole as near the ground line as possible using a pole prod or a screwdriver with a blade at least 127 millimeters (5 inches) long. If substantial decay is present, the pole is unsafe.
B. Rocking test. Apply a horizontal force to the pole and attempt to rock it back and forth in a direction perpendicular to the line. Exercise caution to avoid causing power lines to swing together. Apply the force to the pole either by pushing it with a pike pole or pulling the pole with a rope. If the pole cracks during the test, it is unsafe.
Appendix E to § 1910.269—Protection From Flames and Electric Arcs
I. Introduction
Paragraph (l)(8) of § 1910.269 addresses protecting employees from flames and electric arcs. This paragraph requires employers to: (1) Assess the workplace for flame and electric-arc hazards (paragraph (l)(8)(i)); (2) estimate the available heat energy from electric arcs to which employees would be exposed (paragraph (l)(8)(ii)); (3) ensure that employees wear clothing that will not melt, or ignite and continue to burn, when exposed to flames or the estimated heat energy (paragraph (l)(8)(iii)); and (4) ensure that employees wear flame-resistant clothing 1 and protective clothing and other protective equipment that has an arc rating greater than or equal to the available heat energy under certain conditions (paragraphs (l)(8)(iv) and (l)(8)(v)). This appendix contains information to help employers estimate available heat energy as required by § 1910.269(l)(8)(ii), select protective clothing and other protective equipment with an arc rating suitable for the available heat energy as required by § 1910.269(l)(8)(v), and ensure that employees do not wear flammable clothing that could lead to burn injury as addressed by §§ 1910.269(l)(8)(iii) and (l)(8)(iv).
1 Flame-resistant clothing includes clothing that is inherently flame resistant and clothing chemically treated with a flame retardant. (See ASTM F1506-10a, Standard Performance Specification for Flame Resistant Textile Materials for Wearing Apparel for Use by Electrical Workers Exposed to Momentary Electric Arc and Related Thermal Hazards, and ASTM F1891-12 Standard Specification for Arc and Flame Resistant Rainwear. )
II. Assessing the Workplace for Flame and Electric-Arc Hazards
Paragraph (l)(8)(i) of § 1910.269 requires the employer to assess the workplace to identify employees exposed to hazards from flames or from electric arcs. This provision ensures that the employer evaluates employee exposure to flames and electric arcs so that employees who face such exposures receive the required protection. The employer must conduct an assessment for each employee who performs work on or near exposed, energized parts of electric circuits.
A. Assessment Guidelines
Sources electric arcs. Consider possible sources of electric arcs, including:
• Energized circuit parts not guarded or insulated,
• Switching devices that produce electric arcs in normal operation,
• Sliding parts that could fault during operation (for example, rack-mounted circuit breakers), and
• Energized electric equipment that could fail (for example, electric equipment with damaged insulation or with evidence of arcing or overheating).
Exposure to flames. Identify employees exposed to hazards from flames. Factors to consider include:
• The proximity of employees to open flames, and
• For flammable material in the work area, whether there is a reasonable likelihood that an electric arc or an open flame can ignite the material.
Probability that an electric arc will occur. Identify employees exposed to electric-arc hazards. The Occupational Safety and Health Administration will consider an employee exposed to electric-arc hazards if there is a reasonable likelihood that an electric arc will occur in the employee's work area, in other words, if the probability of such an event is higher than it is for the normal operation of enclosed equipment. Factors to consider include:
• For energized circuit parts not guarded or insulated, whether conductive objects can come too close to or fall onto the energized parts,
• For exposed, energized circuit parts, whether the employee is closer to the part than the minimum approach distance established by the employer (as permitted by § 1910.269(l)(3)(iii)).
• Whether the operation of electric equipment with sliding parts that could fault during operation is part of the normal operation of the equipment or occurs during servicing or maintenance, and
• For energized electric equipment, whether there is evidence of impending failure, such as evidence of arcing or overheating.
B. Examples
| Task | Is employee exposed to flame or electric-arc hazard? | |
|---|---|---|
| Normal operation of enclosed equipment, such as closing or opening a switch | The employer properly installs and maintains enclosed equipment, and there is no evidence of impending failure | No. |
| There is evidence of arcing or overheating | Yes. | |
| Parts of the equipment are loose or sticking, or the equipment otherwise exhibits signs of lack of maintenance | Yes. | |
| Servicing electric equipment, such as racking in a circuit breaker or replacing a switch | Yes. | |
| Inspection of electric equipment with exposed energized parts. | The employee is not holding conductive objects and remains outside the minimum approach distance established by the employer | No. |
| The employee is holding a conductive object, such as a flashlight, that could fall or otherwise contact energized parts (irrespective of whether the employee maintains the minimum approach distance) | Yes. | |
| The employee is closer than the minimum approach distance established by the employer (for example, when wearing rubber insulating gloves or rubber insulating gloves and sleeves) | Yes. | |
| Using open flames, for example, in wiping cable splice sleeves | Yes. |
III. Protection Against Burn Injury
A. Estimating Available Heat Energy
Calculation methods. Paragraph (l)(8)(ii) of § 1910.269 provides that, for each employee exposed to an electric-arc hazard, the employer must make a reasonable estimate of the heat energy to which the employee would be exposed if an arc occurs. Table 2 lists various methods of calculating values of available heat energy from an electric circuit. The Occupational Safety and Health Administration does not endorse any of these specific methods. Each method requires the input of various parameters, such as fault current, the expected length of the electric arc, the distance from the arc to the employee, and the clearing time for the fault (that is, the time the circuit protective devices take to open the circuit and clear the fault). The employer can precisely determine some of these parameters, such as the fault current and the clearing time, for a given system. The employer will need to estimate other parameters, such as the length of the arc and the distance between the arc and the employee, because such parameters vary widely.
| 1. Standard for Electrical Safety Requirements for Employee Workplaces, NFPA 70E-2012, Annex D, “Sample Calculation of Flash Protection Boundary.” |
|---|
| 2. Doughty, T.E., Neal, T.E., and Floyd II, H.L., “Predicting Incident Energy to Better Manage the Electric Arc Hazard on 600 V Power Distribution Systems,” Record of Conference Papers IEEE IAS 45th Annual Petroleum and Chemical Industry Conference, September 28-30, 1998. |
| 3. Guide for Performing Arc-Flash Hazard Calculations, IEEE Std 1584-2002, 1584a-2004 (Amendment 1 to IEEE Std 1584-2002), and 1584b-2011 (Amendment 2: Changes to Clause 4 of IEEE Std 1584-2002).* |
| 4. ARCPRO, a commercially available software program developed by Kinectrics, Toronto, ON, CA. |
| * This appendix refers to IEEE Std 1584-2002 with both amendments as IEEE Std 1584b-2011. |
The amount of heat energy calculated by any of the methods is approximately inversely proportional to the square of the distance between the employee and the arc. In other words, if the employee is very close to the arc, the heat energy is very high; but if the employee is just a few more centimeters away, the heat energy drops substantially. Thus, estimating the distance from the arc to the employee is key to protecting employees.
The employer must select a method of estimating incident heat energy that provides a reasonable estimate of incident heat energy for the exposure involved. Table 3 shows which methods provide reasonable estimates for various exposures.
| Incident-energy calculation method | 600 V and Less 2 | 601 V to 15 kV 2 | More than 15 kV | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 1Φ | 3Φa | 3Φb | 1Φ | 3Φa | 3Φb | 1Φ | 3Φa | 3Φb | |
| NFPA 70E-2012 Annex D (Lee equation) | Y-C | Y | N | Y-C | Y-C | N | N 3 | N 3 | N 3 |
| Doughty, Neal, and Floyd | Y-C | Y | Y | N | N | N | N | N | N |
| IEEE Std 1584b-2011 | Y | Y | Y | Y | Y | Y | N | N | N |
| ARCPRO | Y | N | N | Y | N | N | Y | Y 4 | Y 4 |
| Key: | |||||||||
| 1Φ: Single-phase arc in open air. | |||||||||
| 3Φa: Three-phase arc in open air. | |||||||||
| 3Φb: Three-phase arc in an enclosure (box). | |||||||||
| Y: Acceptable; produces a reasonable estimate of incident heat energy from this type of electric arc. | |||||||||
| N: Not acceptable; does not produce a reasonable estimate of incident heat energy from this type of electric arc. | |||||||||
| Y-C: Acceptable; produces a reasonable, but conservative, estimate of incident heat energy from this type of electric arc. | |||||||||
| Notes: | |||||||||
| 1 Although the Occupational Safety and Health Administration will consider these methods reasonable for enforcement purposes when employers use the methods in accordance with this table, employers should be aware that the listed methods do not necessarily result in estimates that will provide full protection from internal faults in transformers and similar equipment or from arcs in underground manholes or vaults. | |||||||||
| 2 At these voltages, the presumption is that the arc is three-phase unless the employer can demonstrate that only one phase is present or that the spacing of the phases is sufficient to prevent a multiphase arc from occurring. | |||||||||
| 3 Although the Occupational Safety and Health Administration will consider this method acceptable for purposes of assessing whether incident energy exceeds 2.0 cal/cm 2 , the results at voltages of more than 15 kilovolts are extremely conservative and unrealistic. | |||||||||
| 4 The Occupational Safety and Health Administration will deem the results of this method reasonable when the employer adjusts them using the conversion factors for three-phase arcs in open air or in an enclosure, as indicated in the program's instructions. |
Selecting a reasonable distance from the employee to the arc. In estimating available heat energy, the employer must make some reasonable assumptions about how far the employee will be from the electric arc. Table 4 lists reasonable distances from the employee to the electric arc. The distances in Table 4 are consistent with national consensus standards, such as the Institute of Electrical and Electronic Engineers' National Electrical Safety Code, ANSI/IEEE C2-2012, and IEEE Guide for Performing Arc-Flash Hazard Calculations, IEEE Std 1584b-2011. The employer is free to use other reasonable distances, but must consider equipment enclosure size and the working distance to the employee in selecting a distance from the employee to the arc. The Occupational Safety and Health Administration will consider a distance reasonable when the employer bases it on equipment size and working distance.
| Class of equipment | Single-phase arc mm (inches) | Three-phase arc mm (inches) |
|---|---|---|
| Cable | * NA | 455 (18) |
| Low voltage MCCs and panelboards | NA | 455 (18) |
| Low-voltage switchgear | NA | 610 (24) |
| 5-kV switchgear | NA | 910 (36) |
| 15-kV switchgear | NA | 910 (36) |
| Single conductors in air (up to 46 kilovolts), work with rubber insulating gloves | 380 (15) | NA |
| Single conductors in air, work with live-line tools and live-line barehand work | MAD − (2 × kV × 2.54) ( MAD − (2 × kV /10)) † | NA |
| * NA = not applicable. | ||
| † The terms in this equation are: | ||
| MAD = The applicable minimum approach distance, and | ||
| kV = The system voltage in kilovolts. |
Selecting a reasonable arc gap. For a single-phase arc in air, the electric arc will almost always occur when an energized conductor approaches too close to ground. Thus, an employer can determine the arc gap, or arc length, for these exposures by the dielectric strength of air and the voltage on the line. The dielectric strength of air is approximately 10 kilovolts for every 25.4 millimeters (1 inch). For example, at 50 kilovolts, the arc gap would be 50 ÷ 10 × 25.4 (or 50 × 2.54), which equals 127 millimeters (5 inches).
For three-phase arcs in open air and in enclosures, the arc gap will generally be dependent on the spacing between parts energized at different electrical potentials. Documents such as IEEE Std 1584b-2011 provide information on these distances. Employers may select a reasonable arc gap from Table 5, or they may select any other reasonable arc gap based on sparkover distance or on the spacing between (1) live parts at different potentials or (2) live parts and grounded parts (for example, bus or conductor spacings in equipment). In any event, the employer must use an estimate that reasonably resembles the actual exposures faced by the employee.
| Class of equipment | Single-phase arc mm (inches) | Three-phase arc mm 1 (inches) |
|---|---|---|
| Cable | NA 2 | 13 (0.5). |
| Low voltage MCCs and panelboards | NA | 25 (1.0). |
| Low-voltage switchgear | NA | 32 (1.25). |
| 5-kV switchgear | NA | 104 (4.0). |
| 15-kV switchgear | NA | 152 (6.0). |
| Single conductors in air, 15 kV and less. | 51 (2.0) | Phase conductor spacing. |
| Single conductor in air, more than 15 kV | Voltage in kV × 2.54 (Voltage in kV × 0.1), but no less than 51 mm (2 inches) | Phase conductor spacing. |
| 1 Source: IEEE Std 1584b-2011. | ||
| 2 NA = not applicable. |
Making estimates over multiple system areas. The employer need not estimate the heat-energy exposure for every job task performed by each employee. Paragraph (l)(8)(ii) of § 1910.269 permits the employer to make broad estimates that cover multiple system areas provided that: (1) The employer uses reasonable assumptions about the energy-exposure distribution throughout the system, and (2) the estimates represent the maximum exposure for those areas. For example, the employer can use the maximum fault current and clearing time to cover several system areas at once.
Incident heat energy for single-phase-to-ground exposures. Table 6 and Table 7 provide incident heat energy levels for open-air, phase-to-ground electric-arc exposures typical for overhead systems. 2 Table 6 presents estimates of available energy for employees using rubber insulating gloves to perform work on overhead systems operating at 4 to 46 kilovolts. The table assumes that the employee will be 380 millimeters (15 inches) from the electric arc, which is a reasonable estimate for rubber insulating glove work. Table 6 also assumes that the arc length equals the sparkover distance for the maximum transient overvoltage of each voltage range. 3 To use the table, an employer would use the voltage, maximum fault current, and maximum clearing time for a system area and, using the appropriate voltage range and fault-current and clearing-time values corresponding to the next higher values listed in the table, select the appropriate heat energy (4, 5, 8, or 12 cal/cm 2 ) from the table. For example, an employer might have a 12,470-volt power line supplying a system area. The power line can supply a maximum fault current of 8 kiloamperes with a maximum clearing time of 10 cycles. For rubber glove work, this system falls in the 4.0-to-15.0-kilovolt range; the next-higher fault current is 10 kA (the second row in that voltage range); and the clearing time is under 18 cycles (the first column to the right of the fault current column). Thus, the available heat energy for this part of the system will be 4 cal/cm 2 or less (from the column heading), and the employer could select protection with a 5-cal/cm 2 rating to meet § 1910.269(l)(8)(v). Alternatively, an employer could select a base incident-energy value and ensure that the clearing times for each voltage range and fault current listed in the table do not exceed the corresponding clearing time specified in the table. For example, an employer that provides employees with arc-flash protective equipment rated at 8 cal/cm 2 can use the table to determine if any system area exceeds 8 cal/cm 2 by checking the clearing time for the highest fault current for each voltage range and ensuring that the clearing times do not exceed the values specified in the 8-cal/cm 2 column in the table.
2 The Occupational Safety and Health Administration used metric values to calculate the clearing times in Table 6 and Table 7. An employer may use English units to calculate clearing times instead even though the results will differ slightly.
3 The Occupational Safety and Health Administration based this assumption, which is more conservative than the arc length specified in Table 5, on Table 410-2 of the 2012 NESC.
4 The dielectric strength of air is about 10 kilovolts for every 25.4 millimeters (1 inch). Thus, the employer can estimate the arc length in millimeters to be the phase-to-ground voltage in kilovolts multiplied by 2.54 (or voltage (in kilovolts) × 2.54).
The employer will need to use other methods for estimating available heat energy in situations not addressed by Table 6 or Table 7. The calculation methods listed in Table 2 and the guidance provided in Table 3 will help employers do this. For example, employers can use IEEE Std 1584b-2011 to estimate the available heat energy (and to select appropriate protective equipment) for many specific conditions, including lower-voltage, phase-to-phase arc, and enclosed arc exposures.
| Voltage range (kV) ** | Fault current (kA) | Maximum clearing time (cycles) | |||
|---|---|---|---|---|---|
| 4 cal/cm 2 | 5 cal/cm 2 | 8 cal/cm 2 | 12 cal/cm 2 | ||
| 4.0 to 15.0 | 5 | 46 | 58 | 92 | 138 |
| 10 | 18 | 22 | 36 | 54 | |
| 15 | 10 | 12 | 20 | 30 | |
| 20 | 6 | 8 | 13 | 19 | |
| 15.1 to 25.0 | 5 | 28 | 34 | 55 | 83 |
| 10 | 11 | 14 | 23 | 34 | |
| 15 | 7 | 8 | 13 | 20 | |
| 20 | 4 | 5 | 9 | 13 | |
| 25.1 to 36.0 | 5 | 21 | 26 | 42 | 62 |
| 10 | 9 | 11 | 18 | 26 | |
| 15 | 5 | 6 | 10 | 16 | |
| 20 | 4 | 4 | 7 | 11 | |
| 36.1 to 46.0 | 5 | 16 | 20 | 32 | 48 |
| 10 | 7 | 9 | 14 | 21 | |
| 15 | 4 | 5 | 8 | 13 | |
| 20 | 3 | 4 | 6 | 9 | |
| Notes: * This table is for open-air, phase-to-ground electric-arc exposures. It is not for phase-to-phase arcs or enclosed arcs (arc in a box). | |||||
| † The table assumes that the employee will be 380 mm (15 in.) from the electric arc. The table also assumes the arc length to be the sparkover distance for the maximum transient overvoltage of each voltage range (see Appendix B to § 1910.269), as follows: | |||||
| 4.0 to 15.0 kV 51 mm (2 in.) | |||||
| 15.1 to 25.0 kV 102 mm (4 in.) | |||||
| 25.1 to 36.0 kV 152 mm (6 in.) | |||||
| 36.1 to 46.0 kV 229 mm (9 in.) | |||||
| ‡The Occupational Safety and Health Administration calculated the values in this table using the ARCPRO method listed in Table 2. | |||||
| ** The voltage range is the phase-to-phase system voltage. |
| Voltage range (kV) ** | Fault current (kA) | Maximum clearing time (cycles) | |||
|---|---|---|---|---|---|
| 4 cal/cm 2 | 5 cal/cm 2 | 8 cal/cm 2 | 12 cal/cm 2 | ||
| 4.0 to 15.0 | 5 | 197 | 246 | 394 | 591 |
| 10 | 73 | 92 | 147 | 220 | |
| 15 | 39 | 49 | 78 | 117 | |
| 20 | 24 | 31 | 49 | 73 | |
| 15.1 to 25.0 | 5 | 197 | 246 | 394 | 591 |
| 10 | 75 | 94 | 150 | 225 | |
| 15 | 41 | 51 | 82 | 122 | |
| 20 | 26 | 33 | 52 | 78 | |
| 25.1 to 36.0 | 5 | 138 | 172 | 275 | 413 |
| 10 | 53 | 66 | 106 | 159 | |
| 15 | 30 | 37 | 59 | 89 | |
| 20 | 19 | 24 | 38 | 58 | |
| 36.1 to 46.0 | 5 | 129 | 161 | 257 | 386 |
| 10 | 51 | 64 | 102 | 154 | |
| 15 | 29 | 36 | 58 | 87 | |
| 20 | 19 | 24 | 38 | 57 | |
| 46.1 to 72.5 | 20 | 18 | 23 | 36 | 55 |
| 30 | 10 | 13 | 20 | 30 | |
| 40 | 6 | 8 | 13 | 19 | |
| 50 | 4 | 6 | 9 | 13 | |
| 72.6 to 121.0 | 20 | 10 | 12 | 20 | 30 |
| 30 | 6 | 7 | 11 | 17 | |
| 40 | 4 | 5 | 7 | 11 | |
| 50 | 3 | 3 | 5 | 8 | |
| 121.1 to 145.0 | 20 | 12 | 15 | 24 | 35 |
| 30 | 7 | 9 | 15 | 22 | |
| 40 | 5 | 6 | 10 | 15 | |
| 50 | 4 | 5 | 8 | 11 | |
| 145.1 to 169.0 | 20 | 12 | 15 | 24 | 36 |
| 30 | 7 | 9 | 15 | 22 | |
| 40 | 5 | 7 | 10 | 16 | |
| 50 | 4 | 5 | 8 | 12 | |
| 169.1 to 242.0 | 20 | 13 | 17 | 27 | 40 |
| 30 | 8 | 10 | 17 | 25 | |
| 40 | 6 | 7 | 12 | 17 | |
| 50 | 4 | 5 | 9 | 13 | |
| 242.1 to 362.0 | 20 | 25 | 32 | 51 | 76 |
| 30 | 16 | 19 | 31 | 47 | |
| 40 | 11 | 14 | 22 | 33 | |
| 50 | 8 | 10 | 16 | 25 | |
| 362.1 to 420.0 | 20 | 12 | 15 | 25 | 37 |
| 30 | 8 | 10 | 15 | 23 | |
| 40 | 5 | 7 | 11 | 16 | |
| 50 | 4 | 5 | 8 | 12 | |
| 420.1 to 550.0 | 20 | 23 | 29 | 47 | 70 |
| 30 | 14 | 18 | 29 | 43 | |
| 40 | 10 | 13 | 20 | 30 | |
| 50 | 8 | 9 | 15 | 23 | |
| 550.1 to 800.0 | 20 | 25 | 31 | 50 | 75 |
| 30 | 15 | 19 | 31 | 46 | |
| 40 | 11 | 13 | 21 | 32 | |
| 50 | 8 | 10 | 16 | 24 | |
| Notes: | |||||
| * This table is for open-air, phase-to-ground electric-arc exposures. It is not for phase-to-phase arcs or enclosed arcs (arc in a box). | |||||
| † The table assumes the arc length to be the sparkover distance for the maximum phase-to-ground voltage of each voltage range (see Appendix B to this section). The table also assumes that the employee will be the minimum approach distance minus twice the arc length from the electric arc. | |||||
| ‡ The Occupational Safety and Health Administration calculated the values in this table using the ARCPRO method listed in Table 2. | |||||
| # For voltages of more than 72.6 kV, employers may use this table only when the minimum approach distance established under § 1910.269(l)(3)(i) is greater than or equal to the following values: | |||||
| 72.6 to 121.0 kV 1.02 m. | |||||
| 121.1 to 145.0 kV 1.16 m. | |||||
| 145.1 to 169.0 kV 1.30 m. | |||||
| 169.1 to 242.0 kV 1.72 m. | |||||
| 242.1 to 362.0 kV 2.76 m. | |||||
| 362.1 to 420.0 kV 2.50 m. | |||||
| 420.1 to 550.0 kV 3.62 m. | |||||
| 550.1 to 800.0 kV 4.83 m. | |||||
| ** The voltage range is the phase-to-phase system voltage. |
B. Selecting Protective Clothing and Other Protective Equipment
Paragraph (l)(8)(v) of § 1910.269 requires employers, in certain situations, to select protective clothing and other protective equipment with an arc rating that is greater than or equal to the incident heat energy estimated under § 1910.269(l)(8)(ii). Based on laboratory testing required by ASTM F1506-10a, the expectation is that protective clothing with an arc rating equal to the estimated incident heat energy will be capable of preventing second-degree burn injury to an employee exposed to that incident heat energy from an electric arc. Note that actual electric-arc exposures may be more or less severe than the estimated value because of factors such as arc movement, arc length, arcing from reclosing of the system, secondary fires or explosions, and weather conditions. Additionally, for arc rating based on the fabric's arc thermal performance value 5 (ATPV), a worker exposed to incident energy at the arc rating has a 50-percent chance of just barely receiving a second-degree burn. Therefore, it is possible (although not likely) that an employee will sustain a second-degree (or worse) burn wearing clothing conforming to § 1910.269(l)(8)(v) under certain circumstances. However, reasonable employer estimates and maintaining appropriate minimum approach distances for employees should limit burns to relatively small burns that just barely extend beyond the epidermis (that is, just barely a second-degree burn). Consequently, protective clothing and other protective equipment meeting § 1910.269(l)(8)(v) will provide an appropriate degree of protection for an employee exposed to electric-arc hazards.
5 ASTM F1506-10a defines “arc thermal performance value” as “the incident energy on a material or a multilayer system of materials that results in a 50% probability that sufficient heat transfer through the tested specimen is predicted to cause the onset of a second-degree skin burn injury based on the Stoll [footnote] curve, cal/cm 2.” The footnote to this definition reads: “Derived from: Stoll, A. M., and Chianta, M. A., `Method and Rating System for Evaluations of Thermal Protection,' Aerospace Medicine, Vol 40, 1969, pp. 1232-1238 and Stoll, A. M., and Chianta, M. A., `Heat Transfer through Fabrics as Related to Thermal Injury,' Transactions—New York Academy of Sciences, Vol 33(7), Nov. 1971, pp. 649-670.”
Paragraph (l)(8)(v) of § 1910.269 does not require arc-rated protection for exposures of 2 cal/cm 2 or less. Untreated cotton clothing will reduce a 2-cal/cm 2 exposure below the 1.2- to 1.5-cal/cm 2 level necessary to cause burn injury, and this material should not ignite at such low heat energy levels. Although § 1910.269(l)(8)(v) does not require clothing to have an arc rating when exposures are 2 cal/cm 2 or less, § 1910.269(l)(8)(iv) requires the outer layer of clothing to be flame resistant under certain conditions, even when the estimated incident heat energy is less than 2 cal/cm 2, as discussed later in this appendix. Additionally, it is especially important to ensure that employees do not wear undergarments made from fabrics listed in the note to § 1910.269(l)(8)(iii) even when the outer layer is flame resistant or arc rated. These fabrics can melt or ignite easily when an electric arc occurs. Logos and name tags made from non-flame-resistant material can adversely affect the arc rating or the flame-resistant characteristics of arc-rated or flame-resistant clothing. Such logos and name tags may violate § 1910.269(l)(8)(iii), (l)(8)(iv), or (l)(8)(v).
Paragraph (l)(8)(v) of § 1910.269 requires that arc-rated protection cover the employee's entire body, with limited exceptions for the employee's hands, feet, face, and head. Paragraph (l)(8)(v)(A) of § 1910.269 provides that arc-rated protection is not necessary for the employee's hands under the following conditions:
| For any estimated incident heat energy | When the employee is wearing rubber insulating gloves with protectors. |
|---|---|
| If the estimated incident heat energy does not exceed 14 cal/cm 2 | When the employee is wearing heavy-duty leather work gloves with a weight of at least 407 gm/m 2 (12 oz/yd 2 ). |
Paragraph (l)(8)(v)(B) of § 1910.269 provides that arc-rated protection is not necessary for the employee's feet when the employee is wearing heavy-duty work shoes or boots. Finally, § 1910.269(l)(8)(v)(C), (l)(8)(v)(D), and (l)(8)(v)(E) require arc-rated head and face protection as follows:
| Exposure | Minimum head and face protection | ||
|---|---|---|---|
| None * | Arc-rated faceshield with a minimum rating of 8 cal/cm 2 * | Arc-rated hood or faceshield with balaclava | |
| Single-phase, open air | 2-8 cal/cm 2 | 9-12 cal/cm 2 | 13 cal/cm 2 or higher †. |
| Three-phase | 2-4 cal/cm 2 | 5-8 cal/cm 2 | 9 cal/cm 2 or higher ‡. |
| * These ranges assume that employees are wearing hardhats meeting the specifications in § 1910.135 or § 1926.100(b)(2), as applicable. | |||
| † The arc rating must be a minimum of 4 cal/cm 2 less than the estimated incident energy. Note that § 1910.269(l)(8)(v)(E) permits this type of head and face protection, with a minimum arc rating of 4 cal/cm 2 less than the estimated incident energy, at any incident energy level. | |||
| ‡ Note that § 1910.269(l)(8)(v) permits this type of head and face protection at any incident energy level. |
IV. Protection Against Ignition
Paragraph (l)(8)(iii) of § 1910.269 prohibits clothing that could melt onto an employee's skin or that could ignite and continue to burn when exposed to flames or to the available heat energy estimated by the employer under § 1910.269(l)(8)(ii). Meltable fabrics, such as acetate, nylon, polyester, and polypropylene, even in blends, must be avoided. When these fibers melt, they can adhere to the skin, thereby transferring heat rapidly, exacerbating burns, and complicating treatment. These outcomes can result even if the meltable fabric is not directly next to the skin. The remainder of this section focuses on the prevention of ignition.
Paragraph (l)(8)(v) of § 1910.269 generally requires protective clothing and other protective equipment with an arc rating greater than or equal to the employer's estimate of available heat energy. As explained earlier in this appendix, untreated cotton is usually acceptable for exposures of 2 cal/cm 2 or less. 6 If the exposure is greater than that, the employee generally must wear flame-resistant clothing with a suitable arc rating in accordance with § 1910.269(l)(8)(iv) and (l)(8)(v). However, even if an employee is wearing a layer of flame-resistant clothing, there are circumstances under which flammable layers of clothing would be uncovered, and an electric arc could ignite them. For example, clothing ignition is possible if the employee is wearing flammable clothing under the flame-resistant clothing and the underlayer is uncovered because of an opening in the flame-resistant clothing. Thus, for purposes of § 1910.269(l)(8)(iii), it is important for the employer to consider the possibility of clothing ignition even when an employee is wearing flame-resistant clothing with a suitable arc rating.
6 See § 1910.269(l)(8)(iv)(A), (l)(8)(iv)(B), and (l)(8)(iv)(C) for conditions under which employees must wear flame-resistant clothing as the outer layer of clothing even when the incident heat energy does not exceed 2 cal/cm 2.
Under § 1910.269(l)(8)(iii), employees may not wear flammable clothing in conjunction with flame-resistant clothing if the flammable clothing poses an ignition hazard. 7 Although outer flame-resistant layers may not have openings that expose flammable inner layers, when an outer flame-resistant layer would be unable to resist breakopen, 8 the next (inner) layer must be flame-resistant if it could ignite.
7 Paragraph (l)(8)(iii) of § 1910.269 prohibits clothing that could ignite and continue to burn when exposed to the heat energy estimated under paragraph (l)(8)(ii) of that section.
8 Breakopen occurs when a hole, tear, or crack develops in the exposed fabric such that the fabric no longer effectively blocks incident heat energy.
Non-flame-resistant clothing can ignite even when the heat energy from an electric arc is insufficient to ignite the clothing. For example, nearby flames can ignite an employee's clothing; and, even in the absence of flames, electric arcs pose ignition hazards beyond the hazard of ignition from incident energy under certain conditions. In addition to requiring flame-resistant clothing when the estimated incident energy exceeds 2.0 cal/cm 2, § 1910.269(l)(8)(iv) requires flame-resistant clothing when: The employee is exposed to contact with energized circuit parts operating at more than 600 volts (§ 1910.269(l)(8)(iv)(A)), an electric arc could ignite flammable material in the work area that, in turn, could ignite the employee's clothing (§ 1910.269(l)(8)(iv)(B)), and molten metal or electric arcs from faulted conductors in the work area could ignite the employee's clothing (§ 1910.269(l)(8)(iv)(C)). For example, grounding conductors can become a source of heat energy if they cannot carry fault current without failure. The employer must consider these possible sources of electric arcs 9 in determining whether the employee's clothing could ignite under § 1910.269(l)(8)(iv)(C).
9 Static wires and pole grounds are examples of grounding conductors that might not be capable of carrying fault current without failure. Grounds that can carry the maximum available fault current are not a concern, and employers need not consider such grounds a possible electric arc source.
Appendix F to § 1910.269—Work-Positioning Equipment Inspection Guidelines
I. Body Belts
Inspect body belts to ensure that:
A. The hardware has no cracks, nicks, distortion, or corrosion;
B. No loose or worn rivets are present;
C. The waist strap has no loose grommets;
D. The fastening straps are not 100-percent leather; and
E. No worn materials that could affect the safety of the user are present.
II. Positioning Straps
Inspect positioning straps to ensure that:
A. The warning center of the strap material is not exposed;
B. No cuts, burns, extra holes, or fraying of strap material is present;
C. Rivets are properly secured;
D. Straps are not 100-percent leather; and
E. Snaphooks do not have cracks, burns, or corrosion.
III. Climbers
Inspect pole and tree climbers to ensure that:
A. Gaffs are at least as long as the manufacturer's recommended minimums (generally 32 and 51 millimeters (1.25 and 2.0 inches) for pole and tree climbers, respectively, measured on the underside of the gaff);
B. Gaffs and leg irons are not fractured or cracked;
C. Stirrups and leg irons are free of excessive wear;
D. Gaffs are not loose;
E. Gaffs are free of deformation that could adversely affect use;
F. Gaffs are properly sharpened; and
G. There are no broken straps or buckles.
Appendix G to § 1910.269—Reference Documents
The references contained in this appendix provide information that can be helpful in understanding and complying with the requirements contained in § 1910.269. The national consensus standards referenced in this appendix contain detailed specifications that employers may follow in complying with the more performance-based requirements of § 1910.269. Except as specifically noted in § 1910.269, however, the Occupational Safety and Health Administration will not necessarily deem compliance with the national consensus standards to be compliance with the provisions of § 1910.269.
American National Standard for Vehicle-Mounted Elevating and Rotating Aerial Devices.
American National Standard Safety Requirements for Arboricultural Operations—Pruning, Trimming, Repairing, Maintaining, and Removing Trees, and Cutting Brush.
IEEE Guide on Terminology for Tools and Equipment to Be Used in Live Line Working.
Safety Standard for Conveyors and Related Equipment.
Standard Specification for Rubber Insulating Gloves.
Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies.
Standard Specification for Rubber Insulating Matting.
Standard Specification for Rubber Insulating Blankets.
Standard Specification for Rubber Insulating Covers.
Standard Specification for Rubber Insulating Line Hose.
Standard Specification for Rubber Insulating Sleeves.
Standard Specification for In-Service Care of Insulating Line Hose and Covers.
Standard Specification for In-Service Care of Insulating Blankets.
Standard Specification for In-Service Care of Insulating Gloves and Sleeves.
Standard Specification for Fiberglass-Reinforced Plastic (FRP) Rod and Tube Used in Live Line Tools.
Standard Test Methods and Specifications for Electrically Insulating Plastic Guard Equipment for Protection of Workers.
Standard Terminology Relating to Electrical Protective Equipment for Workers.
Standard Specifications for Temporary Protective Grounds to Be Used on De-energized Electric Power Lines and Equipment.
e1
Standard Specifications for Personal Climbing Equipment.
Standard Test Method for Acoustic Emission for Aerial Personnel Devices Without Supplemental Load Handling Attachments.
Standard Test Method for Determining Dielectric Strength of Dielectric Footwear.
Standard Specification for Dielectric Footwear.
Standard Guide for Visual Inspection of Electrical Protective Rubber Products.
Standard Test Method for Acoustic Emission Testing of Insulated and Non-Insulated Aerial Personnel Devices with Supplemental Load Handling Attachments.
Standard Specification for Insulated and Insulating Hand Tools.
Standard Performance Specification for Flame Resistant and Arc Rated Textile Materials for Wearing Apparel for Use by Electrical Workers Exposed to Momentary Electric Arc and Related Thermal Hazards.
Standard Specification for Structure-Mounted Insulating Work Platforms for Electrical Workers.
Standard Specification for Unused Polypropylene Rope with Special Electrical Properties.
Standard Specification for PVC Insulating Sheeting.
Standard Specification for High Voltage Detectors—Part 1 Capacitive Type to be Used for Voltages Exceeding 600 Volts AC.
ε
1
Standard Test Method for Acoustic Emission Testing of Insulated and Non-Insulated Digger Derricks.
Standard Specification for Clampstick Type Live Line Tools.
Standard Specification for Live Line and Measuring Telescoping Tools.
Standard Specification for Arc and Flame Resistant Rainwear.
Standard Test Method for Determining the Ignitability of Non-flame-Resistant Materials for Clothing by Electric Arc Exposure Method Using Mannequins.
Standard Test Method for Determining the Arc Rating of Materials for Clothing.
IEEE Standard Techniques for High-Voltage Testing
IEEE Standard Techniques for High-Voltage Testing.
IEEE Guide for Diagnostic Field Testing of Electric Power Apparatus—Part 1: Oil Filled Power Transformers, Regulators, and Reactors.
Guide for Safety in AC Substation Grounding.
The Authoritative Dictionary of IEEE Standards Terms Seventh Edition.
IEEE Guide for Maintenance Methods on Energized Power Lines.
IEEE Guide to the Installation of Overhead Transmission Line Conductors
IEEE Guide for Cleaning Insulators.
IEEE Guide for Protective Grounding of Power Lines.
IEEE Guide for In-Service Use, Care, Maintenance, and Testing of Conductive Clothing for Use on Voltages up to 765 kV AC and ±750 kV DC.
IEEE Standard for Fall Protection for Utility Work.
IEEE Guide for Performing Arc-Flash Hazard Calculations.
National Electrical Safety Code.
Standard for Electrical Safety in the Workplace.
[79 FR 20633, Apr. 11, 2014, as amended at 79 FR 56960, Sept. 24, 2014; 80 FR 60036, Oct. 5, 2015; 81 FR 83006, Nov. 18, 2016; 84 FR 68797, Dec. 17, 2019; 85 FR 8732, Feb. 18, 2020]
This section contains requirements for the control of grain dust fires and explosions, and certain other safety hazards associated with grain handling facilities. It applies in addition to all other relevant provisions of part 1910 (or part 1917 at marine terminals).
Choked leg means a condition of material buildup in the bucket elevator that results in the stoppage of material flow and bucket movement. A bucket elevator is not considered choked that has the up-leg partially or fully loaded and has the boot and discharge cleared allowing bucket movement.
Flat storage structure means a grain storage building or structure that will not empty completely by gravity, has an unrestricted ground level opening for entry, and must be entered to reclaim the residual grain using powered equipment or manual means.
Fugitive grain dust means combustible dust particles, emitted from the stock handling system, of such size as will pass through a U.S. Standard 40 mesh sieve (425 microns or less).
Grain elevator means a facility engaged in the receipt, handling, storage, and shipment of bulk raw agricultural commodities such as corn, wheat, oats, barley, sunflower seeds, and soybeans.
Hot work means work involving electric or gas welding, cutting, brazing, or similar flame producing operations.
Inside bucket elevator means a bucket elevator that has the boot and more than 20 percent of the total leg height (above grade or ground level) inside the grain elevator structure. Bucket elevators with leg casings that are inside (and pass through the roofs) of rail or truck dump sheds with the remainder of the leg outside of the grain elevator structure, are not considered inside bucket elevators.
Jogging means repeated starting and stopping of drive motors in an attempt to clear choked legs.
Lagging means a covering on drive pulleys used to increase the coefficient of friction between the pulley and the belt.
Permit means the written certification by the employer authorizing employees to perform identified work operations subject to specified precautions.
The employer shall develop and implement an emergency action plan meeting the requirements contained in 29 CFR 1910.38.
This paragraph applies to employee entry into bins, silos, tanks, and other grain storage structures. Exception: Entry through unrestricted ground level openings into flat storage structures in which there are no toxicity, flammability, oxygen-deficiency, or other atmospheric hazards is covered by paragraph (h) of this section. For the purposes of this paragraph (g), the term “grain” includes raw and processed grain and grain products in facilities within the scope of paragraph (b)(1) of this section.
For the purposes of this paragraph (h), the term “grain” means raw and processed grain and grain products in facilities within the scope of paragraph (b)(1) of this section.
Receiving-pit feed openings, such as truck or railcar receiving-pits, shall be covered by grates. The width of openings in the grates shall be a maximum of 2 1/2 inches (6.35 cm).
The employer shall equip grain stream processing equipment (such as hammer mills, grinders, and pulverizers) with an effective means of removing ferrous material from the incoming grain stream.
This subpart addresses electrical safety requirements that are necessary for the practical safeguarding of employees in their workplaces and is divided into four major divisions as follows:
These regulations are contained in §§ 1910.302 through 1910.330. Sections 1910.302 through 1910.308 contain design safety standards for electric utilization systems. Included in this category are all electric equipment and installations used to provide electric power and light for employee workplaces. Sections 1910.309 through 1910.330 are reserved for possible future design safety standards for other electrical systems.
These regulations will be contained in §§ 1910.331 through 1910.360.
These regulations will be contained in §§ 1910.361 through 1910.380.
These regulations will be contained in §§ 1910.381 through 1910.398.
Definitions applicable to each division are contained in § 1910.399.
[46 FR 4056, Jan. 16, 1981; 46 FR 40185, Aug. 7, 1981]
Sections 1910.302 through 1910.308 contain design safety standards for electric utilization systems.
The provisions of §§ 1910.302 through 1910.308 cover electrical installations and utilization equipment installed or used within or on buildings, structures, and other premises, including:
The provisions of §§ 1910.302 through 1910.308 do not cover:
The following requirements apply to all electrical installations and utilization equipment, regardless of when they were designed or installed:
§ 1910.303(b)—Examination, installation, and use of equipment
§ 1910.303(c)(3)—Electrical connections—Splices
§ 1910.303(d)—Arcing parts
§ 1910.303(e)—Marking
§ 1910.303(f), except (f)(4) and (f)(5)—Disconnecting means and circuits
§ 1910.303(g)(2)—600 volts or less—Guarding of live parts
§ 1910.304(a)(3)—Use of grounding terminals and devices
§ 1910.304(f)(1)(i), (f)(1)(iv), and (f)(1)(v)—Overcurrent protection—600 volts, nominal, or less
§ 1910.304(g)(1)(ii), (g)(1)(iii), (g)(1)(iv), and (g)(1)(v)—Grounding—Systems to be grounded
§ 1910.304(g)(4)—Grounding—Grounding connections
§ 1910.304(g)(5)—Grounding—Grounding path
§ 1910.304(g)(6)(iv)(A) through (g)(6)(iv)(D), and (g)(6)(vi)—Grounding—Supports, enclosures, and equipment to be grounded
§ 1910.304(g)(7)—Grounding—Nonelectrical equipment
§ 1910.304(g)(8)(i)—Grounding—Methods of grounding fixed equipment
§ 1910.305(g)(1)—Flexible cords and cables—Use of flexible cords and cables
§ 1910.305(g)(2)(ii) and (g)(2)(iii)—Flexible cords and cables—Identification, splices, and terminations
§ 1910.307, except as specified in § 1910.307(b)—Hazardous (classified) locations
§ 1910.303(h)(4)—Over 600 volts, nominal—Entrance and access to work space
§ 1910.304(f)(1)(vii) and (f)(1)(viii)—Overcurrent protection—600 volts, nominal, or less
§ 1910.304(g)(9)(i)—Grounding—Grounding of systems and circuits of 1000 volts and over (high voltage)
§ 1910.305(j)(6)(ii)(D)—Equipment for general use—Capacitors
§ 1910.306(c)(9)—Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts, and stairway chair lifts—Interconnection between multicar controllers
§ 1910.306(i)—Electrically driven or controlled irrigation machines
§ 1910.306(j)(5)—Swimming pools, fountains, and similar installations—Fountains
§ 1910.308(a)(1)(ii)—Systems over 600 volts, nominal—Aboveground wiring methods
§ 1910.308(c)(2)—Class 1, Class 2, and Class 3 remote control, signaling, and power-limited circuits—Marking
§ 1910.308(d)—Fire alarm systems
§ 1910.303(f)(4)—Disconnecting means and circuits—Capable of accepting a lock
§ 1910.303(f)(5)—Disconnecting means and circuits—Marking for series combination ratings
§ 1910.303(g)(1)(iv) and (g)(1)(vii)—600 Volts, nominal, or less—Space about electric equipment
§ 1910.303(h)(5)(vi)—Over 600 volts, nominal—Working space and guarding
§ 1910.304(b)(1)—Branch circuits—Identification of multiwire branch circuits
§ 1910.304(b)(3)(i)—Branch circuits—Ground-fault circuit interrupter protection for personnel
§ 1910.304(f)(2)(i)(A), (f)(2)(i)(B) (but not the introductory text to § 1910.304(f)(2)(i)), and (f)(2)(iv)(A)—Overcurrent protection—Feeders and branch circuits over 600 volts, nominal
§ 1910.305(c)(3)(ii)—Switches—Connection of switches
§ 1910.305(c)(5)—Switches—Grounding
§ 1910.306(a)(1)(ii)—Electric signs and outline lighting—Disconnecting means
§ 1910.306(c)(4)—Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts, and stairway chair lifts—Operation
§ 1910.306(c)(5)—Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts, and stairway chair lifts—Location
§ 1910.306(c)(6)—Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts, and stairway chair lifts—Identification and signs
§ 1910.306(c)(7)—Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts, and stairway chair lifts—Single-car and multicar installations
§ 1910.306(j)(1)(iii)—Swimming pools, fountains, and similar installations—Receptacles
§ 1910.306(k)—Carnivals, circuses, fairs, and similar events
§ 1910.308(a)(5)(v) and (a)(5)(vi)(B)—Systems over 600 volts, nominal—Interrupting and isolating devices
§ 1910.308(a)(7)(vi)—Systems over 600 volts, nominal—Tunnel installations
§ 1910.308(b)(3)—Emergency power systems—Signs
§ 1910.308(c)(3)—Class 1, Class 2, and Class 3 remote control, signaling, and power-limited circuits—Separation from conductors of other circuits
§ 1910.308(f)—Solar photovoltaic systems
The conductors and equipment required or permitted by this subpart shall be acceptable only if approved, as defined in § 1910.399.
Electric equipment shall be free from recognized hazards that are likely to cause death or serious physical harm to employees. Safety of equipment shall be determined using the following considerations:
Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.
Completed wiring installations shall be free from short circuits and from grounds other than those required or permitted by this subpart.
Equipment intended to interrupt current at fault levels shall have an interrupting rating sufficient for the nominal circuit voltage and the current that is available at the line terminals of the equipment. Equipment intended to interrupt current at other than fault levels shall have an interrupting rating at nominal circuit voltage sufficient for the current that must be interrupted.
The overcurrent protective devices, the total impedance, the component short-circuit current ratings, and other characteristics of the circuit to be protected shall be selected and coordinated to permit the circuit protective devices used to clear a fault to do so without the occurrence of extensive damage to the electrical components of the circuit. This fault shall be assumed to be either between two or more of the circuit conductors, or between any circuit conductor and the grounding conductor or enclosing metal raceway.
Unless identified for use in the operating environment, no conductors or equipment shall be located in damp or wet locations; where exposed to gases, fumes, vapors, liquids, or other agents that have a deteriorating effect on the conductors or equipment; or where exposed to excessive temperatures.
Electric equipment shall be installed in a neat and workmanlike manner.
Because of different characteristics of dissimilar metals:
Parts of electric equipment that in ordinary operation produce arcs, sparks, flames, or molten metal shall be enclosed or separated and isolated from all combustible material.
Electric equipment may not be used unless the following markings have been placed on the equipment:
The marking shall be of sufficient durability to withstand the environment involved.
Each disconnecting means required by this subpart for motors and appliances shall be legibly marked to indicate its purpose, unless located and arranged so the purpose is evident.
The markings required by paragraphs (f)(1) and (f)(2) of this section shall be of sufficient durability to withstand the environment involved.
Disconnecting means required by this subpart shall be capable of being locked in the open position.
Sufficient access and working space shall be provided and maintained about all electric equipment to permit ready and safe operation and maintenance of such equipment.
| Nominal voltage to ground | Minimum clear distance for condition 2 3 | |||||
|---|---|---|---|---|---|---|
| Condition A | Condition B | Condition C | ||||
| m | ft | m | ft | m | ft | |
| 0-150 | 1 0.9 | 1 3.0 | 1 0.9 | 1 3.0 | 0.9 | 3.0 |
| 151-600 | 1 0.9 | 1 3.0 | 1.0 | 3.5 | 1.2 | 4.0 |
| Notes to Table S-1: | ||||||
| 1. Minimum clear distances may be 0.7 m (2.5 ft) for installations built before April 16, 1981. | ||||||
| 2. Conditions A, B, and C are as follows: | ||||||
| Condition A—Exposed live parts on one side and no live or grounded parts on the other side of the working space, or exposed live parts on both sides effectively guarded by suitable wood or other insulating material. Insulated wire or insulated busbars operating at not over 300 volts are not considered live parts. | ||||||
| Condition B—Exposed live parts on one side and grounded parts on the other side. | ||||||
| Condition C—Exposed live parts on both sides of the work space (not guarded as provided in Condition A) with the operator between. | ||||||
| 3. Working space is not required in back of assemblies such as dead-front switchboards or motor control centers where there are no renewable or adjustable parts (such as fuses or switches) on the back and where all connections are accessible from locations other than the back. Where rear access is required to work on deenergized parts on the back of enclosed equipment, a minimum working space of 762 mm (30 in.) horizontally shall be provided. |
Conductors and equipment used on circuits exceeding 600 volts, nominal, shall comply with all applicable provisions of the paragraphs (a) through (g) of this section and with the following provisions, which supplement or modify the preceding requirements. However, paragraphs (h)(2), (h)(3), and (h)(4) of this section do not apply to the equipment on the supply side of the service point.
Sufficient space shall be provided and maintained about electric equipment to permit ready and safe operation and maintenance of such equipment. Where energized parts are exposed, the minimum clear work space may not be less than 1.98 m (6.5 ft) high (measured vertically from the floor or platform) or less than 914 mm (3.0 ft) wide (measured parallel to the equipment). The depth shall be as required in paragraph (h)(5)(i) of this section. In all cases, the work space shall be adequate to permit at least a 90-degree opening of doors or hinged panels.
“DANGER—HIGH VOLTAGE—KEEP OUT.”
| Nominal voltage to ground | Minimum clear distance for condition 2 3 | |||||
|---|---|---|---|---|---|---|
| Condition A | Condition B | Condition C | ||||
| m | ft | m | ft | m | ft | |
| 601-2500 V | 0.9 | 3.0 | 1.2 | 4.0 | 1.5 | 5.0 |
| 2501-9000 V | 1.2 | 4.0 | 1.5 | 5.0 | 1.8 | 6.0 |
| 9001 V-25 kV | 1.5 | 5.0 | 1.8 | 6.0 | 2.8 | 9.0 |
| Over 25-75 kV 1 | 1.8 | 6.0 | 2.5 | 8.0 | 3.0 | 10.0 |
| Above 75 kV 1 | 2.5 | 8.0 | 3.0 | 10.0 | 3.7 | 12.0 |
| Notes to Table S-2: | ||||||
| 1 Minimum depth of clear working space in front of electric equipment with a nominal voltage to ground above 25,000 volts may be the same as that for 25,000 volts under Conditions A, B, and C for installations built before April 16, 1981. | ||||||
| 2 Conditions A, B, and C are as follows: | ||||||
| Condition A—Exposed live parts on one side and no live or grounded parts on the other side of the working space, or exposed live parts on both sides effectively guarded by suitable wood or other insulating material. Insulated wire or insulated busbars operating at not over 300 volts are not considered live parts. | ||||||
| Condition B—Exposed live parts on one side and grounded parts on the other side. Concrete, brick, and tile walls are considered as grounded surfaces. | ||||||
| Condition C—Exposed live parts on both sides of the work space (not guarded as provided in Condition A) with the operator between. | ||||||
| 3 Working space is not required in back of equipment such as dead-front switchboards or control assemblies that has no renewable or adjustable parts (such as fuses or switches) on the back and where all connections are accessible from locations other than the back. Where rear access is required to work on the deenergized parts on the back of enclosed equipment, a minimum working space 762 mm (30 in.) horizontally shall be provided. |
| Nominal voltage between phases | Elevation | |
|---|---|---|
| m | ft | |
| 601-7500 V | 1 2.8 | 1 9.0. |
| 7501 V-35 kV | 2.8 | 9.0. |
| Over 35 kV | 2.8 + 9.5 mm/kV over 35 kV | 9.0 + 0.37 in./kV over 35 kV. |
| 1 The minimum elevation may be 2.6 m (8.5 ft) for installations built before August 13, 2007. The minimum elevation may be 2.4 m (8.0 ft) for installations built before April 16, 1981, if the nominal voltage between phases is in the range of 601-6600 volts. |
[46 FR 4056, Jan. 16, 1981, as amended at 73 FR 64205, Oct. 29, 2008]
No grounded conductor may be attached to any terminal or lead so as to reverse designated polarity.
A grounding terminal or grounding-type device on a receptacle, cord connector, or attachment plug may not be used for purposes other than grounding.
Where more than one nominal voltage system exists in a building containing multiwire branch circuits, each ungrounded conductor of a multiwire branch circuit, where accessible, shall be identified by phase and system. The means of identification shall be permanently posted at each branch-circuit panelboard.
Outlet devices shall have an ampere rating not less than the load to be served and shall comply with the following provisions:
A receptacle outlet shall be installed wherever flexible cords with attachment plugs are used. Where flexible cords are permitted to be permanently connected, receptacles may be omitted.
| Circuit rating (amperes) | Receptacle rating (amperes) | Maximum load (amperes) |
|---|---|---|
| 15 or 20 | 15 | 12 |
| 20 | 20 | 16 |
| 30 | 30 | 24 |
| Circuit rating (amperes) | Receptacle rating (amperes) |
|---|---|
| 15 | Not over 15. |
| 20 | 15 or 20. |
| 30 | 30. |
| 40 | 40 or 50. |
| 50 | 50. |
Conductors on poles shall have a separation of not less than 305 mm (1.0 ft) where not placed on racks or brackets. Conductors supported on poles shall provide a horizontal climbing space not less than the following:
Open conductors, open multiconductor cables, and service-drop conductors of not over 600 volts, nominal, shall conform to the minimum clearances specified in Table S-6.
| Distance | Installations built before August 13, 2007 | Installations built on or after August 13, 2007 | ||
|---|---|---|---|---|
| Maximum voltage | Conditions | Voltage to ground | Conditions | |
| 3.05 m (10.0 ft) | <600 V | Above finished grade or sidewalks, or from any platform or projection from which they might be reached. (If these areas are accessible to other than pedestrian traffic, then one of the other conditions applies) | <150 V | Above finished grade or sidewalks, or from any platform or projection from which they might be reached. (If these areas are accessible to other than pedestrian traffic, then one of the other conditions applies.) |
| 3.66 m (12.0 ft) | <600 V | Over areas, other than public streets, alleys, roads, and driveways, subject to vehicular traffic other than truck traffic | <300 V | Over residential property and driveways. Over commercial areas subject to pedestrian traffic or to vehicular traffic other than truck traffic. (This category includes conditions covered under the 3.05-m (10.0-ft) category where the voltage exceeds 150 V.) |
| 4.57 m (15.0 ft) | <600 V | Over areas, other than public streets, alleys, roads, and driveways, subject to truck traffic | 301 to 600 V | Over residential property and driveways. Over commercial areas subject to pedestrian traffic or to vehicular traffic other than truck traffic. (This category includes conditions covered under the 3.05-m (10.0-ft) category where the voltage exceeds 300 V.) |
| 5.49 m (18.0 ft) | <600 V | Over public streets, alleys, roads, and driveways | <600 V | Over public streets, alleys, roads, and driveways. Over commercial areas subject to truck traffic. Other land traversed by vehicles, including land used for cultivating or grazing and forests and orchards. |
Overhead spans of open conductors and open multiconductor cables shall have a vertical clearance of not less than 2.44 m (8.0 ft) above the roof surface. The vertical clearance above the roof level shall be maintained for a distance not less than 914 mm (3.0 ft) in all directions from the edge of the roof.
Lamps for outdoor lighting shall be located below all energized conductors, transformers, or other electric equipment, unless such equipment is controlled by a disconnecting means that can be locked in the open position, or unless adequate clearances or other safeguards are provided for relamping operations.
Paragraphs (g)(1) through (g)(9) of this section contain grounding requirements for systems, circuits, and equipment.
Systems that supply premises wiring shall be grounded as follows:
circuits of less than 50 volts shall be grounded if they are installed as overhead conductors outside of buildings or if they are supplied by transformers and the transformer primary supply system is ungrounded or exceeds 150 volts to ground;
systems of 50 volts to 1000 volts shall be grounded under any of the following conditions, unless exempted by paragraph (g)(1)(v) of this section:
systems of 50 volts to 1000 volts are not required to be grounded under any of the following conditions:
The conductor to be grounded for ac premises wiring systems required to be grounded by paragraph (g)(1) of this section shall be as follows:
The path to ground from circuits, equipment, and enclosures shall be permanent, continuous, and effective.
hedge clippers, lawn mowers, snow blowers, and wet scrubbers;
( 8 Portable hand lamps.
The metal parts of the following nonelectrical equipment shall be grounded: frames and tracks of electrically operated cranes and hoists; frames of nonelectrically driven elevator cars to which electric conductors are attached; hand-operated metal shifting ropes or cables of electric elevators; and metal partitions, grill work, and similar metal enclosures around equipment of over 750 volts between conductors.
[46 FR 4056, Jan. 16, 1981, as amended at 73 FR 64205, Oct. 29, 2008]
The provisions of this section do not apply to conductors that are an integral part of factory-assembled equipment.
Except as specifically modified in this paragraph, all other requirements of this subpart for permanent wiring shall also apply to temporary wiring installations.
8 shall be rigidly supported on noncombustible, nonabsorbent insulating materials and may not contact any other objects. Supports shall be installed as follows:
Single-throw knife switches shall be so placed that gravity will not tend to close them. Single-throw knife switches approved for use in the inverted position shall be provided with a locking device that will ensure that the blades remain in the open position when so set.
Double-throw knife switches may be mounted so that the throw will be either vertical or horizontal. However, if the throw is vertical, a locking device shall be provided to ensure that the blades remain in the open position when so set.
Snap switches mounted in boxes shall have faceplates installed so as to completely cover the opening and seat against the finished surface.
Snap switches, including dimmer switches, shall be effectively grounded and shall provide a means to ground metal faceplates, whether or not a metal faceplate is installed. However, if no grounding means exists within the snap-switch enclosure, or where the wiring method does not include or provide an equipment ground, a snap switch without a grounding connection is permitted for replacement purposes only. Such snap switches shall be provided with a faceplate of nonconducting, noncombustible material if they are located within reach of conducting floors or other conducting surfaces.
Switchboards that have any exposed live parts shall be located in permanently dry locations and shall be accessible only to qualified persons.
Panelboards shall be mounted in cabinets, cutout boxes, or enclosures designed for the purpose and shall be dead front. However, panelboards other than the dead front externally-operable type are permitted where accessible only to qualified persons.
Exposed blades of knife switches mounted in switchboards or panelboards shall be dead when open.
All conductors used for general wiring shall be insulated unless otherwise permitted in this subpart.
The conductor insulation shall be of a type that is approved for the voltage, operating temperature, and location of use.
Insulated conductors shall be distinguishable by appropriate color or other suitable means as being grounded conductors, ungrounded conductors, or equipment grounding conductors.
Multiconductor portable cable for use in supplying power to portable or mobile equipment at over 600 volts, nominal, shall consist of No. 8 or larger conductors employing flexible stranding. However, the minimum size of the insulated ground-check conductor of Type G-GC cables shall be No. 10.
Cables operated at over 2,000 volts shall be shielded for the purpose of confining the voltage stresses to the insulation.
Grounding conductors shall be provided.
All shields shall be grounded.
The minimum bending radii for portable cables during installation and handling in service shall be adequate to prevent damage to the cable.
Connectors used to connect lengths of cable in a run shall be of a type that lock firmly together. Provisions shall be made to prevent opening or closing these connectors while energized. Strain relief shall be provided at connections and terminations.
Portable cables may not be operated with splices unless the splices are of the permanent molded, vulcanized, or other approved type.
Termination enclosures shall be suitably marked with a high voltage hazard warning, and terminations shall be accessible only to authorized and qualified employees.
Fixture wires shall be approved for the voltage, temperature, and location of use. A fixture wire which is used as a grounded conductor shall be identified.
Fixture wires may be used only:
Fixture wires may not be used as branch-circuit conductors except as permitted for Class 1 power limited circuits and for fire alarm circuits.
This paragraph applies to motors, motor circuits, and controllers.
Provisions shall be made for sufficient diffusion and ventilation of gases from storage batteries to prevent the accumulation of explosive mixtures.
This paragraph applies to the installation of electric equipment and wiring used in connection with cranes, monorail hoists, hoists, and all runways.
A limit switch or other device shall be provided to prevent the load block from passing the safe upper limit of travel of any hoisting mechanism.
The dimension of the working space in the direction of access to live parts that may require examination, adjustment, servicing, or maintenance while alive shall be a minimum of 762 mm (2.5 ft). Where controls are enclosed in cabinets, the doors shall either open at least 90 degrees or be removable.
Elevators, dumbwaiters, escalators, moving walks, wheelchair lifts, and stairway chair lifts shall have a single means for disconnecting all ungrounded main power supply conductors for each unit.
Control panels not located in the same space as the drive machine shall be located in cabinets with doors or panels capable of being locked closed.
The disconnecting means shall be an enclosed externally operable fused motor circuit switch or circuit breaker capable of being locked in the open position. The disconnecting means shall be a listed device.
No provision may be made to open or close this disconnecting means from any other part of the premises. If sprinklers are installed in hoistways, machine rooms, or machinery spaces, the disconnecting means may automatically open the power supply to the affected elevators prior to the application of water. No provision may be made to close this disconnecting means automatically (that is, power may only be restored by manual means).
The disconnecting means shall be located where it is readily accessible to qualified persons.
On single-car and multicar installations, equipment receiving electrical power from more than one source shall be provided with a disconnecting means for each source of electrical power. The disconnecting means shall be within sight of the equipment served.
A warning sign worded as required in paragraph (c)(8) of this section shall be mounted on or next to the disconnecting means where interconnections between controllers are necessary for the operation of the system on multicar installations that remain energized from a source other than the one disconnected.
Motor controllers may be located outside the spaces otherwise required by paragraph (c) of this section, provided they are in enclosures with doors or removable panels capable of being locked closed and the disconnecting means is located adjacent to or is an integral part of the motor controller. Motor controller enclosures for escalators or moving walks may be located in the balustrade on the side located away from the moving steps or moving treadway. If the disconnecting means is an integral part of the motor controller, it shall be operable without opening the enclosure.
A disconnecting means shall be provided in the supply circuit for each arc welder that is not equipped with a disconnect mounted as an integral part of the welder. The disconnecting means shall be a switch or circuit breaker, and its rating may not be less than that necessary to accommodate overcurrent protection.
A switch or circuit breaker shall be provided by which each resistance welder and its control equipment can be disconnected from the supply circuit. The ampere rating of this disconnecting means may not be less than the supply conductor ampacity. The supply circuit switch may be used as the welder disconnecting means where the circuit supplies only one welder.
A means shall be provided to disconnect power to all electronic equipment in an information technology equipment room. There shall also be a similar means to disconnect the power to all dedicated heating, ventilating, and air-conditioning (HVAC) systems serving the room and to cause all required fire/smoke dampers to close.
The control for these disconnecting means shall be grouped and identified and shall be readily accessible at the principal exit doors. A single means to control both the electronic equipment and HVAC system is permitted.
Integrated electrical systems covered by § 1910.308(g) need not have the disconnecting means required by paragraph (e)(1) of this section.
This paragraph applies to X-ray equipment.
The following requirements apply to industrial and commercial laboratory equipment.
This paragraph applies to induction and dielectric heating equipment and accessories for industrial and scientific applications, but not for medical or dental applications or for appliances.
This paragraph applies to the installation of the electrical components and accessory equipment of electrolytic cells, electrolytic cell lines, and process power supply for the production of aluminum, cadmium, chlorine, copper, fluorine, hydrogen peroxide, magnesium, sodium, sodium chlorate, and zinc. Cells used as a source of electric energy and for electroplating processes and cells used for production of hydrogen are not covered by this paragraph.
Installations covered by paragraph (h) of this section shall comply with all applicable provisions of this subpart, except as follows:
If more than one dc cell line process power supply serves the same cell line, a disconnecting means shall be provided on the cell line circuit side of each power supply to disconnect it from the cell line circuit. Removable links or removable conductors may be used as the disconnecting means.
systems supplying fixed and portable electric equipment within the cell line working zone; and
Auxiliary nonelectrical connections such as air hoses, water hoses, and the like, to an electrolytic cell, its attachments, or auxiliary equipment may not have continuous conductive reinforcing wire, armor, braids, or the like. Hoses shall be of a nonconductive material.
If an irrigation machine has a stationary point, a grounding electrode system shall be connected to the machine at the stationary point for lightning protection.
Flexible cords used with the following equipment may not exceed 0.9 m (3 ft) in length and shall have a copper equipment grounding conductor with a grounding-type attachment plug:
All electric equipment, including power supply cords, operating at more than 15 volts and used with fountains shall be protected by ground-fault circuit interrupters.
Electric equipment and wiring methods in or on rides, concessions, or other units shall be provided with mechanical protection where such equipment or wiring methods are subject to physical damage.
Electrical wiring for temporary lighting, where installed inside of tents and concessions, shall be securely installed, and, where subject to physical damage, shall be provided with mechanical protection. All temporary lamps for general illumination shall be protected from accidental breakage by a suitable fixture or lampholder with a guard.
Employers may only use portable distribution and termination boxes that meet the following requirements:
This section covers the requirements for electric equipment and wiring in locations that are classified depending on the properties of the flammable vapors, liquids or gases, or combustible dusts or fibers that may be present therein and the likelihood that a flammable or combustible concentration or quantity is present. Hazardous (classified) locations may be found in occupancies such as, but not limited to, the following: aircraft hangars, gasoline dispensing and service stations, bulk storage plants for gasoline or other volatile flammable liquids, paint-finishing process plants, health care facilities, agricultural or other facilities where excessive combustible dusts may be present, marinas, boat yards, and petroleum and chemical processing plants. Each room, section or area shall be considered individually in determining its classification.
All applicable requirements in this subpart apply to hazardous (classified) locations unless modified by provisions of this section.
In Class I locations, an installation must be classified as using the division classification system meeting paragraphs (c), (d), (e), and (f) of this section or using the zone classification system meeting paragraph (g) of this section. In Class II and Class III locations, an installation must be classified using the division classification system meeting paragraphs (c), (d), (e), and (f) of this section.
All areas designated as hazardous (classified) locations under the Class and Zone system and areas designated under the Class and Division system established after August 13, 2007 shall be properly documented. This documentation shall be available to those authorized to design, install, inspect, maintain, or operate electric equipment at the location.
Equipment, wiring methods, and installations of equipment in hazardous (classified) locations shall be intrinsically safe, approved for the hazardous (classified) location, or safe for the hazardous (classified) location. Requirements for each of these options are as follows:
Equipment and associated wiring approved as intrinsically safe is permitted in any hazardous (classified) location for which it is approved;
Equipment that is safe for the location shall be of a type and design that the employer demonstrates will provide protection from the hazards arising from the combustibility and flammability of vapors, liquids, gases, dusts, or fibers involved.
All conduits shall be threaded and shall be made wrench-tight. Where it is impractical to make a threaded joint tight, a bonding jumper shall be utilized.
Equipment that has been approved for a Division 1 location may be installed in a Division 2 location of the same class and group. General-purpose equipment or equipment in general-purpose enclosures may be installed in Division 2 locations if the employer can demonstrate that the equipment does not constitute a source of ignition under normal operating conditions.
The following are acceptable protection techniques for electric and electronic equipment in hazardous (classified) locations.
This protection technique is permitted for equipment in the Class I, Division 1 and 2 locations for which it is approved.
This protection technique is permitted for equipment in the Class II, Division 1 and 2 locations for which it is approved.
This protection technique is permitted for equipment in the Class II, Division 2 and Class III locations for which it is approved.
This protection technique is permitted for equipment in any hazardous (classified) location for which it is approved.
This protection technique is permitted for equipment in Class I, Division 2; Class II, Division 2; or Class III, Division 1or 2 locations.
This protection technique is permitted for equipment in Class I, Division 2; Class II, Division 2; or Class III, Division 1 or 2 locations.
This protection technique is permitted for equipment in Class I, Division 2; Class II, Division 2; or Class III, Division 1 or 2 locations.
This protection technique is permitted for current-interrupting contacts in Class I, Division 2 locations as described in the Subpart.
This protection technique is permitted for equipment in Class I, Division 2; Class II, Division 2; and Class III, Division 1 or 2 locations.
Any other protection technique that meets paragraph (c) of this section is acceptable in any hazardous (classified) location.
Employers may use the zone classification system as an alternative to the division classification system for electric and electronic equipment and wiring for all voltage in Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases, vapors, or liquids.
One or more of the following protection techniques shall be used for electric and electronic equipment in hazardous (classified) locations classified under the zone classification system.
Paragraph (g) of this section requires equipment construction and installation that will ensure safe performance under conditions of proper use and maintenance.
The braid on open runs of braid-covered insulated conductors shall be flame retardant or shall have a flame-retardant saturant applied after installation. This treated braid covering shall be stripped back a safe distance at conductor terminals, according to the operating voltage.
Where cable conductors emerge from a metal sheath and where protection against moisture or physical damage is necessary, the insulation of the conductors shall be protected by a cable sheath terminating device.
This paragraph applies to installation and use of high-voltage power distribution and utilization equipment that is portable or mobile, such as substations, trailers, cars, mobile shovels, draglines, hoists, drills, dredges, compressors, pumps, conveyors, and underground excavators.
This paragraph applies to circuits, systems, and equipment intended to supply power for illumination and special loads in the event of failure of the normal supply.
Emergency circuit wiring shall be kept entirely independent of all other wiring and equipment and may not enter the same raceway, cable, box, or cabinet or other wiring except either where common circuit elements suitable for the purpose are required, or for transferring power from the normal to the emergency source.
Emergency illumination shall include all required means of egress lighting, illuminated exit signs, and all other lights necessary to provide illumination. Where emergency lighting is necessary, the system shall be so arranged that the failure of any individual lighting element, such as the burning out of a light bulb, cannot leave any space in total darkness.
Class 1, Class 2, and Class 3 remote control, signaling, or power-limited circuits are characterized by their usage and electrical power limitation that differentiates them from light and power circuits. These circuits are classified in accordance with their respective voltage and power limitations as summarized in paragraphs (c)(1)(i) through (c)(1)(iii) of this section.
A Class 2 or Class 3 power supply unit shall be durably marked where plainly visible to indicate the class of supply and its electrical rating.
Cables and conductors of Class 2 and Class 3 circuits may not be placed in any cable, cable tray, compartment, enclosure, manhole, outlet box, device box, raceway, or similar fitting with conductors of electric light, power, Class 1, nonpower-limited fire alarm circuits, and medium power network-powered broadband communications cables unless a barrier or other equivalent form of protection against contact is employed.
Fire alarm circuits shall be classified either as nonpower limited or power limited.
The power sources for use with fire alarm circuits shall be either power limited or nonpower limited as follows:
Fire alarm circuits shall be identified at terminal and junction locations in a manner that will prevent unintentional interference with the signaling circuit during testing and servicing. Power-limited fire alarm circuits shall be durably marked as such where plainly visible at terminations.
This paragraph applies to central-station-connected and non-central-station-connected telephone circuits, radio and television receiving and transmitting equipment, including community antenna television and radio distribution systems, telegraph, district messenger, and outside wiring for fire and burglar alarm, and similar central station systems. These installations need not comply with the provisions of § 1910.303 through § 1910.308(d), except for §§ 1910.304(c)(1) and 1910.307.
Outdoor metal structures supporting antennas, as well as self-supporting antennas such as vertical rods or dipole structures, shall be located as far away from overhead conductors of electric light and power circuits of over 150 volts to ground as necessary to prevent the antenna or structure from falling into or making accidental contact with such circuits.
This paragraph covers solar photovoltaic systems that can be interactive with other electric power production sources or can stand alone with or without electrical energy storage such as batteries. These systems may have ac or dc output for utilization.
Photovoltaic source circuits and photovoltaic output circuits may not be contained in the same raceway, cable tray, cable, outlet box, junction box, or similar fitting as feeders or branch circuits of other systems, unless the conductors of the different systems are separated by a partition or are connected together.
Means shall be provided to disconnect all current-carrying conductors of a photovoltaic power source from all other conductors in a building or other structure. Where a circuit grounding connection is not designed to be automatically interrupted as part of the ground-fault protection system, a switch or circuit breaker used as disconnecting means may not have a pole in the grounded conductor.
Paragraph (g) of this section covers integrated electrical systems, other than unit equipment, in which orderly shutdown is necessary to ensure safe operation. An integrated electrical system as used in this section shall be a unitized segment of an industrial wiring system where all of the following conditions are met:
Overcurrent devices that are critical to integrated electrical systems need not be readily accessible to employees as required by § 1910.304(f)(1)(iv) if they are located with mounting heights to ensure security from operation by nonqualified persons.
The provisions of §§ 1910.331 through 1910.335 cover electrical safety-related work practices for both qualified persons (those who have training in avoiding the electrical hazards of working on or near exposed energized parts) and unqualified persons (those with little or no such training) working on, near, or with the following installations:
Installations of electric conductors and equipment within or on buildings or other structures, and on other premises such as yards, carnival, parking, and other lots, and industrial substations;
Installations of conductors that connect to the supply of electricity; and
Installations of other outside conductors on the premises.
Installations of optical fiber cable where such installations are made along with electric conductors.
The provisions of §§ 1910.331 through 1910.335 also cover:
The provisions of §§ 1910.331 through 1910.335 do not apply to work performed by qualified persons on or directly associated with the following installations:
Installations of communication equipment to the extent that the work is covered under § 1910.268.
Installations in ships, watercraft, railway rolling stock, aircraft, or automotive vehicles other than mobile homes and recreational vehicles.
Installations of railways for generation, transformation, transmission, or distribution of power used exclusively for operation of rolling stock or installations of railways used exclusively for signaling and communication purposes.
[55 FR 32016, Aug. 6, 1990, as amended at 59 FR 4476, Jan. 31, 1994; 79 FR 20692, Apr. 11, 2014; 80 FR 60039, Oct. 5, 2015]
The training requirements contained in this section apply to employees who face a risk of electric shock that is not reduced to a safe level by the electrical installation requirements of §§ 1910.303 through 1910.308.
Employees shall be trained in and familiar with the safety-related work practices required by §§ 1910.331 through 1910.335 that pertain to their respective job assignments.
Employees who are covered by paragraph (a) of this section but who are not qualified persons shall also be trained in and familiar with any electrically related safety practices not specifically addressed by §§ 1910.331 through 1910.335 but which are necessary for their safety.
Qualified persons (i.e., those permitted to work on or near exposed energized parts) shall, at a minimum, be trained in and familiar with the following:
The training required by this section shall be of the classroom or on-the-job type. The degree of training provided shall be determined by the risk to the employee.
| Occupation |
|---|
| Blue collar supervisors. 1 |
| Electrical and electronic engineers. 1 |
| Electrical and electronic equipment assemblers. 1 |
| Electrical and electronic technicians. 1 |
| Electricians. |
| Industrial machine operators. 1 |
| Material handling equipment operators. 1 |
| Mechanics and repairers. 1 |
| Painters. 1 |
| Riggers and roustabouts. 1 |
| Stationary engineers. 1 |
| Welders. |
| 1 Workers in these groups do not need to be trained if their work or the work of those they supervise does not bring them or the employees they supervise close enough to exposed parts of electric circuits operating at 50 volts or more to ground for a hazard to exist. |
[55 FR 32016, Aug. 6, 1990]
Safety-related work practices shall be employed to prevent electric shock or other injuries resulting from either direct or indirect electrical contacts, when work is performed near or on equipment or circuits which are or may be energized. The specific safety-related work practices shall be consistent with the nature and extent of the associated electrical hazards.
Live parts to which an employee may be exposed shall be deenergized before the employee works on or near them, unless the employer can demonstrate that deenergizing introduces additional or increased hazards or is infeasible due to equipment design or operational limitations. Live parts that operate at less than 50 volts to ground need not be deenergized if there will be no increased exposure to electrical burns or to explosion due to electric arcs.
If the exposed live parts are not deenergized (i.e., for reasons of increased or additional hazards or infeasibility), other safety-related work practices shall be used to protect employees who may be exposed to the electrical hazards involved. Such work practices shall protect employees against contact with energized circuit parts directly with any part of their body or indirectly through some other conductive object. The work practices that are used shall be suitable for the conditions under which the work is to be performed and for the voltage level of the exposed electric conductors or circuit parts. Specific work practice requirements are detailed in paragraph (c) of this section.
This paragraph applies to work on exposed deenergized parts or near enough to them to expose the employee to any electrical hazard they present. Conductors and parts of electric equipment that have been deenergized but have not been locked out or tagged in accordance with paragraph (b) of this section shall be treated as energized parts, and paragraph (c) of this section applies to work on or near them.
While any employee is exposed to contact with parts of fixed electric equipment or circuits which have been deenergized, the circuits energizing the parts shall be locked out or tagged or both in accordance with the requirements of this paragraph. The requirements shall be followed in the order in which they are presented (i.e., paragraph (b)(2)(i) first, then paragraph (b)(2)(ii), etc.).
The employer shall maintain a written copy of the procedures outlined in paragraph (b)(2) and shall make it available for inspection by employees and by the Assistant Secretary of Labor and his or her authorized representatives.
The requirements of this paragraph shall be met before any circuits or equipment can be considered and worked as deenergized.
These requirements shall be met, in the order given, before circuits or equipment are reenergized, even temporarily.
This paragraph applies to work performed on exposed live parts (involving either direct contact or contact by means of tools or materials) or near enough to them for employees to be exposed to any hazard they present.
Only qualified persons may work on electric circuit parts or equipment that have not been deenergized under the procedures of paragraph (b) of this section. Such persons shall be capable of working safely on energized circuits and shall be familiar with the proper use of special precautionary techniques, personal protective equipment, insulating and shielding materials, and insulated tools.
If work is to be performed near overhead lines, the lines shall be deenergized and grounded, or other protective measures shall be provided before work is started. If the lines are to be deenergized, arrangements shall be made with the person or organization that operates or controls the electric circuits involved to deenergize and ground them. If protective measures, such as guarding, isolating, or insulating are provided, these precautions shall prevent employees from contacting such lines directly with any part of their body or indirectly through conductive materials, tools, or equipment.
When a qualified person is working in the vicinity of overhead lines, whether in an elevated position or on the ground, the person may not approach or take any conductive object without an approved insulating handle closer to exposed energized parts than shown in Table S-5 unless:
| Voltage range (phase to phase) | Minimum approach distance |
|---|---|
| 300V and less | Avoid contact. |
| Over 300V, not over 750V | 1 ft. 0 in. (30.5 cm). |
| Over 750V, not over 2kV | l ft. 6 in. (46 cm). |
| Over 2kV, not over 15kV | 2 ft. 0 in. (61 cm). |
| Over 15kV, not over 37kV | 3 ft. 0 in. (91 cm). |
| Over 37kV, not over 87.5kV | 3 ft. 6 in. (107 cm). |
| Over 87.5kV, not over 121kV | 4 ft. 0 in. (122 cm). |
| Over 121kV, not over 140kV | 4 ft. 6 in. (137 cm). |
When an employee works in a confined or enclosed space (such as a manhole or vault) that contains exposed energized parts, the employer shall provide, and the employee shall use, protective shields, protective barriers, or insulating materials as necessary to avoid inadvertent contact with these parts. Doors, hinged panels, and the like shall be secured to prevent their swinging into an employee and causing the employee to contact exposed energized parts.
Conductive materials and equipment that are in contact with any part of an employee's body shall be handled in a manner that will prevent them from contacting exposed energized conductors or circuit parts. If an employee must handle long dimensional conductive objects (such as ducts and pipes) in areas with exposed live parts, the employer shall institute work practices (such as the use of insulation, guarding, and material handling techniques) which will minimize the hazard.
Portable ladders shall have nonconductive siderails if they are used where the employee or the ladder could contact exposed energized parts.
Conductive articles of jewelry and clothing (such as watch bands, bracelets, rings, key chains, necklaces, metalized aprons, cloth with conductive thread, or metal headgear) may not be worn if they might contact exposed energized parts. However, such articles may be worn if they are rendered nonconductive by covering, wrapping, or other insulating means.
Where live parts present an electrical contact hazard, employees may not perform housekeeping duties at such close distances to the parts that there is a possibility of contact, unless adequate safeguards (such as insulating equipment or barriers) are provided. Electrically conductive cleaning materials (including conductive solids such as steel wool, metalized cloth, and silicon carbide, as well as conductive liquid solutions) may not be used in proximity to energized parts unless procedures are followed which will prevent electrical contact.
Only a qualified person following the requirements of paragraph (c) of this section may defeat an electrical safety interlock, and then only temporarily while he or she is working on the equipment. The interlock system shall be returned to its operable condition when this work is completed.
[55 FR 32016, Aug. 6, 1990; 55 FR 46053, Nov. 1, 1990, as amended at 59 FR 4476, Jan. 31, 1994]
This paragraph applies to the use of cord- and plug-connected equipment, including flexible cord sets (extension cords).
Portable equipment shall be handled in a manner which will not cause damage. Flexible electric cords connected to equipment may not be used for raising or lowering the equipment. Flexible cords may not be fastened with staples or otherwise hung in such a fashion as could damage the outer jacket or insulation.
Portable electric equipment and flexible cords used in highly conductive work locations (such as those inundated with water or other conductive liquids), or in job locations where employees are likely to contact water or conductive liquids, shall be approved for those locations.
Load rated switches, circuit breakers, or other devices specifically designed as disconnecting means shall be used for the opening, reversing, or closing of circuits under load conditions. Cable connectors not of the load-break type, fuses, terminal lugs, and cable splice connections may not be used for such purposes, except in an emergency.
After a circuit is deenergized by a circuit protective device, the circuit may not be manually reenergized until it has been determined that the equipment and circuit can be safely energized. The repetitive manual reclosing of circuit breakers or reenergizing circuits through replaced fuses is prohibited.
Overcurrent protection of circuits and conductors may not be modified, even on a temporary basis, beyond that allowed by § 1910.304(e), the installation safety requirements for overcurrent protection.
Only qualified persons may perform testing work on electric circuits or equipment.
Test instruments and equipment and all associated test leads, cables, power cords, probes, and connectors shall be visually inspected for external defects and damage before the equipment is used. If there is a defect or evidence of damage that might expose an employee to injury, the defective or damaged item shall be removed from service, and no employee may use it until repairs and tests necessary to render the equipment safe have been made.
Test instruments and equipment and their accessories shall be rated for the circuits and equipment to which they will be connected and shall be designed for the environment in which they will be used.
Where flammable materials are present only occasionally, electric equipment capable of igniting them shall not be used, unless measures are taken to prevent hazardous conditions from developing. Such materials include, but are not limited to: flammable gases, vapors, or liquids; combustible dust; and ignitible fibers or flyings.
[55 FR 32019, Aug. 6, 1990]
The following alerting techniques shall be used to warn and protect employees from hazards which could cause injury due to electric shock, burns, or failure of electric equipment parts:
Safety signs, safety symbols, or accident prevention tags shall be used where necessary to warn employees about electrical hazards which may endanger them, as required by § 1910.145.
Barricades shall be used in conjunction with safety signs where it is necessary to prevent or limit employee access to work areas exposing employees to uninsulated energized conductors or circuit parts. Conductive barricades may not be used where they might cause an electrical contact hazard.
If signs and barricades do not provide sufficient warning and protection from electrical hazards, an attendant shall be stationed to warn and protect employees.
[55 FR 32020, Aug. 6, 1990]
Acceptable. An installation or equipment is acceptable to the Assistant Secretary of Labor, and approved within the meaning of this subpart S:
Accepted. An installation is “accepted” if it has been inspected and found by a nationally recognized testing laboratory to conform to specified plans or to procedures of applicable codes.
Accessible. (As applied to wiring methods.) Capable of being removed or exposed without damaging the building structure or finish, or not permanently closed in by the structure or finish of the building. (See “concealed” and “exposed.”)
Accessible. (As applied to equipment.) Admitting close approach; not guarded by locked doors, elevation, or other effective means. (See “Readily accessible.”)
Ampacity. The current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Appliances. Utilization equipment, generally other than industrial, normally built in standardized sizes or types, that is installed or connected as a unit to perform one or more functions.
Approved. Acceptable to the authority enforcing this subpart. The authority enforcing this subpart is the Assistant Secretary of Labor for Occupational Safety and Health. The definition of “acceptable” indicates what is acceptable to the Assistant Secretary of Labor, and therefore approved within the meaning of this subpart.
Armored cable (Type AC). A fabricated assembly of insulated conductors in a flexible metallic enclosure.
Askarel. A generic term for a group of nonflammable synthetic chlorinated hydrocarbons used as electrical insulating media. Askarels of various compositional types are used. Under arcing conditions, the gases produced, while consisting predominantly of noncombustible hydrogen chloride, can include varying amounts of combustible gases depending upon the askarel type.
Attachment plug (Plug cap)(Cap). A device that, by insertion in a receptacle, establishes a connection between the conductors of the attached flexible cord and the conductors connected permanently to the receptacle.
Automatic. Self-acting, operating by its own mechanism when actuated by some impersonal influence, as, for example, a change in current strength, pressure, temperature, or mechanical configuration.
Bare conductor. See Conductor.
Barrier. A physical obstruction that is intended to prevent contact with equipment or live parts or to prevent unauthorized access to a work area.
Bathroom. An area including a basin with one or more of the following: a toilet, a tub, or a shower.
Bonding (Bonded). The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity and the capacity to conduct safely any current likely to be imposed.
Bonding jumper. A conductor that assures the necessary electrical conductivity between metal parts required to be electrically connected.
Branch circuit. The circuit conductors between the final overcurrent device protecting the circuit and the outlets.
Building. A structure that stands alone or is cut off from adjoining structures by fire walls with all openings therein protected by approved fire doors.
Cabinet. An enclosure designed either for surface or flush mounting, and provided with a frame, mat, or trim in which a swinging door or doors are or can be hung.
Cable tray system. A unit or assembly of units or sections and associated fittings forming a rigid structural system used to securely fasten or support cables and raceways. Cable tray systems include ladders, troughs, channels, solid bottom trays, and other similar structures.
Cablebus. An assembly of insulated conductors with fittings and conductor terminations in a completely enclosed, ventilated, protective metal housing.
Cell line. An assembly of electrically interconnected electrolytic cells supplied by a source of direct current power.
Cell line attachments and auxiliary equipment. Cell line attachments and auxiliary equipment include, but are not limited to, auxiliary tanks, process piping, ductwork, structural supports, exposed cell line conductors, conduits and other raceways, pumps, positioning equipment, and cell cutout or bypass electrical devices. Auxiliary equipment also includes tools, welding machines, crucibles, and other portable equipment used for operation and maintenance within the electrolytic cell line working zone. In the cell line working zone, auxiliary equipment includes the exposed conductive surfaces of ungrounded cranes and crane-mounted cell-servicing equipment.
Center pivot irrigation machine. A multi-motored irrigation machine that revolves around a central pivot and employs alignment switches or similar devices to control individual motors.
Certified. Equipment is “certified” if it bears a label, tag, or other record of certification that the equipment:
Circuit breaker. A device designed to open and close a circuit by nonautomatic means and to open the circuit automatically on a predetermined overcurrent without damage to itself when properly applied within its rating.
Class I locations. Class I locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures. Class I locations include the following:
Class II locations. Class II locations are those that are hazardous because of the presence of combustible dust. Class II locations include the following:
Class III locations. Class III locations are those that are hazardous because of the presence of easily ignitable fibers or flyings, but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitable mixtures. Class III locations include the following:
Collector ring. An assembly of slip rings for transferring electric energy from a stationary to a rotating member.
Competent Person. One who is capable of identifying existing and predictable hazards in the surroundings or working conditions that are unsanitary, hazardous, or dangerous to employees and who has authorization to take prompt corrective measures to eliminate them.
Concealed. Rendered inaccessible by the structure or finish of the building. Wires in concealed raceways are considered concealed, even though they may become accessible by withdrawing them. (See Accessible. (As applied to wiring methods.))
Conductor —
A conductor having no covering or electrical insulation whatsoever.
A conductor encased within material of composition or thickness that is not recognized by this subpart as electrical insulation.
A conductor encased within material of composition and thickness that is recognized by this subpart as electrical insulation.
Conduit body. A separate portion of a conduit or tubing system that provides access through one or more removable covers to the interior of the system at a junction of two or more sections of the system or at a terminal point of the system. Boxes such as FS and FD or larger cast or sheet metal boxes are not classified as conduit bodies.
Controller. A device or group of devices that serves to govern, in some predetermined manner, the electric power delivered to the apparatus to which it is connected.
Covered conductor. See Conductor.
Cutout. (Over 600 volts, nominal.) An assembly of a fuse support with either a fuseholder, fuse carrier, or disconnecting blade. The fuseholder or fuse carrier may include a conducting element (fuse link), or may act as the disconnecting blade by the inclusion of a nonfusible member.
Cutout box. An enclosure designed for surface mounting and having swinging doors or covers secured directly to and telescoping with the walls of the box proper. (See Cabinet.)
Damp location. See Location.
Dead front. Without live parts exposed to a person on the operating side of the equipment
Deenergized. Free from any electrical connection to a source of potential difference and from electrical charge; not having a potential different from that of the earth.
Device. A unit of an electrical system that is intended to carry but not utilize electric energy.
Dielectric heating. The heating of a nominally insulating material due to its own dielectric losses when the material is placed in a varying electric field.
Disconnecting means. A device, or group of devices, or other means by which the conductors of a circuit can be disconnected from their source of supply.
Disconnecting (or Isolating) switch. (Over 600 volts, nominal.) A mechanical switching device used for isolating a circuit or equipment from a source of power.
Electrolytic cell line working zone. The cell line working zone is the space envelope wherein operation or maintenance is normally performed on or in the vicinity of exposed energized surfaces of electrolytic cell lines or their attachments.
Electrolytic cells. A tank or vat in which electrochemical reactions are caused by applying energy for the purpose of refining or producing usable materials.
Enclosed. Surrounded by a case, housing, fence, or walls that will prevent persons from accidentally contacting energized parts.
Enclosure. The case or housing of apparatus, or the fence or walls surrounding an installation to prevent personnel from accidentally contacting energized parts, or to protect the equipment from physical damage.
Energized. Electrically connected to a source of potential difference.
Equipment. A general term including material, fittings, devices, appliances, fixtures, apparatus, and the like, used as a part of, or in connection with, an electrical installation.
Equipment grounding conductor. See Grounding conductor, equipment.
Explosion-proof apparatus. Apparatus enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that it will not ignite a surrounding flammable atmosphere.
Exposed. (As applied to live parts.) Capable of being inadvertently touched or approached nearer than a safe distance by a person. It is applied to parts not suitably guarded, isolated, or insulated. (See Accessible and Concealed.)
Exposed. (As applied to wiring methods.) On or attached to the surface, or behind panels designed to allow access. (See Accessible. (As applied to wiring methods.))
Exposed. (For the purposes of § 1910.308(e).) Where the circuit is in such a position that in case of failure of supports or insulation, contact with another circuit may result.
Externally operable. Capable of being operated without exposing the operator to contact with live parts.
Feeder. All circuit conductors between the service equipment, the source of a separate derived system, or other power supply source and the final branch-circuit overcurrent device.
Fitting. An accessory such as a locknut, bushing, or other part of a wiring system that is intended primarily to perform a mechanical rather than an electrical function.
Fountain. Fountains, ornamental pools, display pools, and reflection pools.
Fuse. (Over 600 volts, nominal.) An overcurrent protective device with a circuit opening fusible part that is heated and severed by the passage of overcurrent through it. A fuse comprises all the parts that form a unit capable of performing the prescribed functions. It may or may not be the complete device necessary to connect it into an electrical circuit.
Ground. A conducting connection, whether intentional or accidental, between an electric circuit or equipment and the earth, or to some conducting body that serves in place of the earth.
Grounded. Connected to the earth or to some conducting body that serves in place of the earth.
Grounded, effectively. Intentionally connected to earth through a ground connection or connections of sufficiently low impedance and having sufficient current-carrying capacity to prevent the buildup of voltages that may result in undue hazards to connected equipment or to persons.
Grounded conductor. A system or circuit conductor that is intentionally grounded.
Grounding conductor. A conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode or electrodes.
Grounding conductor, equipment. The conductor used to connect the noncurrent-carrying metal parts of equipment, raceways, and other enclosures to the system grounded conductor, the grounding electrode conductor, or both, at the service equipment or at the source of a separately derived system.
Grounding electrode conductor. The conductor used to connect the grounding electrode to the equipment grounding conductor, to the grounded conductor, or to both, of the circuits at the service equipment or at the source of a separately derived system.
Ground-fault circuit-interrupter. A device intended for the protection of personnel that functions to deenergize a circuit or a portion of a circuit within an established period of time when a current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.
Guarded. Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers, casings, barriers, rails, screens, mats, or platforms to remove the likelihood of approach to a point of danger or contact by persons or objects.
Health care facilities. Buildings or portions of buildings in which medical, dental, psychiatric, nursing, obstetrical, or surgical care are provided.
Heating equipment. For the purposes of § 1910.306(g), the term “heating equipment” includes any equipment used for heating purposes if heat is generated by induction or dielectric methods.
Hoistway. Any shaftway, hatchway, well hole, or other vertical opening or space that is designed for the operation of an elevator or dumbwaiter.
Identified (as applied to equipment). Approved as suitable for the specific purpose, function, use, environment, or application, where described in a particular requirement.
Induction heating. The heating of a nominally conductive material due to its own I 2 R losses when the material is placed in a varying electromagnetic field.
Insulated. Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current.
Insulated conductor. See Conductor, Insulated.
Interrupter switch. (Over 600 volts, nominal.) A switch capable of making, carrying, and interrupting specified currents.
Irrigation Machine. An electrically driven or controlled machine, with one or more motors, not hand portable, and used primarily to transport and distribute water for agricultural purposes.
Isolated. (As applied to location.) Not readily accessible to persons unless special means for access are used.
Isolated power system. A system comprising an isolating transformer or its equivalent, a line isolation monitor, and its ungrounded circuit conductors.
Labeled. Equipment is “labeled” if there is attached to it a label, symbol, or other identifying mark of a nationally recognized testing laboratory:
Lighting outlet. An outlet intended for the direct connection of a lampholder, a lighting fixture, or a pendant cord terminating in a lampholder.
Listed. Equipment is “listed” if it is of a kind mentioned in a list that:
Live parts. Energized conductive components.
Location —
Partially protected locations under canopies, marquees, roofed open porches, and like locations, and interior locations subject to moderate degrees of moisture, such as some basements, some barns, and some cold-storage warehouses.
A location not normally subject to dampness or wetness. A location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building under construction.
Installations underground or in concrete slabs or masonry in direct contact with the earth, and locations subject to saturation with water or other liquids, such as vehicle-washing areas, and locations unprotected and exposed to weather.
Medium voltage cable (Type MV). A single or multiconductor solid dielectric insulated cable rated 2001 volts or higher.
Metal-clad cable (Type MC). A factory assembly of one or more insulated circuit conductors with or without optical fiber members enclosed in an armor of interlocking metal tape, or a smooth or corrugated metallic sheath.
Mineral-insulated metal-sheathed cable (Type MI). Type MI, mineral-insulated metal-sheathed, cable is a factory assembly of one or more conductors insulated with a highly compressed refractory mineral insulation and enclosed in a liquidtight and gastight continuous copper or alloy steel sheath.
Mobile X-ray. X-ray equipment mounted on a permanent base with wheels or casters or both for moving while completely assembled.
Motor control center. An assembly of one or more enclosed sections having a common power bus and principally containing motor control units.
Nonmetallic-sheathed cable (Types NM, NMC, and NMS). A factory assembly of two or more insulated conductors having an outer sheath of moisture resistant, flame-retardant, nonmetallic material.
Oil (filled) cutout. (Over 600 volts, nominal.) A cutout in which all or part of the fuse support and its fuse link or disconnecting blade are mounted in oil with complete immersion of the contacts and the fusible portion of the conducting element (fuse link), so that arc interruption by severing of the fuse link or by opening of the contacts will occur under oil.
Open wiring on insulators. Open wiring on insulators is an exposed wiring method using cleats, knobs, tubes, and flexible tubing for the protection and support of single insulated conductors run in or on buildings, and not concealed by the building structure.
Outlet. A point on the wiring system at which current is taken to supply utilization equipment.
Outline lighting. An arrangement of incandescent lamps or electric discharge lighting to outline or call attention to certain features, such as the shape of a building or the decoration of a window.
Overcurrent. Any current in excess of the rated current of equipment or the ampacity of a conductor. It may result from overload, short circuit, or ground fault.
Overhaul means to perform a major replacement, modification, repair, or rehabilitation similar to that involved when a new building or facility is built, a new wing is added, or an entire floor is renovated.
Overload. Operation of equipment in excess of normal, full-load rating, or of a conductor in excess of rated ampacity that, when it persists for a sufficient length of time, would cause damage or dangerous overheating. A fault, such as a short circuit or ground fault, is not an overload. (See Overcurrent.)
Panelboard. A single panel or group of panel units designed for assembly in the form of a single panel; including buses, automatic overcurrent devices, and with or without switches for the control of light, heat, or power circuits; designed to be placed in a cabinet or cutout box placed in or against a wall or partition and accessible only from the front. (See Switchboard.)
Permanently installed decorative fountains and reflection pools. Pools that are constructed in the ground, on the ground, or in a building in such a manner that the fountain or pool cannot be readily disassembled for storage, whether or not served by electrical circuits of any nature. These units are primarily constructed for their aesthetic value and are not intended for swimming or wading.
Permanently installed swimming, wading, and therapeutic pools. Pools that are constructed in the ground or partially in the ground, and all other capable of holding water in a depth greater than 1.07 m (42 in.). The definition also applies to all pools installed inside of a building, regardless of water depth, whether or not served by electric circuits of any nature.
Portable X-ray. X-ray equipment designed to be hand-carried.
Power and control tray cable (Type TC). A factory assembly of two or more insulated conductors, with or without associated bare or covered grounding conductors under a nonmetallic sheath, approved for installation in cable trays, in raceways, or where supported by a messenger wire.
Power fuse. (Over 600 volts, nominal.) See Fuse.
Power-limited tray cable (Type PLTC). A factory assembly of two or more insulated conductors under a nonmetallic jacket.
Power outlet. An enclosed assembly, which may include receptacles, circuit breakers, fuseholders, fused switches, buses, and watt-hour meter mounting means, that is intended to supply and control power to mobile homes, recreational vehicles, or boats or to serve as a means for distributing power needed to operate mobile or temporarily installed equipment.
Premises wiring. (Premises wiring system.) The interior and exterior wiring, including power, lighting, control, and signal circuit wiring together with all of their associated hardware, fittings, and wiring devices, both permanently and temporarily installed, that extends from the service point of utility conductors or source of power (such as a battery, a solar photovoltaic system, or a generator, transformer, or converter) to the outlets. Such wiring does not include wiring internal to appliances, fixtures, motors, controllers, motor control centers, and similar equipment.
Qualified person. One who has received training in and has demonstrated skills and knowledge in the construction and operation of electric equipment and installations and the hazards involved.
Raceway. An enclosed channel of metal or nonmetallic materials designed expressly for holding wires, cables, or busbars, with additional functions as permitted in this standard. Raceways include, but are not limited to, rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, liquidtight flexible conduit, flexible metallic tubing, flexible metal conduit, electrical metallic tubing, electrical nonmetallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface raceways, wireways, and busways.
Readily accessible. Capable of being reached quickly for operation, renewal, or inspections, so that those needing ready access do not have to climb over or remove obstacles or to resort to portable ladders, chairs, etc. (See Accessible.)
Receptacle. A receptacle is a contact device installed at the outlet for the connection of an attachment plug. A single receptacle is a single contact device with no other contact device on the same yoke. A multiple receptacle is two or more contact devices on the same yoke.
Receptacle outlet. An outlet where one or more receptacles are installed.
Remote-control circuit. Any electric circuit that controls any other circuit through a relay or an equivalent device.
Sealable equipment. Equipment enclosed in a case or cabinet that is provided with a means of sealing or locking so that live parts cannot be made accessible without opening the enclosure. The equipment may or may not be operable without opening the enclosure.
Separately derived system. A premises wiring system whose power is derived from a battery, a solar photovoltaic system, or from a generator, transformer, or converter windings, and that has no direct electrical connection, including a solidly connected grounded circuit conductor, to supply conductors originating in another system.
Service. The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served.
Service cable. Service conductors made up in the form of a cable.
Service conductors. The conductors from the service point to the service disconnecting means.
Service drop. The overhead service conductors from the last pole or other aerial support to and including the splices, if any, connecting to the service-entrance conductors at the building or other structure.
Service-entrance cable. A single conductor or multiconductor assembly provided with or without an overall covering, primarily used for services, and is of the following types:
Type SE, having a flame-retardant, moisture resistant covering; and
Type USE, identified for underground use, having a moisture-resistant covering, but not required to have a flame-retardant covering. Cabled, single-conductor, Type USE constructions recognized for underground use may have a bare copper conductor cabled with the assembly. Type USE single, parallel, or cable conductor assemblies recognized for underground use may have a bare copper concentric conductor applied. These constructions do not require an outer overall covering.
Service-entrance conductors, overhead system. The service conductors between the terminals of the service equipment and a point usually outside the building, clear of building walls, where joined by tap or splice to the service drop.
Service entrance conductors, underground system. The service conductors between the terminals of the service equipment and the point of connection to the service lateral.
Service equipment. The necessary equipment, usually consisting of one or more circuit breakers or switches and fuses, and their accessories, connected to the load end of service conductors to a building or other structure, or an otherwise designated area, and intended to constitute the main control and cutoff of the supply.
Service point. The point of connection between the facilities of the serving utility and the premises wiring.
Shielded nonmetallic-sheathed cable (Type SNM). A factory assembly of two or more insulated conductors in an extruded core of moisture-resistant, flame-resistant nonmetallic material, covered with an overlapping spiral metal tape and wire shield and jacketed with an extruded moisture-, flame-, oil-, corrosion-, fungus-, and sunlight-resistant nonmetallic material.
Show window. Any window used or designed to be used for the display of goods or advertising material, whether it is fully or partly enclosed or entirely open at the rear and whether or not it has a platform raised higher than the street floor level.
Signaling circuit. Any electric circuit that energizes signaling equipment.
Storable swimming or wading pool. A pool that is constructed on or above the ground and is capable of holding water to a maximum depth of 1.07 m (42 in.), or a pool with nonmetallic, molded polymeric walls or inflatable fabric walls regardless of dimension.
Switchboard. A large single panel, frame, or assembly of panels on which are mounted, on the face or back, or both, switches, overcurrent and other protective devices, buses, and (usually) instruments. Switchboards are generally accessible from the rear as well as from the front and are not intended to be installed in cabinets. (See Panelboard.)
Switch —
A switch intended for use in general distribution and branch circuits. It is rated in amperes, and it is capable of interrupting its rated current at its rated voltage.
A form of general-use switch constructed so that it can be installed in device boxes or on box covers, or otherwise used in conjunction with wiring systems recognized by this subpart.
A switch intended for isolating an electric circuit from the source of power. It has no interrupting rating, and it is intended to be operated only after the circuit has been opened by some other means.
A switch, rated in horsepower, capable of interrupting the maximum operating overload current of a motor of the same horsepower rating as the switch at the rated voltage.
Switching devices. (Over 600 volts, nominal.) Devices designed to close and open one or more electric circuits. Included in this category are circuit breakers, cutouts, disconnecting (or isolating) switches, disconnecting means, interrupter switches, and oil (filled) cutouts.
Transportable X-ray. X-ray equipment installed in a vehicle or that may readily be disassembled for transport in a vehicle.
Utilization equipment. Equipment that utilizes electric energy for electronic, electromechanical, chemical, heating, lighting, or similar purposes.
Ventilated. Provided with a means to permit circulation of air sufficient to remove an excess of heat, fumes, or vapors.
Volatile flammable liquid. A flammable liquid having a flash point below 38 °C (100 °F), or a flammable liquid whose temperature is above its flash point, or a Class II combustible liquid having a vapor pressure not exceeding 276 kPa (40 psia) at 38 °C (100 °F) and whose temperature is above its flash point.
Voltage (of a circuit). The greatest root-mean-square (rms) (effective) difference of potential between any two conductors of the circuit concerned.
Voltage, nominal. A nominal value assigned to a circuit or system for the purpose of conveniently designating its voltage class (as 120/240 volts, 480Y/277 volts, 600 volts). The actual voltage at which a circuit operates can vary from the nominal within a range that permits satisfactory operation of equipment.
Voltage to ground. For grounded circuits, the voltage between the given conductor and that point or conductor of the circuit that is grounded; for ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit.
Watertight. So constructed that moisture will not enter the enclosure.
Weatherproof. So constructed or protected that exposure to the weather will not interfere with successful operation. Rainproof, raintight, or watertight equipment can fulfill the requirements for weatherproof where varying weather conditions other than wetness, such as snow, ice, dust, or temperature extremes, are not a factor.
Wireways. Sheet-metal troughs with hinged or removable covers for housing and protecting electric wires and cable and in which conductors are laid in place after the wireway has been installed as a complete system.
[72 FR 7215, Feb. 14, 2007, as amended at 79 FR 20692, Apr. 11, 2014]
The references contained in this appendix provide nonmandatory information that can be helpful in understanding and complying with subpart S of this Part. However, compliance with these standards is not a substitute for compliance with subpart S of this Part.
ANSI/API RP 500-1998 (2002) Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I Division 1 and Division 2.
ANSI/API RP 505-1997 (2002) Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1 and Zone 2.
ANSI/ASME A17.1-2004 Safety Code for Elevators and Escalators.
ANSI/ASME B30.2-2005 Overhead and Gantry Cranes (Top Running Bridge, Single or Multiple Girder, Top Running Trolley Hoist).
ANSI/ASME B30.3-2004 Construction Tower Cranes.
ANSI/ASME B30.4-2003 Portal, Tower, and Pedestal Cranes.
ANSI/ASME B30.5-2004 Mobile And Locomotive Cranes.
ANSI/ASME B30.6-2003 Derricks.
ANSI/ASME B30.7-2001 Base Mounted Drum Hoists.
ANSI/ASME B30.8-2004 Floating Cranes And Floating Derricks.
ANSI/ASME B30.11-2004 Monorails And Underhung Cranes.
ANSI/ASME B30.12-2001 Handling Loads Suspended from Rotorcraft.
ANSI/ASME B30.13-2003 Storage/Retrieval (S/R) Machines and Associated Equipment.
ANSI/ASME B30.16-2003 Overhead Hoists (Underhung).
ANSI/ASME B30.22-2005 Articulating Boom Cranes.
ANSI/ASSE Z244.1-2003 Control of Hazardous Energy Lockout/Tagout and Alternative Methods.
ANSI/ASSE Z490.1-2001 Criteria for Accepted Practices in Safety, Health, and Environmental Training.
ANSI/IEEE C2-2002 National Electrical Safety Code.
ANSI K61.1-1999 Safety Requirements for the Storage and Handling of Anhydrous Ammonia.
ANSI/UL 913-2003 Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Division 1, Hazardous (Classified) Locations.
ASTM D3176-1989 (2002) Standard Practice for Ultimate Analysis of Coal and Coke.
ASTM D3180-1989 (2002) Standard Practice for Calculating Coal and Coke Analyses from As-Determined to Different Bases.
NFPA 20-2003 Standard for the Installation of Stationary Pumps for Fire Protection.
NFPA 30-2003 Flammable and Combustible Liquids Code.
NFPA 32-2004 Standard for Drycleaning Plants.
NFPA 33-2003 Standard for Spray Application Using Flammable or Combustible Materials.
NFPA 34-2003 Standard for Dipping and Coating Processes Using Flammable or Combustible Liquids.
NFPA 35-2005 Standard for the Manufacture of Organic Coatings.
NFPA 36-2004 Standard for Solvent Extraction Plants.
NFPA 40-2001 Standard for the Storage and Handling of Cellulose Nitrate Film.
NFPA 58-2004 Liquefied Petroleum Gas Code.
NFPA 59-2004 Utility LP-Gas Plant Code.
NFPA 70-2002 National Electrical Code. (See also NFPA 70-2005.)
NFPA 70E-2000 Standard for Electrical Safety Requirements for Employee Workplaces. (See also NFPA 70E-2004.)
NFPA 77-2000 Recommended Practice on Static Electricity.
NFPA 80-1999 Standard for Fire Doors and Fire Windows.
NFPA 88A-2002 Standard for Parking Structures.
NFPA 91-2004 Standard for Exhaust Systems for Air Conveying of Vapors, Gases, Mists, and Noncombustible Particulate Solids.
NFPA 101-2006 Life Safety Code.
NFPA 496-2003 Standard for Purged and Pressurized Enclosures for Electrical Equipment.
NFPA 497-2004 Recommended Practice for the Classification of Flammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas.
NFPA 505-2006 Fire Safety Standard for Powered Industrial Trucks Including Type Designations, Areas of Use, Conversions, Maintenance, and Operation.
NFPA 820-2003 Standard for Fire Protection in Wastewater Treatment and Collection Facilities.
NMAB 353-1-1979 Matrix of Combustion-Relevant Properties and Classification of Gases, Vapors, and Selected Solids.
NMAB 353-2-1979 Test Equipment for Use in Determining Classifications of Combustible Dusts.
NMAB 353-3-1980 Classification of Combustible Dust in Accordance with the National Electrical Code.
[72 FR 7221, Feb. 14, 2007]
An employer may deviate from the requirements of this standard to the extent necessary to prevent or minimize a situation which is likely to cause death, serious physical harm, or major environmental damage, provided that the employer:
The employer shall be responsible for compliance with:
[42 FR 37668, July 22, 1977, as amended at 47 FR 53365, Nov. 26, 1982; 58 FR 35310, June 30, 1993; 69 FR 7363, Feb. 17, 2004]
As used in this standard, the listed terms are defined as follows:
Acfm: Actual cubic feet per minute.
ASME Code or equivalent: ASME (American Society of Mechanical Engineers) Boiler and Pressure Vessel Code, Section VIII, or an equivalent code which the employer can demonstrate to be equally effective.
ATA: Atmosphere absolute.
Bell: An enclosed compartment, pressurized (closed bell) or unpressurized (open bell), which allows the diver to be transported to and from the underwater work area and which may be used as a temporary refuge during diving operations.
Bottom time: The total elasped time measured in minutes from the time when the diver leaves the surface in descent to the time that the diver begins ascent.
Bursting pressure: The pressure at which a pressure containment device would fail structurally.
Cylinder: A pressure vessel for the storage of gases.
Decompression chamber: A pressure vessel for human occupancy such as a surface decompression chamber, closed bell, or deep diving system used to decompress divers and to treat decompression sickness.
Decompression sickness: A condition with a variety of symptoms which may result from gas or bubbles in the tissues of divers after pressure reduction.
Decompression table: A profile or set of profiles of depth-time relationships for ascent rates and breathing mixtures to be followed after a specific depth-time exposure or exposures.
Dive-guiding operations means leading groups of sports divers, who use an open-circuit, semi-closed-circuit, or closed-circuit self-contained underwater breathing apparatus, to local undersea diving locations for recreational purposes.
Dive location: A surface or vessel from which a diving operation is conducted.
Dive-location reserve breathing gas: A supply system of air or mixed-gas (as appropriate) at the dive location which is independent of the primary supply system and sufficient to support divers during the planned decompression.
Dive team: Divers and support employees involved in a diving operation, including the designated person-in-charge.
Diver: An employee working in water using underwater apparatus which supplies compressed breathing gas at the ambient pressure.
Diver-carried reserve breathing gas: A diver-carried supply of air or mixed gas (as appropriate) sufficient under standard operating conditions to allow the diver to reach the surface, or another source of breathing gas, or to be reached by a standby diver.
Diving mode: A type of diving requiring specific equipment, procedures and techniques (SCUBA, surface-supplied air, or mixed gas).
Fsw: Feet of seawater (or equivalent static pressure head).
Heavy gear: Diver-worn deep-sea dress including helmet, breastplate, dry suit, and weighted shoes.
Hyperbaric conditions: Pressure conditions in excess of surface pressure.
Inwater stage: A suspended underwater platform which supports a diver in the water.
Liveboating: The practice of supporting a surfaced-supplied air or mixed gas diver from a vessel which is underway.
Mixed-gas diving: A diving mode in which the diver is supplied in the water with a breathing gas other than air.
No-decompression limits: The depth-time limits of the “no-decompression limits and repetitive dive group designation table for no-decompression air dives”, U.S. Navy Diving Manual or equivalent limits which the employer can demonstrate to be equally effective.
Psi(g): Pounds per square inch (gauge).
Recreational diving instruction means training diving students in the use of recreational diving procedures and the safe operation of diving equipment, including an open-circuit, semi-closed-circuit, or closed-circuit self-contained underwater breathing apparatus, during dives.
Scientific diving means diving performed solely as a necessary part of a scientific, research, or educational activity by employees whose sole purpose for diving is to perform scientific research tasks. Scientific diving does not include performing any tasks usually associated with commercial diving such as: Placing or removing heavy objects underwater; inspection of pipelines and similar objects; construction; demolition; cutting or welding; or the use of explosives.
SCUBA diving: A diving mode independent of surface supply in which the diver uses open circuit self-contained underwater breathing apparatus.
Standby diver: A diver at the dive location available to assist a diver in the water.
Surface-supplied air diving: A diving mode in which the diver in the water is supplied from the dive location with compressed air for breathing.
Treatment table: A depth-time and breathing gas profile designed to treat decompression sickness.
Umbilical: The composite hose bundle between a dive location and a diver or bell, or between a diver and a bell, which supplies the diver or bell with breathing gas, communications, power, or heat as appropriate to the diving mode or conditions, and includes a safety line between the diver and the dive location.
Volume tank: A pressure vessel connected to the outlet of a compressor and used as an air reservoir.
Working pressure: The maximum pressure to which a pressure containment device may be exposed under standard operating conditions.
[42 FR 37668, July 22, 1977, as amended at 47 FR 53365, Nov. 26, 1982; 69 FR 7363, Feb. 17, 2004]
and
The employer shall develop and maintain a safe practices manual which shall be made available at the dive location to each dive team member.
[42 FR 37668, July 22, 1977, as amended at 49 FR 18295, Apr. 30, 1984]
The employer shall comply with the following requirements prior to each diving operation, unless otherwise specified.
A list shall be kept at the dive location of the telephone or call numbers of the following:
Coast Guard Rescue Coordination Center.
Planning of a diving operation shall include an assessment of the safety and health aspects of the following:
To minimize hazards to the dive team, diving operations shall be coordinated with other activities in the vicinity which are likely to interfere with the diving operation.
The breathing gas supply system including reserve breathing gas supplies, masks, helmets, thermal protection, and bell handling mechanism (when appropriate) shall be inspected prior to each dive.
When diving from surfaces other than vessels in areas capable of supporting marine traffic, a rigid replica of the international code flag “A” at least one meter in height shall be displayed at the dive location in a manner which allows all-round visibility, and shall be illuminated during night diving operations.
[42 FR 37668, July 22, 1977, as amended at 47 FR 14706, Apr. 6, 1982; 54 FR 24334, June 7, 1989]
The employer shall comply with the following requirements which are applicable to each diving operation unless otherwise specified.
Decompression, repetitive, and no-decompression tables (as appropriate) shall be at the dive location.
A depth-time profile, including when appropriate any breathing gas changes, shall be maintained for each diver during the dive including decompression.
The working interval of a dive shall be terminated when:
The employer shall comply with the following requirements which are applicable after each diving operation, unless otherwise specified.
The employer shall:
[42 FR 37668, July 22, 1977, as amended at 49 FR 18295, Apr. 30, 1984]
Employers engaged in SCUBA diving shall comply with the following requirements, unless otherwise specified.
SCUBA diving shall not be conducted:
Employers engaged in surface-supplied air diving shall comply with the following requirements, unless otherwise specified.
Employers engaged in mixed-gas diving shall comply with the following requirements, unless otherwise specified.
Mixed-gas diving shall be conducted only when:
Employers engaged in diving operations involving liveboating shall comply with the following requirements.
Diving operations involving liveboating shall not be conducted:
increments to 100 feet beginning at the diver's end, and in 50 ft. increments thereafter;
Compressed gas cylinders shall:
[39 FR 23502, June 27, 1974, as amended at 49 FR 18295, Apr. 30, 1984; 51 FR 33033, Sept. 18, 1986]
[42 FR 37668, July 22, 1977, as amended at 45 FR 35281, May 23, 1980; 47 FR 14706, Apr. 6, 1982; 51 FR 34562, Sept. 29, 1986; 61 FR 9242, Mar. 7, 1996; 71 FR 16672, Apr. 3, 2006; 76 FR 33607, June 8, 2011; 76 FR 80740, Dec. 27, 2011]
The following disorders may restrict or limit occupational exposure to hyperbaric conditions depending on severity, presence of residual effects, response to therapy, number of occurrences, diving mode, or degree and duration of isolation.
History of seizure disorder other than early febrile convulsions.
Malignancies (active) unless treated and without recurrence for 5 yrs.
Chronic inability to equalize sinus and/or middle ear pressure.
Cystic or cavitary disease of the lungs.
Impaired organ function caused by alcohol or drug use.
Conditions requiring continuous medication for control (e.g., antihistamines, steroids, barbiturates, moodaltering drugs, or insulin).
Meniere's disease.
Hemoglobinopathies.
Obstructive or restrictive lung disease.
Vestibular end organ destruction.
Pneumothorax.
Cardiac abnormalities (e.g., pathological heart block, valvular disease, intraventricular conduction defects other than isolated right bundle branch block, angina pectoris, arrhythmia, coronary artery disease).
Juxta-articular osteonecrosis.
This appendix contains guidelines that will be used in conjunction with § 1910.401(a)(2)(iv) to determine those scientific diving programs which are exempt from the requirements for commercial diving. The guidelines are as follows:
1. The Diving Control Board consists of a majority of active scientific divers and has autonomous and absolute authority over the scientific diving program's operations.
2. The purpose of the project using scientific diving is the advancement of science; therefore, information and data resulting from the project are non-proprietary.
3. The tasks of a scientific diver are those of an observer and data gatherer. Construction and trouble-shooting tasks traditionally associated with commercial diving are not included within scientific diving.
4. Scientific divers, based on the nature of their activities, must use scientific expertise in studying the underwater environment and, therefore, are scientists or scientists in training.
[50 FR 1050, Jan. 9, 1985]
Paragraph (a)(3) of § 1910.401 specifies that an employer of recreational diving instructors and diving guides (hereafter, “divers” or “employees”) who complies with all of the conditions of this appendix need not provide a decompression chamber for these divers as required under §§ 1910.423(b)(2) or (c)(3) or 1910.426(b)(1).
1. Equipment Requirements for Rebreathers
2. Special Requirements for Closed-Circuit Rebreathers
functioning continuously; temperature compensated; and approved by the rebreather manufacturer.
3. O 2 Concentration in the Breathing Gas
The employer must ensure that the fraction of O 2 in the nitrox breathing-gas mixture:
4. Regulating O 2 Exposures and Diving Depth
5. Use of No-Decompression Limits
6. Mixing and Analyzing the Breathing Gas
7. Emergency Egress
8. Treating Diving-Related Medical Emergencies
9. Diving Logs and No-Decompression Tables
10. Diver Training
The employer must ensure that each diver receives training that enables the diver to perform work safely and effectively while using open-circuit SCUBAs or rebreathers supplied with nitrox breathing-gas mixtures. Accordingly, each diver must be able to demonstrate the ability to perform critical tasks safely and effectively, including, but not limited to: recognizing the effects of breathing excessive CO 2 and O 2 ; taking appropriate action after detecting excessive levels of CO 2 and O 2 ; and properly evaluating, operating, and maintaining their diving equipment under the diving conditions they encounter.
11. Testing Protocol for Determining the CO 2 Limits of Rebreather Canisters
| Ventilation rates (Lpm, ATPS 1 ) | Breathing machine tidal volumes (L) | Breathing machine frequencies (breaths per min.) | CO 2 injection rates (Lpm, STPD 2 ) |
|---|---|---|---|
| 22.5 | 1.5 | 15 | 0.90 |
| 40.0 | 2.0 | 20 | 1.35 |
| 62.5 | 2.5 | 25 | 2.25 |
| 1 ATPS means ambient temperature and pressure, saturated with water. | |||
| 2 STPD means standard temperature and pressure, dry; the standard temperature is 32 degrees F (0 degrees C). |
1 NEDU can provide the manufacturer with information on the temperature of a diver's exhaled breath at various water temperatures and ventilation rates, as well as techniques and procedures used to maintain these temperatures during the testing trials.
[69 FR 7363, Feb. 17, 2004]
The following definitions apply to this section:
Aerosol-generating procedure means a medical procedure that generates aerosols that can be infectious and are of respirable size. For the purposes of this section, only the following medical procedures are considered aerosol-generating procedures: Open suctioning of airways; sputum induction; cardiopulmonary resuscitation; endotracheal intubation and extubation; non-invasive ventilation ( e.g., BiPAP, CPAP); bronchoscopy; manual ventilation; medical/surgical/postmortem procedures using oscillating bone saws; and dental procedures involving: Ultrasonic scalers; high-speed dental handpieces; air/water syringes; air polishing; and air abrasion.
Airborne infection isolation room (AIIR) means a dedicated negative pressure patient-care room, with special air handling capability, which is used to isolate persons with a suspected or confirmed airborne-transmissible infectious disease. AIIRs include both permanent rooms and temporary structures ( e.g., a booth, tent or other enclosure designed to operate under negative pressure).
Ambulatory care means healthcare services performed on an outpatient basis, without admission to a hospital or other facility. It is provided in settings such as: Offices of physicians and other health care professionals; hospital outpatient departments; ambulatory surgical centers; specialty clinics or centers ( e.g., dialysis, infusion, medical imaging); and urgent care clinics. Ambulatory care does not include home healthcare settings for the purposes of this section.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Clean/cleaning means the removal of dirt and impurities, including germs, from surfaces using soap and water or other cleaning agents. Cleaning alone reduces germs on surfaces by removing contaminants and may also weaken or damage some of the virus particles, which decreases risk of infection from surfaces.
Close contact means being within 6 feet of any other person for a cumulative total of 15 minutes or more over a 24-hour period during that person's potential period of transmission. The potential transmission period runs from 2 days before the person felt sick (or, for asymptomatic people, 2 days prior to test specimen collection) until the time the person is isolated.
Common areas means indoor or outdoor locations under the control of the employer that more than one person may use or where people congregate ( e.g., building lobbies, reception areas, waiting rooms, restrooms, break rooms, eating areas, conference rooms).
COVID-19 (Coronavirus Disease 2019) means the respiratory disease caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). For clarity and ease of reference, this section refers to “COVID-19” when describing exposures or potential exposures to SARS-CoV-2.
COVID-19 positive and confirmed COVID-19 refer to a person who has a confirmed positive test for, or who has been diagnosed by a licensed healthcare provider with, COVID-19.
COVID-19 symptoms mean the following: Fever or chills; cough; shortness of breath or difficulty breathing; fatigue; muscle or body aches; headache; new loss of taste or smell; sore throat; congestion or runny nose; nausea or vomiting; diarrhea.
COVID-19 test means a test for SARS-CoV-2 that is:
Food and Drug Administration (FDA) or is authorized by an Emergency Use Authorization (EUA) from the FDA to diagnose current infection with the SARS-CoV-2 virus; and
Direct patient care means hands-on, face-to-face contact with patients for the purpose of diagnosis, treatment, and monitoring.
Disinfect/disinfection means using an EPA-registered, hospital-grade disinfectant on EPA's “List N” (incorporated by reference, § 1910.509), in accordance with manufacturers' instructions to kill germs on surfaces.
Elastomeric respirator means a tight-fitting respirator with a facepiece that is made of synthetic or rubber material that permits it to be disinfected, cleaned, and reused according to manufacturer's instructions. It is equipped with a replaceable cartridge(s), canister(s), or filter(s).
Facemask means a surgical, medical procedure, dental, or isolation mask that is FDA-cleared, authorized by an FDA EUA, or offered or distributed as described in an FDA enforcement policy. Facemasks may also be referred to as “medical procedure masks.”
Face shield means a device, typically made of clear plastic, that:
Filtering facepiece respirator means a negative pressure particulate respirator with a non-replaceable filter as an integral part of the facepiece or with the entire facepiece composed of the non-replaceable filtering medium.
Fully vaccinated means 2 weeks or more following the final dose of a COVID-19 vaccine.
Hand hygiene means the cleaning and/or disinfecting of one's hands by using standard handwashing methods with soap and running water or an alcohol-based hand rub that is at least 60% alcohol.
Healthcare services mean services that are provided to individuals by professional healthcare practitioners ( e.g., doctors, nurses, emergency medical personnel, oral health professionals) for the purpose of promoting, maintaining, monitoring, or restoring health. Healthcare services are delivered through various means including: Hospitalization, long-term care, ambulatory care, home health and hospice care, emergency medical response, and patient transport. For the purposes of this section, healthcare services include autopsies.
Healthcare support services mean services that facilitate the provision of healthcare services. Healthcare support services include patient intake/admission, patient food services, equipment and facility maintenance, housekeeping services, healthcare laundry services, medical waste handling services, and medical equipment cleaning/reprocessing services.
High-touch surfaces and equipment means any surface or piece of equipment that is repeatedly touched by more than one person ( e.g., doorknobs, light switches, countertops, handles, desks, tables, phones, keyboards, tools, toilets, faucets, sinks, credit card terminals, touchscreen-enabled devices).
Physical location means a site (including outdoor and indoor areas, a structure, or a group of structures) or an area within a site where work or any work-related activity ( e.g., taking breaks, going to the restroom, eating, entering, or exiting work) occurs. A physical location includes the entirety of any space associated with the site ( e.g., workstations, hallways, stairwells, breakrooms, bathrooms, elevators) and any other space that an employee might occupy in arriving, working, or leaving.
Powered air-purifying respirator (PAPR) means an air-purifying respirator that uses a blower to force the ambient air through air-purifying elements to the inlet covering.
Respirator means a type of personal protective equipment (PPE) that is certified by NIOSH under 42 CFR part 84 or is authorized under an EUA by the FDA. Respirators protect against airborne hazards by removing specific air contaminants from the ambient (surrounding) air or by supplying breathable air from a safe source. Common types of respirators include filtering facepiece respirators, elastomeric respirators, and PAPRs. Face coverings, facemasks, and face shields are not respirators.
Screen means asking questions to determine whether a person is COVID-19 positive or has symptoms of COVID-19.
Surgical mask means a mask that covers the user's nose and mouth and provides a physical barrier to fluids and particulate materials. The mask meets certain fluid barrier protection standards and Class I or Class II flammability tests. Surgical masks are generally regulated by FDA as Class II devices under 21 CFR 878.4040—Surgical apparel.
Vaccine means a biological product authorized or licensed by the FDA to prevent or provide protection against COVID-19, whether the substance is administered through a single dose or a series of doses.
Workplace means a physical location ( e.g., fixed, mobile) where the employer's work or operations are performed.
In settings where direct patient care is provided, the employer must:
Employers must develop and implement policies and procedures to adhere to Standard and Transmission-Based Precautions in accordance with CDC's “Guidelines for Isolation Precautions” (incorporated by reference, § 1910.509).
For aerosol-generating procedures performed on a person with suspected or confirmed COVID-19, the employer must provide:
At each fixed work location outside of direct patient care areas ( e.g., entryway/lobby, check-in desks, triage, hospital pharmacy windows, bill payment) where each employee is not separated from all other people by at least 6 feet of distance, the employer must install cleanable or disposable solid barriers, except where the employer can demonstrate it is not feasible. The barrier must be sized ( e.g., height and width) and located to block face-to-face pathways between individuals based on where each person would normally stand or sit. The barrier may have a pass-through space at the bottom for objects and merchandise.
The employer must make decisions regarding an employee's return to work after a COVID-19-related workplace removal in accordance with guidance from a licensed healthcare provider or CDC's “Isolation Guidance” (incorporated by reference, § 1910.509); and CDC's “Return to Work Healthcare Guidance” (incorporated by reference, § 1910.509).
The employer must support COVID-19 vaccination for each employee by providing reasonable time and paid leave ( e.g., paid sick leave, administrative leave) to each employee for vaccination and any side effects experienced following vaccination.
including how the disease is transmitted (including pre-symptomatic and asymptomatic transmission), the importance of hand hygiene to reduce the risk of spreading COVID-19 infections, ways to reduce the risk of spreading COVID-19 through the proper covering of the nose and mouth, the signs and symptoms of the disease, risk factors for severe illness, and when to seek medical attention;
The implementation of all requirements of this section, with the exception of any employee self-monitoring conducted under paragraph (l)(1)(i) of this section, must be at no cost to employees.
Employers with 10 or fewer employees on the effective date of this section are not required to comply with paragraph (q)(2) or (q)(3) of this section.
Employers with more than 10 employees on the effective date of this section must:
By the end of the next business day after a request, the employer must provide, for examination and copying:
This section is effective as of June 21, 2021.
This section applies only to respirator use in accordance with § 1910.502(f)(4).
The following definitions apply to this section:
COVID-19 (Coronavirus Disease 2019) means the respiratory disease caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). For clarity and ease of reference, this section refers to “COVID-19” when describing exposures or potential exposures to SARS-CoV-2.
Elastomeric respirator means a tight-fitting respirator with a facepiece that is made of synthetic or rubber material that permits it to be disinfected, cleaned, and reused according to manufacturer's instructions. It is equipped with a replaceable cartridge(s), canister(s), or filter(s).
Filtering facepiece respirator means a negative-pressure particulate respirator with a non-replaceable filter as an integral part of the facepiece or with the entire facepiece composed of the non-replaceable filtering medium.
Hand hygiene means the cleaning and/or disinfecting of one's hands by using standard handwashing methods with soap and running water or an alcohol-based hand rub that is at least 60% alcohol.
Respirator means a type of personal protective equipment (PPE) that is certified by the National Institute for Occupational Safety and Health (NIOSH) under 42 CFR part 84 or is authorized under an Emergency Use Authorization (EUA) by the US Food and Drug Administration. Respirators protect against airborne hazards by removing specific air contaminants from the ambient (surrounding) air or by supplying breathable air from a safe source. Common types of respirators include filtering facepiece respirators, elastomeric respirators, and PAPRs. Face coverings, facemasks, and face shields are not respirators.
Powered air-purifying respirator (PAPR) means an air-purifying respirator that uses a blower to force the ambient air through air-purifying elements to the inlet covering.
Tight-fitting respirator means a respirator in which the air pressure inside the facepiece is negative during inhalation with respect to the ambient air pressure outside the respirator ( e.g., filtering facepiece).
User seal check means an action conducted by the respirator user to determine if the respirator is properly seated to the face.
Where employees provide and use their own respirators, the employer must provide each employee with the following notice: Respirators can be an effective method of protection against COVID-19 hazards when properly selected and worn. Respirator use is encouraged to provide an additional level of comfort and protection for workers even in circumstances that do not require a respirator to be used. However, if a respirator is used improperly or not kept clean, the respirator itself can become a hazard to the worker. If your employer allows you to provide and use your own respirator, you need to take certain precautions to be sure that the respirator itself does not present a hazard. You should do the following:
Where employers provide respirators to their employees, the employer must comply with the following requirements:
The employer must ensure that each employee wearing a respirator receives training prior to first use and if they change the type of respirator, in a language and at a literacy level the employee understands, and comprehends at least the following:
Employers must require employees to discontinue use of a respirator when either the employee or a supervisor reports medical signs or symptoms ( e.g., shortness of breath, coughing, wheezing, chest pain, any other symptoms related to lung problems, cardiovascular symptoms) that are related to ability to use a respirator. Any employee who previously had a medical evaluation and was determined to not be medically fit to wear a respirator must not be provided with a respirator under this standard unless they are re-evaluated and medically cleared to use a respirator.
This section is effective as of June 21, 2021.
[86 FR 32620, June 21, 2021, as amended at 87 FR 3929, Jan. 26, 2022]
Each section of this subpart U, and each provision within those sections, is separate and severable from the other sections and provisions. If any provision of this subpart is held to be invalid or unenforceable on its face, or as applied to any person, entity, or circumstance, or is stayed or enjoined, that provision shall be construed so as to continue to give the maximum effect to the provision permitted by law, unless such holding shall be one of utter invalidity or unenforceability, in which event the provision shall be severable from this subpart and shall not affect the remainder of the subpart.
1600 Clifton Road, Atlanta, GA 30329; websites: https://www.cdc.gov/, https://www.cdc.gov/coronavirus/2019-ncov/communication/guidance.html, and https://www.cdc.gov/infectioncontrol/guidelines/.
Cleaning and Disinfecting Your Facility; Every Day and When Someone is Sick, updated April 5, 2021, IBR approved for § 1910.502(j).
Interim Infection Prevention and Control Recommendations for Healthcare Personnel During the Coronavirus Disease 2019 (COVID-19) Pandemic, updated February 23, 2021, IBR approved for §§ 1910.502(d) and (j).
2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings, updated July 2019, IBR approved for §§ 1910.502(e) and (f).
Guidelines for Environmental Infection Control in Health-Care Facilities, updated July 2019, IBR approved for § 1910.502(j).
Isolation If You Are Sick; Separate yourself from others if you have COVID-19, updated February 18, 2021, IBR approved for § 1910.502(l).
Return to Work Criteria for Healthcare Personnel with SARS-CoV-2 Infection (Interim Guidance), updated February 16, 2021, IBR approved for § 1910.502(l).
1200 Pennsylvania Avenue NW, Washington, DC 20460; website: https://www.epa.gov/.
Disinfectants for Coronavirus (COVID-19), updated April 9, 2021, IBR approved for § 1910.502(b).
1901 North Moore Street, Suite 808, Arlington, VA 22209; website: www.safetyequipment.org
Z87.1-2010, American National Standard for Occupational and Educational Personal Eye and Face Protection Devices, ANSI-approved April 13, 2010, IBR approved for § 1910.502(b).
Z87.1-2015, American National Standard for Occupational and Educational Personal Eye and Face Protection Devices, ANSI-approved May 28, 2015, IBR approved for § 1910.502(b).
Z87.1-2020, American National Standard for Occupational and Educational Personal Eye and Face Protection Devices, ANSI-approved March 11, 2020, IBR approved for § 1910.502(b).
[86 FR 32620, June 21, 2021, as amended at 87 FR 3929, Jan. 26, 2022]
An employee's exposure to any substance listed in Tables Z-1, Z-2, or Z-3 of this section shall be limited in accordance with the requirements of the following paragraphs of this section.
An employee's exposure to any substance in Table Z-1, the exposure limit of which is preceded by a “C”, shall at no time exceed the exposure limit given for that substance. If instantaneous monitoring is not feasible, then the ceiling shall be assessed as a 15-minute time weighted average exposure which shall not be exceeded at any time during the working day.
An employee's exposure to any substance in Table Z-1, the exposure limit of which is not preceded by a “C”, shall not exceed the 8-hour Time Weighted Average given for that substance in any 8-hour work shift of a 40-hour work week.
An employee's exposure to any substance listed in Table Z-2 shall not exceed the exposure limits specified as follows:
An employee's exposure to any substance listed in Table Z-2, in any 8-hour work shift of a 40-hour work week, shall not exceed the 8-hour time weighted average limit given for that substance in Table Z-2.
An employee's exposure to a substance listed in Table Z-2 shall not exceed at any time during an 8-hour shift the acceptable ceiling concentration limit given for the substance in the table, except for a time period, and up to a concentration not exceeding the maximum duration and concentration allowed in the column under “acceptable maximum peak above the acceptable ceiling concentration for an 8-hour shift.”
During an 8-hour work shift, an employee may be exposed to a concentration of Substance A (with a 10 ppm TWA, 25 ppm ceiling and 50 ppm peak) above 25 ppm (but never above 50 ppm) only for a maximum period of 10 minutes. Such exposure must be compensated by exposures to concentrations less than 10 ppm so that the cumulative exposure for the entire 8-hour work shift does not exceed a weighted average of 10 ppm.
An employee's exposure to any substance listed in Table Z-3, in any 8-hour work shift of a 40-hour work week, shall not exceed the 8-hour time weighted average limit given for that substance in the table.
The computation formula which shall apply to employee exposure to more than one substance for which 8-hour time weighted averages are listed in subpart Z of 29 CFR part 1910 in order to determine whether an employee is exposed over the regulatory limit is as follows:
a
a
b
b
n
n
Where:
E is the equivalent exposure for the working shift.
C is the concentration during any period of time T where the concentration remains constant.
T is the duration in hours of the exposure at the concentration C.
The value of E shall not exceed the 8-hour time weighted average specified in subpart Z of 29 CFR part 1910 for the substance involved.
Two hours exposure at 150 ppm
Two hours exposure at 75 ppm
Four hours exposure at 50 ppm
Substituting this information in the formula, we have
Since 81.25 ppm is less than 100 ppm, the 8-hour time weighted average limit, the exposure is acceptable.
m
1
1
2
2
n
n
Where:
m
C is the concentration of a particular contaminant.
L is the exposure limit for that substance specified in subpart Z of 29 CFR part 1910.
The value of E m shall not exceed unity (1).
| Substance | Actual concentration of 8-hour exposure (ppm) | 8-hour TWA PEL (ppm) |
|---|---|---|
| B | 500 | 1,000 |
| C | 45 | 200 |
| D | 40 | 200 |
Substituting in the formula, we have:
m
m
m
Since E m is less than unity (1), the exposure combination is within acceptable limits.
| Substance | CAS No. (c) | ppm (a) 1 | mg/m 3 (b) 1 | Skin designation |
|---|---|---|---|---|
| Acetaldehyde | 75-07-0 | 200 | 360 | |
| Acetic acid | 64-19-7 | 10 | 25 | |
| Acetic anhydride | 108-24-7 | 5 | 20 | |
| Acetone | 67-64-1 | 1000 | 2400 | |
| Acetonitrile | 75-05-8 | 40 | 70 | |
| 2-Acetylaminofluorine; see 1910.1014 | 53-96-3 | |||
| Acetylene dichloride; see 1,2-Dichloroethylene. | ||||
| Acetylene tetrabromide | 79-27-6 | 1 | 14 | |
| Acrolein | 107-02-8 | 0.1 | 0.25 | |
| Acrylamide | 79-06-1 | 0.3 | X | |
| Acrylonitrile; see 1910.1045 | 107-13-1 | |||
| Aldrin | 309-00-2 | 0.25 | X | |
| Allyl alcohol | 107-18-6 | 2 | 5 | X |
| Allyl chloride | 107-05-1 | 1 | 3 | |
| Allyl glycidyl ether (AGE) | 106-92-3 | (C)10 | (C)45 | |
| Allyl propyl disulfide | 2179-59-1 | 2 | 12 | |
| alpha-Alumina | 1344-28-1 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Aluminum, metal (as Al) | 7429-90-5 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| 4-Aminodiphenyl; see 1910.1011 | 92-67-1 | |||
| 2-Aminoethanol; see Ethanolamine. | ||||
| 2-Aminopyridine | 504-29-0 | 0.5 | 2 | |
| Ammonia | 7664-41-7 | 50 | 35 | |
| Ammonium sulfamate | 7773-06-0 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| n-Amyl acetate | 628-63-7 | 100 | 525 | |
| sec-Amyl acetate | 626-38-0 | 125 | 650 | |
| Aniline and homologs | 62-53-3 | 5 | 19 | X |
| Anisidine (o-, p-isomers) | 29191-52-4 | 0.5 | X | |
| Antimony and compounds (as Sb) | 7440-36-0 | 0.5 | ||
| ANTU (alpha Naphthylthiourea) | 86-88-4 | 0.3 | ||
| Arsenic, inorganic compounds (as As); see 1910.1018 | 7440-38-2 | |||
| Arsenic, organic compounds (as As) | 7440-38-2 | 0.5 | ||
| Arsine | 7784-42-1 | 0.05 | 0.2 | |
| Asbestos; see 1910.1001 | ( 4 ) | |||
| Azinphos-methyl | 86-50-0 | 0.2 | X | |
| Barium, soluble compounds (as Ba) | 7440-39-3 | 0.5 | ||
| Barium sulfate | 7727-43-7 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Benomyl | 17804-35-2 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Benzene; see 1910.1028 | 71-43-2 | |||
| See Table Z-2 for the limits applicable in the operations or sectors excluded in 1910.1028 d | ||||
| Benzidine; see 1910.1010 | 92-87-5 | |||
| p-Benzoquinone; see Quinone. | ||||
| Benzo(a)pyrene; see Coal tar pitch volatiles. | ||||
| Benzoyl peroxide | 94-36-0 | 5 | ||
| Benzyl chloride | 100-44-7 | 1 | 5 | |
| Beryllium and beryllium compounds (as Be); see 1926.1124 8 | 7440-41-7 | |||
| Biphenyl; see Diphenyl. | ||||
| Bismuth telluride, Undoped | 1304-82-1 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Boron oxide | 1303-86-2 | |||
| Total dust | 15 | |||
| Boron trifluoride | 7637-07-2 | (C)1 | (C)3 | |
| Bromine | 7726-95-6 | 0.1 | 0.7 | |
| Bromoform | 75-25-2 | 0.5 | 5 | X |
| Butadiene (1,3-Butadiene); See 29 CFR 1910.1051; 29 CFR 1910.19(l) | 106-99-0 | 1 ppm/5 ppm STEL | ||
| Butanethiol; see Butyl mercaptan. | ||||
| 2-Butanone (Methyl ethyl ketone) | 78-93-3 | 200 | 590 | |
| 2-Butoxyethanol | 111-76-2 | 50 | 240 | X |
| n-Butyl-acetate | 123-86-4 | 150 | 710 | |
| sec-Butyl acetate | 105-46-4 | 200 | 950 | |
| tert-Butyl acetate | 540-88-5 | 200 | 950 | |
| n-Butyl alcohol | 71-36-3 | 100 | 300 | |
| sec-Butyl alcohol | 78-92-2 | 150 | 450 | |
| tert-Butyl alcohol | 75-65-0 | 100 | 300 | |
| Butylamine | 109-73-9 | (C)5 | (C)15 | X |
| tert-Butyl chromate (as CrO 3 ); see 1910.1026 6 | 1189-85-1 | |||
| n-Butyl glycidyl ether (BGE) | 2426-08-6 | 50 | 270 | |
| Butyl mercaptan | 109-79-5 | 10 | 35 | |
| p-tert-Butyltoluene | 98-51-1 | 10 | 60 | |
| Cadmium (as Cd); see 1910.1027 | 7440-43-9 | |||
| Calcium carbonate | 1317-65-3 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Calcium hydroxide | 1305-62-0 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Calcium oxide | 1305-78-8 | 5 | ||
| Calcium silicate | 1344-95-2 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Calcium sulfate | 7778-18-9 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Camphor, synthetic | 76-22-2 | 2 | ||
| Carbaryl (Sevin) | 63-25-2 | 5 | ||
| Carbon black | 1333-86-4 | 3.5 | ||
| Carbon dioxide | 124-38-9 | 5000 | 9000 | |
| Carbon disulfide | 75-15-0 | ( 2 ) | ||
| Carbon monoxide | 630-08-0 | 50 | 55 | |
| Carbon tetrachloride | 56-23-5 | ( 2 ) | ||
| Cellulose | 9004-34-6 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Chlordane | 57-74-9 | 0.5 | X | |
| Chlorinated camphene | 8001-35-2 | 0.5 | X | |
| Chlorinated diphenyl oxide | 55720-99-5 | 0.5 | ||
| Chlorine | 7782-50-5 | (C)1 | (C)3 | |
| Chlorine dioxide | 10049-04-4 | 0.1 | 0.3 | |
| Chlorine trifluoride | 7790-91-2 | (C)0.1 | (C)0.4 | |
| Chloroacetaldehyde | 107-20-0 | (C)1 | (C)3 | |
| a-Chloroacetophenone (Phenacyl chloride) | 532-27-4 | 0.05 | 0.3 | |
| Chlorobenzene | 108-90-7 | 75 | 350 | |
| o-Chlorobenzylidene malononitrile | 2698-41-1 | 0.05 | 0.4 | |
| Chlorobromomethane | 74-97-5 | 200 | 1050 | |
| 2-Chloro-1,3-butadiene; see beta-Chloroprene. | ||||
| Chlorodiphenyl (42% Chlorine) (PCB) | 53469-21-9 | 1 | X | |
| Chlorodiphenyl (54% Chlorine) (PCB) | 11097-69-1 | 0.5 | X | |
| 1-Chloro-2,3-epoxypropane; see Epichlorohydrin. | ||||
| 2-Chloroethanol; see Ethylene chlorohydrin. | ||||
| Chloroethylene; see Vinyl chloride. | ||||
| Chloroform (Trichloromethane) | 67-66-3 | (C)50 | (C)240 | |
| bis(Chloromethyl) ether; see 1910.1008 | 542-88-1 | |||
| Chloromethyl methyl ether; see 1910.1006 | 107-30-2 | |||
| 1-Chloro-1-nitropropane | 600-25-9 | 20 | 100 | |
| Chloropicrin | 76-06-2 | 0.1 | 0.7 | |
| beta-Chloroprene | 126-99-8 | 25 | 90 | X |
| 2-Chloro-6-(trichloromethyl) pyridine | 1929-82-4 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Chromium (II) compounds. | ||||
| (as Cr) | 7440-47-3 | 0.5 | ||
| Chromium (III) compounds. | ||||
| (as Cr) | 7440-47-3 | 0.5 | ||
| Chromium (VI) compounds; See 1910.1026 5 | ||||
| Chromium metal and insol. salts (as Cr) | 7440-47-3 | 1 | ||
| Chrysene; see Coal tar pitch volatiles. | ||||
| Clopidol | 2971-90-6 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Coal dust (less than 5% SiO 2 ), respirable fraction | ( 3 ) | |||
| Coal dust (greater than or equal to 5% SiO 2 ), respirable fraction | ( 3 ) | |||
| Coal tar pitch volatiles (benzene soluble fraction), anthracene, BaP, phenanthrene, acridine, chrysene, pyrene | 65966-93-2 | 0.2 | ||
| Cobalt metal, dust, and fume (as Co) | 7440-48-4 | 0.1 | ||
| Coke oven emissions; see 1910.1029. | ||||
| Copper | 7440-50-8 | |||
| Fume (as Cu) | 0.1 | |||
| Dusts and mists (as Cu) | 1 | |||
| Cotton dust e ; see 1910.1043 | 1 | |||
| Crag herbicide (Sesone) | 136-78-7 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Cresol, all isomers | 1319-77-3 | 5 | 22 | X |
| Crotonaldehyde | 123-73-9; 4170-30-3 | 2 | 6 | |
| Cumene | 98-82-8 | 50 | 245 | X |
| Cyanides (as CN) | ( 4 ) | 5 | X | |
| Cyclohexane | 110-82-7 | 300 | 1050 | |
| Cyclohexanol | 108-93-0 | 50 | 200 | |
| Cyclohexanone | 108-94-1 | 50 | 200 | |
| Cyclohexene | 110-83-8 | 300 | 1015 | |
| Cyclopentadiene | 542-92-7 | 75 | 200 | |
| 2,4-D (Dichlorophenoxyacetic acid) | 94-75-7 | 10 | ||
| Decaborane | 17702-41-9 | 0.05 | 0.3 | X |
| Demeton (Systox) | 8065-48-3 | 0.1 | X | |
| Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone) | 123-42-2 | 50 | 240 | |
| 1,2-Diaminoethane; see Ethylenediamine. | ||||
| Diazomethane | 334-88-3 | 0.2 | 0.4 | |
| Diborane | 19287-45-7 | 0.1 | 0.1 | |
| 1,2-Dibromo-3-chloropropane (DBCP); see 1910.1044 | 96-12-8 | |||
| 1,2-Dibromoethane; see Ethylene dibromide. | ||||
| Dibutyl phosphate | 107-66-4 | 1 | 5 | |
| Dibutyl phthalate | 84-74-2 | 5 | ||
| o-Dichlorobenzene | 95-50-1 | (C)50 | (C)300 | |
| p-Dichlorobenzene | 106-46-7 | 75 | 450 | |
| 3,′-Dichlorobenzidine; see 1910.1007 | 91-94-1 | |||
| Dichlorodifluoromethane | 75-71-8 | 1000 | 4950 | |
| 1,3-Dichloro-5,5-dimethyl hydantoin | 118-52-5 | 0.2 | ||
| Dichlorodiphenyltrichloroethane (DDT) | 50-29-3 | 1 | X | |
| 1,1-Dichloroethane | 75-34-3 | 100 | 400 | |
| 1,2-Dichloroethane; see Ethylene dichloride. | ||||
| 1,2-Dichloroethylene | 540-59-0 | 200 | 790 | |
| Dichloroethyl ether | 111-44-4 | (C)15 | (C)90 | X |
| Dichloromethane; see Methylene chloride. | ||||
| Dichloromonofluoromethane | 75-43-4 | 1000 | 4200 | |
| 1,1-Dichloro-1-nitroethane | 594-72-9 | (C)10 | (C)60 | |
| 1,2-Dichloropropane; see Propylene dichloride. | ||||
| Dichlorotetrafluoroethane | 76-14-2 | 1000 | 7000 | |
| Dichlorvos (DDVP) | 62-73-7 | 1 | X | |
| Dicyclopentadienyl iron | 102-54-5 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Dieldrin | 60-57-1 | 0.25 | X | |
| Diethylamine | 109-89-7 | 25 | 75 | |
| 2-Diethylaminoethanol | 100-37-8 | 10 | 50 | X |
| Diethyl ether; see Ethyl ether. | ||||
| Difluorodibromomethane | 75-61-6 | 100 | 860 | |
| Diglycidyl ether (DGE) | 2238-07-5 | (C)0.5 | (C)2.8 | |
| Dihydroxybenzene; see Hydroquinone. | ||||
| Diisobutyl ketone | 108-83-8 | 50 | 290 | |
| Diisopropylamine | 108-18-9 | 5 | 20 | X |
| 4-Dimethylaminoazobenzene; see 1910.1015 | 60-11-7 | |||
| Dimethoxymethane; see Methylal. | ||||
| Dimethyl acetamide | 127-19-5 | 10 | 35 | X |
| Dimethylamine | 124-40-3 | 10 | 18 | |
| Dimethylaminobenzene; see Xylidine | ||||
| Dimethylaniline (N,N-Dimethylaniline) | 121-69-7 | 5 | 25 | X |
| Dimethylbenzene; see Xylene. | ||||
| Dimethyl-1,2-dibromo-2,2-dichloroethyl phosphate | 300-76-5 | 3 | ||
| Dimethylformamide | 68-12-2 | 10 | 30 | X |
| 2,6-Dimethyl-4-heptanone; see Diisobutyl ketone. | ||||
| 1,1-Dimethylhydrazine | 57-14-7 | 0.5 | 1 | X |
| Dimethylphthalate | 131-11-3 | 5 | ||
| Dimethyl sulfate | 77-78-1 | 1 | 5 | X |
| Dinitrobenzene (all isomers) | 1 | X | ||
| (ortho) | 528-29-0 | |||
| (meta) | 99-65-0 | |||
| (para) | 100-25-4 | |||
| Dinitro-o-cresol | 534-52-1 | 0.2 | X | |
| Dinitrotoluene | 25321-14-6 | 1.5 | X | |
| Dioxane (Diethylene dioxide) | 123-91-1 | 100 | 360 | X |
| Diphenyl (Biphenyl) | 92-52-4 | 0.2 | 1 | |
| Diphenylmethane diisocyanate; see Methylene bisphenyl isocyanate. | ||||
| Dipropylene glycol methyl ether | 34590-94-8 | 100 | 600 | X |
| Di-sec octyl phthalate (Di-(2-ethylhexyl) phthalate) | 117-81-7 | 5 | ||
| Emery | 12415-34-8 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Endrin | 72-20-8 | 0.1 | X | |
| Epichlorohydrin | 106-89-8 | 5 | 19 | X |
| EPN | 2104-64-5 | 0.5 | X | |
| 1,2-Epoxypropane; see Propylene oxide. | ||||
| 2,3-Epoxy-1-propanol; see Glycidol. | ||||
| Ethanethiol; see Ethyl mercaptan. | ||||
| Ethanolamine | 141-43-5 | 3 | 6 | |
| 2-Ethoxyethanol (Cellosolve) | 110-80-5 | 200 | 740 | X |
| 2-Ethoxyethyl acetate (Cellosolve acetate) | 111-15-9 | 100 | 540 | X |
| Ethyl acetate | 141-78-6 | 400 | 1400 | |
| Ethyl acrylate | 140-88-5 | 25 | 100 | X |
| Ethyl alcohol (Ethanol) | 64-17-5 | 1000 | 1900 | |
| Ethylamine | 75-04-7 | 10 | 18 | |
| Ethyl amyl ketone (5-Methyl-3-heptanone) | 541-85-5 | 25 | 130 | |
| Ethyl benzene | 100-41-4 | 100 | 435 | |
| Ethyl bromide | 74-96-4 | 200 | 890 | |
| Ethyl butyl ketone (3-Heptanone) | 106-35-4 | 50 | 230 | |
| Ethyl chloride | 75-00-3 | 1000 | 2600 | |
| Ethyl ether | 60-29-7 | 400 | 1200 | |
| Ethyl formate | 109-94-4 | 100 | 300 | |
| Ethyl mercaptan | 75-08-1 | (C)10 | (C)25 | |
| Ethyl silicate | 78-10-4 | 100 | 850 | |
| Ethylene chlorohydrin | 107-07-3 | 5 | 16 | X |
| Ethylenediamine | 107-15-3 | 10 | 25 | |
| Ethylene dibromide | 106-93-4 | ( 2 ) | ||
| Ethylene dichloride (1,2-Dichloroethane) | 107-06-2 | ( 2 ) | ||
| Ethylene glycol dinitrate | 628-96-6 | (C)0.2 | (C)1 | X |
| Ethylene glycol methyl acetate; see Methyl cellosolve acetate. | ||||
| Ethyleneimine; see 1910.1012 | 151-56-4 | |||
| Ethylene oxide; see 1910.1047 | 75-21-8 | |||
| Ethylidene chloride; see 1,1-Dichloroethane. | ||||
| N-Ethylmorpholine | 100-74-3 | 20 | 94 | X |
| Ferbam | 14484-64-1 | |||
| Total dust | 15 | |||
| Ferrovanadium dust | 12604-58-9 | 1 | ||
| Fluorides (as F) | ( 4 ) | 2.5 | ||
| Fluorine | 7782-41-4 | 0.1 | 0.2 | |
| Fluorotrichloromethane (Trichlorofluoromethane) | 75-69-4 | 1000 | 5600 | |
| Formaldehyde; see 1910.1048 | 50-00-0 | |||
| Formic acid | 64-18-6 | 5 | 9 | |
| Furfural | 98-01-1 | 5 | 20 | X |
| Furfuryl alcohol | 98-00-0 | 50 | 200 | |
| Grain dust (oat, wheat, barley) | 10 | |||
| Glycerin (mist) | 56-81-5 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Glycidol | 556-52-5 | 50 | 150 | |
| Glycol monoethyl ether; see 2-Ethoxyethanol. | ||||
| Graphite, natural, respirable dust | 7782-42-5 | ( 3 ) | ||
| Graphite, synthetic | ||||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Guthion; see Azinphos methyl. | ||||
| Gypsum | 13397-24-5 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Hafnium | 7440-58-6 | 0.5 | ||
| Heptachlor | 76-44-8 | 0.5 | X | |
| Heptane (n-Heptane) | 142-82-5 | 500 | 2000 | |
| Hexachloroethane | 67-72-1 | 1 | 10 | X |
| Hexachloronaphthalene | 1335-87-1 | 0.2 | X | |
| n-Hexane | 110-54-3 | 500 | 1800 | |
| 2-Hexanone (Methyl n-butyl ketone) | 591-78-6 | 100 | 410 | |
| Hexone (Methyl isobutyl ketone) | 108-10-1 | 100 | 410 | |
| sec-Hexyl acetate | 108-84-9 | 50 | 300 | |
| Hydrazine | 302-01-2 | 1 | 1.3 | X |
| Hydrogen bromide | 10035-10-6 | 3 | 10 | |
| Hydrogen chloride | 7647-01-0 | (C)5 | (C)7 | |
| Hydrogen cyanide | 74-90-8 | 10 | 11 | X |
| Hydrogen fluoride (as F) | 7664-39-3 | ( 2 ) | ||
| Hydrogen peroxide | 7722-84-1 | 1 | 1.4 | |
| Hydrogen selenide (as Se) | 7783-07-5 | 0.05 | 0.2 | |
| Hydrogen sulfide | 7783-06-4 | ( 2 ) | ||
| Hydroquinone | 123-31-9 | 2 | ||
| Iodine | 7553-56-2 | (C)0.1 | (C)1 | |
| Iron oxide fume | 1309-37-1 | 10 | ||
| Isoamyl acetate | 123-92-2 | 100 | 525 | |
| Isoamyl alcohol (primary and secondary) | 123-51-3 | 100 | 360 | |
| Isobutyl acetate | 110-19-0 | 150 | 700 | |
| Isobutyl alcohol | 78-83-1 | 100 | 300 | |
| Isophorone | 78-59-1 | 25 | 140 | |
| Isopropyl acetate | 108-21-4 | 250 | 950 | |
| Isopropyl alcohol | 67-63-0 | 400 | 980 | |
| Isopropylamine | 75-31-0 | 5 | 12 | |
| Isopropyl ether | 108-20-3 | 500 | 2100 | |
| Isopropyl glycidyl ether (IGE) | 4016-14-2 | 50 | 240 | |
| Kaolin | 1332-58-7 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Ketene | 463-51-4 | 0.5 | 0.9 | |
| Lead, inorganic (as Pb); see 1910.1025 | 7439-92-1 | |||
| Limestone | 1317-65-3 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Lindane | 58-89-9 | 0.5 | X | |
| Lithium hydride | 7580-67-8 | 0.025 | ||
| L.P.G. (Liquefied petroleum gas) | 68476-85-7 | 1000 | 1800 | |
| Magnesite | 546-93-0 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Magnesium oxide fume | 1309-48-4 | |||
| Total particulate | 15 | |||
| Malathion | 121-75-5 | |||
| Total dust | 15 | X | ||
| Maleic anhydride | 108-31-6 | 0.25 | 1 | |
| Manganese compounds (as Mn) | 7439-96-5 | (C)5 | ||
| Manganese fume (as Mn) | 7439-96-5 | (C)5 | ||
| Marble | 1317-65-3 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Mercury (aryl and inorganic) (as Hg) | 7439-97-6 | ( 2 ) | ||
| Mercury (organo) alkyl compounds (as Hg) | 7439-97-6 | ( 2 ) | ||
| Mercury (vapor) (as Hg) | 7439-97-6 | ( 2 ) | ||
| Mesityl oxide | 141-79-7 | 25 | 100 | |
| Methanethiol; see Methyl mercaptan. | ||||
| Methoxychlor | 72-43-5 | |||
| Total dust | 15 | |||
| 2-Methoxyethanol (Methyl cellosolve) | 109-86-4 | 25 | 80 | X |
| 2-Methoxyethyl acetate (Methyl cellosolve acetate) | 110-49-6 | 25 | 120 | X |
| Methyl acetate | 79-20-9 | 200 | 610 | |
| Methyl acetylene (Propyne) | 74-99-7 | 1000 | 1650 | |
| Methyl acetylene-propadiene mixture (MAPP) | 1000 | 1800 | ||
| Methyl acrylate | 96-33-3 | 10 | 35 | X |
| Methylal (Dimethoxy-methane) | 109-87-5 | 1000 | 3100 | |
| Methyl alcohol | 67-56-1 | 200 | 260 | |
| Methylamine | 74-89-5 | 10 | 12 | |
| Methyl amyl alcohol; see Methyl isobutyl carbinol. | ||||
| Methyl n-amyl ketone | 110-43-0 | 100 | 465 | |
| Methyl bromide | 74-83-9 | (C)20 | (C)80 | X |
| Methyl butyl ketone; see 2-Hexanone. | ||||
| Methyl cellosolve; see 2-Methoxyethanol. | ||||
| Methyl cellosolve acetate; see 2-Methoxyethyl acetate. | ||||
| Methyl chloride | 74-87-3 | ( 2 ) | ||
| Methyl chloroform (1,1,1-Trichloroethane) | 71-55-6 | 350 | 1900 | |
| Methylcyclohexane | 108-87-2 | 500 | 2000 | |
| Methylcyclohexanol | 25639-42-3 | 100 | 470 | |
| o-Methylcyclohexanone | 583-60-8 | 100 | 460 | X |
| Methylene chloride | 75-09-2 | ( 2 ) | ||
| Methyl ethyl ketone (MEK); see 2-Butanone. | ||||
| Methyl formate | 107-31-3 | 100 | 250 | |
| Methyl hydrazine (Monomethyl hydrazine) | 60-34-4 | (C)0.2 | (C)0.35 | X |
| Methyl iodide | 74-88-4 | 5 | 28 | X |
| Methyl isoamyl ketone | 110-12-3 | 100 | 475 | |
| Methyl isobutyl carbinol | 108-11-2 | 25 | 100 | X |
| Methyl isobutyl ketone; see Hexone. | ||||
| Methyl isocyanate | 624-83-9 | 0.02 | 0.05 | X |
| Methyl mercaptan | 74-93-1 | (C)10 | (C)20 | |
| Methyl methacrylate | 80-62-6 | 100 | 410 | |
| Methyl propyl ketone; see 2-Pentanone. | ||||
| alpha-Methyl styrene | 98-83-9 | (C)100 | (C)480 | |
| Methylene bisphenyl isocyanate (MDI) | 101-68-8 | (C)0.02 | (C)0.2 | |
| Mica; see Silicates. | ||||
| Molybdenum (as Mo) | 7439-98-7 | |||
| Soluble compounds | 5 | |||
| Insoluble compounds. | ||||
| Total dust | 15 | |||
| Monomethyl aniline | 100-61-8 | 2 | 9 | X |
| Monomethyl hydrazine; see Methyl hydrazine. | ||||
| Morpholine | 110-91-8 | 20 | 70 | X |
| Naphtha (Coal tar) | 8030-30-6 | 100 | 400 | |
| Naphthalene | 91-20-3 | 10 | 50 | |
| alpha-Naphthylamine; see 1910.1004 | 134-32-7 | |||
| beta-Naphthylamine; see 1910.1009 | 91-59-8 | |||
| Nickel carbonyl (as Ni) | 13463-39-3 | 0.001 | 0.007 | |
| Nickel, metal and insoluble compounds (as Ni) | 7440-02-0 | 1 | ||
| Nickel, soluble compounds (as Ni) | 7440-02-0 | 1 | ||
| Nicotine | 54-11-5 | 0.5 | X | |
| Nitric acid | 7697-37-2 | 2 | 5 | |
| Nitric oxide | 10102-43-9 | 25 | 30 | |
| p-Nitroaniline | 100-01-6 | 1 | 6 | X |
| Nitrobenzene | 98-95-3 | 1 | 5 | X |
| p-Nitrochlorobenzene | 100-00-5 | 1 | X | |
| 4-Nitrodiphenyl; see 1910.1003 | 92-93-3 | |||
| Nitroethane | 79-24-3 | 100 | 310 | |
| Nitrogen dioxide | 10102-44-0 | (C)5 | (C)9 | |
| Nitrogen trifluoride | 7783-54-2 | 10 | 29 | |
| Nitroglycerin | 55-63-0 | (C)0.2 | (C)2 | X |
| Nitromethane | 75-52-5 | 100 | 250 | |
| 1-Nitropropane | 108-03-2 | 25 | 90 | |
| 2-Nitropropane | 79-46-9 | 25 | 90 | |
| N-Nitrosodimethylamine; see 1910.1016. | ||||
| Nitrotoluene (all isomers) | 5 | 30 | X | |
| o-isomer | 88-72-2 | |||
| m-isomer | 99-08-1 | |||
| p-isomer | 99-99-0 | |||
| Nitrotrichloromethane; see Chloropicrin. | ||||
| Octachloronaphthalene | 2234-13-1 | 0.1 | X | |
| Octane | 111-65-9 | 500 | 2350 | |
| Oil mist, mineral | 8012-95-1 | 5 | ||
| Osmium tetroxide (as Os) | 20816-12-0 | 0.002 | ||
| Oxalic acid | 144-62-7 | 1 | ||
| Oxygen difluoride | 7783-41-7 | 0.05 | 0.1 | |
| Ozone | 10028-15-6 | 0.1 | 0.2 | |
| Paraquat, respirable dust | 4685-14-7; 1910-42-5; 2074-50-2 | 0.5 | X | |
| Parathion | 56-38-2 | 0.1 | X | |
| Particulates not otherwise regulated (PNOR) f . | ||||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| PCB; see Chlorodiphenyl (42% and 54% chlorine). | ||||
| Pentaborane | 19624-22-7 | 0.005 | 0.01 | |
| Pentachloronaphthalene | 1321-64-8 | 0.5 | X | |
| Pentachlorophenol | 87-86-5 | 0.5 | X | |
| Pentaerythritol | 115-77-5 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Pentane | 109-66-0 | 1000 | 2950 | |
| 2-Pentanone (Methyl propyl ketone) | 107-87-9 | 200 | 700 | |
| Perchloroethylene (Tetrachloroethylene) | 127-18-4 | ( 2 ) | ||
| Perchloromethyl mercaptan | 594-42-3 | 0.1 | 0.8 | |
| Perchloryl fluoride | 7616-94-6 | 3 | 13.5 | |
| Petroleum distillates (Naphtha) (Rubber Solvent) | 500 | 2000 | ||
| Phenol | 108-95-2 | 5 | 19 | X |
| p-Phenylene diamine | 106-50-3 | 0.1 | X | |
| Phenyl ether, vapor | 101-84-8 | 1 | 7 | |
| Phenyl ether-biphenyl mixture, vapor | 1 | 7 | ||
| Phenylethylene; see Styrene. | ||||
| Phenyl glycidyl ether (PGE) | 122-60-1 | 10 | 60 | |
| Phenylhydrazine | 100-63-0 | 5 | 22 | X |
| Phosdrin (Mevinphos) | 7786-34-7 | 0.1 | X | |
| Phosgene (Carbonyl chloride) | 75-44-5 | 0.1 | 0.4 | |
| Phosphine | 7803-51-2 | 0.3 | 0.4 | |
| Phosphoric acid | 7664-38-2 | 1 | ||
| Phosphorus (yellow) | 7723-14-0 | 0.1 | ||
| Phosphorus pentachloride | 10026-13-8 | 1 | ||
| Phosphorus pentasulfide | 1314-80-3 | 1 | ||
| Phosphorus trichloride | 7719-12-2 | 0.5 | 3 | |
| Phthalic anhydride | 85-44-9 | 2 | 12 | |
| Picloram | 1918-02-1 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Picric acid | 88-89-1 | 0.1 | X | |
| Pindone (2-Pivalyl-1,3-indandione) | 83-26-1 | 0.1 | ||
| Plaster of Paris | 26499-65-0 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Platinum (as Pt) | 7440-06-4 | |||
| Metal | ||||
| Soluble salts | 0.002 | |||
| Portland cement | 65997-15-1 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Propane | 74-98-6 | 1000 | 1800 | |
| beta-Propriolactone; see 1910.1013 | 57-57-8 | |||
| n-Propyl acetate | 109-60-4 | 200 | 840 | |
| n-Propyl alcohol | 71-23-8 | 200 | 500 | |
| n-Propyl nitrate | 627-13-4 | 25 | 110 | |
| Propylene dichloride | 78-87-5 | 75 | 350 | |
| Propylene imine | 75-55-8 | 2 | 5 | X |
| Propylene oxide | 75-56-9 | 100 | 240 | |
| Propyne; see Methyl acetylene. | ||||
| Pyrethrum | 8003-34-7 | 5 | ||
| Pyridine | 110-86-1 | 5 | 15 | |
| Quinone | 106-51-4 | 0.1 | 0.4 | |
| RDX; see Cyclonite. | ||||
| Rhodium (as Rh), metal fume and insoluble compounds | 7440-16-6 | 0.1 | ||
| Rhodium (as Rh), soluble compounds | 7440-16-6 | 0.001 | ||
| Ronnel | 299-84-3 | 15 | ||
| Rotenone | 83-79-4 | 5 | ||
| Rouge | ||||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Selenium compounds (as Se) | 7782-49-2 | 0.2 | ||
| Selenium hexafluoride (as Se) | 7783-79-1 | 0.05 | 0.4 | |
| Silica, amorphous, precipitated and gel | 112926-00-8 | ( 3 ) | ||
| Silica, amorphous, diatomaceous earth, containing less than 1% crystalline silica | 61790-53-2 | ( 3 ) | ||
| Silica, crystalline, respirable dust | ||||
| Cristobalite; see 1910.1053 7 | 14464-46-1 | |||
| Quartz; see 1910.1053 7 | 14808-60-7 | |||
| Tripoli (as quartz); see 1910.1053 7 | 1317-95-9 | |||
| Tridymite; see 1910.1053 7 | 15468-32-3 | |||
| Silica, fused, respirable dust | 60676-86-0 | ( 3 ) | ||
| Silicates (less than 1% crystalline silica) | ||||
| Mica (respirable dust) | 12001-26-2 | ( 3 ) | ||
| Soapstone, total dust | ( 3 ) | |||
| Soapstone, respirable dust | ( 3 ) | |||
| Talc (containing asbestos); use asbestos limit; see 29 CFR 1910.1001 | ( 3 ) | |||
| Talc (containing no asbestos), respirable dust | 14807-96-6 | ( 3 ) | ||
| Tremolite, asbestiform; see 1910.1001. | ||||
| Silicon | 7440-21-3 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Silicon carbide | 409-21-2 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Silver, metal and soluble compounds (as Ag) | 7440-22-4 | 0.01 | ||
| Soapstone; see Silicates. | ||||
| Sodium fluoroacetate | 62-74-8 | 0.05 | X | |
| Sodium hydroxide | 1310-73-2 | 2 | ||
| Starch | 9005-25-8 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Stibine | 7803-52-3 | 0.1 | 0.5 | |
| Stoddard solvent | 8052-41-3 | 500 | 2900 | |
| Strychnine | 57-24-9 | 0.15 | ||
| Styrene | 100-42-5 | ( 2 ) | ||
| Sucrose | 57-50-1 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Sulfur dioxide | 7446-09-5 | 5 | 13 | |
| Sulfur hexafluoride | 2551-62-4 | 1000 | 6000 | |
| Sulfuric acid | 7664-93-9 | 1 | ||
| Sulfur monochloride | 10025-67-9 | 1 | 6 | |
| Sulfur pentafluoride | 5714-22-7 | 0.025 | 0.25 | |
| Sulfuryl fluoride | 2699-79-8 | 5 | 20 | |
| Systox; see Demeton. | ||||
| 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) | 93-76-5 | 10 | ||
| Talc; see Silicates. | ||||
| Tantalum, metal and oxide dust | 7440-25-7 | 5 | ||
| TEDP (Sulfotep) | 3689-24-5 | 0.2 | X | |
| Tellurium and compounds (as Te) | 13494-80-9 | 0.1 | ||
| Tellurium hexafluoride (as Te) | 7783-80-4 | 0.02 | 0.2 | |
| Temephos | 3383-96-8 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| TEPP (Tetraethyl pyrophosphate) | 107-49-3 | 0.05 | X | |
| Terphenyls | 26140-60-3 | (C)1 | (C)9 | |
| 1,1,1,2-Tetrachloro-2,2-difluoroethane | 76-11-9 | 500 | 4170 | |
| 1,1,2,2-Tetrachloro-1,2-difluoroethane | 76-12-0 | 500 | 4170 | |
| 1,1,2,2-Tetrachloroethane | 79-34-5 | 5 | 35 | X |
| Tetrachloroethylene; see Perchloroethylene. | ||||
| Tetrachloromethane; see Carbon tetrachloride. | ||||
| Tetrachloronaphthalene | 1335-88-2 | 2 | X | |
| Tetraethyl lead (as Pb) | 78-00-2 | 0.075 | X | |
| Tetrahydrofuran | 109-99-9 | 200 | 590 | |
| Tetramethyl lead (as Pb) | 75-74-1 | 0.075 | X | |
| Tetramethyl succinonitrile | 3333-52-6 | 0.5 | 3 | X |
| Tetranitromethane | 509-14-8 | 1 | 8 | |
| Tetryl (2,4,6-Trinitrophenylmethylnitramine) | 479-45-8 | 1.5 | X | |
| Thallium, soluble compounds (as Tl) | 7440-28-0 | 0.1 | X | |
| 4,4′-Thiobis (6-tert, Butyl-m-cresol) | 96-69-5 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Thiram | 137-26-8 | 5 | ||
| Tin, inorganic compounds (except oxides) (as Sn) | 7440-31-5 | 2 | ||
| Tin, organic compounds (as Sn) | 7440-31-5 | 0.1 | ||
| Titanium dioxide | 13463-67-7 | |||
| Total dust | 15 | |||
| Toluene | 108-88-3 | ( 2 ) | ||
| Toluene-2,4-diisocyanate (TDI) | 584-84-9 | (C)0.02 | (C)0.14 | |
| o-Toluidine | 95-53-4 | 5 | 22 | X |
| Toxaphene; see Chlorinated camphene. | ||||
| Tremolite; see Silicates. | ||||
| Tributyl phosphate | 126-73-8 | 5 | ||
| 1,1,1-Trichloroethane; see Methyl chloroform. | ||||
| 1,1,2-Trichloroethane | 79-00-5 | 10 | 45 | X |
| Trichloroethylene | 79-01-6 | ( 2 ) | ||
| Trichloromethane; see Chloroform. | ||||
| Trichloronaphthalene | 1321-65-9 | 5 | X | |
| 1,2,3-Trichloropropane | 96-18-4 | 50 | 300 | |
| 1,1,2-Trichloro-1,2,2-trifluoroethane | 76-13-1 | 1000 | 7600 | |
| Triethylamine | 121-44-8 | 25 | 100 | |
| Trifluorobromomethane | 75-63-8 | 1000 | 6100 | |
| 2,4,6-Trinitrophenol; see Picric acid. | ||||
| 2,4,6-Trinitrophenylmethylnitramine; see Tetryl. | ||||
| 2,4,6-Trinitrotoluene (TNT) | 118-96-7 | 1.5 | X | |
| Triorthocresyl phosphate | 78-30-8 | 0.1 | ||
| Triphenyl phosphate | 115-86-6 | 3 | ||
| Turpentine | 8006-64-2 | 100 | 560 | |
| Uranium (as U) | 7440-61-1 | |||
| Soluble compounds | 0.05 | |||
| Insoluble compounds | 0.25 | |||
| Vanadium | 1314-62-1 | |||
| Respirable dust (as V 2 O 5 ) | (C)0.5 | |||
| Fume (as V 2 O 5 ) | (C)0.1 | |||
| Vegetable oil mist | ||||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Vinyl benzene; see Styrene. | ||||
| Vinyl chloride; see 1910.1017 | 75-01-4 | |||
| Vinyl cyanide; see Acrylonitrile. | ||||
| Vinyl toluene | 25013-15-4 | 100 | 480 | |
| Warfarin | 81-81-2 | 0.1 | ||
| Xylenes (o-, m-, p-isomers) | 1330-20-7 | 100 | 435 | |
| Xylidine | 1300-73-8 | 5 | 25 | X |
| Yttrium | 7440-65-5 | 1 | ||
| Zinc chloride fume | 7646-85-7 | 1 | ||
| Zinc oxide fume | 1314-13-2 | 5 | ||
| Zinc oxide | 1314-13-2 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Zinc stearate | 557-05-1 | |||
| Total dust | 15 | |||
| Respirable fraction | 5 | |||
| Zirconium compounds (as Zr) | 7440-67-7 | 5 | ||
| 1 The PELs are 8-hour TWAs unless otherwise noted; a (C) designation denotes a ceiling limit. They are to be determined from breathing-zone air samples. | ||||
| (a) Parts of vapor or gas per million parts of contaminated air by volume at 25 °C and 760 torr. | ||||
| (b) Milligrams of substance per cubic meter of air. When entry is in this column only, the value is exact; when listed with a ppm entry, it is approximate. | ||||
| (c) The CAS number is for information only. Enforcement is based on the substance name. For an entry covering more than one metal compound, measured as the metal, the CAS number for the metal is given—not CAS numbers for the individual compounds. | ||||
| (d) The final benzene standard in 1910.1028 applies to all occupational exposures to benzene except in some circumstances the distribution and sale of fuels, sealed containers and pipelines, coke production, oil and gas drilling and production, natural gas processing, and the percentage exclusion for liquid mixtures; for the excepted subsegments, the benzene limits in Table Z-2 apply. See 1910.1028 for specific circumstances. | ||||
| (e) This 8-hour TWA applies to respirable dust as measured by a vertical elutriator cotton dust sampler or equivalent instrument. The time-weighted average applies to the cottom waste processing operations of waste recycling (sorting, blending, cleaning and willowing) and garnetting. See also 1910.1043 for cotton dust limits applicable to other sectors. | ||||
| (f) All inert or nuisance dusts, whether mineral, inorganic, or organic, not listed specifically by substance name are covered by the Particulates Not Otherwise Regulated (PNOR) limit which is the same as the inert or nuisance dust limit of Table Z-3. | ||||
| 2 See Table Z-2. | ||||
| 3 See Table Z-3. | ||||
| 4 Varies with compound. | ||||
| 5 See Table Z-2 for the exposure limit for any operations or sectors where the exposure limit in § 1910.1026 is stayed or is otherwise not in effect. | ||||
| 6 If the exposure limit in § 1910.1026 is stayed or is otherwise not in effect, the exposure limit is a ceiling of 0.1 mg/m 3 . | ||||
| 7 See Table Z-3 for the exposure limit for any operations or sectors where the exposure limit in § 1910.1053 is stayed or is otherwise not in effect. | ||||
| 8 See Table Z-2 for the exposure limits for any operations or sectors where the exposure limits in § 1910.1024 are stayed or otherwise not in effect. |
| Substance | 8-hour time weighted average | Acceptable ceiling concentration | Acceptable maximum peak above the acceptable ceiling concentration for an 8-hr shift | |
|---|---|---|---|---|
| Concentration | Maximum duration | |||
| Benzene a (Z37.40-1969) | 10 ppm | 25 ppm | 50 ppm | 10 minutes. |
| Beryllium and beryllium compounds (Z37.29-1970) d | 2 µg/m 3 | 5 µg/m 3 | 25 µg/m 3 | 30 minutes. |
| Cadmium fume b (Z37.5-1970) | 0.1 mg/m 3 | 0.3 mg/m 3 | ||
| Cadmium dust b (Z37.5-1970) | 0.2 mg/m 3 | 0.6 mg/m 3 | ||
| Carbon disulfide (Z37.3-1968) | 20 ppm | 30 ppm | 100 ppm | 30 minutes. |
| Carbon tetrachloride (Z37.17-1967) | 10 ppm | 25 ppm | 200 ppm | 5 min. in any 4 hrs. |
| Chromic acid and chromates (Z37.7-1971) (as CrO 3 ) c | 1 mg/10m 3 | |||
| Ethylene dibromide (Z37.31-1970) | 20 ppm | 30 ppm | 50 ppm | 5 minutes. |
| Ethylene dichloride (Z37.21-1969) | 50 ppm | 100 ppm | 200 ppm | 5 min. in any 3 hrs. |
| Fluoride as dust (Z37.28-1969) | 2.5 mg/m 3 | |||
| Formaldehyde; see 1910.1048 | ||||
| Hydrogen fluoride (Z37.28-1969) | 3 ppm | |||
| Hydrogen sulfide (Z37.2-1966) | 20 ppm | 50 ppm | 10 mins. once, only if no other meas. exp. occurs. | |
| Mercury (Z37.8-1971) | 1 mg/10m 3 | |||
| Methyl chloride (Z37.18-1969) | 100 ppm | 200 ppm | 300 ppm | 5 mins. in any 3 hrs. |
| Methylene Chloride: See § 1919.52. | ||||
| Organo (alkyl) mercury (Z37.30-1969) | 0.01 mg/m 3 | 0.04 mg/m 3 | ||
| Styrene (Z37.15-1969) | 100 ppm | 200 ppm | 600 ppm | 5 mins. in any 3 hrs. |
| Tetrachloroethylene (Z37.22-1967) | 100 ppm | 200 ppm | 300 ppm | 5 mins. in any 3 hrs. |
| Toluene (Z37.12-1967) | 200 ppm | 300 ppm | 500 ppm | 10 minutes. |
| Trichloroethylene (Z37.19-1967) | 100 ppm | 200 ppm | 300 ppm | 5 mins. in any 2 hrs. |
| a This standard applies to the industry segments exempt from the 1 ppm 8-hour TWA and 5 ppm STEL of the benzene standard at 1910.1028. | ||||
| b This standard applies to any operations or sectors for which the Cadmium standard, 1910.1027, is stayed or otherwise not in effect. | ||||
| c This standard applies to any operations or sectors for which the exposure limit in the Chromium (VI) standard, § 1910.1026, is stayed or is otherwise not in effect. | ||||
| d This standard applies to any operations or sectors for which the exposure limits in the beryllium standard, § 1910.1024, are stayed or is otherwise not in effect. |
| Substance | mppcf a | mg/m 3 |
|---|---|---|
| Silica: | ||
| Crystalline | ||
| Quartz (Respirable) f | 250 b | 10 mg/m 3 e |
| % SiO 2 + 5 | % SiO 2 + 2 | |
| Cristobalite: Use 1 ⁄ 2 the value calculated from the count or mass formulae for quartz f | ||
| Tridymite: Use 1 ⁄ 2 the value calculated from the formulae for quartz f | ||
| Amorphous, including natural diatomaceous earth | 20 | 80 mg/m 3 |
| %SiO 2 | ||
| Silicates (less than 1% crystalline silica): | ||
| Mica | 20 | |
| Soapstone | 20 | |
| Talc (not containing asbestos) | 20 c | |
| Talc (containing asbestos) Use asbestos limit | ||
| Tremolite, asbestiform (see 29 CFR 1910.1001) | ||
| Portland cement | 50 | |
| Graphite (Natural) | 15 | |
| Coal Dust: | ||
| Respirable fraction less than 5% SiO 2 | 2.4 mg/m 3 e | |
| 10 mg/m 3 e | ||
| Respirable fraction greater than 5% SiO 2 | _____ %SiO 2 + 2 | |
| Inert or Nuisance Dust: d | ||
| Respirable fraction | 15 | 5 mg/m 3 |
| Total dust | 50 | 15 mg/m 3 |
| Note—Conversion factors - mppcf × 35.3 = million particles per cubic meter = particles per c.c. | ||
| a Millions of particles per cubic foot of air, based on impinger samples counted by light-field techniques. | ||
| b The percentage of crystalline silica in the formula is the amount determined from airborne samples, except in those instances in which other methods have been shown to be applicable. | ||
| c Containing less than 1% quartz; if 1% quartz or more, use quartz limit. | ||
| d All inert or nuisance dusts, whether mineral, inorganic, or organic, not listed specifically by substance name are covered by this limit, which is the same as the Particulates Not Otherwise Regulated (PNOR) limit in Table Z-1. | ||
| e Both concentration and percent quartz for the application of this limit are to be determined from the fraction passing a size-selector with the following characteristics: |
| Aerodynamic diameter (unit density sphere) | Percent passing selector |
|---|---|
| 2 | 90 |
| 2.5 | 75 |
| 3.5 | 50 |
| 5.0 | 25 |
| 10 | 0 |
| The measurements under this note refer to the use of an AEC (now NRC) instrument. The respirable fraction of coal dust is determined with an MRE; the figure corresponding to that of 2.4 mg/m 3 in the table for coal dust is 4.5 mg/m 3K . | |
| f This standard applies to any operations or sectors for which the respirable crystalline silica standard, 1910.1053, is stayed or is otherwise not in effect. |
[58 FR 35340, June 30, 1993; 58 FR 40191, July 27, 1993, as amended at 61 FR 56831, Nov. 4, 1996; 62 FR 1600, Jan. 10, 1997; 62 FR 42018, Aug. 4, 1997; 71 FR 10373, Feb. 28, 2006; 71 FR 16673, Apr. 3, 2006; 71 FR 36008, June 23, 2006; 81 FR 16861, Mar. 25, 2016; 81 FR 31167, May 18, 2016; 81 FR 60272, Sept. 1, 2016; 82 FR 2735, Jan. 9, 2017]
Asbestos includes chrysotile, amosite, crocidolite, tremolite asbestos, anthophyllite asbestos, actinolite asbestos, and any of these minerals that have been chemically treated and/or altered.
Asbestos-containing material (ACM) means any material containing more than 1% asbestos.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person authorized by the employer and required by work duties to be present in regulated areas.
Building/facility owner is the legal entity, including a lessee, which exercises control over management and record keeping functions relating to a building and/or facility in which activities covered by this standard take place.
Certified industrial hygienist (CIH) means one certified in the practice of industrial hygiene by the American Board of Industrial Hygiene.
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Employee exposure means that exposure to airborne asbestos that would occur if the employee were not using respiratory protective equipment.
Fiber means a particulate form of asbestos 5 micrometers or longer,with a length-to-diameter ratio of at least 3 to 1.
High-efficiency particulate air (HEPA) filter means a filter capable of trapping and retaining at least 99.97 percent of 0.3 micrometer diameter mono-disperse particles.
Homogeneous area means an area of surfacing material or thermal system insulation that is uniform in color and texture.
Industrial hygienist means a professional qualified by education, training, and experience to anticipate, recognize, evaluate and develop controls for occupational health hazards.
PACM means “presumed asbestos containing material.”
Presumed asbestos containing material means thermal system insulation and surfacing material found in buildings constructed no later than 1980. The designation of a material as “PACM” may be rebutted pursuant to paragraph (j)(8) of this section.
Regulated area means an area established by the employer to demarcate areas where airborne concentrations of asbestos exceed, or there is a reasonable possibility they may exceed, the permissible exposure limits.
Surfacing ACM means surfacing material which contains more than 1% asbestos.
Surfacing material means material that is sprayed, troweled-on or otherwise applied to surfaces (such as acoustical plaster on ceilings and fireproofing materials on structural members, or other materials on surfaces for acoustical, fireproofing, and other purposes).
Thermal System Insulation (TSI) means ACM applied to pipes, fittings, boilers, breeching, tanks, ducts or other structural components to prevent heat loss or gain.
Thermal System Insulation ACM means thermal system insulation which contains more than 1% asbestos.
The employer shall ensure that no employee is exposed to an airborne concentration of asbestos in excess of 0.1 fiber per cubic centimeter of air as an eight (8)-hour time-weighted average (TWA) as determined by the method prescribed in appendix A to this section, or by an equivalent method.
The employer shall ensure that no employee is exposed to an airborne concentration of asbestos in excess of 1.0 fiber per cubic centimeter of air (1 f/cc) as averaged over a sampling period of thirty (30) minutes as determined by the method prescribed in appendix A to this section, or by an equivalent method.
After the initial determinations required by paragraph (d)(2)(i) of this section, samples shall be of such frequency and pattern as to represent with reasonable accuracy the levels of exposure of the employees. In no case shall sampling be at intervals greater than six months for employees whose exposures may reasonably be foreseen to exceed the TWA permissible exposure limit and/or excursion limit.
If either the initial or the periodic monitoring required by paragraphs (d)(2) and (d)(3) of this section statistically indicates that employee exposures are below the TWA permissible exposure limit and/or excursion limit, the employer may discontinue the monitoring for those employees whose exposures are represented by such monitoring.
Notwithstanding the provisions of paragraphs (d)(2)(ii) and (d)(4) of this section, the employer shall institute the exposure monitoring required under paragraphs (d)(2)(i) and (d)(3) of this section whenever there has been a change in the production, process, control equipment, personnel or work practices that may result in new or additional exposures above the TWA permissible exposure limit and/or excursion limit or when the employer has any reason to suspect that a change may result in new or additional exposures above the PEL and/or excursion limit.
The employer shall establish regulated areas wherever airborne concentrations of asbestos and/or PACM are in excess of the TWA and/or excursion limit prescribed in paragraph (c) of this section.
Regulated areas shall be demarcated from the rest of the workplace in any manner that minimizes the number of persons who will be exposed to asbestos.
Access to regulated areas shall be limited to authorized persons or to persons authorized by the Act or regulations issued pursuant thereto.
Each person entering a regulated area shall be supplied with and required to use a respirator, selected in accordance with paragraph (g)(2) of this section.
The employer shall ensure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in the regulated areas.
Local exhaust ventilation and dust collection systems shall be designed, constructed, installed, and maintained in accordance with good practices such as those found in the American National Standard Fundamentals Governing the Design and Operation of Local Exhaust Systems, ANSI Z9.2-1979.
All hand-operated and power-operated tools which would produce or release fibers of asbestos, such as, but not limited to, saws, scorers, abrasive wheels, and drills, shall be provided with local exhaust ventilation systems which comply with paragraph (f)(1)(iv) of this section.
Insofar as practicable, asbestos shall be handled, mixed, applied, removed, cut, scored, or otherwise worked in a wet state sufficient to prevent the emission of airborne fibers so as to expose employees to levels in excess of the TWA and/or excursion limit, prescribed in paragraph (c) of this section, unless the usefulness of the product would be diminished thereby.
No asbestos cement, mortar, coating, grout, plaster, or similar material containing asbestos, shall be removed from bags, cartons, or other containers in which they are shipped, without being either wetted, or enclosed, or ventilated so as to prevent effectively the release of airborne fibers.
Compressed air shall not be used to remove asbestos or materials containing asbestos unless the compressed air is used in conjunction with a ventilation system which effectively captures the dust cloud created by the compressed air.
Sanding of asbestos-containing flooring material is prohibited.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Employers must:
If an employee is exposed to asbestos above the TWA and/or excursion limit, or where the possibility of eye irritation exists, the employer shall provide at no cost to the employee and ensure that the employee uses appropriate protective work clothing and equipment such as, but not limited to:
The employer shall ensure that employees do not smoke in work areas where they are occupationally exposed to asbestos because of activities in that work area.
This section applies to the communication of information concerning asbestos hazards in general industry to facilitate compliance with this standard. Asbestos exposure in general industry occurs in a wide variety of industrial and commercial settings. Employees who manufacture asbestos-containing products may be exposed to asbestos fibers. Employees who repair and replace automotive brakes and clutches may be exposed to asbestos fibers. In addition, employees engaged in housekeeping activities in industrial facilities with asbestos product manufacturing operations, and in public and commercial buildings with installed asbestos containing materials may be exposed to asbestos fibers. Most of these workers are covered by this general industry standard, with the exception of state or local governmental employees in non-state plan states. It should be noted that employees who perform housekeeping activities during and after construction activities are covered by the asbestos construction standard, 29 CFR 1926.1101, formerly 1926.58. However, housekeeping employees, regardless of industry designation, should know whether building components they maintain may expose them to asbestos. The same hazard communication provisions will protect employees who perform housekeeping operations in all three asbestos standards; general industry, construction, and shipyard employment. As noted in the construction standard, building owners are often the only and/or best source of information concerning the presence of previously installed asbestos containing building materials. Therefore they, along with employers of potentially exposed employees, are assigned specific information conveying and retention duties under this section.
Employers and building owners are required to treat installed TSI and sprayed on and troweled-on surfacing materials as ACM in buildings constructed no later than 1980 for purposes of this standard. These materials are designated “presumed ACM or PACM”, and are defined in paragraph (b) of this section. Asphalt and vinyl flooring material installed no later than 1980 also must be treated as asbestos-containing. The employer or building owner may demonstrate that PACM and flooring material do not contain asbestos by complying with paragraph (j)(8)(iii) of this section.
Warning signs shall be provided and displayed at each regulated area. In addition, warning signs shall be posted at all approaches to regulated areas so that an employee may read the signs and take necessary protective steps before entering the area.
DANGER
ASBESTOS
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
AUTHORIZED PERSONNEL ONLY
WEAR RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING IN THIS AREA
DANGER
ASBESTOS
CANCER AND LUNG DISEASE
HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE CLOTHING ARE REQUIRED IN THIS AREA
Labels shall be affixed to all raw materials, mixtures, scrap, waste, debris, and other products containing asbestos fibers, or to their containers. When a building owner or employer identifies previously installed ACM and/or PACM, labels or signs shall be affixed or posted so that employees will be notified of what materials contain ACM and/or PACM. The employer shall attach such labels in areas where they will clearly be noticed by employees who are likely to be exposed, such as at the entrance to mechanical room/areas. Signs required by paragraph (j) of this section may be posted in lieu of labels so long as they contain the information required for labeling.
In addition to the requirements of paragraph (j)(1), the employer shall ensure that labels of bags or containers of protective clothing and equipment, scrap, waste, and debris containing asbestos fibers include the following information:
DANGER
CONTAINS ASBESTOS FIBERS
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
DO NOT BREATHE DUST
AVOID CREATING DUST
DANGER
CONTAINS ASBESTOS FIBERS
AVOID CREATING DUST
CANCER AND LUNG DISEASE HAZARD
HEPA-filtered vacuuming equipment shall be used for vacuuming asbestos containing waste and debris. The equipment shall be used and emptied in a manner which minimizes the reentry of asbestos into the workplace.
Waste, scrap, debris, bags, containers, equipment, and clothing contaminated with asbestos consigned for disposal, shall be collected, recycled and disposed of in sealed impermeable bags, or other closed, impermeable containers.
The employer shall institute a medical surveillance program for all employees who are or will be exposed to airborne concentrations of fibers of asbestos at or above the TWA and/or excursion limit.
| Years since first exposure | Age of employee | ||
|---|---|---|---|
| 15 to 35 | 35 + to 45 | 45 + | |
| 0 to 10 | Every 5 years | Every 5 years | Every 5 years. |
| 10 + | Every 5 years | Every 2 years | Every 1 year. |
No medical examination is required of any employee, if adequate records show that the employee has been examined in accordance with any of paragraphs ((l)(2) through (l)(4)) of this section within the past 1 year period. A pre- employment medical examination which was required as a condition of employment by the employer, may not be used by that employer to meet the requirements of this paragraph, unless the cost of such examination is borne by the employer.
The employer shall provide the following information to the examining physician:
The employer shall maintain all employee training records for one (1) year beyond the last date of employment of that employee.
The employer shall comply with the requirements concerning transfer of records set forth in 29 CFR 1910.1020(h).
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to asbestos conducted in accordance with paragraph (d) of this section.
When observation of the monitoring of employee exposure to asbestos requires entry into an area where the use of protective clothing or equipment is required, the observer shall be provided with and be required to use such clothing and equipment and shall comply with all other applicable safety and health procedures.
Appendix A to § 1910.1001—OSHA Reference Method—Mandatory
This mandatory appendix specifies the procedure for analyzing air samples for asbestos and specifies quality control procedures that must be implemented by laboratories performing the analysis. The sampling and analytical methods described below represent the elements of the available monitoring methods (such as appendix B of their regulation, the most current version of the OSHA method ID-160, or the most current version of the NIOSH Method 7400). All employers who are required to conduct air monitoring under paragraph (d) of the standard are required to utilize analytical laboratories that use this procedure, or an equivalent method, for collecting and analyzing samples.
Sampling and Analytical Procedure
1. The sampling medium for air samples shall be mixed cellulose ester filter membranes. These shall be designated by the manufacturer as suitable for asbestos counting. See below for rejection of blanks.
2. The preferred collection device shall be the 25-mm diameter cassette with an open-faced 50-mm electrically conductive extension cowl. The 37-mm cassette may be used if necessary but only if written justification for the need to use the 37-mm filter cassette accompanies the sample results in the employee's exposure monitoring record. Do not reuse or reload cassettes for asbestos sample collection.
3. An air flow rate between 0.5 liter/min and 2.5 liters/min shall be selected for the 25-mm cassette. If the 37-mm cassette is used, an air flow rate between 1 liter/min and 2.5 liters/min shall be selected.
4. Where possible, a sufficient air volume for each air sample shall be collected to yield between 100 and 1,300 fibers per square millimeter on the membrane filter. If a filter darkens in appearance or if loose dust is seen on the filter, a second sample shall be started.
5. Ship the samples in a rigid container with sufficient packing material to prevent dislodging the collected fibers. Packing material that has a high electrostatic charge on its surface (e.g., expanded polystyrene) cannot be used because such material can cause loss of fibers to the sides of the cassette.
6. Calibrate each personal sampling pump before and after use with a representative filter cassette installed between the pump and the calibration devices.
7. Personal samples shall be taken in the “breathing zone” of the employee ( i.e., attached to or near the collar or lapel near the worker's face).
8. Fiber counts shall be made by positive phase contrast using a microscope with an 8 to 10× eyepiece and a 40 to 45× objective for a total magnification of approximately 400× and a numerical aperture of 0.65 to 0.75. The microscope shall also be fitted with a green or blue filter.
9. The microscope shall be fitted with a Walton-Beckett eyepiece graticule calibrated for a field diameter of 100 micrometers (±2 micrometers).
10. The phase-shift detection limit of the microscope shall be about 3 degrees measured using the HSE phase shift test slide as outlined below.
a. Place the test slide on the microscope stage and center it under the phase objective.
b. Bring the blocks of grooved lines into focus.
c. If the image deteriorates, clean and adjust the microscope optics. If the problem persists, consult the microscope manufacturer.
11. Each set of samples taken will include 10% field blanks or a minimum of 2 field blanks. These blanks must come from the same lot as the filters used for sample collection. The field blank results shall be averaged and subtracted from the analytical results before reporting. A set consists of any sample or group of samples for which an evaluation for this standard must be made. Any samples represented by a field blank having a fiber count in excess of the detection limit of the method being used shall be rejected.
12. The samples shall be mounted by the acetone/triacetin method or a method with an equivalent index of refraction and similar clarity.
13. Observe the following counting rules.
a. Count only fibers equal to or longer than 5 micrometers. Measure the length of curved fibers along the curve.
b. In the absence of other information, count all particles as asbesto that have a length-to-width ratio (aspect ratio) of 3:1 or greater.
c. Fibers lying entirely within the boundary of the Walton-Beckett graticule field shall receive a count of 1. Fibers crossing the boundary once, having one end within the circle, shall receive the count of one half ( 1/2 ). Do not count any fiber that crosses the graticule boundary more than once. Reject and do not count any other fibers even though they may be visible outside the graticule area.
d. Count bundles of fibers as one fiber unless individual fibers can be identified by observing both ends of an individual fiber.
e. Count enough graticule fields to yield 100 fibers. Count a minimum of 20 fields; stop counting at 100 fields regardless of fiber count.
14. Blind recounts shall be conducted at the rate of 10 percent.
Quality Control Procedures
1. Intralaboratory program. Each laboratory and/or each company with more than one microscopist counting slides shall establish a statistically designed quality assurance program involving blind recounts and comparisons between microscopists to monitor the variability of counting by each microscopist and between microscopists. In a company with more than one laboratory, the program shall include all laboratories and shall also evaluate the laboratory-to-laboratory variability.
2.a. Interlaboratory program. Each laboratory analyzing asbestos samples for compliance determination shall implement an interlaboratory quality assurance program that as a minimum includes participation of at least two other independent laboratories. Each laboratory shall participate in round robin testing at least once every 6 months with at least all the other laboratories in its interlaboratory quality assurance group. Each laboratory shall submit slides typical of its own work load for use in this program. The round robin shall be designed and results analyzed using appropriate statistical methodology.
2.b. All laboratories should also participate in a national sample testing scheme such as the Proficiency Analytical Testing Program (PAT), or the Asbestos Registry sponsored by the American Industrial Hygiene Association (AIHA).
3. All individuals performing asbestos analysis must have taken the NIOSH course for sampling and evaluating airborne asbestos dust or an equalivalent course.
4. When the use of different microscopes contributes to differences between counters and laboratories, the effect of the different microscope shall be evaluated and the microscope shall be replaced, as necessary.
5. Current results of these quality assurance programs shall be posted in each laboratory to keep the microscopists informed.
Appendix B to § 1910.1001—Detailed Procedures for Asbestos Sampling and Analysis—Non-mandatory
| Matrix Air: | |
|---|---|
| OSHA Permissible Exposure Limits: | |
| Time Weighted Average | 0.1 fiber/cc |
| Excursion Level (30 minutes) | 1.0 fiber/cc |
| Collection Procedure: | |
| A known volume of air is drawn through a 25-mm diameter cassette containing a mixed-cellulose ester filter. The cassette must be equipped with an electrically conductive 50-mm extension cowl. The sampling time and rate are chosen to give a fiber density of between 100 to 1,300 fibers/mm 2 on the filter. | |
| Recommended Sampling Rate | 0.5 to 5.0 liters/minute (L/min) |
| Recommended Air Volumes: | |
| Minimum | 25 L |
| Maximum | 2,400 L |
Analytical Procedure: A portion of the sample filter is cleared and prepared for asbestos fiber counting by Phase Contrast Microscopy (PCM) at 400X.
Commercial manufacturers and products mentioned in this method are for descriptive use only and do not constitute endorsements by USDOL-OSHA. Similar products from other sources can be substituted.
1. Introduction
This method describes the collection of airborne asbestos fibers using calibrated sampling pumps with mixed-cellulose ester (MCE) filters and analysis by phase contrast microscopy (PCM). Some terms used are unique to this method and are defined below:
Asbestos: A term for naturally occurring fibrous minerals. Asbestos includes chrysotile, crocidolite, amosite (cummingtonite-grunerite asbestos), tremolite asbestos, actinolite asbestos, anthophyllite asbestos, and any of these minerals that have been chemically treated and/or altered. The precise chemical formulation of each species will vary with the location from which it was mined. Nominal compositions are listed:
| Chrysotile | Mg 3 Si 2 O 5 (OH) 4 |
|---|---|
| Crocidolite | Na 2 Fe 3 2 + Fe 2 3 + Si 8 O 22 (OH) 2 |
| Amosite | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
| Tremolite-actinolite | Ca 2 (Mg,Fe) 5 Si 8 O 22 (OH) 2 |
| Anthophyllite | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
Asbestos Fiber: A fiber of asbestos which meets the criteria specified below for a fiber.
Aspect Ratio: The ratio of the length of a fiber to it's diameter (e.g. 3:1, 5:1 aspect ratios).
Cleavage Fragments: Mineral particles formed by comminution of minerals, especially those characterized by parallel sides and a moderate aspect ratio (usually less than 20:1).
Detection Limit: The number of fibers necessary to be 95% certain that the result is greater than zero.
Differential Counting: The term applied to the practice of excluding certain kinds of fibers from the fiber count because they do not appear to be asbestos.
Fiber: A particle that is 5 µm or longer, with a length-to-width ratio of 3 to 1 or longer.
Field: The area within the graticule circle that is superimposed on the microscope image.
Set: The samples which are taken, submitted to the laboratory, analyzed, and for which, interim or final result reports are generated.
Tremolite, Anthophyllite, and Actinolite: The non-asbestos form of these minerals which meet the definition of a fiber. It includes any of these minerals that have been chemically treated and/or altered.
Walton-Beckett Graticule: An eyepiece graticule specifically designed for asbestos fiber counting. It consists of a circle with a projected diameter of 100 2 µm (area of about 0.00785 mm 2 ) with a crosshair having tic-marks at 3-µm intervals in one direction and 5-µm in the orthogonal direction. There are marks around the periphery of the circle to demonstrate the proper sizes and shapes of fibers. This design is reproduced in Figure 1. The disk is placed in one of the microscope eyepieces so that the design is superimposed on the field of view.
1.1. History
Early surveys to determine asbestos exposures were conducted using impinger counts of total dust with the counts expressed as million particles per cubic foot. The British Asbestos Research Council recommended filter membrane counting in 1969. In July 1969, the Bureau of Occupational Safety and Health published a filter membrane method for counting asbestos fibers in the United States. This method was refined by NIOSH and published as P CAM 239. On May 29, 1971, OSHA specified filter membrane sampling with phase contrast counting for evaluation of asbestos exposures at work sites in the United States. The use of this technique was again required by OSHA in 1986. Phase contrast microscopy has continued to be the method of choice for the measurement of occupational exposure to asbestos.
1.2. Principle
Air is drawn through a MCE filter to capture airborne asbestos fibers. A wedge shaped portion of the filter is removed, placed on a glass microscope slide and made transparent. A measured area (field) is viewed by PCM. All the fibers meeting defined criteria for asbestos are counted and considered a measure of the airborne asbestos concentration.
1.3. Advantages and Disadvantages
There are four main advantages of PCM over other methods:
Phase contrast is a fiber counting technique which excludes non-fibrous particles from the analysis.
The main disadvantage of PCM is that it does not positively identify asbestos fibers. Other fibers which are not asbestos may be included in the count unless differential counting is performed. This requires a great deal of experience to adequately differentiate asbestos from non-asbestos fibers. Positive identification of asbestos must be performed by polarized light or electron microscopy techniques. A further disadvantage of PCM is that the smallest visible fibers are about 0.2 µm in diameter while the finest asbestos fibers may be as small as 0.02 µm in diameter. For some exposures, substantially more fibers may be present than are actually counted.
1.4. Workplace Exposure
Asbestos is used by the construction industry in such products as shingles, floor tiles, asbestos cement, roofing felts, insulation and acoustical products. Non-construction uses include brakes, clutch facings, paper, paints, plastics, and fabrics. One of the most significant exposures in the workplace is the removal and encapsulation of asbestos in schools, public buildings, and homes. Many workers have the potential to be exposed to asbestos during these operations.
About 95% of the asbestos in commercial use in the United States is chrysotile. Crocidolite and amosite make up most of the remainder. Anthophyllite and tremolite or actinolite are likely to be encountered as contaminants in various industrial products.
1.5. Physical Properties
Asbestos fiber possesses a high tensile strength along its axis, is chemically inert, non-combustible, and heat resistant. It has a high electrical resistance and good sound absorbing properties. It can be weaved into cables, fabrics or other textiles, and also matted into asbestos papers, felts, or mats.
2. Range and Detection Limit
2.1. The ideal counting range on the filter is 100 to 1,300 fibers/mm 2. With a Walton-Beckett graticule this range is equivalent to 0.8 to 10 fibers/field. Using NIOSH counting statistics, a count of 0.8 fibers/field would give an approximate coefficient of variation (CV) of 0.13.
2.2. The detection limit for this method is 4.0 fibers per 100 fields or 5.5 fibers/mm 2. This was determined using an equation to estimate the maximum CV possible at a specific concentration (95% confidence) and a Lower Control Limit of zero. The CV value was then used to determine a corresponding concentration from historical CV vs fiber relationships. As an example:
Lower Control Limit (95% Confidence) = AC − 1.645(CV)(AC)
Where:
AC = Estimate of the airborne fiber concentration (fibers/cc) Setting the Lower Control Limit = 0 and solving for CV:
0 = AC − 1.645(CV)(AC)
CV = 0.61
This value was compared with CV vs. count curves. The count at which CV = 0.61 for Leidel-Busch counting statistics or for an OSHA Salt Lake Technical Center (OSHA-SLTC) CV curve (see appendix A for further information) was 4.4 fibers or 3.9 fibers per 100 fields, respectively. Although a lower detection limit of 4 fibers per 100 fields is supported by the OSHA-SLTC data, both data sets support the 4.5 fibers per 100 fields value.
3. Method Performance—Precision and Accuracy
Precision is dependent upon the total number of fibers counted and the uniformity of the fiber distribution on the filter. A general rule is to count at least 20 and not more than 100 fields. The count is discontinued when 100 fibers are counted, provided that 20 fields have already been counted. Counting more than 100 fibers results in only a small gain in precision. As the total count drops below 10 fibers, an accelerated loss of precision is noted.
At this time, there is no known method to determine the absolute accuracy of the asbestos analysis. Results of samples prepared through the Proficiency Analytical Testing (PAT) Program and analyzed by the OSHA-SLTC showed no significant bias when compared to PAT reference values. The PAT samples were analyzed from 1987 to 1989 (N = 36) and the concentration range was from 120 to 1,300 fibers/mm 2.
4. Interferences
Fibrous substances, if present, may interfere with asbestos analysis.
Some common fibers are:
fiberglass
anhydrite
plant fibers
perlite veins
gypsum
some synthetic fibers
membrane structures
sponge spicules
diatoms
microorganisms
wollastonite
The use of electron microscopy or optical tests such as polarized light, and dispersion staining may be used to differentiate these materials from asbestos when necessary.
5. Sampling
5.1. Equipment
5.1.1. Sample assembly (The assembly is shown in Figure 3). Conductive filter holder consisting of a 25-mm diameter, 3-piece cassette having a 50-mm long electrically conductive extension cowl. Backup pad, 25-mm, cellulose. Membrane filter, mixed-cellulose ester (MCE), 25-mm, plain, white, 0.4 to 1.2-µm pore size.
5.1.2. Gel bands for sealing cassettes.
5.1.3. Sampling pump.
Each pump must be a battery operated, self-contained unit small enough to be placed on the monitored employee and not interfere with the work being performed. The pump must be capable of sampling at the collection rate for the required sampling time.
5.1.4. Flexible tubing, 6-mm bore.
5.1.5. Pump calibration.
Stopwatch and bubble tube/burette or electronic meter.
5.2. Sampling Procedure
5.2.1. Seal the point where the base and cowl of each cassette meet with a gel band or tape.
5.2.2. Charge the pumps completely before beginning.
5.2.3. Connect each pump to a calibration cassette with an appropriate length of 6-mm bore plastic tubing. Do not use luer connectors—the type of cassette specified above has built-in adapters.
5.2.4. Select an appropriate flow rate for the situation being monitored. The sampling flow rate must be between 0.5 and 5.0 L/min for personal sampling and is commonly set between 1 and 2 L/min. Always choose a flow rate that will not produce overloaded filters.
5.2.5. Calibrate each sampling pump before and after sampling with a calibration cassette in-line (Note: This calibration cassette should be from the same lot of cassettes used for sampling). Use a primary standard (e.g. bubble burette) to calibrate each pump. If possible, calibrate at the sampling site.
5.2.6. Connect each pump to the base of each sampling cassette with flexible tubing. Remove the end cap of each cassette and take each air sample open face. Assure that each sample cassette is held open side down in the employee's breathing zone during sampling. The distance from the nose/mouth of the employee to the cassette should be about 10 cm. Secure the cassette on the collar or lapel of the employee using spring clips or other similar devices.
5.2.7. A suggested minimum air volume when sampling to determine TWA compliance is 25 L. For Excursion Limit (30 min sampling time) evaluations, a minimum air volume of 48 L is recommended.
5.2.8. The most significant problem when sampling for asbestos is overloading the filter with non-asbestos dust. Suggested maximum air sample volumes for specific environments are:
| Environment | Air vol. (L) |
|---|---|
| Asbestos removal operations (visible dust) | 100 |
| Asbestos removal operations (little dust) | 240 |
| Office environments | 400 to 2,400 |
Caution: Do not overload the filter with dust. High levels of non-fibrous dust particles may obscure fibers on the filter and lower the count or make counting impossible. If more than about 25 to 30% of the field area is obscured with dust, the result may be biased low. Smaller air volumes may be necessary when there is excessive non-asbestos dust in the air.
While sampling, observe the filter with a small flashlight. If there is a visible layer of dust on the filter, stop sampling, remove and seal the cassette, and replace with a new sampling assembly. The total dust loading should not exceed 1 mg.
5.2.9. Blank samples are used to determine if any contamination has occurred during sample handling. Prepare two blanks for the first 1 to 20 samples. For sets containing greater than 20 samples, prepare blanks as 10% of the samples. Handle blank samples in the same manner as air samples with one exception: Do not draw any air through the blank samples. Open the blank cassette in the place where the sample cassettes are mounted on the employee. Hold it open for about 30 seconds. Close and seal the cassette appropriately. Store blanks for shipment with the sample cassettes.
5.2.10. Immediately after sampling, close and seal each cassette with the base and plastic plugs. Do not touch or puncture the filter membrane as this will invalidate the analysis.
5.2.11 Attach and secure a sample seal around each sample cassette in such a way as to assure that the end cap and base plugs cannot be removed without destroying the seal. Tape the ends of the seal together since the seal is not long enough to be wrapped end-to-end. Also wrap tape around the cassette at each joint to keep the seal secure.
5.3. Sample Shipment
5.3.1. Send the samples to the laboratory with paperwork requesting asbestos analysis. List any known fibrous interferences present during sampling on the paperwork. Also, note the workplace operation(s) sampled.
5.3.2. Secure and handle the samples in such that they will not rattle during shipment nor be exposed to static electricity. Do not ship samples in expanded polystyrene peanuts, vermiculite, paper shreds, or excelsior. Tape sample cassettes to sheet bubbles and place in a container that will cushion the samples in such a manner that they will not rattle.
5.3.3. To avoid the possibility of sample contamination, always ship bulk samples in separate mailing containers.
6. Analysis
6.1. Safety Precautions
6.1.1. Acetone is extremely flammable and precautions must be taken not to ignite it. Avoid using large containers or quantities of acetone. Transfer the solvent in a ventilated laboratory hood. Do not use acetone near any open flame. For generation of acetone vapor, use a spark free heat source.
6.1.2. Any asbestos spills should be cleaned up immediately to prevent dispersal of fibers. Prudence should be exercised to avoid contamination of laboratory facilities or exposure of personnel to asbestos. Asbestos spills should be cleaned up with wet methods and/or a High Efficiency Particulate-Air (HEPA) filtered vacuum.
Caution: Do not use a vacuum without a HEPA filter—It will disperse fine asbestos fibers in the air.
6.2. Equipment
6.2.1. Phase contrast microscope with binocular or trinocular head.
6.2.2. Widefield or Huygenian 10X eyepieces ( Note: The eyepiece containing the graticule must be a focusing eyepiece. Use a 40X phase objective with a numerical aperture of 0.65 to 0.75).
6.2.3. Kohler illumination (if possible) with green or blue filter.
6.2.4. Walton-Beckett Graticule, type G-22 with 100 ±2 µm projected diameter.
6.2.5. Mechanical stage.
A rotating mechanical stage is convenient for use with polarized light.
6.2.6. Phase telescope.
6.2.7. Stage micrometer with 0.01-mm subdivisions.
6.2.8. Phase-shift test slide, mark II (Available from PTR optics Ltd., and also McCrone).
6.2.9. Precleaned glass slides, 25 mm × 75 mm. One end can be frosted for convenience in writing sample numbers, etc., or paste-on labels can be used.
6.2.10. Cover glass #1 1/2.
6.2.11. Scalpel (#10, curved blade).
6.2.12. Fine tipped forceps.
6.2.13. Aluminum block for clearing filter (see appendix D and Figure 4).
6.2.14. Automatic adjustable pipette, 100- to 500-µL.
6.2.15. Micropipette, 5 µL.
6.3. Reagents
6.3.1. Acetone (HPLC grade).
6.3.2. Triacetin (glycerol triacetate).
6.3.3. Lacquer or nail polish.
6.4. Standard Preparation
A way to prepare standard asbestos samples of known concentration has not been developed. It is possible to prepare replicate samples of nearly equal concentration. This has been performed through the PAT program. These asbestos samples are distributed by the AIHA to participating laboratories.
Since only about one-fourth of a 25-mm sample membrane is required for an asbestos count, any PAT sample can serve as a “standard” for replicate counting.
6.5. Sample Mounting
An aluminum block or similar device is required for sample preparation.
6.5.1. Heat the aluminum block to about 70 °C. The hot block should not be used on any surface that can be damaged by either the heat or from exposure to acetone.
6.5.2. Ensure that the glass slides and cover glasses are free of dust and fibers.
6.5.3. Remove the top plug to prevent a vacuum when the cassette is opened. Clean the outside of the cassette if necessary. Cut the seal and/or tape on the cassette with a razor blade. Very carefully separate the base from the extension cowl, leaving the filter and backup pad in the base.
6.5.4. With a rocking motion cut a triangular wedge from the filter using the scalpel. This wedge should be one-sixth to one-fourth of the filter. Grasp the filter wedge with the forceps on the perimeter of the filter which was clamped between the cassette pieces. DO NOT TOUCH the filter with your finger. Place the filter on the glass slide sample side up. Static electricity will usually keep the filter on the slide until it is cleared.
6.5.5. Place the tip of the micropipette containing about 200 µL acetone into the aluminum block. Insert the glass slide into the receiving slot in the aluminum block. Inject the acetone into the block with slow, steady pressure on the plunger while holding the pipette firmly in place. Wait 3 to 5 seconds for the filter to clear, then remove the pipette and slide from the aluminum block.
6.5.6. Immediately (less than 30 seconds) place 2.5 to 3.5 µL of triacetin on the filter (Note: Waiting longer than 30 seconds will result in increased index of refraction and decreased contrast between the fibers and the preparation. This may also lead to separation of the cover slip from the slide).
6.5.7. Lower a cover slip gently onto the filter at a slight angle to reduce the possibility of forming air bubbles. If more than 30 seconds have elapsed between acetone exposure and triacetin application, glue the edges of the cover slip to the slide with lacquer or nail polish.
6.5.8. If clearing is slow, warm the slide for 15 min on a hot plate having a surface temperature of about 50 °C to hasten clearing. The top of the hot block can be used if the slide is not heated too long.
6.5.9. Counting may proceed immediately after clearing and mounting are completed.
6.6. Sample Analysis
Completely align the microscope according to the manufacturer's instructions. Then, align the microscope using the following general alignment routine at the beginning of every counting session and more often if necessary.
6.6.1. Alignment
Even a small amount of dirt can significantly degrade the image.
6.6.2. Counting Fibers
6.7. Fiber Identification
As previously mentioned in Section 1.3., PCM does not provide positive confirmation of asbestos fibers. Alternate differential counting techniques should be used if discrimination is desirable. Differential counting may include primary discrimination based on morphology, polarized light analysis of fibers, or modification of PCM data by Scanning Electron or Transmission Electron Microscopy.
A great deal of experience is required to routinely and correctly perform differential counting. It is discouraged unless it is legally necessary. Then, only if a fiber is obviously not asbestos should it be excluded from the count. Further discussion of this technique can be found in reference 8.10.
If there is a question whether a fiber is asbestos or not, follow the rule:
“WHEN IN DOUBT, COUNT.”
6.8. Analytical Recommendations—Quality Control System
6.8.1. All individuals performing asbestos analysis must have taken the NIOSH course for sampling and evaluating airborne asbestos or an equivalent course.
6.8.2. Each laboratory engaged in asbestos counting shall set up a slide trading arrangement with at least two other laboratories in order to compare performance and eliminate inbreeding of error. The slide exchange occurs at least semiannually. The round robin results shall be posted where all analysts can view individual analyst's results.
6.8.3. Each laboratory engaged in asbestos counting shall participate in the Proficiency Analytical Testing Program, the Asbestos Analyst Registry or equivalent.
6.8.4. Each analyst shall select and count prepared slides from a “slide bank”. These are quality assurance counts. The slide bank shall be prepared using uniformly distributed samples taken from the workload. Fiber densities should cover the entire range routinely analyzed by the laboratory. These slides are counted blind by all counters to establish an original standard deviation. This historical distribution is compared with the quality assurance counts. A counter must have 95% of all quality control samples counted within three standard deviations of the historical mean. This count is then integrated into a new historical mean and standard deviation for the slide.
The analyses done by the counters to establish the slide bank may be used for an interim quality control program if the data are treated in a proper statistical fashion.
7. Calculations
7.1. Calculate the estimated airborne asbestos fiber concentration on the filter sample using the following formula:
where:
AC = Airborne fiber concentration
FB = Total number of fibers greater than 5 µm counted
FL = Total number of fields counted on the filter
BFB = Total number of fibers greater than 5 µm counted in the blank
BFL = Total number of fields counted on the blank
2
FR = Pump flow rate (L/min)
2
2
T = Sample collection time (min)
1,000 = Conversion of L to cc
2
7.2. Short-cut Calculation
Since a given analyst always has the same interpupillary distance, the number of fields per filter for a particular analyst will remain constant for a given size filter. The field size for that analyst is constant ( i.e., the analyst is using an assigned microscope and is not changing the reticle).
For example, if the exposed area of the filter is always 385 mm 2 and the size of the field is always 0.00785 mm 2, the number of fields per filter will always be 49,000. In addition it is necessary to convert liters of air to cc. These three constants can then be combined such that ECA/(1,000 × MFA) = 49. The previous equation simplifies to:
7.3. Recount Calculations
As mentioned in step 13 of Section 6.6.2., a “blind recount” of 10% of the slides is performed. In all cases, differences will be observed between the first and second counts of the same filter wedge. Most of these differences will be due to chance alone, that is, due to the random variability (precision) of the count method. Statistical recount criteria enables one to decide whether observed differences can be explained due to chance alone or are probably due to systematic differences between analysts, microscopes, or other biasing factors.
The following recount criterion is for a pair of counts that estimate AC in fibers/cc. The criterion is given at the type-I error level. That is, there is 5% maximum risk that we will reject a pair of counts for the reason that one might be biased, when the large observed difference is really due to chance.
Reject a pair of counts if:
Where:
AC1 = lower estimated airborne fiber concentration
AC2 = higher estimated airborne fiber concentration
ACavg = average of the two concentration estimates
FB
If a pair of counts are rejected by this criterion then, recount the rest of the filters in the submitted set. Apply the test and reject any other pairs failing the test. Rejection shall include a memo to the industrial hygienist stating that the sample failed a statistical test for homogeneity and the true air concentration may be significantly different than the reported value.
7.4. Reporting Results
Report results to the industrial hygienist as fibers/cc. Use two significant figures. If multiple analyses are performed on a sample, an average of the results is to be reported unless any of the results can be rejected for cause.
8. References
8.1. Dreesen, W.C., et al, U.S. Public Health Service: A Study of Asbestosis in the Asbestos Textile Industry, (Public Health Bulletin No. 241), US Treasury Dept., Washington, DC, 1938.
8.2. Asbestos Research Council: The Measurement of Airborne Asbestos Dust by the Membrane Filter Method (Technical Note), Asbestos Research Council, Rockdale, Lancashire, Great Britain, 1969.
8.3. Bayer, S.G., Zumwalde, R.D., Brown, T.A., Equipment and Procedure for Mounting Millipore Filters and Counting Asbestos Fibers by Phase Contrast Microscopy, Bureau of Occupational Health, U.S. Dept. of Health, Education and Welfare, Cincinnati, OH, 1969.
8.4. NIOSH Manual of Analytical Methods, 2nd ed., Vol. 1 (DHEW/NIOSH Pub. No. 77-157-A). National Institute for Occupational Safety and Health, Cincinnati, OH, 1977. pp. 239-1-239-21.
8.5. Asbestos, Code of Federal Regulations 29 CFR 1910.1001. 1971.
8.6. Occupational Exposure to Asbestos, Tremolite, Anthophyllite, and Actinolite. Final Rule, Federal Register 51:119 (20 June 1986). pp.22612-22790.
8.7. Asbestos, Tremolite, Anthophyllite, and Actinolite, Code of Federal Regulations 1910.1001. 1988. pp 711-752.
8.8. Criteria for a Recommended Standard—Occupational Exposure to Asbestos (DHEW/NIOSH Pub. No. HSM 72-10267), National Institute for Occupational Safety and Health NIOSH, Cincinnati,OH, 1972. pp. III-1-III-24.
8.9. Leidel, N.A., Bayer,S.G., Zumwalde, R.D.,Busch, K.A., USPHS/NIOSH Membrane Filter Method for Evaluating Airborne Asbestos Fibers (DHEW/NIOSH Pub. No. 79-127). National Institute for Occupational Safety and Health, Cincinnati, OH, 1979.
8.10. Dixon, W.C., Applications of Optical Microscopy in Analysis of Asbestos and Quartz, Analytical Techniques in Occupational Health Chemistry, edited by D.D. Dollberg and A.W. Verstuyft. Wash. DC: American Chemical Society, (ACS Symposium Series 120) 1980. pp. 13-41.
Quality Control
The OSHA asbestos regulations require each laboratory to establish a quality control program. The following is presented as an example of how the OSHA-SLTC constructed its internal CV curve as part of meeting this requirement. Data is from 395 samples collected during OSHA compliance inspections and analyzed from October 1980 through April 1986.
Each sample was counted by 2 to 5 different counters independently of one another. The standard deviation and the CV statistic was calculated for each sample. This data was then plotted on a graph of CV vs. fibers/mm 2. A least squares regression was performed using the following equation:
10
10
2
10
where:
2
Application of least squares gave:
A = 0.182205
B = −0.973343
C = 0.327499
Using these values, the equation becomes:
10
10
2
10
Sampling Pump Flow Rate Corrections
This correction is used if a difference greater than 5% in ambient temperature and/or pressure is noted between calibration and sampling sites and the pump does not compensate for the differences.
Where:
act
cal
cal
act
act
cal
Walton-Beckett Graticule
When ordering the Graticule for asbestos counting, specify the exact disc diameter needed to fit the ocular of the microscope and the diameter (mm) of the circular counting area. Instructions for measuring the dimensions necessary are listed:
Calculate the circle diameter, d c (mm), for the Walton-Beckett graticule and specify the diameter when making a purchase:
Example: If PL = 108 µm, AL = 2.93 mm and D = 100 µm, then,
2
If D = 100 µm = 0.1 mm, then
2
2
The Graticule is available from: Graticules Ltd., Morley Road, Tonbridge TN9 IRN, Kent, England (Telephone 011-44-732-359061). Also available from PTR Optics Ltd., 145 Newton Street, Waltham, MA 02154 [telephone (617) 891-6000] or McCrone Accessories and Components, 2506 S. Michigan Ave., Chicago, IL 60616 [phone (312)-842-7100]. The graticule is custom made for each microscope.
Appendix E to § 1910.1001—Classification of Chest X-Rays—Mandatory
Appendix F to § 1910.1001—Work Practices and Engineering Controls for Automotive Brake and Clutch Inspection, Disassembly, Repair and Assembly—Mandatory
This mandatory appendix specifies engineering controls and work practices that must be implemented by the employer during automotive brake and clutch inspection, disassembly, repair, and assembly operations. Proper use of these engineering controls and work practices by trained employees will reduce employees' asbestos exposure below the permissible exposure level during clutch and brake inspection, disassembly, repair, and assembly operations. The employer shall institute engineering controls and work practices using either the method set forth in paragraph [A] or paragraph [B] of this appendix, or any other method which the employer can demonstrate to be equivalent in terms of reducing employee exposure to asbestos as defined and which meets the requirements described in paragraph [C] of this appendix, for those facilities in which no more than 5 pairs of brakes or 5 clutches are inspected, disassembled, reassembled and/or repaired per week, the method set forth in paragraph [D] of this appendix may be used:
[A] Negative Pressure Enclosure/HEPA Vacuum System Method
[B] Low Pressure/Wet Cleaning Method
[C] Equivalent Methods
An equivalent method is one which has sufficient written detail so that it can be reproduced and has been demonstrated that the exposures resulting from the equivalent method are equal to or less than the exposures which would result from the use of the method described in paragraph [A] of this appendix. For purposes of making this comparison, the employer shall assume that exposures resulting from the use of the method described in paragraph [A] of this appendix shall not exceed 0.016 f/cc, as measured by the OSHA reference method and as averaged over at least 18 personal samples.
[D] Wet Method.
Appendix G to § 1910.1001—Substance Technical Information for Asbestos—Non-Mandatory
I. Substance Identification
A. Substance: “Asbestos” is the name of a class of magnesium-silicate minerals that occur in fibrous form. Minerals that are included in this group are chrysotile, crocidolite, amosite, tremolite asbestos, anthophyllite asbestos, and actinolite asbestos.
B. Asbestos is used in the manufacture of heat-resistant clothing, automative brake and clutch linings, and a variety of building materials including floor tiles, roofing felts, ceiling tiles, asbestos-cement pipe and sheet, and fire-resistant drywall. Asbestos is also present in pipe and boiler insulation materials, and in sprayed-on materials located on beams, in crawlspaces, and between walls.
C. The potential for a product containing asbestos to release breatheable fibers depends on its degree of friability. Friable means that the material can be crumbled with hand pressure and is therefore likely to emit fibers. The fibrous or fluffy sprayed-on materials used for fireproofing, insulation, or sound proofing are considered to be friable, and they readily release airborne fibers if disturbed. Materials such as vinyl-asbestos floor tile or roofing felts are considered nonfriable and generally do not emit airborne fibers unless subjected to sanding or sawing operations. Asbestos-cement pipe or sheet can emit airborne fibers if the materials are cut or sawed, or if they are broken during demolition operations.
D. Permissible exposure: Exposure to airborne asbestos fibers may not exceed 0.2 fibers per cubic centimeter of air (0.1 f/cc) averaged over the 8-hour workday.
II. Health Hazard Data
A. Asbestos can cause disabling respiratory disease and various types of cancers if the fibers are inhaled. Inhaling or ingesting fibers from contaminated clothing or skin can also result in these diseases. The symptoms of these diseases generally do not appear for 20 or more years after initial exposure.
B. Exposure to asbestos has been shown to cause lung cancer, mesothelioma, and cancer of the stomach and colon. Mesothelioma is a rare cancer of the thin membrane lining of the chest and abdomen. Symptoms of mesothelioma include shortness of breath, pain in the walls of the chest, and/or abdominal pain.
III. Respirators and Protective Clothing
A. Respirators: You are required to wear a respirator when performing tasks that result in asbestos exposure that exceeds the permissible exposure limit (PEL) of 0.1 f/cc. These conditions can occur while your employer is in the process of installing engineering controls to reduce asbestos exposure, or where engineering controls are not feasible to reduce asbestos exposure. Air-purifying respirators equipped with a high-efficiency particulate air (HEPA) filter can be used where airborne asbestos fiber concentrations do not exceed 2 f/cc; otherwise, air-supplied, positive-pressure, full facepiece respirators must be used. Disposable respirators or dust masks are not permitted to be used for asbestos work. For effective protection, respirators must fit your face and head snugly. Your employer is required to conduct fit tests when you are first assigned a respirator and every 6 months thereafter. Respirators should not be loosened or removed in work situations where their use is required.
B. Protective clothing: You are required to wear protective clothing in work areas where asbestos fiber concentrations exceed the permissible exposure limit.
IV. Disposal Procedures and Cleanup
A. Wastes that are generated by processes where asbestos is present include:
1. Empty asbestos shipping containers.
2. Process wastes such as cuttings, trimmings, or reject material.
3. Housekeeping waste from sweeping or vacuuming.
4. Asbestos fireproofing or insulating material that is removed from buildings.
5. Building products that contain asbestos removed during building renovation or demolition.
6. Contaminated disposable protective clothing.
B. Empty shipping bags can be flattened under exhaust hoods and packed into airtight containers for disposal. Empty shipping drums are difficult to clean and should be sealed.
C. Vacuum bags or disposable paper filters should not be cleaned, but should be sprayed with a fine water mist and placed into a labeled waste container.
D. Process waste and housekeeping waste should be wetted with water or a mixture of water and surfactant prior to packaging in disposable containers.
E. Material containing asbestos that is removed from buildings must be disposed of in leak-tight 6-mil thick plastic bags, plastic-lined cardboard containers, or plastic-lined metal containers. These wastes, which are removed while wet, should be sealed in containers before they dry out to minimize the release of asbestos fibers during handling.
V. Access to Information
A. Each year, your employer is required to inform you of the information contained in this standard and appendices for asbestos. In addition, your employer must instruct you in the proper work practices for handling materials containing asbestos, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being exposed to asbestos. You or your representative has the right to observe employee measurements and to record the results obtained. Your employer is required to inform you of your exposure, and, if you are exposed above the permissible limit, he or she is required to inform you of the actions that are being taken to reduce your exposure to within the permissible limit.
C. Your employer is required to keep records of your exposures and medical examinations. These exposure records must be kept for at least thirty (30) years. Medical records must be kept for the period of your employment plus thirty (30) years.
D. Your employer is required to release your exposure and medical records to your physician or designated representative upon your written request.
Appendix H to § 1910.1001—Medical Surveillance Guidelines for Asbestos Non-Mandatory
I. Route of Entry Inhalation, Ingestion
II. Toxicology
Clinical evidence of the adverse effects associated with exposure to asbestos is present in the form of several well-conducted epidemiological studies of occupationally exposed workers, family contacts of workers, and persons living near asbestos mines. These studies have shown a definite association between exposure to asbestos and an increased incidence of lung cancer, pleural and peritoneal mesothelioma, gastrointestinal cancer, and asbestosis. The latter is a disabling fibrotic lung disease that is caused only by exposure to asbestos. Exposure to asbestos has also been associated with an increased incidence of esophageal, kidney, laryngeal, pharyngeal, and buccal cavity cancers. As with other known chronic occupational diseases, disease associated with asbestos generally appears about 20 years following the first occurrence of exposure: There are no known acute effects associated with exposure to asbestos.
Epidemiological studies indicate that the risk of lung cancer among exposed workers who smoke cigarettes is greatly increased over the risk of lung cancer among non-exposed smokers or exposed nonsmokers. These studies suggest that cessation of smoking will reduce the risk of lung cancer for a person exposed to asbestos but will not reduce it to the same level of risk as that existing for an exposed worker who has never smoked.
III. Signs and Symptoms of Exposure-Related Disease
The signs and symptoms of lung cancer or gastrointestinal cancer induced by exposure to asbestos are not unique, except that a chest X-ray of an exposed patient with lung cancer may show pleural plaques, pleural calcification, or pleural fibrosis, and may also show asbestosis ( i.e., small irregular parenchymal opacities). Symptoms characteristic of mesothelioma include shortness of breath, pain in the chest or abdominal pain. Mesothelioma has a much longer average latency period compared with lung cancer (40 years versus 15-20 years), and mesothelioma is therefore more likely to be found among workers who were first exposed to asbestos at an early age. Mesothelioma is a fatal disease.
Asbestosis is pulmonary fibrosis caused by the accumulation of asbestos fibers in the lungs. Symptoms include shortness of breath, coughing, fatigue, and vague feelings of sickness. When the fibrosis worsens, shortness of breath occurs even at rest. The diagnosis of asbestosis is most commonly based on a history of exposure to asbestos, the presence of characteristic radiologic abnormalities, end-inspiratory crackles (rales), and other clinical features of fibrosing lung disease. Pleural plaques and thickening may be observed on chest X-rays. Asbestosis is often a progressive disease even in the absence of continued exposure, although this appears to be a highly individualized characteristic. In severe cases, death may be caused by respiratory or cardiac failure.
IV. Surveillance and Preventive Considerations
As noted in section III of this appendix, exposure to asbestos has been linked to an increased risk of lung cancer, mesothelioma, gastrointestinal cancer, and asbestosis among occupationally exposed workers. Adequate screening tests to determine an employee's potential for developing serious chronic diseases, such as cancer, from exposure to asbestos do not presently exist. However, some tests, particularly chest X-rays and pulmonary function tests, may indicate that an employee has been overexposed to asbestos increasing his or her risk of developing exposure-related chronic diseases. It is important for the physician to become familiar with the operating conditions in which occupational exposure to asbestos is likely to occur. This is particularly important in evaluating medical and work histories and in conducting physical examinations. When an active employee has been identified as having been overexposed to asbestos, measures taken by the employer to eliminate or mitigate further exposure should also lower the risk of serious long-term consequences.
The employer is required to institute a medical surveillance program for all employees who are or will be exposed to asbestos at or above the permissible exposure limit (0.1 fiber per cubic centimeter of air). All examinations and procedures must be performed by or under the supervision of a licensed physician, at a reasonable time and place, and at no cost to the employee.
Although broad latitude is given to the physician in prescribing specific tests to be included in the medical surveillance program, OSHA requires inclusion of the following elements in the routine examination:
The employer is required to make the prescribed tests available at least annually to those employees covered; more often than specified if recommended by the examining physician; and upon termination of employment.
The employer is required to provide the physician with the following information: A copy of the standard in this section (including all appendices to this section); a description of the employee's duties as they relate to asbestos exposure; the employee's representative level of exposure to asbestos; a description of any personal protective and respiratory equipment used; and information from previous medical examinations of the affected employee that is not otherwise available to the physician. Making this information available to the physician will aid in the evaluation of the employee's health in relation to assigned duties and fitness to wear personal protective equipment, if required.
The employer is required to obtain a written opinion from the examining physician containing the results of the medical examination; the physician's opinion as to whether the employee has any detected medical conditions that would place the employee at an increased risk of exposure-related disease; any recommended limitations on the employee or on the use of personal protective equipment; and a statement that the employee has been informed by the physician of the results of the medical examination and of any medical conditions related to asbestos exposure that require further explanation or treatment. This written opinion must not reveal specific findings or diagnoses unrelated to exposure to asbestos, and a copy of the opinion must be provided to the affected employee.
Appendix I to § 1910.1001—Smoking Cessation Program Information For Asbestos—Non-Mandatory
The following organizations provide smoking cessation information and program material.
1. The National Cancer Institute operates a toll-free Cancer Information Service (CIS) with trained personnel to help you. Call 1-800-4-CANCER* to reach the CIS office serving your area, or write: Office of Cancer Communications, National Cancer Institute, National Institutes of Health, Building 31, Room 10A24, Bethesda, Maryland 20892.
2. American Cancer Society, 3340 Peachtree Road, NE., Atlanta, Georgia 30062, (404) 320-3333.
The American Cancer Society (ACS) is a voluntary organization composed of 58 divisions and 3,100 local units. Through “The Great American Smokeout” in November, the annual Cancer Crusade in April, and numerous educational materials, ACS helps people learn about the health hazards of smoking and become successful ex-smokers.
3. American Heart Association, 7320 Greenville Avenue, Dallas, Texas 75231, (214) 750-5300.
The American Heart Association (AHA) is a voluntary organization with 130,000 members (physicians, scientists, and laypersons) in 55 state and regional groups. AHA produces a variety of publications and audiovisual materials about the effects of smoking on the heart. AHA also has developed a guidebook for incorporating a weight-control component into smoking cessation programs.
4. American Lung Association, 1740 Broadway, New York, New York 10019, (212) 245-8000.
A voluntary organization of 7,500 members (physicians, nurses, and laypersons), the American Lung Association (ALA) conducts numerous public information programs about the health effect of smoking. ALA has 59 state and 85 local units. The organization actively supports legislation and information campaigns for non-smokers' rights and provides help for smokers who want to quit, for example, through “Freedom From Smoking,” a self-help smoking cessation program.
5. Office on Smoking and Health, U.S. Department of Health and, Human Services, 5600 Fishers Lane, Park Building, Room 110, Rockville, Maryland 20857.
The Office on Smoking and Health (OSH) is the Department of Health and Human Services' lead agency in smoking control. OSH has sponsored distribution of publications on smoking-realted topics, such as free flyers on relapse after initial quitting, helping a friend or family member quit smoking, the health hazards of smoking, and the effects of parental smoking on teenagers.
*In Hawaii, on Oahu call 524-1234 (call collect from neighboring islands),
Spanish-speaking staff members are available during daytime hours to callers from the following areas: California, Florida, Georgia, Illinois, New Jersey (area code 210), New York, and Texas. Consult your local telephone directory for listings of local chapters.
Appendix J to § 1910.1001—Polarized Light Microscopy of Asbestos—Non-Mandatory
Method number: ID-191
Matrix: Bulk
Collection Procedure
Collect approximately 1 to 2 grams of each type of material and place into separate 20 mL scintillation vials.
Analytical Procedure
A portion of each separate phase is analyzed by gross examination, phase-polar examination, and central stop dispersion microscopy.
Commercial manufacturers and products mentioned in this method are for descriptive use only and do not constitute endorsements by USDOL-OSHA. Similar products from other sources may be substituted.
1. Introduction
This method describes the collection and analysis of asbestos bulk materials by light microscopy techniques including phase- polar illumination and central-stop dispersion microscopy. Some terms unique to asbestos analysis are defined below:
Amphibole: A family of minerals whose crystals are formed by long, thin units which have two thin ribbons of double chain silicate with a brucite ribbon in between. The shape of each unit is similar to an “I beam”. Minerals important in asbestos analysis include cummingtonite-grunerite, crocidolite, tremolite-actinolite and anthophyllite.
Asbestos: A term for naturally occurring fibrous minerals. Asbestos includes chrysotile, cummingtonite-grunerite asbestos (amosite), anthophyllite asbestos, tremolite asbestos, crocidolite, actinolite asbestos and any of these minerals which have been chemically treated or altered. The precise chemical formulation of each species varies with the location from which it was mined. Nominal compositions are listed:
| Chrysotile | Mg 3 Si 2 O 5 (OH) 4 |
|---|---|
| Crocidolite (Riebeckite asbestos) | Na 2 Fe 3 2 + Fe 2 3 + Si 8 O 22 (OH) 2 |
| Cummingtonite-Grunerite asbestos (Amosite) | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
| Tremolite-Actinolite asbestos | Ca 2 (Mg,Fe) 5 Si 8 O 22 (OH) 2 |
| Anthophyllite asbestos | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
Asbestos Fiber: A fiber of asbestos meeting the criteria for a fiber. (See section 3.5.)
Aspect Ratio: The ratio of the length of a fiber to its diameter usually defined as “length : width”, e.g. 3:1.
Brucite: A sheet mineral with the composition Mg(OH) 2.
Central Stop Dispersion Staining (microscope): This is a dark field microscope technique that images particles using only light refracted by the particle, excluding light that travels through the particle unrefracted. This is usually accomplished with a McCrone objective or other arrangement which places a circular stop with apparent aperture equal to the objective aperture in the back focal plane of the microscope.
Cleavage Fragments: Mineral particles formed by the comminution of minerals, especially those characterized by relatively parallel sides and moderate aspect ratio.
Differential Counting: The term applied to the practice of excluding certain kinds of fibers from a phase contrast asbestos count because they are not asbestos.
Fiber: A particle longer than or equal to 5 µm with a length to width ratio greater than or equal to 3:1. This may include cleavage fragments. (see section 3.5 of this appendix).
Phase Contrast: Contrast obtained in the microscope by causing light scattered by small particles to destructively interfere with unscattered light, thereby enhancing the visibility of very small particles and particles with very low intrinsic contrast.
Phase Contrast Microscope: A microscope configured with a phase mask pair to create phase contrast. The technique which uses this is called Phase Contrast Microscopy (PCM).
Phase-Polar Analysis: This is the use of polarized light in a phase contrast microscope. It is used to see the same size fibers that are visible in air filter analysis. Although fibers finer than 1 µm are visible, analysis of these is inferred from analysis of larger bundles that are usually present.
Phase-Polar Microscope: The phase-polar microscope is a phase contrast microscope which has an analyzer, a polarizer, a first order red plate and a rotating phase condenser all in place so that the polarized light image is enhanced by phase contrast.
Sealing Encapsulant: This is a product which can be applied, preferably by spraying, onto an asbestos surface which will seal the surface so that fibers cannot be released.
Serpentine: A mineral family consisting of minerals with the general composition Mg 3 (Si2O 5 (OH) 4 having the magnesium in brucite layer over a silicate layer. Minerals important in asbestos analysis included in this family are chrysotile, lizardite, antigorite.
1.1. History
Light microscopy has been used for well over 100 years for the determination of mineral species. This analysis is carried out using specialized polarizing microscopes as well as bright field microscopes. The identification of minerals is an on-going process with many new minerals described each year. The first recorded use of asbestos was in Finland about 2500 B.C. where the material was used in the mud wattle for the wooden huts the people lived in as well as strengthening for pottery. Adverse health aspects of the mineral were noted nearly 2000 years ago when Pliny the Younger wrote about the poor health of slaves in the asbestos mines. Although known to be injurious for centuries, the first modern references to its toxicity were by the British Labor Inspectorate when it banned asbestos dust from the workplace in 1898. Asbestosis cases were described in the literature after the turn of the century. Cancer was first suspected in the mid 1930's and a causal link to mesothelioma was made in 1965. Because of the public concern for worker and public safety with the use of this material, several different types of analysis were applied to the determination of asbestos content. Light microscopy requires a great deal of experience and craft. Attempts were made to apply less subjective methods to the analysis. X-ray diffraction was partially successful in determining the mineral types but was unable to separate out the fibrous portions from the non-fibrous portions. Also, the minimum detection limit for asbestos analysis by X-ray diffraction (XRD) is about 1%. Differential Thermal Analysis (DTA) was no more successful. These provide useful corroborating information when the presence of asbestos has been shown by microscopy; however, neither can determine the difference between fibrous and non-fibrous minerals when both habits are present. The same is true of Infrared Absorption (IR).
When electron microscopy was applied to asbestos analysis, hundreds of fibers were discovered present too small to be visible in any light microscope. There are two different types of electron microscope used for asbestos analysis: Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). Scanning Electron Microscopy is useful in identifying minerals. The SEM can provide two of the three pieces of information required to identify fibers by electron microscopy: morphology and chemistry. The third is structure as determined by Selected Area Electron Diffraction—SAED which is performed in the TEM. Although the resolution of the SEM is sufficient for very fine fibers to be seen, accuracy of chemical analysis that can be performed on the fibers varies with fiber diameter in fibers of less than 0.2 µm diameter. The TEM is a powerful tool to identify fibers too small to be resolved by light microscopy and should be used in conjunction with this method when necessary. The TEM can provide all three pieces of information required for fiber identification. Most fibers thicker than 1 µm can adequately be defined in the light microscope. The light microscope remains as the best instrument for the determination of mineral type. This is because the minerals under investigation were first described analytically with the light microscope. It is inexpensive and gives positive identification for most samples analyzed. Further, when optical techniques are inadequate, there is ample indication that alternative techniques should be used for complete identification of the sample.
1.2. Principle
Minerals consist of atoms that may be arranged in random order or in a regular arrangement. Amorphous materials have atoms in random order while crystalline materials have long range order. Many materials are transparent to light, at least for small particles or for thin sections. The properties of these materials can be investigated by the effect that the material has on light passing through it. The six asbestos minerals are all crystalline with particular properties that have been identified and cataloged. These six minerals are anisotropic. They have a regular array of atoms, but the arrangement is not the same in all directions. Each major direction of the crystal presents a different regularity. Light photons travelling in each of these main directions will encounter different electrical neighborhoods, affecting the path and time of travel. The techniques outlined in this method use the fact that light traveling through fibers or crystals in different directions will behave differently, but predictably. The behavior of the light as it travels through a crystal can be measured and compared with known or determined values to identify the mineral species. Usually, Polarized Light Microscopy (PLM) is performed with strain-free objectives on a bright-field microscope platform. This would limit the resolution of the microscope to about 0.4 µm. Because OSHA requires the counting and identification of fibers visible in phase contrast, the phase contrast platform is used to visualize the fibers with the polarizing elements added into the light path. Polarized light methods cannot identify fibers finer than about 1 µm in diameter even though they are visible. The finest fibers are usually identified by inference from the presence of larger, identifiable fiber bundles. When fibers are present, but not identifiable by light microscopy, use either SEM or TEM to determine the fiber identity.
1.3. Advantages and Disadvantages
The advantages of light microcopy are:
The minerals present can exist in asbestiform, fibrous, prismatic, or massive varieties all at the same time. Therefore, bulk methods of analysis such as X-ray diffraction, IR analysis, DTA, etc. are inappropriate where the material is not known to be fibrous.
The disadvantages are:
1.4. Method Performance
1.4.1. This method can be used for determination of asbestos content from 0 to 100% asbestos. The detection limit has not been adequately determined, although for selected samples, the limit is very low, depending on the number of particles examined. For mostly homogeneous, finely divided samples, with no difficult fibrous interferences, the detection limit is below 1%. For inhomogeneous samples (most samples), the detection limit remains undefined. NIST has conducted proficiency testing of laboratories on a national scale. Although each round is reported statistically with an average, control limits, etc., the results indicate a difficulty in establishing precision especially in the low concentration range. It is suspected that there is significant bias in the low range especially near 1%. EPA tried to remedy this by requiring a mandatory point counting scheme for samples less than 10%. The point counting procedure is tedious, and may introduce significant biases of its own. It has not been incorporated into this method.
1.4.2. The precision and accuracy of the quantitation tests performed in this method are unknown. Concentrations are easier to determine in commercial products where asbestos was deliberately added because the amount is usually more than a few percent. An analyst's results can be “calibrated” against the known amounts added by the manufacturer. For geological samples, the degree of homogeneity affects the precision.
1.4.3. The performance of the method is analyst dependent. The analyst must choose carefully and not necessarily randomly the portions for analysis to assure that detection of asbestos occurs when it is present. For this reason, the analyst must have adequate training in sample preparation, and experience in the location and identification of asbestos in samples. This is usually accomplished through substantial on-the-job training as well as formal education in mineralogy and microscopy.
1.5. Interferences
Any material which is long, thin, and small enough to be viewed under the microscope can be considered an interference for asbestos. There are literally hundreds of interferences in workplaces. The techniques described in this method are normally sufficient to eliminate the interferences. An analyst's success in eliminating the interferences depends on proper training.
Asbestos minerals belong to two mineral families: the serpentines and the amphiboles. In the serpentine family, the only common fibrous mineral is chrysotile. Occasionally, the mineral antigorite occurs in a fibril habit with morphology similar to the amphiboles. The amphibole minerals consist of a score of different minerals of which only five are regulated by federal standard: amosite, crocidolite, anthophyllite asbestos, tremolite asbestos and actinolite asbestos. These are the only amphibole minerals that have been commercially exploited for their fibrous properties; however, the rest can and do occur occasionally in asbestiform habit.
In addition to the related mineral interferences, other minerals common in building material may present a problem for some microscopists: gypsum, anhydrite, brucite, quartz fibers, talc fibers or ribbons, wollastonite, perlite, attapulgite, etc. Other fibrous materials commonly present in workplaces are: fiberglass, mineral wool, ceramic wool, refractory ceramic fibers, kevlar, nomex, synthetic fibers, graphite or carbon fibers, cellulose (paper or wood) fibers, metal fibers, etc.
Matrix embedding material can sometimes be a negative interference. The analyst may not be able to easily extract the fibers from the matrix in order to use the method. Where possible, remove the matrix before the analysis, taking careful note of the loss of weight. Some common matrix materials are: vinyl, rubber, tar, paint, plant fiber, cement, and epoxy. A further negative interference is that the asbestos fibers themselves may be either too small to be seen in Phase contrast Microscopy (PCM) or of a very low fibrous quality, having the appearance of plant fibers. The analyst's ability to deal with these materials increases with experience.
1.6. Uses and Occupational Exposure
Asbestos is ubiquitous in the environment. More than 40% of the land area of the United States is composed of minerals which may contain asbestos. Fortunately, the actual formation of great amounts of asbestos is relatively rare. Nonetheless, there are locations in which environmental exposure can be severe such as in the Serpentine Hills of California.
There are thousands of uses for asbestos in industry and the home. Asbestos abatement workers are the most current segment of the population to have occupational exposure to great amounts of asbestos. If the material is undisturbed, there is no exposure. Exposure occurs when the asbestos-containing material is abraded or otherwise disturbed during maintenance operations or some other activity. Approximately 95% of the asbestos in place in the United States is chrysotile.
Amosite and crocidolite make up nearly all the difference. Tremolite and anthophyllite make up a very small percentage. Tremolite is found in extremely small amounts in certain chrysotile deposits. Actinolite exposure is probably greatest from environmental sources, but has been identified in vermiculite containing, sprayed-on insulating materials which may have been certified as asbestos-free.
1.7. Physical and Chemical Properties
The nominal chemical compositions for the asbestos minerals were given in Section 1. Compared to cleavage fragments of the same minerals, asbestiform fibers possess a high tensile strength along the fiber axis. They are chemically inert, non- combustible, and heat resistant. Except for chrysotile, they are insoluble in Hydrochloric acid (HCl). Chrysotile is slightly soluble in HCl. Asbestos has high electrical resistance and good sound absorbing characteristics. It can be woven into cables, fabrics or other textiles, or matted into papers, felts, and mats.
1.8. Toxicology (This section is for Information Only and Should Not Be Taken as OSHA Policy)
Possible physiologic results of respiratory exposure to asbestos are mesothelioma of the pleura or peritoneum, interstitial fibrosis, asbestosis, pneumoconiosis, or respiratory cancer. The possible consequences of asbestos exposure are detailed in the NIOSH Criteria Document or in the OSHA Asbestos Standards 29 CFR 1910.1001 and 29 CFR 1926.1101 and 29 CFR 1915.1001.
2. Sampling Procedure
2.1. Equipment for Sampling
2.2. Safety Precautions
Asbestos is a known carcinogen. Take care when sampling. While in an asbestos-containing atmosphere, a properly selected and fit-tested respirator should be worn. Take samples in a manner to cause the least amount of dust. Follow these general guidelines:
2.3. Sampling Procedure
Samples of any suspect material should be taken from an inconspicuous place. Where the material is to remain, seal the sampling wound with an encapsulant to eliminate the potential for exposure from the sample site. Microscopy requires only a few milligrams of material. The amount that will fill a 20 mL scintillation vial is more than adequate. Be sure to collect samples from all layers and phases of material. If possible, make separate samples of each different phase of the material. This will aid in determining the actual hazard. DO NOT USE ENVELOPES, PLASTIC OR PAPER BAGS OF ANY KIND TO COLLECT SAMPLES. The use of plastic bags presents a contamination hazard to laboratory personnel and to other samples. When these containers are opened, a bellows effect blows fibers out of the container onto everything, including the person opening the container.
If a cork-borer type sampler is available, push the tube through the material all the way, so that all layers of material are sampled. Some samplers are intended to be disposable. These should be capped and sent to the laboratory. If a non-disposable cork borer is used, empty the contents into a scintillation vial and send to the laboratory. Vigorously and completely clean the cork borer between samples.
2.4 Shipment
Samples packed in glass vials must not touch or they might break in shipment.
3. Analysis
The analysis of asbestos samples can be divided into two major parts: sample preparation and microscopy. Because of the different asbestos uses that may be encountered by the analyst, each sample may need different preparation steps. The choices are outlined below. There are several different tests that are performed to identify the asbestos species and determine the percentage. They will be explained below.
3.1. Safety
Handle the samples in HEPA-filter equipped hoods. If samples are received in bags, envelopes or other inappropriate container, open them only in a hood having a face velocity at or greater than 100 fpm. Transfer a small amount to a scintillation vial and only handle the smaller amount.
Take care not to get this material on the skin. Wash immediately with soap and water if this happens.
3.2. Equipment
n = 1.550
n = 1.585
n = 1.590
n = 1.605
n = 1.620
n = 1.670
n = 1.680
n = 1.690
Tetrasodium
0.7 g/l
Sodium Potassium Tartrate
8.0 mg/liter
Hydrochloric Acid
99.2 g/liter
Sodium Tartrate
0.14 g/liter
3.3. Sample Pre-Preparation
Sample preparation begins with pre-preparation which may include chemical reduction of the matrix, heating the sample to dryness or heating in the muffle furnace. The end result is a sample which has been reduced to a powder that is sufficiently fine to fit under the cover slip. Analyze different phases of samples separately, e.g., tile and the tile mastic should be analyzed separately as the mastic may contain asbestos while the tile may not.
Samples with a high water content will not give the proper dispersion colors and must be dried prior to sample mounting. Remove the lid of the scintillation vial, place the bottle in the drying oven and heat at 100 °C to dryness (usually about 2 h). Samples which are not submitted to the lab in glass must be removed and placed in glass vials or aluminum weighing pans before placing them in the drying oven.
These may include samples with tar as a matrix, vinyl asbestos tile, or any other organic that can be reduced by heating. Remove the sample from the vial and weigh in a balance to determine the weight of the submitted portion. Place the sample in a muffle furnace at 500 °C for 1 to 2 h or until all obvious organic material has been removed. Retrieve, cool and weigh again to determine the weight loss on ignition. This is necessary to determine the asbestos content of the submitted sample, because the analyst will be looking at a reduced sample.
Vinyl asbestos tile is the most common material treated with this solvent, although, substances containing tar will sometimes yield to this treatment. Select a portion of the material and then grind it up if possible. Weigh the sample and place it in a test tube. Add sufficient THF to dissolve the organic matrix. This is usually about 4 to 5 mL. Remember, THF is highly flammable. Filter the remaining material through a tared silver membrane, dry and weigh to determine how much is left after the solvent extraction. Further process the sample to remove carbonate or mount directly.
Carbonate material is often found on fibers and sometimes must be removed in order to perform dispersion microscopy. Weigh out a portion of the material and place it in a test tube. Add a sufficient amount of 0.1 M HCl or decalcifying solution in the tube to react all the carbonate as evidenced by gas formation; i.e., when the gas bubbles stop, add a little more solution. If no more gas forms, the reaction is complete. Filter the material out through a tared silver membrane, dry and weigh to determine the weight lost.
3.4. Sample Preparation
Samples must be prepared so that accurate determination can be made of the asbestos type and amount present. The following steps are carried out in the low-flow hood (a low-flow hood has less than 50 fpm flow):
The preparation tools should either be disposable or cleaned thoroughly. Use vigorous scrubbing to loosen the fibers during the washing. Rinse the implements with copious amounts of water and air-dry in a dust-free environment.
Treat at least two different areas of each phase in this fashion. Choose representative areas of the sample. It may be useful to select particular areas or fibers for analysis. This is useful to identify asbestos in severely inhomogeneous samples.
When it is determined that amphiboles may be present, repeat the above process using the appropriate high-dispersion oils until an identification is made or all six asbestos minerals have been ruled out. Note that percent determination must be done in the index medium 1.550 because amphiboles tend to disappear in their matching mediums.
3.5. Analytical Procedure
The analysis consists of three parts: The determination of whether there is asbestos present, what type is present and the determination of how much is present. The general flow of the analysis is:
Examination by Becke line analysis may also be used; however, this is usually more cumbersome for asbestos determination.
For the purpose of regulation, the mineral must be one of the six minerals covered and must be in the asbestos growth habit. Large specimen samples of asbestos generally have the gross appearance of wood. Fibers are easily parted from it. Asbestos fibers are very long compared with their widths. The fibers have a very high tensile strength as demonstrated by bending without breaking. Asbestos fibers exist in bundles that are easily parted, show longitudinal fine structure and may be tufted at the ends showing “bundle of sticks” morphology. In the microscope some of these properties may not be observable. Amphiboles do not always show striations along their length even when they are asbestos. Neither will they always show tufting. They generally do not show a curved nature except for very long fibers. Asbestos and asbestiform minerals are usually characterized in groups by extremely high aspect ratios (greater than 100:1). While aspect ratio analysis is useful for characterizing populations of fibers, it cannot be used to identify individual fibers of intermediate to short aspect ratio. Observation of many fibers is often necessary to determine whether a sample consists of “cleavage fragments” or of asbestos fibers.
Most cleavage fragments of the asbestos minerals are easily distinguishable from true asbestos fibers. This is because true cleavage fragments usually have larger diameters than 1 µm. Internal structure of particles larger than this usually shows them to have no internal fibrillar structure. In addition, cleavage fragments of the monoclinic amphiboles show inclined extinction under crossed polars with no compensator. Asbestos fibers usually show extinction at zero degrees or ambiguous extinction if any at all. Morphologically, the larger cleavage fragments are obvious by their blunt or stepped ends showing prismatic habit. Also, they tend to be acicular rather than filiform.
Where the particles are less than 1 µm in diameter and have an aspect ratio greater than or equal to 3:1, it is recommended that the sample be analyzed by SEM or TEM if there is any question whether the fibers are cleavage fragments or asbestiform particles.
Care must be taken when analyzing by electron microscopy because the interferences are different from those in light microscopy and may structurally be very similar to asbestos. The classic interference is between anthophyllite and biopyribole or intermediate fiber. Use the same morphological clues for electron microscopy as are used for light microscopy, e.g. fibril splitting, internal longitudinal striation, fraying, curvature, etc.
Examine the sample, preferably in the glass vial. Determine the presence of any obvious fibrous component. Estimate a percentage based on previous experience and current observation. Determine whether any pre- preparation is necessary. Determine the number of phases present. This step may be carried out or augmented by observation at 6 to 40 × under a stereo microscope.
| Type of asbestos | Index of refraction |
|---|---|
| Chrysotile | n = 1.550. |
| Amosite | n = 1.670 or 1.680. |
| Crocidolite | n = 1.690. |
| Anthophyllite | n = 1.605 and 1.620. |
| Tremolite | n = 1.605 and 1.620. |
| Actinolite | n = 1.620. |
Where more than one liquid is suggested, the first is preferred; however, in some cases this liquid will not give good dispersion color. Take care to avoid interferences in the other liquid; e.g., wollastonite in n = 1.620 will give the same colors as tremolite. In n = 1.605 wollastonite will appear yellow in all directions. Wollastonite may be determined under crossed polars as it will change from blue to yellow as it is rotated along its fiber axis by tapping on the cover slip. Asbestos minerals will not change in this way.
Determination of the angle of extinction may, when present, aid in the determination of anthophyllite from tremolite. True asbestos fibers usually have 0° extinction or ambiguous extinction, while cleavage fragments have more definite extinction.
Continue analysis until both preparations have been examined and all present species of asbestos are identified. If there are no fibers present, or there is less than 0.1% present, end the analysis with the minimum number of slides (2).
View all of the area under the cover slip to make the percentage determination. View the fields while moving the stage, paying attention to the clumps of material. These are not usually the best areas to perform dispersion microscopy because of the interference from other materials. But, they are the areas most likely to represent the accurate percentage in the sample. Small amounts of asbestos require slower scanning and more frequent analysis of individual fields.
Report the area occluded by asbestos as the concentration. This estimate does not generally take into consideration the difference in density of the different species present in the sample. For most samples this is adequate. Simulation studies with similar materials must be carried out to apply microvisual estimation for that purpose and is beyond the scope of this procedure.
Step 1. 60% remains after heating at 550 °C for 1 h.
Step 2. 30% of the residue of step 1 remains after dissolution of carbonate in 0.1 m HCl.
Step 3. Microvisual estimation determines that 5% of the sample is chrysotile asbestos.
The reported result is:
R = (Microvisual result in percent) × (Fraction remaining after step 2) × (Fraction remaining of original sample after step 1)
R = (5) × (.30) × (.60) = 0.9%
For samples where asbestos was identified, but is less than 1.0%, report “Asbestos present, less than 1.0%.” There must have been at least two observed fibers or fiber bundles in the two preparations to be reported as present. For samples where asbestos was not seen, report as “None Detected.”
[51 FR 22733, June 20, 1986]
Editorial Note:
Federal Register
www.govinfo.gov.
4. Auxiliary Information
Because of the subjective nature of asbestos analysis, certain concepts and procedures need to be discussed in more depth. This information will help the analyst understand why some of the procedures are carried out the way they are.
4.1. Light
Light is electromagnetic energy. It travels from its source in packets called quanta. It is instructive to consider light as a plane wave. The light has a direction of travel. Perpendicular to this and mutually perpendicular to each other, are two vector components. One is the magnetic vector and the other is the electric vector. We shall only be concerned with the electric vector. In this description, the interaction of the vector and the mineral will describe all the observable phenomena. From a light source such a microscope illuminator, light travels in all different direction from the filament.
In any given direction away from the filament, the electric vector is perpendicular to the direction of travel of a light ray. While perpendicular, its orientation is random about the travel axis. If the electric vectors from all the light rays were lined up by passing the light through a filter that would only let light rays with electric vectors oriented in one direction pass, the light would then be POLARIZED.
Polarized light interacts with matter in the direction of the electric vector. This is the polarization direction. Using this property it is possible to use polarized light to probe different materials and identify them by how they interact with light.
The speed of light in a vacuum is a constant at about 2.99 × 10 8 m/s. When light travels in different materials such as air, water, minerals or oil, it does not travel at this speed. It travels slower. This slowing is a function of both the material through which the light is traveling and the wavelength or frequency of the light. In general, the more dense the material, the slower the light travels. Also, generally, the higher the frequency, the slower the light will travel. The ratio of the speed of light in a vacuum to that in a material is called the index of refraction (n). It is usually measured at 589 nm (the sodium D line). If white light (light containing all the visible wavelengths) travels through a material, rays of longer wavelengths will travel faster than those of shorter wavelengths, this separation is called dispersion. Dispersion is used as an identifier of materials as described in Section 4.6.
4.2. Material Properties
Materials are either amorphous or crystalline. The difference between these two descriptions depends on the positions of the atoms in them. The atoms in amorphous materials are randomly arranged with no long range order. An example of an amorphous material is glass. The atoms in crystalline materials, on the other hand, are in regular arrays and have long range order. Most of the atoms can be found in highly predictable locations. Examples of crystalline material are salt, gold, and the asbestos minerals.
It is beyond the scope of this method to describe the different types of crystalline materials that can be found, or the full description of the classes into which they can fall. However, some general crystallography is provided below to give a foundation to the procedures described.
With the exception of anthophyllite, all the asbestos minerals belong to the monoclinic crystal type. The unit cell is the basic repeating unit of the crystal and for monoclinic crystals can be described as having three unequal sides, two 90° angles and one angle not equal to 90°. The orthorhombic group, of which anthophyllite is a member has three unequal sides and three 90° angles. The unequal sides are a consequence of the complexity of fitting the different atoms into the unit cell. Although the atoms are in a regular array, that array is not symmetrical in all directions. There is long range order in the three major directions of the crystal. However, the order is different in each of the three directions. This has the effect that the index of refraction is different in each of the three directions. Using polarized light, we can investigate the index of refraction in each of the directions and identify the mineral or material under investigation. The indices α, β, and γ are used to identify the lowest, middle, and highest index of refraction respectively. The x direction, associated with α is called the fast axis. Conversely, the z direction is associated with γ and is the slow direction. Crocidolite has α along the fiber length making it “length-fast”. The remainder of the asbestos minerals have the γ axis along the fiber length. They are called “length-slow”. This orientation to fiber length is used to aid in the identification of asbestos.
4.3. Polarized Light Technique
Polarized light microscopy as described in this section uses the phase-polar microscope described in Section 3.2. A phase contrast microscope is fitted with two polarizing elements, one below and one above the sample. The polarizers have their polarization directions at right angles to each other. Depending on the tests performed, there may be a compensator between these two polarizing elements. Light emerging from a polarizing element has its electric vector pointing in the polarization direction of the element. The light will not be subsequently transmitted through a second element set at a right angle to the first element. Unless the light is altered as it passes from one element to the other, there is no transmission of light.
4.4. Angle of Extinction
Crystals which have different crystal regularity in two or three main directions are said to be anisotropic. They have a different index of refraction in each of the main directions. When such a crystal is inserted between the crossed polars, the field of view is no longer dark but shows the crystal in color. The color depends on the properties of the crystal. The light acts as if it travels through the crystal along the optical axes. If a crystal optical axis were lined up along one of the polarizing directions (either the polarizer or the analyzer) the light would appear to travel only in that direction, and it would blink out or go dark. The difference in degrees between the fiber direction and the angle at which it blinks out is called the angle of extinction. When this angle can be measured, it is useful in identifying the mineral. The procedure for measuring the angle of extinction is to first identify the polarization direction in the microscope. A commercial alignment slide can be used to establish the polarization directions or use anthophyllite or another suitable mineral. This mineral has a zero degree angle of extinction and will go dark to extinction as it aligns with the polarization directions. When a fiber of anthophyllite has gone to extinction, align the eyepiece reticle or graticule with the fiber so that there is a visual cue as to the direction of polarization in the field of view. Tape or otherwise secure the eyepiece in this position so it will not shift.
After the polarization direction has been identified in the field of view, move the particle of interest to the center of the field of view and align it with the polarization direction. For fibers, align the fiber along this direction. Note the angular reading of the rotating stage. Looking at the particle, rotate the stage until the fiber goes dark or “blinks out”. Again note the reading of the stage. The difference in the first reading and the second is an angle of extinction.
The angle measured may vary as the orientation of the fiber changes about its long axis. Tables of mineralogical data usually report the maximum angle of extinction. Asbestos forming minerals, when they exhibit an angle of extinction, usually do show an angle of extinction close to the reported maximum, or as appropriate depending on the substitution chemistry.
4.5. Crossed Polars with Compensator
When the optical axes of a crystal are not lined up along one of the polarizing directions (either the polarizer or the analyzer) part of the light travels along one axis and part travels along the other visible axis. This is characteristic of birefringent materials.
The color depends on the difference of the two visible indices of refraction and the thickness of the crystal. The maximum difference available is the difference between the α and the γ axes. This maximum difference is usually tabulated as the birefringence of the crystal.
For this test, align the fiber at 45° to the polarization directions in order to maximize the contribution to each of the optical axes. The colors seen are called retardation colors. They arise from the recombination of light which has traveled through the two separate directions of the crystal. One of the rays is retarded behind the other since the light in that direction travels slower. On recombination, some of the colors which make up white light are enhanced by constructive interference and some are suppressed by destructive interference. The result is a color dependent on the difference between the indices and the thickness of the crystal. The proper colors, thicknesses, and retardations are shown on a Michel-Levy chart. The three items, retardation, thickness and birefringence are related by the following relationship:
γ
α
R = retardation, t = crystal thickness in µm, and
α,γ
Examination of the equation for asbestos minerals reveals that the visible colors for almost all common asbestos minerals and fiber sizes are shades of gray and black. The eye is relatively poor at discriminating different shades of gray. It is very good at discriminating different colors. In order to compensate for the low retardation, a compensator is added to the light train between the polarization elements. The compensator used for this test is a gypsum plate of known thickness and birefringence. Such a compensator when oriented at 45° to the polarizer direction, provides a retardation of 530 nm of the 530 nm wavelength color. This enhances the red color and gives the background a characteristic red to red-magenta color. If this “full-wave” compensator is in place when the asbestos preparation is inserted into the light train, the colors seen on the fibers are quite different. Gypsum, like asbestos has a fast axis and a slow axis. When a fiber is aligned with its fast axis in the same direction as the fast axis of the gypsum plate, the ray vibrating in the slow direction is retarded by both the asbestos and the gypsum. This results in a higher retardation than would be present for either of the two minerals. The color seen is a second order blue. When the fiber is rotated 90° using the rotating stage, the slow direction of the fiber is now aligned with the fast direction of the gypsum and the fast direction of the fiber is aligned with the slow direction of the gypsum. Thus, one ray vibrates faster in the fast direction of the gypsum, and slower in the slow direction of the fiber; the other ray will vibrate slower in the slow direction of the gypsum and faster in the fast direction of the fiber. In this case, the effect is subtractive and the color seen is a first order yellow. As long as the fiber thickness does not add appreciably to the color, the same basic colors will be seen for all asbestos types except crocidolite. In crocidolite the colors will be weaker, may be in the opposite directions, and will be altered by the blue absorption color natural to crocidolite. Hundreds of other materials will give the same colors as asbestos, and therefore, this test is not definitive for asbestos. The test is useful in discriminating against fiberglass or other amorphous fibers such as some synthetic fibers. Certain synthetic fibers will show retardation colors different than asbestos; however, there are some forms of polyethylene and aramid which will show morphology and retardation colors similar to asbestos minerals. This test must be supplemented with a positive identification test when birefringent fibers are present which can not be excluded by morphology. This test is relatively ineffective for use on fibers less than 1 µm in diameter. For positive confirmation TEM or SEM should be used if no larger bundles or fibers are visible.
4.6. Dispersion Staining
Dispersion microscopy or dispersion staining is the method of choice for the identification of asbestos in bulk materials. Becke line analysis is used by some laboratories and yields the same results as does dispersion staining for asbestos and can be used in lieu of dispersion staining. Dispersion staining is performed on the same platform as the phase-polar analysis with the analyzer and compensator removed. One polarizing element remains to define the direction of the light so that the different indices of refraction of the fibers may be separately determined. Dispersion microscopy is a dark-field technique when used for asbestos. Particles are imaged with scattered light. Light which is unscattered is blocked from reaching the eye either by the back field image mask in a McCrone objective or a back field image mask in the phase condenser. The most convenient method is to use the rotating phase condenser to move an oversized phase ring into place. The ideal size for this ring is for the central disk to be just larger than the objective entry aperture as viewed in the back focal plane. The larger the disk, the less scattered light reaches the eye. This will have the effect of diminishing the intensity of dispersion color and will shift the actual color seen. The colors seen vary even on microscopes from the same manufacturer. This is due to the different bands of wavelength exclusion by different mask sizes. The mask may either reside in the condenser or in the objective back focal plane. It is imperative that the analyst determine by experimentation with asbestos standards what the appropriate colors should be for each asbestos type. The colors depend also on the temperature of the preparation and the exact chemistry of the asbestos. Therefore, some slight differences from the standards should be allowed. This is not a serious problem for commercial asbestos uses. This technique is used for identification of the indices of refraction for fibers by recognition of color. There is no direct numerical readout of the index of refraction. Correlation of color to actual index of refraction is possible by referral to published conversion tables. This is not necessary for the analysis of asbestos. Recognition of appropriate colors along with the proper morphology are deemed sufficient to identify the commercial asbestos minerals. Other techniques including SEM, TEM, and XRD may be required to provide additional information in order to identify other types of asbestos.
Make a preparation in the suspected matching high dispersion oil, e.g., n = 1.550 for chrysotile. Perform the preliminary tests to determine whether the fibers are birefringent or not. Take note of the morphological character. Wavy fibers are indicative of chrysotile while long, straight, thin, frayed fibers are indicative of amphibole asbestos. This can aid in the selection of the appropriate matching oil. The microscope is set up and the polarization direction is noted as in Section 4.4. Align a fiber with the polarization direction. Note the color. This is the color parallel to the polarizer. Then rotate the fiber rotating the stage 90° so that the polarization direction is across the fiber. This is the perpendicular position. Again note the color. Both colors must be consistent with standard asbestos minerals in the correct direction for a positive identification of asbestos. If only one of the colors is correct while the other is not, the identification is not positive. If the colors in both directions are bluish-white, the analyst has chosen a matching index oil which is higher than the correct matching oil, e.g. the analyst has used n = 1.620 where chrysotile is present. The next lower oil (Section 3.5.) should be used to prepare another specimen. If the color in both directions is yellow-white to straw-yellow-white, this indicates that the index of the oil is lower than the index of the fiber, e.g. the preparation is in n = 1.550 while anthophyllite is present. Select the next higher oil (Section 3.5.) and prepare another slide. Continue in this fashion until a positive identification of all asbestos species present has been made or all possible asbestos species have been ruled out by negative results in this test. Certain plant fibers can have similar dispersion colors as asbestos. Take care to note and evaluate the morphology of the fibers or remove the plant fibers in pre- preparation. Coating material on the fibers such as carbonate or vinyl may destroy the dispersion color. Usually, there will be some outcropping of fiber which will show the colors sufficient for identification. When this is not the case, treat the sample as described in Section 3.3. and then perform dispersion staining. Some samples will yield to Becke line analysis if they are coated or electron microscopy can be used for identification.
5. References
5.1. Crane, D.T., Asbestos in Air, OSHA method ID160, Revised November 1992.
5.2. Ford, W.E., Dana's Textbook of Mineralogy; Fourth Ed.; John Wiley and Son, New York, 1950, p. vii.
5.3. Selikoff,.I.J., Lee, D.H.K., Asbestos and Disease, Academic Press, New York, 1978, pp. 3,20.
5.4. Women Inspectors of Factories. Annual Report for 1898, H.M. Statistical Office, London, p. 170 (1898).
5.5. Selikoff, I.J., Lee, D.H.K., Asbestos and Disease, Academic Press, New York, 1978, pp. 26,30.
5.6. Campbell, W.J., et al, Selected Silicate Minerals and Their Asbestiform Varieties, United States Department of the Interior, Bureau of Mines, Information Circular 8751, 1977.
5.7. Asbestos, Code of Federal Regulations, 29 CFR 1910.1001 and 29 CFR 1926.58.
5.8. National Emission Standards for Hazardous Air Pollutants; Asbestos NESHAP Revision, Federal Register, Vol. 55, No. 224, 20 November 1990, p. 48410.
5.9. Ross, M. The Asbestos Minerals: Definitions, Description, Modes of Formation, Physical and Chemical Properties and Health Risk to the Mining Community, Nation Bureau of Standards Special Publication, Washington, DC, 1977.
5.10. Lilis, R., Fibrous Zeolites and Endemic Mesothelioma in Cappadocia, Turkey, J. Occ Medicine, 1981, 23,(8),548-550.
5.11. Occupational Exposure to Asbestos—1972, U.S. Department of Health, Education and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, HSM-72-10267.
5.12. Campbell, W.J., et al, Relationship of Mineral Habit to Size Characteristics for Tremolite Fragments and Fibers, United States Department of the Interior, Bureau of Mines, Information Circular 8367, 1979.
5.13. Mefford, D., DCM Laboratory, Denver, private communication, July 1987.
5.14. Deer, W.A., Howie, R.A., Zussman, J., Rock Forming Minerals, Longman, Thetford, UK, 1974.
5.15. Kerr, P.F., Optical Mineralogy; Third Ed. McGraw-Hill, New York, 1959.
5.16. Veblen, D.R. (Ed.), Amphiboles and Other Hydrous Pyriboles—Mineralogy, Reviews in Mineralogy, Vol 9A, Michigan, 1982, pp 1-102.
5.17. Dixon, W.C., Applications of Optical Microscopy in the Analysis of Asbestos and Quartz, ACS Symposium Series, No. 120, Analytical Techniques in Occupational Health Chemistry, 1979.
5.18. Polarized Light Microscopy, McCrone Research Institute, Chicago, 1976.
5.19. Asbestos Identification, McCrone Research Institute, G & G printers, Chicago, 1987.
5.20. McCrone, W.C., Calculation of Refractive Indices from Dispersion Staining Data, The Microscope, No 37, Chicago, 1989.
5.21. Levadie, B. (Ed.), Asbestos and Other Health Related Silicates, ASTM Technical Publication 834, ASTM, Philadelphia 1982.
5.22. Steel, E. and Wylie, A., Riordan, P.H. (Ed.), Mineralogical Characteristics of Asbestos, Geology of Asbestos Deposits, pp. 93-101, SME-AIME, 1981.
5.23. Zussman, J., The Mineralogy of Asbestos, Asbestos: Properties, Applications and Hazards, pp. 45-67 Wiley, 1979.
As used in § 1910.1000 (Table Z-1), coal tar pitch volatiles include the fused polycyclic hydrocarbons which volatilize from the distillation residues of coal, petroleum (excluding asphalt), wood, and other organic matter. Asphalt (CAS 8052-42-4, and CAS 64742-93-4) is not covered under the “coal tar pitch volatiles” standard.
[48 FR 2768, Jan. 21, 1983]
4-Nitrobiphenyl, Chemical Abstracts Service Register Number (CAS No.) 92933;
alpha-Naphthylamine, CAS No. 134327;
methyl chloromethyl ether, CAS No. 107302;
3,′-Dichlorobenzidine (and its salts) CAS No. 91941;
bis-Chloromethyl ether, CAS No. 542881;
beta-Naphthylamine, CAS No. 91598;
Benzidine, CAS No. 92875;
4-Aminodiphenyl, CAS No. 92671;
Ethyleneimine, CAS No. 151564;
beta-Propiolactone, CAS No. 57578;
2-Acetylaminofluorene, CAS No. 53963;
4-Dimethylaminoazo-benezene, CAS No. 60117; and
N-Nitrosodimethylamine, CAS No. 62759.
For the purposes of this section:
Absolute filter is one capable of retaining 99.97 percent of a mono disperse aerosol of 0.3 µm particles.
Authorized employee means an employee whose duties require him to be in the regulated area and who has been specifically assigned by the employer.
Clean change room means a room where employees put on clean clothing and/or protective equipment in an environment free of the 13 carcinogens addressed by this section. The clean change room shall be contiguous to and have an entry from a shower room, when the shower room facilities are otherwise required in this section.
Closed system means an operation involving a carcinogen addressed by this section where containment prevents the release of the material into regulated areas, non-regulated areas, or the external environment.
Decontamination means the inactivation of a carcinogen addressed by this section or its safe disposal.
Director means the Director, National Institute for Occupational Safety and Health, or any person directed by him or the Secretary of Health and Human Services to act for the Director.
Disposal means the safe removal of the carcinogens addressed by this section from the work environment.
Emergency means an unforeseen circumstance or set of circumstances resulting in the release of a carcinogen addressed by this section that may result in exposure to or contact with the material.
External environment means any environment external to regulated and nonregulated areas.
Isolated system means a fully enclosed structure other than the vessel of containment of a carcinogen addressed by this section that is impervious to the passage of the material and would prevent the entry of the carcinogen addressed by this section into regulated areas, nonregulated areas, or the external environment, should leakage or spillage from the vessel of containment occur.
Laboratory-type hood is a device enclosed on the three sides and the top and bottom, designed and maintained so as to draw air inward at an average linear face velocity of 150 feet per minute with a minimum of 125 feet per minute; designed, constructed, and maintained in such a way that an operation involving a carcinogen addressed by this section within the hood does not require the insertion of any portion of any employee's body other than his hands and arms.
Nonregulated area means any area under the control of the employer where entry and exit is neither restricted nor controlled.
Open-vessel system means an operation involving a carcinogen addressed by this section in an open vessel that is not in an isolated system, a laboratory-type hood, nor in any other system affording equivalent protection against the entry of the material into regulated areas, non-regulated areas, or the external environment.
Protective clothing means clothing designed to protect an employee against contact with or exposure to a carcinogen addressed by this section.
Regulated area means an area where entry and exit is restricted and controlled.
Employees working with a carcinogen addressed by this section within an isolated system such as a “glove box” shall wash their hands and arms upon completion of the assigned task and before engaging in other activities not associated with the isolated system.
Open-vessel system operations as defined in paragraph (b)(13) of this section are prohibited.
In cleanup of leaks of spills, maintenance, or repair operations on contaminated systems or equipment, or any operations involving work in an area where direct contact with a carcinogen addressed by this section could result, each authorized employee entering that area shall:
The employer must implement a respiratory protection program in accordance with § 1910.134 (b), (c), (d) (except (d)(1)(iii) and (iv), and (d)(3)), and (e) through (m), which covers each employee required by this section to use a respirator.
In an emergency, immediate measures including, but not limited to, the requirements of paragraphs (d)(2) (i) through (v) of this section shall be implemented.
Cancer.
Cancer; skin irritation; and acute toxicity effects.
Cancer; skin, eye and respiratory effects; acute toxicity effects; and flammability.
Cancer; skin, eye, and respiratory tract effects; acute toxicity effects; and flammability.
Cancer and acute toxicity effects.
Cancer and acute toxicity effects.
Cancer.
Cancer; mutagenicity; skin and eye effects; liver effects; kidney effects; acute toxicity effects; and flammability.
Cancer; skin irritation; eye effects; and acute toxicity effects.
Cancer.
Cancer; skin effects; and respiratory tract irritation.
Cancer; liver effects; and acute toxicity effects.
DANGER
MAY CAUSE CANCER
AUTHORIZED PERSONNEL ONLY
DANGER
MAY CAUSE CANCER
WEAR AIR-SUPPLIED HOODS, IMPERVIOUS SUITS, AND PROTECTIVE EQUIPMENT IN THIS AREA
AUTHORIZED PERSONNEL ONLY
CANCER-SUSPECT AGENT
AUTHORIZED PERSONNEL ONLY
CANCER-SUSPECT AGENT EXPOSED IN THIS AREA
IMPERVIOUS SUIT INCLUDING GLOVES, BOOTS, AND AIR-SUPPLIED HOOD REQUIRED AT ALL TIMES
AUTHORIZED PERSONNEL ONLY
No statement shall appear on or near any required sign, label, or instruction that contradicts or detracts from the effect of any required warning, information, or instruction.
At no cost to the employee, a program of medical surveillance shall be established and implemented for employees considered for assignment to enter regulated areas, and for authorized employees.
[61 FR 9242, Mar. 7, 1996, as amended at 63 FR 1286, Jan. 8, 1998; 63 FR 20099, Apr. 23, 1998; 70 FR 1141, Jan. 5, 2005; 71 FR 16672, Apr. 3, 2006; 73 FR 75584, Dec. 2, 2008; 76 FR 33608, June 8, 2011; 76 FR 80740, Dec. 27, 2011; 77 FR 17779, Mar. 26, 2012]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
See § 1910.1003, 13 carcinogens.
[61 FR 9245, Mar. 7, 1996]
Area Director means the Director for the Occupational Safety and Health Administration Area Office having jurisdiction over the geographic area in which the employer's establishment is located.
Employee exposures to vinyl chloride shall be controlled to at or below the permissible exposure limit provided in paragraph (c) of this section by engineering, work practice, and personal protective controls as follows:
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph.
The employer must implement a respiratory protection program in accordance § 1910.134 (b) through (d) (except (d)(1)(iii), and (d)(3)(iii)(B)(1) and (2)), and (f) through (m) which covers each employee required by this section to use a respirator.
A written operational plan for emergency situations shall be developed for each facility storing, handling, or otherwise using vinyl chloride as a liquid or compressed gas. Appropriate portions of the plan shall be implemented in the event of an emergency. The plan shall specifically provide that:
Each employee engaged in vinyl chloride or polyvinyl chloride operations shall be provided training in a program relating to the hazards of vinyl chloride and precautions for its safe use.
A program of medical surveillance shall be instituted for each employee exposed, without regard to the use of respirators, to vinyl chloride in excess of the action level. The program shall provide each such employee with an opportunity for examinations and tests in accordance with this paragraph. All medical examinations and procedures shall be performed by or under the supervision of a licensed physician, and shall be provided without cost to the employee.
DANGER
VINYL CHLORIDE
MAY CAUSE CANCER
AUTHORIZED PERSONNEL ONLY
DANGER
VINYL CHLORIDE
MAY CAUSE CANCER
WEAR RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING IN THIS AREA
AUTHORIZED PERSONNEL ONLY
CANCER-SUSPECT AGENT AREA
AUTHORIZED PERSONNEL ONLY
CANCER-SUSPECT AGENT IN THIS AREA
PROTECTIVE EQUIPMENT REQUIRED
AUTHORIZED PERSONNEL ONLY
CONTAMINATED WITH VINYL CHLORIDE
MAY CAUSE CANCER
CONTAMINATED WITH VINYL CHLORIDE
CANCER-SUSPECT AGENT
POLYVINYL CHLORIDE (OR TRADE NAME)
Contains
VINYL CHLORIDE
VINYL CHLORIDE IS A CANCER-SUSPECT AGENT
VINYL CHLORIDE
EXTREMELY FLAMMABLE GAS UNDER PRESSURE
CANCER-SUSPECT AGENT
CANCER-SUSPECT AGENT
Appendix A to § 1910.1017—Supplementary Medical Information
When required tests under paragraph (k)(1) of this section show abnormalities, the tests should be repeated as soon as practicable, preferably within 3 to 4 weeks. If tests remain abnormal, consideration should be given to withdrawal of the employee from contact with vinyl chloride, while a more comprehensive examination is made.
Additional tests which may be useful:
A. For kidney dysfunction: urine examination for albumin, red blood cells, and exfoliative abnormal cells.
B. Pulmonary system: Forced vital capacity, Forced expiratory volume at 1 second, and chest roentgenogram (posterior-anterior, 14 × 17 inches).
C. Additional serum tests: Lactic acid dehydrogenase, lactic acid dehydrogenase isoenzyme, protein determination, and protein electrophoresis.
D. For a more comprehensive examination on repeated abnormal serum tests: Hepatitis B antigen, and liver scanning.
[39 FR 35896, Oct. 4, 1974. Redesignated at 40 FR 23072, May 28, 1975]
Editorial Note:
Federal Register
www.govinfo.gov.
This section applies to all occupational exposures to inorganic arsenic except that this section does not apply to employee exposures in agriculture or resulting from pesticide application, the treatment of wood with preservatives or the utilization of arsenically preserved wood.
Action level means a concentration of inorganic arsenic of 5 micrograms per cubic meter of air (5 µg/m 3 ) averaged over any eight (8) hour period.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer whose duties require the person to enter a regulated area, or any person entering such an area as a designated representative of employees for the purpose of exercising the right to observe monitoring and measuring procedures under paragraph (e) of this section.
Director means the Director, National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Inorganic arsenic means copper aceto- arsenite and all inorganic compounds containing arsenic except arsine, measured as arsenic (As).
The employer shall assure that no employee is exposed to inorganic arsenic at concentrations greater than 10 micrograms per cubic meter of air (10 µg/m 3 ), averaged over any 8-hour period.
Each employer who has a workplace or work operation covered by this standard shall monitor each such workplace and work operation to accurately determine the airborne concentration of inorganic arsenic to which employees may be exposed.
Whenever there has been a production, process, control or personal change which may result in new or additional exposure to inorganic arsenic, or whenever the employer has any other reason to suspect a change which may result in new or additional exposures to inorganic arsenic, additional monitoring which complies with paragraph (e) of this section shall be conducted.
The employer shall establish regulated areas where worker exposures to inorganic arsenic, without regard to the use of respirators, are in excess of the permissible limit.
Regulated areas shall be demarcated and segregated from the rest of the workplace in any manner that minimizes the number of persons who will be exposed to inorganic arsenic.
Access to regulated areas shall be limited to authorized persons or to persons otherwise authorized by the Act or regulations issued pursuant thereto to enter such areas.
All persons entering a regulated area shall be supplied with a respirator, selected in accordance with paragraph (h)(2) of this section.
The employer shall assure that in regulated areas, food or beverages are not consumed, smoking products, chewing tobacco and gum are not used and cosmetics are not applied, except that these activities may be conducted in the lunchrooms, change rooms and showers required under paragraph (m) of this section. Drinking water may be consumed in the regulated area.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Where the possibility of skin or eye irritation from inorganic arsenic exists, and for all workers working in regulated areas, the employer shall provide at no cost to the employee and assure that employees use appropriate and clean protective work clothing and equipment such as, but not limited to:
DANGER: CONTAMINATED WITH INORGANIC ARSENIC. MAY CAUSE CANCER. DO NOT REMOVE DUST BY BLOWING OR SHAKING. DISPOSE OF INORGANIC ARSENIC CONTAMINATED WASH WATER IN ACCORDANCE WITH APPLICABLE LOCAL, STATE OR FEDERAL REGULATIONS.
CAUTION: Clothing contaminated with inorganic arsenic; do not remove dust by blowing or shaking. Dispose of inorganic arsenic contaminated wash water in accordance with applicable local, State or Federal regulations.
All surfaces shall be maintained as free as practicable of accumulations of inorganic arsenic.
Floors and other accessible surfaces contaminated with inorganic arsenic may not be cleaned by the use of compressed air, and shoveling and brushing may be used only where vacuuming or other relevant methods have been tried and found not to be effective.
Where vacuuming methods are selected, the vacuums shall be used and emptied in a manner to minimize the reentry of inorganic arsenic into the workplace.
A written housekeeping and maintenance plan shall be kept which shall list appropriate frequencies for carrying out housekeeping operations, and for cleaning and maintaining dust collection equipment. The plan shall be available for inspection by the Assistant Secretary.
Periodic cleaning of dust collection and ventilation equipment and checks of their effectiveness shall be carried out to maintain the effectiveness of the system and a notation kept of the last check of effectiveness and cleaning or maintenance.
The employer shall provide for employees working in regulated areas or subject to the possibility of skin or eye irritation from inorganic arsenic, clean change rooms equipped with storage facilities for street clothes and separate storage facilities for protective clothing and equipment in accordance with 29 CFR 1910.141(e).
The employer shall provide lavatory facilities which comply with § 1910.141(d) (1) and (2).
The employer shall provide facilities for employees working in areas where exposure, without regard to the use of respirators, exceeds 100 µg/m 3 to vacuum their protective clothing and clean or change shoes worn in such areas before entering change rooms, lunchrooms or shower rooms required by paragraph (j) of this section and shall assure that such employees use such facilities.
The employer shall assure that no employee is exposed to skin or eye contact with arsenic trichloride, or to skin or eye contact with liquid or particulate inorganic arsenic which is likely to cause skin or eye irritation.
The employer shall institute a medical surveillance program for the following employees:
The employer shall assure that all medical examinations and procedures are performed by or under the supervision of a licensed physician, and shall be provided without cost to the employee, without loss of pay and at a reasonable time and place.
By December 1, 1978, for employees initially covered by the medical provisions of this section, or thereafter at the time of initial assignment to an area where the employee is likely to be exposed over the action level at least 30 days per year, the employer shall provide each affected employee an opportunity for a medical examination, including at least the following elements:
If the employee for any reason develops signs or symptoms commonly associated with exposure to inorganic arsenic the employer shall provide an appropriate examination and emergency medical treatment.
The employer shall provide the following information to the examining physician:
DANGER
INORGANIC ARSENIC
MAY CAUSE CANCER
DO NOT EAT, DRINK OR SMOKE
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
INORGANIC ARSENIC
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
NO SMOKING OR EATING
RESPIRATOR REQUIRED
DANGER
CONTAINS INORGANIC ARSENIC
CANCER HAZARD
HARMFUL IF INHALED OR SWALLOWED
USE ONLY WITH ADEQUATE VENTILATION OR RESPIRATORY PROTECTION
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to inorganic arsenic conducted pursuant to paragraph (e) of this section.
The information contained in the appendices to this section is not intended by itself, to create any additional obligations not otherwise imposed by this standard nor detract from any existing obligation.
Appendix A to § 1910.1018—Inorganic Arsenic Substance Information Sheet
i. substance identification
A. Substance. Inorganic Arsenic.
B. Definition. Copper acetoarsenite, arsenic and all inorganic compounds containing arsenic except arsine, measured as arsenic (As).
C. Permissible Exposure Limit. 10 micrograms per cubic meter of air as determined as an average over an 8-hour period. No employee may be exposed to any skin or eye contact with arsenic trichloride or to skin or eye contact likely to cause skin or eye irritation.
D. Regulated Areas. Only employees authorized by your employer should enter a regulated area.
ii. health hazard data
A. Comments. The health hazard of inorganic arsenic is high.
B. Ways in which the chemical affects your body. Exposure to airborne concentrations of inorganic arsenic may cause lung cancer, and can be a skin irritant. Inorganic arsenic may also affect your body if swallowed. One compound in particular, arsenic trichloride, is especially dangerous because it can be absorbed readily through the skin. Because inorganic arsenic is a poison, you should wash your hands thoroughly prior to eating or smoking.
iii. protective clothing and equipment
A. Respirators. Respirators will be provided by your employer at no cost to you for routine use if your employer is in the process of implementing engineering and work practice controls or where engineering and work practice controls are not feasible or insufficient. You must wear respirators for non-routine activities or in emergency situations where you are likely to be exposed to levels of inorganic arsenic in excess of the permissible exposure limit. Since how well your respirator fits your face is very important, your employer is required to conduct fit tests to make sure the respirator seals properly when you wear it. These tests are simple and rapid and will be explained to you during training sessions.
B. Protective clothing. If you work in a regulated area, your employer is required to provide at no cost to you, and you must wear, appropriate, clean, protective clothing and equipment. The purpose of this equipment is to prevent you from bringing to your home arsenic-contaminated dust and to protect your body from repeated skin contact with inorganic arsenic likely to cause skin irritation. This clothing should include such items as coveralls or similar full-body clothing, gloves, shoes or coverlets, and aprons. Protective equipment should include face shields or vented goggles, where eye irritation may occur. y
iv. hygiene facilities and practices
You must not eat, drink, smoke, chew gum or tobacco, or apply cosmetics in the regulated area, except that drinking water is permitted. If you work in a regulated area your employer is required to provide lunchrooms and other areas for these purposes.
If you work in a regulated area, your employer is required to provide showers, washing facilities, and change rooms. You must wash your face, and hands before eating and must shower at the end of the work shift. Do not take used protective clothing out of change rooms without your employer's permission. Your employer is required to provide for laundering or cleaning of your protective clothing.
v. signs and labels
Your employer is required to post warning signs and labels for your protection. Signs must be posted in regulated areas. The signs must warn that a cancer hazard is present, that only authorized employees may enter the area, and that no smoking or eating is allowed, and that respirators must be worn.
vi. medical examinations
If your exposure to arsenic is over the Action Level (5 µg/m3)—(including all persons working in regulated areas) at least 30 days per year, or you have been exposed to arsenic for more than 10 years over the Action Level, your employer is required to provide you with a medical examination. The examination shall be every 6 months for employees over 45 years old or with more than 10 years exposure over the Action Level and annually for other covered employees. The medical examination must include a medical history; a chest X-ray (during initial examination only); skin examination and a nasal examination. The examining physician will provide a written opinion to your employer containing the results of the medical exams. You should also receive a copy of this opinion. The physician must not tell your employer any conditions he detects unrelated to occupational exposure to arsenic but must tell you those conditions.
vii. observation of monitoring
Your employer is required to monitor your exposure to arsenic and you or your representatives are entitled to observe the monitoring procedure. You are entitled to receive an explanation of the measurement procedure, and to record the results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and equipment are required to be worn, you must also be provided with and must wear the protective clothing and equipment.
viii. access to records
You or your representative are entitled to records of your exposure to inorganic arsenic and your medical examination records if you request your employer to provide them.
ix. training and notification
Additional information on all of these items plus training as to hazards of exposure to inorganic arsenic and the engineering and work practice controls associated with your job will also be provided by your employer. If you are exposed over the permissible exposure limit, your employer must inform you of that fact and the actions he is taking to reduce your exposures.
Appendix B to § 1910.1018—Substance Technical Guidelines
arsenic, arsenic trioxide, arsenic trichloride (three examples)
I. Physical and chemical properties
A. Arsenic (metal).
1. Formula: As.
2. Appearance: Gray metal.
3. Melting point: Sublimes without melting at 613C.
4. Specific Gravity: (H20 = 1):5.73.
5. Solubility in water: Insoluble.
B. Arsenic Trioxide.
1. Formula: As203, (As406).
2. Appearance: White powder.
3. Melting point: 315C.
4. Specific Gravity (H20 = 1):3.74.
5. Solubility in water: 3.7 grams in 100cc of water at 20c.
C. Arsenic Trichloride (liquid).
1. Formula: AsC13.
2. Appearance: Colorless or pale yellow liquid.
3. Melting point: −8.5C.
4. Boiling point: 130.2C.
5. Specific Gravity (H20 = 1):2.16 at 20C.
6. Vapor Pressure: 10mm Hg at 23.5C.
7. Solubility in Water: Decomposes in water.
II. Fire, explosion and reactivity data.
A. Fire: Arsenic, arsenic Trioxide and Arsenic Trichloride are nonflammable.
B. Reactivity:
1. Conditions Contributing to instability: Heat.
2. Incompatibility: Hydrogen gas can react with inorganic arsenic to form the highly toxic gas arsine.
III. Monitoring and Measurement Procedures
Samples collected should be full shift (at least 7-hour) samples. Sampling should be done using a personal sampling pump at a flow rate of 2 liters per minute. Samples should be collected on 0.8 micrometer pore size membrane filter (37mm diameter). Volatile arsenicals such as arsenic trichloride can be most easily collected in a midget bubbler filled with 15 ml. of 0.1 N NaOH.
The method of sampling and analysis should have an accuracy of not less than ±25 percent (with a confidence limit of 95 percent) for 10 micrograms per cubic meter of air (10 µg/m 3 ) and ±35 percent (with a confidence limit of 95 percent) for concentrations of inorganic arsenic between 5 and 10 µg/m 3.
Appendix C to § 1910.1018—Medical Surveillance Guidelines
I. General
Medical examinations are to be provided for all employees exposed to levels of inorganic arsenic above the action level (5 µg/m3) for at least 30 days per year (which would include among others, all employees, who work in regulated areas). Examinations are also to be provided to all employees who have had 10 years or more exposure above the action level for more than 30 days per year while working for the present or predecessor employer though they may no longer be exposed above the level.
An initial medical examination is to be provided to all such employees by December 1, 1978. In addition, an initial medical examination is to be provided to all employees who are first assigned to areas in which worker exposure will probably exceed 5 µg/m3 (after August 1, 1978) at the time of initial assignment. In addition to its immediate diagnostic usefulness, the initial examination will provide a baseline for comparing future test results. The initial examination must include as a minimum the following elements:
Periodic examinations are also to be provided to the employees listed in the first paragraph of this section. The periodic examinations shall be given annually for those covered employees 45 years of age or less with fewer than 10 years employment in areas where employee exposure exceeds the action level (5 µg/m 3 ). Periodic examinations need not include sputum cytology or chest X-ray and only an updated medical history is required.
Periodic examinations for other covered employees shall be provided every six (6) months. These examinations shall include all tests required in the initial examination, except the chest X-ray, and the medical history need only be updated.
The examination contents are minimum requirements. Additional tests such as lateral and oblique X-rays or pulmonary function tests may be useful. For workers exposed to three arsenicals which are associated with lymphatic cancer, copper acetoarsenite, potassium arsenite, or sodium arsenite the examination should also include palpation of superficial lymph nodes and complete blood count.
ii. noncarcinogenic effects
The OSHA standard is based on minimizing risk of exposed workers dying of lung cancer from exposure to inorganic arsenic. It will also minimize skin cancer from such exposures.
The following three sections quoted from “Occupational Diseases: A Guide to Their Recognition”, Revised Edition, June 1977, National Institute for Occupational Safety and Health is included to provide information on the nonneoplastic effects of exposure to inorganic arsenic. Such effects should not occur if the OSHA standards are followed.
A. Local —Trivalent arsenic compounds are corrosive to the skin. Brief contact has no effect but prolonged contact results in a local hyperemia and later vesicular or pustular eruption. The moist mucous membranes are most sensitive to the irritant action. Conjunctiva, moist and macerated areas of skin, the eyelids, the angles of the ears, nose, mouth, and respiratory mucosa are also vulnerable to the irritant effects. The wrists are common sites of dermatitis, as are the genitalia if personal hygiene is poor. Perforations of the nasal septum may occur. Arsenic trioxide and pentoxide are capable of producing skin sensitization and contact dermatitis. Arsenic is also capable of producing keratoses, especially of the palms and soles.
B. Systemic —The acute toxic effects of arsenic are generally seen following ingestion of inorganic arsenical compounds. This rarely occurs in an industrial setting. Symptoms develop within 1/2 to 4 hours following ingestion and are usually characterized by constriction of the throat followed by dysphagia, epigastric pain, vomiting, and watery diarrhea. Blood may appear in vomitus and stools. If the amount ingested is sufficiently high, shock may develop due to severe fluid loss, and death may ensue in 24 hours. If the acute effects are survived, exfoliative dermatitis and peripheral neuritis may develop.
Cases of acute arsenical poisoning due to inhalation are exceedingly rare in industry. When it does occur, respiratory tract symptoms—cough, chest pain, dyspnea—giddiness, headache, and extreme general weakness precede gastrointestinal symptoms. The acute toxic symptoms of trivalent arsenical poisoning are due to severe inflammation of the mucous membranes and greatly increased permeability of the blood capillaries.
Chronic arsenical poisoning due to ingestion is rare and generally confined to patients taking prescribed medications. However, it can be a concomitant of inhaled inorganic arsenic from swallowed sputum and improper eating habits. Symptoms are weight loss, nausea and diarrhea alternating with constipation, pigmentation and eruption of the skin, loss of hair, and peripheral neuritis. Chronic hepatitis and cirrhosis have been described. Polyneuritis may be the salient feature, but more frequently there are numbness and parasthenias of “glove and stocking” distribution. The skin lesions are usually melanotic and keratotic and may occasionally take the form of an intradermal cancer of the squamous cell type, but without infiltrative properties. Horizontal white lines (striations) on the fingernails and toenails are commonly seen in chronic arsenical poisoning and are considered to be a diagnostic accompaniment of arsenical polyneuritis.
Inhalation of inorganic arsenic compounds is the most common cause of chronic poisoning in the industrial situation. This condition is divided into three phases based on signs and symptoms.
First Phase: The worker complains of weakness, loss of appetite, some nausea, occasional vomiting, a sense of heaviness in the stomach, and some diarrhea.
Second Phase: The worker complains of conjunctivitis, a catarrhal state of the mucous membranes of the nose, larynx, and respiratory passage. Coryza, hoarseness, and mild tracheobronchitis may occur. Perforation of the nasal septum is common, and is probably the most typical lesion of the upper respiratory tract in occupational exposure to arsenical dust. Skin lesions, eczematoid and allergic in type, are common.
Third Phase: The worker complains of symptoms of peripheral neuritis, initially of hands and feet, which is essentially sensory. In more severe cases, motor paralyses occur; the first muscles affected are usually the toe extensors and the peronei. In only the most severe cases will paralysis of flexor muscles of the feet or of the extensor muscles of hands occur.
Liver damage from chronic arsenical poisoning is still debated, and as yet the question is unanswered. In cases of chronic and acute arsenical poisoning, toxic effects to the myocardium have been reported based on EKG changes. These findings, however, are now largely discounted and the EKG changes are ascribed to electrolyte disturbances concomitant with arsenicalism. Inhalation of arsenic trioxide and other inorganic arsenical dusts does not give rise to radiological evidence or pneumoconiosis. Arsenic does have a depressant effect upon the bone marrow, with disturbances of both erythropoiesis and myelopoiesis.
Bibliography
Dinman, B. D. 1960. Arsenic; chronic human intoxication. J. Occup. Med. 2:137.
Elkins, H. B. 1959. The Chemistry of Industrial Toxicology, 2nd ed. John Wiley and Sons, New York.
Holmquist, L. 1951. Occupational arsenical dermatitis; a study among employees at a copper-ore smelting works including investigations of skin reactions to contact with arsenic compounds. Acta. Derm. Venereol. (Supp. 26) 31:1.
Pinto, S. S., and C. M. McGill. 1953. Arsenic trioxide exposure in industry. Ind. Med. Surg. 22:281.
Pinto, S. S., and K. W. Nelson. 1976. Arsenic toxicology and industrial exposure. Annu. Rev. Pharmacol. Toxicol. 16:95.
Vallee, B. L., D. D. Ulmer, and W. E. C. Wacker. 1960. Arsenic toxicology and biochemistry. AMA Arch. Indust. Health 21:132.
[39 FR 23502, June 27, 1974, as amended at 43 FR 19624, May 5, 1978; 43 FR 28472, June 30, 1978; 45 FR 35282, May 23, 1980; 54 FR 24334, June 7, 1989; 58 FR 35310, June 30, 1993; 61 FR 5508, Feb. 13, 1996; 61 FR 9245, Mar. 7, 1996; 63 FR 1286, Jan. 8, 1998; 63 FR 33468, June 18, 1998; 70 FR 1141, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June 8, 2011; 77 FR 17780, Mar. 26, 2012; 84 FR 21470, May 14, 2019]
The purpose of this section is to provide employees and their designated representatives a right of access to relevant exposure and medical records; and to provide representatives of the Assistant Secretary a right of access to these records in order to fulfill responsibilities under the Occupational Safety and Health Act. Access by employees, their representatives, and the Assistant Secretary is necessary to yield both direct and indirect improvements in the detection, treatment, and prevention of occupational disease. Each employer is responsible for assuring compliance with this section, but the activities involved in complying with the access to medical records provisions can be carried out, on behalf of the employer, by the physician or other health care personnel in charge of employee medical records. Except as expressly provided, nothing in this section is intended to affect existing legal and ethical obligations concerning the maintenance and confidentiality of employee medical information, the duty to disclose information to a patient/employee or any other aspect of the medical-care relationship, or affect existing legal obligations concerning the protection of trade secret information.
The medical record for each employee shall be preserved and maintained for at least the duration of employment plus thirty (30) years, except that the following types of records need not be retained for any specified period:
Each employee exposure record shall be preserved and maintained for at least thirty (30) years, except that:
1 Material safety data sheets must be kept for those chemicals currently in use that are effected by the Hazard Communication Standard in accordance with 29 CFR 1910.1200(g).
Each analysis using exposure or medial records shall be preserved and maintained for at least thirty (30) years.
The information contained in appendices A and B to this section is not intended, by itself, to create any additional obligations not otherwise imposed by this section nor detract from any existing obligation.
Appendix A to § 1910.1020—Sample Authorization Letter for the Release of Employee Medical Record Information to a Designated Representative (Non-Mandatory)
I, _____ (full name of worker/patient), hereby authorize ______ (individual or organization holding the medical records) to release to ______ (individual or organization authorized to receive the medical information), the following medical information from my personal medical records:
I give my permission for this medical information to be used for the following purpose:
but I do not give permission for any other use or re-disclosure of this information.
Full name of Employee or Legal Representative
Signature of Employee or Legal Representative
Date of Signature
Appendix B to § 1910.1020—Availability of NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) (Non-Mandatory)
The final regulation, 29 CFR 1910.20, applies to all employee exposure and medical records, and analyses thereof, of employees exposed to toxic substances or harmful physical agents (paragraph (b)(2)). The term toxic substance or harmful physical agent is defined by paragraph (c)(13) to encompass chemical substances, biological agents, and physical stresses for which there is evidence of harmful health effects. The regulation uses the latest printed edition of the National Institute for Occupational Safety and Health (NIOSH) Registry of Toxic Effects of Chemical Substances (RTECS) as one of the chief sources of information as to whether evidence of harmful health effects exists. If a substance is listed in the latest printed RTECS, the regulation applies to exposure and medical records (and analyses of these records) relevant to employees exposed to the substance.
It is appropriate to note that the final regulation does not require that employers purchase a copy of RTECS, and many employers need not consult RTECS to ascertain whether their employee exposure or medical records are subject to the rule. Employers who do not currently have the latest printed edition of the NIOSH RTECS, however, may desire to obtain a copy. The RTECS is issued in an annual printed edition as mandated by section 20(a)(6) of the Occupational Safety and Health Act (29 U.S.C. 669(a)(6)).
The Introduction to the 1980 printed edition describes the RTECS as follows:
“The 1980 edition of the Registry of Toxic Effects of Chemical Substances, formerly known as the Toxic Substances list, is the ninth revision prepared in compliance with the requirements of Section 20(a)(6) of the Occupational Safety and Health Act of 1970 (Public Law 91-596). The original list was completed on June 28, 1971, and has been updated annually in book format. Beginning in October 1977, quarterly revisions have been provided in microfiche. This edition of the Registry contains 168,096 listings of chemical substances: 45,156 are names of different chemicals with their associated toxicity data and 122,940 are synonyms. This edition includes approximately 5,900 new chemical compounds that did not appear in the 1979 Registry. (p. xi)
“The Registry's purposes are many, and it serves a variety of users. It is a single source document for basic toxicity information and for other data, such as chemical identifiers ad information necessary for the preparation of safety directives and hazard evaluations for chemical substances. The various types of toxic effects linked to literature citations provide researchers and occupational health scientists with an introduction to the toxicological literature, making their own review of the toxic hazards of a given substance easier. By presenting data on the lowest reported doses that produce effects by several routes of entry in various species, the Registry furnishes valuable information to those responsible for preparing safety data sheets for chemical substances in the workplace. Chemical and production engineers can use the Registry to identify the hazards which may be associated with chemical intermediates in the development of final products, and thus can more readily select substitutes or alternative processes which may be less hazardous. Some organizations, including health agencies and chemical companies, have included the NIOSH Registry accession numbers with the listing of chemicals in their files to reference toxicity information associated with those chemicals. By including foreign language chemical names, a start has been made toward providing rapid identification of substances produced in other countries. (p. xi)
“In this edition of the Registry, the editors intend to identify “all known toxic substances” which may exist in the environment and to provide pertinent data on the toxic effects from known doses entering an organism by any route described. (p xi)
“It must be reemphasized that the entry of a substance in the Registry does not automatically mean that it must be avoided. A listing does mean, however, that the substance has the documented potential of being harmful if misused, and care must be exercised to prevent tragic consequences. Thus, the Registry lists many substances that are common in everyday life and are in nearly every household in the United States. One can name a variety of such dangerous substances: prescription and non-prescription drugs; food additives; pesticide concentrates, sprays, and dusts; fungicides; herbicides; paints; glazes, dyes; bleaches and other household cleaning agents; alkalies; and various solvents and diluents. The list is extensive because chemicals have become an integral part of our existence.”
The RTECS printed edition may be purchased from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402 (202-783-3238).
Some employers may desire to subscribe to the quarterly update to the RTECS which is published in a microfiche edition. An annual subscription to the quarterly microfiche may be purchased from the GPO (Order the “Microfiche Edition, Registry of Toxic Effects of Chemical Substances”). Both the printed edition and the microfiche edition of RTECS are available for review at many university and public libraries throughout the country. The latest RTECS editions may also be examined at the OSHA Technical Data Center, Room N2439—Rear, United States Department of Labor, 200 Constitution Avenue, NW., Washington, DC 20210 (202-523-9700), or at any OSHA Regional or Area Office ( See, major city telephone directories under United States Government-Labor Department).
[53 FR 38163, Sept. 29, 1988; 53 FR 49981, Dec. 13, 1988, as amended at 54 FR 24333, June 7, 1989; 55 FR 26431, June 28, 1990; 61 FR 9235, Mar. 7, 1996. Redesignated at 61 FR 31430, June 20, 1996, as amended at 71 FR 16673, Apr. 3, 2006; 76 FR 33608, June 8, 2011]
As used in this standard:
Action level means a concentration of airborne beryllium of 0.1 micrograms per cubic meter of air (µg/m 3 ) calculated as an 8-hour time-weighted average (TWA).
Airborne exposure and airborne exposure to beryllium mean the exposure to airborne beryllium that would occur if the employee were not using a respirator.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, United States Department of Labor, or designee.
Beryllium lymphocyte proliferation test (BeLPT) means the measurement of blood lymphocyte proliferation in a laboratory test when lymphocytes are challenged with a soluble beryllium salt.
Beryllium sensitization means a response in the immune system of a specific individual who has been exposed to beryllium. There are no associated physical or clinical symptoms and no illness or disability with beryllium sensitization alone, but the response that occurs through beryllium sensitization can enable the immune system to recognize and react to beryllium. While not every beryllium-sensitized person will develop chronic beryllium disease (CBD), beryllium sensitization is essential for development of CBD.
Beryllium work area means any work area where materials that contain at least 0.1 percent beryllium by weight are processed either:
CBD diagnostic center means a medical diagnostic center that has a pulmonologist or pulmonary specialist on staff and on-site facilities to perform a clinical evaluation for the presence of chronic beryllium disease (CBD). The CBD diagnostic center must have the capacity to perform pulmonary function testing (as outlined by the American Thoracic Society criteria), bronchoalveolar lavage (BAL), and transbronchial biopsy. The CBD diagnostic center must also have the capacity to transfer BAL samples to a laboratory for appropriate diagnostic testing within 24 hours. The pulmonologist or pulmonary specialist must be able to interpret the biopsy pathology and the BAL diagnostic test results.
Chronic beryllium disease (CBD) means a chronic granulomatous lung disease caused by inhalation of airborne beryllium by an individual who is beryllium sensitized.
Confirmed positive means the person tested has had two abnormal BeLPT test results, an abnormal and a borderline test result, or three borderline test results, obtained from tests conducted within a three-year period. It also means the result of a more reliable and accurate test indicating a person has been identified as having beryllium sensitization.
Contaminated with beryllium and beryllium-contaminated mean contaminated with dust, fumes, mists, or solutions containing beryllium in concentrations greater than or equal to 0.1 percent by weight.
Dermal contact with beryllium means skin exposure to:
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment, which may or does result in an uncontrolled and unintended release of airborne beryllium that presents a significant hazard.
High-efficiency particulate air (HEPA) filter means a filter that is at least 99.97 percent efficient in removing particles 0.3 micrometers in diameter.
Objective data means information, such as air monitoring data from industry-wide surveys or calculations based on the composition of a substance, demonstrating airborne exposure to beryllium associated with a particular product or material or a specific process, task, or activity. The data must reflect workplace conditions closely resembling or with a higher airborne exposure potential than the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Physician or other licensed health care professional (PLHCP) means an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows the individual to independently provide or be delegated the responsibility to provide some or all of the health care services required by paragraph (k) of this standard.
Regulated area means an area, including temporary work areas where maintenance or non-routine tasks are performed, where an employee's airborne exposure exceeds, or can reasonably be expected to exceed, either the time-weighted average (TWA) permissible exposure limit (PEL) or short term exposure limit (STEL).
This standard means this beryllium standard, 29 CFR 1910.1024.
The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 0.2 µg/m 3 calculated as an 8-hour TWA.
The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 2.0 µg/m 3 as determined over a sampling period of 15 minutes.
The employer must assess the airborne exposure of each employee who is or may reasonably be expected to be exposed to airborne beryllium in accordance with either the performance option in paragraph (d)(2) or the scheduled monitoring option in paragraph (d)(3) of this standard.
The employer must assess the 8-hour TWA exposure and the 15-minute short-term exposure for each employee on the basis of any combination of air monitoring data and objective data sufficient to accurately characterize airborne exposure to beryllium.
The employer must reassess airborne exposure whenever a change in the production, process, control equipment, personnel, or work practices may reasonably be expected to result in new or additional airborne exposure at or above the action level or STEL, or when the employer has any reason to believe that new or additional airborne exposure at or above the action level or STEL has occurred.
The employer must ensure that all air monitoring samples used to satisfy the monitoring requirements of paragraph (d) of this standard are evaluated by a laboratory that can measure beryllium to an accuracy of plus or minus 25 percent within a statistical confidence level of 95 percent for airborne concentrations at or above the action level.
The employer must limit access to regulated areas to:
The employer must not rotate employees to different jobs to achieve compliance with the PELs.
The employer must provide respiratory protection at no cost to the employee and ensure that each employee uses respiratory protection:
Where this standard requires an employer to provide respiratory protection, the selection and use of such respiratory protection must be in accordance with the Respiratory Protection standard (§ 1910.134).
The employer must provide at no cost, and ensure that each employee uses, appropriate personal protective clothing and equipment in accordance with the written exposure control plan required under paragraph (f)(1) of this standard and OSHA's Personal Protective Equipment standards (subpart I of this part):
For each employee working in a beryllium work area or who can reasonably be expected to have dermal contact with beryllium, the employer must:
In addition to the requirements of paragraph (i)(1)(i) of this standard, the employer must provide employees who are required to use personal protective clothing or equipment under paragraph (h)(1)(ii) of this standard with a designated change room in accordance with this standard and the Sanitation standard (§ 1910.141) where employees are required to remove their personal clothing.
Wherever the employer allows employees to consume food or beverages at a worksite where beryllium is present, the employer must ensure that:
The employer must ensure that no employees eat, drink, smoke, chew tobacco or gum, or apply cosmetics in regulated areas.
The employer must provide a medical examination:
The employer must ensure that the examining PLHCP (and the agreed-upon CBD diagnostic center, if an evaluation is required under paragraph (k)(7) of this standard) has a copy of this standard and must provide the following information, if known:
The employer must ensure that the employee receives a written medical report from the licensed physician within 45 days of the examination (including any follow-up BeLPT required under paragraph (k)(3)(ii)(E) of this standard) and that the PLHCP explains the results of the examination to the employee. The written medical report must contain:
The employer must provide and display warning signs at each approach to a regulated area so that each employee is able to read and understand the signs and take necessary protective steps before entering the area.
DANGER
REGULATED AREA
BERYLLIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
AUTHORIZED PERSONNEL ONLY
WEAR RESPIRATORY PROTECTION AND PERSONAL PROTECTIVE CLOTHING AND EQUIPMENT IN THIS AREA
Consistent with the HCS (§ 1910.1200), the employer must label each immediate container of clothing, equipment, and materials contaminated with beryllium, and must, at a minimum, include the following on the label:
DANGER
CONTAINS BERYLLIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
AVOID CREATING DUST
DO NOT GET ON SKIN
The employer must make a copy of this standard and its appendices readily available at no cost to each employee and designated employee representative(s).
Upon request, the employer must make all records maintained as a requirement of this standard available for examination and copying to the Assistant Secretary, the Director, each employee, and each employee's designated representative(s) in accordance the Records Access standard (§ 1910.1020).
The employer must comply with the requirements involving transfer of records set forth in the Records Access standard (§ 1910.1020).
This standard shall become effective March 10, 2017.
December 12, 2018.
Appendix A to § 1910.1024—Operations for Establishing Beryllium Work Areas
Paragraph (b) of this standard defines a beryllium work area as any work area where materials that contain at least 0.1 percent beryllium by weight are processed (1) during any of the operations listed in Appendix A of this standard, or (2) where employees are, or can reasonably be expected to be, exposed to airborne beryllium at or above the action level. Table A.1 in this appendix sets forth the operations that, where performed under the circumstances described in the column heading above the particular operations, trigger the requirement for a beryllium work area.
| Beryllium metal alloy operations (generally <10% beryllium by weight) | Beryllium composite operations (generally >10% beryllium by weight) and beryllium metal operations | Beryllium oxide operations |
|---|---|---|
| Abrasive Blasting. | Abrasive Blasting. | Abrasive Blasting. |
| Abrasive Processing. | Abrasive Processing. | Abrasive Processing. |
| Abrasive Sawing. | Abrasive Sawing. | Abrasive Sawing. |
| Annealing. | Annealing. | Boring. |
| Bright Cleaning. | Atomizing. | Brazing (>1,100 °C). |
| Brushing. | Attritioning. | Broaching with green ceramic. |
| Buffing. | Blanking. | Brushing. |
| Burnishing. | Bonding. | Buffing. |
| Casting. | Boring. | Centerless grinding. |
| Centerless Grinding. | Breaking. | Chemical Cleaning. |
| Chemical Cleaning. | Bright Cleaning. | Chemical Etching. |
| Chemical Etching. | Broaching. | CNC Machining. |
| Chemical Milling. | Brushing. | Cold Isostatic Pressing (CIP). |
| Dross Handling. | Buffing. | Crushing. |
| Deburring (grinding). | Burnishing. | Cutting. |
| Electrical Chemical Machining (ECM). | Casting. | Deburring (grinding). |
| Electrical Discharge Machining (EDM). | Centerless Grinding. | Deburring (non-grinding). |
| Extrusion. | Chemical Cleaning. | Destructive Testing. |
| Forging. | Chemical Etching | Dicing. |
| Grinding. | Chemical Milling. | Drilling. |
| Heat Treating (in air). | CNC Machining | Dry/wet Tumbling. |
| High Speed Machining (>10,000 rpm). | Cold Isostatic Pressing. | Extrusion. |
| Hot Rolling. | Cold Pilger. | Filing by Hand. |
| Lapping. | Crushing. | Firing of Green Ceramic. |
| Laser Cutting. | Cutting. | Firing of Refractory Metallization (>1,100 °C). |
| Laser Machining. | Deburring. | Grinding. |
| Laser Scribing. | Dicing. | Honing. |
| Laser Marking. | Drawing. | Hot Isostatic Pressing (HIP). |
| Melting. | Drilling. | Lapping. |
| Photo-Etching. | Dross Handling. | Laser Cutting. |
| Pickling. | Electrical Chemical Machining (ECM). | Laser Machining. |
| Point and Chamfer. | Electrical Discharge Machining (EDM). | Laser Scribing. |
| Polishing. | Extrusion. | Laser Marking. |
| Torch Cutting ( i.e. , oxy-acetylene). | Filing by Hand. | Machining. |
| Tumbling. | Forging. | Milling. |
| Water-jet Cutting. | Grinding. | Piercing. |
| Welding. | Heading. | Mixing. |
| Sanding. | Heat Treating. | Plasma Spray. |
| Slab Milling. | Honing. | Polishing. |
| Hot Isostatic Pressing (HIP). | Powder Handling. | |
| Lapping. | Powder Pressing. | |
| Laser Cutting. | Reaming. | |
| Laser Machining. | Sanding. | |
| Laser Scribing. | Sectioning. | |
| Laser Marking. | Shearing. | |
| Machining. | Sintering of Green Ceramic. | |
| Melting. | Sintering of Refractory Metallization (>1,100 °C). | |
| Milling. | Snapping. | |
| Mixing. | Spray Drying. | |
| Photo-Etching. | Tape Casting. | |
| Pickling. | Turning. | |
| Piercing. | Water Jet Cutting. | |
| Pilger. | ||
| Plasma Spray. | ||
| Point and Chamfer. | ||
| Polishing. | ||
| Powder Handling. | ||
| Powder Pressing. | ||
| Pressing. | ||
| Reaming. | ||
| Roll Bonding. | ||
| Rolling. | ||
| Sanding. | ||
| Sawing (tooth blade). | ||
| Shearing. | ||
| Sizing. | ||
| Skiving. | ||
| Slitting. | ||
| Snapping. | ||
| Sputtering. | ||
| Stamping. | ||
| Spray Drying. | ||
| Tapping. | ||
| Tensile Testing. | ||
| Torch Cutting ( i.e. , oxy acetylene). | ||
| Trepanning. | ||
| Tumbling | ||
| Turning. | ||
| Vapor Deposition. | ||
| Water-Jet Cutting. | ||
| Welding. |
[82 FR 2736, Jan. 9, 2017, as amended at 83 FR 19948, May 7, 2018; 83 FR 39360, Aug. 9, 2018; 85 FR 42625, July 14, 2020]
Action level means employee exposure, without regard to the use of respirators, to an airborne concentration of lead of 30 micrograms per cubic meter of air (30 µg/m 3 ) averaged over an 8-hour period.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Director means the Director, National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health, Education, and Welfare, or designee.
Lead means metallic lead, all inorganic lead compounds, and organic lead soaps. Excluded from this definition are all other organic lead compounds.
Maximum permissible limit (in µg/m 3 ) = 400 ÷ hours worked in the day.
Each employer who has a workplace or work operation covered by this standard shall determine if any exployee may be exposed to lead at or above the action level.
Where a determination, conducted under paragraphs (d) (2) and (3) of this section is made that no employee is exposed to airborne concentrations of lead at or above the action level, the employer shall make a written record of such determination. The record shall include at least the information specified in paragraph (d)(3) of this section and shall also include the date of determination, location within the worksite, and the name number of each employee monitored.
Whenever there has been a production, process, control or personnel change which may result in new or additional exposure to lead, or whenever the employer has any other reason to suspect a change which may result in new or additional exposures to lead, additional monitoring in accordance with this paragraph shall be conducted.
The employer shall use a method of monitoring and analysis which has an accuracy (to a confidence level of 95%) of not less than plus or minus 20 percent for airborne concentrations of lead equal to or greater than 30 µg/m 3.
| Industry | Compliance dates: 1 (50 µg/m 3 ) |
|---|---|
| Lead chemicals, secondary copper smelting | July 19, 1996. |
| Nonferrous foundries | July 19, 1996. 2 |
| Brass and bronze ingot manufacture | 6 years. 3 |
| 1 Calculated by counting from the date the stay on implementation of paragraph (e)(1) was lifted by the U.S. Court of Appeals for the District of Columbia, the number of years specified in the 1978 lead standard and subsequent amendments for compliance with the PEL of 50 µg/m 3 for exposure to airborne concentrations of lead levels for the particular industry. | |
| 2 Large nonferrous foundries (20 or more employees) are required to achieve the PEL of 50 µg/m 3 by means of engineering and work practice controls. Small nonferrous foundries (fewer than 20 employees) are required to achieve an 8-hour TWA of 75 µg/m 3 by such controls. | |
| 3 Expressed as the number of years from the date on which the Court lifts the stay on the implementation of paragraph (e)(1) for this industry for employers to achieve a lead in air concentration of 75 µg/m 3 . Compliance with paragraph (e) in this industry is determined by a compliance directive that incorporates elements from the settlement agreement between OSHA and representatives of the industry. |
Where engineering and work practice controls do not reduce employee exposure to or below the 50 µg/m 3 permissible exposure limit, the employer shall supplement these controls with respirators in accordance with paragraph (f).
If air from exhaust ventilation is recirculated into the workplace, the employer shall assure that (A) the system has a high efficiency filter with reliable back-up filter; and (B) controls to monitor the concentration of lead in the return air and to bypass the recirculation system automatically if it fails are installed, operating, and maintained.
If administrative controls are used as a means of reducing employees TWA exposure to lead, the employer shall establish and implement a job rotation schedule which includes:
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
If an employee is exposed to lead above the PEL, without regard to the use of respirators or where the possibility of skin or eye irritation exists, the employer shall provide at no cost to the employee and assure that the employee uses appropriate protective work clothing and equipment such as, but not limited to:
DANGER: CLOTHING AND EQUIPMENT CONTAMINATED WITH LEAD. MAY DAMAGE FERTILITY OR THE UNBORN CHILD. CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM. DO NOT EAT, DRINK OR SMOKE WHEN HANDLING. DO NOT REMOVE DUST BY BLOWING OR SHAKING. DISPOSE OF LEAD CONTAMINATED WASH WATER IN ACCORDANCE WITH APPLICABLE LOCAL, STATE, OR FEDERAL REGULATIONS.
CAUTION: CLOTHING CONTAMINATED WITH LEAD. DO NOT REMOVE DUST BY BLOWING OR SHAKING. DISPOSE OF LEAD CONTAMINATED WASH WATER IN ACCORDANCE WITH APPLICABLE LOCAL, STATE, OR FEDERAL REGULATIONS.
All surfaces shall be maintained as free as practicable of accumulations of lead.
Where vacuuming methods are selected, the vacuums shall be used and emptied in a manner which minimizes the reentry of lead into the workplace.
The employer shall provide an adequate number of lavatory facilities which comply with § 1910.141(d) (1) and (2) of this part.
The employer shall make available biological monitoring in the form of blood sampling and analysis for lead and zinc protoporphyrin levels to each employee covered under paragraph (j)(1)(i) of this section on the following schedule:
Whenever the results of a blood lead level test indicate that an employee's blood lead level is at or above the numerical criterion for medical removal under paragraph (k)(1)(i)(A) of this section, the employer shall provide a second (follow-up) blood sampling test within two weeks after the employer receives the results of the first blood sampling test.
Blood lead level sampling and analysis provided pursuant to this section shall have an accuracy (to a confidence level of 95 percent) within plus or minus 15 percent or 6 µg/100ml, whichever is greater, and shall be conducted by a laboratory licensed by the Center for Disease Control, United States Department of Health, Education and Welfare (CDC) or which has received a satisfactory grade in blood lead proficiency testing from CDC in the prior twelve months.
Within five working days after the receipt of biological monitoring results, the employer shall notify in writing each employee whose blood lead level is at or above 40 µg/100 g:
The employer shall make available medical examinations and consultations to each employee covered under paragraph (j)(1)(i) of this section on the following schedule:
Medical examinations made available pursuant to paragraph (j)(3)(i) (A) through (B) of this section shall include the following elements:
The content of medical examinations made available pursuant to paragraph (j)(3)(i) (C) through (D) of this section shall be determined by an examining physician and, if requested by an employee, shall include pregnancy testing or laboratory evaluation of male fertility.
The employer and an employee or authorized employee representative may agree upon the use of any expeditious alternate physician determination mechanism in lieu of the multiple physician review mechanism provided by this paragraph so long as the alternate mechanism otherwise satisfies the requirements contained in this paragraph.
Where the multiple physician review mechanism, or alternate medical determination mechanism used pursuant to the medical surveillance provisions of this section, has not yet resulted in a final medical determination with respect to an employee, the employer shall act as follows:
The employer may remove the employee from exposure to lead, provide special protective measures to the employee, or place limitations upon the employee, consistent with the medical findings, determinations, or recommendations of any of the physicians who have reviewed the employee's health status.
The employer may return the employee to his or her former job status, end any special protective measures provided to the employee, and remove any limitations placed upon the employee, consistent with the medical findings, determinations, or recommendations of any of the physicians who have reviewed the employee's health status, with two exceptions. If
The employer shall provide to an employee up to eighteen (18) months of medical removal protection benefits on each occasion that an employee is removed from exposure to lead or otherwise limited pursuant to this section.
For the purposes of this section, the requirement that an employer provide medical removal protection benefits means that the employer shall maintain the earnings, seniority and other employment rights and benefits of an employee as though the employee had not been removed from normal exposure to lead or otherwise limited.
If a removed employee files a claim for workers' compensation payments for a lead-related disability, then the employer shall continue to provide medical removal protection benefits pending disposition of the claim. To the extent that an award is made to the employee for earnings lost during the period of removal, the employer's medical removal protection obligation shall be reduced by such amount. The employer shall receive no credit for workers' compensation payments received by the employee for treatment related expenses.
The employer's obligation to provide medical removal protection benefits to a removed employee shall be reduced to the extent that the employee receives compensation for earnings lost during the period of removal either from a publicly or employer-funded compensation program, or receives income from employment with another employer made possible by virtue of the employee's removal.
Where an employer, although not required by this section to do so, removes an employee from exposure to lead or otherwise places limitations on an employee due to the effects of lead exposure on the employee's medical condition, the employer shall provide medical removal protection benefits to the employee equal to that required by paragraph (k)(2)(i) of this section.
DANGER
LEAD
MAY DAMAGE FERTILITY OR THE UNBORN CHILD
CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM
DO NOT EAT, DRINK OR SMOKE IN THIS AREA
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to lead conducted pursuant to paragraph (d) of this section.
The information contained in the appendices to this section is not intended by itself, to create any additional obligations not otherwise imposed by this standard nor detract from any existing obligation.
Appendix A to § 1910.1025—Substance Data Sheet for Occupational Exposure to Lead
i. Substance Identification
A. Substance: Pure lead (Pb) is a heavy metal at room temperature and pressure and is a basic chemical element. It can combine with various other substances to form numerous lead compounds.
B. Compounds Covered by the Standard: The word “lead” when used in this standard means elemental lead, all inorganic lead compounds and a class of organic lead compounds called lead soaps. This standard does not apply to other organic lead compounds.
C. Uses: Exposure to lead occurs in at least 120 different occupations, including primary and secondary lead smelting, lead storage battery manufacturing, lead pigment manufacturing and use, solder manufacturing and use, shipbuilding and ship repairing, auto manufacturing, and printing.
D. Permissible Exposure: The Permissible Exposure Limit (PEL) set by the standard is 50 micrograms of lead per cubic meter of air (50 µg/m 3 ), averaged over an 8-hour workday.
E. Action Level: The standard establishes an action level of 30 micrograms per cubic meter of air (30 µg/m 3 ), time weighted average, based on an 8-hour work-day. The action level initiates several requirements of the standard, such as exposure monitoring, medical surveillance, and training and education.
ii. health hazard data
A. Ways in which lead enters your body. When absorbed into your body in certain doses lead is a toxic substance. The object of the lead standard is to prevent absorption of harmful quantities of lead. The standard is intended to protect you not only from the immediate toxic effects of lead, but also from the serious toxic effects that may not become apparent until years of exposure have passed.
Lead can be absorbed into your body by inhalation (breathing) and ingestion (eating). Lead (except for certain organic lead compounds not covered by the standard, such as tetraethyl lead) is not absorbed through your skin. When lead is scattered in the air as a dust, fume or mist it can be inhaled and absorbed through you lungs and upper respiratory tract. Inhalation of airborne lead is generally the most important source of occupational lead absorption. You can also absorb lead through your digestive system if lead gets into your mouth and is swallowed. If you handle food, cigarettes, chewing tobacco, or make-up which have lead on them or handle them with hands contaminated with lead, this will contribute to ingestion.
A significant portion of the lead that you inhale or ingest gets into your blood stream. Once in your blood stream, lead is circulated throughout your body and stored in various organs and body tissues. Some of this lead is quickly filtered out of your body and excreted, but some remains in the blood and other tissues. As exposure to lead continues, the amount stored in your body will increase if you are absorbing more lead than your body is excreting. Even though you may not be aware of any immediate symptoms of disease, this lead stored in your tissues can be slowly causing irreversible damage, first to individual cells, then to your organs and whole body systems.
B. Effects of overexposure to lead —
Lead is a potent, systemic poison that serves no known useful function once absorbed by your body. Taken in large enough doses, lead can kill you in a matter of days. A condition affecting the brain called acute encephalopathy may arise which develops quickly to seizures, coma, and death from cardiorespiratory arrest. A short term dose of lead can lead to acute encephalopathy. Short term occupational exposures of this magnitude are highly unusual, but not impossible. Similar forms of encephalopathy may, however, arise from extended, chronic exposure to lower doses of lead. There is no sharp dividing line between rapidly developing acute effects of lead, and chronic effects which take longer to acquire. Lead adversely affects numerous body systems, and causes forms of health impairment and disease which arise after periods of exposure as short as days or as long as several years.
Chronic overexposure to lead may result in severe damage to your blood-forming, nervous, urinary and reproductive systems. Some common symptoms of chronic overexposure include loss of appetite, metallic taste in the mouth, anxiety, constipation, nausea, pallor, excessive tiredness, weakness, insomnia, headache, nervous irritability, muscle and joint pain or soreness, fine tremors, numbness, dizziness, hyperactivity and colic. In lead colic there may be severe abdominal pain.
Damage to the central nervous system in general and the brain (encephalopathy) in particular is one of the most severe forms of lead poisoning. The most severe, often fatal, form of encephalopathy may be preceded by vomiting, a feeling of dullness progressing to drowsiness and stupor, poor memory, restlessness, irritability, tremor, and convulsions. It may arise suddenly with the onset of seizures, followed by coma, and death. There is a tendency for muscular weakness to develop at the same time. This weakness may progress to paralysis often observed as a characteristic “wrist drop” or “foot drop” and is a manifestation of a disease to the nervous system called peripheral neuropathy.
Chronic overexposure to lead also results in kidney disease with few, if any, symptoms appearing until extensive and most likely permanent kidney damage has occurred. Routine laboratory tests reveal the presence of this kidney disease only after about two-thirds of kidney function is lost. When overt symptoms of urinary dysfunction arise, it is often too late to correct or prevent worsening conditions, and progression to kidney dialysis or death is possible.
Chronic overexposure to lead impairs the reproductive systems of both men and women. Overexposure to lead may result in decreased sex drive, impotence and sterility in men. Lead can alter the structure of sperm cells raising the risk of birth defects. There is evidence of miscarriage and stillbirth in women whose husbands were exposed to lead or who were exposed to lead themselves. Lead exposure also may result in decreased fertility, and abnormal menstrual cycles in women. The course of pregnancy may be adversely affected by exposure to lead since lead crosses the placental barrier and poses risks to developing fetuses. Children born of parents either one of whom were exposed to excess lead levels are more likely to have birth defects, mental retardation, behavioral disorders or die during the first year of childhood.
Overexposure to lead also disrupts the blood-forming system resulting in decreased hemoglobin (the substance in the blood that carries oxygen to the cells) and ultimately anemia. Anemia is characterized by weakness, pallor and fatigability as a result of decreased oxygen carrying capacity in the blood.
Prevention of adverse health effects for most workers from exposure to lead throughout a working lifetime requires that worker blood lead (PbB) levels be maintained at or below forty micrograms per one hundred grams of whole blood (40 µg/100g). The blood lead levels of workers (both male and female workers) who intend to have children should be maintained below 30 µg/100g to minimize adverse reproductive health effects to the parents and to the developing fetus.
The measurement of your blood lead level is the most useful indicator of the amount of lead being absorbed by your body. Blood lead levels (PbB) are most often reported in units of milligrams (mg) or micrograms (µg) of lead (1 mg = 1000 µg) per 100 grams (100g), 100 milliters (100 ml) or deciliter (dl) of blood. These three units are essentially the same. Sometime PbB's are expressed in the form of mg% or µg%. This is a shorthand notation for 100g, 100 ml, or dl.
PbB measurements show the amount of lead circulating in your blood stream, but do not give any information about the amount of lead stored in your various tissues. PbB measurements merely show current absorption of lead, not the effect that lead is having on your body or the effects that past lead exposure may have already caused. Past research into lead-related diseases, however, has focused heavily on associations between PbBs and various diseases. As a result, your PbB is an important indicator of the likelihood that you will gradually acquire a lead-related health impairment or disease.
Once your blood lead level climbs above 40 µg/100g, your risk of disease increases. There is a wide variability of individual response to lead, thus it is difficult to say that a particular PbB in a given person will cause a particular effect. Studies have associated fatal encephalopathy with PbBs as low as 150 µg/100g. Other studies have shown other forms of diseases in some workers with PbBs well below 80 µg/100g. Your PbB is a crucial indicator of the risks to your health, but one other factor is also extremely important. This factor is the length of time you have had elevated PbBs. The longer you have an elevated PbB, the greater the risk that large quantities of lead are being gradually stored in your organs and tissues (body burden). The greater your overall body burden, the greater the chances of substantial permanent damage.
The best way to prevent all forms of lead-related impairments and diseases—both short term and long term- is to maintain your PbB below 40 µg/100g. The provisions of the standard are designed with this end in mind. Your employer has prime responsibility to assure that the provisions of the standard are complied with both by the company and by individual workers. You as a worker, however, also have a responsibility to assist your employer in complying with the standard. You can play a key role in protecting your own health by learning about the lead hazards and their control, learning what the standard requires, following the standard where it governs your own actions, and seeing that your employer complies with provisions governing his actions.
You should immediately notify your employer if you develop signs or symptoms associated with lead poisoning or if you desire medical advice concerning the effects of current or past exposure to lead on your ability to have a healthy child. You should also notify your employer if you have difficulty breathing during a respirator fit test or while wearing a respirator. In each of these cases your employer must make available to you appropriate medical examinations or consultations. These must be provided at no cost to you and at a reasonable time and place.
The standard contains a procedure whereby you can obtain a second opinion by a physician of your choice if the employer selected the initial physician.
Appendix B to § 1910.1025—Employee Standard Summary
This appendix summarizes key provisions of the standard that you as a worker should become familiar with.
i. permissible exposure limit (pel)—paragraph ( c )
The standards sets a permissible exposure limit (PEL) of fifty micrograms of lead per cubic meter of air (50 µg/m 3 ), averaged over an 8-hour work-day. This is the highest level of lead in air to which you may be permissibly exposed over an 8-hour workday. Since it is an 8-hour average it permits short exposures above the PEL so long as for each 8-hour work day your average exposure does not exceed the PEL.
This standard recognizes that your daily exposure to lead can extend beyond a typical 8-hour workday as the result of overtime or other alterations in your work schedule. To deal with this, the standard contains a formula which reduces your permissible exposure when you are exposed more than 8 hours. For example, if you are exposed to lead for 10 hours a day, the maximum permitted average exposure would be 40 µg/m 3.
ii. exposure monitoring—paragraph ( d )
If lead is present in the workplace where you work in any quantity, your employer is required to make an initial determination of whether the action level is exceeded for any employee. This initial determination must include instrument monitoring of the air for the presence of lead and must cover the exposure of a representative number of employees who are reasonably believed to have the highest exposure levels. If your employer has conducted appropriate air sampling for lead in the past year he may use these results. If there have been any employee complaints of symptoms which may be attributable to exposure to lead or if there is any other information or observations which would indicate employee exposure to lead, this must also be considered as part of the initial determination. This initial determination must have been completed by March 31, 1979. If this initial determination shows that a reasonable possibility exists that any employee may be exposed, without regard to respirators, over the action level (30 µg/m 3 ) your employer must set up an air monitoring program to determine the exposure level of every employee exposed to lead at your workplace.
In carrying out this air monitoring program, your employer is not required to monitor the exposure of every employee, but he must monitor a representative number of employees and job types. Enough sampling must be done to enable each employee's exposure level to be reasonably least one full shift (at least 7 hours) air sample. In addition, these air samples must be taken under conditions which represent each employee's regular, daily exposure to lead. All initial exposure monitoring must have been completed by May 30, 1979.
If you are exposed to lead and air sampling is performed, your employer is required to quickly notify you in writing of air monitoring results which represent your exposure. If the results indicate your exposure exceeds the PEL (without regard to your use of respirators), then your employer must also notify you of this in writing, and provide you with a description of the corrective action that will be taken to reduce your exposure.
Your exposure must be rechecked by monitoring every six months if your exposure is over the action level but below the PEL. Air monitoring must be repeated every 3 months if you are exposed over the PEL. Your employer may discontinue monitoring for you if 2 consecutive measurements, taken at least two weeks apart, are below the action level. However, whenever there is a production, process, control, or personnel change at your workplace which may result in new or additional exposure to lead, or whenever there is any other reason to suspect a change which may result in new or additional exposure to lead, your employer must perform additional monitoring.
iii. methods of compliance—paragraph ( e )
Your employer is required to assure that no employee is exposed to lead in excess of the PEL. The standard establishes a priority of methods to be used to meet the PEL.
iv. respiratory protection—paragraph ( f )
Your employer is required to provide and assure your use of respirators when your exposure to lead is not controlled below the PEL by other means. The employer must pay the cost of the respirator. Whenever you request one, your employer is also required to provide you a respirator even if your air exposure level does not exceed the PEL. You might desire a respirator when, for example, you have received medical advice that your lead absorption should be decreased. Or, you may intend to have children in the near future, and want to reduce the level of lead in your body to minimize adverse reproductive effects. While respirators are the least satisfactory means of controlling your exposure, they are capable of providing significant protection if properly chosen, fitted, worn, cleaned, maintained, and replaced when they stop providing adequate protection.
Your employer is required to select respirators from the seven types listed in Table II of the Respiratory Protection section of the standard (§ 1910.1025(f)). Any respirator chosen must be approved by the National Institute for Occupational Safety and Health (NIOSH) under the provisions of 42 CFR part 84. This respirator selection table will enable your employer to choose a type of respirator that will give you a proper amount of protection based on your airborne lead exposure. Your employer may select a type of respirator that provides greater protection than that required by the standard; that is, one recommended for a higher concentration of lead than is present in your workplace. For example, a powered air-purifying respirator (PAPR) is much more protective than a typical negative pressure respirator, and may also be more comfortable to wear. A PAPR has a filter, cartridge, or canister to clean the air, and a power source that continuously blows filtered air into your breathing zone. Your employer might make a PAPR available to you to ease the burden of having to wear a respirator for long periods of time. The standard provides that you can obtain a PAPR upon request.
Your employer must also start a Respiratory Protection Program. This program must include written procedures for the proper selection, use, cleaning, storage, and maintenance of respirators.
Your employer must ensure that your respirator facepiece fits properly. Proper fit of a respirator facepiece is critical to your protection from airborne lead. Obtaining a proper fit on each employee may require your employer to make available several different types of respirator masks. To ensure that your respirator fits properly and that facepiece leakage is minimal, your employer must give you either a qualitative or quantitative fit test as specified in appendix A of the Respiratory Protection standard located at 29 CFR 1910.134.
You must also receive from your employer proper training in the use of respirators. Your employer is required to teach you how to wear a respirator, to know why it is needed, and to understand its limitations.
The standard provides that if your respirator uses filter elements, you must be given an opportunity to change the filter elements whenever an increase in breathing resistance is detected. You also must be permitted to periodically leave your work area to wash your face and respirator facepiece whenever necessary to prevent skin irritation. If you ever have difficulty in breathing during a fit test or while using a respirator, your employer must make a medical examination available to you to determine whether you can safely wear a respirator. The result of this examination may be to give you a positive pressure respirator (which reduces breathing resistance) or to provide alternative means of protection.
v. protective work clothing and equipment—paragraph ( g )
If you are exposed to lead above the PEL, or if you are exposed to lead compounds such as lead arsenate or lead azide which can cause skin and eye irritation, your employer must provide you with protective work clothing and equipment appropriate for the hazard. If work clothing is provided, it must be provided in a clean and dry condition at least weekly, and daily if your airborne exposure to lead is greater than 200 µg/m 3. Appropriate protective work clothing and equipment can include coveralls or similar full-body work clothing, gloves, hats, shoes or disposable shoe coverlets, and face shields or vented goggles. Your employer is required to provide all such equipment at no cost to you. He is responsible for providing repairs and replacement as necessary, and also is responsible for the cleaning, laundering or disposal of protective clothing and equipment. Contaminated work clothing or equipment must be removed in change rooms and not worn home or you will extend your exposure and expose your family since lead from your clothing can accumulate in your house, car, etc. Contaminated clothing which is to be cleaned, laundered or disposed of must be placed in closed containers in the change room. At no time may lead be removed from protective clothing or equipment by any means which disperses lead into the workroom air.
vi. housekeeping—paragraph ( h )
Your employer must establish a housekeeping program sufficient to maintain all surfaces as free as practicable of accumulations of lead dust. Vacuuming is the preferred method of meeting this requirement, and the use of compressed air to clean floors and other surfaces is absolutely prohibited. Dry or wet sweeping, shoveling, or brushing may not be used except where vaccuming or other equally effective methods have been tried and do not work. Vacuums must be used and emptied in a manner which minimizes the reentry of lead into the workplace.
vii. hygiene facilities and practices—paragraph ( i )
The standard requires that change rooms, showers, and filtered air lunchrooms be constructed and made available to workers exposed to lead above the PEL. When the PEL is exceeded the employer must assure that food and beverage is not present or consumed, tobacco products are not present or used, and cosmetics are not applied, except in these facilities. Change rooms, showers, and lunchrooms, must be used by workers exposed in excess of the PEL. After showering, no clothing or equipment worn during the shift may be worn home, and this includes shoes and underwear. Your own clothing worn during the shift should be carried home and cleaned carefully so that it does not contaminate your home. Lunchrooms may not be entered with protective clothing or equipment unless surface dust has been removed by vacuuming, downdraft booth, or other cleaning method. Finally, workers exposed above the PEL must wash both their hands and faces prior to eating, drinking, smoking or applying cosmetics.
All of the facilities and hygiene practices just discussed are essential to minimize additional sources of lead absorption from inhalation or ingestion of lead that may accumulate on you, your clothes, or your possessions. Strict compliance with these provisions can virtually eliminate several sources of lead exposure which significantly contribute to excessive lead absorption.
viii. medical surveillance—paragraph ( j )
The medical surveillance program is part of the standard's comprehensive approach to the prevention of lead-related disease. Its purpose is to supplement the main thrust of the standard which is aimed at minimizing airborne concentrations of lead and sources of ingestion. Only medical surveillance can determine if the other provisions of the standard have affectively protected you as an individual. Compliance with the standard's provision will protect most workers from the adverse effects of lead exposure, but may not be satisfactory to protect individual workers (1) who have high body burdens of lead acquired over past years, (2) who have additional uncontrolled sources of non-occupational lead exposure, (3) who exhibit unusual variations in lead absorption rates, or (4) who have specific non-work related medical conditions which could be aggravated by lead exposure (e.g., renal disease, anemia). In addition, control systems may fail, or hygiene and respirator programs may be inadequate. Periodic medical surveillance of individual workers will help detect those failures. Medical surveillance will also be important to protect your reproductive ability—regardless of whether you are a man or woman.
All medical surveillance required by the standard must be performed by or under the supervision of a licensed physician. The employer must provide required medical surveillance without cost to employees and at a reasonable time and place. The standard's medical surveillance program has two parts-periodic biological monitoring and medical examinations.
Your employer's obligation to offer you medical surveillance is triggered by the results of the air monitoring program. Medical surveillance must be made available to all employees who are exposed in excess of the action level for more than 30 days a year. The initial phase of the medical surveillance program, which includes blood lead level tests and medical examinations, must be completed for all covered employees no later than August 28, 1979. Priority within this first round of medical surveillance must be given to employees whom the employer believes to be at greatest risk from continued exposure (for example, those with the longest prior exposure to lead, or those with the highest current exposure). Thereafter, the employer must periodically make medical surveillance—both biological monitoring and medical examinations—available to all covered employees.
Biological monitoring under the standard consists of blood lead level (PbB) and zinc protoporphyrin tests at least every 6 months after the initial PbB test. A zinc protoporphyrin (ZPP) test is a very useful blood test which measures an effect of lead on your body. Thus biological monitoring under the standard is currently limited to PbB testing. If a worker's PbB exceeds 40 µg/100g the monitoring frequency must be increased from every 6 months to at least every 2 months and not reduced until two consecutive PbBs indicate a blood lead level below 40 µg/100g. Each time your PbB is determined to be over 40 µg/100g, your employer must notify you of this in writing within five working days of his receipt of the test results. The employer must also inform you that the standard requires temporary medical removal with economic protection when your PbB exceeds certain criteria. (See Discussion of Medical Removal Protection—Paragraph (k).) During the first year of the standard, this removal criterion is 80 µg/100g. Anytime your PbB exceeds 80 µg/100g your employer must make available to you a prompt follow-up PbB test to ascertain your PbB. If the two tests both exceed 80 µg/100g and you are temporarily removed, then your employer must make successive PbB tests available to you on a monthly basis during the period of your removal.
Medical examinations beyond the initial one must be made available on an annual basis if your blood lead level exceeds 40 µg/100g at any time during the preceding year. The initial examination will provide information to establish a baseline to which subsequent data can be compared. An initial medical examination must also be made available (prior to assignment) for each employee being assigned for the first time to an area where the airborne concentration of lead equals or exceeds the action level. In addition, a medical examination or consultation must be made available as soon as possible if you notify your employer that you are experiencing signs or symptoms commonly associated with lead poisoning or that you have difficulty breathing while wearing a respirator or during a respirator fit test. You must also be provided a medical examination or consultation if you notify your employer that you desire medical advice concerning the effects of current or past exposure to lead on your ability to procreate a healthy child.
Finally, appropriate follow-up medical examinations or consultations may also be provided for employees who have been temporarily removed from exposure under the medical removal protection provisions of the standard. (See part IX, below.)
The standard specifies the minimum content of pre-assignment and annual medical examinations. The content of other types of medical examinations and consultations is left up to the sound discretion of the examining physician. Pre-assignment and annual medical examinations must include (1) a detailed work history and medical history, (2) a thorough physical examination, and (3) a series of laboratory tests designed to check your blood chemistry and your kidney function. In addition, at any time upon your request, a laboratory evaluation of male fertility will be made (microscopic examination of a sperm sample), or a pregnancy test will be given.
The standard does not require that you participate in any of the medical procedures, tests, etc. which your employer is required to make available to you. Medical surveillance can, however, play a very important role in protecting your health. You are strongly encouraged, therefore, to participate in a meaningful fashion. The standard contains a multiple physician review mechanism which would give you a chance to have a physician of your choice directly participate in the medical surveillance program. If you were dissatisfied with an examination by a physician chosen by your employer, you could select a second physician to conduct an independent analysis. The two doctors would attempt to resolve any differences of opinion, and select a third physician to resolve any firm dispute. Generally your employer will choose the physician who conducts medical surveillance under the lead standard—unless you and your employer can agree on the choice of a physician or physicians. Some companies and unions have agreed in advance, for example, to use certain independent medical laboratories or panels of physicians. Any of these arrangements are acceptable so long as required medical surveillance is made available to workers.
The standard requires your employer to provide certain information to a physician to aid in his or her examination of you. This information includes (1) the standard and its appendices, (2) a description of your duties as they relate to lead exposure, (3) your exposure level, (4) a description of personal protective equipment you wear, (5) prior blood lead level results, and (6) prior written medical opinions concerning you that the employer has. After a medical examination or consultation the physician must prepare a written report which must contain (1) the physician's opinion as to whether you have any medical condition which places you at increased risk of material impairment to health from exposure to lead, (2) any recommended special protective measures to be provided to you, (3) any blood lead level determinations, and (4) any recommended limitation on your use of respirators. This last element must include a determination of whether you can wear a powered air purifying respirator (PAPR) if you are found unable to wear a negative pressure respirator.
The medical surveillance program of the lead standard may at some point in time serve to notify certain workers that they have acquired a disease or other adverse medical condition as a result of occupational lead exposure. If this is true, these workers might have legal rights to compensation from public agencies, their employers, firms that supply hazardous products to their employers, or other persons. Some states have laws, including worker compensation laws, that disallow a worker who learns of a job-related health impairment to sue, unless the worker sues within a short period of time after learning of the impairment. (This period of time may be a matter of months or years.) An attorney can be consulted about these possibilities. It should be stressed that OSHA is in no way trying to either encourage or discourage claims or lawsuits. However, since results of the standard's medical surveillance program can significantly affect the legal remedies of a worker who has acquired a job-related disease or impairment, it is proper for OSHA to make you aware of this.
The medical surveillance section of the standard also contains provisions dealing with chelation. Chelation is the use of certain drugs (administered in pill form or injected into the body) to reduce the amount of lead absorbed in body tissues. Experience accumulated by the medical and scientific communities has largely confirmed the effectiveness of this type of therapy for the treatment of very severe lead poisoning. On the other hand, it has also been established that there can be a long list of extremely harmful side effects associated with the use of chelating agents. The medical community has balanced the advantages and disadvantages resulting from the use of chelating agents in various circumstances and has established when the use of these agents is acceptable. The standard includes these accepted limitations due to a history of abuse of chelation therapy by some lead companies. The most widely used chelating agents are calcium disodium EDTA, (Ca Na 2 EDTA), Calcium Disodium Versenate (Versenate), and d-penicillamine (pencillamine or Cupramine).
The standard prohibits “prophylactic chelation” of any employee by any person the employer retains, supervises or controls. “Prophylactic chelation” is the routine use of chelating or similarly acting drugs to prevent elevated blood levels in workers who are occupationally exposed to lead, or the use of these drugs to routinely lower blood lead levels to predesignated concentrations believed to be ‘safe’. It should be emphasized that where an employer takes a worker who has no symptoms of lead poisoning and has chelation carried out by a physician (either inside or outside of a hospital) solely to reduce the worker's blood lead level, that will generally be considered prophylactic chelation. The use of a hospital and a physician does not mean that prophylactic chelation is not being performed. Routine chelation to prevent increased or reduce current blood lead levels is unacceptable whatever the setting.
The standard allows the use of “therapeutic” or “diagnostic” chelation if administered under the supervision of a licensed physician in a clinical setting with thorough and appropriate medical monitoring. Therapeutic chelation responds to severe lead poisoning where there are marked symptoms. Diagnostic chelation involved giving a patient a dose of the drug then collecting all urine excreted for some period of time as an aid to the diagnosis of lead poisoning.
In cases where the examining physician determines that chelation is appropriate, you must be notified in writing of this fact before such treatment. This will inform you of a potentially harmful treatment, and allow you to obtain a second opinion.
ix. medical removal protection—paragraph ( k )
Excessive lead absorption subjects you to increased risk of disease. Medical removal protection (MRP) is a means of protecting you when, for whatever reasons, other methods, such as engineering controls, work practices, and respirators, have failed to provide the protection you need. MRP involves the temproary removal of a worker from his or her regular job to a place of significantly lower exposure without any loss of earnings, seniority, or other employment rights or benefits. The purpose of this program is to cease further lead absorption and allow your body to naturally excrete lead which has previously been absorbed. Temporary medical removal can result from an elevated blood lead level, or a medical opinion. Up to 18 months of protection is provided as a result of either form of removal. The vast majority of removed workers, however, will return to their former jobs long before this eighteen month period expires. The standard contains special provisions to deal with the extraordinary but possible case where a longterm worker's blood lead level does not adequately decline during eighteen months of removal.
During the first year of the standard, if your blood lead level is 80 µg/100g or above you must be removed from any exposure where your air lead level without a respirator would be 100 µg/m 3 or above. If you are removed from your normal job you may not be returned until your blood lead level declines to at least 60 µg/100g. These criteria for removal and return will change according to the following schedule:
| Removal blood lead (µg/100 g) | Air lead (µg/m 3 ) | Return blood lead (µg/100 g) | |
|---|---|---|---|
| After Mar. 1, 1980 | 70 and above | 50 and above | At or below 50. |
| After Mar. 1, 1981 | 60 and above | 30 and above | At or below 40. |
| After Mar. 1, 1983 | 50 and above averaged over six months | 30 and above | Do. |
You may also be removed from exposure even if your blood lead levels are below these criteria if a final medical determination indicates that you temporarily need reduced lead exposure for medical reasons. If the physician who is implementing your employers medical program makes a final written opinion recommending your removal or other special protective measures, your employer must implement the physician's recommendation. If you are removed in this manner, you may only be returned when the doctor indicates that it is safe for you to do so.
The standard does not give specific instructions dealing with what an employer must do with a removed worker. Your job assignment upon removal is a matter for you, your employer and your union (if any) to work out consistent with existing procedures for job assignments. Each removal must be accomplished in a manner consistent with existing collective bargaining relationships. Your employer is given broad discretion to implement temporary removals so long as no attempt is made to override existing agreements. Similarly, a removed worker is provided no right to veto an employer's choice which satisfies the standard.
In most cases, employers will likely transfer removed employees to other jobs with sufficiently low lead exposure. Alternatively, a worker's hours may be reduced so that the time weighted average exposure is reduced, or he or she may be temporarily laid off if no other alternative is feasible.
In all of these situation, MRP benefits must be provided during the period of removal—i.e., you continue to receive the same earnings, seniority, and other rights and benefits you would have had if you had not been removed. Earnings includes more than just your base wage; it includes overtime, shift differentials, incentives, and other compensation you would have earned if you had not been removed. During the period of removal you must also be provided with appropriate follow-up medical surveillance. If you were removed because your blood lead level was too high, you must be provided with a monthly blood test. If a medical opinion caused your removal, you must be provided medical tests or examinations that the doctor believes to be appropriate. If you do not participate in this follow up medical surveillance, you may lose your eligibility for MRP benefits.
When you are medically eligible to return to your former job, your employer must return you to your “former job status.” This means that you are entitled to the position, wages, benefits, etc., you would have had if you had not been removed. If you would still be in your old job if no removal had occurred that is where you go back. If not, you are returned consistent with whatever job assignment discretion your employer would have had if no removal had occurred. MRP only seeks to maintain your rights, not expand them or diminish them.
If you are removed under MRP and you are also eligible for worker compensation or other compensation for lost wages, your employer's MRP benefits obligation is reduced by the amount that you actually receive from these other sources. This is also true if you obtain other employment during the time you are laid off with MRP benefits.
The standard also covers situations where an employer voluntarily removes a worker from exposure to lead due to the effects of lead on the employee's medical condition, even though the standard does not require removal. In these situations MRP benefits must still be provided as though the standard required removal. Finally, it is important to note that in all cases where removal is required, respirators cannot be used as a substitute. Respirators may be used before removal becomes necessary, but not as an alternative to a transfer to a low exposure job, or to a lay-off with MRP benefits.
x. employee information and training—paragraph ( l )
Your employer is required to provide an information and training program for all employees exposed to lead above the action level or who may suffer skin or eye irritation from lead. This program must inform these employees of the specific hazards associated with their work environment, protective measures which can be taken, the danger of lead to their bodies (including their reproductive systems), and their rights under the standard. In addition your employer must make readily available to all employees, including those exposed below the action level, a copy of the standard and its appendices and must distribute to all employees any materials provided to the employer by the Occupational Safety and Health Administration (OSHA).
Your employer is required to complete this training program for all employees by August 28, 1979. After this date, all new employees must be trained prior to initial assignment to areas where there is a possibility of exposure over the action level.
This training program must also be provided at least annually thereafter.
xi. SIGNS—PARAGRAPH (m)
The standard requires that the following warning sign be posted in the work areas when the exposure to lead exceeds the PEL:
DANGER
LEAD
MAY DAMAGE FERTILITY OR THE UNBORN CHILD
CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM
DO NOT EAT, DRINK OR SMOKE IN THIS AREA
However, prior to June 1, 2016, employers may use the following legend in lieu of that specified above:
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
xii. recordkeeping—paragraph ( n )
Your employer is required to keep all records of exposure monitoring for airborne lead. These records must include the name and job classification of employees measured, details of the sampling and analytic techniques, the results of this sampling, and the type of respiratory protection being worn by the person sampled. Your employer is also required to keep all records of biological monitoring and medical examination results. These must include the names of the employees, the physician's written opinion, and a copy of the results of the examination. All of the above kinds of records must be kept for 40 years, or for at least 20 years after your termination of employment, whichever is longer.
Recordkeeping is also required if you are temporarily removed from your job under the medical removal protection program. This record must include your name, the date of your removal and return, how the removal was or is being accomplished, and whether or not the reason for the removal was an elevated blood lead level. Your employer is required to keep each medical removal record only for as long as the duration of an employee's employment.
The standard requires that if you request to see or copy environmental monitoring, blood lead level monitoring, or medical removal records, they must be made available to you or to a representative that you authorize. Your union also has access to these records. Medical records other than PbB's must also be provided upon request to you, to your physician or to any other person whom you may specifically designate. Your union does not have access to your personal medical records unless you authorize their access.
xiii. observations of monitoring—paragraph ( o )
When air monitoring for lead is performed at your workplace as required by this standard, your employer must allow you or someone you designate to act as an observer of the monitoring. Observers are entitled to an explanation of the measurement procedure, and to record the results obtained. Since results will not normally be available at the time of the monitoring, observers are entitled to record or receive the results of the monitoring when returned by the laboratory. Your employer is required to provide the observer with any personal protective devices required to be worn by employees working in the area that is being monitored. The employer must require the observer to wear all such equipment and to comply with all other applicable safety and health procedures.
xiv. for additional information
A. Copies of the Standard and explanatory material may be obtained by writing or calling the OSHA Docket Office, U.S. Department of Labor, room N2634, 200 Constitution Avenue, N.W., Washington, DC 20210. Telephone: (202) 219-7894.
1. The standard and summary of the statement of reasons (preamble), Federal Register, Volume 43, pp. 52952-53014, November 14, 1978.
2. The full statement of reasons (preamble) Federal Register, vol. 43, pp. 54354-54509, November 21, 1978.
3. Partial Administrative Stay and Corrections to the standard, (44 FR 5446-5448) January 26, 1979.
4. Notice of the Partial Judicial Stay (44 FR 14554-14555) March 13, 1979.
5. Corrections to the preamble, Federal Register, vol. 44, pp. 20680-20681, April 6, 1979.
6. Additional correction to the preamble concerning the construction industry, Federal Register, vol. 44, p. 50338, August 28, 1979.
7. Appendices to the standard (Appendices A, B, C), Federal Register, Vol. 44, pp. 60980-60995, October 23, 1979.
8. Corrections to appendices, Federal Register, Vol. 44, 68828, November 30, 1979.
9. Revision to the standard and an additional appendix (Appendix D), Federal Register, Vol. 47, pp. 51117-51119, November 12, 1982.
10. Notice of reopening of lead rulemaking for nine remand industry sectors, Federal Register, vol. 53, pp. 11511-11513, April 7, 1988.
11. Statement of reasons, Federal Register, vol. 54, pp. 29142-29275, July 11, 1989.
12. Statement of reasons, Federal Register, vol. 55, pp. 3146-3167, January 30, 1990.
13. Correction to appendix B, Federal Register, vol. 55, pp. 4998-4999, February 13, 1991.
14. Correction to appendices, Federal Register, vol. 56, p. 24686, May 31, 1991.
B. Additional information about the standard, its enforcement, and your employer's compliance can be obtained from the nearest OSHA Area Office listed in your telephone directory under United States Government/Department of Labor.
Appendix C to § 1910.1025—Medical Surveillance Guidelines
introduction
The primary purpose of the Occupational Safety and Health Act of 1970 is to assure, so far as possible, safe and healthful working conditions for every working man and woman. The occupational health standard for inorganic lead 1 was promulgated to protect workers exposed to inorganic lead including metallic lead, all inorganic lead compounds and organic lead soaps.
1 The term inorganic lead used throughout the medical surveillance appendices is meant to be synonymous with the definition of lead set forth in the standard.
Under this final standard in effect as of March 1, 1979, occupational exposure to inorganic lead is to be limited to 50 µg/m 3 (micrograms per cubic meter) based on an 8 hour time-weighted average (TWA). This level of exposure eventually must be achieved through a combination of engineering, work practice and other administrative controls. Periods of time ranging from 1 to 10 years are provided for different industries to implement these controls. The schedule which is based on individual industry considerations is given in Table 1. Until these controls are in place, respirators must be used to meet the 50 µg/m 3 exposure limit.
The standard also provides for a program of biological monitoring and medical surveillance for all employees exposed to levels of inorganic lead above the action level of 30 µg/m 3 (TWA) for more than 30 days per year.
The purpose of this document is to outline the medical surveillance provisions of the standard for inorganic lead, and to provide further information to the physician regarding the examination and evaluation of workers exposed to inorganic lead.
Section 1 provides a detailed description of the monitoring procedure including the required frequency of blood testing for exposed workers, provisions for medical removal protection (MRP), the recommended right of the employee to a second medical opinion, and notification and recordkeeping requirements of the employer. A discussion of the requirements for respirator use and respirator monitoring and OSHA's position on prophylactic chelation therapy are also included in this section.
Section 2 discusses the toxic effects and clinical manifestations of lead poisoning and effects of lead intoxication on enzymatic pathways in heme synthesis. The adverse effects on both male and female reproductive capacity and on the fetus are also discussed.
Section 3 outlines the recommended medical evaluation of the worker exposed to inorganic lead including details of the medical history, physical examination, and recommended laboratory tests, which are based on the toxic effects of lead as discussed in Section 2.
Section 4 provides detailed information concerning the laboratory tests available for the monitoring of exposed workers. Included also is a discussion of the relative value of each test and the limitations and precautions which are necessary in the interpretation of the laboratory results.
| Permissible airborne lead levels by industry (µg/m 3 ) 1 | Effective date | |||||
|---|---|---|---|---|---|---|
| Mar. 1, 1979 | Mar. 1, 1980 | Mar. 1, 1981 | Mar. 1, 1982 | Mar. 1, 1984 | Mar. 1, 1989 (final) | |
| 1. Primary lead production | 200 | 200 | 200 | 100 | 100 | 50 |
| 2. Secondary lead production | 200 | 200 | 200 | 100 | 50 | 50 |
| 3. Lead-acid battery manufacturing | 200 | 200 | 100 | 100 | 50 | 50 |
| 4. Nonferrous foundries | 200 | 100 | 100 | 100 | 50 | 50 |
| 5. Lead pigment manufacturing | 200 | 200 | 200 | 100 | 50 | 50 |
| 6. All other industries | 200 | 50 | 50 | 50 | 50 | 50 |
| 1 Airborne levels to be achieved without reliance or respirator protection through a combination of engineering, work practice and other administrative controls. While these controls are being implemented respirators must be used to meet the 50 µg/m 3 exposure limit. |
i. medical surveillance and monitoring requirements for workers exposed to inorganic lead
Under the occupational health standard for inorganic lead, a program of biological monitoring and medical surveillance is to be made available to all employees exposed to lead above the action level of 30 µg/m 3 TWA for more than 30 days each year. This program consists of periodic blood sampling and medical evaluation to be performed on a schedule which is defined by previous laboratory results, worker complaints or concerns, and the clinical assessment of the examining physician.
Under this program, the blood lead level of all employees who are exposed to lead above the action level of 30 µg/m 3 is to be determined at least every six months. The frequency is increased to every two months for employees whose last blood lead level was between 40 µg/100 g whole blood and the level requiring employee medical removal to be discussed below. For employees who are removed from exposure to lead due to an elevated blood lead, a new blood lead level must be measured monthly. A zinc protoporphyrin (ZPP) is required on each occasion that a blood lead level measurement is made.
An annual medical examination and consultation performed under the guidelines discussed in Section 3 is to be made available to each employee for whom a blood test conducted at any time during the preceding 12 months indicated a blood lead level at or above 40 µg/100 g. Also, an examination is to be given to all employees prior to their assignment to an area in which airborne lead concentrations reach or exceed the action level. In addition, a medical examination must be provided as soon as possible after notification by an employee that the employee has developed signs or symptoms commonly associated with lead intoxication, that the employee desires medical advice regarding lead exposure and the ability to procreate a healthy child, or that the employee has demonstrated difficulty in breathing during a respirator fitting test or during respirator use. An examination is also to be made available to each employee removed from exposure to lead due to a risk of sustaining material impairment to health, or otherwise limited or specially protected pursuant to medical recommendations.
Results of biological monitoring or the recommendations of an examining physician may necessitate removal of an employee from further lead exposure pursuant to the standard's medical removal protection (MRP) program. The object of the MRP program is to provide temporary medical removal to workers either with substantially elevated blood lead levels or otherwise at risk of sustaining material health impairment from continued substantial exposure to lead. The following guidelines which are summarized in Table 2 were created under the standard for the temporary removal of an exposed employee and his or her subsequent return to work in an exposure area.
| Effective date | |||||
|---|---|---|---|---|---|
| Mar. 1, 1979 | Mar. 1, 1980 | Mar. 1, 1981 | Mar. 1, 1982 | Mar. 1, 1983 (final) | |
| A. Blood lead level requiring employee medical removal. (Level must be confirmed with second follow-up blood lead level within two weeks of first report.) | ≥80 µg/100 g | ≥70µg/100 g | ≥60 µg/100 g | ≥60 µg/100 g | ≥60µg/100 g or average of last three blood samples or all blood samples over previous 6 months (whichever is over a longer time period) is 50 µg/100 g or greater unless last blood sample is 40 µg/100 g or less. |
| B. Frequency which employees exposed to action level of lead (30 µg/m 3 TWA) must have blood lead level checked (ZPP is also required in each occasion that a blood lead is obtained.): | |||||
| 1. Last blood lead level less than 40 µg/100 g | Every 6 months | Every 6 months | Every 6 months | Every 6 months | Every 6 months. |
| 2. Last blood lead level between 40 µg/100 g and level requiring medical removal (see A above) | Every 2 months | Every 2 months | Every 2 months | Every 2 months | Every 2 months. |
| 3. Employees removed from exposure to lead because of an elevated blood lead level | Every 1 month | Every 1 month | Every 1 month | Every 1 month | Every 1 month. |
| C. Permissible airborne exposure limit for workers removed from work due to an elevated blood lead level (without regard to respirator protection) | 100 µg/m 3 8 hr TWA | 50 µg/m 3 8 hr TWA | 30 µg/m 3 8 hr TWA | 30 µg/m 3 8 hr TWA | 30 µg/m 3 8 hr TWA. |
| D. Blood lead level confirmed with a second blood analysis, at which employee may return to work. Permissible exposure without regard to respirator protection is listed by industry in Table I | ·60 µg/100 g | ·50 µg/100 g | ·40 µg/100 g | ·40 µg/100 g | ·40 µg/100 g. |
| Note: When medical opinion indicates that an employee is at risk of material impairment from exposure to lead, the physician can remove an employee from exposures exceeding the action level (or less) or recommend special protective measures as deemed appropriate and necessary. Medical monitoring during the medical removal period can be more stringent than noted in the table above if the physician so specifies. Return to work or removal of limitations and special protections is permitted when the physician indicates that the worker is no longer at risk of material impairment. |
Under the standard's ultimate worker removal criteria, a worker is to be removed from any work having any eight hour TWA exposure to lead of 30 µg/m 3 or more whenever either of the following circumstances apply: (1) a blood lead level of 60 µg/100 g or greater is obtained and confirmed by a second follow-up blood lead level performed within two weeks after the employer receives the results of the first blood sampling test, or (2) the average of the previous three blood lead determinations or the average of all blood lead determinations conducted during the previous six months, whichever encompasses the longest time period, equals or exceeds 50 µg/100 g, unless the last blood sample indicates a blood lead level at or below 40 µg/100 g in which case the employee need not be removed. Medical removal is to continue until two consecutive blood lead levels are 40 µg/100 g or less.
During the first two years that the ultimate removal criteria are being phased in, the return criteria have been set to assure that a worker's blood lead level has substantially declined during the period of removal. From March 1, 1979 to March 1, 1980, the blood lead level requiring employee medical removal is 80 µg/100 g. Workers found to have a confirmed blood lead at this level or greater need only be removed from work having a daily 8 hour TWA exposure to lead at or above 100 µg/m 3. Workers so removed are to be returned to work when their blood lead levels are at or below 60 µg/100 g of whole blood. From March 1, 1980 to March 1, 1981, the blood lead level requiring medical removal is 70 µg/100 g. During this period workers need only be removed from jobs having a daily 8 hour TWA exposure to lead at or above 50 µg/m 3 and are to be returned to work when a level of 50 µg/100 g is achieved. Beginning March 1, 1981, return depends on a worker's blood lead level declining to 40 µg/100 g of whole blood.
As part of the standard, the employer is required to notify in writing each employee whose blood lead level exceeds 40 µg/100 g. In addition each such employee is to be informed that the standard requires medical removal with MRP benefits, discussed below, when an employee's blood lead level exceeds the above defined limits.
In addition to the above blood lead level criteria, temporary worker removal may also take place as a result of medical determinations and recommendations. Written medical opinions must be prepared after each examination pursuant to the standard. If the examining physician includes a medical finding, determination or opinion that the employee has a medical condition which places the employee at increased risk of material health impairment from exposure to lead, then the employee must be removed from exposure to lead at or above the action level. Alternatively, if the examining physician recommends special protective measures for an employee (e.g., use of a powered air purifying respirator) or recommends limitations on an employee's exposure to lead, then the employer must implement these recommendations. Recommendations may be more stringent than the specific provisions of the standard. The examining physician, therefore, is given broad flexibility to tailor special protective procedures to the needs of individual employees. This flexibility extends to the evaluation and management of pregnant workers and male and female workers who are planning to raise children. Based on the history, physical examination, and laboratory studies, the physician might recommend special protective measures or medical removal for an employee who is pregnant or who is planning to conceive a child when, in the physician's judgment, continued exposure to lead at the current job would pose a significant risk. The return of the employee to his or her former job status, or the removal of special protections or limitations, depends upon the examining physician determining that the employee is no longer at increased risk of material impairment or that special measures are no longer needed.
During the period of any form of special protection or removal, the employer must maintain the worker's earnings, seniority, and other employment rights and benefits (as though the worker had not been removed) for a period of up to 18 months. This economic protection will maximize meaningful worker participation in the medical surveillance program, and is appropriate as part of the employer's overall obligation to provide a safe and healthful workplace. The provisions of MRP benefits during the employee's removal period may, however, be conditioned upon participation in medical surveillance.
On rare occasions, an employee's blood lead level may not acceptably decline within 18 months of removal. This situation will arise only in unusual circumstances, thus the standard relies on an individual medical examination to determine how to protect such an employee. This medical determination is to be based on both laboratory values, including lead levels, zinc protoporphyrin levels, blood counts, and other tests felt to be warranted, as well as the physician's judgment that any symptoms or findings on physical examination are a result of lead toxicity. The medical determination may be that the employee is incapable of ever safely returning to his or her former job status. The medical determination may provide additional removal time past 18 months for some employees or specify special protective measures to be implemented.
The lead standard provides for a multiple physician review in cases where the employee wishes a second opinion concerning potential lead poisoning or toxicity. If an employee wishes a second opinion, he or she can make an appointment with a physician of his or her choice. This second physician will review the findings, recommendations or determinations of the first physician and conduct any examinations, consultations or tests deemed necessary in an attempt to make a final medical determination. If the first and second physicians do not agree in their assessment they must try to resolve their differences. If they cannot reach an agreement then they must designate a third physician to resolve the dispute.
The employer must provide examining and consulting physicians with the following specific information: a copy of the lead regulations and all appendices, a description of the employee's duties as related to exposure, the exposure level to lead and any other toxic substances (if applicable), a description of personal protective equipment used, blood lead levels, and all prior written medical opinions regarding the employee in the employer's possession or control. The employer must also obtain from the physician and provide the employee with a written medical opinion containing blood lead levels, the physicians's opinion as to whether the employee is at risk of material impairment to health, any recommended protective measures for the employee if further exposure is permitted, as well as any recommended limitations upon an employee's use of respirators.
Employers must instruct each physician not to reveal to the employer in writing or in any other way his or her findings, laboratory results, or diagnoses which are felt to be unrelated to occupational lead exposure. They must also instruct each physician to advise the employee of any occupationally or non-occupationally related medical condition requiring further treatment or evaluation.
The standard provides for the use of respirators where engineering and other primary controls have not been fully implemented. However, the use of respirator protection shall not be used in lieu of temporary medical removal due to elevated blood lead levels or findings that an employee is at risk of material health impairment. This is based on the numerous inadequacies of respirators including skin rash where the facepiece makes contact with the skin, unacceptable stress to breathing in some workers with underlying cardiopulmonary impairment, difficulty in providing adequate fit, the tendency for respirators to create additional hazards by interfering with vision, hearing, and mobility, and the difficulties of assuring the maximum effectiveness of a complicated work practice program involving respirators. Respirators do, however, serve a useful function where engineering and work practice controls are inadequate by providing supplementary, interim, or short-term protection, provided they are properly selected for the environment in which the employee will be working, properly fitted to the employee, maintained and cleaned periodically, and worn by the employee when required.
In its final standard on occupational exposure to inorganic lead, OSHA has prohibited prophylactic chelation. Diagnostic and therapeutic chelation are permitted only under the supervision of a licensed physician with appropriate medical monitoring in an acceptable clinical setting. The decision to initiate chelation therapy must be made on an individual basis and take into account the severity of symptoms felt to be a result of lead toxicity along with blood lead levels, ZPP levels, and other laboratory tests as appropriate. EDTA and penicillamine which are the primary chelating agents used in the therapy of occupational lead poisoning have significant potential side effects and their use must be justified on the basis of expected benefits to the worker. Unless frank and severe symptoms are present, therapeutic chelation is not recommended given the opportunity to remove a worker from exposure and allow the body to naturally excrete accumulated lead. As a diagnostic aid, the chelation mobilization test using CA-EDTA has limited applicability. According to some investigators, the test can differentiate between lead-induced and other nephropathies. The test may also provide an estimation of the mobile fraction of the total body lead burden.
Employers are required to assure that accurate records are maintained on exposure monitoring, medical surveillance, and medical removal for each employee. Exposure monitoring and medical surveillance records must be kept for 40 years or the duration of employment plus 20 years, whichever is longer, while medical removal records must be maintained for the duration of employment. All records required under the standard must be made available upon request to the Assistant Secretary of Labor for Occupational Safety and Health and the Director of the National Institute for Occupational Safety and Health. Employers must also make environmental and biological monitoring and medical removal records available to affected employees and to former employees or their authorized employee representatives. Employees or their specifically designated representatives have access to their entire medical surveillance records.
In addition, the standard requires that the employer inform all workers exposed to lead at or above the action level of the provisions of the standard and all its appendices, the purpose and description of medical surveillance and provisions for medical removal protection if temporary removal is required. An understanding of the potential health effects of lead exposure by all exposed employees along with full understanding of their rights under the lead standard is essential for an effective monitoring program.
ii. adverse health effects of inorganic lead
Although the toxicity of lead has been known for 2,000 years, the knowledge of the complex relationship between lead exposure and human response is still being refined. Significant research into the toxic properties of lead continues throughout the world, and it should be anticipated that our understanding of thresholds of effects and margins of safety will be improved in future years. The provisions of the lead standard are founded on two prime medical judgments: first, the prevention of adverse health effects from exposure to lead throughout a working lifetime requires that worker blood lead levels be maintained at or below 40 µg/100 g and second, the blood lead levels of workers, male or female, who intend to parent in the near future should be maintained below 30 µg/100 g to minimize adverse reproductive health effects to the parents and developing fetus. The adverse effects of lead on reproduction are being actively researched and OSHA encourages the physician to remain abreast of recent developments in the area to best advise pregnant workers or workers planning to conceive children.
The spectrum of health effects caused by lead exposure can be subdivided into five developmental stages: normal, physiological changes of uncertain significance, pathophysiological changes, overt symptoms (morbidity), and mortality. Within this process there are no sharp distinctions, but rather a continuum of effects. Boundaries between categories overlap due to the wide variation of individual responses and exposures in the working population. OSHA's development of the lead standard focused on pathophysiological changes as well as later stages of disease.
1. Heme Synthesis Inhibition. The earliest demonstrated effect of lead involves its ability to inhibit at least two enzymes of the heme synthesis pathway at very low blood levels. Inhibition of delta aminolevulinic acid dehydrase (ALA-D) which catalyzes the conversion of delta-aminolevulinic acid (ALA) to protoporphyrin is observed at a blood lead level below 20 µg/100 g whole blood. At a blood lead level of 40 ug/100 g, more than 20% of the population would have 70% inhibition of ALA-D. There is an exponential increase in ALA excretion at blood lead levels greater than 40 µg/100 g.
Another enzyme, ferrochelatase, is also inhibited at low blood lead levels. Inhibition of ferrochelatase leads to increased free erythrocyte protoporphyrin (FEP) in the blood which can then bind to zinc to yield zinc protoporphyrin. At a blood lead level of 50 µg/100 g or greater, nearly 100% of the population will have an increase in FEP. There is also an exponential relationship between blood lead levels greater than 40 µg/100 g and the associated ZPP level, which has led to the development of the ZPP screening test for lead exposure.
While the significance of these effects is subject to debate, it is OSHA's position that these enzyme disturbances are early stages of a disease process which may eventually result in the clinical symptoms of lead poisoning. Whether or not the effects do progress to the later stages of clinical disease, disruption of these enzyme processes over a working lifetime is considered to be a material impairment of health.
One of the eventual results of lead-induced inhibition of enzymes in the heme synthesis pathway is anemia which can be asymptomatic if mild but associated with a wide array of symptoms including dizziness, fatigue, and tachycardia when more severe. Studies have indicated that lead levels as low as 50 µg/100 g can be associated with a definite decreased hemoglobin, although most cases of lead-induced anemia, as well as shortened red-cell survival times, occur at lead levels exceeding 80 µg/100 g. Inhibited hemoglobin synthesis is more common in chronic cases whereas shortened erythrocyte life span is more common in acute cases.
In lead-induced anemias, there is usually a reticulocytosis along with the presence of basophilic stippling, and ringed sideroblasts, although none of the above are pathognomonic for lead-induced anemia.
2. Neurological Effects. Inorganic lead has been found to have toxic effects on both the central and peripheral nervous systems. The earliest stages of lead-induced central nervous system effects first manifest themselves in the form of behavioral disturbances and central nervous system symptoms including irritability, restlessness, insomnia and other sleep disturbances, fatigue, vertigo, headache, poor memory, tremor, depression, and apathy. With more severe exposure, symptoms can progress to drowsiness, stupor, hallucinations, delerium, convulsions and coma.
The most severe and acute form of lead poisoning which usually follows ingestion or inhalation of large amounts of lead is acute encephalopathy which may arise precipitously with the onset of intractable seizures, coma, cardiorespiratory arrest, and death within 48 hours.
While there is disagreement about what exposure levels are needed to produce the earliest symptoms, most experts agree that symptoms definitely can occur at blood lead levels of 60 µg/100 g whole blood and therefore recommend a 40 µg/100 g maximum. The central nervous system effects frequently are not reversible following discontinued exposure or chelation therapy and when improvement does occur, it is almost always only partial.
The peripheral neuropathy resulting from lead exposure characteristically involves only motor function with minimal sensory damage and has a marked predilection for the extensor muscles of the most active extremity. The peripheral neuropathy can occur with varying degrees of severity. The earliest and mildest form which can be detected in workers with blood lead levels as low as 50 µg/100 g is manifested by slowing of motor nerve conduction velocity often without clinical symptoms. With progression of the neuropathy there is development of painless extensor muscle weakness usually involving the extensor muscles of the fingers and hand in the most active upper extremity, followed in severe cases by wrist drop or, much less commonly, foot drop.
In addition to slowing of nerve conduction, electromyographical studies in patients with blood lead levels greater than 50 µg/100 g have demonstrated a decrease in the number of acting motor unit potentials, an increase in the duration of motor unit potentials, and spontaneous pathological activity including fibrillations and fasciculations. Whether these effects occur at levels of 40 µg/100 g is undetermined.
While the peripheral neuropathies can occasionally be reversed with therapy, again such recovery is not assured particularly in the more severe neuropathies and often improvement is only partial. The lack of reversibility is felt to be due in part to segmental demyelination.
3. Gastrointestinal. Lead may also affect the gastrointestinal system producing abdominal colic or diffuse abdominal pain, constipation, obstipation, diarrhea, anorexia, nausea and vomiting. Lead colic rarely develops at blood lead levels below 80 µg/100 g.
4. Renal. Renal toxicity represents one of the most serious health effects of lead poisoning. In the early stages of disease nuclear inclusion bodies can frequently be identified in proximal renal tubular cells. Renal function remains normal and the changes in this stage are probably reversible. With more advanced disease there is progressive interstitial fibrosis and impaired renal function. Eventually extensive interstitial fibrosis ensues with sclerotic glomeruli and dilated and atrophied proximal tubules; all represent end stage kidney disease. Azotemia can be progressive, eventually resulting in frank uremia necessitating dialysis. There is occasionally associated hypertension and hyperuricemia with or without gout.
Early kidney disease is difficult to detect. The urinalysis is normal in early lead nephropathy and the blood urea nitrogen and serum creatinine increase only when two-thirds of kidney function is lost. Measurement of creatinine clearance can often detect earlier disease as can other methods of measurement of glomerular filtration rate. An abnormal Ca-EDTA mobilization test has been used to differentiate between lead-induced and other nephropathies, but this procedure is not widely accepted. A form of Fanconi syndrome with aminoaciduria, glycosuria, and hyperphosphaturia indicating severe injury to the proximal renal tubules is occasionally seen in children.
5. Reproductive effects. Exposure to lead can have serious effects on reproductive function in both males and females. In male workers exposed to lead there can be a decrease in sexual drive, impotence, decreased ability to produce healthy sperm, and sterility. Malformed sperm (teratospermia), decreased number of sperm (hypospermia), and sperm with decreased motility (asthenospermia) can all occur. Teratospermia has been noted at mean blood lead levels of 53 µg/100 g and hypospermia and asthenospermia at 41 µg/100 g. Furthermore, there appears to be a dose-response relationship for teratospermia in lead exposed workers.
Women exposed to lead may experience menstrual disturbances including dysmenorrhea, menorrhagia and amenorrhea. Following exposure to lead, women have a higher frequency of sterility, premature births, spontaneous miscarriages, and stillbirths.
Germ cells can be affected by lead and cause genetic damage in the egg or sperm cells before conception and result in failure to implant, miscarriage, stillbirth, or birth defects.
Infants of mothers with lead poisoning have a higher mortality during the first year and suffer from lowered birth weights, slower growth, and nervous system disorders.
Lead can pass through the placental barrier and lead levels in the mother's blood are comparable to concentrations of lead in the umbilical cord at birth. Transplacental passage becomes detectable at 12-14 weeks of gestation and increases until birth.
There is little direct data on damage to the fetus from exposure to lead but it is generally assumed that the fetus and newborn would be at least as susceptible to neurological damage as young children. Blood lead levels of 50-60 µg/100 g in children can cause significant neurobehavioral impairments and there is evidence of hyperactivity at blood levels as low as 25 µg/100 g. Given the overall body of literature concerning the adverse health effects of lead in children, OSHA feels that the blood lead level in children should be maintained below 30 µg/100 g with a population mean of 15 µg/100 g. Blood lead levels in the fetus and newborn likewise should not exceed 30 µg/100 g.
Because of lead's ability to pass through the placental barrier and also because of the demonstrated adverse effects of lead on reproductive function in both the male and female as well as the risk of genetic damage of lead on both the ovum and sperm, OSHA recommends a 30 µg/100 g maximum permissible blood lead level in both males and females who wish to bear children.
6. Other toxic effects. Debate and research continue on the effects of lead on the human body. Hypertension has frequently been noted in occupationally exposed individuals although it is difficult to assess whether this is due to lead's adverse effects on the kidney or if some other mechanism is involved. Vascular and electrocardiogarphic changes have been detected but have not been well characterized. Lead is thought to impair thyroid function and interfere with the pituitary-adrenal axis, but again these effects have not been well defined.
iii. medical evaluation
The most important principle in evaluating a worker for any occupational disease including lead poisoning is a high index of suspicion on the part of the examining physician. As discussed in Section 2, lead can affect numerous organ systems and produce a wide array of signs and symptoms, most of which are non-specific and subtle in nature at least in the early stages of disease. Unless serious concern for lead toxicity is present, many of the early clues to diagnosis may easily be overlooked.
The crucial initial step in the medical evaluation is recognizing that a worker's employment can result in exposure to lead. The worker will frequently be able to define exposures to lead and lead containing materials but often will not volunteer this information unless specifically asked. In other situations the worker may not know of any exposures to lead but the suspicion might be raised on the part of the physician because of the industry or occupation of the worker. Potential occupational exposure to lead and its compounds occur in at least 120 occupations, including lead smelting, the manufacture of lead storage batteries, the manufacture of lead pigments and products containing pigments, solder manufacture, shipbuilding and ship repair, auto manufacturing, construction, and painting.
Once the possibility for lead exposure is raised, the focus can then be directed toward eliciting information from the medical history, physical exam, and finally from laboratory data to evaluate the worker for potential lead toxicity.
A complete and detailed work history is important in the initial evaluation. A listing of all previous employment with information on work processes, exposure to fumes or dust, known exposures to lead or other toxic substances, respiratory protection used, and previous medical surveillance should all be included in the worker's record. Where exposure to lead is suspected, information concerning on-the-job personal hygiene, smoking or eating habits in work areas, laundry procedures, and use of any protective clothing or respiratory protection equipment should be noted. A complete work history is essential in the medical evaluation of a worker with suspected lead toxicity, especially when long term effects such as neurotoxicity and nephrotoxicity are considered.
The medical history is also of fundamental importance and should include a listing of all past and current medical conditions, current medications including proprietary drug intake, previous surgeries and hospitalizations, allergies, smoking history, alcohol consumption, and also non-occupational lead exposures such as hobbies (hunting, riflery). Also known childhood exposures should be elicited. Any previous history of hematological, neurological, gastrointestinal, renal, psychological, gynecological, genetic, or reproductive problems should be specifically noted.
A careful and complete review must be performed to assess both recognized complaints and subtle or slowly acquired symptoms which the worker might not appreciate as being significant. The review of symptoms should include the following:
General—weight loss, fatigue, decreased appetite.
Head, Eyes, Ears, Nose, Throat (HEENT)—headaches, visual disturbances or decreased visual acuity, hearing deficits or tinnitus, pigmentation of the oral mucosa, or metallic taste in mouth.
Cardio-pulmonary—shortness of breath, cough, chest pains, palpitations, or orthopnea.
Gastrointestinal—nausea, vomiting, heartburn, abdominal pain, constipation or diarrhea.
Neurologic—irritability, insomnia, weakness (fatigue), dizziness, loss of memory, confusion, hallucinations, incoordination, ataxia, decreased strength in hands or feet, disturbances in gait, difficulty in climbing stairs, or seizures.
Hematologic—pallor, easy fatigability, abnormal blood loss, melena.
Reproductive (male and female and spouse where relevant)—history of infertility, impotence, loss of libido, abnormal menstrual periods, history of miscarriages, stillbirths, or children with birth defects.
Musculo-skeletal—muscle and joint pains.
The physical examination should emphasize the neurological, gastrointestinal, and cardiovascular systems. The worker's weight and blood pressure should be recorded and the oral mucosa checked for pigmentation characteristic of a possible Burtonian or lead line on the gingiva. It should be noted, however, that the lead line may not be present even in severe lead poisoning if good oral hygiene is practiced.
The presence of pallor on skin examination may indicate an anemia, which if severe might also be associated with a tachycardia. If an anemia is suspected, an active search for blood loss should be undertaken including potential blood loss through the gastrointestinal tract.
A complete neurological examination should include an adequate mental status evaluation including a search for behavioral and psychological disturbances, memory testing, evaluation for irritability, insomnia, hallucinations, and mental clouding. Gait and coordination should be examined along with close observation for tremor. A detailed evaluation of peripheral nerve function including careful sensory and motor function testing is warranted. Strength testing particularly of extensor muscle groups of all extremities is of fundamental importance.
Cranial nerve evaluation should also be included in the routine examination.
The abdominal examination should include auscultation for bowel sounds and abdominal bruits and palpation for organomegaly, masses, and diffuse abdominal tenderness.
Cardiovascular examination should evaluate possible early signs of congestive heart failure. Pulmonary status should be addressed particularly if respirator protection is contemplated.
As part of the medical evaluation, the lead standard requires the following laboratory studies:
1. Blood lead level
2. Hemoglobin and hematocrit determinations, red cell indices, and examination of the peripheral blood smear to evaluate red blood cell morphology
3. Blood urea nitrogen
4. Serum creatinine
5. Routine urinalysis with microscopic examination.
6. A zinc protoporphyrin level
In addition to the above, the physician is authorized to order any further laboratory or other tests which he or she deems necessary in accordance with sound medical practice. The evaluation must also include pregnancy testing or laboratory evaluation of male fertility if requested by the employee.
Additional tests which are probably not warranted on a routine basis but may be appropriate when blood lead and ZPP levels are equivocal include delta aminolevulinic acid and coproporphyrin concentrations in the urine, and dark-field illumination for detection of basophilic stippling in red blood cells.
If an anemia is detected further studies including a careful examination of the peripheral smear, reticulocyte count, stool for occult blood, serum iron, total iron binding capacity, bilirubin, and, if appropriate, vitamin B12 and folate may be of value in attempting to identify the cause of the anemia.
If a peripheral neuropathy is suspected, nerve conduction studies are warranted both for diagnosis and as a basis to monitor any therapy.
If renal disease is questioned, a 24 hour urine collection for creatinine clearance, protein, and electrolytes may be indicated. Elevated uric acid levels may result from lead-induced renal disease and a serum uric acid level might be performed.
An electrocardiogram and chest x-ray may be obtained as deemed appropriate.
Sophisticated and highly specialized testing should not be done routinely and where indicated should be under the direction of a specialist.
iv. laboratory evaluation
The blood lead level at present remains the single most important test to monitor lead exposure and is the test used in the medical surveillance program under the lead standard to guide employee medical removal. The ZPP has several advantages over the blood lead level. Because of its relatively recent development and the lack of extensive data concerning its interpretation, the ZPP currently remains an ancillary test.
This section will discuss the blood lead level and ZPP in detail and will outline their relative advantages and disadvantages. Other blood tests currently available to evaluate lead exposure will also be reviewed.
The blood lead level is a good index of current or recent lead absorption when there is no anemia present and when the worker has not taken any chelating agents. However, blood lead levels along with urinary lead levels do not necessarily indicate the total body burden of lead and are not adequate measures of past exposure. One reason for this is that lead has a high affinity for bone and up to 90% of the body's total lead is deposited there. A very important component of the total lead body burden is lead in soft tissue (liver, kidney, and brain). This fraction of the lead body burden, the biologically active lead, is not entirely reflected by blood lead levels since it is a function of the dynamics of lead absorption, distribution, deposition in bone and excretion. Following discontinuation of exposure to lead, the excess body burden is only slowly mobilized from bone and other relatively stable body stores and excreted. Consequently, a high blood lead level may only represent recent heavy exposure to lead without a significant total body excess and likewise a low blood lead level does not exclude an elevated total body burden of lead.
Also due to its correlation with recent exposures, the blood lead level may vary considerably over short time intervals.
To minimize laboratory error and erroneous results due to contamination, blood specimens must be carefully collected after thorough cleaning of the skin with appropriate methods using lead-free blood containers and analyzed by a reliable laboratory. Under the standard, samples must be analyzed in laboratories which are approved by the Center for Disease Control (CDC) or which have received satisfactory grades in proficiency testing by the CDC in the previous year. Analysis is to be made using atomic absorption spectrophotometry, anodic stripping voltammetry or any method which meets the accuracy requirements set forth by the standard.
The determination of lead in urine is generally considered a less reliable monitoring technique than analysis of whole blood primarily due to individual variability in urinary excretion capacity as well as the technical difficulty of obtaining accurate 24 hour urine collections. In addition, workers with renal insufficiency, whether due to lead or some other cause, may have decreased lead clearance and consequently urine lead levels may underestimate the true lead burden. Therefore, urine lead levels should not be used as a routine test.
The zinc protoporphyrin test, unlike the blood lead determination, measures an adverse metabolic effect of lead and as such is a better indicator of lead toxicity than the level of blood lead itself. The level of ZPP reflects lead absorption over the preceding 3 to 4 months, and therefore is a better indicator of lead body burden. The ZPP requires more time than the blood lead to read significantly elevated levels; the return to normal after discontinuing lead exposure is also slower. Furthermore, the ZPP test is simpler, faster, and less expensive to perform and no contamination is possible. Many investigators believe it is the most reliable means of monitoring chronic lead absorption.
Zinc protoporphyrin results from the inhibition of the enzyme ferrochelatase which catalyzes the insertion of an iron molecule into the protoporphyrin molecule, which then becomes heme. If iron is not inserted into the molecule then zinc, having a greater affinity for protoporphyrin, takes the place of the iron, forming ZPP.
An elevation in the level of circulating ZPP may occur at blood lead levels as low as 20-30 µg/100 g in some workers. Once the blood lead level has reached 40 µg/100 g there is more marked rise in the ZPP value from its normal range of less than 100 µg/100 ml. Increases in blood lead levels beyond 40 µg/100 g are associated with exponential increases in ZPP.
Whereas blood lead levels fluctuate over short time spans, ZPP levels remain relatively stable. ZPP is measured directly in red blood cells and is present for the cell's entire 120 day life-span. Therefore, the ZPP level in blood reflects the average ZPP production over the previous 3-4 months and consequently the average lead exposure during that time interval.
It is recommended that a hematocrit be determined whenever a confirmed ZPP of 50 µg/100 ml whole blood is obtained to rule out a significant underlying anemia. If the ZPP is in excess of 100 µg/100 ml and not associated with abnormal elevations in blood lead levels, the laboratory should be checked to be sure that blood leads were determined using atomic absorption spectrophotometry anodic stripping voltammetry, or any method which meets the accuracy requirements set forth by the standard by a CDC approved laboratory which is experienced in lead level determinations. Repeat periodic blood lead studies should be obtained in all individuals with elevated ZPP levels to be certain that an associated elevated blood lead level has not been missed due to transient fluctuations in blood leads.
ZPP has a characteristic fluorescence spectrum with a peak at 594 nm which is detectable with a hematofluorimeter. The hematofluorimeter is accurate and portable and can provide on-site, instantaneous results for workers who can be frequently tested via a finger prick.
However, careful attention must be given to calibration and quality control procedures. Limited data on blood lead—ZPP correlations and the ZPP levels which are associated with the adverse health effects discussed in Section 2 are the major limitations of the test. Also it is difficult to correlate ZPP levels with environmental exposure and there is some variation of response with age and sex. Nevertheless, the ZPP promises to be an important diagnostic test for the early detection of lead toxicity and its value will increase as more data is collected regarding its relationship to other manifestations of lead poisoning.
Levels of delta-aminolevulinic acid (ALA) in the urine are also used as a measure of lead exposure. Increasing concentrations of ALA are believed to result from the inhibition of the enzyme delta-aminolevulinic acid dehydrase (ALA-D). Although the test is relatively easy to perform, inexpensive, and rapid, the disadvantages include variability in results, the necessity to collect a complete 24 hour urine sample which has a specific gravity greater than 1.010, and also the fact that ALA decomposes in the presence of light.
The pattern of porphyrin excretion in the urine can also be helpful in identifying lead intoxication. With lead poisoning, the urine concentrations of coproporphyrins I and II, porphobilinogen and uroporphyrin I rise. The most important increase, however, is that of coproporphyrin III; levels may exceed 5,000 µg/1 in the urine in lead poisoned individuals, but its correlation with blood lead levels and ZPP are not as good as those of ALA. Increases in urinary porphyrins are not diagnostic of lead toxicity and may be seen in porphyria, some liver diseases, and in patients with high reticulocyte counts.
Summary. The Occupational Safety and Health Administration's standard for inorganic lead places significant emphasis on the medical surveillance of all workers exposed to levels of inorganic lead above the action level of 30 µg/m 3 TWA. The physician has a fundamental role in this surveillance program, and in the operation of the medical removal protection program.
Even with adequate worker education on the adverse health effects of lead and appropriate training in work practices, personal hygiene and other control measures, the physician has a primary responsibility for evaluating potential lead toxicity in the worker. It is only through a careful and detailed medical and work history, a complete physical examination and appropriate laboratory testing that an accurate assessment can be made. Many of the adverse health effects of lead toxicity are either irreversible or only partially reversible and therefore early detection of disease is very important.
This document outlines the medical monitoring program as defined by the occupational safety and health standard for inorganic lead. It reviews the adverse health effects of lead poisoning and describes the important elements of the history and physical examinations as they relate to these adverse effects. Finally, the appropriate laboratory testing for evaluating lead exposure and toxicity is presented.
It is hoped that this review and discussion will give the physician a better understanding of the OSHA standard with the ultimate goal of protecting the health and well-being of the worker exposed to lead under his or her care.
[43 FR 53007, Nov. 14, 1978]
Editorial Note:
Federal Register
www.govinfo.gov.
For the purposes of this section the following definitions apply:
Action level means a concentration of airborne chromium (VI) of 2.5 micrograms per cubic meter of air (2.5 µgm/m 3 ) calculated as an 8-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Chromium (VI) [hexavalent chromium or Cr(VI)] means chromium with a valence of positive six, in any form and in any compound.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence that results, or is likely to result, in an uncontrolled release of chromium (VI). If an incidental release of chromium (VI) can be controlled at the time of release by employees in the immediate release area, or by maintenance personnel, it is not an emergency.
Employee exposure means the exposure to airborne chromium (VI) that would occur if the employee were not using a respirator.
High-efficiency particulate air [HEPA] filter means a filter that is at least 99.97 percent efficient in removing mono-dispersed particles of 0.3 micrometers in diameter or larger.
Historical monitoring data means data from chromium (VI) monitoring conducted prior to May 30, 2006, obtained during work operations conducted under workplace conditions closely resembling the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Objective data means information such as air monitoring data from industry-wide surveys or calculations based on the composition or chemical and physical properties of a substance demonstrating the employee exposure to chromium (VI) associated with a particular product or material or a specific process, operation, or activity. The data must reflect workplace conditions closely resembling the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Physician or other licensed health care professional [PLHCP] is an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required by paragraph (k) of this section.
Regulated area means an area, demarcated by the employer, where an employee's exposure to airborne concentrations of chromium (VI) exceeds, or can reasonably be expected to exceed, the PEL.
This section means this § 1910.1026 chromium (VI) standard.
The employer shall ensure that no employee is exposed to an airborne concentration of chromium (VI) in excess of 5 micrograms per cubic meter of air (5 µgm/m 3 ), calculated as an 8-hour time-weighted average (TWA).
Each employer who has a workplace or work operation covered by this section shall determine the 8-hour TWA exposure for each employee exposed to chromium (VI). This determination shall be made in accordance with either paragraph (d)(2) or paragraph (d)(3) of this section.
The employer shall determine the 8-hour TWA exposure for each employee on the basis of any combination of air monitoring data, historical monitoring data, or objective data sufficient to accurately characterize employee exposure to chromium (VI).
Where air monitoring is performed to comply with the requirements of this section, the employer shall use a method of monitoring and analysis that can measure chromium (VI) to within an accuracy of plus or minus 25 percent (±25%) and can produce accurate measurements to within a statistical confidence level of 95 percent for airborne concentrations at or above the action level.
The employer shall establish a regulated area wherever an employee's exposure to airborne concentrations of chromium (VI) is, or can reasonably be expected to be, in excess of the PEL.
The employer shall ensure that regulated areas are demarcated from the rest of the workplace in a manner that adequately establishes and alerts employees of the boundaries of the regulated area.
The employer shall limit access to regulated areas to:
The employer shall not rotate employees to different jobs to achieve compliance with the PEL.
Where respiratory protection is required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respiratory protection is required during:
Where respirator use is required by this section, the employer shall institute a respiratory protection program in accordance with § 1910.134, which covers each employee required to use a respirator.
Where a hazard is present or is likely to be present from skin or eye contact with chromium (VI), the employer shall provide appropriate personal protective clothing and equipment at no cost to employees, and shall ensure that employees use such clothing and equipment.
Where protective clothing and equipment is required, the employer shall provide change rooms in conformance with 29 CFR 1910.141. Where skin contact with chromium (VI) occurs, the employer shall provide washing facilities in conformance with 29 CFR 1910.141. Eating and drinking areas provided by the employer shall also be in conformance with § 1910.141.
The employer shall assure that change rooms are equipped with separate storage facilities for protective clothing and equipment and for street clothes, and that these facilities prevent cross-contamination.
The employer shall ensure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in regulated areas, or in areas where skin or eye contact with chromium (VI) occurs; or carry the products associated with these activities, or store such products in these areas.
The employer shall ensure that:
The employer shall ensure that:
The employer shall provide a medical examination:
A medical examination consists of:
The employer shall ensure that the examining PLHCP has a copy of this standard, and shall provide the following information:
This standard applies to all occupational exposures to cadmium and cadmium compounds, in all forms, and in all industries covered by the Occupational Safety and Health Act, except the construction-related industries, which are covered under 29 CFR 1926.63.
Action level (AL) is defined as an airborne concentration of cadmium of 2.5 micrograms per cubic meter of air (2.5 µg/m 3 ), calculated as an 8-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person authorized by the employer and required by work duties to be present in regulated areas or any person authorized by the OSH Act or regulations issued under it to be in regulated areas.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Employee exposure and similar language referring to the air cadmium level to which an employee is exposed means the exposure to airborne cadmium that would occur if the employee were not using respiratory protective equipment.
Final medical determination is the written medical opinion of the employee's health status by the examining physician under paragraphs (l)(3)-
High-efficiency particulate air (HEPA) filter means a filter capable of trapping and retaining at least 99.97 percent of mono-dispersed particles of 0.3 micrometers in diameter.
Regulated area means an area demarcated by the employer where an employee's exposure to airborne concentrations of cadmium exceeds, or can reasonably be expected to exceed the permissible exposure limit (PEL).
This section means this cadmium standard.
The employer shall assure that no employee is exposed to an airborne concentration of cadmium in excess of five micrograms per cubic meter of air (5 µg/m 3 ), calculated as an eight-hour time-weighted average exposure (TWA).
Except as provided for in paragraphs (d)(2)(ii) and (d)(2)(iii) of this section, the employer shall monitor employee exposures and shall base initial determinations on the monitoring results.
The employer also shall institute the exposure monitoring required under paragraphs (d)(2)(i) and (d)(3) of this section whenever there has been a change in the raw materials, equipment, personnel, work practices, or finished products that may result in additional employees being exposed to cadmium at or above the action level or in employees already exposed to cadmium at or above the action level being exposed above the PEL, or whenever the employer has any reason to suspect that any other change might result in such further exposure.
The employer shall use a method of monitoring and analysis that has an accuracy of not less than plus or minus 25 percent (±25%), with a confidence level of 95 percent, for airborne concentrations of cadmium at or above the action level, the permissible exposure limit (PEL), and the separate engineering control air limit (SECAL).
The employer shall establish a regulated area wherever an employee's exposure to airborne concentrations of cadmium is, or can reasonably be expected to be in excess of the permissible exposure limit (PEL).
Regulated areas shall be demarcated from the rest of the workplace in any manner that adequately establishes and alerts employees of the boundaries of the regulated area.
Access to regulated areas shall be limited to authorized persons.
Each person entering a regulated area shall be supplied with and required to use a respirator, selected in accordance with paragraph (g)(2) of this section.
The employer shall assure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in regulated areas, carry the products associated with these activities into regulated areas, or store such products in those areas.
| Industry | Process | SECAL (µg/m 3 ) |
|---|---|---|
| Nickel cadmium battery | Plate making, plate preparation | 50 |
| All other processes | 15 | |
| Zinc/Cadmium refining* | Cadmium refining, casting, melting, oxide production, sinter plant | 50 |
| Pigment manufacture | Calcine, crushing, milling, blending | 50 |
| All other processes | 15 | |
| Stabilizers* | Cadmium oxide charging, crushing, drying, blending | 50 |
| Lead smelting* | Sinter plant, blast furnace, baghouse, yard area | 50 |
| Plating* | Mechanical plating | 15 |
| *Processes in these industries that are not specified in this table must achieve the PEL using engineering controls and work practices as required in f(1)(i). |
If air from exhaust ventilation is recirculated into the workplace, the system shall have a high efficiency filter and be monitored to assure effectiveness.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer shall develop and implement a written plan for dealing with emergency situations involving substantial releases of airborne cadmium. The plan shall include provisions for the use of appropriate respirators and personal protective equipment. In addition, employees not essential to correcting the emergency situation shall be restricted from the area and normal operations halted in that area until the emergency is abated.
If an employee is exposed to airborne cadmium above the PEL or where skin or eye irritation is associated with cadmium exposure at any level, the employer shall provide at no cost to the employee, and assure that the employee uses, appropriate protective work clothing and equipment that prevents contamination of the employee and the employee's garments. Protective work clothing and equipment includes, but is not limited to:
For employees whose airborne exposure to cadmium is above the PEL, the employer shall provide clean change rooms, handwashing facilities, showers, and lunchroom facilities that comply with 29 CFR 1910.141.
The employer shall assure that change rooms are equipped with separate storage facilities for street clothes and for protective clothing and equipment, which are designed to prevent dispersion of cadmium and contamination of the employee's street clothes.
An initial examination is not required to be provided if adequate records show that the employee has been examined in accordance with the requirements of paragraph (l)(2)(ii) of this section within the past 12 months. In that case, such records shall be maintained as part of the employee's medical record and the prior exam shall be treated as if it were an initial examination for the purposes of paragraphs (l)(3) and (4) of this section.
Within 90 days after receipt of biological monitoring results, the employer shall provide a full medical examination to the employee in accordance with the requirements of paragraph (l)(4)(ii) of this section. After completing the medical examination, the examining physician shall determine in a written medical opinion whether to medically remove the employee. However, if the initial biological monitoring results and the biological monitoring results obtained during the medical examination both show that: CdU exceeds 15 µg/g Cr; or CdB exceeds 15 µg/lwb; or β 2 -M exceeds 1500 µg/g Cr, and in addition CdU exceeds 3 µg/g Cr or CdB exceeds 5 µg/liter of whole blood, then the physician shall medically remove the employee from exposure to cadmium at or above the action level. If the second set of biological monitoring results obtained during the medical examination does not show that a mandatory removal trigger level has been exceeded, then the employee is not required to be removed by the mandatory provisions of this paragraph. If the employee is not required to be removed by the mandatory provisions of this paragraph or by the physician's determination, then until the employee's CdU level falls to or below 3 µg/g Cr, β 2 -M level falls to or below 300 µg/g Cr and CdB level falls to or below 5 µg/lwb, the employer shall:
Blood pressure, the respiratory system, and the urinary system;
inch by 17 inch or other reasonably-sized standard film or digital posterior-anterior chest X-ray (after the initial X-ray, the frequency of chest X-rays is to be determined by the examining physician);
The employee's work practices and personal hygiene; the employee's respirator use, if any; the employee's smoking history and status; the respiratory protection program; the hygiene facilities; and the maintenance and effectiveness of the relevant engineering controls;
This examination shall be provided prior to the employee's being assigned to a job that requires the use of a respirator or no later than 90 days after this section goes into effect, whichever date is later, to any employee without a medical examination within the preceding 12 months that satisfies the requirements of this paragraph.
The employer shall provide the following information to the examining physician:
The employer and an employee or designated employee representative may agree upon the use of any alternate form of physician determination in lieu of the multiple physician review provided by paragraph (l)(13) of this section, so long as the alternative is expeditious and at least as protective of the employee.
In addition to other medical events that are required to be reported on the OSHA Form No. 200, the employer shall report any abnormal condition or disorder caused by occupational exposure to cadmium associated with employment as specified in Chapter (V)(E) of the Reporting Guidelines for Occupational Injuries and Illnesses.
DANGER
CADMIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS AND KIDNEYS
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
CADMIUM
CANCER HAZARD
CAN CAUSE LUNG AND KIDNEY DISEASE
AUTHORIZED PERSONNEL ONLY
RESPIRATORS REQUIRED IN THIS AREA
DANGER
CONTAINS CADMIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS AND KIDNEYS
AVOID CREATING DUST
DANGER
CONTAINS CADMIUM
CANCER HAZARD
AVOID CREATING DUST
CAN CAUSE LUNG AND KIDNEY DISEASE
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to cadmium.
When observation of monitoring requires entry into an area where the use of protective clothing or equipment is required, the employer shall provide the observer with that clothing and equipment and shall assure that the observer uses such clothing and equipment and complies with all other applicable safety and health procedures.
This section shall become effective December 14, 1992.
All obligations of this section commence on the effective date except as follows:
Except for small businesses (nineteen (19) or fewer employees), initial monitoring required by paragraph (d)(2) of this section shall be completed as soon as possible and in any event no later than 60 days after the effective date of this standard. For small businesses, initial monitoring required by paragraph (d)(2) of this section shall be completed as soon as possible and in any event no later than 120 days after the effective date of this standard.
Except for small business, defined under paragraph (p)(2)(i) of this section, regulated areas required to be established by paragraph (e) of this section shall be set up as soon as possible after the results of exposure monitoring are known and in any event no later than 90 days after the effective date of this section. For small businesses, regulated areas required to be established by paragraph (e) of this section shall be set up as soon as possible after the results of exposure monitoring are known and in any event no later than 150 days after the effective date of this section.
Except for small businesses, defined under paragraph (p)(2)(i) of this section, respiratory protection required by paragraph (g) of this section shall be provided as soon as possible and in any event no later than 90 days after the effective date of this section. For small businesses, respiratory protection required by paragraph (g) of this section shall be provided as soon as possible and in any event no later than 150 days after the effective date of this section.
Written compliance programs required by paragraph (f)(2) of this section shall be completed and available for inspection and copying as soon as possible and in any event no later than 1 year after the effective date of this section.
The engineering controls required by paragraph (f)(1) of this section shall be implemented as soon as possible and in any event no later than two (2) years after the effective date of this section. Work practice controls shall be implemented as soon as possible. Work practice controls that are directly related to engineering controls to be implemented in accordance with the compliance plan shall be implemented as soon as possible after such engineering controls are implemented.
Except for small businesses, defined under paragraph (p)(2)(i) of this section, employee information and training required by paragraph (m)(4) of this section shall be provided as soon as possible and in any event no later than 90 days after the effective date of this standard. For small businesses, employee information and training required by paragraph (m)(4) of this standard shall be provided as soon as possible and in any event no later than 180 days after the effective date of this standard.
Except for small businesses, defined under paragraph (p)(2)(i) of this section, initial medical examinations required by paragraph (l) of this section shall be provided as soon as possible and in any event no later than 90 days after the effective date of this standard. For small businesses, initial medical examinations required by paragraph (l) of this section shall be provided as soon as possible and in any event no later than 180 days after the effective date of this standard.
Except where portions of appendices A, B, D, E, and F to this section are expressly incorporated in requirements of this section, these appendices are purely informational and are not intended to create any additional obligations not otherwise imposed or to detract from any existing obligations.
Appendix A to § 1910.1027—Substance Safety Data Sheet
Cadmium
I. Substance Identification
A. Substance: Cadmium.
B. 8-Hour, Time-weighted-average, Permissible Exposure Limit (TWA PEL):
1. TWA PEL: Five micrograms of cadmium per cubic meter of air 5 µg/m 3, time-weighted average (TWA) for an 8-hour workday.
C. Appearance: Cadmium metal—soft, blue-white, malleable, lustrous metal or grayish-white powder. Some cadmium compounds may also appear as a brown, yellow, or red powdery substance.
II. Health Hazard Data
A. Routes of Exposure. Cadmium can cause local skin or eye irritation. Cadmium can affect your health if you inhale it or if you swallow it.
B. Effects of Overexposure.
1. Short-term (acute) exposure: Cadmium is much more dangerous by inhalation than by ingestion. High exposures to cadmium that may be immediately dangerous to life or health occur in jobs where workers handle large quantities of cadmium dust or fume; heat cadmium-containing compounds or cadmium-coated surfaces; weld with cadmium solders or cut cadmium-containing materials such as bolts.
2. Severe exposure may occur before symptoms appear. Early symptoms may include mild irritation of the upper respiratory tract, a sensation of constriction of the throat, a metallic taste and/or a cough. A period of 1-10 hours may precede the onset of rapidly progressing shortness of breath, chest pain, and flu-like symptoms with weakness, fever, headache, chills, sweating and muscular pain. Acute pulmonary edema usually develops within 24 hours and reaches a maximum by three days. If death from asphyxia does not occur, symptoms may resolve within a week.
3. Long-term (chronic) exposure. Repeated or long-term exposure to cadmium, even at relatively low concentrations, may result in kidney damage and an increased risk of cancer of the lung and of the prostate.
C. Emergency First Aid Procedures.
1. Eye exposure: Direct contact may cause redness or pain. Wash eyes immediately with large amounts of water, lifting the upper and lower eyelids. Get medical attention immediately.
2. Skin exposure: Direct contact may result in irritation. Remove contaminated clothing and shoes immediately. Wash affected area with soap or mild detergent and large amounts of water. Get medical attention immediately.
3. Ingestion: Ingestion may result in vomiting, abdominal pain, nausea, diarrhea, headache and sore throat. Treatment for symptoms must be administered by medical personnel. Under no circumstances should the employer allow any person whom he retains, employs, supervises or controls to engage in therapeutic chelation. Such treatment is likely to translocate cadmium from pulmonary or other tissue to renal tissue. Get medical attention immediately.
4. Inhalation: If large amounts of cadmium are inhaled, the exposed person must be moved to fresh air at once. If breathing has stopped, perform cardiopulmonary resuscitation. Administer oxygen if available. Keep the affected person warm and at rest. Get medical attention immediately.
5. Rescue: Move the affected person from the hazardous exposure. If the exposed person has been overcome, attempt rescue only after notifying at least one other person of the emergency and putting into effect established emergency procedures. Do not become a casualty yourself. Understand your emergency rescue procedures and know the location of the emergency equipment before the need arises.
III. Employee Information
A. Protective Clothing and Equipment.
1. Respirators: You may be required to wear a respirator for non-routine activities; in emergencies; while your employer is in the process of reducing cadmium exposures through engineering controls; and where engineering controls are not feasible. If respirators are worn in the future, they must have a joint Mine Safety and Health Administration (MSHA) and National Institute for Occupational Safety and Health (NIOSH) label of approval. Cadmium does not have a detectable odor except at levels well above the permissible exposure limits. If you can smell cadmium while wearing a respirator, proceed immediately to fresh air. If you experience difficulty breathing while wearing a respirator, tell your employer.
2. Protective Clothing: You may be required to wear impermeable clothing, gloves, foot gear, a face shield, or other appropriate protective clothing to prevent skin contact with cadmium. Where protective clothing is required, your employer must provide clean garments to you as necessary to assure that the clothing protects you adequately. The employer must replace or repair protective clothing that has become torn or otherwise damaged.
3. Eye Protection: You may be required to wear splash-proof or dust resistant goggles to prevent eye contact with cadmium.
B. Employer Requirements.
1. Medical: If you are exposed to cadmium at or above the action level, your employer is required to provide a medical examination, laboratory tests and a medical history according to the medical surveillance provisions under paragraph (1) of this standard. (See summary chart and tables in this appendix A.) These tests shall be provided without cost to you. In addition, if you are accidentally exposed to cadmium under conditions known or suspected to constitute toxic exposure to cadmium, your employer is required to make special tests available to you.
2. Access to Records: All medical records are kept strictly confidential. You or your representative are entitled to see the records of measurements of your exposure to cadmium. Your medical examination records can be furnished to your personal physician or designated representative upon request by you to your employer.
3. Observation of Monitoring: Your employer is required to perform measurements that are representative of your exposure to cadmium and you or your designated representative are entitled to observe the monitoring procedure. You are entitled to observe the steps taken in the measurement procedure, and to record the results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and equipment are required to be worn, you or your representative must also be provided with, and must wear the protective clothing and equipment.
C. Employee Requirements—You will not be able to smoke, eat, drink, chew gum or tobacco, or apply cosmetics while working with cadmium in regulated areas. You will also not be able to carry or store tobacco products, gum, food, drinks or cosmetics in regulated areas because these products easily become contaminated with cadmium from the workplace and can therefore create another source of unnecessary cadmium exposure.
Some workers will have to change out of work clothes and shower at the end of the day, as part of their workday, in order to wash cadmium from skin and hair. Handwashing and cadmium-free eating facilities shall be provided by the employer and proper hygiene should always be performed before eating. It is also recommended that you do not smoke or use tobacco products, because among other things, they naturally contain cadmium. For further information, read the labeling on such products.
IV. Physician Information
A. Introduction. The medical surveillance provisions of paragraph (1) generally are aimed at accomplishing three main interrelated purposes: First, identifying employees at higher risk of adverse health effects from excess, chronic exposure to cadmium; second, preventing cadmium-induced disease; and third, detecting and minimizing existing cadmium-induced disease. The core of medical surveillance in this standard is the early and periodic monitoring of the employee's biological indicators of: (a) Recent exposure to cadmium; (b) cadmium body burden; and (c) potential and actual kidney damage associated with exposure to cadmium.
The main adverse health effects associated with cadmium overexposure are lung cancer and kidney dysfunction. It is not yet known how to adequately biologically monitor human beings to specifically prevent cadmium-induced lung cancer. By contrast, the kidney can be monitored to provide prevention and early detection of cadmium-induced kidney damage. Since, for non-carcinogenic effects, the kidney is considered the primary target organ of chronic exposure to cadmium, the medical surveillance provisions of this standard effectively focus on cadmium-induced kidney disease. Within that focus, the aim, where possible, is to prevent the onset of such disease and, where necessary, to minimize such disease as may already exist. The by-products of successful prevention of kidney disease are anticipated to be the reduction and prevention of other cadmium-induced diseases.
B. Health Effects. The major health effects associated with cadmium overexposure are described below.
1. Kidney: The most prevalent non-malignant disease observed among workers chronically exposed to cadmium is kidney dysfunction. Initially, such dysfunction is manifested as proteinuria. The proteinuria associated with cadmium exposure is most commonly characterized by excretion of low-molecular weight proteins (15,000 to 40,000 MW) accompanied by loss of electrolytes, uric acid, calcium, amino acids, and phosphate. The compounds commonly excreted include: beta-2-microglobulin (β 2 -M), retinol binding protein (RBP), immunoglobulin light chains, and lysozyme. Excretion of low molecular weight proteins are characteristic of damage to the proximal tubules of the kidney (Iwao et al., 1980).
It has also been observed that exposure to cadmium may lead to urinary excretion of high-molecular weight proteins such as albumin, immunoglobulin G, and glycoproteins (Ex. 29). Excretion of high-molecular weight proteins is typically indicative of damage to the glomeruli of the kidney. Bernard et al., (1979) suggest that damage to the glomeruli and damage to the proximal tubules of the kidney may both be linked to cadmium exposure but they may occur independently of each other.
Several studies indicate that the onset of low-molecular weight proteinuria is a sign of irreversible kidney damage (Friberg et al., 1974; Roels et al., 1982; Piscator 1984; Elinder et al., 1985; Smith et al., 1986). Above specific levels of β 2 -M associated with cadmium exposure it is unlikely that β 2 -M levels return to normal even when cadmium exposure is eliminated by removal of the individual from the cadmium work environment (Friberg, Ex. 29, 1990).
Some studies indicate that such proteinuria may be progressive; levels of β 2 -M observed in the urine increase with time even after cadmium exposure has ceased. See, for example, Elinder et al., 1985. Such observations, however, are not universal, and it has been suggested that studies in which proteinuria has not been observed to progress may not have tracked patients for a sufficiently long time interval (Jarup, Ex. 8-661).
When cadmium exposure continues after the onset of proteinuria, chronic nephrotoxicity may occur (Friberg, Ex. 29). Uremia results from the inability of the glomerulus to adequately filter blood. This leads to severe disturbance of electrolyte concentrations and may lead to various clinical complications including kidney stones (L-140-50).
After prolonged exposure to cadmium, glomerular proteinuria, glucosuria, aminoaciduria, phosphaturia, and hypercalciuria may develop (Exs. 8-86, 4-28, 14-18). Phosphate, calcium, glucose, and amino acids are essential to life, and under normal conditions, their excretion should be regulated by the kidney. Once low molecular weight proteinuria has developed, these elements dissipate from the human body. Loss of glomerular function may also occur, manifested by decreased glomerular filtration rate and increased serum creatinine. Severe cadmium-induced renal damage may eventually develop into chronic renal failure and uremia (Ex. 55).
Studies in which animals are chronically exposed to cadmium confirm the renal effects observed in humans (Friberg et al., 1986). Animal studies also confirm problems with calcium metabolism and related skeletal effects which have been observed among humans exposed to cadmium in addition to the renal effects. Other effects commonly reported in chronic animal studies include anemia, changes in liver morphology, immunosuppression and hypertension. Some of these effects may be associated with co-factors. Hypertension, for example, appears to be associated with diet as well as cadmium exposure. Animals injected with cadmium have also shown testicular necrosis (Ex. 8-86B).
2. Biological Markers
It is universally recognized that the best measures of cadmium exposures and its effects are measurements of cadmium in biological fluids, especially urine and blood. Of the two, CdU is conventionally used to determine body burden of cadmium in workers without kidney disease. CdB is conventionally used to monitor for recent exposure to cadmium. In addition, levels of CdU and CdB historically have been used to predict the percent of the population likely to develop kidney disease (Thun et al., Ex. L-140-50; WHO, Ex. 8-674; ACGIH, Exs. 8-667, 140-50).
The third biological parameter upon which OSHA relies for medical surveillance is Beta-2-microglobulin in urine (β 2 -M), a low molecular weight protein. Excess β 2 -M has been widely accepted by physicians and scientists as a reliable indicator of functional damage to the proximal tubule of the kidney (Exs. 8-447, 144-3-C, 4-47, L-140-45, 19-43-A).
Excess β 2 -M is found when the proximal tubules can no longer reabsorb this protein in a normal manner. This failure of the proximal tubules is an early stage of a kind of kidney disease that commonly occurs among workers with excessive cadmium exposure. Used in conjunction with biological test results indicating abnormal levels of CdU and CdB, the finding of excess β 2 -M can establish for an examining physician that any existing kidney disease is probably cadmium-related (Trs. 6/6/90, pp. 82-86, 122, 134). The upper limits of normal levels for cadmium in urine and cadmium in blood are 3 µg Cd/gram creatinine in urine and 5 µgCd/liter whole blood, respectively. These levels were derived from broad-based population studies.
Three issues confront the physicians in the use of β 2 -M as a marker of kidney dysfunction and material impairment. First, there are a few other causes of elevated levels of β 2 -M not related to cadmium exposures, some of which may be rather common diseases and some of which are serious diseases (e.g., myeloma or transient flu, Exs. 29 and 8-086). These can be medically evaluated as alternative causes (Friberg, Ex. 29). Also, there are other factors that can cause β 2 -M to degrade so that low levels would result in workers with tubular dysfunction. For example, regarding the degradation of β 2 -M, workers with acidic urine (pH<6) might have β 2 -M levels that are within the “normal” range when in fact kidney dysfunction has occurred (Ex. L-140-1) and the low molecular weight proteins are degraded in acid urine. Thus, it is very important that the pH of urine be measured, that urine samples be buffered as necessary (See appendix F.), and that urine samples be handled correctly, i.e., measure the pH of freshly voided urine samples, then if necessary, buffer to pH>6 (or above for shipping purposes), measure pH again and then, perhaps, freeze the sample for storage and shipping. (See also appendix F.) Second, there is debate over the pathological significance of proteinuria, however, most world experts believe that β 2 -M levels greater than 300 µg/g Cr are abnormal (Elinder, Ex. 55, Friberg, Ex. 29). Such levels signify kidney dysfunction that constitutes material impairment of health. Finally, detection of β 2 -M at low levels has often been considered difficult, however, many laboratories have the capability of detecting excess β 2 -M using simple kits, such as the Phadebas Delphia test, that are accurate to levels of 100 µg β 2 -M/g Cr U (Ex. L-140-1).
Specific recommendations for ways to measure β 2 -M and proper handling of urine samples to prevent degradation of β 2 -M have been addressed by OSHA in appendix F, in the section on laboratory standardization. All biological samples must be analyzed in a laboratory that is proficient in the analysis of that particular analyte, under paragraph (l)(1)(iv). (See appendix F). Specifically, under paragraph (l)(1)(iv), the employer is to assure that the collecting and handling of biological samples of cadmium in urine (CdU), cadmium in blood (CdB), and beta-2 microglobulin in urine (β 2 -M) taken from employees is collected in a manner that assures reliability. The employer must also assure that analysis of biological samples of cadmium in urine (CdU), cadmium in blood (CdB), and beta-2 microglobulin in urine (β 2 -M) taken from employees is performed in laboratories with demonstrated proficiency for that particular analyte. (See appendix F.)
3. Lung and Prostate Cancer
The primary sites for cadmium-associated cancer appear to be the lung and the prostate (L-140-50). Evidence for an association between cancer and cadmium exposure derives from both epidemiological studies and animal experiments. Mortality from prostate cancer associated with cadmium is slightly elevated in several industrial cohorts, but the number of cases is small and there is not clear dose-response relationship. More substantive evidence exists for lung cancer.
The major epidemiological study of lung cancer was conducted by Thun et al., (Ex. 4-68). Adequate data on cadmium exposures were available to allow evaluation of dose-response relationships between cadmium exposure and lung cancer. A statistically significant excess of lung cancer attributed to cadmium exposure was observed in this study even when confounding variables such as co-exposure to arsenic and smoking habits were taken into consideration (Ex. L-140-50).
The primary evidence for quantifying a link between lung cancer and cadmium exposure from animal studies derives from two rat bioassay studies; one by Takenaka et al., (1983), which is a study of cadmium chloride and a second study by Oldiges and Glaser (1990) of four cadmium compounds.
Based on the above cited studies, the U.S. Environmental Protection Agency (EPA) classified cadmium as “B1”, a probable human carcinogen, in 1985 (Ex. 4-4). The International Agency for Research on Cancer (IARC) in 1987 also recommended that cadmium be listed as “2A”, a probable human carcinogen (Ex. 4-15). The American Conference of Governmental Industrial Hygienists (ACGIH) has recently recommended that cadmium be labeled as a carcinogen. Since 1984, NIOSH has concluded that cadmium is possibly a human carcinogen and has recommended that exposures be controlled to the lowest level feasible.
4. Non-carcinogenic Effects
Acute pneumonitis occurs 10 to 24 hours after initial acute inhalation of high levels of cadmium fumes with symptoms such as fever and chest pain (Exs. 30, 8-86B). In extreme exposure cases pulmonary edema may develop and cause death several days after exposure. Little actual exposure measurement data is available on the level of airborne cadmium exposure that causes such immediate adverse lung effects, nonetheless, it is reasonable to believe a cadmium concentration of approximately 1 mg/m 3 over an eight hour period is “immediately dangerous” (55 FR 4052, ANSI; Ex. 8-86B).
In addition to acute lung effects and chronic renal effects, long term exposure to cadmium may cause other severe effects on the respiratory system. Reduced pulmonary function and chronic lung disease indicative of emphysema have been observed in workers who have had prolonged exposure to cadmium dust or fumes (Exs. 4-29, 4-22, 4-42, 4-50, 4-63). In a study of workers conducted by Kazantzis et al., a statistically significant excess of worker deaths due to chronic bronchitis was found, which in his opinion was directly related to high cadmium exposures of 1 mg/m 3 or more (Tr. 6/8/90, pp. 156-157).
Cadmium need not be respirable to constitute a hazard. Inspirable cadmium particles that are too large to be respirable but small enough to enter the tracheobronchial region of the lung can lead to bronchoconstriction, chronic pulmonary disease, and cancer of that portion of the lung. All of these diseases have been associated with occupational exposure to cadmium (Ex. 8-86B). Particles that are constrained by their size to the extra-thoracic regions of the respiratory system such as the nose and maxillary sinuses can be swallowed through mucocillary clearance and be absorbed into the body (ACGIH, Ex. 8-692). The impaction of these particles in the upper airways can lead to anosmia, or loss of sense of smell, which is an early indication of overexposure among workers exposed to heavy metals. This condition is commonly reported among cadmium-exposed workers (Ex. 8-86-B).
C. Medical Surveillance
In general, the main provisions of the medical surveillance section of the standard, under paragraphs (l)(1)-
1. Workers exposed above the action level are covered;
2. Workers with intermittent exposures are not covered;
3. Past workers who are covered receive biological monitoring for at least one year;
4. Initial examinations include a medical questionnaire and biological monitoring of cadmium in blood (CdB), cadmium in urine (CdU), and Beta-2-microglobulin in urine (β 2 -M);
5. Biological monitoring of these three analytes is performed at least annually; full medical examinations are performed biennially;
6. Until five years from the effective date of the standard, medical removal is required when CdU is greater than 15 µg/gram creatinine (g Cr), or CdB is greater than 15 µg/liter whole blood (lwb), or β 2 -M is greater than 1500 µg/g Cr, and CdB is greater than 5 µg/lwb or CdU is greater than 3 µg/g Cr;
7. Beginning five years after the standard is in effect, medical removal triggers will be reduced;
8. Medical removal protection benefits are to be provided for up to 18 months;
9. Limited initial medical examinations are required for respirator usage;
10. Major provisions are fully described under section (l) of the regulatory text; they are outlined here as follows:
A. Eligibility
B. Biological monitoring
2
D. Periodic medical surveillance
E. Actions triggered by periodic medical surveillance (See appendix A Summary Chart and Tables in Attachment-1.)
F. Respirator usage
G. Emergency medical examinations
H. Termination examination
I. Information to physician
J. Physician's medical opinion
K. Medical removal protection
L. Medical removal protection benefits
M. Multiple physician review
N. Alternate physician review
O. Information employer gives to employee
P. Recordkeeping
Q. Reporting on OSHA form 200
11. The above mentioned summary of the medical surveillance provisions, the summary chart, and tables for the actions triggered at different levels of CdU, CdB and β 2 -M (in appendix A Attachment-1) are included only for the purpose of facilitating understanding of the provisions of paragraphs (l)(3) of the final cadmium standard. The summary of the provisions, the summary chart, and the tables do not add to or reduce the requirements in paragraph (l)(3).
D. Recommendations to Physicians
1. It is strongly recommended that patients with tubular proteinuria are counseled on: The hazards of smoking; avoidance of nephrotoxins and certain prescriptions and over-the-counter medications that may exacerbate kidney symptoms; how to control diabetes and/or blood pressure; proper hydration, diet, and exercise (Ex. 19-2). A list of prominent or common nephrotoxins is attached. (See appendix A Attachment-2.)
2. DO NOT CHELATE; KNOW WHICH DRUGS ARE NEPHROTOXINS OR ARE ASSOCIATED WITH NEPHRITIS.
3. The gravity of cadmium-induced renal damage is compounded by the fact there is no medical treatment to prevent or reduce the accumulation of cadmium in the kidney (Ex. 8-619). Dr. Friberg, a leading world expert on cadmium toxicity, indicated in 1992, that there is no form of chelating agent that could be used without substantial risk. He stated that tubular proteinuria has to be treated in the same way as other kidney disorders (Ex. 29).
4. After the results of a workers' biological monitoring or medical examination are received the employer is required to provide an information sheet to the patient, briefly explaining the significance of the results. (See Attachment 3 of this appendix A.)
5. For additional information the physician is referred to the following additional resources:
a. The physician can always obtain a copy of the preamble, with its full discussion of the health effects, from OSHA's Computerized Information System (OCIS).
b. The Docket Officer maintains a record of the rulemaking. The Cadmium Docket (H-057A), is located at 200 Constitution Ave. NW., room N-2625, Washington, DC 20210; telephone: 202-219-7894.
c. The following articles and exhibits in particular from that docket (H-057A):
| Exhibit number | Author and paper title |
|---|---|
| 8-447 | Lauwerys et. al., Guide for physicians, “Health Maintenance of Workers Exposed to Cadmium,” published by the Cadmium Council. |
| 4-67 | Takenaka, S., H. Oldiges, H. Konig, D. Hochrainer, G. Oberdorster. “Carcinogenicity of Cadmium Chloride Aerosols in Wistar Rats”. JNCI 70:367-373, 1983. (32) |
| 4-68 | Thun, M.J., T.M. Schnoor, A.B. Smith, W.E. Halperin, R.A. Lemen. “Mortality Among a Cohort of U.S. Cadmium Production Workers—An Update.” JNCI 74(2):325-33, 1985. (8) |
| 4-25 | Elinder, C.G., Kjellstrom, T., Hogstedt, C., et al. , “Cancer Mortality of Cadmium Workers.” Brit. J. Ind. Med. 42:651-655, 1985. (14) |
| 4-26 | Ellis, K.J. et al., “Critical Concentrations of Cadmium in Human Renal Cortex: Dose Effect Studies to Cadmium Smelter Workers.” J. Toxicol. Environ. Health 7:691-703, 1981. (76) |
| 4-27 | Ellis, K.J., S.H. Cohn and T.J. Smith. “Cadmium Inhalation Exposure Estimates: Their Significance with Respect to Kidney and Liver Cadmium Burden.” J. Toxicol. Environ. Health 15:173-187, 1985. |
| 4-28 | Falck, F.Y., Jr., Fine, L.J., Smith, R.G., McClatchey, K.D., Annesley, T., England, B., and Schork, A.M. “Occupational Cadmium Exposure and Renal Status.” Am. J. Ind. Med. 4:541, 1983. (64) |
| 8-86A | Friberg, L., C.G. Elinder, et al. , “Cadmium and Health a Toxicological and Epidemiological Appraisal, Volume I, Exposure, Dose, and Metabolism.” CRC Press, Inc., Boca Raton, FL, 1986. (Available from the OSHA Technical Data Center) |
| 8-86B | Friberg, L., C.G. Elinder, et al. , “Cadmium and Health: A Toxicological and Epidemiological Appraisal, Volume II, Effects and Response.” CRC Press, Inc., Boca Raton, FL, 1986. (Available from the OSHA Technical Data Center) |
| L-140-45 | Elinder, C.G., “Cancer Mortality of Cadmium Workers”, Brit. J. Ind. Med., 42, 651-655, 1985. |
| L-140-50 | Thun, M., Elinder, C.G., Friberg, L, “Scientific Basis for an Occupational Standard for Cadmium, Am. J. Ind. Med. , 20; 629-642, 1991. |
V. Information Sheet
The information sheet (appendix A Attachment-3.) or an equally explanatory one should be provided to you after any biological monitoring results are reviewed by the physician, or where applicable, after any medical examination.
Attachment 1—Appendix A Summary Chart and Tables A and B of Actions Triggered by Biological Monitoring
Appendix A Summary Chart: Section (1)(3) Medical Surveillance
Categorizing Biological Monitoring Results
Actions Triggered by Biological Monitoring
Appendix A Table A—Categorization of Biological Monitoring Results
| Biological marker | Monitoring result categories | ||
|---|---|---|---|
| A | B | C | |
| Cadmium in urine (CdU) (µg/g creatinine) | ≤3 | >3 and ≤15 | >15 |
| β 2 -microglobulin (β 2 -M) (µg/g creatinine) | ≤300 | >300 and ≤1500 | >1500* |
| Cadmium in blood (CdB) (µg/liter whole blood) | ≤5 | >5 and ≤15 | >15 |
| * If an employee's β 2 -M levels are above 1,500 µg/g creatinine, in order for mandatory medical removal to be required (See appendix A Table B.), either the employee's CdU level must also be >3 µg/g creatinine or CdB level must also be >5 µg/liter whole blood. |
| Biological marker | Monitoring result categories | ||
|---|---|---|---|
| A | B | C | |
| Cadmium in urine (CdU) (µg/g creatinine) | ≤3 | >3 and ≤7 | >7 |
| β 2 -microglobulin (β 2 -M) (µg/g creatinine) | ≤300 | >300 and ≤750 | >750* |
| Cadmium in blood (CdB) (µg/liter whole blood) | ≤5 | >5 and ≤10 | >10 |
| * If an employee's β 2 -M levels are above 750 µg/g creatinine, in order for mandatory medical removal to be required (See appendix A Table B.), either the employee's CdU level must also be >3 µg/g creatinine or CdB level must also be >5 µg/liter whole blood. |
Appendix A Table B—Actions Determined by Biological Monitoring
This table presents the actions required based on the monitoring result in appendix A Table A. Each item is a separate requirement in citing non-compliance. For example, a medical examination within 90 days for an employee in category B is separate from the requirement to administer a periodic medical examination for category B employees on an annual basis.
| Required actions | Monitoring result category | |
|---|---|---|
| A 1 | B 1 | C 1 |
| (1) Biological monitoring: | ||
| (a) Annual. | X | |
| (b) Semiannual | X | |
| (c) Quarterly | X | |
| (2) Medical examination: | ||
| (a) Biennial | X | |
| (b) Annual. | X | |
| (c) Semiannual. | X | |
| (d) Within 90 days | X | X |
| (3) Assess within two weeks: | ||
| (a) Excess cadmium exposure | X | X |
| (b) Work practices | X | X |
| (c) Personal hygiene | X | X |
| (d) Respirator usage | X | X |
| (e) Smoking history | X | X |
| (f) Hygiene facilities | X | X |
| (g) Engineering controls | X | X |
| (h) Correct within 30 days | X | X |
| (i) Periodically assess exposures | X | |
| (4) Discretionary medical removal | X | X |
| (5) Mandatory medical removal | X 2 | |
| 1 For all employees covered by medical surveillance exclusively because of exposures prior to the effective date of this standard, if they are in Category A, the employer shall follow the requirements of paragraphs (l)(3)(i)(B) and (l)(4)(v)(A). If they are in Category B or C, the employer shall follow the requirements of paragraphs (l)(4)(v)(B)-(C). | ||
| 2 See footnote appendix A Table A. |
Appendix A—Attachment 2—List of Medications
A list of the more common medications that a physician, and the employee, may wish to review is likely to include some of the following: (1) Anticonvulsants: Paramethadione, phenytoin, trimethadone; (2) antihypertensive drugs: Captopril, methyldopa; (3) antimicrobials: Aminoglycosides, amphotericin B, cephalosporins, ethambutol; (4) antineoplastic agents: Cisplatin, methotrexate, mitomycin-C, nitrosoureas, radiation; (4) sulfonamide diuretics: Acetazolamide, chlorthalidone, furosemide, thiazides; (5) halogenated alkanes, hydrocarbons, and solvents that may occur in some settings: Carbon tetrachloride, ethylene glycol, toluene; iodinated radiographic contrast media; nonsteroidal anti-inflammatory drugs; and, (7) other miscellaneous compounds: Acetominophen, allopurinol, amphetamines, azathioprine, cimetidine, cyclosporine, lithium, methoxyflurane, methysergide, D-penicillamine, phenacetin, phenendione. A list of drugs associated with acute interstitial nephritis includes: (1) Antimicrobial drugs: Cephalosporins, chloramphenicol, colistin, erythromycin, ethambutol, isoniazid, para-aminosalicylic acid, penicillins, polymyxin B, rifampin, sulfonamides, tetracyclines, and vancomycin; (2) other miscellaneous drugs: Allopurinol, antipyrene, azathioprine, captopril, cimetidine, clofibrate, methyldopa, phenindione, phenylpropanolamine, phenytoin, probenecid, sulfinpyrazone, sulfonamid diuretics, triamterene; and, (3) metals: Bismuth, gold.
This list have been derived from commonly available medical textbooks (e.g., Ex. 14-18). The list has been included merely to facilitate the physician's, employer's, and employee's understanding. The list does not represent an official OSHA opinion or policy regarding the use of these medications for particular employees. The use of such medications should be under physician discretion.
Attachment 3—Biological Monitoring and Medical Examination Results
Employee
Testing Date
Cadmium in Urine ___ µg/g Cr—Normal Levels: ≤3 µg/g Cr.
Cadmium in Blood ___ µg/lwb—Normal Levels: ≤5 µg/lwb.
Beta-2-microglobulin in Urine ___ µg/g Cr—Normal Levels: ≤300 µg/g Cr.
Physical Examination Results: N/A ___ Satisfactory ___ Unsatisfactory ___ (see physician again).
Physician's Review of Pulmonary Function Test: N/A ___ Normal ___ Abnormal ___.
Next biological monitoring or medical examination scheduled for
The biological monitoring program has been designed for three main purposes: 1) to identify employees at risk of adverse health effects from excess, chronic exposure to cadmium; 2) to prevent cadmium-induced disease(s); and 3) to detect and minimize existing cadmium-induced disease(s).
The levels of cadmium in the urine and blood provide an estimate of the total amount of cadmium in the body. The amount of a specific protein in the urine (beta-2-microglobulin) indicates changes in kidney function. All three tests must be evaluated together. A single mildly elevated result may not be important if testing at a later time indicates that the results are normal and the workplace has been evaluated to decrease possible sources of cadmium exposure. The levels of cadmium or beta-2-microglobulin may change over a period of days to months and the time needed for those changes to occur is different for each worker.
If the results for biological monitoring are above specific “high levels” [cadmium urine greater than 10 micrograms per gram of creatinine (µg/g Cr), cadmium blood greater than 10 micrograms per liter of whole blood (µg/lwb), or beta-2-microglobulin greater than 1000 micrograms per gram of creatinine (µg/g Cr)], the worker has a much greater chance of developing other kidney diseases.
One way to measure for kidney function is by measuring beta-2-microglobulin in the urine. Beta-2-microglobulin is a protein which is normally found in the blood as it is being filtered in the kidney, and the kidney reabsorbs or returns almost all of the beta-2-microglobulin to the blood. A very small amount (less than 300 µg/g Cr in the urine) of beta-2-microglobulin is not reabsorbed into the blood, but is released in the urine. If cadmium damages the kidney, the amount of beta-2-microglobulin in the urine increases because the kidney cells are unable to reabsorb the beta-2-microglobulin normally. An increase in the amount of beta-2-microglobulin in the urine is a very early sign of kidney dysfunction. A small increase in beta-2-microglobulin in the urine will serve as an early warning sign that the worker may be absorbing cadmium from the air, cigarettes contaminated in the workplace, or eating in areas that are cadmium contaminated.
Even if cadmium causes permanent changes in the kidney's ability to reabsorb beta-2-microglobulin, and the beta-2-microglobulin is above the “high levels”, the loss of kidney function may not lead to any serious health problems. Also, renal function naturally declines as people age. The risk for changes in kidney function for workers who have biological monitoring results between the “normal values” and the “high levels” is not well known. Some people are more cadmium-tolerant, while others are more cadmium-susceptible.
For anyone with even a slight increase of beta-2-microglobulin, cadmium in the urine, or cadmium in the blood, it is very important to protect the kidney from further damage. Kidney damage can come from other sources than excess cadmium-exposure so it is also recommended that if a worker's levels are “high” he/she should receive counseling about drinking more water; avoiding cadmium-tainted tobacco and certain medications (nephrotoxins, acetaminophen); controlling diet, vitamin intake, blood pressure and diabetes; etc.
Appendix B to § 1910.1027—Substance Technical Guidelines for Cadmium
I. Cadmium Metal
A. Physical and Chemical Data.
1. Substance Identification.
Chemical name: Cadmium.
Formula: Cd.
Molecular Weight: 112.4.
Chemical Abstracts Service (CAS) Registry No.: 7740-43-9.
Other Identifiers: RETCS EU9800000; EPA D006; DOT 2570 53.
Synonyms: Colloidal Cadmium: Kadmium (German): CI 77180.
2. Physical data.
Boiling point: (760 mm Hg): 765 degrees C.
Melting point: 321 degrees C.
Specific Gravity: (H 2 O=@ 20 °C): 8.64.
Solubility: Insoluble in water; soluble in dilute nitric acid and in sulfuric acid.
Appearance: Soft, blue-white, malleable, lustrous metal or grayish-white powder.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: The finely divided metal is pyrophoric, that is the dust is a severe fire hazard and moderate explosion hazard when exposed to heat or flame. Burning material reacts violently with extinguishing agents such as water, foam, carbon dioxide, and halons.
Flash point: Flammable (dust).
Extinguishing media: Dry sand, dry dolomite, dry graphite, or sodimum chloride.
2. Reactivity.
Conditions contributing to instability: Stable when kept in sealed containers under normal temperatures and pressure, but dust may ignite upon contact with air. Metal tarnishes in moist air.
Incompatibilities: Ammonium nitrate, fused: Reacts violently or explosively with cadmium dust below 20 °C. Hydrozoic acid: Violent explosion occurs after 30 minutes. Acids: Reacts violently, forms hydrogen gas. Oxidizing agents or metals: Strong reaction with cadmium dust. Nitryl fluoride at slightly elevated temperature: Glowing or white incandescence occurs. Selenium: Reacts exothermically. Ammonia: Corrosive reaction. Sulfur dioxide: Corrosive reaction. Fire extinguishing agents (water, foam, carbon dioxide, and halons): Reacts violently. Tellurium: Incandescent reaction in hydrogen atmosphere.
Hazardous decomposition products: The heated metal rapidly forms highly toxic, brownish fumes of oxides of cadmium.
C. Spill, Leak and Disposal Procedures.
1. Steps to be taken if the materials is released or spilled. Do not touch spilled material. Stop leak if you can do it without risk. Do not get water inside container. For large spills, dike spill for later disposal. Keep unnecessary people away. Isolate hazard area and deny entry. The Superfund Amendments and Reauthorization Act of 1986 Section 304 requires that a release equal to or greater than the reportable quantity for this substance (1 pound) must be immediately reported to the local emergency planning committee, the state emergency response commission, and the National Response Center (800) 424-8802; in Washington, DC metropolitan area (202) 426-2675.
II. Cadmium Oxide
A. Physical and Chemical Date.
1. Substance identification.
Chemical name: Cadmium Oxide.
Formula: CdO.
Molecular Weight: 128.4.
CAS No.: 1306-19-0.
Other Identifiers: RTECS EV1929500.
Synonyms: Kadmu tlenek (Polish).
2. Physical data.
Boiling point (760 mm Hg): 950 degrees C decomposes.
Melting point: 1500 °C.
Specific Gravity: (H 2 O = 1@20 °C): 7.0.
Solubility: Insoluble in water; soluble in acids and alkalines.
Appearance: Red or brown crystals.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: Negligible fire hazard when exposed to heat or flame.
Flash point: Nonflammable.
Extinguishing media: Dry chemical, carbon dioxide, water spray or foam.
2. Reactivity.
Conditions contributing to instability: Stable under normal temperatures and pressures.
Incompatibilities: Magnesium may reduce CdO 2 explosively on heating.
Hazardous decomposition products: Toxic fumes of cadmium.
C. Spill Leak and Disposal Procedures.
1. Steps to be taken if the material is released or spilled. Do not touch spilled material. Stop leak if you can do it without risk. For small spills, take up with sand or other absorbent material and place into containers for later disposal. For small dry spills, use a clean shovel to place material into clean, dry container and then cover. Move containers from spill area. For larger spills, dike far ahead of spill for later disposal. Keep unnecessary people away. Isolate hazard area and deny entry. The Superfund Amendments and Reauthorization Act of 1986 Section 304 requires that a release equal to or greater than the reportable quantity for this substance (1 pound) must be immediately reported to the local emergency planning committee, the state emergency response commission, and the National Response Center (800) 424-8802; in Washington, DC metropolitan area (202) 426-2675.
III. Cadmium Sulfide.
A. Physical and Chemical Data.
1. Substance Identification.
Chemical name: Cadmium sulfide.
Formula: CdS.
Molecular weight: 144.5.
CAS No. 1306-23-6.
Other Identifiers: RTECS EV3150000.
Synonyms: Aurora yellow; Cadmium Golden 366; Cadmium Lemon Yellow 527; Cadmium Orange; Cadmium Primrose 819; Cadmium Sulphide; Cadmium Yellow; Cadmium Yellow 000; Cadmium Yellow Conc. Deep; Cadmium Yellow Conc. Golden; Cadmium Yellow Conc. Lemon; Cadmium Yellow Conc. Primrose; Cadmium Yellow Oz. Dark; Cadmium Yellow Primrose 47-1400; Cadmium Yellow 10G Conc.; Cadmium Yellow 892; Cadmopur Golden Yellow N; Cadmopur Yellow: Capsebon; C.I. 77199; C.I. Pigment Orange 20; CI Pigment Yellow 37; Ferro Lemon Yellow; Ferro Orange Yellow; Ferro Yellow; Greenockite; NCI-C02711.
2. Physical data.
Boiling point (760 mm. Hg): sublines in N 2 at 980 °C.
Melting point: 1750 degrees C (100 atm).
Specific Gravity: (H 2 O = 1@ 20 °C): 4.82.
Solubility: Slightly soluble in water; soluble in acid.
Appearance: Light yellow or yellow-orange crystals.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: Neglible fire hazard when exposed to heat or flame.
Flash point: Nonflammable.
Extinguishing media: Dry chemical, carbon dioxide, water spray or foam.
2. Reactivity.
Conditions contributing to instability: Generally non-reactive under normal conditions. Reacts with acids to form toxic hydrogen sulfide gas.
Incompatibilities: Reacts vigorously with iodinemonochloride.
Hazardous decomposition products: Toxic fumes of cadmium and sulfur oxides.
C. Spill Leak and Disposal Procedures.
1. Steps to be taken if the material is released or spilled. Do not touch spilled material. Stop leak if you can do it without risk. For small, dry spills, with a clean shovel place material into clean, dry container and cover. Move containers from spill area. For larger spills, dike far ahead of spill for later disposal. Keep unnecessary people away. Isolate hazard and deny entry.
IV. Cadmium Chloride.
A. Physical and Chemical Data.
1. Substance Identification.
Chemcail name: Cadmium chloride.
Formula: CdC1 2.
Molecular weight: 183.3.
CAS No. 10108-64-2.
Other Identifiers: RTECS EY0175000.
Synonyms: Caddy; Cadmium dichloride; NA 2570 (DOT); UI-CAD; dichlorocadmium.
2. Physical data.
Boiling point (760 mm Hg): 960 degrees C.
Melting point: 568 degrees C.
Specific Gravity: (H 2 O = 1 @ 20 °C): 4.05.
Solubility: Soluble in water (140 g/100 cc); soluble in acetone.
Appearance: Small, white crystals.
B. Fire, Explosion and Reactivity Data.
1. Fire.
Fire and Explosion Hazards: Negligible fire and negligible explosion hazard in dust form when exposed to heat or flame.
Flash point: Nonflamable.
Extinguishing media: Dry chemical, carbon dioxide, water spray or foam.
2. Reactivity.
Conditions contributing to instability: Generally stable under normal temperatures and pressures.
Incompatibilities: Bromine trifluoride rapidly attacks cadmium chloride. A mixture of potassium and cadmium chloride may produce a strong explosion on impact.
Hazardous decomposition products: Thermal ecompostion may release toxic fumes of hydrogen chloride, chloride, chlorine or oxides of cadmium.
C. Spill Leak and Disposal Procedures.
1. Steps to be taken if the materials is released or spilled. Do not touch spilled material. Stop leak if you can do it without risk. For small, dry spills, with a clean shovel place material into clean, dry container and cover. Move containers from spill area. For larger spills, dike far ahead of spill for later disposal. Keep unnecessary people away. Isolate hazard and deny entry. The Superfund Amendments and Reauthorization Act of 1986 Section 304 requires that a release equal to or greater than the reportable quantity for this substance (100 pounds) must be immediately reported to the local emergency planning committee, the state emergency response commission, and the National Response Center (800) 424-8802; in Washington, DC Metropolitan area (202) 426-2675.
Appendix E to § 1910.1027—Cadmium in Workplace Atmospheres
Method Number: ID-189
Matrix: Air
3
3
Collection Procedure: A known volume of air is drawn through a 37-mm diameter filter cassette containing a 0.8-µm mixed cellulose ester membrane filter (MCEF).
Recommended Air Volume: 960 L
Recommended Sampling Rate: 2.0 L/min
Analytical Procedure: Air filter samples are digested with nitric acid. After digestion, a small amount of hydrochloric acid is added. The samples are then diluted to volume with deionized water and analyzed by either flame atomic absorption spectroscopy (AAS) or flameless atomic absorption spectroscopy using a heated graphite furnace atomizer (AAS-HGA).
Detection Limits:
3
3
3
3
Precision and Accuracy: (Flame AAS Analysis and AAS-HGA Analysis):
3
3
1
Analytical Bias: + 4.0%, −5.8%
Overall Analytical Error:±6.0%, ±14.2%
Method Classification: Validated
Date: June, 1992
Inorganic Service Branch II, OSHA Salt Lake Technical Center, Salt Lake City, Utah
Commercial manufacturers and products mentioned in this method are for descriptive use only and do not constitute endorsements by USDOL-OSHA. Similar products from other sources can be substituted.
1. Introduction
1.1. Scope
This method describes the collection of airborne elemental cadmium and cadmium compounds on 0.8-µm mixed cellulose ester membrane filters and their subsequent analysis by either flame atomic absorption spectroscopy (AAS) or flameless atomic absorption spectroscopy using a heated graphite furnace atomizer (AAS-HGA). It is applicable for both TWA and Action Level TWA Permissible Exposure Level (PEL) measurements. The two atomic absorption analytical techniques included in the method do not differentiate between cadmium fume and cadmium dust samples. They also do not differentiate between elemental cadmium and its compounds.
1.2. Principle
Airborne elemental cadmium and cadmium compounds are collected on a 0.8-µm mixed cellulose ester membrane filter (MCEF). The air filter samples are digested with concentrated nitric acid to destroy the organic matrix and dissolve the cadmium analytes. After digestion, a small amount of concentrated hydrochloric acid is added to help dissolve other metals which may be present. The samples are diluted to volume with deionized water and then aspirated into the oxidizing air/acetylene flame of an atomic absorption spectrophotometer for analysis of elemental cadmium.
If the concentration of cadmium in a sample solution is too low for quantitation by this flame AAS analytical technique, and the sample is to be averaged with other samples for TWA calculations, aliquots of the sample and a matrix modifier are later injected onto a L'vov platform in a pyrolytically-coated graphite tube of a Zeeman atomic absorption spectrophotometer/graphite furnace assembly for analysis of elemental cadmium. The matrix modifier is added to stabilize the cadmium metal and minimize sodium chloride as an interference during the high temperature charring step of the analysis (5.1., 5.2.).
1.3. History
Previously, two OSHA sampling and analytical methods for cadmium were used concurrently (5.3., 5.4.). Both of these methods also required 0.8-µm mixed cellulose ester membrane filters for the collection of air samples. These cadmium air filter samples were analyzed by either flame atomic absorption spectroscopy (5.3.) or inductively coupled plasma/atomic emission spectroscopy (ICP-AES) (5.4.). Neither of these two analytical methods have adequate sensitivity for measuring workplace exposure to airborne cadmium at the new lower TWA and Action Level TWA PEL levels when consecutive samples are taken on one employee and the sample results need to be averaged with other samples to determine a single TWA.
The inclusion of two atomic absorption analytical techniques in the new sampling and analysis method for airborne cadmium permits quantitation of sample results over a broad range of exposure levels and sampling periods. The flame AAS analytical technique included in this method is similar to the previous procedure given in the General Metals Method ID-121 (5.3.) with some modifications. The sensitivity of the AAS-HGA analytical technique included in this method is adequate to measure exposure levels at 1/10 the Action Level TWA, or lower, when less than full-shift samples need to be averaged together.
1.4. Properties (5.5.)
Elemental cadmium is a silver-white, blue-tinged, lustrous metal which is easily cut with a knife. It is slowly oxidized by moist air to form cadmium oxide. It is insoluble in water, but reacts readily with dilute nitric acid. Some of the physical properties and other descriptive information of elemental cadmium are given below:
CAS No.
7440-43-9
Atomic Number
48
Atomic Symbol
Cd
Atomic Weight
112.41
Melting Point
321 °C
Boiling Point
765 °C
Density
8.65 g/mL (25 °C)
The properties of specific cadmium compounds are described in reference 5.5.
1.5. Method Performance
A synopsis of method performance is presented below. Further information can be found in Section 4.
1.5.1. The qualitative and quantitative detection limits for the flame AAS analytical technique are 0.04 µg (0.004 µg/mL) and 0.14 µg (0.014 µg/mL) cadmium, respectively, for a 10 mL solution volume. These correspond, respectively, to 0.2 µg/m 3 and 0.70 µg/m 3 for a 200 L air volume.
1.5.2. The qualitative and quantitative detection limits for the AAS-HGA analytical technique are 0.44 ng (0.044 ng/mL) and 1.5 ng (0.15 ng/mL) cadmium, respectively, for a 10 mL solution volume. These correspond, respectively, to 0.007 µg/m 3 and 0.025 µg/m 3 for a 60 L air volume.
1.5.3. The average recovery by the flame AAS analytical technique of 17 spiked MCEF samples containing cadmium in the range of 0.5 to 2.0 times the TWA target concentration of 5 µg/m 3 (assuming a 400 L air volume) was 104.0% with a pooled coefficient of variation (CV 1 ) of 0.010. The flame analytical technique exhibited a positive bias of + 4.0% for the validated concentration range. The overall analytical error (OAE) for the flame AAS analytical technique was ±6.0%.
1.5.4. The average recovery by the AAS-HGA analytical technique of 18 spiked MCEF samples containing cadmium in the range of 0.5 to 2.0 times the Action Level TWA target concentration of 2.5 µg/m 3 (assuming a 60 L air volume) was 94.2% with a pooled coefficient of variation (CV 1 ) of 0.043. The AAS-HGA analytical technique exhibited a negative bias of −5.8% for the validated concentration range. The overall analytical error (OAE) for the AAS-HGA analytical technique was ±14.2%.
1.5.5. Sensitivity in flame atomic absorption is defined as the characteristic concentration of an element required to produce a signal of 1% absorbance (0.0044 absorbance units). Sensitivity values are listed for each element by the atomic absorption spectrophotometer manufacturer and have proved to be a very valuable diagnostic tool to determine if instrumental parameters are optimized and if the instrument is performing up to specification. The sensitivity of the spectrophotometer used in the validation of the flame AAS analytical technique agreed with the manufacturer specifications (5.6.); the 2 µg/mL cadmium standard gave an absorbance reading of 0.350 abs. units.
1.5.6. Sensitivity in graphite furnace atomic absorption is defined in terms of the characteristic mass, the number of picograms required to give an integrated absorbance value of 0.0044 absorbance-second (5.7.). Data suggests that under Stabilized Temperature Platform Furnace (STPF) conditions (see Section 1.6.2.), characteristic mass values are transferable between properly functioning instruments to an accuracy of about 20% (5.2.). The characteristic mass for STPF analysis of cadmium with Zeeman background correction listed by the manufacturer of the instrument used in the validation of the AAS-HGA analytical technique was 0.35 pg. The experimental characteristic mass value observed during the determination of the working range and detection limits of the AAS-HGA analytical technique was 0.41 pg.
1.6. Interferences
1.6.1. High concentrations of silicate interfere in determining cadmium by flame AAS (5.6.). However, silicates are not significantly soluble in the acid matrix used to prepare the samples.
1.6.2. Interferences, such as background absorption, are reduced to a minimum in the AAS-HGA analytical technique by taking full advantage of the Stabilized Temperature Platform Furnace (STPF) concept. STPF includes all of the following parameters (5.2.):
a. Integrated Absorbance,
b. Fast Instrument Electronics and Sampling Frequency,
c. Background Correction,
d. Maximum Power Heating,
e. Atomization off the L'vov platform in a pyrolytically coated graphite tube,
f. Gas Stop during Atomization,
g. Use of Matrix Modifiers.
1.7. Toxicology (5.14.)
Information listed within this section is synopsis of current knowledge of the physiological effects of cadmium and is not intended to be used as the basis for OSHA policy. IARC classifies cadmium and certain of its compounds as Group 2A carcinogens (probably carcinogenic to humans). Cadmium fume is intensely irritating to the respiratory tract. Workplace exposure to cadmium can cause both chronic and acute effects. Acute effects include tracheobronchitis, pneumonitis, and pulmonary edema. Chronic effects include anemia, rhinitis/anosmia, pulmonary emphysema, proteinuria and lung cancer. The primary target organs for chronic disease are the kidneys (non-carcinogenic) and the lungs (carcinogenic).
2. Sampling
2.1. Apparatus
2.1.1. Filter cassette unit for air sampling: A 37-mm diameter mixed cellulose ester membrane filter with a pore size of 0.8-µm contained in a 37-mm polystyrene two- or three-piece cassette filter holder (part no. MAWP 037 A0, Millipore Corp., Bedford, MA). The filter is supported with a cellulose backup pad. The cassette is sealed prior to use with a shrinkable gel band.
2.1.2. A calibrated personal sampling pump whose flow is determined to an accuracy of ±5% at the recommended flow rate with the filter cassette unit in line.
2.2. Procedure
2.2.1. Attach the prepared cassette to the calibrated sampling pump (the backup pad should face the pump) using flexible tubing. Place the sampling device on the employee such that air is sampled from the breathing zone.
2.2.2. Collect air samples at a flow rate of 2.0 L/min. If the filter does not become overloaded, a full-shift (at least seven hours) sample is strongly recommended for TWA and Action Level TWA measurements with a maximum air volume of 960 L. If overloading occurs, collect consecutive air samples for shorter sampling periods to cover the full workshift.
2.2.3. Replace the end plugs into the filter cassettes immediately after sampling. Record the sampling conditions.
2.2.4. Securely wrap each sample filter cassette end-to-end with an OSHA Form 21 sample seal.
2.2.5. Submit at least one blank sample with each set of air samples. The blank sample should be handled the same as the other samples except that no air is drawn through it.
2.2.6. Ship the samples to the laboratory for analysis as soon as possible in a suitable container designed to prevent damage in transit.
3. Analysis
3.1. Safety Precautions
3.1.1. Wear safety glasses, protective clothing and gloves at all times.
3.1.2. Handle acid solutions with care. Handle all cadmium samples and solutions with extra care (see Sect. 1.7.). Avoid their direct contact with work area surfaces, eyes, skin and clothes. Flush acid solutions which contact the skin or eyes with copious amounts of water.
3.1.3. Perform all acid digestions and acid dilutions in an exhaust hood while wearing a face shield. To avoid exposure to acid vapors, do not remove beakers containing concentrated acid solutions from the exhaust hood until they have returned to room temperature and have been diluted or emptied.
3.1.4. Exercise care when using laboratory glassware. Do not use chipped pipets, volumetric flasks, beakers or any glassware with sharp edges exposed in order to avoid the possibility of cuts or abrasions.
3.1.5. Never pipet by mouth.
3.1.6. Refer to the instrument instruction manuals and SOPs (5.8., 5.9.) for proper and safe operation of the atomic absorption spectrophotometer, graphite furnace atomizer and associated equipment.
3.1.7. Because metallic elements and other toxic substances are vaporized during AAS flame or graphite furnace atomizer operation, it is imperative that an exhaust vent be used. Always ensure that the exhaust system is operating properly during instrument use.
3.2. Apparatus for Sample and Standard Preparation
3.2.1. Hot plate, capable of reaching 150 °C, installed in an exhaust hood.
3.2.2. Phillips beakers, 125 mL.
3.2.3. Bottles, narrow-mouth, polyethylene or glass with leakproof caps: used for storage of standards and matrix modifier.
3.2.4. Volumetric flasks, volumetric pipets, beakers and other associated general laboratory glassware.
3.2.5. Forceps and other associated general laboratory equipment.
3.3. Apparatus for Flame AAS Analysis
3.3.1. Atomic absorption spectrophotometer consisting of a(an):
Nebulizer and burner head
Pressure regulating devices capable of maintaining constant oxidant and fuel pressures
Optical system capable of isolating the desired wavelength of radiation (228.8 nm)
Adjustable slit
Light measuring and amplifying device
Display, strip chart, or computer interface for indicating the amount of absorbed radiation
Cadmium hollow cathode lamp or electrodeless discharge lamp (EDL) and power supply
3.3.2. Oxidant: compressed air, filtered to remove water, oil and other foreign substances.
3.3.3. Fuel: standard commercially available tanks of acetylene dissolved in acetone; tanks should be equipped with flash arresters.
Caution: Do not use grades of acetylene containing solvents other than acetone because they may damage the PVC tubing used in some instruments.
3.3.4. Pressure-reducing valves: two gauge, two-stage pressure regulators to maintain fuel and oxidant pressures somewhat higher than the controlled operating pressures of the instrument.
3.3.5. Exhaust vent installed directly above the spectrophotometer burner head.
3.4. Apparatus for AAS-HGA Analysis
3.4.1. Atomic absorption spectrophotometer consisting of a(an):
Heated graphite furnace atomizer (HGA) with argon purge system
Pressure-regulating devices capable of maintaining constant argon purge pressure
Optical system capable of isolating the desired wavelength of radiation (228.8 nm)
Adjustable slit
Light measuring and amplifying device
Display, strip chart, or computer interface for indicating the amount of absorbed radiation (as integrated absorbance, peak area)
Background corrector: Zeeman or deuterium arc. The Zeeman background corrector is recommended
Cadmium hollow cathode lamp or electrodeless discharge lamp (EDL) and power supply
Autosampler capable of accurately injecting 5 to 20 µL sample aliquots onto the L'vov Platform in a graphite tube
3.4.2. Pyrolytically coated graphite tubes containing solid, pyrolytic L'vov platforms.
3.4.3. Polyethylene sample cups, 2.0 to 2.5 mL, for use with the autosampler.
3.4.4. Inert purge gas for graphite furnace atomizer: compressed gas cylinder of purified argon.
3.4.5. Two gauge, two-stage pressure regulator for the argon gas cylinder.
3.4.6. Cooling water supply for graphite furnace atomizer.
3.4.7. Exhaust vent installed directly above the graphite furnace atomizer.
3.5. Reagents
All reagents should be ACS analytical reagent grade or better.
3.5.1. Deionized water with a specific conductance of less than 10 µS.
3.5.2. Concentrated nitric acid, HNO 3.
3.5.3. Concentrated hydrochloric acid, HCl.
3.5.4. Ammonium phosphate, monobasic, NH 4 H 2 PO 4.
3.5.5. Magnesium nitrate, Mg(NO 3 ) 2 · 6H 2 O.
3.5.6. Diluting solution (4% HNO 3, 0.4% HCl): Add 40 mL HNO 3 and 4 mL HCl carefully to approximately 500 mL deionized water and dilute to 1 L with deionized water.
3.5.7. Cadmium standard stock solution, 1,000 µg/mL: Use a commercially available certified 1,000 µg/mL cadmium standard or, alternatively, dissolve 1.0000 g of cadmium metal in a minimum volume of 1:1 HCl and dilute to 1 L with 4% HNO 3. Observe expiration dates of commercial standards. Properly dispose of commercial standards with no expiration dates or prepared standards one year after their receipt or preparation date.
3.5.8. Matrix modifier for AAS-HGA analysis: Dissolve 1.0 g NH 4 H 2 PO 4 and 0.15 g Mg(NO 3 ) 2 · 6H 2 O in approximately 200 mL deionized water. Add 1 mL HNO 3 and dilute to 500 mL with deionized water.
3.5.9 Nitric Acid, 1:1 HNO 3 /DI H 2 O mixture: Carefully add a measured volume of concentrated HNO 3 to an equal volume of DI H 2 O.
3.5.10. Nitric acid, 10% v/v: Carefully add 100 mL of concentrated HNO 3 to 500 mL of DI H 2 O and dilute to 1 L.
3.6. Glassware Preparation
3.6.1. Clean Phillips beakers by refluxing with 1:1 nitric acid on a hot plate in a fume hood. Thoroughly rinse with deionized water and invert the beakers to allow them to drain dry.
3.6.2. Rinse volumetric flasks and all other glassware with 10% nitric acid and deionized water prior to use.
3.7. Standard Preparation for Flame AAS Analysis
3.7.1. Dilute stock solutions: Prepare 1, 5, 10 and 100 µg/mL cadmium standard stock solutions by making appropriate serial dilutions of 1,000 µg/mL cadmium standard stock solution with the diluting solution described in Section 3.5.6.
3.7.2. Working standards: Prepare cadmium working standards in the range of 0.02 to 2.0 µg/mL by making appropriate serial dilutions of the dilute stock solutions with the same diluting solution. A suggested method of preparation of the working standards is given below.
| Working standard | Std solution | Aliquot | Final vol. |
|---|---|---|---|
| (µg/mL) | (µg/mL) | (mL) | (mL) |
| 0.02 | 1 | 10 | 500 |
| 0.05 | 5 | 5 | 500 |
| 0.1 | 10 | 5 | 500 |
| 0.2 | 10 | 10 | 500 |
| 0.5 | 10 | 25 | 500 |
| 1 | 100 | 5 | 500 |
| 2 | 100 | 10 | 500 |
Store the working standards in 500-mL, narrow-mouth polyethylene or glass bottles with leak proof caps. Prepare every twelve months.
3.8. Standard Preparation for AAS-HGA Analysis
3.8.1. Dilute stock solutions: Prepare 10, 100 and 1,000 ng/mL cadmium standard stock solutions by making appropriate ten-fold serial dilutions of the 1,000 µg/mL cadmium standard stock solution with the diluting solution described in Section 3.5.6.
3.8.2. Working standards: Prepare cadmium working standards in the range of 0.2 to 20 ng/mL by making appropriate serial dilutions of the dilute stock solutions with the same diluting solution. A suggested method of preparation of the working standards is given below.
| Working standard | Std solution | Aliquot | Final vol. |
|---|---|---|---|
| (ng/mL) | (ng/mL) | (mL) | (mL) |
| 0.2 | 10 | 2 | 100 |
| 0.5 | 10 | 5 | 100 |
| 1 | 10 | 10 | 100 |
| 2 | 100 | 2 | 100 |
| 5 | 100 | 5 | 100 |
| 10 | 100 | 10 | 100 |
| 20 | 1,000 | 2 | 100 |
Store the working standards in narrow-mouth polyethylene or glass bottles with leakproof caps. Prepare monthly.
3.9. Sample Preparation
3.9.1. Carefully transfer each sample filter with forceps from its filter cassette unit to a clean, separate 125-mL Phillips beaker along with any loose dust found in the cassette. Label each Phillips beaker with the appropriate sample number.
3.9.2. Digest the sample by adding 5 mL of concentrated nitric acid (HNO 3 ) to each Phillips beaker containing an air filter sample. Place the Phillips beakers on a hot plate in an exhaust hood and heat the samples until approximately 0.5 mL remains. The sample solution in each Phillips beaker should become clear. If it is not clear, digest the sample with another portion of concentrated nitric acid.
3.9.3. After completing the HNO 3 digestion and cooling the samples, add 40 µL (2 drops) of concentrated HCl to each air sample solution and then swirl the contents. Carefully add about 5 mL of deionized water by pouring it down the inside of each beaker.
3.9.4. Quantitatively transfer each cooled air sample solution from each Phillips beaker to a clean 10-mL volumetric flask. Dilute each flask to volume with deionized water and mix well.
3.10. Flame AAS Analysis
Analyze all of the air samples for their cadmium content by flame atomic absorption spectroscopy (AAS) according to the instructions given below.
3.10.1. Set up the atomic absorption spectrophotometer for the air/acetylene flame analysis of cadmium according to the SOP (5.8.) or the manufacturer's operational instructions. For the source lamp, use the cadmium hollow cathode or electrodeless discharge lamp operated at the manufacturer's recommended rating for continuous operation. Allow the lamp to warm up 10 to 20 min or until the energy output stabilizes. Optimize conditions such as lamp position, burner head alignment, fuel and oxidant flow rates, etc. See the SOP or specific instrument manuals for details. Instrumental parameters for the Perkin-Elmer Model 603 used in the validation of this method are given in Attachment 1.
3.10.2. Aspirate and measure the absorbance of a standard solution of cadmium. The standard concentration should be within the linear range. For the instrumentation used in the validation of this method a 2 µg/mL cadmium standard gives a net absorbance reading of about 0.350 abs. units (see Section 1.5.5.) when the instrument and the source lamp are performing to manufacturer specifications.
3.10.3. To increase instrument response, scale expand the absorbance reading of the aspirated 2 µg/mL working standard approximately four times. Increase the integration time to at least 3 seconds to reduce signal noise.
3.10.4. Autozero the instrument while aspirating a deionized water blank. Monitor the variation in the baseline absorbance reading (baseline noise) for a few minutes to insure that the instrument, source lamp and associated equipment are in good operating condition.
3.10.5. Aspirate the working standards and samples directly into the flame and record their absorbance readings. Aspirate the deionized water blank immediately after every standard or sample to correct for and monitor any baseline drift and noise. Record the baseline absorbance reading of each deionized water blank. Label each standard and sample reading and its accompanying baseline reading.
3.10.6. It is recommended that the entire series of working standards be analyzed at the beginning and end of the analysis of a set of samples to establish a concentration-response curve, ensure that the standard readings agree with each other and are reproducible. Also, analyze a working standard after every five or six samples to monitor the performance of the spectrophotometer. Standard readings should agree within ±10 to 15% of the readings obtained at the beginning of the analysis.
3.10.7. Bracket the sample readings with standards during the analysis. If the absorbance reading of a sample is above the absorbance reading of the highest working standard, dilute the sample with diluting solution and reanalyze. Use the appropriate dilution factor in the calculations.
3.10.8. Repeat the analysis of approximately 10% of the samples for a check of precision.
3.10.9. If possible, analyze quality control samples from an independent source as a check on analytical recovery and precision.
3.10.10. Record the final instrument settings at the end of the analysis. Date and label the output.
3.11. AAS-HGA Analysis
Initially analyze all of the air samples for their cadmium content by flame atomic absorption spectroscopy (AAS) according to the instructions given in Section 3.10. If the concentration of cadmium in a sample solution is less than three times the quantitative detection limit [0.04 µg/mL (40 ng/mL) for the instrumentation used in the validation] and the sample results are to be averaged with other samples for TWA calculations, proceed with the AAS-HGA analysis of the sample as described below.
3.11.1. Set up the atomic absorption spectrophotometer and HGA for flameless atomic absorption analysis of cadmium according to the SOP (5.9.) or the manufacturer's operational instructions and allow the instrument to stabilize. The graphite furnace atomizer is equipped with a pyrolytically coated graphite tube containing a pyrolytic platform. For the source lamp, use a cadmium hollow cathode or electrodeless discharge lamp operated at the manufacturer's recommended setting for graphite furnace operation. The Zeeman background corrector and EDL are recommended for use with the L'vov platform. Instrumental parameters for the Perkin-Elmer Model 5100 spectrophotometer and Zeeman HGA-600 graphite furnace used in the validation of this method are given in Attachment 2.
3.11.2. Optimize the energy reading of the spectrophotometer at 228.8 nm by adjusting the lamp position and the wavelength according to the manufacturer's instructions.
3.11.3. Set up the autosampler to inject a 5-µL aliquot of the working standard, sample or reagent blank solution onto the L'vov platform along with a 10-µL overlay of the matrix modifier.
3.11.4. Analyze the reagent blank (diluting solution, Section 3.5.6.) and then autozero the instrument before starting the analysis of a set of samples. It is recommended that the reagent blank be analyzed several times during the analysis to assure the integrated absorbance (peak area) reading remains at or near zero.
3.11.5. Analyze a working standard approximately midway in the linear portion of the working standard range two or three times to check for reproducibility and sensitivity (see sections 1.5.5. and 1.5.6.) before starting the analysis of samples. Calculate the experimental characteristic mass value from the average integrated absorbance reading and injection volume of the analyzed working standard. Compare this value to the manufacturer's suggested value as a check of proper instrument operation.
3.11.6. Analyze the reagent blank, working standard, and sample solutions. Record and label the peak area (abs-sec) readings and the peak and background peak profiles on the printer/plotter.
3.11.7. It is recommended the entire series of working standards be analyzed at the beginning and end of the analysis of a set of samples. Establish a concentration-response curve and ensure standard readings agree with each other and are reproducible. Also, analyze a working standard after every five or six samples to monitor the performance of the system. Standard readings should agree within ±15% of the readings obtained at the beginning of the analysis.
3.11.8. Bracket the sample readings with standards during the analysis. If the peak area reading of a sample is above the peak area reading of the highest working standard, dilute the sample with the diluting solution and reanalyze. Use the appropriate dilution factor in the calculations.
3.11.9. Repeat the analysis of approximately 10% of the samples for a check of precision.
3.11.10. If possible, analyze quality control samples from an independent source as a check of analytical recovery and precision.
3.11.11. Record the final instrument settings at the end of the analysis. Date and label the output.
3.12. Calculations
3.12.1. Correct for baseline drift and noise in flame AAS analysis by subtracting each baseline absorbance reading from its corresponding working standard or sample absorbance reading to obtain the net absorbance reading for each standard and sample.
3.12.2. Use a least squares regression program to plot a concentration-response curve of net absorbance reading (or peak area for HGA analysis) versus concentration (µg/mL or ng/mL) of cadmium in each working standard.
3.12.3. Determine the concentration (µg/mL or ng/mL) of cadmium in each sample from the resulting concentration-response curve. If the concentration of cadmium in a sample solution is less than three times the quantitative detection limit [0.04 µg/mL (40 ng/mL) for the instrumentation used in the validation of the method] and if consecutive samples were taken on one employee and the sample results are to be averaged with other samples to determine a single TWA, reanalyze the sample by AAS-HGA as described in Section 3.11. and report the AAS-HGA analytical results.
3.12.4. Calculate the total amount (µg or ng) of cadmium in each sample from the sample solution volume (mL):
W = (C)(sample vol, mL)(DF)
Where:
W = Total cadmium in sample
C = Calculated concentration of cadmium
DF = Dilution Factor (if applicable)
3.12.5. Make a blank correction for each air sample by subtracting the total amount of cadmium in the corresponding blank sample from the total amount of cadmium in the sample.
3.12.6. Calculate the concentration of cadmium in an air sample (mg/m 3 or µg/m 3 ) by using one of the following equations:
3
bc
or
3
bc
Where:
bc
4. Backup Data
4.1. Introduction
4.1.1. The purpose of this evaluation is to determine the analytical method recovery, working standard range, and qualitative and quantitative detection limits of the two atomic absorption analytical techniques included in this method. The evaluation consisted of the following experiments:
1. An analysis of 24 samples (six samples each at 0.1, 0.5, 1 and 2 times the TWA-PEL) for the analytical method recovery study of the flame AAS analytical technique.
2. An analysis of 18 samples (six samples each at 0.5, 1 and 2 times the Action Level TWA-PEL) for the analytical method recovery study of the AAS-HGA analytical technique.
3. Multiple analyses of the reagent blank and a series of standard solutions to determine the working standard range and the qualitative and quantitative detection limits for both atomic absorption analytical techniques.
4.1.2. The analytical method recovery results at all test levels were calculated from concentration-response curves and statistically examined for outliers at the 99% confidence level. Possible outliers were determined using the Treatment of Outliers test (5.10.). In addition, the sample results of the two analytical techniques, at 0.5, 1.0 and 2.0 times their target concentrations, were tested for homogeneity of variances also at the 99% confidence level. Homogeneity of the coefficients of variation was determined using the Bartlett's test (5.11.). The overall analytical error (OAE) at the 95% confidence level was calculated using the equation (5.12.):
1
4.1.3. A derivation of the International Union of Pure and Applied Chemistry (IUPAC) detection limit equation (5.13.) was used to determine the qualitative and quantitative detection limits for both atomic absorption analytical techniques:
ld
Where:
ld
k = 3 for the Qualitative Detection Limit at the 99.86% Confidence Level
= 10 for the Quantitative Detection Limit at the 99.99% Confidence Level.
sd = standard deviation of the reagent blank (Rbl) readings.
m = analytical sensitivity or slope as calculated by linear regression.
4.1.4. Collection efficiencies of metallic fume and dust atmospheres on 0.8-µm mixed cellulose ester membrane filters are well documented and have been shown to be excellent (5.11.). Since elemental cadmium and the cadmium component of cadmium compounds are nonvolatile, stability studies of cadmium spiked MCEF samples were not performed.
4.2. Equipment
4.2.1. A Perkin-Elmer (PE) Model 603 spectrophotometer equipped with a manual gas control system, a stainless steel nebulizer, a burner mixing chamber, a flow spoiler and a 10 cm. (one-slot) burner head was used in the experimental validation of the flame AAS analytical technique. A PE cadmium hollow cathode lamp, operated at the manufacturer's recommended current setting for continuous operation (4 mA), was used as the source lamp. Instrument parameters are listed in Attachment 1.
4.2.2. A PE Model 5100 spectrophotometer, Zeeman HGA-600 graphite furnace atomizer and AS-60 HGA autosampler were used in the experimental validation of the AAS-HGA analytical technique. The spectrophotometer was equipped with a PE Series 7700 professional computer and Model PR-310 printer. A PE System 2 cadmium electrodeless discharge lamp, operated at the manufacturer's recommended current setting for modulated operation (170 mA), was used as the source lamp. Instrument parameters are listed in Attachment 2.
4.3. Reagents
4.3.1. J.T. Baker Chem. Co. (Analyzed grade) concentrated nitric acid, 69.0-71.0%, and concentrated hydrochloric acid, 36.5-38.0%, were used to prepare the samples and standards.
4.3.2. Ammonium phosphate, monobasic, NH 4 H 2 PO 4 and magnesium nitrate, Mg(NO 3 ) 2 6H 2 O, both manufactured by the Mallinckrodt Chem. Co., were used to prepare the matrix modifier for AAS-HGA analysis.
4.4. Standard Preparation for Flame AAS Analysis
4.4.1. Dilute stock solutions: Prepared 0.01, 0.1, 1, 10 and 100 µg/mL cadmium standard stock solutions by making appropriate serial dilutions of a commercially available 1,000 µg/mL cadmium standard stock solution (RICCA Chemical Co., Lot# A102) with the diluting solution (4% HNO 3, 0.4% HCl).
4.4.2. Analyzed Standards: Prepared cadmium standards in the range of 0.001 to 2.0 µg/mL by pipetting 2 to 10 mL of the appropriate dilute cadmium stock solution into a 100-mL volumetric flask and diluting to volume with the diluting solution. (See Section 3.7.2.)
4.5. Standard Preparation for AAS-HGA Analysis
4.5.1. Dilute stock solutions: Prepared 1, 10, 100 and 1,000 ng/mL cadmium standard stock solutions by making appropriate serial dilutions of a commercially available 1,000 µg/mL cadmium standard stock solution (J.T. Baker Chemical Co., Instra-analyzed, Lot# D22642) with the diluting solution (4% HNO 3, 0.4% HCl).
4.5.2. Analyzed Standards: Prepared cadmium standards in the range of 0.1 to 40 ng/mL by pipetting 2 to 10 mL of the appropriate dilute cadmium stock solution into a 100-mL volumetric flask and diluting to volume with the diluting solution. (See Section 3.8.2.)
4.6. Detection Limits and Standard Working Range for Flame AAS Analysis
4.6.1. Analyzed the reagent blank solution and the entire series of cadmium standards in the range of 0.001 to 2.0 µg/mL three to six times according to the instructions given in Section 3.10. The diluting solution (4% HNO 3, 0.4% HCl) was used as the reagent blank. The integration time on the PE 603 spectrophotometer was set to 3.0 seconds and a four-fold expansion of the absorbance reading of the 2.0 µg/mL cadmium standard was made prior to analysis. The 2.0 µg/mL standard gave a net absorbance reading of 0.350 abs. units prior to expansion in agreement with the manufacturer's specifications (5.6.).
4.6.2. The net absorbance readings of the reagent blank and the low concentration Cd standards from 0.001 to 0.1 µg/mL and the statistical analysis of the results are shown in Table I. The standard deviation, sd, of the six net absorbance readings of the reagent blank is 1.05 abs. units. The slope, m, as calculated by a linear regression plot of the net absorbance readings (shown in Table II) of the 0.02 to 1.0 µg/mL cadmium standards versus their concentration is 772.7 abs. units/(µg/mL).
4.6.3. If these values for sd and the slope, m, are used in Eqn. 1 (Sect. 4.1.3.), the qualitative and quantitative detection limits as determined by the IUPAC Method are:
ld
= 0.0041 µg/mL for the qualitative detection limit.
ld
= 0.014 µg/mL for the quantitative detection limit.
The qualitative and quantitative detection limits for the flame AAS analytical technique are 0.041 µg and 0.14 µg cadmium, respectively, for a 10 mL solution volume. These correspond, respectively, to 0.2 µg/m 3 and 0.70 µg/m 3 for a 200 L air volume.
4.6.4. The recommended Cd standard working range for flame AAS analysis is 0.02 to 2.0 µg/mL. The net absorbance readings of the reagent blank and the recommended working range standards and the statistical analysis of the results are shown in Table II. The standard of lowest concentration in the working range, 0.02 µg/mL, is slightly greater than the calculated quantitative detection limit, 0.014 µg/mL. The standard of highest concentration in the working range, 2.0 µg/mL, is at the upper end of the linear working range suggested by the manufacturer (5.6.). Although the standard net absorbance readings are not strictly linear at concentrations above 0.5 µg/mL, the deviation from linearity is only about 10% at the upper end of the recommended standard working range. The deviation from linearity is probably caused by the four-fold expansion of the signal suggested in the method. As shown in Table II, the precision of the standard net absorbance readings are excellent throughout the recommended working range; the relative standard deviations of the readings range from 0.009 to 0.064.
4.7. Detection Limits and Standard Working Range for AAS-HGA Analysis
4.7.1. Analyzed the reagent blank solution and the entire series of cadmium standards in the range of 0.1 to 40 ng/mL according to the instructions given in Section 3.11. The diluting solution (4% HNO 3, 0.4% HCl) was used as the reagent blank. A fresh aliquot of the reagent blank and of each standard was used for every analysis. The experimental characteristic mass value was 0.41 pg, calculated from the average peak area (abs-sec) reading of the 5 ng/mL standard which is approximately midway in the linear portion of the working standard range. This agreed within 20% with the characteristic mass value, 0.35 pg, listed by the manufacturer of the instrument (5.2.).
4.7.2. The peak area (abs-sec) readings of the reagent blank and the low concentration Cd standards from 0.1 to 2.0 ng/mL and statistical analysis of the results are shown in Table III. Five of the reagent blank peak area readings were zero and the sixth reading was 1 and was an outlier. The near lack of a blank signal does not satisfy a strict interpretation of the IUPAC method for determining the detection limits. Therefore, the standard deviation of the six peak area readings of the 0.2 ng/mL cadmium standard, 0.75 abs-sec, was used to calculate the detection limits by the IUPAC method. The slope, m, as calculated by a linear regression plot of the peak area (abs-sec) readings (shown in Table IV) of the 0.2 to 10 ng/mL cadmium standards versus their concentration is 51.5 abs-sec/(ng/mL).
4.7.3. If 0.75 abs-sec (sd) and 51.5 abs-sec/(ng/mL) (m) are used in Eqn. 1 (Sect. 4.1.3.), the qualitative and quantitative detection limits as determined by the IUPAC method are:
ld
= 0.044 ng/mL for the qualitative detection limit.
ld
The qualitative and quantitative detection limits for the AAS-HGA analytical technique are 0.44 ng and 1.5 ng cadmium, respectively, for a 10 mL solution volume. These correspond, respectively, to 0.007 µg/m 3 and 0.025 µg/m 3 for a 60 L air volume.
4.7.4. The peak area (abs-sec) readings of the Cd standards from 0.2 to 40 ng/mL and the statistical analysis of the results are given in Table IV. The recommended standard working range for AAS-HGA analysis is 0.2 to 20 ng/mL. The standard of lowest concentration in the recommended working range is slightly greater than the calculated quantitative detection limit, 0.15 ng/mL. The deviation from linearity of the peak area readings of the 20 ng/mL standard, the highest concentration standard in the recommended working range, is approximately 10%. The deviations from linearity of the peak area readings of the 30 and 40 ng/mL standards are significantly greater than 10%. As shown in Table IV, the precision of the peak area readings are satisfactory throughout the recommended working range; the relative standard deviations of the readings range from 0.025 to 0.083.
4.8. Analytical Method Recovery for Flame AAS Analysis
4.8.1. Four sets of spiked MCEF samples were prepared by injecting 20 µL of 10, 50, 100 and 200 µg/mL dilute cadmium stock solutions on 37 mm diameter filters (part no. AAWP 037 00, Millipore Corp., Bedford, MA) with a calibrated micropipet. The dilute stock solutions were prepared by making appropriate serial dilutions of a commercially available 1,000 µg/mL cadmium standard stock solution (RICCA Chemical Co., Lot# A102) with the diluting solution (4% HNO 3, 0.4% HCl). Each set contained six samples and a sample blank. The amount of cadmium in the prepared sets were equivalent to 0.1, 0.5, 1.0 and 2.0 times the TWA PEL target concentration of 5 µg/m 3 for a 400 L air volume.
4.8.2. The air-dried spiked filters were digested and analyzed for their cadmium content by flame atomic absorption spectroscopy (AAS) following the procedure described in Section 3. The 0.02 to 2.0µg/mL cadmium standards (the suggested working range) were used in the analysis of the spiked filters.
4.8.3. The results of the analysis are given in Table V. One result at 0.5 times the TWA PEL target concentration was an outlier and was excluded from statistical analysis. Experimental justification for rejecting it is that the outlier value was probably due to a spiking error. The coefficients of variation for the three test levels at 0.5 to 2.0 times the TWA PEL target concentration passed the Bartlett's test and were pooled.
4.8.4. The average recovery of the six spiked filter samples at 0.1 times the TWA PEL target concentration was 118.2% with a coefficient of variation (CV 1 ) of 0.128. The average recovery of the spiked filter samples in the range of 0.5 to 2.0 times the TWA target concentration was 104.0% with a pooled coefficient of variation (CV 1 ) of 0.010. Consequently, the analytical bias found in these spiked sample results over the tested concentration range was + 4.0% and the OAE was ±6.0%.
4.9. Analytical Method Recovery for AAS-HGA Analysis
4.9.1. Three sets of spiked MCEF samples were prepared by injecting 15µL of 5, 10 and 20 µg/mL dilute cadmium stock solutions on 37 mm diameter filters (part no. AAWP 037 00, Millipore Corp., Bedford, MA) with a calibrated micropipet. The dilute stock solutions were prepared by making appropriate serial dilutions of a commercially available certified 1,000 µg/mL cadmium standard stock solution (Fisher Chemical Co., Lot# 913438-24) with the diluting solution (4% HNO 3, 0.4% HCl). Each set contained six samples and a sample blank. The amount of cadmium in the prepared sets were equivalent to 0.5, 1 and 2 times the Action Level TWA target concentration of 2.5 µg/m 3 for a 60 L air volume.
4.9.2. The air-dried spiked filters were digested and analyzed for their cadmium content by flameless atomic absorption spectroscopy using a heated graphite furnace atomizer following the procedure described in Section 3. A five-fold dilution of the spiked filter samples at 2 times the Action Level TWA was made prior to their analysis. The 0.05 to 20 ng/mL cadmium standards were used in the analysis of the spiked filters.
4.9.3. The results of the analysis are given in Table VI. There were no outliers. The coefficients of variation for the three test levels at 0.5 to 2.0 times the Action Level TWA PEL passed the Bartlett's test and were pooled. The average recovery of the spiked filter samples was 94.2% with a pooled coefficient of variation (CV 1 ) of 0.043. Consequently, the analytical bias was −5.8% and the OAE was ±14.2%.
4.10. Conclusions
The experiments performed in this evaluation show the two atomic absorption analytical techniques included in this method to be precise and accurate and have sufficient sensitivity to measure airborne cadmium over a broad range of exposure levels and sampling periods.
5. References
5.1. Slavin, W. Graphite Furnace AAS—A Source Book; Perkin-Elmer Corp., Spectroscopy Div.: Ridgefield, CT, 1984; p. 18 and pp. 83-90.
5.2. Grosser, Z., Ed.; Techniques in Graphite Furnace Atomic Absorption Spectrophotometry; Perkin-Elmer Corp., Spectroscopy Div.: Ridgefield, CT, 1985.
5.3. Occupational Safety and Health Administration Salt Lake Technical Center: Metal and Metalloid Particulate in Workplace Atmospheres (Atomic Absorption) (USDOL/OSHA Method No. ID-121). In OSHA Analytical Methods Manual 2nd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, 1991.
5.4. Occupational Safety and Health Administration Salt Lake Technical Center: Metal and Metalloid Particulate in Workplace Atmospheres (ICP) (USDOL/OSHA Method No. ID-125G). In OSHA Analytical Methods Manual 2nd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, 1991.
5.5. Windholz, M., Ed.; The Merck Index, 10th ed.; Merck & Co.: Rahway, NJ, 1983.
5.6. Analytical Methods for Atomic Absorption Spectrophotometry, The Perkin-Elmer Corporation: Norwalk, CT, 1982.
5.7. Slavin, W., D.C. Manning, G. Carnrick, and E. Pruszkowska: Properties of the Cadmium Determination with the Platform Furnace and Zeeman Background Correction. Spectrochim. Acta 38B:1157-1170 (1983).
5.8. Occupational Safety and Health Administration Salt Lake Technical Center: Standard Operating Procedure for Atomic Absorption. Salt Lake City, UT: USDOL/OSHA-SLTC, In progress.
5.9. Occupational Safety and Health Administration Salt Lake Technical Center: AAS-HGA Standard Operating Procedure. Salt Lake City, UT: USDOL/OSHA-SLTC, In progress.
5.10. Mandel, J.: Accuracy and Precision, Evaluation and Interpretation of Analytical Results, The Treatment of Outliers. In Treatise On Analytical Chemistry, 2nd ed., Vol.1, edited by I. M. Kolthoff and P. J. Elving. New York: John Wiley and Sons, 1978. pp. 282-285.
5.11. National Institute for Occupational Safety and Health: Documentation of the NIOSH Validation Tests by D. Taylor, R. Kupel, and J. Bryant (DHEW/NIOSH Pub. No. 77-185). Cincinnati, OH: National Institute for Occupational Safety and Health, 1977.
5.12. Occupational Safety and Health Administration Analytical Laboratory: Precision and Accuracy Data Protocol for Laboratory Validations. In OSHA Analytical Methods Manual 1st ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists (Pub. No. ISBN: 0-936712-66-X), 1985.
5.13. Long, G.L. and J.D. Winefordner: Limit of Detection—A Closer Look at the IUPAC Definition. Anal.Chem. 55:712A-724A (1983).
5.14. American Conference of Governmental Industrial Hygienists: Documentation of Threshold Limit Values and Biological Exposure Indices. 5th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, 1986.
| STD (µg/mL) | Absorbance reading at 228.8 nm | Statistical analysis |
|---|---|---|
| Reagent blank | 5 2 4 3 4 3 | n = 6. mean = 3.50. std dev = 1.05. CV = 0.30. |
| 0.001 | 6 6 2 4 6 6 | n = 6. mean = 5.00. std dev = 1.67. CV = 0.335. |
| 0.002 | 5 7 7 3 7 4 | n = 6. mean = 5.50. std dev = 1.76. CV = 0.320. |
| 0.005 | 7 7 8 8 8 6 | n = 6. mean = 7.33. std dev = 0.817. CV = 0.111. |
| 0.010 | 10 9 10 13 10 10 | n = 6. mean = 10.3. std dev = 1.37. CV = 0.133. |
| 0.020 | 20 23 20 22 20 20 | n = 6. mean = 20.8. std dev = 1.33. CV = 0.064. |
| 0.050 | 42 42 42 42 42 45 | n = 6. mean = 42.5. std dev = 1.22. CV = 0.029. |
| 0.10 | 84 80 83 | n = 3. mean = 82.3. std dev = 2.08. CV = 0.025. |
| STD (µg/mL) | Absorbance reading at 228.8 nm | Statistical analysis |
|---|---|---|
| Reagent blank | 5 2 4 3 4 3 | n = 6. mean = 3.50. std dev = 1.05. CV = 0.30. |
| 0.020 | 20 23 20 22 20 20 | n = 6. mean = 20.8. std dev = 1.33. CV = 0.064. |
| 0.050 | 42 42 42 42 42 45 | n = 6. mean = 42.5. std dev = 1.22. CV = 0.029. |
| 0.10 | 84 80 83 | n = 3. mean = 82.3. std dev = 2.08. CV = 0.025. |
| 0.20 | 161 161 158 | n = 3. mean = 160.0. std dev = 1.73. CV = 0.011. |
| 0.50 | 391 389 393 | n = 3. mean = 391.0. std dev = 2.00. CV = 0.005. |
| 1.00 | 760 748 752 | n = 3. mean = 753.3. std dev = 6.11. CV = 0.008. |
| 2.00 | 1416 1426 1401 | n = 3. mean = 1414.3. std dev = 12.6. CV = 0.009. |
| STD (ng/mL) | Peak area readings × 10 3 at 228.8 nm | Statistical analysis |
|---|---|---|
| Reagent blank | 0 0 0 1 0 0 | n = 6. mean = 0.167. std dev = 0.41. CV = 2.45. |
| 0.1 | 8 6 5 7 13 7 | n = 6. mean = 7.7. std dev = 2.8. CV = 0.366. |
| 0.2 | 11 13 11 12 12 12 | n = 6. mean = 11.8. std dev = 0.75. CV = 0.064. |
| 0.5 | 28 33 26 28 28 30 | n = 6. mean = 28.8. std dev = 2.4. CV = 0.083. |
| 1.0 | 52 55 56 58 54 54 | n = 6. mean = 54.8. std dev = 2.0. CV = 0.037. |
| 2.0 | 101 112 110 110 110 110 | n = 6. mean = 108.8. std dev = 3.9. CV = 0.036. |
| STD (ng/mL) | Peak area readings × 10 3 at 228.8 nm | Statistical analysis |
|---|---|---|
| 0.2 | 11 13 11 12 12 12 | n = 6. mean = 11.8. std dev = 0.75. CV = 0.064. |
| 0.5 | 28 33 26 28 28 30 | n = 6. mean = 28.8. std dev = 2.4. CV = 0.083. |
| 1.0 | 52 55 56 58 54 54 | n = 6. mean = 54.8. std dev = 2.0. CV = 0.037. |
| 2.0 | 101 112 110 110 110 110 | n = 6. mean = 108.8. std dev = 3.9. CV = 0.036. |
| 5.0 | 247 265 268 275 259 279 | n = 6. mean = 265.5. std dev = 11.5. CV = 0.044. |
| 10.0 | 495 520 523 513 516 533 | n = 6. mean = 516.7. std dev = 12.7. CV = 0.025. |
| 20.0 | 950 953 951 958 949 890 | n = 6. mean = 941.8. std dev = 25.6. CV = 0.027. |
| 30.0 | 1269 1291 1303 1307 1295 1290 | n = 6. mean = 1293. std dev = 13.3. CV = 0.010. |
| 40.0 | 1505 1567 1535 1567 1566 1572 | n = 6. mean = 1552. std dev = 26.6. CV = 0.017. |
| Test level | 0.5 × | Percent rec. | µg taken | 1.0 × | Percent rec. | µg taken | 2.0 × | Percent rec. |
|---|---|---|---|---|---|---|---|---|
| µg taken | µg found | µg found | µg found | |||||
| 1.00 | 1.0715 | 107.2 | 2.00 | 2.0688 | 103.4 | 4.00 | 4.1504 | 103.8 |
| 1.00 | 1.0842 | 108.4 | 2.00 | 2.0174 | 100.9 | 4.00 | 4.1108 | 102.8 |
| 1.00 | 1.0842 | 108.4 | 2.00 | 2.0431 | 102.2 | 4.00 | 4.0581 | 101.5 |
| 1.00 | *1.0081 | *100.8 | 2.00 | 2.0431 | 102.2 | 4.00 | 4.0844 | 102.1 |
| 1.00 | 1.0715 | 107.2 | 2.00 | 2.0174 | 100.9 | 4.00 | 4.1504 | 103.8 |
| 1.00 | 1.0842 | 108.4 | 2.00 | 2.0045 | 100.2 | 4.00 | 4.1899 | 104.7 |
| n= | 5 | 6 | 6 |
|---|---|---|---|
| mean = | 107.9 | 101.6 | 103.1 |
| std dev = | 0.657 | 1.174 | 1.199 |
| CV 1 = | 0.006 | 0.011 | 0.012 |
| CV 1 (pooled) = 0.010 | |||
| * Rejected as an outlier—this value did not pass the outlier T-test at the 99% confidence level. |
| Test level | 0.1 × | Percent rec. |
|---|---|---|
| µg taken | µg found | |
| 0.200 | 0.2509 | 125.5 |
| 0.200 | 0.2509 | 125.5 |
| 0.200 | 0.2761 | 138.1 |
| 0.200 | 0.2258 | 112.9 |
| 0.200 | 0.2258 | 112.9 |
| 0.200 | 0.1881 | 94.1 |
| n= | 6 |
|---|---|
| mean = | 118.2 |
| std dev = | 15.1 |
| CV 1 = | 0.128 |
| Test level | 0.5 × | Percent rec. | ng taken | 1.0 × | Percent rec. | ng taken | 2.0 × | Percent rec. |
|---|---|---|---|---|---|---|---|---|
| ng taken | ng found | ng found | ng found | |||||
| 75 | 71.23 | 95.0 | 150 | 138.00 | 92.0 | 300 | 258.43 | 86.1 |
| 75 | 71.47 | 95.3 | 150 | 138.29 | 92.2 | 300 | 258.46 | 86.2 |
| 75 | 70.02 | 93.4 | 150 | 136.30 | 90.9 | 300 | 280.55 | 93.5 |
| 75 | 77.34 | 103.1 | 150 | 146.62 | 97.7 | 300 | 288.34 | 96.1 |
| 75 | 78.32 | 104.4 | 150 | 145.17 | 96.8 | 300 | 261.74 | 87.2 |
| 75 | 71.96 | 95.9 | 150 | 144.88 | 96.6 | 300 | 277.22 | 92.4 |
| n= | 6 | 6 | 6 |
|---|---|---|---|
| mean = | 97.9 | 94.4 | 90.3 |
| std dev = | 4.66 | 2.98 | 4.30 |
| CV 1 = | 0.048 | 0.032 | 0.048 |
| CV 1 (pooled) = 0.043 |
Attachment 1
Instrumental Parameters for Flame AAS Analysis
Atomic Absorption Spectrophotometer (Perkin-Elmer Model 603)
Flame: Air/Acetylene—lean, blue
Oxidant Flow: 55
Fuel Flow: 32
Wavelength: 228.8 nm
Slit: 4 (0.7 nm)
Range: UV
Signal: Concentration (4 exp)
Integration Time: 3 sec
Attachment 2
Instrumental Parameters for HGA Analysis
Atomic Absorption Spectrophotometer (Perkin-Elmer Model 5100)
Signal Type: Zeeman AA
Slitwidth: 0.7 nm
Wavelength: 228.8 nm
Measurement: Peak Area
Integration Time: 6.0 sec
BOC Time: 5 sec
BOC = Background Offset Correction.
| Step | Ramp time (sec) | Hold time (sec) | Temp. (°C) | Argon flow (mL/min) | Read (sec) |
|---|---|---|---|---|---|
| 1) Predry | 5 | 10 | 90 | 300 | |
| 2) Dry | 30 | 10 | 140 | 300 | |
| 3) Char | 10 | 20 | 900 | 300 | |
| 4) Cool Down | 1 | 8 | 30 | 300 | |
| 5) Atomize | 0 | 5 | 1600 | 0 | −1 |
| 6) Burnout | 1 | 8 | 2500 | 300 |
Appendix F to § 1910.1027—Nonmandatory Protocol for Biological Monitoring
1.00 Introduction
Under the final OSHA cadmium rule (29 CFR part 1910), monitoring of biological specimens and several periodic medical examinations are required for eligible employees. These medical examinations are to be conducted regularly, and medical monitoring is to include the periodic analysis of cadmium in blood (CDB), cadmium in urine (CDU) and beta-2-microglobulin in urine (B2MU). As CDU and B2MU are to be normalized to the concentration of creatinine in urine (CRTU), then CRTU must be analyzed in conjunction with CDU and B2MU analyses.
The purpose of this protocol is to provide procedures for establishing and maintaining the quality of the results obtained from the analyses of CDB, CDU and B2MU by commercial laboratories. Laboratories conforming to the provisions of this nonmandatory protocol shall be known as “participating laboratories.” The biological monitoring data from these laboratories will be evaluated by physicians responsible for biological monitoring to determine the conditions under which employees may continue to work in locations exhibiting airborne-cadmium concentrations at or above defined actions levels (see paragraphs (l)(3) and (l)(4) of the final rule). These results also may be used to support a decision to remove workers from such locations.
Under the medical monitoring program for cadmium, blood and urine samples must be collected at defined intervals from workers by physicians responsible for medical monitoring; these samples are sent to commercial laboratories that perform the required analyses and report results of these analyses to the responsible physicians. To ensure the accuracy and reliability of these laboratory analyses, the laboratories to which samples are submitted should participate in an ongoing and efficacious proficiency testing program. Availability of proficiency testing programs may vary with the analyses performed.
To test proficiency in the analysis of CDB, CDU and B2MU, a laboratory should participate either in the interlaboratory comparison program operated by the Centre de Toxicologie du Quebec (CTQ) or an equivalent program. (Currently, no laboratory in the U.S. performs proficiency testing on CDB, CDU or B2MU.) Under this program, CTQ sends participating laboratories 18 samples of each analyte (CDB, CDU and/or B2MU) annually for analysis. Participating laboratories must return the results of these analyses to CTQ within four to five weeks after receiving the samples.
The CTQ program pools analytical results from many participating laboratories to derive consensus mean values for each of the samples distributed. Results reported by each laboratory then are compared against these consensus means for the analyzed samples to determine the relative performance of each laboratory. The proficiency of a participating laboratory is a function of the extent of agreement between results submitted by the participating laboratory and the consensus values for the set of samples analyzed.
Proficiency testing for CRTU analysis (which should be performed with CDU and B2MU analyses to evaluate the results properly) also is recommended. In the U.S., only the College of American Pathologists (CAP) currently conducts CRTU proficiency testing; participating laboratories should be accredited for CRTU analysis by the CAP.
Results of the proficiency evaluations will be forwarded to the participating laboratory by the proficiency-testing laboratory, as well as to physicians designated by the participating laboratory to receive this information. In addition, the participating laboratory should, on request, submit the results of their internal Quality Assurance/Quality Control (QA/QC) program for each analytic procedure ( i.e., CDB, CDU and/or B2MU) to physicians designated to receive the proficiency results. For participating laboratories offering CDU and/or B2MU analyses, QA/QC documentation also should be provided for CRTU analysis. (Laboratories should provide QA/QC information regarding CRTU analysis directly to the requesting physician if they perform the analysis in-house; if CRTU analysis is performed by another laboratory under contract, this information should be provided to the physician by the contract laboratory.)
QA/QC information, along with the actual biological specimen measurements, should be provided to the responsible physician using standard formats. These physicians then may collate the QA/QC information with proficiency test results to compare the relative performance of laboratories, as well as to facilitate evaluation of the worker monitoring data. This information supports decisions made by the physician with regard to the biological monitoring program, and for mandating medical removal.
This protocol describes procedures that may be used by the responsible physicians to identify laboratories most likely to be proficient in the analysis of samples used in the biological monitoring of cadmium; also provided are procedures for record keeping and reporting by laboratories participating in proficiency testing programs, and recommendations to assist these physicians in interpreting analytical results determined by participating laboratories. As the collection and handling of samples affects the quality of the data, recommendations are made for these tasks. Specifications for analytical methods to be used in the medical monitoring program are included in this protocol as well.
In conclusion, this document is intended as a supplement to characterize and maintain the quality of medical monitoring data collected under the final cadmium rule promulgated by OSHA (29 CFR part 1910). OSHA has been granted authority under the Occupational Safety and Health Act of 1970 to protect workers from the effects of exposure to hazardous substances in the work place and to mandate adequate monitoring of workers to determine when adverse health effects may be occurring. This nonmandatory protocol is intended to provide guidelines and recommendations to improve the accuracy and reliability of the procedures used to analyze the biological samples collected as part of the medical monitoring program for cadmium.
2.0 Definitions
When the terms below appear in this protocol, use the following definitions.
Accuracy: A measure of the bias of a data set. Bias is a systematic error that is either inherent in a method or caused by some artifact or idiosyncracy of the measurement system. Bias is characterized by a consistent deviation (positive or negative) in the results from an accepted reference value.
Arithmetic Mean: The sum of measurements in a set divided by the number of measurements in a set.
Blind Samples: A quality control procedure in which the concentration of analyte in the samples should be unknown to the analyst at the time that the analysis is performed.
Coefficient of Variation: The ratio of the standard deviation of a set of measurements to the mean (arithmetic or geometric) of the measurements.
Compliance Samples: Samples from exposed workers sent to a participating laboratory for analysis.
Control Charts: Graphic representations of the results for quality control samples being analyzed by a participating laboratory.
Control Limits: Statistical limits which define when an analytic procedure exceeds acceptable parameters; control limits provide a method of assessing the accuracy of analysts, laboratories, and discrete analytic runs.
Control Samples: Quality control samples.
F/T: The measured amount of an analyte divided by the theoretical value (defined below) for that analyte in the sample analyzed; this ratio is a measure of the recovery for a quality control sample.
Geometric Mean: The natural antilog of the mean of a set of natural log-transformed data.
Geometric Standard Deviation: The antilog of the standard deviation of a set of natural log-transformed data.
Limit of Detection: Using a predefined level of confidence, this is the lowest measured value at which some of the measured material is likely to have come from the sample.
Mean: A central tendency of a set of data; in this protocol, this mean is defined as the arithmetic mean (see definition of arithmetic mean above) unless stated otherwise.
Performance: A measure of the overall quality of data reported by a laboratory.
Pools: Groups of quality-control samples to be established for each target value (defined below) of an analyte. For the protocol provided in attachment 3, for example, the theoretical value of the quality control samples of the pool must be within a range defined as plus or minus (±) 50% of the target value. Within each analyte pool, there must be quality control samples of at least 4 theoretical values.
Precision: The extent of agreement between repeated, independent measurements of the same quantity of an analyte.
Proficiency: The ability to satisfy a specified level of analyte performance.
Proficiency Samples: Specimens, the values of which are unknown to anyone at a participating laboratory, and which are submitted by a participating laboratory for proficiency testing.
Quality or Data Quality: A measure of the confidence in the measurement value.
Quality Control (QC) Samples: Specimens, the value of which is unknown to the analyst, but is known to the appropriate QA/QC personnel of a participating laboratory; when used as part of a laboratory QA/QC program, the theoretical values of these samples should not be known to the analyst until the analyses are complete. QC samples are to be run in sets consisting of one QC sample from each pool (see definition of “pools” above).
Sensitivity: For the purposes of this protocol, the limit of detection.
Standard Deviation: A measure of the distribution or spread of a data set about the mean; the standard deviation is equal to the positive square root of the variance, and is expressed in the same units as the original measurements in the data set.
Standards: Samples with values known by the analyst and used to calibrate equipment and to check calibration throughout an analytic run. In a laboratory QA/QC program, the values of the standards must exceed the values obtained for compliance samples such that the lowest standard value is near the limit of detection and the highest standard is higher than the highest compliance sample or QC sample. Standards of at least three different values are to be used for calibration, and should be constructed from at least 2 different sources.
Target Value: Those values of CDB, CDU or B2MU which trigger some action as prescribed in the medical surveillance section of the regulatory text of the final cadmium rule. For CDB, the target values are 5, 10 and 15 µg/l. For CDU, the target values are 3, 7, and 15 µg/g CRTU. For B 2 MU, the target values are 300, 750 and 1500 µg/g CRTU. (Note that target values may vary as a function of time.)
Theoretical Value (or Theoretical Amount): The reported concentration of a quality-control sample (or calibration standard) derived from prior characterizations of the sample.
Value or Measurement Value: The numerical result of a measurement.
Variance: A measure of the distribution or spread of a data set about the mean; the variance is the sum of the squares of the differences between the mean and each discrete measurement divided by one less than the number of measurements in the data set.
3.0 Protocol
This protocol provides procedures for characterizing and maintaining the quality of analytic results derived for the medical monitoring program mandated for workers under the final cadmium rule.
3.1 Overview
The goal of this protocol is to assure that medical monitoring data are of sufficient quality to facilitate proper interpretation. The data quality objectives (DQOs) defined for the medical monitoring program are summarized in Table 1. Based on available information, the DQOs presented in Table 1 should be achievable by the majority of laboratories offering the required analyses commercially; OSHA recommends that only laboratories meeting these DQOs be used for the analysis of biological samples collected for monitoring cadmium exposure.
| Analyte/concentration pool | Limit of detection | Precision (CV) (%) | Accuracy |
|---|---|---|---|
| Cadmium in blood | 0.5 µg/l | ±1 µg/l or 15% of the mean. | |
| ≤2 µg/l | 40 | ||
| >2µg/l | 20 | ||
| Cadmium in urine | 0.5 µg/g creatinine | ±1 µg/l or 15% of the mean. | |
| ≤2 µg/l creatinine | 40 | ||
| >2µg/l creatinine | 20 | ||
| β-2-microglobulin in urine: 100 µg/g creatine | 100 µg/g creatinine | 5 | ±15% of the mean. |
To satisfy the DQOs presented in Table 1, OSHA provides the following guidelines:
1. Procedures for the collection and handling of blood and urine are specified (Section 3.4.1 of this protocol);
2. Preferred analytic methods for the analysis of CDB, CDU and B2MU are defined (and a method for the determination of CRTU also is specified since CDU and B2MU results are to be normalized to the level of CRTU).
3. Procedures are described for identifying laboratories likely to provide the required analyses in an accurate and reliable manner;
4. These guidelines (Sections 3.2.1 to 3.2.3, and Section 3.3) include recommendations regarding internal QA/QC programs for participating laboratories, as well as levels of proficiency through participation in an interlaboratory proficiency program;
5. Procedures for QA/QC record keeping (Section 3.3.2), and for reporting QC/QA results are described (Section 3.3.3); and,
6. Procedures for interpreting medical monitoring results are specified (Section 3.4.3).
Methods recommended for the biological monitoring of eligible workers are:
1. The method of Stoeppler and Brandt (1980) for CDB determinations (limit of detection: 0.5 µg/l);
2. The method of Pruszkowska et al. (1983) for CDU determinations (limit of detection: 0.5 µg/l of urine); and,
3. The Pharmacia Delphia test kit (Pharmacia 1990) for the determination of B2MU (limit of detection: 100 µg/l urine).
Because both CDU and B2MU should be reported in µg/g CRTU, an independent determination of CRTU is recommended. Thus, both the OSHA Salt Lake City Technical Center (OSLTC) method (OSHA, no date) and the Jaffe method (Du Pont, no date) for the determination of CRTU are specified under this protocol ( i.e., either of these 2 methods may be used). Note that although detection limits are not reported for either of these CRTU methods, the range of measurements expected for CRTU (0.9-1.7 µg/l) are well above the likely limit of detection for either of these methods (Harrison, 1987).
Laboratories using alternate methods should submit sufficient data to the responsible physicians demonstrating that the alternate method is capable of satisfying the defined data quality objectives of the program. Such laboratories also should submit a QA/QC plan that documents the performance of the alternate method in a manner entirely equivalent to the QA/QC plans proposed in Section 3.3.1.
3.2 Duties of the Responsible Physician
The responsible physician will evaluate biological monitoring results provided by participating laboratories to determine whether such laboratories are proficient and have satisfied the QA/QC recommendations. In determining which laboratories to employ for this purpose, these physicians should review proficiency and QA/QC data submitted to them by the participating laboratories.
Participating laboratories should demonstrate proficiency for each analyte (CDU, CDB and B2MU) sampled under the biological monitoring program. Participating laboratories involved in analyzing CDU and B2MU also should demonstrate proficiency for CRTU analysis, or provide evidence of a contract with a laboratory proficient in CRTU analysis.
3.2.1 Recommendations for Selecting Among Existing Laboratories
OSHA recommends that existing laboratories providing commercial analyses for CDB, CDU and/or B2MU for the medical monitoring program satisfy the following criteria:
1. Should have performed commercial analyses for the appropriate analyte (CDB, CDU and/or B2MU) on a regular basis over the last 2 years;
2. Should provide the responsible physician with an internal QA/QC plan;
3. If performing CDU or B2MU analyses, the participating laboratory should be accredited by the CAP for CRTU analysis, and should be enrolled in the corresponding CAP survey (note that alternate credentials may be acceptable, but acceptability is to be determined by the responsible physician); and,
4. Should have enrolled in the CTQ interlaboratory comparison program for the appropriate analyte (CDB, CDU and/or B2MU).
Participating laboratories should submit appropriate documentation demonstrating compliance with the above criteria to the responsible physician. To demonstrate compliance with the first of the above criteria, participating laboratories should submit the following documentation for each analyte they plan to analyze (note that each document should cover a period of at least 8 consecutive quarters, and that the period designated by the term “regular analyses” is at least once a quarter):
1. Copies of laboratory reports providing results from regular analyses of the appropriate analyte (CDB, CDU and/or B2MU);
2. Copies of 1 or more signed and executed contracts for the provision of regular analyses of the appropriate analyte (CDB, CDU and/or B2MU); or,
3. Copies of invoices sent to 1 or more clients requesting payment for the provision of regular analyses of the appropriate analyte (CDB, CDU and/or B2MU). Whatever the form of documentation submitted, the specific analytic procedures conducted should be identified directly. The forms that are copied for submission to the responsible physician also should identify the laboratory which provided these analyses.
To demonstrate compliance with the second of the above criteria, a laboratory should submit to the responsible physician an internal QA/QC plan detailing the standard operating procedures to be adopted for satisfying the recommended QA/QC procedures for the analysis of each specific analyte (CDB, CDU and/or B2MU). Procedures for internal QA/QC programs are detailed in Section 3.3.1 below.
To satisfy the third of the above criteria, laboratories analyzing for CDU or B2MU also should submit a QA/QC plan for creatinine analysis (CRTU); the QA/QC plan and characterization analyses for CRTU must come from the laboratory performing the CRTU analysis, even if the CRTU analysis is being performed by a contract laboratory.
Laboratories enrolling in the CTQ program (to satisfy the last of the above criteria) must remit, with the enrollment application, an initial fee of approximately $100 per analyte. (Note that this fee is only an estimate, and is subject to revision without notice.) Laboratories should indicate on the application that they agree to have proficiency test results sent by the CTQ directly to the physicians designated by participating laboratories.
Once a laboratory's application is processed by the CTQ, the laboratory will be assigned a code number which will be provided to the laboratory on the initial confirmation form, along with identification of the specific analytes for which the laboratory is participating. Confirmation of participation will be sent by the CTQ to physicians designated by the applicant laboratory.
3.2.2 Recommended Review of Laboratories Selected To Perform Analyses
Six months after being selected initially to perform analyte determinations, the status of participating laboratories should be reviewed by the responsible physicians. Such reviews should then be repeated every 6 months or whenever additional proficiency or QA/QC documentation is received (whichever occurs first).
As soon as the responsible physician has received the CTQ results from the first 3 rounds of proficiency testing ( i.e., 3 sets of 3 samples each for CDB, CDU and/or B2MU) for a participating laboratory, the status of the laboratory's continued participation should be reviewed. Over the same initial 6-month period, participating laboratories also should provide responsible physicians the results of their internal QA/QC monitoring program used to assess performance for each analyte (CDB, CDU and/or B2MU) for which the laboratory performs determinations. This information should be submitted using appropriate forms and documentation.
The status of each participating laboratory should be determined for each analyte ( i.e., whether the laboratory satisfies minimum proficiency guidelines based on the proficiency samples sent by the CTQ and the results of the laboratory's internal QA/QC program). To maintain competency for analysis of CDB, CDU and/or B2MU during the first review, the laboratory should satisfy performance requirements for at least 2 of the 3 proficiency samples provided in each of the 3 rounds completed over the 6-month period. Proficiency should be maintained for the analyte(s) for which the laboratory conducts determinations.
To continue participation for CDU and/or B2MU analyse, laboratories also should either maintain accreditation for CRTU analysis in the CAP program and participate in the CAP surveys, or they should contract the CDU and B2MU analyses to a laboratory which satisfies these requirements (or which can provide documentation of accreditation/participation in an equivalent program).
The performance requirement for CDB analysis is defined as an analytical result within ±1 µg/l blood or 15% of the consensus mean (whichever is greater). For samples exhibiting a consensus mean less than 1 µg/l, the performance requirement is defined as a concentration between the detection limit of the analysis and a maximum of 2 µg/l. The purpose for redefining the acceptable interval for low CDB values is to encourage proper reporting of the actual values obtained during measurement; laboratories, therefore, will not be penalized (in terms of a narrow range of acceptability) for reporting measured concentrations smaller than 1 µg/l.
The performance requirement for CDU analysis is defined as an analytical result within ±1 µg/l urine or 15% of the consensus mean (whichever is greater). For samples exhibiting a consensus mean less than 1 µg/l urine, the performance requirement is defined as a concentration between the detection limit of the analysis and a maximum of 2 µg/l urine. Laboratories also should demonstrate proficiency in creatinine analysis as defined by the CAP. Note that reporting CDU results, other than for the CTQ proficiency samples ( i.e., compliance samples), should be accompanied with results of analyses for CRTU, and these 2 sets of results should be combined to provide a measure of CDU in units of µg/g CRTU.
The performance requirement for B2MU is defined as analytical results within ±15% of the consensus mean. Note that reporting B2MU results, other than for CTQ proficiency samples ( i.e., compliance samples), should be accompanied with results of analyses for CRTU, and these 2 sets of results should be combined to provide a measure of B2MU in units of µg/g CRTU.
There are no recommended performance checks for CRTU analyses. As stated previously, laboratories performing CRTU analysis in support of CDU or B2MU analyses should be accredited by the CAP, and participating in the CAP's survey for CRTU.
Following the first review, the status of each participating laboratory should be reevaluated at regular intervals ( i.e., corresponding to receipt of results from each succeeding round of proficiency testing and submission of reports from a participating laboratory's internal QA/QC program).
After a year of collecting proficiency test results, the following proficiency criterion should be added to the set of criteria used to determine the participating laboratory's status (for analyzing CDB, CDU and/or B2MU): A participating laboratory should not fail performance requirements for more than 4 samples from the 6 most recent consecutive rounds used to assess proficiency for CDB, CDU and/or B2MU separately ( i.e., a total of 18 discrete proficiency samples for each analyte). Note that this requirement does not replace, but supplements, the recommendation that a laboratory should satisfy the performance criteria for at least 2 of the 3 samples tested for each round of the program.
3.2.3 Recommendations for Selecting Among Newly-Formed Laboratories (or Laboratories That Previously Failed To Meet the Protocol Guidelines)
OSHA recommends that laboratories that have not previously provided commercial analyses of CDB, CDU and/or B2MU (or have done so for a period less than 2 years), or which have provided these analyses for 2 or more years but have not conformed previously with these protocol guidelines, should satisfy the following provisions for each analyte for which determinations are to be made prior to being selected to analyze biological samples under the medical monitoring program:
1. Submit to the responsible physician an internal QA/QC plan detailing the standard operating procedures to be adopted for satisfying the QA/QC guidelines (guidelines for internal QA/QC programs are detailed in Section 3.3.1);
2. Submit to the responsible physician the results of the initial characterization analyses for each analyte for which determinations are to be made;
3. Submit to the responsible physician the results, for the initial 6-month period, of the internal QA/QC program for each analyte for which determinations are to be made (if no commercial analyses have been conducted previously, a minimum of 2 mock standardization trials for each analyte should be completed per month for a 6-month period);
4. Enroll in the CTQ program for the appropriate analyte for which determinations are to be made, and arrange to have the CTQ program submit the initial confirmation of participation and proficiency test results directly to the designated physicians. Note that the designated physician should receive results from 3 completed rounds from the CTQ program before approving a laboratory for participation in the biological monitoring program;
5. Laboratories seeking participation for CDU and/or B2MU analyses should submit to the responsible physician documentation of accreditation by the CAP for CRTU analyses performed in conjunction with CDU and/or B2MU determinations (if CRTU analyses are conducted by a contract laboratory, this laboratory should submit proof of CAP accreditation to the responsible physician); and,
6. Documentation should be submitted on an appropriate form.
To participate in CDB, CDU and/or B2MU analyses, the laboratory should satisfy the above criteria for a minimum of 2 of the 3 proficiency samples provided in each of the 3 rounds of the CTQ program over a 6-month period; this procedure should be completed for each appropriate analyte. Proficiency should be maintained for each analyte to continue participation. Note that laboratories seeking participation for CDU or B2MU also should address the performance requirements for CRTU, which involves providing evidence of accreditation by the CAP and participation in the CAP surveys (or an equivalent program).
The performance requirement for CDB analysis is defined as an analytical result within ±1 µg/l or 15% of the consensus mean (whichever is greater). For samples exhibiting a consensus mean less than 1 µg/l, the performance requirement is defined as a concentration between the detection limit of the analysis and a maximum of 2 µg/l. The purpose of redefining the acceptable interval for low CDB values is to encourage proper reporting of the actual values obtained during measurement; laboratories, therefore, will not be penalized (in terms of a narrow range of acceptability) for reporting measured concentrations less than 1 µg/l.
The performance requirement for CDU analysis is defined as an analytical result within ±1 µg/l urine or 15% of the consensus mean (whichever is greater). For samples exhibiting a consensus mean less than 1 µg/l urine, the performance requirement is defined as a concentration that falls between the detection limit of the analysis and a maximum of 2 µg/l urine. Performance requirements for the companion CRTU analysis (defined by the CAP) also should be met. Note that reporting CDU results, other than for CTQ proficiency testing should be accompanied with results of CRTU analyses, and these 2 sets of results should be combined to provide a measure of CDU in units of µg/g CRTU.
The performance requirement for B2MU is defined as an analytical result within ±15% of the consensus mean. Note that reporting B2MU results, other than for CTQ proficiency testing should be accompanied with results of CRTU analysis, these 2 sets of results should be combined to provide a measure of B2MU in units of µg/g CRTU.
Once a new laboratory has been approved by the responsible physician for conducting analyte determinations, the status of this approval should be reviewed periodically by the responsible physician as per the criteria presented under Section 3.2.2.
Laboratories which have failed previously to gain approval of the responsible physician for conducting determinations of 1 or more analytes due to lack of compliance with the criteria defined above for existing laboratories (Section 3.2.1), may obtain approval by satisfying the criteria for newly-formed laboratories defined under this section; for these laboratories, the second of the above criteria may be satisfied by submitting a new set of characterization analyses for each analyte for which determinations are to be made.
Reevaluation of these laboratories is discretionary on the part of the responsible physician. Reevaluation, which normally takes about 6 months, may be expedited if the laboratory can achieve 100% compliance with the proficiency test criteria using the 6 samples of each analyte submitted to the CTQ program during the first 2 rounds of proficiency testing.
For laboratories seeking reevaluation for CDU or B2MU analysis, the guidelines for CRTU analyses also should be satisfied, including accreditation for CRTU analysis by the CAP, and participation in the CAP survey program (or accreditation/participation in an equivalent program).
3.2.4 Future Modifications to the Protocol Guidelines
As participating laboratories gain experience with analyses for CDB, CDU and B2MU, it is anticipated that the performance achievable by the majority of laboratories should improve until it approaches that reported by the research groups which developed each method. OSHA, therefore, may choose to recommend stricter performance guidelines in the future as the overall performance of participating laboratories improves.
3.3 Guidelines for Record Keeping and Reporting
To comply with these guidelines, participating laboratories should satisfy the above-stated performance and proficiency recommendations, as well as the following internal QA/QC, record keeping, and reporting provisions.
If a participating laboratory fails to meet the provisions of these guidelines, it is recommended that the responsible physician disapprove further analyses of biological samples by that laboratory until it demonstrates compliance with these guidelines. On disapproval, biological samples should be sent to a laboratory that can demonstrate compliance with these guidelines, at least until the former laboratory is reevaluated by the responsible physician and found to be in compliance.
The following record keeping and reporting procedures should be practiced by participating laboratories.
3.3.1 Internal Quality Assurance/Quality Control Procedures
Laboratories participating in the cadmium monitoring program should develop and maintain an internal quality assurance/quality control (QA/QC) program that incorporates procedures for establishing and maintaining control for each of the analytic procedures (determinations of CDB, CDU and/or B2MU) for which the laboratory is seeking participation. For laboratories analyzing CDU and/or B2MU, a QA/QC program for CRTU also should be established.
Written documentation of QA/QC procedures should be described in a formal QA/QC plan; this plan should contain the following information: Sample acceptance and handling procedures ( i.e., chain-of-custody); sample preparation procedures; instrument parameters; calibration procedures; and, calculations. Documentation of QA/QC procedures should be sufficient to identify analytical problems, define criteria under which analysis of compliance samples will be suspended, and describe procedures for corrective actions.
3.3.1.1 QA/QC procedures for establishing control of CDB and CDU analyses
The QA/QC program for CDB and CDU should address, at a minimum, procedures involved in calibration, establishment of control limits, internal QC analyses and maintaining control, and corrective-action protocols. Participating laboratory should develop and maintain procedures to assure that analyses of compliance samples are within control limits, and that these procedures are documented thoroughly in a QA/QC plan.
A nonmandatory QA/QC protocol is presented in Attachment 1. This attachment is illustrative of the procedures that should be addressed in a proper QA/QC program.
Calibration. Before any analytic runs are conducted, the analytic instrument should be calibrated. Calibration should be performed at the beginning of each day on which QC and/or compliance samples are run. Once calibration is established, QC or compliance samples may be run. Regardless of the type of samples run, about every fifth sample should serve as a standard to assure that calibration is being maintained.
Calibration is being maintained if the standard is within ±15% of its theoretical value. If a standard is more than ±15% of its theoretical value, the run has exceeded control limits due to calibration error; the entire set of samples then should be reanalyzed after recalibrating or the results should be recalculated based on a statistical curve derived from that set of standards.
It is essential that the value of the highest standard analyzed be higher than the highest sample analyzed; it may be necessary, therefore, to run a high standard at the end of the run, which has been selected based on results obtained over the course of the run ( i.e., higher than any standard analyzed to that point).
Standards should be kept fresh; as samples age, they should be compared with new standards and replaced if necessary.
Internal Quality Control Analyses. Internal QC samples should be determined interspersed with analyses of compliance samples. At a minimum, these samples should be run at a rate of 5% of the compliance samples or at least one set of QC samples per analysis of compliance samples, whichever is greater. If only 2 samples are run, they should contain different levels of cadmium.
Internal QC samples may be obtained as commercially-available reference materials and/or they may be internally prepared. Internally-prepared samples should be well characterized and traced, or compared to a reference material for which a consensus value is available.
Levels of cadmium contained in QC samples should not be known to the analyst prior to reporting the results of the analysis.
Internal QC results should be plotted or charted in a manner which describes sample recovery and laboratory control limits.
Internal Control Limits. The laboratory protocol for evaluating internal QC analyses per control limits should be clearly defined. Limits may be based on statistical methods (e.g., as 2σ from the laboratory mean recovery), or on proficiency testing limits (e.g.,±1µg or 15% of the mean, whichever is greater). Statistical limits that exceed ±40% should be reevaluated to determine the source error in the analysis.
When laboratory limits are exceeded, analytic work should terminate until the source of error is determined and corrected; compliance samples affected by the error should be reanalyzed. In addition, the laboratory protocol should address any unusual trends that develop which may be biasing the results. Numerous, consecutive results above or below laboratory mean recoveries, or outside laboratory statistical limits, indicate that problems may have developed.
Corrective Actions. The QA/QC plan should document in detail specific actions taken if control limits are exceeded or unusual trends develop. Corrective actions should be noted on an appropriate form, accompanied by supporting documentation.
In addition to these actions, laboratories should include whatever additional actions are necessary to assure that accurate data are reported to the responsible physicians.
Reference Materials. The following reference materials may be available:
Cadmium in Blood (CDB)
1. Centre de Toxicologie du Quebec, Le Centre Hospitalier de l'Universite Laval, 2705 boul. Laurier, Quebec, Que., Canada G1V 4G2. (Prepared 6 times per year at 1-15 µg Cd/l.)
2. H. Marchandise, Community Bureau of Reference-BCR, Directorate General XII, Commission of the European Communities, 200, rue de la Loi, B-1049, Brussels, Belgium. (Prepared as Bl CBM-1 at 5.37 µg Cd/l, and Bl CBM-2 at 12.38 µg Cd/l.)
3. Kaulson Laboratories Inc., 691 Bloomfield Ave., Caldwell, NJ 07006; tel: (201) 226-9494, FAX (201) 226-3244. (Prepared as #0141 [As, Cd, Hg, Pb] at 2 levels.)
Cadmium in Urine (CDU)
1. Centre de Toxicologie du Quebec, Le Centre Hospitalier de l'Universite Laval, 2705 boul. Laurier, Quebec, Que., Canada G1V 4G2. (Prepared 6 times per year.)
2. National Institute of Standards and Technology (NIST), Dept. of Commerce, Gaithersburg, MD; tel: (301) 975-6776. (Prepared as SRM 2670 freeze-dried urine [metals]; set includes normal and elevated levels of metals; cadmium is certified for elevated level of 88.0 µg/l in reconstituted urine.)
3. Kaulson Laboratories Inc., 691 Bloomfield Ave., Caldwell, NJ 07006; tel: (201) 226-9494, FAX (201) 226-3244. (Prepared as #0140 [As, Cd, Hg, Pb] at 2 levels.)
3.3.1.2 QA/QC procedures for establishing control of B2MU
A written, detailed QA/QC plan for B2MU analysis should be developed. The QA/QC plan should contain a protocol similar to those protocols developed for the CDB/CDU analyses. Differences in analyses may warrant some differences in the QA/QC protocol, but procedures to ensure analytical integrity should be developed and followed.
Examples of performance summaries that can be provided include measurements of accuracy ( i.e., the means of measured values versus target values for the control samples) and precision ( i.e., based on duplicate analyses). It is recommended that the accuracy and precision measurements be compared to those reported as achievable by the Pharmacia Delphia kit (Pharmacia 1990) to determine if and when unsatisfactory analyses have arisen. If the measurement error of 1 or more of the control samples is more than 15%, the run exceeds control limits. Similarly, this decision is warranted when the average CV for duplicate samples is greater than 5%.
3.3.2 Procedures for Record Keeping
To satisfy reporting requirements for commercial analyses of CDB, CDU and/or B2MU performed for the medical monitoring program mandated under the cadmium rule, participating laboratories should maintain the following documentation for each analyte:
1. For each analytic instrument on which analyte determinations are made, records relating to the most recent calibration and QC sample analyses;
2. For these instruments, a tabulated record for each analyte of those determinations found to be within and outside of control limits over the past 2 years;
3. Results for the previous 2 years of the QC sample analyses conducted under the internal QA/QC program (this information should be: Provided for each analyte for which determinations are made and for each analytic instrument used for this purpose, sufficient to demonstrate that internal QA/QC programs are being executed properly, and consistent with data sent to responsible physicians.
4. Duplicate copies of monitoring results for each analyte sent to clients during the previous 5 years, as well as associated information; supporting material such as chain-of-custody forms also should be retained; and,
5. Proficiency test results and related materials received while participating in the CTQ interlaboratory program over the past 2 years; results also should be tabulated to provide a serial record of relative error (derived per Section 3.3.3 below).
3.3.3 Reporting Procedures
Participating laboratories should maintain these documents: QA/QC program plans; QA/QC status reports; CTQ proficiency program reports; and, analytical data reports. The information that should be included in these reports is summarized in Table 2; a copy of each report should be sent to the responsible physician.
| Report | Frequency (time frame) | Contents |
|---|---|---|
| 1 QA/QC Program Plan | Once (initially) | A detailed description of the QA/QC protocol to be established by the laboratory to maintain control of analyte determinations. |
| 2 QA/QC Status Report | Every 2 months | Results of the QC samples incorporated into regular runs for each instrument (over the period since the last report). |
| 3 Proficiency Report | Attached to every data report | Results from the last full year of proficiency samples submitted to the CTQ program and Results of the 100 most recent QC samples incorporated into regular runs for each instrument. |
| 4 Analytical Data Report | For all reports of data results | Date the sample was received; Date the sample was analyzed; Appropriate chain-of-custody information; Types of analyses performed; Results of the requested analyses and Copy of the most current proficiency report. |
As noted in Section 3.3.1, a QA/QC program plan should be developed that documents internal QA/QC procedures (defined under Section 3.3.1) to be implemented by the participating laboratory for each analyte; this plan should provide a list identifying each instrument used in making analyte determinations.
A QA/QC status report should be written bimonthly for each analyte. In this report, the results of the QC program during the reporting period should be reported for each analyte in the following manner: The number (N) of QC samples analyzed during the period; a table of the target levels defined for each sample and the corresponding measured values; the mean of F/T value (as defined below) for the set of QC samples run during the period; and, use of X ±2σ (as defined below) for the set of QC samples run during the period as a measure of precision.
As noted in Section 2, an F/T value for a QC sample is the ratio of the measured concentration of analyte to the established ( i.e., reference) concentration of analyte for that QC sample. The equation below describes the derivation of the mean for F/T values, X, (with N being the total number of samples analyzed):
The standard deviation, σ, for these measurements is derived using the following equation (note that 2σ is twice this value):
The nonmandatory QA/QC protocol (see Attachment 1) indicates that QC samples should be divided into several discrete pools, and a separate estimate of precision for each pools then should be derived. Several precision estimates should be provided for concentrations which differ in average value. These precision measures may be used to document improvements in performance with regard to the combined pool.
Participating laboratories should use the CTQ proficiency program for each analyte. Results of the this program will be sent by CTQ directly to physicians designated by the participating laboratories. Proficiency results from the CTQ program are used to establish the accuracy of results from each participating laboratory, and should be provided to responsible physicians for use in trend analysis. A proficiency report consisting of these proficiency results should accompany data reports as an attachment.
For each analyte, the proficiency report should include the results from the 6 previous proficiency rounds in the following format:
1. Number (N) of samples analyzed;
2. Mean of the target levels, (1/N)Σ i, with T i being a consensus mean for the sample;
3. Mean of the measurements, (1/N)Σ i, with M i being a sample measurement;
4. A measure of error defined by:
i
i
2
Analytical data reports should be submitted to responsible physicians directly. For each sample, report the following information: The date the sample was received; the date the sample was analyzed; appropriate chain-of-custody information; the type(s) of analyses performed; and, the results of the analyses. This information should be reported on a form similar to the form provided an appropriate form. The most recent proficiency program report should accompany the analytical data reports (as an attachment).
Confidence intervals for the analytical results should be reported as X±2σ, with X being the measured value and 2σ the standard deviation calculated as described above.
For CDU or B2MU results, which are combined with CRTU measurements for proper reporting, the 95% confidence limits are derived from the limits for CDU or B2MU, (p), and the limits for CRTU, (q), as follows:
For these calculations, X ±p is the measurement and confidence limits for CDU or B2MU, and Y ±q is the measurement and confidence limit for CRTU.
Participating laboratories should notify responsible physicians as soon as they receive information indicating a change in their accreditation status with the CTQ or the CAP. These physicians should not be expected to wait until formal notice of a status change has been received from the CTQ or the CAP.
3.4 Instructions to Physicians
Physicians responsible for the medical monitoring of cadmium-exposed workers must collect the biological samples from workers; they then should select laboratories to perform the required analyses, and should interpret the analytic results.
3.4.1 Sample Collection and Holding Procedures
Blood Samples. The following procedures are recommended for the collection, shipment and storage of blood samples for CDB analysis to reduce analytical variablility; these recommendations were obtained primarily through personal communications with J.P. Weber of the CTQ (1991), and from reports by the Centers for Disease Control (CDC, 1986) and Stoeppler and Brandt (1980).
To the extent possible, blood samples should be collected from workers at the same time of day. Workers should shower or thoroughly wash their hands and arms before blood samples are drawn. The following materials are needed for blood sample collection: Alcohol wipes; sterile gauze sponges; band-aids; 20-gauge, 1.5-in. stainless steel needles (sterile); preprinted labels; tourniquets; vacutainer holders; 3-ml “metal free” vacutainer tubes ( i.e., dark-blue caps), with EDTA as an anti-coagulant; and, styrofoam vacutainer shipping containers.
Whole blood samples are taken by venipuncture. Each blue-capped tube should be labeled or coded for the worker and company before the sample is drawn. (Blue-capped tubes are recommended instead of red-capped tubes because the latter may consist of red coloring pigment containing cadmium, which could contaminate the samples.) Immediately after sampling, the vacutainer tubes must be thoroughly mixed by inverting the tubes at least 10 times manually or mechanically using a Vortex device (for 15 sec). Samples should be refrigerated immediately or stored on ice until they can be packed for shipment to the participating laboratory for analysis.
The CDC recommends that blood samples be shipped with a “cool pak” to keep the samples cold during shipment. However, the CTQ routinely ships and receives blood samples for cadmium analysis that have not been kept cool during shipment. The CTQ has found no deterioration of cadmium in biological fluids that were shipped via parcel post without a cooling agent, even though these deliveries often take 2 weeks to reach their destination.
Urine Samples. The following are recommended procedures for the collection, shipment and storage of urine for CDU and B2MU analyses, and were obtained primarily through personal communications with J.P. Weber of the CTQ (1991), and from reports by the CDC (1986) and Stoeppler and Brandt (1980).
Single “spot” samples are recommended. As B2M can degrade in the bladder, workers should first empty their bladder and then drink a large glass of water at the start of the visit. Urine samples then should be collected within 1 hour. Separate samples should be collected for CDU and B2MU using the following materials: Sterile urine collection cups (250 ml); small sealable plastic bags; preprinted labels; 15-ml polypropylene or polyethylene screw-cap tubes; lab gloves (“metal free”); and, preservatives (as indicated).
The sealed collection cup should be kept in the plastic bag until collection time. The workers should wash their hands with soap and water before receiving the collection cup. The collection cup should not be opened until just before voiding and the cup should be sealed immediately after filling. It is important that the inside of the container and cap are not touched by, or come into contact with, the body, clothing or other surfaces.
For CDU analyzes, the cup is swirled gently to resuspend any solids, and the 15-ml tube is filled with 10-12 ml urine. The CDC recommends the addition of 100 µl concentrated HNO 3 as a preservative before sealing the tube and then freezing the sample. The CTQ recommends minimal handling and does not acidify their interlaboratory urine reference materials prior to shipment, nor do they freeze the sample for shipment. At the CTQ, if the urine sample has much sediment, the sample is acidified in the lab to free any cadmium in the precipitate.
For B2M, the urine sample should be collected directly into a polyethylene bottle previously washed with dilute nitric acid. The pH of the urine should be measured and adjusted to 8.0 with 0.1 N NaOH immediately following collection. Samples should be frozen and stored at −20 °C until testing is performed. The B2M in the samples should be stable for 2 days when stored at 2-8 °C, and for at least 2 months at −20 °C. Repeated freezing and thawing should be avoided to prevent denaturing the B2M (Pharmacia 1990).
3.4.2 Recommendations for Evaluating Laboratories
Using standard error data and the results of proficiency testing obtained from CTQ, responsible physicians can make an informed choice of which laboratory to select to analyze biological samples. In general, laboratories with small standard errors and little disparity between target and measured values tend to make precise and accurate sample determinations. Estimates of precision provided to the physicians with each set of monitoring results can be compared to previously-reported proficiency and precision estimates. The latest precision estimates should be at least as small as the standard error reported previously by the laboratory. Moreover, there should be no indication that precision is deteriorating ( i.e., increasing values for the precision estimates). If precision is deteriorating, physicians may decide to use another laboratory for these analyses. QA/QC information provided by the participating laboratories to physicians can, therefore, assist physicians in evaluating laboratory performance.
3.4.3 Use and Interpretation of Results
When the responsible physician has received the CDB, CDU and/or B2MU results, these results must be compared to the action levels discussed in the final rule for cadmium. The comparison of the sample results to action levels is straightforward. The measured value reported from the laboratory can be compared directly to the action levels; if the reported value exceeds an action level, the required actions must be initiated.
4.0 Background
Cadmium is a naturally-occurring environmental contaminant to which humans are continually exposed in food, water, and air. The average daily intake of cadmium by the U.S. population is estimated to be 10-20 µg/day. Most of this intake is via ingestion, for which absorption is estimated at 4-7% (Kowal et al. 1979). An additional nonoccupational source of cadmium is smoking tobacco; smoking a pack of cigarettes a day adds an additional 2-4 µg cadmium to the daily intake, assuming absorption via inhalation of 25-35% (Nordberg and Nordberg 1988; Friberg and Elinder 1988; Travis and Haddock 1980).
Exposure to cadmium fumes and dusts in an occupational setting where air concentrations are 20-50 µg/m 3 results in an additional daily intake of several hundred micrograms (Friberg and Elinder 1988, p. 563). In such a setting, occupational exposure to cadmium occurs primarily via inhalation, although additional exposure may occur through the ingestion of material via contaminated hands if workers eat or smoke without first washing. Some of the particles that are inhaled initially may be ingested when the material is deposited in the upper respiratory tract, where it may be cleared by mucociliary transport and subsequently swallowed.
Cadmium introduced into the body through inhalation or ingestion is transported by the albumin fraction of the blood plasma to the liver, where it accumulates and is stored principally as a bound form complexed with the protein metallothionein. Metallothionein-bound cadmium is the main form of cadmium subsequently transported to the kidney; it is these 2 organs, the liver and kidney, in which the majority of the cadmium body burden accumulates. As much as one half of the total body burden of cadmium may be found in the kidneys (Nordberg and Nordberg 1988).
Once cadmium has entered the body, elimination is slow; about 0.02% of the body burden is excreted per day via urinary/fecal elimination. The whole-body half-life of cadmium is 10-35 years, decreasing slightly with increasing age (Travis and Haddock 1980).
The continual accumulation of cadmium is the basis for its chronic noncarcinogenic toxicity. This accumulation makes the kidney the target organ in which cadmium toxicity usually is first observed (Piscator 1964). Renal damage may occur when cadmium levels in the kidney cortex approach 200 µg/g wet tissue-weight (Travis and Haddock 1980).
The kinetics and internal distribution of cadmium in the body are complex, and depend on whether occupational exposure to cadmium is ongoing or has terminated. In general, cadmium in blood is related principally to recent cadmium exposure, while cadmium in urine reflects cumulative exposure ( i.e., total body burden) (Lauwerys et al. 1976; Friberg and Elinder 1988).
4.1 Health Effects
Studies of workers in a variety of industries indicate that chronic exposure to cadmium may be linked to several adverse health effects including kidney dysfunction, reduced pulmonary function, chronic lung disease and cancer ( Federal Register 1990). The primary sites for cadmium-associated cancer appear to be the lung and the prostate.
Cancer. Evidence for an association between cancer and cadmium exposure comes from both epidemiological studies and animal experiments. Pott (1965) found a statistically significant elevation in the incidence of prostate cancer among a cohort of cadmium workers. Other epidemiology studies also report an elevated incidence of prostate cancer; however, the increases observed in these other studies were not statistically significant (Meridian Research, Inc. 1989).
One study (Thun et al. 1985) contains sufficiently quantitative estimates of cadmium exposure to allow evaluation of dose-response relationships between cadmium exposure and lung cancer. A statistically significant excess of lung cancer attributed to cadmium exposure was found in this study, even after accounting for confounding variables such as coexposure to arsenic and smoking habits (Meridian Research, Inc. 1989).
Evidence for quantifying a link between lung cancer and cadmium exposure comes from a single study (Takenaka et al. 1983). In this study, dose-response relationships developed from animal data were extrapolated to humans using a variety of models. OSHA chose the multistage risk model for estimating the risk of cancer for humans using these animal data. Animal injection studies also suggest an association between cadmium exposure and cancer, particularly observations of an increased incidence of tumors at sites remote from the point of injection. The International Agency for Research on Cancer (IARC) (Supplement 7, 1987) indicates that this, and related, evidence is sufficient to classify cadmium as an animal carcinogen. However, the results of these injection studies cannot be used to quantify risks attendant to human occupational exposures due to differences in routes of exposure (Meridian Research, Inc. 1989).
Based on the above-cited studies, the U.S. Environmental Protection Agency (EPA) classifies cadmium as “B1,” a probable human carcinogen (USEPA 1985). IARC in 1987 recommended that cadmium be listed as a probable human carcinogen.
Kidney Dysfunction. The most prevalent nonmalignant effect observed among workers chronically exposed to cadmium is kidney dysfunction. Initially, such dysfunction is manifested by proteinuria (Meridian Research, Inc. 1989; Roth Associates, Inc. 1989). Proteinuria associated with cadmium exposure is most commonly characterized by excretion of low-molecular weight proteins (15,000-40,000 MW), accompanied by loss of electrolytes, uric acid, calcium, amino acids, and phosphate. Proteins commonly excreted include β-2-microglobulin (B2M), retinol-binding protein (RBP), immunoglobulin light chains, and lysozyme. Excretion of low molecular weight proteins is characteristic of damage to the proximal tubules of the kidney (Iwao et al. 1980).
Exposure to cadmium also may lead to urinary excretion of high-molecular weight proteins such as albumin, immunoglobulin G, and glycoproteins (Meridian Research, Inc. 1989; Roth Associates, Inc. 1989). Excretion of high-molecular weight proteins is indicative of damage to the glomeruli of the kidney. Bernard et al. (1979) suggest that cadmium-associated damage to the glomeruli and damage to the proximal tubules of the kidney develop independently of each other, but may occur in the same individual.
Several studies indicate that the onset of low-molecular weight proteinuria is a sign of irreversible kidney damage (Friberg et al. 1974; Roels et al. 1982; Piscator 1984; Elinder et al. 1985; Smith et al. 1986). For many workers, once sufficiently elevated levels of B2M are observed in association with cadmium exposure, such levels do not appear to return to normal even when cadmium exposure is eliminated by removal of the worker from the cadmium-contaminated work environment (Friberg, exhibit 29, 1990).
Some studies indicate that cadmium-induced proteinuria may be progressive; levels of B2MU increase even after cadmium exposure has ceased (Elinder et al. 1985). Other researchers have reached similar conclusions (Frieburg testimony, OSHA docket exhibit 29, Elinder testimony, OSHA docket exhibit 55, and OSHA docket exhibits 8-86B). Such observations are not universal, however (Smith et al. 1986; Tsuchiya 1976). Studies in which proteinuria has not been observed, however, may have initiated the reassessment too early (Meridian Research, Inc.1989; Roth Associates, Inc. 1989; Roels 1989).
A quantitative assessment of the risks of developing kidney dysfunction as a result of cadmium exposure was performed using the data from Ellis et al. (1984) and Falck et al. (1983). Meridian Research, Inc. (1989) and Roth Associates, Inc. (1989) employed several mathematical models to evaluate the data from the 2 studies, and the results indicate that cumulative cadmium exposure levels between 5 and 100 µg-years/m 3 correspond with a one-in-a-thousand probability of developing kidney dysfunction.
When cadmium exposure continues past the onset of early kidney damage (manifested as proteinuria), chronic nephrotoxicity may occur (Meridian Research, Inc. 1989; Roth Associates, Inc. 1989). Uremia, which is the loss of the glomerulus' ability to adequately filter blood, may result. This condition leads to severe disturbance of electrolyte concentrations, which may result in various clinical complications including atherosclerosis, hypertension, pericarditis, anemia, hemorrhagic tendencies, deficient cellular immunity, bone changes, and other problems. Progression of the disease may require dialysis or a kidney transplant.
Studies in which animals are chronically exposed to cadmium confirm the renal effects observed in humans (Friberg et al. 1986). Animal studies also confirm cadmium-related problems with calcium metabolism and associated skeletal effects, which also have been observed among humans. Other effects commonly reported in chronic animal studies include anemia, changes in liver morphology, immunosuppression and hypertension. Some of these effects may be associated with cofactors; hypertension, for example, appears to be associated with diet, as well as with cadmium exposure. Animals injected with cadmium also have shown testicular necrosis.
4.2 Objectives for Medical Monitoring
In keeping with the observation that renal disease tends to be the earliest clinical manifestation of cadmium toxicity, the final cadmium standard mandates that eligible workers must be medically monitored to prevent this condition (as well as cadmimum-induced cancer). The objectives of medical-monitoring, therefore, are to: Identify workers at significant risk of adverse health effects from excess, chronic exposure to cadmium; prevent future cases of cadmium-induced disease; detect and minimize existing cadmium-induced disease; and, identify workers most in need of medical intervention.
The overall goal of the medical monitoring program is to protect workers who may be exposed continuously to cadmium over a 45-year occupational lifespan. Consistent with this goal, the medical monitoring program should assure that:
1. Current exposure levels remain sufficiently low to prevent the accumulation of cadmium body burdens sufficient to cause disease in the future by monitoring CDB as an indicator of recent cadmium exposure;
2. Cumulative body burdens, especially among workers with undefined historical exposures, remain below levels potentially capable of leading to damage and disease by assessing CDU as an indicator of cumulative exposure to cadmium; and,
3. Health effects are not occurring among exposed workers by determining B2MU as an early indicator of the onset of cadmium-induced kidney disease.
4.3 Indicators of Cadmium Exposure and Disease
Cadmium is present in whole blood bound to albumin, in erythrocytes, and as a metallothionein-cadmium complex. The metallothionein-cadmium complex that represents the primary transport mechanism for cadmium delivery to the kidney. CDB concentrations in the general, nonexposed population average 1 µg Cd/l whole blood, with smokers exhibiting higher levels (see Section 5.1.6). Data presented in Section 5.1.6 shows that 95% of the general population not occupationally exposed to cadmium have CDB levels less than 5 µg Cd/l.
If total body burdens of cadmium remain low, CDB concentrations indicate recent exposure ( i.e., daily intake). This conclusion is based on data showing that cigarette smokers exhibit CDB concentrations of 2-7 µg/l depending on the number of cigarettes smoked per day (Nordberg and Nordberg 1988), while CDB levels for those who quit smoking return to general population values (approximately 1 µg/l) within several weeks (Lauwerys et al. 1976). Based on these observations, Lauwerys et al. (1976) concluded that CDB has a biological half-life of a few weeks to less than 3 months. As indicated in Section 3.1.6, the upper 95th percentile for CDB levels observed among those who are not occupationally exposed to cadmium is 5 µg/l, which suggests that the absolute upper limit to the range reported for smokers by Nordberg and Nordberg may have been affected by an extreme value ( i.e., beyond 2σ above the mean).
Among occupationally-exposed workers, the occupational history of exposure to cadmium must be evaluated to interpret CDB levels. New workers, or workers with low exposures to cadmium, exhibit CDB levels that are representative of recent exposures, similar to the general population. However, for workers with a history of chronic exposure to cadmium, who have accumulated significant stores of cadmium in the kidneys/liver, part of the CDB concentrations appear to indicate body burden. If such workers are removed from cadmium exposure, their CDB levels remain elevated, possibly for years, reflecting prior long-term accumulation of cadmium in body tissues. This condition tends to occur, however, only beyond some threshold exposure value, and possibly indicates the capacity of body tissues to accumulate cadmium which cannot be excreted readily (Friberg and Elinder 1988; Nordberg and Nordberg 1988).
CDU is widely used as an indicator of cadmium body burdens (Nordberg and Nordberg 1988). CDU is the major route of elimination and, when CDU is measured, it is commonly expressed either as µg Cd/l urine (unadjusted), µg Cd/l urine (adjusted for specific gravity), or µg Cd/g CRTU (see Section 5.2.1). The metabolic model for CDU is less complicated than CDB, since CDU is dependentin large part on the body ( i.e., kidney) burden of cadmium. However, a small proportion of CDU still be attributed to recent cadmium exposure, particularly if exposure to high airborne concentrations of cadmium occurred. Note that CDU is subject to larger interindividual and day-to-day variations than CDB, so repeated measurements are recommended for CDU evaluations.
CDU is bound principally to metallothionein, regardless of whether the cadmium originates from metallothionein in plasma or from the cadmium pool accumulated in the renal tubules. Therefore, measurement of metallothionein in urine may provide information similar to CDU, while avoiding the contamination problems that may occur during collection and handling urine for cadmium analysis (Nordberg and Nordberg 1988). However, a commercial method for the determination of metallothionein at the sensitivity levels required under the final cadmium rule is not currently available; therefore, analysis of CDU is recommended.
Among the general population not occupationally exposed to cadmium, CDU levels average less than 1 µg/l (see Section 5.2.7). Normalized for creatinine (CRTU), the average CDU concentration of the general population is less than 1 µg/g CRTU. As cadmium accumulates over the lifespan, CDU increases with age. Also, cigarette smokers may eventually accumulate twice the cadmium body burden of nonsmokers, CDU is slightly higher in smokers than in nonsmokers, even several years after smoking cessation (Nordberg and Nordberg 1988). Despite variations due to age and smoking habits, 95% of those not occupationally exposed to cadmium exhibit levels of CDU less than 3 µg/g CRTU (based on the data presented in Section 5.2.7).
About 0.02% of the cadmium body burden is excreted daily in urine. When the critical cadmium concentration (about 200 ppm) in the kidney is reached, or if there is sufficient cadmium-induced kidney dysfunction, dramatic increases in CDU are observed (Nordberg and Nordberg 1988). Above 200 ppm, therefore, CDU concentrations cease to be an indicator of cadmium body burden, and are instead an index of kidney failure.
Proteinuria is an index of kidney dysfunction, and is defined by OSHA to be a material impairment. Several small proteins may be monitored as markers for proteinuria. Below levels indicative of proteinuria, these small proteins may be early indicators of increased risk of cadmium-induced renal tubular disease. Analytes useful for monitoring cadmium-induced renal tubular damage include:
1. β-2-Microglobulin (B2M), currently the most widely used assay for detecting kidney dysfunction, is the best characterized analyte available (Iwao et al. 1980; Chia et al. 1989);
2. Retinol Binding Protein (RBP) is more stable than B2M in acidic urine ( i.e., B2M breakdown occurs if urinary pH is less than 5.5; such breakdown may result in false [i.e., low] B2M values [Bernard and Lauwerys, 1990]);
3. N-Acetyl-B-Glucosaminidase (NAG) is the analyte of an assay that is simple, inexpensive, reliable, and correlates with cadmium levels under 10 µg/g CRTU, but the assay is less sensitive than RBP or B2M (Kawada et al. 1989);
4. Metallothionein (MT) correlates with cadmium and B2M levels, and may be a better predictor of cadmium exposure than CDU and B2M (Kawada et al. 1989);
5. Tamm-Horsfall Glycoprotein (THG) increases slightly with elevated cadmium levels, but this elevation is small compared to increases in urinary albumin, RBP, or B2M (Bernard and Lauwerys 1990);
6. Albumin (ALB), determined by the biuret method, is not sufficiently sensitive to serve as an early indicator of the onset of renal disease (Piscator 1962);
7. Albumin (ALB), determined by the Amido Black method, is sensitive and reproducible, but involves a time-consuming procedure (Piscator 1962);
8. Glycosaminoglycan (GAG) increases among cadmium workers, but the significance of this effect is unknown because no relationship has been found between elevated GAG and other indices of tubular damage (Bernard and Lauwerys 1990);
9. Trehalase seems to increase earlier than B2M during cadmium exposure, but the procedure for analysis is complicated and unreliable (Iwata et al. 1988); and,
10. Kallikrein is observed at lower concentrations among cadmium-exposed workers than among normal controls (Roels et al. 1990).
Of the above analytes, B2M appears to be the most widely used and best characterized analyte to evaluate the presence/absence, as well as the extent of, cadmium-induced renal tubular damage (Kawada, Koyama, and Suzuki 1989; Shaikh and Smith 1984; Nogawa 1984). However, it is important that samples be collected and handled so as to minimize B2M degradation under acidic urine conditions.
The threshold value of B2MU commonly used to indicate the presence of kidney damage 300 µg/g CRTU (Kjellstrom et al. 1977a; Buchet et al. 1980; and Kowal and Zirkes 1983). This value represents the upper 95th or 97.5th percentile level of urinary excretion observed among those without tubular dysfunction (Elinder, exbt L-140-45, OSHA docket H057A). In agreement with these conclusions, the data presented in Section 5.3.7 of this protocol generally indicate that the level of 300 µg/g CRTU appears to define the boundary for kidney dysfunction. It is not clear, however, that this level represents the upper 95th percentile of values observed among those who fail to demonstrate proteinuria effects.
Although elevated B2MU levels appear to be a fairly specific indicator of disease associated with cadmium exposure, other conditions that may lead to elevated B2MU levels include high fevers from influenza, extensive physical exercise, renal disease unrelated to cadmium exposure, lymphomas, and AIDS (Iwao et al. 1980; Schardun and van Epps 1987). Elevated B2M levels observed in association with high fevers from influenza or from extensive physical exercise are transient, and will return to normal levels once the fever has abated or metabolic rates return to baseline values following exercise. The other conditions linked to elevated B2M levels can be diagnosed as part of a properly-designed medical examination. Consequently, monitoring B2M, when accompanied by regular medical examinations and CDB and CDU determinations (as indicators of present and past cadmium exposure), may serve as a specific, early indicator of cadmium-induced kidney damage.
4.4 Criteria for Medical Monitoring of Cadmium Workers
Medical monitoring mandated by the final cadmium rule includes a combination of regular medical examinations and periodic monitoring of 3 analytes: CDB, CDU and B2MU. As indicated above, CDB is monitored as an indicator of current cadmium exposure, while CDU serves as an indicator of the cadmium body burden; B2MU is assessed as an early marker of irreversible kidney damage and disease.
The final cadmium rule defines a series of action levels that have been developed for each of the 3 analytes to be monitored. These action levels serve to guide the responsible physician through a decision-making process. For each action level that is exceeded, a specific response is mandated. The sequence of action levels, and the attendant actions, are described in detail in the final cadmium rule.
Other criteria used in the medical decision-making process relate to tests performed during the medical examination (including a determination of the ability of a worker to wear a respirator). These criteria, however, are not affected by the results of the analyte determinations addressed in the above paragraphs and, consequently, will not be considered further in these guidelines.
4.5 Defining to Quality and Proficiency of the Analyte Determinations
As noted above in Sections 2 and 3, the quality of a measurement should be defined along with its value to properly interpret the results. Generally, it is necessary to know the accuracy and the precision of a measurement before it can be properly evaluated. The precision of the data from a specific laboratory indicates the extent to which the repeated measurements of the same sample vary within that laboratory. The accuracy of the data provides an indication of the extent to which these results deviate from average results determined from many laboratories performing the same measurement ( i.e., in the absence of an independent determination of the true value of a measurement). Note that terms are defined operationally relative to the manner in which they will be used in this protocol. Formal definitions for the terms in italics used in this section can be found in the list of definitions (Section 2).
Another data quality criterion required to properly evaluate measurement results is the limit of detection of that measurement. For measurements to be useful, the range of the measurement which is of interest for biological monitoring purposes must lie entirely above the limit of detection defined for that measurement.
The overall quality of a laboratory's results is termed the performance of that laboratory. The degree to which a laboratory satisfies a minimum performance level is referred to as the proficiency of the laboratory. A successful medical monitoring program, therefore, should include procedures developed for monitoring and recording laboratory performance; these procedures can be used to identify the most proficient laboratories.
5.0 Overview of Medical Monitoring Tests for CDB, CDU, B2MU and CRTU
To evaluate whether available methods for assessing CDB, CDU, B2MU and CRTU are adequate for determining the parameters defined by the proposed action levels, it is necessary to review procedures available for sample collection, preparation and analysis. A variety of techniques for these purposes have been used historically for the determination of cadmium in biological matrices (including CDB and CDU), and for the determination of specific proteins in biological matrices (including B2MU). However, only the most recent techniques are capable of satisfying the required accuracy, precision and sensitivity ( i.e., limit of detection) for monitoring at the levels mandated in the final cadmium rule, while still facilitating automated analysis and rapid processing.
5.1 Measuring Cadmium in Blood (CDB)
Analysis of biological samples for cadmium requires strict analytical discipline regarding collection and handling of samples. In addition to occupational settings, where cadmium contamination would be apparent, cadmium is a ubiquitous environmental contaminant, and much care should be exercised to ensure that samples are not contaminated during collection, preparation or analysis. Many common chemical reagents are contaminated with cadmium at concentrations that will interfere with cadmium analysis; because of the widespread use of cadmium compounds as colored pigments in plastics and coatings, the analyst should continually monitor each manufacturer's chemical reagents and collection containers to prevent contamination of samples.
Guarding against cadmium contamination of biological samples is particularly important when analyzing blood samples because cadmium concentrations in blood samples from nonexposed populations are generally less than 2 µg/l (2 ng/ml), while occupationally-exposed workers can be at medical risk to cadmium toxicity if blood concentrations exceed 5 µg/l (ACGIH 1991 and 1992). This narrow margin between exposed and unexposed samples requires that exceptional care be used in performing analytic determinations for biological monitoring for occupational cadmium exposure.
Methods for quantifying cadmium in blood have improved over the last 40 years primarily because of improvements in analytical instrumentation. Also, due to improvements in analytical techniques, there is less need to perform extensive multi-step sample preparations prior to analysis. Complex sample preparation was previously required to enhance method sensitivity (for cadmium), and to reduce interference by other metals or components of the sample.
5.1.1 Analytical Techniques Used To Monitor Cadmium in Biological Matrices
| Analytical procedure | Limit of detection [ng/(g or ml)] | Specified biological matrix | Reference | Comments |
|---|---|---|---|---|
| Flame Atomic Absorption Spectroscopy (FAAS) | ≥1.0 | Any matrix | Perkin-Elmer (1982) | Not sensitive enough for biomonitoring without extensive sample digestion, metal chelation and organic solvent extraction. |
| Graphite Furnace Atomic Absorption Spectroscopy (GFAAS) | 0.04 | Urine | Pruszkowska et al. (1983) | Methods of choice for routine cadmium analysis. |
| ≥0.20 | Blood | Stoeppler and Brandt (1980) | ||
| Inductively-Coupled Argon-Plasma Atomic Emission Spectroscopy (ICAP AES) | 2.0 | Any matrix | NIOSH (1984A) | Requires extensive sample preparation and concentration of metal with chelating resin. Advantage is simultaneous analyses for as many as 10 metals from 1 sample. |
| Neutron Activation Gamma Spectroscopy (NA) | 1.5 | In vivo (liver) | Ellis et al. (1983) | Only available in vivo method for direct determination of cadmium body tissue burdens; expensive; absolute determination of cadmium in reference materials. |
| Isotope Dilution Mass Spectroscopy (IDMS) | <1.0 | Any matrix | Michiels and DeBievre (1986) | Suitable for absolute determination of cadmium in reference materials; expensive. |
| Differential Pulse Anodic Stripping Voltammetry (DPASV) | <1.0 | Any matrix | Stoeppler and Brandt (1980) | Suitable for absolute determination of cadmium in reference materials; efficient method to check accuracy of analytical method. |
A number of analytical techniques have been used for determining cadmium concentrations in biological materials. A summary of the characteristics of the most widely employed techniques is presented in Table 3. The technique most suitable for medical monitoring for cadmium is atomic absorption spectroscopy (AAS).
To obtain a measurement using AAS, a light source ( i.e., hollow cathode or lectrode-free discharge lamp) containing the element of interest as the cathode, is energized and the lamp emits a spectrum that is unique for that element. This light source is focused through a sample cell, and a selected wavelength is monitored by a monochrometer and photodetector cell. Any ground state atoms in the sample that match those of the lamp element and are in the path of the emitted light may absorb some of the light and decrease the amount of light that reaches the photodetector cell. The amount of light absorbed at each characteristic wavelength is proportional to the number of ground state atoms of the corresponding element that are in the pathway of the light between the source and detector.
To determine the amount of a specific metallic element in a sample using AAS, the sample is dissolved in a solvent and aspirated into a high-temperature flame as an aerosol. At high temperatures, the solvent is rapidly evaporated or decomposed and the solute is initially solidified; the majority of the sample elements then are transformed into an atomic vapor. Next, a light beam is focused above the flame and the amount of metal in the sample can be determined by measuring the degree of absorbance of the atoms of the target element released by the flame at a characteristic wavelength.
A more refined atomic absorption technique, flameless AAS, substitutes an electrothermal, graphite furnace for the flame. An aliquot (10-100 µl) of the sample is pipetted into the cold furnace, which is then heated rapidly to generate an atomic vapor of the element.
AAS is a sensitive and specific method for the elemental analysis of metals; its main drawback is nonspecific background absorbtion and scattering of the light beam by particles of the sample as it decomposes at high temperatures; nonspecific absorbance reduces the sensitivity of the analytical method. The problem of nonspecific absorbance and scattering can be reduced by extensive sample pretreatment, such as ashing and/or acid digestion of the sample to reduce its organic content.
Current AAS instruments employ background correction devices to adjust electronically for background absorbtion and scattering. A common method to correct for background effects is to use a deuterium arc lamp as a second light source. A continuum light source, such as the deuterium lamp, emits a broad spectrum of wavelengths instead of specific wavelengths characteristic of a particular element, as with the hollow cathode tube. With this system, light from the primary source and the continuum source are passed alternately through the sample cell. The target element effectively absorbs light only from the primary source (which is much brighter than the continuum source at the characteristic wavelengths), while the background matrix absorbs and scatters light from both sources equally. Therefore, when the ratio of the two beams is measured electronically, the effect of nonspecific background absorption and scattering is eliminated. A less common, but more sophisticated, backgrond correction system is based on the Zeeman effect, which uses a magnetically-activated light polarizer to compensate electronically for nonspecific absorbtion and scattering.
Atomic emission spectroscopy with inductively-coupled argon plasma (AES-ICAP) is widely used to analyze for metals. With this instrument, the sample is aspirated into an extremely hot argon plasma flame, which excites the metal atoms; emission spectra specific for the sample element then are generated. The quanta of emitted light passing through a monochrometer are amplified by photomultiplier tubes and measured by a photodetector to determine the amount of metal in the sample. An advantage of AES-ICAP over AAS is that multi-elemental analyses of a sample can be performed by simultaneously measuring specific elemental emission energies. However, AES-ICAP lacks the sensitivity of AAS, exhibiting a limit of detection which is higher than the limit of detection for graphite-furnace AAS (Table 3).
Neutron activation (NA) analysis and isotope dilution mass spectrometry (IDMS) are 2 additional, but highly specialized, methods that have been used for cadmium determinations. These methods are expensive because they require elaborate and sophisticated instrumentation.
NA analysis has the distinct advantage over other analytical methods of being able to determine cadmium body burdens in specific organs (e.g., liver, kidney) in vivo (Ellis et al. 1983). Neutron bombardment of the target transforms cadmium-113 to cadmium-114, which promptly decays (<10 −14 sec) to its ground state, emitting gamma rays that are measured using large gamma detectors; appropriate shielding and instrumentation are required when using this method.
IDMS analysis, a definitive but laborious method, is based on the change in the ratio of 2 isotopes of cadmium (cadmium 111 and 112) that occurs when a known amount of the element (with an artificially altered ratio of the same isotopes [i.e., a cadmium 111 “spike”] is added to a weighed aliquot of the sample (Michiels and De Bievre 1986).
5.1.2 Methods Developed for CDB Determinations
A variety of methods have been used for preparing and analyzing CDB samples; most of these methods rely on one of the analytical techniques described above. Among the earliest reports, Princi (1947) and Smith et al. (1955) employed a colorimetric procedure to analyze for CDB and CDU. Samples were dried and digested through several cycles with concentrated mineral acids (HNO 3 and H 2 SO 4 ) and hydrogen peroxide (H 2 O 2 ). The digest was neutralized, and the cadmium was complexed with diphenylthiocarbazone and extracted with chloroform. The dithizone-cadmium complex then was quantified using a spectrometer.
Colorimetric procedures for cadmium analyses were replaced by methods based on atomic absorption spectroscopy (AAS) in the early 1960s, but many of the complex sample preparation procedures were retained. Kjellstrom (1979) reports that in Japanese, American and Swedish laboratories during the early 1970s, blood samples were wet ashed with mineral acids or ashed at high temperature and wetted with nitric acid. The cadmium in the digest was complexed with metal chelators including diethyl dithiocarbamate (DDTC), ammonium pyrrolidine dithiocarbamate (APDC) or diphenylthiocarbazone (dithizone) in ammonia-citrate buffer and extracted with methyl isobutyl ketone (MIBK). The resulting solution then was analyzed by flame AAS or graphite-furnace AAS forcadmium determinations using deuterium-lamp background correction.
In the late 1970s, researchers began developing simpler preparation procedures. Roels et al. (1978) and Roberts and Clark (1986) developed simplified digestion procedures. Using the Roberts and Clark method, a 0.5 ml aliquot of blood is collected and transferred to a digestion tube containing 1 ml concentrated HNO 3. The blood is then digested at 110 °C for 4 hours. The sample is reduced in volume by continued heating, and 0.5 ml 30% H 2 O 2 is added as the sample dries. The residue is dissolved in 5 ml dilute (1%) HNO 3, and 20 µl of sample is then analyzed by graphite-furnace AAS with deuterium-background correction.
The current trend in the preparation of blood samples is to dilute the sample and add matrix modifiers to reduce background interference, rather than digesting the sample to reduce organic content. The method of Stoeppler and Brandt (1980), and the abbreviated procedure published in the American Public Health Association's (APHA) Methods for Biological Monitoring (1988), are straightforward and are nearly identical. For the APHA method, a small aliquot (50-300 µl) of whole blood that has been stabilized with ethylenediaminetetraacetate (EDTA) is added to 1.0 ml 1MHNO 3, vigorously shaken and centrifuged. Aliquots (10-25 µl) of the supernatant then are then analyzed by graphite-furnace AAS with appropriate background correction.
Using the method of Stoeppler and Brandt (1980), aliquots (50-200 µl) of whole blood that have been stabilized with EDTA are pipetted into clean polystyrene tubes and mixed with 150-600 µl of 1 M HNO 3. After vigorous shaking, the solution is centrifuged and a 10-25 µl aliquot of the supernatant then is analyzed by graphite-furnace AAS with appropriate background correction.
Claeys-Thoreau (1982) and DeBenzo et al. (1990) diluted blood samples at a ratio of 1:10 with a matrix modifier (0.2% Triton X-100, a wetting agent) for direct determinations of CDB. DeBenzo et al. also demonstrated that aqueous standards of cadmium, instead of spiked, whole-blood samples, could be used to establish calibration curves if standards and samples are treated with additional small volumes of matrix modifiers ( i.e., 1% HNO 3, 0.2% ammonium hydrogenphosphate and 1 mg/ml magnesium salts).
These direct dilution procedures for CDB analysis are simple and rapid. Laboratories can process more than 100 samples a day using a dedicated graphite-furnace AAS, an auto-sampler, and either a Zeeman- or a deuterium-background correction system. Several authors emphasize using optimum settings for graphite-furnace temperatures during the drying, charring, and atomization processes associated with the flameless AAS method, and the need to run frequent QC samples when performing automated analysis.
5.1.3 Sample Collection and Handling
Sample collection procedures are addressed primarily to identify ways to minimize the degree of variability that may be introduced by sample collection during medical monitoring. It is unclear at this point the extent to which collection procedures contribute to variability among CDB samples. Sources of variation that may result from sampling procedures include time-of-day effects and introduction of external contamination during the collection process. To minimize these sources, strict adherence to a sample collection protocol is recommended. Such a protocol must include provisions for thorough cleaning of the site from which blood will be extracted; also, every effort should be made to collect samples near the same time of day. It is also important to recognize that under the recent OSHA blood-borne pathogens standard (29 CFR 1910.1030), blood samples and certain body fluids must be handled and treated as if they are infectious.
5.1.4 Best Achievable Performance
The best achievable performance using a particular method for CDB determinations is assumed to be equivalent to the performance reported by research laboratories in which the method was developed.
For their method, Roberts and Clark (1986) demonstrated a limit of detection of 0.4 µg Cd/l in whole blood, with a linear response curve from 0.4 to 16.0 µg Cd/l. They report a coefficient of variation (CV) of 6.7% at 8.0 µg/l.
The APHA (1988) reports a range of 1.0-25 µg/l, with a CV of 7.3% (concentration not stated). Insufficient documentation was available to critique this method.
Stoeppler and Brandt (1980) achieved a detection limit of 0.2 µg Cd/l whole blood, with a linear range of 0.4-12.0 µg Cd/l, and a CV of 15-30%, for samples at <1.0 µg/l. Improved precision (CV of 3.8%) was reported for CDB concentrations at 9.3 µg/l.
5.1.5 General Method Performance
For any particular method, the performance expected from commercial laboratories may be somewhat lower than that reported by the research laboratory in which the method was developed. With participation in appropriate proficiency programs and use of a proper in-house QA/QC program incorporating provisions for regular corrective actions, the performance of commercial laboratories is expected to approach that reported by research laboratories. Also, the results reported for existing proficiency programs serve as a gauge of the likely level of performance that currently can be expected from commercial laboratories offering these analyses.
Weber (1988) reports on the results of the proficiency program run by the Centre de Toxicologie du Quebec (CTQ). As indicated previously, participants in that program receive 18 blood samples per year having cadmium concentrations ranging from 0.2-20 µg/l. Currently, 76 laboratories are participating in this program. The program is established for several analytes in addition to cadmium, and not all of these laboratories participate in the cadmium proficiency-testing program.
Under the CTQ program, cadmium results from individual laboratories are compared against the consensus mean derived for each sample. Results indicate that after receiving 60 samples ( i.e., after participation for approximately three years), 60% of the laboratories in the program are able to report results that fall within ±1 µg/l or 15% of the mean, whichever is greater. (For this procedure, the 15% criterion was applied to concentrations exceeding 7 µg/l.) On any single sample of the last 20 samples, the percentage of laboratories falling within the specified range is between 55 and 80%.
The CTQ also evaluates the performance of participating laboratories against a less severe standard: ±2 µg/l or 15% of the mean, whichever is greater (Weber 1988); 90% of participating laboratories are able to satisfy this standard after approximately 3 years in the program. (The 15% criterion is used for concentrations in excess of 13 µg/l.) On any single sample of the last 15 samples, the percentage of laboratories falling within the specified range is between 80 and 95% (except for a single test for which only 60% of the laboratories achieved the desired performance).
Based on the data presented in Weber (1988), the CV for analysis of CDB is nearly constant at 20% for cadmium concentrations exceeding 5 µg/l, and increases for cadmium concentrations below 5 µg/l. At 2 µg/l, the reported CV rises to approximately 40%. At 1 µg/l, the reported CV is approximately 60%.
Participating laboratories also tend to overestimate concentrations for samples exhibiting concentrations less than 2 µg/l (see Figure 11 of Weber 1988). This problem is due in part to the proficiency evaluation criterion that allows reporting a minimum ±2.0 µg/l for evaluated CDB samples. There is currently little economic or regulatory incentive for laboratories participating in the CTQ program to achieve greater accuracy for CDB samples containing cadmium at concentrations less than 2.0 µg/l, even if the laboratory has the experience and competency to distinguish among lower concentrations in the samples obtained from the CTQ.
The collective experience of international agencies and investigators demonstrate the need for a vigorous QC program to ensure that CDB values reported by participating laboratories are indeed reasonably accurate. As Friberg (1988) stated:
“Information about the quality of published data has often been lacking. This is of concern as assessment of metals in trace concentrations in biological media are fraught with difficulties from the collection, handling, and storage of samples to the chemical analyses. This has been proven over and over again from the results of interlaboratory testing and quality control exercises. Large variations in results were reported even from ‘experienced’ laboratories.”
The UNEP/WHO global study of cadmium biological monitoring set a limit for CDB accuracy using the maximum allowable deviation method at Y = X±(0.1X + 1) for a targeted concentration of 10 µg Cd/l (Friberg and Vahter 1983). The performance of participating laboratories over a concentration range of 1.5-12 µg/l was reported by Lind et al. (1987). Of the 3 QC runs conducted during 1982 and 1983, 1 or 2 of the 6 laboratories failed each run. For the years 1983 and 1985, between zero and 2 laboratories failed each of the consecutive QC runs.
In another study (Vahter and Friberg 1988), QC samples consisting of both external (unknown) and internal (stated) concentrations were distributed to laboratories participating in the epidemiology research. In this study, the maximum acceptable deviation between the regression analysis of reported results and reference values was set at Y = X±(0.05X + 0.2) for a concentration range of 0.3-5.0 µg Cd/l. It is reported that only 2 of 5 laboratories had acceptable data after the first QC set, and only 1 of 5 laboratories had acceptable data after the second QC set. By the fourth QC set, however, all 5 laboratories were judged proficient.
The need for high quality CDB monitoring is apparent when the toxicological and biological characteristics of this metal are considered; an increase in CDB from 2 to 4 µg/l could cause a doubling of the cadmium accumulation in the kidney, a critical target tissue for selective cadmium accumulation (Nordberg and Nordberg 1988).
Historically, the CDC's internal QC program for CDB cadmium monitoring program has found achievable accuracy to be ±10% of the true value at CDB concentrations ≥5.0 µg/l (Paschal 1990). Data on the performance of laboratories participating in this program currently are not available.
5.1.6 Observed CDB Concentrations
As stated in Section 4.3, CDB concentrations are representative of ongoing levels of exposure to cadmium. Among those who have been exposed chronically to cadmium for extended periods, however, CDB may contain a component attributable to the general cadmium body burden.
5.1.6.1 CDB Concentrations Among Unexposed Samples
Numerous studies have been conducted examining CDB concentrations in the general population, and in control groups used for comparison with cadmium-exposed workers. A number of reports have been published that present erroneously high values of CDB (Nordberg and Nordberg 1988). This problem was due to contamination of samples during sampling and analysis, and to errors in analysis. Early AAS methods were not sufficiently sensitive to accurately estimate CDB concentrations.
| Study No. | No. in study (n) | Sex | Age | Smoking habits b | Arithmetic mean (±S.D.) c | Absolute range or (95% CI) d | Geometric mean (±GSD) e | Lower 95th percentile of distribution f | Upper 95th percentile of distribution f | Reference |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 80 | M | 4 to 69 | NS,S | 1.13 | 0.35-3.3 | 0.98±1.71 | 0.4 | 2.4 | Kowal et al. (1979). |
| 88 | F | 4 to 69 | NS,S | 1.03 | 0.21-3.3 | 0.91±1.63 | 0.4 | 2.0 | ||
| 115 | M/F | 4 to 69 | NS | 0.95 | 0.21-3.3 | 0.85±1.59 | 0.4 | 1.8 | ||
| 31 | M/F | 4 to 69 | S | 1.54 | 0.4-3.3 | 1.37±1.65 | 0.6 | 3.2 | ||
| 2 | 10 | M | Adults | (?) | 2.0±2.1 | (0.5-5.0) | g (0) | g (5.8) | Ellis et al. (1983). | |
| 3 | 24 | M | Adults | NS | 0.6±1/87 | 0.2 | 1.8 | Frieberg and Vahter (1983). | ||
| 20 | M | Adults | S | 1.2±2.13 | 0.3 | 4.4 | ||||
| 64 | F | Adults | NS | 0.5±1.85 | 0.2 | 1.4 | ||||
| 39 | F | Adults | S | 0.8±2.22 | 0.2 | 3.1 | ||||
| 4 | 32 | M | Adults | S,NS | 1.2±2.0 | 0.4 | 3.9 | Thun et al. (1989). | ||
| 5 | 35 | M | Adults | (?) | 2.1±2.1 | (0.5-7.3) | g (0) | g (5.6) | Mueller et al. (1989). | |
| a Concentrations reported in µg Cd/l blood unless otherwise stated. | ||||||||||
| b NS—never smoked; S—current cigarette smoker. | ||||||||||
| c S.D.—Arithmetic Standard Deviation. | ||||||||||
| d C.I.—Confidence interval. | ||||||||||
| e GSD—Geometric Standard Deviation. | ||||||||||
| f Based on an assumed lognormal distribution. | ||||||||||
| g Based on an assumed normal distribution. |
Arithmetic and/or geometric means and standard deviations are provided in Table 4 for measurements among the populations defined in each study listed. The range of reported measurements and/or the 95% upper and lower confidence intervals for the means are presented when this information was reported in a study. For studies reporting either an arithmetic or geometric standard deviation along with a mean, the lower and upper 95th percentile for the distribution also were derived and reported in the table.
The data provided in table 4 from Kowal et al. (1979) are from studies conducted between 1974 and 1976 evaluating CDB levels for the general population in Chicago, and are considered to be representative of the U.S. population. These studies indicate that the average CDB concentration among those not occupationally exposed to cadmium is approximately 1 µg/l.
In several other studies presented in Table 4, measurements are reported separately for males and females, and for smokers and nonsmokers. The data in this table indicate that similar CDB levels are observed among males and females in the general population, but that smokers tend to exhibit higher CDB levels than nonsmokers. Based on the Kowal et al. (1979) study, smokers not occupationally exposed to cadmium exhibit an average CDB level of 1.4 µg/l.
In general, nonsmokers tend to exhibit levels ranging to 2 µg/l, while levels observed among smokers range to 5 µg/l. Based on the data presented in Table 4, 95% of those not occupationally exposed to cadmium exhibit CDB levels less than 5 µg/l.
5.1.6.2 CDB concentrations among exposed workers
CDB levels reported in table 5 are higher among those showing signs of cadmium-related kidney damage than those showing no such damage. Lauwerys et al. (1976) report CDB levels among workers with kidney lesions that generally are above the levels reported for workers without kidney lesions. Ellis et al. (1983) report a similar observation comparing workers with and without renal dysfunction, although they found more overlap between the 2 groups than Lauwerys et al.
| Study number | Work environment (worker population monitored) | Number in study | Employment in years (mean) | Mean concentration of cadmium in air (µg/m 3 ) | Concentrations of Cadmium in blood a | ||
|---|---|---|---|---|---|---|---|
| Arithmetic mean (±S.D.) b | Absolute range or (95% C.I.) c | Geometric mean (GSD) d | Lower 95th percentile of range e ( ) f | Upper 95th percentile of range e ( ) f | Reference | ||
| 1 | Ni-Cd battery plant and Cd production plant: | 3-40 | ≤90 | Lauwerys et al. 1976. | |||
| (Workers without kidney lesions) | 96 | 21.4±1.9 | (18) | (25) | |||
| (Workers with kidney lesions) | 25 | 38.8±3.8 | (32) | (45) | |||
| 2 | Ni-Cd battery plant: | Adamsson et al. (1979). | |||||
| (Smokers) | 7 | (5) | 10.1 | 22.7 | 7.3-67.2 | ||
| (Nonsmokers) | 8 | (9) | 7.0 | 7.0 | 4.9-10.5 | ||
| 3 | Cadmium alloy plant: | Sukuri et al. 1982. | |||||
| (High exposure group) | 7 | (10.6) | [1,000-5 yrs; | 20.8±7.1 | (7.3) | (34) | |
| (Low exposure group) | 9 | (7.3) | 40-5 yrs] | 7.1±1.1 | (5.1) | (9.1) | |
| 4 | Retrospective study of workers with renal problems: | 19 | 15-41 | Roels et al. 1982. | |||
| (Before removal) | (27.2) | 39.9±3.7 | 11-179 | (34) | (46) | ||
| (After removal) | g (4.2) | 14.1±5.6 | 5.7-27.4 | (4.4) | (24) | ||
| 5 | Cadmium production plant: | Ellis et al. 1983. | |||||
| (Workers without renal dysfunction) | 33 | 1-34 | 15±5.7 | 7-31 | (5.4) | (25) | |
| (Workers with renal dysfunction) | 18 | 10-34 | 24±8.5 | 10-34 | (9.3) | (39) | |
| 6 | Cd-Cu alloy plant | 75 | Up to 39 | 8.8±1.1 | 7.5 | 10 | Mason et al. 1988. |
| 7 | Cadmium recovery operation—Current (19) and former (26) workers | 45 | (19.0) | 7.9±2.0 | 2.5 | 25 | Thun et al. 1989. |
| 8 | Cadmium recovery operation | 40 | 10.2±5.3 | 2.2-18.8 | (1.3) | (19) | Mueller et al. 1989. |
| a Concentrations reported in µg Cd/l blood unless otherwise stated. | |||||||
| b S.D.—Standard Deviation. | |||||||
| c C.I.—Confidence Interval. | |||||||
| d GSD—Geometric Standard Deviation. | |||||||
| e Based on an assumed lognormal distribution. | |||||||
| f Based on an assumed normal distribution. | |||||||
| g Years following removal. |
The data in table 5 also indicate that CDB levels are higher among those experiencing current occupational exposure than those who have been removed from such exposure. Roels et al. (1982) indicate that CDB levels observed among workers experiencing ongoing exposure in the work place are almost entirely above levels observed among workers removed from such exposure. This finding suggests that CDB levels decrease once cadmium exposure has ceased.
A comparison of the data presented in tables 4 and 5 indicates that CDB levels observed among cadmium-exposed workers is significantly higher than levels observed among the unexposed groups. With the exception of 2 studies presented in table 5 (1 of which includes former workers in the sample group tested), the lower 95th percentile for CDB levels among exposed workers are greater than 5 µg/l, which is the value of the upper 95th percentile for CDB levels observed among those who are not occupationally exposed. Therefore, a CDB level of 5 µg/l represents a threshold above which significant work place exposure to cadmium may be occurring.
5.1.7 Conclusions and Recommendations for CDB
Based on the above evaluation, the following recommendations are made for a CDB proficiency program.
5.1.7.1 Recommended method
The method of Stoeppler and Brandt (1980) should be adopted for analyzing CDB. This method was selected over other methods for its straightforward sample-preparation procedures, and because limitations of the method were described adequately. It also is the method used by a plurality of laboratories currently participating in the CTQ proficiency program. In a recent CTQ interlaboratory comparison report (CTQ 1991), analysis of the methods used by laboratories to measure CDB indicates that 46% (11 of 24) of the participating laboratories used the Stoeppler and Brandt methodology (HNO 3 deproteinization of blood followed by analysis of the supernatant by GF-AAS). Other CDB methods employed by participating laboratories identified in the CTQ report include dilution of blood (29%), acid digestion (12%) and miscellaneous methods (12%).
Laboratories may adopt alternate methods, but it is the responsibility of the laboratory to demonstrate that the alternate methods meet the data quality objectives defined for the Stoeppler and Brandt method (see Section 5.1.7.2 below).
5.1.7.2 Data quality objectives
Based on the above evaluation, the following data quality objectives (DQOs) should facilitate interpretation of analytical results.
Limit of Detection. 0.5 µg/l should be achievable using the Stoeppler and Brandt method. Stoeppler and Brandt (1980) report a limit of detection equivalent to ≤0.2 µg/l in whole blood using 25 µl aliquots of deproteinized, diluted blood samples.
Accuracy. Initially, some of the laboratories performing CDB measurements may be expected to satisfy criteria similar to the less severe criteria specified by the CTQ program, i.e., measurements within 2 µg/l or 15% (whichever is greater) of the target value. About 60% of the laboratories enrolled in the CTQ program could meet this criterion on the first proficiency test (Weber 1988).
Currently, approximately 12 laboratories in the CTQ program are achieving an accuracy for CDB analysis within the more severe constraints of ±1 µg/l or 15% (whichever is greater). Later, as laboratories gain experience, they should achieve the level of accuracy exhibited by these 12 laboratories. The experience in the CTQ program has shown that, even without incentives, laboratories benefit from the feedback of the program; after they have analyzed 40-50 control samples from the program, performance improves to the point where about 60% of the laboratories can meet the stricter criterion of ±1 µg/l or 15% (Weber 1988). Thus, this stricter target accuracy is a reasonable DQO.
Precision. Although Stoeppler and Brandt (1980) suggest that a coefficient of variation (CV) near 1.3% (for a 10 µg/l concentration) is achievable for within-run reproducibility, it is recognized that other factors affecting within- and between-run comparability will increase the achievable CV. Stoeppler and Brandt (1980) observed CVs that were as high as 30% for low concentrations (0.4 µg/l), and CVs of less than 5% for higher concentrations.
For internal QC samples (see Section 3.3.1), laboratories should attain an overall precision near 25%. For CDB samples with concentrations less than 2 µg/l, a target precision of 40% is reasonable, while precisions of 20% should be achievable for concentrations greater than 2 µg/l. Although these values are more strict than values observed in the CTQ interlaboratory program reported by Webber (1988), they are within the achievable limits reported by Stoeppler and Brandt (1980).
5.1.7.3 Quality assurance/quality control
Commercial laboratories providing measurement of CDB should adopt an internal QA/QC program that incorporates the following components: Strict adherence to the selected method, including all calibration requirements; regular incorporation of QC samples during actual runs; a protocol for corrective actions, and documentation of these actions; and, participation in an interlaboratory proficiency program. Note that the nonmandatory QA/QC program presented in Attachment 1 is based on the Stoeppler and Brandt method for CDB analysis. Should an alternate method be adopted, the laboratory should develop a QA/QC program satisfying the provisions of Section 3.3.1.
5.2 Measuring Cadmium in Urine (CDU)
As in the case of CDB measurement, proper determination of CDU requires strict analytical discipline regarding collection and handling of samples. Because cadmium is both ubiquitous in the environment and employed widely in coloring agents for industrial products that may be used during sample collection, preparation and analysis, care should be exercised to ensure that samples are not contaminated during the sampling procedure.
Methods for CDU determination share many of the same features as those employed for the determination of CDB. Thus, changes and improvements to methods for measuring CDU over the past 40 years parallel those used to monitor CDB. The direction of development has largely been toward the simplification of sample preparation techniques made possible because of improvements in analytic techniques.
5.2.1 Units of CDU Measurement
Procedures adopted for reporting CDU concentrations are not uniform. In fact, the situation for reporting CDU is more complicated than for CDB, where concentrations are normalized against a unit volume of whole blood.
Concentrations of solutes in urine vary with several biological factors (including the time since last voiding and the volume of liquid consumed over the last few hours); as a result, solute concentrations should be normalized against another characteristic of urine that represents changes in solute concentrations. The 2 most common techniques are either to standardize solute concentrations against the concentration of creatinine, or to standardize solute concentrations against the specific gravity of the urine. Thus, CDU concentrations have been reported in the literature as “uncorrected” concentrations of cadmium per volume of urine ( i.e., µg Cd/l urine), “corrected” concentrations of cadmium per volume of urine at a standard specific gravity ( i.e., µg Cd/l urine at a specific gravity of 1.020), or “corrected” mass concentration per unit mass of creatinine ( i.e., µg Cd/g creatinine). (CDU concentrations [whether uncorrected or corrected for specific gravity, or normalized to creatinine] occasionally are reported in nanomoles [ i.e., nmoles] of cadmium per unit mass or volume. In this protocol, these values are converted to µg of cadmium per unit mass or volume using 89 nmoles of cadmium = 10 µg.)
While it is agreed generally that urine values of analytes should be normalized for reporting purposes, some debate exists over what correction method should be used. The medical community has long favored normalization based on creatinine concentration, a common urinary constituent. Creatinine is a normal product of tissue catabolism, is excreted at a uniform rate, and the total amount excreted per day is constant on a day-to-day basis (NIOSH 1984b). While this correction method is accepted widely in Europe, and within some occupational health circles, Kowals (1983) argues that the use of specific gravity ( i.e., total solids per unit volume) is more straightforward and practical (than creatinine) in adjusting CDU values for populations that vary by age or gender.
Kowals (1983) found that urinary creatinine (CRTU) is lower in females than males, and also varies with age. Creatinine excretion is highest in younger males (20-30 years old), decreases at middle age (50-60 years), and may rise slightly in later years. Thus, cadmium concentrations may be underestimated for some workers with high CRTU levels.
Within a single void urine collection, urine concentration of any analyte will be affected by recent consumption of large volumes of liquids, and by heavy physical labor in hot environments. The absolute amount of analyte excreted may be identical, but concentrations will vary widely so that urine must be corrected for specific gravity ( i.e., to normalize concentrations to the quantity of total solute) using a fixed value (e.g., 1.020 or 1.024). However, since heavy-metal exposure may increase urinary protein excretion, there is a tendency to underestimate cadmium concentrations in samples with high specific gravities when specific-gravity corrections are applied.
Despite some shortcomings, reporting solute concentrations as a function of creatinine concentration is accepted generally; OSHA therefore recommends that CDU levels be reported as the mass of cadmium per unit mass of creatinine (µg/g CTRU).
Reporting CDU as µg/g CRTU requires an additional analytical process beyond the analysis of cadmium: Samples must be analyzed independently for creatinine so that results may be reported as the ratio of cadmium to creatinine concentrations found in the urine sample. Consequently, the overall quality of the analysis depends on the combined performance by a laboratory on these 2 determinations. The analysis used for CDU determinations is addressed below in terms of µg Cd/l, with analysis of creatinine addressed separately. Techniques for assessing creatinine are discussed in Section 5.4.
Techniques for deriving cadmium as a ratio of CRTU, and the confidence limits for independent measurements of cadmium and CRTU, are provided in Section 3.3.3.
5.2.2 Analytical Techniques Used To Monitor CDU
Analytical techniques used for CDU determinations are similar to those employed for CDB determinations; these techniques are summarized in Table 3. As with CDB monitoring, the technique most suitable for CDU determinations is atomic absorption spectroscopy (AAS). AAS methods used for CDU determinations typically employ a graphite furnace, with background correction made using either the deuterium-lamp or Zeeman techniques; Section 5.1.1 provides a detailed description of AAS methods.
5.2.3 Methods Developed for CDU Determinations
Princi (1947), Smith et al. (1955), Smith and Kench (1957), and Tsuchiya (1967) used colorimetric procedures similar to those described in the CDB section above to estimate CDU concentrations. In these methods, urine (50 ml) is reduced to dryness by heating in a sand bath and digested (wet ashed) with mineral acids. Cadmium then is complexed with dithiazone, extracted with chloroform and quantified by spectrophotometry. These early studies typically report reagent blank values equivalent to 0.3 µg Cd/l, and CDU concentrations among nonexposed control groups at maximum levels of 10 µg Cd/l—erroneously high values when compared to more recent surveys of cadmium concentrations in the general population.
By the mid-1970s, most analytical procedures for CDU analysis used either wet ashing (mineral acid) or high temperatures (>400 °C) to digest the organic matrix of urine, followed by cadmium chelation with APDC or DDTC solutions and extraction with MIBK. The resulting aliquots were analyzed by flame or graphite-furnace AAS (Kjellstrom 1979).
Improvements in control over temperature parameters with electrothermal heating devices used in conjunction with flameless AAS techniques, and optimization of temperature programs for controlling the drying, charring, and atomization processes in sample analyses, led to improved analytical detection of diluted urine samples without the need for sample digestion or ashing. Roels et al. (1978) successfully used a simple sample preparation, dilution of 1.0 ml aliquots of urine with 0.1 N HNO 3, to achieve accurate low-level determinations of CDU.
In the method described by Pruszkowska et al. (1983), which has become the preferred method for CDU analysis, urine samples were diluted at a ratio of 1:5 with water; diammonium hydrogenphosphate in dilute HNO 3 was used as a matrix modifier. The matrix modifier allows for a higher charring temperature without loss of cadmium through volatilization during preatomization. This procedure also employs a stabilized temperature platform in a graphite furnace, while nonspecific background absorbtion is corrected using the Zeeman technique. This method allows for an absolute detection limit of approximately 0.04 µg Cd/l urine.
5.2.4 Sample Collection and Handling
Sample collection procedures for CDU may contribute to variability observed among CDU measurements. Sources of variation attendant to sampling include time-of-day, the interval since ingestion of liquids, and the introduction of external contamination during the collection process. Therefore, to minimize contributions from these variables, strict adherence to a sample-collection protocol is recommended. This protocol should include provisions for normalizing the conditions under which urine is collected. Every effort also should be made to collect samples during the same time of day.
Collection of urine samples from an industrial work force for biological monitoring purposes usually is performed using “spot” ( i.e., single-void) urine with the pH of the sample determined immediately. Logistic and sample-integrity problems arise when efforts are made to collect urine over long periods (e.g., 24 hrs). Unless single-void urines are used, there are numerous opportunities for measurement error because of poor control over sample collection, storage and environmental contamination.
To minimize the interval during which sample urine resides in the bladder, the following adaption to the “spot” collection procedure is recommended: The bladder should first be emptied, and then a large glass of water should be consumed; the sample may be collected within an hour after the water is consumed.
5.2.5 Best Achievable Performance
Performance using a particular method for CDU determinations is assumed to be equivalent to the performance reported by the research laboratories in which the method was developed. Pruszkowska et al. (1983) report a detection limit of 0.04 µg/l CDU, with a CV of <4% between 0-5 µg/l. The CDC reports a minimum CDU detection limit of 0.07 µg/l using a modified method based on Pruszkowska et al. (1983). No CV is stated in this protocol; the protocol contains only rejection criteria for internal QC parameters used during accuracy determinations with known standards (Attachment 8 of exhibit 106 of OSHA docket H057A). Stoeppler and Brandt (1980) report a CDU detection limit of 0.2 µ/l for their methodology.
5.2.6 General Method Performance
For any particular method, the expected initial performance from commercial laboratories may be somewhat lower than that reported by the research laboratory in which the method was developed. With participation in appropriate proficiency programs, and use of a proper in-house QA/QC program incorporating provisions for regular corrective actions, the performance of commercial laboratories may be expected to improve and approach that reported by a research laboratories. The results reported for existing proficiency programs serve to specify the initial level of performance that likely can be expected from commercial laboratories offering analysis using a particular method.
Weber (1988) reports on the results of the CTQ proficiency program, which includes CDU results for laboratories participating in the program. Results indicate that after receiving 60 samples ( i.e., after participating in the program for approximately 3 years), approximately 80% of the participating laboratories report CDU results ranging between ±2 µg/l or 15% of the consensus mean, whichever is greater. On any single sample of the last 15 samples, the proportion of laboratories falling within the specified range is between 75 and 95%, except for a single test for which only 60% of the laboratories reported acceptable results. For each of the last 15 samples, approximately 60% of the laboratories reported results within ±1 µg or 15% of the mean, whichever is greater. The range of concentrations included in this set of samples was not reported.
Another report from the CTQ (1991) summarizes preliminary CDU results from their 1991 interlaboratory program. According to the report, for 3 CDU samples with values of 9.0, 16.8, 31.5 µg/l, acceptable results (target of ±2 µg/l or 15 % of the consensus mean, whichever is greater) were achieved by only 44-52% of the 34 laboratories participating in the CDU program. The overall CVs for these 3 CDU samples among the 34 participating laboratories were 31%, 25%, and 49%, respectively. The reason for this poor performance has not been determined.
A more recent report from the CTQ (Weber, private communication) indicates that 36% of the laboratories in the program have been able to achieve the target of ±1 µg/l or 15% for more than 75% of the samples analyzed over the last 5 years, while 45% of participating laboratories achieved a target of ±2 µg/l or 15% for more than 75% of the samples analyzed over the same period.
Note that results reported in the interlaboratory programs are in terms of µg Cd/l of urine, unadjusted for creatinine. The performance indicated, therefore, is a measure of the performance of the cadmium portion of the analyses, and does not include variation that may be introduced during the analysis of CRTU.
5.2.7 Observed CDU Concentrations
Prior to the onset of renal dysfunction, CDU concentrations provide a general indication of the exposure history ( i.e., body burden) (see Section 4.3). Once renal dysfunction occurs, CDU levels appear to increase and are no longer indicative solely of cadmium body burden (Friberg and Elinder 1988).
5.2.7.1 Range of CDU concentrations observed among unexposed samples
Surveys of CDU concentrations in the general population were first reported from cooperative studies among industrial countries ( i.e., Japan, U.S. and Sweden) conducted in the mid-1970s. In summarizing these data, Kjellstrom (1979) reported that CDU concentrations among Dallas, Texas men (age range: <9-59 years; smokers and nonsmokers) varied from 0.11-1.12 µg/l (uncorrected for creatinine or specific gravity). These CDU concentrations are intermediate between population values found in Sweden (range: 0.11-0.80 µg/l) and Japan (range: 0.14-2.32 µg/l).
Kowal and Zirkes (1983) reported CDU concentrations for almost 1,000 samples collected during 1978-79 from the general U.S. adult population ( i.e., nine states; both genders; ages 20-74 years). They report that CDU concentrations are lognormally distributed; low levels predominated, but a small proportion of the population exhibited high levels. These investigators transformed the CDU concentrations values, and reported the same data 3 different ways: µg/l urine (unadjusted), µg/l (specific gravity adjusted to 1.020), and µg/g CRTU. These data are summarized in Tables 6 and 7.
Based on further statistical examination of these data, including the lifestyle characteristics of this group, Kowal (1988) suggested increased cadmium absorption ( i.e., body burden) was correlated with low dietary intakes of calcium and iron, as well as cigarette smoking.
CDU levels presented in Table 6 are adjusted for age and gender. Results suggest that CDU levels may be slightly different among men and women ( i.e., higher among men when values are unadjusted, but lower among men when the values are adjusted, for specific gravity or CRTU). Mean differences among men and women are small compared to the standard deviations, and therefore may not be significant. Levels of CDU also appear to increase with age. The data in Table 6 suggest as well that reporting CDU levels adjusted for specific gravity or as a function of CRTU results in reduced variability.
| Geometric means (and geometric standard deviations) | |||
|---|---|---|---|
| Unadjusted (µg/l) | SG-adjusted 2 µg/l at 1.020) | Creatine-adjusted (µg/g) | |
| Sex: | |||
| Male (n = 484) | 0.55 (2.9) | 0.73 (2.6) | 0.55 (2.7) |
| Female (n = 498) | 0.49 (3.0) | 0.86 (2.7) | 0.78 (2.7) |
| Age: | |||
| 20-29 (n = 222) | 0.32 (3.0) | 0.43 (2.7) | 0.32 (2.7) |
| 30-39 (n = 141) | 0.46 (3.2) | 0.70 (2.8) | 0.54 (2.7) |
| 40-49 (n = 142) | 0.50 (3.0) | 0.81 (2.6) | 0.70 (2.7) |
| 50-59 (n = 117) | 0.61 (2.9) | 0.99 (2.4) | 0.90 (2.3) |
| 60-69 (n = 272) | 0.76 (2.6) | 1.16 (2.3) | 1.03 (2.3) |
| 1 From Kowal and Zirkes 1983. | |||
| 2 SC-adjusted is adjusted for specific gravity. |
| Range of concentrations | Unadjusted (µg/l) percent | SG-adjusted (µg/l at 1.020) percent | Creatine-adjusted (µg/g) percent |
|---|---|---|---|
| <0.5 | 43.9 | 28.0 | 35.8 |
| 0.6-1.0 | 71.7 | 56.4 | 65.6 |
| 1.1-1.5 | 84.4 | 74.9 | 81.4 |
| 1.6-2.0 | 91.3 | 84.7 | 88.9 |
| 2.1-3.0 | 97.3 | 94.4 | 95.8 |
| 3.1-4.0 | 98.8 | 97.4 | 97.2 |
| 4.1-5.0 | 99.4 | 98.2 | 97.9 |
| 5.1-10.0 | 99.6 | 99.4 | 99.3 |
| 10.0-20.0 | 99.8 | 99.6 | 99.6 |
| 1 Source: Kowal and Zirkes (1983). |
The data in the Table 6 indicate the geometric mean of CDU levels observed among the general population is 0.52 µ/g Cd/l urine (unadjusted), with a geometric standard deviation of 3.0. Normalized for creatinine, the geometric mean for the population is 0.66 µ/g CRTU, with a geometric standard deviation of 2.7. Table 7 provides the distributions of CDU concentrations for the general population studied by Kowal and Zirkes. The data in this table indicate that 95% of the CDU levels observed among those not occupationally exposed to cadmium are below 3 µ/g CRTU.
5.2.7.2 Range of CDU concentrations observed among exposed workers
| Study number | Work environment (worker population monitored) | Number in Study (n) | Employment in years (mean) | Mean Concentration of cadmium in air (µg/m 3 ) | Concentration of cadmium in Urine a | |||
|---|---|---|---|---|---|---|---|---|
| Arithmetic mean (±S.D.) b | Absolute range or (95% C.I.) c | Geometric mean (GSD) d | Lower 95th percentile of range e ( ) f | Upper 95th percentile of range e ( ) f | Reference | |||
| 1 | Ni-Cd battery plant and Cd production plant | 3-40 | ≤90 | Lauwerys et al. 1976. | ||||
| (Workers without kidney lesions) | 96 | 16.3±16.7 | (0) | (44) | ||||
| (Workers with kidney lesions) | 25 | 48.2±42.6 | (0) | (120) | ||||
| 2 | Ni-Cd battery plant | Adamsson et al. (1979). | ||||||
| (Smokers) | 7 | (5) | 10.1 | 5.5 | 1.0-14.7 | |||
| (Nonsmokers) | 8 | (9) | 7.0 | 3.6 | 0.5-9.3 | |||
| 3 | Cadmium salts production facility | 148 | (15.4) | 15.8 | 2-150 | Butchet et al. 1980. | ||
| 4 | Retrospective study of workers with renal problems | 19 | 15-41 | Roels et al. 1982. | ||||
| (Before removal) | (27.2) | 39.4±28.1 | 10.8-117 | (0) | (88) | |||
| (After removal) | (4.2) g | 16.4±9.0 | 80-42.3 | (1.0) | (32) | |||
| 5 | Cadmium production plant | Ellis et al. 1983. | ||||||
| (Workers without renal dysfunction) | 33 | 1-34 | 9.4±6.9 | 2-27 | (0) | (21) | ||
| (Workers with renal dysfunction) | 18 | 10-34 | 22.8±12.7 | 8-55 | (1) | (45) | ||
| 6 | Cd-Cu alloy plant | 75 | Up to 39 | Note h | 6.9±9.4 | (0) | (23) | Mason et al. 1988. |
| 7 | Cadmium recovery operation | 45 | (19) | 87 | 9.3±6.9 | (0) | (21) | Thun et al. 1989. |
| 8 | Pigment manufacturing plant | 29 | (12.8) | 0.18-3.0 | 0.2-9.5 | 1.1 | Mueller et al. 1989. | |
| 9 | Pigment manufacturing plant | 26 | (12.1) | ≤3.0 | 1.25±2.45 | 0.3 | 6 | Kawada et al. 1990. |
| a Concentrations reported in µg/g Cr. | ||||||||
| b S.D.—Standard Deviation. | ||||||||
| c C.I.—Confidence Interval. | ||||||||
| d GSD—Geometric Standard Deviation. | ||||||||
| e Based on an assumed lognormal distribution. | ||||||||
| f Based on an assumed normal distribution. | ||||||||
| g Years following removal. | ||||||||
| h Equivalent to 50 for 20-22 yrs |
Data in Table 8 from Lauwerys et al. (1976) and Ellis et al. (1983) indicate that CDU concentrations are higher among those exhibiting kidney lesions or dysfunction than among those lacking these symptoms. Data from the study by Roels et al. (1982) indicate that CDU levels decrease among workers removed from occupational exposure to cadmium in comparison to workers experiencing ongoing exposure. In both cases, however, the distinction between the 2 groups is not as clear as with CDB; there is more overlap in CDU levels observed among each of the paired populations than is true for corresponding CDB levels. As with CDB levels, the data in Table 8 suggest increased CDU concentrations among workers who experienced increased overall exposure.
Although a few occupationally-exposed workers in the studies presented in Table 8 exhibit CDU levels below 3 µg/g CRTU, most of those workers exposed to cadmium levels in excess of the PEL defined in the final cadmium rule exhibit CDU levels above 3 µg/g CRTU; this level represents the upper 95th percentile of the CDU distribution observed among those who are not occupationally exposed to cadmium (Table 7).
The mean CDU levels reported in Table 8 among occupationally-exposed groups studied (except 2) exceed 3 µg/g CRTU. Correspondingly, the level of exposure reported in these studies (with 1 exception) are significantly higher than what workers will experience under the final cadmium rule. The 2 exceptions are from the studies by Mueller et al. (1989) and Kawada et al. (1990); these studies indicate that workers exposed to cadmium during pigment manufacture do not exhibit CDU levels as high as those levels observed among workers exposed to cadmium in other occupations. Exposure levels, however, were lower in the pigment manufacturing plants studied. Significantly, workers removed from occupational cadmium exposure for an average of 4 years still exhibited CDU levels in excess of 3 µg/g CRTU (Roels et al. 1982). In the single-exception study with a reported level of cadmium exposure lower than levels proposed in the final rule ( i.e., the study of a pigment manufacturing plant by Kawada et al. 1990), most of the workers exhibited CDU levels less than 3 µg/g CRTU ( i.e., the mean value was only 1.3 µg/g CRTU). CDU levels among workers with such limited cadmium exposure are expected to be significantly lower than levels of other studies reported in Table 8.
Based on the above data, a CDU level of 3 µg/g CRTU appear to represent a threshold above which significant work place exposure to cadmium occurs over the work span of those being monitored. Note that this threshold is not as distinct as the corresponding threshold described for CDB. In general, the variability associated with CDU measurements among exposed workers appears to be higher than the variability associated with CDB measurements among similar workers.
5.2.8 Conclusions and Recommendations for CDU
The above evaluation supports the following recommendations for a CDU proficiency program. These recommendations address only sampling and analysis procedures for CDU determinations specifically, which are to be reported as an unadjusted µg Cd/l urine. Normalizing this result to creatinine requires a second analysis for CRTU so that the ratio of the 2 measurements can be obtained. Creatinine analysis is addressed in Section 5.4. Formal procedures for combining the 2 measurements to derive a value and a confidence limit for CDU in µg/g CRTU are provided in Section 3.3.3.
5.2.8.1 Recommended method
The method of Pruszkowska et al. (1983) should be adopted for CDU analysis. This method is recommended because it is simple, straightforward and reliable ( i.e., small variations in experimental conditions do not affect the analytical results).
A synopsis of the methods used by laboratories to determine CDU under the interlaboratory program administered by the CTQ (1991) indicates that more than 78% (24 of 31) of the participating laboratories use a dilution method to prepare urine samples for CDU analysis. Laboratories may adopt alternate methods, but it is the responsibility of the laboratory to demonstrate that the alternate methods provide results of comparable quality to the Pruszkowska method.
5.2.8.2 Data quality objectives
The following data quality objectives should facilitate interpretation of analytical results, and are achievable based on the above evaluation.
Limit of Detection. A level of 0.5 µg/l ( i.e., corresponding to a detection limit of 0.5 µg/g CRTU, assuming 1 g CRT/l urine) should be achievable. Pruszkowska et al. (1983) achieved a limit of detection of 0.04 µg/l for CDU based on the slope of the curve for their working standards (0.35 pg Cd/0.0044, A signal = 1% absorbance using GF-AAS).
The CDC reports a minimum detection limit for CDU of 0.07 µg/l using a modified Pruszkowska method. This limit of detection was defined as 3 times the standard deviation calculated from 10 repeated measurements of a “low level” CDU test sample (Attachment 8 of exhibit 106 of OSHA docket H057A).
Stoeppler and Brandt (1980) report a limit of detection for CDU of 0.2 µg/l using an aqueous dilution (1:2) of the urine samples.
Accuracy. A recent report from the CTQ (Weber, private communication) indicates that 36% of the laboratories in the program achieve the target of ±1 µg/l or 15% for more than 75% of the samples analyzed over the last 5 years, while 45% of participating laboratories achieve a target of ±2 µg/l or 15% for more than 75% of the samples analyzed over the same period. With time and a strong incentive for improvement, it is expected that the proportion of laboratories successfully achieving the stricter level of accuracy should increase. It should be noted, however, these indices of performance do not include variations resulting from the ancillary measurement of CRTU (which is recommended for the proper recording of results). The low cadmium levels expected to be measured indicate that the analysis of creatinine will contribute relatively little to the overall variability observed among creatinine-normalized CDU levels (see Section 5.4). The initial target value for reporting CDU under this program, therefore, is set at ±1 µg/g CRTU or 15% (whichever is greater).
Precision. For internal QC samples (which are recommended as part of an internal QA/QC program, Section 3.3.1), laboratories should attain an overall precision of 25%. For CDB samples with concentrations less than 2 µg/l, a target precision of 40% is acceptable, while precisions of 20% should be achievable for CDU concentrations greater than 2 µg/l. Although these values are more stringent than those observed in the CTQ interlaboratory program reported by Webber (1988), they are well within limits expected to be achievable for the method as reported by Stoeppler and Brandt (1980).
5.2.8.3 Quality assurance/quality control
Commercial laboratories providing CDU determinations should adopt an internal QA/QC program that incorporates the following components: Strict adherence to the selected method, including calibration requirements; regular incorporation of QC samples during actual runs; a protocol for corrective actions, and documentation of such actions; and, participation in an interlaboratory proficiency program. Note that the nonmandatory program presented in Attachment 1 as an example of an acceptable QA/QC program, is based on using the Pruszkowska method for CDU analysis. Should an alternate method be adopted by a laboratory, the laboratory should develop a QA/QC program equivalent to the nonmandatory program, and which satisfies the provisions of Section 3.3.1.
5.3 Monitoring β-2-Microglobulin in Urine (B2MU)
As indicated in Section 4.3, B2MU appears to be the best of several small proteins that may be monitored as early indicators of cadmium-induced renal damage. Several analytic techniques are available for measuring B2M.
5.3.1 Units of B2MU Measurement
Procedures adopted for reporting B2MU levels are not uniform. In these guidelines, OSHA recommends that B2MU levels be reported as µg/g CRTU, similar to reporting CDU concentrations. Reporting B2MU normalized to the concentration of CRTU requires an additional analytical process beyond the analysis of B2M: Independent analysis for creatinine so that results may be reported as a ratio of the B2M and creatinine concentrations found in the urine sample. Consequently, the overall quality of the analysis depends on the combined performance on these 2 analyses. The analysis used for B2MU determinations is described in terms of µg B2M/l urine, with analysis of creatinine addressed separately. Techniques used to measure creatinine are provided in Section 5.4. Note that Section 3.3.3 provides techniques for deriving the value of B2M as function of CRTU, and the confidence limits for independent measurements of B2M and CRTU.
5.3.2 Analytical Techniques Used To Monitor B2MU
One of the earliest tests used to measure B2MU was the radial immunodiffusion technique. This technique is a simple and specific method for identification and quantitation of a number of proteins found in human serum and other body fluids when the protein is not readily differentiated by standard electrophoretic procedures. A quantitative relationship exists between the concentration of a protein deposited in a well that is cut into a thin agarose layer containing the corresponding monospecific antiserum, and the distance that the resultant complex diffuses. The wells are filled with an unknown serum and the standard (or control), and incubated in a moist environment at room temperature. After the optimal point of diffusion has been reached, the diameters of the resulting precipition rings are measured. The diameter of a ring is related to the concentration of the constituent substance. For B2MU determinations required in the medical monitoring program, this method requires a process that may be insufficient to concentrate the protein to levels that are required for detection.
Radioimmunoassay (RIA) techniques are used widely in immunologic assays to measure the concentration of antigen or antibody in body-fluid samples. RIA procedures are based on competitive-binding techniques. If antigen concentration is being measured, the principle underlying the procedure is that radioactive-labeled antigen competes with the sample's unlabeled antigen for binding sites on a known amount of immobile antibody. When these 3 components are present in the system, an equilibrium exists. This equilibrium is followed by a separation of the free and bound forms of the antigen. Either free or bound radioactive-labeled antigen can be assessed to determine the amount of antigen in the sample. The analysis is performed by measuring the level of radiation emitted either by the bound complex following removal of the solution containing the free antigen, or by the isolated solution containing the residual-free antigen. The main advantage of the RIA method is the extreme sensitivity of detection for emitted radiation and the corresponding ability to detect trace amounts of antigen. Additionally, large numbers of tests can be performed rapidly.
The enzyme-linked immunosorbent assay (ELISA) techniques are similar to RIA techniques except that nonradioactive labels are employed. This technique is safe, specific and rapid, and is nearly as sensitive as RIA techniques. An enzyme-labeled antigen is used in the immunologic assay; the labeled antigen detects the presence and quantity of unlabeled antigen in the sample. In a representative ELISA test, a plastic plate is coated with antibody (e.g., antibody to B2M). The antibody reacts with antigen (B2M) in the urine and forms an antigen-antibody complex on the plate. A second anti-B2M antibody ( i.e., labeled with an enzyme) is added to the mixture and forms an antibody-antigen-antibody complex. Enzyme activity is measured spectrophotometrically after the addition of a specific chromogenic substrate which is activated by the bound enzyme. The results of a typical test are calculated by comparing the spectrophotometric reading of a serum sample to that of a control or reference serum. In general, these procedures are faster and require less laboratory work than other methods.
In a fluorescent ELISA technique (such as the one employed in the Pharmacia Delphia test for B2M), the labeled enzyme is bound to a strong fluorescent dye. In the Pharmacia Delphia test, an antigen bound to a fluorescent dye competes with unlabeled antigen in the sample for a predetermined amount of specific, immobile antibody. Once equilibrium is reached, the immobile phase is removed from the labeled antigen in the sample solution and washed; an enhancement solution then is added that liberates the fluorescent dye from the bound antigen-antibody complex. The enhancement solution also contains a chelate that complexes with the fluorescent dye in solution; this complex increases the fluorescent properties of the dye so that it is easier to detect.
To determine the quantity of B2M in a sample using the Pharmacia Delphia test, the intensity of the fluorescence of the enhancement solution is measured. This intensity is proportional to the concentration of labeled antigen that bound to the immobile antibody phase during the initial competition with unlabeled antigen from the sample. Consequently, the intensity of the fluorescence is an inverse function of the concentration of antigen (B2M) in the original sample. The relationship between the fluorescence level and the B2M concentration in the sample is determined using a series of graded standards, and extrapolating these standards to find the concentration of the unknown sample.
5.3.3 Methods Developed for B2MU Determinations
B2MU usually is measured by radioimmunoassay (RIA) or enzyme-linked immunosorbent assay (ELISA); however, other methods (including gel electrophoresis, radial immunodiffusion, and nephelometric assays) also have been described (Schardun and van Epps 1987). RIA and ELISA methods are preferred because they are sensitive at concentrations as low as micrograms per liter, require no concentration processes, are highly reliable and use only a small sample volume.
Based on a survey of the literature, the ELISA technique is recommended for monitoring B2MU. While RIAs provide greater sensitivity (typically about 1 µg/l, Evrin et al. 1971), they depend on the use of radioisotopes; use of radioisotopes requires adherence to rules and regulations established by the Atomic Energy Commission, and necessitates an expensive radioactivity counter for testing. Radioisotopes also have a relatively short half-life, which corresponds to a reduced shelf life, thereby increasing the cost and complexity of testing. In contrast, ELISA testing can be performed on routine laboratory spectrophotometers, do not necessitate adherence to additional rules and regulations governing the handling of radioactive substances, and the test kits have long shelf lives. Further, the range of sensitivity commonly achieved by the recommended ELISA test ( i.e., the Pharmacia Delphia test) is approximately 100 µg/l (Pharmacia 1990), which is sufficient for monitoring B2MU levels resulting from cadmium exposure. Based on the studies listed in Table 9 (Section 5.3.7), the average range of B2M concentrations among the general, nonexposed population falls between 60 and 300 µg/g CRTU. The upper 95th percentile of distributions, derived from studies in Table 9 which reported standard deviations, range between 180 and 1,140 µg/g CRTU. Also, the Pharmacia Delphia test currently is the most widely used test for assessing B2MU.
5.3.4 Sample Collection and Handling
As with CDB or CDU, sample collection procedures are addressed primarily to identify ways to minimize the degree of variability introduced by sample collection during medical monitoring. It is unclear the extent to which sample collection contributes to B2MU variability. Sources of variation include time-of-day effects, the interval since consuming liquids and the quantity of liquids consumed, and the introduction of external contamination during the collection process. A special problem unique to B2M sampling is the sensitivity of this protein to degradation under acid conditions commonly found in the bladder. To minimize this problem, strict adherence to a sampling protocol is recommended. The protocol should include provisions for normalizing the conditions under which the urine is collected. Clearly, it is important to minimize the interval urine spends in the bladder. It also is recommended that every effort be made to collect samples during the same time of day.
Collection of urine samples for biological monitoring usually is performed using “spot” ( i.e., single-void) urine. Logistics and sample integrity become problems when efforts are made to collect urine over extended periods (e.g., 24 hrs). Unless single-void urines are used, numerous opportunities exist for measurement error because of poor control over sample collection, storage and environmental contamination.
To minimize the interval that sample urine resides in the bladder, the following adaption to the “spot” collection procedure is recommended: The bladder should be emptied and then a large glass of water should be consumed; the sample then should be collected within an hour after the water is consumed.
5.3.5 Best Achievable Performance
The best achievable performance is assumed to be equivalent to the performance reported by the manufacturers of the Pharmacia Delphia test kits (Pharmacia 1990). According to the insert that comes with these kits, QC results should be within ±2 SDs of the mean for each control sample tested; a CV of less than or equal to 5.2% should be maintained. The total CV reported for test kits is less than or equal to 7.2%.
5.3.6 General Method Performance
Unlike analyses for CDB and CDU, the Pharmacia Delphia test is standardized in a commercial kit that controls for many sources of variation. In the absence of data to the contrary, it is assumed that the achievable performance reported by the manufacturer of this test kit will serve as an achievable performance objective. The CTQ proficiency testing program for B2MU analysis is expected to use the performance parameters defined by the test kit manufacturer as the basis of the B2MU proficiency testing program.
Note that results reported for the test kit are expressed in terms of µg B2M/l of urine, and have not been adjusted for creatinine. The indicated performance, therefore, is a measure of the performance of the B2M portion of the analyses only, and does not include variation that may have been introduced during the analysis of creatinine.
5.3.7 Observed B2MU Concentrations
As indicated in Section 4.3, the concentration of B2MU may serve as an early indicator of the onset of kidney damage associated with cadmium exposure.
5.3.7.1 Range of B2MU concentrations among unexposed samples
Most of the studies listed in Table 9 report B2MU levels for those who were not occupationally exposed to cadmium. Studies noted in the second column of this table (which contain the footnote “d”) reported B2MU concentrations among cadmium-exposed workers who, nonetheless, showed no signs of proteinuria. These latter studies are included in this table because, as indicated in Section 4.3, monitoring B2MU is intended to provide advanced warning of the onset of kidney dysfunction associated with cadmium exposure, rather than to distinguish relative exposure. This table, therefore, indicates the range of B2MU levels observed among those who had no symptoms of renal dysfunction (including cadmium-exposed workers with none of these symptoms).
| Study No. | No. in study | Geometric mean | Geometric standard deviation | Lower 95th percentile of distribution a | Upper 95th percentile of distribution a | Reference |
|---|---|---|---|---|---|---|
| 1 | 133 m b | 115 µg/g c | 4.03 | 12 | 1,140 µg/g c | Ishizaki et al. 1989. |
| 2 | 161 f b | 146 µg/g c | 3.11 | 23 | 940 µg/g c | Ishizaki et al. 1989. |
| 3 | 10 | 84 µg/g | Ellis et al. 1983. | |||
| 4 | 203 | 76 µg/l | Stewart and Hughes 1981. | |||
| 5 | 9 | 103 µg/g | Chia et al. 1989. | |||
| 6 | 47 d | 86 µg/L | 1.9 | 30 µg/1 | 250 µg/L | Kjellstrom et al. 1977. |
| 7 | 1,000 e | 68.1 µg/gr Cr f | 3.1 m & f | <10 µg/gr Cr h | 320 µg/gr Cr h | Kowal 1983. |
| 8 | 87 | 71 µg/g i | 7 h | 200 h | Buchet et al. 1980. | |
| 9 | 10 | 0.073 mg/24h | Evrin et al. 1971. | |||
| 10 | 59 | 156 µg/g | 1.1 j | 130 | 180 | Mason et al. 1988. |
| 11 | 8 | 118 µg/g | Iwao et al. 1980. | |||
| 12 | 34 | 79 µg/g | Wibowo et al. 1982. | |||
| 13 | 41 m | 400 µg/gr Cr k | Falck et al. 1983. | |||
| 14 | 35 n | 67 | Roels et al. 1991. | |||
| 15 | 31 d | 63 | Roels et al. 1991. | |||
| 16 | 36 d | 77 i | Miksche et al. 1981. | |||
| 17 | 18 n | 130 | Kawada et al. 1989. | |||
| 18 | 32 p | 122 | Kawada et al. 1989. | |||
| 19 | 18 d | 295 | 1.4 | 170 | 510 | Thun et al. 1989. |
| a—Based on an assumed lognormal distribution. | ||||||
| b—m = males, f = females. | ||||||
| c—Aged general population from non-polluted area; 47.9% population aged 50-69; 52.1% ≥70 years of age; values reported in study. | ||||||
| d—Exposed workers without proteinuria. | ||||||
| e—492 females, 484 male. | ||||||
| f—Creatinine adjusted; males = 68.1 µg/g Cr, females = 64.3 µg/g Cr. | ||||||
| h—Reported in the study. | ||||||
| i—Arithmetic mean. | ||||||
| j—Geometric standard error. | ||||||
| k—Upper 95% tolerance limits: for Falck this is based on the 24 hour urine sample. | ||||||
| n—Controls. | ||||||
| p—Exposed synthetic resin and pigment workers without proteinuria; Cadmium in urine levels up to 10 µg/g Cr. |
To the extent possible, the studies listed in Table 9 provide geometric means and geometric standard deviations for measurements among the groups defined in each study. For studies reporting a geometric standard deviation along with a mean, the lower and upper 95th percentile for these distributions were derived and reported in the table.
The data provided from 15 of the 19 studies listed in Table 9 indicate that the geometric mean concentration of B2M observed among those who were not occupationally exposed to cadmium is 70-170 µg/g CRTU. Data from the 4 remaining studies indicate that exposed workers who exhibit no signs of proteinuria show mean B2MU levels of 60-300 µg/g CRTU. B2MU values in the study by Thun et al. (1989), however, appear high in comparison to the other 3 studies. If this study is removed, B2MU levels for those who are not occupationally exposed to cadmium are similar to B2MU levels found among cadmium-exposed workers who exhibit no signs of kidney dysfunction. Although the mean is high in the study by Thun et al., the range of measurements reported in this study is within the ranges reported for the other studies.
Determining a reasonable upper limit from the range of B2M concentrations observed among those who do not exhibit signs of proteinuria is problematic. Elevated B2MU levels are among the signs used to define the onset of kidney dysfunction. Without access to the raw data from the studies listed in Table 9, it is necessary to rely on reported standard deviations to estimate an upper limit for normal B2MU concentrations ( i.e., the upper 95th percentile for the distributions measured). For the 8 studies reporting a geometric standard deviation, the upper 95th percentiles for the distributions are 180-1140 µg/g CRTU. These values are in general agreement with the upper 95th percentile for the distribution ( i.e., 631 µg/g CRTU) reported by Buchet et al. (1980). These upper limits also appear to be in general agreement with B2MU values ( i.e., 100-690 µg/g CRTU) reported as the normal upper limit by Iwao et al. (1980), Kawada et al. (1989), Wibowo et al. (1982), and Schardun and van Epps (1987). These values must be compared to levels reported among those exhibiting kidney dysfunction to define a threshold level for kidney dysfunction related to cadmium exposure.
5.3.7.2 Range of B2MU concentrations among exposed workers
| Study No. | N | Concentration of B-2-Microglobulin in urine | Reference | |||
|---|---|---|---|---|---|---|
| Geometric mean (µg/g) a | Geom std dev | L 95% of range b | U 95% of range b | |||
| 1 | 1,42 4 | 160 | 6.19 | 8.1 | 3,300 | Ishizaki et al., 1989. |
| 2 | 1,75 4 | 260 | 6.50 | 12 | 5,600 | Ishizaki et al., 1989. |
| 3 | 33 | 210 | Ellis et al., 1983. | |||
| 4 | 65 | 210 | Chia et al., 1989. | |||
| 5 | c 44 | 5,700 | 6.49 | d 300 | d 98,000 | Kjellstrom et al., 1977. |
| 6 | 148 | e 180 | f 110 | f 280 | Buchet et al., 1980. | |
| 7 | 37 | 160 | 3.90 | 17 | 1,500 | Kenzaburo et al., 1979. |
| 8 | c 45 | 3,300 | 8.7 | d 310 | d 89,000 | Mason et al., 1988. |
| 9 | c 10 | 6,100 | 5.99 | f 650 | f 57,000 | Falck et al., 1983. |
| 10 | c 11 | 3,900 | 2.96 | d 710 | d 15,000 | Elinder et al., 1985. |
| 11 | c 12 | 300 | Roels et al., 1991. | |||
| 12 | g 8 | 7,400 | Roels et al., 1991. | |||
| 13 | c 23 | h 1,800 | Roels et al., 1989. | |||
| 14 | 10 | 690 | Iwao et al., 1980. | |||
| 15 | 34 | 71 | Wibowo et al., 1982. | |||
| 16 | c 15 | 4,700 | 6.49 | d 590 | d 93,000 | Thun et al., 1989. |
| a Unless otherwise stated. | ||||||
| b Based on an assumed lognormal distribution. | ||||||
| c Among workers diagnosed as having renal dysfunction; for Elinder this means β 2 levels greater than 300 micrograms per gram creatinine (µg/gr Cr); for Roels, 1991, range = 31 − 35, 170 µgβ 2 /gr Cr and geometric mean = 63 among healthy workers; for Mason β 2 >300 µg/gr Cr. | ||||||
| d Based on a detailed review of the data by OSHA. | ||||||
| e Arthmetic mean. | ||||||
| f Reported in the study. | ||||||
| g Retired workers. | ||||||
| h 1,800 µgβ 2 /gr Cr for first survey; second survey = 1,600; third survey = 2,600; fourth survey = 2,600; fifth survey = 2,600. |
The data provided in Table 10 indicate that the mean B2MU concentration observed among workers experiencing occupational exposure to cadmium (but with undefined levels of proteinuria) is 160-7400 µg/g CRTU. One of these studies reports geometric means lower than this range ( i.e., as low as 71 µg/g CRTU); an explanation for this wide spread in average concentrations is not available.
Seven of the studies listed in Table 10 report a range of B2MU levels among those diagnosed as having renal dysfunction. As indicated in this table, renal dysfunction (proteinuria) is defined in several of these studies by B2MU levels in excess of 300 µg/g CRTU (see footnote “c” of Table 10); therefore, the range of B2MU levels observed in these studies is a function of the operational definition used to identify those with renal dysfunction. Nevertheless, a B2MU level of 300 µg/g CRTU appears to be a meaningful threshold for identifying those having early signs of kidney damage. While levels much higher than 300 µg/g CRTU have been observed among those with renal dysfunction, the vast majority of those not occupationally exposed to cadmium exhibit much lower B2MU concentrations (see Table 9). Similarly, the vast majority of workers not exhibiting renal dysfunction are found to have levels below 300 µg/g CRTU (Table 9).
The 300 µg/g CRTU level for B2MU proposed in the above paragraph has support among researchers as the threshold level that distinguishes between cadmium-exposed workers with and without kidney dysfunction. For example, in the guide for physicians who must evaluate cadmium-exposed workers written for the Cadmium Council by Dr. Lauwerys, levels of B2M greater than 200-300 µg/g CRTU are considered to require additional medical evaluation for kidney dysfunction (exhibit 8-447, OSHA docket H057A). The most widely used test for measuring B2M ( i.e., the Pharmacia Delphia test) defines B2MU levels above 300 µg/l as abnormal (exhibit L-140-1, OSHA docket H057A).
Dr. Elinder, chairman of the Department of Nephrology at the Karolinska Institute, testified at the hearings on the proposed cadmium rule. According to Dr. Elinder (exhibit L-140-45, OSHA docket H057A), the normal concentration of B2MU has been well documented (Evrin and Wibell 1972; Kjellstrom et al. 1977a; Elinder et al. 1978, 1983; Buchet et al. 1980; Jawaid et al. 1983; Kowal and Zirkes, 1983). Elinder stated that the upper 95 or 97.5 percentiles for B2MU among those without tubular dysfunction is below 300 µg/g CRTU (Kjellstrom et al. 1977a; Buchet et al. 1980; Kowal and Zirkes, 1983). Elinder defined levels of B2M above 300 µg/g CRTU as “slight” proteinuria.
5.3.8 Conclusions and Recommendations for B2MU
Based on the above evaluation, the following recommendations are made for a B2MU proficiency testing program. Note that the following discussion addresses only sampling and analysis for B2MU determinations ( i.e., to be reported as an unadjusted µg B2M/l urine). Normalizing this result to creatinine requires a second analysis for CRTU (see Section 5.4) so that the ratio of the 2 measurements can be obtained.
5.3.8.1 Recommended method
The Pharmacia Delphia method (Pharmacia 1990) should be adopted as the standard method for B2MU determinations. Laboratories may adopt alternate methods, but it is the responsibility of the laboratory to demonstrate that alternate methods provide results of comparable quality to the Pharmacia Delphia method.
5.3.8.2 Data quality objectives
The following data quality objectives should facilitate interpretation of analytical results, and should be achievable based on the above evaluation.
Limit of Detection. A limit of 100 µg/l urine should be achievable, although the insert to the test kit (Pharmacia 1990) cites a detection limit of 150 µg/l; private conversations with representatives of Pharmacia, however, indicate that the lower limit of 100 µg/l should be achievable provided an additional standard of 100 µg/l B2M is run with the other standards to derive the calibration curve (Section 3.3.1.1). The lower detection limit is desirable due to the proximity of this detection limit to B2MU values defined for the cadmium medical monitoring program.
Accuracy. Because results from an interlaboratory proficiency testing program are not available currently, it is difficult to define an achievable level of accuracy. Given the general performance parameters defined by the insert to the test kits, however, an accuracy of ±15% of the target value appears achievable.
Due to the low levels of B2MU to be measured generally, it is anticipated that the analysis of creatinine will contribute relatively little to the overall variability observed among creatinine-normalized B2MU levels (see Section 5.4). The initial level of accuracy for reporting B2MU levels under this program should be set at ±15%.
Precision. Based on precision data reported by Pharmacia (1990), a precision value ( i.e., CV) of 5% should be achievable over the defined range of the analyte. For internal QC samples ( i.e., recommended as part of an internal QA/QC program, Section 3.3.1), laboratories should attain precision near 5% over the range of concentrations measured.
5.3.8.3 Quality assurance/quality control
Commercial laboratories providing measurement of B2MU should adopt an internal QA/QC program that incorporates the following components: Strict adherence to the Pharmacia Delphia method, including calibration requirements; regular use of QC samples during routine runs; a protocol for corrective actions, and documentation of these actions; and, participation in an interlaboratory proficiency program. Procedures that may be used to address internal QC requirements are presented in Attachment 1. Due to differences between analyses for B2MU and CDB/CDU, specific values presented in Attachment 1 may have to be modified. Other components of the program (including characterization runs), however, can be adapted to a program for B2MU.
5.4 Monitoring Creatinine in Urine (CRTU)
Because CDU and B2MU should be reported relative to concentrations of CRTU, these concentrations should be determined in addition CDU and B2MU determinations.
5.4.1 Units of CRTU Measurement
CDU should be reported as µg Cd/g CRTU, while B2MU should be reported as µg B2M/g CRTU. To derive the ratio of cadmium or B2M to creatinine, CRTU should be reported in units of g crtn/l of urine. Depending on the analytical method, it may be necessary to convert results of creatinine determinations accordingly.
5.4.2 Analytical Techniques Used To Monitor CRTU
Of the techniques available for CRTU determinations, an absorbance spectrophotometric technique and a high-performance liquid chromatography (HPLC) technique are identified as acceptable in this protocol.
5.4.3 Methods Developed for CRTU Determinations
CRTU analysise performed in support of either CDU or B2MU determinations should be performed using either of the following 2 methods:
1. The Du Pont method ( i.e., Jaffe method), in which creatinine in a sample reacts with picrate under alkaline conditions, and the resulting red chromophore is monitored (at 510 nm) for a fixed interval to determine the rate of the reaction; this reaction rate is proportional to the concentration of creatinine present in the sample (a copy of this method is provided in Attachment 2 of this protocol); or,
2. The OSHA SLC Technical Center (OSLTC) method, in which creatinine in an aliquot of sample is separated using an HPLC column equipped with a UV detector; the resulting peak is quantified using an electrical integrator (a copy of this method is provided in Attachment 3 of this protocol).
5.4.4 Sample Collection and Handling
CRTU samples should be segregated from samples collected for CDU or B2MU analysis. Sample-collection techniques have been described under Section 5.2.4. Samples should be preserved either to stabilize CDU (with HNO 3 ) or B2MU (with NaOH). Neither of these procedures should adversely affect CRTU analysis (see Attachment 3).
5.4.5 General Method Performance
Data from the OSLTC indicate that a CV of 5% should be achievable using the OSLTC method (Septon, L private communication). The achievable accuracy of this method has not been determined.
Results reported in surveys conducted by the CAP (CAP 1991a, 1991b and 1992) indicate that a CV of 5% is achievable. The accuracy achievable for CRTU determinations has not been reported.
Laboratories performing creatinine analysis under this protocol should be CAP accredited and should be active participants in the CAP surveys.
5.4.6 Observed CRTU Concentrations
Published data suggest the range of CRTU concentrations is 1.0-1.6 g in 24-hour urine samples (Harrison 1987). These values are equivalent to about 1 g/l urine.
5.4.7 Conclusions and Recommendations for CRTU
5.4.7.1 Recommended method
Use either the Jaffe method (Attachment 2) or the OSLTC method (Attachment 3). Alternate methods may be acceptable provided adequate performance is demonstrated in the CAP program.
5.4.7.2 Data quality objectives
Limit of Detection. This value has not been formally defined; however, a value of 0.1 g/l urine should be readily achievable.
Accuracy. This value has not been defined formally; accuracy should be sufficient to retain accreditation from the CAP.
Precision. A CV of 5% should be achievable using the recommended methods.
6.0 References
Adamsson E, Piscator M, and Nogawa K. (1979). Pulmonary and gastrointestinal exposure to cadmium oxide dust in a battery factory. Environmental Health Perspectives, 28, 219-222.
American Conference of Governmental Industrial Hygienists (ACGIH). (1986). Documentation of the Threshold Limit Values and Biological Exposure Indices. 5th edition. p. BEI-55.
Bernard A, Buchet J, Roels H, Masson P, and Lauwerys R. (1979). Renal excretion of proteins and enzymes in workers exposed to cadmium. European Journal of Clinical Investigation, 9, 11-22.
Bernard A and Lauwerys R. (1990). Early markers of cadmium nephrotoxicity: Biological significance and predictive value. Toxocological and Environmental Chemistry, 27, 65-72.
Braunwald E, Isselbacher K, Petersdorf R, Wilson J, Martin J, and Fauci A (Eds.). (1987). Harrison's Principles of Internal Medicine. New York: McGraw-Hill Book Company.
Buchet J, Roels H, Bernard I, and Lauwerys R. (1980). Assessment of renal funcion of workers exposed to inorganic lead, cadmium, or mercury vapor. Journal of Occupational Medicine, 22, 741-750.
CAP. (1991). Urine Chemistry, Series 1: Survey (Set U-B).
College of American Pathologists.
CAP. (1991). Urine Chemistry, Series 1: Survey (Set U-C). College of American
Pathologists.
CAP. (1992). Urine Chemistry, Series 1: Survey (Set U-A). College of American Pathologists.
CDC. (1986). Centers for Disease Control, Division of Environmental Health Laboratory Sciences, Center for Environmental Health, Atlanta, Georgia. Docket No. 106A. Lake Couer d'Alene, Idaho cadmium and lead study: 86-0030, Specimen collection and shipping protocol.
CDC. (1990). Centers for Disease Control, Nutritional Biochemistry Branch. 4/27/90 Draft SOP for Method 0360A “Determination of cadmium in urine by graphite furnace atomic absorption spectrometry with Zeeman background correction.
Centre de Toxicologie du Quebec. (1991). Interlaboratory comparison program report for run #2. Shipping date 3/11/91. Addition BLR 9/19.
Chia K, Ong C, Ong H, and Endo G. (1989). Renal tubular function of workers exposed to low levels of cadmium. British Journal of Industrial Medicine, 46, 165-170.
Claeys-Thoreau F. (1982). Determination of low levels of cadmium and lead in biological fluids with simple dilution by atomic absorption spectrophotometry using Zeeman effect background absorption and the L'Vov platform. Atomic Spectroscopy, 3, 188-191.
DeBenzo Z, Fraile R, and Carrion N. (1990). Electrothermal atomization atomic absorption spectrometry with stabilized aqueous standards for the determination of cadmium in whole blood. Analytica Chimica Acta, 231, 283-288.
Elinder C, Edling C, Lindberg E, Kagedal B, and Vesterberg O. (1985). Assessment of renal function in workers previously exposed to cadmium. British Journal of Internal Medicine, 42, 754.
Ellis K, Cohn S, and Smith T. (1985). Cadmium inhalation exposure estimates: Their significance with respect to kidney and liver cadmium burden. Journal of Toxicology and Environmental Health, 15, 173-187.
Ellis K, Yasumura S, Vartsky D, and Cohn S. (1983). Evaluation of biological indicators of body burden of cadmium in humans. Fundamentals and Applied Toxicology, 3, 169-174.
Ellis K, Yeun K, Yasumura S, and Cohn S. (1984). Dose-response analysis of cadmium in man: Body burden vs kidney function. Environmental Research, 33, 216-226.
Evrin P, Peterson A, Wide I, and Berggard I. (1971). Radioimmunoassay of B-2-microglobulin in human biological fluids. Scandanavian Journal of Clinical Laboratory Investigation, 28, 439-443.
Falck F, Fine L, Smith R, Garvey J, Schork A, England B, McClatchey K, and Linton J. (1983). Metallothionein and occupational exposure to cadmium. British Journal of Industrial Medicine, 40, 305-313.
Federal Register. (1990). Occupational exposure to cadmium: Proposed rule. 55/22/4052-4147, February 6.
Friberg, Exhibit 29, (1990). Exhibit No. 29 of the OSHA Federal Docket H057A. Washington, DC.
Friberg L. (1988). Quality assurance. In T. Clarkson (Ed.), Biological Monitoring of Toxic Metals (pp. 103-105). New York: Plenum Press.
Friberg L, and Elinder C. (1988). Cadmium toxicity in humans. In Essential and Trace Elements in Human Health and Disease (pp. 559-587). Docket Number 8-660.
Friberg L, Elinder F, et al. (1986). Cadmium and Health: A Toxicological and Epidemiological Appraisal. Volume II, Effects and Response. Boca Raton, FL: CRC Press.
Friberg L, Piscator M, Nordberg G, and Kjellstrom T. (1974). Cadmium in the Environment (2nd ed.). Cleveland:CRC.
Friberg L and Vahter M. (1983). Assessment of exposure to lead and cadmium through biological monitoring: Results of a UNEP/WHO global study. Environmental Research, 30, 95-128.
Gunter E, and Miller D. (1986). Laboratory procedures used by the division of environmental health laboratory sciences center for environmental health, Centers for Disease Control for the hispanic health and nutrition examination survey (HHANES). Atlanta, GA: Centers for Disease Control.
Harrison. (1987). Harrison's Principles of Internal Medicine. Braunwald, E; Isselbacher, KJ; Petersdorf, RG; Wilson, JD; Martin, JB; and Fauci, AS Eds. Eleventh Ed. McGraw Hill Book Company. San Francisco.
Henry J. (1991). Clinical Diagnosis and Management by Laboratory Methods (18th edition). Philadelphia: WB Saunders Company.
IARC (1987). IRAC Monographs on the Evaluation of Carcinogenic Risks to Humans. Overall Evaluation of Carcinogenicity: Update of Volume 1-42. Supplemental 7, 1987.
Ishizaki M, Kido T, Honda R, Tsuritani I, Yamada Y, Nakagawa H, and Nogawa K. (1989). Dose-response relationship between urinary cadmium and B-2-microglobulin in a Japanese environmentally cadmium exposed population. Toxicology, 58, 121-131.
Iwao S, Tsuchiya K, and Sakurai H. (1980). Serum and urinary B-2-microglobulin among cadmium-exposed workers. Journal of Occupational Medicine, 22, 399-402.
Iwata K, Katoh T, Morikawa Y, Aoshima K, Nishijo M, Teranishi H, and Kasuya M. (1988). Urinary trehalase activity as an indicator of kidney injury due to environmental cadmium exposure. Archives of Toxicology, 62, 435-439.
Kawada T, Koyama H, and Suzuki S. (1989). Cadmium, NAG activity, and B-2-microglobulin in the urine of cadmium pigment workers. British Journal of Industrial Medicine, 46, 52-55.
Kawada T, Tohyama C, and Suzuki S. (1990). Significance of the excretion of urinary indicator proteins for a low level of occupational exposure to cadmium. International Archives of Occupational Environmental Health, 62, 95-100.
Kjellstrom T. (1979). Exposure and accumulation of cadmium in populations from Japan, the United States, and Sweden. Environmental Health Perspectives, 28, 169-197.
Kjellstrom T, Evrin P, and Rahnster B. (1977). Dose-response analysis of cadmium-induced tubular proteinuria. Environmental Research, 13, 303-317.
Kjellstrom T, Shiroishi K, and Evrin P. (1977). Urinary B-2-microglobulin excretion among people exposed to cadmium in the general environment. Environmental Research, 13, 318-344.
Kneip T, & Crable J (Eds.). (1988). Method 107. Cadmium in blood. Methods for biological monitoring (pp.161-164). Washington, DC: American Public Health Association.
Kowal N. (1988). Urinary cadmium and B-2-microglobulin: Correlation with nutrition and smoking history. Journal of Toxicology and Environmental Health, 25, 179-183.
Kowal N, Johnson D, Kraemer D, and Pahren H. (1979). Normal levels of cadmium in diet, urine, blood, and tissues of inhabitants of the United States. Journal of Toxicology and Environmental Health, 5, 995-1014.
Kowal N and Zirkes M. (1983). Urinary cadmium and B-2-microglobulin: Normal values and concentration adjustment. Journal of Toxicology and Environmental Health, 11, 607-624.
Lauwerys R, Buchet J, and Roels H. (1976). The relationship between cadmium exposure or body burden and the concentration of cadmium in blood and urine in man. International Archives of Occupational and Environmental Health, 36, 275-285
Lauwerys R, Roels H, Regniers, Buchet J, and Bernard A. (1979). Significance of cadmium concentration in blood and in urine in workers exposed to cadmium. Environmental Research, 20, 375-391.
Lind B, Elinder C, Friberg L, Nilsson B, Svartengren M, and Vahter M. (1987). Quality control in the analysis of lead and cadmium in blood. Fresenius' Zeitschrift fur Analytical Chemistry, 326, 647-655.
Mason H, Davison A, Wright A, Guthrie C, Fayers P, Venables K, Smith N, Chettle D, Franklin D, Scott M, Holden H, Gompertz D, and Newman-Taylor A. (1988). Relations between liver cadmium, cumulative exposure, and renal function in cadmium alloy workers. British Journal of Industrial Medicine, 45, 793-802.
Meridian Research, Inc. (1989). Quantitative Assessment of Cancer Risks Associated with Occupational Exposure to Cd. Prepared by Meridian Research, Inc. and Roth Associates, Inc. for the Occupational Safety & Health Administration. June 12, 1989.
Meridian Research, Inc and Roth Associates, Inc. (1989). Quantitative Assessment of the Risk of Kidney Dysfunction Associated with Occupational Exposure to Cd. Prepared by Meridian Research, Inc. and Roth Associates, Inc. for the Occupational Safety & Health Administration. July 31 1989.
Micheils E and DeBievre P. (1986). Method 25-Determination of cadmium in whole blood by isotope dilution mass spectrometry. O'Neill I, Schuller P, and Fishbein L (Eds.), Environmental Carcinogens Selected Methods of Analysis (Vol. 8). Lyon, France: International Agency for Research on Cancer.
Mueller P, Smith S, Steinberg K, and Thun M. (1989). Chronic renal tubular effects in relation to urine cadmium levels. Nephron, 52, 45-54.
NIOSH. (1984a). Elements in blood or tissues. Method 8005 issued 5/15/85 and Metals in urine. Method 8310 issued 2/15/84 In P. Eller (Ed.), NIOSH Manual of Analytical Methods (Vol. 1, Ed. 3). Cincinnati, Ohio: US-DHHS.
NIOSH. (1984b). Lowry L. Section F: Special considerations for biological samples in NIOSH Manual of Analytical Methods (Vol. 1, 3rd ed). P. Eller (Ed.). Cincinnati, Ohio: US-DHHS.
Nordberg G and Nordberg M. (1988). Biological monitoring of cadmium. In T. Clarkson, L. Friberg, G. Nordberg, and P. Sager (Eds.), Biological Monitoring of Toxic Metals, New York: Plenum Press.
Nogawa K. (1984). Biologic indicators of cadmium nephrotoxicity in persons with low-level cadmium exposure. Environmental Health Perspectives, 54, 163-169.
OSLTC (no date). Analysis of Creatinine for the Normalization of Cadmium and Beta-2-Microglobulin Concentrations in Urine. OSHA Salt Lake Technical Center. Salt Lake City, UT. Paschal. (1990). Attachment 8 of exhibit 106 of the OSHA docket H057A.
Perkin-Elmer Corporation. (1982). Analytical Methods for Atomic Absorption Spectroscopy.
Perkin-Elmer Corporation. (1977). Analytical Methods Using the HGA Graphite Furnace.
Pharmacia Diagnostics. (1990). Pharmacia DELFIA system B-2-microglobulin kit insert. Uppsala, Sweden: Pharmacia Diagnostics.
Piscator M. (1962). Proteinuria in chronic cadmium poisoning. Archives of Environmental Health,5, 55-62.
Potts, C.L. (1965). Cadmium Proteinuria—The Health Battery Workers Exposed to Cadmium Oxide dust. Ann Occup Hyg, 3:55-61, 1965.
Princi F. (1947). A study of industrial exposures to cadmium. Journal of Industrial Hygiene and Toxicology, 29, 315-320.
Pruszkowska E, Carnick G, and Slavin W. (1983). Direct determination of cadmium in urine with use of a stabilized temperature platform furnace and Zeeman background correction. Clinical Chemistry, 29, 477-480.
Roberts C and Clark J. (1986). Improved determination of cadmium in blood and plasma by flameless atomic absorption spectroscopy. Bulletin of Environmental Contamination and Toxicology, 36, 496-499.
Roelandts I. (1989). Biological reference materials. Soectrochimica Acta, 44B, 281-290.
Roels H, Buchet R, Lauwerys R, Bruaux P, Clays-Thoreau F, Laafontaine A, Overschelde J, and Verduyn J. (1978). Lead and cadmium absorption among children near a nonferrous metal plant. Environmental Research, 15, 290-308.
Roels H, Djubgang J, Buchet J, Bernard A, and Lauwerys R. (1982). Evolution of cadmium-induced renal dysfunction in workers removed from exposure. Scandanavian Journal of Work and Environmental Health, 8, 191-200.
Roels H, Lauwerys R, and Buchet J. (1989). Health significance of cadmium induced renal dysfunction: A five year follow-up. British Journal of Industrial Medicine, 46, 755-764.
Roels J, Lauwerys R, Buchet J, Bernard A, Chettle D, Harvey T, and Al-Haddad I. (1981). In vivo measurements of liver and kidney cadmium in workers exposed to this metal: Its significance with respect to cadmium in blood and urine. Environmental Research, 26, 217-240.
Roels H, Lauwerys R, Buchet J, Bernard A, Lijnen P, and Houte G. (1990). Urinary kallikrein activity in workers exposed to cadmium, lead, or mercury vapor. British Journal of Industrial Medicine, 47, 331-337.
Sakurai H, Omae K, Toyama T, Higashi T, and Nakadate T. (1982). Cross-sectional study of pulmonary function in cadmium alloy workers. Scandanavian Journal of Work and Environmental Health, 8, 122-130.
Schardun G and van Epps L. (1987). B-2-microglobulin: Its significance in the evaluation of renal function. Kidney International, 32, 635-641.
Shaikh Z, and Smith L. (1984). Biological indicators of cadmium exposure and toxicity. Experentia, 40, 36-43.
Smith J and Kench J. (1957). Observations on urinary cadmium and protein excretion in men exposed to cadmium oxide dust and fume. British Journal of Industrial Medicine, 14, 240-245.
Smith J, Kench J, and Lane R. (1955). Determination of Cadmium in urine and observations on urinary cadmium and protein excretion in men exposed to cadmium oxide dust. British Journal of Industrial Medicine, 12, 698-701.
SWRI (Southwest Research Institute). (1978). The distribution of cadmium and other metals in human tissues. Health Effects Research Lab, Research Triangle Park, NC, Population Studies Division. NTIS No. PB-285-200.
Stewart M and Hughes E. (1981). Urinary B-2-microglobulin in the biological monitoring of cadmium workers. British Journal of Industrial Medicine, 38, 170-174.
Stoeppler K and Brandt M. (1980). Contributions to automated trace analysis. part V. Determination of cadmium in whole blood and urine by electrothermal atomic absorption spectrophotometry. Fresenius' Zeitschrift fur Analytical Chemistry, 300, 372-380.
Takenaka et al. (1983). Carcinogencity of Cd Chloride Aerosols in White Rates. INCI 70: 367-373, 1983.
Thun M, Osorio A, Schober S, Hannon W, Lewis B, and Halperin W. (1989). Nephropathy in cadmium workers: Assessment of risk from airborne occupational exposure to cadmium. British Journal of Industrial Medicine, 46, 689-697.
Thun M, Schnorr T, Smith A, Halperin W, and Lemen R. (1985). Mortality among a cohort of US cadmium production workers—an update. Journal of the National Cancer Institute, 74, 325-333.
Travis D and Haddock A. (1980). Interpretation of the observed age-dependency of cadmium body burdens in man. Environmental Research, 22, 46-60.
Tsuchiya K. (1967). Proteinuria of workers exposed to cadmium fume. Archives of Environmental Health, 14, 875-880.
Tsuchiya K. (1976). Proteinuria of cadmium workers. Journal of Occupational Medicine, 18, 463-470.
Tsuchiya K, Iwao S, Sugita M, Sakurai H. (1979). Increased urinary B-2-microglobulin in cadmium exposure: Dose-effect relationship and biological significance of B-2-microglobulin. Environmental Health Perspectives, 28, 147-153.
USEPA. (1985). Updated Mutagenicity and Carcinogenicity Assessments of Cd: Addendum to the Health Assessment Document for Cd (May 1981). Final Report. June 1985.
Vahter M and Friberg L. (1988). Quality control in integrated human exposure monitoring of lead and cadmium. Fresenius' Zeitschrift fur Analytical Chemistry, 332, 726-731.
Weber J. (1988). An interlaboratory comparison programme for several toxic substances in blood and urine. The Science of the Total Environment, 71, 111-123.
Weber J. (1991a). Accuracy and precision of trace metal determinations in biological fluids. In K. Subramanian, G. Iyengar, and K. Okamot (Eds.), Biological Trace Element Research -Multidisciplinary Perspectives, ACS Symposium Series 445. Washington, DC: American Chemical Society.
Weber J. (1991b). Personal communication about interlaboratory program and shipping biological media samples for cadmium analyses.
Wibowo A, Herber R, van Deyck W, and Zielhuis R. (1982). Biological assessment of exposure in factories with second degree usage of cadmium compounds. International Archives of Occupational Environmental Health, 49, 265-273.
Attachment 1—Nonmandatory Protocol for an Internal Quality Assurance/Quality Control Program
The following is an example of the type of internal quality assurance/quality control program that assures adequate control to satisfy OSHA requirements under this protocol. However, other approaches may also be acceptable.
As indicated in Section 3.3.1 of the protocol, the QA/QC program for CDB and CDU should address, at a minimum, the following:
• calibration;
• establishment of control limits;
• internal QC analyses and maintaining control; and
• corrective action protocols.
This illustrative program includes both initial characterization runs to establish the performance of the method and ongoing analysis of quality control samples intermixed with compliance samples to maintain control.
Calibration
Before any analytical runs are conducted, the analytic instrument must be calibrated. This is to be done at the beginning of each day on which quality control samples and/or compliance samples are run. Once calibration is established, quality control samples or compliance samples may be run. Regardless of the type of samples run, every fifth sample must be a standard to assure that the calibration is holding.
Calibration is defined as holding if every standard is within plus or minus (±) 15% of its theoretical value. If a standard is more than plus or minus 15% of its theoretical value, then the run is out of control due to calibration error and the entire set of samples must either be reanalyzed after recalibrating or results should be recalculated based on a statistical curve derived from the measurement of all standards.
It is essential that the highest standard run is higher than the highest sample run. To assure that this is the case, it may be necessary to run a high standard at the end of the run, which is selected based on the results obtained over the course of the run.
All standards should be kept fresh, and as they get old, they should be compared with new standards and replaced if they exceed the new standards by ±15%.
Initial Characterization Runs and Establishing Control
A participating laboratory should establish four pools of quality control samples for each of the analytes for which determinations will be made. The concentrations of quality control samples within each pool are to be centered around each of the four target levels for the particular analyte identified in Section 4.4 of the protocol.
Within each pool, at least 4 quality control samples need to be established with varying concentrations ranging between plus or minus 50% of the target value of that pool. Thus for the medium-high cadmium in blood pool, the theoretical values of the quality control samples may range from 5 to 15 µg/l, (the target value is 10 µg/l). At least 4 unique theoretical values must be represented in this pool.
The range of theoretical values of plus or minus 50% of the target value of a pool means that there will be overlap of the pools. For example, the range of values for the medium-low pool for cadmium in blood is 3.5 to 10.5 µg/l while the range of values for the medium-high pool is 5 to 15 µg/l. Therefore, it is possible for a quality control sample from the medium-low pool to have a higher concentration of cadmium than a quality control sample from the medium-high pool.
Quality control samples may be obtained as commercially available reference materials, internally prepared, or both. Internally prepared samples should be well characterized and traced or compared to a reference material for which a consensus value for concentration is available. Levels of analyte in the quality control samples must be concealed from the analyst prior to the reporting of analytical results. Potential sources of materials that may be used to construct quality control samples are listed in Section 3.3.1 of the protocol.
Before any compliance samples are analyzed, control limits must be established. Control limits should be calculated for every pool of each analyte for which determinations will be made and control charts should be kept for each pool of each analyte. A separate set of control charts and control limits should be established for each analytical instrument in a laboratory that will be used for analysis of compliance samples.
At the beginning of this QA/QC program, control limits should be based on the results of the analysis of 20 quality control samples from each pool of each analyte. For any given pool, the 20 quality control samples should be run on 20 different days. Although no more than one sample should be run from any single pool on a particular day, a laboratory may run quality control samples from different pools on the same day. This constitutes a set of initial characterization runs.
For each quality control sample analyzed, the value F/T (defined in the glossary) should be calculated. To calculate the control limits for a pool of an analyte, it is first necessary to calculate the mean, X, of the F/T values for each quality control sample in a pool and then to calculate its standard deviation σ. Thus, for the control limit for a pool, X is calculated as:
and σ is calculated as
Where N is the number of quality control samples run for a pool.
The control limit for a particular pool is then given by the mean plus or minus 2 standard deviations (X ±3σ).
The control limits may be no greater than 40% of the mean F/T value. If three standard deviations are greater than 40% of the mean F/T value, then analysis of compliance samples may not begin. 1 Instead, an investigation into the causes of the large standard deviation should begin, and the inadequacies must be remedied. Then, control limits must be reestablished which will mean repeating the running 20 quality control samples from each pool over 20 days.
1 Note that the value,“40%” may change over time as experience is gained with the program.
Internal Quality Control Analyses and Maintaining Control
Once control limits have been established for each pool of an analyte, analysis of compliance samples may begin. During any run of compliance samples, quality control samples are to be interspersed at a rate of no less than 5% of the compliance sample workload. When quality control samples are run, however, they should be run in sets consisting of one quality control sample from each pool. Therefore, it may be necessary, at times, to intersperse quality control samples at a rate greater than 5%.
There should be at least one set of quality control samples run with any analysis of compliance samples. At a minimum, for example, 4 quality control samples should be run even if only 1 compliance sample is run. Generally, the number of quality control samples that should be run are a multiple of four with the minimum equal to the smallest multiple of four that is greater than 5% of the total number of samples to be run. For example, if 300 compliance samples of an analyte are run, then at least 16 quality control samples should be run (16 is the smallest multiple of four that is greater than 15, which is 5% of 300).
Control charts for each pool of an analyte (and for each instrument in the laboratory to be used for analysis of compliance samples) should be established by plotting F/T versus date as the quality control sample results are reported. On the graph there should be lines representing the control limits for the pool, the mean F/T limits for the pool, and the theoretical F/T of 1.000. Lines representing plus or minus (±) σ should also be represented on the charts. A theoretical example of a control chart is presented in Figure 1.
| 1.162 (Upper Control Limit) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| X | ||||||||||
| 1.096 (Upper 2σ Line) | ||||||||||
| X | ||||||||||
| X | 1.000 (Theoretical Mean) | |||||||||
| X | X | 0.964 (Mean) | ||||||||
| X | X | |||||||||
| X | ||||||||||
| X | 0.832 (Lower 2σ Line) | |||||||||
| X | ||||||||||
| 0.766 (Lower Control Limit) | ||||||||||
| March | 2 | 2 | 3 | 5 | 6 | 9 | 10 | 13 | 16 | 17 |
All quality control samples should be plotted on the chart, and the charts should be checked for visual trends. If a quality control sample falls above or below the control limits for its pool, then corrective steps must be taken (see the section on corrective actions below). Once a laboratory's program has been established, control limits should be updated every 2 months.
The updated control limits should be calculated from the results of the last 100 quality control samples run for each pool. If 100 quality control samples from a pool have not been run at the time of the update, then the limits should be based on as many as have been run provided at least 20 quality control samples from each pool have been run over 20 different days.
The trends that should be looked for on the control charts are:
1. 10 consecutive quality control samples falling above or below the mean;
2. 3 consecutive quality control samples falling more than 2σ from the mean (above or below the 2σ lines of the chart); or
3. the mean calculated to update the control limits falls more than 10% above or below the theoretical mean of 1.000.
If any of these trends is observed, then all analysis must be stopped, and an investigation into the causes of the errors must begin. Before the analysis of compliance samples may resume, the inadequacies must be remedied and the control limits must be reestablished for that pool of an analyte. Reestablishment of control limits will entail running 20 sets of quality control samples over 20 days.
Note that alternative procedures for defining internal quality control limits may also be acceptable. Limits may be based, for example, on proficiency testing, such as ±1 µg or 15% of the mean (whichever is greater). These should be clearly defined.
Corrective actions
Corrective action is the term used to describe the identification and remediation of errors occurring within an analysis. Corrective action is necessary whenever the result of the analysis of any quality control sample falls outside of the established control limits. The steps involved may include simple things like checking calculations of basic instrument maintenance, or it may involve more complicated actions like major instrument repair. Whatever the source of error, it must be identified and corrected (and a Corrective Action Report (CAR) must be completed. CARs should be kept on file by the laboratory.
Attachment 2—Creatinine in Urine (Jaffe Procedure)
Intended use: The CREA pack is used in the Du Pont ACA ® discrete clinical analyzer to quantitatively measure creatinine in serum and urine.
Summary: The CREA method employs a modification of the kinetic Jaffe reaction reported by Larsen. This method has been reported to be less susceptible than conventional methods to interference from non-creatinine, Jaffe-positive compounds. 1
A split sample comparison between the CREA method and a conventional Jaffe procedure on Autoanalyzer ® showed a good correlation. (See Specific Performance Characteristics).
*Note: Numbered subscripts refer to the bibliography and lettered subscripts refer to footnotes.
Autoanalyzer ®, is a registered trademark of Technicon Corp., Tarrytown, NY.
Principles of Procedure: In the presence of a strong base such as NaOH, picrate reacts with creatinine to form a red chromophore. The rate of increasing absorbance at 510 nm due to the formation of this chromophore during a 17.07-second measurement period is directly proportional to the creatinine concentration in the sample.
Reagents:
| Compartment a | Form | Ingredient | Quantity b |
|---|---|---|---|
| No. 2, 3, & 4 | Liquid | Picrate | 0.11 mmol. |
| 6 | Liquid | NaOH (for pH adjustment) c | |
| a. Compartments are numbered 1-7, with compartment #7 located closest to pack fill position #2. | |||
| b. Nominal value at manufacture. | |||
| c. See Precautions. |
Precautions: Compartment #6 contains 75µL of 10 N NaOH; avoid contact; skin irritant; rinse contacted area with water. Comply with OSHA'S Bloodborne Pathogens Standard while handling biological samples (29 CFR 1910.1039).
Used packs contain human body fluids; handle with appropriate care.
FOR IN VITRO DIAGNOSTIC USE
Mixing and Diluting:
Mixing and diluting are automatically performed by the ACA ® discrete clinical analyzer. The sample cup must contain sufficient quantity to accommodate the sample volume plus the “dead volume”; precise cup filling is not required.
| Analyzer | Standard | Microsystem | ||
|---|---|---|---|---|
| Dead | Total | Dead | Total | |
| II, III | 120 | 3000 | 10 | 500 |
| IV, SX | 120 | 3000 | 30 | 500 |
| V | 90 | 3000 | 10 | 500 |
Storage of Unprocessed Packs: Store at 2-8 °C. Do not freeze. Do not expose to temperatures above 35 °C or to direct sunlight.
Expiration: Refer to EXPIRATION DATE on the tray label.
Specimen Collection: Serum or urine can be collected and stored by normal procedures. 2
Known Interfering Substances 3
• Serum Protein Influence—Serum protein levels exert a direct influence on the CREA assay. The following should be taken into account when this method is used for urine samples and when it is calibrated:
Aqueous creatinine standards or urine specimens will give CREA results depressed by approximately 0.7 mg/dL [62 µmol/L] d and will be less precise than samples containing more than 3 g/dL [30 g/L] protein.
All urine specimens should be diluted with an albumin solution to give a final protein concentration of at least 3 g/dL [30 g/L]. Du Pont Enzyme Diluent (Cat. #790035-901) may be used for this purpose.
• High concentration of endrogenous bilirubin (>20 mg/dL [>342 µmol/L]) will give depressed CREA results (average depression 0.8 mg/dL [71 µmol/L]). 4
• Grossly hemolyzed (hemoglobin >100 mg/dL [>62 µmol/L]) or visibly lipemic specimens may cause falsely elevated CREA results. 5 6
• The following cephalosporin antibiotics do not interfere with the CREA method when present at the concentrations indicated. Systematic inaccuracies (bias) due to these substances are less than or equal to 0.1 mg/dL [8.84 µmol/L] at CREA concentrations of approximately 1 mg/dL [88 µmol/L].
| Antibiotic | Peak serum level 7 8 9 | Drug concentration | ||
|---|---|---|---|---|
| mg/dL | [mmol/L] | mg/dL | [mmol/L] | |
| Cephaloridine | 1.4 | 0.3 | 25 | 6.0 |
| Cephalexin | 0.6-2.0 | 0.2-0.6 | 25 | 7.2 |
| Cephamandole | 1.3-2.5 | 0.3-0.5 | 25 | 4.9 |
| Cephapirin | 2.0 | D0.4 | 25 | 5.6 |
| Cephradine | 1.5-2.0 | 0.4-0.6 | 25 | 7.1 |
| Cefazolin | 2.5-5.0 | 0.55-1.1 | 50 | 11.0 |
• The following cephalosporin antibiotics have been shown to affect CREA results when present at the indicated concentrations. System inaccuracies (bias) due to these substances are greater that 0.1 mg/dL [8.84 µmol/L] at CREA concentrations of:
| Antibiotic | Peak serum level 8 10 | Drug concentration | |||
|---|---|---|---|---|---|
| mg/dL | [mmol/L] | mg/dL | [mmol/L] | Effect | |
| Cephalothin | 1-6 | 0.2-1.5 | 100 | 25.2 | ↓20-25% |
| Cephoxitin | 2.0 | 0.5 | 5.0 | 1.2 | ↑35-40% |
• The single wavelength measurement used in this method eliminates interference from chromophores whose 510 nm absorbance is constant throughout the measurement period.
• Each laboratory should determine the acceptability of its own blood collection tubes and serum separation products. Variations in these products may exist between manufacturers and, at times, from lot to lot.
d. Systeme International d'unites (S.I. Units) are in brackets.
Procedure:
| Item | II, III Du Pont Cat. No. | IV, SX Du Pont Cat. No. | V Du Pont Cat. No. |
|---|---|---|---|
| ACA ® CREA Analytical Test Pack | 701976901 | 701976901 | 701976901 |
| Sample System Kit or | 710642901 | 710642901 | 713697901 |
| Micro Sample System Kit and | 702694901 | 710356901 | NA |
| Micro Sample System Holders | 702785000 | NA | NA |
| DYLUX ® Photosensitive | |||
| Printer Paper | 700036000 | NA | NA |
| Thermal Printer Paper | NA | 710639901 | 713645901 |
| Du Pont Purified Water | 704209901 | 710615901 | 710815901 |
| Cell Wash Solution | 701864901 | 710664901 | 710864901 |
Test Steps: The operator need only load the sample kit and appropriate test pack(s) into a properly prepared ACA ® discrete clinical analyzer. It automatically advances the pack(s) through the test steps and prints a result(s). See the Instrument Manual of the ACA ® analyzer for details of mechanical travel of the test pack(s).
Preset Creatinine (CREA)—Test Conditions
• Sample Volume: 200 µL
• Diluent: Purified Water
• Temperature: 37.0 ±0.1 °C
• Reaction Period: 29 seconds
• Type of Measurement: Rate
• Measurement Period: 17.07 seconds
• Wavelength: 510 nm
• Units: mg/dL [µmol/L]
CALIBRATION: The general calibration procedure is described in the Calibration/Verification chapter of the Manuals.
The following information should be considered when calibrating the CREA method.
e
f
g
• Suggested Calibration Levels: 1,5,20, mg/mL [88, 442, 1768 µmol/L].
• Calibration Scheme: 3 levels, 3 packs per level.
• Frequency: Each new pack lot. Every 3 months for any one pack lot.
e. For the results in S.I. units [µmol/L] the conversion factory is 88.4.
f. Refer to the Creatinine Standard Preparation and Calibration Procedure available on request from a Du Pont Representative.
g. If the Du Pont Chemistry Controls are being used, prepare them according to the instructions on the product insert sheets.
| Item | ACA ® II analyzer | ACA ® III, IV, SX, V analyzer |
|---|---|---|
| Count by | One (1) [Five (5)] | NA |
| Decimal Point | 0.0 mg/dL | 000.0 mg/dL |
| Location | [000.0 µmol/L] | [000 µmol/L] |
| Assigned Starting | 999.8 | −1.000 E1 |
| Point or Offset C o | [9823.] | [−8.840 E2] |
| Scale Factor or Assigned | 0.2000 mg/dL/count h | 2.004 E-1 h |
| Linear Term C 1 h | [0.3536 µmol/L/count] | [1.772E1] |
h. The preset scale factor (linear term) was derived from the molar absorptivity of the indicator and is based on an absorbance to activity relationship (sensitivity) of 0.596 (mA/min)/(U/L). Due to small differences in filters and electronic components between instruments, the actual scale factor (linear term) may differ slightly from that given above.
Quality Control: Two types of quality control procedures are recommended:
• General Instrument Check. Refer to the Filter Balance Procedure and the Absorbance Test Method described in the ACA Analyzer Instrument Manual. Refer also to the ABS Test Methodology literature.
• Creatinine Method Check. At least once daily run a CREA test on a solution of known creatinine activity such as an assayed control or calibration standard other than that used to calibrate the CREA method. For further details review the Quality Assurance Section of the Chemistry Manual. The result obtained should fall within acceptable limits defined by the day-to-day variability of the system as measured in the user's laboratory. (See SPECIFIC PERFORMANCE CHARACTERISTICS for guidance.) If the result falls outside the laboratory's acceptable limits, follow the procedure outlined in the Chemistry Troubleshooting Section of the Chemistry Manual.
A possible system malfunction is indicated when analysis of a sample with five consecutive test packs gives the following results:
| Level | SD |
|---|---|
| 1 mg/dL | >0.15 mg/dL |
| [88 µmol/L] | [>13 µmol/L] |
| 20 mg/dL | >0.68 mg/dL |
| [1768 µmol/L] | [>60 µmol/L] |
Refer to the procedure outlined in the Trouble Shooting Section of the Manual.
Results: The ACA ® analyzer automatically calculates and prints the CREA result in mg/dL [µmol/L].
Limitation of Procedure: Results >20 mg/dL [1768 µmol/L]:
• Dilute with suitable protein base diluent. Reassay. Correct for diluting before reporting.
The reporting system contains error messages to warn the operator of specific malfunctions. Any report slip containing a letter code or word immediately following the numerical value should not be reported. Refer to the Manual for the definition of error codes.
Reference Interval
| Serum: 11 i | |
|---|---|
| Males | 0.8-1.3 md/dL [71-115 µmol/L] |
| Females | 0.6-1.0 md/dL [53-88 µmol/L] |
| Urine: 12 | |
| Males | 0.6-2.5 g/24 hr [53-221 mmol/24 hr] |
| Females | 0.6-1.5 g/24 hr [53-133 mmol/24 hr] |
i. Reference interval data obtained from 200 apparently healthy individuals (71 males, 129 females) between the ages of 19 and 72.
Each laboratory should establish its own reference intervals for CREA as performed on the analyzer.
Specific Performance Characteristics j
| Material | Mean | Standard deviation (% CV) | |
|---|---|---|---|
| Within-run | Between-day | ||
| Lyophilized | 1.3 | 0.05 (3.7) | 0.05 (3.7) |
| Control | [115] | [4.4] | [4.4] |
| Lyophilized | 20.6 | 0.12 (0.6) | 0.37 (1.8) |
| Control | [1821] | [10.6] | [32.7] |
| Comparative method | Slope | Intercept | Correlation coefficient | n |
|---|---|---|---|---|
| Autoanalyzer ® | 1.03 | 0.03[2.7] | 0.997 | 260 |
j. All specific performance characteristics tests were run after normal recommended equipment quality control checks were performed (see Instrument Manual).
k. Specimens at each level were analyzed in duplicate for twenty days. The within-run and between-day standard deviations were calculated by the analysis of variance method.
l. Model equation for regression statistics is:
Assay Range m
0.0-20.0 mg/dl
[0-1768 µmol]
m. See REPRODUCIBILITY for method performance within the assay range.
Analytical Specificity
See KNOWN INTERFERING SUBSTANCES section for details.
Bibliography
1 Larsen, K, Clin Chem Acta 41, 209 (1972).
2 Tietz, NW, Fundamentals of Clinical Chemistry, W. B. Saunders Co., Philadelphia, PA, 1976, pp 47-52, 1211.
3 Supplementary information pertaining to the effects of various drugs and patient conditions on in vivo or in vitro diagnostic levels can be found in “Drug Interferences with Clinical Laboratory Tests,” Clin. Chem 21 (5) (1975), and “Effects of Disease on Clinical Laboratory Tests,” Clin Chem, 26 (4) 1D-476D (1980).
4 Watkins, R. Fieldkamp, SC, Thibert, RJ, and Zak, B, Clin Chem, 21, 1002 (1975).
5 Kawas, EE, Richards, AH, and Bigger, R, An Evaluation of a Kinetic Creatinine Test for the Du Pont ACA, Du Pont Company, Wilmington, DE (February 1973). (Reprints available from DuPont Company, Diagnostic Systems)
6 Westgard, JO, Effects of Hemolysis and Lipemia on ACA Creatinine Method, 0.200 µL, Sample Size, Du Pont Company, Wilmington, DE (October 1972).
7 Physicians' Desk Reference, Medical Economics Company, 33 Edition, 1979.
8 Henry, JB, Clinical Diagnosis and Management by Laboratory Methods, W.B. Saunders Co., Philadelphia, PA 1979, Vol. III.
9 Krupp, MA, Tierney, LM Jr., Jawetz, E, Roe, RI, Camargo, CA, Physicians Handbook, Lange Medical Publications, Los Altos, CA, 1982 pp 635-636.
10 Sarah, AJ, Koch, TR, Drusano, GL, Celoxitin Falsely Elevates Creatinine Levels, JAMA 247, 205-206 (1982).
11 Gadsden, RH, and Phelps, CA, A Normal Range Study of Amylase in Urine and Serum on the Du Pont ACA, Du Pont Company, Wilmington, DE (March 1978). (Reprints available from DuPont Company, Diagnostic Systems)
12 Dicht, JJ, Reference Intervals for Serum Amylase and Urinary Creatinine on the Du Pont ACA ® Discrete Clinical Analyzer, Du Pont Company, Wilmington, DE (November 1984).
Attachment 3—Analysis of Creatinine for the Normalization of Cadmium and Beta-2-Microglobulin Concentrations in Urine (OSLTC Procedure).
Matrix: Urine.
Target concentration: 1.1 g/L (this amount is representative of creatinine concentrations found in urine).
Procedure: A 1.0 mL aliquot of urine is passed through a C18 SEP-PAK ® (Waters Associates). Approximately 30 mL of HPLC (high performance liquid chromatography) grade water is then run through the SEP-PAK. The resulting solution is diluted to volume in a 100-mL volumetric flask and analyzed by HPLC using an ultraviolet (UV) detector.
Special requirements: After collection, samples should be appropriately stabilized for cadmium (Cd) analysis by using 10% high purity (with low Cd background levels) nitric acid (exactly 1.0 mL of 10% nitric acid per 10 mL of urine) or stabilized for Beta-2-Microglobulin (B2M) by taking to pH 7 with dilute NaOH (exactly 1.0 mL of 0.11 N NaOH per 10 mL of urine). If not immediately analyzed, the samples should be frozen and shipped by overnight mail in an insulated container.
Dated: January 1992.
David B. Armitage,
Duane Lee,
Chemists.
Organic Service Branch II, OSHA Technical Center, Salt Lake City, Utah
1. General Discussion
1.1 Background
1.1.1. History of procedure
Creatinine has been analyzed by several methods in the past. The earliest methods were of the wet chemical type. As an example, creatinine reacts with sodium picrate in basic solution to form a red complex, which is then analyzed colorimetrically (Refs. 5.1. and 5.2.).
Since industrial hygiene laboratories will be analyzing for Cd and B2M in urine, they will be normalizing those concentrations to the concentration of creatinine in urine. A literature search revealed several HPLC methods (Refs. 5.3., 5.4., 5.5. and 5.6.) for creatinine in urine and because many industrial hygiene laboratories have HPLC equipment, it was desirable to develop an industrial hygiene HPLC method for creatinine in urine. The method of Hausen, Fuchs, and Wachter was chosen as the starting point for method development. SEP-PAKs were used for sample clarification and cleanup in this method to protect the analytical column. The urine aliquot which has been passed through the SEP-PAK is then analyzed by reverse-phase HPLC using ion-pair techniques.
This method is very similar to that of Ogata and Taguchi (Ref. 5.6.), except they used centrifugation for sample clean-up. It is also of note that they did a comparison of their HPLC results to those of the Jaffe method (a picric acid method commonly used in the health care industry) and found a linear relationship of close to 1:1. This indicates that either HPLC or colorimetric methods may be used to measure creatinine concentrations in urine.
1.1.2. Physical properties (Ref. 5.7.)
Molecular weight: 113.12
4
7
3
Chemical name: 2-amino-1,5-dihydro-1-methyl-4H-imidazol-4-one
CAS No.: 60-27-5
Melting point: 300 °C (decomposes)
Appearance: white powder
Solubility: soluble in water; slightly soluble in alcohol; practically insoluble in acetone, ether, and chloroform
Synonyms: 1-methylglycocyamidine, 1-methylhydantoin-2-imide
Structure: see Figure #1
1.2. Advantages
1.2.1. This method offers a simple, straightforward, and specific alternative method to the Jaffe method.
1.2.2. HPLC instrumentation is commonly found in many industrial hygiene laboratories.
2. Sample stabilization procedure
2.1. Apparatus
Metal-free plastic container for urine sample.
2.2. Reagents
2.2.1. Stabilizing Solution—
2.2.2. HPLC grade water
2.3. Technique
2.3.1. Stabilizing solution is added to the urine sample (see section 2.2.1.). The stabilizing solution should be such that for each 10 mL of urine, add exactly 1.0 mL of stabilizer solution. (Never add water or urine to acid or base. Always add acid or base to water or urine.) Exactly 1.0 mL of 0.11 N NaOH added to 10 mL of urine should result in a pH of 7. Or add 1.0 mL of 10% nitric acid to 10 mL of urine.
2.3.2. After sample collection seal the plastic bottle securely and wrap it with an appropriate seal. Urine samples should be frozen and then shipped by overnight mail (if shipping is necessary) in an insulated container. (Do not fill plastic bottle too full. This will allow for expansion of contents during the freezing process.)
2.4. The Effect of Preparation and Stabilization Techniques on Creatinine Concentrations
Three urine samples were prepared by making one sample acidic, not treating a second sample, and adjusting a third sample to pH 7. The samples were analyzed in duplicate by two different procedures. For the first procedure a 1.0 mL aliquot of urine was put in a 100-mL volumetric flask, diluted to volume with HPLC grade water, and then analyzed directly on an HPLC. The other procedure used SEP-PAKs. The SEP-PAK was rinsed with approximately 5 mL of methanol followed by approximately 10 mL of HPLC grade water and both rinses were discarded. Then, 1.0 mL of the urine sample was put through the SEP-PAK, followed by 30 mL of HPLC grade water. The urine and water were transferred to a 100-mL volumetric flask, diluted to volume with HPLC grade water, and analyzed by HPLC. These three urine samples were analyzed on the day they were obtained and then frozen. The results show that whether the urine is acidic, untreated or adjusted to pH 7, the resulting answer for creatinine is essentially unchanged. The purpose of stabilizing the urine by making it acidic or neutral is for the analysis of Cd or B2M respectively.
| Sample | w/o SEP-PAK g/L creatinine | with SEP-PAK g/L creatinine |
|---|---|---|
| Acid | 1.10 | 1.10 |
| Acid | 1.11 | 1.10 |
| Untreated | 1.12 | 1.11 |
| Untreated | 1.11 | 1.12 |
| pH 7 | 1.08 | 1.02 |
| pH 7 | 1.11 | 1.08 |
2.5. Storage
After 4 days and 54 days of storage in a freezer, the samples were thawed, brought to room temperature and analyzed using the same procedures as in section 2.4. The results of several days of storage show that the resulting answer of creatinine is essentially unchanged.
| Sample | 4 days | 54 days | ||
|---|---|---|---|---|
| w/o SEP-PAK g/L creatinine | with SEP-PAK g/L creatinine | w/o SEP-PAK g/L creatinine | with SEP-PAK g/L creatinine | |
| Acid | 1.09 | 1.09 | 1.08 | 1.09 |
| Acid | 1.10 | 1.10 | 1.09 | 1.10 |
| Acid | 1.09 | 1.09 | ||
| Untreated | 1.13 | 1.14 | 1.09 | 1.11 |
| Untreated | 1.15 | 1.14 | 1.10 | 1.10 |
| Untreated | 1.09 | 1.10 | ||
| pH 7 | 1.14 | 1.13 | 1.12 | 1.12 |
| pH 7 | 1.14 | 1.13 | 1.12 | 1.12 |
| pH 7 | 1.12 | 1.12 |
2.6. Interferences
None.
2.7. Safety precautions
2.7.1. Make sure samples are properly sealed and frozen before shipment to avoid leakage.
2.7.2. Follow the appropriate shipping procedures.
The following modified special safety precautions are based on those recommended by the Centers for Disease Control (CDC) (Ref. 5.8.). and OSHA's Bloodborne Pathogens standard (29 CFR 1910.1039).
2.7.3. Wear gloves, lab coat, and safety glasses while handling all human urine products. Disposable plastic, glass, and paper (pipet tips, gloves, etc.) that contact urine should be placed in a biohazard autoclave bag. These bags should be kept in appropriate containers until sealed and autoclaved. Wipe down all work surfaces with 10% sodium hypochlorite solution when work is finished.
2.7.4. Dispose of all biological samples and diluted specimens in a biohazard autoclave bag at the end of the analytical run.
2.7.5. Special care should be taken when handling and dispensing nitric acid. Always remember to add acid to water (or urine). Nitric acid is a corrosive chemical capable of severe eye and skin damage. Wear metal-free gloves, a lab coat, and safety glasses. If the nitric acid comes in contact with any part of the body, quickly wash with copious quantities of water for at least 15 minutes.
2.7.6. Special care should be taken when handling and dispensing NaOH. Always remember to add base to water (or urine). NaOH can cause severe eye and skin damage. Always wear the appropriate gloves, a lab coat, and safety glasses. If the NaOH comes in contact with any part of the body, quickly wash with copious quantities of water for at least 15 minutes.
3. Analytical procedure
3.1. Apparatus
3.1.1. A high performance liquid chromatograph equipped with pump, sample injector and UV detector.
3.1.2. A C18 HPLC column; 25 cm × 4.6 mm I.D.
3.1.3. An electronic integrator, or some other suitable means of determining analyte response.
3.1.4. Stripchart recorder.
3.1.5. C18 SEP-PAKs (Waters Associates) or equivalent.
3.1.6. Luer-lock syringe for sample preparation (5 mL or 10 mL).
3.1.7. Volumetric pipettes and flasks for standard and sample preparation.
3.1.8. Vacuum system to aid sample preparation (optional).
3.2. Reagents
3.2.1. Water, HPLC grade.
3.2.2. Methanol, HPLC grade.
3.2.3. PIC B-7 ® (Waters Associates) in small vials.
3.2.4. Creatinine, anhydrous, Sigma hemical Corp., purity not listed.
3.2.5. 1-Heptanesulfonic acid, sodium salt monohydrate.
3.2.6. Phosphoric acid.
3.2.7. Mobile phase. It can be prepared by mixing one vial of PIC B-7 into a 1 L solution of 50% methanol and 50% water. The mobile phase can also be made by preparing a solution that is 50% methanol and 50% water with 0.005M heptanesulfonic acid and adjusting the pH of the solution to 3.5 with phosphoric acid.
3.3. Standard preparation
3.3.1. Stock standards are prepared by weighing 10 to 15 mg of creatinine. This is transferred to a 25-mL volumetric flask and diluted to volume with HPLC grade water.
3.3.2. Dilutions to a working range of 3 to 35 µg/mL are made in either HPLC grade water or HPLC mobile phase (standards give the same detector response in either solution).
3.4. Sample preparation
3.4.1. The C18 SEP-PAK is connected to a Luer-lock syringe. It is rinsed with 5 mL HPLC grade methanol and then 10 mL of HPLC grade water. These rinses are discarded.
3.4.2. Exactly 1.0 mL of urine is pipetted into the syringe. The urine is put through the SEP-PAK into a suitable container using a vacuum system.
3.4.3. The walls of the syringe are rinsed in several stages with a total of approximately 30 mL of HPLC grade water. These rinses are put through the SEP-PAK into the same container. The resulting solution is transferred to a 100-mL volumetric flask and then brought to volume with HPLC grade water.
3.5. Analysis (conditions and hardware are those used in this evaluation.)
3.5.1. Instrument conditions
Column: Zorbax ® ODS, 5-6 µm particle size; 25 cm × 4.6 mm I.D.
Mobile phase: See Section 3.2.7.
Detector: Dual wavelength UV; 229 nm (primary) 254 nm (secondary)
Flow rate: 0.7 mL/ minute
Retention time: 7.2 minutes
Sensitivity: 0.05 AUFS
Injection volume: 20µl
3.5.2. Chromatogram (see Figure #2)
3.6. Interferences
3.6.1. Any compound that has the same retention time as creatinine and absorbs at 229 nm is an interference.
i.e.
3.7. Calculations
3.7.1. A calibration curve is constructed by plotting detector response versus standard concentration (See Figure #3).
3.7.2. The concentration of creatinine in a sample is determined by finding the concentration corresponding to its detector response. (See Figure #3).
3.7.3. The µg/mL creatinine from section 3.7.2. is then multiplied by 100 (the dilution factor). This value is equivalent to the micrograms of creatinine in the 1.0 mL stabilized urine aliquot or the milligrams of creatinine per liter of urine. The desired units, g/L, is determined by the following relationship:
3.7.4. The resulting value for creatinine is used to normalize the urinary concentration of the desired analyte (A) (Cd or B2M) by using the following formula.
Where A is the desired analyte. The protocol of reporting such normalized results is µg A/g creatinine.
3.8. Safety precautions See section 2.7.
4. Conclusions
The determination of creatinine in urine by HPLC is a good alternative to the Jaffe method for industrial hygiene laboratories. Sample clarification with SEP-PAKs did not change the amount of creatinine found in urine samples. However, it does protect the analytical column. The results of this creatinine in urine procedure are unaffected by the pH of the urine sample under the conditions tested by this procedure. Therefore, no special measures are required for creatinine analysis whether the urine sample has been stabilized with 10% nitric acid for the Cd analysis or brought to a pH of 7 with 0.11 N NaOH for the B2M analysis.
5. References
Anal. Chem.
J. Biol. Chem.
J. Clin. Chem. Clin. Biochem.
J. Liq. Chrom.
J. Chrom.
Industrial Health
5.7. “Merck Index”, 11th ed.; Windholz, Martha Ed.; Merck: Rahway, N.J., 1989; p 403.
“Determination of Cadmium in Urine by Graphite Furnace Atomic Absorption Spectrometry with Zeeman Background Correction.”,
[57 FR 42389, Sept. 14, 1992, as amended at 57 FR 49272, Oct. 30, 1992; 58 FR 21781, Apr. 23, 1993; 61 FR 5508, Feb. 13, 1996; 63 FR 1288, Jan. 8, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June 8, 2011; 77 FR 17781, Mar. 26, 2012; 84 FR 21477, May 14, 2019; 85 FR 8732, Feb. 18, 2020]
Action level means an airborne concentration of benzene of 0.5 ppm calculated as an 8-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer whose duties require the person to enter a regulated area, or any person entering such an area as a designated representative of employees for the purpose of exercising the right to observe monitoring and measuring procedures under paragraph (l) of this section, or any other person authorized by the Act or regulations issued under the Act.
Benzene (C 6 H 6 ) (CAS Registry No. 71-43-2) means liquefied or gaseous benzene. It includes benzene contained in liquid mixtures and the benzene vapors released by these liquids. It does not include trace amounts of unreacted benzene contained in solid materials.
Bulk wholesale storage facility means a bulk terminal or bulk plant where fuel is stored prior to its delivery to wholesale customers.
Container means any barrel, bottle, can, cylinder, drum, reaction vessel, storage tank, or the like, but does not include piping systems.
Day means any part of a calendar day.
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment which may or does result in an unexpected significant release of benzene.
Employee exposure means exposure to airborne benzene which would occur if the employee were not using respiratory protective equipment.
Regulated area means any area where airborne concentrations of benzene exceed or can reasonably be expected to exceed, the permissible exposure limits, either the 8-hour time weighted average exposure of 1 ppm or the short-term exposure limit of 5 ppm for 15 minutes.
Vapor control system means any equipment used for containing the total vapors displaced during the loading of gasoline, motor fuel or other fuel tank trucks and the displacing of these vapors through a vapor processing system or balancing the vapor with the storage tank. This equipment also includes systems containing the vapors displaced from the storage tank during the unloading of the tank truck which balance the vapors back to the tank truck.
The employer shall assure that no employee is exposed to an airborne concentration of benzene in excess of one part of benzene per million parts of air (1 ppm) as an 8-hour time-weighted average.
The employer shall assure that no employee is exposed to an airborne concentration of benzene in excess of five (5) ppm as averaged over any 15 minute period.
Monitoring shall be accurate, to a confidence level of 95 percent, to within plus or minus 25 percent for airborne concentrations of benzene.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Personal protective clothing and equipment shall be worn where appropriate to prevent eye contact and limit dermal exposure to liquid benzene. Protective clothing and equipment shall be provided by the employer at no cost to the employee and the employer shall assure its use where appropriate. Eye and face protection shall meet the requirements of 29 CFR 1910.133.
A complete blood count including a leukocyte count with differential, a quantitative thrombocyte count, hematocrit, hemoglobin, erythrocyte count and erythrocyte indices (MCV, MCH, MCHC). The results of these tests shall be reviewed by the examining physician.
The employer shall provide the following information to the examining physician:
general. Chemical manufacturers, importers, distributors and employers shall comply with all requirements of the Hazard Communication Standard (HCS) (§ 1910.1200) for benzene.
DANGER
BENZENE
MAY CAUSE CANCER
HIGHLY FLAMMABLE LIQUID AND VAPOR
DO NOT SMOKE
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
BENZENE
CANCER HAZARD
FLAMMABLE—NO SMOKING
AUTHORIZED PERSONNEL ONLY
RESPIRATOR REQUIRED
DANGER
CONTAINS BENZENE
CANCER HAZARD
The employer shall comply with the requirements involving transfer of records as set forth in 29 CFR 1910.1020(h).
The employer shall provide affected employees, or their designated representatives, an opportunity to observe the measuring or monitoring of employee exposure to benzene conducted pursuant to paragraph (e) of this section.
When observation of the measuring or monitoring of employee exposure to benzene requires entry into areas where the use of protective clothing and equipment or respirators is required, the employer shall provide the observer with personal protective clothing and equipment or respirators required to be worn by employees working in the area, assure the use of such clothing and equipment or respirators, and require the observer to comply with all other applicable safety and health procedures.
The information contained in Appendices A, B, C, and D is not intended, by itself, to create any additional obligations not otherwise imposed or to detract from any existing obligations.
Appendix A to § 1910.1028—Substance Safety Data Sheet, Benzene
I. Substance Identification
A. Substance: Benzene.
B. Permissible Exposure: Except as to the use of gasoline, motor fuels and other fuels subsequent to discharge from bulk terminals and other exemptions specified in § 1910.1028(a)(2):
1. Airborne: The maximum time-weighted average (TWA) exposure limit is 1 part of benzene vapor per million parts of air (1 ppm) for an 8-hour workday and the maximum short-term exposure limit (STEL) is 5 ppm for any 15-minute period.
2. Dermal: Eye contact shall be prevented and skin contact with liquid benzene shall be limited.
C. Appearance and odor: Benzene is a clear, colorless liquid with a pleasant, sweet odor. The odor of benzene does not provide adequate warning of its hazard.
II. Health Hazard Data
A. Ways in which benzene affects your health. Benzene can affect your health if you inhale it, or if it comes in contact with your skin or eyes. Benzene is also harmful if you happen to swallow it.
B. Effects of overexposure. 1. Short-term (acute) overexposure: If you are overexposed to high concentrations of benzene, well above the levels where its odor is first recognizable, you may feel breathless, irritable, euphoric, or giddy; you may experience irritation in eyes, nose, and respiratory tract. You may develop a headache, feel dizzy, nauseated, or intoxicated. Severe exposures may lead to convulsions and loss of consciousness.
2. Long-term (chronic) exposure. Repeated or prolonged exposure to benzene, even at relatively low concentrations, may result in various blood disorders, ranging from anemia to leukemia, an irreversible, fatal disease. Many blood disorders associated with benzene exposure may occur without symptoms.
III. Protective Clothing and Equipment
A. Respirators. Respirators are required for those operations in which engineering controls or work practice controls are not feasible to reduce exposure to the permissible level. However, where employers can document that benzene is present in the workplace less than 30 days a year, respirators may be used in lieu of engineering controls. If respirators are worn, they must have joint Mine Safety and Health Administration and the National Institute for Occupational Safety and Health (NIOSH) seal of approval, and cartridge or canisters must be replaced before the end of their service life, or the end of the shift, whichever occurs first. If you experience difficulty breathing while wearing a respirator, you may request a positive pressure respirator from your employer. You must be thoroughly trained to use the assigned respirator, and the training will be provided by your employer.
B. Protective Clothing. You must wear appropriate protective clothing (such as boots, gloves, sleeves, aprons, etc.) over any parts of your body that could be exposed to liquid benzene.
C. Eye and Face Protection. You must wear splash-proof safety goggles if it is possible that benzene may get into your eyes. In addition, you must wear a face shield if your face could be splashed with benzene liquid.
IV. Emergency and First Aid Procedures
A. Eye and face exposure. If benzene is splashed in your eyes, wash it out immediately with large amounts of water. If irritation persists or vision appears to be affected see a doctor as soon as possible.
B. Skin exposure. If benzene is spilled on your clothing or skin, remove the contaminated clothing and wash the exposed skin with large amounts of water and soap immediately. Wash contaminated clothing before you wear it again.
C. Breathing. If you or any other person breathes in large amounts of benzene, get the exposed person to fresh air at once. Apply artificial respiration if breathing has stopped. Call for medical assistance or a doctor as soon as possible. Never enter any vessel or confined space where the benzene concentration might be high without proper safety equipment and at least one other person present who will stay outside. A life line should be used.
D. Swallowing. If benzene has been swallowed and the patient is conscious, do not induce vomiting. Call for medical assistance or a doctor immediately.
V. Medical Requirements
If you are exposed to benzene at a concentration at or above 0.5 ppm as an 8-hour time-weighted average, or have been exposed at or above 10 ppm in the past while employed by your current employer, your employer is required to provide a medical examination and history and laboratory tests within 60 days of the effective date of this standard and annually thereafter. These tests shall be provided without cost to you. In addition, if you are accidentally exposed to benzene (either by ingestion, inhalation, or skin/eye contact) under emergency conditions known or suspected to constitute toxic exposure to benzene, your employer is required to make special laboratory tests available to you.
VI. Observation of Monitoring
Your employer is required to perform measurements that are representative of your exposure to benzene and you or your designated representative are entitled to observe the monitoring procedure. You are entitled to observe the steps taken in the measurement procedure, and to record the results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and equipment are required to be worn, you or your representative must also be provided with, and must wear the protective clothing and equipment.
VII. Access to Records
You or your representative are entitled to see the records of measurements of your exposure to benzene upon written request to your employer. Your medical examination records can be furnished to yourself, your physician or designated representative upon request by you to your employer.
VIII. Precautions for Safe Use, Handling and Storage
Benzene liquid is highly flammable. It should be stored in tightly closed containers in a cool, well ventilated area. Benzene vapor may form explosive mixtures in air. All sources of ignition must be controlled. Use nonsparking tools when opening or closing benzene containers. Fire extinguishers, where provided, must be readily available. Know where they are located and how to operate them. Smoking is prohibited in areas where benzene is used or stored. Ask your supervisor where benzene is used in your area and for additional plant safety rules.
Appendix B to § 1910.1028—Substance Technical Guidelines, Benzene
I. Physical and Chemical Data
A. Substance identification.
1. Synonyms: Benzol, benzole, coal naphtha, cyclohexatriene, phene, phenyl hydride, pyrobenzol. (Benzin, petroleum benzin and Benzine do not contain benzene).
2. Formula: C 6 H 6 (CAS Registry Number: 71-43-2)
B. Physical data.
1. Boiling Point (760 mm Hg); 80.1 °C (176 °F)
2. Specific Gravity (water = 1): 0.879
3. Vapor Density (air = 1): 2.7
4. Melting Point: 5.5 °C (42 °F)
5. Vapor Pressure at 20 °C (68 °F): 75 mm Hg
6. Solubility in Water:.06%
7. Evaporation Rate (ether = 1): 2.8
8. Appearance and Odor: Clear, colorless liquid with a distinctive sweet odor.
II. Fire, Explosion, and Reactivity Hazard Data
A. Fire.
1. Flash Point (closed cup): −11 °C (12 °F)
2. Autoignition Temperature: 580 °C (1076 °F)
3. Flammable limits in Air. % by Volume: Lower: 1.3%, Upper: 7.5%
4. Extinguishing Media: Carbon dioxide, dry chemical, or foam.
5. Special Fire-Fighting procedures: Do not use solid stream of water, since stream will scatter and spread fire. Fine water spray can be used to keep fire-exposed containers cool.
6. Unusual fire and explosion hazards: Benzene is a flammable liquid. Its vapors can form explosive mixtures. All ignition sources must be controlled when benzene is used, handled, or stored. Where liquid or vapor may be released, such areas shall be considered as hazardous locations. Benzene vapors are heavier than air; thus the vapors may travel along the ground and be ignited by open flames or sparks at locations remote from the site at which benzene is handled.
7. Benzene is classified as a 1 B flammable liquid for the purpose of conforming to the requirements of 29 CFR 1910.106. A concentration exceeding 3,250 ppm is considered a potential fire explosion hazard. Locations where benzene may be present in quantities sufficient to produce explosive or ignitable mixtures are considered Class I Group D for the purposes of conforming to the requirements of 29 CFR 1910.309.
B. Reactivity.
1. Conditions contributing to instability: Heat.
2. Incompatibility: Heat and oxidizing materials.
3. Hazardous decomposition products: Toxic gases and vapors (such as carbon monoxide).
III. Spill and Leak Procedures
A. Steps to be taken if the material is released or spilled. As much benzene as possible should be absorbed with suitable materials, such as dry sand or earth. That remaining must be flushed with large amounts of water. Do not flush benzene into a confined space, such as a sewer, because of explosion danger. Remove all ignition sources. Ventilate enclosed places.
B. Waste disposal method. Disposal methods must conform to other jurisdictional regulations. If allowed, benzene may be disposed of: (a) By absorbing it in dry sand or earth and disposing in a sanitary landfill; (b) if small quantities, by removing it to a safe location from buildings or other combustible sources, pouring it in dry sand or earth and cautiously igniting it; and (c) if large quantities, by atomizing it in a suitable combustion chamber.
IV. Miscellaneous Precautions
A. High exposure to benzene can occur when transferring the liquid from one container to another. Such operations should be well ventilated and good work practices must be established to avoid spills.
B. Use non-sparking tools to open benzene containers which are effectively grounded and bonded prior to opening and pouring.
C. Employers must advise employees of all plant areas and operations where exposure to benzene could occur. Common operations in which high exposures to benzene may be encountered are: the primary production and utilization of benzene, and transfer of benzene.
Appendix C to § 1910.1028—Medical Surveillance Guidelines for Benzene
I. Route of Entry
Inhalation; skin absorption.
II. Toxicology
Benzene is primarily an inhalation hazard. Systemic absorption may cause depression of the hematopoietic system, pancytopenia, aplastic anemia, and leukemia. Inhalation of high concentrations can affect central nervous system function. Aspiration of small amounts of liquid benzene immediately causes pulmonary edema and hemorrhage of pulmonary tissue. There is some absorption through the skin. Absorption may be more rapid in the case of abraded skin, and benzene may be more readily absorbed if it is present in a mixture or as a contaminant in solvents which are readily absorbed. The defatting action of benzene may produce primary irritation due to repeated or prolonged contact with the skin. High concentration are irritating to the eyes and the mucuous membranes of the nose, and respiratory tract.
III. Signs and Symptoms
Direct skin contact with benzene may cause erythema. Repeated or prolonged contact may result in drying, scaling dermatitis, or development of secondary skin infections. In addition, there is benzene absorption through the skin. Local effects of benzene vapor or liquid on the eye are slight. Only at very high concentrations is there any smarting sensation in the eye. Inhalation of high concentrations of benzene may have an initial stimulatory effect on the central nervous system characterized by exhilaration, nervous excitation, and/or giddiness, followed by a period of depression, drowsiness, or fatigue. A sensation of tightness in the chest accompanied by breathlessness may occur and ultimately the victim may lose consciousness. Tremors, convulsions and death may follow from respiratory paralysis or circulatory collapse in a few minutes to several hours following severe exposures.
The detrimental effect on the blood-forming system of prolonged exposure to small quantities of benzene vapor is of extreme importance. The hematopoietic system is the chief target for benzene's toxic effects which are manifested by alterations in the levels of formed elements in the peripheral blood. These effects have occurred at concentrations of benzene which may not cause irritation of mucous membranes, or any unpleasant sensory effects. Early signs and symptoms of benzene morbidity are varied, often not readily noticed and non-specific. Subjective complaints of headache, dizziness, and loss of appetite may precede or follow clinical signs. Rapid pulse and low blood pressure, in addition to a physical appearance of anemia, may accompany a subjective complaint of shortness of breath and excessive tiredness. Bleeding from the nose, gums, or mucous membranes, and the development of purpuric spots (small bruises) may occur as the condition progresses. Clinical evidence of leukopenia, anemia, and thrombocytopenia, singly or in combination, has been frequently reported among the first signs.
Bone marrow may appear normal, aplastic, or hyperplastic, and may not, in all situations, correlate with peripheral blood forming tissues. Because of variations in the susceptibility to benzene morbidity, there is no “typical” blood picture. The onset of effects of prolonged benzene exposure may be delayed for many months or years after the actual exposure has ceased and identification or correlation with benzene exposure must be sought out in the occupational history.
IV. Treatment of Acute Toxic Effects
Remove from exposure immediately. Make sure you are adequately protected and do not risk being overcome by fumes. Give oxygen or artificial resuscitation if indicated. Flush eyes, wash skin if contaminated and remove all contaminated clothing. Symptoms of intoxication may persist following severe exposures. Recovery from mild exposures is usually rapid and complete.
V. Surveillance and Preventive Considerations
A. General
The principal effects of benzene exposure which form the basis for this regulation are pathological changes in the hematopoietic system, reflected by changes in the peripheral blood and manifesting clinically as pancytopenia, aplastic anemia, and leukemia. Consequently, the medical surveillance program is designed to observe, on a regular basis, blood indices for early signs of these effects, and although early signs of leukemia are not usually available, emerging diagnostic technology and innovative regimes make consistent surveillance for leukemia, as well as other hematopoietic effects, essential.
Initial examinations are to be provided within 60 days of the effective date of this standard, or at the time of initial assignment, and periodic examinations annually thereafter. There are special provisions for medical tests in the event of hematologic abnormalities or for emergency situations.
The blood values which require referral to a hematologist or internist are noted in the standard in paragraph (i)(5). The standard specifies that blood abnormalities that persist must be referred “unless the physician has good reason to believe such referral is unnecessary” (paragraph (i)(5)). Examples of conditions that could make a referral unnecessary despite abnormal blood limits are iron or folate deficiency, menorrhagia, or blood loss due to some unrelated medical abnormality.
Symptoms and signs of benzene toxicity can be non-specific. Only a detailed history and appropriate investigative procedures will enable a physician to rule out or confirm conditions that place the employee at increased risk. To assist the examining physician with regard to which laboratory tests are necessary and when to refer an employee to the specialist, OSHA has established the following guidelines.
B. Hematology Guidelines
A minimum battery of tests is to be performed by strictly standardized methods.
1. Red cell, white cell, platelet counts, white blood cell differential, hematacrit and red cell indices must be performed by an accredited laboratory. The normal ranges for the red cell and white cell counts are influenced by altitude, race, and sex, and therefore should be determined by the accredited laboratory in the specific area where the tests are performed.
Either a decline from an absolute normal or an individual's base line to a subnormal value or a rise to a supra-normal value, are indicative of potential toxicity, particularly if all blood parameters decline. The normal total white blood count is approximately 7,200/mm 3 plus or minus 3,000. For cigarette smokers the white count may be higher and the upper range may be 2,000 cells higher than normal for the laboratory. In addition, infection, allergies and some drugs may raise the white cell count. The normal platelet count is approximately 250,000 with a range of 140,000 to 400,000. Counts outside this range should be regarded as possible evidence of benzene toxicity.
Certain abnormalities found through routine screening are of greater significance in the benzene-exposed worker and require prompt consultation with a specialist, namely:
a. Thrombocytopenia.
b. A trend of decreasing white cell, red cell, or platelet indices in an individual over time is more worrisome than an isolated abnormal finding at one test time. The importance of trend highlights the need to compare an individual's test results to baseline and/or previous periodic tests.
c. A constellation or pattern of abnormalities in the different blood indices is of more significance than a single abnormality. A low white count not associated with any abnormalities in other cell indices may be a normal statistical variation, whereas if the low white count is accompanied by decreases in the platelet and/or red cell indices, such a pattern is more likely to be associated with benzene toxicity and merits thorough investigation.
Anemia, leukopenia, macrocytosis or an abnormal differential white blood cell count should alert the physician to further investigate and/or refer the patient if repeat tests confirm the abnormalities. If routine screening detects an abnormality, follow-up tests which may be helpful in establishing the etiology of the abnormality are the peripheral blood smear and the reticulocyte count.
The extreme range of normal for reticulocytes is 0.4 to 2.5 percent of the red cells, the usual range being 0.5 to 1.2 percent of the red cells, but the typical value is in the range of 0.8 to 1.0 percent. A decline in reticulocytes to levels of less than 0.4 percent is to be regarded as possible evidence (unless another specific cause is found) of benzene toxicity requiring accelerated surveillance. An increase in reticulocyte levels to about 2.5 percent may also be consistent with (but is not as characteristic of) benzene toxicity.
2. An important diagnostic test is a careful examination of the peripheral blood smear. As with reticulocyte count the smear should be with fresh uncoagulated blood obtained from a needle tip following venipuncture or from a drop of earlobe blood (capillary blood). If necessary, the smear may, under certain limited conditions, be made from a blood sample anticoagulated with EDTA (but never with oxalate or heparin). When the smear is to be prepared from a specimen of venous blood which has been collected by a commercial Vacutainer ® type tube containing neutral EDTA, the smear should be made as soon as possible after the venesection. A delay of up to 12 hours is permissible between the drawing of the blood specimen into EDTA and the preparation of the smear if the blood is stored at refrigerator (not freezing) temperature.
3. The minimum mandatory observations to be made from the smear are:
a. The differential white blood cell count.
b. Description of abnormalities in the appearance of red cells.
c. Description of any abnormalities in the platelets.
d. A careful search must be made throughout of every blood smear for immature white cells such as band forms (in more than normal proportion, i.e., over 10 percent of the total differential count), any number of metamyelocytes, myelocytes or myeloblasts. Any nucleate or multinucleated red blood cells should be reported. Large “giant” platelets or fragments of megakaryocytes must be recognized.
An increase in the proportion of band forms among the neutrophilic granulocytes is an abnormality deserving special mention, for it may represent a change which should be considered as an early warning of benzene toxicity in the absence of other causative factors (most commonly infection). Likewise, the appearance of metamyelocytes, in the absence of another probable cause, is to be considered a possible indication of benzene-induced toxicity.
An upward trend in the number of basophils, which normally do not exceed about 2.0 percent of the total white cells, is to be regarded as possible evidence of benzene toxicity. A rise in the eosinophil count is less specific but also may be suspicious of toxicity if the rises above 6.0 percent of the total white count.
The normal range of monocytes is from 2.0 to 8.0 percent of the total white count with an average of about 5.0 percent. About 20 percent of individuals reported to have mild but persisting abnormalities caused by exposure to benzene show a persistent monocytosis. The findings of a monocyte count which persists at more than 10 to 12 percent of the normal white cell count (when the total count is normal) or persistence of an absolute monocyte count in excess of 800/mm 3 should be regarded as a possible sign of benzene-induced toxicity.
A less frequent but more serious indication of benzene toxicity is the finding in the peripheral blood of the so-called “pseudo” (or acquired) Pelger-Huet anomaly. In this anomaly many, or sometimes the majority, of the neutrophilic granulocytes possess two round nuclear segements—less often one or three round segments—rather than three normally elongated segments. When this anomaly is not hereditary, it is often but not invariably predictive of subsequent leukemia. However, only about two percent of patients who ultimately develop acute myelogenous leukemia show the acquired Pelger-Huet anomaly. Other tests that can be administered to investigate blood abnormalities are discussed below; however, such procedures should be undertaken by the hematologist.
An uncommon sign, which cannot be detected from the smear, but can be elicited by a “sucrose water test” of peripheral blood, is transient paroxysmal nocturnal hemoglobinuria (PNH), which may first occur insidiously during a period of established aplastic anemia, and may be followed within one to a few years by the appearance of rapidly fatal acute myelogenous leukemia. Clinical detection of PNH, which occurs in only one or two percent of those destined to have acute myelogenous leukemia, may be difficult; if the “sucrose water test” is positive, the somewhat more definitive Ham test, also known as the acid-serum hemolysis test, may provide confirmation.
e. Individuals documented to have developed acute myelogenous leukemia years after initial exposure to benzene may have progressed through a preliminary phase of hematologic abnormality. In some instances pancytopenia ( i.e., a lowering in the counts of all circulating blood cells of bone marrow origin, but not to the extent implied by the term “aplastic anemia”) preceded leukemia for many years. Depression of a single blood cell type or platelets may represent a harbinger of aplasia or leukemia. The finding of two or more cytopenias, or pancytopenia in a benzene-exposed individual, must be regarded as highly suspicious of more advanced although still reversible, toxicity. “Pancytopenia” coupled with the appearance of immature cells (myelocytes, myeloblasts, erythroblasts, etc.), with abnormal cells (pseudo Pelger-Huet anomaly, atypical nuclear heterochromatin, etc.), or unexplained elevations of white blood cells must be regarded as evidence of benzene overexposure unless proved otherwise. Many severely aplastic patients manifested the ominous finding of 5-10 percent myeloblasts in the marrow, occasional myeloblasts and myelocytes in the blood and 20-30% monocytes. It is evident that isolated cytopenias, pancytopenias, and even aplastic anemias induced by benzene may be reversible and complete recovery has been reported on cessation of exposure. However, since any of these abnormalities is serious, the employee must immediately be removed from any possible exposure to benzene vapor. Certain tests may substantiate the employee's prospects for progression or regression. One such test would be an examination of the bone marrow, but the decision to perform a bone marrow aspiration or needle biopsy is made by the hematologist.
The findings of basophilic stippling in circulating red blood cells (usually found in 1 to 5% of red cells following marrow injury), and detection in the bone marrow of what are termed “ringed sideroblasts” must be taken seriously, as they have been noted in recent years to be premonitory signs of subsequent leukemia.
Recently peroxidase-staining of circulating or marrow neutrophil granulocytes, employing benzidine dihydrochloride, have revealed the disappearance of, or diminution in, peroxidase in a sizable proportion of the granulocytes, and this has been reported as an early sign of leukemia. However, relatively few patients have been studied to date. Granulocyte granules are normally strongly peroxidase positive. A steady decline in leukocyte alkaline phosphatase has also been reported as suggestive of early acute leukemia. Exposure to benzene may cause an early rise in serum iron, often but not always associated with a fall in the reticulocyte count. Thus, serial measurements of serum iron levels may provide a means of determining whether or not there is a trend representing sustained suppression of erythropoiesis.
Measurement of serum iron, determination of peroxidase and of alkaline phosphatase activity in peripheral granulocytes can be performed in most pathology laboratories. Peroxidase and alkaline phosphatase staining are usually undertaken when the index of suspecion for leukemia is high.
Appendix D to § 1910.1028—Sampling and Analytical Methods for Benzene Monitoring and Measurement Procedures
Measurements taken for the purpose of determining employee exposure to benzene are best taken so that the representative average 8-hour exposure may be determined from a single 8-hour sample or two (2) 4-hour samples. Short-time interval samples (or grab samples) may also be used to determine average exposure level if a minimum of five measurements are taken in a random manner over the 8-hour work shift. Random sampling means that any portion of the work shift has the same change of being sampled as any other. The arithmetic average of all such random samples taken on one work shift is an estimate of an employee's average level of exposure for that work shift. Air samples should be taken in the employee's breathing zone (air that would most nearly represent that inhaled by the employee). Sampling and analysis must be performed with procedures meeting the requirements of the standard.
There are a number of methods available for monitoring employee exposures to benzene. The sampling and analysis may be performed by collection of the benzene vaptor or charcoal absorption tubes, with subsequent chemical analysis by gas chromatography. Sampling and analysis may also be performed by portable direct reading instruments, real-time continuous monitoring systems, passive dosimeters or other suitable methods. The employer has the obligation of selecting a monitoring method which meets the accuracy and precision requirements of the standard under his unique field conditions. The standard requires that the method of monitoring must have an accuracy, to a 95 percent confidence level, of not less than plus or minus 25 percent for concentrations of benzene greater than or equal to 0.5 ppm.
The OSHA Laboratory modified NIOSH Method S311 and evaluated it at a benzene air concentration of 1 ppm. A procedure for determining the benzene concentration in bulk material samples was also evalauted. This work, reported in OSHA Laboratory Method No. 12, includes the following two analytical procedures:
I. OSHA Method 12 for Air Samples
Analyte: Benzene
Matrix: Air
Procedure: Adsorption on charcoal, desorption with carbon disulfide, analysis by GC.
Detection limit: 0.04 ppm
Recommended air volume and sampling rate: 10L to 0.2 L/min.
1. Principle of the Method.
1.1 A known volume of air is drawn through a charcoal tube to trap the organic vapors present.
1.2. The charcoal in the tube is transferred to a small, stoppered vial, and the anlyte is desorbed with carbon disulfide.
1.3. An aliquot of the desorbed sample is injected into a gas chromatograph.
1.4 The area of the resulting peak is determined and compared with areas obtained from standards.
2. Advantages and disadvantages of the method.
2.1 The sampling device is small, portable, and involved no liquids. Interferences are minimal, and most of those which do occur can be eliminated by altering chromatographic conditions. The samples are analyzed by means of a quick, instrumental method.
2.2 The amount of sample which can be taken is limited by the number of milligrams that the tube will hold before overloading. When the sample value obtained for the backup section of the charcoal tube exceeds 25 percent of that found on the front section, the possibility of sample loss exists.
3. Apparatus.
3.1 A calibrated personal sampling pump whose flow can be determined within ±5 percent at the recommended flow rate.
3.2. Charcoal tubes: Glass with both ends flame sealed, 7 cm long with a 6-mm O.D. and a 4-mm I.D., containing 2 sections of 20/40 mesh activated charcoal separated by a 2-mm portion of urethane foam. The activated charcoal is prepared from coconut shells and is fired at 600 °C prior to packing. The adsorbing section contains 100 mg of charcoal, the back-up section 50 mg. A 3-mm portion of urethane foam is placed between the outlet end of the tube and the back-up section. A plug of silanized glass wool is placed in front of the adsorbing section. The pressure drop across the tube must be less than one inch of mercury at a flow rate of 1 liter per minute.
3.3. Gas chromatograph equipped with a flame ionization detector.
3.4. Column (10-ft × 1/8 -in stainless steel) packed with 80/100 Supelcoport coated with 20 percent SP 2100, 0.1 percent CW 1500.
3.5. An electronic integrator or some other suitable method for measuring peak area.
3.6. Two-milliliter sample vials with Teflon-lined caps.
3.7. Microliter syringes: 10-microliter (10-µL syringe, and other convenient sizes for making standards, 1-µL syringe for sample injections.
3.8. Pipets: 1.0 mL delivery pipets
3.9. Volumetric flasks: convenient sizes for making standard solutions.
4. Reagents.
4.1. Chromatographic quality carbon disulfide (CS 2 ). Most commercially available carbon disulfide contains a trace of benzene which must be removed. It can be removed with the following procedure:
Heat under reflux for 2 to 3 hours, 500 mL of carbon disulfide, 10 mL concentrated sulfuric acid, and 5 drops of concentrated nitric acid. The benzene is converted to nitrobenzene. The carbon disulfide layer is removed, dried with anhydrous sodium sulfate, and distilled. The recovered carbon disulfide should be benzene free. (It has recently been determined that benzene can also be removed by passing the carbon disulfide through 13x molecular sieve).
4.2. Benzene, reagent grade.
4.3. p-Cymene, reagent grade, (internal standard).
4.4. Desorbing reagent. The desorbing reagent is prepared by adding 0.05 mL of p-cymene per milliliter of carbon disulfide. (The internal standard offers a convenient means correcting analytical response for slight inconsistencies in the size of sample injections. If the external standard technique is preferred, the internal standard can be eliminated).
4.5. Purified GC grade helium, hydrogen and air.
5. Procedure.
5.1. Cleaning of equipment. All glassware used for the laboratory analysis should be properly cleaned and free of organics which could interfere in the analysis.
5.2. Calibration of personal pumps. Each pump must be calibrated with a representative charcoal tube in the line.
5.3. Collection and shipping of samples.
5.3.1. Immediately before sampling, break the ends of the tube to provide an opening at least one-half the internal diameter of the tube (2 mm).
5.3.2. The smaller section of the charcoal is used as the backup and should be placed nearest the sampling pump.
5.3.3. The charcoal tube should be placed in a vertical position during sampling to minimize channeling through the charcoal.
5.3.4 Air being sampled should not be passed through any hose or tubing before entering the charcoal tube.
5.3.5. A sample size of 10 liters is recommended. Sample at a flow rate of approximately 0.2 liters per minute. The flow rate should be known with an accuracy of at least ±5 percent.
5.3.6. The charcoal tubes should be capped with the supplied plastic caps immediately after sampling.
5.3.7. Submit at least one blank tube (a charcoal tube subjected to the same handling procedures, without having any air drawn through it) with each set of samples.
5.3.8. Take necessary shipping and packing precautions to minimize breakage of samples.
5.4. Analysis of samples.
5.4.1. Preparation of samples. In preparation for analysis, each charcoal tube is scored with a file in front of the first section of charcoal and broken open. The glass wool is removed and discarded. The charcoal in the first (larger) section is transferred to a 2-ml vial. The separating section of foam is removed and discarded; the second section is transferred to another capped vial. These two sections are analyzed separately.
5.4.2. Desorption of samples. Prior to analysis, 1.0 mL of desorbing solution is pipetted into each sample container. The desorbing solution consists of 0.05 µL internal standard per mL of carbon disulfide. The sample vials are capped as soon as the solvent is added. Desorption should be done for 30 minutes with occasional shaking.
5.4.3. GC conditions. Typical operating conditions for the gas chromatograph are:
1.30 mL/min (60 psig) helium carrier gas flow.
2.30 mL/min (40 psig) hydrogen gas flow to detector.
3.240 mL/min (40 psig) air flow to detector.
4.150 °C injector temperature.
5.250 °C detector temperature.
6.100 °C column temperature.
5.4.4. Injection size. 1 µL.
5.4.5. Measurement of area. The peak areas are measured by an electronic integrator or some other suitable form of area measurement.
5.4.6. An internal standard procedure is used. The integrator is calibrated to report results in ppm for a 10 liter air sample after correction for desorption efficiency.
5.5. Determination of desorption efficiency.
5.5.1. Importance of determination. The desorption efficiency of a particular compound can vary from one laboratory to another and from one lot of chemical to another. Thus, it is necessary to determine, at least once, the percentage of the specific compound that is removed in the desorption process, provided the same batch of charcoal is used.
5.5.2. Procedure for determining desorption efficiency. The reference portion of the charcoal tube is removed. To the remaining portion, amounts representing 0.5X, 1X, and 2X and (X represents target concentration) based on a 10 L air sample are injected into several tubes at each level. Dilutions of benzene with carbon disulfide are made to allow injection of measurable quantities. These tubes are then allowed to equilibrate at least overnight. Following equilibration they are analyzed following the same procedure as the samples. Desorption efficiency is determined by dividing the amount of benzene found by amount spiked on the tube.
6. Calibration and standards. A series of standards varying in concentration over the range of interest is prepared and analyzed under the same GC conditions that will be used on the samples. A calibration curve is prepared by plotting concentration (µg/mL) versus peak area.
7. Calculations. Benzene air concentration can be calculated from the following equation:
3
Where:
A = µg/mL benzene, obtained from the calibration curve
B = desorption volume (1 mL)
C = Liters of air sampled
D = desorption efficiency
The concentration in mg/m 3 can be converted to ppm (at 25° and 760 mm) with following equation:
3
Where:
24.46 = molar volume of an ideal gas
25 °C and 760 mm
78.11 = molecular weight of benzene
8. Backup Data.
8.1 Detection limit—Air Samples.
The detection limit for the analytical procedure is 1.28 ng with a coefficient of variation of 0.023 at this level. This would be equivalent to an air concentration of 0.04 ppm for a 10 L air sample. This amount provided a chromatographic peak that could be identifiable in the presence of possible interferences. The detection limit data were obtained by making 1 µL injections of a 1.283 µg/mL standard.
| Injection | Area Count | |
|---|---|---|
| 1 | 655.4 | |
| 2 | 617.5 | |
| 3 | 662.0 | X = 640.2 |
| 4 | 641.1 | SD = 14.9 |
| 5 | 636.4 | CV = 0.023 |
| 6 | 629.2 |
8.2. Pooled coefficient of variation—Air Samples. The pooled coefficient of variation for the analytical procedure was determined by 1 µL replicate injections of analytical standards. The standards were 16.04, 32.08, and 64.16 µg/mL, which are equivalent to 0.5, 1.0, and 2.0 ppm for a 10 L air sample respectively.
| Injection | Area Counts | ||
|---|---|---|---|
| 0.5 ppm | 1.0 ppm | 2.0 ppm | |
| 1 | 3996.5 | 8130.2 | 16481 |
| 2 | 4059.4 | 8235.6 | 16493 |
| 3 | 4052.0 | 8307.9 | 16535 |
| 4 | 4027.2 | 8263.2 | 16609 |
| 5 | 4046.8 | 8291.1 | 16552 |
| 6 | 4137.9 | 8288.8 | 16618 |
| X = | 4053.3 | 8254.0 | 16548.3 |
| SD= | 47.2 | 62.5 | 57.1 |
| CV = | 0.0116 | 0.0076 | 0.0034 |
| C V = 0.008 |
8.3. Storage data—Air Samples
Samples were generated at 1.03 ppm benzene at 80% relative humidity, 22 °C, and 643 mm. All samples were taken for 50 minutes at 0.2 L/min. Six samples were analyzed immediately and the rest of the samples were divided into two groups by fifteen samples each. One group was stored at refrigerated temperature of −25 °C, and the other group was stored at ambient temperature (approximately 23 °C). These samples were analyzed over a period of fifteen days. The results are tabulated below.
| Day analyzed | Refrigerated | Ambient |
|---|---|---|
| 0 | 97.4 98.7 98.9 | 97.4 98.7 98.9 |
| 0 | 97.1 100.6 100.9 | 97.1 100.6 100.9 |
| 2 | 95.8 96.4 95.4 | 95.4 96.6 96.9 |
| 5 | 93.9 93.7 92.4 | 92.4 94.3 94.1 |
| 9 | 93.6 95.5 94.6 | 95.2 95.6 96.6 |
| 13 | 94.3 95.3 93.7 | 91.0 95.0 94.6 |
| 15 | 96.8 95.8 94.2 | 92.9 96.3 95.9 |
8.4. Desorption data.
Samples were prepared by injecting liquid benzene onto the A section of charcoal tubes. Samples were prepared that would be equivalent to 0.5, 1.0, and 2.0 ppm for a 10 L air sample.
| Sample | 0.5 ppm | 1.0 ppm | 2.0 ppm |
|---|---|---|---|
| 1 | 99.4 | 98.8 | 99.5 |
| 2 | 99.5 | 98.7 | 99.7 |
| 3 | 99.2 | 98.6 | 99.8 |
| 4 | 99.4 | 99.1 | 100.0 |
| 5 | 99.2 | 99.0 | 99.7 |
| 6 | 99.8 | 99.1 | 99.9 |
| X = | 99.4 | 98.9 | 99.8 |
| SD= | 0.22 | 0.21 | 0.18 |
| CV = | 0.0022 | 0.0021 | 0.0018 |
| X = 99.4 |
8.5. Carbon disulfide.
Carbon disulfide from a number of sources was analyzed for benzene contamination. The results are given in the following table. The benzene contamiant can be removed with the procedures given in section 4.1.
| Sample | µg Benzene/mL | ppm equivalent (for 10 L air sample) |
|---|---|---|
| Aldrich Lot 83017 | 4.20 | 0.13 |
| Baker Lot 720364 | 1.01 | 0.03 |
| Baker Lot 822351 | 1.01 | 0.03 |
| Malinkrodt Lot WEMP | 1.74 | 0.05 |
| Malinkrodt Lot WDSJ | 5.65 | 0.18 |
| Malinkrodt Lot WHGA | 2.90 | 0.09 |
| Treated CS 2 |
II. OSHA Laboratory Method No. 12 for Bulk Samples
Analyte: Benzene.
Matrix: Bulk Samples.
Procedure: Bulk Samples are analyzed directly by high performance liquid chromatography (HPLC).
Detection limits: 0.01% by volume.
1. Principle of the method.
1.1. An aliquot of the bulk sample to be analyzed is injected into a liquid chromatograph.
1.2. The peak area for benzene is determined and compared to areas obtained from standards.
2. Advantages and disadvantages of the method.
2.1. The analytical procedure is quick, sensitive, and reproducible.
2.2. Reanalysis of samples is possible.
2.3. Interferences can be circumvented by proper selection of HPLC parameters.
2.4. Samples must be free of any particulates that may clog the capillary tubing in the liquid chromatograph. This may require distilling the sample or clarifying with a clarification kit.
3. Apparatus.
3.1. Liquid chromatograph equipped with a UV detector.
3.2. HPLC Column that will separate benzene from other components in the bulk sample being analyzed. The column used for validation studies was a Waters uBondapack C18, 30 cm × 3.9 mm.
3.3. A clarification kit to remove any particulates in the bulk if necessary.
3.4. A micro-distillation apparatus to distill any samples if necessary.
3.5. An electronic integrator or some other suitable method of measuring peak areas.
3.6. Microliter syringes—10 µL syringe and other convenient sizes for making standards. 10 µL syringe for sample injections.
3.7. Volumetric flasks, 5 mL and other convenient sizes for preparing standards and making dilutions.
4. Reagents.
4.1. Benzene, reagent grade.
4.2. HPLC grade water, methyl alcohol, and isopropyl alcohol.
5. Collection and shipment of samples.
5.1. Samples should be transported in glass containers with Teflon-lined caps.
5.2. Samples should not be put in the same container used for air samples.
6. Analysis of samples.
6.1. Sample preparation.
If necessary, the samples are distilled or clarified. Samples are analyzed undiluted. If the benzene concentration is out of the working range, suitable dilutions are made with isopropyl alcohol.
6.2. HPLC conditions.
The typical operating conditions for the high performance liquid chromatograph are:
1. Mobile phase—Methyl alcohol/water, 50/50
1. Analytical wavelength—254 nm
3. Injection size—10 µL
6.3. Measurement of peak area and calibration.
Peak areas are measured by an integrator or other suitable means. The integrator is calibrated to report results % in benzene by volume.
7. Calculations.
Since the integrator is programmed to report results in % benzene by volume in an undiluted sample, the following equation is used:
% Benzene by Volume = A × B
Where:
A = % by volume on report
B = Dilution Factor
8. Backup Data.
8.1. Detection limit—Bulk Samples.
The detection limit for the analytical procedure for bulk samples is 0.88 µg, with a coefficient of variation of 0.019 at this level. This amount provided a chromatographic peak that could be identifiable in the presence of possible interferences. The detection limit date were obtained by making 10 µL injections of a 0.10% by volume standard.
| Injection | Area Count | |
|---|---|---|
| 1 | 45386 | |
| 2 | 44214 | |
| 3 | 43822 | X = 44040.1 |
| 4 | 44062 | SD = 852.5 |
| 6 | 42724 | CV = 0.019 |
8.2. Pooled coefficient of variation—Bulk Samples.
The pooled coefficient of variation for analytical procedure was determined by 50 µL replicate injections of analytical standards. The standards were 0.01, 0.02, 0.04, 0.10, 1.0, and 2.0% benzene by volume.
| Injection No. | 0.01 | 0.02 | 0.04 | 0.10 | 1.0 | 2.0 |
|---|---|---|---|---|---|---|
| 1 | 45386 | 84737 | 166097 | 448497 | 4395380 | 9339150 |
| 2 | 44241 | 84300 | 170832 | 441299 | 4590800 | 9484900 |
| 3 | 43822 | 83835 | 164160 | 443719 | 4593200 | 9557580 |
| 4 | 44062 | 84381 | 164445 | 444842 | 4642350 | 9677060 |
| 5 | 44006 | 83012 | 168398 | 442564 | 4646430 | 9766240 |
| 6 | 42724 | 81957 | 173002 | 443975 | 4646260 | |
| X = | 44040.1 | 83703.6 | 167872 | 444149 | 4585767 | 9564986 |
| SD = | 852.5 | 1042.2 | 3589.8 | 2459.1 | 96839.3 | 166233 |
| CV = | 0.0194 | 0.0125 | 0.0213 | 0.0055 | 0.0211 | 0.0174 |
| C V = | 0.017 |
[52 FR 34562, Sept. 11, 1987, as amended at 54 FR 24334, June 7, 1989; 61 FR 5508, Feb. 13, 1996; 63 FR 1289, Jan. 8, 1998; 63 FR 20099, Apr. 23, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16673, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June 8, 2011; 77 FR 17781, Mar. 26, 2012]
This section applies to the control of employee exposure to coke oven emissions, except that this section shall not apply to working conditions with regard to which other Federal agencies exercise statutory authority to prescribe or enforce standards affecting occupational safety and health.
For the purpose of this section:
Authorized person means any person specifically authorized by the employer whose duties require the person to enter a regulated area, or any person entering such an area as a designated representative of employees for the purpose of exercising the opportunity to observe monitoring and measuring procedures under paragraph (n) of this section.
Beehive oven means a coke oven in which the products of carbonization other than coke are not recovered, but are released into the ambient air.
Coke oven means a retort in which coke is produced by the destructive distillation or carbonization of coal.
Coke oven battery means a structure containing a number of slot-type coke ovens.
Coke oven emissions means the benzene-soluble fraction of total particulate matter present during the destructive distillation or carbonization of coal for the production of coke.
Director means the Director, National Institute for Occupational Safety and Health, U.S. Department of Health, Education, and Welfare, or his or her designee.
Emergency means any occurance such as, but not limited to, equipment failure which is likely to, or does, result in any massive release of coke oven emissions.
Existing coke oven battery means a battery in operation or under construction on January 20, 1977, and which is not a rehabilitated coke oven battery.
Rehabilitated coke oven battery means a battery which is rebuilt, overhauled, renovated, or restored such as from the pad up, after January 20, 1977.
Secretary means the Secretary of Labor, U.S. Department of Labor, or his or her designee.
Stage charging means a procedure by which a predetermined volume of coal in each larry car hopper is introduced into an oven such that no more than two hoppers are discharging simultaneously.
Sequential charging means a procedure, usually automatically timed, by which a predetermined volume of coal in each larry car hopper is introduced into an oven such that no more than two hoppers commence or finish discharging simultaneously although, at some point, all hoppers are discharging simultaneously.
Pipeline charging means any apparatus used to introduce coal into an oven which uses a pipe or duct permanently mounted onto an oven and through which coal is charged.
Green plush means coke which when removed from the oven results in emissions due to the presence of unvolatilized coal.
The employer shall assure that no employee in the regulated area is exposed to coke oven emissions at concentrations greater than 150 micrograms per cubic meter of air (150 µg/m 3 ), averaged over any 8-hour period.
Whenever there has been a production, process, or control change which may result in new or additional exposure to coke oven emissions, or whenever the employer has any other reason to suspect an increase in employee exposure, the employer shall repeat the monitoring and measurements required by paragraph (e)(1) of this section for those employees affected by such change or increase.
The employer shall use a method of monitoring and measurement which has an accuracy (with a confidence level of 95%) of not less than plus or minus 35% for concentrations of coke oven emissions greater than or equal to 150 µg/m 3.
The employer shall control employee exposure to coke oven emissions by the use of engineering controls, work practices and respiratory protection as follows:
The employer shall equip and operate existing coke oven batteries with all of the following engineering controls to control coke oven emissions during charging operations:
The employer shall equip and operate existing coke oven batteries with all of the following engineering controls to control coke oven emissions during coking operations;
The employer shall operate existing coke oven batteries with all of the following work practices to control coke oven emissions during the charging operation:
The employer shall operate existing coke oven batteries pursuant to a detailed written procedure established and implemented for the control of coke oven emissions during coking, consisting of at least the following elements:
The employer shall operate existing coke oven batteries with the following work practices to control coke oven emissions during pushing operations:
The employer shall operate existing coke oven batteries pursuant to a detailed written procedure of maintenance and repair established and implemented for the effective control of coke oven emissions consisting of the following elements:
Whenever an emergency occurs, the next coking cycle may not begin until the cause of the emergency is determined and corrected, unless the employer can establish that it is necessary to initiate the next coking cycle in order to determine the cause of the emergency.
The employer shall incorporate all written procedures and schedules required under this paragraph (f) in the information and training program required under paragraph (k) of this section and, where appropriate, post in the regulated area.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer must implement a respiratory protection program in accordance with § 1910.134(b) through (d) (except (d)(1)(iii)), and (f) through (m), which covers each employee required by this section to use a respirator.
Employers must select, and provide to employees, the appropriate respirators specified in paragraph (d)(3)(i)(A) of 29 CFR 1910.134; however, employers may use a filtering facepiece respirator only when it functions as a filter respirator for coke oven emissions particulates.
The employer shall provide and assure the use of appropriate protective clothing and equipment, such as but not limited to:
The employer shall provide clean change rooms equipped with storage facilities for street clothes and separate storage facilities for protective clothing and equipment whenever employees are required to wear protective clothing and equipment in accordance with paragraph (h)(1) of this section.
The employer shall provide lunchroom facilities which have a temperature controlled, positive pressure, filtered air supply, and which are readily accessible to employees working in the regulated area.
At the time of initial assignment to a regulated area or upon the institution of the medical surveillance program, the employer shall provide a medical examination for employees covered under paragraph (j)(1)(i) of this section including at least the following elements:
by 17-inch or other reasonably-sized standard film or digital posterior-anterior chest X-ray;
The employer shall provide the following information to the examining physician:
The employer shall include coke oven emissions in the program established to comply with the Hazard Communication Standard (HCS) (§ 1910.1200). The employer shall ensure that each employee has access to labels on containers of chemicals and substances associated with coke oven processes and to safety data sheets, and is trained in accordance with the provisions of HCS and paragraph (k) of this section. The employer shall ensure that at least the following hazard is addressed: Cancer.
DANGER
COKE OVEN EMISSIONS
MAY CAUSE CANCER
DO NOT EAT, DRINK OR SMOKE
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
WEAR RESPIRATORY PROTECTION IN THIS AREA
DANGER
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
NO SMOKING OR EATING
DANGER
RESPIRATOR REQUIRED
CONTAMINATED WITH COKE EMISSIONS
MAY CAUSE CANCER
DO NOT REMOVE DUST BY BLOWING OR SHAKING
CAUTION
CLOTHING CONTAMINATED WITH COKE EMISSIONS
DO NOT REMOVE DUST BY BLOWING OR SHAKING
The employer shall establish and maintain an accurate record of all measurements taken to monitor employee exposure to coke oven emissions required in paragraph (e) of this section.
The employer shall establish and maintain an accurate record for each employee subject to medical surveillance as required by paragraph (j) of this section.
The employer shall provide affected employees or their representatives an opportunity to observe any measuring or monitoring of employee exposure to coke oven emissions conducted pursuant to paragraph (e) of this section.
The information contained in the appendixes to this section is not intended, by itself, to create any additional obligations not otherwise imposed or to detract from any existing obligation.
Appendix A to § 1910.1029—Coke Oven Emissions Substance Information Sheet
i. Substance Identification
A. Substance: Coke Oven Emissions
B. Definition: The benzene-soluble fraction of total particulate matter present during the destructive distillation or carbonization of coal for the production of coke.
C. Permissible Exposure Limit: 150 micrograms per cubic meter of air determined as an average over an 8-hour period.
D. Regulated areas: Only employees authorized by your employer should enter a regulated area. The employer is required to designate the following areas as regulated areas: the coke oven battery, including topside and its machinery, pushside and its machinery, cokeside and its machinery, and the battery ends; the screening station; and the wharf; and the beehive ovens and their machinery.
ii. Health Hazard Data
Exposure to coke oven emissions is a cause of lung cancer, and kidney cancer, in humans. Although there have not been an excess number of skin cancer cases in humans, repeated skin contact with coke oven emissions should be avoided.
iii. Protective Clothing and Equipment
A. Respirators: Respirators will be provided by your employer for routine use if your employer is in the process of implementing engineering and work practice controls or where engineering and work practice controls are not feasible or insufficient to reduce exposure to or below the PEL. You must wear respirators for non-routine activities or in emergency situations where you are likely to be exposed to levels of coke oven emissions in excess of the permissible exposure limit. Until January 20, 1978, the routine wearing of respirators is voluntary. Until that date, if you choose not to wear a respirator you do not have to do so. You must still have your respirator with you and you must still wear it if you are near visible emissions. Since how well your respirator fits your face is very important, your employer is required to conduct fit tests to make sure the respirator seals properly when you wear it. These tests are simple and rapid and will be explained to you during your training sessions.
B. Protective clothing: Your employer is required to provide, and you must wear, appropriate, clean, protective clothing and equipment to protect your body from repeated skin contact with coke oven emissions and from the heat generated during the coking process. This clothing should include such items as jacket and pants and flame resistant gloves. Protective equipment should include face shield or vented goggles, protective helmets and safety shoes, insulated from hot surfaces where appropriate.
iv. Hygiene Facilities and Practices
You must not eat, drink, smoke, chew gum or tobacco, or apply cosmetics in the regulated area, except that drinking water is permitted. Your employer is required to provide lunchrooms and other areas for these purposes.
Your employer is required to provide showers, washing facilities, and change rooms. If you work in a regulated area, you must wash your face, and hands before eating. You must shower at the end of the work shift. Do not take used protective clothing out of the change rooms without your employer's permission. Your employer is required to provide for laundering or cleaning of your protective clothing.
v. Signs and Labels
Your employer is required to post warning signs and labels for your protection. Signs must be posted in regulated areas. The signs must warn that a cancer hazard is present, that only authorized employees may enter the area, and that no smoking or eating is allowed. In regulated areas where coke oven emissions are above the permissible exposure limit, the signs should also warn that respirators must be worn.
vi. Medical Examinations
If you work in a regulated area at least 30 days per year, your employer is required to provide you with a medical examination every year. The initial medical examination must include a medical history, a chest X-ray, pulmonary function test, weight comparison, skin examination, a urinalysis, and a urine cytology exam for early detection of urinary cancer. Periodic examinations shall include all tests required in the initial examination, except that (1) the x-ray is to be performed during initial examination only and (2) the urine cytologic test is to be performed only on those employees who are 45 years or older or who have worked for 5 or more years in the regulated area. The examining physician will provide a written opinion to your employer containing the results of the medical exams. You should also receive a copy of this opinion.
vii. Observation of Monitoring
Your employer is required to monitor your exposure to coke oven emissions and you are entitled to observe the monitoring procedure. You are entitled to receive an explanation of the measurement procedure, observe the steps taken in the measurement procedure, and to record the results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and equipment are required to be worn, you must also be provided with and must wear the protective clothing and equipment.
viii. Access to Records
You or your representative are entitled to records of your exposure to coke oven emissions upon request to your employer. Your medical examination records can be furnished to your physician upon request to your employer.
ix. Training and Education
Additional information on all of these items plus training as to hazards of coke oven emissions and the engineering and work practice controls associated with your job will also be provided by your employer.
Appendix B to § 1910.1029—Industrial Hygiene and Medical Surveillance Guidelines
i. industrial hygiene guidelines
A. Sampling (Benzene-Soluble Fraction Total Particulate Matter).
Samples collected should be full shift (at least 7-hour) samples. Sampling should be done using a personal sampling pump with pulsation damper at a flow rate of 2 liters per minute. Samples should be collected on 0.8 micrometer pore size silver membrane filters (37 mm diameter) preceded by Gelman glass fiber type A-E filters encased in three-piece plastic (polystyrene) field monitor cassettes. The cassette face cap should be on and the plug removed. The rotameter should be checked every hour to ensure that proper flow rates are maintained.
A minimum of three full-shift samples should be collected for each job classification on each battery, at least one from each shift. If disparate results are obtained for particular job classification, sampling should be repeated. It is advisable to sample each shift on more than one day to account for environmental variables (wind, precipitation, etc.) which may affect sampling. Differences in exposures among different work shifts may indicate a need to improve work practices on a particular shift. Sampling results from different shifts for each job classification should not be averaged. Multiple samples from same shift on each battery may be used to calculate an average exposure for a particular job classification.
B. Analysis.
1. All extraction glassware is cleaned with dichromic acid cleaning solution, rinsed with tap water, then dionized water, acetone, and allowed to dry completely. The glassware is rinsed with nanograde benzene before use. The Teflon cups are cleaned with benzene then with acetone.
2. Pre-weigh the 2 ml Teflon cups to one hundredth of a milligram (0.01 mg) on an autobalance AD 2 Tare weight of the cups is about 50 mg.
3. Place the silver membrane filter and glass fiber filter into a 15 ml test tube.
4. Extract with 5 ml of benzene for five minutes in an ultrasonic cleaner.
5. Filter the extract in 15 ml medium glass fritted funnels.
6. Rinse test tube and filters with two 1.5 ml aliquots of benzene and filter through the fritted glass funnel.
7. Collect the extract and two rinses in a 10 ml Kontes graduated evaporative concentrator.
8. Evaporate down to 1 ml while rinsing the sides with benzene.
9. Pipet 0.5 ml into the Teflon cup and evaporate to dryness in a vacuum oven at 40 °C for 3 hours.
10. Weigh the Teflon cup and the weight gain is due to the benzene soluble residue in half the Sample.
ii. medical surveillance guidelines
A. General. The minimum requirements for the medical examination for coke oven workers are given in the standard in paragraph (j) of this section. The initial examination is to be provided to all coke oven workers who work at least 30 days in the regulated area. The examination includes a 14″ by 17″ or other reasonably-sized standard film or digital posterior-anterior chest X-ray reading, pulmonary function tests (FVC and FEV 1 ), weight, urinalysis, skin examination, and a urinary cytologic examination. These tests are needed to serve as the baseline for comparing the employee's future test results. Periodic exams include all the elements of the initial exams, except that (1) the x-ray is to be performed during initial examination only and (2) the urine cytologic test is to be performed only on those employees who are 45 years or older or who have worked for 5 or more years in the regulated area. The examination contents are minimum requirements; additional tests such as lateral and oblique X-rays or additional pulmonary function tests may be performed if deemed necessary.
B. Pulmonary function tests.
Pulmonary function tests should be performed in a manner which minimizes subject and operator bias. There has been shown to be learning effects with regard to the results obtained from certain tests, such as FEV 1.0. Best results can be obtained by multiple trials for each subject. The best of three trials or the average of the last three of five trials may be used in obtaining reliable results. The type of equipment used (manufacturer, model, etc.) should be recorded with the results as reliability and accuracy varies and such information may be important in the evaluation of test results. Care should be exercised to obtain the best possible testing equipment.
[39 FR 23502, June 27, 1974, 41 FR 46784, Oct. 22, 1976, as amended at 42 FR 3304, Jan. 18, 1977; 45 FR 35283, May 23, 1980; 50 FR 37353, 37354, Sept. 13, 1985; 54 FR 24334, June 7, 1989; 61 FR 5508, Feb. 13, 1996; 63 FR 1290, Jan. 8, 1998; 63 FR 33468, June 18, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR 75585, Dec. 12, 2008; 76 FR 33608, June 8, 2011; 77 FR 17782, Mar. 26, 2012; 84 FR 21490, May 14, 2019]
This section applies to all occupational exposure to blood or other potentially infectious materials as defined by paragraph (b) of this section.
For purposes of this section, the following shall apply:
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, or designated representative.
Blood means human blood, human blood components, and products made from human blood.
Bloodborne Pathogens means pathogenic microorganisms that are present in human blood and can cause disease in humans. These pathogens include, but are not limited to, hepatitis B virus (HBV) and human immunodeficiency virus (HIV).
Clinical Laboratory means a workplace where diagnostic or other screening procedures are performed on blood or other potentially infectious materials.
Contaminated means the presence or the reasonably anticipated presence of blood or other potentially infectious materials on an item or surface.
Contaminated Laundry means laundry which has been soiled with blood or other potentially infectious materials or may contain sharps.
Contaminated Sharps means any contaminated object that can penetrate the skin including, but not limited to, needles, scalpels, broken glass, broken capillary tubes, and exposed ends of dental wires.
Decontamination means the use of physical or chemical means to remove, inactivate, or destroy bloodborne pathogens on a surface or item to the point where they are no longer capable of transmitting infectious particles and the surface or item is rendered safe for handling, use, or disposal.
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designated representative.
Engineering controls means controls (e.g., sharps disposal containers, self-sheathing needles, safer medical devices, such as sharps with engineered sharps injury protections and needleless systems) that isolate or remove the bloodborne pathogens hazard from the workplace.
Exposure Incident means a specific eye, mouth, other mucous membrane, non-intact skin, or parenteral contact with blood or other potentially infectious materials that results from the performance of an employee's duties.
Handwashing facilities means a facility providing an adequate supply of running potable water, soap, and single-use towels or air-drying machines.
Licensed Healthcare Professional is a person whose legally permitted scope of practice allows him or her to independently perform the activities required by paragraph (f) Hepatitis B Vaccination and Post-exposure Evaluation and Follow-up.
HBV means hepatitis B virus.
HIV means human immunodeficiency virus.
Needleless systems means a device that does not use needles for:
Occupational Exposure means reasonably anticipated skin, eye, mucous membrane, or parenteral contact with blood or other potentially infectious materials that may result from the performance of an employee's duties.
Other Potentially Infectious Materials means
semen, vaginal secretions, cerebrospinal fluid, synovial fluid, pleural fluid, pericardial fluid, peritoneal fluid, amniotic fluid, saliva in dental procedures, any body fluid that is visibly contaminated with blood, and all body fluids in situations where it is difficult or impossible to differentiate between body fluids;
Parenteral means piercing mucous membranes or the skin barrier through such events as needlesticks, human bites, cuts, and abrasions.
Personal Protective Equipment is specialized clothing or equipment worn by an employee for protection against a hazard. General work clothes (e.g., uniforms, pants, shirts or blouses) not intended to function as protection against a hazard are not considered to be personal protective equipment.
Production Facility means a facility engaged in industrial-scale, large-volume or high concentration production of HIV or HBV.
Regulated Waste means liquid or semi-liquid blood or other potentially infectious materials; contaminated items that would release blood or other potentially infectious materials in a liquid or semi-liquid state if compressed; items that are caked with dried blood or other potentially infectious materials and are capable of releasing these materials during handling; contaminated sharps; and pathological and microbiological wastes containing blood or other potentially infectious materials.
Research Laboratory means a laboratory producing or using research-laboratory-scale amounts of HIV or HBV. Research laboratories may produce high concentrations of HIV or HBV but not in the volume found in production facilities.
Sharps with engineered sharps injury protections means a nonneedle sharp or a needle device used for withdrawing body fluids, accessing a vein or artery, or administering medications or other fluids, with a built-in safety feature or mechanism that effectively reduces the risk of an exposure incident.
Source Individual means any individual, living or dead, whose blood or other potentially infectious materials may be a source of occupational exposure to the employee. Examples include, but are not limited to, hospital and clinic patients; clients in institutions for the developmentally disabled; trauma victims; clients of drug and alcohol treatment facilities; residents of hospices and nursing homes; human remains; and individuals who donate or sell blood or blood components.
Sterilize means the use of a physical or chemical procedure to destroy all microbial life including highly resistant bacterial endospores.
Universal Precautions is an approach to infection control. According to the concept of Universal Precautions, all human blood and certain human body fluids are treated as if known to be infectious for HIV, HBV, and other bloodborne pathogens.
Work Practice Controls means controls that reduce the likelihood of exposure by altering the manner in which a task is performed (e.g., prohibiting recapping of needles by a two-handed technique).
Universal precautions shall be observed to prevent contact with blood or other potentially infectious materials. Under circumstances in which differentiation between body fluid types is difficult or impossible, all body fluids shall be considered potentially infectious materials.
When there is occupational exposure, the employer shall provide, at no cost to the employee, appropriate personal protective equipment such as, but not limited to, gloves, gowns, laboratory coats, face shields or masks and eye protection, and mouthpieces, resuscitation bags, pocket masks, or other ventilation devices. Personal protective equipment will be considered “appropriate” only if it does not permit blood or other potentially infectious materials to pass through to or reach the employee's work clothes, street clothes, undergarments, skin, eyes, mouth, or other mucous membranes under normal conditions of use and for the duration of time which the protective equipment will be used.
The employer shall ensure that the employee uses appropriate personal protective equipment unless the employer shows that the employee temporarily and briefly declined to use personal protective equipment when, under rare and extraordinary circumstances, it was the employee's professional judgment that in the specific instance its use would have prevented the delivery of health care or public safety services or would have posed an increased hazard to the safety of the worker or co-worker. When the employee makes this judgement, the circumstances shall be investigated and documented in order to determine whether changes can be instituted to prevent such occurances in the future.
The employer shall ensure that appropriate personal protective equipment in the appropriate sizes is readily accessible at the worksite or is issued to employees. Hypoallergenic gloves, glove liners, powderless gloves, or other similar alternatives shall be readily accessible to those employees who are allergic to the gloves normally provided.
The employer shall clean, launder, and dispose of personal protective equipment required by paragraphs (d) and (e) of this standard, at no cost to the employee.
The employer shall repair or replace personal protective equipment as needed to maintain its effectiveness, at no cost to the employee.
Gloves shall be worn when it can be reasonably anticipated that the employee may have hand contact with blood, other potentially infectious materials, mucous membranes, and non-intact skin; when performing vascular access procedures except as specified in paragraph (d)(3)(ix)(D); and when handling or touching contaminated items or surfaces.
Masks in combination with eye protection devices, such as goggles or glasses with solid side shields, or chin-length face shields, shall be worn whenever splashes, spray, spatter, or droplets of blood or other potentially infectious materials may be generated and eye, nose, or mouth contamination can be reasonably anticipated.
Appropriate protective clothing such as, but not limited to, gowns, aprons, lab coats, clinic jackets, or similar outer garments shall be worn in occupational exposure situations. The type and characteristics will depend upon the task and degree of exposure anticipated.
Employers shall ensure that the worksite is maintained in a clean and sanitary condition. The employer shall determine and implement an appropriate written schedule for cleaning and method of decontamination based upon the location within the facility, type of surface to be cleaned, type of soil present, and tasks or procedures being performed in the area.
All regulated waste shall either be incinerated or decontaminated by a method such as autoclaving known to effectively destroy bloodborne pathogens.
and HBV research laboratories shall meet the following criteria:
and HBV production facilities shall meet the following criteria:
Additional training requirements for employees in HIV and HBV research laboratories and HIV and HBV production facilities are specified in paragraph (g)(2)(ix).
Following a report of an exposure incident, the employer shall make immediately available to the exposed employee a confidential medical evaluation and follow-up, including at least the following elements:
The employer shall obtain and provide the employee with a copy of the evaluating healthcare professional's written opinion within 15 days of the completion of the evaluation.
Medical records required by this standard shall be maintained in accordance with paragraph (h)(1) of this section.
The employer shall ensure that employee medical records required by paragraph (h)(1) are:
The employer shall comply with the requirements involving transfer of records set forth in 29 CFR 1910.1020(h).
The standard shall become effective on March 6, 1992.
Appendix A to Section 1910.1030—Hepatitis B Vaccine Declination (Mandatory)
I understand that due to my occupational exposure to blood or other potentially infectious materials I may be at risk of acquiring hepatitis B virus (HBV) infection. I have been given the opportunity to be vaccinated with hepatitis B vaccine, at no charge to myself. However, I decline hepatitis B vaccination at this time. I understand that by declining this vaccine, I continue to be at risk of acquiring hepatitis B, a serious disease. If in the future I continue to have occupational exposure to blood or other potentially infectious materials and I want to be vaccinated with hepatitis B vaccine, I can receive the vaccination series at no charge to me.
[56 FR 64175, Dec. 6, 1991, as amended at 57 FR 12717, Apr. 13, 1992; 57 FR 29206, July 1, 1992; 61 FR 5508, Feb. 13, 1996; 66 FR 5325, Jan. 18, 2001; 71 FR 16672, 16673, Apr. 3, 2006; 73 FR 75586, Dec. 12, 2008; 76 FR 33608, June 8, 2011; 76 FR 80740, Dec. 27, 2011; 77 FR 19934, Apr. 3, 2012]
For the purpose of this section:
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee;
Blow down means the general cleaning of a room or a part of a room by the use of compressed air.
Blow off means the use of compressed air for cleaning of short duration and usually for a specific machine or any portion of a machine.
Cotton dust means dust present in the air during the handling or processing of cotton, which may contain a mixture of many substances including ground up plant matter, fiber, bacteria, fungi, soil, pesticides, non-cotton plant matter and other contaminants which may have accumulated with the cotton during the growing, harvesting and subsequent processing or storage periods. Any dust present during the handling and processing of cotton through the weaving or knitting of fabrics, and dust present in other operations or manufacturing processes using raw or waste cotton fibers or cotton fiber byproducts from textile mills are considered cotton dust within this definition. Lubricating oil mist associated with weaving operations is not considered cotton dust.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Equivalent Instrument means a cotton dust sampling device that meets the vertical elutriator equivalency requirements as described in paragraph (d)(1)(iii) of this section.
Lint-free respirable cotton dust means particles of cotton dust of approximately 15 micrometers or less aerodynamic equivalent diameter;
Vertical elutriator cotton dust sampler or vertical elutriator means a dust sampler which has a particle size cut-off at approximately 15 micrometers aerodynamic equivalent diameter when operating at the flow rate of 7.4 ±0.2 liters of air per minute;
Waste processing means waste recycling (sorting, blending, cleaning and willowing) and garnetting.
Yarn manufacturing means all textile mill operations from opening to, but not including, slashing and weaving.
will issue a written opinion stating that an instrument is equivalent to a vertical elutriator cotton dust sampler if
Each employer who has a place of employment within the scope of paragraph (a)(1), (a)(4), or (a)(5) of this section shall conduct monitoring by obtaining measurements which are representative of the exposure of all employees to airborne concentrations of lint-free respirable cotton dust over an eight-hour period. The sampling program shall include at least one determination during each shift for each work area.
The employer shall institute engineering and work practice controls to reduce and maintain employee exposure to cotton dust at or below the permissible exposure limit specified in paragraph (c) of this section, except to the extent that the employer can establish that such controls are not feasible.
When mechanical ventilation is used to control exposure, measurements which demonstrate the effectiveness of the system to control exposure, such as capture velocity, duct velocity, or static pressure shall be made at reasonable intervals.
For employees who are required to use respirators by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Each employer shall, regardless of the level of employee exposure, immediately establish and implement a written program of work practices which shall minimize cotton dust exposure. The following shall be included were applicable:
The employer shall provide medical surveillance to each employee who is or may be exposed to cotton dust. For new employees, this examination shall be provided prior to initial assignment. The medical surveillance shall include at least the following:
The employer shall provide the following information to the examination physician:
DANGER
COTTON DUST
CAUSES DAMAGE TO LUNGS
WEAR RESPIRATORY PROTECTION IN THIS AREA
WARNING
COTTON DUST WORK AREA
MAY CAUSE ACUTE OR DELAYED
LUNG INJURY
RESPIRATORS
REQUIRED IN THIS AREA
Cotton, after it has been washed by the processes described in this paragraph, is exempt from all or parts of this section as specified if the requirements of this paragraph are met.
Medical grade (USP) cotton, cotton that has been scoured, bleached and dyed, and mercerized yarn shall be exempt from all provisions of this standard.
The handling or processing of cotton classed as “low middling light spotted or better” (color grade 52 or better and leaf grade code 5 or better according to the 1993 USDA classification system) shall be exempt from all provisions of the standard except the requirements of paragraphs (h) medical surveillance, (k)(2) through (4) recordkeeping—medical records, and Appendices B, C, and D of this section, if they have been washed on one of the following systems:
The handling and processing of cotton of grades lower than “low middling light spotted,” that has been washed as specified in paragraph (n)(4) of this section and has also been bleached, shall be exempt from all provisions of the standard except the requirements of paragraphs (c)(1)(ii) Permissible Exposure Limit, (d) Exposure Monitoring, (h) Medical Surveillance, (k) Recordkeeping, and Appendices B, C and D of this section.
If more than one grade of washed cotton is being handled or processed together, the requirements of the grade with the most stringent exposure limit, medical and monitoring requirements shall be followed.
Appendix A to § 1910.1043—Air Sampling and Analytical Procedures for Determining Concentrations of Cotton Dust
i. sampling locations
The sampling procedures must be designed so that samples of the actual dust concentrations are collected accurately and consistently and reflect the concentrations of dust at the place and time of sampling. Sufficient number of 6-hour area samples in each distinct work area of the plant should be collected at locations which provide representative samples of air to which the worker is exposed. In order to avoid filter overloading, sampling time may be shortened when sampling in dusty areas. Samples in each work area should be gathered simultaneously or sequentially during a normal operating period. The daily time-weighted average (TWA) exposure of each worker can then be determined by using the following formula:
Summation of hours spent in each location and the dust concentration in that location.
Total hours exposed
A time-weighted average concentration should be computed for each worker and properly logged and maintained on file for review.
ii. sampling equipment
The instrument selected for monitoring is the Lumsden-Lynch vertical elutriator. It should operate at a flow rate of 7.4±0.2 liters/minute.
The samplers should be cleaned prior to sampling. The pumps should be monitored during sampling.
A three-piece cassette constructed of polystyrene designed to hold a 37-mm diameter filter should be used. Care must be exercised to insure that an adequate seal exists between elements of the cassette.
The membrane filters used should be polyvinyl chloride with a 5-um pore size and 37-mm diameter. A support pad, commonly called a backup pad, should be used under the filter membrane in the field monitor cassette.
A balance sensitive to 10 micrograms should be used.
iii. instrument calibration procedure
Samplers shall be calibrated when first received from the factory, after repair, and after receiving any abuse. The samplers should be calibrated in the laboratory both before they are used in the field and after they have been used to collect a large number of field samples. The primary standard, such as a spirometer or other standard calibrating instruments such as a wet test meter or a large bubble meter or dry gas meter, should be used. Instructions for calibration with the wet test meter follow. If another calibration device is selected, equivalent procedures should be used:
Check the water level which should just touch the calibration point at the left side of the meter. If water level is low, add water 1-2 °F. warmer than room temperature of till point. Run the meter for 30 minutes before calibration;
The pointer on the meter should run clockwise and a pressure drop of not more than 1.0 inch of water indicated. If the pressure drop is greater than 1.0, disconnect and check the system;
iv. sampling procedure
Any difference in weight in the control filters would indicate that the procedure for handling sample filters may not be adequate and should be evaluated to ascertain the cause of the difference, whether and what necessary corrections must be made, and whether additional samples must be collected.
The cassette with samples should be collected, along with the appropriate number of blanks, and shipped to the analytical laboratory in a suitable container to prevent damage in transit.
Appendix B-II to § 1910.1043—Respiratory Questionnaire for Non-Textile Workers for the Cotton Industry
Appendix C to § 1910.1043—[Reserved]
Appendix D to § 1910.1043—Pulmonary Function Standards for Cotton Dust Standard
The spirometric measurements of pulmonary function shall conform to the following minimum standards, and these standards are not intended to preclude additional testing or alternate methods which can be determined to be superior.
I. Apparatus
a. The instrument shall be accurate to within ±50 milliliters or within ±3 percent of reading, whichever is greater.
b. 1. Instruments purchased on or before May 14, 2020 should be capable of measuring vital capacity from 0 to 7 liters BTPS
2. Instruments purchased after May 14, 2020 should be capable of measuring vital capacity from 0 to 8 liters BTPS.
c. The instrument shall have a low inertia and offer low resistance to airflow such that the resistance to airflow at 12 liters per second must be less than 1.5 cm H 2 O/(liter/sec).
d. The zero time point for the purpose of timing the FEV 1 shall be determined by extrapolating the steepest portion of the volume time curve back to the maximal inspiration volume (1, 2, 3, 4) or by an equivalent method.
e. 1. Instruments purchased on or before May 14, 2020 that incorporate measurements of airflow to determine volume shall conform to the same volume accuracy stated in paragraph (a) of this section I when presented with flow rates from at least 0 to 12 liters per second.
2. Instruments purchased after May 14, 2020 that incorporate measurements of airflow to determine volume shall conform to the same volume accuracy stated in paragraph (a) of this section I when presented with flow rates from at least 0 to 14 liters per second.
f. The instrument or user of the instrument must have a means of correcting volumes to body temperature saturated with water vapor (BTPS) under conditions of varying ambient spirometer temperatures and barometric pressures.
g. 1. Instruments purchased on or before May 14, 2020 shall provide a tracing or display of either flow versus volume or volume versus time during the entire forced expiration. A tracing or display is necessary to determine whether the patient has performed the test properly. The tracing must be stored and available for recall and must be of sufficient size that hand measurements may be made within the volume accuracy requirements of paragraph (a) of this section I. If a paper record is made it must have a paper speed of at least 2 cm/sec and a volume sensitivity of at least 10.0 mm of chart per liter of volume.
2. Instruments purchased after May 14, 2020 shall provide during testing a paper tracing or real-time display of flow versus volume and volume versus time for the entire forced expiration. Such a tracing or display is necessary to determine whether the worker has performed the test properly. Flow-volume and volume-time curves must be stored and available for recall. Real-time displays shall have a volume scale of at least 5 mm/L, a time scale of at least 10 mm/s, and a flow scale of at least 2.5 mm/L/s, when both flow-volume and volume-time displays are visible. If hand measurements will be made, paper tracings must be of sufficient size to allow those measurements to be made within the volume accuracy requirements of paragraph (a) of this section I. If a paper record is made it must have a paper speed of at least 2 cm/sec and a volume sensitivity of at least 10.0 mm of chart per liter of volume.
h. 1. Instruments purchased on or before May 14, 2020 shall be capable of accumulating volume for a minimum of 10 seconds and shall not stop accumulating volume before (i) the volume change for a 0.5-second interval is less than 25 milliliters, or (ii) the flow is less than 50 milliliters per second for a 0.5 second interval.
2. Instruments purchased after May 14, 2020 shall be capable of accumulating volume for a minimum of 15 seconds and shall not stop accumulating volume before the volume change for a 1-second interval is less than 25 milliliters.
i. The forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV 1 ) measurements shall comply with the accuracy requirements stated in paragraph (a) of this section. That is, they should be accurately measured to within ±50 ml or within ±3 percent of reading, whichever is greater.
j. 1. Instruments purchased on or before May 14, 2020 must be capable of being calibrated in the field with respect to the FEV 1 and FVC. This calibration of the FEV 1 and FVC may be either directly or indirectly through volume and time base measurements. The volume calibration source should provide a volume displacement of at least 2 liters and should be accurate to within + or−30 milliliters.
2. Instruments purchased after May 14, 2020 must be capable of having its calibration checked in the field and be recalibrated, if necessary, if the spirometer requires the technician to do so. The volume-calibration syringe shall provide a volume displacement of at least 3 liters and shall be accurate to within ± 0.5 percent of 3 liters (15 milliliters).
II. Technique for Measurement of Forced Vital Capacity Maneuver
a. Use of a nose clip is recommended but not required. The procedures shall be explained in simple terms to the worker who shall be instructed to loosen any tight clothing and stand in front of the apparatus. The worker may sit, but care should be taken on repeat testing that the same position be used and, if possible, the same spirometer. Particular attention shall be given to ensure that the chin is slightly elevated with the neck slightly extended. The worker shall be instructed to make a full inspiration from a normal breathing pattern and then blow into the apparatus, without interruption, as hard, fast, and completely as possible. At least three and no more than eight forced expirations shall be carried out. During the maneuvers, the worker shall be observed for compliance with instruction. The expirations shall be checked visually for technical acceptability and repeatability from flow-volume or volume-time tracings or displays. The following efforts shall be judged technically unacceptable when the worker:
1. Has not reached full inspiration preceding the forced expiration,
2. Has not used maximal effort during the entire forced expiration,
3. Has not tried to exhale continuously for at least 6 seconds and the volume-time curve shows no change in volume (<0.025 L) for at least one second,
4. Has coughed in the first second or closed the glottis,
5. Has an obstructed mouthpiece or a leak around the mouthpiece (obstruction due to tongue being placed in front of mouthpiece, false teeth falling in front of mouthpiece, etc.),
6. Has an unsatisfactory start of expiration, one characterized by excessive hesitation (or false starts), and, therefore, not allowing back extrapolation of time 0 (extrapolated volume on the volume-time tracing must be less than 150 milliliters or 5 percent of the FVC, whichever is greater.), and
7. Has an excessive variability between the acceptable curves. The difference between the two largest FVCs from the satisfactory tracings shall not exceed 150 milliliters and the difference between the two largest FEV 1 s of the satisfactory tracings shall not exceed 150 milliliters.
b. Calibration checks of the volume accuracy of the instrument for recording FVC and FEV 1 shall be performed daily or more frequently if specified by the spirometer manufacturer, using a 3-liter syringe. Calibration checks to ensure that the spirometer is recording 3 liters of injected air to within ±3.5 percent, or 2.90 to 3.10 liters, shall be conducted. Calibration checks of flow-type spirometers shall include injection of 3 liters air over a range of speeds, with injection times of 0.5 second, 3 seconds, and 6 or more seconds. Checks of volume-type spirometers shall include a single calibration check and a check to verify that the spirometer is not leaking more than 30 milliliters/minute air.
III. Interpretation of Spirogram
a. The first step in evaluating a spirogram should be to determine whether or not the worker has performed the test properly or as described in section II of this appendix. From the three satisfactory tracings, the forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV 1 ) shall be measured and recorded. The largest observed FVC and largest observed FEV 1 shall be used in the analysis regardless of the curve(s) on which they occur.
b. [Reserved]
IV. Qualifications of Personnel Administering the Test
Technicians who perform pulmonary function testing should have the basic knowledge required to produce meaningful results. Training consisting of approximately 16 hours of formal instruction should cover the following areas.
a. Basic physiology of the forced vital-capacity maneuver and the determinants of airflow limitation, with emphasis on the relation to repeatability of results.
b. Instrumentation requirements, including calibration check procedures, sources of error, and their correction.
c. Performance of the testing including worker coaching, recognition of improperly performed maneuvers and corrective actions.
d. Data quality with emphasis on repeatability.
e. Actual use of the equipment under supervised conditions.
f. Measurement of tracings and calculations of results.
[43 FR 27394, June 23, 1978; 43 FR 35035, Aug. 8, 1978, as amended at 45 FR 67340, Oct. 10, 1980; 50 FR 51173, Dec. 13, 1985; 51 FR 24325, July 3, 1986; 54 FR 24334, June 7, 1989; 61 FR 5508, Feb. 13, 1996; 63 FR 1290, Jan. 8, 1998; 65 FR 76567, Dec. 7, 2000; 70 FR 1142, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR 75586, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR 17782, Mar. 26, 2012; 84 FR 21490, May 14, 2019]
Authorized person means any person required by his duties to be present in regulated areas and authorized to do so by his employer, by this section, or by the Act. Authorized person also includes any person entering such areas as a designated representative of employees exercising an opportunity to observe employee exposure monitoring.
DBCP means 1,2-dibromo-3-chloropropane, Chemical Abstracts Service Registry Number 96-12-8, and includes all forms of DBCP.
Director means the Director, National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to equipment failure, rupture of containers, or failure of control equipment which may, or does, result in an unexpected release of DBCP.
OSHA Area Office means the Area Office of the Occupational Safety and Health Administration having jurisdiction over the geographic area where the affected workplace is located.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
The employer shall assure that no employee is exposed to an airborne concentration of DBCP in excess of 1 part DBCP per billion parts of air (ppb) as an 8-hour time-weighted average.
The employer shall assure that no employee is exposed to eye or skin contact with DBCP.
Each employer who has a place of employment in which DBCP is present, shall monitor each workplace and work operation to accurately determine the airborne concentrations of DBCP to which employees may be exposed.
Whenever there has been a production, process, control, or personnel change which may result in any new or additional exposure to DBCP, or whenever the employer has any reason to suspect new or additional exposures to DBCP, the employer shall monitor the employees potentially affected by such change for the purpose of redetermining their exposure.
The employer shall use a method of measurement which has an accuracy, to a confidence level of 95 percent, of not less than plus or minus 25 percent for concentrations of DBCP at or above the permissible exposure limit.
The employer shall institute engineering and work practice controls to reduce and maintain employee exposures to DBCP at or below the permissible exposure limit, except to the extent that the employer establishes that such controls are not feasible. Where feasible engineering and work practice controls are not sufficient to reduce employee exposures to within the permissible exposure limit, the employer shall nonetheless use them to reduce exposures to the lowest level achievable by these controls, and shall supplement them by use of respiratory protection.
For employees who are required to use respirators by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer must implement a respiratory protection program in accordance with § 1910.134(b) through (d) (except (d)(1)(iii)), and (f) through (m), which covers each employee required by this section to use a respirator.
Employers must:
Employees not engaged in correcting the emergency shall be removed and restricted from the area and normal operations in the affected area shall not be resumed until the emergency is abated.
Where there is a possibility of employee exposure to DBCP due to the occurrence of an emergency, a general alarm shall be installed and maintained to promptly alert employees of such occurrences.
For any employee exposed to DBCP in an emergency situation, the employer shall provide medical surveillance in accordance with paragraph (m)(6) of this section.
Where there is any possibility of eye or dermal contact with liquid or solid DBCP, the employer shall provide, at no cost to the employee, and assure that the employee wears impermeable protective clothing and equipment to protect the area of the body which may come in contact with DBCP. Eye and face protection shall meet the requirements of § 1910.133 of this part.
Where DBCP is present in a liquid form, or as a resultant vapor, all containers or vessels containing DBCP shall be enclosed to the maximum extent feasible and tightly covered when not in use.
DBCP waste scrap, debris, containers or equipment, shall be disposed of in sealed bags or other closed containers which prevent dispersion of DBCP outside the container.
The employer shall provide clean change rooms equipped with storage facilities for street clothes and separate storage facilities for protective clothing and equipment whenever employees are required to wear protective clothing and equipment in accordance with paragraphs (h) and (j) of this section.
The employer shall provide lunchroom facilities which have a temperature controlled, positive pressure, filtered air supply, and which are readily accessible to employees working in regulated areas.
The employer shall assure that, in regulated areas, food or beverages are not present or consumed, smoking products and implements are not present or used, and cosmetics are not present or applied.
At the time of initial assignment, and annually thereafter, the employer shall provide a medical examination for employees who work in regulated areas, which includes at least the following:
If the employee for any reason develops signs or symptoms commonly associated with exposure to DBCP, the employer shall provide the employee with a medical examination which shall include those elements considered appropriate by the examining physician.
The employer shall provide the following information to the examining physician:
If the employee is exposed to DBCP in an emergency situation, the employer shall provide the employee with a sperm count test as soon as practicable, or, if the employee has been vasectionized or is unable to produce a semen specimen, the hormone tests contained in paragraph (m)(2)(iii) of this section. The employer shall provide these same tests three months later.
DANGER
1,2-Dibromo-3-chloropropane
MAY CAUSE CANCER
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
1,2-Dibromo-3-chloropropane
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATOR REQUIRED
DANGER
1,2-Dibromo-3-chloropropane
CANCER HAZARD
The employer shall provide affected employees, or their designated representatives, with an opportunity to observe any monitoring of employee exposure to DBCP required by this section.
The information contained in the appendices is not intended, by itself, to create any additional obligations not otherwise imposed or to detract from any existing obligation.
Appendix A to § 1910.1044—Substance Safety Data Sheet For DBCP
i. Substance Identification
A. Synonyms and trades names: DBCP; Dibromochloropropane; Fumazone (Dow Chemical Company TM); Nemafume; Nemagon (Shell Chemical Co. TM); Nemaset; BBC 12; and OS 1879.
B. Permissible exposure:
1. Airborne. 1 part DBCP vapor per billion parts of air (1 ppb); time-weighted average (TWA) for an 8-hour workday.
2. Dermal. Eye contact and skin contact with DBCP are prohibited.
C. Appearance and odor: Technical grade DBCP is a dense yellow or amber liquid with a pungent odor. It may also appear in granular form, or blended in varying concentrations with other liquids.
D. Uses: DBCP is used to control nematodes, very small worm-like plant parasites, on crops including cotton, soybeans, fruits, nuts, vegetables and ornamentals.
ii. Health Hazard Data
A. Routes of entry: Employees may be exposed:
1. Through inhalation (breathing);
2. Through ingestion (swallowing);
3. Skin contact; and
4. Eye contact.
B. Effects of exposure:
1. Acute exposure. DBCP may cause drowsiness, irritation of the eyes, nose, throat and skin, nausea and vomiting. In addition, overexposure may cause damage to the lungs, liver or kidneys.
2. Chronic exposure. Prolonged or repeated exposure to DBCP has been shown to cause sterility in humans. It also has been shown to produce cancer and sterility in laboratory animals and has been determined to constitute an increased risk of cancer in man.
3. Reporting Signs and Symptoms. If you develop any of the above signs or symptoms that you think are caused by exposure to DBCP, you should inform your employer.
iii. Emergency First Aid Procedures
A. Eye exposure. If DBCP liquid or dust containing DBCP gets into your eyes, wash your eyes immediately with large amounts of water, lifting the lower and upper lids occasionally. Get medical attention immediately. Contact lenses should not be worn when working with DBCP.
B. Skin exposure. If DBCP liquids or dusts containing DBCP get on your skin, immediately wash using soap or mild detergent and water. If DBCP liquids or dusts containing DBCP penetrate through your clothing, remove the clothing immediately and wash. If irritation is present after washing get medical attention.
C. Breathing. If you or any person breathe in large amounts of DBCP, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Do not use mouth-to-mouth. Keep the affected person warm and at rest. Get medical attention as soon as possible.
D. Swallowing. When DBCP has been swallowed and the person is conscious, give the person large amounts of water immediately. After the water has been swallowed, try to get the person to vomit by having him touch the back of his throat with his finger. Do not make an unconscious person vomit. Get medical attention immediately.
E. Rescue. Notify someone. Put into effect the established emergency rescue procedures. Know the locations of the emergency rescue equipment before the need arises.
iv. Respirators and Protective Clothing
A. Respirators. You may be required to wear a respirator in emergencies and while your employer is in the process of reducing DBCP exposures through engineering controls. If respirators are worn, they must have a National Institute for Occupational Safety and Health (NIOSH) approval label (Older respirators may have a Bureau of Mines Approval label). For effective protection, a respirator must fit your face and head snugly. The respirator should not be loosened or removed in work situations where its use is required. DBCP does not have a detectable odor except at 1,000 times or more above the permissible exposure limit. If you can smell DBCP while wearing a respirator, the respirator is not working correctly; go immediately to fresh air. If you experience difficulty breathing while wearing a respirator, tell your employer.
B. Protective clothing. When working with DBCP you must wear for your protection impermeable work clothing provided by your employer. (Standard rubber and neoprene protective clothing do not offer adequate protection).
DBCP must never be allowed to remain on the skin. Clothing and shoes must not be allowed to become contaminated with DBCP, and if they do, they must be promptly removed and not worn again until completely free of DBCP. Turn in impermeable clothing that has developed leaks for repair or replacement.
C. Eye protection. You must wear splash-proof safety goggles where there is any possibility of DBCP liquid or dust contacting your eyes.
v. Precautions for Safe Use, Handling, and Storage
A. DBCP must be stored in tightly closed containers in a cool, well-ventilated area.
B. If your work clothing may have become contaminated with DBCP, or liquids or dusts containing DBCP, you must change into uncontaminated clothing before leaving the work premises.
C. You must promptly remove any protective clothing that becomes contaminated with DBCP. This clothing must not be reworn until the DBCP is removed from the clothing.
D. If your skin becomes contaminated with DBCP, you must immediately and thoroughly wash or shower with soap or mild detergent and water to remove any DBCP from your skin.
E. You must not keep food, beverages, cosmetics, or smoking materials, nor eat or smoke, in regulated areas.
F. If you work in a regulated area, you must wash your hands thoroughly with soap or mild detergent and water, before eating, smoking or using toilet facilities.
G. If you work in a regulated area, you must remove any protective equipment or clothing before leaving the regulated area.
H. Ask your supervisor where DBCP is used in your work area and for any additional safety and health rules.
vi. Access to Information
A. Each year, your employer is required to inform you of the information contained in this Substance Safety Data Sheet for DBCP. In addition, your employer must instruct you in the safe use of DBCP, emergency procedures, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being exposed to DBCP. You or your representative have the right to observe employee exposure measurements and to record the result obtained. Your employer is required to inform you of your exposure. If your employer determines that you are being overexposed, he is required to inform you of the actions which are being taken to reduce your exposure.
C. Your employer is required to keep records of your exposure and medical examinations. Your employer is required to keep exposure and medical data for at least 40 years or the duration of your employment plus 20 years, whichever is longer.
D. Your employer is required to release exposure and medical records to you, your physician, or other individual designated by you upon your written request.
Appendix B to § 1910.1044—Substance Technical Guidelines for DBCP
i. Physical and Chemical Data
A. Substance Identification
1. Synonyms: 1,2-dibromo-3-chloropropane; DBCP, Fumazone; Nemafume; Nemagon; Nemaset; BBC 12; OS 1879. DBCP is also included in agricultural pesticides and fumigants which include the phrase “Nema—” in their name.
2. Formula: C3H5Br2 C1.
3. Molecular Weight: 236.
B. Physical Data:
1. Boiling point (760 mm HG): 195C (383F)
2. Specific gravity (water = 1): 2.093.
3. Vapor density (air = 1 at boiling point of DBCP): Data not available.
4. Melting point: 6C (43F).
5. Vapor pressure at 20C (68F): 0.8 mm Hg
6. Solubility in water: 1000 ppm.
7. Evaporation rate (Butyl Acetate = 1): very much less than 1.
8. Appearance and odor: Dense yellow or amber liquid with a pungent odor at high concentrations. Any detectable odor of DBCP indicates overexposure.
ii. Fire Explosion and Reactivity Hazard Data
A. Fire
1. Flash point: 170F (77C)
2. Autoignition temperature: Data not available.
3. Flammable limits in air, percent by volume: Data not available.
4. Extinguishing media: Carbon dioxide, dry chemical.
5. Special fire-fighting procedures: Do not use a solid stream of water since a stream will scatter and spread the fire. Use water spray to cool containers exposed to a fire.
6. Unusual fire and explosion hazards: None known.
7. For purposes of complying with the requirements of § 1910.106, liquid DBCP is classified as a Category 4 flammable liquid.
8. For the purpose of complying with § 1910.309, the classification of hazardous locations as described in article 500 of the National Electrical Code for DBCP shall be Class I, Group D.
9. For the purpose of compliance with § 1910.157, DBCP is classified as a Class B fire hazard.
10. For the purpose of compliance with § 1910.178, locations classified as hazardous locations due to the presence of DBCP shall be Class I, Group D.
11. Sources of ignition are prohibited where DBCP presents a fire or explosion hazard.
B. Reactivity
1. Conditions contributing to instability: None known.
2. Incompatibilities: Reacts with chemically active metals, such as aluminum, magnesium and tin alloys.
3. Hazardous decomposition products: Toxic gases and vapors (such as HBr, HCl and carbon monoxide) may be released in a fire involving DBCP.
4. Special precautions: DBCP will attack some rubber materials and coatings.
iii. Spill, Leak and Disposal Procedures
A. If DBCP is spilled or leaked, the following steps should be taken:
1. The area should be evacuated at once and re-entered only after thorough ventilation.
2. Ventilate area of spill or leak.
3. If in liquid form, collect for reclamation or absorb in paper, vermiculite, dry sand, earth or similar material.
4. If in solid form, collect spilled material in the most convenient and safe manner for reclamation or for disposal.
B. Persons not wearing protective equipment must be restricted from areas of spills or leaks until cleanup has been completed.
C. Waste Disposal Methods:
1. For small quantities of liquid DBCP, absorb on paper towels, remove to a safe place (such as a fume hood) and burn the paper. Large quantities can be reclaimed or collected and atomized in a suitable combustion chamber equipped with an appropriate effluent gas cleaning device. If liquid DBCP is absorbed in vermiculite, dry sand, earth or similar material and placed in sealed containers it may be disposed of in a State-approved sanitary landfill.
2. If in solid form, for small quantities, place on paper towels, remove to a safe place (such as a fume hood) and burn. Large quantities may be reclaimed. However, if this is not practical, dissolve in a flammable solvent (such as alcohol) and atomize in a suitable combustion chamber equipped with an appropriate effluent gas cleaning device. DBCP in solid form may also be disposed in a state-approved sanitary landfill.
iv. Monitoring and Measurement Procedures
A. Exposure above the permissible exposure limit.
1. Eight Hour Exposure Evaluation: Measurements taken for the purpose of determining employee exposure under this section are best taken so that the average 8-hour exposure may be determined from a single 8-hour sample or two (2) 4-hour samples. Air samples should be taken in the employee's breathing zone (air that would most nearly represent that inhaled by the employee).
2. Monitoring Techniques: The sampling and analysis under this section may be performed by collecting the DBCP vapor on petroleum based charcoal absorption tubes with subsequent chemical analyses. The method of measurement chosen should determine the concentration of airborne DBCP at the permissible exposure limit to an accuracy of plus or minus 25 percent. If charcoal tubes are used, a total volume of 10 liters should be collected at a flow rate of 50 cc. per minute for each tube. Analyze the resultant samples as you would samples of halogenated solvent.
B. Since many of the duties relating to employee protection are dependent on the results of monitoring and measuring procedures, employers should assure that the evaluation of employee exposures is performed by a competent industrial hygienist or other technically qualified person.
v. Protective Clothing
Employees should be required to wear appropriate protective clothing to prevent any possibility of skin contact with DBCP. Because DBCP is absorbed through the skin, it is important to prevent skin contact with both liquid and solid forms of DBCP. Protective clothing should include impermeable coveralls or similar fullbody work clothing, gloves, headcoverings, and workshoes or shoe coverings. Standard rubber and neoprene gloves do not offer adequate protection and should not be relied upon to keep DBCP off the skin. DBCP should never be allowed to remain on the skin. Clothing and shoes should not be allowed to become contaminated with the material, and if they do, they should be promptly removed and not worn again until completely free of the material. Any protective clothing which has developed leaks or is otherwise found to be defective should be repaired or replaced. Employees should also be required to wear splash-proof safety goggles where there is any possibility of DBCP contacting the eyes.
vi. Housekeeping and Hygiene Facilities
1. The workplace must be kept clean, orderly and in a sanitary condition;
2. Dry sweeping and the use of compressed air is unsafe for the cleaning of floors and other surfaces where DBCP dust or liquids are found. To minimize the contamination of air with dust, vacuuming with either portable or permanent systems must be used. If a portable unit is selected, the exhaust must be attached to the general workplace exhaust ventilation system, or collected within the vacuum unit equipped with high efficiency filters or other appropriate means of contamination removal and not used for other purposes. Units used to collect DBCP must be labeled.
3. Adequate washing facilities with hot and cold water must be provided, and maintained in a sanitary condition. Suitable cleansing agents should also be provided to assure the effective removal of DBCP from the skin.
4. Change or dressing rooms with individual clothes storage facilities must be provided to prevent the contamination of street clothes with DBCP. Because of the hazardous nature of DBCP, contaminated protective clothing must be stored in closed containers for cleaning or disposal.
vii. Miscellaneous Precautions
A. Store DBCP in tightly closed containers in a cool, well ventilated area.
B. Use of supplied-air suits or other impervious clothing (such as acid suits) may be necessary to prevent skin contact with DBCP. Supplied-air suits should be selected, used, and maintained under the supervision of persons knowlegeable in the limitations and potential life-endangering characteristics of supplied-air suits.
C. The use of air-conditioned suits may be necessary in warmer climates.
D. Advise employees of all areas and operations where exposure to DBCP could occur.
viii. Common Operations
Common operations in which exposure to DBCP is likely to occur are: during its production; and during its formulation into pesticides and fumigants.
Appendix C to § 1910.1044—Medical Surveillance Guidelines For DBCP
i. Route of Entry
Inhalation; skin absorption
ii. Toxicology
Recent data collected on workers involved in the manufacture and formulation of DBCP has shown that DBCP can cause sterility at very low levels of exposure. This finding is supported by studies showing that DBCP causes sterility in animals. Chronic exposure to DBCP resulted in pronounced necrotic action on the parenchymatous organs ( i.e., liver, kidney, spleen) and on the testicles of rats at concentrations as low as 5 ppm. Rats that were chronically exposed to DBCP also showed changes in the composition of the blood, showing low RBC, hemoglobin, and WBC, and high reticulocyte levels as well as functional hepatic disturbance, manifesting itself in a long prothrombin time. Reznik et al. noted a single dose of 100 mg produced profound depression of the nervous system of rats. Their condition gradually improved. Acute exposure also resulted in the destruction of the sex gland activity of male rats as well as causing changes in the estrous cycle in female rats. Animal studies have also associated DBCP with an increased incidence of carcinoma. Olson, et al. orally administered DBCP to rats and mice 5 times per week at experimentally predetermined maximally tolerated doses and at half those doses. As early as ten weeks after initiation of treatment, DBCP induced a high incidence of squamous cell carcinomas of the stomach with metastases in both species. DBCP also induced mammary adenocarcinomas in the female rats at both dose levels.
iii. Signs and Symptoms
A. Inhalation: Nausea, eye irritation, conjunctivitis, respiratory irritation, pulmonary congestion or edema, CNS depression with apathy, sluggishness, and ataxia.
B. Dermal: Erythema or inflammation and dermatitis on repeated exposure.
iv. Special Tests
A. Semen analysis: The following information excerpted from the document “Evaluation of Testicular Function”, submitted by the Corporate Medical Department of the Shell Oil Company (exhibit 39-3), may be useful to physicians conducting the medical surveillance program;
In performing semen analyses certain minimal but specific criteria should be met:
1. It is recommended that a minimum of three valid semen analyses be obtained in order to make a determination of an individual's average sperm count.
2. A period of sexual abstinence is necessary prior to the collection of each masturbatory sample. It is recommended that intercourse or masturbation be performed 48 hours before the actual specimen collection. A period of 48 hours of abstinence would follow; then the masturbatory sample would be collected.
3. Each semen specimen should be collected in a clean, widemouthed, glass jar (not necessarily pre-sterilized) in a manner designated by the examining physician. Any part of the seminal fluid exam should be initialed only after liquifaction is complete, i.e., 30 to 45 minutes after collection.
4. Semen volume should be measured to the nearest 1/10 of a cubic centimeter.
5. Sperm density should be determined using routine techniques involving the use of a white cell pipette and a hemocytometer chamber. The immobilizing fluid most effective and most easily obtained for this process is distilled water.
6. Thin, dry smears of the semen should be made for a morphologic classification of the sperm forms and should be stained with either hematoxalin or the more difficult, yet more precise, Papanicolaou technique. Also of importance to record is obvious sperm agglutination, pyospermia, delayed liquifaction (greater than 30 minutes), and hyperviscosity. In addition, pH, using nitrazine paper, should be determined.
7. A total morphology evaluation should include percentages of the following:
a. Normal (oval) forms,
b. Tapered forms,
c. Amorphous forms (include large and small sperm shapes),
d. Duplicated (either heads or tails) forms, and
e. Immature forms.
8. Each sample should be evaluated for sperm viability (percent viable sperm moving at the time of examination) as well as sperm motility (subjective characterization of “purposeful forward sperm progression” of the majority of those viable sperm analyzed) within two hours after collection, ideally by the same or equally qualified examiner.
B. Serum determinations: The following serum determinations should be performed by radioimmuno-assay techniques using National Institutes of Health (NIH) specific antigen or antigen preparations of equivalent sensitivity:
1. Serum follicle stimulating hormone (FSH);
2. Serum luteinizing hormone (LH); and
3. Serum total estrogen (females only).
v. Treatment
Remove from exposure immediately, give oxygen or artificial resuscitation if indicated. Contaminated clothing and shoes should be removed immediately. Flush eyes and wash contaminated skin. If swallowed and the person is conscious, induce vomiting. Recovery from mild exposures is usually rapid and complete.
vi. Surveillance and Preventive Considerations
A. Other considerations. DBCP can cause both acute and chronic effects. It is important that the physician become familiar with the operating conditions in which exposure to DBCP occurs. Those with respiratory disorders may not tolerate the wearing of negative pressure respirators.
B. Surveillance and screening. Medical histories and laboratory examinations are required for each employee subject to exposure to DBCP. The employer should screen employees for history of certain medical conditions (listed below) which might place the employee at increased risk from exposure.
1. Liver disease. The primary site of biotransformation and detoxification of DBCP is the liver. Liver dysfunctions likely to inhibit the conjugation reactions will tend to promote the toxic actions of DBCP. These precautions should be considered before exposing persons with impaired liver function to DBCP.
2. Renal disease. Because DBCP has been associated with injury to the kidney it is important that special consideration be given to those with possible impairment of renal function.
3. Skin desease. DBCP can penetrate the skin and can cause erythema on prolonged exposure. Persons with pre-existing skin disorders may be more susceptible to the effects of DBCP.
4. Blood dyscrasias. DBCP has been shown to decrease the content of erythrocytes, hemoglobin, and leukocytes in the blood, as well as increase the prothrombin time. Persons with existing blood disorders may be more susceptible to the effects of DBCP.
5. Reproductive disorders. Animal studies have associated DBCP with various effects on the reproductive organs. Among these effects are atrophy of the testicles and changes in the estrous cycle. Persons with pre-existing reproductive disorders may be at increased risk to these effects of DBCP.
References
1. Reznik, Ya. B. and Sprinchan, G. K.: Experimental Data on the Gonadotoxic effect of Nemagon, Gig. Sanit., (6), 1975, pp. 101-102, (translated from Russian).
2. Faydysh, E. V., Rakhmatullaev, N. N. and Varshavskii, V. A.: The Cytotoxic Action of Nemagon in a Subacute Experiment, Med. Zh. Uzbekistana, (No. 1), 1970, pp. 64-65, (translated from Russian).
3. Rakhmatullaev, N. N.: Hygienic Characteristics of the Nematocide Nemagon in Relation to Water Pollution Control, Hyg. Sanit., 36(3), 1971, pp. 344-348, (translated from Russian).
4. Olson, W. A. et al.: Induction of Stomach Cancer in Rats and Mice by Halogenated Aliphatic Fumigants, Journal of the National Cancer Institute, (51), 1973, pp. 1993-1995.
5. Torkelson, T. R. et al.: Toxicologic Investigations of 1,2-Dibromo-3-chloropropane, Toxicology and Applied Pharmacology, 3, 1961 pp. 545-559.
[43 FR 11527, Mar. 17, 1978, as amended at 45 FR 35283, May 23, 1980; 49 FR 18295, Apr. 30, 1984; 54 FR 24334, June 7, 1989; 58 FR 35310, June 30, 1993; 61 FR 5508, Feb. 13, 1996; 63 FR 1291, Jan. 8, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16772, Apr. 3, 2006; 71 FR 50189, Aug. 24, 2006; 73 FR 75586, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR 17782, Mar. 26, 2012; 78 FR 9313, Feb. 8, 2013]
resins, SAN resins, nitrile barrier resins, solid nitrile elastomers, and acrylic and modacrylic fibers, when these listed materials are in the form of finished polymers, and products fabricated from such finished polymers;
Acrylonitrile or AN means acrylonitrile monomer, chemical formula CH 2 = CHCN.
Action level means a concentration of AN of 1 ppm as an eight (8)-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer whose duties require the person to enter a regulated area, or any person entering such an area as a designated representative of employees for the purpose of exercising the opportunity to observe monitoring procedures under paragraph (r) of this section.
Decontamination means treatment of materials and surfaces by water washdown, ventilation, or other means, to assure that the materials will not expose employees to airborne concentrations of AN above 1 means the Director, National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment, which results in an unexpected massive release of AN.
Liquid AN means AN monomer in liquid form, and liquid or semiliquid polymer intermediates, including slurries, suspensions, emulsions, and solutions, produced during the polymerization of AN.
OSHA Area Office means the Area Office of the Occupational Safety and Health Administration having jurisdiction over the geographic area where the affected workplace is located.
The employer shall assure that no employee is exposed to an airborne concentration of acrylonitrile in excess of two (2) parts acrylonitrile per million parts of air (2 ppm) as an eight (8)-hour time-weighted average.
The employer shall assure that no employee is exposed to an airborne concentration of acrylonitrile in excess of ten (10) ppm as averaged over any fifteen (15)-minute period during the work day.
The employer shall assure that no employee is exposed to skin contact or eye contact with liquid AN.
Each employer who has a place of employment in which AN is present shall monitor each such workplace and work operation to accurately determine the airborne concentrations of AN to which employees may be exposed.
Whenever there has been a production, process, control, or personnel change which may result in new or additional exposures to AN, or whenever the employer has any other reason to suspect a change which may result in new or additional exposures to AN, additional monitoring which complies with this paragraph shall be conducted.
The method of measurement of employee exposures shall be accurate to a confidence level of 95 percent, to within plus or minus 35 percent for concentrations of AN at or above the permissible exposure limits, and plus or minus 50 percent for concentrations of AN below the permissible exposure limits.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Employers must:
Where there is the possibility of employee exposure to AN in excess of the ceiling limit, a general alarm shall be installed and used to promptly alert employees of such occurrences.
Where eye or skin contact with liquid AN may occur, the employer shall provide at no cost to the employee, and assure that employees wear, impermeable protective clothing or other equipment to protect any area of the body which may come in contact with liquid AN. The provision of §§ 1910.132 and 1910.133 shall be complied with.
AN waste, scrap, debris, bags, containers, or equipment shall be decontaminated before being incorporated in the general waste disposal system.
At the time of initial assignment, or upon institution of the medical surveillance program, the employer shall provide each affected employee an opportunity for a medical examination, including at least the following elements:
by 17-inch or other reasonably-sized standard film or digital posterior-anterior chest X-ray; and
If the employee for any reason develops signs or symptoms which may be associated with exposure to AN, the employer shall provide an appropriate examination and emergency medical treatment.
The employer shall provide the following information to the examining physician:
DANGER
ACRYLONITRILE (AN)
MAY CAUSE CANCER
RESPIRATORY PROTECTION MAY BE REQURED IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
ACRYLONITRILE (AN)
CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORS MAY BE REQUIRED
DANGER
CONTAINS ACRYLONITRILE (AN)
CANCER HAZARD
The employer shall provide affected employees, or their designated representatives, an opportunity to observe any monitoring of employee exposure to AN conducted pursuant to paragraph (e) of this section.
The information contained in the appendixes is not intended, by itself, to create any additional obligation not otherwise imposed, or to detract from any obligation.
Appendix A to § 1910.1045—Substance Safety Data Sheet for Acrylonitrile
i. Substance Identification
A. Substance: Acrylonitrile (CH 2 CHCN).
B. Synonyms: Propenenitrile; vinyl cyanide; cyanoethylene; AN; VCN; acylon; carbacryl; fumigrian; ventox.
C. Acrylonitrile can be found as a liquid or vapor, and can also be found in polymer resins, rubbers, plastics, polyols, and other polymers having acrylonitrile as a raw or intermediate material.
D. AN is used in the manufacture of acrylic and modiacrylic fibers, acrylic plastics and resins, speciality polymers, nitrile rubbers, and other organic chemicals. It has also been used as a fumigant.
E. Appearance and odor: Colorless to pale yellow liquid with a pungent odor which can only be detected at concentrations above the permissible exposure level, in a range of 13-19 parts AN per million parts of air (13-19 ppm).
F. Permissible exposure: Exposure may not exceed either:
1. Two parts AN per million parts of air (2 ppm) averaged over the 8-hour workday; or
2. Ten parts AN per million parts of air (10 ppm) averaged over any 15-minute period in the workday.
3. In addition, skin and eye contact with liquid AN is prohibited.
ii. Health Hazard Data
A. Acrylonitrile can affect your body if you inhale the vapor (breathing), if it comes in contact with your eyes or skin, or if you swallow it. It may enter your body through your skin.
B. Effects of overexposure: 1. Short-term exposure: Acrylonitrile can cause eye irritation, nausea, vomiting, headache, sneezing, weakness, and light-headedness. At high concentrations, the effects of exposure may go on to loss of consciousness and death. When acrylonitrile is held in contact with the skin after being absorbed into shoe leather or clothing, it may produce blisters following several hours of no apparent effect. Unless the shoes or clothing are removed immediately and the area washed, blistering will occur. Usually there is no pain or inflammation associated with blister formation.
2. Long-term exposure: Acrylonitrile has been shown to cause cancer in laboratory animals and has been associated with higher incidences of cancer in humans. Repeated or prolonged exposure of the skin to acrylonitrile may produce irritation and dermatitis.
3. Reporting signs and symptoms: You should inform your employer if you develop any signs or symptoms and suspect they are caused by exposure to acrylonitrile.
iii. Emergency First Aid Procedures
A. Eye exposure: If acrylonitrile gets into your eyes, wash your eyes immediately with large amounts of water, lifting the lower and upper lids occasionally. Get medical attention immediately. Contact lenses should not be worn when working with this chemical.
B. Skin exposure: If acrylonitrile gets on your skin, immediately wash the contaminated skin with water. If acrylonitrile soaks through your clothing, especially your shoes, remove the clothing immediately and wash the skin with water. If symptoms occur after washing, get medical attention immediately. Thoroughly wash the clothing before reusing. Contaminated leather shoes or other leather articles should be discarded.
C. Inhalation: If you or any other person breathes in large amounts of acrylonitrile, move the exposed person to fresh air at once. If breathing has stopped, perform artificial respiration. Keep the affected person warm and at rest. Get medical attention as soon as possible.
D. Swallowing: When acrylonitrile has been swallowed, give the person large quantities of water immediately. After the water has been swallowed, try to get the person to vomit by having him touch the back of his throat with his finger. Do not make an unconscious person vomit. Get medical attention immediately.
E. Rescue: Move the affected person from the hazardous exposure. If the exposed person has been overcome, notify someone else and put into effect the established emergency procedures. Do not become a casualty yourself. Understand your emergency rescue procedures and know the location of the emergency equipment before the need arises.
F. Special first aid procedures: First aid kits containing an adequate supply (at least two dozen) of amyl nitrite pearls, each containing 0.3 ml, should be maintained at each site where acrylonitrile is used. When a person is suspected of receiving an overexposure to acrylonitrile, immediately remove that person from the contaminated area using established rescue procedures. Contaminated clothing must be removed and the acrylonitrile washed from the skin immediately. Artificial respiration should be started at once if breathing has stopped. If the person is unconscious, amyl nitrite may be used as an antidote by a properly trained individual in accordance with established emergency procedures. Medical aid should be obtained immediately.
iv. Respirators and Protective Clothing
A. Respirators. You may be required to wear a respirator for nonroutine activities, in emergencies, while your employer is in the process of reducing acrylonitrile exposures through engineering controls, and in areas where engineering controls are not feasible. If respirators are worn, they must have a label issued by the National Institute for Occupational Safety and Health under the provisions of 42 CFR part 84 stating that the respirators have been approved for use with organic vapors. For effective protection, respirators must fit your face and head snugly. Respirators must not be loosened or removed in work situations where their use is required.
Acrylonitrile does not have a detectable odor except at levels above the permissible exposure limits. Do not depend on odor to warn you when a respirator cartridge or canister is exhausted. Cartridges or canisters must be changed daily or before the end-of-service-life, whichever comes first. Reuse of these may allow acrylonitrille to gradually filter through the cartridge and cause exposures which you cannot detect by odor. If you can smell acrylonitrile while wearing a respirator, proceed immediately to fresh air. If you experience difficulty breathing while wearing a respirator, tell your employer.
B. Supplied-air suits: In some work situations, the wearing of supplied-air suits may be necessary. Your employer must instruct you in their proper use and operation.
C. Protective clothing: You must wear impervious clothing, gloves, face shield, or other appropriate protective clothing to prevent skin contact with liquid acrylonitrile. Where protective clothing is required, your employer is required to provide clean garments to you as necessary to assume that the clothing protects you adequately.
Replace or repair impervious clothing that has developed leaks.
Acrylonitrile should never be allowed to remain on the skin. Clothing and shoes which are not impervious to acrylonitrile should not be allowed to become contaminated with acrylonitrile, and if they do the clothing and shoes should be promptly removed and decontaminated. The clothing should be laundered or discarded after the AN is removed. Once acrylonitrile penetrates shoes or other leather articles, they should not be worn again.
D. Eye protection: You must wear splashproof safety goggles in areas where liquid acrylonitrile may contact your eyes. In addition, contact lenses should not be worn in areas where eye contact with acrylonitrile can occur.
v. Precautions for Safe Use, Handling, and Storage
A. Acrylonitrile is a flammable liquid, and its vapors can easily form explosive mixtures in air.
B. Acrylonitrile must be stored in tightly closed containers in a cool, well-ventilated area, away from heat, sparks, flames, strong oxidizers (especially bromine), strong bases, copper, copper alloys, ammonia, and amines.
C. Sources of ignition such as smoking and open flames are prohibited wherever acrylonitrile is handled, used, or stored in a manner that could create a potential fire or explosion hazard.
D. You should use non-sparking tools when opening or closing metal containers of acrylonitrile, and containers must be bonded and grounded when pouring or transferring liquid acrylonitrile.
E. You must immediately remove any non-impervious clothing that becomes wetted with acrylonitrile, and this clothing must not be reworn until the acrylonitrile is removed from the clothing.
F. Impervious clothing wet with liquid acrylonitrile can be easily ignited. This clothing must be washed down with water before you remove it.
G. If your skin becomes wet with liquid acrylonitrile, you must promptly and thoroughly wash or shower with soap or mild detergent to remove any acrylonitrile from your skin.
H. You must not keep food, beverages, or smoking materials, nor are you permitted to eat or smoke in regulated areas where acrylonitrile concentrations are above the permissible exposure limits.
I. If you contact liquid acrylonitrile, you must wash your hands thoroughly with soap or mild detergent and water before eating, smoking, or using toilet facilities.
J. Fire extinguishers and quick drenching facilities must be readily available, and you should know where they are and how to operate them.
K. Ask your supervisor where acrylonitrile is used in your work area and for any additional plant safety and health rules.
vi. Access to Information
A. Each year, your employer is required to inform you of the information contained in this Substance Safety Data Sheet for acrylonitrile. In addition, you employer must instruct you in the proper work practices for using acrylonitrile, emergency procedures, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being exposed to acrylonitrile. You or your representative has the right to observe employee measurements and to record the results obtained. Your employer is required to inform you of your exposure. If your employer determines that you are being overexposed, he or she is required to inform you of the actions which are being taken to reduce your exposure to within permissible exposure limits.
C. Your employer is required to keep records of your exposures and medical examinations. These records must be kept by the employer for at least forty (40) years or for the period of your employment plus twenty (20) years, whichever is longer.
D. Your employer is required to release your exposure and medical records to you or your representative upon your request.
Appendix B to § 1910.1045—Substance Technical Guidelines for Acrylonitrile
i. Physical and Chemical Data
A. Substance identification: 1. Synonyms: AN; VCN; vinyl cyanide; propenenitrile; cyanoethylene; Acrylon; Carbacryl; Fumigrain; Ventox.
2. Formula: CH2 = CHCN.
3. Molecular weight: 53.1.
B. Physical data: 1. Boiling point (760 mm Hg): 77.3 °C (171 °F);
2. Specific gravity (water = 1): 0.81 (at 20 °C or 68 °F);
3. Vapor density (air = 1 at boiling point of acrylonitrile): 1.83;
4. Melting point: −83 °C (−117 °F);
5. Vapor pressure (@20 °F): 83 mm Hg;
6. Solubility in water, percent by weight @20 °C (68 °F): 7.35;
7. Evaporation rate (Butyl Acetate = 1): 4.54; and
8. Appearance and odor: Colorless to pale yellow liquid with a pungent odor at concentrations above the permissible exposure level. Any detectable odor of acrylonitrile may indicate overexposure.
ii. Fire, Explosion, and Reactivity Hazard Data
A. Fire: 1. Flash point: −1 °C (30 °F) (closed cup).
2. Autoignition temperature: 481 °C (898 °F).
3. Flammable limits air, percent by volume: Lower: 3, Upper: 17.
4. Extinguishing media: Alcohol foam, carbon dioxide, and dry chemical.
5. Special fire-fighting procedures: Do not use a solid stream of water, since the stream will scatter and spread the fire. Use water to cool containers exposed to a fire.
6. Unusual fire and explosion hazards: Acrylonitrile is a flammable liquid. Its vapors can easily form explosive mixtures with air. All ignition sources must be controlled where acrylonitrile is handled, used, or stored in a manner that could create a potential fire or explosion hazard. Acrylonitrile vapors are heavier than air and may travel along the ground and be ignited by open flames or sparks at locations remote from the site at which acrylonitrile is being handled.
7. For purposes of compliance with the requirements of 29 CFR 1910.106, acrylonitrile is classified as a class IB flammable liquid. For example, 7,500 ppm, approximately one-fourth of the lower flammable limit, would be considered to pose a potential fire and explosion hazard.
8. For purposes of compliance with 29 CFR 1910.157, acrylonitrile is classified as a Class B fire hazard.
9. For purpose of compliance with 29 CFR 1919.309, locations classified as hazardous due to the presence of acrylonitrile shall be Class I, Group D.
B. Reactivity:
1. Conditions contributing to instability: Acrylonitrile will polymerize when hot, and the additional heat liberated by the polymerization may cause containers to explode. Pure AN may self-polymerize, with a rapid build-up of pressure, resulting in an explosion hazard. Inhibitors are added to the commercial product to prevent self-polymerization.
2. Incompatibilities: Contact with strong oxidizers (especially bromine) and strong bases may cause fires and explosions. Contact with copper, copper alloys, ammonia, and amines may start serious decomposition.
3. Hazardous decompostion products: Toxic gases and vapors (such as hydrogen cyanide, oxides of nitrogen, and carbon monoxide) may be released in a fire involving acrylonitrile and certain polymers made from acrylonitrile.
4. Special precautions: Liquid acrylonitrile will attack some forms of plastics, rubbers, and coatings.
iii. Spill, Leak, and Disposal Procedures
A. If acrylonitrile is spilled or leaked, the following steps should be taken:
1. Remove all ignition sources.
2. The area should be evacuated at once and re-entered only after the area has been thoroughly ventilated and washed down with water.
3. If liquid acrylonitrile or polymer intermediate, collect for reclamation or absorb in paper, vermiculite, dry sand, earth, or similar material, or wash down with water into process sewer system.
B. Persons not wearing protective equipment should be restricted from areas of spills or leaks until clean-up has been completed.
C. Waste disposal methods: Waste material shall be disposed of in a manner that is not hazardous to employees or to the general population. Spills of acrylonitrile and flushing of such spills shall be channeled for appropriate treatment or collection for disposal. They shall not be channeled directly into the sanitary sewer system. In selecting the method of waste disposal, applicable local, State, and Federal regulations should be consulted.
iv. Monitoring and Measurement Procedures
A. Exposure above the Permissible Exposure Limit:
1. Eight-hour exposure evaluation: Measurements taken for the purpose of determining employee exposure under this section are best taken so that the average 8-hour exposure may be determined from a single 8-hour sample or two (2) 4-hour samples. Air samples should be taken in the employee's breathing zone (air that would most nearly represent that inhaled by the employee.)
2. Ceiling evaluation: Measurements taken for the purpose of determining employee exposure under this section must be taken during periods of maximum expected airborne concentrations of acrylonitrile in the employee's breathing zone. A minimum of three (3) measurements should be taken on one work shift. The average of all measurements taken is an estimate of the employee's ceiling exposure.
3. Monitoring techniques: The sampling and analysis under this section may be performed by collecting the acrylonitrile vapor on charcoal adsorption tubes or other composition adsorption tubes, with subsequent chemical analysis. Sampling and analysis may also be performed by instruments such as real-time continuous monitoring systems, portable direct-reading instruments, or passive dosimeters. Analysis of resultant samples should be by gas chromatograph.
Appendix D lists methods of sampling and analysis which have been tested by NIOSH and OSHA for use with acrylonitrile. NIOSH and OSHA have validated modifications of NIOSH Method S-156 (See appendix D) under laboratory conditions for concentrations below 1 ppm. The employer has the obligation of selecting a monitoring method which meets the accuracy and precision requirements of the standard under his unique field conditions. The standard requires that methods of monitoring must be accurate, to a 95-percent confidence level, to ±35-percent for concentrations of AN at or above 2 ppm, and to ±50-percent for concentrations below 2 ppm. In addition to the methods described in appendix D, there are numerous other methods available for monitoring for AN in the workplace. Details on these other methods have been submitted by various companies to the rulemaking record, and are available at the OSHA Docket Office.
B. Since many of the duties relating to employee exposure are dependent on the results of monitoring and measuring procedures, employers shall assure that the evaluation of employee exposures is performed by a competent industrial hygienist or other technically qualified person.
v. Protective Clothing
Employees shall be provided with and required to wear appropriate protective clothing to prevent any possibility of skin contact with liquid AN. Because acrylonitrile is absorbed through the skin, it is important to prevent skin contact with liquid AN. Protective clothing shall include impermeable coveralls or similar full-body work clothing, gloves, head-coverings, as appropriate to protect areas of the body which may come in contact with liquid AN.
Employers should ascertain that the protective garmets are impermeable to acrylonitrile. Non-impermeable clothing and shoes should not be allowed to become contaminated with liquid AN. If permeable clothing does become contaminated, it should be promptly removed, placed in a regulated area for removal of the AN, and not worn again until the AN is removed. If leather footwear or other leather garments become wet from acrylonitrile, they should be replaced and not worn again, due to the ability of leather to absorb acrylonitrile and hold it against the skin. Since there is no pain associated with the blistering which may result from skin contact with liquid AN, it is essential that the employee be informed of this hazard so that he or she can be protected.
Any protective clothing which has developed leaks or is otherwise found to be defective shall be repaired or replaced. Clean protective clothing shall be provided to the employee as necessary to assure its protectiveness. Whenever impervious clothing becomes wet with liquid AN, it shall be washed down with water before being removed by the employee. Employees are also required to wear splash-proof safety goggles where there is any possibility of acrylonitrile contacting the eyes.
vi. Housekeeping and Hygiene Facilities
For purposes of complying with 29 CFR 1910.141, the following items should be emphasized:
A. The workplace should be kept clean, orderly, and in a sanitary condition. The employer is required to institute a leak and spill detection program for operations involving liquid AN in order to detect sources of fugitive AN emissions.
B. Dry sweeping and the use of compressed air is unsafe for the cleaning of floors and other surfaces where liquid AN may be found.
C. Adequate washing facilities with hot and cold water are to be provided, and maintained in a sanitary condition. Suitable cleansing agents are also to be provided to assure the effective removal of acrylonitrile from the skin.
D. Change or dressing rooms with individual clothes storage facilities must be provided to prevent the contamination of street clothes with acrylonitrile. Because of the hazardous nature of acrylonitrile, contaminated protective clothing should be placed in a regulated area designated by the employer for removal of the AN before the clothing is laundered or disposed of.
vii. Miscellaneous Precautions
A. Store acrylonitrile in tightly-closed containers in a cool, well-ventilated area and take necessary precautions to avoid any explosion hazard.
B. High exposures to acrylonitrile can occur when transferring the liquid from one container to another.
C. Non-sparking tools must be used to open and close metal acrylonitrile containers. These containers must be effectively grounded and bonded prior to pouring.
D. Never store uninhibited acrylonitrile.
E. Acrylonitrile vapors are not inhibited. They may form polymers and clog vents of storage tanks.
F. Use of supplied-air suits or other impervious coverings may be necessary to prevent skin contact with and provide respiratory protection from acrylonitrile where the concentration of acrylonitrile is unknown or is above the ceiling limit. Supplied-air suits should be selected, used, and maintained under the immediate supervision of persons knowledgeable in the limitations and potential life-endangering characteristics of supplied-air suits.
G. Employers shall advise employees of all areas and operations where exposure to acrylonitrile could occur.
viii. Common Operations
Common operations in which exposure to acrylonitrile is likely to occur include the following: Manufacture of the acrylonitrile monomer; synthesis of acrylic fibers, ABS, SAN, and nitrile barrier plastics and resins, nitrile rubber, surface coatings, specialty chemicals, use as a chemical intermediate, use as a fumigant and in the cyanoethylation of cotton.
Appendix C to § 1910.1045—Medical Surveillance Guidelines for Acrylonitrile
i. route of entry
Inhalation; skin absorption; ingestion.
ii. toxicology
Acrylonitrile vapor is an asphyxiant due to inhibitory action on metabolic enzyme systems. Animals exposed to 75 or 100 ppm for 7 hours have shown signs of anoxia; in some animals which died at the higher level, cyanomethemoglobin was found in the blood. Two human fatalities from accidental poisioning have been reported; one was caused by inhalation of an unknown concentration of the vapor, and the other was thought to be caused by skin absorption or inhalation. Most cases of intoxication from industrial exposure have been mild, with rapid onset of eye irritation, headache, sneezing, and nausea. Weakness, lightheadedness, and vomiting may also occur. Exposure to high concentrations may produce profound weakness, asphyxia, and death. The vapor is a severe eye irritant. Prolonged skin contract with the liquid may result in absorption with systemic effects, and in the formation of large blisters after a latent period of several hours. Although there is usually little or no pain or inflammation, the affected skin resembles a second-degree thermal burn. Solutions spilled on exposed skin, or on areas covered only by a light layer of clothing, evaporate rapidly, leaving no irritation, or, at the most, mild transient redness. Repeated spills on exposed skin may result in dermatitis due to solvent effects.
Results after 1 year of a planned 2-year animal study on the effects of exposure to acrylonitrile have indicated that rats ingesting as little as 35 ppm in their drinking water develop tumors of the central nervous system. The interim results of this study have been supported by a similar study being conducted by the same laboratory, involving exposure of rats by inhalation of acrylonitrile vapor, which has shown similar types of tumors in animals exposed to 80 ppm.
In addition, the preliminary results of an epidemiological study being performed by duPont on a cohort of workers in their Camden, S.C. acrylic fiber plant indicate a statistically significant increase in the incidence of colon and lung cancers among employees exposed to acrylonitrile.
iii. signs and symptoms of acute overexposure
Asphyxia and death can occur from exposure to high concentrations of acrylonitrile. Symptoms of overexposure include eye irritation, headache, sneezing, nausea and vomiting, weakness, and light-headedness. Prolonged skin contact can cause blisters on the skin with appearance of a second-degree burn, but with little or no pain. Repeated skin contact may produce scaling dermatits.
iv. treatment of acute overexposure
Remove employee from exposure. Immediately flush eyes with water and wash skin with soap or mild detergent and water. If AN has been swallowed, and person is conscious, induce vomiting. Give artificial resuscitation if indicated. More severe cases, such as those associated with loss of consciousness, may be treated by the intravenous administration of sodium nitrite, followed by sodium thiosulfate, although this is not as effective for acrylonitrile poisoning as for inorganic cyanide poisoning.
v. surveillance and preventive considerations
A. As noted above, exposure to acrylonitrile has been linked to increased incidence of cancers of the colon and lung in employees of the duPont acrylic fiber plant in Camden, S.C. In addition, the animal testing of acrylonitrile has resulted in the development of cancers of the central nervous system in rats exposed by either inhalation or ingestion. The physician should be aware of the findings of these studies in evaluating the health of employees exposed to acrylonitrile.
Most reported acute effects of occupational exposure to acrylonitrile are due to its ability to cause tissue anoxia and asphyxia. The effects are similar to those caused by hydrogen cyanide. Liquid acrylonitrile can be absorbed through the skin upon prolonged contact. The liquid readily penetrates leather, and will produce burns of the feet if footwear contaminated with acrylonitrile is not removed.
It is important for the physician to become familiar with the operating conditions in which exposure to acrylonitrile may occur. Those employees with skin diseases may not tolerate the wearing of whatever protective clothing may be necessary to protect them from exposure. In addition, those with chronic respiratory disease may not tolerate the wearing of negative-pressure respirators.
B. Surveillance and screening. Medical histories and laboratory examinations are required for each employee subject to exposure to acrylonitrile above the action level. The employer must screen employees for history of certain medical conditions which might place the employee at increased risk from exposure.
1. Central nervous system dysfunction. Acute effects of exposure to acrylonitrile generally involve the central nervous system. Symptoms of acrylonitrile exposure include headache, nausea, dizziness, and general weakness. The animal studies cited above suggest possible carcinogenic effects of acrylonitrile on the central nervous system, since rats exposed by either inhalation or ingestion have developed similar CNS tumors.
2. Respiratory disease. The du Pont data indicate an increased risk of lung cancer among employees exposed to acrylonitrile.
3. Gastrointestinal disease. The du Pont data indicate an increased risk of cancer of the colon among employees exposed to acrylonitrile. In addition, the animal studies show possible tumor production in the stomachs of the rats in the ingestion study.
4. Skin disease. Acrylonitrile can cause skin burns when prolonged skin contact with the liquid occurs. In addition, repeated skin contact with the liquid can cause dermatitis.
5. General. The purpose of the medical procedures outlined in the standard is to establish a baseline for future health monitoring. Persons unusually susceptible to the effects of anoxia or those with anemia would be expected to be at increased risk. In addition to emphasis on the CNS, respiratory and gastro-intestinal systems, the cardiovascular system, liver, and kidney function should also be stressed.
Appendix D to § 1910.1045—Sampling and Analytical Methods for Acrylonitrile
There are many methods available for monitoring employee exposures to acrylonitrile. Most of these involve the use of charcoal tubes and sampling pumps, with analysis by gas chromatograph. The essential differences between the charcoal tube methods include, among others, the use of different desorbing solvents, the use of different lots of charcoal, and the use of different equipment for analysis of the samples.
Besides charcoal, considerable work has been performed on methods using porous polymer sampling tubes and passive dosimeters. In addition, there are several portable gas analyzers and monitoring units available on the open market.
This appendix contains details for the methods which have been tested at OSHA Analytical Laboratory in Salt Lake City, and NIOSH in Cincinnati. Each is a variation on NIOSH Method S-156, which is also included for reference. This does not indicate that these methods are the only ones which will be satisfactory. There also may be workplace situations in which these methods are not adequate, due to such factors as high humidity. Copies of the other methods available to OSHA are available in the rulemaking record, and may be obtained from the OSHA Docket Office. These include, the Union Carbide, Monsanto, Dow Chemical and Dow Badische methods, as well as NISOH Method P & CAM 127.
Employers who note problems with sample breakthrough should try larger charcoal tubes. Tubes of larger capacity are available, and are often used for sampling vinyl chloride. In addition, lower flow rates and shorter sampling times should be beneficial in minimizing breakthrough problems.
Whatever method the employer chooses, he must assure himself of the method's accuracy and precision under the unique conditions present in his workplace.
NIOSH Method S-156 (Unmodified)
Analyte: Acrylonitrile.
Matrix: Air.
Procedure: Absorption on charcoal, desorption with methanol, GC.
1. Principle of the method (Reference 11.1).
1.1 A known volume of air is drawn through a charcoal tube to trap the organic vapors present.
1.2 The charcoal in the tube is transferred to a small, stoppered sample container, and the analyte is desorbed with methanol.
1.3 An aliquot of the desorbed sample is injected into a gas chromatograph.
1.4 The area of the resulting peak is determined and compared with areas obtained for standards.
2. Range and sensitivity.
2.1 This method was validated over the range of 17.5-70.0 mg/cu m at an atmospheric temperature and pressure of 22 °C and 760 MM Hg, using a 20-liter sample. Under the conditions of sample size (20-liters) the probable useful range of this method is 4.5-135 mg-cu m. The method is capable of measuring much smaller amounts if the desorption efficiency is adequate. Desorption efficiency must be determined over the range used.
2.2 The upper limit of the range of the method is dependent on the adsorptive capacity of the charcoal tube. This capacity varies with the concentrations of acrylonitrile and other substances in the air. The first section of the charcoal tube was found to hold at least 3.97 mg of acrylonitrile when a test atmosphere containing 92.0 mg/cu m of acrylonitrile in air was sampled 0.18 liter per minute for 240 minutes; at that time the concentration of acrylonitrile in the effluent was less than 5 percent of that in the influent. (The charcoal tube consists of two sections of activated charcoal separated by a section of urethane foam. See section 6.2.) If a particular atmosphere is suspected of containing a large amount of contaminant, a smaller sampling volume should be taken.
3. Interference.
3.1 When the amount of water in the air is so great that condensation actually occurs in the tube, organic vapors will not be trapped efficiently. Preliminary experiments using toluene indicate that high humidity severely decreases the breakthrough volume.
3.2 When interfering compounds are known or suspected to be present in the air, such information, including their suspected identities, should be transmitted with the sample.
3.3 It must be emphasized that any compound which has the same retention time as the analyte at the operating conditions described in this method is an interference. Retention time data on a single column cannot be considered proof of chemical identity.
3.4 If the possibility of interference exists, separation conditions (column packing, temperature, etc.) must be changed to circumvent the problem.
4. Precision and accuracy.
4.1 The Coefficient of Variation (CV T ) for the total analytical and sampling method in the range of 17.5-70.0 mg/cu m was 0.073. This value corresponds to a 3.3 mg/cu m standard deviation at the (previous) OSHA standard level (20 ppm). Statistical information and details of the validation and experimental test procedures can be found in Reference 11.2.
4.2 On the average the concentrations obtained at the 20 ppm level using the overall sampling and analytical method were 6.0 percent lower than the “true” concentrations for a limited number of laboratory experiments. Any difference between the “found” and “true” concentrations may not represent a bias in the sampling and analytical method, but rather a random variation from the experimentally determined “true” concentration. Therefore, no recovery correction should be applied to the final result in section 10.5.
5. Advantages and disadvantages of the method.
5.1 The sampling device is small, portable, and involves no liquids. Interferences are minimal, and most of those which do occur can be eliminated by altering chromatographic conditions. The tubes are analyzed by means of a quick, instrumental method.
The method can also be used for the simultaneous analysis of two or more substances suspected to be present in the same sample by simply changing gas chromatographic conditions.
5.2 One disadvantage of the method is that the amount of sample which can be taken is limited by the number of milligrams that the tube will hold before overloading. When the sample value obtained for the backup section of the charcoal tube exceeds 25 percent of that found on the front section, the possibility of sample loss exists.
5.3 Furthermore, the precision of the method is limited by the reproducibility of the pressure drop across the tubes. This drop will affect the flow rate and cause the volume to be imprecise, because the pump is usually calibrated for one tube only.
6. Apparatus.
6.1 A calibrated personal sampling pump whose flow can be determined within ±5 percent at the recommended flow rate. (Reference 11.3).
6.2 Charcoal tubes: Glass tubes with both ends flame sealed, 7 cm long with a 6-mm O.D. and a 4-mm I.D., containing 2 sections of 20/40 mesh activated charcoal separated by a 2-mm portion of urethane foam. The activated charcoals prepared from coconut shells and is fired at 600 °C prior to packing. The adsorbing section contains 100 mg of charcoal, the backup section 50 mg. A 3-mm portion of urethane foam is placed between the outlet end of the tube and the backup section. A plug of silicated glass wool is placed in front of the adsorbing section. The pressure drop across the tube must be less than 1 inch of mercury at a flow rate of 1 liter per minute.
6.3 Gas chromatograph equipped with a flame ionization detector.
6.4 Column (4-ft × 1/4 -in stainless steel) packed with 50/80 mesh Poropak, type Q.
6.5 An electronic integrator or some other suitable method for measuring peak areas.
6.6 Two-milliliter sample containers with glass stoppers or Teflon-lined caps. If an automatic sample injector is used, the associated vials may be used.
6.7 Microliter syringes: 10-microliter and other convenient sizes for making standards.
6.8 Pipets: 1.0-ml delivery pipets.
6.9 Volumetric flask: 10-ml or convenient sizes for making standard solutions.
7. Reagents.
7.1 Chromatographic quality methanol.
7.2 Acrylonitrile, reagent grade.
7.3 Hexane, reagent grade.
7.4 Purified nitrogen.
7.5 Prepurified hydrogen.
7.6 Filtered compressed air.
8. Procedure.
8.1 Cleaning of equipment. All glassware used for the laboratory analysis should be detergent washed and thoroughly rinsed with tap water and distilled water.
8.2 Calibration of personal pumps. Each personal pump must be calibrated with a representative charcoal tube in the line. This will minimize errors associated with uncertainties in the sample volume collected.
8.3 Collection and shipping of samples.
8.3.1 Immediately before sampling, break the ends of the tube to provide an opening at least one-half the internal diameter of the tube (2 mm).
8.3.2 The smaller section of charcoal is used as a backup and should be positioned nearest the sampling pump.
8.3.3 The charcoal tube should be placed in a vertical direction during sampling to minimize channeling through the charcoal.
8.3.4 Air being sampled should not be passed through any hose or tubing before entering the charcoal tube.
8.3.5 A maximum sample size of 20 liters is recommended. Sample at a flow of 0.20 liter per minute or less. The flow rate should be known with an accuracy of at least ±5 percent.
8.3.6 The temperature and pressure of the atmosphere being sampled should be recorded. If pressure reading is not available, record the elevation.
8.3.7 The charcoal tubes should be capped with the supplied plastic caps immediately after sampling. Under no circumstances should rubber caps be used.
8.3.8 With each batch of 10 samples submit one tube from the same lot of tubes which was used for sample collection and which is subjected to exactly the same handling as the samples except that no air is drawn through it. Label this as a blank.
8.3.9 Capped tubes should be packed tightly and padded before they are shipped to minimize tube breakage during shipping.
8.3.10 A sample of the bulk material should be submitted to the laboratory in a glass container with a Teflon-lined cap. This sample should not be transported in the same container as the charcoal tubes.
8.4 Analysis of samples.
8.4.1 Preparation of samples. In preparation for analysis, each charcoal tube is scored with a file in front of the first section of charcoal and broken open. The glass wool is removed and discarded. The charcoal in the first (larger) section is transferred to a 2-ml stoppered sample container. The separating section of foam is removed and discarded; the second section is transferred to another stoppered container. These two sections are analyzed separately.
8.4.2 Desorption of samples. Prior to analysis, 1.0 ml of methanol is pipetted into each sample container. Desorption should be done for 30 minutes. Tests indicate that this is adequate if the sample is agitated occasionally during this period. If an automatic sample injector is used, the sample vials should be capped as soon as the solvent is added to minimize volatilization.
8.4.3 GC conditions. The typical operating conditions for the gas chromatograph are:
1. 50 ml/min (60 psig) nitrogen carrier gas flow.
2. 65 ml/min (24 psig) hydrogen gas flow to detector.
3. 500 ml/min (50 psig) air flow to detector.
4. 235 °C injector temperature.
5. 255 °C manifold temperature (detector).
6. 155 °C column temperature.
8.4.4 Injection. The first step in the analysis is the injection of the sample into the gas chromatograph. To eliminate difficulties arising from blowback or distillation within the syringe needle, one should employ the solvent flush injection technique. The 10-microliter syringe is first flushed with solvent several times to wet the barrel and plunger. Three microliters of solvent are drawn into the syringe to increase the accuracy and reproducibility of the injected sample volume. The needle is removed from the solvent, and the plunger is pulled back about 0.2 microliter to separate the solvent flush from the sample with a pocket of air to be used as a marker. The needle is then immersed in the sample, and a 5-microliter aliquot is withdrawn, taking into consideration the volume of the needle, since the sample in the needle will be completely injected. After the needle is removed from the sample and prior to injection, the plunger is pulled back 1.2 microliters to minimize evaporation of the sample from the tip of the needle. Observe that the sample occupies 4.9-5.0 microliters in the barrel of the syringe. Duplicate injections of each sample and standard should be made. No more than a 3 percent difference in area is to be expected. An automatic sample injector can be used if it is shown to give reproducibility at least as good as the solvent flush method.
8.4.5 Measurement of area. The area of the sample peak is measured by an electronic integrator or some other suitable form of area measurement, and preliminary results are read from a standard curve prepared as discussed below.
8.5 Determination of desorption efficiency.
8.5.1 Importance of determination. The desorption efficiency of a particular compound can vary from one laboratory to another and also from one batch of charcoal to another. Thus, it is necessary to determine at least once the percentage of the specific compound that is removed in the desorption process, provided the same batch of charcoal is used.
8.5.2 Procedure for determining desorption efficiency. Activated charcoal equivalent to the amount in the first section of the sampling tube (100 mg) is measured into a 2.5 in, 4-mm I.D. glass tube, flame sealed at one end. This charcoal must be from the same batch as that used in obtaining the samples and can be obtained from unused charcoal tubes. The open end is capped with Parafilm. A known amount of hexane solution of acrylonitrile containing 0.239 g/ml is injected directly into the activated charcoal with a microliter syringe, and tube is capped with more Parafilm. When using an automatic sample injector, the sample injector vials, capped with Teflon-faced septa, may be used in place of the glass tube.
The amount injected is equivalent to that present in a 20-liter air sample at the selected level.
Six tubes at each of three levels (0.5X, 1X, and 2X of the standard) are prepared in this manner and allowed to stand for at least overnight to assure complete adsorption of the analyte onto the charcoal. These tubes are referred to as the sample. A parallel blank tube should be treated in the same manner except that no sample is added to it. The sample and blank tubes are desorbed and analyzed in exactly the same manner as the sampling tube described in section 8.4.
Two or three standards are prepared by injecting the same volume of compound into 1.0 ml of methanol with the same syringe used in the preparation of the samples. These are analyzed with the samples.
The desorption efficiency (D.E.) equals the average weight in mg recovered from the tube divided by the weight in mg added to the tube, or
The desorption efficiency is dependent on the amount of analyte collected on the charcoal. Plot the desorption efficiency versus weight of analyte found. This curve is used in section 10.4 to correct for adsorption losses.
9. Calibration and standards.
It is convenient to express concentration of standards in terms of mg/1.0 ml methanol, because samples are desorbed in this amount of methanol. The density of the analyte is used to convert mg into microliters for easy measurement with a microliter syringe. A series of standards, varying in concentration over the range of interest, is prepared and analyzed under the same GC conditions and during the same time period as the unknown samples. Curves are established by plotting concentration in mg/1.0 ml versus peak area.
10. Calculations.
10.1 Read the weight, in mg, corresponding to each peak area from the standard curve. No volume corrections are needed, because the standard curve is based on mg/1.0 ml methanol and the volume of sample injected is identical to the volume of the standards injected.
10.2 Corrections for the bank must be made for each sample.
mg = mg sample−mg blank
Where:
mg sample = mg found in front section of sample tube.
mg sample = mg found in front section of blank tube.
A similar procedure is followed for the backup sections.
10.3 Add the weights found in the front and backup sections to get the total weight in the sample.
10.4 Read the desorption efficiency from the curve (see sec. 8.5.2) for the amount found in the front section. Divide the total weight by this desorption efficiency to obtain the corrected mg/sample.
10.5 The concentration of the analyte in the air sampled can be expressed in mg/cu m.
10.6 Another method of expressing concentration is ppm.
ppm = m mg/cu × 24.45/M.W. × 760/P × T. + 273/298
Where:
P
T
24.45 = Molar volume (liter/mole) at 25 °C and 760 mm Hg.
M.W.
760 = Standard pressure (mm Hg).
298 = Standard temperature (°K).
11. References.
11.1 White, L. D. et al., “A Convenient Optimized Method for the Analysis of Selected Solvent Vapors in the Industrial Atmosphere,” Amer. Ind. Hyg. Assoc. J., 31: 225 (1970).
11.2 Documentation of NIOSH Validation Tests, NIOSH Contract No. CDC-99-74-45.
11.3 Final Report, NIOSH Contract HSM-99-71-31, “Personal Sampler Pump for Charcoal Tubes,” September 15, 1972.
NIOSH Modification of NIOSH Method S-156
The NIOSH recommended method for low levels for acrylonitrile is a modification of method S-156. It differs in the following respects:
Column: 20 percent SP-1000 on 80/100 Supelcoport 10 feet × 1/8 inch S.S.
Conditions:
Injector temperature: 200 °C.
Detector temperature: 100 °C.
Column temperature: 85 °C.
Helium flow: 25 ml/min.
Air flow: 450 ml/min.
Hydrogen flow: 55 ml/min.
µl injection of the desorbed analyte is used.
[43 FR 45809, Oct. 3, 1978, as amended at 45 FR 35283, May 23, 1980; 54 FR 24334, June 7, 1989; 58 FR 35310, June 30, 1993; 61 FR 5508, Feb. 13, 1996; 63 FR 1291, Jan. 8, 1998; 63 FR 20099, Apr. 23, 1998; 70 FR 1142, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50190, Aug. 24, 2006; 73 FR 75586, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR 17783, Mar. 26, 2012; 84 FR 21518, May 14, 2019]
OSHA Laboratory Modification of NIOSH Method S-156
Analyte: Acrylonitrile.
Matrix: Air.
Procedure: Adsorption on charcoal, desorption with methanol, GC.
1. Principle of the Method (Reference 1).
1.1 A known volume of air is drawn through a charcoal tube to trap the organic vapors present.
1.2 The charcoal in the tube is transferred to a small, stoppered sample vial, and the analyte is desorbed with methanol.
1.3 An aliquot of the desorbed sample is injected into a gas chromatograph.
1.4 The area of the resulting peak is determined and compared with areas obtained for standards.
2. Advantages and disadvantages of the method.
2.1 The sampling device is small, portable, and involves no liquids. Interferences are minimal, and most of those which do occur can be eliminated by altering chromatographic conditions. The tubes are analyzed by means of a quick, instrumental method.
2.2 This method may not be adequate for the simultaneous analysis of two or more substances.
2.3 The amount of sample which can be taken is limited by the number of milligrams that the tube will hold before overloading. When the sample value obtained for the backup section of the charcoal tube exceeds 25 percent of that found on the front section, the possibility of sample loss exists.
2.4 The precision of the method is limited by the reproducibility of the pressure drop across the tubes. This drop will affect the flow rate and cause the volume to be imprecise, because the pump is usually calibrated for one tube only.
3. Apparatus.
3.1 A calibrated personal sampling pump whose flow can be determined within ±5 percent at the recommended flow rate.
3.2 Charcoal tubes: Glass tube with both ends flame sealed, 7 cm long with a 6-mm O.D. and a 4-mm I.D., containing 2 sections of 20/40 mesh activated charcoal separated by a 2-mm portion of urethane foam. The activated charcoal is prepared from coconut shells and is fired at 600 °C prior to packing. The adsorbing section contains 100 mg of charcoal, the back-up section 50 mg. A 3-mm portion of urethane foam is placed between the outlet end of the tube and the back-up section. A plug of sililated glass wool is placed in front of the adsorbing section. The pressure drop across the tube must be less than one inch of mercury at a flow rate of 1 liter per minute.
3.3 Gas chromatograph equipped with a nitrogen phosphorus detector.
3.4 Column (10-ft × 1/8″-in stainless steel) packed with 100/120 Supelcoport coated with 10 percent SP 1000.
3.5 An electronic integrator or some other suitable method for measuring peak area.
3.6 Two-milliliter sample vials with Teflon-lined caps
3.7 Microliter syringes: 10-microliter, and other convenient sizes for making standards.
3.8 Pipets: 1.0-ml delivery pipets.
3.9 Volumetric flasks: convenient sizes for making standard solutions.
4. Reagents.
4.1 Chromatographic quality methanol.
4.2 Acrylonitrile, reagent grade.
4.3 Filtered compressed air.
4.4 Purified hydrogen.
4.5 Purified helium.
5. Procedure.
5.1 Cleaning of equipment. All glassware used for the laboratory analysis should be properly cleaned and free of organics which could interfere in the analysis.
5.2 Calibration of personal pumps. Each pump must be calibrated with a representative charcoal tube in the line.
5.3 Collection and shipping of samples.
5.3.1 Immediately before sampling, break the ends of the tube to provide an opening at least one-half the internal diameter of the tube (2 mm).
5.3.2 The smaller section of the charcoal is used as the backup and should be placed nearest the sampling pump.
5.3.3 The charcoal should be placed in a vertical position during sampling to minimize channeling through the charcoal.
5.3.4 Air being sampled should not be passed through any hose or tubing before entering the charcoal tube.
5.3.5 A sample size of 20 liters is recommended. Sample at a flow rate of approximately 0.2 liters per minute. The flow rate should be known with an accuracy of at least ±5 percent.
5.3.6 The temperature and pressure of the atmosphere being sampled should be recorded.
5.3.7 The charcoal tubes should be capped with the supplied plastic caps immediately after sampling. Rubber caps should not be used.
5.3.8 Submit at least one blank tube (a charcoal tube subjected to the same handling procedures, without having any air drawn through it) with each set of samples.
5.3.9. Take necessary shipping and packing precautions to minimize breakage of samples.
5.4 Analysis of samples.
5.4.1 Preparation of samples. In preparation for analysis, each charcoal tube is scored with a file in front of the first section of charcoal and broken open. The glass wool is removed and discarded. The charcoal in the first (larger) section is transferred to a 2-ml vial. The separating section of foam is removed and discarded; the section is transferred to another capped vial. These two sections are analyzed separately.
5.4.2 Desorption of samples. Prior to analysis, 1.0 ml of methanol is pipetted into each sample container. Desorption should be done for 30 minutes in an ultrasonic bath. The sample vials are recapped as soon as the solvent is added.
5.4.3 GC conditions. The typical operating conditions for the gas chromatograph are:
1. 30 ml/min (60 psig) helium carrier gas flow.
2. 3.0 ml/min (30 psig) hydrogen gas flow to detector.
3. 50 ml/min (60 psig) air flow to detector.
4. 200 °C injector temperature.
5. 200 °C dejector temperature.
6. 100 °C column temperature.
5.4.4 Injection. Solvent flush technique or equivalent.
5.4.5 Measurement of area. The area of the sample peak is measured by an electronic integator or some other suitable form of area measurement, and preliminary results are read from a standard curve prepared as discussed below.
5.5 Determination of desorption efficiency.
5.5.1 Importance of determination. The desorption efficiency of a particular compound can vary from one laboratory to another and also from one batch of charcoal to another. Thus, it is necessary to determine, at least once, the percentage of the specific compound that is removed in the desorption process, provided the same batch of charcoal is used.
5.5.2 Procedure for determining desorption efficiency. The reference portion of the charcoal tube is removed. To the remaining portion, amounts representing 0.5X, 1X, and 2X (X represents TLV) based on a 20 l air sample are injected onto several tubes at each level. Dilutions of acrylonitrile with methanol are made to allow injection of measurable quantities. These tubes are then allowed to equilibrate at least overnight. Following equilibration they are analyzed following the same procedure as the samples A curve of the desorption efficiency amt recovered/amt added is plotted versus amount of analyte found. This curve is used to correct for adsorption losses.
6. Calibration and standards.
A series of standards, varying in concentration over the range of interest, is prepared and analyzed under the same GC conditions and during the same time period as the unknown samples. Curves are prepared by plotting concentration versus peak area.
7. Calculations.
Read the weight, corresponding to each peak area from the standard curve, correct for the blank, correct for the desorption efficiency, and make necessary air volume corrections.
8. Reference. NIOSH Method S-156.
For the purpose of this section, the following definitions shall apply:
Action level means a concentration of airborne EtO of 0.5 ppm calculated as an eight (8)-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer whose duties require the person to enter a regulated area, or any person entering such an area as a designated representative of employees for the purpose of exercising the right to observe monitoring and measuring procedures under paragraph (l) of this section, or any other person authorized by the Act or regulations issued under the Act.
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment that is likely to or does result in an unexpected significant release of EtO.
Employee exposure means exposure to airborne EtO which would occur if the employee were not using respiratory protective equipment.
Ethylene oxide or EtO means the three-membered ring organic compound with chemical formula C 2 H 4 O.
The employer shall ensure that no employee is exposed to an airborne concentration of EtO in excess of one (1) part EtO per million parts of air (1 ppm) as an 8-hour time-weighted average (8-hour TWA).
The employer shall ensure that no employee is exposed to an airborne concentration of EtO in excess of 5 parts of EtO per million parts of air (5 ppm) as averaged over a sampling period of fifteen (15) minutes.
Notwithstanding the provisions of paragraph (d)(4) of this section, the employer shall institute the exposure monitoring required under paragraphs (d)(2)(i) and (d)(3) of this section whenever there has been a change in the production, process, control equipment, personnel or work practices that may result in new or additional exposures to EtO or when the employer has any reason to suspect that a change may result in new or additional exposures.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer must implement a respiratory protection program in accordance with § 1910.134(b) through (d) (except (d)(i)(iii)), and (f) through (m), which covers each employee required by this section to use a respirator.
Employers must:
When employees could have eye or skin contact with EtO or EtO solutions, the employer must select and provide, at no cost to the employee, appropriate protective clothing or other equipment in accordance with 29 CFR 1910.132 and 1910.133 to protect any area of the employee's body that may come in contact with the EtO or EtO solution, and must ensure that the employee wears the protective clothing and equipment provided.
Where there is the possibility of employee exposure to EtO due to an emergency, means shall be developed to alert potentially affected employees of such occurrences promptly. Affected employees shall be immediately evacuated from the area in the event that an emergency occurs.
The employer shall ensure that all medical examinations and procedures are performed by or under the supervision of a licensed physician, and are provided without cost to the employee, without loss of pay, and at a reasonable time and place.
The employer shall make available medical examinations and consultations to each employee covered under paragraph (i)(1)(i) of this section on the following schedules:
The employer shall provide the following information to the examining physician:
DANGER
ETHYLENE OXIDE
MAY CAUSE CANCER
MAY DAMAGE FERTILITY OR THE UNBORN CHILD
RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING MAY BE REQUIRED IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
ETHYLENE OXIDE
CANCER HAZARD AND REPRODUCTIVE HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE CLOTHING MAY BE REQUIRED TO BE WORN IN THIS AREA
1
CONTAINS ETHYLENE OXIDE
CANCER HAZARD AND REPRODUCTIVE HAZARD;
2
The employer shall comply with the requirements concerning transfer of records set forth in 29 CFR 1910.1020(h).
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to EtO conducted in accordance with paragraph (d) of this section.
When observation of the monitoring of employee exposure to EtO requires entry into an area where the use of protective clothing or equipment is required, the observer shall be provided with and be required to use such clothing and equipment and shall comply with all other applicable safety and health procedures.
The information contained in the appendices is not intended by itself to create any additional obligations not otherwise imposed or to detract from any existing obligation.
Appendix A to § 1910.1047—Substance Safety Data Sheet for Ethylene Oxide (Non-Mandatory)
i. Substance Identification
A. Substance: Ethylene oxide (C 2 H 4 O).
B. Synonyms: dihydrooxirene, dimethylene oxide, EO, 1,2-epoxyethane, EtO, ETO, oxacyclopropane, oxane, oxidoethane, alpha/beta-oxidoethane, oxiran, oxirane.
C. Ethylene oxide can be found as a liquid or vapor.
D. EtO is used in the manufacture of ethylene glycol, surfactants, ethanolamines, glycol ethers, and other organic chemicals. EtO is also used as a sterilant and fumigant.
E. Appearance and odor: Colorless liquid below 10.7 °C (51.3 °F) or colorless gas with ether-like odor detected at approximately 700 parts EtO per million parts of air (700 ppm).
F. Permissible Exposure: Exposure may not exceed 1 part EtO per million parts of air averaged over the 8-hour workday.
ii. Health Hazard Data
A. Ethylene oxide can cause bodily harm if you inhale the vapor, if it comes into contact with your eyes or skin, or if you swallow it.
B. Effects of overexposure:
1. Ethylene oxide in liquid form can cause eye irritation and injury to the cornea, frostbite, and severe irritation and blistering of the skin upon prolonged or confined contact. Ingestion of EtO can cause gastric irritation and liver injury. Acute effects from inhalation of EtO vapors include respiratory irritation and lung injury, headache, nausea, vomiting, diarrhea, shortness of breath, and cyaonosis (blue or purple coloring of skin). Exposure has also been associated with the occurrence of cancer, reproductive effects, mutagenic changes, neurotoxicity, and sensitization.
1. EtO has been shown to cause cancer in laboratory animals and has been associated with higher incidences of cancer in humans. Adverse reproductive effects and chromosome damage may also occur from EtO exposure.
a. Reporting signs and symptoms: You should inform your employer if you develop any signs or symptoms and suspect that they are caused by exposure to EtO.
iii. Emergency First Aid Procedures
A. Eye exposure: If EtO gets into your eyes, wash your eyes immediately with large amounts of water, lifting the lower and upper eyelids. Get medical attention immediately. Contact lenses should not be worn when working with this chemical.
B. Skin exposure: If EtO gets on your skin, immediately wash the contaminated skin with water. If EtO soaks through your clothing, especially your shoes, remove the clothing immediately and wash the skin with water using an emergency deluge shower. Get medical attention immediately. Thoroughly wash contaminated clothing before reusing. Contaminated leather shoes or other leather articles should not be reused and should be discarded.
C. Inhalation: If large amounts of EtO are inhaled, the exposed person must be moved to fresh air at once. If breathing has stopped, perform cardiopulmonary resuscitation. Keep the affected person warm and at rest. Get medical attention immediately.
D. Swallowing: When EtO has been swallowed, give the person large quantities of water immediately. After the water has been swallowed, try to get the person to vomit by having him or her touch the back of the throat with his or her finger. Do not make an unconscious person vomit. Get medical attention immediately.
E. Rescue: Move the affected person from the hazardous exposure. If the exposed person has been overcome, attempt rescue only after notifying at least one other person of the emergency and putting into effect established emergency procedures. Do not become a casualty yourself. Understand your emergency rescue procedures and know the location of the emergency equipment before the need arises.
iv. Respirators and Protective Clothing
A. Respirators. You may be required to wear a respirator for nonroutine activities, in emergencies, while your employer is in the process of reducing EtO exposures through engineering controls, and in areas where engineering controls are not feasible. As of the effective date of this standard, only air-supplied, positive-pressure, full-facepiece respirators are approved for protection against EtO. If air-purifying respirators are worn in the future, they must have a label issued by the National Institute for Occupational Safety and Health under the provisions of 42 CFR part 84 stating that the respirators have been approved for use with ethylene oxide. For effective protection, respirators must fit your face and head snugly. Respirators must not be loosened or removed in work situations where their use is required.
EtO does not have a detectable odor except at levels well above the permissible exposure limits. If you can smell EtO while wearing a respirator, proceed immediately to fresh air. If you experience difficulty breathing while wearing a respirator, tell your employer.
B. Protective clothing: You may be required to wear impermeable clothing, gloves, a face shield, or other appropriate protective clothing to prevent skin contact with liquid EtO or EtO-containing solutions. Where protective clothing is required, your employer must provide clean garments to you as necessary to assure that the clothing protects you adequately.
Replace or repair protective clothing that has become torn or otherwise damaged.
EtO must never be allowed to remain on the skin. Clothing and shoes which are not impermeable to EtO should not be allowed to become contaminated with EtO, and if they do, the clothing should be promptly removed and decontaminated. Contaminated leather shoes should be discarded. Once EtO penetrates shoes or other leather articles, they should not be worn again.
C. Eye protection: You must wear splashproof safety goggles in areas where liquid EtO or EtO-containing solutions may contact your eyes. In addition, contact lenses should not be worn in areas where eye contact with EtO can occur.
v. Precautions for Safe Use, Handling, and Storage
A. EtO is a flammable liquid, and its vapors can easily form explosive mixtures in air.
B. EtO must be stored in tighly closed containers in a cool, well-ventilated area, away from heat, sparks, flames, strong oxidizers, alkalines, and acids, strong bases, acetylide-forming metals such as cooper, silver, mercury and their alloys.
C. Sources of ignition such as smoking material, open flames and some electrical devices are prohibited wherever EtO is handled, used, or stored in a manner that could create a potential fire or explosion hazard.
D. You should use non-sparking tools when opening or closing metal containers of EtO, and containers must be bonded and grounded in the rare instances in which liquid EtO is poured or transferred.
E. Impermeable clothing wet with liquid EtO or EtO-containing solutions may be easily ignited. If your are wearing impermeable clothing and are splashed with liquid EtO or EtO-containing solution, you should immediately remove the clothing while under an emergency deluge shower.
F. If your skin comes into contact with liquid EtO or EtO-containing solutions, you should immediately remove the EtO using an emergency deluge shower.
G. You should not keep food, beverages, or smoking materials in regulated areas where employee exposures are above the permissible exposure limits.
H. Fire extinguishers and emergency deluge showers for quick drenching should be readily available, and you should know where they are and how to operate them.
I. Ask your supervisor where EtO is used in your work area and for any additional plant safety and health rules.
vi. Access to Information
A. Each year, your employer is required to inform you of the information contained in this standard and appendices for EtO. In addition, your employer must instruct you in the proper work practices for using EtO emergency procedures, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being exposed to EtO. You or your representative has the right to observe employee measurements and to record the results obtained. Your employer is required to inform you of your exposure. If your employer determine that you are being overexposed, he or she is required to inform you of the actions which are being taken to reduce your exposure to within permissible exposure limits.
C. Your employer is required to keep records of your exposures and medical examinations. These exposure records must be kept by the employer for at least thirty (30) years. Medical records must be kept for the period of your employment plus thirty (30) years.
D. Your employer is required to release your exposure and medical records to your physician or designated representative upon your written request.
vii. Sterilant Use of Eto in Hospitals and Health Care Facilities
This section of appendix A, for informational purposes, sets forth EPA's recommendations for modifications in workplace design and practice in hospitals and health care facilities for which the Environmental Protection Agency has registered EtO for uses as a sterilant or fumigant under the Federal Insecticide, Funigicide, and Rodenticide Act, 7 U.S.C. 136 et seq. These new recommendations, published in the Federal Register by EPA at 49 FR 15268, as modified in today's Register, are intended to help reduce the exposure of hospital and health care workers to EtO to 1 ppm. EPA's recommended workplace design and workplace practice are as follows:
1. Workplace Design
a. Installation of gas line hand valves. Hand valves must be installed on the gas supply line at the connection to the supply cylinders to minimize leakage during cylinder change.
b. Installation of capture boxes. Sterilizer operations result in a gas/water discharge at the completion of the process. This discharge is routinely piped to a floor drain which is generally located in an equipment or an adjacent room. When the floor drain is not in the same room as the sterilizer and workers are not normally present, all that is necessary is that the room be well ventilated.
The installation of a “capture box” will be required for those work place layouts where the floor drain is located in the same room as the sterilizer or in a room where workers are normally present. A “capture box” is a piece of equipment that totally encloses the floor drain where the discharge from the sterilizer is pumped. The “capture box” is to be vented directly to a non-recirculating or dedicated ventilation system. Sufficient air intake should be allowed at the bottom of the box to handle the volume of air that is ventilated from the top of the box. The “capture box” can be made of metal, plastic, wood or other equivalent material. The box is intended to reduce levels of EtO discharged into the work room atmosphere. The use of a “capture box” is not required if: (1) The vacuum pump discharge floor drain is located in a well ventilated equipment or other room where workers are not normally present or (2) the water sealed vacuum pump discharges directly to a closed sealed sewer line (check local plumbing codes).
If it is impractical to install a vented “capture box” and a well ventilated equipment or other room is not feasible, a box that can be sealed over the floor drain may be used if: (1) The floor drain is located in a room where workers are not normally present and EtO cannot leak into an occupied area, and (2) the sterilizer in use is less than 12 cubic feet in capacity (check local plumbing codes).
c. Ventilation of aeration units i. Existing aeration units. Existing units must be vented to a non-recirculating or dedicated system or vented to an equipment or other room where workers are not normally present and which is well ventilated. Aerator units must be positioned as close as possible to the sterilizer to minimize the exposure from the off-gassing of sterilized items.
ii. Installation of new aerator units (where none exist). New aerator units must be vented as described above for existing aerators. Aerators must be in place by July 1, 1986.
d. Ventilation during cylinder change. Workers may be exposed to short but relatively high levels of EtO during the change of gas cylinders. To reduce exposure from this route, users must select one of three alternatives designed to draw off gas that may be released when the line from the sterilizer to the cylinder is disconnected:
i. Location of cylinders in a well ventilated equipment room or other room where workers are not normally present.
ii. Installation of a flexible hose (at least 4″ in diameter) to a non-recirculating or dedicated ventilation system and located in the area of cylinder change in such a way that the hose can be positioned at the point where the sterilizer gas line is disconnected from the cylinder.
iii. Installation of a hood that is part of a non-recirculating or dedicated system and positioned no more than one foot above the point where the change of cylinders takes place.
e. Ventilation of sterilizer door area. One of the major sources of exposure to EtO occurs when the sterilizer door is opened following the completion of the sterilization process. In order to reduce this avenue of exposure, a hood or metal canopy closed on each end must be installed over the sterilizer door. The hood or metal canopy must be connected to a non-recirculating or dedicated ventilation system or one that exhausts gases to a well ventilated equipment or other room where workers are not normally present. A hood or canopy over the sterilizer door is required for use even with those sterilizers that have a purge cycle and must be in place by July 1, 1986.
f. Ventilation of sterilizer relief valve. Sterilizers are typically equipped with a safety relief device to release gas in case of increased pressure in the sterilizer. Generally, such relief devices are used on pressure vessels. Although these pressure relief devices are rarely opened for hospital and health care sterilizers, it is suggested that they be designed to exhaust vapor from the sterilizer by one of the following methods:
i. Through a pipe connected to the outlet of the relief valve ventilated directly outdoors at a point high enough to be away from passers by, and not near any windows that open, or near any air conditioning or ventilation air intakes.
ii. Through a connection to an existing or new non-recirculating or dedicated ventilation system.
iii. Through a connection to a well ventilated equipment or other room where workers are not normally present.
g. Ventilation systems. Each hospital and health care facility affected by this notice that uses EtO for the sterilization of equipment and supplies must have a ventilation system which enables compliance with the requirements of section (b) through (f) in the manner described in these sections and within the timeframes allowed. Thus, each affected hospital and health care facility must have or install a non-recirculating or dedicated ventilation equipment or other room where workers are not normally present in which to vent EtO.
h. Installation of alarm systems. An audible and visual indicator alarm system must be installed to alert personnel of ventilation system failures, i.e., when the ventilation fan motor is not working.
2. Workplace Practices
All the workplace practices discussed in this unit must be permanently posted near the door of each sterilizer prior to use by any operator.
a. Changing of supply line filters. Filters in the sterilizer liquid line must be changed when necessary, by the following procedure:
i. Close the cylinder valve and the hose valve.
ii. Disconnect the cylinder hose (piping) from the cylinder.
iii. Open the hose valve and bleed slowly into a proper ventilating system at or near the in-use supply cylinders.
iv. Vacate the area until the line is empty.
v. Change the filter.
vi. Reconnect the lines and reverse the value position.
vii. Check hoses, filters, and valves for leaks with a fluorocarbon leak detector (for those sterilizers using the 88 percent chlorofluorocarbon, 12 percent ethylene oxide mixture (12/88)).
b. Restricted access area. i. Areas involving use of EtO must be designated as restricted access areas. They must be identified with signs or floor marks near the sterilizer door, aerator, vacuum pump floor drain discharge, and in-use cylinder storage.
ii. All personnel must be excluded from the restricted area when certain operations are in progress, such as discharging a vacuum pump, emptying a sterilizer liquid line, or venting a non-purge sterilizer with the door ajar or other operations where EtO might be released directly into the face of workers.
c. Door opening procedures. i. Sterilizers with purge cycles. A load treated in a sterilizer equipped with a purge cycle should be removed immediately upon completion of the cycle (provided no time is lost opening the door after cycle is completed). If this is not done, the purge cycle should be repeated before opening door.
ii. Sterilizers without purge cycles. For a load treated in a sterilizer not equipped with a purge cycle, the sterilizer door must be ajar 6″ for 15 minutes, and then fully opened for at least another 15 minutes before removing the treated load. The length of time of the second period should be established by peak monitoring for one hour after the two 15-minute periods suggested. If the level is above 10 ppm time-weighted average for 8 hours, more time should be added to the second waiting period (door wide open). However, in no case may the second period be shortened to less than 15 minutes.
d. Chamber unloading procedures. i. Procedures for unloading the chamber must include the use of baskets or rolling carts, or baskets and rolling tables to transfer treated loads quickly, thus avoiding excessive contact with treated articles, and reducing the duration of exposures.
ii. If rolling carts are used, they should be pulled not pushed by the sterilizer operators to avoid offgassing exposure.
e. Maintenance. A written log should be instituted and maintained documenting the date of each leak detection and any maintenance procedures undertaken. This is a suggested use practice and is not required.
i. Leak detection. Sterilizer door gaskets, cylinder and vacuum piping, hoses, filters, and valves must be checked for leaks under full pressure with a Fluorocarbon leak detector (for 12/88 systems only) every two weeks by maintenance personnel. Also, the cylinder piping connections must be checked after changing cylinders. Particular attention in leak detection should be given to the automatic solenoid valves that control the flow of EtO to the sterilizer. Specifically, a check should be made at the EtO gasline entrance port to the sterilizer, while the sterilizer door is open and the solenoid valves are in a closed position.
ii. Maintenance procedures. Sterilizer/areator door gaskets, valves, and fittings must be replaced when necessary as determined by maintenance personnel in their bi-weekly checks; in addition, visual inspection of the door gaskets for cracks, debris, and other foreign substances should be conducted daily by the operator.
Appendix B to § 1910.1047—Substance Technical Guidelines for Ethylene Oxide (Non-Mandatory)
i. Physical and Chemical Data
A. Substance identification:
1. Synonyms: dihydrooxirene, dimethylene oxide, EO, 1,2-epoxyethane, EtO ETO oxacyclopropane, oxane, oxidoethane, alpha/beta-oxidoethane, oxiran, oxirane.
2. Formula: (C 2 H 4 O).
3. Molecular weight: 44.06
B. Physical data:
1. Boiling point (760 mm Hg): 10.70 °C (51.3 °F);
2. Specific gravity (water = 1): 0.87 (at 20 °C or 68 °F)
3. Vapor density (air = 1): 1.49;
4. Vapor pressure (at 20 °C); 1,095 mm Hg;
5. Solubility in water: complete;
6. Appearance and odor: colorless liquid; gas at temperature above 10.7 °F or 51.3 °C with ether-like odor above 700 ppm.
ii. Fire, Explosion, and Reactivity Hazard Data
A. Fire:
1. Flash point: less than O °F (open cup);
2. Stability: decomposes violently at temperatures above 800 °F;
3. Flammable limits in air, percent by volume: Lower: 3, Upper: 100;
4. Extinguishing media: Carbon dioxide for small fires, polymer or alcohol foams for large fires;
5. Special fire fighting procedures: Dilution of ethylene oxide with 23 volumes of water renders it non-flammable;
6. Unusual fire and explosion hazards: Vapors of EtO will burn without the presence of air or other oxidizers. EtO vapors are heavier than air and may travel along the ground and be ignited by open flames or sparks at locations remote from the site at which EtO is being used.
7. For purposes of compliance with the requirements of 29 CFR 1910.106, EtO is classified as a flammable gas. For example, 7,500 ppm, approximately one-fourth of the lower flammable limit, would be considered to pose a potential fire and explosion hazard.
8. For purposes of compliance with 29 CFR 1910.155, EtO is classified as a Class B fire hazard.
9. For purpose of compliance with 29 CFR 1919.307, locations classified as hazardous due to the presence of EtO shall be Class I.
B. Reactivity:
1. Conditions contributing to instability: EtO will polymerize violently if contaminated with aqueous alkalies, amines, mineral acids, metal chlorides, or metal oxides. Violent decomposition will also occur at temperatures above 800 °F;
2. Incompatabilities: Alkalines and acids;
3. Hazardous decomposition products: Carbon monoxide and carbon dioxide.
iii. Spill, Leak, and Disposal Procedures
A. If EtO is spilled or leaked, the following steps should be taken:
1. Remove all ignition sources.
2. The area should be evacuated at once and re-entered only after the area has been thoroughly ventilated and washed down with water.
B. Persons not wearing appropriate protective equipment should be restricted from areas of spills or leaks until cleanup has been completed.
C. Waste disposal methods: Waste material should be disposed of in a manner that is not hazardous to employees or to the general population. In selecting the method of waste disposal, applicable local, State, and Federal regulations should be consulted.
iv. Monitoring and Measurement Procedures
A. Exposure above the Permissible Exposure Limit:
1. Eight-hour exposure evaluation: Measurements taken for the purpose of determining employee exposure under this section are best taken with consecutive samples covering the full shift. Air samples should be taken in the employee's breathing zone (air that would most nearly represent that inhaled by the employee.)
2. Monitoring techniques: The sampling and analysis under this section may be performed by collection of the EtO vapor on charcoal adsorption tubes or other composition adsorption tubes, with subsequent chemical analysis. Sampling and analysis may also be performed by instruments such as real-time continuous monitoring systems, portable direct reading instruments, or passive dosimeters as long as measurements taken using these methods accurately evaluate the concentration of EtO in employees' breathing zones.
Appendix D describes the validated method of sampling and analysis which has been tested by OSHA for use with EtO. Other available methods are also described in appendix D. The employer has the obligation of selecting a monitoring method which meets the accuracy and precision requirements of the standard under his unique field conditions. The standard requires that the method of monitoring should be accurate, to a 95 percent confidence level, to plus or minus 25 percent for concentrations of EtO at 1 ppm, and to plus or minus 35 percent for concentrations at 0.5 ppm. In addition to the method described in appendix D, there are numerous other methods available for monitoring for EtO in the workplace. Details on these other methods have been submitted by various companies to the rulemaking record, and are available at the OSHA Docket Office.
B. Since many of the duties relating to employee exposure are dependent on the results of measurement procedures, employers should assure that the evaluation of employee exposures is performed by a technically qualified person.
v. Protective Clothing and Equipment
Employees should be provided with and be required to wear appropriate protective clothing wherever there is significant potential for skin contact with liquid EtO or EtO-containing solutions. Protective clothing shall include impermeable coveralls or similar full-body work clothing, gloves, and head coverings, as appropriate to protect areas of the body which may come in contact with liquid EtO or EtO-containing solutions.
Employers should ascertain that the protective garments are impermeable to EtO. Permeable clothing, including items made of rubber, and leather shoes should not be allowed to become contaminated with liquid EtO. If permeable clothing does become contaminated, it should be immediately removed, while the employer is under an emergency deluge shower. If leather footwear or other leather garments become wet from EtO they should be discarded and not be worn again, because leather absorbs EtO and holds it against the skin.
Any protective clothing that has been damaged or is otherwise found to be defective should be repaired or replaced. Clean protective clothing should be provided to the employee as necessary to assure employee protection. Whenever impermeable clothing becomes wet with liquid EtO, it should be washed down with water before being removed by the employee. Employees are also required to wear splash-proof safety goggles where there is any possibility of EtO contacting the eyes.
vi. Miscellaneous Precautions
A. Store EtO in tightly closed containers in a cool, well-ventilated area and take all necessary precautions to avoid any explosion hazard.
B. Non-sparking tools must be used to open and close metal containers. These containers must be effectively grounded and bonded.
C. Do not incinerate EtO cartridges, tanks or other containers.
D. Employers should advise employees of all areas and operations where exposure to EtO occur.
vii. Common Operations
Common operations in which exposure to EtO is likely to occur include the following: Manufacture of EtO, surfactants, ethanolamines, glycol ethers, and specialty chemicals, and use as a sterilant in the hospital, health product and spice industries.
Appendix C to § 1910.1047—Medical Surveillance Guidelines for Ethylene Oxide (Non-Mandatory)
i. route of entry
Inhalation.
ii. toxicology
Clinical evidence of adverse effects associated with the exposure to EtO is present in the form of increased incidence of cancer in laboratory animals (leukemia, stomach, brain), mutation in offspring in animals, and resorptions and spontaneous abortions in animals and human populations respectively. Findings in humans and experimental animals exposed to airborne concentrations of EtO also indicate damage to the genetic material (DNA). These include hemoglobin alkylation, unsecheduled DNA synthesis, sister chromatid exchange chromosomal aberration, and functional sperm abnormalities.
Ethylene oxide in liquid form can cause eye irritation and injury to the cornea, frostbite, severe irritation, and blistering of the skin upon prolonged or confined contact. Ingestion of EtO can cause gastric irritation and liver injury. Other effects from inhalation of EtO vapors include respiratory irritation and lung injury, headache, nausea, vomiting, diarrhea, dyspnea and cyanosis.
iii. signs and symptoms of acute overexposure
The early effects of acute overexposure to EtO are nausea and vomiting, headache, and irritation of the eyes and respiratory passages. The patient may notice a “peculiar taste” in the mouth. Delayed effects can include pulmonary edema, drowsiness, weakness, and incoordination. Studies suggest that blood cell changes, an increase in chromosomal aberrations, and spontaneous abortion may also be causally related to acute overexposure to EtO.
Skin contact with liquid or gaseous EtO causes characteristic burns and possibly even an allergic-type sensitization. The edema and erythema occurring from skin contact with EtO progress to vesiculation with a tendency to coalesce into blebs with desquamation. Healing occurs within three weeks, but there may be a residual brown pigmentation. A 40-80% solution is extremely dangerous, causing extensive blistering after only brief contact. Pure liquid EtO causes frostbite because of rapid evaporation. In contrast, the eye is relatively insensitive to EtO, but there may be some irritation of the cornea.
Most reported acute effects of occupational exposure to EtO are due to contact with EtO in liquid phase. The liquid readily penetrates rubber and leather, and will produce blistering if clothing or footwear contaminated with EtO are not removed.
iv. surveillance and preventive considerations
As noted above, exposure to EtO has been linked to an increased risk of cancer and reproductive effects including decreased male fertility, fetotoxicity, and spontaneous abortion. EtO workers are more likely to have chromosomal damage than similar groups not exposed to EtO. At the present, limited studies of chronic effects in humans resulting from exposure to EtO suggest a causal association with leukemia. Animal studies indicate leukemia and cancers at other sites (brain, stomach) as well. The physician should be aware of the findings of these studies in evaluating the health of employees exposed to EtO.
Adequate screening tests to determine an employee's potential for developing serious chronic diseases, such as cancer, from exposure to EtO do not presently exist. Laboratory tests may, however, give evidence to suggest that an employee is potentially overexposed to EtO. It is important for the physician to become familiar with the operating conditions in which exposure to EtO is likely to occur. The physician also must become familiar with the signs and symptoms that indicate a worker is receiving otherwise unrecognized and unacceptable exposure to EtO. These elements are especially important in evaluating the medical and work histories and in conducting the physical exam. When an unacceptable exposure in an active employee is identified by the physician, measures taken by the employer to lower exposure should also lower the risk of serious long-term consequences.
The employer is required to institute a medical surveillance program for all employees who are or will be exposed to EtO at or above the action level (0.5 ppm) for at least 30 days per year, without regard to respirator use. All examinations and procedures must be performed by or under the supervision of a licensed physician at a reasonable time and place for the employee and at no cost to the employee.
Although broad latitude in prescribing specific tests to be included in the medical surveillance program is extended to the examining physician, OSHA requires inclusion of the following elements in the routine examination:
If requested by the employee, the medical examinations shall include pregnancy testing or laboratory evaluation of fertility as deemed appropriate by the physician.
In certain cases, to provide sound medical advice to the employer and the employee, the physician must evaluate situations not directly related to EtO. For example, employees with skin diseases may be unable to tolerate wearing protective clothing. In addition those with chronic respiratory diseases may not tolerate the wearing of negative pressure (air purifying) respirators. Additional tests and procedures that will help the physician determine which employees are medically unable to wear such respirators should include: An evaluation of cardiovascular function, a baseline chest x-ray to be repeated at five year intervals, and a pulmonary function test to be repeated every three years. The pulmonary function test should include measurement of the employee's forced vital capacity (FVC), forced expiratory volume at one second (FEV1), as well as calculation of the ratios of FEV1 to FVC, and measured FVC and measured FEV1 to expected values corrected for variation due to age, sex, race, and height.
The employer is required to make the prescribed tests available at least annually to employees who are or will be exposed at or above the action level, for 30 or more days per year; more often than specified if recommended by the examining physician; and upon the employee's termination of employment or reassignment to another work area. While little is known about the long term consequences of high short-term exposures, it appears prudent to monitor such affected employees closely in light of existing health data. The employer shall provide physician recommended examinations to any employee exposed to EtO in emergency conditions. Likewise, the employer shall make available medical consultations including physician recommended exams to employees who believe they are suffering signs or symptoms of exposure to EtO.
The employer is required to provide the physician with the following informatin: a copy of this standard and its appendices; a description of the affected employee's duties as they relate to the employee exposure level; and information from the employee's previous medical examinations which is not readily available to the examining physician. Making this information available to the physician will aid in the evaluation of the employee's health in relation to assigned duties and fitness to wear personal protective equipment, when required.
The employer is required to obtain a written opinion from the examining physician containing the results of the medical examinations; the physician's opinion as to whether the employee has any detected medical conditions which would place the employee at increased risk of material impairment of his or her health from exposure to EtO; any recommended restrictions upon the employee's exposure to EtO, or upon the use of protective clothing or equipment such as respirators; and a statement that the employee has been informed by the physician of the results of the medical examination and of any medical conditions which require further explanation or treatment. This written opinion must not reveal specific findings or diagnoses unrelated to occupational exposure to EtO, and a copy of the opinion must be provided to the affected employee.
The purpose in requiring the examining physician to supply the employer with a written opinion is to provide the employer with a medical basis to aid in the determination of initial placement of employees and to assess the employee's ability to use protective clothing and equipment.
Appendix D to § 1910.1047—Sampling and Analytical Methods for Ethylene Oxide (Non-Mandatory)
A number of methods are available for monitoring employee exposures to EtO. Most of these involve the use of charcoal tubes and sampling pumps, followed by analysis of the samples by gas chromatograph. The essential differences between the charcoal tube methods include, among others, the use of different desorbing solvents, the use of different lots of charcoal, and the use of different equipment for analysis of the samples.
Besides charcoal, methods using passive dosimeters, gas sampling bags, impingers, and detector tubes have been utilized for determination of EtO exposure. In addition, there are several commercially available portable gas analyzers and monitoring units.
This appendix contains details for the method which has been tested at the OSHA Analytical Laboratory in Salt Lake City. Inclusion of this method in the appendix does not mean that this method is the only one which will be satisfactory. Copies of descriptions of other methods available are available in the rulemaking record, and may be obtained from the OSHA Docket Office. These include the Union Carbide, Dow Chemical, 3M, and DuPont methods, as well as NIOSH Method S-286. These methods are briefly described at the end of this appendix.
Employers who note problems with sample breakthrough using the OSHA or other charcoal methods should try larger charcoal tubes. Tubes of larger capacity are available. In addition, lower flow rates and shorter sampling times should be beneficial in minimizing breakthrough problems. Whatever method the employer chooses, he must assure himself of the method's accuracy and precision under the unique conditions present in his workplace.
Ethylene Oxide
Method No.: 30.
Matrix: Air.
Target Concentration: 1.0 ppm (1.8 mg/m 3 ).
Procedure: Samples are collected on two charcoal tubes in series and desorbed with 1% CS 2 in benzene. The samples are derivatized with HBr and treated with sodium carbonate. Analysis is done by gas chromatography with an electron capture detector.
Recommended Air Volume and Sampling Rate: 1 liter and 0.05 Lpm.
Detection Limit of the Overall Procedure: 13.3 ppb (0.024 mg/m 3 ) (Based on 1.0 liter air sample).
Reliable Quantitation Limit: 52.2 ppb (0.094 mg/m 3 ) (Based on 1.0 liter air sample).
Standard Error of Estimate: 6.59% (See Backup Section 4.6).
Special Requirements: Samples must be analyzed within 15 days of sampling date.
Status of Method: The sampling and analytical method has been subjected to the established evaluation procedures of the Organic Method Evaluations Branch.
Date: August 1981.
Chemist: Wayne D. Potter.
Organic Solvents Branch, OSHA Analytical Laboratory, Salt Lake City, Utah
1. General Discussion.
1.1 Background.
1.1.1 History of Procedure.
Ethylene oxide samples analyzed at the OSHA Laboratory have normally been collected on activated charcoal and desorbed with carbon disulfide. The analysis is performed with a gas chromatograph equipped with a FID (Flame ionization detector) as described in NIOSH Method S286 (Ref. 5.1). This method is based on a PEL of 50 ppm and has a detection limit of about 1 ppm.
Recent studies have prompted the need for a method to analyze and detect ethylene oxide at very low concentrations.
Several attempts were made to form an ultraviolet (UV) sensitive derivative with ethylene oxide for analysis with HPLC. Among those tested that gave no detectable product were: p-anisidine, methylimidazole, aniline, and 2,3,6-trichlorobenzoic acid. Each was tested with catalysts such as triethylamine, aluminum chloride, methylene chloride and sulfuric acid but no detectable derivative was produced.
The next derivatization attempt was to react ethylene oxide with HBr to form 2-bromoethanol. This reaction was successful. An ECD (electron capture detector) gave a very good response for 2-bromoethanol due to the presence of bromine. The use of carbon disulfide as the desorbing solvent gave too large a response and masked the 2-bromoethanol. Several other solvents were tested for both their response on the ECD and their ability to desorb ethylene oxide from the charcoal. Among those tested were toluene, xylene, ethyl benzene, hexane, cyclohexane and benzene. Benzene was the only solvent tested that gave a suitable response on the ECD and a high desorption. It was found that the desorption efficiency was improved by using 1% CS 2 with the benzene. The carbon disulfide did not significantly improve the recovery with the other solvents. SKC Lot 120 was used in all tests done with activated charcoal.
1.1.2 Physical Properties (Ref. 5.2-5.4).
Synonyms: Oxirane; dimethylene oxide, 1,2-epoxy-ethane; oxane; C 2 H 4 O; ETO;
Molecular Weight: 44.06
Boiling Point: 10.7 °C (51.3°)
Melting Point: −111 °C
Description: Colorless, flammable gas
Vapor Pressure: 1095 mm. at 20 °C
Odor: Ether-like odor
Lower Explosive Limits: 3.0% (by volume)
Flash Point (TOC): Below 0 °F
Molecular Structure: CH 2 —CH 2
1.2 Limit Defining Parameters.
1.2.1 Detection Limit of the Analytical Procedure.
The detection limit of the analytical procedure is 12.0 picograms of ethylene oxide per injection. This is the amount of analyte which will give a peak whose height is five times the height of the baseline noise. (See Backup Data Section 4.1).
1.2.2 Detection Limit of the Overall Procedure.
The detection limit of the overall procedure is 24.0 ng of ethylene oxide per sample.
This is the amount of analyte spiked on the sampling device which allows recovery of an amount of analyte equivalent to the detection limit of the analytical procedure. (See Backup Data Section 4.2).
1.2.3 Reliable Quantitation Limit.
The reliable quantitation limit is 94.0 nanograms of ethylene oxide per sample. This is the smallest amount of analyte which can be quantitated within the requirements of 75% recovery and 95% confidence limits. (See Backup Data Section 4.2).
It must be recognized that the reliable quantitation limit and detection limits reported in the method are based upon optimization of the instrument for the smallest possible amount of analyte. When the target concentration of an analyte is exceptionally higher than these limits, they may not be attainable at the routine operating parameters. In this case, the limits reported on analysis reports will be based on the operating parameters used during the analysis of the samples.
1.2.4 Sensitivity.
The sensitivity of the analytical procedure over a concentration range representing 0.5 to 2 times the target concentration based on the recommended air volume is 34105 area units per µg/mL. The sensitivity is determined by the slope of the calibration curve (See Backup Data Section 4.3).
The sensitivity will vary somewhat with the particular instrument used in the analysis.
1.2.5 Recovery.
The recovery of analyte from the collection medium must be 75% or greater. The average recovery from spiked samples over the range of 0.5 to 2 times the target concentration is 88.0% (See Backup Section 4.4). At lower concentrations the recovery appears to be non-linear.
1.2.6 Precision (Analytical Method Only).
The pooled coefficient of variation obtained from replicate determination of analytical standards at 0.5X, 1X and 2X the target concentration is 0.036 (See Backup Data Section 4.5).
1.2.7 Precision (Overall Procedure).
The overall procedure must provide results at the target concentration that are 25% of better at the 95% confidence level. The precision at the 95% confidence level for the 15 day storage test is plus or minus 12.9% (See Backup Data Section 4.6).
This includes an additional plus or minus 5% for sampling error.
1.3 Advantages.
1.3.1 The sampling procedure is convenient.
1.3.2 The analytical procedure is very sensitive and reproducible.
1.3.3 Reanalysis of samples is possible.
1.3.4 Samples are stable for at least 15 days at room temperature.
1.3.5 Interferences are reduced by the longer GC retention time of the new derivative.
1.4 Disadvantages.
1.4.1 Two tubes in series must be used because of possible breakthrough and migration.
1.4.2 The precision of the sampling rate may be limited by the reproducibility of the pressure drop across the tubes. The pumps are usually calibrated for one tube only.
1.4.3 The use of benzene as the desorption solvent increases the hazards of analysis because of the potential carcinogenic effects of benzene.
1.4.4 After repeated injections there can be a buildup of residue formed on the electron capture detector which decreases sensitivity.
1.4.5 Recovery from the charcoal tubes appears to be nonlinear at low concentrations.
2. Sampling Procedure.
2.1 Apparatus.
2.1.1 A calibrated personal sampling pump whose flow can be determined within plus or minus 5% of the recommended flow.
2.1.2 SKC Lot 120 Charcoal tubes: glass tube with both ends flame sealed, 7 cm long with a 6 mm O.D. and a 4-mm I.D., containing 2 sections of coconut shell charcoal separated by a 2-mm portion of urethane foam. The adsorbing section contains 100 mg of charcoal, the backup section 50 mg. A 3-mm portion of urethane foam is placed between the outlet end of the tube and the backup section. A plug of silylated glass wool is placed in front of the adsorbing section.
2.2 Reagents.
2.2.1 None required.
2.3 Sampling Technique.
2.3.1 Immediately before sampling, break the ends of the charcoal tubes. All tubes must be from the same lot.
2.3.2 Connect two tubes in series to the sampling pump with a short section of flexible tubing. A minimum amount of tubing is used to connect the two sampling tubes together. The tube closer to the pump is used as a backup. This tube should be identified as the backup tube.
2.3.3 The tubes should be placed in a vertical position during sampling to minimize channeling.
2.3.4 Air being sampled should not pass through any hose or tubing before entering the charcoal tubes.
2.3.5 Seal the charcoal tubes with plastic caps immediately after sampling. Also, seal each sample with OSHA seals lengthwise.
2.3.6 With each batch of samples, submit at least one blank tube from the same lot used for samples. This tube should be subjected to exactly the same handling as the samples (break, seal, transport) except that no air is drawn through it.
2.3.7 Transport the samples (and corresponding paperwork) to the lab for analysis.
2.3.8 If bulk samples are submitted for analysis, they shoud be transported in glass containers with Teflon-lined caps. These samples must be mailed separately from the container used for the charcoal tubes.
2.4 Breakthrough.
2.4.1 The breakthrough (5% breakthrough) volume for a 3.0 mg/m ethylene oxide sample stream at approximately 85% relative humidity, 22 °C and 633 mm is 2.6 liters sampled at 0.05 liters per minute. This is equivalent to 7.8 µg of ethylene oxide. Upon saturation of the tube it appeared that the water may be displacing ethylene oxide during sampling.
2.5 Desorption Efficiency.
2.5.1 The desorption efficiency, from liquid injection onto charcoal tubes, averaged 88.0% from 0.5 to 2.0 × the target concentration for a 1.0 liter air sample. At lower ranges it appears that the desorption efficiency is non-linear (See Backup Data Section 4.2).
2.5.2 The desorption efficiency may vary from one laboratory to another and also from one lot of charcoal to another. Thus, it is necessary to determine the desorption efficiency for a particular lot of charcoal.
2.6 Recommended Air Volume and Sampling Rate.
2.6.1 The recommended air volume is 1.0 liter.
2.6.2 The recommended maximum sampling rate is 0.05 Lpm.
2.7 Interferences.
2.7.1 Ethylene glycol and Freon 12 at target concentration levels did not interfere with the collection of ethylene oxide.
2.7.2 Suspected interferences should be listed on the sample data sheets.
2.7.3 The relative humidity may affect the sampling procedure.
2.8 Safety Precautions.
2.8.1 Attach the sampling equipment to the employee so that it does not interfere with work performance.
2.8.2 Wear safety glasses when breaking the ends of the sampling tubes.
2.8.3 If possible, place the sampling tubes in a holder so the sharp end is not exposed while sampling.
3. Analytical Method.
3.1 Apparatus.
3.1.1 Gas chromatograph equipped with a linearized electron capture detector.
3.1.2 GC column capable of separating the derivative of ethylene oxide (2-bromoethanol) from any interferences and the 1% CS 2 in benzene solvent. The column used for validation studies was: 10 ft × 1/8 inch stainless steel 20% SP-2100,.1% Carbowax 1500 on 100/120 Supelcoport.
3.1.3 An electronic integrator or some other suitable method of measuring peak areas.
3.1.4 Two milliliter vials with Teflon-lined caps.
3.1.5 Gas tight syringe—500 µL or other convenient sizes for preparing standards.
3.1.6 Microliter syringes—10 µL or other convenient sizes for diluting standards and 1 µL for sample injections.
3.1.7 Pipets for dispensing the 1% CS 2 in benzene solvent. The Glenco 1 mL dispenser is adequate and convenient.
3.1.8 Volumetric flasks—5 mL and other convenient sizes for preparing standards.
3.1.9 Disposable Pasteur pipets.
3.2 Reagents.
3.2.1 Benzene, reagent grade.
3.2.2 Carbon Disulfide, reagent grade.
3.2.3 Ethylene oxide, 99.7% pure.
3.2.4 Hydrobromic Acid, 48% reagent grade.
3.2.5 Sodium Carbonate, anhydrous, reagent grade.
3.2.6 Desorbing reagent, 99% Benzene/1% CS 2.
3.3 Sample Preparation.
3.3.1 The front and back sections of each sample are transferred to separate 2-mL vials.
3.3.2 Each sample is desorbed with 1.0 mL of desorbing reagent.
3.3.3 The vials are sealed immediately and allowed to desorb for one hour with occasional shaking.
3.3.4 Desorbing reagent is drawn off the charcoal with a disposable pipet and put into clean 2-mL vials.
3.3.5 One drop of HBr is added to each vial. Vials are resealed and HBr is mixed well with the desorbing reagent.
3.3.6 About 0.15 gram of sodium carbonate is carefully added to each vial. Vials are again resealed and mixed well.
3.4 Standard Preparation.
3.4.1 Standards are prepared by injecting the pure ethylene oxide gas into the desorbing reagent.
3.4.2 A range of standards are prepared to make a calibration curve. A concentration of 1.0 µL of ethylene oxide gas per 1 mL desorbing reagent is equivalent to 1.0 ppm air concentration (all gas volumes at 25 °C and 760 mm) for the recommended 1 liter air sample. This amount is uncorrected for desorption efficiency (See Backup Data Section 4.2. for desorption efficiency corrections).
3.4.3 One drop of HBr per mL of standard is added and mixed well.
3.4.4 About 0.15 grams of sodium carbonate is carefully added for each drop of HBr (A small reaction will occur).
3.5 Analysis.
3.5.1 GC Conditions.
Nitrogen flow rate—10mL/min.
Injector Temperature—250 °C
Detector Temperature—300 °C
Column Temperature—100 °C
Injection size—0.8 µL
Elution time—3.9 minutes
3.5.2 Peak areas are measured by an integrator or other suitable means.
3.5.3 The integrator results are in area units and a calibration curve is set up with concentration vs. area units.
3.6 Interferences.
3.6.1 Any compound having the same retention time of 2-bromoethanol is a potential interference. Possible interferences should be listed on the sample data sheets.
3.6.2 GC parameters may be changed to circumvent interferences.
3.6.3 There are usually trace contaminants in benzene. These contaminants, however, posed no problem of interference.
3.6.4 Retention time data on a single column is not considered proof of chemical identity. Samples over the 1.0 ppm target level should be confirmed by GC/Mass Spec or other suitable means.
3.7 Calculations
3.7.1 The concentration in µg/mL for a sample is determined by comparing the area of a particular sample to the calibration curve, which has been prepared from analytical standards.
3.7.2 The amount of analyte in each sample is corrected for desorption efficiency by use of a desorption curve.
3.7.3 Analytical results (A) from the two tubes that compose a particular air sample are added together.
3.7.4 The concentration for a sample is calculated by the following equation:
where:
A = µg/mL
B = desorption volume in milliliters
C = air volume in liters.
3.7.5 To convert mg/m 3 to parts per million (ppm) the following relationship is used:
where:
3
24.45 = molar volume at 25 °C and 760mm Hg
44.05 = molecular weight of ETO.
3.8 Safety Precautions
3.8.1 Ethylene oxide and benzene are potential carcinogens and care must be exercised when working with these compounds.
3.8.2 All work done with the solvents (preparation of standards, desorption of samples, etc.) should be done in a hood.
3.8.3 Avoid any skin contact with all of the solvents.
3.8.4 Wear safety glasses at all times.
3.8.5 Avoid skin contact with HBr because it is highly toxic and a strong irritant to eyes and skin.
4. Backup Data.
4.1 Detection Limit Data.
The detection limit was determined by injecting 0.8 µL of a 0.015 µg/mL standard of ethylene oxide into 1% CS 2 in benzene. The detection limit of the analytical procedure is taken to be 1.20 × 10 −5 µg per injection. This is equivalent to 8.3 ppb (0.015 mg/m 3 ) for the recommended air volume.
4.2 Desorption Efficiency.
Ethylene oxide was spiked onto charcoal tubes and the following recovery data was obtained.
| Amount spiked (µg) | Amount recovered (µg) | Percent recovery |
|---|---|---|
| 4.5 | 4.32 | 96.0 |
| 3.0 | 2.61 | 87.0 |
| 2.25 | 2.025 | 90.0 |
| 1.5 | 1.365 | 91.0 |
| 1.5 | 1.38 | 92.0 |
| .75 | .6525 | 87.0 |
| .375 | .315 | 84.0 |
| .375 | .312 | 83.2 |
| .1875 | .151 | 80.5 |
| .094 | .070 | 74.5 |
At lower amounts the recovery appears to be non-linear.
4.3 Sensitivity Data.
The following data was used to determine the calibration curve.
| Injection | 0.5 × .75 µg/mL | 1 × 1.5 µg/mL | 2 × 3.0 µg/mL |
|---|---|---|---|
| 1 | 30904 | 59567 | 111778 |
| 2 | 30987 | 62914 | 106016 |
| 3 | 32555 | 58578 | 106122 |
| 4 | 32242 | 57173 | 109716 |
| X | 31672 | 59558 | 108408 |
| Slope = 34.105. |
4.4 Recovery.
The recovery was determined by spiking ethylene oxide onto lot 120 charcoal tubes and desorbing with 1% CS 2 in Benzene. Recoveries were done at 0.5, 1.0, and 2.0× the target concentration (1 ppm) for the recommended air volume.
| Sample | 0.5x | 1.0x | 2.0x |
|---|---|---|---|
| 1 | 88.7 | 95.0 | 91.7 |
| 2 | 83.8 | 95.0 | 87.3 |
| 3 | 84.2 | 91.0 | 86.0 |
| 4 | 88.0 | 91.0 | 83.0 |
| 5 | 88.0 | 86.0 | 85.0 |
| X | 86.5 | 90.5 | 87.0 |
| Weighted Average = 88.2. |
4.5 Precision of the Analytical Procedure.
The following data was used to determine the precision of the analytical method:
| Concentration | 0.5 × .75 µg/mL | 1 × 1.5 µg/mL | 2 × 3.0 µg/mL |
|---|---|---|---|
| Injection | .7421 | 1.4899 | 3.1184 |
| .7441 | 1.5826 | 3.0447 | |
| .7831 | 1.4628 | 2.9149 | |
| .7753 | 1.4244 | 2.9185 | |
| Average | .7612 | 1.4899 | 2.9991 |
| Standard Deviation | .0211 | .0674 | .0998 |
| CV | .0277 | .0452 | .0333 |
CV + 0.036
4.6 Storage Data.
Samples were generated at 1.5 mg/m 3 ethylene oxide at 85% relative humidity, 22 °C and 633 mm. All samples were taken for 20 minutes at 0.05 Lpm. Six samples were analyzed as soon as possible and fifteen samples were stored at refrigerated temperature (5 °C) and fifteen samples were stored at ambient temperature (23 °C). These stored samples were analyzed over a period of nineteen days.
| Day analyzed | Refrigerated | Ambient |
|---|---|---|
| 1 | 87.0 | 87.0 |
| 1 | 93.0 | 93.0 |
| 1 | 94.0 | 94.0 |
| 1 | 92.0 | 92.0 |
| 4 | 92.0 | 91.0 |
| 4 | 93.0 | 88.0 |
| 4 | 91.0 | 89.0 |
| 6 | 92.0 | |
| 6 | 92.0 | |
| 8 | 92.0 | |
| 8 | 86.0 | |
| 10 | 91.7 | |
| 10 | 95.5 | |
| 10 | 95.7 | |
| 11 | 90.0 | |
| 11 | 82.0 | |
| 13 | 78.0 | |
| 13 | 81.4 | |
| 13 | 82.4 | |
| 14 | 78.5 | |
| 14 | 72.1 | |
| 18 | 66.0 | |
| 18 | 68.0 | |
| 19 | 64.0 | |
| 19 | 77.0 |
4.7 Breakthrough Data.
Breakthrough studies were done at 2 ppm (3.6 mg/m 3 ) at approximately 85% relative humidity at 22 °C (ambient temperature). Two charcoal tubes were used in series. The backup tube was changed every 10 minutes and analyzed for breakthrough. The flow rate was 0.050 Lpm.
| Tube No. | Time (minutes) | Percent breakthrough |
|---|---|---|
| 1 | 10 | ( 1 ) |
| 2 | 20 | ( 1 ) |
| 3 | 30 | ( 1 ) |
| 4 | 40 | 1.23 |
| 5 | 50 | 3.46 |
| 6 | 60 | 18.71 |
| 7 | 70 | 39.2 |
| 8 | 80 | 53.3 |
| 9 | 90 | 72.0 |
| 10 | 100 | 96.0 |
| 11 | 110 | 113.0 |
| 12 | 120 | 133.9 |
| 1 None. |
The 5% breakthrough volume was reached when 2.6 liters of test atmosphere were drawn through the charcoal tubes.
5. References.
5.1 “NIOSH Manual of Analytical Methods,” 2nd ed. NIOSH: Cincinnati, 1977; Method S286.
5.2 “IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Man,” International Agency for Research on Cancer: Lyon, 1976; Vol. II, p. 157.
5.3 Sax., N.I. “Dangerous Properties of Industrial Materials,” 4th ed.; Van Nostrand Reinhold Company. New York, 1975; p. 741.
5.4 “The Condensed Chemical Dictionary”, 9th ed.; Hawley, G.G., ed.; Van Nostrand Reinhold Company, New York, 1977; p. 361.
Summary of Other Sampling Procedures
OSHA believes that served other types of monitoring equipment and techniques exist for monitoring time-weighted averages. Considerable research and method development is currently being performed, which will lead to improvements and a wider variety of monitoring techniques. A combination of monitoring procedures can be used. There probably is no one best method for monitoring personal exposure to ethylene oxide in all cases. There are advantages, disadvantages, and limitations to each method. The method of choice will depend on the need and requirements. Some commonly used methods include the use of charcoal tubes, passive dosimeters, Tedler gas sampling bags, detector tubes, photoionization detection units, infrared detection units and gas chromatographs. A number of these methods are described below.
A. Charcoal Tube Sampling Procedures
Qazi-Ketcham method (Ex. 11-133)—This method consists of collecting EtO on Columbia JXC activated carbon, desorbing the EtO with carbon disulfide and analyzing by gas chromatography with flame ionization detection. Union Carbide has recently updated and revalidated this monitoring procedures. This method is capable of determining both eight-hour time-weighted average exposures and short-term exposures. The method was validated to 0.5 ppm. Like other charcoal collecting procedures, the method requires considerable analytical expertise.
ASTM-proposed method —The Ethylene Oxide Industry Council (EOIC) has contracted with Clayton Environmental Consultants, Inc. to conduct a collaborative study for the proposed method. The ASTM-Proposed method is similar to the method published by Qazi and Ketcham is the November 1977 American Industrial Hygiene Association Journal, and to the method of Pilney and Coyne, presented at the 1979 American Industrial Hygiene Conference. After the air to be sampled is drawn through an activated charcoal tube, the ethylene oxide is desorbed from the tube using carbon disulfide and is quantitated by gas chromatography utilizing a flame ionization detector. The ASTM-proposed method specifies a large two-section charcoal tube, shipment in dry ice, storage at less
than −5 °C, and analysis within three weeks to prevent migration and sample loss. Two types of charcoal tubes are being tested—Pittsburgh Coconut-Based (PCB) and Columbia JXC charcoal. This collaborative study will give an indication of the inter- and intralaboratory precision and accuracy of the ASTM-proposed method. Several laboratories have considerable expertise using the Qazi-Ketcham and Dow methods.
B. Passive Monitors—Ethylene oxide diffuses into the monitor and is collected in the sampling media. The DuPont Pro-Tek badge collects EtO in an absorbing solution, which is analyzed colorimetrically to determine the amount of EtO present. The 3M 350 badge collects the EtO on chemically treated charcoal. Other passive monitors are currently being developed and tested. Both 3M and DuPont have submitted data indicating their dosimeters meet the precision and accuracy requirements of the proposed ethylene oxide standard. Both presented laboratory validation data to 0.2 ppm (Exs. 11-65, 4-20, 108, 109, 130).
C. Tedlar Gas Sampling Bags-Samples are collected by drawing a known volume of air into a Tedlar gas sampling bag. The ethylene oxide concentration is often determined on-site using a portable gas chromatograph or portable infrared spectometer.
D. Detector tubes—A known volume of air is drawn through a detector tube using a small hand pump. The concentration of EtO is related to the length of stain developed in the tube. Detector tubes are economical, easy to use, and give an immediate readout. Unfortunately, partly because they are nonspecific, their accuracy is often questionable. Since the sample is taken over a short period of time, they may be useful for determining the source of leaks.
E. Direct Reading Instruments—There are numerous types of direct reading instruments, each having its own strengths and weaknesses (Exs. 135B, 135C, 107, 11-78, 11-153). Many are relatively new, offering greater sensitivity and specificity. Popular ethylene oxide direct reading instruments include infrared detection units, photoionization detection units, and gas chromatographs.
Portable infrared analyzers provide an immediate, continuous indication of a concentration value; making them particularly useful for locating high concentration pockets, in leak detection and in ambient air monitoring. In infrared detection units, the amount of infrared light absorbed by the gas being analyzed at selected infrared wavelengths is related to the concentration of a particular component. Various models have either fixed or variable infrared filters, differing cell pathlengths, and microcomputer controls for greater sensitivity, automation, and interference elimination.
A fairly recent detection system is photoionization detection. The molecules are ionized by high energy ultraviolet light. The resulting current is measured. Since different substances have different ionization potentials, other organic compounds may be ionized. The lower the lamp energy, the better the selectivity. As a continuous monitor, photoionization detection can be useful for locating high concentration pockets, in leak detection, and continuous ambient air monitoring. Both portable and stationary gas chromatographs are available with various types of detectors, including photoionization detectors. A gas chromatograph with a photoionization detector retains the photionization sensitivity, but minimizes or eliminates interferences. For several GC/PID units, the sensitivity is in the 0.1-0.2 ppm EtO range. The GC/PID with microprocessors can sample up to 20 sample points sequentially, calculate and record data, and activate alarms or ventilation systems. Many are quite flexible and can be configured to meet the specific analysis needs for the workplace.
DuPont presented their laboratory validation data of the accuracy of the Qazi-Ketcham charcoal tube, the PCB charcoal tube, Miran 103 IR analyzer, 3M #3550 monitor and the Du Pont C-70 badge. Quoting Elbert V. Kring:
We also believe that OSHA's proposed accuracy in this standard is appropriate. At plus or minus 25 percent at one part per million, and plus or minus 35 percent below that. And, our data indicates there's only one monitoring method, right now, that we've tested thoroughly, that meets that accuracy requirements. That is the Du Pont Pro-Tek badge* * *. We also believe that this kind of data should be confirmed by another independent laboratory, using the same type dynamic chamber testing (Tr. 1470)
Additional data by an independent laboratory following their exact protocol was not submitted. However, information was submitted on comparisons and precision and accuracy of those monitoring procedures which indicate far better precision and accuracy of those monitoring procedures than that obtained by Du Pont (Ex. 4-20, 130, 11-68, 11-133, 130, 135A).
The accuracy of any method depends to a large degree upon the skills and experience of those who not only collect the samples but also those who analyze the samples. Even for methods that are collaboratively tested, some laboratories are closer to the true values than others. Some laboratories may meet the precision and accuracy requirements of the method; others may consistently far exceed them for the same method.
[49 FR 25796, June 22, 1984, as amended at 50 FR 9801, Mar. 12, 1985; 50 FR 41494, Oct. 11, 1985; 51 FR 25053, July 10, 1986; 53 FR 11436, 11437, Apr. 6, 1988; 53 FR 27960, July 26, 1988; 54 FR 24334, June 7, 1989; 61 FR 5508, Feb. 13, 1996; 63 FR 1292, Jan. 8, 1998; 67 FR 67965, Nov. 7, 2002; 70 FR 1143, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50190, Aug. 24, 2006; 73 FR 75586, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR 17783, Mar. 26, 2012; 84 FR 21490, May 14, 2019]
This standard applies to all occupational exposures to formaldehyde, i.e. from formaldehyde gas, its solutions, and materials that release formaldehyde.
For purposes of this standard, the following definitions shall apply:
Action level means a concentration of 0.5 part formaldehyde per million parts of air (0.5 ppm) calculated as an eight (8)-hour time-weighted average (TWA) concentration.
Assistant Secretary means the Assistant Secretary of Labor for the Occupational Safety and Health Administration, U.S. Department of Labor, or designee.
Authorized person means any person required by work duties to be present in regulated areas, or authorized to do so by the employer, by this section, or by the OSH Act of 1970.
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency is any occurrence, such as but not limited to equipment failure, rupture of containers, or failure of control equipment that results in an uncontrolled release of a significant amount of formaldehyde.
Employee exposure means the exposure to airborne formaldehyde which would occur without corrections for protection provided by any respirator that is in use.
Formaldehyde means the chemical substance, HCHO, Chemical Abstracts Service Registry No. 50-00-0.
The employer shall assure that no employee is exposed to an airborne concentration of formaldehyde which exceeds 0.75 parts formaldehyde per million parts of air (0.75 ppm) as an 8-hour TWA.
The employer shall assure that no employee is exposed to an airborne concentration of formaldehyde which exceeds two parts formaldehyde per million parts of air (2 ppm) as a 15-minute STEL.
Where the employer documents, using objective data, that the presence of formaldehyde or formaldehyde-releasing products in the workplace cannot result in airborne concentrations of formaldehyde that would cause any employee to be exposed at or above the action level or the STEL under foreseeable conditions of use, the employer will not be required to measure employee exposure to formaldehyde.
The employer shall identify all employees who may be exposed at or above the action level or at or above the STEL and accurately determine the exposure of each employee so identified.
The employer may discontinue periodic monitoring for employees if results from two consecutive sampling periods taken at least 7 days apart show that employee exposure is below the action level and the STEL. The results must be statistically representative and consistent with the employer's knowledge of the job and work operation.
Monitoring shall be accurate, at the 95 percent confidence level, to within plus or minus 25 percent for airborne concentrations of formaldehyde at the TWA and the STEL and to within plus or minus 35 percent for airborne concentrations of formaldehyde at the action level.
The employer must, within 15 working days after the receipt of the results of any monitoring performed under this section, notify each affected employee of these results either individually in writing or by posting the results in an appropriate location that is accessible to employees. If employee exposure is above the PEL, affected employees shall be provided with a description of the corrective actions being taken by the employer to decrease exposure.
DANGER
FORMALDEHYDE
MAY CAUSE CANCER
CAUSES SKIN, EYE, AND RESPIRATORY IRRITATION
AUTHORIZED PERSONNEL ONLY
DANGER
FORMALDEHYDE
IRRITANT AND POTENTIAL CANCER HAZARD
AUTHORIZED PERSONNEL ONLY
The employer shall institute engineering and work practice controls to reduce and maintain employee exposures to formaldehyde at or below the TWA and the STEL.
Whenever the employer has established that feasible engineering and work practice controls cannot reduce employee exposure to or below either of the PELs, the employer shall apply these controls to reduce employee exposures to the extent feasible and shall supplement them with respirators which satisfy this standard.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Employers shall comply with the provisions of 29 CFR 1910.132 and 29 CFR 1910.133. When protective equipment or clothing is provided under these provisions, the employer shall provide these protective devices at no cost to the employee and assure that the employee wears them.
The employer shall select protective clothing and equipment based upon the form of formaldehyde to be encountered, the conditions of use, and the hazard to be prevented.
Storage areas for contaminated clothing and equipment shall have signs bearing the following legend:
DANGER
FORMALDEHYDE-CONTAMINATED [CLOTHING] EQUIPMENT
MAY CAUSE CANCER
CAUSES SKIN, EYE AND RESPIRATORY IRRITATION
DO NOT BREATHE VAPOR
DO NOT GET ON SKIN
The employer shall ensure containers for contaminated clothing and equipment are labeled consistent with the Hazard Communication Standard, § 1910.1200, and shall, as a minimum, include the following:
DANGER
FORMALDEHYDE-CONTAMINATED [CLOTHING] EQUIPMENT
MAY CAUSE CANCER
CAUSES SKIN, EYE, AND RESPIRATORY IRRITATION
DO NOT BREATHE VAPOR
DO NOT GET ON SKIN
DANGER
FORMALDEHYDE-CONTAMINATED [CLOTHING] EQUIPMENT
AVOID INHALATION AND SKIN CONTACT
DANGER
FORMALDEHYDE-CONTAMINATED [CLOTHING] EQUIPMENT
AVOID INHALATION AND SKIN CONTACT
For operations involving formaldehyde liquids or gas, the employer shall conduct a program to detect leaks and spills, including regular visual inspections.
For each workplace where there is the possibility of an emergency involving formaldehyde, the employer shall assure appropriate procedures are adopted to minimize injury and loss of life. Appropriate procedures shall be implemented in the event of an emergency.
All medical procedures, including administration of medical disease questionnaires, shall be performed by or under the supervision of a licensed physician and shall be provided without cost to the employee, without loss of pay, and at a reasonable time and place.
The employer shall make the following medical surveillance available to employees prior to assignment to a job where formaldehyde exposure is at or above the action level or above the STEL and annually thereafter. The employer shall also make the following medical surveillance available promptly upon determining that an employee is experiencing signs and symptoms indicative of possible overexposure to formaldehyde.
Medical examinations shall be given to any employee who the physician feels, based on information in the medical disease questionnaire, may be at increased risk from exposure to formaldehyde and at the time of initial assignment and at least annually thereafter to all employees required to wear a respirator to reduce exposure to formaldehyde. The medical examination shall include:
The employer shall make medical examinations available as soon as possible to all employees who have been exposed to formaldehyde in an emergency.
The employer shall provide the following information to the examining physician:
The employer shall assure that all employees who are assigned to workplaces where there is exposure to formaldehyde participate in a training program, except that where the employer can show, using objective data, that employees are not exposed to formaldehyde at or above 0.1 ppm, the employer is not required to provide training.
Employers shall provide such information and training to employees at the time of initial assignment, and whenever a new exposure to formaldehyde is introduced into the work area. The training shall be repeated at least annually.
The training program shall be conducted in a manner which the employee is able to understand and shall include:
The employer shall establish and maintain an accurate record of all measurements taken to monitor employee exposure to formaldehyde. This record shall include:
Where the employer has determined that no monitoring is required under this standard, the employer shall maintain a record of the objective data relied upon to support the determination that no employee is exposed to formaldehyde at or above the action level.
The employer shall establish and maintain an accurate record for each employee subject to medical surveillance under this standard. This record shall include:
The employer shall retain records required by this standard for at least the following periods:
Appendix A to § 1910.1048—Substance Technical Guidelines for Formalin
The following Substance Technical Guideline for Formalin provides information on uninhibited formalin solution (37% formaldehyde, no methanol stabilizer). It is designed to inform employees at the production level of their rights and duties under the formaldehyde standard whether their job title defines them as workers or supervisors. Much of the information provided is general; however, some information is specific for formalin. When employee exposure to formaldehyde is from resins capable of releasing formaldehyde, the resin itself and other impurities or decomposition products may also be toxic, and employers should include this information as well when informing employees of the hazards associated with the materials they handle. The precise hazards associated with exposure to formaldehyde depend both on the form (solid, liquid, or gas) of the material and the concentration of formaldehyde present. For example, 37-50 percent solutions of formaldehyde present a much greater hazard to the skin and eyes from spills or splashes than solutions containing less than 1 percent formaldehyde. Individual Substance Technical Guidelines used by the employer for training employees should be modified to properly give information on the material actually being used.
Substance Identification
Chemical Name:
Chemical Family:
Chemical Formula:
Molecular Weight:
Chemical Abstracts Service Number (CAS Number):
Synonyms: Formalin; Formic Aldehyde; Paraform; Formol; Formalin (Methanol-free); Fyde; Formalith; Methanal; Methyl Aldehyde; Methylene Glycol; Methylene Oxide; Tetraoxymethalene; Oxomethane; Oxymethylene
Components and Contaminants
Percent:
Percent:
Other Contaminants:
Exposure Limits:
OSHA TWA—0.75 ppm
OSHA STEL—2 ppm
Physical Data
Description:
Boiling point:
Specific Gravity:
2
pH:
Solubility in Water:
Solvent Solubility:
Vapor Density:
Odor Threshold:
Fire and Explosion Hazard
Moderate fire and explosion hazard when exposed to heat or flame.
The flash point of 37% formaldehyde solutions is above normal room temperature, but the explosion range is very wide, from 7 to 73% by volume in air.
Reaction of formaldehyde with nitrogen dioxide, nitromethane, perchloric acid and aniline, or peroxyformic acid yields explosive compounds.
Flash Point:
Lower Explosion Limit:
Upper Explosion Limit:
Autoignition Temperature:
Flammability (OSHA): Category 4 flammable liquid
Extinguishing Media: Use dry chemical, “alcohol foam”, carbon dioxide, or water in flooding amounts as fog. Solid streams may not be effective. Cool fire-exposed containers with water from side until well after fire is out.
Use of water spray to flush spills can also dilute the spill to produce nonflammable mixtures. Water runoff, however, should be contained for treatment.
National Fire Protection Association Section 325M Designation:
Health: 2—Materials hazardous to health, but areas may be entered with full-faced mask self-contained breathing apparatus which provides eye protection.
Flammability: 2—Materials which must be moderately heated before ignition will occur. Water spray may be used to extinguish the fire because the material can be cooled below its flash point.
Reactivity: D—Materials which (in themselves) are normally stable even under fire exposure conditions and which are not reactive with water. Normal fire fighting procedures may be used.
Reactivity
Stability: Formaldehyde solutions may self-polymerize to form paraformaldehyde which precipitates.
Incompatibility (Materials to Avoid): Strong oxidizing agents, caustics, strong alkalies, isocyanates, anhydrides, oxides, and inorganic acids. Formaldehyde reacts with hydrochloric acid to form the potent carcinogen, bis-chloromethyl ether. Formaldehyde reacts with nitrogen dioxide, nitromethane, perchloric acid and aniline, or peroxyformic acid to yield explosive compounds. A violent reaction occurs when formaldehyde is mixed with strong oxidizers.
Hazardous Combustion or Decomposition Products: Oxygen from the air can oxidize formaldehyde to formic acid, especially when heated. Formic acid is corrosive.
Health Hazard Data
Acute Effects of Exposure
Ingestion (Swallowing): Liquids containing 10 to 40% formaldehyde cause severe irritation and inflammation of the mouth, throat, and stomach. Severe stomach pains will follow ingestion with possible loss of consciousness and death. Ingestion of dilute formaldehyde solutions (0.03-0.04%) may cause discomfort in the stomach and pharynx.
Inhalation (Breathing): Formaldehyde is highly irritating to the upper respiratory tract and eyes. Concentrations of 0.5 to 2.0 ppm may irritate the eyes, nose, and throat of some individuals. Concentrations of 3 to 5 ppm also cause tearing of the eyes and are intolerable to some persons. Concentrations of 10 to 20 ppm cause difficulty in breathing, burning of the nose and throat, cough, and heavy tearing of the eyes, and 25 to 30 ppm causes severe respiratory tract injury leading to pulmonary edema and pneumonitis. A concentration of 100 ppm is immediately dangerous to life and health. Deaths from accidental exposure to high concentrations of formaldehyde have been reported.
Skin (Dermal): Formalin is a severe skin irritant and a sensitizer. Contact with formalin causes white discoloration, smarting, drying, cracking, and scaling. Prolonged and repeated contact can cause numbness and a hardening or tanning of the skin. Previously exposed persons may react to future exposure with an allergic eczematous dermatitis or hives.
Eye Contact: Formaldehyde solutions splashed in the eye can cause injuries ranging from transient discomfort to severe, permanent corneal clouding and loss of vision. The severity of the effect depends on the concentration of formaldehyde in the solution and whether or not the eyes are flushed with water immediately after the accident.
Acute Animal Toxicity:
Oral,
Oral,
Inhalation,
Inhalation,
Inhalation,
Chronic Effects of Exposure
Carcinogenicity: Formaldehyde has the potential to cause cancer in humans. Repeated and prolonged exposure increases the risk. Various animal experiments have conclusively shown formaldehyde to be a carcinogen in rats. In humans, formaldehyde exposure has been associated with cancers of the lung, nasopharynx and oropharynx, and nasal passages.
Mutagenicity: Formaldehyde is genotoxic in several in vitro test systems showing properties of both an initiator and a promoter.
Toxicity: Prolonged or repeated exposure to formaldehyde may result in respiratory impairment. Rats exposed to formaldehyde at 2 ppm developed benign nasal tumors and changes of the cell structure in the nose as well as inflamed mucous membranes of the nose. Structural changes in the epithelial cells in the human nose have also been observed. Some persons have developed asthma or bronchitis following exposure to formaldehyde, most often as the result of an accidental spill involving a single exposure to a high concentration of formaldehyde.
Emergency and First Aid Procedures
Ingestion (Swallowing): If the victim is conscious, dilute, inactivate, or absorb the ingested formaldehyde by giving milk, activated charcoal, or water. Any organic material will inactivate formaldehyde. Keep affected person warm and at rest. Get medical attention immediately. If vomiting occurs, keep head lower than hips.
Inhalation (Breathing): Remove the victim from the exposure area to fresh air immediately. Where the formaldehyde concentration may be very high, each rescuer must put on a self-contained breathing apparatus before attempting to remove the victim, and medical personnel should be informed of the formaldehyde exposure immediately. If breathing has stopped, give artificial respiration. Keep the affected person warm and at rest. Qualified first-aid or medical personnel should administer oxygen, if available, and maintain the patient's airways and blood pressure until the victim can be transported to a medical facility. If exposure results in a highly irritated upper respiratory tract and coughing continues for more than 10 minutes, the worker should be hospitalized for observation and treatment.
Skin Contact: Remove contaminated clothing (including shoes) immediately. Wash the affected area of your body with soap or mild detergent and large amounts of water until no evidence of the chemical remains (at least 15 to 20 minutes). If there are chemical burns, get first aid to cover the area with sterile, dry dressing, and bandages. Get medical attention if you experience appreciable eye or respiratory irritation.
Eye Contact: Wash the eyes immediately with large amounts of water occasionally lifting lower and upper lids, until no evidence of chemical remains (at least 15 to 20 minutes). In case of burns, apply sterile bandages loosely without medication. Get medical attention immediately. If you have experienced appreciable eye irritation from a splash or excessive exposure, you should be referred promptly to an opthamologist for evaluation.
Emergency Procedures
Emergencies: If you work in an area where a large amount of formaldehyde could be released in an accident or from equipment failure, your employer must develop procedures to be followed in event of an emergency. You should be trained in your specific duties in the event of an emergency, and it is important that you clearly understand these duties. Emergency equipment must be accessible and you should be trained to use any equipment that you might need. Formaldehyde contaminated equipment must be cleaned before reuse.
If a spill of appreciable quantity occurs, leave the area quickly unless you have specific emergency duties. Do not touch spilled material. Designated persons may stop the leak and shut off ignition sources if these procedures can be done without risk. Designated persons should isolate the hazard area and deny entry except for necessary people protected by suitable protective clothing and respirators adequate for the exposure. Use water spray to reduce vapors. Do not smoke, and prohibit all flames or flares in the hazard area.
Special Firefighting Procedures: Learn procedures and responsibilities in the event of a fire in your workplace. Become familiar with the appropriate equipment and supplies and their location. In firefighting, withdraw immediately in case of rising sound from venting safety device or any discoloration of storage tank due to fire.
Spill, Leak, and Disposal Procedures
Occupational Spill: For small containers, place the leaking container in a well ventilated area. Take up small spills with absorbent material and place the waste into properly labeled containers for later disposal. For larger spills, dike the spill to minimize contamination and facilitate salvage or disposal. You may be able to neutralize the spill with sodium hydroxide or sodium sulfite. Your employer must comply with EPA rules regarding the clean-up of toxic waste and notify state and local authorities, if required. If the spill is greater than 1,000 lb/day, it is reportable under EPA's Superfund legislation.
Waste Disposal: Your employer must dispose of waste containing formaldehyde in accordance with applicable local, state, and Federal law and in a manner that minimizes exposure of employees at the site and of the clean-up crew.
Monitoring and Measurement Procedures
Monitoring Requirements: If your exposure to formaldehyde exceeds the 0.5 ppm action level or the 2 ppm STEL, your employer must monitor your exposure. Your employer need not measure every exposure if a “high exposure” employee can be identified. This person usually spends the greatest amount of time nearest the process equipment. If you are a “representative employee”, you will be asked to wear a sampling device to collect formaldehyde. This device may be a passive badge, a sorbent tube attached to a pump, or an impinger containing liquid. You should perform your work as usual, but inform the person who is conducting the monitoring of any difficulties you are having wearing the device.
Evaluation of 8-hour Exposure: Measurements taken for the purpose of determining time-weighted average (TWA) exposures are best taken with samples covering the full shift. Samples collected must be taken from the employee's breathing zone air.
Short-term Exposure Evaluation: If there are tasks that involve brief but intense exposure to formaldehyde, employee exposure must be measured to assure compliance with the STEL. Sample collections are for brief periods, only 15 minutes, but several samples may be needed to identify the peak exposure.
Monitoring Techniques: OSHA's only requirement for selecting a method for sampling and analysis is that the methods used accurately evaluate the concentration of formaldehyde in employees' breathing zones. Sampling and analysis may be performed by collection of formaldehyde on liquid or solid sorbents with subsequent chemical analysis. Sampling and analysis may also be performed by passive diffusion monitors and short-term exposure may be measured by instruments such as real-time continuous monitoring systems and portable direct reading instruments.
Notification of Results: Your employer must inform you of the results of exposure monitoring representative of your job. You may be informed in writing, but posting the results where you have ready access to them constitutes compliance with the standard.
Protective Equipment and Clothing
[Material impervious to formaldehyde is needed if the employee handles formaldehyde solutions of 1% or more. Other employees may also require protective clothing or equipment to prevent dermatitis.]
Respiratory Protection: Use NIOSH-approved full facepiece negative pressure respirators equipped with approved cartridges or canisters within the use limitations of these devices. (Present restrictions on cartridges and canisters do not permit them to be used for a full workshift.) In all other situations, use positive pressure respirators such as the positive-pressure air purifying respirator or the self-contained breathing apparatus (SCBA). If you use a negative pressure respirator, your employer must provide you with fit testing of the respirator at least once a year.
Protective Gloves: Wear protective (impervious) gloves provided by your employer, at no cost, to prevent contact with formalin. Your employer should select these gloves based on the results of permeation testing and in accordance with the ACGIH Guidelines for Selection of Chemical Protective Clothing.
Eye Protection: If you might be splashed in the eyes with formalin, it is essential that you wear goggles or some other type of complete protection for the eye. You may also need a face shield if your face is likely to be splashed with formalin, but you must not substitute face shields for eye protection. (This section pertains to formaldehyde solutions of 1% or more.)
Other Protective Equipment: You must wear protective (impervious) clothing and equipment provided by your employer at no cost to prevent repeated or prolonged contact with formaldehyde liquids. If you are required to change into whole-body chemical protective clothing, your employer must provide a change room for your privacy and for storage of your normal clothing.
If you are splashed with formaldehyde, use the emergency showers and eyewash fountains provided by your employer immediately to prevent serious injury. Report the incident to your supervisor and obtain necessary medical support.
Entry Into an IDLH Atmosphere
Enter areas where the formaldehyde concentration might be 100 ppm or more only with complete body protection including a self-contained breathing apparatus with a full facepiece operated in a positive pressure mode or a supplied air respirator with full facepiece and operated in a positive pressure mode. This equipment is essential to protect your life and health under such extreme conditions.
Engineering Controls
Ventilation is the most widely applied engineering control method for reducing the concentration of airborne substances in the breathing zones of workers. There are two distinct types of ventilation.
Local Exhaust: Local exhaust ventilation is designed to capture airborne contaminants as near to the point of generation as possible. To protect you, the direction of contaminant flow must always be toward the local exhaust system inlet and away from you.
General (Mechanical): General dilution ventilation involves continuous introduction of fresh air into the workroom to mix with the contaminated air and lower your breathing zone concentration of formaldehyde. Effectiveness depends on the number of air changes per hour. Where devices emitting formaldehyde are spread out over a large area, general dilution ventilation may be the only practical method of control.
Work Practices: Work practices and administrative procedures are an important part of a control system. If you are asked to perform a task in a certain manner to limit your exposure to formaldehyde, it is extremely important that you follow these procedures.
Medical Surveillance
Medical surveillance helps to protect employees' health. You are encouraged strongly to participate in the medical surveillance program.
Your employer must make a medical surveillance program available at no expense to you and at a reasonable time and place if you are exposed to formaldehyde at concentrations above 0.5 ppm as an 8-hour average or 2 ppm over any 15-minute period. You will be offered medical surveillance at the time of your initial assignment and once a year afterward as long as your exposure is at least 0.5 ppm (TWA) or 2 ppm (STEL). Even if your exposure is below these levels, you should inform your employer if you have signs and symptoms that you suspect, through your training, are related to your formaldehyde exposure because you may need medical surveillance to determine if your health is being impaired by your exposure.
The surveillance plan includes:
If you are required to wear a respirator, your employer must offer you a physical examination and a pulmonary function test every year.
The physician must collect all information needed to determine if you are at increased risk from your exposure to formaldehyde. At the physician's discretion, the medical examination may include other tests, such as a chest x-ray, to make this determination.
After a medical examination the physician will provide your employer with a written opinion which includes any special protective measures recommended and any restrictions on your exposure. The physician must inform you of any medical conditions you have which would be aggravated by exposure to formaldehyde.
All records from your medical examinations, including disease surveys, must be retained at your employer's expense.
Emergencies
If you are exposed to formaldehyde in an emergency and develop signs or symptoms associated with acute toxicity from formaldehyde exposure, your employer must provide you with a medical examination as soon as possible. This medical examination will include all steps necessary to stabilize your health. You may be kept in the hospital for observation if your symptoms are severe to ensure that any delayed effects are recognized and treated.
Appendix B to § 1910.1048—Sampling Strategy and Analytical Methods for Formaldehyde
To protect the health of employees, exposure measurements must be unbiased and representative of employee exposure. The proper measurement of employee exposure requires more than a token commitment on the part of the employer. OSHA's mandatory requirements establish a baseline; under the best of circumstances all questions regarding employee exposure will be answered. Many employers, however, will wish to conduct more extensive monitoring before undertaking expensive commitments, such as engineering controls, to assure that the modifications are truly necessary. The following sampling strategy, which was developed at NIOSH by Nelson A. Leidel, Kenneth A. Busch, and Jeremiah R. Lynch and described in NIOSH publication No. 77-173 (Occupational Exposure Sampling Strategy Manual) will assist the employer in developing a strategy for determining the exposure of his or her employees.
There is no one correct way to determine employee exposure. Obviously, measuring the exposure of every employee exposed to formaldehyde will provide the most information on any given day. Where few employees are exposed, this may be a practical solution. For most employers, however, use of the following strategy will give just as much information at less cost.
Exposure data collected on a single day will not automatically guarantee the employer that his or her workplace is always in compliance with the formaldehyde standard. This does not imply, however, that it is impossible for an employer to be sure that his or her worksite is in compliance with the standard. Indeed, a properly designed sampling strategy showing that all employees are exposed below the PELs, at least with a 95 percent certainty, is compelling evidence that the exposure limits are being achieved provided that measurements are conducted using valid sampling strategy and approved analytical methods.
There are two PELs, the TWA concentration and the STEL. Most employers will find that one of these two limits is more critical in the control of their operations, and OSHA expects that the employer will concentrate monitoring efforts on the critical component. If the more difficult exposure is controlled, this information, along with calculations to support the assumptions, should be adequate to show that the other exposure limit is also being achieved.
Sampling Strategy
Determination of the Need for Exposure Measurements
The employer must determine whether employees may be exposed to concentrations in excess of the action level. This determination becomes the first step in an employee exposure monitoring program that minimizes employer sampling burdens while providing adequate employee protection. If employees may be exposed above the action level, the employer must measure exposure. Otherwise, an objective determination that employee exposure is low provides adequate evidence that exposure potential has been examined.
The employer should examine all available relevant information, eg. insurance company and trade association data and information from suppliers or exposure data collected from similar operations. The employer may also use previously-conducted sampling including area monitoring. The employer must make a determination relevant to each operation although this need not be on a separate piece of paper. If the employer can demonstrate conclusively that no employee is exposed above the action level or the STEL through the use of objective data, the employer need proceed no further on employee exposure monitoring until such time that conditions have changed and the determination is no longer valid.
If the employer cannot determine that employee exposure is less than the action level and the STEL, employee exposure monitoring will have to be conducted.
Workplace Material Survey
The primary purpose of a survey of raw material is to determine if formaldehyde is being used in the work environment and if so, the conditions under which formaldehyde is being used.
The first step is to tabulate all situations where formaldehyde is used in a manner such that it may be released into the workplace atmosphere or contaminate the skin. This information should be available through analysis of company records and information on the MSDSs available through provisions of this standard and the Hazard Communication standard.
If there is an indication from materials handling records and accompanying MSDSs that formaldehyde is being used in the following types of processes or work operations, there may be a potential for releasing formaldehyde into the workplace atmosphere:
Processes and work operations that use formaldehyde in these manners will probably require further investigation at the worksite to determine the extent of employee monitoring that should be conducted.
Workplace Observations
To this point, the only intention has been to provide an indication as to the existence of potentially exposed employees. With this information, a visit to the workplace is needed to observe work operations, to identify potential health hazards, and to determine whether any employees may be exposed to hazardous concentrations of formaldehyde.
In many circumstances, sources of formaldehyde can be identified through the sense of smell. However, this method of detection should be used with caution because of olfactory fatigue.
Employee location in relation to source of formaldehyde is important in determining if an employee may be significantly exposed to formaldehyde. In most instances, the closer a worker is to the source, the higher the probability that a significant exposure will occur.
Other characteristics should be considered. Certain high temperature operations give rise to higher evaporation rates. Locations of open doors and windows provide natural ventilation that tend to dilute formaldehyde emissions. General room ventilation also provides a measure of control.
Calculation of Potential Exposure Concentrations
By knowing the ventilation rate in a workplace and the quantity of formaldehyde generated, the employer may be able to determine by calculation if the PELs might be exceeded. To account for poor mixing of formaldehyde into the entire room, locations of fans and proximity of employees to the work operation, the employer must include a safety factor. If an employee is relatively close to a source, particularly if he or she is located downwind, a safety factor of 100 may be necessary. For other situations, a factor of 10 may be acceptable. If the employer can demonstrate through such calculations that employee exposure does not exceed the action level or the STEL, the employer may use this information as objective data to demonstrate compliance with the standard.
Sampling Strategy
Once the employer determines that there is a possibility of substantial employee exposure to formaldehyde, the employer is obligated to measure employee exposure.
The next step is selection of a maximum risk employee. When there are different processes where employees may be exposed to formaldehyde, a maximum risk employee should be selected for each work operation.
Selection of the maximum risk employee requires professional judgment. The best procedure for selecting the maximum risk employee is to observe employees and select the person closest to the source of formaldehyde. Employee mobility may affect this selection; eg. if the closest employee is mobile in his tasks, he may not be the maximum risk employee. Air movement patterns and differences in work habits will also affect selection of the maximum risk employee.
When many employees perform essentially the same task, a maximum risk employee cannot be selected. In this circumstance, it is necessary to resort to random sampling of the group of workers. The objective is to select a subgroup of adequate size so that there is a high probability that the random sample will contain at least one worker with high exposure if one exists. The number of persons in the group influences the number that need to be sampled to ensure that at least one individual from the highest 10 percent exposure group is contained in the sample. For example, to have 90 percent confidence in the results, if the group size is 10, nine should be sampled; for 50, only 18 need to be sampled.
If measurement shows exposure to formaldehyde at or above the action level or the STEL, the employer needs to identify all other employees who may be exposed at or above the action level or STEL and measure or otherwise accurately characterize the exposure of these employees.
Whether representative monitoring or random sampling are conducted, the purpose remains the same—to determine if the exposure of any employee is above the action level. If the exposure of the most exposed employee is less than the action level and the STEL, regardless of how the employee is identified, then it is reasonable to assume that measurements of exposure of the other employees in that operation would be below the action level and the STEL.
Exposure Measurements
There is no “best” measurement strategy for all situations. Some elements to consider in developing a strategy are:
Samples taken for determining compliance with the STEL differ from those that measure the TWA concentration in important ways. STEL samples are best taken in a nonrandom fashion using all available knowledge relating to the area, the individual, and the process to obtain samples during periods of maximum expected concentrations. At least three measurements on a shift are generally needed to spot gross errors or mistakes; however, only the highest value represents the STEL.
If an operation remains constant throughout the workshift, a much greater number of samples would need to be taken over the 32 discrete nonoverlapping periods in an 8-hour workshift to verify compliance with a STEL. If employee exposure is truly uniform throughout the workshift, however, an employer in compliance with the l ppm TWA would be in compliance with the 2 ppm STEL, and this determination can probably be made using objective data.
Need To Repeat the Monitoring Strategy
Interday and intraday fluctuations in employee exposure are mostly influenced by the physical processes that generate formaldehyde and the work habits of the employee. Hence, in-plant process variations influence the employer's determination of whether or not additional controls need to be imposed. Measurements that employee exposure is low on a day that is not representative of worst conditions may not provide sufficient information to determine whether or not additional engineering controls should be installed to achieve the PELs.
The person responsible for conducting sampling must be aware of systematic changes which will negate the validity of the sampling results. Systematic changes in formaldehyde exposure concentration for an employee can occur due to:
Any of these changes, if they may result in additional exposure that reaches the next level of action ( i.e. 0.5 or 1.0 ppm as an 8-hr average or 2 ppm over 15 minutes) require the employer to perform additional monitoring to reassess employee exposure.
A number of methods are suitable for measuring employee exposure to formaldehyde or for characterizing emissions within the worksite. The preamble to this standard describes some methods that have been widely used or subjected to validation testing. A detailed analytical procedure derived from the OSHA Method 52 for acrolein and formaldehyde is presented below for informational purposes.
Inclusion of OSHA's method in this appendix in no way implies that it is the only acceptable way to measure employee exposure to formaldehyde. Other methods that are free from significant interferences and that can determine formaldehyde at the permissible exposure limits within ±25 percent of the “true” value at the 95 percent confidence level are also acceptable. Where applicable, the method shou1d a1so be capab1e of measuring formaldehyde at the action level to ±35 percent of the “true” value with a 95 percent confidence level. OSHA encourages emp1oyers to choose methods that will be best for their individual needs. The employer must exercise caution, however, in choosing an appropriate method since some techniques suffer from interferences that are likely to be present in workplaces of certain industry sectors where formaldehyde is used.
OSHA's Analytical Laboratory Method
Method No:
Matrix:
Target Concentration:
3
Procedures:
Recommended Sampling Rate and Air Volumes:
Reliable Quantitation Limit:
3
Standard Error of Estimate at the Target Concentration:
Status of the Method:
Date:
1. General Discussion
1.1 Background: The current OSHA method for collecting acrolein vapor recommends the use of activated 13X molecular sieves. The samples must be stored in an ice bath during and after sampling and also they must be analyzed within 48 hours of collection. The current OSHA method for collecting formaldehyde vapor recommends the use of bubblers containing 10% methanol in water as the trapping solution.
This work was undertaken to resolve the sample stability problems associated with acrolein and also to eliminate the need to use bubb1ers to sample formaldehyde. A goal of this work was to develop and/or to evaluate a common sampling and analytical procedure for acrolein and formaldehyde.
NIOSH has developed independent methodologies for acrolein and formaldehyde which recommend the use of reagent-coated adsorbent tubes to collect the aldehydes as stable derivatives. The formaldehyde sampling tubes contain Chromosorb 102 adsorbent coated with N-benzylethanolamine (BEA) which reacts with formaldehyde vapor to form a stable oxazolidine compound. The acrolein sampling tubes contain XAD-2 adsorbent coated with 2-(hydroxymethyl)piperidine (2-HMP) which reacts with acrolein vapor to form a different, stable oxazolidine derivative. Acrolein does not appear to react with BEA to give a suitable reaction product. Therefore, the formaldehyde procedure cannot provide a common method for both aldehydes. However, formaldehyde does react with 2-HMP to form a very suitable reaction product. It is the quantitative reaction of acrolein and formaldehyde with 2-HMP that provides the basis for this evaluation.
This sampling and analytical procedure is very similar to the method recommended by NIOSH for acrolein. Some changes in the NIOSH methodology were necessary to permit the simultaneous determination of both aldehydes and also to accommodate OSHA laboratory equipment and analytical techniques.
1.2 Limit-defining parameters: The analyte air concentrations reported in this method are based on the recommended air volume for each analyte collected separately and a desorption volume of 1 mL. The amounts are presented as acrolein and/or formaldehyde, even though the derivatives are the actual species analyzed.
1.2.1 Detection limits of the analytical procedure: The detection limit of the analytical procedure was 386 pg per injection for formaldehyde. This was the amount of analyte which gave a peak whose height was about five times the height of the peak given by the residual formaldehyde derivative in a typical blank front section of the recommended sampling tube.
1.2.2 Detection limits of the overall procedure: The detection limits of the overall procedure were 482 ng per sample (16 ppb or 20 µg/m 3 for formaldehyde). This was the amount of analyte spiked on the sampling device which allowed recoveries approximately equal to the detection limit of the analytical procedure.
1.2.3 Reliable quantitation limits: The reliable quantitation limit was 482 ng per sample (16 ppb or 20 µg/m 3 ) for formaldehyde. These were the smallest amounts of analyte which could be quantitated within the limits of a recovery of at least 75% and a precision (±1.96 SD) of ±25% or better.
The reliable quantitation limit and detection limits reported in the method are based upon optimization of the instrument for the smallest possible amount of analyte. When the target concentration of an analyte is exceptionally higher than these limits, they may not be attainable at the routine operating parameters.
1.2.4 Sensitivity: The sensitivity of the analytical procedure over concentration ranges representing 0.4 to 2 times the target concentration, based on the recommended air volumes, was 7,589 area units per µg/mL for formaldehyde. This value was determined from the slope of the calibration curve. The sensitivity may vary with the particular instrument used in the analysis.
1.2.5 Recovery: The recovery of formaldehyde from samples used in an 18-day storage test remained above 92% when the samples were stored at ambient temperature. These values were determined from regression lines which were calculated from the storage data. The recovery of the analyte from the collection device must be at least 75% following storage.
1.2.6 Precision (analytical method only): The pooled coefficient of variation obtained from replicate determinations of analytical standards over the range of 0.4 to 2 times the target concentration was 0.0052 for formaldehyde (Section 4.3).
1.2.7 Precision (overall procedure): The precision at the 95% confidence level for the ambient temperature storage tests was ±14.3% for formaldehyde. These values each include an additional ±5% for sampling error. The overall procedure must provide results at the target concentrations that are ±25% at the 95% confidence level.
1.2.8 Reproducibility: Samples collected from controlled test atmospheres and a draft copy of this procedure were given to a chemist unassociated with this evaluation. The formaldehyde samples were analyzed following 15 days storage. The average recovery was 96.3% and the standard deviation was 1.7%.
1.3 Advantages:
1.3.1 The sampling and analytical procedures permit the simultaneous determination of acrolein and formaldehyde.
1.3.2 Samples are stable following storage at ambient temperature for at least 18 days.
1.4 Disadvantages: None.
2. Sampling Procedure
2.1 Apparatus:
2.1.1 Samples are collected by use of a personal sampling pump that can be calibrated to within ±5% of the recommended 0.1 L/min sampling rate with the sampling tube in line.
2.1.2 Samples are collected with laboratory prepared sampling tubes. The sampling tube is constructed of silane treated glass and is about 8-cm long. The ID is 4 mm and the OD is 6 mm. One end of the tube is tapered so that a glass wool end plug will hold the contents of the tube in place during sampling. The other end of the sampling tube is open to its full 4-mm ID to facilitate packing of the tube. Both ends of the tube are fire-polished for safety. The tube is packed with a 75-mg backup section, located nearest the tapered end and a 150-mg sampling section of pretreated XAD-2 adsorbent which has been coated with 2-HMP. The two sections of coated adsorbent are separated and retained with small plugs of silanized glass wool. Following packing, the sampling tubes are sealed with two 7/32 inch OD plastic end caps. Instructions for the pretreatment and the coating of XAD-2 adsorbent are presented in Section 4 of this method.
2.1.3 Sampling tubes, similar to those recommended in this method, are marketed by Supelco, Inc. These tubes were not available when this work was initiated; therefore, they were not evaluated.
2.2 Reagents: None required.
2.3 Technique:
2.3.1 Properly label the sampling tube before sampling and then remove the plastic end caps.
2.3.2 Attach the sampling tube to the pump using a section of flexible plastic tubing such that the large, front section of the sampling tube is exposed directly to the atmosphere. Do not place any tubing ahead of the sampling tube. The sampling tube should be attached in the worker's breathing zone in a vertical manner such that it does not impede work performance.
2.3.3 After sampling for the appropriate time, remove the sampling tube from the pump and then seal the tube with plastic end caps.
2.3.4 Include at least one blank for each sampling set. The blank should be handled in the same manner as the samples with the exception that air is not drawn through it.
2.3.5 List any potential interferences on the sample data sheet.
2.4 Breakthrough:
2.4.1 Breakthrough was defined as the relative amount of analyte found on a backup sample in relation to the total amount of analyte collected on the sampling train.
2.4.2 For formaldehyde collected from test atmospheres containing 6 times the PEL, the average 5% breakthrough air volume was 41 L. The sampling rate was 0.1 L/min and the average mass of formaldehyde collected was 250 µg.
2.5 Desorption Efficiency: No desorption efficiency corrections are necessary to compute air sample results because analytical standards are prepared using coated adsorbent. Desorption efficiencies were determined, however, to investigate the recoveries of the analytes from the sampling device. The average recovery over the range of 0.4 to 2 times the target concentration, based on the recommended air volumes, was 96.2% for formaldehyde. Desorption efficiencies were essentially constant over the ranges studied.
2.6 Recommended Air Volume and Sampling Rate:
2.6.1 The recommended air volume for formaldehyde is 24 L.
2.6.2 The recommended sampling rate is 0.1 L/min.
2.7 Interferences:
2.7.1 Any collected substance that is capable of reacting 2-HMP and thereby depleting the derivatizing agent is a potential interference. Chemicals which contain a carbonyl group, such as acetone, may be capable or reacting with 2-HMP.
2.7.2 There are no other known interferences to the sampling method.
2.8 Safety Precautions:
2.8.1 Attach the sampling equipment to the worker in such a manner that it well not interfere with work performance or safety.
2.8.2 Follow all safety practices that apply to the work area being sampled.
3. Analytical Procedure
3.1 Apparatus:
3.1.1 A gas chromatograph (GC), equipped with a nitrogen selective detector. A Hewlett-Packard Model 5840A GC fitted with a nitrogen-phosphorus flame ionization detector (NPD) was used for this evaluation. Injections were performed using a Hewlett-Packard Model 7671A automatic sampler.
3.1.2 A GC column capable of resolving the analytes from any interference. A 6 ft × 1/4 in OD (2mm ID) glass GC column containing 10% UCON 50-HB-5100 + 2% KOH on 80/100 mesh Chromosorb W-AW was used for the evaluation. Injections were performed on-column.
3.1.3 Vials, glass 2-mL with Teflon-lined caps.
3.1.4 Volumetric flasks, pipets, and syringes for preparing standards, making dilutions, and performing injections.
3.2 Reagents:
3.2.1 Toluene and dimethylformamide. Burdick and Jackson solvents were used in this evaluation.
3.2.2 Helium, hydrogen, and air, GC grade.
3.2.3 Formaldehyde, 37%, by weight, in water. Aldrich Chemical, ACS Reagent Grade formaldehyde was used in this evaluation.
3.2.4 Amberlite XAD-2 adsorbent coated with 2-(hydroxymethyl—piperidine (2-HMP), 10% by weight (Section 4).
3.2.5 Desorbing solution with internal standard. This solution was prepared by adding 20 µL of dimethylformamide to 100 mL of toluene.
3.3 Standard preparation:
3.3.1 Formaldehyde: Prepare stock standards by diluting known volumes of 37% formaldehyde solution with methanol. A procedure to determine the formaldehyde content of these standards is presented in Section 4. A standard containing 7.7 mg/mL formaldehyde was prepared by diluting 1 mL of the 37% reagent to 50 mL with methanol.
3.3.2 It is recommended that analytical standards be prepared about 16 hours before the air samples are to be analyzed in order to ensure the complete reaction of the analytes with 2-HMP. However, rate studies have shown the reaction to be greater than 95% complete after 4 hours. Therefore, one or two standards can be analyzed after this reduced time if sample results are outside the concentration range of the prepared standards.
3.3.3 Place 150-mg portions of coated XAD-2 adsorbent, from the same lot number as used to collect the air samples, into each of several glass 2-mL vials. Seal each vial with a Teflon-lined cap.
3.3.4 Prepare fresh analytical standards each day by injecting appropriate amounts of the diluted analyte directly onto 150-mg portions of coated adsorbent. It is permissible to inject both acrolein and formaldehyde on the same adsorbent portion. Allow the standards to stand at room temperature. A standard, approximately the target levels, was prepared by injecting 11 µL of the acrolein and 12 µL of the formaldehyde stock standards onto a single coated XAD-2 adsorbent portion.
3.3.5 Prepare a sufficient number of standards to generate the calibration curves. Analytical standard concentrations should bracket sample concentrations. Thus, if samples are not in the concentration range of the prepared standards, additional standards must be prepared to determine detector response.
3.3.7 Desorb the standards in the same manner as the samples following the 16-hour reaction time.
3.4 Sample preparation:
3.4.1 Transfer the 150-mg section of the sampling tube to a 2-mL vial. Place the 75-mg section in a separate vial. If the glass wool plugs contain a significant number of adsorbent beads, place them with the appropriate sampling tube section. Discard the glass wool plugs if they do not contain a significant number of adsorbent beads.
3.4.2 Add 1 mL of desorbing solution to each vial.
3.4.3 Seal the vials with Teflon-lined caps and then allow them to desorb for one hour. Shake the vials by hand with vigorous force several times during the desorption time.
3.4.4 Save the used sampling tubes to be cleaned and recycled.
3.5 Analysis:
3.5.1 GC Conditions
Column Temperature:
Bi-level temperature program—First level: 100 to 140 °C at 4 °C/min following completion of the first level.
Second level: 140 to 180 °C at 20 °C/min following completion of the first level.
Isothermal period: Hold column at 180 °C until the recorder pen returns to baseline (usually about 25 min after injection).
Injector temperature: 180 °C
Helium flow rate:
Injection volume: 0.8 µL
GC column:
1/4
NPD conditions:
Hydrogen flow rate: 3 mL/min
Air flow rate: 50 mL/min
Detector temperature: 275 °C
3.5.2 Chromatogram: For an example of a typical chromatogram, see Figure 4.11 in OSHA Method 52.
3.5.3 Use a suitable method, such as electronic integration, to measure detector response.
3.5.4 Use an internal standard method to prepare the calibration curve with several standard solutions of different concentrations. Prepare the calibration curve daily. Program the integrator to report results in µg/mL.
3.5.5 Bracket sample concentrations with standards.
3.6 Interferences (Analytical)
3.6.1 Any compound with the same general retention time as the analytes and which also gives a detector response is a potential interference. Possible interferences should be reported to the laboratory with submitted samples by the industrial hygienist.
3.6.2 GC parameters (temperature, column, etc.) may be changed to circumvent interferences.
3.6.3 A useful means of structure designation is GC/MS. It is recommended this procedure be used to confirm samples whenever possible.
3.6.4 The coated adsorbent usually contains a very small amount of residual formaldehyde derivative (Section 4.8).
3.7 Calculations:
3.7.1 Results are obtained by use of calibration curves. Calibration curves are prepared by plotting detector response against concentration for each standard. The best line through the data points is determined by curve fitting.
3.7.2 The concentration, in µg/mL, for a particular sample is determined by comparing its detector response to the calibration curve. If either of the analytes is found on the backup section, it is added to the amount found on the front section. Blank corrections should be performed before adding the results together.
3.7.3 The acrolein and/or formaldehyde air concentration can be expressed using the following equation:
3
where A = µg/mL from 3.7.2, B = desorption volume, and C = L of air sampled.
No desorption efficiency corrections are required.
3.7.4 The following equation can be used to convert results in mg/m 3 to ppm.
3
3
4. Backup Data
4.1 Backup data on detection limits, reliable quantitation limits, sensitivity and precision of the analytical method, breakthrough, desorption efficiency, storage, reproducibility, and generation of test atmospheres are available in OSHA Method 52, developed by the Organics Methods Evaluation Branch, OSHA Analytical Laboratory, Salt Lake City, Utah.
4.2 Procedure to Coat XAD-2 Adsorbent with 2-HMP:
4.2.1 Apparatus: Soxhlet extraction apparatus, rotary evaporation apparatus, vacuum dessicator, 1-L vacuum flask, 1-L round-bottomed evaporative flask, 1-L Erlenmeyer flask, 250-mL Buchner funnel with a coarse fritted disc, etc.
4.2.2 Reagents:
4.2.2.1 Methanol, isooctane, and toluene.
4.2.2.2 2-(Hydroxymethyl)piperidine.
4.2.2.3 Amberlite XAD-2 non-ionic polymeric adsorbent, 20 to 60 mesh, Aldrich Chemical XAD-2 was used in this evaluation.
4.2.3 Procedure: Weigh 125 g of crude XAD-2 adsorbent into a 1-L Erlenmeyer flask. Add about 200 mL of water to the flask and then swirl the mixture to wash the adsorbent. Discard any adsorbent that floats to the top of the water and then filter the mixture using a fritted Buchner funnel. Air dry the adsorbent for 2 minutes. Transfer the adsorbent back to the Erlenmeyer flask and then add about 200 mL of methanol to the flask. Swirl and then filter the mixture as before. Transfer the washed adsorbent back to the Erlenmeyer flask and then add about 200 mL of methanol to the flask. Swirl and then filter the mixture as before. Transfer the washed adsorbent to a 1-L round-bottomed evaporative flask, add 13 g of 2-HMP and then 200 mL of methanol, swirl the mixture and then allow it to stand for one hour. Remove the methanol at about 40 °C and reduced pressure using a rotary evaporation apparatus. Transfer the coated adsorbent to a suitable container and store it in a vacuum desiccator at room temperature overnight. Transfer the coated adsorbent to a Soxhlet extractor and then extract the material with toluene for about 24 hours. Discard the contaminated toluene, add methanol in its place and then continue the Soxhlet extraction for an additional 4 hours. Transfer the adsorbent to a weighted 1-L round-bottom evaporative flask and remove the methanol using the rotary evaporation apparatus. Determine the weight of the adsorbent and then add an amount of 2-HMP, which is 10% by weight of the adsorbent. Add 200 mL of methanol and then swirl the mixture. Allow the mixture to stand for one hour. Remove the methanol by rotary evaporation. Transfer the coated adsorbent to a suitable container and store it in a vacuum desiccator until all traces of solvents are gone. Typically, this will take 2-3 days. The coated adsorbent should be protected from contamination. XAD-2 adsorbent treated in this manner will probably not contain residual acrolein derivative. However, this adsorbent will often contain residual formaldehyde derivative levels of about 0.1 µg per 150 mg of adsorbent. If the blank values for a batch of coated adsorbent are too high, then the batch should be returned to the Soxhlet extractor, extracted with toluene again and then recoated. This process can be repeated until the desired blank levels are attained.
The coated adsorbent is now ready to be packed into sampling tubes. The sampling tubes should be stored in a sealed container to prevent contamination. Sampling tubes should be stored in the dark at room temperature. The sampling tubes should be segregated by coated adsorbent lot number. A sufficient amount of each lot number of coated adsorbent should be retained to prepare analytical standards for use with air samples from that lot number.
4.3 A Procedure to Determine Formaldehyde by Acid Titration: Standardize the 0.1 N HCl solution using sodium carbonate and methyl orange indicator.
Place 50 mL of 0.1 M sodium sulfite and three drops of thymophthalein indicator into a 250-mL Erlenmeyer flask. Titrate the contents of the flask to a colorless endpoint with 0.1 N HCl (usually one or two drops is sufficient). Transfer 10 mL of the formaldehyde/methanol solution (prepared in 3.3.1) into the same flask and titrate the mixture with 0.1 N HCl, again, to a colorless endpoint. The formaldehyde concentration of the standard may be calculated by the following equation:
This method is based on the quantitative liberation of sodium hydroxide when formaldehyde reacts with sodium sulfite to form the formaldehyde-bisulfite addition product. The volume of sample may be varied depending on the formaldehyde content but the solution to be titrated must contain excess sodium sulfite. Formaldehyde solutions containing substantial amounts of acid or base must be neutralized before analysis.
Appendix C to § 1910.1048—Medical Surveillance—Formaldehyde
I. Health Hazards
The occupational health hazards of formaldehyde are primarily due to its toxic effects after inhalation, after direct contact with the skin or eyes by formaldehyde in liquid or vapor form, and after ingestion.
II. Toxicology
A. Acute Effects of Exposure
1. Inhalation (breathing): Formaldehyde is highly irritating to the upper airways. The concentration of formaldehyde that is immediately dangerous to life and health is 100 ppm. Concentrations above 50 ppm can cause severe pulmonary reactions within minutes. These include pulmonary edema, pneumonia, and bronchial irritation which can result in death. Concentrations above 5 ppm readily cause lower airway irritation characterized by cough, chest tightness and wheezing. There is some controversy regarding whether formaldehyde gas is a pulmonary sensitizer which can cause occupational asthma in a previously normal individual. Formaldehyde can produce symptoms of bronchial asthma in humans. The mechanism may be either sensitization of the individual by exposure to formaldehyde or direct irritation by formaldehyde in persons with pre-existing asthma. Upper airway irritation is the most common respiratory effect reported by workers and can occur over a wide range of concentrations, most frequently above 1 ppm. However, airway irritation has occurred in some workers with exposures to formaldehyde as low as 0.1 ppm. Symptoms of upper airway irritation include dry or sore throat, itching and burning sensations of the nose, and nasal congestion. Tolerance to this level of exposure may develop within 1-2 hours. This tolerance can permit workers remaining in an environment of gradually increasing formaldehyde concentrations to be unaware of their increasingly hazardous exposure.
2. Eye contact: Concentrations of formaldehyde between 0.05 ppm and 0.5 ppm produce a sensation of irritation in the eyes with burning, itching, redness, and tearing. Increased rate of blinking and eye closure generally protects the eye from damage at these low levels, but these protective mechanisms may interfere with some workers' work abilities. Tolerance can occur in workers continuously exposed to concentrations of formaldehyde in this range. Accidental splash injuries of human eyes to aqueous solutions of formaldehyde (formalin) have resulted in a wide range of ocular injuries including corneal opacities and blindness. The severity of the reactions have been directly dependent on the concentration of formaldehyde in solution and the amount of time lapsed before emergency and medical intervention.
3. Skin contact: Exposure to formaldehyde solutions can cause irritation of the skin and allergic contact dermatitis. These skin diseases and disorders can occur at levels well below those encountered by many formaldehyde workers. Symptoms include erythema, edema, and vesiculation or hives. Exposure to liquid formalin or formaldehyde vapor can provoke skin reactions in sensitized individuals even when airborne concentrations of formaldehyde are well below 1 ppm.
4. Ingestion: Ingestion of as little as 30 ml of a 37 percent solution of formaldehyde (formalin) can result in death. Gastrointestinal toxicity after ingestion is most severe in the stomach and results in symptoms which can include nausea, vomiting, and servere abdominal pain. Diverse damage to other organ systems including the liver, kidney, spleen, pancreas, brain, and central nervous systems can occur from the acute response to ingestion of formaldehyde.
B. Chronic Effects of Exposure
Long term exposure to formaldehyde has been shown to be associated with an increased risk of cancer of the nose and accessory sinuses, nasopharyngeal and oropharyngeal cancer, and lung cancer in humans. Animal experiments provide conclusive evidence of a causal relationship between nasal cancer in rats and formaldehyde exposure. Concordant evidence of carcinogenicity includes DNA binding, genotoxicity in short-term tests, and cytotoxic changes in the cells of the target organ suggesting both preneoplastic changes and a dose-rate effect. Formaldehyde is a complete carcinogen and appears to exert an effect on at least two stages of the carcinogenic process.
III. Surveillance considerations
A. History
1. Medical and occupational history: Along with its acute irritative effects, formaldehyde can cause allergic sensitization and cancer. One of the goals of the work history should be to elicit information on any prior or additional exposure to formaldehyde in either the occupational or the non-occupational setting.
2. Respiratory history: As noted above, formaldehyde has recognized properties as an airway irritant and has been reported by some authors as a cause of occupational asthma. In addition, formaldehyde has been associated with cancer of the entire respiratory system of humans. For these reasons, it is appropriate to include a comprehensive review of the respiratory system in the medical history. Components of this history might include questions regarding dyspnea on exertion, shortness of breath, chronic airway complaints, hyperreactive airway disease, rhinitis, bronchitis, bronchiolitis, asthma, emphysema, respiratory allergic reaction, or other preexisting pulmonary disease.
In addition, generalized airway hypersensitivity can result from exposures to a single sensitizing agent. The examiner should, therefore, elicit any prior history of exposure to pulmonary irritants, and any short- or long-term effects of that exposure.
Smoking is known to decrease mucociliary clearance of materials deposited during respiration in the nose and upper airways. This may increase a worker's exposure to inhaled materials such as formaldehyde vapor. In addition, smoking is a potential confounding factor in the investigation of any chronic respiratory disease, including cancer. For these reasons, a complete smoking history should be obtained.
3. Skin Disorders: Because of the dermal irritant and sensitizing effects of formaldehyde, a history of skin disorders should be obtained. Such a history might include the existence of skin irritation, previously documented skin sensitivity, and other dermatologic disorders. Previous exposure to formaldehyde and other dermal sensitizers should be recorded.
4. History of atopic or allergic diseases: Since formaldehyde can cause allergic sensitization of the skin and airways, it might be useful to identify individuals with prior allergen sensitization. A history of atopic disease and allergies to formaldehyde or any other substances should also be obtained. It is not definitely known at this time whether atopic diseases and allergies to formaldehyde or any other substances should also be obtained. Also it is not definitely known at this time whether atopic individuals have a greater propensity to develop formaldehyde sensitivity than the general population, but identification of these individuals may be useful for ongoing surveillance.
5. Use of disease questionnaires: Comparison of the results from previous years with present results provides the best method for detecting a general deterioration in health when toxic signs and symptoms are measured subjectively. In this way recall bias does not affect the results of the analysis. Consequently, OSHA has determined that the findings of the medical and work histories should be kept in a standardized form for comparison of the year-to-year results.
B. Physical Examination
1. Mucosa of eyes and airways: Because of the irritant effects of formaldehyde, the examining physician should be alert to evidence of this irritation. A speculum examination of the nasal mucosa may be helpful in assessing possible irritation and cytotoxic changes, as may be indirect inspection of the posterior pharynx by mirror.
2. Pulmonary system: A conventional respiratory examination, including inspection of the thorax and auscultation and percussion of the lung fields should be performed as part of the periodic medical examination. Although routine pulmonary function testing is only required by the standard once every year for persons who are exposed over the TWA concentration limit, these tests have an obvious value in investigating possible respiratory dysfunction and should be used wherever deemed appropriate by the physician. In cases of alleged formaldehyde-induced airway disease, other possible causes of pulmonary disfunction (including exposures to other substances) should be ruled out. A chest radiograph may be useful in these circumstances. In cases of suspected airway hypersensitivity or allergy, it may be appropriate to use bronchial challenge testing with formaldehyde or methacholine to determine the nature of the disorder. Such testing should be performed by or under the supervision of a physician experienced in the procedures involved.
3. Skin: The physician should be alert to evidence of dermal irritation of sensitization, including reddening and inflammation, urticaria, blistering, scaling, formation of skin fissures, or other symptoms. Since the integrity of the skin barrier is compromised by other dermal diseases, the presence of such disease should be noted. Skin sensitivity testing carries with it some risk of inducing sensitivity, and therefore, skin testing for formaldehyde sensitivity should not be used as a routine screening test. Sensitivity testing may be indicated in the investigation of a suspected existing sensitivity. Guidelines for such testing have been prepared by the North American Contact Dermatitis Group.
C. Additional Examinations or Tests
The physician may deem it necessary to perform other medical examinations or tests as indicated. The standard provides a mechanism whereby these additional investigations are covered under the standard for occupational exposure to formaldehyde.
D. Emergencies
The examination of workers exposed in an emergency should be directed at the organ systems most likely to be affected. Much of the content of the examination will be similar to the periodic examination unless the patient has received a severe acute exposure requiring immediate attention to prevent serious consequences. If a severe overexposure requiring medical intervention or hospitalization has occurred, the physician must be alert to the possibility of delayed symptoms. Followup nonroutine examinations may be necessary to assure the patient's well-being.
E. Employer Obligations
The employer is required to provide the physician with the following information: A copy of this standard and appendices A, C, D, and E; a description of the affected employee's duties as they relate to his or her exposure concentration; an estimate of the employee's exposure including duration (e.g., 15 hr/wk, three 8-hour shifts, full-time); a description of any personal protective equipment, including respirators, used by the employee; and the results of any previous medical determinations for the affected employee related to formaldehyde exposure to the extent that this information is within the employer's control.
F. Physician's Obligations
The standard requires the employer to obtain a written statement from the physician. This statement must contain the physician's opinion as to whether the employee has any medical condition which would place him or her at increased risk of impaired health from exposure to formaldehyde or use of respirators, as appropriate. The physician must also state his opinion regarding any restrictions that should be placed on the employee's exposure to formaldehyde or upon the use of protective clothing or equipment such as respirators. If the employee wears a respirator as a result of his or her exposure to formaldehyde, the physician's opinion must also contain a statement regarding the suitability of the employee to wear the type of respirator assigned. Finally, the physician must inform the employer that the employee has been told the results of the medical examination and of any medical conditions which require further explanation or treatment. This written opinion is not to contain any information on specific findings or diagnoses unrelated to occupational exposure to formaldehyde.
The purpose in requiring the examining physician to supply the employer with a written opinion is to provide the employer with a medical basis to assist the employer in placing employees initially, in assuring that their health is not being inpaired by formaldehyde, and to assess the employee's ability to use any required protective equipment.
Appendix D to § 1910.1048—Nonmandatory Medical Disease Questionnaire
[57 FR 22310, May 27, 1992; 57 FR 27161, June 18, 1992; 61 FR 5508, Feb. 13, 1996; 63 FR 1292, Jan. 8, 1998; 63 FR 20099, Apr. 23, 1998; 70 FR 1143, Jan. 5, 2005; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50190, Aug. 24, 2006; 73 FR 75586, Dec. 12, 2008; 77 FR 17784, Mar. 26, 2012; 84 FR 21518, May 14, 2019]
For the purpose of this section, the following definitions shall apply:
Action level means a concentration of airborne MDA of 5 ppb as an eight (8)-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer whose duties require the person to enter a regulated area, or any person entering such an area as a designated representative of employees, for the purpose of exercising the right to observe monitoring and measuring procedures under paragraph (o) of this section, or any other person authorized by the Act or regulations issued under the Act.
Container means any barrel, bottle, can, cylinder, drum, reaction vessel, storage tank, commercial packaging or the like, but does not include piping systems.
Dermal exposure to MDA occurs where employees are engaged in the handling, application or use of mixtures or materials containing MDA, with any of the following non-airborne forms of MDA:
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment which results in an unexpected and potentially hazardous release of MDA.
Employee exposure means exposure to MDA which would occur if the employee were not using respirators or protective work clothing and equipment.
Finished article containing MDA is defined as a manufactured item:
4,4′ Methylenedianiline or MDA means the chemical, 4,4′-diaminodiphenylmethane, Chemical Abstract Service Registry number 101-77-9, in the form of a vapor, liquid, or solid. The definition also includes the salts of MDA.
Regulated areas means areas where airborne concentrations of MDA exceed or can reasonably be expected to exceed, the permissible exposure limits, or where dermal exposure to MDA can occur.
STEL means short term exposure limit as determined by any 15 minute sample period.
The employer shall assure that no employee is exposed to an airborne concentration of MDA in excess of ten parts per billion (10 ppb) as an 8-hour time-weighted average or a STEL of 100 ppb.
Where there is the possibility of employee exposure to MDA due to an emergency, means shall be developed to alert promptly those employees who have the potential to be directly exposed. Affected employees not engaged in correcting emergency conditions shall be evacuated immediately in the event that an emergency occurs. Means shall also be developed and implemented for alerting other employees who may be exposed as a result of the emergency.
Each employer who has a workplace or work operation covered by this standard shall perform initial monitoring to determine accurately the airborne concentrations of MDA to which employees may be exposed.
The employer shall institute the exposure monitoring required under paragraphs (e)(2) and (e)(3) of this section when there has been a change in production process, chemicals present, control equipment, personnel, or work practices which may result in new or additional exposures to MDA, or when the employer has any reason to suspect a change which may result in new or additional exposures.
Monitoring shall be accurate, to a confidence level of 95 percent, to within plus or minus 25 percent for airborne concentrations of MDA.
The employer shall make routine inspections of employee hands, face and forearms potentially exposed to MDA. Other potential dermal exposures reported by the employee must be referred to the appropriate medical personnel for observation. If the employer determines that the employee has been exposed to MDA the employer shall:
The employer shall establish regulated areas where airborne concentrations of MDA exceed or can reasonably be expected to exceed, the permissible exposure limits.
Where employees are subject to dermal exposure to MDA the employer shall establish those work areas as regulated areas.
Regulated areas shall be demarcated from the rest of the workplace in a manner that minimizes the number of persons potentially exposed.
Access to regulated areas shall be limited to authorized persons.
Each person entering a regulated area shall be supplied with, and required to use, the appropriate personal protective clothing and equipment in accordance with paragraphs (h) and (i) of this section.
The employer shall ensure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in regulated areas.
Employee rotation shall not be permitted as a means of reducing exposure.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer must implement a respiratory protection program in accordance with § 1910.134 (b) through (d) (except (d)(1)(iii)), and (f) through (m), which covers each employee required by this section to use a respirator.
Where employees are subject to dermal exposure to MDA, where liquids containing MDA can be splashed into the eyes, or where airborne concentrations of MDA are in excess of the PEL, the employer shall provide, at no cost to the employee, and ensure that the employee uses, appropriate protective work clothing and equipment which prevent contact with MDA such as, but not limited to:
DANGER
MDA
MAY CAUSE CANCER
CAUSES DAMAGE TO THE LIVER
RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING MAY BE REQUIRED IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
MDA
MAY CAUSE CANCER
LIVER TOXIN
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE CLOTHING MAY BE REQUIRED TO BE WORN IN THIS AREA
Prior to June 1, 2015, employers may include the following information workplace labels in lieu of the labeling requirements in paragraph (k)(1) of this section:
DANGER
CONTAINS MDA
MAY CAUSE CANCER
LIVER TOXIN
DANGER
CONTAINS MDA
CONTAINS MATERIALS WHICH MAY CAUSE CANCER
LIVER TOXIN
In meeting the obligation to provide safety data sheets, employers shall make appropriate use of the information found in Appendices A and B to § 1910.1050.
If the employer determines that the employee has been exposed to a potentially hazardous amount of MDA in an emergency situation as addressed in paragraph (d) of this section, the employer shall provide medical examinations in accordance with paragraphs (m)(3)(i) and (ii) of this section. If the results of liver function testing indicate an abnormality, the employee shall be removed in accordance with paragraph (m)(9) of this section. Repeat liver function tests shall be conducted on the advice of the physician. If the results of the tests are normal, tests must be repeated two to three weeks from the initial testing. If the results of the second set of tests are normal and, on the advice of the physician, no additional testing is required.
Where the employee develops signs and symptoms associated with exposure to MDA, the employer shall provide the employee with an additional medical examination including a liver function test. Repeat liver function tests shall be conducted on the advice of the physician. If the results of the tests are normal, tests must be repeated two to three weeks from the initial testing. If the results of the second set of tests are normal and, on the advice of the physician, no additional testing is required.
The employee shall be removed from work environments in which exposure to MDA is at or above the action level or where dermal exposure to MDA may occur, following an initial examination (paragraph (m)(2) of this section), periodic examinations (paragraph (m)(3) of this section), an emergency situation paragraph (m)(4) of this section, or an additional examination (paragraph (m)(5) of this section) in the following circumstances:
Where the physician review mechanism used pursuant to the medical surveillance provisions of this section, has not yet resulted in a final medical determination with respect to an employee, the employer shall act as follows:
The employer may remove the employee from exposure to MDA, provide special protective measures to the employee, or place limitations upon the employee, consistent with the medical findings, determinations, or recommendations of any of the physicians who have reviewed the employee's health status.
The employer may return the employee to his or her former job status, and end any special protective measures provided to the employee, consistent with the medical findings, determinations, or recommendations of any of the physicians who have reviewed the employee's health status, with two exceptions.
The employer shall provide to an employee up to six (6) months of medical removal protection benefits on each occasion that an employee is removed from exposure to MDA or otherwise limited pursuant to this section.
For the purposes of this section, the requirement that an employer provide medical removal protection benefits means that the employer shall maintain the earnings, seniority, and other employment rights and benefits of an employee as though the employee had not been removed from normal exposure to MDA or otherwise limited.
If a removed employee files a claim for workers' compensation payments for a MDA-related disability, then the employer shall continue to provide medical removal protection benefits pending disposition of the claim. To the extent that an award is made to the employee for earnings lost during the period of removal, the employer's medical removal protection obligation shall be reduced by such amount. The employer shall receive no credit for workers' compensation payments received by the employee for treatment-related expenses.
The employer's obligation to provide medical removal protection benefits to a removed employee shall be reduced to the extent that the employee receives compensation for earnings lost during the period of removal either from a publicly or employer-funded compensation program, or receives income from non-MDA-related employment with any employer made possible by virtue of the employee's removal.
Where an employer, although not required by this section to do so, removes an employee from exposure to MDA or otherwise places limitations on an employee due to the effects of MDA exposure on the employee's medical condition, the employer shall provide medical removal protection benefits to the employee equal to that required by paragraph (m)(9)(v) of this section.
The employer shall comply with the requirements involving transfer of records set forth in 29 CFR 1910.1020(h).
The employer shall provide affected employees, or their designated representatives, an opportunity to observe the measuring or monitoring of employee exposure to MDA conducted pursuant to paragraph (e) of this section.
When observation of the measuring or monitoring of employee exposure to MDA requires entry into areas where the use of protective clothing and equipment or respirators is required, the employer shall provide the observer with personal protective clothing and equipment or respirators required to be worn by employees working in the area, assure the use of such clothing and equipment or respirators, and require the observer to comply with all other applicable safety and health procedures.
The information contained in Appendices A, B, C, and D of this section is not intended, by itself, to create any additional obligations not otherwise imposed by this standard nor detract from any existing obligation.
Appendix A to § 1910.1050—Substance Data Sheet, for 4,4′-Methylenedianiline
I. Substance Identification
A. Substance: Methylenedianiline (MDA)
B. Permissible Exposure:
1. Airborne: Ten parts per billion parts of air (10 ppb), time-weighted average (TWA) for an 8-hour workday and an action level of five parts per billion parts of air (5 ppb).
2. Dermal: Eye contact and skin contact with MDA are not permitted.
C. Appearance and odor: White to tan solid; amine odor
II. Health Hazard Data
A. Ways in which MDA affects your health. MDA can affect your health if you inhale it, or if it comes in contact with your skin or eyes. MDA is also harmful if you happen to swallow it. Do not get MDA in eyes, on skin, or on clothing.
B. Effects of overexposure. 1. Short-term (acute) overexposure: Overexposure to MDA may produce fever, chills, loss of appetite, vomiting, jaundice. Contact may irritate skin, eyes and mucous membranes. Sensitization may occur.
2. Long-term (chronic) exposure. Repeated or prolonged exposure to MDA, even at relatively low concentrations, may cause cancer. In addition, damage to the liver, kidneys, blood, and spleen may occur with long term exposure.
3. Reporting signs and symptoms. You should inform your employer if you develop any signs or symptoms which you suspect are caused by exposure to MDA including yellow staining of the skin.
III. Protective Clothing and Equipment
A. Respirators. Respirators are required for those operations in which engineering controls or work-practice controls are not adequate or feasible to reduce exposure to the permissible limit. If respirators are worn, they must have a label issued by the National Institute for Occupational Safety and Health under the provisions of 42 CFR part 84 stating that the respirators have been approved for this purpose, and cartridges and canisters must be replaced in accordance with the requirements of 29 CFR 1910.134. If you experience difficulty breathing while wearing a respirator, you can request a positive-pressure respirator from your employer. You must be thoroughly trained to use the assigned respirator, and the training must be provided by your employer.
MDA does not have a detectable odor except at levels well above the permissible exposure limits. Do not depend on odor to warn you when a respirator canister is exhausted. If you can smell MDA while wearing a respirator, proceed immediately to fresh air. If you experience difficulty breathing while wearing a respirator, tell your employer.
B. Protective Clothing. You may be required to wear coveralls, aprons, gloves, face shields, or other appropriate protective clothing to prevent skin contact with MDA. Where protective clothing is required, your employer is required to provide clean garments to you, as necessary, to assure that the clothing protects you adequately. Replace or repair impervious clothing that has developed leaks.
MDA should never be allowed to remain on the skin. Clothing and shoes which are not impervious to MDA should not be allowed to become contaminated with MDA, and if they do, the clothing and shoes should be promptly removed and decontaminated. The clothing should be laundered to remove MDA or discarded. Once MDA penetrates shoes or other leather articles, they should not be worn again.
C. Eye protection. You must wear splashproof safety goggles in areas where liquid MDA may contact your eyes. Contact lenses should not be worn in areas where eye contact with MDA can occur. In addition, you must wear a face shield if your face could be splashed with MDA liquid.
IV. Emergency and First Aid Procedures
A. Eye and face exposure. If MDA is splashed into the eyes, wash the eyes for at least 15 minutes. See a doctor as soon as possible.
B. Skin exposure. If MDA is spilled on your clothing or skin, remove the contaminated clothing and wash the exposed skin with large amounts of soap and water immediately. Wash contaminated clothing before you wear it again.
C. Breathing. If you or any other person breathes in large amounts of MDA, get the exposed person to fresh air at once. Apply artificial respiration if breathing has stopped. Call for medical assistance or a doctor as soon as possible. Never enter any vessel or confined space where the MDA concentration might be high without proper safety equipment and at least one other person present who will stay outside. A life line should be used.
D. Swallowing. If MDA has been swallowed and the patient is conscious, do not induce vomiting. Call for medical assistance or a doctor immediately.
V. Medical Requirements
If you are exposed to MDA at a concentration at or above the action level for more than 30 days per year, or exposed to liquid mixtures more than 15 days per year, your employer is required to provide a medical examination, including a medical history and laboratory tests, within 60 days of the effective date of this standard and annually thereafter. These tests shall be provided without cost to you. In addition, if you are accidentally exposed to MDA (either by ingestion, inhalation, or skin/eye contact) under conditions known or suspected to constitute toxic exposure to MDA, your employer is required to make special examinations and tests available to you.
VI. Observation of Monitoring
Your employer is required to perform measurements that are representative of your exposure to MDA and you or your designated representative are entitled to observe the monitoring procedure. You are entitled to observe the steps taken in the measurement procedure and to record the results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and equipment are required to be worn, you and your representative must also be provided with, and must wear, the protective clothing and equipment.
VII. Access to Records
You or your representative are entitled to see the records of measurements of your exposure to MDA upon written request to your employer. Your medical examination records can be furnished to your physician or designated representative upon request by you to your employer.
VIII. Precautions for Safe Use, Handling and Storage
A. Material is combustible. Avoid strong acids and their anhydrides. Avoid strong oxidants. Consult supervisor for disposal requirements.
B. Emergency clean-up. Wear self-contained breathing apparatus and fully clothe the body in the appropriate personal protective clothing and equipment.
Appendix B to § 1910.1050—Substance Technical Guidelines, MDA
I. Identification
A. Substance identification.
1. Synonyms: CAS No. 101-77-9. 4,4′-methylenedianiline; 4,4′-methylenebisaniline; methylenedianiline; dianilinomethane.
2. Formula: C 13 H 14 N 2
II. Physical Data
1. Appearance and Odor: White to tan solid; amine odor
2. Molecular Weight: 198.26
3. Boiling Point: 398-399 degrees C at 760 mm Hg
4. Melting Point: 88-93 degrees C (190-100 degrees F)
5. Vapor Pressure: 9 mmHg at 232 degrees C
6. Evaporation Rate (n-butyl acetate = 1): Negligible
7. Vapor Density (Air = 1): Not Applicable
8. Volatile Fraction by Weight: Negligible
9. Specific Gravity (Water = 1): Slight
10. Heat of Combustion: −8.40 kcal/g
11. Solubility in Water: Slightly soluble in cold water, very soluble in alcohol, benzene, ether, and many organic solvents.
III. Fire, Explosion, and Reactivity Hazard Data
1. Flash Point: 190 degrees C (374 degrees F) Setaflash closed cup
2. Flash Point: 226 degrees C (439 degrees F) Cleveland open cup
3. Extinguishing Media: Water spray; Dry Chemical; Carbon dioxide.
4. Special Fire Fighting Procedures: Wear self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes.
5. Unusual Fire and Explosion Hazards: Fire or excessive heat may cause production of hazardous decomposition products.
IV. Reactivity Data
1. Stability: Stable
2. Incompatibility: Strong oxidizers
3. Hazardous Decomposition Products: As with any other organic material, combustion may produce carbon monoxide. Oxides of nitrogen may also be present.
4. Hazardous Polymerization: Will not occur.
V. Spill and Leak Procedures
1. Sweep material onto paper and place in fiber carton.
2. Package appropriately for safe feed to an incinerator or dissolve in compatible waste solvents prior to incineration.
3. Dispose of in an approved incinerator equipped with afterburner and scrubber or contract with licensed chemical waste disposal service.
4. Discharge treatment or disposal may be subject to federal, state, or local laws.
5. Wear appropriate personal protective equipment.
VI. Special Storage and Handling Precautions
A. High exposure to MDA can occur when transferring the substance from one container to another. Such operations should be well ventilated and good work practices must be established to avoid spills.
B. Pure MDA is a solid with a low vapor pressure. Grinding or heating operations increase the potential for exposure.
C. Store away from oxidizing materials.
D. Employers shall advise employees of all areas and operations where exposure to MDA could occur.
VII. Housekeeping and Hygiene Facilities
A. The workplace should be kept clean, orderly, and in a sanitary condition.
The employer should institute a leak and spill detection program for operations involving MDA in order to detect sources of fugitive MDA emissions.
B. Adequate washing facilities with hot and cold water are to be provided and maintained in a sanitary condition. Suitable cleansing agents should also be provided to assure the effective removal of MDA from the skin.
VIII. Common Operations
Common operations in which exposure to MDA is likely to occur include the following: Manufacture of MDA; Manufacture of Methylene diisocyanate; Curing agent for epoxy resin structures; Wire coating operations; and filament winding.
Appendix C to § 1910.1050—Medical Surveillance Guidelines for MDA
I. Route of Entry
Inhalation; skin absorption; ingestion. MDA can be inhaled, absorbed through the skin, or ingested.
II. Toxicology
MDA is a suspect carcinogen in humans. There are several reports of liver disease in humans and animals resulting from acute exposure to MDA. A well documented case of an acute cardiomyopathy secondary to exposure to MDA is on record. Numerous human cases of hepatitis secondary to MDA are known. Upon direct contact MDA may also cause damage to the eyes. Dermatitis and skin sensitization have been observed. Almost all forms of acute environmental hepatic injury in humans involve the hepatic parenchyma and produce hepatocellular jaundice. This agent produces intrahepatic cholestasis. The clinical picture consists of cholestatic jaundice, preceded or accompanied by abdominal pain, fever, and chills. Onset in about 60% of all observed cases is abrupt with severe abdominal pain. In about 30% of observed cases, the illness presented and evolved more slowly and less dramatically, with only slight abdominal pain. In about 10% of the cases only jaundice was evident. The cholestatic nature of the jaundice is evident in the prominence of itching, the histologic predominance of bile stasis, and portal inflammatory infiltration, accompanied by only slight parenchymal injury in most cases, and by the moderately elevated transaminase values. Acute, high doses, however, have been known to cause hepatocellular damage resulting in elevated SGPT, SGOT, alkaline phosphatase and bilirubin.
Absorption through the skin is rapid. MDA is metabolized and excreted over a 48-hour period. Direct contact may be irritating to the skin, causing dermatitis. Also MDA which is deposited on the skin is not thoroughly removed through washing.
MDA may cause bladder cancer in humans. Animal data supporting this assumption is not available nor is conclusive human data. However, human data collected on workers at a helicopter manufacturing facility where MDA is used suggests a higher incidence of bladder cancer among exposed workers.
III. Signs and Symptoms
Skin may become yellow from contact with MDA.
Repeated or prolonged contact with MDA may result in recurring dermatitis (red-itchy, cracked skin) and eye irritation. Inhalation, ingestion or absorption through the skin at high concentrations may result in hepatitis, causing symptoms such as fever and chills, nausea and vomiting, dark urine, anorexia, rash, right upper quadrant pain and jaundice. Corneal burns may occur when MDA is splashed in the eyes.
IV. Treatment of Acute Toxic Effects/Emergency Situation
If MDA gets into the eyes, immediately wash eyes with large amounts of water. If MDA is splashed on the skin, immediately wash contaminated skin with mild soap or detergent. Employee should be removed from exposure and given proper medical treatment. Medical tests required under the emergency section of the medical surveillance section (M)(4) must be conducted.
If the chemical is swallowed do not induce vomiting but remove by gastric lavage.
Appendix D to § 1910.1050—Sampling and Analytical Methods for MDA Monitoring and Measurement Procedures
Measurements taken for the purpose of determining employee exposure to MDA are best taken so that the representative average 8-hour exposure may be determined from a single 8-hour sample or two (2) 4-hour samples. Short-time interval samples (or grab samples) may also be used to determine average exposure level if a minimum of five measurements are taken in a random manner over the 8-hour work shift. Random sampling means that any portion of the work shift has the same chance of being sampled as any other. The arithmetic average of all such random samples taken on one work shift is an estimate of an employee's average level of exposure for that work shift. Air samples should be taken in the employee's breathing zone (air that would most nearly represent that inhaled by the employee).
There are a number of methods available for monitoring employee exposures to MDA. The method OSHA currently uses is included below.
The employer, however, has the obligation of selecting any monitoring method which meets the accuracy and precision requirements of the standard under his unique field conditions. The standard requires that the method of monitoring must have an accuracy, to a 95 percent confidence level, of not less than plus or minus 25 percent for the select PEL.
OSHA Methodology
Sampling Procedure
Apparatus
Samples are collected by use of a personal sampling pump that can be calibrated within ±5% of the recommended flow rate with the sampling filter in line.
Samples are collected on 37 mm Gelman type A/E glass fiber filters treated with sulfuric acid. The filters are prepared by soaking each filter with 0.5 mL of 0.26N H 2 SO 4. (0.26 N H 2 SO 4 can be prepared by diluting 1.5 mL of 36N H 2 SO 4 to 200 mL with deionized water.) The filters are dried in an oven at 100 degrees C for one hour and then assembled into two-piece 37 mm polystyrene cassettes with backup pads. The cassettes are sealed with shrink bands and the ends are plugged with plastic plugs.
After sampling, the filters are carefully removed from the cassettes and individually transferred to small vials containing approximately 2 mL deionized water. The vials must be tightly sealed. The water can be added before or after the filters are transferred. The vials must be sealable and capable of holding at least 7 mL of liquid. Small glass scintillation vials with caps containing Teflon liners are recommended.
Reagents
Deionized water is needed for addition to the vials.
Sampling Technique
Immediately before sampling, remove the plastic plugs from the filter cassettes.
Attach the cassette to the sampling pump with flexible tubing and place the cassette in the employee's breathing zone.
After sampling, seal the cassettes with plastic plugs until the filters are transferred to the vials containing deionized water.
At some convenient time within 10 hours of sampling, transfer the sample filters to vials.
Seal the small vials lengthwise.
Submit at least one blank filter with each sample set. Blanks should be handled in the same manner as samples, but no air is drawn through them.
Record sample volumes (in L of air) for each sample, along with any potential interferences.
Retention Efficiency
A retention efficiency study was performed by drawing 100 L of air (80% relative humidity) at 1 L/min through sample filters that had been spiked with 0.814 µg MDA. Instead of using backup pads, blank acid-treated filters were used as backups in each cassette. Upon analysis, the top filters were found to have an average of 91.8% of the spiked amount. There was no MDA found on the bottom filters, so the amount lost was probably due to the slight instability of the MDA salt.
Extraction Efficiency
The average extraction efficiency for six filters spiked at the target concentration is 99.6%.
The stability of extracted and derivatized samples was verified by reanalyzing the above six samples the next day using fresh standards. The average extraction efficiency for the reanalyzed samples is 98.7%.
Recommended Air Volume and Sampling Rate
The recommended air volume is 100 L.
The recommended sampling rate is 1 L/min.
Interferences (Sampling)
MDI appears to be a positive interference. It was found that when MDI was spiked onto an acid-treated filter, the MDI converted to MDA after air was drawn through it.
Suspected interferences should be reported to the laboratory with submitted samples.
Safety Precautions (Sampling)
Attach the sampling equipment to the employees so that it will not interfere with work performance or safety.
Follow all safety procedures that apply to the work area being sampled.
Analytical Procedure
Apparatus: The following are required for analysis.
A GC equipped with an electron capture detector. For this evaluation a Tracor 222 Gas Chromatograph equipped with a Nickel 63 High Temperature Electron Capture Detector and a Linearizer was used.
A GC column capable of separating the MDA derivative from the solvent and interferences. A 6 ft × 2 mm ID glass column packed with 3% OV-101 coated on 100/120 Gas Chrom Q was used in this evaluation.
A electronic integrator or some other suitable means of measuring peak areas or heights.
Small resealable vials with Teflon-lined caps capable of holding 4 mL.
A dispenser or pipet for toluene capable of delivering 2.0 mL.
Pipets (or repipets with plastic or Teflon tips) capable of delivering 1 mL for the sodium hydroxide and buffer solutions.
A repipet capable of delivering 25 µL HFAA.
Syringes for preparation of standards and injection of standards and samples into a GC.
Volumetric flasks and pipets to dilute the pure MDA in preparation of standards.
Disposable pipets to transfer the toluene layers after the samples are extracted.
Reagents
0.5 NaOH prepared from reagent grade NaOH.
Toluene, pesticide grade. Burdick and Jackson distilled in glass toluene was used.
Heptafluorobutyric acid anhydride (HFAA). HFAA from Pierce Chemical Company was used.
pH 7.0 phosphate buffer, prepared from 136 g potassium dihydrogen phosphate and 1 L deionized water. The pH is adjusted to 7.0 with saturated sodium hydroxide solution.
4,4′ -Methylenedianiline (MDA), reagent grade.
Standard Preparation
Concentrated stock standards are prepared by diluting pure MDA with toluene. Analytical standards are prepared by injecting uL amounts of diluted stock standards into vials that contain 2.0 mL toluene.
25 uL HFAA are added to each vial and the vials are capped and shaken for 10 seconds.
After 10 min, 1 mL of buffer is added to each vial.
The vials are recapped and shaken for 10 seconds.
After allowing the layers to separate, aliquots of the toluene (upper) layers are removed with a syringe and analyzed by GC.
Analytical standard concentrations should bracket sample concentrations. Thus, if samples fall out of the range of prepared standards, additional standards must be prepared to ascertain detector response.
Sample Preparation
The sample filters are received in vials containing deionized water.
1 mL of 0.5N NaOH and 2.0 mL toluene are added to each vial.
The vials are recapped and shaken for 10 min.
After allowing the layers to separate, approximately 1 mL aliquots of the toluene (upper) layers are transferred to separate vials with clean disposable pipets.
The toluene layers are treated and analyzed.
Analysis
GC conditions
Zone temperatures:
Column—220 degrees C
Injector—235 degrees C
Detector—335 degrees C
4
[57 FR 35666, Aug. 10, 1992, as amended at 57 FR 49649, Nov. 3, 1992; 61 FR 5508, Feb. 13, 1996; 63 FR 1293, Jan. 8, 1998; 67 FR 67965, Nov. 7, 2002; 71 FR 16672, 16673, Apr. 3, 2006; 71 FR 50190, Aug. 24, 2006; 73 FR 75586, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR 17785, Mar. 26, 2012]
Injection volume: 5.0 uL
1/8
Retention time of MDA derivative: 3.5 min
Chromatogram
Peak areas or heights are measured by an integrator or other suitable means.
A calibration curve is constructed by plotting response (peak areas or heights) of standard injections versus ug of MDA per sample. Sample concentrations must be bracketed by standards.
Interferences (Analytical)
Any compound that gives an electron capture detector response and has the same general retention time as the HFAA derivative of MDA is a potential interference. Suspected interferences reported to the laboratory with submitted samples by the industrial hygienist must be considered before samples are derivatized.
GC parameters may be changed to possibly circumvent interferences.
Retention time on a single column is not considered proof of chemical identity. Analyte identity should be confirmed by GC/MS if possible.
Calculations
The analyte concentration for samples is obtained from the calibration curve in terms of ug MDA per sample. The extraction efficiency is 100%. If any MDA is found on the blank, that amount is subtracted from the sample amounts. The air concentrations are calculated using the following formulae.
3
3
3
Safety Precautions (Analytical)
Avoid skin contact and inhalation of all chemicals.
Restrict the use of all chemicals to a fume hood if possible.
Wear safety glasses and a lab coat at all times while in the lab area.
For the purpose of this section, the following definitions shall apply:
Action level means a concentration of airborne BD of 0.5 ppm calculated as an eight (8)-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically designated by the employer, whose duties require entrance into a regulated area, or a person entering such an area as a designated representative of employees to exercise the right to observe monitoring and measuring procedures under paragraph (d)(8) of this section, or a person designated under the Act or regulations issued under the Act to enter a regulated area.
1,3-Butadiene means an organic compound with chemical formula CH 2 = CH-CH = CH 2 that has a molecular weight of approximately 54.15 gm/mole.
Business day means any Monday through Friday, except those days designated as federal, state, local or company specific holidays.
Complete Blood Count (CBC) means laboratory tests performed on whole blood specimens and includes the following: White blood cell count (WBC), hematocrit (Hct), red blood cell count (RBC), hemoglobin (Hgb), differential count of white blood cells, red blood cell morphology, red blood cell indices, and platelet count.
Day means any part of a calendar day.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Emergency situation means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment that may or does result in an uncontrolled significant release of BD.
Employee exposure means exposure of a worker to airborne concentrations of BD which would occur if the employee were not using respiratory protective equipment.
Objective data means monitoring data, or mathematical modelling or calculations based on composition, chemical and physical properties of a material, stream or product.
Permissible Exposure Limits, PELs means either the 8 hour Time Weighted Average (8-hr TWA) exposure or the Short-Term Exposure Limit (STEL).
Physician or other licensed health care professional is an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide one or more of the specific health care services required by paragraph (k) of this section.
Regulated area means any area where airborne concentrations of BD exceed or can reasonably be expected to exceed the 8-hour time weighted average (8-hr TWA) exposure of 1 ppm or the short-term exposure limit (STEL) of 5 ppm for 15 minutes.
This section means this 1,3-butadiene standard.
The employer shall ensure that no employee is exposed to an airborne concentration of BD in excess of one (1) part BD per million parts of air (ppm) measured as an eight (8)-hour time-weighted average.
The employer shall ensure that no employee is exposed to an airborne concentration of BD in excess of five parts of BD per million parts of air (5 ppm) as determined over a sampling period of fifteen (15) minutes.
Monitoring shall be accurate, at a confidence level of 95 percent, to within plus or minus 25 percent for airborne concentrations of BD at or above the 1 ppm TWA limit and to within plus or minus 35 percent for airborne concentrations of BD at or above the action level of 0.5 ppm and below the 1 ppm TWA limit.
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to BD conducted in accordance with paragraph (d) of this section.
When observation of the monitoring of employee exposure to BD requires entry into an area where the use of protective clothing or equipment is required, the employer shall provide the observer at no cost with protective clothing and equipment, and shall ensure that the observer uses this equipment and complies with all other applicable safety and health procedures.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
| Concentration of airborne BD (ppm) or condition of use | Minimum required respirator |
|---|---|
| Less than or equal to 5 ppm (5 times PEL) | (a) Air-purifying half mask or full facepiece respirator equipped with approved BD or organic vapor cartridges or canisters. Cartridges or canisters shall be replaced every 4 hours. |
| Less than or equal to 10 ppm (10 times PEL) | (a) Air-purifying half mask or full facepiece respirator equipped with approved BD or organic vapor cartridges or canisters. Cartridges or canisters shall be replaced every 3 hours. |
| Less than or equal to 25 ppm (25 times PEL) | (a) Air-purifying full facepiece respirator equipped with approved BD or organic vapor cartridges or canisters. Cartridges or canisters shall be replaced every 2 hours. |
| (b) Any powered air-purifying respirator equipped with approved BD or organic vapor cartridges. PAPR cartridges shall be replaced every 2 hours. | |
| (c) Continuous flow supplied air respirator equipped with a hood or helmet. | |
| Less than or equal to 50 ppm (50 times PEL) | (a) Air-purifying full facepiece respirator equipped with approved BD or organic vapor cartridges or canisters. Cartridges or canisters shall be replaced every (1) hour. |
| (b) Powered air-purifying respirator equipped with a tight-fitting facepiece and an approved BD or organic vapor cartridges. PAPR cartridges shall be replaced every (1) hour. | |
| Less than or equal to 1,000 ppm (1,000 times PEL) | (a) Supplied air respirator equipped with a half mask of full facepiece and operated in a pressure demand or other positive pressure mode. |
| Greater than 1000 ppm unknown concentration, or firefighting | (a) Self-contained breathing apparatus equipped with a full facepiece and operated in a pressure demand or other positive pressure mode. |
| (b) Any supplied air respirator equipped with a full facepiece and operated in a pressure demand or other positive pressure mode in combination with an auxiliary self-contained breathing apparatus operated in a pressure demand or other positive pressure mode. | |
| Escape from IDLH conditions | (a) Any positive pressure self-contained breathing apparatus with an appropriate service life. |
| (b) A air-purifying full facepiece respirator equipped with a front or back mounted BD or organic vapor canister. | |
| Notes: Respirators approved for use in higher concentrations are permitted to be used in lower concentrations. Full facepiece is required when eye irritation is anticipated. |
Where appropriate to prevent eye contact and limit dermal exposure to BD, the employer shall provide protective clothing and equipment at no cost to the employee and shall ensure its use. Eye and face protection shall meet the requirements of 29 CFR 1910.133.
Written plan. A written plan for emergency situations shall be developed, or an existing plan shall be modified, to contain the applicable elements specified in 29 CFR 1910.38 and 29 CFR 1910.39, “Emergency action plans” and “Fire prevention plans,” respectively, and in 29 CFR 1910.120, “Hazardous Waste Operations and Emergency Response,” for each workplace where there is the possibility of an emergency.
The employer shall institute a medical screening and surveillance program as specified in this paragraph for:
The employer shall make medical screening available on the following schedule:
The employer shall transfer medical and exposure records as set forth in 29 CFR 1910.1020(h).
Appendix A to § 1910.1051—Substance Safety Data Sheet For 1,3-Butadiene (Non-Mandatory)
I. Substance Identification
A. Substance: 1,3-Butadiene (CH 2 = CH-CH = CH 2 ).
B. Synonyms: 1,3-Butadiene (BD); butadiene; biethylene; bi-vinyl; divinyl; butadiene-1,3; buta-1,3-diene; erythrene; NCI-C50602; CAS-106-99-0.
C. BD can be found as a gas or liquid.
D. BD is used in production of styrene-butadiene rubber and polybutadiene rubber for the tire industry. Other uses include copolymer latexes for carpet backing and paper coating, as well as resins and polymers for pipes and automobile and appliance parts. It is also used as an intermediate in the production of such chemicals as fungicides.
E. Appearance and odor: BD is a colorless, non-corrosive, flammable gas with a mild aromatic odor at standard ambient temperature and pressure.
F. Permissible exposure: Exposure may not exceed 1 part BD per million parts of air averaged over the 8-hour workday, nor may short-term exposure exceed 5 parts of BD per million parts of air averaged over any 15-minute period in the 8-hour workday.
II. Health Hazard Data
A. BD can affect the body if the gas is inhaled or if the liquid form, which is very cold (cryogenic), comes in contact with the eyes or skin.
B. Effects of overexposure: Breathing very high levels of BD for a short time can cause central nervous system effects, blurred vision, nausea, fatigue, headache, decreased blood pressure and pulse rate, and unconsciousness. There are no recorded cases of accidental exposures at high levels that have caused death in humans, but this could occur. Breathing lower levels of BD may cause irritation of the eyes, nose, and throat. Skin contact with liquefied BD can cause irritation and frostbite.
C. Long-term (chronic) exposure: BD has been found to be a potent carcinogen in rodents, inducing neoplastic lesions at multiple target sites in mice and rats. A recent study of BD-exposed workers showed that exposed workers have an increased risk of developing leukemia. The risk of leukemia increases with increased exposure to BD. OSHA has concluded that there is strong evidence that workplace exposure to BD poses an increased risk of death from cancers of the lymphohematopoietic system.
D. Reporting signs and symptoms: You should inform your supervisor if you develop any of these signs or symptoms and suspect that they are caused by exposure to BD.
III. Emergency First Aid Procedures
In the event of an emergency, follow the emergency plan and procedures designated for your work area. If you have been trained in first aid procedures, provide the necessary first aid measures. If necessary, call for additional assistance from co-workers and emergency medical personnel.
A. Eye and Skin Exposures: If there is a potential that liquefied BD can come in contact with eye or skin, face shields and skin protective equipment must be provided and used. If liquefied BD comes in contact with the eye, immediately flush the eyes with large amounts of water, occasionally lifting the lower and the upper lids. Flush repeatedly. Get medical attention immediately. Contact lenses should not be worn when working with this chemical. In the event of skin contact, which can cause frostbite, remove any contaminated clothing and flush the affected area repeatedly with large amounts of tepid water.
B. Breathing: If a person breathes in large amounts of BD, move the exposed person to fresh air at once. If breathing has stopped, begin cardiopulmonary resuscitation (CPR) if you have been trained in this procedure. Keep the affected person warm and at rest. Get medical attention immediately.
C. Rescue: Move the affected person from the hazardous exposure. If the exposed person has been overcome, call for help and begin emergency rescue procedures. Use extreme caution so that you do not become a casualty. Understand the plant's emergency rescue procedures and know the locations of rescue equipment before the need arises.
IV. Respirators and Protective Clothing
A. Respirators: Good industrial hygiene practices recommend that engineering and work practice controls be used to reduce environmental concentrations to the permissible exposure level. However, there are some exceptions where respirators may be used to control exposure. Respirators may be used when engineering and work practice controls are not technically feasible, when such controls are in the process of being installed, or when these controls fail and need to be supplemented or during brief, non-routine, intermittent exposure. Respirators may also be used in situations involving non-routine work operations which are performed infrequently and in which exposures are limited in duration, and in emergency situations. In some instances cartridge respirator use is allowed, but only with strict time constraints. For example, at exposure below 5 ppm BD, a cartridge (or canister) respirator, either full or half face, may be used, but the cartridge must be replaced at least every 4 hours, and it must be replaced every 3 hours when the exposure is between 5 and 10 ppm. If the use of respirators is necessary, the only respirators permitted are those that have been approved by the National Institute for Occupational Safety and Health (NIOSH). In addition to respirator selection, a complete respiratory protection program must be instituted which includes regular training, maintenance, fit testing, inspection, cleaning, and evaluation of respirators. If you can smell BD while wearing a respirator, proceed immediately to fresh air, and change cartridge (or canister) before re-entering an area where there is BD exposure. If you experience difficulty in breathing while wearing a respirator, tell your supervisor.
B. Protective Clothing: Employees should be provided with and required to use impervious clothing, gloves, face shields (eight-inch minimum), and other appropriate protective clothing necessary to prevent the skin from becoming frozen by contact with liquefied BD (or a vessel containing liquid BD).
Employees should be provided with and required to use splash-proof safety goggles where liquefied BD may contact the eyes.
V. Precautions for Safe Use, Handling, and Storage
A. Fire and Explosion Hazards: BD is a flammable gas and can easily form explosive mixtures in air. It has a lower explosive limit of 2%, and an upper explosive limit of 11.5%. It has an autoignition temperature of 420 °C (788 °F). Its vapor is heavier than air (vapor density, 1.9) and may travel a considerable distance to a source of ignition and flash back. Usually it contains inhibitors to prevent self-polymerization (which is accompanied by evolution of heat) and to prevent formation of explosive peroxides. At elevated temperatures, such as in fire conditions, polymerization may take place. If the polymerization takes place in a container, there is a possibility of violent rupture of the container.
B. Hazard: Slightly toxic. Slight respiratory irritant. Direct contact of liquefied BD on skin may cause freeze burns and frostbite.
C. Storage: Protect against physical damage to BD containers. Outside or detached storage of BD containers is preferred. Inside storage should be in a cool, dry, well-ventilated, noncombustible location, away from all possible sources of ignition. Store cylinders vertically and do not stack. Do not store with oxidizing material.
D. Usual Shipping Containers: Liquefied BD is contained in steel pressure apparatus.
E. Electrical Equipment: Electrical installations in Class I hazardous locations, as defined in Article 500 of the National Electrical Code, should be in accordance with Article 501 of the Code. If explosion-proof electrical equipment is necessary, it shall be suitable for use in Group B. Group D equipment may be used if such equipment is isolated in accordance with Section 501-5(a) by sealing all conduit 1/2 - inch size or larger. See Venting of Deflagrations (NFPA No. 68, 1994), National Electrical Code (NFPA No. 70, 1996), Static Electricity (NFPA No. 77, 1993), Lightning Protection Systems (NFPA No. 780, 1995), and Fire Hazard Properties of Flammable Liquids, Gases and Volatile Solids (NFPA No. 325, 1994).
F. Fire Fighting: Stop flow of gas. Use water to keep fire-exposed containers cool. Fire extinguishers and quick drenching facilities must be readily available, and you should know where they are and how to operate them.
G. Spill and Leak: Persons not wearing protective equipment and clothing should be restricted from areas of spills or leaks until clean-up has been completed. If BD is spilled or leaked, the following steps should be taken:
1. Eliminate all ignition sources.
2. Ventilate area of spill or leak.
3. If in liquid form, for small quantities, allow to evaporate in a safe manner.
4. Stop or control the leak if this can be done without risk. If source of leak is a cylinder and the leak cannot be stopped in place, remove the leaking cylinder to a safe place and repair the leak or allow the cylinder to empty.
H. Disposal: This substance, when discarded or disposed of, is a hazardous waste according to Federal regulations (40 CFR part 261). It is listed as hazardous waste number D001 due to its ignitability. The transportation, storage, treatment, and disposal of this waste material must be conducted in compliance with 40 CFR parts 262, 263, 264, 268 and 270. Disposal can occur only in properly permitted facilities. Check state and local regulation of any additional requirements as these may be more restrictive than federal laws and regulation.
I. You should not keep food, beverages, or smoking materials in areas where there is BD exposure, nor should you eat or drink in such areas.
J. Ask your supervisor where BD is used in your work area and ask for any additional plant safety and health rules.
VI. Medical Requirements
Your employer is required to offer you the opportunity to participate in a medical screening and surveillance program if you are exposed to BD at concentrations exceeding the action level (0.5 ppm BD as an 8-hour TWA) on 30 days or more a year, or at or above the 8 hr TWA (1 ppm) or STEL (5 ppm for 15 minutes) on 10 days or more a year. Exposure for any part of a day counts. If you have had exposure to BD in the past, but have been transferred to another job, you may still be eligible to participate in the medical screening and surveillance program. The OSHA rule specifies the past exposures that would qualify you for participation in the program. These past exposure are work histories that suggest the following: (1) That you have been exposed at or above the PELs on 30 days a year for 10 or more years; (2) that you have been exposed at or above the action level on 60 days a year for 10 or more years; or (3) that you have been exposed above 10 ppm on 30 days in any past year. Additionally, if you are exposed to BD in an emergency situation, you are eligible for a medical examination within 48 hours. The basic medical screening program includes a health questionnaire, physical examination, and blood test. These medical evaluations must be offered to you at a reasonable time and place, and without cost or loss of pay.
VII. Observation of Monitoring
Your employer is required to perform measurements that are representative of your exposure to BD and you or your designated representative are entitled to observe the monitoring procedure. You are entitled to observe the steps taken in the measurement procedure, and to record the results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and equipment are required to be worn, you or your representative must also be provided with, and must wear, the protective clothing and equipment.
VIII. Access to Information
A. Each year, your employer is required to inform you of the information contained in this appendix. In addition, your employer must instruct you in the proper work practices for using BD, emergency procedures, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being exposed to BD. You or your representative has the right to observe employee measurements and to record the results obtained. Your employer is required to inform you of your exposure. If your employer determines that you are being overexposed, he or she is required to inform you of the actions which are being taken to reduce your exposure to within permissible exposure limits and of the schedule to implement these actions.
C. Your employer is required to keep records of your exposures and medical examinations. These records must be kept by the employer for at least thirty (30) years.
D. Your employer is required to release your exposure and medical records to you or your representative upon your request.
Appendix B to § 1910.1051—Substance Technical Guidelines for 1,3-Butadiene (Non-Mandatory)
I. Physical and Chemical Data
A. Substance identification:
1. Synonyms: 1,3-Butadiene (BD); butadiene; biethylene; bivinyl; divinyl; butadiene-1,3; buta-1,3-diene; erythrene; NCI-C50620; CAS-106-99-0.
2. Formula: CH 2 = CH-CH = CH 2.
3. Molecular weight: 54.1.
B. Physical data:
1. Boiling point (760 mm Hg): −4.7 °C (23.5 °F).
2. Specific gravity (water = 1): 0.62 at 20 °C (68 °F).
3. Vapor density (air = 1 at boiling point of BD): 1.87.
4. Vapor pressure at 20 °C (68 °F): 910 mm Hg.
5. Solubility in water, g/100 g water at 20 °C (68 °F): 0.05.
6. Appearance and odor: Colorless, flammable gas with a mildly aromatic odor. Liquefied BD is a colorless liquid with a mildly aromatic odor.
II. Fire, Explosion, and Reactivity Hazard Data
A. Fire:
1. Flash point: −76 °C (−105 °F) for take out; liquefied BD; Not applicable to BD gas.
2. Stability: A stabilizer is added to the monomer to inhibit formation of polymer during storage. Forms explosive peroxides in air in absence of inhibitor.
3. Flammable limits in air, percent by volume: Lower: 2.0; Upper: 11.5.
4. Extinguishing media: Carbon dioxide for small fires, polymer or alcohol foams for large fires.
5. Special fire fighting procedures: Fight fire from protected location or maximum possible distance. Stop flow of gas before extinguishing fire. Use water spray to keep fire-exposed cylinders cool.
6. Unusual fire and explosion hazards: BD vapors are heavier than air and may travel to a source of ignition and flash back. Closed containers may rupture violently when heated.
7. For purposes of compliance with the requirements of 29 CFR 1910.106, BD is classified as a flammable gas. For example, 7,500 ppm, approximately one-fourth of the lower flammable limit, would be considered to pose a potential fire and explosion hazard.
8. For purposes of compliance with 29 CFR 1910.155, BD is classified as a Class B fire hazard.
9. For purposes of compliance with 29 CFR 1910.307, locations classified as hazardous due to the presence of BD shall be Class I.
B. Reactivity:
1. Conditions contributing to instability: Heat. Peroxides are formed when inhibitor concentration is not maintained at proper level. At elevated temperatures, such as in fire conditions, polymerization may take place.
2. Incompatibilities: Contact with strong oxidizing agents may cause fires and explosions. The contacting of crude BD (not BD monomer) with copper and copper alloys may cause formations of explosive copper compounds.
3. Hazardous decomposition products: Toxic gases (such as carbon monoxide) may be released in a fire involving BD.
4. Special precautions: BD will attack some forms of plastics, rubber, and coatings. BD in storage should be checked for proper inhibitor content, for self-polymerization, and for formation of peroxides when in contact with air and iron. Piping carrying BD may become plugged by formation of rubbery polymer.
C. Warning Properties:
1. Odor Threshold: An odor threshold of 0.45 ppm has been reported in The American Industrial Hygiene Association (AIHA) Report, Odor Thresholds for Chemicals with Established Occupational Health Standards. (Ex. 32-28C)
2. Eye Irritation Level: Workers exposed to vapors of BD (concentration or purity unspecified) have complained of irritation of eyes, nasal passages, throat, and lungs. Dogs and rabbits exposed experimentally to as much as 6700 ppm for 7 1/2 hours a day for 8 months have developed no histologically demonstrable abnormality of the eyes.
3. Evaluation of Warning Properties: Since the mean odor threshold is about half of the 1 ppm PEL, and more than 10-fold below the 5 ppm STEL, most wearers of air purifying respirators should still be able to detect breakthrough before a significant overexposure to BD occurs.
III. Spill, Leak, and Disposal Procedures
A. Persons not wearing protective equipment and clothing should be restricted from areas of spills or leaks until cleanup has been completed. If BD is spilled or leaked, the following steps should be taken:
1. Eliminate all ignition sources.
2. Ventilate areas of spill or leak.
3. If in liquid form, for small quantities, allow to evaporate in a safe manner.
4. Stop or control the leak if this can be done without risk. If source of leak is a cylinder and the leak cannot be stopped in place, remove the leaking cylinder to a safe place and repair the leak or allow the cylinder to empty.
B. Disposal: This substance, when discarded or disposed of, is a hazardous waste according to Federal regulations (40 CFR part 261). It is listed by the EPA as hazardous waste number D001 due to its ignitability. The transportation, storage, treatment, and disposal of this waste material must be conducted in compliance with 40 CFR parts 262, 263, 264, 268 and 270. Disposal can occur only in properly permitted facilities. Check state and local regulations for any additional requirements because these may be more restrictive than federal laws and regulations.
IV. Monitoring and Measurement Procedures
A. Exposure above the Permissible Exposure Limit (8-hr TWA) or Short-Term Exposure Limit (STEL):
1. 8-hr TWA exposure evaluation: Measurements taken for the purpose of determining employee exposure under this standard are best taken with consecutive samples covering the full shift. Air samples must be taken in the employee's breathing zone (air that would most nearly represent that inhaled by the employee).
2. STEL exposure evaluation: Measurements must represent 15 minute exposures associated with operations most likely to exceed the STEL in each job and on each shift.
3. Monitoring frequencies: Table 1 gives various exposure scenarios and their required monitoring frequencies, as required by the final standard for occupational exposure to butadiene.
| Action level | 8-hr TWA | STEL | Required monitoring activity |
|---|---|---|---|
| −* | − | − | No 8-hr TWA or STEL monitoring required. |
| + * | − | − | No STEL monitoring required. Monitor 8-hr TWA annually. |
| + | + | − | No STEL monitoring required. Periodic monitoring 8-hr TWA, in accordance with (d)(3)(ii).** |
| + | + | + | Periodic monitoring 8-hr TWA, in accordance with (d)(3)(ii)**. Periodic monitoring STEL, in accordance with (d)(3)(iii). |
| + | − | + | Periodic monitoring STEL, in accordance with (d)(3)(iii). Monitor 8-hr TWA, annually. |
| * Exposure Scenario, Limit Exceeded: + = Yes, −= No. | |||
| ** The employer may decrease the frequency of exposure monitoring to annually when at least 2 consecutive measurements taken at least 7 days apart show exposures to be below the 8 hr TWA, but at or above the action level. |
4. Monitoring techniques: appendix D describes the validated method of sampling and analysis which has been tested by OSHA for use with BD. The employer has the obligation of selecting a monitoring method which meets the accuracy and precision requirements of the standard under his or her unique field conditions. The standard requires that the method of monitoring must be accurate, to a 95 percent confidence level, to plus or minus 25 percent for concentrations of BD at or above 1 ppm, and to plus or minus 35 percent for concentrations below 1 ppm.
V. Personal Protective Equipment
A. Employees should be provided with and required to use impervious clothing, gloves, face shields (eight-inch minimum), and other appropriate protective clothing necessary to prevent the skin from becoming frozen from contact with liquid BD.
B. Any clothing which becomes wet with liquid BD should be removed immediately and not re-worn until the butadiene has evaporated.
C. Employees should be provided with and required to use splash proof safety goggles where liquid BD may contact the eyes.
VI. Housekeeping and Hygiene Facilities
For purposes of complying with 29 CFR 1910.141, the following items should be emphasized:
A. The workplace should be kept clean, orderly, and in a sanitary condition.
B. Adequate washing facilities with hot and cold water are to be provided and maintained in a sanitary condition.
VII. Additional Precautions
A. Store BD in tightly closed containers in a cool, well-ventilated area and take all necessary precautions to avoid any explosion hazard.
B. Non-sparking tools must be used to open and close metal containers. These containers must be effectively grounded.
C. Do not incinerate BD cartridges, tanks or other containers.
D. Employers must advise employees of all areas and operations where exposure to BD might occur.
Appendix C to § 1910.1051—Medical Screening and Surveillance for 1,3-Butadiene (Non-Mandatory)
I. Basis for Medical Screening and Surveillance Requirements
A. Route of Entry Inhalation
B. Toxicology
Inhalation of BD has been linked to an increased risk of cancer, damage to the reproductive organs, and fetotoxicity. Butadiene can be converted via oxidation to epoxybutene and diepoxybutane, two genotoxic metabolites that may play a role in the expression of BD's toxic effects.
BD has been tested for carcinogenicity in mice and rats. Both species responded to BD exposure by developing cancer at multiple primary organ sites. Early deaths in mice were caused by malignant lymphomas, primarily lymphocytic type, originating in the thymus.
Mice exposed to BD have developed ovarian or testicular atrophy. Sperm head morphology tests also revealed abnormal sperm in mice exposed to BD; lethal mutations were found in a dominant lethal test. In light of these results in animals, the possibility that BD may adversely affect the reproductive systems of male and female workers must be considered.
Additionally, anemia has been observed in animals exposed to butadiene. In some cases, this anemia appeared to be a primary response to exposure; in other cases, it may have been secondary to a neoplastic response.
C. Epidemiology
Epidemiologic evidence demonstrates that BD exposure poses an increased risk of leukemia. Mild alterations of hematologic parameters have also been observed in synthetic rubber workers exposed to BD.
II. Potential Adverse Health Effects
A. Acute
Skin contact with liquid BD causes characteristic burns or frostbite. BD is gaseous form can irritate the eyes, nasal passages, throat, and lungs. Blurred vision, coughing, and drowsiness may also occur. Effects are mild at 2,000 ppm and pronounced at 8,000 ppm for exposures occurring over the full workshift.
At very high concentrations in air, BD is an anesthetic, causing narcosis, respiratory paralysis, unconsciousness, and death. Such concentrations are unlikely, however, except in an extreme emergency because BD poses an explosion hazard at these levels.
B. Chronic
The principal adverse health effects of concern are BD-induced lymphoma, leukemia and potential reproductive toxicity. Anemia and other changes in the peripheral blood cells may be indicators of excessive exposure to BD.
C. Reproductive
Workers may be concerned about the possibility that their BD exposure may be affecting their ability to procreate a healthy child. For workers with high exposures to BD, especially those who have experienced difficulties in conceiving, miscarriages, or stillbirths, appropriate medical and laboratory evaluation of fertility may be necessary to determine if BD is having any adverse effect on the reproductive system or on the health of the fetus.
III. Medical Screening Components At-A-Glance
A. Health Questionnaire
The most important goal of the health questionnaire is to elicit information from the worker regarding potential signs or symptoms generally related to leukemia or other blood abnormalities. Therefore, physicians or other licensed health care professionals should be aware of the presenting symptoms and signs of lymphohematopoietic disorders and cancers, as well as the procedures necessary to confirm or exclude such diagnoses. Additionally, the health questionnaire will assist with the identification of workers at greatest risk of developing leukemia or adverse reproductive effects from their exposures to BD.
Workers with a history of reproductive difficulties or a personal or family history of immune deficiency syndromes, blood dyscrasias, lymphoma, or leukemia, and those who are or have been exposed to medicinal drugs or chemicals known to affect the hematopoietic or lymphatic systems may be at higher risk from their exposure to BD. After the initial administration, the health questionnaire must be updated annually.
B. Complete Blood Count (CBC)
The medical screening and surveillance program requires an annual CBC, with differential and platelet count, to be provided for each employee with BD exposure. This test is to be performed on a blood sample obtained by phlebotomy of the venous system or, if technically feasible, from a fingerstick sample of capillary blood. The sample is to be analyzed by an accredited laboratory.
Abnormalities in a CBC may be due to a number of different etiologies. The concern for workers exposed to BD includes, but is not limited to, timely identification of lymphohematopoietic cancers, such as leukemia and non-Hodgkin's lymphoma. Abnormalities of portions of the CBC are identified by comparing an individual's results to those of an established range of normal values for males and females. A substantial change in any individual employee's CBC may also be viewed as “abnormal” for that individual even if all measurements fall within the population-based range of normal values. It is suggested that a flowsheet for laboratory values be included in each employee's medical record so that comparisons and trends in annual CBCs can be easily made.
A determination of the clinical significance of an abnormal CBC shall be the responsibility of the examining physician, other licensed health care professional, or medical specialist to whom the employee is referred. Ideally, an abnormal CBC should be compared to previous CBC measurements for the same employee, when available. Clinical common sense may dictate that a CBC value that is very slightly outside the normal range does not warrant medical concern. A CBC abnormality may also be the result of a temporary physical stressor, such as a transient viral illness, blood donation, or menorrhagia, or laboratory error. In these cases, the CBC should be repeated in a timely fashion, i.e., within 6 weeks, to verify that return to the normal range has occurred. A clinically significant abnormal CBC should result in removal of the employee from further exposure to BD. Transfer of the employee to other work duties in a BD-free environment would be the preferred recommendation.
C. Physical Examination
The medical screening and surveillance program requires an initial physical examination for workers exposed to BD; this examination is repeated once every three years. The initial physical examination should assess each worker's baseline general health and rule out clinical signs of medical conditions that may be caused by or aggravated by occupational BD exposure. The physical examination should be directed at identification of signs of lymphohematopoietic disorders, including lymph node enlargement, splenomegaly, and hepatomegaly.
Repeated physical examinations should update objective clinical findings that could be indicative of interim development of a lymphohematopoietic disorder, such as lymphoma, leukemia, or other blood abnormality. Physical examinations may also be provided on an as needed basis in order to follow up on a positive answer on the health questionnaire, or in response to an abnormal CBC. Physical examination of workers who will no longer be working in jobs with BD exposure are intended to rule out lymphohematopoietic disorders.
The need for physical examinations for workers concerned about adverse reproductive effects from their exposure to BD should be identified by the physician or other licensed health care professional and provided accordingly. For these workers, such consultations and examinations may relate to developmental toxicity and reproductive capacity.
Physical examination of workers acutely exposed to significant levels of BD should be especially directed at the respiratory system, eyes, sinuses, skin, nervous system, and any region associated with particular complaints. If the worker has received a severe acute exposure, hospitalization may be required to assure proper medical management. Since this type of exposure may place workers at greater risk of blood abnormalities, a CBC must be obtained within 48 hours and repeated at one, two, and three months.
Appendix D to § 1910.1051—Sampling and Analytical Method for 1,3-Butadiene (Non-Mandatory)
OSHA Method No.: 56.
Matrix: Air.
Target concentration: 1 ppm (2.21 mg/m 3 )
Procedure: Air samples are collected by drawing known volumes of air through sampling tubes containing charcoal adsorbent which has been coated with 4-tert-butylcatechol. The samples are desorbed with carbon disulfide and then analyzed by gas chromatography using a flame ionization detector.
Recommended sampling rate and air volume: 0.05 L/min and 3 L.
Detection limit of the overall procedure: 90 ppb (200 ug/m 3 ) (based on 3 L air volume).
Reliable quantitation limit: 155 ppb (343 ug/m 3 ) (based on 3 L air volume).
Standard error of estimate at the target concentration: 6.5%.
Special requirements: The sampling tubes must be coated with 4-tert-butylcatechol. Collected samples should be stored in a freezer.
Status of method: A sampling and analytical method has been subjected to the established evaluation procedures of the Organic Methods Evaluation Branch, OSHA Analytical Laboratory, Salt Lake City, Utah 84165.
1. Background
This work was undertaken to develop a sampling and analytical procedure for BD at 1 ppm. The current method recommended by OSHA for collecting BD uses activated coconut shell charcoal as the sampling medium (Ref. 5.2). This method was found to be inadequate for use at low BD levels because of sample instability.
The stability of samples has been significantly improved through the use of a specially cleaned charcoal which is coated with 4-tert-butylcatechol (TBC). TBC is a polymerization inhibitor for BD (Ref. 5.3).
1.1.1 Toxic effects
Symptoms of human exposure to BD include irritation of the eyes, nose and throat. It can also cause coughing, drowsiness and fatigue. Dermatitis and frostbite can result from skin exposure to liquid BD. (Ref. 5.1)
NIOSH recommends that BD be handled in the workplace as a potential occupational carcinogen. This recommendation is based on two inhalation studies that resulted in cancers at multiple sites in rats and in mice. BD has also demonstrated mutagenic activity in the presence of a liver microsomal activating system. It has also been reported to have adverse reproductive effects. (Ref. 5.1)
1.1.2. Potential workplace exposure
About 90% of the annual production of BD is used to manufacture styrene-butadiene rubber and Polybutadiene rubber. Other uses include: Polychloroprene rubber, acrylonitrile butadiene-stryene resins, nylon intermediates, styrene-butadiene latexes, butadiene polymers, thermoplastic elastomers, nitrile resins, methyl methacrylate-butadiene styrene resins and chemical intermediates. (Ref. 5.1)
1.1.3. Physical properties (Ref. 5.1)
CAS No.: 106-99-0
Molecular weight: 54.1
Appearance: Colorless gas
Boiling point: −4.41 °C (760 mm Hg)
Freezing point: −108.9 °C
Vapor pressure: 2 atm @ 15.3 °C; 5 atm @ 47 °C
Explosive limits: 2 to 11.5% (by volume in air)
Odor threshold: 0.45 ppm
Structural formula: H 2 C:CHCH:CH 2
Synonyms: BD; biethylene; bivinyl; butadiene; divinyl; buta-1,3-diene; alpha-gamma-butadiene; erythrene; NCI-C50602; pyrrolylene; vinylethylene.
1.2. Limit defining parameters
The analyte air concentrations listed throughout this method are based on an air volume of 3 L and a desorption volume of 1 mL. Air concentrations listed in ppm are referenced to 25 °C and 760 mm Hg.
1.2.1. Detection limit of the analytical procedure
The detection limit of the analytical procedure was 304 pg per injection. This was the amount of BD which gave a response relative to the interferences present in a standard.
1.2.2. Detection limit of the overall procedure
The detection limit of the overall procedure was 0.60 µg per sample (90 ppb or 200 µg/m 3 ). This amount was determined graphically. It was the amount of analyte which, when spiked on the sampling device, would allow recovery approximately equal to the detection limit of the analytical procedure.
1.2.3. Reliable quantitation limit
The reliable quantitation limit was 1.03 µg per sample (155 ppb or 343 µg/m 3 ). This was the smallest amount of analyte which could be quantitated within the limits of a recovery of at least 75% and a precision (±1.96 SD) of ±25% or better.
1.2.4. Sensitivity 1
1 The reliable quantitation limit and detection limits reported in the method are based upon optimization of the instrument for the smallest possible amount of analyte. When the target concentration of an analyte is exceptionally higher than these limits, they may not be attainable at the routine operation parameters.
The sensitivity of the analytical procedure over a concentration range representing 0.6 to 2 times the target concentration, based on the recommended air volume, was 387 area units per µg/mL. This value was determined from the slope of the calibration curve. The sensitivity may vary with the particular instrument used in the analysis.
1.2.5. Recovery
The recovery of BD from samples used in storage tests remained above 77% when the samples were stored at ambient temperature and above 94% when the samples were stored at refrigerated temperature. These values were determined from regression lines which were calculated from the storage data. The recovery of the analyte from the collection device must be at least 75% following storage.
1.2.6. Precision (analytical method only)
The pooled coefficient of variation obtained from replicate determinations of analytical standards over the range of 0.6 to 2 times the target concentration was 0.011.
1.2.7. Precision (overall procedure)
The precision at the 95% confidence level for the refrigerated temperature storage test was ±12.7%. This value includes an additional ±5% for sampling error. The overall procedure must provide results at the target concentrations that are ±25% at the 95% confidence level.
1.2.8. Reproducibility
Samples collected from a controlled test atmosphere and a draft copy of this procedure were given to a chemist unassociated with this evaluation. The average recovery was 97.2% and the standard deviation was 6.2%.
2. Sampling procedure
2.1. Apparatus
2.1.1. Samples are collected by use of a personal sampling pump that can be calibrated to within ±5% of the recommended 0.05 L/min sampling rate with the sampling tube in line.
2.1.2. Samples are collected with laboratory prepared sampling tubes. The sampling tube is constructed of silane-treated glass and is about 5-cm long. The ID is 4 mm and the OD is 6 mm. One end of the tube is tapered so that a glass wool end plug will hold the contents of the tube in place during sampling. The opening in the tapered end of the sampling tube is at least one-half the ID of the tube (2 mm). The other end of the sampling tube is open to its full 4-mm ID to facilitate packing of the tube. Both ends of the tube are fire-polished for safety. The tube is packed with 2 sections of pretreated charcoal which has been coated with TBC. The tube is packed with a 50-mg backup section, located nearest the tapered end, and with a 100-mg sampling section of charcoal. The two sections of coated adsorbent are separated and retained with small plugs of silanized glass wool. Following packing, the sampling tubes are sealed with two 7/32 inch OD plastic end caps. Instructions for the pretreatment and coating of the charcoal are presented in Section 4.1 of this method.
2.2. Reagents
None required.
2.3. Technique
2.3.1. Properly label the sampling tube before sampling and then remove the plastic end caps.
2.3.2. Attach the sampling tube to the pump using a section of flexible plastic tubing such that the larger front section of the sampling tube is exposed directly to the atmosphere. Do not place any tubing ahead of the sampling tube. The sampling tube should be attached in the worker's breathing zone in a vertical manner such that it does not impede work performance.
2.3.3. After sampling for the appropriate time, remove the sampling tube from the pump and then seal the tube with plastic end caps. Wrap the tube lengthwise.
2.3.4. Include at least one blank for each sampling set. The blank should be handled in the same manner as the samples with the exception that air is not drawn through it.
2.3.5. List any potential interferences on the sample data sheet.
2.3.6. The samples require no special shipping precautions under normal conditions. The samples should be refrigerated if they are to be exposed to higher than normal ambient temperatures. If the samples are to be stored before they are shipped to the laboratory, they should be kept in a freezer. The samples should be placed in a freezer upon receipt at the laboratory.
2.4. Breakthrough
Breakthrough studies have shown that the recommended sampling procedure can be used at air concentrations higher than the target concentration. The sampling time, however, should be reduced to 45 min if both the expected BD level and the relative humidity of the sampled air are high.
2.5. Desorption efficiency
The average desorption efficiency for BD from TBC coated charcoal over the range from 0.6 to 2 times the target concentration was 96.4%. The efficiency was essentially constant over the range studied.
2.6. Recommended air volume and sampling rate
2.6.1. The recommended air volume is 3L.
2.6.2. The recommended sampling rate is 0.05 L/min for 1 hour.
2.7. Interferences
There are no known interferences to the sampling method.
2.8. Safety precautions
2.8.1. Attach the sampling equipment to the worker in such a manner that it will not interfere with work performance or safety.
2.8.2. Follow all safety practices that apply to the work area being sampled.
3. Analytical procedure
3.1. Apparatus
3.1.1. A gas chromatograph (GC), equipped with a flame ionization detector (FID). 2
2 A Hewlett-Packard Model 5840A GC was used for this evaluation. Injections were performed using a Hewlett-Packard Model 7671A automatic sampler.
3.1.2. A GC column capable of resolving the analytes from any interference. 3
3 A 20-ft × 1/8 -inch OD stainless steel GC column containing 20% FFAP on 80/100 mesh Chromabsorb W-AW-DMCS was used for this evaluation.
3.1.3. Vials, glass 2-mL with Teflon-lined caps.
3.1.4. Disposable Pasteur-type pipets, volumetric flasks, pipets and syringes for preparing samples and standards, making dilutions and performing injections.
3.2. Reagents
3.2.1. Carbon disulfide. 4
4 Fisher Scientific Company A.C.S. Reagent Grade solvent was used in this evaluation.
The benzene contaminant that was present in the carbon disulfide was used as an internal standard (ISTD) in this evaluation.
3.2.2. Nitrogen, hydrogen and air, GC grade.
3.2.3. BD of known high purity. 5
5 Matheson Gas Products, CP Grade 1,3-butadiene was used in this study.
3.3. Standard preparation
3.3.1. Prepare standards by diluting known volumes of BD gas with carbon disulfide. This can be accomplished by injecting the appropriate volume of BD into the headspace above the 1-mL of carbon disulfide contained in sealed 2-mL vial. Shake the vial after the needle is removed from the septum. 6
6 A standard containing 7.71 µg/mL (at ambient temperature and pressure) was prepared by diluting 4 µL of the gas with 1-mL of carbon disulfide.
3.3.2. The mass of BD gas used to prepare standards can be determined by use of the following equations:
MV = (760/BP)(273 + t)/(273)(22.41)
Where:
MV = ambient molar volume
BP = ambient barometric pressure
T = ambient temperature
µg/µL = 54.09/MV
µg/standard = (µg/µL)(µL) BD used to prepare the standard
3.4. Sample preparation
3.4.1. Transfer the 100-mg section of the sampling tube to a 2-mL vial. Place the 50-mg section in a separate vial. If the glass wool plugs contain a significant amount of charcoal, place them with the appropriate sampling tube section.
3.4.2. Add 1-mL of carbon disulfide to each vial.
3.4.3. Seal the vials with Teflon-lined caps and then allow them to desorb for one hour. Shake the vials by hand vigorously several times during the desorption period.
3.4.4. If it is not possible to analyze the samples within 4 hours, separate the carbon disulfide from the charcoal, using a disposable Pasteur-type pipet, following the one hour. This separation will improve the stability of desorbed samples.
3.4.5. Save the used sampling tubes to be cleaned and repacked with fresh adsorbent.
3.5. Analysis
3.5.1. GC Conditions
Column temperature: 95 °C
Injector temperature: 180 °C
Detector temperature: 275 °C
Carrier gas flow rate: 30 mL/min
Injection volume: 0.80 µL
GC column: 20-ft × 1/8 -in OD stainless steel GC column containing 20%
FFAP on 80/100 Chromabsorb W-AW-DMCS.
3.5.2. Chromatogram. See Section 4.2.
3.5.3. Use a suitable method, such as electronic or peak heights, to measure detector response.
3.5.4. Prepare a calibration curve using several standard solutions of different concentrations. Prepare the calibration curve daily. Program the integrator to report the results in µg/mL.
3.5.5. Bracket sample concentrations with standards.
3.6. Interferences (analytical)
3.6.1. Any compound with the same general retention time as the analyte and which also gives a detector response is a potential interference. Possible interferences should be reported by the industrial hygienist to the laboratory with submitted samples.
3.6.2. GC parameters (temperature, column, etc.) may be changed to circumvent interferences.
3.6.3. A useful means of structure designation is GC/MS. It is recommended that this procedure be used to confirm samples whenever possible.
3.7. Calculations
3.7.1. Results are obtained by use of calibration curves. Calibration curves are prepared by plotting detector response against concentration for each standard. The best line through the data points is determined by curve fitting.
3.7.2. The concentration, in ug/mL, for a particular sample is determined by comparing its detector response to the calibration curve. If any analyte is found on the backup section, this amount is added to the amount found on the front section. Blank corrections should be performed before adding the results together.
3.7.3. The BD air concentration can be expressed using the following equation:
3
Where:
A = µg/mL from Section 3.7.2
B = volume
C = L of air sampled
D = efficiency
3.7.4. The following equation can be used to convert results in mg/m 3 to ppm:
3
Where:
3
24.46 = molar volume of an ideal gas at 760 mm Hg and 25 °C.
3.8. Safety precautions (analytical)
3.8.1. Avoid skin contact and inhalation of all chemicals.
3.8.2. Restrict the use of all chemicals to a fume hood whenever possible.
3.8.3. Wear safety glasses and a lab coat in all laboratory areas.
4. Additional Information
4.1. A procedure to prepare specially cleaned charcoal coated with TBC
4.1.1. Apparatus
4.1.1.1. Magnetic stirrer and stir bar.
4.1.1.2. Tube furnace capable of maintaining a temperature of 700 °C and equipped with a quartz tube that can hold 30 g of charcoal. 8
8 A Lindberg Type 55035 Tube furnace was used in this evaluation.
4.1.1.3. A means to purge nitrogen gas through the charcoal inside the quartz tube.
4.1.1.4. Water bath capable of maintaining a temperature of 60 °C.
4.1.1.5. Miscellaneous laboratory equipment: One-liter vacuum flask, 1-L Erlenmeyer flask, 350-M1 Buchner funnel with a coarse fitted disc, 4-oz brown bottle, rubber stopper, Teflon tape etc.
4.1.2. Reagents
4.1.2.1. Phosphoric acid, 10% by weight, in water. 9
9 Baker Analyzed” Reagent grade was diluted with water for use in this evaluation.
4.1.2.2. 4-tert-Butylcatechol (TBC). 10
10 The Aldrich Chemical Company 99% grade was used in this evaluation.
4.1.2.3. Specially cleaned coconut shell charcoal, 20/40 mesh. 11
11 Specially cleaned charcoal was obtained from Supelco, Inc. for use in this evaluation. The cleaning process used by Supelco is proprietary.
4.1.2.4. Nitrogen gas, GC grade.
4.1.3. Procedure
Weigh 30g of charcoal into a 500-mL Erlenmeyer flask. Add about 250 mL of 10% phosphoric acid to the flask and then swirl the mixture. Stir the mixture for 1 hour using a magnetic stirrer. Filter the mixture using a fitted Buchner funnel. Wash the charcoal several times with 250-mL portions of deionized water to remove all traces of the acid. Transfer the washed charcoal to the tube furnace quartz tube. Place the quartz tube in the furnace and then connect the nitrogen gas purge to the tube. Fire the charcoal to 700 °C. Maintain that temperature for at least 1 hour. After the charcoal has cooled to room temperature, transfer it to a tared beaker. Determine the weight of the charcoal and then add an amount of TBC which is 10% of the charcoal, by weight.
CAUTION-TBC is toxic and should only be handled in a fume hood while wearing gloves.
Carefully mix the contents of the beaker and then transfer the mixture to a 4-oz bottle. Stopper the bottle with a clean rubber stopper which has been wrapped with Teflon tape. Clamp the bottle in a water bath so that the water level is above the charcoal level. Gently heat the bath to 60 °C and then maintain that temperature for 1 hour. Cool the charcoal to room temperature and then transfer the coated charcoal to a suitable container.
The coated charcoal is now ready to be packed into sampling tubes. The sampling tubes should be stored in a sealed container to prevent contamination. Sampling tubes should be stored in the dark at room temperature. The sampling tubes should be segregated by coated adsorbent lot number.
4.2 Chromatograms
The chromatograms were obtained using the recommended analytical method. The chart speed was set at 1 cm/min for the first three min and then at 0.2 cm/min for the time remaining in the analysis.
The peak which elutes just before BD is a reaction product between an impurity on the charcoal and TBC. This peak is always present, but it is easily resolved from the analyte. The peak which elutes immediately before benzene is an oxidation product of TBC.
5. References
5.1. “Current Intelligence Bulletin 41, 1,3-Butadiene”, U.S. Dept. of Health and Human Services, Public Health Service, Center for Disease Control, NIOSH.
5.2. “NIOSH Manual of Analytical Methods”, 2nd ed; U.S. Dept. of Health Education and Welfare, National Institute for Occupational Safety and Health: Cincinnati, OH. 1977, Vol. 2, Method No. S91 DHEW (NIOSH) Publ. (US), No. 77-157-B.
5.3. Hawley, G.C., Ed. “The Condensed Chemical Dictionary”, 8th ed.; Van Nostrand Rienhold Company: New York, 1971; 139.5.4. Chem. Eng. News (June 10, 1985), (63), 22-66.
Appendix F to § 1910.1051—Medical Questionnaires (Non-Mandatory)
[61 FR 56831, Nov. 4, 1996, as amended at 63 FR 1294, Jan. 8, 1998; 67 FR 67965, Nov. 7, 2002; 70 FR 1143, Jan. 5, 2005; 71 FR 16672, 16674, Apr. 3, 2006; 73 FR 75587, Dec. 12, 2008; 76 FR 33609, June 8, 2011; 77 FR 17785, Mar. 26, 2012; 78 FR 9313, Feb. 8, 2013; 84 FR 21527, May 14, 2019]
This occupational health standard establishes requirements for employers to control occupational exposure to methylene chloride (MC). Employees exposed to MC are at increased risk of developing cancer, adverse effects on the heart, central nervous system and liver, and skin or eye irritation. Exposure may occur through inhalation, by absorption through the skin, or through contact with the skin. MC is a solvent which is used in many different types of work activities, such as paint stripping, polyurethane foam manufacturing, and cleaning and degreasing. Under the requirements of paragraph (d) of this section, each covered employer must make an initial determination of each employee's exposure to MC. If the employer determines that employees are exposed below the action level, the only other provisions of this section that apply are that a record must be made of the determination, the employees must receive information and training under paragraph (l) of this section and, where appropriate, employees must be protected from contact with liquid MC under paragraph (h) of this section. The provisions of the MC standard are as follows:
This section applies to all occupational exposures to methylene chloride (MC), Chemical Abstracts Service Registry Number 75-09-2, in general industry, construction and shipyard employment.
For the purposes of this section, the following definitions shall apply:
Action level means a concentration of airborne MC of 12.5 parts per million (ppm) calculated as an eight (8)-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer and required by work duties to be present in regulated areas, or any person entering such an area as a designated representative of employees for the purpose of exercising the right to observe monitoring and measuring procedures under paragraph (d) of this section, or any other person authorized by the OSH Act or regulations issued under the Act.
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence, such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment, which results, or is likely to result in an uncontrolled release of MC. If an incidental release of MC can be controlled by employees such as maintenance personnel at the time of release and in accordance with the leak/spill provisions required by paragraph (f) of this section, it is not considered an emergency as defined by this standard.
Employee exposure means exposure to airborne MC which occurs or would occur if the employee were not using respiratory protection.
Methylene chloride (MC) means an organic compound with chemical formula, CH 2 Cl 2. Its Chemical Abstracts Service Registry Number is 75-09-2. Its molecular weight is 84.9 g/mole.
Physician or other licensed health care professional is an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the health care services required by paragraph (j) of this section.
Regulated area means an area, demarcated by the employer, where an employee's exposure to airborne concentrations of MC exceeds or can reasonably be expected to exceed either the 8-hour TWA PEL or the STEL.
Symptom means central nervous system effects such as headaches, disorientation, dizziness, fatigue, and decreased attention span; skin effects such as chapping, erythema, cracked skin, or skin burns; and cardiac effects such as chest pain or shortness of breath.
This section means this methylene chloride standard.
The employer shall ensure that no employee is exposed to an airborne concentration of MC in excess of twenty-five parts of MC per million parts of air (25 ppm) as an 8-hour TWA.
The employer shall ensure that no employee is exposed to an airborne concentration of MC in excess of one hundred and twenty-five parts of MC per million parts of air (125 ppm) as determined over a sampling period of fifteen minutes.
The employer may consider personal breathing zone air samples to be representative of employee exposures when they are taken as follows:
The employer has taken one or more personal breathing zone air samples for at least one employee in each job classification in a work area during every work shift, and the employee sampled is expected to have the highest MC exposure.
The employer has taken one or more personal breathing zone air samples which indicate the highest likely 15-minute exposures during such operations for at least one employee in each job classification in the work area during every work shift, and the employee sampled is expected to have the highest MC exposure.
Personal breathing zone air samples taken during one work shift may be used to represent employee exposures on other work shifts where the employer can document that the tasks performed and conditions in the workplace are similar across shifts.
The employer shall ensure that the methods used to perform exposure monitoring produce results that are accurate to a confidence level of 95 percent, and are:
Each employer whose employees are exposed to MC shall perform initial exposure monitoring to determine each affected employee's exposure, except under the following conditions:
Where the initial determination shows employee exposures at or above the action level or above the STEL, the employer shall establish an exposure monitoring program for periodic monitoring of employee exposure to MC in accordance with Table 1:
| Exposure scenario | Required monitoring activity |
|---|---|
| Below the action level and at or below the STEL | No 8-hour TWA or STEL monitoring required. |
| Below the action level and above the STEL | No 8-hour TWA monitoring required; monitor STEL exposures every three months. |
| At or above the action level, at or below the TWA, and at or below the STEL | Monitor 8-hour TWA exposures every six months. |
| At or above the action level, at or below the TWA, and above the STEL | Monitor 8-hour TWA exposures every six months and monitor STEL exposures every three months. |
| Above the TWA and at or below the STEL | Monitor 8-hour TWA exposures every three months. In addition, without regard to the last sentence of the note to paragraph (d)(3), the following employers must monitor STEL exposures every three months until either the date by which they must achieve the 8-hour TWA PEL under paragraph (n) of this section or the date by which they in fact achieve the 8-hour TWA PEL, whichever comes first: employers engaged in polyurethane foam manufacturing; foam fabrication; furniture refinishing; general aviation aircraft stripping; product formulation; use of MC-based adhesives for boat building and repair, recreational vehicle manufacture, van conversion, or upholstery; and use of MC in construction work for restoration and preservation of buildings, painting and paint removal, cabinet making, or floor refinishing and resurfacing. |
| Above the TWA and above the STEL | Monitor 8-hour TWA exposures and STEL exposures every three months. |
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to MC conducted in accordance with this section.
When observation of the monitoring of employee exposure to MC requires entry into an area where the use of protective clothing or equipment is required, the employer shall provide, at no cost to the observer(s), and the observer(s) shall be required to use such clothing and equipment and shall comply with all other applicable safety and health procedures.
The employer shall institute and maintain the effectiveness of engineering controls and work practices to reduce employee exposure to or below the PELs except to the extent that the employer can demonstrate that such controls are not feasible. Wherever the feasible engineering controls and work practices which can be instituted are not sufficient to reduce employee exposure to or below the 8-TWA PEL or STEL, the employer shall use them to reduce employee exposure to the lowest levels achievable by these controls and shall supplement them by the use of respiratory protection that complies with the requirements of paragraph (g) of this section.
The employer shall not implement a schedule of employee rotation as a means of compliance with the PELs.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Employers must:
Before having an employee use a supplied-air respirator in the negative-pressure mode, or a gas mask with an organic-vapor canister for emergency escape, the employer must:
The employer shall make medical surveillance available for employees who are or may be exposed to MC as follows:
The employer shall provide all required medical surveillance at no cost to affected employees, without loss of pay and at a reasonable time and place.
The employer shall ensure that all medical surveillance procedures are performed by a physician or other licensed health care professional, as defined in paragraph (b) of this section.
The employer shall make medical surveillance available to each affected employee as follows:
The employer shall provide initial medical surveillance under the schedule provided by paragraph (n)(2)(iii) of this section, or before the time of initial assignment of the employee, whichever is later. The employer need not provide the initial surveillance if medical records show that an affected employee has been provided with medical surveillance that complies with this section within 12 months before April 10, 1997.
The employer shall update the medical and work history for each affected employee annually. The employer shall provide periodic physical examinations, including appropriate laboratory surveillance, as follows:
When an employee leaves the employer's workplace, or is reassigned to an area where exposure to MC is consistently at or below the action level and STEL, medical surveillance shall be made available if six months or more have elapsed since the last medical surveillance.
The employer shall provide additional medical surveillance at frequencies other than those listed above when recommended in the written medical opinion. (For example, the physician or other licensed health care professional may determine an examination is warranted in less than 36 months for employees younger than 45 years of age based upon evaluation of the results of the annual medical and work history.)
The comprehensive medical and work history shall emphasize neurological symptoms, skin conditions, history of hematologic or liver disease, signs or symptoms suggestive of heart disease (angina, coronary artery disease), risk factors for cardiac disease, MC exposures, and work practices and personal protective equipment used during such exposures.
Where physical examinations are provided as required above, the physician or other licensed health care professional shall accord particular attention to the lungs, cardiovascular system (including blood pressure and pulse), liver, nervous system, and skin. The physician or other licensed health care professional shall determine the extent and nature of the physical examination based on the health status of the employee and analysis of the medical and work history.
The physician or other licensed health care professional shall determine the extent of any required laboratory surveillance based on the employee's observed health status and the medical and work history.
The medical surveillance shall also include any other information or reports the physician or other licensed health care professional determines are necessary to assess the employee's health in relation to MC exposure.
The employer shall ensure that medical surveillance made available when an employee has been exposed to MC in emergency situations includes, at a minimum:
Where the physician or other licensed health care professional determines it is necessary, the scope of the medical examination shall be expanded and the appropriate additional medical surveillance, such as referrals for consultation or examination, shall be provided.
For purposes of this paragraph (j) of this section, the physician or other licensed health care professional shall presume, unless medical evidence indicates to the contrary, that a medical condition is unlikely to require medical removal from MC exposure if the employee is not exposed to MC above the 8-hour TWA PEL. If the physician or other licensed health care professional recommends removal for an employee exposed below the 8-hour TWA PEL, the physician or other licensed health care professional shall cite specific medical evidence, sufficient to rebut the presumption that exposure below the 8-hour TWA PEL is unlikely to require removal, to support the recommendation. If such evidence is cited by the physician or other licensed health care professional, the employer must remove the employee. If such evidence is not cited by the physician or other licensed health care professional, the employer is not required to remove the employee.
Where an employer, although not required by this section to do so, removes an employee from exposure to MC or otherwise places any limitation on an employee due to the effects of MC exposure on the employee's medical condition, the employer shall provide medical removal protection benefits to the employee equal to those required by paragraph (j)(12) of this section.
The employer shall comply with the requirements concerning transfer of records set forth in 29 CFR 1910.1020(h).
The information contained in the appendices does not, by itself, create any additional obligations not otherwise imposed or detract from any existing obligation.
Appendix A to Section 1910.1052—Substance Safety Data Sheet and Technical Guidelines for Methylene Chloride
I. Substance Identification
A. Substance: Methylene chloride (CH 2 Cl 2 ).
B. Synonyms: MC, Dichloromethane (DCM); Methylene dichloride; Methylene bichloride; Methane dichloride; CAS: 75-09-2; NCI-C50102.
C. Physical data:
1. Molecular weight: 84.9.
2. Boiling point (760 mm Hg): 39.8 °C (104 °F).
3. Specific gravity (water = 1): 1.3.
4. Vapor density (air = 1 at boiling point): 2.9.
5. Vapor pressure at 20 °C (68 °F): 350 mm Hg.
6. Solubility in water, g/100 g water at 20 °C (68 °F) = 1.32.
7. Appearance and odor: colorless liquid with a chloroform-like odor.
D. Uses:
MC is used as a solvent, especially where high volatility is required. It is a good solvent for oils, fats, waxes, resins, bitumen, rubber and cellulose acetate and is a useful paint stripper and degreaser. It is used in paint removers, in propellant mixtures for aerosol containers, as a solvent for plastics, as a degreasing agent, as an extracting agent in the pharmaceutical industry and as a blowing agent in polyurethane foams. Its solvent property is sometimes increased by mixing with methanol, petroleum naphtha or tetrachloroethylene.
E. Appearance and odor:
MC is a clear colorless liquid with a chloroform-like odor. It is slightly soluble in water and completely miscible with most organic solvents.
F. Permissible exposure:
Exposure may not exceed 25 parts MC per million parts of air (25 ppm) as an eight-hour time-weighted average (8-hour TWA PEL) or 125 parts of MC per million parts of air (125 ppm) averaged over a 15-minute period (STEL).
II. Health Hazard Data
A. MC can affect the body if it is inhaled or if the liquid comes in contact with the eyes or skin. It can also affect the body if it is swallowed.
B. Effects of overexposure:
1. Short-term Exposure:
MC is an anesthetic. Inhaling the vapor may cause mental confusion, light-headedness, nausea, vomiting, and headache. Continued exposure may cause increased light-headedness, staggering, unconsciousness, and even death. High vapor concentrations may also cause irritation of the eyes and respiratory tract. Exposure to MC may make the symptoms of angina (chest pains) worse. Skin exposure to liquid MC may cause irritation. If liquid MC remains on the skin, it may cause skin burns. Splashes of the liquid into the eyes may cause irritation.
2. Long-term (chronic) exposure:
The best evidence that MC causes cancer is from laboratory studies in which rats, mice and hamsters inhaled MC 6 hours per day, 5 days per week for 2 years. MC exposure produced lung and liver tumors in mice and mammary tumors in rats. No carcinogenic effects of MC were found in hamsters.
There are also some human epidemiological studies which show an association between occupational exposure to MC and increases in biliary (bile duct) cancer and a type of brain cancer. Other epidemiological studies have not observed a relationship between MC exposure and cancer. OSHA interprets these results to mean that there is suggestive (but not absolute) evidence that MC is a human carcinogen.
C. Reporting signs and symptoms:
You should inform your employer if you develop any signs or symptoms and suspect that they are caused by exposure to MC.
D. Warning Properties:
1. Odor Threshold:
Different authors have reported varying odor thresholds for MC. Kirk-Othmer and Sax both reported 25 to 50 ppm; Summer and May both reported 150 ppm; Spector reports 320 ppm. Patty, however, states that since one can become adapted to the odor, MC should not be considered to have adequate warning properties.
2. Eye Irritation Level:
Kirk-Othmer reports that “MC vapor is seriously damaging to the eyes.” Sax agrees with Kirk-Othmer's statement. The ACGIH Documentation of TLVs states that irritation of the eyes has been observed in workers exposed to concentrations up to 5000 ppm.
3. Evaluation of Warning Properties:
Since a wide range of MC odor thresholds are reported (25-320 ppm), and human adaptation to the odor occurs, MC is considered to be a material with poor warning properties.
III. Emergency First Aid Procedures
In the event of emergency, institute first aid procedures and send for first aid or medical assistance.
A. Eye and Skin Exposures:
If there is a potential for liquid MC to come in contact with eye or skin, face shields and skin protective equipment must be provided and used. If liquid MC comes in contact with the eye, get medical attention. Contact lenses should not be worn when working with this chemical.
B. Breathing:
If a person breathes in large amounts of MC, move the exposed person to fresh air at once. If breathing has stopped, perform cardiopulmorary resuscitation. Keep the affected person warm and at rest. Get medical attention as soon as possible.
C. Rescue:
Move the affected person from the hazardous exposure immediately. If the exposed person has been overcome, notify someone else and put into effect the established emergency rescue procedures. Understand the facility's emergency rescue procedures and know the locations of rescue equipment before the need arises. Do not become a casualty yourself.
IV. Respirators, Protective Clothing, and Eye Protection
A. Respirators:
Good industrial hygiene practices recommend that engineering controls be used to reduce environmental concentrations to the permissible exposure level. However, there are some exceptions where respirators may be used to control exposure. Respirators may be used when engineering and work practice controls are not feasible, when such controls are in the process of being installed, or when these controls fail and need to be supplemented. Respirators may also be used for operations which require entry into tanks or closed vessels, and in emergency situations.
If the use of respirators is necessary, the only respirators permitted are those that have been approved by the Mine Safety and Health Administration (MSHA) or the National Institute for Occupational Safety and Health (NIOSH). Supplied-air respirators are required because air-purifying respirators do not provide adequate respiratory protection against MC.
In addition to respirator selection, a complete written respiratory protection program should be instituted which includes regular training, maintenance, inspection, cleaning, and evaluation. If you can smell MC while wearing a respirator, proceed immediately to fresh air. If you experience difficulty in breathing while wearing a respirator, tell your employer.
B. Protective Clothing:
Employees must be provided with and required to use impervious clothing, gloves, face shields (eight-inch minimum), and other appropriate protective clothing necessary to prevent repeated or prolonged skin contact with liquid MC or contact with vessels containing liquid MC. Any clothing which becomes wet with liquid MC should be removed immediately and not reworn until the employer has ensured that the protective clothing is fit for reuse. Contaminated protective clothing should be placed in a regulated area designated by the employer for removal of MC before the clothing is laundered or disposed of. Clothing and equipment should remain in the regulated area until all of the MC contamination has evaporated; clothing and equipment should then be laundered or disposed of as appropriate.
C. Eye Protection:
Employees should be provided with and required to use splash-proof safety goggles where liquid MC may contact the eyes.
V. Housekeeping and Hygiene Facilities
For purposes of complying with 29 CFR 1910.141, the following items should be emphasized:
A. The workplace should be kept clean, orderly, and in a sanitary condition. The employer should institute a leak and spill detection program for operations involving liquid MC in order to detect sources of fugitive MC emissions.
B. Emergency drench showers and eyewash facilities are recommended. These should be maintained in a sanitary condition. Suitable cleansing agents should also be provided to assure the effective removal of MC from the skin.
C. Because of the hazardous nature of MC, contaminated protective clothing should be placed in a regulated area designated by the employer for removal of MC before the clothing is laundered or disposed of.
VI. Precautions for Safe Use, Handling, and Storage
A. Fire and Explosion Hazards:
MC has no flash point in a conventional closed tester, but it forms flammable vapor-air mixtures at approximately 100 °C (212 °F), or higher. It has a lower explosion limit of 12%, and an upper explosion limit of 19% in air. It has an autoignition temperature of 556.1 °C (1033 °F), and a boiling point of 39.8 °C (104 °F). It is heavier than water with a specific gravity of 1.3. It is slightly soluble in water.
B. Reactivity Hazards:
Conditions contributing to the instability of MC are heat and moisture. Contact with strong oxidizers, caustics, and chemically active metals such as aluminum or magnesium powder, sodium and potassium may cause fires and explosions.
Special precautions: Liquid MC will attack some forms of plastics, rubber, and coatings.
C. Toxicity:
Liquid MC is painful and irritating if splashed in the eyes or if confined on the skin by gloves, clothing, or shoes. Vapors in high concentrations may cause narcosis and death. Prolonged exposure to vapors may cause cancer or exacerbate cardiac disease.
D. Storage:
Protect against physical damage. Because of its corrosive properties, and its high vapor pressure, MC should be stored in plain, galvanized or lead lined, mild steel containers in a cool, dry, well ventilated area away from direct sunlight, heat source and acute fire hazards.
E. Piping Material:
All piping and valves at the loading or unloading station should be of material that is resistant to MC and should be carefully inspected prior to connection to the transport vehicle and periodically during the operation.
F. Usual Shipping Containers:
Glass bottles, 5- and 55-gallon steel drums, tank cars, and tank trucks.
G. Electrical Equipment:
Electrical installations in Class I hazardous locations as defined in Article 500 of the National Electrical Code, should be installed according to Article 501 of the code; and electrical equipment should be suitable for use in atmospheres containing MC vapors. See Flammable and Combustible Liquids Code (NFPA No. 325M), Chemical Safety Data Sheet SD-86 (Manufacturing Chemists' Association, Inc.).
H. Fire Fighting:
When involved in fire, MC emits highly toxic and irritating fumes such as phosgene, hydrogen chloride and carbon monoxide. Wear breathing apparatus and use water spray to keep fire-exposed containers cool. Water spray may be used to flush spills away from exposures. Extinguishing media are dry chemical, carbon dioxide, foam. For purposes of compliance with 29 CFR 1910.307, locations classified as hazardous due to the presence of MC shall be Class I.
I. Spills and Leaks:
Persons not wearing protective equipment and clothing should be restricted from areas of spills or leaks until cleanup has been completed. If MC has spilled or leaked, the following steps should be taken:
1. Remove all ignition sources.
2. Ventilate area of spill or leak.
3. Collect for reclamation or absorb in vermiculite, dry sand, earth, or a similar material.
J. Methods of Waste Disposal:
Small spills should be absorbed onto sand and taken to a safe area for atmospheric evaporation. Incineration is the preferred method for disposal of large quantities by mixing with a combustible solvent and spraying into an incinerator equipped with acid scrubbers to remove hydrogen chloride gases formed. Complete combustion will convert carbon monoxide to carbon dioxide. Care should be taken for the presence of phosgene.
K. You should not keep food, beverage, or smoking materials, or eat or smoke in regulated areas where MC concentrations are above the permissible exposure limits.
L. Portable heating units should not be used in confined areas where MC is used.
M. Ask your supervisor where MC is used in your work area and for any additional plant safety and health rules.
VII. Medical Requirements
Your employer is required to offer you the opportunity to participate in a medical surveillance program if you are exposed to MC at concentrations at or above the action level (12.5 ppm 8-hour TWA) for more than 30 days a year or at concentrations exceeding the PELs (25 ppm 8-hour TWA or 125 ppm 15-minute STEL) for more than 10 days a year. If you are exposed to MC at concentrations over either of the PELs, your employer will also be required to have a physician or other licensed health care professional ensure that you are able to wear the respirator that you are assigned. Your employer must provide all medical examinations relating to your MC exposure at a reasonable time and place and at no cost to you.
VIII. Monitoring and Measurement Procedures
A. Exposure above the Permissible Exposure Limit:
1. Eight-hour exposure evaluation: Measurements taken for the purpose of determining employee exposure under this section are best taken with consecutive samples covering the full shift. Air samples must be taken in the employee's breathing zone.
2. Monitoring techniques: The sampling and analysis under this section may be performed by collection of the MC vapor on two charcoal adsorption tubes in series or other composition adsorption tubes, with subsequent chemical analysis. Sampling and analysis may also be performed by instruments such as real-time continuous monitoring systems, portable direct reading instruments, or passive dosimeters as long as measurements taken using these methods accurately evaluate the concentration of MC in employees” breathing zones.
OSHA method 80 is an example of a validated method of sampling and analysis of MC. Copies of this method are available from OSHA or can be downloaded from the Internet at http://www.osha.gov. The employer has the obligation of selecting a monitoring method which meets the accuracy and precision requirements of the standard under his or her unique field conditions. The standard requires that the method of monitoring must be accurate, to a 95 percent confidence level, to plus or minus 25 percent for concentrations of MC at or above 25 ppm, and to plus or minus 35 percent for concentrations at or below 25 ppm. In addition to OSHA method 80, there are numerous other methods available for monitoring for MC in the workplace.
B. Since many of the duties relating to employee exposure are dependent on the results of measurement procedures, employers must assure that the evaluation of employee exposure is performed by a technically qualified person.
IX. Observation of Monitoring
Your employer is required to perform measurements that are representative of your exposure to MC and you or your designated representative are entitled to observe the monitoring procedure. You are entitled to observe the steps taken in the measurement procedure, and to record the results obtained. When the monitoring procedure is taking place in an area where respirators or personal protective clothing and equipment are required to be worn, you or your representative must also be provided with, and must wear, protective clothing and equipment.
X. Access to Information
A. Your employer is required to inform you of the information contained in this Appendix. In addition, your employer must instruct you in the proper work practices for using MC, emergency procedures, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being exposed to MC. You or your representative has the right to observe employee measurements and to record the results obtained. Your employer is required to inform you of your exposure. If your employer determines that you are being over exposed, he or she is required to inform you of the actions which are being taken to reduce your exposure to within permissible exposure limits.
C. Your employer is required to keep records of your exposures and medical examinations. These records must be kept by the employer for at least thirty (30) years.
D. Your employer is required to release your exposure and medical records to you or your representative upon your request.
E. Your employer is required to provide labels and safety data sheets (SDSs) for all materials, mixtures or solutions composed of greater than 0.1 percent MC. These materials, mixtures or solutions would be classified and labeled in accordance with § 1910.1200.
Danger Contains Methylene Chloride Potential Cancer Hazard
May worsen heart disease because methylene chloride is converted to carbon monoxide in the body.
May cause dizziness, headache, irritation of the throat and lungs, loss of consciousness and death at high concentrations (for example, if used in a poorly ventilated room).
Avoid Skin Contact. Contact with liquid causes skin and eye irritation.
XI. Common Operations and Controls
The following list includes some common operations in which exposure to MC may occur and control methods which may be effective in each case:
| Operations | Controls |
|---|---|
| Use as solvent in paint and varnish removers; manufacture of aerosols; cold cleaning and ultrasonic cleaning; and as a solvent in furniture stripping | General dilution ventilation; local exhaust ventilation; personal protective equipment; substitution. |
| Use as solvent in vapor degreasing | Process enclosure; local exhaust ventilation; chilling coils; substitution. |
| Use as a secondary refrigerant in air conditioning and scientific testing | General dilution ventilation; local exhaust ventilation; personal protective equipment. |
Appendix B to Section 1910.1052—Medical Surveillance for Methylene Chloride
I. Primary Route of Entry
Inhalation.
II. Toxicology
Methylene Chloride (MC) is primarily an inhalation hazard. The principal acute hazardous effects are the depressant action on the central nervous system, possible cardiac toxicity and possible liver toxicity. The range of CNS effects are from decreased eye/hand coordination and decreased performance in vigilance tasks to narcosis and even death of individuals exposed at very high doses. Cardiac toxicity is due to the metabolism of MC to carbon monoxide, and the effects of carbon monoxide on heart tissue. Carbon monoxide displaces oxygen in the blood, decreases the oxygen available to heart tissue, increasing the risk of damage to the heart, which may result in heart attacks in susceptible individuals. Susceptible individuals include persons with heart disease and those with risk factors for heart disease.
Elevated liver enzymes and irritation to the respiratory passages and eyes have also been reported for both humans and experimental animals exposed to MC vapors.
MC is metabolized to carbon monoxide and carbon dioxide via two separate pathways. Through the first pathway, MC is metabolized to carbon monoxide as an end-product via the P-450 mixed function oxidase pathway located in the microsomal fraction of the cell. This biotransformation of MC to carbon monoxide occurs through the process of microsomal oxidative dechlorination which takes place primarily in the liver. The amount of conversion to carbon monoxide is significant as measured by the concentration of carboxyhemoglobin, up to 12% measured in the blood following occupational exposure of up to 610 ppm. Through the second pathway, MC is metabolized to carbon dioxide as an end product (with formaldehyde and formic acid as metabolic intermediates) via the glutathione dependent enzyme found in the cytosolic fraction of the liver cell. Metabolites along this pathway are believed to be associated with the carcinogenic activity of MC.
MC has been tested for carcinogenicity in several laboratory rodents. These rodent studies indicate that there is clear evidence that MC is carcinogenic to male and female mice and female rats. Based on epidemiologic studies, OSHA has concluded that there is suggestive evidence of increased cancer risk in MC-related worker populations. The epidemiological evidence is consistent with the finding of excess cancer in the experimental animal studies. NIOSH regards MC as a potential occupational carcinogen and the International Agency for Research Cancer (IARC) classifies MC as an animal carcinogen. OSHA considers MC as a suspected human carcinogen.
III. Medical Signs and Symptoms of Acute Exposure
Skin exposure to liquid MC may cause irritation or skin burns. Liquid MC can also be irritating to the eyes. MC is also absorbed through the skin and may contribute to the MC exposure by inhalation.
At high concentrations in air, MC may cause nausea, vomiting, light-headedness, numbness of the extremities, changes in blood enzyme levels, and breathing problems, leading to bronchitis and pulmonary edema, unconsciousness and even death.
At lower concentrations in air, MC may cause irritation to the skin, eye, and respiratory tract and occasionally headache and nausea. Perhaps the greatest problem from exposure to low concentrations of MC is the CNS effects on coordination and alertness that may cause unsafe operations of machinery and equipment, leading to self-injury or accidents.
Low levels and short duration exposures do not seem to produce permanent disability, but chronic exposures to MC have been demonstrated to produce liver toxicity in animals, and therefore, the evidence is suggestive for liver toxicity in humans after chronic exposure.
Chronic exposure to MC may also cause cancer.
IV. Surveillance and Preventive Considerations
As discussed in sections II and III of this appendix, MC is classified as a suspect or potential human carcinogen. It is a central nervous system (CNS) depressant and a skin, eye and respiratory tract irritant. At extremely high concentrations, MC has caused liver damage in animals. MC principally affects the CNS, where it acts as a narcotic. The observation of the symptoms characteristic of CNS depression, along with a physical examination, provides the best detection of early neurological disorders. Since exposure to MC also increases the carboxyhemoglobin level in the blood, ambient carbon monoxide levels would have an additive effect on that carboxyhemoglobin level. Based on such information, a periodic post-shift carboxyhemoglobin test as an index of the presence of carbon monoxide in the blood is recommended, but not required, for medical surveillance.
Based on the animal evidence and three epidemiologic studies previously mentioned, OSHA concludes that MC is a suspect human carcinogen. The medical surveillance program is designed to observe exposed workers on a regular basis. While the medical surveillance program cannot detect MC-induced cancer at a preneoplastic stage, OSHA anticipates that, as in the past, early detection and treatments of cancers leading to enhanced survival rates will continue to evolve.
A. Medical and Occupational History
The medical and occupational work history plays an important role in the initial evaluation of workers exposed to MC. It is therefore extremely important for the examining physician or other licensed health care professional to evaluate the MC-exposed worker carefully and completely and to focus the examination on MC's potentially associated health hazards. The medical evaluation must include an annual detailed work and medical history with special emphasis on cardiac history and neurological symptoms.
An important goal of the medical history is to elicit information from the worker regarding potential signs or symptoms associated with increased levels of carboxyhemoglobin due to the presence of carbon monoxide in the blood. Physicians or other licensed health care professionals should ensure that the smoking history of all MC exposed employees is known. Exposure to MC may cause a significant increase in carboxyhemoglobin level in all exposed persons. However, smokers as well as workers with anemia or heart disease and those concurrently exposed to carbon monoxide are at especially high risk of toxic effects because of an already reduced oxygen carrying capacity of the blood.
A comprehensive or interim medical and work history should also include occurrence of headache, dizziness, fatigue, chest pain, shortness of breath, pain in the limbs, and irritation of the skin and eyes.
In addition, it is important for the physician or other licensed health care professional to become familiar with the operating conditions in which exposure to MC is likely to occur. The physician or other licensed health care professional also must become familiar with the signs and symptoms that may indicate that a worker is receiving otherwise unrecognized and exceptionally high exposure levels of MC.
An example of a medical and work history that would satisfy the requirement for a comprehensive or interim work history is represented by the following:
The following is a list of recommended questions and issues for the self-administered questionnaire for methylene chloride exposure.
Appendix C to Section 1910.1052—Questions and Answers—Methylene Chloride Control in Furniture Stripping
[62 FR 1601, Jan. 10, 1997, as amended at 62 FR 42667, Aug. 8, 1997; 62 FR 54383, Oct. 20, 1997; 62 FR 66277, Dec. 18, 1997; 63 FR 1295, Jan. 8, 1998; 63 FR 20099, Apr. 23, 1998; 63 FR 50729, Sept. 22, 1998; 71 FR 16674, Apr. 3, 2006; 71 FR 50190, Aug. 24, 2006; 73 FR 75587, Dec. 12, 2008; 77 FR 17785, Mar. 26, 2012; 78 FR 9313, Feb. 8, 2013; 84 FR 21555, May 14, 2019]
For the purposes of this section the following definitions apply:
Action level means a concentration of airborne respirable crystalline silica of 25 µg/m 3, calculated as an 8-hour TWA.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Employee exposure means the exposure to airborne respirable crystalline silica that would occur if the employee were not using a respirator.
High-efficiency particulate air [HEPA] filter means a filter that is at least 99.97 percent efficient in removing mono-dispersed particles of 0.3 micrometers in diameter.
Objective data means information, such as air monitoring data from industry-wide surveys or calculations based on the composition of a substance, demonstrating employee exposure to respirable crystalline silica associated with a particular product or material or a specific process, task, or activity. The data must reflect workplace conditions closely resembling or with a higher exposure potential than the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Physician or other licensed health care professional [PLHCP] means an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required by paragraph (i) of this section.
Regulated area means an area, demarcated by the employer, where an employee's exposure to airborne concentrations of respirable crystalline silica exceeds, or can reasonably be expected to exceed, the PEL.
Respirable crystalline silica means quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirable-particle-size-selective samplers specified in the International Organization for Standardization (ISO) 7708:1995: Air Quality—Particle Size Fraction Definitions for Health-Related Sampling.
Specialist means an American Board Certified Specialist in Pulmonary Disease or an American Board Certified Specialist in Occupational Medicine.
This section means this respirable crystalline silica standard, 29 CFR 1910.1053.
The employer shall ensure that no employee is exposed to an airborne concentration of respirable crystalline silica in excess of 50 µg/m 3, calculated as an 8-hour TWA.
The employer shall assess the exposure of each employee who is or may reasonably be expected to be exposed to respirable crystalline silica at or above the action level in accordance with either the performance option in paragraph (d)(2) or the scheduled monitoring option in paragraph (d)(3) of this section.
The employer shall assess the 8-hour TWA exposure for each employee on the basis of any combination of air monitoring data or objective data sufficient to accurately characterize employee exposures to respirable crystalline silica.
The employer shall reassess exposures whenever a change in the production, process, control equipment, personnel, or work practices may reasonably be expected to result in new or additional exposures at or above the action level, or when the employer has any reason to believe that new or additional exposures at or above the action level have occurred.
The employer shall ensure that all samples taken to satisfy the monitoring requirements of paragraph (d) of this section are evaluated by a laboratory that analyzes air samples for respirable crystalline silica in accordance with the procedures in Appendix A to this section.
The employer shall establish a regulated area wherever an employee's exposure to airborne concentrations of respirable crystalline silica is, or can reasonably be expected to be, in excess of the PEL.
The employer shall limit access to regulated areas to:
The employer shall provide each employee and the employee's designated representative entering a regulated area with an appropriate respirator in accordance with paragraph (g) of this section and shall require each employee and the employee's designated representative to use the respirator while in a regulated area.
The employer shall use engineering and work practice controls to reduce and maintain employee exposure to respirable crystalline silica to or below the PEL, unless the employer can demonstrate that such controls are not feasible. Wherever such feasible engineering and work practice controls are not sufficient to reduce employee exposure to or below the PEL, the employer shall nonetheless use them to reduce employee exposure to the lowest feasible level and shall supplement them with the use of respiratory protection that complies with the requirements of paragraph (g) of this section.
In addition to the requirements of paragraph (f)(1) of this section, the employer shall comply with other OSHA standards, when applicable, such as 29 CFR 1910.94 (Ventilation), 29 CFR 1915.34 (Mechanical paint removers), and 29 CFR 1915 Subpart I (Personal Protective Equipment), where abrasive blasting is conducted using crystalline silica-containing blasting agents, or where abrasive blasting is conducted on substrates that contain crystalline silica.
Where respiratory protection is required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph and 29 CFR 1910.134. Respiratory protection is required:
Where respirator use is required by this section, the employer shall institute a respiratory protection program in accordance with 29 CFR 1910.134.
The employer shall make available an initial (baseline) medical examination within 30 days after initial assignment, unless the employee has received a medical examination that meets the requirements of this section within the last three years. The examination shall consist of:
The employer shall make available medical examinations that include the procedures described in paragraph (i)(2) of this section (except paragraph (i)(2)(v)) at least every three years, or more frequently if recommended by the PLHCP.
The employer shall ensure that the examining PLHCP has a copy of this standard, and shall provide the PLHCP with the following information:
The employer shall ensure that the PLHCP explains to the employee the results of the medical examination and provides each employee with a written medical report within 30 days of each medical examination performed. The written report shall contain:
The employer shall include respirable crystalline silica in the program established to comply with the hazard communication standard (HCS) (29 CFR 1910.1200). The employer shall ensure that each employee has access to labels on containers of crystalline silica and safety data sheets, and is trained in accordance with the provisions of HCS and paragraph (j)(3) of this section. The employer shall ensure that at least the following hazards are addressed: Cancer, lung effects, immune system effects, and kidney effects.
The employer shall post signs at all entrances to regulated areas that bear the following legend:
DANGER
RESPIRABLE CRYSTALLINE SILICA
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
Appendix A to § 1910.1053—Methods of Sample Analysis
This appendix specifies the procedures for analyzing air samples for respirable crystalline silica, as well as the quality control procedures that employers must ensure that laboratories use when performing an analysis required under 29 CFR 1910.1053 (d)(5). Employers must ensure that such a laboratory:
1. Evaluates all samples using the procedures specified in one of the following analytical methods: OSHA ID-142; NMAM 7500; NMAM 7602; NMAM 7603; MSHA P-2; or MSHA P-7;
2. Is accredited to ANS/ISO/IEC Standard 17025:2005 with respect to crystalline silica analyses by a body that is compliant with ISO/IEC Standard 17011:2004 for implementation of quality assessment programs;
3. Uses the most current National Institute of Standards and Technology (NIST) or NIST traceable standards for instrument calibration or instrument calibration verification;
4. Implements an internal quality control (QC) program that evaluates analytical uncertainty and provides employers with estimates of sampling and analytical error;
5. Characterizes the sample material by identifying polymorphs of respirable crystalline silica present, identifies the presence of any interfering compounds that might affect the analysis, and makes any corrections necessary in order to obtain accurate sample analysis; and
6. Analyzes quantitatively for crystalline silica only after confirming that the sample matrix is free of uncorrectable analytical interferences, corrects for analytical interferences, and uses a method that meets the following performance specifications:
6.1 Each day that samples are analyzed, performs instrument calibration checks with standards that bracket the sample concentrations;
6.2 Uses five or more calibration standard levels to prepare calibration curves and ensures that standards are distributed through the calibration range in a manner that accurately reflects the underlying calibration curve; and
6.3 Optimizes methods and instruments to obtain a quantitative limit of detection that represents a value no higher than 25 percent of the PEL based on sample air volume.
Appendix B to § 1910.1053—Medical Surveillance Guidelines
Introduction
The purpose of this Appendix is to provide medical information and recommendations to aid physicians and other licensed health care professionals (PLHCPs) regarding compliance with the medical surveillance provisions of the respirable crystalline silica standard (29 CFR 1910.1053). Appendix B is for informational and guidance purposes only and none of the statements in Appendix B should be construed as imposing a mandatory requirement on employers that is not otherwise imposed by the standard.
Medical screening and surveillance allow for early identification of exposure-related health effects in individual employee and groups of employees, so that actions can be taken to both avoid further exposure and prevent or address adverse health outcomes. Silica-related diseases can be fatal, encompass a variety of target organs, and may have public health consequences when considering the increased risk of a latent tuberculosis (TB) infection becoming active. Thus, medical surveillance of silica-exposed employees requires that PLHCPs have a thorough knowledge of silica-related health effects.
This Appendix is divided into seven sections. Section 1 reviews silica-related diseases, medical responses, and public health responses. Section 2 outlines the components of the medical surveillance program for employees exposed to silica. Section 3 describes the roles and responsibilities of the PLHCP implementing the program and of other medical specialists and public health professionals. Section 4 provides a discussion of considerations, including confidentiality. Section 5 provides a list of additional resources and Section 6 lists references. Section 7 provides sample forms for the written medical report for the employee, the written medical opinion for the employer and the written authorization.
1. Recognition of Silica-Related Diseases
1.1. Overview. The term “silica” refers specifically to the compound silicon dioxide (SiO2). Silica is a major component of sand, rock, and mineral ores. Exposure to fine (respirable size) particles of crystalline forms of silica is associated with adverse health effects, such as silicosis, lung cancer, chronic obstructive pulmonary disease (COPD), and activation of latent TB infections. Exposure to respirable crystalline silica can occur in industry settings such as foundries, abrasive blasting operations, paint manufacturing, glass and concrete product manufacturing, brick making, china and pottery manufacturing, manufacturing of plumbing fixtures, and many construction activities including highway repair, masonry, concrete work, rock drilling, and tuck-pointing. New uses of silica continue to emerge. These include countertop manufacturing, finishing, and installation (Kramer et al. 2012; OSHA 2015) and hydraulic fracturing in the oil and gas industry (OSHA 2012).
Silicosis is an irreversible, often disabling, and sometimes fatal fibrotic lung disease. Progression of silicosis can occur despite removal from further exposure. Diagnosis of silicosis requires a history of exposure to silica and radiologic findings characteristic of silica exposure. Three different presentations of silicosis (chronic, accelerated, and acute) have been defined. Accelerated and acute silicosis are much less common than chronic silicosis. However, it is critical to recognize all cases of accelerated and acute silicosis because these are life-threatening illnesses and because they are caused by substantial overexposures to respirable crystalline silica. Although any case of silicosis indicates a breakdown in prevention, a case of acute or accelerated silicosis implies current high exposure and a very marked breakdown in prevention.
In addition to silicosis, employees exposed to respirable crystalline silica, especially those with accelerated or acute silicosis, are at increased risks of contracting active TB and other infections (ATS 1997; Rees and Murray 2007). Exposure to respirable crystalline silica also increases an employee's risk of developing lung cancer, and the higher the cumulative exposure, the higher the risk (Steenland et al. 2001; Steenland and Ward 2014). Symptoms for these diseases and other respirable crystalline silica-related diseases are discussed below.
1.2. Chronic Silicosis. Chronic silicosis is the most common presentation of silicosis and usually occurs after at least 10 years of exposure to respirable crystalline silica. The clinical presentation of chronic silicosis is:
1.2.1. Symptoms—shortness of breath and cough, although employees may not notice any symptoms early in the disease. Constitutional symptoms, such as fever, loss of appetite and fatigue, may indicate other diseases associated with silica exposure, such as TB infection or lung cancer. Employees with these symptoms should immediately receive further evaluation and treatment.
1.2.2. Physical Examination—may be normal or disclose dry rales or rhonchi on lung auscultation.
1.2.3. Spirometry—may be normal or may show only a mild restrictive or obstructive pattern.
1.2.4. Chest X-ray—classic findings are small, rounded opacities in the upper lung fields bilaterally. However, small irregular opacities and opacities in other lung areas can also occur. Rarely, “eggshell calcifications” in the hilar and mediastinal lymph nodes are seen.
1.2.5. Clinical Course—chronic silicosis in most cases is a slowly progressive disease. Under the respirable crystalline silica standard, the PLHCP is to recommend that employees with a 1/0 category X-ray be referred to an American Board Certified Specialist in Pulmonary Disease or Occupational Medicine. The PLHCP and/or Specialist should counsel employees regarding work practices and personal habits that could affect employees' respiratory health.
1.3. Accelerated Silicosis. Accelerated silicosis generally occurs within 5-10 years of exposure and results from high levels of exposure to respirable crystalline silica. The clinical presentation of accelerated silicosis is:
1.3.1. Symptoms—shortness of breath, cough, and sometimes sputum production. Employees with exposure to respirable crystalline silica, and especially those with accelerated silicosis, are at high risk for activation of TB infections, atypical mycobacterial infections, and fungal superinfections. Constitutional symptoms, such as fever, weight loss, hemoptysis (coughing up blood), and fatigue may herald one of these infections or the onset of lung cancer.
1.3.2. Physical Examination—rales, rhonchi, or other abnormal lung findings in relation to illnesses present. Clubbing of the digits, signs of heart failure, and cor pulmonale may be present in severe lung disease.
1.3.3. Spirometry—restrictive or mixed restrictive/obstructive pattern.
1.3.4. Chest X-ray—small rounded and/or irregular opacities bilaterally. Large opacities and lung abscesses may indicate infections, lung cancer, or progression to complicated silicosis, also termed progressive massive fibrosis.
1.3.5. Clinical Course—accelerated silicosis has a rapid, severe course. Under the respirable crystalline silica standard, the PLHCP can recommend referral to a Board Certified Specialist in either Pulmonary Disease or Occupational Medicine, as deemed appropriate, and referral to a Specialist is recommended whenever the diagnosis of accelerated silicosis is being considered.
1.4. Acute Silicosis. Acute silicosis is a rare disease caused by inhalation of extremely high levels of respirable crystalline silica particles. The pathology is similar to alveolar proteinosis with lipoproteinaceous material accumulating in the alveoli. Acute silicosis develops rapidly, often, within a few months to less than 2 years of exposure, and is almost always fatal. The clinical presentation of acute silicosis is as follows:
1.4.1. Symptoms—sudden, progressive, and severe shortness of breath. Constitutional symptoms are frequently present and include fever, weight loss, fatigue, productive cough, hemoptysis (coughing up blood), and pleuritic chest pain.
1.4.2. Physical Examination—dyspnea at rest, cyanosis, decreased breath sounds, inspiratory rales, clubbing of the digits, and fever.
1.4.3. Spirometry—restrictive or mixed restrictive/obstructive pattern.
1.4.4. Chest X-ray—diffuse haziness of the lungs bilaterally early in the disease. As the disease progresses, the “ground glass” appearance of interstitial fibrosis will appear.
1.4.5. Clinical Course—employees with acute silicosis are at especially high risk of TB activation, nontuberculous mycobacterial infections, and fungal superinfections. Acute silicosis is immediately life-threatening. The employee should be urgently referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for evaluation and treatment. Although any case of silicosis indicates a breakdown in prevention, a case of acute or accelerated silicosis implies a profoundly high level of silica exposure and may mean that other employees are currently exposed to dangerous levels of silica.
1.5. COPD. COPD, including chronic bronchitis and emphysema, has been documented in silica-exposed employees, including those who do not develop silicosis. Periodic spirometry tests are performed to evaluate each employee for progressive changes consistent with the development of COPD. In addition to evaluating spirometry results of individual employees over time, PLHCPs may want to be aware of general trends in spirometry results for groups of employees from the same workplace to identify possible problems that might exist at that workplace. ( See Section 2 of this Appendix on Medical Surveillance for further discussion.) Heart disease may develop secondary to lung diseases such as COPD. A recent study by Liu et al. 2014 noted a significant exposure-response trend between cumulative silica exposure and heart disease deaths, primarily due to pulmonary heart disease, such as cor pulmonale.
1.6. Renal and Immune System. Silica exposure has been associated with several types of kidney disease, including glomerulonephritis, nephrotic syndrome, and end stage renal disease requiring dialysis. Silica exposure has also been associated with other autoimmune conditions, including progressive systemic sclerosis, systemic lupus erythematosus, and rheumatoid arthritis. Studies note an association between employees with silicosis and serologic markers for autoimmune diseases, including antinuclear antibodies, rheumatoid factor, and immune complexes (Jalloul and Banks 2007; Shtraichman et al. 2015).
1.7. TB and Other Infections. Silica-exposed employees with latent TB are 3 to 30 times more likely to develop active pulmonary TB infection (ATS 1997; Rees and Murray 2007). Although respirable crystalline silica exposure does not cause TB infection, individuals with latent TB infection are at increased risk for activation of disease if they have higher levels of respirable crystalline silica exposure, greater profusion of radiographic abnormalities, or a diagnosis of silicosis. Demographic characteristics, such as immigration from some countries, are associated with increased rates of latent TB infection. PLHCPs can review the latest Centers for Disease Control and Prevention (CDC) information on TB incidence rates and high risk populations online ( See Section 5 of this Appendix). Additionally, silica-exposed employees are at increased risk for contracting nontuberculous mycobacterial infections, including Mycobacterium avium-intracellulare and Mycobacterium kansaii.
1.8. Lung Cancer. The National Toxicology Program has listed respirable crystalline silica as a known human carcinogen since 2000 (NTP 2014). The International Agency for Research on Cancer (2012) has also classified silica as Group 1 (carcinogenic to humans). Several studies have indicated that the risk of lung cancer from exposure to respirable crystalline silica and smoking is greater than additive (Brown 2009; Liu et al. 2013). Employees should be counseled on smoking cessation.
2. Medical Surveillance
PLHCPs who manage silica medical surveillance programs should have a thorough understanding of the many silica-related diseases and health effects outlined in Section 1 of this Appendix. At each clinical encounter, the PLHCP should consider silica-related health outcomes, with particular vigilance for acute and accelerated silicosis. In this Section, the required components of medical surveillance under the respirable crystalline silica standard are reviewed, along with additional guidance and recommendations for PLHCPs performing medical surveillance examinations for silica-exposed employees.
2.1. History
2.1.1. The respirable crystalline silica standard requires the following: A medical and work history, with emphasis on: Past, present, and anticipated exposure to respirable crystalline silica, dust, and other agents affecting the respiratory system; any history of respiratory system dysfunction, including signs and symptoms of respiratory disease (e.g., shortness of breath, cough, wheezing); history of TB; and smoking status and history.
2.1.2. Further, the employer must provide the PLHCP with the following information:
2.1.2.1. A description of the employee's former, current, and anticipated duties as they relate to the employee's occupational exposure to respirable crystalline silica;
2.1.2.2. The employee's former, current, and anticipated levels of occupational exposure to respirable crystalline silica;
2.1.2.3. A description of any personal protective equipment used or to be used by the employee, including when and for how long the employee has used or will use that equipment; and
2.1.2.4. Information from records of employment-related medical examinations previously provided to the employee and currently within the control of the employer.
2.1.3. Additional guidance and recommendations: A history is particularly important both in the initial evaluation and in periodic examinations. Information on past and current medical conditions (particularly a history of kidney disease, cardiac disease, connective tissue disease, and other immune diseases), medications, hospitalizations and surgeries may uncover health risks, such as immune suppression, that could put an employee at increased health risk from exposure to silica. This information is important when counseling the employee on risks and safe work practices related to silica exposure.
2.2. Physical Examination
2.2.1. The respirable crystalline silica standard requires the following: A physical examination, with special emphasis on the respiratory system. The physical examination must be performed at the initial examination and every three years thereafter.
2.2.2. Additional guidance and recommendations: Elements of the physical examination that can assist the PHLCP include: An examination of the cardiac system, an extremity examination (for clubbing, cyanosis, edema, or joint abnormalities), and an examination of other pertinent organ systems identified during the history.
2.3. TB Testing
2.3.1. The respirable crystalline silica standard requires the following: Baseline testing for TB on initial examination.
2.3.2. Additional guidance and recommendations:
2.3.2.1. Current CDC guidelines ( See Section 5 of this Appendix) should be followed for the application and interpretation of Tuberculin skin tests (TST). The interpretation and documentation of TST reactions should be performed within 48 to 72 hours of administration by trained PLHCPs.
2.3.2.2. PLHCPs may use alternative TB tests, such as interferon-γ release assays (IGRAs), if sensitivity and specificity are comparable to TST (Mazurek et al. 2010; Slater et al. 2013). PLHCPs can consult the current CDC guidelines for acceptable tests for latent TB infection.
2.3.2.3. The silica standard allows the PLHCP to order additional tests or test at a greater frequency than required by the standard, if deemed appropriate. Therefore, PLHCPs might perform periodic (e.g., annual) TB testing as appropriate, based on employees' risk factors. For example, according to the American Thoracic Society (ATS), the diagnosis of silicosis or exposure to silica for 25 years or more are indications for annual TB testing (ATS 1997). PLHCPs should consult the current CDC guidance on risk factors for TB ( See Section 5 of this Appendix).
2.3.2.4. Employees with positive TB tests and those with indeterminate test results should be referred to the appropriate agency or specialist, depending on the test results and clinical picture. Agencies, such as local public health departments, or specialists, such as a pulmonary or infectious disease specialist, may be the appropriate referral. Active TB is a nationally notifiable disease. PLHCPs should be aware of the reporting requirements for their region. All States have TB Control Offices that can be contacted for further information. ( See Section 5 of this Appendix for links to CDC's TB resources and State TB Control Offices.)
2.3.2.5. The following public health principles are key to TB control in the U.S. (ATS-CDC-IDSA 2005):
2.4. Pulmonary Function Testing
2.4.1. The respirable crystalline silica standard requires the following: Pulmonary function testing must be performed on the initial examination and every three years thereafter. The required pulmonary function test is spirometry and must include forced vital capacity (FVC), forced expiratory volume in one second (FEV 1 ), and FEV 1 /FVC ratio. Testing must be administered by a spirometry technician with a current certificate from a National Institute for Occupational Health and Safety (NIOSH)-approved spirometry course.
2.4.2. Additional guidance and recommendations: Spirometry provides information about individual respiratory status and can be used to track an employee's respiratory status over time or as a surveillance tool to follow individual and group respiratory function. For quality results, the ATS and the American College of Occupational and Environmental Medicine (ACOEM) recommend use of the third National Health and Nutrition Examination Survey (NHANES III) values, and ATS publishes recommendations for spirometry equipment (Miller et al. 2005; Townsend 2011; Redlich et al. 2014). OSHA's publication, Spirometry Testing in Occupational Health Programs: Best Practices for Healthcare Professionals, provides helpful guidance (See Section 5 of this Appendix). Abnormal spirometry results may warrant further clinical evaluation and possible recommendations for limitations on the employee's exposure to respirable crystalline silica.
2.5. Chest X-ray
2.5.1. The respirable crystalline silica standard requires the following: A single posteroanterior (PA) radiographic projection or radiograph of the chest at full inspiration recorded on either film (no less than 14 x 17 inches and no more than 16 x 17 inches) or digital radiography systems. A chest X-ray must be performed on the initial examination and every three years thereafter. The chest X-ray must be interpreted and classified according to the International Labour Office (ILO) International Classification of Radiographs of Pneumoconioses by a NIOSH-certified B Reader.
Chest radiography is necessary to diagnose silicosis, monitor the progression of silicosis, and identify associated conditions such as TB. If the B reading indicates small opacities in a profusion of 1/0 or higher, the employee is to receive a recommendation for referral to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine.
2.5.2. Additional guidance and recommendations: Medical imaging has largely transitioned from conventional film-based radiography to digital radiography systems. The ILO Guidelines for the Classification of Pneumoconioses has historically provided film-based chest radiography as a referent standard for comparison to individual exams. However, in 2011, the ILO revised the guidelines to include a digital set of referent standards that were derived from the prior film-based standards. To assist in assuring that digitally-acquired radiographs are at least as safe and effective as film radiographs, NIOSH has prepared guidelines, based upon accepted contemporary professional recommendations ( See Section 5 of this Appendix). Current research from Laney et al. 2011 and Halldin et al. 2014 validate the use of the ILO digital referent images. Both studies conclude that the results of pneumoconiosis classification using digital references are comparable to film-based ILO classifications. Current ILO guidance on radiography for pneumoconioses and B-reading should be reviewed by the PLHCP periodically, as needed, on the ILO or NIOSH Web sites ( See Section 5 of this Appendix).
2.6. Other Testing. Under the respirable crystalline silica standards, the PLHCP has the option of ordering additional testing he or she deems appropriate. Additional tests can be ordered on a case-by-case basis depending on individual signs or symptoms and clinical judgment. For example, if an employee reports a history of abnormal kidney function tests, the PLHCP may want to order a baseline renal function tests (e.g., serum creatinine and urinalysis). As indicated above, the PLHCP may order annual TB testing for silica-exposed employees who are at high risk of developing active TB infections. Additional tests that PLHCPs may order based on findings of medical examinations include, but is not limited to, chest computerized tomography (CT) scan for lung cancer or COPD, testing for immunologic diseases, and cardiac testing for pulmonary-related heart disease, such as cor pulmonale.
3. Roles and Responsibilities
3.1. PLHCP. The PLHCP designation refers to “an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required” by the respirable crystalline silica standard. The legally permitted scope of practice for the PLHCP is determined by each State. PLHCPs who perform clinical services for a silica medical surveillance program should have a thorough knowledge of respirable crystalline silica-related diseases and symptoms. Suspected cases of silicosis, advanced COPD, or other respiratory conditions causing impairment should be promptly referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine.
Once the medical surveillance examination is completed, the employer must ensure that the PLHCP explains to the employee the results of the medical examination and provides the employee with a written medical report within 30 days of the examination. The written medical report must contain a statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment. In addition, the PLHCP's written medical report must include any recommended limitations on the employee's use of respirators, any recommended limitations on the employee's exposure to respirable crystalline silica, and a statement that the employee should be examined by a Board Certified Specialist in Pulmonary Disease or Occupational medicine if the chest X-ray is classified as 1/0 or higher by the B Reader, or if referral to a Specialist is otherwise deemed appropriate by the PLHCP.
The PLHCP should discuss all findings and test results and any recommendations regarding the employee's health, worksite safety and health practices, and medical referrals for further evaluation, if indicated. In addition, it is suggested that the PLHCP offer to provide the employee with a complete copy of their examination and test results, as some employees may want this information for their own records or to provide to their personal physician or a future PLHCP. Employees are entitled to access their medical records.
Under the respirable crystalline silica standard, the employer must ensure that the PLHCP provides the employer with a written medical opinion within 30 days of the employee examination, and that the employee also gets a copy of the written medical opinion for the employer within 30 days. The PLHCP may choose to directly provide the employee a copy of the written medical opinion. This can be particularly helpful to employees, such as construction employees, who may change employers frequently. The written medical opinion can be used by the employee as proof of up-to-date medical surveillance. The following lists the elements of the written medical report for the employee and written medical opinion for the employer. (Sample forms for the written medical report for the employee, the written medical opinion for the employer, and the written authorization are provided in Section 7 of this Appendix.)
3.1.1. The written medical report for the employee must include the following information:
3.1.1.1. A statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment;
3.1.1.2. Any recommended limitations upon the employee's use of a respirator;
3.1.1.3. Any recommended limitations on the employee's exposure to respirable crystalline silica; and
3.1.1.4. A statement that the employee should be examined by a Board Certified Specialist in Pulmonary Disease or Occupational Medicine, where the standard requires or where the PLHCP has determined such a referral is necessary. The standard requires referral to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for a chest X-ray B reading indicating small opacities in a profusion of 1/0 or higher, or if the PHLCP determines that referral to a Specialist is necessary for other silica-related findings.
3.1.2. The PLHCP's written medical opinion for the employer must include only the following information:
3.1.2.1. The date of the examination;
3.1.2.2. A statement that the examination has met the requirements of this section; and
3.1.2.3. Any recommended limitations on the employee's use of respirators.
3.1.2.4. If the employee provides the PLHCP with written authorization, the written opinion for the employer shall also contain either or both of the following:
3.1.2.5. In addition to the above referral for abnormal chest X-ray, the PLHCP may refer an employee to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for other findings of concern during the medical surveillance examination if these findings are potentially related to silica exposure.
3.1.2.6. Although the respirable crystalline silica standard requires the employer to ensure that the PLHCP explains the results of the medical examination to the employee, the standard does not mandate how this should be done. The written medical opinion for the employer could contain a statement that the PLHCP has explained the results of the medical examination to the employee.
3.2. Medical Specialists. The silica standard requires that all employees with chest X-ray B readings of 1/0 or higher be referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine. If the employee has given written authorization for the employer to be informed, then the employer shall make available a medical examination by a Specialist within 30 days after receiving the PLHCP's written medical opinion.
3.2.1. The employer must provide the following information to the Board Certified Specialist in Pulmonary Disease or Occupational Medicine:
3.2.1.1. A description of the employee's former, current, and anticipated duties as they relate to the employee's occupational exposure to respirable crystalline silica;
3.2.1.2. The employee's former, current, and anticipated levels of occupational exposure to respirable crystalline silica;
3.2.1.3. A description of any personal protective equipment used or to be used by the employee, including when and for how long the employee has used or will use that equipment; and
3.2.1.4. Information from records of employment-related medical examinations previously provided to the employee and currently within the control of the employer.
3.2.2. The PLHCP should make certain that, with written authorization from the employee, the Board Certified Specialist in Pulmonary Disease or Occupational Medicine has any other pertinent medical and occupational information necessary for the specialist's evaluation of the employee's condition.
3.2.3. Once the Board Certified Specialist in Pulmonary Disease or Occupational Medicine has evaluated the employee, the employer must ensure that the Specialist explains to the employee the results of the medical examination and provides the employee with a written medical report within 30 days of the examination. The employer must also ensure that the Specialist provides the employer with a written medical opinion within 30 days of the employee examination. (Sample forms for the written medical report for the employee, the written medical opinion for the employer and the written authorization are provided in Section 7 of this Appendix.)
3.2.4. The Specialist's written medical report for the employee must include the following information:
3.2.4.1. A statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment;
3.2.4.2. Any recommended limitations upon the employee's use of a respirator; and
3.2.4.3. Any recommended limitations on the employee's exposure to respirable crystalline silica.
3.2.5. The Specialist's written medical opinion for the employer must include the following information:
3.2.5.1. The date of the examination; and
3.2.5.2. Any recommended limitations on the employee's use of respirators.
3.2.5.3. If the employee provides the Board Certified Specialist in Pulmonary Disease or Occupational Medicine with written authorization, the written medical opinion for the employer shall also contain any recommended limitations on the employee's exposure to respirable crystalline silica.
3.2.5.4. Although the respirable crystalline silica standard requires the employer to ensure that the Board Certified Specialist in Pulmonary Disease or Occupational Medicine explains the results of the medical examination to the employee, the standard does not mandate how this should be done. The written medical opinion for the employer could contain a statement that the Specialist has explained the results of the medical examination to the employee.
3.2.6. After evaluating the employee, the Board Certified Specialist in Pulmonary Disease or Occupational Medicine should provide feedback to the PLHCP as appropriate, depending on the reason for the referral. OSHA believes that because the PLHCP has the primary relationship with the employer and employee, the Specialist may want to communicate his or her findings to the PLHCP and have the PLHCP simply update the original medical report for the employee and medical opinion for the employer. This is permitted under the standard, so long as all requirements and time deadlines are met.
3.3. Public Health Professionals. PLHCPs might refer employees or consult with public health professionals as a result of silica medical surveillance. For instance, if individual cases of active TB are identified, public health professionals from state or local health departments may assist in diagnosis and treatment of individual cases and may evaluate other potentially affected persons, including coworkers. Because silica-exposed employees are at increased risk of progression from latent to active TB, treatment of latent infection is recommended. The diagnosis of active TB, acute or accelerated silicosis, or other silica-related diseases and infections should serve as sentinel events suggesting high levels of exposure to silica and may require consultation with the appropriate public health agencies to investigate potentially similarly exposed coworkers to assess for disease clusters. These agencies include local or state health departments or OSHA. In addition, NIOSH can provide assistance upon request through their Health Hazard Evaluation program. ( See Section 5 of this Appendix)
4. Confidentiality and Other Considerations
The information that is provided from the PLHCP to the employee and employer under the medical surveillance section of OSHA's respirable crystalline silica standard differs from that of medical surveillance requirements in previous OSHA standards. The standard requires two separate written communications, a written medical report for the employee and a written medical opinion for the employer. The confidentiality requirements for the written medical opinion are more stringent than in past standards. For example, the information the PLHCP can (and must) include in his or her written medical opinion for the employer is limited to: The date of the examination, a statement that the examination has met the requirements of this section, and any recommended limitations on the employee's use of respirators. If the employee provides written authorization for the disclosure of any limitations on the employee's exposure to respirable crystalline silica, then the PLHCP can (and must) include that information in the written medical opinion for the employer as well. Likewise, with the employee's written authorization, the PLHCP can (and must) disclose the PLHCP's referral recommendation (if any) as part of the written medical opinion for the employer. However, the opinion to the employer must not include information regarding recommended limitations on the employee's exposure to respirable crystalline silica or any referral recommendations without the employee's written authorization.
The standard also places limitations on the information that the Board Certified Specialist in Pulmonary Disease or Occupational Medicine can provide to the employer without the employee's written authorization. The Specialist's written medical opinion for the employer, like the PLHCP's opinion, is limited to (and must contain): The date of the examination and any recommended limitations on the employee's use of respirators. If the employee provides written authorization, the written medical opinion can (and must) also contain any limitations on the employee's exposure to respirable crystalline silica.
The PLHCP should discuss the implication of signing or not signing the authorization with the employee (in a manner and language that he or she understands) so that the employee can make an informed decision regarding the written authorization and its consequences. The discussion should include the risk of ongoing silica exposure, personal risk factors, risk of disease progression, and possible health and economic consequences. For instance, written authorization is required for a PLHCP to advise an employer that an employee should be referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for evaluation of an abnormal chest X-ray (B-reading 1/0 or greater). If an employee does not sign an authorization, then the employer will not know and cannot facilitate the referral to a Specialist and is not required to pay for the Specialist's examination. In the rare case where an employee is diagnosed with acute or accelerated silicosis, co-workers are likely to be at significant risk of developing those diseases as a result of inadequate controls in the workplace. In this case, the PLHCP and/or Specialist should explain this concern to the affected employee and make a determined effort to obtain written authorization from the employee so that the PLHCP and/or Specialist can contact the employer.
Finally, without written authorization from the employee, the PLHCP and/or Board Certified Specialist in Pulmonary Disease or Occupational Medicine cannot provide feedback to an employer regarding control of workplace silica exposure, at least in relation to an individual employee. However, the regulation does not prohibit a PLHCP and/or Specialist from providing an employer with general recommendations regarding exposure controls and prevention programs in relation to silica exposure and silica-related illnesses, based on the information that the PLHCP receives from the employer such as employees' duties and exposure levels. Recommendations may include increased frequency of medical surveillance examinations, additional medical surveillance components, engineering and work practice controls, exposure monitoring and personal protective equipment. For instance, more frequent medical surveillance examinations may be a recommendation to employers for employees who do abrasive blasting with silica because of the high exposures associated with that operation.
ACOEM's Code of Ethics and discussion is a good resource to guide PLHCPs regarding the issues discussed in this section ( See Section 5 of this Appendix).
5. Resources
5.1. American College of Occupational and Environmental Medicine (ACOEM):
http://www.acoem.org/codeofconduct.aspx
J Occup Environ Med,
5.2. Center for Disease Control and Prevention (CDC)
http://www.cdc.gov/tb/default.htm
http://www.cdc.gov/tb/links/tboffices.htm
http://www.cdc.gov/tb/programs/laws/default.htm
http://www.cdc.gov/tb/publications/ltbi/pdf/targetedltbi.pdf
5.3. International Labour Organization
http://www.ilo.org/safework/info/publications/WCMS_168260/lang-en/index.htm
5.4. National Institute of Occupational Safety and Health (NIOSH)
http://www.cdc.gov/niosh/topics/chestradiography/breader-info.html
http://www.cdc.gov/niosh/docs/2011-198/.
http://www.cdc.gov/niosh/docs/2002-129/
http://www.cdc.gov/niosh/hhe/
5.5. National Industrial Sand Association:
http://www.sand.org/silica-occupational-health-program
5.6. Occupational Safety and Health Administration (OSHA)
http://www.osha.gov/html/Feed_Back.html
http://www.osha.gov/dts/oom/clinicians/index.html
http://www.osha.gov/dsg/topics/silicacrystalline/index.html
http://www.osha.gov/Publications/OSHA3637.pdf
http://www.osha.gov/Publications/osha3415.pdf
http://www.osha.gov/Publications/osha3418.pdf
5.7. Other
CA Cancer J Clin,
6. References
Am J Respir Crit Care Med,
Morbidity and Mortality Weekly Report (MMWR),
http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5412a1.htm.
Occupational Medicine,
Acad Radiol,
International Agency for Research on Cancer. (2012). Monographs on the evaluation of carcinogenic risks to humans: Arsenic, Metals, Fibers, and Dusts Silica Dust, Crystalline, in the Form of Quartz or Cristobalite. A Review of Human Carcinogens. Volume 100 C. Geneva, Switzerland: World Health Organization.
Jalloul, A.S. and Banks D.E. (2007). Chapter 23. The health effects of silica exposure. In: Rom, W.N. and Markowitz, S.B. (Eds). Environmental and Occupational Medicine, 4th edition. Lippincott, Williams and Wilkins, Philadelphia, 365-387.
Chest,
Chest,
Am J Epi,
Epidemiology,
Morbidity and Mortality Weekly Report (MMWR),
Miller, M.R., Hankinson, J., Brusasco, V., Burgos, F., Casaburi, R., Coates, A., Crapo, R., Enright, P., van der Grinten, C.P., Gustafsson, P., Jensen, R., Johnson, D.C., MacIntyre, N., McKay, R., Navajas, D., Pedersen, O.F., Pellegrino, R., Viegi, G., and Wanger, J. (2005).
Eur Respir J,
http://ntp.niehs.nih.gov/ntp/roc/content/profiles/silica.pdf.
Occupational Safety and Health Administration/National Institute for Occupational Safety and Health (OSHA/NIOSH) (2012). Hazard Alert. Worker exposure to silica during hydraulic fracturing.
Occupational Safety and Health Administration/National Institute for Occupational Safety and Health (OSHA/NIOSH) (2015). Hazard alert. Worker exposure to silica during countertop manufacturing, finishing, and installation. (OSHA-HA-3768-2015).
Am J Respir Crit Care Med
Int J Tuberc Lung Dis
Occup Med,
Am J Respir Crit Care Med,
Cancer Causes Control,
CA Cancer J Clin,
J Occup Environ Med,
7. Sample Forms
Three sample forms are provided. The first is a sample written medical report for the employee. The second is a sample written medical opinion for the employer. And the third is a sample written authorization form that employees sign to clarify what information the employee is authorizing to be released to the employer.
[81 FR 16862, Mar. 25, 2016]
| Neutron energy (million electron volts (Mev)) | Number of neutrons per square centimeter equivalent to a dose of 1 rem (neutrons/cm 2 ) | Average flux to deliver 100 millirem in 40 hours (neutrons/cm 2 per sec.) |
|---|---|---|
| Thermal | 970 × 10 6 | 670 |
| 0.0001 | 720 × 10 6 | 500 |
| 0.005 | 820 × 10 6 | 570 |
| 0.02 | 400 × 10 6 | 280 |
| 0.1 | 120 × 10 6 | 80 |
| 0.5 | 43 × 10 6 | 30 |
| 1.0 | 26 × 10 6 | 18 |
| 2.5 | 29 × 10 6 | 20 |
| 5.0 | 26 × 10 6 | 18 |
| 7.5 | 24 × 10 6 | 17 |
| 10 | 24 × 10 6 | 17 |
| 10 to 30 | 14 × 10 6 | 10 |
| Rems per calendar quarter | |
|---|---|
| Whole body: Head and trunk; active blood-forming organs; lens of eyes; or gonads | 1 1 ⁄ 4 |
| Hands and forearms; feet and ankles | 18 3 ⁄ 4 |
| Skin of whole body | 7 1 ⁄ 2 |
Each radiation area shall be conspicuously posted with a sign or signs bearing the radiation caution symbol described in subparagraph (1) of this paragraph and the words:
CAUTION
RADIATION AREA
CAUTION
HIGH RADIATION AREA
CAUTION
AIRBORNE RADIOACTIVITY AREA
CAUTION
RADIOACTIVE MATERIALS
CAUTION
RADIOACTIVE MATERIALS
CAUTION
RADIOACTIVE MATERIALS
CAUTION
RADIOACTIVE MATERIALS
Notwithstanding the provisions of paragraph (e) of this section:
Radioactive materials packaged and labeled in accordance with regulations of the Department of Transportation published in 49 CFR Chapter I, are exempt from the labeling and posting requirements of this subpart during shipment, provided that the inside containers are labeled in accordance with the provisions of paragraph (e) of this section.
Radioactive materials stored in a nonradiation area shall be secured against unauthorized removal from the place of storage.
No employer shall dispose of radioactive material except by transfer to an authorized recipient, or in a manner approved by the Nuclear Regulatory Commission or a State named in paragraph (p)(3) of this section.
Each employer shall immediately notify the Assistant Secretary of Labor or his duly authorized representative, for employees not protected by the Nuclear Regulatory Commission by means of 10 CFR part 20; paragraph (p)(2) of this section, or the requirements of the laws and regulations of States named in paragraph (p)(3) of this section, by telephone or telegraph of any incident involving radiation which may have caused or threatens to cause:
Each employer shall within 24 hours following its occurrence notify the Assistant Secretary of Labor or his duly authorized representative for employees not protected by the Nuclear Regulatory Commission by means of 10 CFR part 20; paragraph (p)(2) of this section, or the requirements of the laws and applicable regulations of States named in paragraph (p)(3) of this section, by telephone or telegraph of any incident involving radiation which may have caused or threatens to cause:
Any employer who possesses or uses source material, byproduct material, special nuclear material, or other radiation sources under a contract with the Nuclear Regulatory Commission for the operation of NRC plants and facilities and in accordance with the standards, procedures, and other requirements for radiation protection established by the Commission for such contract pursuant to the Atomic Energy Act of 1954 as amended (42 U.S.C. 2011 et seq. ), shall be deemed to be in compliance with the requirements of this section with respect to such possession and use.
Any employer who possesses or uses source material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of 1954, as amended (42 U.S.C. 2011 et seq. ), and has either registered such sources with, or is operating under a license issued by, a State which has an agreement in effect with the Nuclear Regulatory Commission pursuant to section 274(b) (42 U.S.C. 2021(b)) of the Atomic Energy Act of 1954, as amended, and in accordance with the requirements of that State's laws and regulations shall be deemed to be in compliance with the radiation requirements of this section, insofar as his possession and use of such material is concerned, unless the Secretary of Labor, after conference with the Nuclear Regulatory Commission, shall determine that the State's program for control of these radiation sources is incompatible with the requirements of this section. Such agreements currently are in effect only in the States of Alabama, Arkansas, California, Kansas, Kentucky, Florida, Mississippi, New Hampshire, New York, North Carolina, Texas, Tennessee, Oregon, Idaho, Arizona, Colorado, Louisiana, Nebraska, Washington, Maryland, North Dakota, South Carolina, and Georgia.
Any employer who possesses or uses radiation sources other than source material, byproduct material, or special nuclear material, as defined in the Atomic Energy Act of 1954, as amended (42 U.S.C. 2011 et seq. ), and has either registered such sources with, or is operating under a license issued by a State which has an agreement in effect with the Nuclear Regulatory Commission pursuant to section 274(b) (42 U.S.C. 2021(b)) of the Atomic Energy Act of 1954, as amended, and in accordance with the requirements of that State's laws and regulations shall be deemed to be in compliance with the radiation requirements of this section, insofar as his possession and use of such material is concerned, provided the State's program for control of these radiation sources is the subject of a currently effective determination by the Assistant Secretary of Labor that such program is compatible with the requirements of this section. Such determinations currently are in effect only in the States of Alabama, Arkansas, California, Kansas, Kentucky, Florida, Mississippi, New Hampshire, New York, North Carolina, Texas, Tennessee, Oregon, Idaho, Arizona, Colorado, Louisiana, Nebraska, Washington, Maryland, North Dakota, South Carolina, and Georgia.
[39 FR 23502, June 27, 1974, as amended at 43 FR 49746, Oct. 24, 1978; 43 FR 51759, Nov. 7, 1978; 49 FR 18295, Apr. 30, 1984; 58 FR 35309, June 30, 1993. Redesignated at 61 FR 31430, June 20, 1996]
Article means a manufactured item other than a fluid or particle:
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Bulk shipment means any hazardous chemical transported where the mode of transportation comprises the immediate container ( i.e. contained in tanker truck, rail car, or intermodal container).
Chemical means any substance, or mixture of substances.
Chemical manufacturer means an employer with a workplace where chemical(s) are produced for use or distribution.
Chemical name means the scientific designation of a chemical in accordance with the nomenclature system developed by the International Union of Pure and Applied Chemistry (IUPAC) or the Chemical Abstracts Service (CAS) rules of nomenclature, or a name that will clearly identify the chemical for the purpose of conducting a hazard classification.
Classification means to identify the relevant data regarding the hazards of a chemical; review those data to ascertain the hazards associated with the chemical; and decide whether the chemical will be classified as hazardous according to the definition of hazardous chemical in this section. In addition, classification for health and physical hazards includes the determination of the degree of hazard, where appropriate, by comparing the data with the criteria for health and physical hazards.
Combustible dust means finely divided solid particulates of a substance or mixture that pose a flash-fire hazard or explosion hazard when dispersed in air or other oxidizing media.
Commercial account means an arrangement whereby a retail distributor sells hazardous chemicals to an employer, generally in large quantities over time and/or at costs that are below the regular retail price.
Common name means any designation or identification such as code name, code number, trade name, brand name or generic name used to identify a chemical other than by its chemical name.
Container means any bag, barrel, bottle, box, can, cylinder, drum, reaction vessel, storage tank, or the like that contains a hazardous chemical. For purposes of this section, pipes or piping systems, and engines, fuel tanks, or other operating systems in a vehicle, are not considered to be containers.
Designated representative means any individual or organization to whom an employee gives written authorization to exercise such employee's rights under this section. A recognized or certified collective bargaining agent shall be treated automatically as a designated representative without regard to written employee authorization.
Director means the Director, National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Distributor means a business, other than a chemical manufacturer or importer, which supplies hazardous chemicals to other distributors or to employers.
Employee means a worker who may be exposed to hazardous chemicals under normal operating conditions or in foreseeable emergencies. Workers such as office workers or bank tellers who encounter hazardous chemicals only in non-routine, isolated instances are not covered.
Employer means a person engaged in a business where chemicals are either used, distributed, or are produced for use or distribution, including a contractor or subcontractor.
Exposure or exposed means that an employee is subjected in the course of employment to a hazardous chemical, and includes potential (e.g., accidental or possible) exposure. “Subjected” in terms of health hazards includes any route of entry (e.g., inhalation, ingestion, skin contact or absorption.)
Foreseeable emergency means any potential occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment which could result in an uncontrolled release of a hazardous chemical into the workplace.
Gas means a substance which
Hazard category means the division of criteria within each hazard class, e.g., oral acute toxicity and flammable liquids include four hazard categories. These categories compare hazard severity within a hazard class and should not be taken as a comparison of hazard categories more generally.
Hazardous chemical means any chemical which is classified as a physical hazard or a health hazard, a simple asphyxiant, combustible dust, or hazard not otherwise classified.
Hazard class means the nature of the physical or health hazards, e.g., flammable solid, carcinogen, oral acute toxicity.
Hazard not otherwise classified (HNOC) means an adverse physical or health effect identified through evaluation of scientific evidence during the classification process that does not meet the specified criteria for the physical and health hazard classes addressed in this section. This does not extend coverage to adverse physical and health effects for which there is a hazard class addressed in this section, but the effect either falls below the cut-off value/concentration limit of the hazard class or is under a GHS hazard category that has not been adopted by OSHA ( e.g., acute toxicity Category 5).
Hazard statement means a statement assigned to a hazard class and category that describes the nature of the hazard(s) of a chemical, including, where appropriate, the degree of hazard.
Health hazard means a chemical which is classified as posing one of the following hazardous effects: acute toxicity (any route of exposure); skin corrosion or irritation; serious eye damage or eye irritation; respiratory or skin sensitization; germ cell mutagenicity; carcinogenicity; reproductive toxicity; specific target organ toxicity (single or repeated exposure); or aspiration hazard. The criteria for determining whether a chemical is classified as a health hazard are detailed in appendix A to § 1910.1200—Health Hazard Criteria.
Immediate outer package means the first package enclosing the container of hazardous chemical.
Immediate use means that the hazardous chemical will be under the control of and used only by the person who transfers it from a labeled container and only within the work shift in which it is transferred.
Importer means the first business with employees within the Customs Territory of the United States which receives hazardous chemicals produced in other countries for the purpose of supplying them to distributors or employers within the United States.
Label means an appropriate group of written, printed or graphic information elements concerning a hazardous chemical that is affixed to, printed on, or attached to the immediate container of a hazardous chemical, or to the outside packaging.
Label elements means the specified pictogram, hazard statement, signal word and precautionary statement for each hazard class and category.
Liquid means a substance or mixture which at 122 °F (50 °C) has a vapor pressure of not more than 43.51 PSI (300 kPa (3 bar)), which is not completely gaseous at 68 °F (20 °C) and at a standard pressure of 14.69 PSI (101.3 kPa), and which has a melting point or initial melting point of 68 °F (20 °C) or less at a standard pressure of 14.69 PSI (101.3 kPa). Either ASTM D 4359-90 (R2019) (incorporated by reference, see § 1910.6); or the test for determining fluidity (penetrometer test) prescribed in section 2.3.4 of ADR 2019 (incorporated by reference, see § 1910.6) can establish whether a viscous substance or mixture is a liquid if a specific melting point cannot be determined.
Mixture means a combination or a solution composed of two or more substances in which they do not react.
Physical hazard means a chemical that is classified as posing one of the following hazardous effects: explosive, flammable (gases, liquids, or solids); aerosols; chemical under pressure; oxidizer (gases, liquids, or solids); self-reactive; pyrophoric (liquid or solid); self-heating; organic peroxide; corrosive to metal; gas under pressure; in contact with water emits flammable gas; or desensitized explosive. The criteria for determining whether a chemical is classified as a physical hazard are detailed in appendix B to this section.
Physician or other licensed health care professional (PLHCP) means an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows the individual to independently provide or be delegated the responsibility to provide some or all of the health care services referenced in paragraph (i) of this section.
Pictogram means a composition that may include a symbol plus other graphic elements, such as a border, background pattern, or color, that is intended to convey specific information about the hazards of a chemical. Eight pictograms are designated under this standard for application to a hazard category.
Precautionary statement means a phrase that describes recommended measures that should be taken to minimize or prevent adverse effects resulting from exposure to a hazardous chemical, or improper storage or handling.
Produce means to manufacture, process, formulate, blend, extract, generate, emit, or repackage.
Product identifier means the name or number used for a hazardous chemical on a label or in the SDS. It provides a unique means by which the user can identify the chemical. The product identifier used shall permit cross-references to be made among the list of hazardous chemicals required in the written hazard communication program, the label and the SDS.
Released for shipment means a chemical that has been packaged and labeled in the manner in which it will be distributed or sold.
Responsible party means someone who can provide additional information on the hazardous chemical and appropriate emergency procedures, if necessary.
Safety data sheet (SDS) means written or printed material concerning a hazardous chemical that is prepared in accordance with paragraph (g) of this section.
Signal word means a word used to indicate the relative level of severity of hazard and alert the reader to a potential hazard on the label. The signal words used in this section are “danger” and “warning.” “Danger” is used for the more severe hazards, while “warning” is used for the less severe.
Simple asphyxiant means a substance or mixture that displaces oxygen in the ambient atmosphere, and can thus cause oxygen deprivation in those who are exposed, leading to unconsciousness and death.
Solid means a substance or mixture which does not meet the definitions of liquid or gas.
Specific chemical identity means the chemical name, Chemical Abstracts Service (CAS) Registry Number, or any other information that reveals the precise chemical designation of the substance.
Substance means chemical elements and their compounds in the natural state or obtained by any production process, including any additive necessary to preserve the stability of the product and any impurities deriving from the process used, but excluding any solvent which may be separated without affecting the stability of the substance or changing its composition.
Trade secret means any confidential formula, pattern, process, device, information or compilation of information that is used in an employer's business, and that gives the employer an opportunity to obtain an advantage over competitors who do not know or use it. Appendix E to § 1910.1200—Definition of Trade Secret, sets out the criteria to be used in evaluating trade secrets.
Use means to package, handle, react, emit, extract, generate as a byproduct, or transfer.
Work area means a room or defined space in a workplace where hazardous chemicals are produced or used, and where employees are present.
Workplace means an establishment, job site, or project, at one geographical location containing one or more work areas.
Employers who produce, use, or store hazardous chemicals at a workplace in such a way that the employees of other employer(s) may be exposed (for example, employees of a construction contractor working on-site) shall additionally ensure that the hazard communication programs developed and implemented under this paragraph (e) include the following:
The chemical manufacturer, importer, or distributor shall ensure that each container of hazardous chemicals leaving the workplace is labeled, tagged or marked. Hazards not otherwise classified and hazards identified and classified under (d)(1)(ii) do not have to be addressed on the container. Where the chemical manufacturer, importer, or distributor is required to label, tag or mark the following shall be provided:
address, and U.S. telephone number of the chemical manufacturer, importer, or other responsible party.
Except as provided in paragraphs (f)(7) and (f)(8) of this section, the employer shall ensure that each container of hazardous chemicals in the workplace is labeled, tagged or marked with either:
Employees shall be informed of:
Employee training shall include at least:
This section shall become effective July 19, 2024.
Between May 20, 2024 and the dates specified in paragraphs (j)(2) and (3) of this section, as applicable, chemical manufacturers, importers, distributors, and employers may comply with either this section or § 1910.1200 revised as of July 1, 2023, or both during the transition period.
Appendix A to § 1910.1200—Health Hazard Criteria (Mandatory)
A.0 General Classification Considerations
A.0.1 Classification
A.0.1.1 The term “hazard classification” is used to indicate that only the intrinsic hazardous properties of chemicals are considered. Hazard classification incorporates three steps:
A.0.1.2 For many hazard classes, the criteria are semi-quantitative or qualitative and expert judgment is required to interpret the data for classification purposes.
A.0.1.3 Where impurities, additives or individual constituents of a substance or mixture have been identified and are themselves classified, they should be taken into account during classification if they exceed the cut-off value/concentration limit for a given hazard class.
A.0.2 Available Data, Test Methods and Test Data Quality
A.0.2.1 There is no requirement for testing chemicals.
A.0.2.2 The criteria for determining health hazards are test method neutral, i.e., they do not specify particular test methods, as long as the methods are scientifically validated.
A.0.2.3 The term “scientifically validated” refers to the process by which the reliability and the relevance of a procedure are established for a particular purpose. Any test that determines hazardous properties, which is conducted according to recognized scientific principles, can be used for purposes of a hazard determination for health hazards. Test conditions need to be standardized so that the results are reproducible with a given substance, and the standardized test yields “valid” data for defining the hazard class of concern.
A.0.2.4 Existing test data are acceptable for classifying chemicals, although expert judgment also may be needed for classification purposes.
A.0.2.5 The effect of a chemical on biological systems is influenced, by the physico-chemical properties of the substance and/or ingredients of the mixture and the way in which ingredient substances are biologically available. A chemical need not be classified when it can be shown by conclusive experimental data from scientifically validated test methods that the chemical is not biologically available.
A.0.2.6 For classification purposes, epidemiological data and experience on the effects of chemicals on humans ( e.g., occupational data, data from accident databases) shall be taken into account in the evaluation of human health hazards of a chemical.
A.0.3 Classification Based on Weight of Evidence
A.0.3.1 For some hazard classes, classification results directly when the data satisfy the criteria. For others, classification of a chemical shall be determined on the basis of the total weight of evidence using expert judgment. This means that all available information bearing on the classification of hazard shall be considered together, including the results of valid in vitro tests, relevant animal data, and human experience such as epidemiological and clinical studies and well-documented case reports and observations.
A.0.3.2 The quality and consistency of the data shall be considered. Information on chemicals related to the material being classified shall be considered as appropriate, as well as site of action and mechanism or mode of action study results. Both positive and negative results shall be considered together in a single weight-of-evidence determination.
A.0.3.3 Positive effects which are consistent with the criteria for classification, whether seen in humans or animals, shall normally justify classification. Where evidence is available from both humans and animals and there is a conflict between the findings, the quality and reliability of the evidence from both sources shall be evaluated in order to resolve the question of classification. Reliable, good quality human data shall generally have precedence over other data. However, even well-designed and conducted epidemiological studies may lack a sufficient number of subjects to detect relatively rare but still significant effects, or to assess potentially confounding factors. Therefore, positive results from well-conducted animal studies are not necessarily negated by the lack of positive human experience but require an assessment of the robustness, quality and statistical power of both the human and animal data.
A.0.3.4 Route of exposure, mechanistic information, and metabolism studies are pertinent to determining the relevance of an effect in humans. When such information raises doubt about relevance in humans, a lower classification may be warranted. When there is scientific evidence demonstrating that the mechanism or mode of action is not relevant to humans, the chemical should not be classified.
A.0.3.5 Both positive and negative results are considered together in the weight of evidence determination. However, a single positive study performed according to good scientific principles and with statistically and biologically significant positive results may justify classification.
A.0.4 Considerations for the Classification of Mixtures
A.0.4.1 Except as provided in A.0.4.2, the process of classification of mixtures is based on the following sequence:
A.0.4.2 An exception to the above order or precedence is made for Carcinogenicity, Germ Cell Mutagenicity, and Reproductive Toxicity. For these three hazard classes, mixtures shall be classified based upon information on the ingredient substances, unless on a case-by-case basis, justification can be provided for classifying based upon the mixture as a whole. See A.5, A.6, and A.7 of this section for further information on case-by-case bases.
A.0.4.3 Use of cut-off values/concentration limits
A.0.4.3.1 When classifying an untested mixture based on the hazards of its ingredients, cut-off values/concentration limits for the classified ingredients of the mixture are used for several hazard classes. While the adopted cut-off values/concentration limits adequately identify the hazard for most mixtures, there may be some that contain hazardous ingredients at lower concentrations than the specified cut-off values/concentration limits that still pose an identifiable hazard. There may also be cases where the cut-off value/concentration limit is considerably lower than the established non-hazardous level for an ingredient.
A.0.4.3.2 If the classifier has information that the hazard of an ingredient will be evident ( i.e., it presents a health risk) below the specified cut-off value/concentration limit, the mixture containing that ingredient shall be classified accordingly.
A.0.4.3.3 In exceptional cases, conclusive data may demonstrate that the hazard of an ingredient will not be evident ( i.e., it does not present a health risk) when present at a level above the specified cut-off value/concentration limit(s). In these cases the mixture may be classified according to those data. The data must exclude the possibility that the ingredient will behave in the mixture in a manner that would increase the hazard over that of the pure substance. Furthermore, the mixture must not contain ingredients that would affect that determination.
A.0.4.4 Synergistic or antagonistic effects
When performing an assessment in accordance with these requirements, the evaluator must take into account all available information about the potential occurrence of synergistic effects among the ingredients of the mixture. Lowering classification of a mixture to a less hazardous category on the basis of antagonistic effects may be done only if the determination is supported by sufficient data.
A.0.5 Bridging Principles for the Classification of Mixtures Where Test Data Are Not Available for the Complete Mixture
A.0.5.1 Where the mixture itself has not been tested to determine its toxicity, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data shall be used in accordance with the following bridging principles, subject to any specific provisions for mixtures for each hazard class. These principles ensure that the classification process uses the available data to the greatest extent possible in characterizing the hazards of the mixture.
A.0.5.1.1 Dilution
For mixtures classified in accordance with A.1 through A.10 of this Appendix, if a tested mixture is diluted with a diluent that has an equivalent or lower toxicity classification than the least toxic original ingredient, and which is not expected to affect the toxicity of other ingredients, then:
A.0.5.1.2 Batching
For mixtures classified in accordance with A.1 through A.10 of this Appendix, the toxicity of a tested production batch of a mixture can be assumed to be substantially equivalent to that of another untested production batch of the same mixture, when produced by or under the control of the same chemical manufacturer, unless there is reason to believe there is significant variation such that the toxicity of the untested batch has changed. If the latter occurs, a new classification is necessary.
A.0.5.1.3 Concentration of mixtures
For mixtures classified in accordance with A.1, A.2, A.3, A.4, A.8, A.9, or A.10 of this Appendix, if a tested mixture is classified in Category 1, and the concentration of the ingredients of the tested mixture that are in Category 1 is increased, the resulting untested mixture shall be classified in Category 1.
A.0.5.1.4 Interpolation within one hazard category
For mixtures classified in accordance with A.1, A.2, A.3, A.4, A.8, A.9, or A.10 of this Appendix, for three mixtures (A, B and C) with identical ingredients, where mixtures A and B have been tested and are in the same hazard category, and where untested mixture C has the same toxicologically active ingredients as mixtures A and B but has concentrations of toxicologically active ingredients intermediate to the concentrations in mixtures A and B, then mixture C is assumed to be in the same hazard category as A and B.
A.0.5.1.5 Substantially similar mixtures
For mixtures classified in accordance with A.1 through A.10 of this Appendix, given the following set of conditions:
If mixture (i) or (ii) is already classified based on test data, the other mixture can be assigned the same hazard category.
A.0.5.1.6 Aerosols
For mixtures classified in accordance with A.1, A.2, A.3, A.4, A.8, or A.9 of this Appendix, an aerosol form of a mixture shall be classified in the same hazard category as the tested, non-aerosolized form of the mixture, provided the added propellant does not affect the toxicity of the mixture when spraying.
A.1 Acute Toxicity
A.1.1 Definition
Acute toxicity refers to serious adverse health effects ( i.e., lethality) occurring after a single or short-term oral, dermal, or inhalation exposure to a substance or mixture.
A.1.2 Classification Criteria for Substances
A.1.2.1 Substances can be allocated to one of four hazard categories based on acute toxicity by the oral, dermal or inhalation route according to the numeric cut-off criteria as shown in Table A.1.1. Acute toxicity values are expressed as (approximate) LD50 (oral, dermal) or LC 50 (inhalation) values or as acute toxicity estimates (ATE). While some in vivo methods determine LD50/LC50 values directly, other newer in vivo methods ( e.g., using fewer animals) consider other indicators of acute toxicity, such as significant clinical signs of toxicity, which are used by reference to assign the hazard category. See the footnotes following Table A.1.1 for further explanation on the application of these values.
| Exposure route | Category 1 | Category 2 | Category 3 | Category 4 |
|---|---|---|---|---|
| Oral (mg/kg bodyweight) | ATE ≤ 5 | >5 ATE ≤ 50 | >50 ATE ≤ 300 | >300 ATE ≤ 2000 |
| see: Note (a) | ||||
| Note (b) | ||||
| Dermal (mg/kg bodyweight) | ATE ≤ 50 | >50 ATE ≤ 200 | >200 ATE ≤ 1000 | >1000 ATE ≤ 2000 |
| see: Note (a) | ||||
| Note (b) | ||||
| Inhalation—Gases (ppmV) | ATE ≤ 100 | >100 ATE ≤ 500 | >500 ATE ≤ 2500 | >2500 ATE ≤ 20000 |
| see: Note (a) | ||||
| Note (b) | ||||
| Note (c) | ||||
| Inhalation—Vapors (mg/l) | ATE ≤ 0.5 | >0.5 ATE ≤ 2.0 | >2.0 ATE ≤ 10.0 | >10.0 ATE ≤ 20.0 |
| see: Note (a) | ||||
| Note (b) | ||||
| Note (c) | ||||
| Note (d) | ||||
| Inhalation -Dusts and Mists (mg/l) | ATE ≤ 0.05 | >0.05 ATE ≤ 0.5 | >0.5 ATE ≤ 1.0 | >1.0 ATE ≤ 5.0 |
| see: Note (a) | ||||
| Note (b) | ||||
| Note (c) | ||||
| Note: Gas concentrations are expressed in parts per million per volume (ppmV). | ||||
| Notes to table A.1.1: | ||||
| (a) The acute toxicity estimate (ATE) for the classification of a substance is derived using the LD50/LC50 where available; | ||||
| (b) The acute toxicity estimate (ATE) for the classification of a substance or ingredient in a mixture is derived using: | ||||
| (i) the LD 50 /LC 50 where available. Otherwise, | ||||
| (ii) the appropriate conversion value from table 1.2 that relates to the results of a range test, or | ||||
| (iii) the appropriate conversion value from table 1.2 that relates to a classification category; | ||||
| (c) Inhalation cut-off values in the table are based on 4 hour testing exposures. Conversion of existing inhalation toxicity data which has been generated according to 1 hour exposure is achieved by dividing by a factor of 2 for gases and vapors and 4 for dusts and mists; | ||||
| (d) For some substances the test atmosphere will be a vapor which consists of a combination of liquid and gaseous phases. For other substances the test atmosphere may consist of a vapor which is nearly all the gaseous phase. In these latter cases, classification is based on ppmV as follows: Category 1 (100 ppmV), Category 2 (500 ppmV), Category 3 (2500 ppmV), Category 4 (20000 ppmV). | ||||
| The terms “dust”, “mist” and “vapor” are defined as follows: | ||||
| (i) Dust: solid particles of a substance or mixture suspended in a gas (usually air); | ||||
| (ii) Mist: liquid droplets of a substance or mixture suspended in a gas (usually air); | ||||
| (iii) Vapor: the gaseous form of a substance or mixture released from its liquid or solid state. |
A.1.2.3 The preferred test species for evaluation of acute toxicity by the oral and inhalation routes is the rat, while the rat or rabbit are preferred for evaluation of acute dermal toxicity. Test data already generated for the classification of chemicals under existing systems should be accepted when reclassifying these chemicals under the harmonized system. When experimental data for acute toxicity are available in several animal species, scientific judgment should be used in selecting the most appropriate LD 50 value from among scientifically validated tests. In cases where data from human experience ( i.e., occupational data, data from accident databases, epidemiology studies, clinical reports) is also available, it should be considered in a weight of evidence approach consistent with the principles described in A.0.3.
A.1.2.4 In addition to classification for inhalation toxicity, if data are available that indicates that the mechanism of toxicity was corrosivity of the substance or mixture, the classifier must consider if the chemical is corrosive to the respiratory tract. Corrosion of the respiratory tract is defined as destruction of the respiratory tract tissue after a single, limited period of exposure analogous to skin corrosion; this includes destruction of the mucosa. The corrosivity evaluation could be based on expert judgment using such evidence as: human and animal experience, existing ( in vitro ) data, Ph values, information from similar substances or any other pertinent data.
A.1.2.4.1 If the classifier determines the chemical is corrosive to the respiratory tract and data are available that indicate that the effect leads to lethality, then in addition to the appropriate acute toxicity pictogram and hazard statement, the chemical must be labelled with the hazard statement “corrosive to the respiratory tract” and the corrosive pictogram.
A.1.2.4.2 If the classifier determines the chemical is corrosive to the respiratory tract and the effect does not lead to lethality, then the chemical must be addressed in the Specific Target Organ Toxicity hazard classes ( see A.8). If data is insufficient for classification under STOT, but the classifier determines, based on skin or eye data, that the chemical may be corrosive to the respiratory tract, then the hazard must be addressed using data for classification in the skin corrosion/irritation hazard class (see A.2) or Serious Eye Damage/Eye irritation hazard class (see A.3).
A.1.3 Classification Criteria for Mixtures
A.1.3.1 The approach to classification of mixtures for acute toxicity is tiered, and is dependent upon the amount of information available for the mixture itself and for its ingredients. The flow chart of Figure A.1.1 indicates the process that must be followed:
A.1.3.2 Classification of mixtures for acute toxicity may be carried out for each route of exposure, but is only required for one route of exposure as long as this route is followed (estimated or tested) for all ingredients and there is no relevant evidence to suggest acute toxicity by multiple routes. When there is relevant evidence of acute toxicity by multiple routes of exposure, classification is to be conducted for all appropriate routes of exposure. All available information shall be considered. The pictogram and signal word used shall reflect the most severe hazard category; and all relevant hazard statements shall be used.
A.1.3.3 For purposes of classifying the hazards of mixtures in the tiered approach:
A.1.3.4 Classification of mixtures where acute toxicity test data are available for the complete mixture
Where the mixture itself has been tested to determine its acute toxicity, it is classified according to the same criteria as those used for substances, presented in Table A.1.1. If test data for the mixture are not available, the procedures presented below must be followed.
A.1.3.5 Classification of mixtures where acute toxicity test data are not available for the complete mixture: bridging principles
Where the mixture itself has not been tested to determine its acute toxicity, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data will be used in accordance with the following bridging principles as found in paragraph A.0.5 of this Appendix: Dilution, Batching, Concentration of mixtures, Interpolation within one hazard category, Substantially similar mixtures, and Aerosols.
A.1.3.6 Classification of mixtures based on ingredients of the mixture (additivity formula)
A.1.3.6.1 Data available for all ingredients.
The acute toxicity estimate (ATE) of ingredients is considered as follows:
Ingredients that fall within the scope of this paragraph are considered to be ingredients with a known acute toxicity estimate (ATE). See note (b) to Table A.1.1 and paragraph A.1.3.3 for appropriate application of available data to the equation below, and paragraph A.1.3.6.2.4.
The ATE of the mixture is determined by calculation from the ATE values for all relevant ingredients according to the following formula below for oral, dermal or inhalation toxicity:
Where:
i
n ingredients and i is running from 1 to n;
i
A.1.3.6.2 Data are not available for one or more ingredients of the mixture.
A.1.3.6.2.1 Where an ATE is not available for an individual ingredient of the mixture, but available information provides a derived conversion value, the formula in A.1.3.6.1 may be applied. This information may include evaluation of:
A.1.3.6.2.2 This approach requires substantial supplemental technical information, and a highly trained and experienced expert, to reliably estimate acute toxicity. If sufficient information is not available to reliably estimate acute toxicity, proceed to the provisions of A.1.3.6.2.4.
A.1.3.6.2.3 In the event that an ingredient with unknown acute toxicity is used in a mixture at a concentration ≥1%, and the mixture has not been classified based on testing of the mixture as a whole, the mixture cannot be attributed a definitive acute toxicity estimate. In this situation the mixture is classified based on the known ingredients only.
A.1.3.6.2.4 If the total concentration of the relevant ingredient(s) with unknown acute toxicity is ≤10% then the formula presented in A.1.3.6.1 must be used. If the total concentration of the relevant ingredient(s) with unknown acute toxicity is >10%, the formula presented in A.1.3.6.1 is corrected to adjust for the percentage of the unknown ingredient(s) as follows:
| Exposure routes | Classification category or experimentally obtained acute toxicity range estimate | Converted acute toxicity point estimate |
|---|---|---|
| Oral (mg/kg bodyweight) | 0 < Category 1 ≤ 5 | 0.5 |
| 5 < Category 2 ≤ 50 | 5 | |
| 50 < Category 3 ≤ 300 | 100 | |
| 300 < Category 4 ≤ 2000 | 500 | |
| Dermal (mg/kg bodyweight) | 0 < Category 1 ≤ 50 | 5 |
| 50 < Category 2 ≤ 200 | 50 | |
| 200 < Category 3 ≤ 1000 | 300 | |
| 1000 < Category 4 ≤ 2000 | 1100 | |
| Gases (ppmV) | 0 < Category 1 ≤ 100 | 10 |
| 100 < Category 2 ≤ 500 | 100 | |
| 500 < Category 3 ≤ 2500 | 700 | |
| 2500 < Category 4 ≤ 20000 | 4500 | |
| Vapors (mg/l) | 0 < Category 1 ≤ 0.5 | 0.05 |
| 0.5 < Category 2 ≤ 2.0 | 0.5 | |
| 2.0 < Category 3 ≤ 10.0 | 3 | |
| 10.0 < Category 4 ≤ 20.0 | 11 | |
| Dust/mist (mg/l) | 0 < Category 1 ≤ 0.05 | 0.005 |
| 0.05 < Category 2 ≤ 0.5 | 0.05 | |
| 0.5 < Category 3 ≤ 1.0 | 0.5 | |
| 1.0 < Category 4 ≤ 5.0 | 1.5 | |
| Note: Gas concentrations are expressed in parts per million per volume (ppmV). |
A.2 Skin Corrosion/Irritation
A.2.1 Definitions and General Considerations
A.2.1.1 Skin corrosion refers to the production of irreversible damage to the skin; namely, visible necrosis through the epidermis and into the dermis occurring after initial exposure to a substance or mixture.
Skin irritation refers to the production of reversible damage to the skin occurring after initial exposure to a substance or mixture.
A.2.1.2 To classify, all available and relevant information on skin corrosion/irritation is collected and its quality in terms of adequacy and reliability is assessed. Wherever possible classification should be based on data generated using internationally validated and accepted methods, such as OECD Test Guidelines (TG) or equivalent methods. Sections A.2.2.1 to A.2.2.6 provide classification criteria for the different types of information that may be available.
A.2.1.3 A tiered approach (see A.2.2.7) organizes the available information into levels/tiers and provides for decision-making in a structured and sequential manner. Classification results directly when the information consistently satisfies the criteria. However, where the available information gives inconsistent and/or conflicting results within a tier, classification of a substance or a mixture is made on the basis of the weight of evidence within that tier. In some cases when information from different tiers gives inconsistent and/or conflicting results (see A.2.2.7.3) or where data individually are insufficient to conclude on the classification, an overall weight of evidence approach is used (see A.0.3).
A.2.2 Classification Criteria for Substances
Substances shall be allocated to one of the following categories within this hazard class:
This category may be further divided into up to three sub-categories (1A, 1B, and 1C).
Corrosive substances should be classified in Category 1 where data are not sufficient for sub-categorization.
When data are sufficient, substances may be classified in one of the three sub-categories 1A, 1B, or 1C.
A.2.2.1 Classification Based on Standard Human Data
Existing reliable and good quality human data on skin corrosion/irritation should be given high weight for classification. Existing human data could be derived from single or repeated exposure(s), for example in occupational, consumer, transport or emergency response scenarios and epidemiological and clinical studies in well-documented case reports and observations (see A.0.2.6 and A.0.3). Although human data from accident or poison center databases can provide evidence for classification, absence of incidents is not itself evidence for no classification, as exposures are generally unknown or uncertain.
A.2.2.2 Classification Based on Standard Animal Test Data
OECD TG 404 is the currently available internationally validated and accepted animal test for classification as skin corrosive or irritant (See Table A.2.1 and A.2.2) and is the standard animal test. The current version of OECD TG 404 uses a maximum of 3 animals. Results from animal studies conducted under previous versions of OECD TG 404 that used more than 3 animals are also considered standard animal tests.
A.2.2.2.1 Skin Corrosion
A.2.2.2.1.1 A substance is corrosive to the skin when it produces destruction of skin tissue, namely, visible necrosis through the epidermis and into the dermis, in at least one tested animal after initial exposure up to a 4-hour duration.
A.2.2.2.1.2 Three sub-categories of Category 1 are provided in Table A.2.1, all of which shall be regulated as Category 1.
| Criteria | |
|---|---|
| Category 1 | Destruction of skin tissue, namely, visible necrosis through the epidermis and into the dermis, in at least one tested animal after exposure ≤4 h. |
| Sub-category 1A | Corrosive responses in at least one animal following exposure ≤3 min during an observation period ≤1 h. |
| Sub-category 1B | Corrosive responses in at least one animal following exposure >3 min and ≤1 h and observations ≤14 days. |
| Sub-category 1C | Corrosive responses in at least one animal after exposures >1 h and ≤ 4 h and observations ≤14 days. |
| a The use of human data is discussed in A.2.2.1. |
A.2.2.2.2 Skin Irritation
A.2.2.2.2.1 A substance is irritant to skin when it produces reversible damage to the skin following its application for up to 4 hours.
A.2.2.2.2.2 A single irritant category (Category 2) is presented in the Table A.2.2. A substance is irritant to skin, when after the first application, it produces reversible damage to the skin following its application for up to 4 hours. An irritation category (Category 2) is provided that:
A.2.2.2.2.3 Reversibility of skin lesions is another consideration in evaluating irritant responses. When inflammation persists to the end of the observation period in two or more test animals, taking into consideration alopecia (limited area), hyperkeratosis, hyperplasia and scaling, then a chemical should be considered to be an irritant.
A.2.2.2.2.4 Animal irritant responses within a test can be quite variable, as they are with corrosion. A separate irritant criterion accommodates cases when there is a significant irritant response but less than the mean score criterion for a positive test. For example, a substance should be designated as an irritant if at least 1 of 3 tested animals shows a very elevated mean score according to test method used throughout the study, including lesions persisting at the end of an observation period of normally 14 days. Other responses should also fulfil this criterion. However, it should be ascertained that the responses are the result of chemical exposure. Addition of this criterion increases the sensitivity of the classification system.
| Criteria | |
|---|---|
| Irritant (Category 2) | (1) Mean score of ≥2.3 ≤ 4.0 for erythema/eschar or for edema in at least 2 of 3 tested animals from grading at 24, 48, and 72 hours after patch removal or, if reactions are delayed, from grades on 3 consecutive days after the onset of skin reactions; or |
| (2) Inflammation that persists to the end of the observation period normally 14 days in a least 2 animals, particularly taking into account alopecia (limited area), hyperkeratosis, hyperplasia, and scaling; or | |
| (3) In some cases where there is pronounced variability of response among animals, with very distinctive positive effects related to chemical exposure in a single animal but less than the criteria above. | |
| a Grading criteria are understood as described in OECD Test Guideline 404. |
A.2.2.3 Classification Based on In Vitro/Ex Vivo Data
A.2.2.3.1 The currently available individual in vitro/ex vivo test methods address either skin irritation or skin corrosion, but do not address both endpoints in one single test. Therefore, classification based solely on in vitro/ex vivo test results may require data from more than one method.
A.2.2.3.2 Wherever possible classification should be based on data generated using internationally validated and accepted in vitro/ex vivo test methods, and the classification criteria provided in these test methods needs to be applied. In vitro/ex vivo data can only be used for classification when the tested substance is within the applicability domain of the test methods used. Additional limitations described in the published literature should also be taken into consideration.
A.2.2.3.3 Skin corrosion
A.2.2.3.3.1 Where tests have been undertaken in accordance with OECD Test Guidelines (TGs) 430, 431, or 435, a substance is classified for skin corrosion in category 1 (and, where possible and required into sub-categories 1A, 1B, or 1C).
A.2.2.3.3.2 Some in vitro/ex vivo methods do not allow differentiation between sub-categories 1B and 1C. Where existing in vitro/ex vivo data cannot distinguish between the sub-categories, additional information has to be taken into account to differentiate between these two sub-categories. Where no or insufficient additional information is available, category 1 is applied.
A.2.2.3.3.3 A substance identified as not corrosive should be considered for classification as skin irritant.
A.2.2.3.4 Skin irritation
A.2.2.3.4.1 Where a conclusion of corrosivity can be excluded and where tests have been undertaken in accordance with OECD Test Guideline 439, a substance is classified for skin irritation in category 2.
A.2.2.3.4.2 A negative result in an internationally accepted and validated in vitro/ex vivo test for skin irritation, e.g., OECD TG 439, can be used to conclude as not classified for skin irritation.
A.2.2.4 Classification Based on Other, Existing Skin Data in Animals
Other existing skin data in animals may be used for classification, but there may be limitations regarding the conclusions that can be drawn if a substance is highly toxic via the dermal route, an in vivo skin corrosion/irritation study may not have been conducted since the amount of test substance to be applied would considerably exceed the toxic dose and, consequently, would result in the death of the animals. When observations of skin corrosion/irritation in acute toxicity studies are made, these data may be used for classification, provided that the dilutions used and species tested are relevant. Solid substances (powders) may become corrosive or irritant when moistened or in contact with moist skin or mucous membranes. This is generally indicated in the standardized test methods.
A.2.2.5 Classification Based on Chemical Properties
Skin effects may be indicated by pH extremes such as ≤2 and ≥11.5 especially when associated with significant acid/alkaline reserve (buffering capacity). Generally, such substances are expected to produce significant effects on the skin. In the absence of any other information, a substance is considered corrosive (Skin Category 1) if it has a pH ≤2 or a pH ≥11.5. However, if consideration of acid/alkaline reserve suggests the substance may not be corrosive despite the low or high pH, this needs to be confirmed by other data, preferably from an appropriate validated in vitro/ex vivo test. Buffering capacity and pH can be determined by test methods including OECD TG 122.
A.2.2.6 Classification Based on Non-Test Methods
A.2.2.6.1 Classification, including non-classification, can be based on non-test methods, with due consideration of reliability and applicability, on a case-by-case basis. Such methods include computer models predicting qualitative structure-activity relationships (structural alerts, SAR); quantitative structure-activity relationships (QSARs); computer expert systems; and read-across using analogue and category approaches.
A.2.2.6.2 Read-across using analogue or category approaches requires sufficiently reliable test data on similar substance(s) and justification of the similarity of the tested substance(s) with the substance(s) to be classified. Where adequate justification of the read-across approach is provided, it has in general higher weight than (Q)SARs.
A.2.2.6.3 Classification based on (Q)SARs requires sufficient data and validation of the model. The validity of the computer models and the prediction should be assessed using internationally recognized principles for the validation of (Q)SARs. With respect to reliability, lack of alerts in a SAR or expert system is not sufficient evidence for no classification.
A.2.2.7 Classification in a Tiered Approach
A.2.2.7.1 A tiered approach to the evaluation of initial information should be considered, where applicable (Figure A.2.1), recognizing that not all elements may be relevant. However, all available and relevant information of sufficient quality needs to be examined for consistency with respect to the resulting classification.
A.2.2.7.2 In the tiered approach (Figure A.2.1), existing human and animal data form the highest tier, followed by in vitro/ex vivo data, other existing skin data in animals, and then other sources of information. Where information from data within the same tier is inconsistent and/or conflicting, the conclusion from that tier is determined by a weight of evidence approach.
A.2.2.7.3 Where information from several tiers is inconsistent and/or conflicting with respect to the resulting classification, information of sufficient quality from a higher tier is generally given a higher weight than information from a lower tier. However, when information from a lower tier would result in a stricter classification than information from a higher tier and there is concern for misclassification, then classification is determined by an overall weight of evidence approach. The same would apply in the case where there is human data indicating irritation but positive results from an in vitro/ex vivo test for corrosion.
e.g.,
e.g.,
in vitro/ex vivo
A.2.3 Classification Criteria for Mixtures
A.2.3.1 Classification of Mixtures When Data Are Available for the Complete Mixture
A.2.3.1.1 In general, the mixture shall be classified using the criteria for substances, taking into account the tiered approach to evaluate data for this hazard class (as illustrated in Figure A.2.1) and A.2.3.1.2 and A.2.3.1.3. If classification is not possible using the tiered approach, then the approach described in A.2.3.2, or, if that is not applicable A.2.2.3.3 should be followed.
A.2.3.1.2 In vitro/ex vivo data generated from validated test methods may not have been validated using mixtures; although these methods are considered broadly applicable to mixtures, they can only be used for classification of mixtures when all ingredients of the mixture fall within the applicability domain of the test methods used. Specific limitations regarding applicability domains are described in the respective test methods, and should be taken into consideration as well as any further information on the limitations from the published literature. Where there is reason to assume or evidence indicating that the applicability domain of a particular test method is limited, data interpretation should be exercised with caution, or the results should be considered not applicable.
A.2.3.1.3 In the absence of any other information, a mixture is considered corrosive (Skin Category 1) if it has a pH ≤2 or a pH ≥11.5. However, if consideration of acid/alkaline reserve suggests the mixture may not be corrosive despite the low or high pH value, this needs to be confirmed by other data, preferably from an appropriate validated in vitro/ex vivo test.
A.2.3.2 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.2.3.2.1 Where the mixture itself has not been tested to determine its skin corrosion/irritation potential, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data will be used in accordance with the following bridging principles, as found in paragraph A.0.5 of this Appendix: Dilution, Batching, Concentration of mixtures, Interpolation within one hazard category, Substantially similar mixtures, and Aerosols.
A.2.3.3 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
A.2.3.3.1 In order to make use of all available data for purposes of classifying the skin corrosion/irritation hazards of mixtures, the following assumption has been made and is applied where appropriate in the tiered approach:
The “relevant ingredients” of a mixture are those which are present in concentrations ≥1% (weight/weight for solids, liquids, dusts, mists and vapors and volume/volume for gases.). If the classifier has reason to suspect that an ingredient present at a concentration <1% will affect classification of the mixture for skin corrosion/irritation, that ingredient shall also be considered relevant.
A.2.3.3.2 In general, the approach to classification of mixtures as corrosive or irritant to the skin when data are available on the ingredients, but not on the mixture as a whole, is based on the theory of additivity, such that each corrosive or irritant ingredient contributes to the overall corrosive or irritant properties of the mixture in proportion to its potency and concentration. A weighting factor of 10 is used for corrosive ingredients when they are present at a concentration below the concentration limit for classification with Category 1, but are at a concentration that will contribute to the classification of the mixture as an irritant. The mixture is classified as corrosive or irritant when the sum of the concentrations of such ingredients exceeds a cut-off value/concentration limit.
A.2.3.3.3 Table A.2.3 below provides the cut-off value/concentration limits to be used to determine if the mixture is considered to be corrosive or irritant to the skin.
A.2.3.3.4 Particular care shall be taken when classifying certain types of chemicals such as acids and bases, inorganic salts, aldehydes, phenols, and surfactants. The approach explained in A.2.3.3.1 and A.2.3.3.2 might not work given that many of such substances are corrosive or irritant at concentrations <1%. For mixtures containing strong acids or bases the pH should be used as classification criteria since pH will be a better indicator of corrosion than the concentration limits in Table A.2.3. A mixture containing corrosive or irritant ingredients that cannot be classified based on the additivity approach shown in Table A.2.3, due to chemical characteristics that make this approach unworkable, should be classified as skin corrosion Category 1 if it contains ≥1% of a corrosive ingredient and as skin irritation Category 2 when it contains ≥3% of an irritant ingredient. Classification of mixtures with ingredients for which the approach in Table A.2.3 does not apply is summarized in Table A.2.4 below.
A.2.3.3.5 On occasion, reliable data may show that the skin corrosion/irritation of an ingredient will not be evident when present at a level above the generic cut-off values/concentration limits mentioned in Tables A.2.3 and A.2.4. In these cases the mixture could be classified according to those data ( See Use of cut-off values/concentration limits, paragraph A.0.4.3 of this Appendix ).
A.2.3.3.6 If there are data showing that (an) ingredient(s) may be corrosive or irritant to skin at a concentration of <1% (corrosive) or <3% (irritant), the mixture shall be classified accordingly (See Use of cut-off values/concentration limits, paragraph A.0.4.3 of this Appendix).
| Sum of ingredients classified as: | Concentration triggering classification of a mixture as: | |
|---|---|---|
| Skin corrosive | Skin irritant | |
| Category 1 | Category 2 | |
| Skin Category 1 | ≥5% | ≥1% but <5% |
| Skin Category 2 | ≥10% | |
| (10 × Skin Category 1) + Skin Category 2 | ≥10% | |
| Note: Where data are available and the sub-categories of skin Category 1 (corrosive) are used, the sum of all ingredients of a mixture classified as sub-category 1A, 1B or 1C respectively, must each be ≥5% in order to classify the mixture as either skin sub-category 1A, 1B or 1C. Where the sum of 1A ingredients is <5% but the sum of 1A+1B ingredients is ≥5%, the mixture must be classified as sub-category 1B. Similarly, where the sum of 1A + 1B ingredients is <5% but the sum of 1A + 1B + 1C ingredients is ≥5% the mixture must be classified as sub-category 1C. Where at least one relevant ingredient in a mixture is classified as Category 1 without sub-categorization, the mixture must be classified as Category 1 without sub-categorization if the sum of all ingredients corrosive to skin is ≥5%. |
| Ingredient | Concentration (percent) | Mixture classified as: Skin |
|---|---|---|
| Acid with pH ≤2 | ≥1 | Category 1. |
| Base with pH ≥11.5 | ≥1 | Category 1. |
| Other corrosive (Category 1) ingredient | ≥1 | Category 1. |
| Other irritant (Category 2) ingredient, including acids and bases | ≥ 3 | Category 2. |
A.3 Serious Eye Damage/Eye Irritation
A.3.1 Definitions and General Considerations
A.3.1.1 Serious eye damage refers to the production of tissue damage in the eye, or serious physical decay of vision, which is not fully reversible, occurring after exposure of the eye to a substance or mixture.
Eye irritation refers to the production of changes in the eye, which are fully reversible, occurring after exposure of the eye to a substance or mixture.
A.3.1.2 Serious eye damage/eye irritation shall be classified using a tiered approach as detailed in Figure A.3.1. Emphasis shall be placed upon existing human data ( See A.0.2.6), followed by existing animal data, followed by in vitro data and then other sources of information. Classification results directly when the data satisfy the criteria in this section. In case the criteria cannot be directly applied, classification of a substance or a mixture is made on the basis of the total weight of evidence ( See A.0.3.1). This means that all available information bearing on the determination of serious eye damage/eye irritation is considered together, including the results of appropriate scientifically validated in vitro tests, relevant animal data, and human data such as epidemiological and clinical studies and well-documented case reports and observations.
A.3.2 Classification Criteria for Substances
Substances are allocated to one of the categories within this hazard class, Category 1 (serious eye damage) or Category 2 (eye irritation), as follows:
substances that have the potential to induce reversible eye irritation (see Table A.3.2).
A.3.2.1 Classification Based on Standard Animal Test Data
A.3.2.1.1 Serious eye damage (Category 1)/Irreversible effects on the eye
A single hazard category is provided in Table A.3.1, for substances that have the potential to seriously damage the eyes. Category 1, irreversible effects on the eye, includes the criteria listed below. These observations include animals with grade 4 cornea lesions and other severe reactions (e.g., destruction of cornea) observed at any time during the test, as well as persistent corneal opacity, discoloration of the cornea by a dye substance, adhesion, pannus, and interference with the function of the iris or other effects that impair sight. In this context, persistent lesions are considered those which are not fully reversible within an observation period of normally 21 days. Category 1 also contains substances fulfilling the criteria of corneal opacity ≥ 3 and/or iritis > 1.5 observed in at least 2 of 3 tested animals detected in a Draize eye test with rabbits, because severe lesions like these usually do not reverse within a 21-day observation period.
| Criteria | |
|---|---|
| Category 1: Serious eye damage/Irreversible effects on the eye | A substance that produces: (a) in at least one animal effects on the cornea, iris or conjunctiva that are not expected to reverse or have not fully reversed within an observation period of normally 21 days; and/or |
| (b) in at least 2 of 3 tested animals, a positive response of: | |
| (i) corneal opacity ≥3; and/or | |
| (ii) iritis >1.5; | |
| calculated as the mean scores following grading at 24, 48 and 72 hours after instillation of the test material. | |
| a Grading criteria are understood as described in OECD Test Guideline 405. |
A.3.2.1.2 Eye irritation (category 2)/reversible effects on the eye
A single Category 2 is provided in Table A.3.2 for substances that have the potential to induce reversible eye irritation.
When data are available, substances may be classified into Category 2A and Category 2B:
When a substance is classified as Category 2, without further categorization, the classification criteria are the same as those for 2A.
A.3.2.1.3 For those substances where there is pronounced variability among animal responses this information must be taken into account in determining the classification.
| Criteria | |
|---|---|
| Substances that have the potential to induce reversible eye irritation. | |
| Category 2/2A | Substances that produce in at least 2 of 3 tested animals a positive response of: |
| (a) corneal opacity ≥1; and/or. | |
| (b) iritis ≥1; and/or. | |
| (c) conjunctival redness ≥2; and/or. | |
| (d) conjunctival oedema (chemosis) ≥2. | |
| calculated as the mean scores following grading at 24, 48 and 72 hours after instillation of the test material, and which fully reverses within an observation period of normally 21 days. | |
| Category 2B | Within Category 2A an eye irritant is considered mildly irritating to eyes (Category 2B) when the effects listed above are fully reversible within 7 days of observation. |
| a Grading criteria are understood as described in OECD Test Guideline 405. |
A.3.2.2 Classification in a Tiered Approach
A.3.2.2.1 A tiered approach to the evaluation of initial information shall be used where applicable, recognizing that all elements may not be relevant in certain cases (Figure A.3.1).
A.3.2.2.2 Existing human and animal data should be the first line of analysis, as they give information directly relevant to effects on the eye. Possible skin corrosion shall be evaluated prior to consideration of any testing for serious eye damage/eye irritation in order to avoid testing for local effects on eyes with skin corrosive substances.
A.3.2.2.3 In vitro alternatives that have been validated and accepted should be used to make classification decisions.
A.3.2.2.4 Likewise, pH extremes like ≤2 and ≥11.5, may indicate serious eye damage, especially when associated with significant acid/alkaline reserve (buffering capacity). Generally, such substances are expected to produce significant effects on the eyes. In the absence of any other information, a substance is considered to cause serious eye damage (Category 1) if it has a pH ≤2 or ≥11.5. However, if consideration of acid/alkaline reserve suggests the substance may not cause serious eye damage despite the low or high pH value, this needs to be confirmed by other data, preferably by data from an appropriate validated in vitro test.
A.3.2.2.5 In some cases sufficient information may be available from structurally related substances to make classification decisions.
A.3.2.2.6 The tiered approach provides guidance on how to organize existing information and to make a weight-of-evidence decision about hazard assessment and hazard classification (ideally without conducting new animal tests). Animal testing with corrosive substances should be avoided wherever possible. Although information might be gained from the evaluation of single parameters within a tier, consideration should be given to the totality of existing information and making an overall weight of evidence determination. This is especially true when there is conflict in information available on some parameters.
A.3.2.2.7 The tiered approach explains how to organize existing information and to make a weight-of-evidence decision about hazard assessment and hazard classification. Although information might be gained from the evaluation of single parameters within a tier, consideration should be given to the totality of existing information and making an overall weight of evidence determination. This is especially true when there is conflict in information available.
a Existing human or animal data could be derived from single or repeated exposure(s), for example in occupational, consumer, transport, or emergency response scenarios; or from purposely-generated data from animal studies conducted according to validated and internationally accepted test methods. Although human data from accident or poison center databases can provide evidence for classification, absence of incidents is not itself evidence for no classification as exposures are generally unknown or uncertain;
b Classify in the appropriate category as applicable;
c Existing animal data should be carefully reviewed to determine if sufficient serious eye damage/eye irritation evidence is available through other, similar information. It is recognized that not all skin irritants are eye irritants. Expert judgment should be exercised prior to making such a determination;
d Evidence from studies using validated protocols with isolated human/animal tissues or other non-tissue-based, validated protocols should be assessed. Examples of internationally accepted, validated test methods for identifying eye corrosives and severe irritants (i.e., Serious Eye Damage) include OECD Test Guidelines 437 (Bovine Corneal Opacity and Permeability (BCOP)), 438 (Isolated Chicken Eye (ICE) and 460 (Fluorescein leakage (FL)). Presently there are no validated and internationally accepted in vitro test methods for identifying eye irritation. A positive test result from a validated in vitro test on skin corrosion would lead to the conclusion to classify as causing serious eye damage;
e Measurement of pH alone may be adequate, but assessment of acid/alkaline reserve (buffering capacity) would be preferable. Presently, there is no validated and internationally accepted method for assessing this parameter;
f All information that is available on a substance must be considered and an overall determination made on the total weight of evidence. This is especially true when there is conflict in information available on some parameters. The weight of evidence including information on skin irritation may lead to classification for eye irritation. Negative results from applicable validated in vitro tests are considered in the total weight of evidence evaluation.
A.3.3 Classification Criteria for Mixtures
A.3.3.1 Classification of Mixtures When Data Are Available for the Complete Mixture
A.3.3.1.1 The mixture will be classified using the criteria for substances, and taking into account the tiered approach to evaluate data for this hazard class (as illustrated in Figure A.3.1).
A.3.3.1.2 When considering testing of the mixture, chemical manufacturers shall use a tiered approach as included in the criteria for classification of substances for skin corrosion and serious eye damage and eye irritation to help ensure an accurate classification, as well as to avoid unnecessary animal testing. In the absence of any other information, a mixture is considered to cause serious eye damage (Category 1) if it has a pH ≤2 or ≥11.5. However, if consideration of acid/alkaline reserve suggests the mixture may not have the potential to cause serious eye damage despite the low or high pH value, then further evaluation may be necessary.
A.3.3.2 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.3.3.2.1 Where the mixture itself has not been tested to determine its skin corrosivity or potential to cause serious eye damage or eye irritation, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data will be used in accordance with the following bridging principles, as found in paragraph A.0.5 of this Appendix: Dilution, Batching, Concentration of mixtures, Interpolation within one hazard category, Substantially similar mixtures, and Aerosols.
A.3.3.3 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
A.3.3.3.1 For purposes of classifying the serious eye damage/eye irritation hazards of mixtures in the tiered approach:
The “relevant ingredients” of a mixture are those which are present in concentrations ≥1% (weight/weight for solids, liquids, dusts, mists and vapors and volume/volume for gases.) If the classifier has reason to suspect that an ingredient present at a concentration <1% will affect classification of the mixture for serious eye damage/eye irritation, that ingredient shall also be considered relevant.
A.3.3.3.2 In general, the approach to classification of mixtures as seriously damaging to the eye or eye irritant when data are available on the ingredients, but not on the mixture as a whole, is based on the theory of additivity, such that each skin corrosive or serious eye damage/eye irritant ingredient contributes to the overall serious eye damage/eye irritation properties of the mixture in proportion to its potency and concentration. A weighting factor of 10 is used for skin corrosive and serious eye damaging ingredients when they are present at a concentration below the concentration limit for classification with Category 1, but are at a concentration that will contribute to the classification of the mixture as serious eye damaging/eye irritant. The mixture is classified as seriously damaging to the eye or eye irritant when the sum of the concentrations of such ingredients exceeds a threshold cut-off value/concentration limit.
A.3.3.3.3 Table A.3.3 provides the cut-off value/concentration limits to be used to determine if the mixture must be classified as seriously damaging to the eye or an eye irritant.
A.3.3.3.4 Particular care must be taken when classifying certain types of chemicals such as acids and bases, inorganic salts, aldehydes, phenols, and surfactants. The approach explained in A.3.3.3.1 and A.3.3.3.2 might not work given that many of such substances are seriously damaging to the eye/eye irritating at concentrations <1%. For mixtures containing strong acids or bases, the pH should be used as classification criteria ( See A.3.3.1.2) since pH will be a better indicator of serious eye damage (subject to consideration of acid/alkali reserve) than the concentration limits of Table A.3.3. A mixture containing skin corrosive or serious eye damaging/eye irritating ingredients that cannot be classified based on the additivity approach applied in Table A.3.3 due to chemical characteristics that make this approach unworkable, should be classified as serious eye damage (Category 1) if it contains ≥1% of a skin corrosive or serious eye damaging ingredient and as Eye Irritation (Category 2) when it contains ≥3% of an eye irritant ingredient. Classification of mixtures with ingredients for which the approach in Table A.3.3 does not apply is summarized in Table A.3.4.
A.3.3.3.5 On occasion, reliable data may show that the irreversible/reversible eye effects of an ingredient will not be evident when present at a level above the generic cut-off values/concentration limits mentioned in Tables A.3.3 and A.3.4. In these cases the mixture could be classified according to those data ( See also A.0.4.3 Use of cut-off values/concentration limits ”). On occasion, when it is expected that the skin corrosion/irritation or the reversible/irreversible eye effects of an ingredient will not be evident when present at a level above the generic concentration/cut-off levels mentioned in Tables A.3.3 and A.3.4, testing of the mixture may be considered. In those cases, the tiered weight of evidence approach should be applied as referred to in section A.3.2, Figure A.3.1 and explained in detail in this chapter.
A.3.3.3.6 If there are data showing that (an) ingredient(s) may be corrosive to the skin or seriously damaging to the eye/eye irritating at a concentration of ≤1% (corrosive to the skin or seriously damaging to the eye) or ≤3% (eye irritant), the mixture shall be classified accordingly ( See also paragraph A.0.4.3, Use of cut-off values/concentration limits ).
| Sum of ingredients classified as | Concentration triggering classification of a mixture as | |
|---|---|---|
| Serious eye damage | Eye irritation | |
| Category 1 | Category 2/2A | |
| Skin corrosion (Category 1) + Serious eye damage (Category 1) a | ≥3% | ≥1% but <3% |
| Eye irritation (Category 2) | ≥10% b | |
| 10 × (Skin corrosion (Category 1) + Serious eye damage (Category 1)) a + Eye irritation (Category 2) | ≥10% | |
| Notes: | ||
| a If an ingredient is classified as both skin Category 1 and eye Category 1 its concentration is considered only once in the calculation. | ||
| b A mixture may be classified as Eye Irritation Category 2B in cases when all relevant ingredients are classified as Eye Irritation Category 2B. |
| Ingredient | Concentration (percent) | Mixture classified as |
|---|---|---|
| Acid with pH <2 | ≥1 | Serious eye damage (Category 1). |
| Base with pH ≥11.5 | ≥1 | Serious eye damage (Category 1). |
| Other skin corrosive or serious eye damage (Category 1) ingredients | ≥1 | Serious eye damage (Category 1). |
| Other eye irritant (Category 2) ingredients | ≥3 | Eye irritation (Category 2). |
A.4 Respiratory or Skin Sensitization
A.4.1 Definitions and General Considerations
A.4.1.1 Respiratory sensitization refers to hypersensitivity of the airways occurring after inhalation of a substance or mixture.
Skin sensitization refers to an allergic response occurring after skin contact with a substance or mixture.
A.4.1.2 For the purpose of this chapter, sensitization includes two phases: the first phase is induction of specialized immunological memory in an individual by exposure to an allergen. The second phase is elicitation, i.e., production of a cell-mediated or antibody-mediated allergic response by exposure of a sensitized individual to an allergen.
A.4.1.3 For respiratory sensitization, the pattern of induction followed by elicitation phases is shared in common with skin sensitization. For skin sensitization, an induction phase is required in which the immune system learns to react; clinical symptoms can then arise when subsequent exposure is sufficient to elicit a visible skin reaction (elicitation phase). As a consequence, predictive tests usually follow this pattern in which there is an induction phase, the response to which is measured by a standardized elicitation phase, typically involving a patch test. The local lymph node assay is the exception, directly measuring the induction response. Evidence of skin sensitization in humans normally is assessed by a diagnostic patch test.
A.4.1.4 Usually, for both skin and respiratory sensitization, lower levels are necessary for elicitation than are required for induction.
A.4.1.5 The hazard class “respiratory or skin sensitization” is differentiated into:
A.4.2 Classification Criteria for Substances
A.4.2.1 Respiratory Sensitizers
>A.4.2.1.1 Hazard Categories
A.4.2.1.1.1 Effects seen in either humans or animals will normally justify classification in a weight of evidence approach for respiratory sensitizers. Substances may be allocated to one of the two sub-categories 1A or 1B using a weight of evidence approach in accordance with the criteria given in Table A.4.1 and on the basis of reliable and good quality evidence from human cases or epidemiological studies and/or observations from appropriate studies in experimental animals.
A.4.2.1.1.2 Where data are not sufficient for sub-categorization, respiratory sensitizers shall be classified in Category 1.
| Category 1 | Respiratory sensitizer |
|---|---|
| A substance is classified as a respiratory sensitizer | |
| (a) if there is evidence in humans that the substance can lead to specific respiratory hypersensitivity and/or | |
| (b) if there are positive results from an appropriate animal test. 1 | |
| Sub-category 1A | Substances showing a high frequency of occurrence in humans; or a probability of occurrence of a high sensitization rate in humans based on animal or other tests. 1 Severity of reaction may also be considered. |
| Sub-category 1B | Substances showing a low to moderate frequency of occurrence in humans; or a probability of occurrence of a low to moderate sensitization rate in humans based on animal or other tests. 1 Severity of reaction may also be considered. |
| 1 As of May 20, 2024, recognized and validated animal models for the testing of respiratory hypersensitivity are not available. Under certain circumstances, data from animal studies may provide valuable information in a weight of evidence assessment. |
A.4.2.1.2 Human Evidence
A.4.2.1.2.1 Evidence that a substance can lead to specific respiratory hypersensitivity will normally be based on human experience. In this context, hypersensitivity is normally seen as asthma, but other hypersensitivity reactions such as rhinitis/conjunctivitis and alveolitis are also considered. The condition will have the clinical character of an allergic reaction. However, immunological mechanisms do not have to be demonstrated.
A.4.2.1.2.2 When considering the human evidence, it is necessary that in addition to the evidence from the cases, the following be taken into account:
A.4.2.1.3 The evidence referred to above could be:
A.4.2.1.2.4 Clinical history should include both medical and occupational history to determine a relationship between exposure to a specific substance and development of respiratory hypersensitivity. Relevant information includes aggravating factors both in the home and workplace, the onset and progress of the disease, family history and medical history of the patient in question. The medical history should also include a note of other allergic or airway disorders from childhood and smoking history.
A.4.2.1.2.5 The results of positive bronchial challenge tests are considered to provide sufficient evidence for classification on their own. It is, however, recognized that in practice many of the examinations listed above will already have been carried out.
A.4.2.1.3 Animal studies
A.4.2.1.2.3 Data from appropriate animal studies 2 which may be indicative of the potential of a substance to cause sensitization by inhalation in humans 3 may include:
2 At this writing, recognized and validated animal models for the testing of respiratory hypersensitivity are not available. Under certain circumstances, data from animal studies may provide valuable information in a weight of evidence assessment.
3 The mechanisms by which substances induce symptoms of asthma are not yet fully known. For preventive measures, these substances are considered respiratory sensitizers. However, if on the basis of the evidence, it can be demonstrated that these substances induce symptoms of asthma by irritation only in people with bronchial hyperactivity, they should not be considered as respiratory sensitizers.
A.4.2.2 Skin Sensitizers
A.4.2.2.1 Hazard categories
A.4.2.2.1.1 Effects seen in either humans or animals will normally justify classification in a weight of evidence approach for skin sensitizers. Substances may be allocated to one of the two sub-categories 1A or 1B using a weight of evidence approach in accordance with the criteria given in Table A.4.2 and on the basis of reliable and good quality evidence from human cases or epidemiological studies and/or observations from appropriate studies in experimental animals according to the guidance values provided in A.4.2.2.2.1 and A.4.2.2.3.2 for sub-category 1A and in A.4.2.2.2.2 and A.4.2.2.3.3 for sub-category 1B.
A.4.2.2.1.2 Where data are not sufficient for sub-categorization, skin sensitizers shall be classified in Category 1.
| Category 1 | Skin sensitizer |
|---|---|
| A substance is classified as a skin sensitizer (a) if there is evidence in humans that the substance can lead to sensitization by skin contact in a substantial number of persons, or (b) if there are positive results from an appropriate animal test. | |
| Sub-category 1A | Substances showing a high frequency of occurrence in humans and/or a high potency in animals can be presumed to have the potential to produce significant sensitization in humans. Severity of reaction may also be considered. |
| Sub-category 1B | Substances showing a low to moderate frequency of occurrence in humans and/or a low to moderate potency in animals can be presumed to have the potential to produce sensitization in humans. Severity of reaction may also be considered. |
A.4.2.2.2 Human Evidence
A.4.2.2.2.1 Human evidence for sub-category 1A may include:
A.4.2.2.2.2 Human evidence for sub-category 1B may include:
A.4.2.2.3 Animal Studies
A.4.2.2.3.1 For Category 1, when an adjuvant type test method for skin sensitization is used, a response of at least 30% of the animals is considered as positive. For a non-adjuvant Guinea pig test method, a response of at least 15% of the animals is considered positive. For Category 1, a stimulation index of three or more is considered a positive response in the local lymph node assay. 4
4 Test methods for skin sensitization are described in OECD Guideline 406 (the Guinea Pig Maximization test and the Buehler guinea pig test) and Guideline 429 (Local Lymph Node Assay). Other methods may be used provided that they are scientifically validated. The Mouse Ear Swelling Test (MEST), appears to be a reliable screening test to detect moderate to strong sensitizers, and can be used, in accordance with professional judgment, as a first stage in the assessment of skin sensitization potential.
A.4.2.2.3.2 Animal test results for sub-category 1A can include data with values indicated in the following Table A.4.3:
| Assay | Criteria |
|---|---|
| Local lymph node assay | EC3 value ≤2%. |
| Guinea pig maximization test | ≥30% responding at ≤0.1% intradermal induction dose or ≥60% responding at >0.1% to ≤1% intradermal induction dose. |
| Buehler assay | ≥15% responding at ≤0.2% topical induction dose or ≥60% responding at >0.2% to ≤20% topical induction dose. |
| Note: EC3 refers to the estimated concentration of test chemical required to induce a stimulation index of 3 in the local lymph node assay. |
A.4.2.2.3.3 Animal test results for sub-category 1B can include data with values indicated in Table A.4.4 below:
| Assay | Criteria |
|---|---|
| Local lymph node assay | EC3 value >2%. |
| Guinea pig maximization test | ≥30% to <60% responding at >0.1% to ≤1% intradermal induction dose or ≥30% responding at >1% intradermal induction dose. |
| Buehler assay | ≥15% to <60% responding at >0.2% to ≤20% topical induction dose or ≥15% responding at >20% topical induction dose. |
| Note: EC3 refers to the estimated concentration of test chemical required to induce a stimulation index of 3 in the local lymph node assay. |
A.4.2.2.4 Specific Considerations
A.4.2.2.4.1 For classification of a substance, evidence shall include one or more of the following using a weight of evidence approach:
A.4.2.2.4.2 Evidence from animal studies is usually much more reliable than evidence from human exposure. However, in cases where evidence is available from both sources, and there is conflict between the results, the quality and reliability of the evidence from both sources must be assessed in order to resolve the question of classification on a case-by-case basis. Normally, human data are not generated in controlled experiments with volunteers for the purpose of hazard classification but rather as part of risk assessment to confirm lack of effects seen in animal tests. Consequently, positive human data on skin sensitization are usually derived from case-control or other, less defined studies. Evaluation of human data must, therefore, be carried out with caution as the frequency of cases reflect, in addition to the inherent properties of the substances, factors such as the exposure situation, bioavailability, individual predisposition and preventive measures taken. Negative human data should not normally be used to negate positive results from animal studies. For both animal and human data, consideration should be given to the impact of vehicle.
A.4.2.2.4.3 If none of the above-mentioned conditions are met, the substance need not be classified as a skin sensitizer. However, a combination of two or more indicators of skin sensitization, as listed below, may alter the decision. This shall be considered on a case-by-case basis.
A.4.2.2.4.4 Immunological contact urticaria
A.4.2.2.4.4.1 Substances meeting the criteria for classification as respiratory sensitizers may, in addition, cause immunological contact urticaria. Consideration shall be given to classifying these substances as skin sensitizers.
A.4.2.2.4.4.2 Substances which cause immunological contact urticaria without meeting the criteria for respiratory sensitizers shall be considered for classification as skin sensitizers.
A.4.2.2.4.4.3 There is no recognized animal model available to identify substances which cause immunological contact urticaria. Therefore, classification will normally be based on human evidence, similar to that for skin sensitization.
A.4.3 Classification Criteria for Mixtures
A.4.3.1 Classification of Mixtures When Data Are Available for the Complete Mixture
When reliable and good quality evidence, as described in the criteria for substances, from human experience or appropriate studies in experimental animals, is available for the mixture, then the mixture shall be classified by weight of evidence evaluation of these data. Care must be exercised in evaluating data on mixtures that the dose used does not render the results inconclusive.
A.4.3.2 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.4.3.2.1 Where the mixture itself has not been tested to determine its sensitizing properties, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data will be used in accordance with the following agreed bridging principles as found in paragraph A.0.5 of this Appendix: Dilution, Batching, Concentration of mixtures, Interpolation within one hazard category/subcategory, Substantially similar mixtures, and Aerosols.
A.4.3.3 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
The mixture shall be classified as a respiratory or skin sensitizer when at least one ingredient has been classified as a respiratory or skin sensitizer and is present at or above the appropriate cut-off value/concentration limit for the specific endpoint as shown in Table A.4.5.
| Ingredient classified as | Cut-off values/concentration limits triggering classification of a mixture as | |
|---|---|---|
| Respiratory sensitizer Category 1 | Skin sensitizer Category 1 | |
| Solid/liquid (%) | Gas (%) | All physical states (%) |
| Respiratory Sensitizer Category 1 | ≥0.1 | ≥0.1 |
| Respiratory Sensitizer Sub-category 1A | ≥0.1 | ≥0.1 |
| Respiratory Sensitizer Sub-category 1B | ≥1.0 | ≥0.2 |
| Skin Sensitizer Category 1 | ≥0.1 | |
| Skin Sensitizer Sub-category 1A | ≥0.1 | |
| Skin Sensitizer Sub-category 1B | ≥1.0 |
A.5 Germ Cell Mutagenicity
A.5.1 Definitions and General Considerations
A.5.1.1 Germ cell mutagenicity refers to heritable gene mutations, including heritable structure and numerical chromosome aberrations in germ cells occurring after exposure to a substance or mixture.
A.5.1.2 A mutation is defined as a permanent change in the amount or structure of the genetic material in a cell. The term mutation applies both to heritable genetic changes that may be manifested at the phenotypic level and to the underlying DNA modifications when known (including, for example, specific base pair changes and chromosomal translocations). The term mutagenic and mutagen will be used for agents giving rise to an increased occurrence of mutations in populations of cells and/or organisms.
A.5.1.3 The more general terms genotoxic and genotoxicity apply to agents or processes which alter the structure, information content, or segregation of DNA, including those which cause DNA damage by interfering with normal replication processes, or which in a non-physiological manner (temporarily) alter its replication. Genotoxicity test results are usually taken as indicators for mutagenic effects.
A.5.1.4 This hazard class is primarily concerned with chemicals that may cause mutations in the germ cells of humans that can be transmitted to the progeny. However, mutagenicity/genotoxicity tests in vitro and in mammalian somatic cells in vivo are also considered in classifying substances and mixtures within this hazard class.
A.5.2 Classification Criteria for Substances
A.5.2.1 The classification system provides for two different categories of germ cell mutagens to accommodate the weight of evidence available. The two-category system is described in the Figure A.5.1.
CATEGORY 1:
Category 1A: Substances known to induce heritable mutations in germ cells of humans
Positive evidence from human epidemiological studies.
Category 1B: Substances which should be regarded as if they induce heritable mutations in the germ cells of humans
CATEGORY 2:
Positive evidence obtained from experiments in mammals and/or in some cases from in vitro experiments, obtained from:
Note: Substances which are positive in in vitro mammalian mutagenicity assays, and which also show structure activity relationship to known germ cell mutagens, should be considered for classification as Category 2 mutagens.
A.5.2.2 Specific considerations for classification of substances as germ cell mutagens:
A.5.2.2.1 To arrive at a classification, test results are considered from experiments determining mutagenic and/or genotoxic effects in germ and/or somatic cells of exposed animals. Mutagenic and/or genotoxic effects determined in in vitro tests shall also be considered.
A.5.2.2.2 The system is hazard based, classifying chemicals on the basis of their intrinsic ability to induce mutations in germ cells. The scheme is, therefore, not meant for the (quantitative) risk assessment of chemical substances.
A.5.2.2.3 Classification for heritable effects in human germ cells is made on the basis of scientifically validated tests. Evaluation of the test results shall be done using expert judgment and all the available evidence shall be weighed for classification.
A.5.2.2.4 The classification of substances shall be based on the total weight of evidence available, using expert judgment. In those instances where a single well-conducted test is used for classification, it shall provide clear and unambiguously positive results. The relevance of the route of exposure used in the study of the substance compared to the route of human exposure should also be taken into account.
A.5.3 Classification Criteria for Mixtures 5
5 It should be noted that the classification criteria for health hazards usually include a tiered scheme in which test data available on the complete mixture are considered as the first tier in the evaluation, followed by the applicable bridging principles, and lastly, cut-off values/concentration limits or additivity. However, this approach is not used for Germ Cell Mutagenicity. These criteria for Germ Cell Mutagenicity consider the cut-off values/concentration limits as the primary tier and allow the classification to be modified only on a case-by-case evaluation based on available test data for the mixture as a whole.
A.5.3.1 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
A.5.3.1.1 Classification of mixtures shall be based on the available test data for the individual ingredients of the mixture using cut-off values/concentration limits for the ingredients classified as germ cell mutagens.
A.5.3.1.2 The mixture will be classified as a mutagen when at least one ingredient has been classified as a Category 1A, Category 1B or Category 2 mutagen and is present at or above the appropriate cut-off value/concentration limit as shown in Table A.5.1 below for Category 1 and 2 respectively.
| Ingredient classified as | Cut-off/concentration limits triggering classification of a mixture as: |
|---|---|
| Category 1 mutagen | Category 2 mutagen |
| Category 1A/B mutagen | ≥0.1% |
| Category 2 mutagen | ≥1.0% |
| Note: The cut-off values/concentration limits in the table above apply to solids and liquids (w/w units) as well as gases (v/v units). |
A.5.3.2 Classification of Mixtures When Data Are Available for the Mixture Itself
The classification may be modified on a case-by-case basis based on the available test data for the mixture as a whole. In such cases, the test results for the mixture as a whole must be shown to be conclusive taking into account dose and other factors such as duration, observations and analysis ( e.g., statistical analysis, test sensitivity) of germ cell mutagenicity test systems.
A.5.3.3 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.5.3.3.1 Where the mixture itself has not been tested to determine its germ cell mutagenicity hazard, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data will be used in accordance with the following bridging principles as found in paragraph A.0.5 of this Appendix: Dilution, Batching, and Substantially similar mixtures.
A.5.4 Examples of Scientifically Validated Test Methods
A.5.4.1 Examples of in vivo heritable germ cell mutagenicity tests are:
A.5.4.2 Examples of in vivo somatic cell mutagenicity tests are:
A.5.4.3 Examples of mutagenicity/genotoxicity tests in germ cells are:
A.5.4.4 Examples of genotoxicity tests in somatic cells are:
A.5.4.5 Examples of in vitro mutagenicity tests are:
A.5.4.6 As new, scientifically validated tests arise, these may also be used in the total weight of evidence to be considered.
A.6 Carcinogenicity
A.6.1 Definitions
Carcinogenicity refers to the induction of cancer or an increase in the incidence of cancer occurring after exposure to a substance or mixture. Substances and mixtures which have induced benign and malignant tumors in well-performed experimental studies on animals are considered also to be presumed or suspected human carcinogens unless there is strong evidence that the mechanism of tumor formation is not relevant for humans.
Classification of a substance or mixture as posing a carcinogenic hazard is based on its inherent properties and does not provide information on the level of the human cancer risk which the use of the substance or mixture may represent.
A.6.2 Classification Criteria for Substances 6
6 See Non-mandatory appendix F of this section, part A for further guidance regarding hazard classification for carcinogenicity. This appendix is consistent with the GHS and is provided as guidance excerpted from the International Agency for Research on Cancer (IARC) “Monographs on the Evaluation of Carcinogenic Risks to Humans” (2006).
A.6.2.1 For the purpose of classification for carcinogenicity, substances are allocated to one of two categories based on strength of evidence and additional weight of evidence considerations. In certain instances, route-specific classification may be warranted.
A.6.2.2 Classification as a carcinogen is made on the basis of evidence from reliable and acceptable methods, and is intended to be used for substances which have an intrinsic property to produce such toxic effects. The evaluations are to be based on all existing data, peer-reviewed published studies and additional data accepted by regulatory agencies.
A.6.2.3 Carcinogen classification is a one-step, criterion-based process that involves two interrelated determinations: evaluations of strength of evidence and consideration of all other relevant information to place substances with human cancer potential into hazard categories.
A.6.2.4 Strength of evidence involves the enumeration of tumors in human and animal studies and determination of their level of statistical significance. Sufficient human evidence demonstrates causality between human exposure and the development of cancer, whereas sufficient evidence in animals shows a causal relationship between the agent and an increased incidence of tumors. Limited evidence in humans is demonstrated by a positive association between exposure and cancer, but a causal relationship cannot be stated. Limited evidence in animals is provided when data suggest a carcinogenic effect, but are less than sufficient. (Guidance on consideration of important factors in the classification of carcinogenicity and a more detailed description of the terms “limited” and “sufficient” have been developed by the International Agency for Research on Cancer (IARC) and are provided in non-mandatory appendix F of this section.)
A.6.2.5 Weight of evidence: Beyond the determination of the strength of evidence for carcinogenicity, a number of other factors should be considered that influence the overall likelihood that an agent may pose a carcinogenic hazard in humans. The full list of factors that influence this determination is very lengthy, but some of the important ones are considered here.
A.6.2.5.1 These factors can be viewed as either increasing or decreasing the level of concern for human carcinogenicity. The relative emphasis accorded to each factor depends upon the amount and coherence of evidence bearing on each. Generally, there is a requirement for more complete information to decrease than to increase the level of concern. Additional considerations should be used in evaluating the tumor findings and the other factors in a case-by-case manner.
A.6.2.5.2 Some important factors which may be taken into consideration, when assessing the overall level of concern are:
Additional factors which may increase or decrease the level of concern include:
Mutagenicity: It is recognized that genetic events are central in the overall process of cancer development. Therefore, evidence of mutagenic activity in vivo may indicate that a substance has a potential for carcinogenic effects.
A.6.2.5.3 A substance that has not been tested for carcinogenicity may in certain instances be classified in Category 1A, Category 1B, or Category 2 based on tumor data from a structural analogue together with substantial support from consideration of other important factors such as formation of common significant metabolites, e.g., for benzidine congener dyes.
A.6.2.5.4 The classification should also take into consideration whether or not the substance is absorbed by a given route(s); or whether there are only local tumors at the site of administration for the tested route(s), and adequate testing by other major route(s) show lack of carcinogenicity.
A.6.2.5.5 It is important that whatever is known of the physico-chemical, toxicokinetic and toxicodynamic properties of the substances, as well as any available relevant information on chemical analogues, i.e., structure activity relationship, is taken into consideration when undertaking classification.
A.6.3 Classification Criteria for Mixtures 7
7 It should be noted that the classification criteria for health hazards usually include a tiered scheme in which test data available on the complete mixture are considered as the first tier i the evaluation, followed by the applicable bridging principles, and lastly, cut-off values/concentration limit or addivity. However, this approach is not used for Carcinogenicity. These criteria for Carcinogenicity consider the cut-off values/concentration limits as the primary tier and allow the classification to be modified only on a case-by-case evaluation based on available test data for the mixture as a whole.
A.6.3.1 The mixture shall be classified as a carcinogen when at least one ingredient has been classified as a Category 1 or Category 2 carcinogen and is present at or above the appropriate cut-off value/concentration limit as shown in Table A.6.1.
| Ingredient classified as | Category 1 carcinogen | Category 2 carcinogen |
|---|---|---|
| Category 1 carcinogen | ≥0.1% | |
| Category 2 carcinogen | ≥0.1% (note 1) | |
| Note: If a Category 2 carcinogen ingredient is present in the mixture at a concentration between 0.1% and 1%, information is required on the SDS for a product. However, a label warning is optional. If a Category 2 carcinogen ingredient is present in the mixture at a concentration of ≥1%, both an SDS and a label is required and the information must be included on each. |
A.6.3.2 Classification of mixtures when data are available for the complete mixture
A mixture may be classified based on the available test data for the mixture as a whole. In such cases, the test results for the mixture as a whole must be shown to be conclusive taking into account dose and other factors such as duration, observations and analysis ( e.g., statistical analysis, test sensitivity) of carcinogenicity test systems.
A.6.3.3 Classification of mixtures when data are not available for the complete mixture: bridging principles
Where the mixture itself has not been tested to determine its carcinogenic hazard, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data will be used in accordance with the following bridging principles as found in paragraph A.0.5 of this Appendix: Dilution; Batching; and Substantially similar mixtures.
A.6.4 Classification of Carcinogenicity 8
8 See Non-mandatory appendix f of this section for further guidance regarding hazard classification for carcinogenicity and how to relate carcinogenicity classification information from IARC and NTP to GHS.
A.6.4.1 Chemical manufacturers, importers and employers evaluating chemicals may treat the following sources as establishing that a substance is a carcinogen or potential carcinogen for hazard communication purposes in lieu of applying the criteria described herein:
A.6.4.1.1 National Toxicology Program (NTP), “Report on Carcinogens” (latest edition);
A.6.4.1.2 International Agency for Research on Cancer (IARC) “Monographs on the Evaluation of Carcinogenic Risks to Humans” (latest editions)
A.6.4.2 Where OSHA has included cancer as a health hazard to be considered by classifiers for a chemical covered by 29 CFR part 1910, subpart Z, chemical manufacturers, importers, and employers shall classify the chemical as a carcinogen.
A.7 Reproductive Toxicity
A.7.1 Definitions and General Considerations
A.7.1.1 Reproductive toxicity refers to adverse effects on sexual function and fertility in adult males and females, as well as developmental toxicity in the offspring, occurring after exposure to a substance or mixture. Some reproductive toxic effects cannot be clearly assigned to either impairment of sexual function and fertility or to developmental toxicity. Nonetheless, substances and mixtures with these effects shall be classified as reproductive toxicants. For classification purposes, the known induction of genetically based inheritable effects in the offspring is addressed in Germ cell mutagenicity ( See A.5).
A.7.1.2 Adverse effects on sexual function and fertility means any effect of chemicals that interferes with reproductive ability or sexual capacity. This includes, but is not limited to, alterations to the female and male reproductive system, adverse effects on onset of puberty, gamete production and transport, reproductive cycle normality, sexual behavior, fertility, parturition, pregnancy outcomes, premature reproductive senescence, or modifications in other functions that are dependent on the integrity of the reproductive systems.
A.7.1.3 Adverse effects on development of the offspring means any effect of chemicals which interferes with normal development of the conceptus either before or after birth, which is induced during pregnancy or results from parental exposure. These effects can be manifested at any point in the life span of the organism. The major manifestations of developmental toxicity include death of the developing organism, structural abnormality, altered growth and functional deficiency.
A.7.1.4 Adverse effects on or via lactation are also included in reproductive toxicity, but for classification purposes, such effects are treated separately ( See A.7.2.1).
A.7.2 Classification Criteria for Substances
A.7.2.1 For the purpose of classification for reproductive toxicity, substances shall be classified in one of two categories in accordance with Figure A.7.1(a). Effects on sexual function and fertility, and on development, shall be considered. In addition, effects on or via lactation shall be classified in a separate hazard category in accordance with Figure A.7.1(b).
A.7.2.2.1 Classification is made on the basis of the criteria, outlined above, an assessment of the total weight of evidence, and the use of expert judgment. Classification as a reproductive toxicant is intended to be used for substances which have an intrinsic, specific property to produce an adverse effect on reproduction and substances should not be so classified if such an effect is produced solely as a non-specific secondary consequence of other toxic effects.
A.7.2.2.2 In the evaluation of toxic effects on the developing offspring, it is important to consider the possible influence of maternal toxicity.
A.7.2.2.3 For human evidence to provide the primary basis for a Category 1A classification there must be reliable evidence of an adverse effect on reproduction in humans. Evidence used for classification shall be from well conducted epidemiological studies, if available, which include the use of appropriate controls, balanced assessment, and due consideration of bias or confounding factors. Less rigorous data from studies in humans may be sufficient for a Category 1A classification if supplemented with adequate data from studies in experimental animals, but classification in Category 1B may also be considered.
A.7.2.3 Weight of Evidence
A.7.2.3.1 Classification as a reproductive toxicant is made on the basis of an assessment of the total weight of evidence using expert judgment. This means that all available information that bears on the determination of reproductive toxicity is considered together. Included is information such as epidemiological studies and case reports in humans and specific reproduction studies along with sub-chronic, chronic and special study results in animals that provide relevant information regarding toxicity to reproductive and related endocrine organs. Evaluation of substances chemically related to the material under study may also be included, particularly when information on the material is scarce. The weight given to the available evidence will be influenced by factors such as the quality of the studies, consistency of results, nature and severity of effects, level of statistical significance for intergroup differences, number of endpoints affected, relevance of route of administration to humans and freedom from bias. Both positive and negative results are considered together in a weight of evidence determination. However, a single, positive study performed according to good scientific principles and with statistically or biologically significant positive results may justify classification ( See also A.7.2.2.3).
A.7.2.3.2 Toxicokinetic studies in animals and humans, site of action and mechanism or mode of action study results may provide relevant information, which could reduce or increase concerns about the hazard to human health. If it is conclusively demonstrated that the clearly identified mechanism or mode of action has no relevance for humans or when the toxicokinetic differences are so marked that it is certain that the hazardous property will not be expressed in humans then a chemical which produces an adverse effect on reproduction in experimental animals should not be classified.
A.7.2.3.3 In some reproductive toxicity studies in experimental animals the only effects recorded may be considered of low or minimal toxicological significance and classification may not necessarily be the outcome. These effects include, for example, small changes in semen parameters or in the incidence of spontaneous defects in the fetus, small changes in the proportions of common fetal variants such as are observed in skeletal examinations, or in fetal weights, or small differences in postnatal developmental assessments.
A.7.2.3.4 Data from animal studies shall provide sufficient evidence of specific reproductive toxicity in the absence of other systemic toxic effects. However, if developmental toxicity occurs together with other toxic effects in the dam (mother), the potential influence of the generalized adverse effects should be assessed to the extent possible. The preferred approach is to consider adverse effects in the embryo/fetus first, and then evaluate maternal toxicity, along with any other factors which are likely to have influenced these effects, as part of the weight of evidence. In general, developmental effects that are observed at maternally toxic doses should not be automatically discounted. Discounting developmental effects that are observed at maternally toxic doses can only be done on a case-by-case basis when a causal relationship is established or refuted.
A.7.2.3.5 If appropriate information is available it is important to try to determine whether developmental toxicity is due to a specific maternally mediated mechanism or to a non-specific secondary mechanism, like maternal stress and the disruption of homeostasis. Generally, the presence of maternal toxicity should not be used to negate findings of embryo/fetal effects, unless it can be clearly demonstrated that the effects are secondary non-specific effects. This is especially the case when the effects in the offspring are significant, e.g., irreversible effects such as structural malformations. In some situations it is reasonable to assume that reproductive toxicity is due to a secondary consequence of maternal toxicity and discount the effects, for example if the chemical is so toxic that dams fail to thrive and there is severe inanition; they are incapable of nursing pups; or they are prostrate or dying.
A.7.2.4 Maternal Toxicity
A.7.2.4.1 Development of the offspring throughout gestation and during the early postnatal stages can be influenced by toxic effects in the mother either through non-specific mechanisms related to stress and the disruption of maternal homeostasis, or by specific maternally-mediated mechanisms. So, in the interpretation of the developmental outcome to decide classification for developmental effects it is important to consider the possible influence of maternal toxicity. This is a complex issue because of uncertainties surrounding the relationship between maternal toxicity and developmental outcome. Expert judgment and a weight of evidence approach, using all available studies, shall be used to determine the degree of influence to be attributed to maternal toxicity when interpreting the criteria for classification for developmental effects. The adverse effects in the embryo/fetus shall be first considered, and then maternal toxicity, along with any other factors which are likely to have influenced these effects, as weight of evidence, to help reach a conclusion about classification.
A.7.2.4.2 Based on pragmatic observation, it is believed that maternal toxicity may, depending on severity, influence development via non-specific secondary mechanisms, producing effects such as depressed fetal weight, retarded ossification, and possibly resorptions and certain malformations in some strains of certain species. However, the limited numbers of studies which have investigated the relationship between developmental effects and general maternal toxicity have failed to demonstrate a consistent, reproducible relationship across species. Developmental effects which occur even in the presence of maternal toxicity are considered to be evidence of developmental toxicity, unless it can be unequivocally demonstrated on a case by case basis that the developmental effects are secondary to maternal toxicity. Moreover, classification shall be considered where there is a significant toxic effect in the offspring, e.g., irreversible effects such as structural malformations, embryo/fetal lethality, or significant post-natal functional deficiencies.
A.7.2.4.3 Classification shall not automatically be discounted for chemicals that produce developmental toxicity only in association with maternal toxicity, even if a specific maternally-mediated mechanism has been demonstrated. In such a case, classification in Category 2 may be considered more appropriate than Category 1. However, when a chemical is so toxic that maternal death or severe inanition results, or the dams (mothers) are prostrate and incapable of nursing the pups, it is reasonable to assume that developmental toxicity is produced solely as a secondary consequence of maternal toxicity and discount the developmental effects. Classification is not necessarily the outcome in the case of minor developmental changes, e.g., a small reduction in fetal/pup body weight or retardation of ossification when seen in association with maternal toxicity.
A.7.2.4.4 Some of the endpoints used to assess maternal toxicity are provided below. Data on these endpoints, if available, shall be evaluated in light of their statistical or biological significance and dose-response relationship.
An increased incidence of mortality among the treated dams over the controls shall be considered evidence of maternal toxicity if the increase occurs in a dose-related manner and can be attributed to the systemic toxicity of the test material. Maternal mortality greater than 10% is considered excessive and the data for that dose level shall not normally be considered to need further evaluation.
Consideration of the maternal body weight change and/or adjusted (corrected) maternal body weight shall be included in the evaluation of maternal toxicity whenever such data are available. The calculation of an adjusted (corrected) mean maternal body weight change, which is the difference between the initial and terminal body weight minus the gravid uterine weight (or alternatively, the sum of the weights of the fetuses), may indicate whether the effect is maternal or intrauterine. In rabbits, the body weight gain may not be a useful indicator of maternal toxicity because of normal fluctuations in body weight during pregnancy.
The observation of a significant decrease in the average food or water consumption in treated dams (mothers) compared to the control group may be useful in evaluating maternal toxicity, particularly when the test material is administered in the diet or drinking water. Changes in food or water consumption must be evaluated in conjunction with maternal body weights when determining if the effects noted are reflective of maternal toxicity or more simply, unpalatability of the test material in feed or water.
Increased incidence and/or severity of post-mortem findings may be indicative of maternal toxicity. This can include gross or microscopic pathological findings or organ weight data, including absolute organ weight, organ-to-body weight ratio, or organ-to-brain weight ratio. When supported by findings of adverse histopathological effects in the affected organ(s), the observation of a significant change in the average weight of suspected target organ(s) of treated dams (mothers), compared to those in the control group, may be considered evidence of maternal toxicity.
A.7.2.5 Animal and Experimental Data
A.7.2.5.1 A number of scientifically validated test methods are available, including methods for developmental toxicity testing ( e.g., OECD Test Guideline 414, ICH Guideline S5A, 1993), methods for peri- and post-natal toxicity testing ( e.g., ICH S5B, 1995), and methods for one or two-generation toxicity testing (e.g., OECD Test Guidelines 415, 416, 443).
A.7.2.5.2 Results obtained from screening tests (e.g., OECD Guidelines 421—Reproduction/Developmental Toxicity Screening Test, and 422—Combined Repeated Dose Toxicity Study with Reproduction/Development Toxicity Screening Test) can also be used to justify classification, although the quality of this evidence is less reliable than that obtained through full studies.
A.7.2.5.3 Adverse effects or changes, seen in short- or long-term repeated dose toxicity studies, which are judged likely to impair reproductive function and which occur in the absence of significant generalized toxicity, may be used as a basis for classification, e.g., histopathological changes in the gonads.
A.7.2.5.4 Evidence from in vitro assays, or non-mammalian tests, and from analogous substances using structure-activity relationship (SAR), can contribute to the procedure for classification. In all cases of this nature, expert judgment must be used to assess the adequacy of the data. Inadequate data shall not be used as a primary support for classification.
A.7.2.5.5 It is preferable that animal studies are conducted using appropriate routes of administration which relate to the potential route of human exposure. However, in practice reproductive toxicity studies are commonly conducted using the oral route, and such studies will normally be suitable for evaluating the hazardous properties of the substance with respect to reproductive toxicity. However, if it can be conclusively demonstrated that the clearly identified mechanism or mode of action has no relevance for humans or when the toxicokinetic differences are so marked that it is certain that the hazardous property will not be expressed in humans then a substance which produces an adverse effect on reproduction in experimental animals should not be classified.
A.7.2.5.6 Studies involving routes of administration such as intravenous or intraperitoneal injection, which may result in exposure of the reproductive organs to unrealistically high levels of the test substance, or elicit local damage to the reproductive organs, e.g., by irritation, must be interpreted with extreme caution and on their own are not normally the basis for classification.
A.7.2.5.7 There is general agreement about the concept of a limit dose, above which the production of an adverse effect may be considered to be outside the criteria which lead to classification. Some test guidelines specify a limit dose, other test guidelines qualify the limit dose with a statement that higher doses may be necessary if anticipated human exposure is sufficiently high that an adequate margin of exposure would not be achieved. Also, due to species differences in toxicokinetics, establishing a specific limit dose may not be adequate for situations where humans are more sensitive than the animal model.
A.7.2.5.8 In principle, adverse effects on reproduction seen only at very high dose levels in animal studies (for example doses that induce prostration, severe inappetence, excessive mortality) do not normally lead to classification, unless other information is available, for example, toxicokinetics information indicating that humans may be more susceptible than animals, to suggest that classification is appropriate.
A.7.2.5.9 However, specification of the actual “limit dose” will depend upon the test method that has been employed to provide the test results.
A.7.3 Classification Criteria for Mixtures 9
9 It should be noted that the classification criteria for health hazards usually include a tiered scheme in which test data available on the complete mixture are considered as the first tier in the evaluation, followed by the applicable bridging principles, and lastly, cut-off values/concentration limits or additivity. However, this approach is not used for Reproductive Toxicity. These criteria for Reproductive Toxicity consider the cut-off values/concentration limits as the primary tier and allow the classification to be modified only on a case-by-case evaluation based on available test data for the mixture as a whole.
A.7.3.1 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
A.7.3.1.1 The mixture shall be classified as a reproductive toxicant when at least one ingredient has been classified as a Category 1 or Category 2 reproductive toxicant and is present at or above the appropriate cut-off value/concentration limit specified in Table A.7.1 for Category 1 and 2, respectively.
A.7.3.1.2 The mixture shall be classified for effects on or via lactation when at least one ingredient has been classified for effects on or via lactation and is present at or above the appropriate cut-off value/concentration limit specified in Table A.7.1 for the additional category for effects on or via lactation.
| Ingredients classified as: | Cut-off values/concentration limits triggering classification of a mixture as: | |
|---|---|---|
| Category 1 reproductive toxicant | Category 2 reproductive toxicant | Additional category for effects on or via lactation |
| Category 1 reproductive toxicant | ≥0.1% | |
| Category 2 reproductive toxicant | ≥0.1% | |
| Additional category for effects on or via lactation | ≥0.1% |
A.7.3.2 Classification of Mixtures When Data Are Available for the Complete Mixture
Available test data for the mixture as a whole may be used for classification on a case-by-case basis. In such cases, the test results for the mixture as a whole must be shown to be conclusive taking into account dose and other factors such as duration, observations and analysis ( e.g., statistical analysis, test sensitivity) of reproduction test systems.
A.7.3.3 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.7.3.1.1 Where the mixture itself has not been tested to determine its reproductive toxicity, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data shall be used in accordance with the following bridging principles as found in paragraph A.0.5 of this Appendix: Dilution, Batching, and Substantially similar mixtures.
A.8 Specific Target Organ Toxicity Single Exposure
A.8.1 Definitions and General Considerations
A.8.1.1 Specific target organ toxicity—single exposure, (STOT-SE) refers to specific, non-lethal toxic effects on target organs occurring after a single exposure to a substance or mixture. All significant health effects that can impair function, both reversible and irreversible, immediate and/or delayed and not specifically addressed in A.1 to A.7 and A.10 of this Appendix are included. Specific target organ toxicity following repeated exposure is classified in accordance with SPECIFIC TARGET ORGAN TOXICITY—REPEATED EXPOSURE (A.9 of this Appendix) and is therefore not included here.
A.8.1.2 Classification identifies the chemical as being a specific target organ toxicant and, as such, it presents a potential for adverse health effects in people who are exposed to it.
A.8.1.3 The adverse health effects produced by a single exposure include consistent and identifiable toxic effects in humans; or, in experimental animals, toxicologically significant changes which have affected the function or morphology of a tissue/organ, or have produced serious changes to the biochemistry or hematology of the organism, and these changes are relevant for human health. Human data is the primary source of evidence for this hazard class.
A.8.1.4 Assessment shall take into consideration not only significant changes in a single organ or biological system but also generalized changes of a less severe nature involving several organs.
A.8.1.5 Specific target organ toxicity can occur by any route that is relevant for humans, i.e., principally oral, dermal or inhalation.
A.8.1.6 The classification criteria for specific target organ toxicity—single exposure are organized as criteria for substances Categories 1 and 2 ( See A.8.2.1), criteria for substances Category 3 ( See A.8.2.2) and criteria for mixtures ( See A.8.3). See also Figure A.8.1.
A.8.2 Classification Criteria for Substances
A.8.2.1 Substances of Category 1 and Category 2
A.8.2.1.1 Substances shall be classified for immediate or delayed effects separately, by the use of expert judgment on the basis of the weight of all evidence available, including the use of recommended guidance values ( See A.8.2.1.9). Substances shall then be classified in Category 1 or 2, depending upon the nature and severity of the effect(s) observed, in accordance with Figure A.8.1.
A.8.2.1.3 Classification is determined by expert judgment, on the basis of the weight of all evidence available including the guidance presented below.
A.8.2.1.4 Weight of evidence of all available data, including human incidents, epidemiology, and studies conducted in experimental animals is used to substantiate specific target organ toxic effects that merit classification.
A.8.2.1.5 The information required to evaluate specific target organ toxicity comes either from single exposure in humans (e.g., exposure at home, in the workplace or environmentally), or from studies conducted in experimental animals. The standard animal studies in rats or mice that provide this information are acute toxicity studies which can include clinical observations and detailed macroscopic and microscopic examination to enable the toxic effects on target tissues/organs to be identified. Results of acute toxicity studies conducted in other species may also provide relevant information.
A.8.2.1.6 In exceptional cases, based on expert judgment, it may be appropriate to place certain substances with human evidence of target organ toxicity in Category 2: (a) when the weight of human evidence is not sufficiently convincing to warrant Category 1 classification, and/or (b) based on the nature and severity of effects. Dose/concentration levels in humans shall not be considered in the classification and any available evidence from animal studies shall be consistent with the Category 2 classification. In other words, if there are also animal data available on the substance that warrant Category 1 classification, the chemical shall be classified as Category 1.
A.8.2.1.7 Effects Considered To Support Classification for Category 1 and 2
A.8.2.1.7.1 Classification is supported by evidence associating single exposure to the substance with a consistent and identifiable toxic effect.
A.8.2.1.7.2 Evidence from human experience/incidents is usually restricted to reports of adverse health consequences, often with uncertainty about exposure conditions, and may not provide the scientific detail that can be obtained from well-conducted studies in experimental animals.
A.8.2.1.7.3 Evidence from appropriate studies in experimental animals can furnish much more detail, in the form of clinical observations, and macroscopic and microscopic pathological examination and this can often reveal hazards that may not be life-threatening but could indicate functional impairment. Consequently, all available evidence, and relevance to human health, must be taken into consideration in the classification process. Relevant toxic effects in humans and/or animals include, but are not limited to:
A.8.2.1.8 Effects Considered Not To Support Classification for Category 1 and 2
Effects may be seen in humans and/or animals that do not justify classification. Such effects include, but are not limited to:
A.8.2.1.9 Guidance Values To Assist With Classification Based on the Results Obtained From Studies Conducted in Experimental Animals for Category 1 and 2
A.8.2.1.9.1 In order to help reach a decision about whether a substance shall be classified or not, and to what degree it shall be classified (Category 1 vs. Category 2), dose/concentration “guidance values” are provided for consideration of the dose/concentration which has been shown to produce significant health effects. The principal argument for proposing such guidance values is that all chemicals are potentially toxic and there has to be a reasonable dose/concentration above which a degree of toxic effect is acknowledged.
A.8.2.1.9.2 Thus, in animal studies, when significant toxic effects are observed that indicate classification, consideration of the dose/concentration at which these effects were seen, in relation to the suggested guidance values, provides useful information to help assess the need to classify (since the toxic effects are a consequence of the hazardous property(ies) and also the dose/concentration).
A.8.2.1.9.3 The guidance value (C) ranges for single-dose exposure which has produced a significant non-lethal toxic effect are those applicable to acute toxicity testing, as indicated in Table A.8.1.
| Route of exposure | Units | Guidance value ranges for: | ||
|---|---|---|---|---|
| Category 1 | Category 2 | Category 3 | ||
| Oral (rat) | mg/kg body weight | C ≤ 300 | 2,000 ≥ C > 300 | Guidance values do not apply. |
| Dermal (rat or rabbit) | mg/kg body weight | C ≤ 1,000 | 2,000 ≥ C > 1,000 | |
| Inhalation (rat) gas | ppmV/4h | C ≤ 2,500 | 20,000 ≥ C > 2,500 | |
| Inhalation (rat) vapor | mg/1/4h | C ≤ 10 | 20 ≥ C > 10 | |
| Inhalation (rat) dust/mist/fume | mg/l/4h | C ≤ 1.0 | 5.0 ≥ C > 1.0 |
A.8.2.1.9.4 The guidance values and ranges mentioned in Table A.8.1 are intended only for guidance purposes, i.e., to be used as part of the weight of evidence approach, and to assist with decisions about classification. They are not intended as strict demarcation values. Guidance values are not provided for Category 3 since this classification is primarily based on human data; animal data may be included in the weight of evidence evaluation.
A.8.2.1.9.5 Thus, it is feasible that a specific profile of toxicity occurs at a dose/concentration below the guidance value, e.g., <2,000 mg/kg body weight by the oral route, however the nature of the effect may result in the decision not to classify. Conversely, a specific profile of toxicity may be seen in animal studies occurring at above a guidance value, e.g., ≥2,000 mg/kg body weight by the oral route, and in addition there is supplementary information from other sources, e.g., other single dose studies, or human case experience, which supports a conclusion that, in view of the weight of evidence, classification is the prudent action to take.
A.8.2.1.10 Other Considerations
A.8.2.1.10.1 When a substance is characterized only by use of animal data the classification process includes reference to dose/concentration guidance values as one of the elements that contribute to the weight of evidence approach.
A.8.2.1.10.2 When well-substantiated human data are available showing a specific target organ toxic effect that can be reliably attributed to single exposure to a substance, the substance shall be classified. Positive human data, regardless of probable dose, predominates over animal data. Thus, if a substance is unclassified because specific target organ toxicity observed was considered not relevant or significant to humans, if subsequent human incident data become available showing a specific target organ toxic effect, the substance shall be classified.
A.8.2.1.10.3 A substance that has not been tested for specific target organ toxicity shall, where appropriate, be classified on the basis of data from a scientifically validated structure activity relationship and expert judgment-based extrapolation from a structural analogue that has previously been classified together with substantial support from consideration of other important factors such as formation of common significant metabolites.
A.8.2.2 Substances of Category 3
A.8.2.2.1 Criteria for respiratory tract irritation
The criteria for classifying substances as Category 3 for respiratory tract irritation are:
A.8.2.2.2 Criteria for Narcotic Effects
The criteria for classifying substances in Category 3 for narcotic effects are:
A.8.3 Classification Criteria for Mixtures
A.8.3.1 Mixtures are classified using the same criteria as for substances, or alternatively as described below. As with substances, mixtures may be classified for specific target organ toxicity following single exposure, repeated exposure, or both.
A.8.3.2 Classification of Mixtures When Data Are Available for the Complete Mixture
When reliable and good quality evidence from human experience or appropriate studies in experimental animals, as described in the criteria for substances, is available for the mixture, then the mixture shall be classified by weight of evidence evaluation of this data. Care shall be exercised in evaluating data on mixtures, that the dose, duration, observation or analysis, do not render the results inconclusive.
A.8.3.3 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.8.3.3.1 Where the mixture itself has not been tested to determine its specific target organ toxicity, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data shall be used in accordance with the following bridging principles as found in paragraph A.0.5 of this Appendix: Dilution, Batching, Concentration of mixtures, Interpolation within one hazard category, Substantially similar mixtures, or Aerosols.
A.8.3.4 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
A.8.3.4.1 Where there is no reliable evidence or test data for the specific mixture itself, and the bridging principles cannot be used to enable classification, then classification of the mixture is based on the classification of the ingredient substances. In this case, the mixture shall be classified as a specific target organ toxicant (specific organ specified), following single exposure, repeated exposure, or both when at least one ingredient has been classified as a Category 1 or Category 2 specific target organ toxicant and is present at or above the appropriate cut-off value/concentration limit specified in Table A.8.2 for Categories 1 and 2, respectively.
| Ingredient classified as | Cut-off values/concentration limits triggering classification of a mixture as |
|---|---|
| Category 1 | Category 2 |
| Category 1 Target organ toxicant | ≥1.0% |
| Category 2 Target organ toxicant | ≥1.0% |
A.8.3.4.2 These cut-off values and consequent classifications shall be applied equally and appropriately to both single- and repeated-dose target organ toxicants.
A.8.3.4.3 Mixtures shall be classified for either or both single and repeated dose toxicity independently.
A.8.3.4.4 Care shall be exercised when toxicants affecting more than one organ system are combined that the potentiation or synergistic interactions are considered, because certain substances can cause target organ toxicity at <1% concentration when other ingredients in the mixture are known to potentiate its toxic effect.
A.8.3.4.5 Care shall be exercised when extrapolating the toxicity of a mixture that contains Category 3 ingredient(s). A cut-off value/concentration limit of 20%, considered as an additive of all Category 3 ingredients for each hazard endpoint, is appropriate; however, this cut-off value/concentration limit may be higher or lower depending on the Category 3 ingredient(s) involved and the fact that some effects such as respiratory tract irritation may not occur below a certain concentration while other effects such as narcotic effects may occur below this 20% value. Expert judgment shall be exercised. Respiratory tract irritation and narcotic effects are to be evaluated separately in accordance with the criteria given in A.8.2.2. When conducting classifications for these hazards, the contribution of each ingredient should be considered additive, unless there is evidence that the effects are not additive.
A.8.3.4.6 In cases where the additivity approach is used for Category 3 ingredients, the “relevant ingredients” of a mixture are those which are present in concentrations ≥1% (w/w for solids, liquids, dusts, mists, and vapours and v/v for gases), unless there is a reason to suspect that an ingredient present at a concentration <1% is still relevant when classifying the mixture for respiratory tract irritation or narcotic effects.
A.9 Specific Target Organ Toxicity—Repeated or Prolonged Exposure
A.9.1 Definitions and General Considerations
A.9.1.1 Specific target organ toxicity—repeated exposure (STOT-RE) refers to specific toxic effects on target organs occurring after repeated exposure to a substance or mixture. All significant health effects that can impair function, both reversible and irreversible, immediate and/or delayed and not specifically addressed in A.1 to A.7 and A.10 of this Appendix are included. Specific target organ toxicity following a single-event exposure is classified in accordance with SPECIFIC TARGET ORGAN TOXICITY—SINGLE EXPOSURE (A.8 of this Appendix) and is therefore not included here.
A.9.1.2 Classification identifies the substance or mixture as being a specific target organ toxicant and, as such, it may present a potential for adverse health effects in people who are exposed to it.
A.9.1.3 These adverse health effects produced by repeated exposure include consistent and identifiable toxic effects in humans, or, in experimental animals, toxicologically significant changes which have affected the function or morphology of a tissue/organ, or have produced serious changes to the biochemistry or hematology of the organism and these changes are relevant for human health. Human data will be the primary source of evidence for this hazard class.
A.9.1.4 Assessment shall take into consideration not only significant changes in a single organ or biological system but also generalized changes of a less severe nature involving several organs.
A.9.1.5 Specific target organ toxicity can occur by any route that is relevant for humans, e.g., principally oral, dermal or inhalation.
A.9.2 Classification Criteria for Substances
A.9.2.1 Substances shall be classified as STOT—RE by expert judgment on the basis of the weight of all evidence available, including the use of recommended guidance values which take into account the duration of exposure and the dose/concentration which produced the effect(s), ( See A.9.2.9). Substances shall be placed in one of two categories, depending upon the nature and severity of the effect(s) observed, in accordance with Figure A.9.1.
CATEGORY 1:
Substances are classified in Category 1 for specific target organ toxicity (repeated exposure) on the basis of:
See
CATEGORY 2:
See
See
A.9.2.2 The relevant route of exposure by which the classified substance produces damage shall be identified.
A.9.2.3 Classification is determined by expert judgment, on the basis of the weight of all evidence available including the guidance presented below.
A.9.2.4 Weight of evidence of all data, including human incidents, epidemiology, and studies conducted in experimental animals, is used to substantiate specific target organ toxic effects that merit classification.
A.9.2.5 The information required to evaluate specific target organ toxicity comes either from repeated exposure in humans, e.g., exposure at home, in the workplace or environmentally, or from studies conducted in experimental animals. The standard animal studies in rats or mice that provide this information are 28 day, 90 day or lifetime studies (up to 2 years) that include hematological, clinico-chemical and detailed macroscopic and microscopic examination to enable the toxic effects on target tissues/organs to be identified. Data from repeat dose studies performed in other species may also be used. Other long-term exposure studies, e.g., for carcinogenicity, neurotoxicity or reproductive toxicity, may also provide evidence of specific target organ toxicity that could be used in the assessment of classification.
A.9.2.6 In exceptional cases, based on expert judgment, it may be appropriate to place certain substances with human evidence of specific target organ toxicity in Category 2: (a) when the weight of human evidence is not sufficiently convincing to warrant Category 1 classification, and/or (b) based on the nature and severity of effects. Dose/concentration levels in humans shall not be considered in the classification and any available evidence from animal studies shall be consistent with the Category 2 classification. In other words, if there are also animal data available on the substance that warrant Category 1 classification, the substance shall be classified as Category 1.
A.9.2.7 Effects Considered To Support Classification
A.9.2.7.1 Classification is supported by reliable evidence associating repeated exposure to the substance with a consistent and identifiable toxic effect.
A.9.2.7.2 Evidence from human experience/incidents is usually restricted to reports of adverse health consequences, often with uncertainty about exposure conditions, and may not provide the scientific detail that can be obtained from well-conducted studies in experimental animals.
A.9.2.7.3 Evidence from appropriate studies in experimental animals can furnish much more detail, in the form of clinical observations, hematology, clinical chemistry, macroscopic and microscopic pathological examination and this can often reveal hazards that may not be life-threatening but could indicate functional impairment. Consequently, all available evidence, and relevance to human health, must be taken into consideration in the classification process. Relevant toxic effects in humans and/or animals include, but are not limited to:
A.9.2.8 Effects Considered Not To Support Classification
Effects may be seen in humans and/or animals that do not justify classification. Such effects include, but are not limited to:
A.9.2.9 Guidance Values To Assist With Classification Based on the Results Obtained From Studies Conducted in Experimental Animals
A.9.2.9.1 In studies conducted in experimental animals, reliance on observation of effects alone, without reference to the duration of experimental exposure and dose/concentration, omits a fundamental concept of toxicology, i.e., all substances are potentially toxic, and what determines the toxicity is a function of the dose/concentration and the duration of exposure. In most studies conducted in experimental animals the test guidelines use an upper limit dose value.
A.9.2.9.2 In order to help reach a decision about whether a substance shall be classified or not, and to what degree it shall be classified (Category 1 vs. Category 2), dose/concentration “guidance values” are provided in Table A.9.1 for consideration of the dose/concentration which has been shown to produce significant health effects. The principal argument for proposing such guidance values is that all chemicals are potentially toxic and there has to be a reasonable dose/concentration above which a degree of toxic effect is acknowledged. Also, repeated-dose studies conducted in experimental animals are designed to produce toxicity at the highest dose used in order to optimize the test objective and so most studies will reveal some toxic effect at least at this highest dose. What is therefore to be decided is not only what effects have been produced, but also at what dose/concentration they were produced and how relevant is that for humans.
A.9.2.9.3 Thus, in animal studies, when significant toxic effects are observed that indicate classification, consideration of the duration of experimental exposure and the dose/concentration at which these effects were seen, in relation to the suggested guidance values, provides useful information to help assess the need to classify (since the toxic effects are a consequence of the hazardous property(ies) and also the duration of exposure and the dose/concentration).
A.9.2.9.4 The decision to classify at all can be influenced by reference to the dose/concentration guidance values at or below which a significant toxic effect has been observed.
A.9.2.9.5 The guidance values refer to effects seen in a standard 90-day toxicity study conducted in rats. They can be used as a basis to extrapolate equivalent guidance values for toxicity studies of greater or lesser duration, using dose/exposure time extrapolation similar to Haber's rule for inhalation, which states essentially that the effective dose is directly proportional to the exposure concentration and the duration of exposure. The assessment should be done on a case- by-case basis; for example, for a 28-day study the guidance values below would be increased by a factor of three.
A.9.2.9.6 Thus for Category 1 classification, significant toxic effects observed in a 90-day repeated-dose study conducted in experimental animals and seen to occur at or below the (suggested) guidance values (C) as indicated in Table A.9.1 would justify classification:
| Route of exposure | Units | Guidance values (dose/concentration) |
|---|---|---|
| Oral (rat) | mg/kg body weight/day | C ≤ 10 |
| Dermal (rat or rabbit) | mg/kg body weight/day | C ≤ 20 |
| Inhalation (rat) gas | ppmV/6h/day | C ≤ 50 |
| Inhalation (rat) vapor | mg/liter/6h/day | C ≤ 0.2 |
| Inhalation (rat) dust/mist/fume | mg/liter/6h/day | C ≤ 0.02 |
A.9.2.9.7 For Category 2 classification, significant toxic effects observed in a 90-day repeated-dose study conducted in experimental animals and seen to occur within the (suggested) guidance value ranges as indicated in Table A.9.2 would justify classification:
| Route of exposure | Units | Guidance value range (dose/concentration) |
|---|---|---|
| Oral (rat) | mg/kg body weight/day | 10 < C ≤ 100 |
| Dermal (rat or rabbit) | mg/kg body weight/day | 20 < C ≤ 200 |
| Inhalation (rat) gas | ppmV/6h/day | 50 < C ≤ 250 |
| Inhalation (rat) vapor | mg/liter/6h/day | 0.2 < C ≤ 1.0 |
| Inhalation (rat) dust/mist/fume | mg/liter/6h/day | 0.02 < C ≤ 0.2 |
A.9.2.9.8 The guidance values and ranges mentioned in A.2.9.9.6 and A.2.9.9.7 are intended only for guidance purposes, i.e., to be used as part of the weight of evidence approach, and to assist with decisions about classification. They are not intended as strict demarcation values.
A.9.2.9.9 Thus, it is possible that a specific profile of toxicity occurs in repeat-dose animal studies at a dose/concentration below the guidance value, e.g., <100 mg/kg body weight/day by the oral route, however the nature of the effect, e.g., nephrotoxicity seen only in male rats of a particular strain known to be susceptible to this effect, may result in the decision not to classify. Conversely, a specific profile of toxicity may be seen in animal studies occurring at above a guidance value, e.g., ≥100 mg/kg body weight/day by the oral route, and in addition there is supplementary information from other sources, e.g., other long-term administration studies, or human case experience, which supports a conclusion that, in view of the weight of evidence, classification is prudent.
A.9.2.10 Other Considerations
A.9.2.10.1 When a substance is characterized only by use of animal data the classification process includes reference to dose/concentration guidance values as one of the elements that contribute to the weight of evidence approach.
A.9.2.10.2 When well-substantiated human data are available showing a specific target organ toxic effect that can be reliably attributed to repeated or prolonged exposure to a substance, the substance shall be classified. Positive human data, regardless of probable dose, predominates over animal data. Thus, if a substance is unclassified because no specific target organ toxicity was seen at or below the dose/concentration guidance value for animal testing, if subsequent human incident data become available showing a specific target organ toxic effect, the substance shall be classified.
A.9.2.10.3 A substance that has not been tested for specific target organ toxicity may in certain instances, where appropriate, be classified on the basis of data from a scientifically validated structure activity relationship and expert judgment-based extrapolation from a structural analogue that has previously been classified together with substantial support from consideration of other important factors such as formation of common significant metabolites.
A.9.3 Classification Criteria for Mixtures
A.9.3.1 Mixtures are classified using the same criteria as for substances, or alternatively as described below. As with substances, mixtures may be classified for specific target organ toxicity following single exposure, repeated exposure, or both.
A.9.3.2 Classification of Mixtures When Data Are Available for the Complete Mixture
When reliable and good quality evidence from human experience or appropriate studies in experimental animals, as described in the criteria for substances, is available for the mixture, then the mixture shall be classified by weight of evidence evaluation of these data. Care shall be exercised in evaluating data on mixtures, that the dose, duration, observation or analysis, do not render the results inconclusive.
A.9.3.3 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.9.3.3.1 Where the mixture itself has not been tested to determine its specific target organ toxicity, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazards of the mixture, these data shall be used in accordance with the following bridging principles as found in paragraph A.0.5 of this Appendix: Dilution; Batching; Concentration of mixtures; Interpolation within one hazard category; Substantially similar mixtures; and Aerosols.
A.9.3.4 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
A.9.3.4.1 Where there is no reliable evidence or test data for the specific mixture itself, and the bridging principles cannot be used to enable classification, then classification of the mixture is based on the classification of the ingredient substances. In this case, the mixture shall be classified as a specific target organ toxicant (specific organ specified), following single exposure, repeated exposure, or both when at least one ingredient has been classified as a Category 1 or Category 2 specific target organ toxicant and is present at or above the appropriate cut-off value/concentration limit specified in Table A.9.3 for Category 1 and 2 respectively.
| Ingredient classified as | Cut-off values/concentration limits triggering classification of a mixture as |
|---|---|
| Category 1 | Category 2 |
| Category 1 Target organ toxicant | ≥1.0% |
| Category 2 Target organ toxicant | ≥1.0% |
A.9.3.4.2 These cut-off values and consequent classifications shall be applied equally and appropriately to both single- and repeated-dose target organ toxicants.
A.9.3.4.3 Mixtures shall be classified for either or both single- and repeated-dose toxicity independently.
A.9.3.4.4 Care shall be exercised when toxicants affecting more than one organ system are combined that the potentiation or synergistic interactions are considered, because certain substances can cause specific target organ toxicity at <1% concentration when other ingredients in the mixture are known to potentiate its toxic effect.
A.10 Aspiration Hazard
A.10.1 Definitions and General Considerations
A.10.1.1 Aspiration hazard refers to severe acute effects such as chemical pneumonia, pulmonary injury or death occurring after aspiration of a substance or mixture.
A.10.1.2 Aspiration means the entry of a liquid or solid chemical directly through the oral or nasal cavity, or indirectly from vomiting, into the trachea and lower respiratory system.
A.10.1.3 Aspiration is initiated at the moment of inspiration, in the time required to take one breath, as the causative material lodges at the crossroad of the upper respiratory and digestive tracts in the laryngopharyngeal region.
A.10.1.4 Aspiration of a substance or mixture can occur as it is vomited following ingestion. This may have consequences for labeling, particularly where, due to acute toxicity, a recommendation may be considered to induce vomiting after ingestion. However, if the substance/mixture also presents an aspiration toxicity hazard, the recommendation to induce vomiting may need to be modified.
A.10.1.5 Specific Considerations
A.10.1.5.1 The classification criteria refer to kinematic viscosity. The following provides the conversion between dynamic and kinematic viscosity:
A.10.1.5.2 Although the definition of aspiration in A.10.1.1 includes the entry of solids into the respiratory system, classification according to (b) in table A.10.1 for Category 1 is intended to apply to liquid substances and mixtures only.
A.10.1.5.3 Classification of aerosol/mist products
Aerosol and mist products are usually dispensed in containers such as self- pressurized containers, trigger and pump sprayers. Classification for these products shall be considered if their use may form a pool of product in the mouth, which then may be aspirated. If the mist or aerosol from a pressurized container is fine, a pool may not be formed. On the other hand, if a pressurized container dispenses product in a stream, a pool may be formed that may then be aspirated. Usually, the mist produced by trigger and pump sprayers is coarse and therefore, a pool may be formed that then may be aspirated. When the pump mechanism may be removed and contents are available to be swallowed then the classification of the products should be considered.
A.10.2 Classification Criteria for Substances
A.10.3.1 Classification When Data Are Available for the Complete Mixture
A mixture shall be classified in Category 1 based on reliable and good quality human evidence.
A.10.3.2 Classification of Mixtures When Data Are Not Available for the Complete Mixture: Bridging Principles
A.10.3.2.1 Where the mixture itself has not been tested to determine its aspiration toxicity, but there are sufficient data on both the individual ingredients and similar tested mixtures to adequately characterize the hazard of the mixture, these data shall be used in accordance with the following bridging principles as found in paragraph A.0.5 of this Appendix: Dilution; Batching; Concentration of mixtures; Interpolation within one hazard category; and Substantially similar mixtures. For application of the dilution bridging principle, the concentration of aspiration toxicants shall not be less than 10%.
A.10.3.3 Classification of Mixtures When Data Are Available for All Ingredients or Only for Some Ingredients of the Mixture
A.10.3.3.1 The “relevant ingredients” of a mixture are those which are present in concentrations ≥1%.
A.10.3.3.2 Category 1
A.10.3.3.2.1 A mixture is classified as Category 1 when the sum of the concentrations of Category 1 ingredients is ≥10%, and the mixture has a kinematic viscosity of ≤20.5 mm 2 /s, measured at 40 °C.
A.10.3.3.2.2 In the case of a mixture which separates into two or more distinct layers, the entire mixture is classified as Category 1 if in any distinct layer the sum of the concentrations of Category 1 ingredients is ≥10%, and it has a kinematic viscosity of ≤20.5 mm 2 /s, measured at 40 °C.
Appendix B to § 1910.1200—Physical Hazard Criteria (Mandatory)
B.1 Explosives
B.1.1 Definitions and General Considerations
B.1.1.1 An explosive chemical is a solid or liquid chemical which is in itself capable by chemical reaction of producing gas at such a temperature and pressure and at such a speed as to cause damage to the surroundings. Pyrotechnic chemicals are included even when they do not evolve gases.
A pyrotechnic chemical is a chemical designed to produce an effect by heat, light, sound, gas or smoke or a combination of these as the result of non-detonative self-sustaining exothermic chemical reactions.
An explosive item is an item containing one or more explosive chemicals.
A pyrotechnic item is an item containing one or more pyrotechnic chemicals.
An unstable explosive is an explosive which is thermally unstable and/or too sensitive for normal handling, transport, or use.
An intentional explosive is a chemical or item which is manufactured with a view to produce a practical explosive or pyrotechnic effect.
B.1.1.2 The class of explosives comprises:
B.1.2 Classification Criteria
Chemicals and items of this class shall be classified as unstable explosives or shall be assigned to one of the following six divisions depending on the type of hazard they present:
B.1.3 Additional Classification Considerations
B.1.3.1 Explosives shall be classified as unstable explosives or shall be assigned to one of the six divisions identified in B.1.2 in accordance with the three step procedure in Part I of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6). The first step is to ascertain whether the substance or mixture has explosive effects (Test Series 1). The second step is the acceptance procedure (Test Series 2 to 4) and the third step is the assignment to a hazard division (Test Series 5 to 7). The assessment whether a candidate for “ammonium nitrate emulsion or suspension or gel, intermediate for blasting explosives (ANE)” is insensitive enough for inclusion as an oxidizing liquid ( see B.13 of this appendix) or an oxidizing solid ( see B.14 of this appendix) is determined by Test Series 8 tests of UN ST/SG/AC.10/.
B.1.3.2 Explosive properties are associated with the presence of certain chemical groups in a molecule which can react to produce very rapid increases in temperature or pressure. The screening procedure in B.1.3.1 is aimed at identifying the presence of such reactive groups and the potential for rapid energy release. If the screening procedure identifies the chemical as a potential explosive, the acceptance procedure ( see section 10.3 of the UN ST/SG/AC.10 (incorporated by reference; see § 1910.6)) is necessary for classification.
B.1.3.3 If a mixture contains any known explosives, the acceptance procedure is necessary for classification.
B.1.3.4 A chemical is not classified as explosive if:
The oxygen balance is calculated for the chemical reaction:
2
2
using the formula: oxygen balance = −1600 [2x + (y/2)−z]/molecular weight; or
B.2 Flammable Gases
B.2.1 Definition
Flammable gas means a gas having a flammable range with air at 20 °C (68 °F) and a standard pressure of 101.3 kPa (14.7 psi).
A pyrophoric gas means a flammable gas that is liable to ignite spontaneously in air at a temperature of 54 °C (130 °F) or below.
A chemically unstable gas means a flammable gas that is able to react explosively even in the absence of air or oxygen.
B.2.2 Classification Criteria
B.2.2.1 A flammable gas shall be classified in Category 1A, 1B, or 2 in accordance with Table B.2.1:
B.2.3.1 Flammability shall be determined by tests or by calculation in accordance with ISO 10156:1996 or ISO 10156:2017 (incorporated by reference; see § 1910.6) and, if using fundamental burning velocity for Category 1B, use Annex C: Method of test for burning velocity measurement of flammable gases of ISO 817:2014(E) (incorporated by reference; see § 1910.6). Where insufficient data are available to use this method, equivalent validated methods may be used.
B.2.3.2 Pyrophoricity shall be determined at 130 °F (54 °C) in accordance with either IEC 60079-20-1 or DIN 51794:2003 (incorporated by reference; see § 1910.6).
B.2.3.3 The classification procedure for pyrophoric gases need not be applied when experience in production or handling shows that the substance does not ignite spontaneously on coming into contact with air at a temperature of 130 °F (54 °C) or below. Flammable gas mixtures, which have not been tested for pyrophoricity and which contain more than one percent pyrophoric components shall be classified as a pyrophoric gas. Expert judgement on the properties and physical hazards of pyrophoric gases and their mixtures should be used in assessing the need for classification of flammable gas mixtures containing one percent or less pyrophoric components. In this case, testing need only be considered if expert judgement indicates a need for additional data to support the classification process.
B.2.3.4 Chemical instability shall be determined in accordance with the method described in Part III of the UN ST/SG/AC.10/11/Rev.6 (incorporated by reference; see § 1910.6). If the calculations performed in accordance with ISO 10156:1996 or ISO 10156:2017 (incorporated by reference; see § 1910.6) show that a gas mixture is not flammable, no additional testing is required for determining chemical instability for classification purposes.
B.3 Aerosols and Chemicals Under Pressure
B.3.1 Aerosols
B.3.1.1 Definition
Aerosol means any non-refillable receptacle containing a gas compressed, liquefied or dissolved under pressure, and fitted with a release device allowing the contents to be ejected as particles in suspension in a gas, or as a foam, paste, powder, liquid or gas.
B.3.1.2 Classification Criteria
B.3.1.2.1 Aerosols are classified in one of three categories, depending on their flammable properties and their heat of combustion. Aerosols shall be considered for classification in Categories 1 or 2 if they contain more than 1% components (by mass) which are classified as flammable in accordance with this Appendix B, i.e.:
Flammable gases ( see B.2);
Flammable liquids ( see B.6)
Flammable solids ( see B.7)
or if their heat of combustion is at least 20 kJ/g.
B.3.1.2.2 An aerosol shall be classified in one of the three categories for this class in accordance with Table B.3.1.
B.3.2.1 Definition
C hemicals under pressure are liquids or solids ( e.g., pastes or powders), pressurized with a gas at a pressure of 200 kPa (gauge) or more at 20 °C in pressure receptacles other than aerosol dispensers and which are not classified as gases under pressure.
B.3.2.2 Classification Criteria
B.3.2.2.1 Chemicals under pressure are classified in one of three categories of this hazard class, in accordance with Table B.3.2, depending on their content of flammable components and their heat of combustion
B.3.2.2.2 Flammable components are components which are classified as flammable in accordance with the GHS criteria, i.e.:
see
see
see
B.3.3.1 To classify an aerosol, data on its flammable components, on its chemical heat of combustion and, if applicable, the results of the aerosol foam flammability test (for foam aerosols) and of the ignition distance test and enclosed space test (for spray aerosols) are necessary.
B.3.3.2 The chemical heat of combustion (ΔHc), in kilojoules per gram (kJ/g), is the product of the theoretical heat of combustion (ΔHcomb), and a combustion efficiency, usually less than 1.0 (a typical combustion efficiency is 0.95 or 95%).
For a composite formulation, the chemical heat of combustion is the summation of the weighted heats of combustion for the individual components, as follows:
where:
c
c
w(i) = mass fraction of component i in the product;
n = total number of components in the product.
B.3.3.3 The chemical heats of combustion shall be found in literature, calculated or determined by tests: (see ASTM D 240-02; Sections 86.1 to 86.3 of ISO 13943; and NFPA 30B (incorporated by reference, see § 1910.6)).
B.3.3.4 The Ignition Distance Test, Enclosed Space Ignition Test and Aerosol Foam Flammability Test shall be performed in accordance with sub-sections 31.4, 31.5 and 31.6 of UN ST/SG/AC.10 (incorporated by reference; see § 1910.6).
B.4 Oxidizing Gases
B.4.1 Definition
Oxidizing gas means any gas which may, generally by providing oxygen, cause or contribute to the combustion of other material more than air does.
B.4.2 Classification Criteria
An oxidizing gas shall be classified in a single category for this class in accordance with Table B.4.1:
| Category | Criteria |
|---|---|
| 1 | Any gas which may, generally by providing oxygen, cause or contribute to the combustion of other material more than air does. |
B.4.3 Additional Classification Considerations
Classification shall be in accordance with tests or calculation methods as described in ISO 10156:1996, ISO 10156:2017 or 10156-2:2005 (incorporated by reference; see § 1910.6).
B.5 Gases Under Pressure
B.5.1 Definition
Gases under pressure are gases which are contained in a receptacle at a pressure of 200 kPa (29 psi) (gauge) or more at 20 °C (68 °F), or which are liquefied or liquefied and refrigerated.
They comprise compressed gases, liquefied gases, dissolved gases and refrigerated liquefied gases.
B.5.2 Classification Criteria
Gases under pressure shall be classified in one of four groups in accordance with Table B.5.1:
Note: Aerosols and chemicals under pressure should not be classified as gases under pressure. See Appendix B.3 of this section.
B.6 Flammable Liquids
B.6.1 Definition
Flammable liquid means a liquid having a flash point of not more than 93 °C (199.4 °F).
Flash point means the minimum temperature at which a liquid gives off vapor in sufficient concentration to form an ignitable mixture with air near the surface of the liquid, as determined by a method identified in Section B.6.3 of this appendix.
B.6.2 Classification Criteria
A flammable liquid shall be classified in one of four categories in accordance with Table B.6.1 of this appendix:
The flash point shall be determined in accordance with ASTM D56-05, ASTM D3278, ASTM D3828, ASTM D93-08 (incorporated by reference, see § 1910.6), or any method specified in 29 CFR 1910.106(a)(14). It may also be determined by any other method specified in GHS Revision 7, Chapter 2.6.
The initial boiling point shall be determined in accordance with ASTM D86-07a or ASTM D1078 (incorporated by reference; see § 1910.6). 1
1 To determine the appropriate flammable liquid storage container size and type, the boiling point shall be determined by § 1910.106(a)(5). In addition, the manufacturer, importer, and distributor shall clearly note in sections 7 and 9 of the SDS if an alternate calculation was used for storage purposes and the classification for storage differs from the classification listed in Section 2 of the SDS.
B.7 Flammable Solids
B.71 Definitions
Flammable solid means a solid which is a readily combustible solid, or which may cause or contribute to fire through friction.
Readily combustible solids are powdered, granular, or pasty chemicals which are dangerous if they can be easily ignited by brief contact with an ignition source, such as a burning match, and if the flame spreads rapidly.
B.7.2 Classification Criteria
B.7.2.1 Powdered, granular or pasty chemicals shall be classified as flammable solids when the time of burning of one or more of the test runs, performed in accordance with the test method described in Part III, sub-section 33.2.1 of UN ST/SG/AC.10 (incorporated by reference; see § 1910.6), is less than 45 s or the rate of burning is more than 2.2 mm/s (0.0866 in/s).
B.7.2.2 Powders of metals or metal alloys shall be classified as flammable solids when they can be ignited and the reaction spreads over the whole length of the sample in 10 min or less.
B.7.2.3 Solids which may cause fire through friction shall be classified in this class by analogy with existing entries ( e.g., matches) until definitive criteria are established.
B.7.2.4 A flammable solid shall be classified in one of the two categories for this class using Method N.1 as described in Part III, sub-section 33.2.1 of UN ST/SG/AC.10 (incorporated by reference; see § 1910.6), in accordance with Table B.7.1:
B.8.1 Definitions
Self-reactive chemicals are thermally unstable liquid or solid chemicals liable to undergo a strongly exothermic decomposition even without participation of oxygen (air). This definition excludes chemicals classified under this section as explosives, organic peroxides, oxidizing liquids or oxidizing solids.
A self-reactive chemical is regarded as possessing explosive properties when in laboratory testing the formulation is liable to detonate, to deflagrate rapidly or to show a violent effect when heated under confinement.
B.8.2 Classification Criteria
B.8.2.1 A self-reactive chemical shall be considered for classification in this class unless:
B.8.2.2 Mixtures of oxidizing substances, meeting the criteria for classification as oxidizing liquids or oxidizing solids, which contain 5% or more of combustible organic substances and which do not meet the criteria mentioned in B.8.2.1(a), (c), (d) or (e), shall be subjected to the self-reactive chemicals classification procedure in B.8.2.3. Such a mixture showing the properties of a self-reactive chemical type B to F shall be classified as a self-reactive chemical.
B.8.2.3 Self-reactive chemicals shall be classified in one of the seven categories of “types A to G” for this class, according to the following principles:
B.8.3 Additional Classification Considerations
B.8.3.1 For purposes of classification, the properties of self-reactive chemicals shall be determined in accordance with test series A to H as described in Part II of UN ST/SG/AC.10 (incorporated by reference; see § 1910.6).
B.8.3.2 Self-accelerating decomposition temperature (SADT) shall be determined in accordance with Part II, section 28 of UN ST/SG/AC.10, (incorporated by reference; see § 1910.6).
B.8.3.3 The classification procedures for self-reactive substances and mixtures need not be applied if:
B.9 Pyrophoric Liquids
B.9.1 Definition
Pyrophoric liquid means a liquid which, even in small quantities, is liable to ignite within five minutes after coming into contact with air.
B.9.2 Classification Criteria
A pyrophoric liquid shall be classified in a single category for this class using test N.3 in Part III, sub-section 33.3.1.5 of UN ST/SG/AC.10 (incorporated by reference; see § 1910.6), in accordance with Table B.9.1 of this appendix:
| Category | Criteria |
|---|---|
| 1 | The liquid ignites within 5 min when added to an inert carrier and exposed to air, or it ignites or chars a filter paper on contact with air within 5 min. |
B.9.3 Additional Classification Considerations
The classification procedure for pyrophoric liquids need not be applied when experience in production or handling shows that the chemical does not ignite spontaneously on coming into contact with air at normal temperatures ( i.e., the substance is known to be stable at room temperature for prolonged periods of time (days)).
B.10 Pyrophoric Solids
B.10.1 Definition
Pyrophoric solid means a solid which, even in small quantities, is liable to ignite within five minutes after coming into contact with air.
B.10.2 Classification Criteria
A pyrophoric solid shall be classified in a single category for this class using test N.2 in Part III, sub-section 33.3.1.4 of UN ST/SG/AC.10 (incorporated by reference; see § 1910.6), in accordance with Table B.10.1 of this appendix:
| Category | Criteria |
|---|---|
| 1 | The solid ignites within 5 min of coming into contact with air. |
B.10.3 Additional Classification Considerations
The classification procedure for pyrophoric solids need not be applied when experience in production or handling shows that the chemical does not ignite spontaneously on coming into contact with air at normal temperatures ( i.e., the chemical is known to be stable at room temperature for prolonged periods of time (days)).
B.11—Self-Heating Chemicals
B.11.1 Definition
A self-heating chemical is a solid or liquid chemical, other than a pyrophoric liquid or solid, which, by reaction with air and without energy supply, is liable to self-heat; this chemical differs from a pyrophoric liquid or solid in that it will ignite only when in large amounts (kilograms) and after long periods of time (hours or days).
B.11.2 Classification Criteria
B.11.2.1 A self-heating chemical shall be classified in one of the two categories for this class if, in tests performed in accordance with test method N.4 in Part III, sub-section 33.3.1.6 of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6), the result meets the criteria shown in Table B.11.1.
| Category | Criteria |
|---|---|
| 1 | A positive result is obtained in a test using a 25 mm sample cube at 140 ° C (284 ° F). |
| 2 | A negative result is obtained in a test using a 25 mm cube sample at 140 ° C (284 ° F), a positive result is obtained in a test using a 100 mm sample cube at 140 ° C (284 ° F), and: |
| (a) The unit volume of the chemical is more than 3 m3; or | |
| (b) A positive result is obtained in a test using a 100 mm cube sample at 120 ° C (248 ° F) and the unit volume of the chemical is more than 450 liters; or | |
| (c) A positive result is obtained in a test using a 100 mm cube sample at 100 ° C (212 ° F). |
B.11.2.2 Chemicals with a temperature of spontaneous combustion higher than 50 ° C (122 ° F) for a volume of 27 m3 shall not be classified as self-heating chemicals.
B.11.2.3 Chemicals with a spontaneous ignition temperature higher than 50° C (122° F) for a volume of 450 liters shall not be classified in Category 1 of this class.
B.11.3 Additional Classification Considerations
B.11.3.1 The classification procedure for self-heating chemicals need not be applied if the results of a screening test can be adequately correlated with the classification test and an appropriate safety margin is applied.
B.11.3.2 Examples of screening tests are:
Harper, D. J. Rogers, R. Evaluation of the fire and explosion risks in drying powders, Plant Operations Progress, 4 (3), 181-189, 1985) with an onset temperature 60°K above the reference temperature for a volume of 1 l.
B.12 Chemicals Which, in Contact With Water, Emit Flammable Gases
B.12.1 Definition
Chemicals which, in contact with water, emit flammable gases are solid or liquid chemicals which, by interaction with water, are liable to become spontaneously flammable or to give off flammable gases in dangerous quantities.
B.12.2 Classification Criteria
B.12.2.1 A chemical which, in contact with water, emits flammable gases shall be classified in one of the three categories for this class, using test N.5 in Part III, sub-section 33.4.1.4 of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6), in accordance with Table B.12.1 of this appendix:
| Category | Criteria |
|---|---|
| 1 | Any chemical which reacts vigorously with water at ambient temperatures and demonstrates generally a tendency for the gas produced to ignite spontaneously, or which reacts readily with water at ambient temperatures such that the rate of evolution of flammable gas is equal to or greater than 10 liters per kilogram of chemical over any one minute. |
| 2 | Any chemical which reacts readily with water at ambient temperatures such that the maximum rate of evolution of flammable gas is equal to or greater than 20 liters per kilogram of chemical per hour, and which does not meet the criteria for Category 1. |
| 3 | Any chemical which reacts slowly with water at ambient temperatures such that the maximum rate of evolution of flammable gas is greater than 1 liter per kilogram of chemical per hour, and which does not meet the criteria for Categories 1 and 2. |
| Note: Classification of solid chemicals shall be based on tests performed on the chemical as presented. If, for example, for the purposes of supply or transport, the same chemical is to be presented in a physical form different from that which was tested and which is considered likely to materially alter its performance in a classification test, classification must be based on testing of the chemical in the new form. |
B.12.2.2 A chemical is classified as a chemical which, in contact with water, emits flammable gases if spontaneous ignition takes place in any step of the test procedure.
B.12.3 Additional Classification Considerations
The classification procedure for this class need not be applied if:
B.13 Oxidizing Liquids
B.13.1 Definition
Oxidizing liquid means a liquid which, while in itself not necessarily combustible, may, generally by yielding oxygen, cause, or contribute to, the combustion of other material.
B.13.2 Classification Criteria
An oxidizing liquid shall be classified in one of the three categories for this class using test O.2 in Part III, sub-section 34.4.2 of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6), in accordance with Table B.13.1:
| Category | Criteria |
|---|---|
| 1 | Any chemical which, in the 1:1 mixture, by mass, of chemical and cellulose tested, spontaneously ignites; or the mean pressure rise time of a 1:1 mixture, by mass, of chemical and cellulose is less than that of a 1:1 mixture, by mass, of 50% perchloric acid and cellulose; |
| 2 | Any chemical which, in the 1:1 mixture, by mass, of chemical and cellulose tested, exhibits a mean pressure rise time less than or equal to the mean pressure rise time of a 1:1 mixture, by mass, of 40% aqueous sodium chlorate solution and cellulose; and the criteria for Category 1 are not met; |
| 3 | Any chemical which, in the 1:1 mixture, by mass, of chemical and cellulose tested, exhibits a mean pressure rise time less than or equal to the mean pressure rise time of a 1:1 mixture, by mass, of 65% aqueous nitric acid and cellulose; and the criteria for Categories 1 and 2 are not met. |
B.13.3 Additional Classification Considerations
B.13.3.1 For organic chemicals, the classification procedure for this class shall not be applied if:
B.13.3.2 For inorganic chemicals, the classification procedure for this class shall not be applied if the chemical does not contain oxygen or halogen atoms.
B.13.3.3 In the event of divergence between test results and known experience in the handling and use of chemicals which shows them to be oxidizing, judgments based on known experience shall take precedence over test results.
B.13.3.4 In cases where chemicals generate a pressure rise (too high or too low), caused by chemical reactions not characterizing the oxidizing properties of the chemical, the test described in Part III, sub-section 34.4.2 of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6) shall be repeated with an inert substance ( e.g., diatomite (kieselguhr)) in place of the cellulose in order to clarify the nature of the reaction.
B.14 Oxidizing Solids
B.14.1 Definition
Oxidizing solid means a solid which, while in itself is not necessarily combustible, may, generally by yielding oxygen, cause, or contribute to, the combustion of other material.
B.14.2 Classification Criteria
An oxidizing solid shall be classified in one of the three categories for this class using test O.1 in Part III, sub-section 34.4.1, of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6) or test O.3 in Part III, sub-section 34.4.3 of UN ST/SG/AC.10/11 (incorporated by reference, see § 1910.6), in accordance with Table B.14.1:
| Category | Criteria using test O.1 | Criteria using test O.3 |
|---|---|---|
| 1 | Any chemical which, in the 4:1 or 1:1 sample-to-cellulose ratio (by mass) tested, exhibits a mean burning time less than the mean burning time of a 3:2 mixture, (by mass), of potassium bromate and cellulose | Any chemical which, in the 4:1 or 1:1 sample-to- cellulose ratio (by mass) tested, exhibits a mean burning rate greater than the mean burning rate of a 3:1 mixture (by mass) of calcium peroxide and cellulose. |
| 2 | Any chemical which, in the 4:1 or 1:1 sample-to-cellulose ratio (by mass) tested, exhibits a mean burning time equal to or less than the mean burning time of a 2:3 mixture (by mass) of potassium bromate and cellulose and the criteria for Category 1 are not met | Any chemical which, in the 4:1 or 1:1 sample-to- cellulose ratio (by mass) tested, exhibits a mean burning rate equal to or greater than the mean burning rate of a 1:1 mixture (by mass) of calcium peroxide and cellulose and the criteria for Category 1 are not met. |
| 3 | Any chemical which, in the 4:1 or 1:1 sample-to-cellulose ratio (by mass) tested, exhibits a mean burning time equal to or less than the mean burning time of a 3:7 mixture (by mass) of potassium bromate and cellulose and the criteria for Categories 1 and 2 are not met | Any chemical which, in the 4:1 or 1:1 sample-to- cellulose ratio (by mass) tested, exhibits a mean burning rate equal to or greater than the mean burning rate of a 1:2 mixture (by mass) of calcium peroxide and cellulose and the criteria for Categories 1 and 2 are not met. |
B.14.3 Additional Classification Considerations
B.14.3.1 For organic chemicals, the classification procedure for this class shall not be applied if:
B.14.3.2 For inorganic chemicals, the classification procedure for this class shall not be applied if the chemical does not contain oxygen or halogen atoms.
B.14.3.3 In the event of divergence between test results and known experience in the handling and use of chemicals which shows them to be oxidizing, judgements based on known experience shall take procedure over test results.
B.15 Organic Peroxides
B.15.1 Definition
B.15.1.1 Organic peroxide means a liquid or solid organic chemical which contains the bivalent -0-0- structure and as such is considered a derivative of hydrogen peroxide, where one or both of the hydrogen atoms have been replaced by organic radicals. The term organic peroxide includes organic peroxide mixtures containing at least one organic peroxide. Organic peroxides are thermally unstable chemicals, which may undergo exothermic self-accelerating decomposition. In addition, they may have one or more of the following properties:
B.15.1.2 An organic peroxide is regarded as possessing explosive properties when in laboratory testing the formulation is liable to detonate, to deflagrate rapidly or to show a violent effect when heated under confinement.
B.15.2 Classification Criteria
B.15.2.1 Any organic peroxide shall be considered for classification in this class, unless it contains:
where:
ni = number of peroxygen groups per molecule of organic peroxide i;
ci = concentration (mass %) of organic peroxide i;
mi = molecular mass of organic peroxide i.
B.15.2.2 Organic peroxides shall be classified in one of the seven categories of “Types A to G” for this class, according to the following principles:
B.15.3 Additional Classification Considerations
B.15.3.1 For purposes of classification, the properties of organic peroxides shall be determined in accordance with test series A to H as described in Part II of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6).
B.15.3.2 Self-accelerating decomposition temperature (SADT) shall be determined in accordance with UN ST/SG/AC.10 (incorporated by reference, see § 1910.6), Part II, section 28.
B.15.3.3 Mixtures of organic peroxides may be classified as the same type of organic peroxide as that of the most dangerous ingredient. However, as two stable ingredients can form a thermally less stable mixture, the SADT of the mixture shall be determined.
B.16 Corrosive to Metals
B.16.1 Definition
A chemical which is corrosive to metals means a chemical which by chemical action will materially damage, or even destroy, metals.
B.16.2 Classification Criteria
A chemical which is corrosive to metals shall be classified in a single category for this class, using the test in Part III, sub-section 37.4 of UN ST/SG/AC.10 (incorporated by reference, see § 1910.6), in accordance with Table B.16.1:
| Category | Criteria |
|---|---|
| 1 | Corrosion rate on either steel or aluminum surfaces exceeding 6.25 mm per year at a test temperature of 55 ° C (131 ° F) when tested on both materials. |
B.16.3 Additional Classification Considerations
The specimen to be used for the test shall be made of the following materials:
non-clad types 7075-T6 or AZ5GU-T6.
B.17 Desensitized Explosives
B.17.1 Definitions and General Considerations
Desensitized explosives are solid or liquid explosive chemicals which are phlegmatized 2 to suppress their explosive properties in such a manner that they do not mass explode and do not burn too rapidly and therefore may be exempted from the hazard class “Explosives” (Chapter B.1; see also Note 2 of paragraph B.1.3). 3
2 Phlegmatized means that a substance (or “phlegmatizer”) has been added to an explosive to enhance its safety in handling and transport. The phlegmatizer renders the explosive insensitive, or less sensitive, to the following actions: heat, shock, impact, percussion or friction. Typical phlegmatizing agents include, but are not limited to: wax, paper, water, polymers (such as chlorofluoropolymers), alcohol and oils (such as petroleum jelly and paraffin).
3 Unstable explosives as defined in Chapter B.1 can also be stabilized by desensitization and consequently may be re-classified as desensitized explosives, provided all criteria of Chapter B.17 are met. In this case, the desensitized explosive should be tested according to Test Series 3 (Part I of UN ST/SG/AC.10/11/Rev. 6 (incorporated by reference, see § 1910.6)) because information about its sensitiveness to mechanical stimuli is likely to be important for determining conditions for safe handling and use. The results shall be communicated on the safety data sheet.
B.17.1.1 The class of desensitized explosives comprises:
explosive substances or mixtures which are wetted with water or alcohols or are diluted with other substances, to form a homogeneous solid mixture to suppress their explosive properties.
explosive substances or mixtures which are dissolved or suspended in water or other liquid substances, to form a homogeneous liquid mixture to suppress their explosive properties.
B.17.2 Classification Criteria
B.17.2.1 Any explosive which is desensitized shall be considered in this class, unless:
It has a mass explosion hazard according to test series 6 (a) or 6 (b) or its corrected burning rate according to the burning rate test described in part V, subsection 51.4 of UN ST/SG/AC.10/11/Rev.6 (incorporated by reference, see § 1910.6) is greater than 1200 kg/min; or
B.17.2.2 Desensitized explosives shall be classified in one of the four categories of this class depending on the corrected burning rate (Ac) using the test “burning rate test (external fire)” described in Part V, sub-section 51.4 of UN ST/SG/AC.10/11/Rev.6 (incorporated by reference, see § 1910.6), according to Table B.17.1:
| Category | Criteria |
|---|---|
| 1 | Desensitized explosives with a corrected burning rate (AC) equal to or greater than 300 kg/min but not more than 1200 kg/min. |
| 2 | Desensitized explosives with a corrected burning rate (AC) equal to or greater than 140 kg/min but less than 300 kg/min. |
| 3 | Desensitized explosives with a corrected burning rate (AC) equal to or greater than 60 kg/min but less than 140 kg/min. |
| 4 | Desensitized explosives with a corrected burning rate (AC) less than 60 kg/min. |
B.17.3 Additional Classification Considerations
B.17.3.1 The classification procedure for desensitized explosives does not apply if:
B.17.3.2 The exothermic decomposition energy shall be determined using the explosive already desensitized ( i.e., the homogenous solid or liquids mixture formed by the explosive and the substance(s) used to suppress its explosive properties). The exothermic decomposition energy may be estimated using a suitable calorimetric technique ( see Section 20, sub-section 20.3.3.3 in Part II of UN ST/SG/AC.10/11/Rev. 6 (incorporated by reference, see § 1910.6).
Appendix C to § 1910.1200—Allocation of Label Elements (Mandatory)
C.1 The label for each hazardous chemical shall include the product identifier used on the safety data sheet.
C.1.1 The labels on shipped containers shall also include the name, address, and telephone number of the chemical manufacturer, importer, or responsible party.
C.2 The label for each hazardous chemical that is classified shall include the signal word, hazard statement(s), pictogram(s), and precautionary statement(s) specified in C.4 for each hazard class and associated hazard category, except as provided for in C.2.1 through C.2.4.
C.2.1 Precedence of Hazard Information
C.2.1.1 If the signal word “Danger” is included, the signal word “Warning” shall not appear;
C.2.1.2 If the skull and crossbones pictogram is included, the exclamation mark pictogram shall not appear where it is used for acute toxicity;
C.2.1.3 If the corrosive pictogram is included, the exclamation mark pictogram shall not appear where it is used for skin or eye irritation;
C.2.1.4 If the health hazard pictogram is included for respiratory sensitization, the exclamation mark pictogram shall not appear where it is used for skin sensitization or for skin or eye irritation.
C.2.2 Hazard Statement Text
C.2.2.1 The text of all applicable hazard statements shall appear on the label, except as otherwise specified. The information in italics shall be included as part of the hazard statement as provided. For example: “causes damage to organs (state all organs affected) through prolonged or repeated exposure (state route of exposure if no other routes of exposure cause the hazard)”. Hazard statements may be combined where appropriate to reduce the information on the label and improve readability, as long as all of the hazards are conveyed as required.
C.2.2.2 If the chemical manufacturer, importer, or responsible party can demonstrate that all or part of the hazard statement is inappropriate to a specific substance or mixture, the corresponding statement may be omitted from the label.
C.2.3 Pictograms
C.2.3.1 Pictograms shall be in the shape of a square set at a point and shall include a black hazard symbol on a white background with a red frame sufficiently wide to be clearly visible. A square red frame set at a point without a hazard symbol is not a pictogram and is not permitted on the label.
C.2.3.2 One of eight standard hazard symbols shall be used in each pictogram. The eight hazard symbols are depicted in Figure C.1. A pictogram using the exclamation mark symbol is presented in Figure C.2, for the purpose of illustration.
C.2.3.3 The exclamation mark pictogram is permitted (but not required) for HNOCs as long as the words “Hazard Not Otherwise Classified” or the letters “HNOC” appear below the pictogram.
C.2.3.4 Pictograms may only appear once on a label. If multiple hazards require the use of the same pictogram, it may not appear a second time on the label.
C.2.4 Precautionary Statement Text
C.2.4.1 There are four types of precautionary statements presented, “prevention,” “response,” “storage,” and “disposal.” The core part of the precautionary statement is presented in bold print. This is the text, except as otherwise specified, that shall appear on the label. Where additional information is required, it is indicated in plain text.
C.2.4.2 When a backslash or diagonal mark (/) appears in the precautionary statement text, it indicates that a choice has to be made between the separated phrases. In such cases, the chemical manufacturer, importer, or responsible party can choose the most appropriate phrase(s). For example, “Wear protective gloves/protective clothing/eye protection/face protection” could read “wear eye protection”.
C.2.4.3 When three full stops (...) appear in the precautionary statement text, they indicate that all applicable conditions are not listed. For example, in “Use explosion-proof electrical/ventilating/lighting/.../equipment”, the use of “...” indicates that other equipment may need to be specified. In such cases, the chemical manufacturer, importer, or responsible party can choose the other conditions to be specified.
C.2.4.4 When text in italics is used in a precautionary statement, this indicates specific conditions applying to the use or allocation of the precautionary statement. For example, “Use explosion-proof electrical/ventilating/lighting/.../equipment” is only required for flammable solids “ if dust clouds can occur ”. Text in italics is intended to be an explanatory, conditional note and is not intended to appear on the label.
C.2.4.5 Where square brackets ([ ]) appear around text in a precautionary statement, this indicates that the text in square brackets is not appropriate in every case and should be used only in certain circumstances. In these cases, conditions for use explaining when the text should be used are provided. For example, one precautionary statement states: “[In case of inadequate ventilation] wear respiratory protection.” This statement is given with the condition for use “- text in square brackets may be used if additional information is provided with the chemical at the point of use that explains what type of ventilation would be adequate for safe use”. This means that, if additional information is provided with the chemical explaining what type of ventilation would be adequate for safe use, the text in square brackets should be used and the statement would read: “In case of inadequate ventilation wear respiratory protection.” However, if the chemical is supplied without such ventilation information, the text in square brackets should not be used, and the precautionary statement should read: “Wear respiratory protection.”
C.2.4.6 Precautionary statements may be combined or consolidated to save label space and improve readability. For example, “Keep cool” and “Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.” can be combined to read “Keep cool and away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.”
C.2.4.7 Precautionary statements may incorporate minor textual variations from the text prescribed in this Appendix if these variations assist in communicating safety information ( e.g., spelling variations, synonyms or other equivalent terms) and the safety advice is not diluted or compromised. Any variations must be used consistently on the label and the safety data sheet.
C.2.4.8 In most cases, the precautionary statements are independent ( e.g., the phrases for explosives hazards do not modify those related to certain health hazards, and products that are classified for both hazard classes shall bear appropriate precautionary statements for both). Where a chemical is classified for a number of hazards, and the precautionary statements are similar, the most stringent shall be included on the label (this will be applicable mainly to preventive measures).
C.2.4.9 If the chemical manufacturer, importer, or responsible party can demonstrate that a precautionary statement is inappropriate to a specific substance or mixture, the precautionary statement may be omitted from the label.
C.2.4.10 Where a substance or mixture is classified for a number of health hazards, this may trigger multiple precautionary statements relating to medical response, e.g., calling a poison center/doctor/... and getting medical advice/attention.
In general, the following principles should be applied:
C.3 Supplementary Hazard Information
C.3.1 To ensure that non-standardized information does not lead to unnecessarily wide variation or undermine the required information, supplementary information on the label is limited to when it provides further detail and does not contradict or cast doubt on the validity of the standardized hazard information.
C.3.2 Where the chemical manufacturer, importer, or distributor chooses to add supplementary information on the label, the placement of supplemental information shall not impede identification of information required by this section.
C.3.3 Where an ingredient with unknown acute toxicity is used in a mixture at a concentration ≥1%, and the mixture is not classified based on testing of the mixture as a whole, a statement that X% of the mixture consists of ingredient(s) of unknown acute toxicity (oral/dermal/inhalation) is required on the label and safety data sheet.
C.4 Requirements for Signal Words, Hazard Statements, Pictograms, and Precautionary Statements
Appendix E to § 1910.1200—Definition of “Trade Secret” (Mandatory)
The following is a reprint of the Restatement of Torts section 757, comment b (1939):
b. Definition of trade secret. A trade secret may consist of any formula, pattern, device or compilation of information which is used in one's business, and which gives him an opportunity to obtain an advantage over competitors who do not know or use it. It may be a formula for a chemical compound, a process of manufacturing, treating or preserving materials, a pattern for a machine or other device, or a list of customers. It differs from other secret information in a business (see s759 of the Restatement of Torts which is not included in this Appendix) in that it is not simply information as to single or ephemeral events in the conduct of the business, as, for example, the amount or other terms of a secret bid for a contract or the salary of certain employees, or the security investments made or contemplated, or the date fixed for the announcement of a new policy or for bringing out a new model or the like. A trade secret is a process or device for continuous use in the operations of the business. Generally it relates to the production of goods, as, for example, a machine or formula for the production of an article. It may, however, relate to the sale of goods or to other operations in the business, such as a code for determining discounts, rebates or other concessions in a price list or catalogue, or a list of specialized customers, or a method of bookkeeping or other office management.
Secrecy. The subject matter of a trade secret must be secret. Matters of public knowledge or of general knowledge in an industry cannot be appropriated by one as his secret. Matters which are completely disclosed by the goods which one markets cannot be his secret. Substantially, a trade secret is known only in the particular business in which it is used. It is not requisite that only the proprietor of the business know it. He may, without losing his protection, communicate it to employees involved in its use. He may likewise communicate it to others pledged to secrecy. Others may also know of it independently, as, for example, when they have discovered the process or formula by independent invention and are keeping it secret. Nevertheless, a substantial element of secrecy must exist, so that, except by the use of improper means, there would be difficulty in acquiring the information. An exact definition of a trade secret is not possible. Some factors to be considered in determining whether given information is one's trade secret are: (1) The extent to which the information is known outside of his business; (2) the extent to which it is known by employees and others involved in his business; (3) the extent of measures taken by him to guard the secrecy of the information; (4) the value of the information to him and his competitors; (5) the amount of effort or money expended by him in developing the information; (6) the ease or difficulty with which the information could be properly acquired or duplicated by others.
Novelty and prior art. A trade secret may be a device or process which is patentable; but it need not be that. It may be a device or process which is clearly anticipated in the prior art or one which is merely a mechanical improvement that a good mechanic can make. Novelty and invention are not requisite for a trade secret as they are for patentability. These requirements are essential to patentability because a patent protects against unlicensed use of the patented device or process even by one who discovers it properly through independent research. The patent monopoly is a reward to the inventor. But such is not the case with a trade secret. Its protection is not based on a policy of rewarding or otherwise encouraging the development of secret processes or devices. The protection is merely against breach of faith and reprehensible means of learning another's secret. For this limited protection it is not appropriate to require also the kind of novelty and invention which is a requisite of patentability. The nature of the secret is, however, an important factor in determining the kind of relief that is appropriate against one who is subject to liability under the rule stated in this Section. Thus, if the secret consists of a device or process which is a novel invention, one who acquires the secret wrongfully is ordinarily enjoined from further use of it and is required to account for the profits derived from his past use. If, on the other hand, the secret consists of mechanical improvements that a good mechanic can make without resort to the secret, the wrongdoer's liability may be limited to damages, and an injunction against future use of the improvements made with the aid of the secret may be inappropriate.
Appendix F to § 1910.1200—Guidance for Hazard Classifications Re: Carcinogenicity (Non-Mandatory)
The mandatory criteria for classification of a chemical for carcinogenicity under HCS (§ 1910.1200) are found in Appendix A.6 to this section. This non-mandatory Appendix provides additional guidance on hazard classification for carcinogenicity. Part A of Appendix F includes background guidance provided by GHS based on the Preamble of the International Agency for Research on Cancer (IARC) “Monographs on the Evaluation of Carcinogenic Risks to Humans” (2006). Part B provides IARC classification information. Part C provides background guidance from the National Toxicology Program (NTP) “Report on Carcinogens” (RoC), and Part D is a table that compares GHS carcinogen hazard categories to carcinogen classifications under IARC and NTP, allowing classifiers to be able to use information from IARC and NTP RoC carcinogen classifications to complete their classifications under the GHS, and thus the HCS.
Part A: Background Guidance 1
1 The text of Appendix F, Part A, on the IARC Monographs, is paraphrased from the 2006 Preamble to the “Monographs on the Evaluation of Carcinogenic Risks to Humans”; the Classifier is referred to the full IARC Preamble for the complete text. The text is not part of the agreed GHS text on the harmonized system developed by the OECD Task Force-HCL.
As noted in Footnote 6 of Appendix A.6. to this section, the GHS includes as guidance for classifiers information taken from the Preamble of the International Agency for Research on Cancer (IARC) “Monographs on the Evaluation of Carcinogenic Risks to Humans” (2006), providing guidance on the evaluation of the strength and evidence of carcinogenic risks to humans. This guidance also discusses some additional considerations in classification and an approach to analysis, rather than hard-and-fast rules. Part A is consistent with Appendix A.6, and should help in evaluating information to determine carcinogenicity.
Carcinogenicity in humans:
The evidence relevant to carcinogenicity from studies in humans is classified into one of the following categories:
A causal relationship has been established between exposure to the agent and human cancer. That is, a positive relationship has been observed between the exposure and cancer in studies in which chance, bias and confounding could be ruled out with reasonable confidence.
A positive association has been observed between exposure to the agent and cancer for which a causal interpretation is considered by the Working Group to be credible, but chance, bias or confounding could not be ruled out with reasonable confidence.
In some instances, the above categories may be used to classify the degree of evidence related to carcinogenicity in specific organs or tissues.
Carcinogenicity in experimental animals:
The evidence relevant to carcinogenicity in experimental animals is classified into one of the following categories:
A causal relationship has been established between the agent and an increased incidence of malignant neoplasms or of an appropriate combination of benign and malignant neoplasms in two or more species of animals or two or more independent studies in one species carried out at different times or in different laboratories or under different protocols. An increased incidence of tumors in both sexes of a single species in a well-conducted study, ideally conducted under Good Laboratory Practices, can also provide sufficient evidence.
Exceptionally, a single study in one species and sex might be considered to provide sufficient evidence of carcinogenicity when malignant neoplasms occur to an unusual degree with regard to incidence, site, type of tumor or age at onset, or when there are strong findings of tumors at multiple sites.
The data suggest a carcinogenic effect but are limited for making a definitive evaluation because, e.g. the evidence of carcinogenicity is restricted to a single experiment; there are unresolved questions regarding the adequacy of the design, conduct or interpretation of the studies; the agent increases the incidence only of benign neoplasms or lesions of uncertain neoplastic potential; or the evidence of carcinogenicity is restricted to studies that demonstrate only promoting activity in a narrow range of tissues or organs.
[59 FR 6170, Feb. 9, 1994, as amended at 59 FR 17479, Apr. 13, 1994; 59 FR 65948, Dec. 22, 1994; 61 FR 9245, Mar. 7, 1996; 77 FR 17785, Mar. 26, 2012; 78 FR 9313, Feb. 8, 2013; 89 FR 44356, May 20, 2024; 89 FR 81830, Oct. 9, 2024; 91 FR 565, Jan. 8, 2026; 91 FR 1696, Jan. 15, 2026; 91 FR 6760, Feb. 13, 2026]
Guidance on How To Consider Important Factors in Classification of Carcinogenicity (See Reference Section)
The weight of evidence analysis called for in GHS and the HCS (§ 1910.1200) is an integrative approach that considers important factors in determining carcinogenic potential along with the strength of evidence analysis. The IPCS “ Conceptual Framework for Evaluating a Mode of Action for Chemical Carcinogenesis” (2001), International Life Sciences Institute (ILSI) “ Framework for Human Relevance Analysis of Information on Carcinogenic Modes of Action” (Meek, et al., 2003; Cohen et al., 2003, 2004), and Preamble to the IARC Monographs (2006; Section B.6. (Scientific Review and Evaluation; Evaluation and Rationale)) provide a basis for systematic assessments that may be performed in a consistent fashion. The IPCS also convened a panel in 2004 to further develop and clarify the human relevance framework. However, the above documents are not intended to dictate answers, nor provide lists of criteria to be checked off.
Mode of Action
Various documents on carcinogen assessment all note that mode of action in and of itself, or consideration of comparative metabolism, should be evaluated on a case-by-case basis and are part of an analytic evaluative approach. One must look closely at any mode of action in animal experiments, taking into consideration comparative toxicokinetics/toxicodynamics between the animal test species and humans to determine the relevance of the results to humans. This may lead to the possibility of discounting very specific effects of certain types of substances. Life stage-dependent effects on cellular differentiation may also lead to qualitative differences between animals and humans. Only if a mode of action of tumor development is conclusively determined not to be operative in humans may the carcinogenic evidence for that tumor be discounted. However, a weight of evidence evaluation for a substance calls for any other tumorigenic activity to be evaluated, as well.
Responses in Multiple Animal Experiments
Positive responses in several species add to the weight of evidence that a substance is a carcinogen. Taking into account all of the factors listed in A.6.2.5.2 and more, such chemicals with positive outcomes in two or more species would be provisionally considered to be classified in GHS Category 1B until human relevance of animal results are assessed in their entirety. It should be noted, however, that positive results for one species in at least two independent studies, or a single positive study showing unusually strong evidence of malignancy may also lead to Category 1B.
Responses Are in One Sex or Both Sexes
Any case of sex-specific tumors should be evaluated in light of the total tumorigenic response to the substance observed at other sites (multi-site responses or incidence above background) in determining the carcinogenic potential of the substance.
If tumors are seen only in one sex of an animal species, the mode of action should be carefully evaluated to see if the response is consistent with the postulated mode of action. Effects seen only in one sex in a test species may be less convincing than effects seen in both sexes, unless there is a clear patho-physiological difference consistent with the mode of action to explain the single sex response.
Confounding Effects of Excessive Toxicity or Localized Effects
Tumors occurring only at excessive doses associated with severe toxicity generally have doubtful potential for carcinogenicity in humans. In addition, tumors occurring only at sites of contact and/or only at excessive doses need to be carefully evaluated for human relevance for carcinogenic hazard. For example, forestomach tumors, following administration by gavage of an irritating or corrosive, non-mutagenic chemical, may be of questionable relevance. However, such determinations must be evaluated carefully in justifying the carcinogenic potential for humans; any occurrence of other tumors at distant sites must also be considered.
Tumor Type, Reduced Tumor Latency
Unusual tumor types or tumors occurring with reduced latency may add to the weight of evidence for the carcinogenic potential of a substance, even if the tumors are not statistically significant.
Toxicokinetic behavior is normally assumed to be similar in animals and humans, at least from a qualitative perspective. On the other hand, certain tumor types in animals may be associated with toxicokinetics or toxicodynamics that are unique to the animal species tested and may not be predictive of carcinogenicity in humans. Very few such examples have been agreed internationally. However, one example is the lack of human relevance of kidney tumors in male rats associated with compounds causing α2u-globulin nephropathy (IARC, Scientific Publication N° 147 2 ). Even when a particular tumor type may be discounted, expert judgment must be used in assessing the total tumor profile in any animal experiment.
2 While most international agencies do not consider kidney tumors coincident with α2u-globulin nephropathy to be a predictor of risk in humans, this view is not universally held. (See: Doi et al., 2007).
Part B: International Agency for Research on Cancer (IARC) 3
3 Preamble of the International Agency for Research on Cancer (IARC) “Monographs on the Evaluation of Carcinogenic Risks to Humans” (2006).
IARC Carcinogen Classification Categories:
Group 1: The agent is carcinogenic to humans
This category is used when there is sufficient evidence of carcinogenicity in humans. Exceptionally, an agent may be placed in this category when evidence of carcinogenicity in humans is less than sufficient but there is sufficient evidence of carcinogenicity in experimental animals and strong evidence in exposed humans that the agent acts through a relevant mechanism of carcinogenicity.
Group 2:
This category includes agents for which, at one extreme, the degree of evidence of carcinogenicity in humans is almost sufficient, as well as those for which, at the other extreme, there are no human data but for which there is evidence of carcinogenicity in experimental animals. Agents are assigned to either Group 2A ( probably carcinogenic to humans ) or Group 2B ( possibly carcinogenic to humans ) on the basis of epidemiological and experimental evidence of carcinogenicity and mechanistic and other relevant data. The terms probably carcinogenic and possibly carcinogenic have no quantitative significance and are used simply as descriptors of different levels of evidence of human carcinogenicity, with probably carcinogenic signifying a higher level of evidence than possibly carcinogenic.
Group 2A: The agent is probably carcinogenic to human.
This category is used when there is limited evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals. In some cases, an agent may be classified in this category when there is inadequate evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals and strong evidence that the carcinogenesis is mediated by a mechanism that also operates in humans. Exceptionally, an agent may be classified in this category solely on the basis of limited evidence of carcinogenicity in humans. An agent may be assigned to this category if it clearly belongs, based on mechanistic considerations, to a class of agents for which one or more members have been classified in Group 1 or Group 2A.
Group 2B: The agent is possibly carcinogenic to humans.
This category is used for agents for which there is limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals. It may also be used when there is inadequate evidence of carcinogenicity in humans but there is sufficient evidence of carcinogenicity in experimental animals. In some instances, an agent for which there is inadequate evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals together with supporting evidence from mechanistic and other relevant data may be placed in this group. An agent may be classified in this category solely on the basis of strong evidence from mechanistic and other relevant data.
Part C: National Toxicology Program (NTP), “Report on Carcinogens”, Background Guidance
NTP Listing Criteria 4
4 See: http://ntp.niehs.nih.gov/go/15209.
The criteria for listing an agent, substance, mixture, or exposure circumstance in the Report on Carcinogens (RoC) are as follows:
Known To Be A Human Carcinogen: There is sufficient evidence of carcinogenicity from studies in humans 5 that indicates a causal relationship between exposure to the agent, substance, or mixture, and human cancer.
5 This evidence can include traditional cancer epidemiology studies, data from clinical studies, and/or data derived from the study of tissues or cells from humans exposed to the substance in question that can be useful for evaluating whether a relevant cancer mechanism is operating in people.
Reasonably Anticipated To Be A Human Carcinogen: There is limited evidence of carcinogenicity from studies in humans that indicates that a causal interpretation is credible, but that alternative explanations, such as chance, bias, or confounding factors, could not adequately be excluded,
or
there is sufficient evidence of carcinogenicity from studies in experimental animals that indicates there is an increased incidence of malignant and/or a combination of malignant and benign tumors in multiple species or at multiple tissue sites, or by multiple routes of exposure, or to an unusual degree with regard to incidence, site, or type of tumor, or age at onset,
or
there is less than sufficient evidence of carcinogenicity in humans or laboratory animals; however, the agent, substance, or mixture belongs to a well-defined, structurally-related class of substances whose members are listed in a previous Report on Carcinogens as either known to be a human carcinogen or reasonably anticipated to be a human carcinogen, or there is convincing relevant information that the agent acts through mechanisms indicating it would likely cause cancer in humans.
Conclusions regarding carcinogenicity in humans or experimental animals are based on scientific judgment, with consideration given to all relevant information. Relevant information includes, but is not limited to, dose response, route of exposure, chemical structure, metabolism, pharmacokinetics, sensitive sub-populations, genetic effects, or other data relating to mechanism of action or factors that may be unique to a given substance. For example, there may be substances for which there is evidence of carcinogenicity in laboratory animals, but there are compelling data indicating that the agent acts through mechanisms that do not operate in humans and would therefore not reasonably be anticipated to cause cancer in humans.
Part D: Table Relating Approximate Equivalences Among IARC, NTP RoC, and GHS Carcinogenicity Classifications
The following table may be used to perform hazard classifications for carcinogenicity under the HCS (§ 1910.1200). It relates the approximated GHS hazard categories for carcinogenicity to the classifications provided by IARC and NTP, as described in Parts B and C of this Appendix.
| IARC | GHS | NTP RoC |
|---|---|---|
| Group 1 | Category 1A | Known. |
| Group 2A | Category 1B | Reasonably Anticipated (See Note 1). |
| Group 2B | Category 2 | Reasonably Anticipated (See Note 1). |
Note 1:
1. Limited evidence of carcinogenicity from studies in humans (corresponding to IARC 2A/GHS 1B);
2. Sufficient evidence of carcinogenicity from studies in experimental animals (again, essentially corresponding to IARC 2A/GHS 1B);
3. Less than sufficient evidence of carcinogenicity in humans or laboratory animals; however:
a. The agent, substance, or mixture belongs to a well-defined, structurally-related class of substances whose members are listed in a previous RoC as either “Known” or “Reasonably Anticipated” to be a human carcinogen, or
b. There is convincing relevant information that the agent acts through mechanisms indicating it would likely cause cancer in humans.
*References
Toxicol. Sci.
Crit. Rev. Toxicol.
Crit. Rev. Toxicol.
Reg. Toxicol. Pharm.
International Programme on Chemical Safety Harmonization Group. 2004. Report of the First Meeting of the Cancer Working Group. World Health Organization. Report IPCS/HSC-CWG-1/04. Geneva.
International Agency for Research on Cancer. IARC Monographs on the Evaluation of Carcinogenic Risks to Human. Preambles to Volumes. World Health Organization. Lyon, France.
Cohen, S.M., P.A. Fenner-Crisp, and D.E. Patton. 2003. Special Issue: Cancer Modes of Action and Human Relevance. Critical Reviews in Toxicology, R.O. McClellan, ed., Volume 33/Issue 6. CRC Press.
Capen, C.C., E. Dybing, and J.D. Wilbourn. 1999. Species differences in thyroid, kidney and urinary bladder carcinogenesis. International Agency for Research on Cancer, Scientific Publication N° 147.
Toxicol. Pathol.
[59 FR 36700, July 19, 1994]
Action level means a concentration designated in 29 CFR part 1910 for a specific substance, calculated as an eight (8)-hour time-weighted average, which initiates certain required activities such as exposure monitoring and medical surveillance.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Carcinogen (see select carcinogen ).
Chemical Hygiene Officer means an employee who is designated by the employer, and who is qualified by training or experience, to provide technical guidance in the development and implementation of the provisions of the Chemical Hygiene Plan. This definition is not intended to place limitations on the position description or job classification that the designated indvidual shall hold within the employer's organizational structure.
Chemical Hygiene Plan means a written program developed and implemented by the employer which sets forth procedures, equipment, personal protective equipment and work practices that (i) are capable of protecting employees from the health hazards presented by hazardous chemicals used in that particular workplace and (ii) meets the requirements of paragraph (e) of this section.
Designated area means an area which may be used for work with “select carcinogens,” reproductive toxins or substances which have a high degree of acute toxicity. A designated area may be the entire laboratory, an area of a laboratory or a device such as a laboratory hood.
Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers or failure of control equipment which results in an uncontrolled release of a hazardous chemical into the workplace.
Employee means an individual employed in a laboratory workplace who may be exposed to hazardous chemicals in the course of his or her assignments.
Hazardous chemical means any chemical which is classified as health hazard or simple asphyxiant in accordance with the Hazard Communication Standard (§ 1910.1200).
Health hazard means a chemical that is classified as posing one of the following hazardous effects: Acute toxicity (any route of exposure); skin corrosion or irritation; serious eye damage or eye irritation; respiratory or skin sensitization; germ cell mutagenicity; carcinogenity; reproductive toxicity; specific target organ toxicity (single or repeated exposure); aspiration hazard. The criteria for determining whether a chemical is classified as a health hazard are detailed in appendix A of the Hazard Communication Standard (§ 1910.1200) and § 1910.1200(c) (definition of “simple asphyxiant”).
Laboratory means a facility where the “laboratory use of hazardous chemicals” occurs. It is a workplace where relatively small quantities of hazardous chemicals are used on a non-production basis.
Laboratory scale means work with substances in which the containers used for reactions, transfers, and other handling of substances are designed to be easily and safely manipulated by one person. “Laboratory scale” excludes those workplaces whose function is to produce commercial quantities of materials.
Laboratory-type hood means a device located in a laboratory, enclosure on five sides with a moveable sash or fixed partial enclosed on the remaining side; constructed and maintained to draw air from the laboratory and to prevent or minimize the escape of air contaminants into the laboratory; and allows chemical manipulations to be conducted in the enclosure without insertion of any portion of the employee's body other than hands and arms.
Walk-in hoods with adjustable sashes meet the above definition provided that the sashes are adjusted during use so that the airflow and the exhaust of air contaminants are not compromised and employees do not work inside the enclosure during the release of airborne hazardous chemicals.
Laboratory use of hazardous chemicals means handling or use of such chemicals in which all of the following conditions are met:
Medical consultation means a consultation which takes place between an employee and a licensed physician for the purpose of determining what medical examinations or procedures, if any, are appropriate in cases where a significant exposure to a hazardous chemical may have taken place.
Mutagen means chemicals that cause permanent changes in the amount or structure of the genetic material in a cell. Chemicals classified as mutagens in accordance with the Hazard Communication Standard (§ 1910.1200) shall be considered mutagens for purposes of this section.
Physical hazard means a chemical that is classified as posing one of the following hazardous effects: Explosive; flammable (gases, aerosols, liquids, or solids); oxidizer (liquid, solid, or gas); self reactive; pyrophoric (gas, liquid or solid); self-heating; organic peroxide; corrosive to metal; gas under pressure; in contact with water emits flammable gas; or combustible dust. The criteria for determining whether a chemical is classified as a physical hazard are in appendix B of the Hazard Communication Standard (§ 1910.1200) and § 1910.1200(c) (definitions of “combustible dust” and “pyrophoric gas”).
Protective laboratory practices and equipment means those laboratory procedures, practices and equipment accepted by laboratory health and safety experts as effective, or that the employer can show to be effective, in minimizing the potential for employee exposure to hazardous chemicals.
Reproductive toxins mean chemicals that affect the reproductive capabilities including adverse effects on sexual function and fertility in adult males and females, as well as adverse effects on the development of the offspring. Chemicals classified as reproductive toxins in accordance with the Hazard Communication Standard (§ 1910.1200) shall be considered reproductive toxins for purposes of this section.
Select carcinogen means any substance which meets one of the following criteria:
For laboratory uses of OSHA regulated substances, the employer shall assure that laboratory employees' exposures to such substances do not exceed the permissible exposure limits specified in 29 CFR part 1910, subpart Z.
The employer shall measure the employee's exposure to any substance regulated by a standard which requires monitoring if there is reason to believe that exposure levels for that substance routinely exceed the action level (or in the absence of an action level, the PEL).
If the initial monitoring prescribed by paragraph (d)(1) of this section discloses employee exposure over the action level (or in the absence of an action level, the PEL), the employer shall immediately comply with the exposure monitoring provisions of the relevant standard.
Monitoring may be terminated in accordance with the relevant standard.
The employer shall, within 15 working days after the receipt of any monitoring results, notify the employee of these results in writing either individually or by posting results in an appropriate location that is accessible to employees.
Employees shall be informed of:
The employer shall provide the following information to the physician:
Where the use of respirators is necessary to maintain exposure below permissible exposure limits, the employer shall provide, at no cost to the employee, the proper respiratory equipment. Respirators shall be selected and used in accordance with the requirements of 29 CFR 1910.134.
The information contained in the appendices is not intended, by itself, to create any additional obligations not otherwise imposed or to detract from any existing obligation.
Appendix A to § 1910.1450—National Research Council Recommendations Concerning Chemical Hygiene In Laboratories (Non-Mandatory)
To assist employers in developing an appropriate laboratory Chemical Hygiene Plan (CHP), the following non-mandatory recommendations were based on the National Research Council's (NRC) 2011 edition of “Prudent Practices in the Laboratory: Handling and Management of Chemical Hazards.” This reference, henceforth referred to as “Prudent Practices,” is available from the National Academies Press, 500 Fifth Street NW., Washington DC 20001 ( www.nap.edu ). “Prudent Practices” is cited because of its wide distribution and acceptance and because of its preparation by recognized authorities in the laboratory community through the sponsorship of the NRC. However, these recommendations do not modify any requirements of the OSHA Laboratory standard. This appendix presents pertinent recommendations from “Prudent Practices,” organized into a form convenient for quick reference during operation of a laboratory and during development and application of a CHP. For a detailed explanation and justification for each recommendation, consult “Prudent Practices.”
“Prudent Practices” deals with both general laboratory safety and many types of chemical hazards, while the Laboratory standard is concerned primarily with chemical health hazards as a result of chemical exposures. The recommendations from “Prudent Practices” have been paraphrased, combined, or otherwise reorganized in order to adapt them for this purpose. However, their sense has not been changed.
Section F contains information from the U.S. Chemical Safety Board's (CSB) Fiscal Year 2011 Annual Performance and Accountability report and Section F contains recommendations extracted from the CSB's 2011 case study, “Texas Tech University Laboratory Explosion,” available from: http://www.csb.gov/.
Culture of Safety
With the promulgation of the Occupational Safety and Health Administration (OSHA) Laboratory standard (29 CFR 1910.1450), a culture of safety consciousness, accountability, organization, and education has developed in industrial, governmental, and academic laboratories. Safety and training programs have been implemented to promote the safe handling of chemicals from ordering to disposal, and to train laboratory personnel in safe practices. Laboratory personnel must realize that the welfare and safety of each individual depends on clearly defined attitudes of teamwork and personal responsibility. Learning to participate in this culture of habitual risk assessment, experiment planning, and consideration of worst-case possibilities—for oneself and one's fellow workers—is as much part of a scientific education as learning the theoretical background of experiments or the step-by-step protocols for doing them in a professional manner. A crucial component of chemical education for all personnel is to nurture basic attitudes and habits of prudent behavior so that safety is a valued and inseparable part of all laboratory activities throughout their career.
Over the years, special techniques have been developed for handling chemicals safely. Local, state, and federal regulations hold institutions that sponsor chemical laboratories accountable for providing safe working environments. Beyond regulation, employers and scientists also hold themselves personally responsible for their own safety, the safety of their colleagues and the safety of the general public. A sound safety organization that is respected by all requires the participation and support of laboratory administrators, workers, and students. A successful health and safety program requires a daily commitment from everyone in the organization. To be most effective, safety and health must be balanced with, and incorporated into, laboratory processes. A strong safety and health culture is the result of positive workplace attitudes—from the chief executive officer to the newest hire; involvement and buy-in of all members of the workforce; mutual, meaningful, and measurable safety and health improvement goals; and policies and procedures that serve as reference tools, rather than obscure rules.
In order to perform their work in a prudent manner, laboratory personnel must consider the health, physical, and environmental hazards of the chemicals they plan to use in an experiment. However, the ability to accurately identify and assess laboratory hazards must be taught and encouraged through training and ongoing organizational support. This training must be at the core of every good health and safety program. For management to lead, personnel to assess worksite hazards, and hazards to be eliminated or controlled, everyone involved must be trained.
A. General Principles
1. Minimize All Chemical Exposures and Risks
Because few laboratory chemicals are without hazards, general precautions for handling all laboratory chemicals should be adopted. In addition to these general guidelines, specific guidelines for chemicals that are used frequently or are particularly hazardous should be adopted.
Laboratory personnel should conduct their work under conditions that minimize the risks from both known and unknown hazardous substances. Before beginning any laboratory work, the hazards and risks associated with an experiment or activity should be determined and the necessary safety precautions implemented. Every laboratory should develop facility-specific policies and procedures for the highest-risk materials and procedures used in their laboratory. To identify these, consideration should be given to past accidents, process conditions, chemicals used in large volumes, and particularly hazardous chemicals.
Perform Risk Assessments for Hazardous Chemicals and Procedures Prior to Laboratory Work:
One sample approach to risk assessment is to answer these five questions:
2. Avoid Underestimation of Risk
Even for substances of no known significant hazard, exposure should be minimized; when working with substances that present special hazards, special precautions should be taken. Reference should be made to the safety data sheet (SDS) that is provided for each chemical. Unless otherwise known, one should assume that any mixture will be more toxic than its most toxic component and that all substances of unknown toxicity are toxic.
Determine the physical and health hazards associated with chemicals before working with them. This determination may involve consulting literature references, laboratory chemical safety summaries (LCSSs), SDSs, or other reference materials. Consider how the chemicals will be processed and determine whether the changing states or forms will change the nature of the hazard. Review your plan, operating limits, chemical evaluations and detailed risk assessment with other chemists, especially those with experience with similar materials and protocols.
Before working with chemicals, know your facility's policies and procedures for how to handle an accidental spill or fire. Emergency telephone numbers should be posted in a prominent area. Know the location of all safety equipment and the nearest fire alarm and telephone.
3. Adhere to the Hierarchy of Controls
The hierarchy of controls prioritizes intervention strategies based on the premise that the best way to control a hazard is to systematically remove it from the workplace, rather than relying on employees to reduce their exposure. The types of measures that may be used to protect employees (listed from most effective to least effective) are: engineering controls, administrative controls, work practices, and PPE. Engineering controls, such as chemical hoods, physically separate the employee from the hazard. Administrative controls, such as employee scheduling, are established by management to help minimize the employees' exposure time to hazardous chemicals. Work practice controls are tasks that are performed in a designated way to minimize or eliminate hazards. Personal protective equipment and apparel are additional protection provided under special circumstances and when exposure is unavoidable.
Face and eye protection is necessary to prevent ingestion and skin absorption of hazardous chemicals. At a minimum, safety glasses, with side shields, should be used for all laboratory work. Chemical splash goggles are more appropriate than regular safety glasses to protect against hazards such as projectiles, as well as when working with glassware under reduced or elevated pressures (e.g., sealed tube reactions), when handling potentially explosive compounds (particularly during distillations), and when using glassware in high-temperature operations. Do not allow laboratory chemicals to come in contact with skin. Select gloves carefully to ensure that they are impervious to the chemicals being used and are of correct thickness to allow reasonable dexterity while also ensuring adequate barrier protection.
Lab coats and gloves should be worn when working with hazardous materials in a laboratory. Wear closed-toe shoes and long pants or other clothing that covers the legs when in a laboratory where hazardous chemicals are used. Additional protective clothing should be used when there is significant potential for skin-contact exposure to chemicals. The protective characteristics of this clothing must be matched to the hazard. Never wear gloves or laboratory coats outside the laboratory or into areas where food is stored and consumed.
4. Provide Laboratory Ventilation
The best way to prevent exposure to airborne substances is to prevent their escape into the working atmosphere by the use of hoods and other ventilation devices. To determine the best choice for laboratory ventilation using engineering controls for personal protection, employers are referred to Table 9.3 of the 2011 edition of “Prudent Practices.” Laboratory chemical hoods are the most important components used to protect laboratory personnel from exposure to hazardous chemicals.
A laboratory ventilation system should include the following characteristics and practices:
Before work begins, laboratory workers should be provided with proper training that includes how to use the ventilation equipment, how to ensure that it is functioning properly, the consequences of improper use, what to do in the event of a system failure or power outage, special considerations, and the importance of signage and postings.
5. Institute a Chemical Hygiene Program
A comprehensive chemical hygiene program is required. It should be designed to minimize exposures, injuries, illnesses and incidents. There should be a regular, continuing effort that includes program oversight, safe facilities, chemical hygiene planning, training, emergency preparedness and chemical security. The chemical hygiene program must be reviewed annually and updated as necessary whenever new processes, chemicals, or equipment is implemented. Its recommendations should be followed in all laboratories.
6. Observe the PELs and TLVs
OSHA's Permissible Exposure Limits (PELs) must not be exceeded. The American Conference of Governmental Industrial Hygienists' Threshold Limit Values (TLVs) should also not be exceeded.
B. Responsibilities
Persons responsible for chemical hygiene include, but are not limited to, the following:
1. Chemical Hygiene Officer
2. Department Chairperson or Director
3. Departmental Safety Committee reviews accident reports and makes appropriate recommendations to the department chairperson regarding proposed changes in the laboratory procedures.
4. Laboratory Supervisor or Principal Investigator has overall responsibility for chemical hygiene in the laboratory, including responsibility to:
5. Laboratory Personnel
C. The Laboratory Facility
General Laboratory Design Considerations
Wet chemical spaces and those with a higher degree of hazard should be separated from other spaces by a wall or protective barrier wherever possible. If the areas cannot be separated, then workers in lower hazard spaces may require additional protection from the hazards in connected spaces.
1. Laboratory Layout and Furnishing
2. Safety Equipment and Utilities
D. Chemical Hygiene Plan (CHP)
The OSHA Laboratory standard defines a CHP as “a written program developed and implemented by the employer which sets forth procedures, equipment, personal protective equipment and work practices that are capable of protecting employees from the health hazards presented by hazardous chemicals used in that particular workplace.” (29 CFR 1910.1450(b)). The Laboratory Standard requires a CHP: “Where hazardous chemicals as defined by this standard are used in the workplace, the employer shall develop and carry out the provisions of a written Chemical Hygiene Plan.” (29 CFR 1910.1450(e)(1)). The CHP is the foundation of the laboratory safety program and must be reviewed and updated, as needed, and at least on an annual basis to reflect changes in policies and personnel. A CHP should be facility specific and can assist in promoting a culture of safety to protect workers from exposure to hazardous materials.
1. The Laboratory's CHP must be readily available to workers and capable of protecting workers from health hazards and minimizing exposure. Include the following topics in the CHP:
It should be noted that the nature of laboratory work may necessitate addressing biological safety, radiation safety and security issues.
2. Chemical Procurement, Distribution, and Storage
Prudent chemical management includes the following processes:
Chemical Procurement:
Chemical Storage:
and label information should be followed for storage requirements.
Chemical Handling:
Chemical Inventory:
Transporting Chemicals:
Transferring Chemicals:
Shipping Chemicals: Outgoing chemical shipments must meet all applicable Department of Transportation (DOT) regulations and should be authorized and handled by the institutional shipper.
3. Waste Management
A waste management plan should be in place before work begins on any laboratory activity. The plan should utilize the following hierarchy of practices:
The best approach to minimize waste generation is by reducing the scale of operations, reducing its formation during operations, and, if possible, substituting less hazardous chemicals for a particular operation.
Only the amount of material necessary for an experiment should be purchased, and, if possible, materials should be reused.
If waste cannot be prevented or minimized, the organization should consider recycling chemicals that can be safely recovered or used as fuel.
Sink disposal may not be appropriate. Proper waste disposal methods include incineration, treatment, and land disposal. The organization's environmental health and safety (EHS) office should be consulted in determining which methods are appropriate for different types of waste.
Collection and Storage of Waste:
4. Inspection Program
Maintenance and regular inspection of laboratory equipment are essential parts of the laboratory safety program. Management should participate in the design of a laboratory inspection program to ensure that the facility is safe and healthy, workers are adequately trained, and proper procedures are being followed.
Types of inspections: The program should include an appropriate combination of routine inspections, self-audits, program audits, peer inspections, EHS inspections, and inspections by external entities.
Elements of an inspection:
5. Medical Consultation and Examination
The employer must provide all employees who work with hazardous chemicals an opportunity to receive medical attention, including any follow-up examinations that the examining physician determines to be necessary, whenever an employee develops signs or symptoms associated with a hazardous chemical to which the employee may have been exposed in the laboratory. If an employee encounters a spill, leak, explosion or other occurrence resulting in the likelihood of a hazardous exposure, the affected employee must be provided an opportunity for a medical consultation by a licensed physician. All medical examinations and consultations must be performed by or under the direct supervision of a licensed physician and must be provided without cost to the employee, without loss of pay and at a reasonable time and place. The identity of the hazardous chemical, a description of the incident, and any signs and symptoms that the employee may experience must be relayed to the physician.
6. Records
All accident, fatality, illness, injury, and medical records and exposure monitoring records must be retained by the institution in accordance with the requirements of state and federal regulations (see 29 CFR part 1904 and § 1910.1450(j)). Any exposure monitoring results must be provided to affected laboratory staff within 15 working days after receipt of the results (29 CFR 1910.1450(d)(4)).
7. Signs
Prominent signs of the following types should be posted:
8. Spills and Accidents
Before beginning an experiment, know your facility's policies and procedures for how to handle an accidental release of a hazardous substance, a spill or a fire. Emergency response planning and training are especially important when working with highly toxic compounds. Emergency telephone numbers should be posted in a prominent area. Know the location of all safety equipment and the nearest fire alarm and telephone. Know who to notify in the event of an emergency. Be prepared to provide basic emergency treatment. Keep your co-workers informed of your activities so they can respond appropriately. Safety equipment, including spill control kits, safety shields, fire safety equipment, PPE, safety showers and eyewash units, and emergency equipment should be available in well-marked highly visible locations in all chemical laboratories. The laboratory supervisor or CHO is responsible for ensuring that all personnel are aware of the locations of fire extinguishers and are trained in their use. After an extinguisher has been used, designated personnel must promptly recharge or replace it (29 CFR 1910.157(c)(4)). The laboratory supervisor or CHO is also responsible for ensuring proper training and providing supplementary equipment as needed.
Special care must be used when handling solutions of chemicals in syringes with needles. Do not recap needles, especially when they have been in contact with chemicals. Remove the needle and discard it immediately after use in the appropriate sharps containers. Blunt-tip needles are available from a number of commercial sources and should be used unless a sharp needle is required to puncture rubber septa or for subcutaneous injection.
For unattended operations, laboratory lights should be left on, and signs should be posted to identify the nature of the experiment and the hazardous substances in use. Arrangements should be made, if possible, for other workers to periodically inspect the operation. Information should be clearly posted indicating who to contact in the event of an emergency. Depending on the nature of the hazard, special rules, precautions, and alert systems may be necessary.
9. Training and Information
Personnel training at all levels within the organization, is essential. Responsibility and accountability throughout the organization are key elements in a strong safety and health program. The employer is required to provide employees with information and training to ensure that they are apprised of the hazards of chemicals present in their work area (29 CFR 1910.1450(f)). This information must be provided at the time of an employee's initial assignment to a work area where hazardous chemicals are present and prior to assignments involving new exposure situations. The frequency of refresher information and training should be determined by the employer. At a minimum, laboratory personnel should be trained on their facility's specific CHP, methods and observations that may be used to detect the presence or release of a hazardous chemical (such as monitoring conducted by the employer, continuous monitoring devices, visual appearance or odor of hazardous chemicals when being released), the physical and health hazards of chemicals in the work area and means to protect themselves from these hazards. Trained laboratory personnel must know shut-off procedures in case of an emergency. All SDSs must be made available to the employees.
E. General Procedures for Working With Chemicals
The risk of laboratory injuries can be reduced through adequate training, improved engineering, good housekeeping, safe work practice and personal behavior.
1. General Rules for Laboratory Work With Chemicals
Working Alone in the Laboratory
Working alone in a laboratory is dangerous and should be strictly avoided. There have been many tragic accidents that illustrate this danger. Accidents are unexpected by definition, which is why coworkers should always be present. Workers should coordinate schedules to avoid working alone.
Housekeeping
Housekeeping can help reduce or eliminate a number of laboratory hazards. Proper housekeeping includes appropriate labeling and storage of chemicals, safe and regular cleaning of the facility, and proper arrangement of laboratory equipment.
2. Nanoparticles and Nanomaterials
Nanoparticles and nanomaterials have different reactivities and interactions with biological systems than bulk materials, and understanding and exploiting these differences is an active area of research. However, these differences also mean that the risks and hazards associated with exposure to engineered nanomaterials are not well known. Because this is an area of ongoing research, consult trusted sources for the most up to date information available. Note that the higher reactivity of many nanoscale materials suggests that they should be treated as potential sources of ignition, accelerants, and fuel that could result in fire or explosion. Easily dispersed dry nanomaterials may pose the greatest health hazard because of the risk of inhalation. Operations involving these nanomaterials deserve more attention and more stringent controls than those where the nanomaterials are embedded in solid or suspended in liquid matrixes.
Consideration should be given to all possible routes of exposure to nanomaterials including inhalation, ingestion, injection, and dermal contact (including eye and mucous membranes). Avoid handling nanomaterials in the open air in a free-particle state. Whenever possible, handle and store dispersible nanomaterials, whether suspended in liquids or in a dry particle form, in closed (tightly-sealed) containers. Unless cutting or grinding occurs, nanomaterials that are not in a free form (encapsulated in a solid or a nanocomposite) typically will not require engineering controls. If a synthesis is being performed to create nanomaterials, it is not enough to only consider the final material in the risk assessment, but consider the hazardous properties of the precursor materials as well.
To minimize laboratory personnel exposure, conduct any work that could generate engineered nanoparticles in an enclosure that operates at a negative pressure differential compared to the laboratory personnel breathing zone. Limited data exist regarding the efficacy of PPE and ventilation systems against exposure to nanoparticles. However, until further information is available, it is prudent to follow standard chemical hygiene practices. Conduct a hazard evaluation to determine PPE appropriate for the level of hazard according to the requirements set forth in OSHA's Personal Protective Equipment standard (29 CFR 1910.132).
3. Highly Toxic and Explosive/Reactive Chemicals/Materials
The use of highly toxic and explosive/reactive chemicals and materials has been an area of growing concern. The frequency of academic laboratory incidents in the U.S. is an area of significant concern for the Chemical Safety Board (CSB). The CSB issued a case study on an explosion at Texas Tech University in Lubbock, Texas, which severely injured a graduate student handling a high-energy metal compound. Since 2001, the CSB has gathered preliminary information on 120 different university laboratory incidents that resulted in 87 evacuations, 96 injuries, and three deaths.
It is recommended that each facility keep a detailed inventory of highly toxic chemicals and explosive/reactive materials. There should be a record of the date of receipt, amount, location, and responsible individual for all acquisitions, syntheses, and disposal of these chemicals. A physical inventory should be performed annually to verify active inventory records. There should be a procedure in place to report security breaches, inventory discrepancies, losses, diversions, or suspected thefts.
Procedures for disposal of highly toxic materials should be established before any experiments begin, possibly even before the chemicals are ordered. The procedures should address methods for decontamination of any laboratory equipment that comes into contact with highly toxic chemicals. All waste should be accumulated in clearly labeled impervious containers that are stored in unbreakable secondary containment.
Highly reactive and explosive materials that may be used in the laboratory require appropriate procedures and training. An explosion can occur when a material undergoes a rapid reaction that results in a violent release of energy. Such reactions can happen spontaneously and can produce pressures, gases, and fumes that are hazardous. Some reagents pose a risk on contact with the atmosphere. It is prudent laboratory practice to use a safer alternative whenever possible.
If at all possible, substitutes for highly acute, chronic, explosive, or reactive chemicals should be considered prior to beginning work and used whenever possible.
4. Compressed Gas
Compressed gases expose laboratory personnel to both chemical and physical hazards. It is essential that these are monitored for leaks and have the proper labeling. By monitoring compressed gas inventories and disposing of or returning gases for which there is no immediate need, the laboratory can substantially reduce these risks. Leaking gas cylinders can cause serious hazards that may require an immediate evacuation of the area and activation of the emergency response system. Only appropriately trained hazmat responders may respond to stop a leaking gas cylinder under this situation.
F. Safety Recommendations—Physical Hazards
Physical hazards in the laboratory include combustible liquids, compressed gases, reactives, explosives and flammable chemicals, as well as high pressure/energy procedures, sharp objects and moving equipment. Injuries can result from bodily contact with rotating or moving objects, including mechanical equipment, parts, and devices. Personnel should not wear loose-fitting clothing, jewelry, or unrestrained long hair around machinery with moving parts.
The Chemical Safety Board has identified the following key lessons for laboratories that address both physical and other hazards:
G. Emergency Planning
In addition to laboratory safety issues, laboratory personnel should be familiar with established facility policies and procedures regarding emergency situations. Topics may include, but are not limited to:
It is prudent that laboratory personnel are also trained in how to respond to short-term, long-term and large-scale emergencies. Laboratory security can play a role in reducing the likelihood of some emergencies and assisting in preparation and response for others. Every institution, department, and individual laboratory should consider having an emergency preparedness plan. The level of detail of the plan will vary depending on the function of the group and institutional planning efforts already in place.
Emergency planning is a dynamic process. As personnel, operations, and events change, plans will need to be updated and modified. To determine the type and level of emergency planning needed, laboratory personnel need to perform a vulnerability assessment. Periodic drills to assist in training and evaluation of the emergency plan are recommended as part of the training program.
H. Emergency Procedures
Most organizations use fire alarms whenever a building needs to be evacuated—for any reason. When a fire alarm sounds in the facility, evacuate immediately after extinguishing all equipment flames. Check on and assist others who may require help evacuating.
The following safety elements should be met:
a. A written emergency action plan has been provided to workers;
b. Fire extinguishers, eyewash units, and safety showers are available and tested on a regular basis; and
c. Fire blankets, first-aid equipment, fire alarms, and telephones are available and accessible.
Workers should contact the CHO or EHS office for instructions before cleaning up a chemical spill. All SDS and label instructions should be followed, and appropriate PPE should be worn during spill cleanup.
In the event of an accident, immediately notify appropriate personnel and local emergency responders. Provide an SDS of any chemical involved to the attending physician. Complete an accident report and submit it to the appropriate office or individual within 24 hours.
New workers should attend safety training before they begin any activities. Additional training should be provided when they advance in their duties or are required to perform a task for the first time. Training documents should be recorded and maintained. Training should include hands-on instruction of how to use safety equipment appropriately.
Practice building evacuations, including the use of alternate routes. Practice shelter-in-place, including plans for extended stays. Walk the fastest route from your work area to the nearest fire alarm, emergency eye wash and emergency shower. Learn how each is activated. In the excitement of an actual emergency, people rely on what they learned from drills, practice and training.
All laboratories should have long-term contingency plans in place (e.g., for pandemics). Scheduling, workload, utilities and alternate work sites may need to be considered.
I. Laboratory Security
Laboratory security has evolved in the past decade, reducing the likelihood of some emergencies and assisting in preparation and response for others. Most security measures are based on the laboratory's vulnerability. Risks to laboratory security include, but are not limited to:
Security systems in the laboratory are used to detect and respond to a security breach, or a potential security breach, as well as to delay criminal activity by imposing multiple layered barriers of increasing stringency. A good laboratory security system will increase overall safety for laboratory personnel and the public, improve emergency preparedness by assisting with preplanning, and lower the organization's liability by incorporating more rigorous planning, staffing, training, and command systems and implementing emergency communications protocols, drills, background checks, card access systems, video surveillance, and other measures. The security plan should clearly delineate response to security issues, including the coordination of institution and laboratory personnel with both internal and external responders.
Appendix B to § 1910.1450—References (Non-Mandatory)
The following references are provided to assist the employer in the development of a Chemical Hygiene Plan. The materials listed below are offered as non-mandatory guidance. References listed here do not imply specific endorsement of a book, opinion, technique, policy or a specific solution for a safety or health problem. Other references not listed here may better meet the needs of a specific laboratory.
1. American Chemical Society, Safety in Academic Chemistry Laboratories, 4th edition, 1985.
2. Fawcett, H.H. and W. S. Wood, Safety and Accident Prevention in Chemical Operations, 2nd edition, Wiley-Interscience, New York, 1982.
3. Flury, Patricia A., Environmental Health and Safety in the Hospital Laboratory, Charles C. Thomas Publisher, Springfield IL, 1978.
4. Green, Michael E. and Turk, Amos, Safety in Working with Chemicals, Macmillan Publishing Co., NY, 1978.
5. Kaufman, James A., Laboratory Safety Guidelines, Dow Chemical Co., Box 1713, Midland, MI 48640, 1977.
6. National Institutes of Health, NIH Guidelines for the Laboratory use of Chemical Carcinogens, NIH Pub. No. 81-2385, GPO, Washington, DC 20402, 1981.
7. National Research Council, Prudent Practices for Disposal of Chemicals from Laboratories, National Academy Press, Washington, DC, 1983.
8. National Research Council, Prudent Practices for Handling Hazardous Chemicals in Laboratories, National Academy Press, Washington, DC, 1981.
9. Renfrew, Malcolm, Ed., Safety in the Chemical Laboratory, Vol. IV, J. Chem. Ed., American Chemical Society, Easlon, PA, 1981.
10. Steere, Norman V., Ed., Safety in the Chemical Laboratory, J. Chem. Ed. American Chemical Society, Easlon, PA, 18042, Vol. I, 1967, Vol. II, 1971, Vol. III 1974.
11. Steere, Norman V., Handbook of Laboratory Safety, the Chemical Rubber Company Cleveland, OH, 1971.
12. Young, Jay A., Ed., Improving Safety in the Chemical Laboratory, John Wiley & Sons, Inc. New York, 1987.
1. American Conference of Governmental Industrial Hygienists, Threshold Limit Values for Chemical Substances and Physical Agents in the Workroom Environment with Intended Changes, 6500 Glenway Avenue, Bldg. D-7 Cincinnati, OH 45211-4438 (latest edition).
2. Annual Report on Carcinogens, National Toxicology Program U.S. Department of Health and Human Services, Public Health Service, U.S. Government Printing Office, Washington, DC, (latest edition).
3. Best Company, Best Safety Directory, Vols. I and II, Oldwick, N.J., 1981.
4. Bretherick, L., Handbook of Reactive Chemical Hazards, 2nd edition, Butterworths, London, 1979.
5. Bretherick, L., Hazards in the Chemical Laboratory, 3rd edition, Royal Society of Chemistry, London, 1986.
6. Code of Federal Regulations, 29 CFR part 1910 subpart Z. U.S. Govt. Printing Office, Washington, DC 20402 (latest edition).
7. IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man, World Health Organization Publications Center, 49 Sheridan Avenue, Albany, New York 12210 (latest editions).
8. NIOSH/OSHA Pocket Guide to Chemical Hazards. NIOSH Pub. No. 85-114, U.S. Government Printing Office, Washington, DC, 1985 (or latest edition).
9. Occupational Health Guidelines, NIOSH/OSHA NIOSH Pub. No. 81-123 U.S. Government Printing Office, Washington, DC, 1981.
10. Patty, F.A., Industrial Hygiene and Toxicology, John Wiley & Sons, Inc., New York, NY (Five Volumes).
11. Registry of Toxic Effects of Chemical Substances, U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, Revised Annually, for sale from Superintendent of Documents U.S. Govt. Printing Office, Washington, DC 20402.
12. The Merck Index: An Encyclopedia of Chemicals and Drugs. Merck and Company Inc. Rahway, N.J., 1976 (or latest edition).
13. Sax, N.I. Dangerous Properties of Industrial Materials, 5th edition, Van Nostrand Reinhold, NY., 1979.
14. Sittig, Marshall, Handbook of Toxic and Hazardous Chemicals, Noyes Publications, Park Ridge, NJ, 1981.
1. American Conference of Governmental Industrial Hygienists Industrial Ventilation (latest edition), 6500 Glenway Avenue, Bldg. D-7, Cincinnati, Ohio 45211-4438.
2. American National Standards Institute, Inc. American National Standards Fundamentals Governing the Design and Operation of Local Exhaust Systems ANSI Z 9.2-1979 American National Standards Institute, N.Y. 1979.
3. Imad, A.P. and Watson, C.L. Ventilation Index: An Easy Way to Decide about Hazardous Liquids, Professional Safety pp 15-18, April 1980.
4. National Fire Protection Association, Fire Protection for Laboratories Using Chemicals NFPA-45, 1982.
Safety Standard for Laboratories in Health Related Institutions, NFPA, 56c, 1980.
Fire Protection Guide on Hazardous Materials, 7th edition, 1978.
National Fire Protection Association, Batterymarch Park, Quincy, MA 02269.
5. Scientific Apparatus Makers Association (SAMA), Standard for Laboratory Fume Hoods, SAMA LF7-1980, 1101 16th Street, NW., Washington, DC 20036.
1. American National Standards Institute (ANSI), 1430 Broadway, New York, NY 10018.
2. American Society for Testing and Materials (ASTM), 1916 Race Street, Philadelphia, PA 19103.
[55 FR 3327, Jan. 31, 1990; 55 FR 7967, Mar. 6, 1990; 55 FR 12111, Mar. 30, 1990; 57 FR 29204, July 1, 1992; 61 FR 5508, Feb. 13, 1996; 71 FR 16674, Apr. 3, 2006; 76 FR 33609, June 8, 2011; 77 FR 17887, Mar. 26, 2012; 78 FR 4325, Jan. 22, 2013]
The following sections or paragraphs each contain a collection of information requirement which has been approved by the Office of Management and Budget under the control number listed.
| 29 CFR citation | OMB control No. |
|---|---|
| 1926.33 | 1218-0065 |
| 1926.50 | 1218-0093 |
| 1926.52 | 1218-0048 |
| 1926.53 | 1218-0103 |
| 1926.59 | 1218-0072 |
| 1926.60 | 1218-0183 |
| 1926.62 | 1218-0189 |
| 1926.64 | 1218-0200 |
| 1926.65 | 1218-0202 |
| 1926.103 | 1218-0099 |
| 1926.200 | 1218-0132 |
| 1926.250 | 1218-0093 |
| 1926.251 | 1218-0233 |
| 1926.403 | 1218-0130 |
| 1926.404 | 1218-0130 |
| 1926.405 | 1218-0130 |
| 1926.407 | 1218-0130 |
| 1926.408 | 1218-0130 |
| 1926.453(a)(2) | 1218-0216 |
| 1926.502 | 1218-0197 |
| 1926.503 | 1218-0197 |
| 1926.550(a)(1) | 1218-0115 |
| 1926.550(a)(2) | 1218-0115 |
| 1926.550(a)(4) | 1218-0115 |
| 1926.550(a)(6) | 1218-0113 |
| 1926.550(a)(11) | 1218-0054 |
| 1926.550(a)(16) | 1218-0115 |
| 1926.550(b)(2) | 1218-0232 |
| 1926.550(g) | 1218-0151 |
| 1926.552 | 1218-0231 |
| 1926.652 | 1218-0137 |
| 1926.703 | 1218-0095 |
| 1926.800 | 1218-0067 |
| 1926.803 | 1218-0067 |
| 1926.900 | 1218-0217 |
| 1926.903 | 1218-0227 |
| 1926.1080 | 1218-0069 |
| 1926.1081 | 1218-0069 |
| 1926.1083 | 1218-0069 |
| 1926.1090 | 1218-0069 |
| 1926.1091 | 1218-0069 |
| 1926.1101 | 1218-0134 |
| 1926.1103 | 1218-0085 |
| 1926.1104 | 1218-0084 |
| 1926.1106 | 1218-0086 |
| 1926.1107 | 1218-0083 |
| 1926.1108 | 1218-0087 |
| 1926.1109 | 1218-0089 |
| 1926.1110 | 1218-0082 |
| 1926.1111 | 1218-0090 |
| 1926.1112 | 1218-0080 |
| 1926.1113 | 1218-0079 |
| 1926.1114 | 1218-0088 |
| 1926.1115 | 1218-0044 |
| 1926.1116 | 1218-0081 |
| 1926.1117 | 1218-0010 |
| 1926.1118 | 1218-0104 |
| 1926.1124 | 1218-0267 |
| 1926.1126 | 1218-0252 |
| 1926.1127 | 1218-0186 |
| 1926.1128 | 1218-0129 |
| 1926.1129 | 1218-0128 |
| 1926.1144 | 1218-0101 |
| 1926.1145 | 1218-0126 |
| 1926.1147 | 1218-0108 |
| 1926.1148 | 1218-0145 |
| 1926.1153 | 1218-0266 |
| 1926.1203 | 1218-0258 |
| 1926.1204 | 1218-0258 |
| 1926.1205 | 1218-0258 |
| 1926.1206 | 1218-0258 |
| 1926.1207 | 1218-0258 |
| 1926.1208 | 1218-0258 |
| 1926.1209 | 1218-0258 |
| 1926.1210 | 1218-0258 |
| 1926.1211 | 1218-0258 |
| 1926.1212 | 1218-0258 |
| 1926.1213 | 1218-0258 |
| 1926.1402 | 1218-0261 |
| 1926.1403 | 1218-0261 |
| 1926.1404 | 1218-0261 |
| 1926.1406 | 1218-0261 |
| 1926.1407 | 1218-0261 |
| 1926.1408 | 1218-0261 |
| 1926.1409 | 1218-0261 |
| 1926.1410 | 1218-0261 |
| 1926.1411 | 1218-0261 |
| 1926.1412 | 1218-0261 |
| 1926.1413 | 1218-0261 |
| 1926.1414 | 1218-0261 |
| 1926.1417 | 1218-0261 |
| 1926.1423 | 1218-0261 |
| 1926.1424 | 1218-0261 |
| 1926.1427 | 1218-0270 |
| 1926.1428 | 1218-0261 |
| 1926.1431 | 1218-0261 |
| 1926.1433 | 1218-0261 |
| 1926.1434 | 1218-0261 |
| 1926.1435 | 1218-0261 |
| 1926.1436 | 1218-0261 |
| 1926.1437 | 1218-0261 |
| 1926.1441 | 1218-0261 |
[61 FR 5509, Feb. 13, 1996, as amended at 63 FR 3814, Jan. 27, 1998; 63 FR 13340, Mar. 19, 1998; 63 FR 17094, Apr. 8, 1998; 64 FR 18810, Apr. 16, 1999; 71 FR 38086, July 5, 2006; 75 FR 68430, Nov. 8, 2010; 81 FR 48710, July 26, 2016; 81 FR 53268, Aug. 12, 2016; 83 FR 9703, Mar. 7, 2018; 84 FR 34785, July 19, 2019]
Government, and organizations which are not agencies of the U.S. Government which are incorporated by reference in this part, have the same force and effect as other standards in this part. Only the mandatory provisions ( i.e., provisions containing the word “shall” or other mandatory language) of standards incorporated by reference are adopted as standards under the Occupational Safety and Health Act.
A10.3-1970, Safety Requirements for Explosive-Actuated Fastening Tools, IBR approved for § 1926.302(e).
A10.4-1963, Safety Requirements for Workmen's Hoists, IBR approved for § 1926.552(c).
A10.5-1969, Safety Requirements for Material Hoists, IBR approved for § 1926.552(b).
A11.1-1965 (R1970), Practice for Industrial Lighting, IBR approved for § 1926.56(b).
A17.1-1965, Elevators, Dumbwaiters, Escalators, and Moving Walks, IBR approved for § 1926.552(d).
A17.1a-1967, Elevators, Dumbwaiters, Escalators, and Moving Walks Supplement, IBR approved for § 1926.552(d).
A17.1b-1968, Elevators, Dumbwaiters, Escalators, and Moving Walks Supplement, IBR approved for § 1926.552(d).
A17.1c-1969, Elevators, Dumbwaiters, Escalators, and Moving Walks Supplement, IBR approved for § 1926.552(d).
A17.1d-1970, Elevators, Dumbwaiters, Escalators, and Moving Walks Supplement, IBR approved for § 1926.552(d).
A17.2-1960, Practice for the Inspection of Elevators (Inspector's Manual), IBR approved for § 1926.552(d).
A17.2a-1965, Practice for the Inspection of Elevators (Inspector's Manual) Supplement, IBR approved for § 1926.552(d).
A17.2b-1967, Practice for the Inspection of Elevators (Inspector's Manual) Supplement, IBR approved for § 1926.552(d).
A92.2-1969, Vehicle Mounted Elevating and Rotating Work Platforms, IBR approved for §§ 1926.453(a) and 1926.453(b).
B7.1-1970, Safety Code for the Use, Care, and Protection of Abrasive Wheels, IBR approved for §§ 1926.57(g), 1926.303(b), 1926.303(c), and 1926.303(d).
B20.1-1957, Safety Code for Conveyors, Cableways, and Related Equipment, IBR approved for § 1926.555(a).
B56.1-1969, Safety Standards for Powered Industrial Trucks, IBR approved for § 1926.602(c).
O1.1-1961, Safety Code for Woodworking Machinery, IBR approved for § 1926.304(f).
Z35.1-1968, Specifications for Accident Prevention Signs; IBR approved for § 1926.200(b), (c), and 1 (i). Copies available for purchase from the IHS Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 1-877-413-5184; Web site: www.global.ihs.com.
Z35.2-1968, Specifications for Accident Prevention Tags, IBR approved for § 1926.200(i).
Z49.1-1967, Safety in Welding and Cutting, IBR approved for § 1926.350(j).
Z53.1-1967 (also referred to as ANSI Z53.1-1967), Safety Color Code for Marking Physical Hazards, ANSI approved October 9, 1967; IBR approved for § 1926.200(c). Copies available for purchase from the IHS Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 1-877-413-5184; Web site: www.global.ihs.com.
Z535.1-2006 (R2011), Safety Colors, reaffirmed July 19, 2011; IBR approved for § 1926.200(c). Copies available for purchase from the:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 877-413-5184; Web site: www.global.ihs.com; or
Z535.2-2011, Environmental and Facility Safety Signs, published September 15, 2011; IBR approved for § 1926.200(b), (c), and (i). Copies available for purchase from the:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 877-413-5184; Web site: www.global.ihs.com; or
Z535.5-2011, Safety Tags and Barricade Tapes (for Temporary Hazards), published September 15, 2011, including Errata, November 14, 2011; IBR approved for § 1926.200(h) and (i). Copies available for purchase from the:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: 877-413-5184; Web site: www.global.ihs.com; or
Z87.1-2010, Occupational and Educational Personal Eye and Face Protection Devices, Approved April 3, 2010; IBR approved for § 1926.102(b). Copies are available for purchase from:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: (877) 413-5184; Web site: http://global.ihs.com; or
Z87.1-2003, Occupational and Educational Personal Eye and Face Protection Devices, Approved June 19, 2003; IBR approved for § 1926.102(b). Copies available for purchase from the:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: (877) 413-5184; Web site: http://global.ihs.com; or
Z87.1-1989 (R-1998), Practice for Occupational and Educational Eye and Face Protection, Reaffirmation approved January 4, 1999; IBR approved for § 1926.102(b). Copies are available for purchase from:
Standards Store, 15 Inverness Way East, Englewood, CO 80112; telephone: (877) 413-5184; Web site: http://global.ihs.com; or
B15.1-1953 (R1958), Safety Code for Mechanical Power-Transmission Apparatus, revised 1958, IBR approved for § 1926.300(b)(2).
B30.5-1968, Crawler, Locomotive, and Truck Cranes, approved Dec. 16, 1968, IBR approved for § 1926.1433(a).
Methods and Definitions for Mechanical Testing and Steel Products, IBR approved for § 1926.1001(f).
Standard Method of Test for Flash Point by the Tag Closed Tester, IBR approved for § 1926.155(i).
Standard Method of Test for Flash Point by the Pensky Martens Closed Tester, IBR approved for § 1926.155(i).
B30.2-2005, Overhead and Gantry Cranes (Top Running Bridge, Single or Multiple Girder, Top Running Trolley Hoist), issued Dec. 30, 2005 (“ASME B30.2-2005”), IBR approved for § 1926.1438(b).
B30.5-2004, Mobile and Locomotive Cranes, issued Sept. 27, 2004 (“ASME B30.5-2004”), IBR approved for §§ 1926.1414(b); 1926.1414(e); 1926.1433(b).
B30.7-2001, Base-Mounted Drum Hoists, issued Jan. 21, 2002 (“ASME B30.7-2001”), IBR approved for § 1926.1436(e).
B30.14-2004, Side Boom Tractors, issued Sept. 20, 2004 (“ASME B30.14-2004”), IBR approved for § 1926.1440(c).
Boiler and Pressure Vessel Code, Section VIII, 1968, IBR approved for §§ 1926.152(i), 1926.306(a), and 1926.603(a).
Power Boilers, Section I, 1968, IBR approved for § 1926.603(a).
R313.1-1971, Soil Cone Penetrometer, reaffirmed 1975, IBR approved for § 1926.1002(e).
D1.1/D1.1M:2002, Structural Welding Code—Steel, 18th ed., ANSI approved Aug. 31, 2001 (“AWS D1.1/D1.1M:2002”), IBR approved for § 1926.1436(c).
D14.3-94, Specification for Welding Earthmoving and Construction Equipment, ANSI approved Jun. 11, 1993 (“ANSI/AWS D14.3-94”), IBR approved for § 1926.1436(c).
13000:2004, Cranes—Mobile Cranes, published Jan. 4, 2006 (“BS EN 13000:2004”), IBR approved for § 1926.1433(c).
14439:2006, Cranes—Safety—Tower Cranes, published Jan. 31, 2007 (“BS EN 14439:2006”), IBR approved for § 1926.1433(c).
1971, IBR approved for § 1926.1000(f).
Federal Specification Plating Cadmium (Electrodeposited), IBR approved for § 1926.104(e).
No. 2, American Table of Distances for Storage of Explosives, Jun. 5, 1964, IBR approved for § 1926.914(a).
No. 20, Radio Frequency Energy—A Potential Hazard in the Use of Electric Blasting Caps, Mar. 1968, IBR approved for § 1926.900(k).
3471:2008(E), Earth-moving machinery—Roll-over protective structures—Laboratory tests and performance requirements, Fourth Edition, Aug. 8, 2008 (“ISO 3471:2008”), IBR approved for §§ 1926.1001(c) and 1926.1002(c).
5700:2013(E), Tractors for agriculture and forestry—Roll-over protective structures—Static test method and acceptance conditions, Fifth Edition, May 1, 2013 (“ISO 5700:2013”), IBR approved for § 1926.1002(c).
27850:2013(E), Tractors for agriculture and forestry—Falling object protective structures—Test procedures and performance requirements, First Edition, May.01, 2013 (“ISO 27850:2013”), IBR approved for § 1926.1003(c).
11660-1:2008(E), Cranes—Access, guards and restraints—Part 1: General, 2d ed., Feb. 15, 2008 (“ISO 11660-1:2008(E)”), IBR approved for § 1926.1423(c).
11660-2:1994(E), Cranes—Access, guards and restraints—Part 2: Mobile cranes, 1994 (“ISO 11660-2:1994(E)”), IBR approved for § 1926.1423(c).
11660-3:2008(E), Cranes—Access, guards and restraints—Part 3: Tower cranes, 2d ed., Feb. 15, 2008 (“ISO 11660-3:2008(E)”), IBR approved for § 1926.1423(c).
Maintenance and Use of Portable Fire Extinguishers, IBR approved for § 1926.150(c).
Standard for the Installation of Sprinkler Systems, IBR approved for § 1926.152(d).
The Flammable and Combustible Liquids Code, IBR approved for § 1926.152(c).
Standard for Fire Doors and Windows, Class E or F Openings, IBR approved for § 1926.152(b).
Standard Methods of Fire Test of Building Construction and Material, IBR approved for §§ 1926.152(b) and 1926.155(f).
Standard for Tank Vehicles for Flammable and Combustible Liquids, IBR approved for § 1926.152(g).
No. 1, Mobile Crane and Excavator Standards, 1968, IBR approved for § 1926.602(b).
No. 2, Mobile Hydraulic Crane Standards, 1968 (“PCSA Std. No. 2 (1968)”), IBR approved for §§ 1926.602(b) and 1926.1433(a).
No. 3, Mobile Hydraulic Excavator Standards, 1969, IBR approved for § 1926.602(b).
Handbook, IBR approved for § 1926.602(b).
Trucks and Wagons, IBR approved for § 1926.602(a).
Protective Frame with Overhead Protection-Test Procedures and Performance Requirements, approved July 1970, IBR approved for § 1926.1003(b).
Protective Enclosures-Test Procedures and Performance Requirements, approved July 1970, IBR approved for § 1926.1002(b).
May 2003), Access Systems for Off-Road Machines, reaffirmed May 2003 (“SAE J185 (May 1993)”), IBR approved for § 1926.1423(c).
Self-Propelled Graders, IBR approved for § 1926.602(a).
Front End Loaders and Dozers, IBR approved for § 1926.602(a).
J319b-1971, Self-Propelled Scrapers, IBR approved for § 1926.602(a).
J320a, Minimum Performance Criteria for Roll-Over Protective Structure for Rubber-Tired, Self-Propelled Scrapers, revised July 1969 (editorial change July 1970), IBR approved for § 1926.1001(b).
J321a-1970, Fenders for Pneumatic-Tired Earthmoving Haulage Equipment, IBR approved for § 1926.602(a).
J333a-1970, Operator Protection for Agricultural and Light Industrial Tractors, IBR approved for § 1926.602(a).
J334a, Protective Frame Test Procedures and Performance Requirements, revised July 1970, IBR approved for § 1926.1002(b).
Seat Belts for Construction Equipment, IBR approved for § 1926.602(a).
Minimum Performance Criteria for Roll-Over Protective Structure for Rubber-Tired Front End Loaders and Rubber-Tired Dozers, approved July 1969 (editorial change July 1970), IBR approved for § 1926.1001(b).
Minimum Performance Criteria for Roll-Over Protective Structure for Crawler Tractors and Crawler-Type Loaders, approved July 1969 (editorial change July 1970), IBR approved for § 1926.1001(b).
Minimum Performance Criteria for Roll-Over Protective Structure for Motor Graders, approved July 1969 (editorial change July 1970), IBR approved for § 1926.1001(b).
Critical Zone Characteristics and Dimensions for Operators of Construction and Industrial Machinery, approved July 1969, IBR approved for § 1926.1001(b).
Jun. 2003), Lattice Boom Cranes—Method of Test, revised Jun. 2003 (“SAE J987 (Jun. 2003)”), IBR approved for § 1926.1433(c).
Nov. 1993), Cantilevered Boom Crane Structures—Method of Test, revised Nov. 1993 (“SAE J1063 (Nov. 1993)”), IBR approved for § 1926.1433(c).
1967, IBR approved for § 1926.1000(f).
[75 FR 48130, Aug. 9, 2010, as amended at 77 FR 37600, June 22, 2012; 78 FR 35566, June 13, 2013; 78 FR 66641, Nov. 6, 2013; 79 FR 20692, Apr. 11, 2014; 81 FR 16092, Mar. 25, 2016; 84 FR 21574, May 14, 2019]
Reorganization Plan No. 14 of 1950 relates to the prescribing by the Secretary of Labor of “appropriate standards, regulations, and procedures” with respect to the enforcement of labor standards under Federal and federally assisted contracts which are subject to various statutes subject to the Plan. The rules of the Secretary of Labor implementing the Plan are published in part 5 of this title. Briefly, the statutes subject to the Plan include the Davis-Bacon Act, including its extension to Federal-aid highway legislation subject to 23 U.S.C. 113, and other statutes subject to the Plan by its original terms, statutes by which the Plan is expressly applied, such as the Contract Work Hours Standards Act by virtue of section 104(d) thereof.
14 of 1950 are cited and briefly described in the remaining paragraphs of this section. These descriptions are general in nature and not intended to convey the full scope of the work to be performed under each statute. The individual statutes should be resorted to for a more detailed scope of the work.
The provisions codified in 23 U.S.C. 113 apply to the initial construction, reconstruction, or improvement work performed by contractors or subcontractors on highway projects on the Federal-aid systems, the primary and secondary, as well as their extensions in urban areas, and the Interstate System, authorized under the highway laws providing for the expenditure of Federal funds upon the Federal-aid system. As cited in 41 Op. A.G. 488, 496, the Attorney General ruled that the Federal-Aid Highway Acts are subject to Reorganization Plan No. 14 of 1950.
1713, 1715a, 1715e, 1715k, 1715l(d)(3) and (4), 1715v, 1715w, 1715x, 1743, 1747, 1748, 1748h-2, 1750g, 1715l(h)(1), 1715z(j)(1), 1715z-1, 1715y(d), Subchapter 1x-A and 1x-B, 1715z-7). This act covers construction which is financed with assistance by the Federal Government through programs of loan and mortgage insurance for the following purposes:
1114(b)). The act provides grant-in-aid funds for airport construction limited to general site preparation runways, taxiways, aprons, lighting appurtenant thereto, and fire, rescue, and maintenance buildings. The act excludes construction intended for use as a public parking facility for passenger automobiles and the cost of construction of any part of an airport building except such of those buildings or parts of buildings to house facilities or activities directly related to the safety of persons at the airport.
1459). Construction contracts awarded by local authorities financed with the assistance of loans and grants from the Federal Government. The construction programs are for slum clearance and urban renewal which includes rehabilitation grants, neighborhood development programs, neighborhood renewal plans, community renewal, demolition projects, and assistance for blighted areas. See the Housing Act of 1964, paragraph (b)(21) of this section, concerning financial assistance for low-rent housing for domestic farm labor.
1416). This statute covers the construction of low-rent public housing and slum clearance projects awarded by local authorities. These projects are financed with the assistance of loans and grants from the Federal Government. The slum clearance is the demolition and removal of buildings from any slum area to be used for a low-rent housing project.
App. 2281). This act provides for Federal assistance to the several States and their political subdivisions in the field of civil defense which includes procurement, construction, leasing, or renovating of materials and facilities.
15.1, 75 Stat. 714). This joint resolution creates, by intergovernmental compact between the United States, Delaware, New Jersey, New York, and Pennsylvania, a regional agency for planning, conservation, utilization, development, management and control of the water and related sources of the Delaware River.
332a(c)). This act provides Federal grants to a university, college, or other appropriate public or nonprofit private agency or institution for part or all of the cost of constructing a facility for research or for research and related purposes. Research and related purposes means research, research training, surveys, or demonstrations in the field of education, or the dissemination of information derived therefrom, or all of such activities, including (but without limitation) experimental schools, except that such term does not include research, research training, surveys, or demonstrations in the field of sectarian instruction or the dissemination of information derived therefrom. Construction includes new buildings, and the acquisition, expansion, remodeling, replacement, and alteration of existing buildings and the equipping of new buildings and existing buildings.
295(a)(2)(D), 2662(5), 2675(a)(5)). This act authorizes Federal financial assistance in the construction of centers for research on mental retardation and related aspects of human development, of university-affiliated facilities for the mentally retarded and of facilities for the mentally retarded.
2685(a)(5)). This act authorizes Federal grants for the construction of public and other nonprofit community mental health centers.
753). This act authorizes the grant or loan of Federal funds to assist public and other nonprofit institutions of higher education in financing the construction, rehabilitation, or improvement of academic and related facilities in undergraduate and graduate schools.
35f). This act provides for Federal grants to the various States for construction of area vocational education school facilities.
355e(a)(4)). This act provides for Federal assistance to the various States for the construction of public libraries.
1609). This act provides for grants and loans to assist States and local public bodies and agencies thereof in financing the acquisition, construction, reconstruction, and improvement of facilities and equipment for use, by operation or lease or otherwise, in mass transportation service in urban areas and in coordinating such service with highway and other transportation in such areas.
2947). This act covers construction which is financed with assistance of the Federal Government for the following purposes:
1486(f); 42 U.S.C. 1452b(e)). Provides financial assistance for low-rent housing for domestic farm labor. The Act further provides for loans, through public or private agencies, where feasible, to owners or tenants of property in urban renewal areas to finance rehabilitation required to conform the property to applicable code requirements or carry out the objectives of the urban renewal plan for the area.
296a(b)(5)). This act provides for grants to assist in the construction of new facilities for collegiate, associate degree, and diploma schools of nursing, or replacement or rehabilitation of existing facilities of such schools.
App. 402). Authorizes Federal assistance in the construction of an Appalachian development highway system; construction of multicounty demonstration health facilities, hospitals, regional health, diagnostic and treatment centers, and other facilities for health; seal and fill voids in abandoned mines and to rehabilitate strip mine areas; construction of school facilities for vocational education; and to assist in construction of sewage treatment works.
1701(q)(c)(3)). This act authorizes loans to nonprofit corporations to be used for the construction of housing and related facilities for elderly families. Also, the provisions of the act provide for rehabilitation, alteration, conversion or improvement of existing structures which are otherwise inadequate for proposed dwellings used by such families.
1636(b)). This act provides for financial assistance for construction activities in connection with research and development of different forms of high-speed ground transportation and demonstration projects relating to intercity rail passenger service.
41a(b)(4)). This act authorizes grants to assist in meeting the costs of construction of public or other nonprofit workshops and rehabilitation facilities.
280b-3(b)(3)). This act provides for grants to public or private non-profit agencies or institutions for the cost of construction of medical library facilities.
5035(a)(8)). The construction industry health and safety standards do not apply to this act since it is not subject to Reorganization Plan No. 14 of 1950.
682(b)(4)). This act provides for Federal assistance to the National Capital Transportation Agency for construction of a rail rapid transit system and related facilities for the Nation's Capital.
82). The program under this legislation has expired.
1715c) and the Housing Act of 1937 (42 U.S.C. 1416). See these acts for coverage.
1857j-3). This act provides for Federal assistance to public or nonprofit agencies, institutions, and organizations and to individuals, and contracts with public or private agencies, institutions, or persons for construction of research and development facilities and demonstration plants relating to the application of preventing or controlling discharges into the air of various types of pollutants.
42a(c)(3)). This act authorizes Federal assistance to any public or nonprofit private agency or organization for the construction of a center for vocational rehabilitation of handicapped individuals who are both deaf and blind which shall be known as the National Center for Deaf-Blind Youths and Adults. Construction includes new buildings and expansion, remodeling, alteration and renovation of existing buildings, and initial equipment of such new, newly acquired, expanded, remodeled, altered, or renovated buildings.
1246). This act provides for grants to States for the construction of area vocational education school facilities. The act further provides grants to public educational agencies, organizations, or institutions for construction of residential schools to provide vocational education for the purpose of demonstrating the feasibility and desirability of such schools. The act still further provides grants to State boards, to colleges and universities, to public educational agencies, organizations or institutions to reduce the cost of borrowing funds for the construction of residential schools and dormitories.
410(d)(2)). This Act provides for construction, modification, alteration, repair, and other improvements of postal facilities located in leased buildings.
L. 91-258, section 52(b)(7)). This Act provides for Federal financial assistance to States and localities for the construction, improvement, or repair of public airports.
This Act provides for federal financial assistance to institutions of higher learning for the construction of a National Center on Educational Media and Materials for the Handicapped. The program under this statute expires on July 1, 1971. Public Law 91-230, section 662(1).
12326, 1404(a)). This Act provides for financial assistance to States for construction, expansion, remodeling, or alteration of facilities for the education of handicapped children at the preschool, elementary school, and secondary school levels.
L. 91-609, section 707(b)). This Act provides for grants to States and local public agencies to help finance the development of open-space or other land in urban areas for open-space uses. This Act becomes effective on July 1, 1971.
L. 91-518, section 405(d)). This statute provides that the National Railroad Passenger Corporation may construct physical facilities necessary to intercity rail passenger operations within the basic national rail passenger system designated by the Secretary of Transportation.
In the course of the legislative development of section 107, it was recognized that section 107 would not apply to housing construction for which insurance was issued by the Federal Housing Authority and Veterans' Administration for individual home ownership. Concerning construction under the National Housing Act, Reorganization Plan No. 14 of 1950 applies to construction which is subject to the minimum wage requirements of section 212(a) thereof (12 U.S.C. 1715c).
Standards in this part requiring the employer to provide personal protective equipment (PPE), including respirators and other types of PPE, because of hazards to employees impose a separate compliance duty with respect to each employee covered by the requirement. The employer must provide PPE to each employee required to use the PPE, and each failure to provide PPE to an employee may be considered a separate violation.
Standards in this part requiring training on hazards and related matters, such as standards requiring that employees receive training or that the employer train employees, provide training to employees, or institute or implement a training program, impose a separate compliance duty with respect to each employee covered by the requirement. The employer must train each affected employee in the manner required by the standard, and each failure to train an employee may be considered a separate violation.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35078, June 30, 1993; 73 FR 75588, Dec. 12, 2008; 85 FR 8735, Feb. 18, 2020; 85 FR 8735, Feb. 18, 2020]
The Secretary shall, pursuant to section 107(f) of the Act, establish and supervise programs for the education and training of employers and employees in the recognition, avoidance and prevention of unsafe conditions in employments covered by the act.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 80 FR 25518, May 4, 2015]
First aid services and provisions for medical care shall be made available by the employer for every employee covered by these regulations. Regulations prescribing specific requirements for first aid, medical attention, and emergency facilities are contained in subpart D of this part.
The employer shall be responsible for the development and maintenance of an effective fire protection and prevention program at the job site throughout all phases of the construction, repair, alteration, or demolition work. The employer shall ensure the availability of the fire protection and suppression equipment required by subpart F of this part.
Construction areas, aisles, stairs, ramps, runways, corridors, offices, shops, and storage areas where work is in progress shall be lighted with either natural or artificial illumination. The minimum illumination requirements for work areas are contained in subpart D of this part.
Health and sanitation requirements for drinking water are contained in subpart D of this part.
Current and valid certification by an insurance company or regulatory authority shall be deemed as acceptable evidence of safe installation, inspection, and testing of pressure vessels provided by the employer.
Boilers provided by the employer shall be deemed to be in compliance with the requirements of this part when evidence of current and valid certification by an insurance company or regulatory authority attesting to the safe installation, inspection, and testing is presented.
Regulations prescribing specific requirements for other types of pressure vessels and similar equipment are contained in subparts F and O of this part.
Shipbuilding, ship repairing, alterations, and maintenance performed on ships under Government contract, except naval ship construction, is work subject to the Act.
For the purpose of work carried out under this section, the safety and health regulations in part 1915 of this title, Shipyard Employment, shall apply.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 61 FR 9249, Mar. 7, 1996]
The following definitions shall apply in the application of the regulations in this part:
means American National Standards Institute.
For purposes of this section, Construction work means work for construction, alteration, and/or repair, including painting and decorating.
means Society of Automotive Engineers.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35078, June 30, 1993]
[61 FR 31431, June 20, 1996]
In every building or structure exits shall be so arranged and maintained as to provide free and unobstructed egress from all parts of the building or structure at all times when it is occupied. No lock or fastening to prevent free escape from the inside of any building shall be installed except in mental, penal, or corrective institutions where supervisory personnel is continually on duty and effective provisions are made to remove occupants in case of fire or other emergency.
Exits shall be marked by a readily visible sign. Access to exits shall be marked by readily visible signs in all cases where the exit or way to reach it is not immediately visible to the occupants.
Means of egress shall be continually maintained free of all obstructions or impediments to full instant use in the case of fire or other emergency.
[58 FR 35083, June 30, 1993]
This section applies to all emergency action plans required by a particular OSHA standard. The emergency action plan shall be in writing (except as provided in the last sentence of paragraph (e)(3) of this section) and shall cover those designated actions employers and employees must take to ensure employee safety from fire and other emergencies.
The following elements, at a minimum, shall be included in the plan:
The employer shall establish in the emergency action plan the types of evacuation to be used in emergency circumstances.
[58 FR 35083, June 30, 1993]
Appendix A to § 1926.50—First aid Kits (Non-Mandatory)
First aid supplies are required to be easily accessible under paragraph § 1926.50(d)(1). An example of the minimal contents of a generic first aid kit is described in American National Standard (ANSI) Z308.1-1978 “Minimum Requirements for Industrial Unit-Type First-aid Kits”. The contents of the kit listed in the ANSI standard should be adequate for small work sites. When larger operations or multiple operations are being conducted at the same location, employers should determine the need for additional first aid kits at the worksite, additional types of first aid equipment and supplies and additional quantities and types of supplies and equipment in the first aid kits.
In a similar fashion, employers who have unique or changing first-aid needs in their workplace may need to enhance their first-aid kits. The employer can use the OSHA 300 log, OSHA 301 log, or other reports to identify these unique problems. Consultation from the local fire/rescue department, appropriate medical professional, or local emergency room may be helpful to employers in these circumstances. By assessing the specific needs of their workplace, employers can ensure that reasonably anticipated supplies are available. Employers should assess the specific needs of their worksite periodically and augment the first aid kit appropriately.
If it is reasonably anticipated employees will be exposed to blood or other potentially infectious materials while using first-aid supplies, employers should provide personal protective equipment (PPE). Appropriate PPE includes gloves, gowns, face shields, masks and eye protection (see “Occupational Exposure to Blood borne Pathogens”, 29 CFR 1910.1030(d)(3)) (56 FR 64175).
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 49 FR 18295, Apr. 30, 1984; 58 FR 35084, June 30, 1993; 61 FR 5510, Feb. 13, 1996; 63 FR 33469, June 18, 1998; 76 FR 80740, Dec. 27, 2011; 84 FR 21575, May 14, 2019]
| Number of employees | Minimum number of facilities |
|---|---|
| 20 or less | 1. |
| 20 or more | 1 toilet seat and 1 urinal per 40 workers. |
| 200 or more | 1 toilet seat and 1 urinal per 50 workers. |
When temporary sleeping quarters are provided, they shall be heated, ventilated, and lighted.
Washing facilities shall be maintained in a sanitary condition.
No employee shall be allowed to consume food or beverages in a toilet room nor in any area exposed to a toxic material.
Every enclosed workplace shall be so constructed, equipped, and maintained, so far as reasonably practicable, as to prevent the entrance or harborage of rodents, insects, and other vermin. A continuing and effective extermination program shall be instituted where their presence is detected.
Whenever employees are required by a particular standard to wear protective clothing because of the possibility of contamination with toxic materials, change rooms equipped with storage facilities for street clothes and separate storage facilities for the protective clothing shall be provided.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35084, June 30, 1993; 76 FR 33611, June 8, 2011]
| Duration per day, hours | Sound level dBA slow response |
|---|---|
| 8 | 90 |
| 6 | 92 |
| 4 | 95 |
| 3 | 97 |
| 2 | 100 |
| 1 1 ⁄ 2 | 102 |
| 1 | 105 |
| 1 ⁄ 2 | 110 |
| 1 ⁄ 4 or less | 115 |
Where:
F
e
T
L
If the value of F e exceeds unity (1) the exposure exceeds permissible levels.
110 db A 1/4 hour.
100 db A 1/2 hour.
90 db A 1 1/2 hours.
F
e
1/4
1/2
1/2
1/2
F
e
F
e
Since the value of F e does not exceed unity, the exposure is within permissible limits.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 61 FR 5510, Feb. 13, 1996; 61 FR 31431, June 20, 1996]
1 micro-watt per square centimeter;
1 milliwatt per square centimeter;
2 1/2 watts per square centimeter.
An employee's exposure, as determined from breathing-zone air samples, to any substance in Table 1 of this section with a permissible exposure limit preceded by (C) must at no time exceed the exposure limit specified for that substance. If instantaneous monitoring is not feasible, then the employer must assess the ceiling as a 15-minute time-weighted average exposure that the employer cannot exceed at any time during the working day.
An employee's exposure, as determined from breathing-zone air samples, to any substance in Table 1 or 2 of this section with a permissible exposure limit not preceded by (C) must not exceed the limit specified for that substance measured as an 8-hour time-weighted average in any work shift.
| Substance | CAS No. d | ppm a | mg/m 3 b | Skin designation * |
|---|---|---|---|---|
| Abate; see Temephos | ||||
| Acetaldehyde | 75-07-0 | 200 | 360 | — |
| Acetic acid | 64-19-7 | 10 | 25 | — |
| Acetic anhydride | 108-24-7 | 5 | 20 | — |
| Acetone | 67-64-1 | 1000 | 2400 | — |
| Acetonitrile | 75-05-8 | 40 | 70 | — |
| 2-Acetylaminofluorine; see § 1926.1114 | 53-96-3 | |||
| Acetylene | 74-86-2 | E | ||
| Acetylene dichloride; see 1,2-Dichloroethylene | ||||
| Acetylene tetrabromide | 79-27-6 | 1 | 14 | — |
| Acrolein | 107-02-8 | 0.1 | 0.25 | — |
| Acrylamide | 79-06-1 | — | 0.3 | X |
| Acrylonitrile; see § 1926.1145 | 107-13-1 | |||
| Aldrin | 309-00-2 | — | 0.25 | X |
| Allyl alcohol | 107-18-6 | 2 | 5 | X |
| Allyl chloride | 107-05-1 | 1 | 3 | — |
| Allyl glycidyl ether (AGE) | 106-92-3 | (C)10 | (C)45 | — |
| Allyl propyl disulfide | 2179-59-1 | 2 | 12 | — |
| alpha-Alumina | 1344-28-1 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Alundum; see alpha-Alumina | ||||
| 4-Aminodiphenyl; see § 1926.1111 | 92-67-1 | |||
| 2-Aminoethanol; see Ethanolamine | ||||
| 2-Aminopyridine | 504-29-0 | 0.5 | 2 | — |
| Ammonia | 7664-41-7 | 50 | 35 | — |
| Ammonium sulfamate | 7773-06-0 | |||
| Total dust | — | 15 | — | |
| Respirable fraction | — | 5 | — | |
| n-Amyl acetate | 628-63-7 | 100 | 525 | — |
| sec-Amyl acetate | 626-38-0 | 125 | 650 | — |
| Aniline and homologs | 62-53-3 | 5 | 19 | X |
| Anisidine (o-, p-isomers) | 29191-52-4 | — | 0.5 | X |
| Antimony and compounds (as Sb) | 7440-36-0 | — | 0.5 | — |
| ANTU (alpha Naphthylthiourea) | 86-88-4 | — | 0.3 | — |
| Argon | 7440-37-1 | E | ||
| Arsenic, inorganic compounds (as As); see § 1926.1118 | 7440-38-2 | — | — | — |
| Arsenic, organic compounds (as As) | 7440-38-2 | — | 0.5 | — |
| Arsine | 7784-42-1 | 0.05 | 0.2 | — |
| Asbestos; see § 1926.1101 | ||||
| Azinphos-methyl | 86-50-0 | — | 0.2 | X |
| Barium, soluble compounds (as Ba) | 7440-39-3 | — | 0.5 | — |
| Benzene g ; see § 1926.1128 | 71-43-2 | |||
| Benzidine; see § 1926.1110 | 92-87-5 | |||
| p-Benzoquinone; see Quinone | ||||
| Benzo(a)pyrene; see Coal tar pitch volatiles | ||||
| Benzoyl peroxide | 94-36-0 | — | 5 | — |
| Benzyl chloride | 100-44-7 | 1 | 5 | — |
| Beryllium and beryllium compounds (as Be); see 1926.1124 (q) | 7440-41-7 | — | 0.002 | — |
| Biphenyl; see Diphenyl | ||||
| Bisphenol A; see Diglycidyl ether | ||||
| Boron oxide | 1303-86-2 | |||
| Total dust | — | 15 | — | |
| Boron tribromide | 10294-33-4 | 1 | 10 | — |
| Boron trifluoride | 7637-07-2 | (C)1 | (C)3 | — |
| Bromine | 7726-95-6 | 0.1 | 0.7 | — |
| Bromine pentafluoride | 7789-30-2 | 0.1 | 0.7 | — |
| Bromoform | 75-25-2 | 0.5 | 5 | X |
| Butadiene (1,3-Butadiene); see 29 CFR 1910.1051; 29 CFR 1910.19(l) | 106-99-0 | STEL 1 ppm/5 ppm | — | |
| Butanethiol; see Butyl mercaptan | ||||
| 2-Butanone (Methyl ethyl ketone) | 78-93-3 | 200 | 590 | — |
| 2-Butoxyethanol | 111-76-2 | 50 | 240 | X |
| n-Butyl-acetate | 123-86-4 | 150 | 710 | — |
| sec-Butyl acetate | 105-46-4 | 200 | 950 | — |
| tert-Butyl acetate | 540-88-5 | 200 | 950 | — |
| n-Butyl alcohol | 71-36-3 | 100 | 300 | — |
| sec-Butyl alcohol | 78-92-2 | 150 | 450 | — |
| tert-Butyl alcohol | 75-65-0 | 100 | 300 | — |
| Butylamine | 109-73-9 | (C)5 | (C)15 | X |
| tert-Butyl chromate (as CrO 3 ); see 1926.1126 n | 1189-85-1 | |||
| n-Butyl glycidyl ether (BGE) | 2426-08-6 | 50 | 270 | — |
| Butyl mercaptan | 109-79-5 | 0.5 | 1.5 | — |
| p-tert-Butyltoluene | 98-51-1 | 10 | 60 | — |
| Cadmium (as Cd); see 1926.1127 | 7440-43-9 | |||
| Calcium carbonate | 1317-65-3 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Calcium oxide | 1305-78-8 | — | 5 | — |
| Calcium sulfate | 7778-18-9 | |||
| Total dust | — | 15 | — | |
| Respirable fraction | — | 5 | — | |
| Camphor, synthetic | 76-22-2 | — | 2 | — |
| Carbaryl (Sevin) | 63-25-2 | — | 5 | — |
| Carbon black | 1333-86-4 | — | 3.5 | — |
| Carbon dioxide | 124-38-9 | 5000 | 9000 | — |
| Carbon disulfide | 75-15-0 | 20 | 60 | X |
| Carbon monoxide | 630-08-0 | 50 | 55 | — |
| Carbon tetrachloride | 56-23-5 | 10 | 65 | X |
| Cellulose | 9004-34-6 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Chlordane | 57-74-9 | — | 0.5 | X |
| Chlorinated camphene | 8001-35-2 | — | 0.5 | X |
| Chlorinated diphenyl oxide | 55720-99-5 | — | 0.5 | — |
| Chlorine | 7782-50-5 | 1 | 3 | — |
| Chlorine dioxide | 10049-04-4 | 0.1 | 0.3 | |
| Chlorine trifluoride | 7790-91-2 | (C)0.1 | (C)0.4 | — |
| Chloroacetaldehyde | 107-20-0 | (C)1 | (C)3 | — |
| a-Chloroacetophenone (Phenacyl chloride) | 532-27-4 | 0.05 | 0.3 | — |
| Chlorobenzene | 108-90-7 | 75 | 350 | — |
| o-Chlorobenzylidene malononitrile | 2698-41-1 | 0.05 | 0.4 | — |
| Chlorobromomethane | 74-97-5 | 200 | 1050 | — |
| 2-Chloro-1,3-butadiene; see beta-Chloroprene | ||||
| Chlorodiphenyl (42% Chlorine) (PCB) | 53469-21-9 | — | 1 | X |
| Chlorodiphenyl (54% Chlorine) (PCB) | 11097-69-1 | — | 0.5 | X |
| 1-Chloro,2,3-epoxypropane; see Epichlorohydrin | ||||
| 2-Chloroethanol; see Ethylene chlorohydrin | ||||
| Chloroethylene; see Vinyl chloride | ||||
| Chloroform (Trichloromethane) | 67-66-3 | (C)50 | (C)240 | — |
| bis(Chloromethyl) ether; see § 1926.1108 | 542-88-1 | |||
| Chloromethyl methyl ether; see § 1926.1106 | 107-30-2 | |||
| 1-Chloro-1-nitropropane | 600-25-9 | 20 | 100 | — |
| Chloropicrin | 76-06-2 | 0.1 | 0.7 | — |
| beta-Chloroprene | 126-99-8 | 25 | 90 | X |
| Chromium (II) compounds | ||||
| (as Cr) | 7440-47-3 | — | 0.5 | — |
| Chromium (III) compounds | ||||
| (as Cr) | 7440-47-3 | — | 0.5 | — |
| Chromium (VI) compounds; See 1926.1126 o | ||||
| Chromium metal and insol. salts (as Cr) | 7440-47-3 | — | 1 | — |
| Chrysene; see Coal tar pitch volatiles | ||||
| Coal tar pitch volatiles (benzene soluble fraction), anthracene, BaP, phenanthrene, acridine, chrysene, pyrene | 65996-93-2 | — | 0.2 | — |
| Cobalt metal, dust, and fume (as Co) | 7440-48-4 | — | 0.1 | — |
| Copper | 7440-50-8 | |||
| Fume (as Cu) | — | 0.1 | — | |
| Dusts and mists (as Cu) | — | 1 | — | |
| Corundum; see Emery | ||||
| Cotton dust (raw) | — | 1 | ||
| Crag herbicide (Sesone) | 136-78-7 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Cresol, all isomers | 1319-77-3 | 5 | 22 | X |
| Crotonaldehyde | 123-73-9; | 2 | 6 | |
| 4170-30-3 | ||||
| Cumene | 98-82-8 | 50 | 245 | X |
| Cyanides (as CN) | Varies with Compound | — | 5 | X |
| Cyanogen | 460-19-5 | 10 | — | — |
| Cyclohexane | 110-82-7 | 300 | 1050 | — |
| Cyclohexanol | 108-93-0 | 50 | 200 | — |
| Cyclohexanone | 108-94-1 | 50 | 200 | — |
| Cyclohexene | 110-83-8 | 300 | 1015 | — |
| Cyclonite | 121-82-4 | — | 1.5 | X |
| Cyclopentadiene | 542-92-7 | 75 | 200 | — |
| DDT, see Dichlorodiphenyltrichloroethane | ||||
| DDVP, see Dichlorvos | ||||
| 2,4-D (Dichlorophenoxyacetic acid) | 94-75-7 | — | 10 | — |
| Decaborane | 17702-41-9 | 0.05 | 0.3 | X |
| Demeton (Systox) | 8065-48-3 | — | 0.1 | X |
| Diacetone alcohol (4-Hydroxy-4-methyl-2-pentanone) | 123-42-2 | 50 | 240 | — |
| 1,2-Diaminoethane; see Ethylenediamine | ||||
| Diazomethane | 334-88-3 | 0.2 | 0.4 | — |
| Diborane | 19287-45-7 | 0.1 | 0.1 | — |
| 1,2-Dibromo-3-chloropropane (DBCP); see § 1926.1144 | 96-12-8 | — | ||
| 1,2-Dibromoethane; see Ethylene dibromide | ||||
| Dibutyl phosphate | 107-66-4 | 1 | 5 | — |
| Dibutyl phthalate | 84-74-2 | — | 5 | — |
| Dichloroacetylene | 7572-29-4 | (C)0.1 | (C)0.4 | — |
| o-Dichlorobenzene | 95-50-1 | (C)50 | (C)300 | — |
| p-Dichlorobenzene | 106-46-7 | 75 | 450 | — |
| 3,3′-Dichlorobenzidine; see § 1926.1107 | 91-94-1 | |||
| Dichlorodifluoromethane | 75-71-8 | 1000 | 4950 | — |
| 1,3-Dichloro-5,5-dimethyl hydantoin | 118-52-5 | — | 0.2 | — |
| Dichlorodiphenyltrichloroethane (DDT) | 50-29-3 | — | 1 | X |
| 1,1-Dichloroethane | 75-34-3 | 100 | 400 | — |
| 1,2-Dichloroethane; see Ethylene dichloride | ||||
| 1,2-Dichloroethylene | 540-59-0 | 200 | 790 | — |
| Dichloroethyl ether | 111-44-4 | (C)15 | (C)90 | X |
| Dichloromethane; see Methylene chloride | ||||
| Dichloromonofluoromethane | 75-43-4 | 1000 | 4200 | — |
| 1,1-Dichloro-1-nitroethane | 594-72-9 | (C)10 | (C)60 | — |
| 1,2-Dichloropropane; see Propylene dichloride | ||||
| Dichlorotetrafluoroethane | 76-14-2 | 1000 | 7000 | — |
| Dichlorvos (DDVP) | 62-73-7 | — | 1 | X |
| Dieldrin | 60-57-1 | — | 0.25 | X |
| Diethylamine | 109-89-7 | 25 | 75 | — |
| 2-Diethylaminoethanol | 100-37-8 | 10 | 50 | X |
| Diethylene triamine | 111-40-0 | (C)10 | (C)42 | X |
| Diethyl ether; see Ethyl ether | ||||
| Difluorodibromomethane | 75-61-6 | 100 | 860 | — |
| Diglycidyl ether (DGE) | 2238-07-5 | (C)0.5 | (C)2.8 | — |
| Dihydroxybenzene; see Hydroquinone | ||||
| Diisobutyl ketone | 108-83-8 | 50 | 290 | — |
| Diisopropylamine | 108-18-9 | 5 | 20 | X |
| 4-Dimethylaminoazobenzene; see § 1926.1115 | 60-11-7 | |||
| Dimethoxymethane; see Methylal | ||||
| Dimethyl acetamide | 127-19-5 | 10 | 35 | X |
| Dimethylamine | 124-40-3 | 10 | 18 | — |
| Dimethylaminobenzene; see Xylidine | ||||
| Dimethylaniline (N,N-Dimethylaniline) | 121-69-7 | 5 | 25 | X |
| Dimethylbenzene; see Xylene | ||||
| Dimethyl-1,2-dibromo- 2,2-dichloroethyl phosphate | 300-76-5 | — | 3 | — |
| Dimethylformamide | 68-12-2 | 10 | 30 | X |
| 2,6-Dimethyl-4-heptanone; see Diisobutyl ketone | ||||
| 1,1-Dimethylhydrazine | 57-14-7 | 0.5 | 1 | X |
| Dimethylphthalate | 131-11-3 | — | 5 | — |
| Dimethyl sulfate | 77-78-3 | 1 | 5 | X |
| Dinitrobenzene (all isomers) | 1 | X | ||
| (ortho) | 528-29-0 | |||
| (meta) | 99-65-0 | |||
| (para) | 100-25-4 | |||
| Dinitro-o-cresol | 534-52-1 | — | 0.2 | X |
| Dinitrotoluene | 25321-14-6 | — | 1.5 | X |
| Dioxane (Diethylene dioxide) | 123-91-1 | 100 | 360 | X |
| Diphenyl (Biphenyl) | 92-52-4 | 0.2 | 1 | — |
| Diphenylamine | 122-39-4 | — | 10 | — |
| Diphenylmethane diisocyanate; see Methylene bisphenyl isocyanate | ||||
| Dipropylene glycol methyl ether | 34590-94-8 | 100 | 600 | X |
| Di-sec octyl phthalate (Di-(2-ethylhexyl) phthalate) | 117-81-7 | — | 5 | — |
| Emery | 12415-34-8 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Endosulfan | 115-29-7 | — | 0.1 | X |
| Endrin | 72-20-8 | — | 0.1 | X |
| Epichlorohydrin | 106-89-8 | 5 | 19 | X |
| EPN | 2104-64-5 | — | 0.5 | X |
| 1,2-Epoxypropane; see Propylene oxide | ||||
| 2,3-Epoxy-1-propanol; see Glycidol | ||||
| Ethane | 74-84-0 | E | ||
| Ethanethiol; see Ethyl mercaptan | ||||
| Ethanolamine | 141-43-5 | 3 | 6 | — |
| 2-Ethoxyethanol (Cellosolve) | 110-80-5 | 200 | 740 | X |
| 2-Ethoxyethyl acetate (Cellosolve acetate) | 111-15-9 | 100 | 540 | X |
| Ethyl acetate | 141-78-6 | 400 | 1400 | — |
| Ethyl acrylate | 140-88-5 | 25 | 100 | X |
| Ethyl alcohol (Ethanol) | 64-17-5 | 1000 | 1900 | — |
| Ethylamine | 75-04-7 | 10 | 18 | — |
| Ethyl amyl ketone (5-Methyl-3-heptanone) | 541-85-5 | 25 | 130 | — |
| Ethyl benzene | 100-41-4 | 100 | 435 | — |
| Ethyl bromide | 74-96-4 | 200 | 890 | — |
| Ethyl butyl ketone (3-Heptanone) | 106-35-4 | 50 | 230 | — |
| Ethyl chloride | 75-00-3 | 1000 | 2600 | — |
| Ethyl ether | 60-29-7 | 400 | 1200 | — |
| Ethyl formate | 109-94-4 | 100 | 300 | — |
| Ethyl mercaptan | 75-08-1 | 0.5 | 1 | — |
| Ethyl silicate | 78-10-4 | 100 | 850 | — |
| Ethylene | 74-85-1 | E | ||
| Ethylene chlorohydrin | 107-07-3 | 5 | 16 | X |
| Ethylenediamine | 107-15-3 | 10 | 25 | — |
| Ethylene dibromide | 106-93-4 | (C)25 | (C)190 | X |
| Ethylene dichloride (1,2-Dichloroethane) | 107-06-2 | 50 | 200 | — |
| Ethylene glycol dinitrate | 628-96-6 | (C)0.2 | (C)1 | X |
| Ethylene glycol methyl acetate; see Methyl cellosolve acetate | ||||
| Ethyleneimine; see § 1926.1112 | 151-56-4 | |||
| Ethylene oxide; see § 1926.1147 | 75-21-8 | |||
| Ethylidene chloride; see 1,1-Dichloroethane | ||||
| N-Ethylmorpholine | 100-74-3 | 20 | 94 | X |
| Ferbam | 14484-64-1 | |||
| Total dust | — | 15 | — | |
| Ferrovanadium dust | 12604-58-9 | — | 1 | — |
| Fibrous Glass | ||||
| Total dust | — | |||
| Respirable fraction | — | — | ||
| Fluorides (as F) | Varies with compound | — | 2.5 | — |
| Fluorine | 7782-41-4 | 0.1 | 0.2 | — |
| Fluorotrichloromethane (Trichlorofluoromethane) | 75-69-4 | 1000 | 5600 | — |
| Formaldehyde; see § 1926.1148 | 50-00-0 | |||
| Formic acid | 64-18-6 | 5 | 9 | — |
| Furfural | 98-01-1 | 5 | 20 | X |
| Furfuryl alcohol | 98-00-0 | 50 | 200 | — |
| Gasoline | 8006-61-9 | A 3 | — | |
| Glycerin (mist) | 56-81-5 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Glycidol | 556-52-5 | 50 | 150 | — |
| Glycol monoethyl ether; see 2-Ethoxyethanol | ||||
| Graphite, natural, respirable dust | 7782-42-5 | ( 2 ) | ( 2 ) | ( 2 ) |
| Graphite, synthetic | ||||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Guthion; see Azinphos methyl | ||||
| Gypsum | 13397-24-5 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Hafnium | 7440-58-6 | — | 0.5 | — |
| Helium | 7440-59-7 | E | ||
| Heptachlor | 76-44-8 | — | 0.5 | X |
| Heptane (n-Heptane) | 142-82-5 | 500 | 2000 | — |
| Hexachloroethane | 67-72-1 | 1 | 10 | X |
| Hexachloronaphthalene | 1335-87-1 | — | 0.2 | X |
| n-Hexane | 110-54-3 | 500 | 1800 | — |
| 2-Hexanone (Methyl n-butyl ketone) | 591-78-6 | 100 | 410 | — |
| Hexone (Methyl isobutyl ketone) | 108-10-1 | 100 | 410 | — |
| sec-Hexyl acetate | 108-84-9 | 50 | 300 | — |
| Hydrazine | 302-01-2 | 1 | 1.3 | X |
| Hydrogen | 1333-74-0 | E | ||
| Hydrogen bromide | 10035-10-6 | 3 | 10 | — |
| Hydrogen chloride | 7647-01-0 | (C)5 | (C)7 | — |
| Hydrogen cyanide | 74-90-8 | 10 | 11 | X |
| Hydrogen fluoride (as F) | 7664-39-3 | 3 | 2 | — |
| Hydrogen peroxide | 7722-84-1 | 1 | 1.4 | — |
| Hydrogen selenide (as Se) | 7783-07-5 | 0.05 | .02 | — |
| Hydrogen sulfide | 7783-06-4 | 10 | 15 | — |
| Hydroquinone | 123-31-9 | — | 2 | — |
| Indene | 95-13-6 | 10 | 45 | — |
| Indium and compounds (as In) | 7440-74-6 | — | 0.1 | — |
| Iodine | 7553-56-2 | (C)0.1 | (C)1 | — |
| Iron oxide fume | 1309-37-1 | — | 10 | — |
| Iron salts (soluble) (as Fe) | Varies with compound | — | 1 | — |
| Isoamyl acetate | 123-92-2 | 100 | 525 | — |
| Isoamyl alcohol (primary and secondary) | 123-51-3 | 100 | 360 | — |
| Isobutyl acetate | 110-19-0 | 150 | 700 | — |
| Isobutyl alcohol | 78-83-1 | 100 | 300 | — |
| Isophorone | 78-59-1 | 25 | 140 | — |
| Isopropyl acetate | 108-21-4 | 250 | 950 | — |
| Isopropyl alcohol | 67-63-0 | 400 | 980 | — |
| Isopropylamine | 75-31-0 | 5 | 12 | — |
| Isopropyl ether | 108-20-3 | 500 | 2100 | — |
| Isopropyl glycidyl ether (IGE) | 4016-14-2 | 50 | 240 | — |
| Kaolin | 1332-58-7 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Ketene | 463-51-4 | 0.5 | 0.9 | — |
| Lead, inorganic (as Pb); see 1926.62 | 7439-92-1 | |||
| Limestone | 1317-65-3 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Lindane | 58-89-9 | — | 0.5 | X |
| Lithium hydride | 7580-67-8 | — | 0.025 | — |
| L.P.G. (Liquefied petroleum gas) | 68476-85-7 | 1000 | 1800 | |
| Magnesite | 546-93-0 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Magnesium oxide fume | 1309-48-4 | |||
| Total particulate | 15 | — | — | |
| Malathion | 121-75-5 | |||
| Total dust | — | 15 | X | |
| Maleic anhydride | 108-31-6 | 0.25 | ||
| Manganese compounds (as Mn) | 7439-96-5 | — | (C)5 | — |
| Manganese fume (as Mn) | 7439-96-5 | — | (C)5 | — |
| Marble | 1317-65-3 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Mercury (aryl and inorganic)(as Hg) | 7439-97-6 | 0.1 | X | |
| Mercury (organo) alkyl compounds (as Hg) | 7439-97-6 | — | 0.01 | X |
| Mercury (vapor) (as Hg) | 7439-97-6 | — | 0.1 | X |
| Mesityl oxide | 141-79-7 | 25 | 100 | — |
| Methane | 74-82-8 | E | ||
| Methanethiol; see Methyl mercaptan | ||||
| Methoxychlor | 72-43-5 | |||
| Total dust | — | 15 | — | |
| 2-Methoxyethanol (Methyl cellosolve) | 109-86-4 | 25 | 80 | X |
| 2-Methoxyethyl acetate (Methyl cellosolve acetate) | 110-49-6 | 25 | 120 | X |
| Methyl acetate | 79-20-9 | 200 | 610 | — |
| Methyl acetylene (Propyne) | 74-99-7 | 1000 | 1650 | — |
| Methyl acetylene-propadiene mixture (MAPP) | 1000 | 1800 | — | |
| Methyl acrylate | 96-33-3 | 10 | 35 | X |
| Methylal (Dimethoxy-methane) | 109-87-5 | 1000 | 3100 | — |
| Methyl alcohol | 67-56-1 | 200 | 260 | — |
| Methylamine | 74-89-5 | 10 | 12 | — |
| Methyl amyl alcohol; see Methyl isobutyl carbinol | ||||
| Methyl n-amyl ketone | 110-43-0 | 100 | 465 | — |
| Methyl bromide | 74-83-9 | (C)20 | (C)80 | X |
| Methyl butyl ketone; see 2-Hexanone | ||||
| Methyl cellosolve; see 2-Methoxyethanol | ||||
| Methyl cellosolve acetate; see 2-Methoxyethyl acetate | ||||
| Methylene chloride; see § 1910.1052 | ||||
| Methyl chloroform (1,1,1-Trichloroethane) | 71-55-6 | 350 | 1900 | — |
| Methylcyclohexane | 108-87-2 | 500 | 2000 | — |
| Methylcyclohexanol | 25639-42-3 | 100 | 470 | — |
| o-Methylcyclohexanone | 583-60-8 | 100 | 460 | X |
| Methylene chloride | 75-09-2 | 500 | 1740 | — |
| Methylenedianiline (MDA) | 101-77-9 | |||
| Methyl ethyl ketone (MEK); see 2-Butanone | ||||
| Methyl formate | 107-31-3 | 100 | 250 | — |
| Methyl hydrazine (Monomethyl hydrazine) | 60-34-4 | (C)0.2 | (C)0.35 | X |
| Methyl iodide | 74-88-4 | 5 | 28 | X |
| Methyl isoamyl ketone | 110-12-3 | 100 | 475 | — |
| Methyl isobutyl carbinol | 108-11-2 | 25 | 100 | X |
| Methyl isobutyl ketone; see Hexone | ||||
| Methyl isocyanate | 624-83-9 | 0.02 | 0.05 | X |
| Methyl mercaptan | 74-93-1 | 0.5 | 1 | — |
| Methyl methacrylate | 80-62-6 | 100 | 410 | — |
| Methyl propyl ketone; see 2-Pentanone | ||||
| Methyl silicate | 681-84-5 | (C)5 | (C)30 | — |
| alpha-Methyl styrene | 98-83-9 | (C)100 | (C)480 | — |
| Methylene bisphenyl isocyanate (MDI) | 101-68-8 | (C)0.02 | (C)0.2 | — |
| Mica; see Silicates | ||||
| Molybdenum (as Mo) | 7439-98-7 | |||
| Soluble compounds | — | 5 | — | |
| Insoluble compounds | ||||
| Total dust | — | 15 | — | |
| Monomethyl aniline | 100-61-8 | 2 | 9 | X |
| Monomethyl hydrazine; see Methyl hydrazine | ||||
| Morpholine | 110-91-8 | 20 | 70 | X |
| Naphtha (Coal tar) | 8030-30-6 | 100 | 400 | — |
| Naphthalene | 91-20-3 | 10 | 50 | — |
| alpha-Naphthylamine; see § 1926.1104 | 134-32-7 | |||
| beta-Naphthylamine; see § 1926.1109 | 91-59-8 | — | ||
| Neon | 7440-01-9 | E | ||
| Nickel carbonyl (as Ni) | 13463-39-3 | 0.001 | 0.007 | — |
| Nickel, metal and insoluble compounds (as Ni) | 7440-02-0 | — | 1 | — |
| Nickel, soluble compounds (as Ni) | 7440-02-0 | — | 1 | — |
| Nicotine | 54-11-5 | — | 0.5 | X |
| Nitric acid | 7697-37-2 | 2 | 5 | — |
| Nitric oxide | 10102-43-9 | 25 | 30 | — |
| p-Nitroaniline | 100-01-6 | 1 | 6 | X |
| Nitrobenzene | 98-95-3 | 1 | 5 | X |
| p-Nitrochlorobenzene | 100-00-5 | — | 1 | X |
| 4-Nitrodiphenyl; see § 1926.1103 | 92-93-3 | |||
| Nitroethane | 79-24-3 | 100 | 310 | — |
| Nitrogen | 7727-37-9 | E | ||
| Nitrogen dioxide | 10102-44-0 | (C)5 | (C)9 | — |
| Nitrogen trifluoride | 7783-54-2 | 10 | 29 | — |
| Nitroglycerin | 55-63-0 | (C)0.2 | (C)2 | X |
| Nitromethane | 75-52-5 | 100 | 250 | — |
| 1-Nitropropane | 108-03-2 | 25 | 90 | — |
| 2-Nitropropane | 79-46-9 | 25 | 90 | — |
| N-Nitrosodimethylamine; see § 1926.1116 | 62-79-9 | — | ||
| Nitrotoluene (all isomers) | 5 | 30 | X | |
| o-isomer | 88-72-2; | |||
| m-isomer | 99-08-1; | |||
| p-isomer | 99-99-0 | |||
| Nitrotrichloromethane; see Chloropicrin | ||||
| Nitrous oxide | 10024-97-2 | E | ||
| Octachloronaphthalene | 2234-13-1 | — | 0.1 | X |
| Octane | 111-65-9 | 400 | 1900 | — |
| Oil mist, mineral | 8012-95-1 | — | 5 | — |
| Osmium tetroxide (as Os) | 20816-12-0 | — | 0.002 | — |
| Oxalic acid | 144-62-7 | — | 1 | — |
| Oxygen difluoride | 7783-41-7 | 0.05 | 0.1 | — |
| Ozone | 10028-15-6 | 0.1 | 0.2 | — |
| Paraquat, respirable dust | 4685-14-7; | — | 0.5 | X |
| 1910-42-5; | ||||
| 2074-50-2 | ||||
| Parathion | 56-38-2 | — | 0.1 | X |
| Particulates not otherwise regulated | ||||
| Total dust organic and inorganic | — | 15 | — | |
| PCB; see Chlorodiphenyl (42% and 54% chlorine) | ||||
| Pentaborane | 19624-22-7 | 0.005 | 0.01 | — |
| Pentachloronaphthalene | 1321-64-8 | — | 0.5 | X |
| Pentachlorophenol | 87-86-5 | — | 0.5 | X |
| Pentaerythritol | 115-77-5 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Pentane | 109-66-0 | 500 | 1500 | — |
| 2-Pentanone (Methyl propyl ketone) | 107-87-9 | 200 | 700 | — |
| Perchloroethylene (Tetrachloroethylene) | 127-18-4 | 100 | 670 | — |
| Perchloromethyl mercaptan | 594-42-3 | 0.1 | 0.8 | — |
| Perchloryl fluoride | 7616-94-6 | 3 | 13.5 | — |
| Petroleum distillates (Naphtha)(Rubber Solvent) | A 3 | — | ||
| Phenol | 108-95-2 | 5 | 19 | X |
| p-Phenylene diamine | 106-50-3 | — | 0.1 | X |
| Phenyl ether, vapor | 101-84-8 | 1 | 7 | — |
| Phenyl ether-biphenyl mixture, vapor | 1 | 7 | — | |
| Phenylethylene; see Styrene | ||||
| Phenyl glycidyl ether (PGE) | 122-60-1 | 10 | 60 | — |
| Phenylhydrazine | 100-63-0 | 5 | 22 | X |
| Phosdrin (Mevinphos) | 7786-34-7 | — | 0.1 | X |
| Phosgene (Carbonyl chloride) | 75-44-5 | 0.1 | 0.4 | — |
| Phosphine | 7803-51-2 | 0.3 | 0.4 | — |
| Phosphoric acid | 7664-38-2 | — | 1 | — |
| Phosphorus (yellow) | 7723-14-0 | — | 0.1 | — |
| Phosphorus pentachloride | 10026-13-8 | — | 1 | — |
| Phosphorus pentasulfide | 1314-80-3 | — | 1 | — |
| Phosphorus trichloride | 7719-12-2 | 0.5 | 3 | — |
| Phthalic anhydride | 85-44-9 | 2 | 12 | — |
| Picric acid | 88-89-1 | — | 0.1 | X |
| Pindone (2-Pivalyl-1,3-indandione) | 83-26-1 | — | 0.1 | — |
| Plaster of Paris | 26499-65-0 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Platinum (as Pt) | 7440-06-4 | |||
| Metal | — | — | — | |
| Soluble salts | — | 0.002 | — | |
| Polytetrafluoroethylene decomposition products | A 2 | |||
| Portland cement | 65997-15-1 | |||
| Total dust | — | 15 | — | |
| Respirable fraction | 5 | — | ||
| Propane | 74-98-6 | E | ||
| Propargyl alcohol | 107-19-7 | 1 | — | X |
| beta-Propriolactone; see § 1926.1113 | 57-57-8 | |||
| n-Propyl acetate | 109-60-4 | 200 | 840 | — |
| n-Propyl alcohol | 71-23-8 | 200 | 500 | — |
| n-Propyl nitrate | 627-13-4 | 25 | 110 | — |
| Propylene dichloride | 78-87-5 | 75 | 350 | — |
| Propylene imine | 75-55-8 | 2 | 5 | X |
| Propylene oxide | 75-56-9 | 100 | 240 | — |
| Propyne; see Methyl acetylene | ||||
| Pyrethrum | 8003-34-7 | — | 5 | — |
| Pyridine | 110-86-1 | 5 | 15 | — |
| Quinone | 106-51-4 | 0.1 | 0.4 | — |
| RDX; see Cyclonite | ||||
| Rhodium (as Rh), metal fume and insoluble compounds | 7440-16-6 | — | 0.1 | — |
| Rhodium (as Rh), soluble compounds | 7440-16-6 | — | 0.001 | — |
| Ronnel | 299-84-3 | — | 10 | — |
| Rotenone | 83-79-4 | — | 5 | — |
| Rouge | ||||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Selenium compounds (as Se) | 7782-49-2 | — | 0.2 | — |
| Selenium hexafluoride (as Se) | 7783-79-1 | 0.05 | 0.4 | — |
| Silica, amorphous, precipitated and gel | 112926-00-8 | ( 2 ) | ( 2 ) | ( 2 ) |
| Silica, amorphous, diatomaceous earth, containing less than 1% crystalline silica | 61790-53-2 | ( 2 ) | ( 2 ) | ( 2 ) |
| Silica, crystalline, respirable dust | ||||
| Cristobalite; see 1926.1153 | 14464-46-1 | |||
| Quartz; see 1926.1153 5 | 14808-60-7 | |||
| Tripoli (as quartz); see 1926.1153 5 | 1317-95-9 | |||
| Tridymite; see 1926.1153 | 15468-32-3 | |||
| Silica, fused, respirable dust | 60676-86-0 | ( 2 ) | ( 2 ) | ( 2 ) |
| Silicates (less than 1% crystalline silica) | ||||
| Mica (respirable dust) | 12001-26-2 | ( 2 ) | ( 2 ) | ( 2 ) |
| Soapstone, total dust | ( 2 ) | ( 2 ) | ( 2 ) | |
| Soapstone, respirable dust | ( 2 ) | ( 2 ) | ( 2 ) | |
| Talc (containing asbestos); use asbestos limit; see § 1926.1101 | ||||
| Talc (containing no asbestos), respirable dust | 14807-96-6 | ( 2 ) | ( 2 ) | ( 2 ) |
| Tremolite, asbestiform; see § 1926.1101 | ||||
| Silicon carbide | 409-21-2 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Silver, metal and soluble compounds (as Ag) | 7440-22-4 | — | 0.01 | — |
| Soapstone; see Silicates | ||||
| Sodium fluoroacetate | 62-74-8 | — | 0.05 | X |
| Sodium hydroxide | 1310-73-2 | — | 2 | — |
| Starch | 9005-25-8 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Stibine | 7803-52-3 | 0.1 | 0.5 | — |
| Stoddard solvent | 8052-41-3 | 200 | 1150 | — |
| Strychnine | 57-24-9 | — | 0.15 | — |
| Styrene | 100-42-5 | (C)100 | (C)420 | — |
| Sucrose | 57-50-1 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Sulfur dioxide | 7446-09-5 | 5 | 13 | — |
| Sulfur hexafluoride | 2551-62-4 | 1000 | 6000 | — |
| Sulfuric acid | 7664-93-9 | — | 1 | — |
| Sulfur monochloride | 10025-67-9 | 1 | 6 | — |
| Sulfur pentafluoride | 5714-22-7 | 0.025 | 0.25 | — |
| Sulfuryl fluoride | 2699-79-8 | 5 | 20 | — |
| Systox, see Demeton | ||||
| 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) | 93-76-5 | — | 10 | — |
| Talc; see Silicates— | ||||
| Tantalum, metal and oxide dust | 7440-25-7 | — | 5 | — |
| TEDP (Sulfotep) | 3689-24-5 | — | 0.2 | X |
| Teflon decomposition products | A2 | |||
| Tellurium and compounds (as Te) | 13494-80-9 | — | 0.1 | — |
| Tellurium hexafluoride (as Te) | 7783-80-4 | 0.02 | 0.2 | — |
| Temephos | 3383-96-8 | |||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| TEPP (Tetraethyl pyrophosphate) | 107-49-3 | — | 0.05 | X |
| Terphenyls | 26140-60-3 | (C)1 | (C)9 | — |
| 1,1,1,2-Tetrachloro-2,2-difluoroethane | 76-11-9 | 500 | 4170 | — |
| 1,1,2,2-Tetrachloro-1,2-difluoroethane | 76-12-0 | 500 | 4170 | — |
| 1,1,2,2-Tetrachloroethane | 79-34-5 | 5 | 35 | X |
| Tetrachloroethylene; see Perchloroethylene | ||||
| Tetrachloromethane; see Carbon tetrachloride | ||||
| Tetrachloronaphthalene | 1335-88-2 | — | 2 | X |
| Tetraethyl lead (as Pb) | 78-00-2 | — | 0.1 | X |
| Tetrahydrofuran | 109-99-9 | 200 | 590 | — |
| Tetramethyl lead, (as Pb) | 75-74-1 | — | 0.15 | X |
| Tetramethyl succinonitrile | 3333-52-6 | 0.5 | 3 | X |
| Tetranitromethane | 509-14-8 | 1 | 8 | — |
| Tetryl (2,4,6-Trinitrophenylmethylnitramine) | 479-45-8 | — | 1.5 | X |
| Thallium, soluble compounds (as Tl) | 7440-28-0 | — | 0.1 | X |
| Thiram | 137-26-8 | — | 5 | — |
| Tin, inorganic compounds (except oxides) (as Sn) | 7440-31-5 | — | 2 | — |
| Tin, organic compounds (as Sn) | 7440-31-5 | — | 0.1 | — |
| Tin oxide (as Sn) | 21651-19-4 | — | — | — |
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Titanium dioxide | 13463-67-7 | |||
| Total dust | — | — | ||
| Toluene | 108-88-3 | 200 | 750 | — |
| Toluene-2,4-diisocyanate (TDI) | 584-84-9 | (C)0.02 | (C)0.14 | — |
| o-Toluidine | 95-53-4 | 5 | 22 | X |
| Toxaphene; see Chlorinated camphene | ||||
| Tremolite; see Silicates | ||||
| Tributyl phosphate | 126-73-8 | — | 5 | — |
| 1,1,1-Trichloroethane; see Methyl chloroform | ||||
| 1,1,2-Trichloroethane | 79-00-5 | 10 | 45 | X |
| Trichloroethylene | 79-01-6 | 100 | 535 | — |
| Trichloromethane; see Chloroform | ||||
| Trichloronaphthalene | 1321-65-9 | — | 5 | X |
| 1,2,3-Trichloropropane | 96-18-4 | 50 | 300 | — |
| 1,1,2-Trichloro-1,2,2-trifluoroethane | 76-13-1 | 1000 | 7600 | — |
| Triethylamine | 121-44-8 | 25 | 100 | — |
| Trifluorobromomethane | 75-63-8 | 1000 | 6100 | — |
| Trimethyl benzene | 25551-13-7 | 25 | 120 | — |
| 2,4,6-Trinitrophenol; see Picric acid | ||||
| 2,4,6-Trinitrophenylmethylnitramine; see Tetryl | ||||
| 2,4,6-Trinitrotoluene (TNT) | 118-96-7 | — | 1.5 | X |
| Triorthocresyl phosphate | 78-30-8 | — | 0.1 | — |
| Triphenyl phosphate | 115-86-6 | — | 3 | — |
| Tungsten (as W) | 7440-33-7 | |||
| Insoluble compounds | — | 5 | — | |
| Soluble compounds | — | 1 | — | |
| Turpentine | 8006-64-2 | 100 | 560 | — |
| Uranium (as U) | 7440-61-1 | |||
| Soluble compounds | — | 0.2 | — | |
| Insoluble compounds | — | 0.2 | — | |
| Vanadium | 1314-62-1 | |||
| Respirable dust (as V 2 O 5 ) | — | (C)0.5 | — | |
| Fume (as V 2 O 5 ) | — | (C)0.1 | — | |
| Vegetable oil mist | ||||
| Total dust | — | — | ||
| Respirable fraction | — | — | ||
| Vinyl benzene; see Styrene | ||||
| Vinyl chloride; see § 1926.1117 | 75-01-4 | |||
| Vinyl cyanide; see Acrylonitrile | ||||
| Vinyl toluene | 25013-15-4 | 100 | 480 | — |
| Warfarin | 81-81-2 | — | 0.1 | — |
| Xylenes (o-, m-, p-isomers) | 1330-20-7 | 100 | 435 | — |
| Xylidine | 1300-73-8 | 5 | 25 | X |
| Yttrium | 7440-65-5 | — | 1 | — |
| Zinc chloride fume | 7646-85-7 | — | 1 | — |
| Zinc oxide fume | 1314-13-2 | — | 5 | — |
| Zinc oxide | 1314-13-2 | |||
| Total dust | — | 15 | — | |
| Respirable fraction | — | 5 | — | |
| Zirconium compounds (as Zr) | 7440-67-7 | — | 5 |
| Substance | mppcf (j) |
|---|---|
| SILICA: | |
| Crystalline | 250 (k) |
| Quartz. Threshold Limit calculated from the formula (p) | % SiO 2 + 5 |
| Cristobalite | |
| Amorphous, including natural diatomaceous earth | 20 |
| SILICATES (less than 1% crystalline silica) | |
| Mica | 20 |
| Portland cement | 50 |
| Soapstone | 20 |
| Talc (non-asbestiform) | 20 |
| Talc (fibrous), use asbestos limit | — |
| Graphite (natural) | 15 |
| Inert or Nuisance Particulates: (m) | 50 (or 15 mg/m 3 whichever is the smaller) of total dust <1% SiO 2 |
| [Inert or Nuisance Dusts includes all mineral, inorganic, and organic dusts as indicated by examples in TLV's appendix D] | |
| Conversion factors | |
| mppcf × 35.3 = million particles per cubic meter = particles per c.c. | |
| Footnotes to Tables 1 and 2 of this section: | |
| 1 [Reserved] | |
| 2 See Table 2 of this section. | |
| 3 Use Asbestos Limit § 1926.1101. | |
| 4 [Reserved] | |
| 5 See Table 2 of this section for the exposure limit for any operations or sectors where the exposure limit in § 1926.1153 is stayed or is otherwise not in effect. | |
| * An “X” designation in the “Skin Designation” column indicates that the substance is a dermal hazard. | |
| a Parts of vapor or gas per million parts of contaminated air by volume at 25 °C and 760 torr. | |
| b Milligrams of substance per cubic meter of air. When entry is in this column only, the value is exact; when listed with a ppm entry, it is approximate. | |
| c [Reserved] | |
| d The CAS number is for information only. Enforcement is based on the substance name. For an entry covering more than one metal compound, measured as the metal, the CAS number for the metal is given—not CAS numbers for the individual compounds. | |
| e-f [Reserved] | |
| g For sectors excluded from § 1926.1128 the limit is 10 ppm TWA. | |
| h-i [Reserved] | |
| j Millions of particles per cubic foot of air, based on impinger samples counted by light-field techniques. | |
| k The percentage of crystalline silica in the formula is the amount determined from airborne samples, except in those instances in which other methods have been shown to be applicable. | |
| l [Reserved] | |
| m Covers all organic and inorganic particulates not otherwise regulated. Same as Particulates Not Otherwise Regulated. | |
| n If the exposure limit in § 1926.1126 is stayed or is otherwise not in effect, the exposure limit is a ceiling of 0.1 mg/m 3 . | |
| o If the exposure limit in § 1926.1126 is stayed or is otherwise not in effect, the exposure limit is 0.1 mg/m 3 (as CrO 3 ) as an 8-hour TWA. | |
| p This standard applies to any operations or sectors for which the respirable crystalline silica standard, 1926.1153, is stayed or otherwise is not in effect. | |
| q This standard applies to any operations or sectors for which the beryllium standard, 1926.1124, is stayed or otherwise is not in effect. | |
| The 1970 TLV uses letter designations instead of a numerical value as follows: | |
| A 1 [Reserved] | |
| A 2 Polytetrafluoroethylene decomposition products. Because these products decompose in part by hydrolysis in alkaline solution, they can be quantitatively determined in air as fluoride to provide an index of exposure. No TLV is recommended pending determination of the toxicity of the products, but air concentrations should be minimal. | |
| A 3 Gasoline and/or Petroleum Distillates. The composition of these materials varies greatly and thus a single TLV for all types of these materials is no longer applicable. The content of benzene, other aromatics and additives should be determined to arrive at the appropriate TLV. | |
| E Simple asphyxiants. The limiting factor is the available oxygen which shall be at least 19.5% and be within the requirements addressing explosion in part 1926. |
[39 FR 22801, June 24, 1974, as amended at 51 FR 37007, Oct. 17, 1986; 52 FR 46312, Dec. 4, 1987; 58 FR 35089, June 30, 1993; 61 FR 9249, 9250, Mar. 7, 1996; 61 FR 56856, Nov. 4, 1996; 62 FR 1619, Jan. 10, 1997; 71 FR 10381, Feb. 28, 2006; 71 FR 36009, June 23, 2006; 81 FR 16875, Mar. 25, 2016; 81 FR 31168, May 18, 2016; 81 FR 60273, Sept. 1, 2016; 82 FR 2750, Jan. 9, 2017; 84 FR 21576, May 14, 2019]
Construction areas, ramps, runways, corridors, offices, shops, and storage areas shall be lighted to not less than the minimum illumination intensities listed in Table D-3 while any work is in progress:
| Foot-candles | Area or operation |
|---|---|
| 5 | General construction area lighting. |
| 3 | General construction areas, concrete placement, excavation and waste areas, accessways, active storage areas, loading platforms, refueling, and field maintenance areas. |
| 5 | Indoors: warehouses, corridors, hallways, and exitways. |
| 5 | Tunnels, shafts, and general underground work areas: (Exception: minimum of 10 foot-candles is required at tunnel and shaft heading during drilling, mucking, and scaling. Bureau of Mines approved cap lights shall be acceptable for use in the tunnel heading.) |
| 10 | General construction plant and shops (e.g., batch plants, screening plants, mechanical and electrical equipment rooms, carpenter shops, rigging lofts and active storerooms, barracks or living quarters, locker or dressing rooms, mess halls, and indoor toilets and workrooms). |
| 30 | First aid stations, infirmaries, and offices. |
For areas or operations not covered above, refer to the American National Standard A11.1-1965, R1970, Practice for Industrial Lighting, for recommended values of illumination.
Whenever hazardous substances such as dusts, fumes, mists, vapors, or gases exist or are produced in the course of construction work, their concentrations shall not exceed the limits specified in § 1926.55(a). When ventilation is used as an engineering control method, the system shall be installed and operated according to the requirements of this section.
Local exhaust ventilation when used as described in (a) shall be designed to prevent dispersion into the air of dusts, fumes, mists, vapors, and gases in concentrations causing harmful exposure. Such exhaust systems shall be so designed that dusts, fumes, mists, vapors, or gases are not drawn through the work area of employees.
Exhaust fans, jets, ducts, hoods, separators, and all necessary appurtenances, including refuse receptacles, shall be so designed, constructed, maintained and operated as to ensure the required protection by maintaining a volume and velocity of exhaust air sufficient to gather dusts, fumes, vapors, or gases from said equipment or process, and to convey them to suitable points of safe disposal, thereby preventing their dispersion in harmful quantities into the atmosphere where employees work.
The air outlet from every dust separator, and the dusts, fumes, mists, vapors, or gases collected by an exhaust or ventilating system shall discharge to the outside atmosphere. Collecting systems which return air to work area may be used if concentrations which accumulate in the work area air do not result in harmful exposure to employees. Dust and refuse discharged from an exhaust system shall be disposed of in such a manner that it will not result in harmful exposure to employees.
A solid substance used in an abrasive blasting operation.
A respirator constructed so that it covers the wearer's head, neck, and shoulders to protect the wearer from rebounding abrasive.
A complete enclosure which rotates on an axis, or which has an internal moving tread to tumble the parts, in order to expose various surfaces of the parts to the action of an automatic blast spray.
A complete enclosure in which blasting operations are performed and where the operator works inside of the room to operate the blasting nozzle and direct the flow of the abrasive material.
An enclosure where the operator stands outside and operates the blasting nozzle through an opening or openings in the enclosure.
Air of such purity that it will not cause harm or discomfort to an individual if it is inhaled for extended periods of time.
A device or combination of devices for separating dust from the air handled by an exhaust ventilation system.
A system for removing contaminated air from a space, comprising two or more of the following elements (A) enclosure or hood, (B) duct work, (C) dust collecting equipment, (D) exhauster, and (E) discharge stack.
An air purifying respirator, commonly referred to as a dust or a fume respirator, which removes most of the dust or fume from the air passing through the device.
Airborne dust in sizes capable of passing through the upper respiratory system to reach the lower lung passages.
An enclosure where the pieces to be cleaned are positioned on a rotating table and are passed automatically through a series of blast sprays.
The forcible application of an abrasive to a surface by pneumatic pressure, hydraulic pressure, or centrifugal force.
Air for abrasive-blasting respirators must be free of harmful quantities of dusts, mists, or noxious gases, and must meet the requirements for supplied-air quality and use specified in 29 CFR 1910.134(i).
Dust shall not be permitted to accumulate on the floor or on ledges outside of an abrasive-blasting enclosure, and dust spills shall be cleaned up promptly. Aisles and walkways shall be kept clear of steel shot or similar abrasive which may create a slipping hazard.
This paragraph applies to all operations where an abrasive is forcibly applied to a surface by pneumatic or hydraulic pressure, or by centrifugal force. It does not apply to steam blasting, or steam cleaning, or hydraulic cleaning methods where work is done without the aid of abrasives.
Organic-bonded wheels, the thickness of which is not more than one forty-eighth of their diameter for those up to, and including, 20 inches (50.8 cm) in diameter, and not more than one-sixtieth of their diameter for those larger than 20 inches (50.8 cm) in diameter, used for a multitude of operations variously known as cutting, cutting off, grooving, slotting, coping, and jointing, and the like. The wheels may be “solid” consisting of organic-bonded abrasive material throughout, “steel centered” consisting of a steel disc with a rim of organic-bonded material moulded around the periphery, or of the “inserted tooth” type consisting of a steel disc with organic-bonded abrasive teeth or inserts mechanically secured around the periphery.
All power-driven, flexible, coated bands used for grinding, polishing, or buffing purposes.
The part of an exhaust system piping that is connected directly to the hood or enclosure.
A movable fixture, upon which the part to be ground or polished is placed.
All power-driven rotatable discs faced with abrasive materials, artificial or natural, and used for grinding or polishing on the side of the assembled disc.
The loss in static pressure caused by air flowing into a duct or hood. It is usually expressed in inches of water gauge.
A system consisting of branch pipes connected to hoods or enclosures, one or more header pipes, an exhaust fan, means for separating solid contaminants from the air flowing in the system, and a discharge stack to outside.
All power-driven rotatable grinding or abrasive wheels, except disc wheels as defined in this standard, consisting of abrasive particles held together by artificial or natural bonds and used for peripheral grinding.
A pipe into which one or more branch pipes enter and which connects such branch pipes to the remainder of the exhaust system.
The partial or complete enclosure around the wheel or disc through which air enters an exhaust system during operation.
A grinding machine carrying two power-driven, rotatable, coaxial, horizontal spindles upon the inside ends of which are mounted abrasive disc wheels used for grinding two surfaces simultaneously.
A grinding machine carrying an abrasive disc wheel upon one or both ends of a power-driven, rotatable single horizontal spindle.
All power-driven rotatable wheels composed all or in part of textile fabrics, wood, felt, leather, paper, and may be coated with abrasives on the periphery of the wheel for purposes of polishing, buffing, and light grinding.
Any power-driven rotatable grinding, polishing, or buffing wheel mounted in such manner that it may be manually manipulated.
All power-driven rotatable wheels made from wire or bristles, and used for scratch cleaning and brushing purposes.
Any power-driven rotatable grinding, polishing, or buffing wheel mounted in such a manner that the wheel with its supporting framework can be manipulated over stationary objects.
The kinetic pressure in the direction of flow necessary to cause a fluid at rest to flow at a given velocity. It is usually expressed in inches of water gauge.
A grinding machine having a vertical, rotatable power-driven spindle carrying a horizontal abrasive disc wheel.
Wherever dry grinding, dry polishing or buffing is performed, and employee exposure, without regard to the use of respirators, exceeds the permissible exposure limits prescribed in § 1926.55 or other pertinent sections of this part, a local exhaust ventilation system shall be provided and used to maintain employee exposures within the prescribed limits.
| Wheel diameter, inches (cm) | Wheel width, inches (cm) | Minimum exhaust volume (feet 3 /min.) |
|---|---|---|
| To 9 (22.86) | 1 1 ⁄ 2 (3.81) | 220 |
| Over 9 to 16 (22.86 to 40.64) | 2 (5.08) | 390 |
| Over 16 to 19 (40.64 to 48.26) | 3 (7.62) | 500 |
| Over 19 to 24 (48.26 to 60.96) | 4 (10.16) | 610 |
| Over 24 to 30 (60.96 to 76.2) | 5 (12.7) | 880 |
| Over 30 to 36 (76.2 to 91.44) | 6 (15.24) | 1,200 |
For any wheel wider than wheel diameters shown in Table D-57.1, increase the exhaust volume by the ratio of the new width to the width shown.
Example:
1/2
then 4.5 ÷ 4 × 610 = 686 (rounded to 690).
| Wheel diameter, inches (cm) | Wheel width, inches cm) | Minimum exhaust volume (feet 3 /min.) |
|---|---|---|
| To 9 (22.86) | 2 (5.08) | 300 |
| Over 9 to 16 (22.86 to 40.64) | 3 (7.62) | 500 |
| Over 16 to 19 (40.64 to 48.26) | 4 (10.16) | 610 |
| Over 19 to 24 (48.26 to 60.96) | 5 (12.7) | 740 |
| Over 24 to 30 (60.96 to 76.2) | 6 (15.24) | 1,040 |
| Over 30 to 36 (76.2 to 91.44) | 6 (15.24) | 1,200 |
| Disc diameter, inches (cm) | Exhaust volume (ft. 3 /min.) |
|---|---|
| Up to 12 (30.48) | 220 |
| Over 12 to 19 (30.48 to 48.26) | 390 |
| Over 19 to 30 (48.26 to 76.2) | 610 |
| Over 30 to 36 (76.2 to 91.44) | 880 |
| Disc diameter, inches (cm) | Exhaust volume (ft. 3 /min.) |
|---|---|
| Up to 19 (48.26) | 610 |
| Over 19 to 25 (48.26 to 63.5) | 880 |
| Over 25 to 30 (63.5 to 76.2) | 1,200 |
| Over 30 to 53 (76.2 to 134.62) | 1,770 |
| Over 53 to 72 (134.62 to 182.88) | 6,280 |
| Disc diameter, inches (cm) | One-half or more of disc covered | Disc not covered | ||
|---|---|---|---|---|
| Number 1 | Exhaust foot 3 /min. | Number 1 | Exhaust foot 3 /min. | |
| Up to 20 (50.8) | 1 | 500 | 2 | 780 |
| Over 20 to 30 (50.8 to 76.2) | 2 | 780 | 2 | 1,480 |
| Over 30 to 53 (76.2 to 134.62) | 2 | 1,770 | 4 | 3,530 |
| Over 53 to 72 (134.62 to 182.88) | 2 | 3,140 | 5 | 6,010 |
| 1 Number of exhaust outlets around periphery of hood, or equal distribution provided by other means. |
| Belts width, inches (cm) | Exhaust volume (ft. 3 /min.) |
|---|---|
| Up to 3 (7.62) | 220 |
| Over 3 to 5 (7.62 to 12.7) | 300 |
| Over 5 to 7 (12.7 to 17.78) | 390 |
| Over 7 to 9 (17.78 to 22.86) | 500 |
| Over 9 to 11 (22.86 to 27.94) | 610 |
| Over 11 to 13 (27.94 to 33.02) | 740 |
Where cradles are used for handling the parts to be ground, polished, or buffed, requiring large partial enclosures to house the complete operation, a minimum average air velocity of 150 feet per minute shall be maintained over the entire opening of the enclosure. Swing-frame grinders shall also be exhausted in the same manner as provided for cradles. (See fig. D-57.3)
| Dia. D inches (cm) | Exhaust E | Volume Exhausted at 4,500 ft/min ft 3 /min | Note | |
|---|---|---|---|---|
| Min. | Max. | No Pipes | Dia. | |
| 20 (50.8) | 1 | 4 1 ⁄ 4 (10.795) | 500 | When one-half or more of the disc can be hooded, use exhaust ducts as shown at the left. |
| Over 20 (50.8) | 30 (76.2) | 2 | 4 (10.16) | 780 |
| Over 30 (76.2) | 72 (182.88) | 2 | 6 (15.24) | 1,770 |
| Over 53 (134.62) | 72 (182.88) | 2 | 8 (20.32) | 3,140 |
| 20 (50.8) | 2 | 4 (10.16) | 780 | When no hood can be used over disc, use exhaust ducts as shown at left. |
| Over 20 (50.8) | 20 (50.8) | 2 | 4 (10.16) | 780 |
| Over 30 (76.2) | 30 (76.2) | 2 | 5 1 ⁄ 2 (13.97) | 1,480 |
| Over 53 (134.62) | 53 (134.62) | 4 | 6 (15.24) | 3,530 |
| 72 (182.88) | 5 | 7 (17.78) | 6,010 | |
| Entry loss = 1.0 slot velocity pressure + 0.5 branch velocity pressure. | ||||
| Minimum slot velocity = 2,000 ft/min— 1 ⁄ 2 -inch (1.27 cm) slot width. |
| Wheel dimension, inches (centimeters) | Exhaust outlet, inches (centimeters) E | Volume of air at 4,500 ft/min | ||
|---|---|---|---|---|
| Diameter | Width, Max | |||
| Min= d | Max= D | |||
| 9 (22.86) | 1 1 ⁄ 2 (3.81) | 3 | 220 | |
| Over 9 (22.86) | 16 (40.64) | 2 (5.08) | 4 | 390 |
| Over 16 (40.64) | 19 (48.26) | 3 (7.62) | 4 1 ⁄ 2 | 500 |
| Over 19 (48.26) | 24 (60.96) | 4 (10.16) | 5 | 610 |
| Over 24 (60.96) | 30 (76.2) | 5 (12.7) | 6 | 880 |
| Over 30 (76.2) | 36 (91.44) | 6 (15.24) | 7 | 1,200 |
| Entry loss = 0.45 velocity pressure for tapered takeoff 0.65 velocity pressure for straight takeoff. |
| Wheel dimension, inches (centimeters) | Exhaust outlet, inches E | Volume of air at 4,500 ft/min | ||
|---|---|---|---|---|
| Diameter | Width, Max | |||
| Min= d | Max= D | |||
| 9 (22.86) | 2 (5.08) | 3 1 ⁄ 2 (3.81) | 300 | |
| Over 9 (22.86) | 16 (40.64) | 3 (5.08) | 4 | 500 |
| Over 16 (40.64) | 19 (48.26) | 4 (11.43) | 5 | 610 |
| Over 19 (48.26) | 24 (60.96) | 5 (12.7) | 5 1 ⁄ 2 | 740 |
| Over 24 (60.96) | 30 (76.2) | 6 (15.24) | 6 1 ⁄ 2 | 1.040 |
| Over 30 (76.2) | 36 (91.44) | 6 (15.24) | 7 | 1.200 |
| Entry loss = 0.15 velocity pressure for tapered takeoff; 0.65 velocity pressure for straight takeoff. |
Entry loss = 0.45 velocity pressure for tapered takeoff
| Dia D, inches (centimeters) | Exhaust E, dia. inches (cm) | Volume exhausted at 4,500 ft/min ft 3 /min | |
|---|---|---|---|
| Min. | Max. | ||
| 12 (30.48) | 3 (7.6) | 220 | |
| Over 12 (30.48) | 19 (48.26) | 4 (10.16) | 390 |
| Over 19 (48.26) | 30 (76.2) | 5 (12.7) | 610 |
| Over 30 (76.2) | 36 (91.44) | 6 (15.24) | 880 |
| Note: If grinding wheels are used for disc grinding purposes, hoods must conform to structural strength and materials as described in 9.1. | |||
| Entry loss = 0.45 velocity pressure for tapered takeoff. |
| Disc dia. inches (centimeters) | Exhaust E | Volume exhaust at 4,500 ft/min. ft 3 /min | Note | ||
|---|---|---|---|---|---|
| Min. | Max. | No Pipes | Dia. | ||
| 19 (48.26) | 1 | 5 | 610 | ||
| Over 19 (48.26) | 25 (63.5) | 1 | 6 | 880 | When width “W” permits, exhaust ducts should be as near heaviest grinding as possible. |
| Over 25 (63.5) | 30 (76.2) | 1 | 7 | 1,200 | |
| Over 30 (76.2) | 53 (134.62) | 2 | 6 | 1,770 | |
| Over 53 (134.62) | 72 (182.88) | 4 | 8 | 6,280 | |
| Entry loss = 0.45 velocity pressure for tapered takeoff. |
Entry loss = 0.45 velocity pressure for tapered takeoff
| Belt width W. inches (centimeters) | Exhaust volume. ft. 1 /min |
|---|---|
| Up to 3 (7.62) | 220 |
| 3 to 5 (7.62 to 12.7) | 300 |
| 5 to 7 (12.7 to 17.78) | 390 |
| 7 to 9 (17.78 to 22.86) | 500 |
| 9 to 11 (22.86 to 27.94) | 610 |
| 11 to 13 (27.94 to 33.02) | 740 |
| Minimum duct velocity = 4,500 ft/min branch, 3,500 ft/min main. | |
| Entry loss = 0.45 velocity pressure for tapered takeoff; 0.65 velocity pressure for straight takeoff. |
This paragraph (g), prescribes the use of exhaust hood enclosures and systems in removing dust, dirt, fumes, and gases generated through the grinding, polishing, or buffing of ferrous and nonferrous metals.
Spray-finishing operations are employment of methods wherein organic or inorganic materials are utilized in dispersed form for deposit on surfaces to be coated, treated, or cleaned. Such methods of deposit may involve either automatic, manual, or electrostatic deposition but do not include metal spraying or metallizing, dipping, flow coating, roller coating, tumbling, centrifuging, or spray washing and degreasing as conducted in self-contained washing and degreasing machines or systems.
Spray booths are defined and described in § 1926.66(a). (See sections 103, 104, and 105 of the Standard for Spray Finishing Using Flammable and Combustible Materials, NFPA No. 33-1969).
A spray room is a room in which spray-finishing operations not conducted in a spray booth are performed separately from other areas.
Minimum maintained velocity is the velocity of air movement which must be maintained in order to meet minimum specified requirements for health and safety.
Spray booths or spray rooms are to be used to enclose or confine all operations. Spray-finishing operations shall be located as provided in sections 201 through 206 of the Standard for Spray Finishing Using Flammable and Combustible Materials, NFPA No. 33-1969.
| Operating conditions for objects completely inside booth | Crossdraft, f.p.m. | Airflow velocities, f.p.m. | |
|---|---|---|---|
| Design | Range | ||
| Electrostatic and automatic airless operation contained in booth without operator | Negligible | 50 large booth | 50-75 |
| 100 small booth | 75-125 | ||
| Air-operated guns, manual or automatic | Up to 50 | 100 large booth | 75-125 |
| 150 small booth | 125-175 | ||
| Air-operated guns, manual or automatic | Up to 100 | 150 large booth | 125-175 |
| 200 small booth | 150-250 | ||
| Notes: | |||
| (1) Attention is invited to the fact that the effectiveness of the spray booth is dependent upon the relationship of the depth of the booth to its height and width. | |||
| (2) Crossdrafts can be eliminated through proper design and such design should be sought. Crossdrafts in excess of 100fpm (feet per minute) should not be permitted. | |||
| (3) Excessive air pressures result in loss of both efficiency and material waste in addition to creating a backlash that may carry overspray and fumes into adjacent work areas. | |||
| (4) Booths should be designed with velocities shown in the column headed “Design.” However, booths operating with velocities shown in the column headed “Range” are in compliance with this standard. |
Example:
To determine the lower explosive limits of the most common solvents used in spray finishing, see Table D-57.8. Column 1 gives the number of cubic feet of vapor per gallon of solvent and column 2 gives the lower explosive limit (LEL) in percentage by volume of air. Note that the quantity of solvent will be diminished by the quantity of solids and nonflammables contained in the finish.
To determine the volume of air in cubic feet necessary to dilute the vapor from 1 gallon of solvent to 25 percent of the lower explosive limit, apply the following formula:
Dilution volume required per gallon of solvent = 4 (100-LEL) (cubic feet of vapor per gallon) ÷ LEL
Using toluene as the solvent.
of toluene from Table D-57.8, column 2, is 1.4 percent.
4 (100-1.4) 30.4 ÷ 1.4 = 8,564 cubic feet.
| Solvent | Cubic feet per gallon of vapor of liquid at 70 °F (21.11 °C). | Lower explosive limit in percent by volume of air at 70 °F (21.11 °C) |
|---|---|---|
| Column 1 | Column 2 | |
| Acetone | 44.0 | 2.6 |
| Amyl Acetate (iso) | 21.6 | 1 1.0 |
| Amyl Alcohol (n) | 29.6 | 1.2 |
| Amyl Alcohol (iso) | 29.6 | 1.2 |
| Benzene | 36.8 | 1 1.4 |
| Butyl Acetate (n) | 24.8 | 1.7 |
| Butyl Alcohol (n) | 35.2 | 1.4 |
| Butyl Cellosolve | 24.8 | 1.1 |
| Cellosolve | 33.6 | 1.8 |
| Cellosolve Acetate | 23.2 | 1.7 |
| Cyclohexanone | 31.2 | 1 1.1 |
| 1,1 Dichloroethylene | 42.4 | 5.9 |
| 1,2 Dichloroethylene | 42.4 | 9.7 |
| Ethyl Acetate | 32.8 | 2.5 |
| Ethyl Alcohol | 55.2 | 4.3 |
| Ethyl Lactate | 28.0 | 1 1.5 |
| Methyl Acetate | 40.0 | 3.1 |
| Methyl Alcohol | 80.8 | 7.3 |
| Methyl Cellosolve | 40.8 | 2.5 |
| Methyl Ethyl Ketone | 36.0 | 1.8 |
| Methyl n-Propyl Ketone | 30.4 | 1.5 |
| Naphtha (VM&P) (76°Naphtha) | 22.4 | 0.9 |
| Naphtha (100°Flash) Safety Solvent—Stoddard Solvent | 23.2 | 1.0 |
| Propyl Acetate (n) | 27.2 | 2.8 |
| Propyl Acetate (iso) | 28.0 | 1.1 |
| Propyl Alcohol (n) | 44.8 | 2.1 |
| Propyl Alcohol (iso) | 44.0 | 2.0 |
| Toluene | 30.4 | 1.4 |
| Turpentine | 20.8 | 0.8 |
| Xylene (o) | 26.4 | 1.0 |
| 1 At 212 °F (100 °C). |
Spray booths or spray rooms are to be used to enclose or confine all spray finishing operations covered by this paragraph (h). This paragraph does not apply to the spraying of the exteriors of buildings, fixed tanks, or similar structures, nor to small portable spraying apparatus not used repeatedly in the same location.
Class is determined by two factors, hazard potential designated by a letter from A to D, inclusive, and rate of gas, vapor, or mist evolution designated by a number from 1 to 4, inclusive (for example, B.3).
Note A:
c
1
TLV
1
c
2
TLV
2
c
3
TLV
3
c
N
TLV
N
Where:
c = Concentration measured at the operation in p.p.m.
| Hazard potential | Toxicity group | ||
|---|---|---|---|
| Gas or vapor (p.p.m.) | Mist (mg./m 3 ) | Flash point in degrees F. (C.) | |
| A | 0-10 | 0-0.1 | |
| B | 11-100 | 0.11-1.0 | Under 100 (37.77) |
| C | 101-500 | 1.1-10 | 100 200 (37.77-93.33) |
| D | Over 500 | Over 10 | Over 200 (93.33) |
| Rate | Liquid temperature, °F. (C.) | Degrees below boiling point | Relative evaporation 2 | Gassing 3 |
|---|---|---|---|---|
| 1 | Over 200 (93.33) | 0-20 | Fast | High. |
| 2 | 150-200 (65.55-93.33) | 21-50 | Medium | Medium. |
| 3 | 94-149 (34.44-65) | 51-100 | Slow | Low. |
| 4 | Under 94 (34.44) | Over 100 | Nil | Nil. |
| 1 In certain classes of equipment, specifically vapor degreasers, an internal condenser or vapor level thermostat is used to prevent the vapor from leaving the tank during normal operation. In such cases, rate of vapor evolution from the tank into the workroom is not dependent upon the factors listed in the table, but rather upon abnormalities of operating procedure, such as carryout of vapors from excessively fast action, dragout of liquid by entrainment in parts, contamination of solvent by water and other materials, or improper heat balance. When operating procedure is excellent, effective rate of evolution may be taken as 4. When operating procedure is average, the effective rate of evolution may be taken as 3. When operation is poor, a rate of 2 or 1 is indicated, depending upon observed conditions. | ||||
| 2 Relative evaporation rate is determined according to the methods described by A. K. Doolittle in Industrial and Engineering Chemistry, vol. 27, p. 1169, (3) where time for 100-percent evaporation is as follows: Fast: 0-3 hours; Medium: 3-12 hours; Slow: 12-50 hours; Nil: more than 50 hours. | ||||
| 3 Gassing means the formation by chemical or electrochemical action of minute bubbles of gas under the surface of the liquid in the tank and is generally limited to aqueous solutions. |
Where ventilation is used to control potential exposures to workers as defined in paragraph (i)(2)(iii) of this section, it shall be adequate to reduce the concentration of the air contaminant to the degree that a hazard to the worker does not exist. Methods of ventilation are discussed in American National Standard Fundamentals Governing the Design and Operation of Local Exhaust Systems, Z9.2-1960.
| Class | Enclosing hood | Lateral exhaust 1 | Canopy hood 2 | ||
|---|---|---|---|---|---|
| One open side | Two open sides | Three open sides | Four open sides | ||
| B-1 and A-2 | 100 | 150 | 150 | Do not use | Do not use |
| A-3 2 , B-1, B-2, and C-1 | 75 | 100 | 100 | 125 | 175 |
| A-3, C-2, and D-1 3 | 65 | 90 | 75 | 100 | 150 |
| B-4 2 , C-3, and D-2 3 | 50 | 75 | 50 | 75 | 125 |
| A-4, C-4, D-3 3 , and D-4 4 | |||||
| 1 See Table D-57.12 for computation of ventilation rate. | |||||
| 2 Do not use canopy hood for Hazard Potential A processes. | |||||
| 3 Where complete control of hot water is desired, design as next highest class. | |||||
| 4 General room ventilation required. |
| Required minimum control velocity, f.p.m. (from Table D-57.11) | C.f.m. per sq. ft. to maintain required minimum velocities at following ratios (tank width (W)/tank length (L)). 1 2 | ||||
|---|---|---|---|---|---|
| 0.0-0.09 | 0.1-0.24 | 0.25-0.49 | 0.5-0.99 | 1.0-2.0 | |
| Hood along one side or two parallel sides of tank when one hood is against a wall or baffle. 2 | |||||
| Also for a manifold along tank centerline. 3 | |||||
| 50 | 50 | 60 | 75 | 90 | 100 |
| 75 | 75 | 90 | 110 | 130 | 150 |
| 100 | 100 | 125 | 150 | 175 | 200 |
| 150 | 150 | 190 | 225 | 260 | 300 |
| Hood along one side or two parallel sides of free standing tank not against wall or baffle. | |||||
| 50 | 75 | 90 | 100 | 110 | 125 |
| 75 | 110 | 130 | 150 | 170 | 190 |
| 100 | 150 | 175 | 200 | 225 | 250 |
| 150 | 225 | 260 | 300 | 340 | 375 |
| 1 It is not practicable to ventilate across the long dimension of a tank whose ratio W / L exceeds 2.0. | |||||
| It is undesirable to do so when W / L exceeds 1.0. For circular tanks with lateral exhaust along up to 1 ⁄ 2 the circumference, use W / L = 1.0; for over one-half the circumference use W / L = 0.5. | |||||
| 2 Baffle is a vertical plate the same length as the tank, and with the top of the plate as high as the tank is wide. If the exhaust hood is on the side of a tank against a building wall or close to it, it is perfectly baffled. | |||||
| 3 Use W /2 as tank width in computing when manifold is along centerline, or when hoods are used on two parallel sides of a tank. | |||||
| Tank Width ( W ) means the effective width over which the hood must pull air to operate (for example, where the hood face is set back from the edge of the tank, this set back must be added in measuring tank width). The surface area of tanks can frequently be reduced and better control obtained (particularly on conveyorized systems) by using covers extending from the upper edges of the slots toward the center of the tank. |
Wherever spraying or other mechanical means are used to disperse a liquid above an open-surface tank, control must be provided for the airborne spray. Such operations shall be enclosed as completely as possible. The inward air velocity into the enclosure shall be sufficient to prevent the discharge of spray into the workroom. Mechanical baffles may be used to help prevent the discharge of spray. Spray painting operations are covered by paragraph (h) of this section.
Dikes or other arrangements shall be provided to prevent the possibility of intermixing of cyanide and acid in the event of tank rupture.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35099, June 30, 1993; 61 FR 9250, Mar. 3, 1996; 63 FR 1295, Jan. 8, 1998]
The requirements applicable to construction work under this section are identical to those set forth at 29 CFR 1910.501 subpart U.
[86 FR 61555, Nov. 5, 2021]
[61 FR 31431, June 20, 1996]
spill/emergency cleanup at construction sites; and
For the purpose of this section, the following definitions shall apply:
Action level means a concentration of airborne MDA of 5 ppb as an eight (8)-hour time-weighted average.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person specifically authorized by the employer whose duties require the person to enter a regulated area, or any person entering such an area as a designated representative of employees for the purpose of exercising the right to observe monitoring and measuring procedures under paragraph (p) of this section, or any other person authorized by the Act or regulations issued under the Act.
Container means any barrel, bottle, can, cylinder, drum, reaction vessel, storage tank, commercial packaging or the like, but does not include piping systems.
Decontamination area means an area outside of but as near as practical to the regulated area, consisting of an equipment storage area, wash area, and clean change area, which is used for the decontamination of workers, materials, and equipment contaminated with MDA.
Dermal exposure to MDA occurs where employees are engaged in the handling, application or use of mixtures or materials containing MDA, with any of the following non-airborne forms of MDA:
Director means the Director of the National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment which results in an unexpected and potentially hazardous release of MDA.
Employee exposure means exposure to MDA which would occur if the employee were not using respirators or protective work clothing and equipment.
Finished article containing MDA is defined as a manufactured item:
Historical monitoring data means monitoring data for construction jobs that meet the following conditions:
4,4 ′ Methylenedianiline or MDA means the chemical; 4,4′-diaminodiphenylmethane, Chemical Abstract Service Registry number 101-77-9, in the form of a vapor, liquid, or solid. The definition also includes the salts of MDA.
Regulated Areas means areas where airborne concentrations of MDA exceed or can reasonably be expected to exceed, the permissible exposure limits, or where “dermal exposure to MDA” can occur.
STEL means short term exposure limit as determined by any 15-minute sample period.
The employer shall assure that no employee is exposed to an airborne concentration of MDA in excess of ten parts per billion (10 ppb) as an 8-hour time-weighted average and a STEL of one hundred parts per billion (100 ppb).
On multi-employer worksites, an employer performing work involving the application of MDA or materials containing MDA for which establishment of one or more regulated areas is required shall inform other employers on the site of the nature of the employer's work with MDA and of the existence of, and requirements pertaining to, regulated areas.
Where there is the possibility of employee exposure to MDA due to an emergency, means shall be developed to promptly alert employees who have the potential to be directly exposed. Affected employees not engaged in correcting emergency conditions shall be evacuated immediately in the event that an emergency occurs. Means shall also be developed for alerting other employees who may be exposed as a result of the emergency.
Each employer who has a workplace or work operation covered by this standard shall perform initial monitoring to determine accurately the airborne concentrations of MDA to which employees may be exposed unless:
The employer shall institute the exposure monitoring required under paragraphs (f)(2) and (f)(3) of this section when there has been a change in production process, chemicals present, control equipment, personnel, or work practices which may result in new or additional exposures to MDA, or when the employer has any reason to suspect a change which may result in new or additional exposures.
Monitoring shall be accurate, to a confidence level of 95 percent, to within plus or minus 25 percent for airborne concentrations of MDA.
The employer shall make routine inspections of employee hands, face and forearms potentially exposed to MDA. Other potential dermal exposures reported by the employee must be referred to the appropriate medical personnel for observation. If the employer determines that the employee has been exposed to MDA the employer shall:
The employer shall establish regulated areas where airborne concentrations of MDA exceed or can reasonably be expected to exceed, the permissible exposure limits.
Where employees are subject to “dermal exposure to MDA” the employer shall establish those work areas as regulated areas.
Regulated areas shall be demarcated from the rest of the workplace in a manner that minimizes the number of persons potentially exposed.
Access to regulated areas shall be limited to authorized persons.
Each person entering a regulated area shall be supplied with, and required to use, the appropriate personal protective clothing and equipment in accordance with paragraphs (i) and (j) of this section.
The employer shall ensure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in regulated areas.
For workers engaged in spray application methods, respiratory protection must be used in addition to feasible engineering controls and work practices to reduce employee exposure to or below the PELs.
Compressed air shall not be used to remove MDA, unless the compressed air is used in conjunction with an enclosed ventilation system designed to capture the dust cloud created by the compressed air.
The employer shall not use employee rotation as a means of compliance with the exposure limits prescribed in paragraph (c) of this section.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer must implement a respiratory protection program in accordance with § 1910.134 (b) through (d) (except (d)(1)(iii)), and (f) through (m), which covers each employee required by this section to use a respirator.
Where employees are subject to dermal exposure to MDA, where liquids containing MDA can be splashed into the eyes, or where airborne concentrations of MDA are in excess of the PEL, the employer shall provide, at no cost to the employee, and ensure that the employee uses, appropriate protective work clothing and equipment which prevent contact with MDA such as, but not limited to:
The employer shall ensure that change areas are equipped with separate storage facilities for protective clothing and street clothing, in accordance with 29 CFR 1910.141(e).
The equipment area shall be supplied with impermeable, labeled bags and containers for the containment and disposal of contaminated protective clothing and equipment.
The employer shall include Methylenedianiline (MDA) in the program established to comply with the Hazard Communication Standard (HCS) (§ 1910.1200). The employer shall ensure that each employee has access to labels on containers of MDA and safety data sheets, and is trained in accordance with the provisions of HCS and paragraph (l)(3) of this section. The employer shall ensure that at least the following hazards are addressed: Cancer; liver effects; and skin sensitization.
DANGER
MDA
MAY CAUSE CANCER
CAUSES DAMAGE TO THE LIVER
RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING MAY BE REQUIRED IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
MDA
MAY CAUSE CANCER
LIVER TOXIN
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE CLOTHING MAY BE REQUIRED TO BE WORN IN THIS AREA
DANGER
CONTAINS MDA
MAY CAUSE CANCER
CAUSES DAMAGE TO THE LIVER
DANGER
CONTAINS MDA
MAY CAUSE CANCER
LIVER TOXIN
DANGER
CONTAINS MDA
CONTAINS MATERIALS WHICH MAY CAUSE CANCER
LIVER TOXIN
If the employer determines that the employee has been exposed to a potentially hazardous amount of MDA in an emergency situation under paragraph (e) of this section, the employer shall provide medical examinations in accordance with paragraphs (n)(3) (i) and (ii) of this section. If the results of liver function testing indicate an abnormality, the employee shall be removed in accordance with paragraph (n)(9) of this section. Repeat liver function tests shall be conducted on the advice of the physician. If the results of the tests are normal, tests must be repeated two to three weeks from the initial testing. If the results of the second set of tests are normal and on the advice of the physician, no additional testing is required.
Where the employee develops signs and symptoms associated with exposure to MDA, the employer shall provide the employee with an additional medical examination including liver function tests. Repeat liver function tests shall be conducted on the advice of the physician. If the results of the tests are normal, tests must be repeated two to three weeks from the initial testing. If the results of the second set of tests are normal and on the advice of the physician, no additional testing is required.
The employee shall be removed from work environments in which exposure to MDA is at or above the action level or where dermal exposure to MDA may occur, following an initial examination (paragraph (n)(2) of this section), periodic examinations (paragraph (n)(3) of this section), an emergency situation (paragraph (n)(4) of this section), or an additional examination (paragraph (n)(5) of this section) in the following circumstances:
Where the physician review mechanism used pursuant to the medical surveillance provisions of this section, has not yet resulted in a final medical determination with respect to an employee, the employer shall act as follows:
The employer may remove the employee from exposure to MDA, provide special protective measures to the employee, or place limitations upon the employee, consistent with the medical findings, determinations, or recommendations of the physician who has reviewed the employee's health status.
The employer may return the employee to his or her former job status, and end any special protective measures provided to the employee, consistent with the medical findings, determinations, or recommendations of any of the physicians who have reviewed the employee's health status, with two exceptions:
The employer shall provide to an employee up to six (6) months of medical removal protection benefits on each occasion that an employee is removed from exposure to MDA or otherwise limited pursuant to this section.
For the purposes of this section, the requirement that an employer provide medical removal protection benefits means that the employer shall maintain the earnings, seniority, and other employment rights and benefits of an employee as though the employee had not been removed from normal exposure to MDA or otherwise limited.
If a removed employee files a claim for workers' compensation payments for a MDA-related disability, then the employer shall continue to provide medical removal protection benefits pending disposition of the claim. To the extent that an award is made to the employee for earnings lost during the period of removal, the employer's medical removal protection obligation shall be reduced by such amount. The employer shall receive no credit for workers' compensation payments received by the employee for treatment-related expenses.
The employer's obligation to provide medical removal protection benefits to a removed employee shall be reduced to the extent that the employee receives compensation for earnings lost during the period of removal either from a publicly or employer-funded compensation program, or receives income from employment with any employer made possible by virtue of the employee's removal.
Where an employer, although not required by this section to do so, removes an employee from exposure to MDA or otherwise places limitations on an employee due to the effects of MDA exposure on the employee's medical condition, the employer shall provide medical removal protection benefits to the employee equal to that required by paragraph (n)(9)(v) of this section.
The employer shall maintain all employee training records for one (1) year beyond the last date of employment.
The employer shall comply with the requirements concerning transfer of records set forth in 29 CFR 1910.1020(h).
The employer shall provide affected employees, or their designated representatives, an opportunity to observe the measuring or monitoring of employee exposure to MDA conducted pursuant to paragraph (f) of this section.
When observation of the measuring or monitoring of employee exposure to MDA requires entry into areas where the use of protective clothing and equipment or respirators is required, the employer shall provide the observer with personal protective clothing and equipment or respirators required to be worn by employees working in the area, assure the use of such clothing and equipment or respirators, and require the observer to comply with all other applicable safety and health procedures.
The information contained in appendices A, B, C, and D of this section is not intended, by itself, to create any additional obligations not otherwise imposed by this standard nor detract from any existing obligation.
Appendix A to § 1926.60—Substance Data Sheet, for 4-4′ Methylenedianiline
Appendix B to § 1926.60—Substance Technical Guidelines, MDA
Appendix C to § 1926.60—Medical Surveillance Guidelines for MDA
Appendix D to § 1926.60—Sampling and Analytical Methods for MDA Monitoring and Measurement Procedures
[57 FR 35681, Aug. 10, 1992, as amended at 57 FR 49649, Nov. 3, 1992; 61 FR 5510, Feb. 13, 1996; 61 FR 31431, June 20, 1996; 63 FR 1296, Jan. 8, 1998; 69 FR 70373, Dec. 6, 2004; 70 FR 1143, Jan. 5, 2005; 71 FR 16674, Apr. 3, 2006; 71 FR 50191, Aug. 24, 2006; 73 FR 75588, Dec. 12, 2008; 76 FR 33611, June 8, 2011; 77 FR 17889, Mar. 26, 2012]
[61 FR 31432, June 20, 1996]
This section applies to all construction work where an employee may be occupationally exposed to lead. All construction work excluded from coverage in the general industry standard for lead by 29 CFR 1910.1025(a)(2) is covered by this standard. Construction work is defined as work for construction, alteration and/or repair, including painting and decorating. It includes but is not limited to the following:
Action level means employee exposure, without regard to the use of respirators, to an airborne concentration of lead of 30 micrograms per cubic meter of air (30 µg/m 3 ) calculated as an 8-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Competent person means one who is capable of identifying existing and predictable lead hazards in the surroundings or working conditions and who has authorization to take prompt corrective measures to eliminate them.
Director means the Director, National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Lead means metallic lead, all inorganic lead compounds, and organic lead soaps. Excluded from this definition are all other organic lead compounds.
This section means this standard.
3
Manual demolition of structures (e.g, dry wall), manual scraping, manual sanding, heat gun applications, and power tool cleaning with dust collection systems;
rivet busting; power tool cleaning without dust collection systems; cleanup activities where dry expendable abrasives are used; and abrasive blasting enclosure movement and removal.
Where a determination, conducted under paragraphs (d) (1), (2), and (3) of this section is made that no employee is exposed to airborne concentrations of lead at or above the action level the employer shall make a written record of such determination. The record shall include at least the information specified in paragraph (d)(3)(i) of this section and shall also include the date of determination, location within the worksite, and the name of each employee monitored.
Whenever there has been a change of equipment, process, control, personnel or a new task has been initiated that may result in additional employees being exposed to lead at or above the action level or may result in employees already exposed at or above the action level being exposed above the PEL, the employer shall conduct additional monitoring in accordance with this paragraph.
The employer shall use a method of monitoring and analysis which has an accuracy (to a confidence level of 95%) of not less than plus or minus 25 percent for airborne concentrations of lead equal to or greater than 30 µg/m 3.
The employer shall implement engineering and work practice controls, including administrative controls, to reduce and maintain employee exposure to lead to or below the permissible exposure limit to the extent that such controls are feasible. Wherever all feasible engineering and work practices controls that can be instituted are not sufficient to reduce employee exposure to or below the permissible exposure limit prescribed in paragraph (c) of this section, the employer shall nonetheless use them to reduce employee exposure to the lowest feasible level and shall supplement them by the use of respiratory protection that complies with the requirements of paragraph (f) of this section.
When ventilation is used to control lead exposure, the employer shall evaluate the mechanical performance of the system in controlling exposure as necessary to maintain its effectiveness.
If administrative controls are used as a means of reducing employees TWA exposure to lead, the employer shall establish and implement a job rotation schedule which includes:
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
Where an employee is exposed to lead above the PEL without regard to the use of respirators, where employees are exposed to lead compounds which may cause skin or eye irritation (e.g. lead arsenate, lead azide), and as interim protection for employees performing tasks as specified in paragraph (d)(2) of this section, the employer shall provide at no cost to the employee and assure that the employee uses appropriate protective work clothing and equipment that prevents contamination of the employee and the employee's garments such as, but not limited to:
DANGER: CLOTHING AND EQUIPMENT CONTAMINATED WITH LEAD. MAY DAMAGE FERTILITY OR THE UNBORN CHILD. CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM. DO NOT EAT, DRINK OR SMOKE WHEN HANDLING. DO NOT REMOVE DUST BY BLOWING OR SHAKING. DISPOSE OF LEAD CONTAMINATED WASH WATER IN ACCORDANCE WITH APPLICABLE LOCAL, STATE, OR FEDERAL REGULATIONS.
Caution: Clothing contaminated with lead. Do not remove dust by blowing or shaking. Dispose of lead contaminated wash water in accordance with applicable local, state, or federal regulations.
The employer shall make available biological monitoring in the form of blood sampling and analysis for lead and zinc protoporphyrin levels to each employee covered under paragraphs (j)(1)(i) and (ii) of this section on the following schedule:
Whenever the results of a blood lead level test indicate that an employee's blood lead level is at or above the numerical criterion for medical removal under paragraph (k)(1)(i) of this section, the employer shall provide a second (follow-up) blood sampling test within two weeks after the employer receives the results of the first blood sampling test.
Blood lead level sampling and analysis provided pursuant to this section shall have an accuracy (to a confidence level of 95 percent) within plus or minus 15 percent or 6 µg/dl, whichever is greater, and shall be conducted by a laboratory approved by OSHA.
The employer shall make available medical examinations and consultations to each employee covered under paragraph (j)(1)(ii) of this section on the following schedule:
The content of medical examinations made available pursuant to paragraph (j)(3)(i)(B)-
The employer and an employee or authorized employee representative may agree upon the use of any alternate physician determination mechanism in lieu of the multiple physician review mechanism provided by paragraph (j)(3)(iii) of this section so long as the alternate mechanism is as expeditious and protective as the requirements contained in this paragraph.
The employer shall remove an employee from work having an exposure to lead at or above the action level on each occasion that a periodic and a follow-up blood sampling test conducted pursuant to this section indicate that the employee's blood lead level is at or above 50 µg/dl; and,
Where the multiple physician review mechanism, or alternate medical determination mechanism used pursuant to the medical surveillance provisions of this section, has not yet resulted in a final medical determination with respect to an employee, the employer shall act as follows:
The employer may remove the employee from exposure to lead, provide special protective measures to the employee, or place limitations upon the employee, consistent with the medical findings, determinations, or recommendations of any of the physicians who have reviewed the employee's health status.
The employer may return the employee to his or her former job status, end any special protective measures provided to the employee, and remove any limitations placed upon the employee, consistent with the medical findings, determinations, or recommendations of any of the physicians who have reviewed the employee's health status, with two exceptions.
The employer shall provide an employee up to eighteen (18) months of medical removal protection benefits on each occasion that an employee is removed from exposure to lead or otherwise limited pursuant to this section.
For the purposes of this section, the requirement that an employer provide medical removal protection benefits means that, as long as the job the employee was removed from continues, the employer shall maintain the total normal earnings, seniority and other employment rights and benefits of an employee, including the employee's right to his or her former job status as though the employee had not been medically removed from the employee's job or otherwise medically limited.
If a removed employee files a claim for workers' compensation payments for a lead-related disability, then the employer shall continue to provide medical removal protection benefits pending disposition of the claim. To the extent that an award is made to the employee for earnings lost during the period of removal, the employer's medical removal protection obligation shall be reduced by such amount. The employer shall receive no credit for workers' compensation payments received by the employee for treatment- related expenses.
The employer's obligation to provide medical removal protection benefits to a removed employee shall be reduced to the extent that the employee receives compensation for earnings lost during the period of removal either from a publicly or employer-funded compensation program, or receives income from employment with another employer made possible by virtue of the employee's removal.
Where an employer, although not required by this section to do so, removes an employee from exposure to lead or otherwise places limitations on an employee due to the effects of lead exposure on the employee's medical condition, the employer shall provide medical removal protection benefits to the employee equal to that required by paragraph (k)(2) (i) and (ii) of this section.
The employer shall include lead in the program established to comply with the Hazard Communication Standard (HCS) (§ 1910.1200). The employer shall ensure that each employee has access to labels on containers of lead and safety data sheets, and is trained in accordance with the provisions of HCS and paragraph (l) of this section. The employer shall ensure that at least the following hazards are addressed:
The employer shall assure that each employee is trained in the following:
DANGER
LEAD WORK AREA
MAY DAMAGE FERTILITY OR THE UNBORN CHILD
CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM
DO NOT EAT, DRINK OR SMOKE IN THIS AREA
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
The employer shall make available upon request all records required to be maintained by paragraph (n) of this section to affected employees, former employees, and their designated representatives, and to the Assistant Secretary and the Director for examination and copying.
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to lead conducted pursuant to paragraph (d) of this section.
The information contained in the appendices to this section is not intended by itself, to create any additional obligations not otherwise imposed by this standard nor detract from any existing obligation.
Appendix A to § 1926.62—Substance Data Sheet for Occupational Exposure to Lead
I. Substance Identification
A. Substance: Pure lead (Pb) is a heavy metal at room temperature and pressure and is a basic chemical element. It can combine with various other substances to form numerous lead compounds.
B. Compounds covered by the standard: The word lead when used in this interim final standard means elemental lead, all inorganic lead compounds and a class of organic lead compounds called lead soaps. This standard does not apply to other organic lead compounds.
C. Uses: Exposure to lead occurs in several different occupations in the construction industry, including demolition or salvage of structures where lead or lead-containing materials are present; removal or encapsulation of lead-containing materials, new construction, alteration, repair, or renovation of structures that contain lead or materials containing lead; installation of products containing lead. In addition, there are construction related activities where exposure to lead may occur, including transportation, disposal, storage, or containment of lead or materials containing lead on construction sites, and maintenance operations associated with construction activities.
D. Permissible exposure: The permissible exposure limit (PEL) set by the standard is 50 micrograms of lead per cubic meter of air (50 µg/m 3 ), averaged over an 8-hour workday.
E. Action level: The interim final standard establishes an action level of 30 micrograms of lead per cubic meter of air (30 µg/m 3 ), averaged over an 8-hour workday. The action level triggers several ancillary provisions of the standard such as exposure monitoring, medical surveillance, and training.
II. Health Hazard Data
A. Ways in which lead enters your body. When absorbed into your body in certain doses, lead is a toxic substance. The object of the lead standard is to prevent absorption of harmful quantities of lead. The standard is intended to protect you not only from the immediate toxic effects of lead, but also from the serious toxic effects that may not become apparent until years of exposure have passed. Lead can be absorbed into your body by inhalation (breathing) and ingestion (eating). Lead (except for certain organic lead compounds not covered by the standard, such as tetraethyl lead) is not absorbed through your skin. When lead is scattered in the air as a dust, fume respiratory tract. Inhalation of airborne lead is generally the most important source of occupational lead absorption. You can also absorb lead through your digestive system if lead gets into your mouth and is swallowed. If you handle food, cigarettes, chewing tobacco, or make-up which have lead on them or handle them with hands contaminated with lead, this will contribute to ingestion. A significant portion of the lead that you inhale or ingest gets into your blood stream. Once in your blood stream, lead is circulated throughout your body and stored in various organs and body tissues. Some of this lead is quickly filtered out of your body and excreted, but some remains in the blood and other tissues. As exposure to lead continues, the amount stored in your body will increase if you are absorbing more lead than your body is excreting. Even though you may not be aware of any immediate symptoms of disease, this lead stored in your tissues can be slowly causing irreversible damage, first to individual cells, then to your organs and whole body systems.
B. Effects of overexposure to lead —
Lead is a potent, systemic poison that serves no known useful function once absorbed by your body. Taken in large enough doses, lead can kill you in a matter of days. A condition affecting the brain called acute encephalopathy may arise which develops quickly to seizures, coma, and death from cardiorespiratory arrest. A short term dose of lead can lead to acute encephalopathy. Short term occupational exposures of this magnitude are highly unusual, but not impossible. Similar forms of encephalopathy may, however, arise from extended, chronic exposure to lower doses of lead. There is no sharp dividing line between rapidly developing acute effects of lead, and chronic effects which take longer to acquire. Lead adversely affects numerous body systems, and causes forms of health impairment and disease which arise after periods of exposure as short as days or as long as several years.
Chronic overexposure to lead may result in severe damage to your blood-forming, nervous, urinary and reproductive systems. Some common symptoms of chronic overexposure include loss of appetite, metallic taste in the mouth, anxiety, constipation, nausea, pallor, excessive tiredness, weakness, insomnia, headache, nervous irritability, muscle and joint pain or soreness, fine tremors, numbness, dizziness, hyperactivity and colic. In lead colic there may be severe abdominal pain. Damage to the central nervous system in general and the brain (encephalopathy) in particular is one of the most severe forms of lead poisoning. The most severe, often fatal, form of encephalopathy may be preceded by vomiting, a feeling of dullness progressing to drowsiness and stupor, poor memory, restlessness, irritability, tremor, and convulsions. It may arise suddenly with the onset of seizures, followed by coma, and death. There is a tendency for muscular weakness to develop at the same time. This weakness may progress to paralysis often observed as a characteristic “wrist drop” or “foot drop” and is a manifestation of a disease to the nervous system called peripheral neuropathy. Chronic overexposure to lead also results in kidney disease with few, if any, symptoms appearing until extensive and most likely permanent kidney damage has occurred. Routine laboratory tests reveal the presence of this kidney disease only after about two-thirds of kidney function is lost. When overt symptoms of urinary dysfunction arise, it is often too late to correct or prevent worsening conditions, and progression to kidney dialysis or death is possible. Chronic overexposure to lead impairs the reproductive systems of both men and women. Overexposure to lead may result in decreased sex drive, impotence and sterility in men. Lead can alter the structure of sperm cells raising the risk of birth defects. There is evidence of miscarriage and stillbirth in women whose husbands were exposed to lead or who were exposed to lead themselves. Lead exposure also may result in decreased fertility, and abnormal menstrual cycles in women. The course of pregnancy may be adversely affected by exposure to lead since lead crosses the placental barrier and poses risks to developing fetuses. Children born of parents either one of whom were exposed to excess lead levels are more likely to have birth defects, mental retardation, behavioral disorders or die during the first year of childhood. Overexposure to lead also disrupts the blood-forming system resulting in decreased hemoglobin (the substance in the blood that carries oxygen to the cells) and ultimately anemia. Anemia is characterized by weakness, pallor and fatigability as a result of decreased oxygen carrying capacity in the blood.
Prevention of adverse health effects for most workers from exposure to lead throughout a working lifetime requires that a worker's blood lead level (BLL, also expressed as PbB) be maintained at or below forty micrograms per deciliter of whole blood (40 µg/dl). The blood lead levels of workers (both male and female workers) who intend to have children should be maintained below 30 µg/dl to minimize adverse reproductive health effects to the parents and to the developing fetus. The measurement of your blood lead level (BLL) is the most useful indicator of the amount of lead being absorbed by your body. Blood lead levels are most often reported in units of milligrams (mg) or micrograms (µg) of lead (1 mg = 1000 µg) per 100 grams (100g), 100 milliliters (100 ml) or deciliter (dl) of blood. These three units are essentially the same. Sometime BLLs are expressed in the form of mg% or µg%. This is a shorthand notation for 100g, 100 ml, or dl. (References to BLL measurements in this standard are expressed in the form of µg/dl.)
BLL measurements show the amount of lead circulating in your blood stream, but do not give any information about the amount of lead stored in your various tissues. BLL measurements merely show current absorption of lead, not the effect that lead is having on your body or the effects that past lead exposure may have already caused. Past research into lead-related diseases, however, has focused heavily on associations between BLLs and various diseases. As a result, your BLL is an important indicator of the likelihood that you will gradually acquire a lead-related health impairment or disease.
Once your blood lead level climbs above 40 µg/dl, your risk of disease increases. There is a wide variability of individual response to lead, thus it is difficult to say that a particular BLL in a given person will cause a particular effect. Studies have associated fatal encephalopathy with BLLs as low as 150 µg/dl. Other studies have shown other forms of diseases in some workers with BLLs well below 80 µg/dl. Your BLL is a crucial indicator of the risks to your health, but one other factor is also extremely important. This factor is the length of time you have had elevated BLLs. The longer you have an elevated BLL, the greater the risk that large quantities of lead are being gradually stored in your organs and tissues (body burden). The greater your overall body burden, the greater the chances of substantial permanent damage. The best way to prevent all forms of lead-related impairments and diseases—both short term and long term—is to maintain your BLL below 40 µg/dl. The provisions of the standard are designed with this end in mind.
Your employer has prime responsibility to assure that the provisions of the standard are complied with both by the company and by individual workers. You, as a worker, however, also have a responsibility to assist your employer in complying with the standard. You can play a key role in protecting your own health by learning about the lead hazards and their control, learning what the standard requires, following the standard where it governs your own actions, and seeing that your employer complies with provisions governing his or her actions.
You should immediately notify your employer if you develop signs or symptoms associated with lead poisoning or if you desire medical advice concerning the effects of current or past exposure to lead or your ability to have a healthy child. You should also notify your employer if you have difficulty breathing during a respirator fit test or while wearing a respirator. In each of these cases, your employer must make available to you appropriate medical examinations or consultations. These must be provided at no cost to you and at a reasonable time and place. The standard contains a procedure whereby you can obtain a second opinion by a physician of your choice if your employer selected the initial physician.
Appendix B to § 1926.62—Employee Standard Summary
This appendix summarizes key provisions of the interim final standard for lead in construction that you as a worker should become familiar with.
I. Permissible Exposure Limit (PEL)—Paragraph (C)
The standard sets a permissible exposure limit (PEL) of 50 micrograms of lead per cubic meter of air (50 µg/m 3 ), averaged over an 8-hour workday which is referred to as a time-weighted average (TWA). This is the highest level of lead in air to which you may be permissibly exposed over an 8-hour workday. However, since this is an 8-hour average, short exposures above the PEL are permitted so long as for each 8-hour work day your average exposure does not exceed this level. This interim final standard, however, takes into account the fact that your daily exposure to lead can extend beyond a typical 8-hour workday as the result of overtime or other alterations in your work schedule. To deal with this situation, the standard contains a formula which reduces your permissible exposure when you are exposed more than 8 hours. For example, if you are exposed to lead for 10 hours a day, the maximum permitted average exposure would be 40 µg/m 3.
II. Exposure Assessment—Paragraph (D)
If lead is present in your workplace in any quantity, your employer is required to make an initial determination of whether any employee's exposure to lead exceeds the action level (30 µg/m 3 averaged over an 8-hour day). Employee exposure is that exposure which would occur if the employee were not using a respirator. This initial determination requires your employer to monitor workers' exposures unless he or she has objective data which can demonstrate conclusively that no employee will be exposed to lead in excess of the action level. Where objective data is used in lieu of actual monitoring the employer must establish and maintain an accurate record, documenting its relevancy in assessing exposure levels for current job conditions. If such objective data is available, the employer need proceed no further on employee exposure assessment until such time that conditions have changed and the determination is no longer valid.
Objective data may be compiled from various sources, e.g., insurance companies and trade associations and information from suppliers or exposure data collected from similar operations. Objective data may also comprise previously-collected sampling data including area monitoring. If it cannot be determined through using objective data that worker exposure is less than the action level, your employer must conduct monitoring or must rely on relevant previous personal sampling, if available. Where monitoring is required for the initial determination, it may be limited to a representative number of employees who are reasonably expected to have the highest exposure levels. If your employer has conducted appropriate air sampling for lead in the past 12 months, he or she may use these results, provided they are applicable to the same employee tasks and exposure conditions and meet the requirements for accuracy as specified in the standard. As with objective data, if such results are relied upon for the initial determination, your employer must establish and maintain a record as to the relevancy of such data to current job conditions.
If there have been any employee complaints of symptoms which may be attributable to exposure to lead or if there is any other information or observations which would indicate employee exposure to lead, this must also be considered as part of the initial determination.
If this initial determination shows that a reasonable possibility exists that any employee may be exposed, without regard to respirators, over the action level, your employer must set up an air monitoring program to determine the exposure level representative of each employee exposed to lead at your workplace. In carrying out this air monitoring program, your employer is not required to monitor the exposure of every employee, but he or she must monitor a representative number of employees and job types. Enough sampling must be done to enable each employee's exposure level to be reasonably represent full shift exposure. In addition, these air samples must be taken under conditions which represent each employee's regular, daily exposure to lead. Sampling performed in the past 12 months may be used to determine exposures above the action level if such sampling was conducted during work activities essentially similar to present work conditions.
The standard lists certain tasks which may likely result in exposures to lead in excess of the PEL and, in some cases, exposures in excess of 50 times the PEL. If you are performing any of these tasks, your employer must provide you with appropriate respiratory protection, protective clothing and equipment, change areas, hand washing facilities, biological monitoring, and training until such time that an exposure assessment is conducted which demonstrates that your exposure level is below the PEL.
If you are exposed to lead and air sampling is performed, your employer is required to notify you in writing within 5 working days of the air monitoring results which represent your exposure. If the results indicate that your exposure exceeds the PEL (without regard to your use of a respirator), then your employer must also notify you of this in writing, and provide you with a description of the corrective action that has been taken or will be taken to reduce your exposure.
Your exposure must be rechecked by monitoring, at least every six months if your exposure is at or over the action level but below the PEL. Your employer may discontinue monitoring for you if 2 consecutive measurements, taken at least 7 days apart, are at or below the action level. Air monitoring must be repeated every 3 months if you are exposed over the PEL. Your employer must continue monitoring for you at this frequency until 2 consecutive measurements, taken at least 7 days apart, are below the PEL but above the action level, at which time your employer must repeat monitoring of your exposure every six months and may discontinue monitoring only after your exposure drops to or below the action level. However, whenever there is a change of equipment, process, control, or personnel or a new type of job is added at your workplace which may result in new or additional exposure to lead, your employer must perform additional monitoring.
III. Methods of Compliance—Paragraph (E)
Your employer is required to assure that no employee is exposed to lead in excess of the PEL as an 8-hour TWA. The interim final standard for lead in construction requires employers to institute engineering and work practice controls including administrative controls to the extent feasible to reduce employee exposure to lead. Where such controls are feasible but not adequate to reduce exposures below the PEL they must be used nonetheless to reduce exposures to the lowest level that can be accomplished by these means and then supplemented with appropriate respiratory protection.
Your employer is required to develop and implement a written compliance program prior to the commencement of any job where employee exposures may reach the PEL as an 8-hour TWA. The interim final standard identifies the various elements that must be included in the plan. For example, employers are required to include a description of operations in which lead is emitted, detailing other relevant information about the operation such as the type of equipment used, the type of material involved, employee job responsibilities, operating procedures and maintenance practices. In addition, your employer's compliance plan must specify the means that will be used to achieve compliance and, where engineering controls are required, include any engineering plans or studies that have been used to select the control methods. If administrative controls involving job rotation are used to reduce employee exposure to lead, the job rotation schedule must be included in the compliance plan. The plan must also detail the type of protective clothing and equipment, including respirators, housekeeping and hygiene practices that will be used to protect you from the adverse effects of exposure to lead.
The written compliance program must be made available, upon request, to affected employees and their designated representatives, the Assistant Secretary and the Director.
Finally, the plan must be reviewed and updated at least every 6 months to assure it reflects the current status in exposure control.
IV. Respiratory Protection—Paragraph (F)
Your employer is required to provide and assure your use of respirators when your exposure to lead is not controlled below the PEL by other means. The employer must pay the cost of the respirator. Whenever you request one, your employer is also required to provide you a respirator even if your air exposure level is not above the PEL. You might desire a respirator when, for example, you have received medical advice that your lead absorption should be decreased. Or, you may intend to have children in the near future, and want to reduce the level of lead in your body to minimize adverse reproductive effects. While respirators are the least satisfactory means of controlling your exposure, they are capable of providing significant protection if properly chosen, fitted, worn, cleaned, maintained, and replaced when they stop providing adequate protection.
Your employer is required to select your respirator according to the requirements of 29 CFR 1926.62(f)(3), including the requirements referenced in 29 CFR 1910.134(d)(3)(i)(A) of this chapter. Any respirator chosen must be approved by NIOSH under the provisions of 42 CFR part 84. These respirator selection references will enable your employer to choose a type of respirator that will give you a proper amount of protection based on your airborne lead exposure. Your employer may select a type of respirator that provides greater protection than that required by the standard; that is, one recommended for a higher concentration of lead than is present in your workplace. For example, a powered air-purifying respirator (PAPR) is much more protective than a typical negative pressure respirator, and may also be more comfortable to wear. A PAPR has a filter, cartridge, or canister to clean the air, and a power source that continuously blows filtered air into your breathing zone. Your employer might make a PAPR available to you to ease the burden of having to wear a respirator for long periods of time. The standard provides that you can obtain a PAPR upon request.
Your employer must also start a Respiratory Protection Program. This program must include written procedures for the proper selection, use, cleaning, storage, and maintenance of respirators.
Your employer must ensure that your respirator facepiece fits properly. Proper fit of a respirator facepiece is critical to your protection from airborne lead. Obtaining a proper fit on each employee may require your employer to make available several different types of respirator masks. To ensure that your respirator fits properly and that facepiece leakage is minimal, your employer must give you either a qualitative or quantitative fit test as specified in appendix A of the Respiratory Protection standard located at 29 CFR 1910.134.
You must also receive from your employer proper training in the use of respirators. Your employer is required to teach you how to wear a respirator, to know why it is needed, and to understand its limitations.
The standard provides that if your respirator uses filter elements, you must be given an opportunity to change the filter elements whenever an increase in breathing resistance is detected. You also must be permitted to periodically leave your work area to wash your face and respirator facepiece whenever necessary to prevent skin irritation. If you ever have difficulty in breathing during a fit test or while using a respirator, your employer must make a medical examination available to you to determine whether you can safely wear a respirator. The result of this examination may be to give you a positive pressure respirator (which reduces breathing resistance) or to provide alternative means of protection.
V. Protective Work Clothing and Equipment—Paragraph (G)
If you are exposed to lead above the PEL as an 8-hour TWA, without regard to your use of a respirator, or if you are exposed to lead compounds such as lead arsenate or lead azide which can cause skin and eye irritation, your employer must provide you with protective work clothing and equipment appropriate for the hazard. If work clothing is provided, it must be provided in a clean and dry condition at least weekly, and daily if your airborne exposure to lead is greater than 200 µg/m 3. Appropriate protective work clothing and equipment can include coveralls or similar full-body work clothing, gloves, hats, shoes or disposable shoe coverlets, and face shields or vented goggles. Your employer is required to provide all such equipment at no cost to you. In addition, your employer is responsible for providing repairs and replacement as necessary, and also is responsible for the cleaning, laundering or disposal of protective clothing and equipment.
The interim final standard requires that your employer assure that you follow good work practices when you are working in areas where your exposure to lead may exceed the PEL. With respect to protective clothing and equipment, where appropriate, the following procedures should be observed prior to beginning work:
1. Change into work clothing and shoe covers in the clean section of the designated changing areas;
2. Use work garments of appropriate protective gear, including respirators before entering the work area; and
3. Store any clothing not worn under protective clothing in the designated changing area.
Workers should follow these procedures upon leaving the work area:
1. HEPA vacuum heavily contaminated protective work clothing while it is still being worn. At no time may lead be removed from protective clothing by any means which result in uncontrolled dispersal of lead into the air;
2. Remove shoe covers and leave them in the work area;
3. Remove protective clothing and gear in the dirty area of the designated changing area. Remove protective coveralls by carefully rolling down the garment to reduce exposure to dust.
4. Remove respirators last; and
5. Wash hands and face.
Workers should follow these procedures upon finishing work for the day (in addition to procedures described above):
1. Where applicable, place disposal coveralls and shoe covers with the abatement waste;
2. Contaminated clothing which is to be cleaned, laundered or disposed of must be placed in closed containers in the change room.
3. Clean protective gear, including respirators, according to standard procedures;
4. Wash hands and face again. If showers are available, take a shower and wash hair. If shower facilities are not available at the work site, shower immediately at home and wash hair.
VI. Housekeeping—Paragraph (H)
Your employer must establish a housekeeping program sufficient to maintain all surfaces as free as practicable of accumulations of lead dust. Vacuuming is the preferred method of meeting this requirement, and the use of compressed air to clean floors and other surfaces is generally prohibited unless removal with compressed air is done in conjunction with ventilation systems designed to contain dispersal of the lead dust. Dry or wet sweeping, shoveling, or brushing may not be used except where vacuuming or other equally effective methods have been tried and do not work. Vacuums must be used equipped with a special filter called a high-efficiency particulate air (HEPA) filter and emptied in a manner which minimizes the reentry of lead into the workplace.
VII. Hygiene Facilities and Practices—Paragraph (I)
The standard requires that hand washing facilities be provided where occupational exposure to lead occurs. In addition, change areas, showers (where feasible), and lunchrooms or eating areas are to be made available to workers exposed to lead above the PEL. Your employer must assure that except in these facilities, food and beverage is not present or consumed, tobacco products are not present or used, and cosmetics are not applied, where airborne exposures are above the PEL. Change rooms provided by your employer must be equipped with separate storage facilities for your protective clothing and equipment and street clothes to avoid cross-contamination. After showering, no required protective clothing or equipment worn during the shift may be worn home. It is important that contaminated clothing or equipment be removed in change areas and not be worn home or you will extend your exposure and expose your family since lead from your clothing can accumulate in your house, car, etc.
Lunchrooms or eating areas may not be entered with protective clothing or equipment unless surface dust has been removed by vacuuming, downdraft booth, or other cleaning method. Finally, workers exposed above the PEL must wash both their hands and faces prior to eating, drinking, smoking or applying cosmetics.
All of the facilities and hygiene practices just discussed are essential to minimize additional sources of lead absorption from inhalation or ingestion of lead that may accumulate on you, your clothes, or your possessions. Strict compliance with these provisions can virtually eliminate several sources of lead exposure which significantly contribute to excessive lead absorption.
VIII. Medical Surveillance—Paragraph (J)
The medical surveillance program is part of the standard's comprehensive approach to the prevention of lead-related disease. Its purpose is to supplement the main thrust of the standard which is aimed at minimizing airborne concentrations of lead and sources of ingestion. Only medical surveillance can determine if the other provisions of the standard have affectively protected you as an individual. Compliance with the standard's provision will protect most workers from the adverse effects of lead exposure, but may not be satisfactory to protect individual workers (1) who have high body burdens of lead acquired over past years, (2) who have additional uncontrolled sources of non-occupational lead exposure, (3) who exhibit unusual variations in lead absorption rates, or (4) who have specific non-work related medical conditions which could be aggravated by lead exposure (e.g., renal disease, anemia). In addition, control systems may fail, or hygiene and respirator programs may be inadequate. Periodic medical surveillance of individual workers will help detect those failures. Medical surveillance will also be important to protect your reproductive ability-regardless of whether you are a man or woman.
All medical surveillance required by the interim final standard must be performed by or under the supervision of a licensed physician. The employer must provide required medical surveillance without cost to employees and at a reasonable time and place. The standard's medical surveillance program has two parts—periodic biological monitoring and medical examinations. Your employer's obligation to offer you medical surveillance is triggered by the results of the air monitoring program. Full medical surveillance must be made available to all employees who are or may be exposed to lead in excess of the action level for more than 30 days a year and whose blood lead level exceeds 40 µg/dl. Initial medical surveillance consisting of blood sampling and analysis for lead and zinc protoporphyrin must be provided to all employees exposed at any time (1 day) above the action level.
Biological monitoring under the standard must be provided at least every 2 months for the first 6 months and every 6 months thereafter until your blood lead level is below 40 µg/dl. A zinc protoporphyrin (ZPP) test is a very useful blood test which measures an adverse metabolic effect of lead on your body and is therefore an indicator of lead toxicity.
If your BLL exceeds 40 µg/dl the monitoring frequency must be increased from every 6 months to at least every 2 months and not reduced until two consecutive BLLs indicate a blood lead level below 40 µg/dl. Each time your BLL is determined to be over 40 µg/dl, your employer must notify you of this in writing within five working days of his or her receipt of the test results. The employer must also inform you that the standard requires temporary medical removal with economic protection when your BLL exceeds 50 µg/dl. (See Discussion of Medical Removal Protection-Paragraph (k).) Anytime your BLL exceeds 50 µg/dl your employer must make available to you within two weeks of receipt of these test results a second follow-up BLL test to confirm your BLL. If the two tests both exceed 50 µg/dl, and you are temporarily removed, then your employer must make successive BLL tests available to you on a monthly basis during the period of your removal.
Medical examinations beyond the initial one must be made available on an annual basis if your blood lead level exceeds 40 µg/dl at any time during the preceding year and you are being exposed above the airborne action level of 30 µg/m 3 for 30 or more days per year. The initial examination will provide information to establish a baseline to which subsequent data can be compared.
An initial medical examination to consist of blood sampling and analysis for lead and zinc protoporphyrin must also be made available (prior to assignment) for each employee being assigned for the first time to an area where the airborne concentration of lead equals or exceeds the action level at any time. In addition, a medical examination or consultation must be made available as soon as possible if you notify your employer that you are experiencing signs or symptoms commonly associated with lead poisoning or that you have difficulty breathing while wearing a respirator or during a respirator fit test. You must also be provided a medical examination or consultation if you notify your employer that you desire medical advice concerning the effects of current or past exposure to lead on your ability to procreate a healthy child.
Finally, appropriate follow-up medical examinations or consultations may also be provided for employees who have been temporarily removed from exposure under the medical removal protection provisions of the standard. (See Part IX, below.)
The standard specifies the minimum content of pre-assignment and annual medical examinations. The content of other types of medical examinations and consultations is left up to the sound discretion of the examining physician. Pre-assignment and annual medical examinations must include (1) a detailed work history and medical history; (2) a thorough physical examination, including an evaluation of your pulmonary status if you will be required to use a respirator; (3) a blood pressure measurement; and (4) a series of laboratory tests designed to check your blood chemistry and your kidney function. In addition, at any time upon your request, a laboratory evaluation of male fertility will be made (microscopic examination of a sperm sample), or a pregnancy test will be given.
The standard does not require that you participate in any of the medical procedures, tests, etc. which your employer is required to make available to you. Medical surveillance can, however, play a very important role in protecting your health. You are strongly encouraged, therefore, to participate in a meaningful fashion. The standard contains a multiple physician review mechanism which will give you a chance to have a physician of your choice directly participate in the medical surveillance program. If you are dissatisfied with an examination by a physician chosen by your employer, you can select a second physician to conduct an independent analysis. The two doctors would attempt to resolve any differences of opinion, and select a third physician to resolve any firm dispute. Generally your employer will choose the physician who conducts medical surveillance under the lead standard-unless you and your employer can agree on the choice of a physician or physicians. Some companies and unions have agreed in advance, for example, to use certain independent medical laboratories or panels of physicians. Any of these arrangements are acceptable so long as required medical surveillance is made available to workers.
The standard requires your employer to provide certain information to a physician to aid in his or her examination of you. This information includes (1) the standard and its appendices, (2) a description of your duties as they relate to occupational lead exposure, (3) your exposure level or anticipated exposure level, (4) a description of any personal protective equipment you wear, (5) prior blood lead level results, and (6) prior written medical opinions concerning you that the employer has. After a medical examination or consultation the physician must prepare a written report which must contain (1) the physician's opinion as to whether you have any medical condition which places you at increased risk of material impairment to health from exposure to lead, (2) any recommended special protective measures to be provided to you, (3) any blood lead level determinations, and (4) any recommended limitation on your use of respirators. This last element must include a determination of whether you can wear a powered air purifying respirator (PAPR) if you are found unable to wear a negative pressure respirator.
The medical surveillance program of the interim lead standard may at some point in time serve to notify certain workers that they have acquired a disease or other adverse medical condition as a result of occupational lead exposure. If this is true, these workers might have legal rights to compensation from public agencies, their employers, firms that supply hazardous products to their employers, or other persons. Some states have laws, including worker compensation laws, that disallow a worker who learns of a job-related health impairment to sue, unless the worker sues within a short period of time after learning of the impairment. (This period of time may be a matter of months or years.) An attorney can be consulted about these possibilities. It should be stressed that OSHA is in no way trying to either encourage or discourage claims or lawsuits. However, since results of the standard's medical surveillance program can significantly affect the legal remedies of a worker who has acquired a job-related disease or impairment, it is proper for OSHA to make you aware of this.
The medical surveillance section of the standard also contains provisions dealing with chelation. Chelation is the use of certain drugs (administered in pill form or injected into the body) to reduce the amount of lead absorbed in body tissues. Experience accumulated by the medical and scientific communities has largely confirmed the effectiveness of this type of therapy for the treatment of very severe lead poisoning. On the other hand, it has also been established that there can be a long list of extremely harmful side effects associated with the use of chelating agents. The medical community has balanced the advantages and disadvantages resulting from the use of chelating agents in various circumstances and has established when the use of these agents is acceptable. The standard includes these accepted limitations due to a history of abuse of chelation therapy by some lead companies. The most widely used chelating agents are calcium disodium EDTA, (Ca Na2 EDTA), Calcium Disodium Versenate (Versenate), and d-penicillamine (pencillamine or Cupramine).
The standard prohibits “prophylactic chelation” of any employee by any person the employer retains, supervises or controls. Prophylactic chelation is the routine use of chelating or similarly acting drugs to prevent elevated blood levels in workers who are occupationally exposed to lead, or the use of these drugs to routinely lower blood lead levels to predesignated concentrations believed to be “safe”. It should be emphasized that where an employer takes a worker who has no symptoms of lead poisoning and has chelation carried out by a physician (either inside or outside of a hospital) solely to reduce the worker's blood lead level, that will generally be considered prophylactic chelation. The use of a hospital and a physician does not mean that prophylactic chelation is not being performed. Routine chelation to prevent increased or reduce current blood lead levels is unacceptable whatever the setting.
The standard allows the use of “therapeutic” or “diagnostic” chelation if administered under the supervision of a licensed physician in a clinical setting with thorough and appropriate medical monitoring. Therapeutic chelation responds to severe lead poisoning where there are marked symptoms. Diagnostic chelation involved giving a patient a dose of the drug then collecting all urine excreted for some period of time as an aid to the diagnosis of lead poisoning.
In cases where the examining physician determines that chelation is appropriate, you must be notified in writing of this fact before such treatment. This will inform you of a potentially harmful treatment, and allow you to obtain a second opinion.
IX. Medical Removal Protection—Paragraph (K)
Excessive lead absorption subjects you to increased risk of disease. Medical removal protection (MRP) is a means of protecting you when, for whatever reasons, other methods, such as engineering controls, work practices, and respirators, have failed to provide the protection you need. MRP involves the temporary removal of a worker from his or her regular job to a place of significantly lower exposure without any loss of earnings, seniority, or other employment rights or benefits. The purpose of this program is to cease further lead absorption and allow your body to naturally excrete lead which has previously been absorbed. Temporary medical removal can result from an elevated blood lead level, or a medical opinion. For up to 18 months, or for as long as the job the employee was removed from lasts, protection is provided as a result of either form of removal. The vast majority of removed workers, however, will return to their former jobs long before this eighteen month period expires.
You may also be removed from exposure even if your blood lead level is below 50 µg/dl if a final medical determination indicates that you temporarily need reduced lead exposure for medical reasons. If the physician who is implementing your employers medical program makes a final written opinion recommending your removal or other special protective measures, your employer must implement the physician's recommendation. If you are removed in this manner, you may only be returned when the doctor indicates that it is safe for you to do so.
The standard does not give specific instructions dealing with what an employer must do with a removed worker. Your job assignment upon removal is a matter for you, your employer and your union (if any) to work out consistent with existing procedures for job assignments. Each removal must be accomplished in a manner consistent with existing collective bargaining relationships. Your employer is given broad discretion to implement temporary removals so long as no attempt is made to override existing agreements. Similarly, a removed worker is provided no right to veto an employer's choice which satisfies the standard.
In most cases, employers will likely transfer removed employees to other jobs with sufficiently low lead exposure. Alternatively, a worker's hours may be reduced so that the time weighted average exposure is reduced, or he or she may be temporarily laid off if no other alternative is feasible.
In all of these situation, MRP benefits must be provided during the period of removal—i.e., you continue to receive the same earnings, seniority, and other rights and benefits you would have had if you had not been removed. Earnings includes more than just your base wage; it includes overtime, shift differentials, incentives, and other compensation you would have earned if you had not been removed. During the period of removal you must also be provided with appropriate follow-up medical surveillance. If you were removed because your blood lead level was too high, you must be provided with a monthly blood test. If a medical opinion caused your removal, you must be provided medical tests or examinations that the doctor believes to be appropriate. If you do not participate in this follow up medical surveillance, you may lose your eligibility for MRP benefits.
When you are medically eligible to return to your former job, your employer must return you to your “former job status.” This means that you are entitled to the position, wages, benefits, etc., you would have had if you had not been removed. If you would still be in your old job if no removal had occurred that is where you go back. If not, you are returned consistent with whatever job assignment discretion your employer would have had if no removal had occurred. MRP only seeks to maintain your rights, not expand them or diminish them.
If you are removed under MRP and you are also eligible for worker compensation or other compensation for lost wages, your employer's MRP benefits obligation is reduced by the amount that you actually receive from these other sources. This is also true if you obtain other employment during the time you are laid off with MRP benefits.
The standard also covers situations where an employer voluntarily removes a worker from exposure to lead due to the effects of lead on the employee's medical condition, even though the standard does not require removal. In these situations MRP benefits must still be provided as though the standard required removal. Finally, it is important to note that in all cases where removal is required, respirators cannot be used as a substitute. Respirators may be used before removal becomes necessary, but not as an alternative to a transfer to a low exposure job, or to a lay-off with MRP benefits.
X. Employee Information and Training—Paragraph (L)
Your employer is required to provide an information and training program for all employees exposed to lead above the action level or who may suffer skin or eye irritation from lead compounds such as lead arsenate or lead azide. The program must train these employees regarding the specific hazards associated with their work environment, protective measures which can be taken, including the contents of any compliance plan in effect, the danger of lead to their bodies (including their reproductive systems), and their rights under the standard. All employees must be trained prior to initial assignment to areas where there is a possibility of exposure over the action level.
This training program must also be provided at least annually thereafter unless further exposure above the action level will not occur.
XI. Signs—Paragraph (M)
The standard requires that the following warning sign be posted in work areas when the exposure to lead is above the PEL:
DANGER
LEAD WORK AREA
MAY DAMAGE FERTILITY OR THE UNBORN CHILD
CAUSES DAMAGE TO THE CENTRAL NERVOUS SYSTEM
DO NOT EAT, DRINK OR SMOKE IN THIS AREA
Prior to June 1, 2016, employers may use the following legend in lieu of that specified above:
WARNING
LEAD WORK AREA
POISON
NO SMOKING OR EATING
XII. Recordkeeping—Paragraph (N)
Your employer is required to keep all records of exposure monitoring for airborne lead. These records must include the name and job classification of employees measured, details of the sampling and analytical techniques, the results of this sampling, and the type of respiratory protection being worn by the person sampled. Such records are to be retained for at least 30 years. Your employer is also required to keep all records of biological monitoring and medical examination results. These records must include the names of the employees, the physician's written opinion, and a copy of the results of the examination. Medical records must be preserved and maintained for the duration of employment plus 30 years. However, if the employee's duration of employment is less than one year, the employer need not retain that employee's medical records beyond the period of employment if they are provided to the employee upon termination of employment.
Recordkeeping is also required if you are temporarily removed from your job under the medical removal protection program. This record must include your name, the date of your removal and return, how the removal was or is being accomplished, and whether or not the reason for the removal was an elevated blood lead level. Your employer is required to keep each medical removal record only for as long as the duration of an employee's employment.
The standard requires that if you request to see or copy environmental monitoring, blood lead level monitoring, or medical removal records, they must be made available to you or to a representative that you authorize. Your union also has access to these records. Medical records other than BLL's must also be provided upon request to you, to your physician or to any other person whom you may specifically designate. Your union does not have access to your personal medical records unless you authorize their access.
XIII. Observation of Monitoring—Paragraph (O)
When air monitoring for lead is performed at your workplace as required by this standard, your employer must allow you or someone you designate to act as an observer of the monitoring. Observers are entitled to an explanation of the measurement procedure, and to record the results obtained. Since results will not normally be available at the time of the monitoring, observers are entitled to record or receive the results of the monitoring when returned by the laboratory. Your employer is required to provide the observer with any personal protective devices required to be worn by employees working in the area that is being monitored. The employer must require the observer to wear all such equipment and to comply with all other applicable safety and health procedures.
XIV. For Additional Information
A. A copy of the interim standard for lead in construction can be obtained free of charge by calling or writing the OSHA Office of Publications, room N-3101, United States Department of Labor, Washington, DC 20210: Telephone (202) 219-4667.
B. Additional information about the standard, its enforcement, and your employer's compliance can be obtained from the nearest OSHA Area Office listed in your telephone directory under United States Government/Department of Labor.
Appendix C to § 1926.62—Medical Surveillance Guidelines
Introduction
The primary purpose of the Occupational Safety and Health Act of 1970 is to assure, so far as possible, safe and healthful working conditions for every working man and woman. The interim final occupational health standard for lead in construction is designed to protect workers exposed to inorganic lead including metallic lead, all inorganic lead compounds and organic lead soaps.
Under this interim final standard occupational exposure to inorganic lead is to be limited to 50 µg/m 3 (micrograms per cubic meter) based on an 8 hour time-weighted average (TWA). This permissible exposure limit (PEL) must be achieved through a combination of engineering, work practice and administrative controls to the extent feasible. Where these controls are in place but are found not to reduce employee exposures to or below the PEL, they must be used nonetheless, and supplemented with respirators to meet the 50 µg/m 3 exposure limit.
The standard also provides for a program of biological monitoring for employees exposed to lead above the action level at any time, and additional medical surveillance for all employees exposed to levels of inorganic lead above 30 µg/m 3 (TWA) for more than 30 days per year and whose BLL exceeds 40 µg/dl.
The purpose of this document is to outline the medical surveillance provisions of the interim standard for inorganic lead in construction, and to provide further information to the physician regarding the examination and evaluation of workers exposed to inorganic lead.
Section 1 provides a detailed description of the monitoring procedure including the required frequency of blood testing for exposed workers, provisions for medical removal protection (MRP), the recommended right of the employee to a second medical opinion, and notification and recordkeeping requirements of the employer. A discussion of the requirements for respirator use and respirator monitoring and OSHA's position on prophylactic chelation therapy are also included in this section.
Section 2 discusses the toxic effects and clinical manifestations of lead poisoning and effects of lead intoxication on enzymatic pathways in heme synthesis. The adverse effects on both male and female reproductive capacity and on the fetus are also discussed.
Section 3 outlines the recommended medical evaluation of the worker exposed to inorganic lead, including details of the medical history, physical examination, and recommended laboratory tests, which are based on the toxic effects of lead as discussed in Section 2.
Section 4 provides detailed information concerning the laboratory tests available for the monitoring of exposed workers. Included also is a discussion of the relative value of each test and the limitations and precautions which are necessary in the interpretation of the laboratory results.
I. Medical Surveillance and Monitoring Requirements for Workers Exposed to Inorganic Lead
Under the interim final standard for inorganic lead in the construction industry, initial medical surveillance consisting of biological monitoring to include blood lead and ZPP level determination shall be provided to employees exposed to lead at or above the action level on any one day. In addition, a program of biological monitoring is to be made available to all employees exposed above the action level at any time and additional medical surveillance is to be made available to all employees exposed to lead above 30 µg/m 3 TWA for more than 30 days each year and whose BLL exceeds 40 µg/dl. This program consists of periodic blood sampling and medical evaluation to be performed on a schedule which is defined by previous laboratory results, worker complaints or concerns, and the clinical assessment of the examining physician.
Under this program, the blood lead level (BLL) of all employees who are exposed to lead above 30 µg/m 3 for more than 30 days per year or whose blood lead is above 40 µg/dl but exposed for no more than 30 days per year is to be determined at least every two months for the first six months of exposure and every six months thereafter. The frequency is increased to every two months for employees whose last blood lead level was 40 µg/dl or above. For employees who are removed from exposure to lead due to an elevated blood lead, a new blood lead level must be measured monthly. A zinc protoporphyrin (ZPP) measurement is strongly recommended on each occasion that a blood lead level measurement is made.
An annual medical examination and consultation performed under the guidelines discussed in Section 3 is to be made available to each employee exposed above 30 µg/m 3 for more than 30 days per year for whom a blood test conducted at any time during the preceding 12 months indicated a blood lead level at or above 40 µg/dl. Also, an examination is to be given to all employees prior to their assignment to an area in which airborne lead concentrations reach or exceed the 30 µg/m 3 for more than 30 days per year. In addition, a medical examination must be provided as soon as possible after notification by an employee that the employee has developed signs or symptoms commonly associated with lead intoxication, that the employee desires medical advice regarding lead exposure and the ability to procreate a healthy child, or that the employee has demonstrated difficulty in breathing during a respirator fitting test or during respirator use. An examination is also to be made available to each employee removed from exposure to lead due to a risk of sustaining material impairment to health, or otherwise limited or specially protected pursuant to medical recommendations.
Results of biological monitoring or the recommendations of an examining physician may necessitate removal of an employee from further lead exposure pursuant to the standard's medical removal protection (MRP) program. The object of the MRP program is to provide temporary medical removal to workers either with substantially elevated blood lead levels or otherwise at risk of sustaining material health impairment from continued substantial exposure to lead.
Under the standard's ultimate worker removal criteria, a worker is to be removed from any work having an eight hour TWA exposure to lead of 30 µg/m 3 when his or her blood lead level reaches 50 µg/dl and is confirmed by a second follow-up blood lead level performed within two weeks after the employer receives the results of the first blood sampling test. Return of the employee to his or her job status depends on a worker's blood lead level declining to 40 µg/dl.
As part of the interim standard, the employer is required to notify in writing each employee whose blood lead level exceeds 40 µg/dl. In addition each such employee is to be informed that the standard requires medical removal with MRP benefits, discussed below, when an employee's blood lead level exceeds the above defined limit.
In addition to the above blood lead level criterion, temporary worker removal may also take place as a result of medical determinations and recommendations. Written medical opinions must be prepared after each examination pursuant to the standard. If the examining physician includes a medical finding, determination or opinion that the employee has a medical condition which places the employee at increased risk of material health impairment from exposure to lead, then the employee must be removed from exposure to lead at or above 30 µg/m 3. Alternatively, if the examining physician recommends special protective measures for an employee (e.g., use of a powered air purifying respirator) or recommends limitations on an employee's exposure to lead, then the employer must implement these recommendations.
Recommendations may be more stringent than the specific provisions of the standard. The examining physician, therefore, is given broad flexibility to tailor special protective procedures to the needs of individual employees. This flexibility extends to the evaluation and management of pregnant workers and male and female workers who are planning to raise children. Based on the history, physical examination, and laboratory studies, the physician might recommend special protective measures or medical removal for an employee who is pregnant or who is planning to conceive a child when, in the physician's judgment, continued exposure to lead at the current job would pose a significant risk. The return of the employee to his or her former job status, or the removal of special protections or limitations, depends upon the examining physician determining that the employee is no longer at increased risk of material impairment or that special measures are no longer needed.
During the period of any form of special protection or removal, the employer must maintain the worker's earnings, seniority, and other employment rights and benefits (as though the worker had not been removed) for a period of up to 18 months or for as long as the job the employee was removed from lasts if less than 18 months. This economic protection will maximize meaningful worker participation in the medical surveillance program, and is appropriate as part of the employer's overall obligation to provide a safe and healthful workplace. The provisions of MRP benefits during the employee's removal period may, however, be conditioned upon participation in medical surveillance.
The lead standard provides for a multiple physician review in cases where the employee wishes a second opinion concerning potential lead poisoning or toxicity. If an employee wishes a second opinion, he or she can make an appointment with a physician of his or her choice. This second physician will review the findings, recommendations or determinations of the first physician and conduct any examinations, consultations or tests deemed necessary in an attempt to make a final medical determination. If the first and second physicians do not agree in their assessment they must try to resolve their differences. If they cannot reach an agreement then they must designate a third physician to resolve the dispute.
The employer must provide examining and consulting physicians with the following specific information: A copy of the lead regulations and all appendices, a description of the employee's duties as related to exposure, the exposure level or anticipated level to lead and any other toxic substances (if applicable), a description of personal protective equipment used, blood lead levels, and all prior written medical opinions regarding the employee in the employer's possession or control. The employer must also obtain from the physician and provide the employee with a written medical opinion containing blood lead levels, the physicians's opinion as to whether the employee is at risk of material impairment to health, any recommended protective measures for the employee if further exposure is permitted, as well as any recommended limitations upon an employee's use of respirators.
Employers must instruct each physician not to reveal to the employer in writing or in any other way his or her findings, laboratory results, or diagnoses which are felt to be unrelated to occupational lead exposure. They must also instruct each physician to advise the employee of any occupationally or non-occupationally related medical condition requiring further treatment or evaluation.
The standard provides for the use of respirators where engineering and other primary controls are not effective. However, the use of respirator protection shall not be used in lieu of temporary medical removal due to elevated blood lead levels or findings that an employee is at risk of material health impairment. This is based on the numerous inadequacies of respirators including skin rash where the facepiece makes contact with the skin, unacceptable stress to breathing in some workers with underlying cardiopulmonary impairment, difficulty in providing adequate fit, the tendency for respirators to create additional hazards by interfering with vision, hearing, and mobility, and the difficulties of assuring the maximum effectiveness of a complicated work practice program involving respirators. Respirators do, however, serve a useful function where engineering and work practice controls are inadequate by providing supplementary, interim, or short-term protection, provided they are properly selected for the environment in which the employee will be working, properly fitted to the employee, maintained and cleaned periodically, and worn by the employee when required.
In its interim final standard on occupational exposure to inorganic lead in the construction industry, OSHA has prohibited prophylactic chelation. Diagnostic and therapeutic chelation are permitted only under the supervision of a licensed physician with appropriate medical monitoring in an acceptable clinical setting. The decision to initiate chelation therapy must be made on an individual basis and take into account the severity of symptoms felt to be a result of lead toxicity along with blood lead levels, ZPP levels, and other laboratory tests as appropriate. EDTA and penicillamine which are the primary chelating agents used in the therapy of occupational lead poisoning have significant potential side effects and their use must be justified on the basis of expected benefits to the worker. Unless frank and severe symptoms are present, therapeutic chelation is not recommended, given the opportunity to remove a worker from exposure and allow the body to naturally excrete accumulated lead. As a diagnostic aid, the chelation mobilization test using CA-EDTA has limited applicability. According to some investigators, the test can differentiate between lead-induced and other nephropathies. The test may also provide an estimation of the mobile fraction of the total body lead burden.
Employers are required to assure that accurate records are maintained on exposure assessment, including environmental monitoring, medical surveillance, and medical removal for each employee. Exposure assessment records must be kept for at least 30 years. Medical surveillance records must be kept for the duration of employment plus 30 years except in cases where the employment was less than one year. If duration of employment is less than one year, the employer need not retain this record beyond the term of employment if the record is provided to the employee upon termination of employment. Medical removal records also must be maintained for the duration of employment. All records required under the standard must be made available upon request to the Assistant Secretary of Labor for Occupational Safety and Health and the Director of the National Institute for Occupational Safety and Health. Employers must also make environmental and biological monitoring and medical removal records available to affected employees and to former employees or their authorized employee representatives. Employees or their specifically designated representatives have access to their entire medical surveillance records.
In addition, the standard requires that the employer inform all workers exposed to lead at or above 30 µg/m 3 of the provisions of the standard and all its appendices, the purpose and description of medical surveillance and provisions for medical removal protection if temporary removal is required. An understanding of the potential health effects of lead exposure by all exposed employees along with full understanding of their rights under the lead standard is essential for an effective monitoring program.
II. Adverse Health Effects of Inorganic Lead
Although the toxicity of lead has been known for 2,000 years, the knowledge of the complex relationship between lead exposure and human response is still being refined. Significant research into the toxic properties of lead continues throughout the world, and it should be anticipated that our understanding of thresholds of effects and margins of safety will be improved in future years. The provisions of the lead standard are founded on two prime medical judgments: First, the prevention of adverse health effects from exposure to lead throughout a working lifetime requires that worker blood lead levels be maintained at or below 40 µg/dl and second, the blood lead levels of workers, male or female, who intend to parent in the near future should be maintained below 30 µg/dl to minimize adverse reproductive health effects to the parents and developing fetus. The adverse effects of lead on reproduction are being actively researched and OSHA encourages the physician to remain abreast of recent developments in the area to best advise pregnant workers or workers planning to conceive children.
The spectrum of health effects caused by lead exposure can be subdivided into five developmental stages: Normal, physiological changes of uncertain significance, pathophysiological changes, overt symptoms (morbidity), and mortality. Within this process there are no sharp distinctions, but rather a continuum of effects. Boundaries between categories overlap due to the wide variation of individual responses and exposures in the working population. OSHA's development of the lead standard focused on pathophysiological changes as well as later stages of disease.
1. Heme Synthesis Inhibition. The earliest demonstrated effect of lead involves its ability to inhibit at least two enzymes of the heme synthesis pathway at very low blood levels. Inhibition of delta aminolevulinic acid dehydrase (ALA-D) which catalyzes the conversion of delta-aminolevulinic acid (ALA) to protoporphyrin is observed at a blood lead level below 20 µg/dl. At a blood lead level of 40 µg/dl, more than 20% of the population would have 70% inhibition of ALA-D. There is an exponential increase in ALA excretion at blood lead levels greater than 40 µg/dl.
Another enzyme, ferrochelatase, is also inhibited at low blood lead levels. Inhibition of ferrochelatase leads to increased free erythrocyte protoporphyrin (FEP) in the blood which can then bind to zinc to yield zinc protoporphyrin. At a blood lead level of 50 µg/dl or greater, nearly 100% of the population will have an increase in FEP. There is also an exponential relationship between blood lead levels greater than 40 µg/dl and the associated ZPP level, which has led to the development of the ZPP screening test for lead exposure.
While the significance of these effects is subject to debate, it is OSHA's position that these enzyme disturbances are early stages of a disease process which may eventually result in the clinical symptoms of lead poisoning. Whether or not the effects do progress to the later stages of clinical disease, disruption of these enzyme processes over a working lifetime is considered to be a material impairment of health.
One of the eventual results of lead-induced inhibition of enzymes in the heme synthesis pathway is anemia which can be asymptomatic if mild but associated with a wide array of symptoms including dizziness, fatigue, and tachycardia when more severe. Studies have indicated that lead levels as low as 50 µg/dl can be associated with a definite decreased hemoglobin, although most cases of lead-induced anemia, as well as shortened red-cell survival times, occur at lead levels exceeding 80 µg/dl. Inhibited hemoglobin synthesis is more common in chronic cases whereas shortened erythrocyte life span is more common in acute cases.
In lead-induced anemias, there is usually a reticulocytosis along with the presence of basophilic stippling, and ringed sideroblasts, although none of the above are pathognomonic for lead-induced anemia.
2. Neurological Effects. Inorganic lead has been found to have toxic effects on both the central and peripheral nervous systems. The earliest stages of lead-induced central nervous system effects first manifest themselves in the form of behavioral disturbances and central nervous system symptoms including irritability, restlessness, insomnia and other sleep disturbances, fatigue, vertigo, headache, poor memory, tremor, depression, and apathy. With more severe exposure, symptoms can progress to drowsiness, stupor, hallucinations, delirium, convulsions and coma.
The most severe and acute form of lead poisoning which usually follows ingestion or inhalation of large amounts of lead is acute encephalopathy which may arise precipitously with the onset of intractable seizures, coma, cardiorespiratory arrest, and death within 48 hours.
While there is disagreement about what exposure levels are needed to produce the earliest symptoms, most experts agree that symptoms definitely can occur at blood lead levels of 60 µg/dl whole blood and therefore recommend a 40 µg/dl maximum. The central nervous system effects frequently are not reversible following discontinued exposure or chelation therapy and when improvement does occur, it is almost always only partial.
The peripheral neuropathy resulting from lead exposure characteristically involves only motor function with minimal sensory damage and has a marked predilection for the extensor muscles of the most active extremity. The peripheral neuropathy can occur with varying degrees of severity. The earliest and mildest form which can be detected in workers with blood lead levels as low as 50 µg/dl is manifested by slowing of motor nerve conduction velocity often without clinical symptoms. With progression of the neuropathy there is development of painless extensor muscle weakness usually involving the extensor muscles of the fingers and hand in the most active upper extremity, followed in severe cases by wrist drop or, much less commonly, foot drop.
In addition to slowing of nerve conduction, electromyographical studies in patients with blood lead levels greater than 50 µg/dl have demonstrated a decrease in the number of acting motor unit potentials, an increase in the duration of motor unit potentials, and spontaneous pathological activity including fibrillations and fasciculations. Whether these effects occur at levels of 40 µg/dl is undetermined.
While the peripheral neuropathies can occasionally be reversed with therapy, again such recovery is not assured particularly in the more severe neuropathies and often improvement is only partial. The lack of reversibility is felt to be due in part to segmental demyelination.
3. Gastrointestinal. Lead may also affect the gastrointestinal system producing abdominal colic or diffuse abdominal pain, constipation, obstipation, diarrhea, anorexia, nausea and vomiting. Lead colic rarely develops at blood lead levels below 80 µg/dl.
4. Renal. Renal toxicity represents one of the most serious health effects of lead poisoning. In the early stages of disease nuclear inclusion bodies can frequently be identified in proximal renal tubular cells. Renal function remains normal and the changes in this stage are probably reversible. With more advanced disease there is progressive interstitial fibrosis and impaired renal function. Eventually extensive interstitial fibrosis ensues with sclerotic glomeruli and dilated and atrophied proximal tubules; all represent end stage kidney disease. Azotemia can be progressive, eventually resulting in frank uremia necessitating dialysis. There is occasionally associated hypertension and hyperuricemia with or without gout.
Early kidney disease is difficult to detect. The urinalysis is normal in early lead nephropathy and the blood urea nitrogen and serum creatinine increase only when two-thirds of kidney function is lost. Measurement of creatinine clearance can often detect earlier disease as can other methods of measurement of glomerular filtration rate. An abnormal Ca-EDTA mobilization test has been used to differentiate between lead-induced and other nephropathies, but this procedure is not widely accepted. A form of Fanconi syndrome with aminoaciduria, glycosuria, and hyperphosphaturia indicating severe injury to the proximal renal tubules is occasionally seen in children.
5. Reproductive effects. Exposure to lead can have serious effects on reproductive function in both males and females. In male workers exposed to lead there can be a decrease in sexual drive, impotence, decreased ability to produce healthy sperm, and sterility. Malformed sperm (teratospermia), decreased number of sperm (hypospermia), and sperm with decreased motility (asthenospermia) can all occur. Teratospermia has been noted at mean blood lead levels of 53 µg/dl and hypospermia and asthenospermia at 41 µg/dl. Furthermore, there appears to be a dose-response relationship for teratospermia in lead exposed workers.
Women exposed to lead may experience menstrual disturbances including dysmenorrhea, menorrhagia and amenorrhea. Following exposure to lead, women have a higher frequency of sterility, premature births, spontaneous miscarriages, and stillbirths.
Germ cells can be affected by lead and cause genetic damage in the egg or sperm cells before conception and result in failure to implant, miscarriage, stillbirth, or birth defects.
Infants of mothers with lead poisoning have a higher mortality during the first year and suffer from lowered birth weights, slower growth, and nervous system disorders.
Lead can pass through the placental barrier and lead levels in the mother's blood are comparable to concentrations of lead in the umbilical cord at birth. Transplacental passage becomes detectable at 12-14 weeks of gestation and increases until birth.
There is little direct data on damage to the fetus from exposure to lead but it is generally assumed that the fetus and newborn would be at least as susceptible to neurological damage as young children. Blood lead levels of 50-60 µg/dl in children can cause significant neurobehavioral impairments and there is evidence of hyperactivity at blood levels as low as 25 µg/dl. Given the overall body of literature concerning the adverse health effects of lead in children, OSHA feels that the blood lead level in children should be maintained below 30 µg/dl with a population mean of 15 µg/dl. Blood lead levels in the fetus and newborn likewise should not exceed 30 µg/dl.
Because of lead's ability to pass through the placental barrier and also because of the demonstrated adverse effects of lead on reproductive function in both the male and female as well as the risk of genetic damage of lead on both the ovum and sperm, OSHA recommends a 30 µg/dl maximum permissible blood lead level in both males and females who wish to bear children.
6. Other toxic effects. Debate and research continue on the effects of lead on the human body. Hypertension has frequently been noted in occupationally exposed individuals although it is difficult to assess whether this is due to lead's adverse effects on the kidney or if some other mechanism is involved. Vascular and electrocardiographic changes have been detected but have not been well characterized. Lead is thought to impair thyroid function and interfere with the pituitary-adrenal axis, but again these effects have not been well defined.
III. Medical Evaluation
The most important principle in evaluating a worker for any occupational disease including lead poisoning is a high index of suspicion on the part of the examining physician. As discussed in Section 2, lead can affect numerous organ systems and produce a wide array of signs and symptoms, most of which are non-specific and subtle in nature at least in the early stages of disease. Unless serious concern for lead toxicity is present, many of the early clues to diagnosis may easily be overlooked.
The crucial initial step in the medical evaluation is recognizing that a worker's employment can result in exposure to lead. The worker will frequently be able to define exposures to lead and lead containing materials but often will not volunteer this information unless specifically asked. In other situations the worker may not know of any exposures to lead but the suspicion might be raised on the part of the physician because of the industry or occupation of the worker. Potential occupational exposure to lead and its compounds occur in many occupations in the construction industry, including demolition and salvaging operations, removal or encapsulation of materials containing lead, construction, alteration, repair or renovation of structures containing lead, transportation, disposal, storage or containment of lead or lead-containing materials on construction sites, and maintenance operations associated with construction activities.
Once the possibility for lead exposure is raised, the focus can then be directed toward eliciting information from the medical history, physical exam, and finally from laboratory data to evaluate the worker for potential lead toxicity.
A complete and detailed work history is important in the initial evaluation. A listing of all previous employment with information on job description, exposure to fumes or dust, known exposures to lead or other toxic substances, a description of any personal protective equipment used, and previous medical surveillance should all be included in the worker's record. Where exposure to lead is suspected, information concerning on-the-job personal hygiene, smoking or eating habits in work areas, laundry procedures, and use of any protective clothing or respiratory protection equipment should be noted. A complete work history is essential in the medical evaluation of a worker with suspected lead toxicity, especially when long term effects such as neurotoxicity and nephrotoxicity are considered.
The medical history is also of fundamental importance and should include a listing of all past and current medical conditions, current medications including proprietary drug intake, previous surgeries and hospitalizations, allergies, smoking history, alcohol consumption, and also non-occupational lead exposures such as hobbies (hunting, riflery). Also known childhood exposures should be elicited. Any previous history of hematological, neurological, gastrointestinal, renal, psychological, gynecological, genetic, or reproductive problems should be specifically noted.
A careful and complete review of systems must be performed to assess both recognized complaints and subtle or slowly acquired symptoms which the worker might not appreciate as being significant. The review of symptoms should include the following:
1. General—weight loss, fatigue, decreased appetite.
2. Head, Eyes, Ears, Nose, Throat (HEENT)—headaches, visual disturbances or decreased visual acuity, hearing deficits or tinnitus, pigmentation of the oral mucosa, or metallic taste in mouth.
3. Cardio-pulmonary—shortness of breath, cough, chest pains, palpitations, or orthopnea.
4. Gastrointestinal—nausea, vomiting, heartburn, abdominal pain, constipation or diarrhea.
5. Neurologic—irritability, insomnia, weakness (fatigue), dizziness, loss of memory, confusion, hallucinations, incoordination, ataxia, decreased strength in hands or feet, disturbances in gait, difficulty in climbing stairs, or seizures.
6. Hematologic—pallor, easy fatigability, abnormal blood loss, melena.
7. Reproductive (male and female and spouse where relevant)—history of infertility, impotence, loss of libido, abnormal menstrual periods, history of miscarriages, stillbirths, or children with birth defects.
8. Musculo-skeletal—muscle and joint pains.
The physical examination should emphasize the neurological, gastrointestinal, and cardiovascular systems. The worker's weight and blood pressure should be recorded and the oral mucosa checked for pigmentation characteristic of a possible Burtonian or lead line on the gingiva. It should be noted, however, that the lead line may not be present even in severe lead poisoning if good oral hygiene is practiced.
The presence of pallor on skin examination may indicate an anemia which, if severe, might also be associated with a tachycardia. If an anemia is suspected, an active search for blood loss should be undertaken including potential blood loss through the gastrointestinal tract.
A complete neurological examination should include an adequate mental status evaluation including a search for behavioral and psychological disturbances, memory testing, evaluation for irritability, insomnia, hallucinations, and mental clouding. Gait and coordination should be examined along with close observation for tremor. A detailed evaluation of peripheral nerve function including careful sensory and motor function testing is warranted. Strength testing particularly of extensor muscle groups of all extremities is of fundamental importance.
Cranial nerve evaluation should also be included in the routine examination.
The abdominal examination should include auscultation for bowel sounds and abdominal bruits and palpation for organomegaly, masses, and diffuse abdominal tenderness.
Cardiovascular examination should evaluate possible early signs of congestive heart failure. Pulmonary status should be addressed particularly if respirator protection is contemplated.
As part of the medical evaluation, the interim lead standard requires the following laboratory studies:
1. Blood lead level
2. Hemoglobin and hematocrit determinations, red cell indices, and examination of the peripheral blood smear to evaluate red blood cell morphology
3. Blood urea nitrogen
4. Serum creatinine
5. Routine urinalysis with microscopic examination.
6. A zinc protoporphyrin level.
In addition to the above, the physician is authorized to order any further laboratory or other tests which he or she deems necessary in accordance with sound medical practice. The evaluation must also include pregnancy testing or laboratory evaluation of male fertility if requested by the employee. Additional tests which are probably not warranted on a routine basis but may be appropriate when blood lead and ZPP levels are equivocal include delta aminolevulinic acid and coproporphyrin concentrations in the urine, and dark-field illumination for detection of basophilic stippling in red blood cells.
If an anemia is detected further studies including a careful examination of the peripheral smear, reticulocyte count, stool for occult blood, serum iron, total iron binding capacity, bilirubin, and, if appropriate, vitamin B12 and folate may be of value in attempting to identify the cause of the anemia.
If a peripheral neuropathy is suspected, nerve conduction studies are warranted both for diagnosis and as a basis to monitor any therapy.
If renal disease is questioned, a 24 hour urine collection for creatinine clearance, protein, and electrolytes may be indicated. Elevated uric acid levels may result from lead-induced renal disease and a serum uric acid level might be performed.
An electrocardiogram and chest x-ray may be obtained as deemed appropriate.
Sophisticated and highly specialized testing should not be done routinely and where indicated should be under the direction of a specialist.
IV. Laboratory Evaluation
The blood lead level at present remains the single most important test to monitor lead exposure and is the test used in the medical surveillance program under the lead standard to guide employee medical removal. The ZPP has several advantages over the blood lead level. Because of its relatively recent development and the lack of extensive data concerning its interpretation, the ZPP currently remains an ancillary test.
This section will discuss the blood lead level and ZPP in detail and will outline their relative advantages and disadvantages. Other blood tests currently available to evaluate lead exposure will also be reviewed.
The blood lead level is a good index of current or recent lead absorption when there is no anemia present and when the worker has not taken any chelating agents. However, blood lead levels along with urinary lead levels do not necessarily indicate the total body burden of lead and are not adequate measures of past exposure. One reason for this is that lead has a high affinity for bone and up to 90% of the body's total lead is deposited there. A very important component of the total lead body burden is lead in soft tissue (liver, kidney, and brain). This fraction of the lead body burden, the biologically active lead, is not entirely reflected by blood lead levels since it is a function of the dynamics of lead absorption, distribution, deposition in bone and excretion. Following discontinuation of exposure to lead, the excess body burden is only slowly mobilized from bone and other relatively stable body stores and excreted. Consequently, a high blood lead level may only represent recent heavy exposure to lead without a significant total body excess and likewise a low blood lead level does not exclude an elevated total body burden of lead.
Also due to its correlation with recent exposures, the blood lead level may vary considerably over short time intervals.
To minimize laboratory error and erroneous results due to contamination, blood specimens must be carefully collected after thorough cleaning of the skin with appropriate methods using lead-free blood containers and analyzed by a reliable laboratory. Under the standard, samples must be analyzed in laboratories which are approved by OSHA. Analysis is to be made using atomic absorption spectrophotometry, anodic stripping voltammetry or any method which meets the accuracy requirements set forth by the standard.
The determination of lead in urine is generally considered a less reliable monitoring technique than analysis of whole blood primarily due to individual variability in urinary excretion capacity as well as the technical difficulty of obtaining accurate 24 hour urine collections. In addition, workers with renal insufficiency, whether due to lead or some other cause, may have decreased lead clearance and consequently urine lead levels may underestimate the true lead burden. Therefore, urine lead levels should not be used as a routine test.
The zinc protoporphyrin test, unlike the blood lead determination, measures an adverse metabolic effect of lead and as such is a better indicator of lead toxicity than the level of blood lead itself. The level of ZPP reflects lead absorption over the preceding 3 to 4 months, and therefore is a better indicator of lead body burden. The ZPP requires more time than the blood lead to read significantly elevated levels; the return to normal after discontinuing lead exposure is also slower. Furthermore, the ZPP test is simpler, faster, and less expensive to perform and no contamination is possible. Many investigators believe it is the most reliable means of monitoring chronic lead absorption.
Zinc protoporphyrin results from the inhibition of the enzyme ferrochelatase which catalyzes the insertion of an iron molecule into the protoporphyrin molecule, which then becomes heme. If iron is not inserted into the molecule then zinc, having a greater affinity for protoporphyrin, takes the place of the iron, forming ZPP.
An elevation in the level of circulating ZPP may occur at blood lead levels as low as 20-30 µg/dl in some workers. Once the blood lead level has reached 40 µg/dl there is more marked rise in the ZPP value from its normal range of less than 100 µg/dl100 ml. Increases in blood lead levels beyond 40 µg/100 g are associated with exponential increases in ZPP.
Whereas blood lead levels fluctuate over short time spans, ZPP levels remain relatively stable. ZPP is measured directly in red blood cells and is present for the cell's entire 120 day life-span. Therefore, the ZPP level in blood reflects the average ZPP production over the previous 3-4 months and consequently the average lead exposure during that time interval.
It is recommended that a hematocrit be determined whenever a confirmed ZPP of 50 µg/100 ml whole blood is obtained to rule out a significant underlying anemia. If the ZPP is in excess of 100 µg/100 ml and not associated with abnormal elevations in blood lead levels, the laboratory should be checked to be sure that blood leads were determined using atomic absorption spectrophotometry anodic stripping voltammetry, or any method which meets the accuracy requirements set forth by the standard by an OSHA approved laboratory which is experienced in lead level determinations. Repeat periodic blood lead studies should be obtained in all individuals with elevated ZPP levels to be certain that an associated elevated blood lead level has not been missed due to transient fluctuations in blood leads.
ZPP has a characteristic fluorescence spectrum with a peak at 594 nm which is detectable with a hematofluorimeter. The hematofluorimeter is accurate and portable and can provide on-site, instantaneous results for workers who can be frequently tested via a finger prick.
However, careful attention must be given to calibration and quality control procedures. Limited data on blood lead-ZPP correlations and the ZPP levels which are associated with the adverse health effects discussed in Section 2 are the major limitations of the test. Also it is difficult to correlate ZPP levels with environmental exposure and there is some variation of response with age and sex. Nevertheless, the ZPP promises to be an important diagnostic test for the early detection of lead toxicity and its value will increase as more data is collected regarding its relationship to other manifestations of lead poisoning.
Levels of delta-aminolevulinic acid (ALA) in the urine are also used as a measure of lead exposure. Increasing concentrations of ALA are believed to result from the inhibition of the enzyme delta-aminolevulinic acid dehydrase (ALA-D). Although the test is relatively easy to perform, inexpensive, and rapid, the disadvantages include variability in results, the necessity to collect a complete 24 hour urine sample which has a specific gravity greater than 1.010, and also the fact that ALA decomposes in the presence of light.
The pattern of porphyrin excretion in the urine can also be helpful in identifying lead intoxication. With lead poisoning, the urine concentrations of coproporphyrins I and II, porphobilinogen and uroporphyrin I rise. The most important increase, however, is that of coproporphyrin III; levels may exceed 5,000 µg/l in the urine in lead poisoned individuals, but its correlation with blood lead levels and ZPP are not as good as those of ALA. Increases in urinary porphyrins are not diagnostic of lead toxicity and may be seen in porphyria, some liver diseases, and in patients with high reticulocyte counts.
Summary. The Occupational Safety and Health Administration's interim standard for inorganic lead in the construction industry places significant emphasis on the medical surveillance of all workers exposed to levels of inorganic lead above 30 µg/m 3 TWA. The physician has a fundamental role in this surveillance program, and in the operation of the medical removal protection program.
Even with adequate worker education on the adverse health effects of lead and appropriate training in work practices, personal hygiene and other control measures, the physician has a primary responsibility for evaluating potential lead toxicity in the worker. It is only through a careful and detailed medical and work history, a complete physical examination and appropriate laboratory testing that an accurate assessment can be made. Many of the adverse health effects of lead toxicity are either irreversible or only partially reversible and therefore early detection of disease is very important.
This document outlines the medical monitoring program as defined by the occupational safety and health standard for inorganic lead. It reviews the adverse health effects of lead poisoning and describes the important elements of the history and physical examinations as they relate to these adverse effects. Finally, the appropriate laboratory testing for evaluating lead exposure and toxicity is presented.
It is hoped that this review and discussion will give the physician a better understanding of the OSHA standard with the ultimate goal of protecting the health and well-being of the worker exposed to lead under his or her care.
[58 FR 26627, May 4, 1993, as amended at 58 FR 34218, June 24, 1993; 61 FR 5510, Feb. 13, 1996; 63 FR 1296, Jan. 8, 1998; 70 FR 1143, Jan. 5, 2005; 71 FR 16674, Apr. 3, 2006; 71 FR 50191, Aug. 24, 2006; 73 FR 75588, Dec. 12, 2008; 76 FR 33611, June 8, 2011; 76 FR 80741, Dec. 27, 2011; 77 FR 17890, Mar. 26, 2012; 85 FR 8735, Feb. 18, 2020; 87 FR 38986, June 30, 2022]
For requirements regarding the process safety management of highly hazardous chemicals as it pertains to construction work, follow the requirements in 29 CFR 1910.119.
[84 FR 21576, May 14, 2019]
This section covers the following operations, unless the employer can demonstrate that the operation does not involve employee exposure or the reasonable possibility for employee exposure to safety or health hazards:
Clean-up operation means an operation where hazardous substances are removed, contained, incinerated, neutralized, stabilized, cleared-up, or in any other manner processed or handled with the ultimate goal of making the site safer for people or the environment.
Decontamination means the removal of hazardous substances from employees and their equipment to the extent necessary to preclude the occurrence of foreseeable adverse health affects.
Emergency response or responding to emergencies means a response effort by employees from outside the immediate release area or by other designated responders (i.e., mutual-aid groups, local fire departments, etc.) to an occurrence which results, or is likely to result, in an uncontrolled release of a hazardous substance. Responses to incidental releases of hazardous substances where the substance can be absorbed, neutralized, or otherwise controlled at the time of release by employees in the immediate release area, or by maintenance personnel are not considered to be emergency responses within the scope of this standard. Responses to releases of hazardous substances where there is no potential safety or health hazard (i.e., fire, explosion, or chemical exposure) are not considered to be emergency responses.
Facility means (A) any building, structure, installation, equipment, pipe or pipeline (including any pipe into a sewer or publicly owned treatment works), well, pit, pond, lagoon, impoundment, ditch, storage container, motor vehicle, rolling stock, or aircraft, or (B) any site or area where a hazardous substance has been deposited, stored, disposed of, or placed, or otherwise come to be located; but does not include any consumer product in consumer use or any water-borne vessel.
Hazardous materials response (HAZMAT) team means an organized group of employees, designated by the employer, who are expected to perform work to handle and control actual or potential leaks or spills of hazardous substances requiring possible close approach to the substance. The team members perform responses to releases or potential releases of hazardous substances for the purpose of control or stabilization of the incident. A HAZMAT team is not a fire brigade nor is a typical fire brigade a HAZMAT team. A HAZMAT team, however, may be a separate component of a fire brigade or fire department.
Hazardous substance means any substance designated or listed under paragraphs (A) through (D) of this definition, exposure to which results or may result in adverse affects on the health or safety of employees:
Department of Transportation as hazardous materials under 49 CFR 172.101 and appendices; and
Hazardous waste means—
Hazardous waste operation means any operation conducted within the scope of this standard.
Hazardous waste site or Site means any facility or location within the scope of this standard at which hazardous waste operations take place.
Health hazard means a chemical or a pathogen where acute or chronic health effects may occur in exposed employees. It also includes stress due to temperature extremes. The term health hazard includes chemicals that are classified in accordance with the Hazard Communication Standard, § 1910.1200, as posing one of the following hazardous effects: acute toxicity (any route of exposure); skin corrosion or irritation; serious eye damage or eye irritation; respiratory or skin sensitization; germ cell mutagenicity; carcinogenicity; reproductive toxicity; specific target organ toxicity (single or repeated exposure); aspiration toxicity or simple asphyxiant. ( See Appendix A to § 1910.1200—Health Hazard Criteria (Mandatory) for the criteria for determining whether a chemical is classified as a health hazard.)
IDLH or Immediately dangerous to life or health means an atmospheric concentration of any toxic, corrosive or asphyxiant substance that poses an immediate threat to life or would cause irreversible or delayed adverse health effects or would interfere with an individual's ability to escape from a dangerous atmosphere.
Oxygen deficiency means that concentration of oxygen by volume below which atmosphere supplying respiratory protection must be provided. It exists in atmospheres where the percentage of oxygen by volume is less than 19.5 percent oxygen.
Permissible exposure limit means the exposure, inhalation or dermal permissible exposure limit specified either in § 1926.55, elsewhere in subpart D, or in other pertinent sections of this part.
Published exposure level means the exposure limits published in “NIOSH Recommendations for Occupational Health Standards” dated 1986 incorporated by reference, or if none is specified, the exposure limits published in the standards specified by the American Conference of Governmental Industrial Hygienists in their publication “Threshold Limit Values and Biological Exposure Indices for 1987-88” dated 1987 incorporated by reference.
Post emergency response means that portion of an emergency response performed after the immediate threat of a release has been stabilized or eliminated and clean-up of the site has begun. If post emergency response is performed by an employer's own employees who were part of the initial emergency response, it is considered to be part of the initial response and not post emergency response. However, if a group of an employer's own employees, separate from the group providing initial response, performs the clean-up operation, then the separate group of employees would be considered to be performing post-emergency response and subject to paragraph (q)(11) of this section.
Qualified person means a person with specific training, knowledge and experience in the area for which the person has the responsibility and the authority to control.
Site safety and health supervisor (or official) means the individual located on a hazardous waste site who is responsible to the employer and has the authority and knowledge necessary to implement the site safety and health plan and verify compliance with applicable safety and health requirements.
Small quantity generator means a generator of hazardous wastes who in any calendar month generates no more than 1,000 kilograms (2,205 pounds) of hazardous waste in that month.
Uncontrolled hazardous waste site, means an area identified as an uncontrolled hazardous waste site by a governmental body, whether Federal, state, local or other where an accumulation of hazardous substances creates a threat to the health and safety of individuals or the environment or both. Some sites are found on public lands such as those created by former municipal, county or state landfills where illegal or poorly managed waste disposal has taken place. Other sites are found on private property, often belonging to generators or former generators of hazardous substance wastes. Examples of such sites include, but are not limited to, surface impoundments, landfills, dumps, and tank or drum farms. Normal operations at TSD sites are not covered by this definition.
Site excavations created during initial site preparation or during hazardous waste operations shall be shored or sloped as appropriate to prevent accidental collapse in accordance with subpart P of 29 CFR part 1926.
An employer who retains contractor or sub-contractor services for work in hazardous waste operations shall inform those contractors, sub-contractors, or their representatives of the site emergency response procedures and any potential fire, explosion, health, safety or other hazards of the hazardous waste operation that have been identified by the employer, including those identified in the employer's information program.
The written safety and health program shall be made available to any contractor or subcontractor or their representative who will be involved with the hazardous waste operation; to employees; to employee designated representatives; to OSHA personnel, and to personnel of other Federal, state, or local agencies with regulatory authority over the site.
The comprehensive workplan part of the program shall address the tasks and objectives of the site operations and the logistics and resources required to reach those tasks and objectives.
The site safety and health plan, which must be kept on site, shall address the safety and health hazards of each phase of site operation and include the requirements and procedures for employee protection.
The site safety and health plan, as a minimum, shall address the following:
The site specific safety and health plan shall provide for pre-entry briefings to be held prior to initiating any site activity, and at such other times as necessary to ensure that employees are apprised of the site safety and health plan and that this plan is being followed. The information and data obtained from site characterization and analysis work required in paragraph (c) of this section shall be used to prepare and update the site safety and health plan.
Inspections shall be conducted by the site safety and health supervisor or, in the absence of that individual, another individual who is knowledgeable in occupational safety and health, acting on behalf of the employer as necessary to determine the effectiveness of the site safety and health plan. Any deficiencies in the effectiveness of the site safety and health plan shall be corrected by the employer.
Hazardous waste sites shall be evaluated in accordance with this paragraph to identify specific site hazards and to determine the appropriate safety and health control procedures needed to protect employees from the identified hazards.
A preliminary evaluation of a site's characteristics shall be performed prior to site entry by a qualified person in order to aid in the selection of appropriate employee protection methods prior to site entry. Immediately after initial site entry, a more detailed evaluation of the site's specific characteristics shall be performed by a qualified person in order to further identify existing site hazards and to further aid in the selection of the appropriate engineering controls and personal protective equipment for the tasks to be performed.
All suspected conditions that may pose inhalation or skin absorption hazards that are immediately dangerous to life or health (IDLH), or other conditions that may cause death or serious harm, shall be identified during the preliminary survey and evaluated during the detailed survey. Examples of such hazards include, but are not limited to, confined space entry, potentially explosive or flammable situations, visible vapor clouds, or areas where biological indicators such as dead animals or vegetation are located.
The following information to the extent available shall be obtained by the employer prior to allowing employees to enter a site:
Personal protective equipment (PPE) shall be provided and used during initial site entry in accordance with the following requirements:
The following monitoring shall be conducted during initial site entry when the site evaluation produces information that shows the potential for ionizing radiation or IDLH conditions, or when the site information is not sufficient reasonably to eliminate these possible conditions:
Once the presence and concentrations of specific hazardous substances and health hazards have been established, the risks associated with these substances shall be identified. Employees who will be working on the site shall be informed of any risks that have been identified. In situations covered by the Hazard Communication Standard, 29 CFR 1926.59, training required by that standard need not be duplicated.
Any information concerning the chemical, physical, and toxicologic properties of each substance known or expected to be present on site that is available to the employer and relevant to the duties an employee is expected to perform shall be made available to the affected employees prior to the commencement of their work activities. The employer may utilize information developed for the hazard communication standard for this purpose.
Appropriate site control procedures shall be implemented to control employee exposure to hazardous substances before clean-up work begins.
A site control program for protecting employees which is part of the employer's site safety and health program required in paragraph (b) of this section shall be developed during the planning stages of a hazardous waste clean-up operation and modified as necessary as new information becomes available.
The site control program shall, as a minimum, include: A site map; site work zones; the use of a “buddy system”; site communications including alerting means for emergencies; the standard operating procedures or safe work practices; and, identification of the nearest medical assistance. Where these requirements are covered elsewhere they need not be repeated.
The training shall thoroughly cover the following:
On-site management and supervisors directly responsible for, or who supervise employees engaged in, hazardous waste operations shall receive 40 hours initial training, and three days of supervised field experience (the training may be reduced to 24 hours and one day if the only area of their responsibility is employees covered by paragraphs (e)(3)(ii) and (e)(3)(iii)) and at least eight additional hours of specialized training at the time of job assignment on such topics as, but not limited to, the employer's safety and health program and the associated employee training program, personal protective equipment program, spill containment program, and health hazard monitoring procedure and techniques.
Trainers shall be qualified to instruct employees about the subject matter that is being presented in training. Such trainers shall have satisfactorily completed a training program for teaching the subjects they are expected to teach, or they shall have the academic credentials and instructional experience necessary for teaching the subjects. Instructors shall demonstrate competent instructional skills and knowledge of the applicable subject matter.
Employees and supervisors that have received and successfully completed the training and field experience specified in paragraphs (e)(1) through (e)(4) of this section shall be certified by their instructor or the head instructor and trained supervisor as having successfully completed the necessary training. A written certificate shall be given to each person so certified. Any person who has not been so certified or who does not meet the requirements of paragraph (e)(9) of this section shall be prohibited from engaging in hazardous waste operations.
Employees who are engaged in responding to hazardous emergency situations at hazardous waste clean-up sites that may expose them to hazardous substances shall be trained in how to respond to such expected emergencies.
Employees specified in paragraph (e)(1) of this section, and managers and supervisors specified in paragraph (e)(4) of this section, shall receive eight hours of refresher training annually on the items specified in paragraph (e)(2) and/or (e)(4) of this section, any critique of incidents that have occurred in the past year that can serve as training examples of related work, and other relevant topics.
Employers who can show by documentation or certification that an employee's work experience and/or training has resulted in training equivalent to that training required in paragraphs (e)(1) through (e)(4) of this section shall not be required to provide the initial training requirements of those paragraphs to such employees and shall provide a copy of the certification or documentation to the employee upon request. However, certified employees or employees with equivalent training new to a site shall receive appropriate, site specific training before site entry and have appropriate supervised field experience at the new site. Equivalent training includes any academic training or the training that existing employees might have already received from actual hazardous waste site work experience.
Employers engaged in operations specified in paragraphs (a)(1)(i) through (a)(1)(iv) of this section and not covered by (a)(2)(iii) exceptions and employers of employees specified in paragraph (q)(9) shall institute a medical surveillance program in accordance with this paragraph.
The medical surveillance program shall be instituted by the employer for the following employees:
Medical examinations and consultations shall be made available by the employer to each employee covered under paragraph (f)(2) of this section on the following schedules:
All medical examinations and procedures shall be performed by or under the supervision of a licensed physician, preferably one knowledgeable in occupational medicine, and shall be provided without cost to the employee, without loss of pay, and at a reasonable time and place.
The employer shall provide one copy of this standard and its appendices to the attending physician, and in addition the following for each employee:
A written personal protective equipment program, which is part of the employer's safety and health program required in paragraph (b) of this section or required in paragraph (p)(1) of this section and which is also a part of the site-specific safety and health plan shall be established. The PPE program shall address the elements listed below. When elements, such as donning and doffing procedures, are provided by the manufacturer of a piece of equipment and are attached to the plan, they need not be rewritten into the plan as long as they adequately address the procedure or element.
selection based upon site hazards,
use and limitations of the equipment,
maintenance and storage,
decontamination and disposal,
training and proper fitting,
donning and doffing procedures,
inspection procedures prior to, during, and after use,
Upon initial entry, representative air monitoring shall be conducted to identify any IDLH condition, exposure over permissible exposure limits or published exposure levels, exposure over a radioactive material's dose limits or other dangerous condition such as the presence of flammable atmospheres or oxygen-deficient environments.
Periodic monitoring shall be conducted when the possibility of an IDLH condition or flammable atmosphere has developed or when there is indication that exposures may have risen over permissible exposure limits or published exposure levels since prior monitoring. Situations where it shall be considered whether the possibility that exposures have risen are as follows:
After the actual clean-up phase of any hazardous waste operation commences; for example, when soil, surface water or containers are moved or disturbed; the employer shall monitor those employees likely to have the highest exposures to hazardous substances and health hazards likely to be present above permissible exposure limits or published exposure levels by using personal sampling frequently enough to characterize employee exposures. If the employees likely to have the highest exposure are over permissible exposure limits or published exposure limits, then monitoring shall continue to determine all employees likely to be above those limits. The employer may utilize a representative sampling approach by documenting that the employees and chemicals chosen for monitoring are based on the criteria stated above.
Employers shall develop and implement a program, which is part of the employer's safety and health program required in paragraph (b) of this section, to inform employees, contractors, and subcontractors (or their representative) actually engaged in hazardous waste operations of the nature, level and degree of exposure likely as a result of participation in such hazardous waste operations. Employees, contractors and subcontractors working outside of the operations part of a site are not covered by this standard.
Department of Transportation specified salvage drums or containers and suitable quantities of proper absorbent shall be kept available and used in areas where spills, leaks, or ruptures may occur.
The following procedures shall be followed in areas where drums or containers are being opened:
Material handiing equipment used to transfer drums and containers shall be selected, positioned and operated to minimize sources of ignition related to the equipment from igniting vapors released from ruptured drums or containers.
Drums and containers containing radioactive wastes shall not be handled until such time as their hazard to employees is properly assessed.
As a minimum, the following special precautions shall be taken when drums and containers containing or suspected of containing shock-sensitive wastes are handled:
Caution: Shipping of shock sensitive wastes may be prohibited under U.S. Department of Transportation regulations. Employers and their shippers should refer to 49 CFR 173.21 and 173.50.
In addition to the requirements of paragraph (j)(5) of this section, the following precautions shall be taken, as a minimum, in handling laboratory waste packs (lab packs):
Sampling of containers and drums shall be done in accordance with a sampling procedure which is part of the site safety and health plan developed for and available to employees and others at the specific worksite.
Procedures for all phases of decontamination shall be developed and implemented in accordance with this paragraph.
Decontamination shall be performed in geographical areas that will minimize the exposure of uncontaminated employees or equipment to contaminated employees or equipment.
All equipment and solvents used for decontamination shall be decontaminated or disposed of properly.
Unauthorized employees shall not remove protective clothing or equipment from change rooms.
Commercial laundries or cleaning establishments that decontaminate protective clothing or equipment shall be informed of the potentially harmful effects of exposures to hazardous substances.
Where the decontamination procedure indicates a need for regular showers and change rooms outside of a contaminated area, they shall be provided and meet the requirements of 29 CFR 1910.141. If temperature conditions prevent the effective use of water, then other effective means for cleansing shall be provided and used.
The employer shall develop an emergency response plan for emergencies which shall address, as a minimum, the following:
and emergency equipment.
Areas accessible to employees shall be lighted to not less than the minimum illumination intensities listed in the following Table D-65.1 while any work is in progress:
| Foot-candles | Area or operations |
|---|---|
| 5 | General site areas. |
| 3 | Excavation and waste areas, accessways, active storage areas, loading platforms, refueling, and field maintenance areas. |
| 5 | Indoors: Warehouses, corridors, hallways, and exitways. |
| 5 | Tunnels, shafts, and general underground work areas. (Exception: Minimum of 10 foot-candles is required at tunnel and shaft heading during drilling mucking, and scaling. Mine Safety and Health Administration approved cap lights shall be acceptable for use in the tunnel heading.) |
| 10 | General shops (e.g., mechanical and electrical equipment rooms, active storerooms, barracks or living quarters, locker or dressing rooms, dining areas, and indoor toilets and workrooms.) |
| 30 | First aid stations, infirmaries, and offices. |
| Number of employees | Minimum number of facilities |
|---|---|
| 20 or fewer | One. |
| More than 20, fewer than 200 | One toilet seat and one urinal per 40 employees. |
| More than 200 | One toilet seat and one urinal per 50 employees. |
All food service facilities and operations for employees shall meet the applicable laws, ordinances, and regulations of the jurisdictions in which they are located.
When temporary sleeping quarters are provided, they shall be heated, ventilated, and lighted.
The employer shall provide adequate washing facilities for employees engaged in operations where hazardous substances may be harmful to employees. Such facilities shall be in near proximity to the worksite; in areas where exposures are below permissible exposure limits and published exposure levels and which are under the controls of the employer; and shall be so equipped as to enable employees to remove hazardous substances from themselves.
When hazardous waste clean-up or removal operations commence on a site and the duration of the work will require six months or greater time to complete, the employer shall provide showers and change rooms for all employees exposed to hazardous substances and health hazards involved in hazardous waste clean-up or removal operations.
The employer shall develop and implement a written safety and health program for employees involved in hazardous waste operations that shall be available for inspection by employees, their representatives and OSHA personnel. The program shall be designed to identify, evaluate and control safety and health hazards in their facilities for the purpose of employee protection, to provide for emergency response meeting the requirements of paragraph (p)(8) of this section and to address as appropriate site analysis, engineering controls, maximum exposure limits, hazardous waste handling procedures and uses of new technologies.
The employer shall implement a hazard communication program meeting the requirements of 29 CFR 1926.59 as part of the employer's safety and program.
The employer shall develop and implement a medical surveillance program meeting the requirements of paragraph (f) of this section.
The employer shall develop and implement a decontamination procedure meeting the requirements of paragraph (k) of this section.
The employer shall develop and implement procedures meeting the requirements of paragraph (o) of this section for introducing new and innovative equipment into the workplace.
Where employees will be handling drums or containers, the employer shall develop and implement procedures meeting the requirements of paragraphs (j)(1) (ii) through (viii) and (xi) of this section, as well as (j)(3) and (j)(8) of this section prior to starting such work.
The employer shall develop and implement a training program, which is part of the employer's safety and health program, for employees exposed to health hazards or hazardous substances at TSD operations to enable the employees to perform their assigned duties and functions in a safe and healthful manner so as not endanger themselves or other employees. The initial training shall be for 24 hours and refresher training shall be for eight hours annually. Employees who have received the initial training required by this paragraph shall be given a written certificate attesting that they have successfully completed the necessary training.
Employers who can show by an employee's previous work experience and/or training that the employee has had training equivalent to the initial training required by this paragraph, shall be considered as meeting the initial training requirements of this paragraph as to that employee. Equivalent training includes the training that existing employees might have already received from actual site work experience. Current employees shall receive eight hours of refresher training annually.
Trainers who teach initial training shall have satisfactorily completed a training course for teaching the subjects they are expected to teach or they shall have the academic credentials and instruction experience necessary to demonstrate a good command of the subject matter of the courses and competent instructional skills.
An emergency response plan shall be developed and implemented by all employers. Such plans need not duplicate any of the subjects fully addressed in the employer's contingency planning required by permits, such as those issued by the U.S. Environmental Protection Agency, provided that the contingency plan is made part of the emergency response plan. The emergency response plan shall be a written portion of the employers safety and health program required in paragraph (p)(1) of this section. Employers who will evacuate their employees from the worksite location when an emergency occurs and who do not permit any of their employees to assist in handling the emergency are exempt from the requirements of paragraph (p)(8) if they provide an emergency action plan complying with § 1926.35 of this part.
The employer shall develop an emergency response plan for emergencies which shall address, as a minimum, the following areas to the extent that they are not addressed in any specific program required in this paragraph:
and emergency equipment.
Exception #1:
Exception #2:
This paragraph covers employers whose employees are engaged in emergency response no matter where it occurs except that it does not cover employees engaged in operations specified in paragraphs (a)(1)(i) through (a)(1)(iv) of this section. Those emergency response organizations who have developed and implemented programs equivalent to this paragraph for handling releases of hazardous substances pursuant to section 303 of the Superfund Amendments and Reauthorization Act of 1986 (Emergency Planning and Community Right-to-Know Act of 1986, 42 U.S.C. 11003) shall be deemed to have met the requirements of this paragraph.
An emergency response plan shall be developed and implemented to handle anticipated emergencies prior to the commencement of emergency response operations. The plan shall be in writing and available for inspection and copying by employees, their representatives and OSHA personnel. Employers who will evacuate their employees from the danger area when an emergency occurs, and who do not permit any of their employees to assist in handling the emergency, are exempt from the requirements of this paragraph if they provide an emergency action plan in accordance with § 1926.35 of this part.
The employer shall develop an emergency response plan for emergencies which shall address, as a minimum, the following to the extent that they are not addressed elsewhere:
and emergency equipment.
Personnel, not necessarily an employer's own employees, who are skilled in the operation of certain equipment, such as mechanized earth moving or digging equipment or crane and hoisting equipment, and who are needed temporarily to perform immediate emergency support work that cannot reasonably be performed in a timely fashion by an employer's own employees, and who will be or may be exposed to the hazards at an emergency response scene, are not required to meet the training required in this paragraph for the employer's regular employees. However, these personnel shall be given an initial briefing at the site prior to their participation in any emergency response. The initial briefing shall include instruction in the wearing of appropriate personal protective equipment, what chemical hazards are involved, and what duties are to be performed. All other appropriate safety and health precautions provided to the employer's own employees shall be used to assure the safety and health of these personnel.
Employees who, in the course of their regular job duties, work with and are trained in the hazards of specific hazardous substances, and who will be called upon to provide technical advice or assistance at a hazardous substance release incident to the individual in charge, shall receive training or demonstrate competency in the area of their specialization annually.
Training shall be based on the duties and function to be performed by each responder of an emergency response organization. The skill and knowledge levels required for all new responders, those hired after the effective date of this standard, shall be conveyed to them through training before they are permitted to take part in actual emergency operations on an incident. Employees who participate, or are expected to participate, in emergency response, shall be given training in accordance with the following paragraphs:
First responders at the awareness level are individuals who are likely to witness or discover a hazardous substance release and who have been trained to initiate an emergency response sequence by notifying the proper authorities of the release. They would take no further action beyond notifying the authorities of the release. First responders at the awareness level shall have sufficient training or have had sufficient experience to objectively demonstrate competency in the following areas:
First responders at the operations level are individuals who respond to releases or potential releases of hazardous substances as part of the initial response to the site for the purpose of protecting nearby persons, property, or the environment from the effects of the release. They are trained to respond in a defensive fashion without actually trying to stop the release. Their function is to contain the release from a safe distance, keep it from spreading, and prevent exposures. First responders at the operational level shall have received at least eight hours of training or have had sufficient experience to objectively demonstrate competency in the following areas in addition to those listed for the awareness level and the employer shall so certify:
Hazardous materials technicians are individuals who respond to releases or potential releases for the purpose of stopping the release. They assume a more aggressive role than a first responder at the operations level in that they will approach the point of release in order to plug, patch or otherwise stop the release of a hazardous substance. Hazardous materials technicians shall have received at least 24 hours of training equal to the first responder operations level and in addition have competency in the following areas and the employer shall so certify:
Hazardous materials specialists are individuals who respond with and provide support to hazardous materials technicians. Their duties parallel those of the hazardous materials technician, however, those duties require a more directed or specific knowledge of the various substances they may be called upon to contain. The hazardous materials specialist would also act as the site liaison with Federal, state, local and other government authorities in regards to site activities. Hazardous materials specialists shall have received at least 24 hours of training equal to the technician level and in addition have competency in the following areas and the employer shall so certify:
Incident commanders, who will assume control of the incident scene beyond the first responder awareness level, shall receive at least 24 hours of training equal to the first responder operations level and in addition have competency in the following areas and the employer shall so certify:
Trainers who teach any of the above training subjects shall have satisfactorily completed a training course for teaching the subjects they are expected to teach, such as the courses offered by the U.S. National Fire Academy, or they shall have the training and/or academic credentials and instructional experience necessary to demonstrate competent instructional skills and a good command of the subject matter of the courses they are to teach.
Chemical protective clothing and equipment to be used by organized and designated HAZMAT team members, or to be used by hazardous materials specialists, shall meet the requirements of paragraphs (g) (3) through (5) of this section.
Upon completion of the emergency response, if it is determined that it is necessary to remove hazardous substances, health hazards, and materials contaminated with them (such as contaminated soil or other elements of the natural environment) from the site of the incident, the employer conducting the clean-up shall comply with one of the following:
Appendix A to § 1926.65—Personal Protective Equipment Test Methods
This appendix sets forth the non-mandatory examples of tests which may be used to evaluate compliance with § 1926.65(g)(4) (ii) and (iii). Other tests and other challenge agents may be used to evaluate compliance.
A. Totally-encapsulating chemical protective suit pressure test
1.0—Scope
1.1 This practice measures the ability of a gas tight totally-encapsulating chemical protective suit material, seams, and closures to maintain a fixed positive pressure. The results of this practice allow the gas tight integrity of a totally-encapsulating chemical protective suit to be evaluated.
1.2 Resistance of the suit materials to permeation, penetration, and degradation by specific hazardous substances is not determined by this test method.
2.0—Definition of terms
2.1 Totally-encapsulated chemical protective suit (TECP suit) means a full body garment which is constructed of protective clothing materials; covers the wearer's torso, head, arms, legs and respirator; may cover the wearer's hands and feet with tightly attached gloves and boots; completely encloses the wearer and respirator by itself or in combination with the wearer's gloves and boots.
2.2 Protective clothing material means any material or combination of materials used in an item of clothing for the purpose of isolating parts of the body from direct contact with a potentially hazardous liquid or gaseous chemicals.
2.3 Gas tight means, for the purpose of this test method, the limited flow of a gas under pressure from the inside of a TECP suit to atmosphere at a prescribed pressure and time interval.
3.0—Summary of test method
3.1 The TECP suit is visually inspected and modified for the test. The test apparatus is attached to the suit to permit inflation to the pre-test suit expansion pressure for removal of suit wrinkles and creases. The pressure is lowered to the test pressure and monitored for three minutes. If the pressure drop is excessive, the TECP suit fails the test and is removed from service. The test is repeated after leak location and repair.
4.0—Required Supplies
4.1 Source of compressed air.
4.2 Test apparatus for suit testing, including a pressure measurement device with a sensitivity of at least 1/4 inch water gauge.
4.3 Vent valve closure plugs or sealing tape.
4.4 Soapy water solution and soft brush.
4.5 Stop watch or appropriate timing device.
5.0—Safety Precautions
5.1 Care shall be taken to provide the correct pressure safety devices required for the source of compressed air used.
6.0—Test Procedure
6.1 Prior to each test, the tester shall perform a visual inspection of the suit. Check the suit for seam integrity by visually examining the seams and gently pulling on the seams. Ensure that all air supply lines, fittings, visor, zippers, and valves are secure and show no signs of deterioration.
6.1.1 Seal off the vent valves along with any other normal inlet or exhaust points (such as umbilical air line fittings or face piece opening) with tape or other appropriate means (caps, plugs, fixture, etc.). Care should be exercised in the sealing process not to damage any of the suit components.
6.1.2 Close all closure assemblies.
6.1.3 Prepare the suit for inflation by providing an improvised connection point on the suit for connecting an airline. Attach the pressure test apparatus to the suit to permit suit inflation from a compressed air source equipped with a pressure indicating regulator. The leak tightness of the pressure test apparatus should be tested before and after each test by closing off the end of the tubing attached to the suit and assuring a pressure of three inches water gauge for three minutes can be maintained. If a component is removed for the test, that component shall be replaced and a second test conducted with another component removed to permit a complete test of the ensemble.
6.1.4 The pre-test expansion pressure (A) and the suit test pressure (B) shall be supplied by the suit manufacturer, but in no case shall they be less than: (A) = three inches water gauge; and (B) = two inches water gauge. The ending suit pressure (C) shall be no less than 80 percent of the test pressure (B); i.e., the pressure drop shall not exceed 20 percent of the test pressure (B).
6.1.5 Inflate the suit until the pressure inside is equal to pressure (A), the pre-test expansion suit pressure. Allow at least one minute to fill out the wrinkles in the suit. Release sufficient air to reduce the suit pressure to pressure (B), the suit test pressure. Begin timing. At the end of three minutes, record the suit pressure as pressure (C), the ending suit pressure. The difference between the suit test pressure and the ending suit test pressure (B-C) shall be defined as the suit pressure drop.
6.1.6 If the suit pressure drop is more than 20 percent of the suit test pressure (B) during the three-minute test period, the suit fails the test and shall be removed from service.
7.0—Retest Procedure
7.1 If the suit fails the test check for leaks by inflating the suit to pressure (A) and brushing or wiping the entire suit (including seams, closures, lens gaskets, glove-to-sleeve joints, etc.) with a mild soap and water solution. Observe the suit for the formation of soap bubbles, which is an indication of a leak. Repair all identified leaks.
7.2 Retest the TECP suit as outlined in Test procedure 6.0.
8.0—Report
8.1 Each TECP suit tested by this practice shall have the following information recorded:
8.1.1 Unique identification number, identifying brand name, date of purchase, material of construction, and unique fit features, e.g., special breathing apparatus.
8.1.2 The actual values for test pressures (A), (B), and (C) shall be recorded along with the specific observation times. If the ending pressure (C) is less than 80 percent of the test pressure (B), the suit shall be identified as failing the test. When possible, the specific leak location shall be identified in the test records. Retest pressure data shall be recorded as an additional test.
8.1.3 The source of the test apparatus used shall be identified and the sensitivity of the pressure gauge shall be recorded.
8.1.4 Records shall be kept for each pressure test even if repairs are being made at the test location.
CAUTION
Visually inspect all parts of the suit to be sure they are positioned correctly and secured tightly before putting the suit back into service. Special care should be taken to examine each exhaust valve to make sure it is not blocked.
Care should also be exercised to assure that the inside and outside of the suit is completely dry before it is put into storage.
B. Totally-encapsulating chemical protective suit qualitative leak test
1.0—Scope
1.1 This practice semi-qualitatively tests gas tight totally-encapsulating chemical protective suit integrity by detecting inward leakage of ammonia vapor. Since no modifications are made to the suit to carry out this test, the results from this practice provide a realistic test for the integrity of the entire suit.
1.2 Resistance of the suit materials to permeation, penetration, and degradation is not determined by this test method. ASTM test methods are available to test suit materials for these characteristics and the tests are usually conducted by the manufacturers of the suits.
2.0—Definition of terms
2.1 Totally-encapsulated chemical protective suit (TECP suit) means a full body garment which is constructed of protective clothing materials; covers the wearer's torso, head, arms, legs and respirator; may cover the wearer's hands and feet with tightly attached gloves and boots; completely encloses the wearer and respirator by itself or in combination with the wearer's gloves, and boots.
2.2 Protective clothing material means any material or combination of materials used in an item of clothing for the purpose of isolating parts of the body from direct contact with a potentially hazardous liquid or gaseous chemicals.
2.3 Gas tight means, for the purpose of this test method, the limited flow of a gas under pressure from the inside of a TECP suit to atmosphere at a prescribed pressure and time interval.
2.4 Intrusion Coefficient means a number expressing the level of protection provided by a gas tight totally-encapsulating chemical protective suit. The intrusion coefficient is calculated by dividing the test room challenge agent concentration by the concentration of challenge agent found inside the suit. The accuracy of the intrusion coefficient is dependent on the challenge agent monitoring methods. The larger the intrusion coefficient the greater the protection provided by the TECP suit.
3.0—Summary of recommended practice
3.1 The volume of concentrated aqueous ammonia solution (ammonia hydroxide NH 4 OH) required to generate the test atmosphere is determined using the directions outlined in 6.1. The suit is donned by a person wearing the appropriate respiratory equipment (either a positive pressure self-contained breathing apparatus or a positive pressure supplied air respirator) and worn inside the enclosed test room. The concentrated aqueous ammonia solution is taken by the suited individual into the test room and poured into an open plastic pan. A two-minute evaporation period is observed before the test room concentration is measured, using a high range ammonia length of stain detector tube. When the ammonia vapor reaches a concentration of between 1000 and 1200 ppm, the suited individual starts a standardized exercise protocol to stress and flex the suit. After this protocol is completed, the test room concentration is measured again. The suited individual exits the test room and his stand-by person measures the ammonia concentration inside the suit using a low range ammonia length of stain detector tube or other more sensitive ammonia detector. A stand-by person is required to observe the test individual during the test procedure; aid the person in donning and doffing the TECP suit; and monitor the suit interior. The intrusion coefficient of the suit can be calculated by dividing the average test area concentration by the interior suit concentration. A colorimetric ammonia indicator strip of bromophenol blue or equivalent is placed on the inside of the suit face piece lens so that the suited individual is able to detect a color change and know if the suit has a significant leak. If a color change is observed the individual shall leave the test room immediately.
4.0—Required supplies
4.1 A supply of concentrated aqueous ammonium hydroxide (58% by weight).
4.2 A supply of bromophenol/blue indicating paper or equivalent, sensitive to 5-10 ppm ammonia or greater over a two-minute period of exposure. [pH 3.0 (yellow) to pH 4.6 (blue)]
4.3 A supply of high range (0.5-10 volume percent) and low range (5-700 ppm) detector tubes for ammonia and the corresponding sampling pump. More sensitive ammonia detectors can be substituted for the low range detector tubes to improve the sensitivity of this practice.
4.4 A shallow plastic pan (PVC) at least 12″:14″:1″ and a half pint plastic container (PVC) with tightly closing lid.
4.5 A graduated cylinder or other volumetric measuring device of at least 50 milliliters in volume with an accuracy of at least ±1 milliliters.
5.0—Safety precautions
5.1 Concentrated aqueous ammonium hydroxide, NH 4 OH, is a corrosive volatile liquid requiring eye, skin, and respiratory protection. The person conducting the test shall review the Safety Data Sheet (SDS) for aqueous ammonia.
5.2 Since the established permissible exposure limit for ammonia is 35 ppm as a 15 minute STEL, only persons wearing a positive pressure self-contained breathing apparatus or a positive pressure supplied air respirator shall be in the chamber. Normally only the person wearing the totally-encapsulating suit will be inside the chamber. A stand-by person shall have a positive pressure self-contained breathing apparatus, or a positive pressure supplied air respirator available to enter the test area should the suited individual need assistance.
5.3 A method to monitor the suited individual must be used during this test. Visual contact is the simplest but other methods using communication devices are acceptable.
5.4 The test room shall be large enough to allow the exercise protocol to be carried out and then to be ventilated to allow for easy exhaust of the ammonia test atmosphere after the test(s) are completed.
5.5 Individuals shall be medically screened for the use of respiratory protection and checked for allergies to ammonia before participating in this test procedure.
6.0—Test procedure
6.1.1 Measure the test area to the nearest foot and calculate its volume in cubic feet. Multiply the test area volume by 0.2 milliliters of concentrated aqueous ammonia solution per cubic foot of test area volume to determine the approximate volume of concentrated aqueous ammonia required to generate 1000 ppm in the test area.
6.1.2 Measure this volume from the supply of concentrated aqueous ammonia and place it into a closed plastic container.
6.1.3 Place the container, several high range ammonia detector tubes, and the pump in the clean test pan and locate it near the test area entry door so that the suited individual has easy access to these supplies.
6.2.1 In a non-contaminated atmosphere, open a pre-sealed ammonia indicator strip and fasten one end of the strip to the inside of the suit face shield lens where it can be seen by the wearer. Moisten the indicator strip with distilled water. Care shall be taken not to contaminate the detector part of the indicator paper by touching it. A small piece of masking tape or equivalent should be used to attach the indicator strip to the interior of the suit face shield.
6.2.2 If problems are encountered with this method of attachment, the indicator strip can be attached to the outside of the respirator face piece lens being used during the test.
6.3 Don the respiratory protective device normally used with the suit, and then don the TECP suit to be tested. Check to be sure all openings which are intended to be sealed (zippers, gloves, etc.) are completely sealed. DO NOT, however, plug off any venting valves.
6.4 Step into the enclosed test room such as a closet, bathroom, or test booth, equipped with an exhaust fan. No air should be exhausted from the chamber during the test because this will dilute the ammonia challenge concentrations.
6.5 Open the container with the pre-measured volume of concentrated aqueous ammonia within the enclosed test room, and pour the liquid into the empty plastic test pan. Wait two minutes to allow for adequate volatilization of the concentrated aqueous ammonia. A small mixing fan can be used near the evaporation pan to increase the evaporation rate of the ammonia solution.
6.6 After two minutes a determination of the ammonia concentration within the chamber should be made using the high range colorimetric detector tube. A concentration of 1000 ppm ammonia or greater shall be generated before the exercises are started.
6.7 To test the integrity of the suit the following four minute exercise protocol should be followed:
6.7.1 Raising the arms above the head with at least 15 raising motions completed in one minute.
6.7.2 Walking in place for one minute with at least 15 raising motions of each leg in a one-minute period.
6.7.3 Touching the toes with a least 10 complete motions of the arms from above the head to touching of the toes in a one-minute period.
6.7.4 Knee bends with at least 10 complete standing and squatting motions in a one-minute period.
6.8 If at any time during the test the colorimetric indicating paper should change colors, the test should be stopped and section 6.10 and 6.12 initiated (See ¶ 4.2).
6.9 After completion of the test exercise, the test area concentration should be measured again using the high range colorimetric detector tube.
6.10 Exit the test area.
6.11 The opening created by the suit zipper or other appropriate suit penetration should be used to determine the ammonia concentration in the suit with the low range length of stain detector tube or other ammonia monitor. The internal TECP suit air should be sampled far enough from the enclosed test area to prevent a false ammonia reading.
6.12 After completion of the measurement of the suit interior ammonia concentration the test is concluded and the suit is doffed and the respirator removed.
6.13 The ventilating fan for the test room should be turned on and allowed to run for enough time to remove the ammonia gas. The fan shall be vented to the outside of the building.
6.14 Any detectable ammonia in the suit interior (five ppm ammonia (NH 3 ) or more for the length of stain detector tube) indicates that the suit has failed the test. When other ammonia detectors are used a lower level of detection is possible, and it should be specified as the pass/fail criteria.
6.15 By following this test method, an intrusion coefficient of approximately 200 or more can be measured with the suit in a completely operational condition. If the intrusion coefficient is 200 or more, then the suit is suitable for emergency response and field use.
7.0—Retest procedures
7.1 If the suit fails this test, check for leaks by following the pressure test in test A above.
7.2 Retest the TECP suit as outlined in the test procedure 6.0.
8.0—Report
8.1 Each gas tight totally-encapsulating chemical protective suit tested by this practice shall have the following information recorded.
8.1.1 Unique identification number, identifying brand name, date of purchase, material of construction, and unique suit features; e.g., special breathing apparatus.
8.1.2 General description of test room used for test.
8.1.3 Brand name and purchase date of ammonia detector strips and color change data.
8.1.4 Brand name, sampling range, and expiration date of the length of stain ammonia detector tubes. The brand name and model of the sampling pump should also be recorded. If another type of ammonia detector is used, it should be identified along with its minimum detection limit for ammonia.
8.1.5 Actual test results shall list the two test area concentrations, their average, the interior suit concentration, and the calculated intrusion coefficient. Retest data shall be recorded as an additional test.
8.2 The evaluation of the data shall be specified as “suit passed” or “suit failed,” and the date of the test. Any detectable ammonia (five ppm or greater for the length of stain detector tube) in the suit interior indicates the suit has failed this test. When other ammonia detectors are used, a lower level of detection is possible and it should be specified as the pass fail criteria.
CAUTION
Visually inspect all parts of the suit to be sure they are positioned correctly and secured tightly before putting the suit back into service. Special care should be taken to examine each exhaust valve to make sure it is not blocked.
Care should also be exercised to assure that the inside and outside of the suit is completely dry before it is put into storage.
Appendix B to § 1926.65—General Description and Discussion of the Levels of Protection and Protective Gear
This appendix sets forth information about personal protective equipment (PPE) protection levels which may be used to assist employers in complying with the PPE requirements of this section.
As required by the standard, PPE must be selected which will protect employees from the specific hazards which they are likely to encounter during their work on-site.
Selection of the appropriate PPE is a complex process which should take into consideration a variety of factors. Key factors involved in this process are identification of the hazards, or suspected hazards; their routes of potential hazard to employees (inhalation, skin absorption, ingestion, and eye or skin contact); and the performance of the PPE materials (and seams) in providing a barrier to these hazards. The amount of protection provided by PPE is material-hazard specific. That is, protective equipment materials will protect well against some hazardous substances and poorly, or not at all, against others. In many instances, protective equipment materials cannot be found which will provide continuous protection from the particular hazardous substance. In these cases the breakthrough time of the protective material should exceed the work durations.
Other factors in this selection process to be considered are matching the PPE to the employee's work requirements and task-specific conditions. The durability of PPE materials, such as tear strength and seam strength, should be considered in relation to the employee's tasks. The effects of PPE in relation to heat stress and task duration are a factor in selecting and using PPE. In some cases layers of PPE may be necessary to provide sufficient protection, or to protect expensive PPE inner garments, suits or equipment.
The more that is known about the hazards at the site, the easier the job of PPE selection becomes. As more information about the hazards and conditions at the site becomes available, the site supervisor can make decisions to up-grade or down-grade the level of PPE protection to match the tasks at hand.
The following are guidelines which an employer can use to begin the selection of the appropriate PPE. As noted above, the site information may suggest the use of combinations of PPE selected from the different protection levels (i.e., A, B, C, or D) as being more suitable to the hazards of the work. It should be cautioned that the listing below does not fully address the performance of the specific PPE material in relation to the specific hazards at the job site, and that PPE selection, evaluation and re-selection is an ongoing process until sufficient information about the hazards and PPE performance is obtained.
Part A. Personal protective equipment is divided into four categories based on the degree of protection afforded. (See part B of this appendix for further explanation of Levels A, B, C, and D hazards.)
I. Level A— To be selected when the greatest level of skin, respiratory, and eye protection is required.
The following constitute Level A equipment; it may be used as appropriate;
1. Positive pressure, full face-piece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA, approved by the National Institute for Occupational Safety and Health (NIOSH).
2. Totally-encapsulating chemical-protective suit.
3. Coveralls. 1
4. Long underwear. 1
5. Gloves, outer, chemical-resistant.
6. Gloves, inner, chemical-resistant.
7. Boots, chemical-resistant, steel toe and shank.
8. Hard hat (under suit). 1
9. Disposable protective suit, gloves and boots (depending on suit construction, may be worn over totally-encapsulating suit).
II. Level B —The highest level of respiratory protection is necessary but a lesser level of skin protection is needed.
The following constitute Level B equipment; it may be used as appropriate.
1. Positive pressure, full-facepiece self-contained breathing apparatus (SCBA), or positive pressure supplied air respirator with escape SCBA (NIOSH approved).
2. Hooded chemical-resistant clothing (overalls and long-sleeved jacket; coveralls; one or two-piece chemical-splash suit; disposable chemical-resistant overalls).
3. Coveralls. 1
4. Gloves, outer, chemical-resistant.
5. Gloves, inner, chemical-resistant.
6. Boots, outer, chemical-resistant steel toe and shank.
7. Boot-covers, outer, chemical-resistant (disposable). 1
8. Hard hat. 1
9. [Reserved]
10. Face shield. 1
III. Level C —The concentration(s) and type(s) of airborne substance(s) is known and the criteria for using air purifying respirators are met.
The following constitute Level C equipment; it may be used as appropriate.
1. Full-face or half-mask, air purifying respirators (NIOSH approved).
2. Hooded chemical-resistant clothing (overalls; two-piece chemical-splash suit; disposable chemical-resistant overalls).
3. Coveralls. 1
1 Optional, as applicable.
4. Gloves, outer, chemical-resistant.
5. Gloves, inner, chemical-resistant.
6. Boots (outer), chemical-resistant steel toe and shank. 1
7. Boot-covers, outer, chemical-resistant (disposable) 1.
8. Hard hat. 1
9. Escape mask. 1
10. Face shield. 1
IV. Level D —A work uniform affording minimal protection, used for nuisance contamination only.
The following constitute Level D equipment; it may be used as appropriate:
1. Coveralls.
2. Gloves. 1
3. Boots/shoes, chemical-resistant steel toe and shank.
4. Boots, outer, chemical-resistant (disposable). 1
5. Safety glasses or chemical splash goggles *.
6. Hard hat. 1
7. Escape mask. 1
8. Face shield. 1
Part B. The types of hazards for which levels A, B, C, and D protection are appropriate are described below:
I. Level A —Level A protection should be used when:
1. The hazardous substance has been identified and requires the highest level of protection for skin, eyes, and the respiratory system based on either the measured (or potential for) high concentration of atmospheric vapors, gases, or particulates; or the site operations and work functions involve a high potential for splash, immersion, or exposure to unexpected vapors, gases, or particulates of materials that are harmful to skin or capable of being absorbed through the skin;
2. Substances with a high degree of hazard to the skin are known or suspected to be present, and skin contact is possible; or
3. Operations are being conducted in confined, poorly ventilated areas, and the absence of conditions requiring Level A have not yet been determined.
II. Level B —Level B protection should be used when:
1. The type and atmospheric concentration of substances have been identified and require a high level of respiratory protection, but less skin protection;
2. The atmosphere contains less than 19.5 percent oxygen; or
3. The presence of incompletely identified vapors or gases is indicated by a direct-reading organic vapor detection instrument, but vapors and gases are not suspected of containing high levels of chemicals harmful to skin or capable of being absorbed through the skin.
III. Level C —Level C protection should be used when:
1. The atmospheric contaminants, liquid splashes, or other direct contact will not adversely affect or be absorbed through any exposed skin;
2. The types of air contaminants have been identified, concentrations measured, and an air-purifying respirator is available that can remove the contaminants; and
3. All criteria for the use of air-purifying respirators are met.
IV. Level D —Level D protection should be used when:
1. The atmosphere contains no known hazard; and
2. Work functions preclude splashes, immersion, or the potential for unexpected inhalation of or contact with hazardous levels of any chemicals.
Appendix C to § 1926.65—Compliance Guidelines
1. Occupational Safety and Health Program. Each hazardous waste site clean-up effort will require an occupational safety and health program headed by the site coordinator or the employer's representative. The purpose of the program will be the protection of employees at the site and will be an extension of the employer's overall safety and health program. The program will need to be developed before work begins on the site and implemented as work proceeds as stated in paragraph (b). The program is to facilitate coordination and communication of safety and health issues among personnel responsible for the various activities which will take place at the site. It will provide the overall means for planning and implementing the needed safety and health training and job orientation of employees who will be working at the site. The program will provide the means for identifying and controlling worksite hazards and the means for monitoring program effectiveness. The program will need to cover the responsibilities and authority of the site coordinator or the employer's manager on the site for the safety and health of employees at the site, and the relationships with contractors or support services as to what each employer's safety and health responsibilities are for their employees on the site. Each contractor on the site needs to have its own safety and health program so structured that it will smoothly interface with the program of the site coordinator or principal contractor.
Also those employers involved with treating, storing or disposal of hazardous waste as covered in paragraph (p) must have implemented a safety and health program for their employees. This program is to include the hazard communication program required in paragraph (p)(1) and the training required in paragraphs (p)(7) and (p)(8) as parts of the employers comprehensive overall safety and health program. This program is to be in writing.
Each site or workplace safety and health program will need to include the following: (1) Policy statements of the line of authority and accountability for implementing the program, the objectives of the program and the role of the site safety and health supervisor or manager and staff; (2) means or methods for the development of procedures for identifying and controlling workplace hazards at the site; (3) means or methods for the development and communication to employees of the various plans, work rules, standard operating procedures and practices that pertain to individual employees and supervisors; (4) means for the training of supervisors and employees to develop the needed skills and knowledge to perform their work in a safe and healthful manner; (5) means to anticipate and prepare for emergency situations; and (6) means for obtaining information feedback to aid in evaluating the program and for improving the effectiveness of the program. The management and employees should be trying continually to improve the effectiveness of the program thereby enhancing the protection being afforded those working on the site.
Accidents on the site or workplace should be investigated to provide information on how such occurrences can be avoided in the future. When injuries or illnesses occur on the site or workplace, they will need to be investigated to determine what needs to be done to prevent this incident from occurring again. Such information will need to be used as feedback on the effectiveness of the program and the information turned into positive steps to prevent any reoccurrence. Receipt of employee suggestions or complaints relating to safety and health issues involved with site or workplace activities is also a feedback mechanism that can be used effectively to improve the program and may serve in part as an evaluative tool(s).
For the development and implementation of the program to be the most effective, professional safety and health personnel should be used. Certified Safety Professionals, Board Certified Industrial Hygienists or Registered Professional Safety Engineers are good examples of professional stature for safety and health managers who will administer the employer's program.
2. Training. The training programs for employees subject to the requirements of paragraph (e) of this standard should address: the safety and health hazards employees should expect to find on hazardous waste clean-up sites; what control measures or techniques are effective for those hazards; what monitoring procedures are effective in characterizing exposure levels; what makes an effective employer's safety and health program; what a site safety and health plan should include; hands on training with personal protective equipment and clothing they may be expected to use; the contents of the OSHA standard relevant to the employee's duties and function; and, employee's responsibilities under OSHA and other regulations. Supervisors will need training in their responsibilities under the safety and health program and its subject areas such as the spill containment program, the personal protective equipment program, the medical surveillance program, the emergency response plan and other areas.
The training programs for employees subject to the requirements of paragraph (p) of this standard should address: the employers safety and health program elements impacting employees; the hazard communication program; the medical surveillance program; the hazards and the controls for such hazards that employees need to know for their job duties and functions. All require annual refresher training.
The training programs for employees covered by the requirements of paragraph (q) of this standard should address those competencies required for the various levels of response such as: the hazards associated with hazardous substances; hazard identification and awareness; notification of appropriate persons; the need for and use of personal protective equipment including respirators; the decontamination procedures to be used; preplanning activities for hazardous substance incidents including the emergency reponse plan; company standard operating procedures for hazardous substance emergency responses; the use of the incident command system and other subjects. Hands-on training should be stressed whenever possible. Critiques done after an incident which include an evaluation of what worked and what did not and how could the incident be better handled the next time may be counted as training time.
For hazardous materials specialists (usually members of hazardous materials teams), the training should address the care, use and/or testing of chemical protective clothing including totally encapsulating suits, the medical surveillance program, the standard operating procedures for the hazardous materials team including the use of plugging and patching equipment and other subject areas.
Officers and leaders who may be expected to be in charge at an incident should be fully knowledgeable of their company's incident command system. They should know where and how to obtain additional assistance and be familiar with the local district's emergency response plan and the state emergency response plan.
Specialist employees such as technical experts, medical experts or environmental experts that work with hazardous materials in their regular jobs, who may be sent to the incident scene by the shipper, manufacturer or governmental agency to advise and assist the person in charge of the incident should have training on an annual basis. Their training should include the care and use of personal protective equipment including respirators; knowledge of the incident command system and how they are to relate to it; and those areas needed to keep them current in their respective field as it relates to safety and health involving specific hazardous substances.
Those skilled support personnel, such as employees who work for public works departments or equipment operators who operate bulldozers, sand trucks, backhoes, etc., who may be called to the incident scene to provide emergency support assistance, should have at least a safety and health briefing before entering the area of potential or actual exposure. These skilled support personnel, who have not been a part of the emergency response plan and do not meet the training requirements, should be made aware of the hazards they face and should be provided all necessary protective clothing and equipment required for their tasks.
There are two National Fire Protection Association standards, NFPA 472—“Standard for Professional Competence of Responders to Hazardous Material Incidents” and NFPA 471—“Recommended Practice for Responding to Hazardous Material Incidents”, which are excellent resource documents to aid fire departments and other emergency response organizations in developing their training program materials. NFPA 472 provides guidance on the skills and knowledge needed for first responder awareness level, first responder operations level, hazmat technicians, and hazmat specialist. It also offers guidance for the officer corp who will be in charge of hazardous substance incidents.
3. Decontamination. Decontamination procedures should be tailored to the specific hazards of the site, and may vary in complexity and number of steps, depending on the level of hazard and the employee's exposure to the hazard. Decontamination procedures and PPE decontamination methods will vary depending upon the specific substance, since one procedure or method may not work for all substances. Evaluation of decontamination methods and procedures should be performed, as necessary, to assure that employees are not exposed to hazards by re-using PPE. References in appendix D may be used for guidance in establishing an effective decontamination program. In addition, the U.S. Coast Guard's Manual, “Policy Guidance for Response to Hazardous Chemical Releases,” U.S. Department of Transportation, Washington, DC (COMDTINST M16465.30) is a good reference for establishing an effective decontamination program.
4. Emergency response plans. States, along with designated districts within the states, will be developing or have developed local emergency response plans. These state and district plans should be utilized in the emergency response plans called for in the standard. Each employer should assure that its emergency response plan is compatible with the local plan. The major reference being used to aid in developing the state and local district plans is the Hazardous Materials Emergency Planning Guide, NRT-1. The current Emergency Response Guidebook from the U.S. Department of Transportation, CMA's CHEMTREC and the Fire Service Emergency Management Handbook may also be used as resources.
Employers involved with treatment, storage, and disposal facilities for hazardous waste, which have the required contingency plan called for by their permit, would not need to duplicate the same planning elements. Those items of the emergency response plan that are properly addressed in the contingency plan may be substituted into the emergency response plan required in 1926.65 or otherwise kept together for employer and employee use.
5. Personal protective equipment programs. The purpose of personal protective clothing and equipment (PPE) is to shield or isolate individuals from the chemical, physical, and biologic hazards that may be encountered at a hazardous substance site.
As discussed in appendix B, no single combination of protective equipment and clothing is capable of protecting against all hazards. Thus PPE should be used in conjunction with other protective methods and its effectiveness evaluated periodically.
The use of PPE can itself create significant worker hazards, such as heat stress, physical and psychological stress, and impaired vision, mobility, and communication. For any given situation, equipment and clothing should be selected that provide an adequate level of protection. However, over-protection, as well as under-protection, can be hazardous and should be avoided where possible.
Two basic objectives of any PPE program should be to protect the wearer from safety and health hazards, and to prevent injury to the wearer from incorrect use and/or malfunction of the PPE. To accomplish these goals, a comprehensive PPE program should include hazard identification, medical monitoring, environmental surveillance, selection, use, maintenance, and decontamination of PPE and its associated training.
The written PPE program should include policy statements, procedures, and guidelines. Copies should be made available to all employees, and a reference copy should be made available at the worksite. Technical data on equipment, maintenance manuals, relevant regulations, and other essential information should also be collected and maintained.
6. Incident command system (ICS). Paragraph 1926.65(q)(3)(ii) requires the implementation of an ICS. The ICS is an organized approach to effectively control and manage operations at an emergency incident. The individual in charge of the ICS is the senior official responding to the incident. The ICS is not much different than the “command post” approach used for many years by the fire service. During large complex fires involving several companies and many pieces of apparatus, a command post would be established. This enabled one individual to be in charge of managing the incident, rather than having several officers from different companies making separate, and sometimes conflicting, decisions. The individual in charge of the command post would delegate responsibility for performing various tasks to subordinate officers. Additionally, all communications were routed through the command post to reduce the number of radio transmissions and eliminate confusion. However, strategy, tactics, and all decisions were made by one individual.
The ICS is a very similar system, except it is implemented for emergency response to all incidents, both large and small, that involve hazardous substances.
For a small incident, the individual in charge of the ICS may perform many tasks of the ICS. There may not be any, or little, delegation of tasks to subordinates. For example, in response to a small incident, the individual in charge of the ICS, in addition to normal command activities, may become the safety officer and may designate only one employee (with proper equipment) as a back-up to provide assistance if needed. OSHA does recommend, however, that at least two employees be designated as back-up personnel since the assistance needed may include rescue.
To illustrate the operation of the ICS, the following scenario might develop during a small incident, such as an overturned tank truck with a small leak of flammable liquid.
The first responding senior officer would implement and take command of the ICS. That person would size-up the incident and determine if additional personnel and apparatus were necessary; would determine what actions to take to control the leak; and, determine the proper level of personal protective equipment. If additional assistance is not needed, the individual in charge of the ICS would implement actions to stop and control the leak using the fewest number of personnel that can effectively accomplish the tasks. The individual in charge of the ICS then would designate himself as the safety officer and two other employees as a back-up in case rescue may become necessary. In this scenario, decontamination procedures would not be necessary.
A large complex incident may require many employees and difficult, time-consuming efforts to control. In these situations, the individual in charge of the ICS will want to delegate different tasks to subordinates in order to maintain a span of control that will keep the number of subordinates, that are reporting, to a manageable level.
Delegation of task at large incidents may be by location, where the incident scene is divided into sectors, and subordinate officers coordinate activities within the sector that they have been assigned.
Delegation of tasks can also be by function. Some of the functions that the individual in charge of the ICS may want to delegate at a large incident are: medical services; evacuation; water supply; resources (equipment, apparatus); media relations; safety; and, site control (integrate activities with police for crowd and traffic control). Also for a large incident, the individual in charge of the ICS will designate several employees as back-up personnel; and a number of safety officers to monitor conditions and recommend safety precautions.
Therefore, no matter what size or complexity an incident may be, by implementing an ICS there will be one individual in charge who makes the decisions and gives directions; and, all actions, and communications are coordinated through one central point of command. Such a system should reduce confusion, improve safety, organize and coordinate actions, and should facilitate effective management of the incident.
7. Site Safety and Control Plans. The safety and security of response personnel and others in the area of an emergeny response incident site should be of primary concern to the incident commander. The use of a site safety and control plan could greatly assist those in charge of assuring the safety and health of employees on the site.
A comprehensive site safety and control plan should include the following: summary analysis of hazards on the site and a risk analysis of those hazards; site map or sketch; site work zones (clean zone, transition or decontamination zone, work or hot zone); use of the buddy system; site communications; command post or command center; standard operating procedures and safe work practices; medical assistance and triage area; hazard monitoring plan (air contaminate monitoring, etc.); decontamination procedures and area; and other relevant areas. This plan should be a part of the employer's emergency response plan or an extension of it to the specific site.
8. Medical surveillance programs. Workers handling hazardous substances may be exposed to toxic chemicals, safety hazards, biologic hazards, and radiation. Therefore, a medical surveillance program is essential to assess and monitor workers' health and fitness for employment in hazardous waste operations and during the course of work; to provide emergency and other treatment as needed; and to keep accurate records for future reference.
The Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities developed by the National Institute for Occupational Safety and Health (NIOSH), the Occupational Safety and Health Administration (OSHA), the U.S. Coast Guard (USCG), and the Environmental Protection Agency (EPA); October 1985 provides an excellent example of the types of medical testing that should be done as part of a medical surveillance program.
9. New Technology and Spill Containment Programs. Where hazardous substances may be released by spilling from a container that will expose employees to the hazards of the materials, the employer will need to implement a program to contain and control the spilled material. Diking and ditching, as well as use of absorbents like diatomaceous earth, are traditional techniques which have proven to be effective over the years. However, in recent years new products have come into the marketplace, the use of which complement and increase the effectiveness of these traditional methods. These new products also provide emergency responders and others with additional tools or agents to use to reduce the hazards of spilled materials.
These agents can be rapidly applied over a large area and can be uniformly applied or otherwise can be used to build a small dam, thus improving the workers' ability to control spilled material. These application techniques enhance the intimate contact between the agent and the spilled material allowing for the quickest effect by the agent or quickest control of the spilled material. Agents are available to solidify liquid spilled materials, to suppress vapor generation from spilled materials, and to do both. Some special agents, which when applied as recommended by the manufacturer, will react in a controlled manner with the spilled material to neutralize acids or caustics, or greatly reduce the level of hazard of the spilled material.
There are several modern methods and devices for use by emergency response personnel or others involved with spill control efforts to safely apply spill control agents to control spilled material hazards. These include portable pressurized applicators similar to hand-held portable fire extinguishing devices, and nozzle and hose systems similar to portable fire fighting foam systems which allow the operator to apply the agent without having to come into contact with the spilled material. The operator is able to apply the agent to the spilled material from a remote position.
The solidification of liquids provides for rapid containment and isolation of hazardous substance spills. By directing the agent at run-off points or at the edges of the spill, the reactant solid will automatically create a barrier to slow or stop the spread of the material. Clean-up of hazardous substances is greatly improved when solidifying agents, acid or caustic neutralizers, or activated carbon adsorbents are used. Properly applied, these agents can totally solidify liquid hazardous substances or neutralize or absorb them, which results in materials which are less hazardous and easier to handle, transport, and dispose of. The concept of spill treatment, to create less hazardous substances, will improve the safety and level of protection of employees working at spill clean-up operations or emergency response operations to spills of hazardous substances.
The use of vapor suppression agents for volatile hazardous substances, such as flammable liquids and those substances which present an inhalation hazard, is important for protecting workers. The rapid and uniform distribution of the agent over the surface of the spilled material can provide quick vapor knockdown. There are temporary and long-term foam-type agents which are effective on vapors and dusts, and activated carbon adsorption agents which are effective for vapor control and soaking-up of the liquid. The proper use of hose lines or hand-held portable pressurized applicators provides good mobility and permits the worker to deliver the agent from a safe distance without having to step into the untreated spilled material. Some of these systems can be recharged in the field to provide coverage of larger spill areas than the design limits of a single charged applicator unit. Some of the more effective agents can solidify the liquid flammable hazardous substances and at the same time elevate the flashpoint above 140 °F so the resulting substance may be handled as a nonhazardous waste material if it meets the U.S. Environmental Protection Agency's 40 CFR part 261 requirements (See particularly § 261.21).
All workers performing hazardous substance spill control work are expected to wear the proper protective clothing and equipment for the materials present and to follow the employer's established standard operating procedures for spill control. All involved workers need to be trained in the established operating procedures; in the use and care of spill control equipment; and in the associated hazards and control of such hazards of spill containment work.
These new tools and agents are the things that employers will want to evaluate as part of their new technology program. The treatment of spills of hazardous substances or wastes at an emergency incident as part of the immediate spill containment and control efforts is sometimes acceptable to EPA and a permit exception is described in 40 CFR 264.1(g)(8) and 265.1(c)(11).
Appendix D to § 1926.65—References
The following references may be consulted for further information on the subject of this standard:
1. OSHA Instruction DFO CPL 2.70—January 29, 1986, Special Emphasis Program: Hazardous Waste Sites.
2. OSHA Instruction DFO CPL 2-2.37A—January 29, 1986, Technical Assistance and Guidelines for Superfund and Other Hazardous Waste Site Activities.
3. OSHA Instruction DTS CPL 2.74—January 29, 1986, Hazardous Waste Activity Form, OSHA 175.
4. Hazardous Waste Inspections Reference Manual, U.S. Department of Labor, Occupational Safety and Health Administration, 1986.
5. Memorandum of Understanding Among the National Institute for Occupational Safety and Health, the Occupational Safety and Health Administration, the United States Coast Guard, and the United States Environmental Protection Agency, Guidance for Worker Protection During Hazardous Waste Site Investigations and Clean-up and Hazardous Substance Emergencies. December 18, 1980.
6. National Priorities List, 1st Edition, October 1984; U.S. Environmental Protection Agency, Revised periodically.
7. The Decontamination of Response Personnel, Field Standard Operating Procedures (F.S.O.P.) 7; U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Hazardous Response Support Division, December 1984.
8. Preparation of a Site Safety Plan, Field Standard Operating Procedures (F.S.O.P.) 9; U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Hazardous Response Support Division, April 1985.
9. Standard Operating Safety Guidelines; U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Hazardous Response Support Division, Environmental Response Team; November 1984.
10. Occupational Safety and Health Guidance Manual for Hazardous Waste Site Activities, National Institute for Occupational Safety and Health (NIOSH), Occupational Safety and Health Administration (OSHA), U.S. Coast Guard (USCG), and Environmental Protection Agency (EPA); October 1985.
11. Protecting Health and Safety at Hazardous Waste Sites: An Overview, U.S. Environmental Protection Agency, EPA/625/9-85/006; September 1985.
12. Hazardous Waste Sites and Hazardous Substance Emergencies, NIOSH Worker Bulletin, U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health; December 1982.
13. Personal Protective Equipment for Hazardous Materials Incidents: A Selection Guide; U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health; October 1984.
14. Fire Service Emergency Management Handbook, International Association of Fire Chiefs Foundation, 101 East Holly Avenue, Unit 10B, Sterling, VA 22170, January 1985.
15. Emergency Response Guidebook, U.S Department of Transportation, Washington, DC, 1987.
16. Report to the Congress on Hazardous Materials Training, Planning and Preparedness, Federal Emergency Management Agency, Washington, DC, July 1986.
17. Workbook for Fire Command, Alan V. Brunacini and J. David Beageron, National Fire Protection Association, Batterymarch Park, Quincy, MA 02269, 1985.
18. Fire Command, Alan V. Brunacini, National Fire Protection Association, Batterymarch Park,, Quincy, MA 02269, 1985.
19. Incident Command System, Fire Protection Publications, Oklahoma State University, Stillwater, OK 74078, 1983.
20. Site Emergency Response Planning, Chemical Manufacturers Association, Washington, DC 20037, 1986.
21. Hazardous Materials Emergency Planning Guide, NRT-1, Environmental Protection Agency, Washington, DC, March 1987.
22. Community Teamwork: Working Together to Promote Hazardous Materials Transportation Safety. U.S. Department of Transportation, Washington, DC, May 1983.
23. Disaster Planning Guide for Business and Industry, Federal Emergency Management Agency, Publication No. FEMA 141, August 1987.
Appendix E to § 1926.65—Training Curriculum Guidelines
The following non-mandatory general criteria may be used for assistance in developing site-specific training curriculum used to meet the training requirements of 29 CFR 1926.65(e); 29 CFR 1926.65(p)(7), (p)(8)(iii); and 29 CFR 1926.65(q)(6), (q)(7), and (q)(8). These are generic guidelines and they are not presented as a complete training curriculum for any specific employer. Site-specific training programs must be developed on the basis of a needs assessment of the hazardous waste site, RCRA/TSDF, or emergency response operation in accordance with 29 CFR 1926.65.
It is noted that the legal requirements are set forth in the regulatory text of § 1926.65. The guidance set forth here presents a highly effective program that in the areas covered would meet or exceed the regulatory requirements. In addition, other approaches could meet the regulatory requirements.
Suggested General Criteria
Definitions:
Competent means possessing the skills, knowledge, experience, and judgment to perform assigned tasks or activities satisfactorily as determined by the employer.
Demonstration means the showing by actual use of equipment or procedures.
Hands-on training means training in a simulated work environment that permits each student to have experience performing tasks, making decisions, or using equipment appropriate to the job assignment for which the training is being conducted.
Initial training means training required prior to beginning work.
Lecture means an interactive discourse with a class lead by an instructor.
Proficient means meeting a stated level of achievement.
Site-specific means individual training directed to the operations of a specific job site.
Training hours means the number of hours devoted to lecture, learning activities, small group work sessions, demonstration, evaluations, or hands-on experience.
Suggested Core Criteria:
1. Training facility. The training facility should have available sufficient resources, equipment, and site locations to perform didactic and hands-on training when appropriate. Training facilities should have sufficient organization, support staff, and services to conduct training in each of the courses offered.
2. Training Director. Each training program should be under the direction of a training director who is responsible for the program. The Training Director should have a minimum of two years of employee education experience.
3. Instructors. Instructors should be deem competent on the basis of previous documented experience in their area of instruction, successful completion of a “train-the-trainer” program specific to the topics they will teach, and an evaluation of instructional competence by the Training Director.
Instructors should be required to maintain professional competency by participating in continuing education or professional development programs or by completing successfully an annual refresher course and having an annual review by the Training Director.
The annual review by the Training Director should include observation of an instructor's delivery, a review of those observations with the trainer, and an analysis of any instructor or class evaluations completed by the students during the previous year.
4. Course materials. The Training Director should approve all course materials to be used by the training provider. Course materials should be reviewed and updated at least annually. Materials and equipment should be in good working order and maintained properly.
All written and audio-visual materials in training curricula should be peer reviewed by technically competent outside reviewers or by a standing advisory committee.
Reviews should possess expertise in the following disciplines were applicable: occupational health, industrial hygiene and safety, chemical/environmental engineering, employee education, or emergency response. One or more of the peer reviewers should be a employee experienced in the work activities to which the training is directed.
5. Students. The program for accepting students should include:
a. Assurance that the student is or will be involved in work where chemical exposures are likely and that the student possesses the skills necessary to perform the work.
b. A policy on the necessary medical clearance.
6. Ratios. Student-instructor ratios should not exceed 30 students per instructor. Hands-on activity requiring the use of personal protective equipment should have the following student-instructor ratios. For Level C or Level D personal protective equipment the ratio should be 10 students per instructor. For Level A or Level B personal protective equipment the ratio should be 5 students per instructor.
7. Proficiency assessment. Proficiency should be evaluated and documented by the use of a written assessment and a skill demonstration selected and developed by the Training Director and training staff. The assessment and demonstration should evaluate the knowledge and individual skills developed in the course of training. The level of minimum achievement necessary for proficiency shall be specified in writing by the Training Director.
If a written test is used, there should be a minimum of 50 questions. If a written test is used in combination with a skills demonstration, a minimum of 25 questions should be used. If a skills demonstration is used, the tasks chosen and the means to rate successful completion should be fully documented by the Training Director.
The content of the written test or of the skill demonstration shall be relevant to the objectives of the course. The written test and skill demonstration should be updated as necessary to reflect changes in the curriculum and any update should be approved by the Training Director.
The proficiency assessment methods, regardless of the approach or combination of approaches used, should be justified, document and approved by the Training Director.
The proficiency of those taking the additional courses for supervisors should be evaluated and document by using proficiency assessment methods acceptable to the Training Director. These proficiency assessment methods must reflect the additional responsibilities borne by supervisory personnel in hazardous waste operations or emergency response.
8. Course certificate. Written documentation should be provided to each student who satisfactorily completes the training course. The documentation should include:
a. Student's name.
b. Course title.
c. Course date.
d. Statement that the student has successfully completed the course.
e. Name and address of the training provider.
f. An individual identification number for the certificate.
g. List of the levels of personal protective equipment used by the student to complete the course.
This documentation may include a certificate and an appropriate wallet-sized laminated card with a photograph of the student and the above information. When such course certificate cards are used, the individual identification number for the training certificate should be shown on the card.
9. Recordkeeping. Training providers should maintain records listing the dates courses were presented, the names of the individual course attenders, the names of those students successfully completing each course, and the number of training certificates issued to each successful student. These records should be maintained for a minimum of five years after the date an individual participated in a training program offered by the training provider. These records should be available and provided upon the student's request or as mandated by law.
10. Program quality control. The Training Director should conduct or direct an annual written audit of the training program. Program modifications to address deficiencies, if any, should be documented, approved, and implemented by the training provider. The audit and the program modification documents should be maintained at the training facility.
Suggested Program Quality Control Criteria
Factors listed here are suggested criteria for determining the quality and appropriateness of employee health and safety training for hazardous waste operations and emergency response.
A. Training Plan.
Adequacy and appropriateness of the training program's curriculum development, instructor training, distribution of course materials, and direct student training should be considered, including
1. The duration of training, course content, and course schedules/agendas;
2. The different training requirements of the various target populations, as specified in the appropriate generic training curriculum;
3. The process for the development of curriculum, which includes appropriate technical input, outside review, evaluation, program pretesting.
4. The adequate and appropriate inclusion of hands-on, demonstration, and instruction methods;
5. Adequate monitoring of student safety, progress, and performance during the training.
B. Program management, Training Director, staff, and consultants.
Adequacy and appropriateness of staff performance and delivering an effective training program should be considered, including
1. Demonstration of the training director's leadership in assuring quality of health and safety training.
2. Demonstration of the competency of the staff to meet the demands of delivering high quality hazardous waste employee health and safety training.
3. Organization charts establishing clear lines of authority.
4. Clearly defined staff duties including the relationship of the training staff to the overall program.
5. Evidence that the training organizational structure suits the needs of the training program.
6. Appropriateness and adequacy of the training methods used by the instructors.
7. Sufficiency of the time committed by the training director and staff to the training program.
8. Adequacy of the ratio of training staff to students.
9. Availability and commitment of the training program of adequate human and equipment resources in the areas of
a. Health effects,
b. Safety,
c. Personal protective equipment (PPE),
d. Operational procedures,
e. Employee protection practices/procedures.
10. Appropriateness of management controls.
11. Adequacy of the organization and appropriate resources assigned to assure appropriate training.
12. In the case of multiple-site training programs, adequacy of satellite centers management.
C. Training facilities and resources.
Adequacy and appropriateness of the facilities and resources for supporting the training program should be considered, including,
1. Space and equipment to conduct the training.
2. Facilities for representative hands-on training.
3. In the case of multiple-site programs, equipment and facilities at the satellite centers.
4. Adequacy and appropriateness of the quality control and evaluations program to account for instructor performance.
5. Adequacy and appropriateness of the quality control and evaluation program to ensure appropriate course evaluation, feedback, updating, and corrective action.
6. Adequacy and appropriateness of disciplines and expertise being used within the quality control and evaluation program.
7. Adequacy and appropriateness of the role of student evaluations to provide feedback for training program improvement.
D. Quality control and evaluation.
Adequacy and appropriateness of quality control and evaluation plans for training programs should be considered, including:
1. A balanced advisory committee and/or competent outside reviewers to give overall policy guidance;
2. Clear and adequate definition of the composition and active programmatic role of the advisory committee or outside reviewers.
3. Adequacy of the minutes or reports of the advisory committee or outside reviewers' meetings or written communication.
4. Adequacy and appropriateness of the quality control and evaluations program to account for instructor performance.
5. Adequacy and appropriateness of the quality control and evaluation program to ensure appropriate course evaluation, feedback, updating, and corrective action.
6. Adequacy and appropriateness of disciplines and expertise being used within the quality control and evaluation program.
7. Adequacy and appropriateness of the role of student evaluations to provide feedback for training program improvement.
E. Students
Adequacy and appropriateness of the program for accepting students should be considered, including
1. Assurance that the student already possess the necessary skills for their job, including necessary documentation.
2. Appropriateness of methods the program uses to ensure that recruits are capable of satisfactorily completing training.
3. Review and compliance with any medical clearance policy.
F. Institutional Environment and Administrative Support. The adequacy and appropriateness of the institutional environment and administrative support system for the training program should be considered, including
1. Adequacy of the institutional commitment to the employee training program.
2. Adequacy and appropriateness of the administrative structure and administrative support.
G. Summary of Evaluation Questions Key questions for evaluating the quality and appropriateness of an overall training program should include the following:
1. Are the program objectives clearly stated?
2. Is the program accomplishing its objectives?
3. Are appropriate facilities and staff available?
4. Is there an appropriate mix of classroom, demonstration, and hands-on training?
5. Is the program providing quality employee health and safety training that fully meets the intent of regulatory requirements?
6. What are the program's main strengths?
7. What are the program's main weaknesses?
8. What is recommended to improve the program?
9. Are instructors instructing according to their training outlines?
10. Is the evaluation tool current and appropriate for the program content?
11. Is the course material current and relevant to the target group?
Suggested Training Curriculum Guidelines
The following training curriculum guidelines are for those operations specifically identified in 29 CFR 1926.65 as requiring training. Issues such as qualifications of instructors, training certification, and similar criteria appropriate to all categories of operations addressed in 1926.65 have been covered in the preceding section and are not re-addressed in each of the generic guidelines. Basic core requirements for training programs that are addressed include
1. General Hazardous Waste Operations
2. RCRA operations—Treatment, storage, and disposal facilities.
3. Emergency Response.
A. General Hazardous Waste Operations and Site-specific Training 1. Off-site training.
Minimum training course content for hazardous waste operations, required by 29 CFR 1926.65(e), should include the following topics or procedures:
a. Regulatory knowledge.
b. Technical knowledge.
c. Technical skills.
d. Additional suggested items.
2. Refresher training. The 8-hour annual refresher training required in 29 CFR 1926.65(e)(8) should be conducted by qualified training providers. Refresher training should include at a minimum the following topics and procedures:
3. On-site training. a. The employer should provide employees engaged in hazardous waste site activities with information and training prior to initial assignment into their work area, as follows:
b. The employer should provide hazardous waste employees information and training and should provide a review and access to the site safety and plan as follows:
c. The employer should provide hazardous waste employees information and training on personal protective equipment used at the site, such as the following:
to be used based upon known or anticipated site hazards.
limitations of materials and construction; limitations during temperature extremes, heat stress, and other appropriate medical considerations; use and limitations of respirator equipment as well as documentation procedures as outlined in 29 CFR 1910.134.
inspection procedures prior to, during, and after use.
donning and doffing procedures.
decontamination and disposal procedures.
maintenance and storage.
d. The employer should instruct the employee about the site medical surveillance program relative to the particular site, including
e. The employees will review and discuss the site safety plan as part of the training program. The location of the site safety plan and all written programs should be discussed with employees including a discussion of the mechanisms for access, review, and references described.
B. RCRA Operations Training for Treatment, Storage and Disposal Facilities.
1. As a minimum, the training course required in 29 CFR 1926.65 (p) should include the following topics:
2. The individual employer should provide hazardous waste employees with information and training prior to an employee's initial assignment into a work area. The training and information should cover the following topics:
C. Emergency response training.
Federal OSHA standards in 29 CFR 1926.65(q) are directed toward private sector emergency responders. Therefore, the guidelines provided in this portion of the appendix are directed toward that employee population. However, they also impact indirectly through State OSHA or USEPA regulations some public sector emergency responders. Therefore, the guidelines provided in this portion of the appendix may be applied to both employee populations.
States with OSHA state plans must cover their employees with regulations at least as effective as the Federal OSHA standards. Public employees in states without approved state OSHA programs covering hazardous waste operations and emergency response are covered by the U.S. EPA under 40 CFR 311, a regulation virtually identical to § 1926.65.
Since this is a non-mandatory appendix and therefore not an enforceable standard, OSHA recommends that those employers, employees or volunteers in public sector emergency response organizations outside Federal OSHA jurisdiction consider the following criteria in developing their own training programs. A unified approach to training at the community level between emergency response organizations covered by Federal OSHA and those not covered directly by Federal OSHA can help ensure an effective community response to the release or potential release of hazardous substances in the community.
a. General considerations.
Emergency response organizations are required to consider the topics listed in § 1926.65(q)(6). Emergency response organizations may use some or all of the following topics to supplement those mandatory topics when developing their response training programs. Many of the topics would require an interaction between the response provider and the individuals responsible for the site where the response would be expected.
b. Suggested criteria for specific courses.
Department of Transportation's Emergency Response Guidebook (ERG) and familiarization with OSHA standard 29 CFR 1926.60.
Department of Transportation's Emergency Response Guidebook (ERG), manufacturer safety data sheets, CHEMTREC/CANUTEC, shipper or manufacturer contacts and other relevant sources of information addressing hazardous substance releases. Familiarization with OSHA standard 29 CFR 1926.60.
The incident commander is the individual who, at any one time, is responsible for and in control of the response effort. This individual is the person responsible for the direction and coordination of the response effort. An incident commander's position should be occupied by the most senior, appropriately trained individual present at the response site. Yet, as necessary and appropriate by the level of response provided, the position may be occupied by many individuals during a particular response as the need for greater authority, responsibility, or training increases. It is possible for the first responder at the awareness level to assume the duties of incident commander until a more senior and appropriately trained individual arrives at the response site.
Therefore, any emergency responder expected to perform as an incident commander should be trained to fulfill the obligations of the position at the level of response they will be providing including the following:
[58 FR 35129, June 30, 1993, as amended at 59 FR 43275, Aug. 22, 1994: 61 FR 5510, Feb. 13, 1996; 77 FR 17890, Mar. 26, 2012; 78 FR 9315, Feb. 8, 2013; 85 FR 8736, Feb. 18, 2020]
Aerated powders shall mean any powdered material used as a coating material which shall be fluidized within a container by passing air uniformly from below. It is common practice to fluidize such materials to form a fluidized powder bed and then dip the part to be coated into the bed in a manner similar to that used in liquid dipping. Such beds are also used as sources for powder spray operations.
Any area in which dangerous quantities of flammable vapors or mists, or combustible residues, dusts, or deposits are present due to the operation of spraying processes.
A power-ventilated structure provided to enclose or accommodate a spraying operation to confine and limit the escape of spray, vapor, and residue, and to safely conduct or direct them to an exhaust system.
A spray booth equipped with a water washing system designed to minimize dusts or residues entering exhaust ducts and to permit the recovery of overspray finishing material.
A spray booth not equipped with a water washing system as described in paragraph (a)(4) of this section. A dry spray booth may be equipped with
A container holding powder coating material which is aerated from below so as to form an air-supported expanded cloud of such material through which the preheated object to be coated is immersed and transported.
A container holding powder coating material which is aerated from below so as to form an air-supported expanded cloud of such material which is electrically charged with a charge opposite to the charge of the object to be coated; such object is transported, through the container immediately above the charged and aerated materials in order to be coated.
Shall mean approved and listed by a nationally recognized testing laboratory.
See “approved” in paragraph (a)(8) of this section.
Spray booths shall be substantially constructed of steel, securely and rigidly supported, or of concrete or masonry except that aluminum or other substantial noncombustible material may be used for intermittent or low volume spraying. Spray booths shall be designed to sweep air currents toward the exhaust outlet.
The interior surfaces of spray booths shall be smooth and continuous without edges and otherwise designed to prevent pocketing of residues and facilitate cleaning and washing without injury.
The floor surface of a spray booth and operator's working area, if combustible, shall be covered with noncombustible material of such character as to facilitate the safe cleaning and removal of residues.
Distribution or baffle plates, if installed to promote an even flow of air through the booth or cause the deposit of overspray before it enters the exhaust duct, shall be of noncombustible material and readily removable or accessible on both sides for cleaning. Such plates shall not be located in exhaust ducts.
In conventional dry type spray booths, overspray dry filters or filter rolls, if installed, shall conform to the following:
Each spray booth having a frontal area larger than 9 square feet shall have a metal deflector or curtain not less than 2 1/2 inches (5.35 cm) deep installed at the upper outer edge of the booth over the opening.
Where conveyors are arranged to carry work into or out of spray booths, the openings therefor shall be as small as practical.
Each spray booth shall be separated from other operations by not less than 3 feet (0.912 m), or by a greater distance, or by such partition or wall as to reduce the danger from juxtaposition of hazardous operations. See also paragraph (c)(1) of this section.
Spray booths shall be so installed that all portions are readily accessible for cleaning. A clear space of not less than 3 feet (0.912 m) on all sides shall be kept free from storage or combustible construction.
When spraying areas are illuminated through glass panels or other transparent materials, only fixed lighting units shall be used as a source of illumination. Panels shall effectively isolate the spraying area from the area in which the lighting unit is located, and shall be of a noncombustible material of such a nature or so protected that breakage will be unlikely. Panels shall be so arranged that normal accumulations of residue on the exposed surface of the panel will not be raised to a dangerous temperature by radiation or conduction from the source of illumination.
All electrical equipment, open flames and other sources of ignition shall conform to the requirements of this paragraph, except as follows:
There shall be no open flame or spark producing equipment in any spraying area nor within 20 feet (6.08 m) thereof, unless separated by a partition.
Space-heating appliances, steampipes, or hot surfaces shall not be located in a spraying area where deposits of combustible residues may readily accumulate.
Electrical wiring and equipment shall conform to the provisions of this paragraph and shall otherwise be in accordance with subpart S of this part.
Unless specifically approved for locations containing both deposits of readily ignitable residue and explosive vapors, there shall be no electrical equipment in any spraying area, whereon deposits of combustible residues may readily accumulate, except wiring in rigid conduit or in boxes or fittings containing no taps, splices, or terminal connections.
Electrical wiring and equipment not subject to deposits of combustible residues but located in a spraying area as herein defined shall be of explosion-proof type approved for Class I, group D locations and shall otherwise conform to the provisions of subpart S of this part, for Class I, Division 1, Hazardous Locations. Electrical wiring, motors, and other equipment outside of but within 20 feet (6.08 m) of any spraying area, and not separated therefrom by partitions, shall not produce sparks under normal operating conditions and shall otherwise conform to the provisions of subpart S of this part for Class I, Division 2 Hazardous Locations.
Electric lamps outside of, but within 20 feet (6.08 m) of any spraying area, and not separated therefrom by a partition, shall be totally enclosed to prevent the falling of hot particles and shall be protected from mechanical injury by suitable guards or by location.
Portable electric lamps shall not be used in any spraying area during spraying operations. Portable electric lamps, if used during cleaning or repairing operations, shall be of the type approved for hazardous Class I locations.
Ventilating and exhaust systems shall be in accordance with the Standard for Blower and Exhaust Systems for Vapor Removal, NFPA No. 91-1961, where applicable and shall also conform to the provisions of this section.
All spraying areas shall be provided with mechanical ventilation adequate to remove flammable vapors, mists, or powders to a safe location and to confine and control combustible residues so that life is not endangered. Mechanical ventilation shall be kept in operation at all times while spraying operations are being conducted and for a sufficient time thereafter to allow vapors from drying coated articles and drying finishing material residue to be exhausted.
Each spray booth shall have an independent exhaust duct system discharging to the exterior of the building, except that multiple cabinet spray booths in which identical spray finishing material is used with a combined frontal area of not more than 18 square feet may have a common exhaust. If more than one fan serves one booth, all fans shall be so interconnected that one fan cannot operate without all fans being operated.
The fan-rotating element shall be nonferrous or nonsparking or the casing shall consist of or be lined with such material. There shall be ample clearance between the fan-rotating element and the fan casing to avoid a fire by friction, necessary allowance being made for ordinary expansion and loading to prevent contact between moving parts and the duct or fan housing. Fan blades shall be mounted on a shaft sufficiently heavy to maintain perfect alignment even when the blades of the fan are heavily loaded, the shaft preferably to have bearings outside the duct and booth. All bearings shall be of the self-lubricating type, or lubricated from the outside duct.
Electric motors driving exhaust fans shall not be placed inside booths or ducts. See also paragraph (c) of this section.
Belts shall not enter the duct or booth unless the belt and pulley within the duct or booth are thoroughly enclosed.
Exhaust ducts shall be constructed of steel and shall be substantially supported. Exhaust ducts without dampers are preferred; however, if dampers are installed, they shall be maintained so that they will be in a full open position at all times the ventilating system is in operation.
| ( a ) 28-gage sheet metal on 1/4-inch asbestos mill board | 12 inches (30.48 cm). |
|---|---|
| ( b ) 28-gage sheet metal on 1/8-inch asbestos mill board spaced out 1 inch (2.54 cm) on noncombustible spacers | 9 inches (22.86 cm). |
| ( c ) 22-gage sheet metal on 1-inch rockwool batts reinforced with wire mesh or the equivalent | 3 inches (7.62 cm). |
| ( d ) Where ducts are protected with an approved automatic sprinkler system, properly maintained, the clearance required in paragraph (d)(7)(i) of this section may be reduced to 6 inches (15.24 cm) |
Unless the spray booth exhaust duct terminal is from a water-wash spray booth, the terminal discharge point shall be not less than 6 feet from any combustible exterior wall or roof nor discharge in the direction of any combustible construction or unprotected opening in any noncombustible exterior wall within 25 feet (7.6 m).
Air exhaust from spray operations shall not be directed so that it will contaminate makeup air being introduced into the spraying area or other ventilating intakes, nor directed so as to create a nuisance. Air exhausted from spray operations shall not be recirculated.
When necessary to facilitate cleaning, exhaust ducts shall be provided with an ample number of access doors.
Air intake openings to rooms containing spray finishing operations shall be adequate for the efficient operation of exhaust fans and shall be so located as to minimize the creation of dead air pockets.
Freshly sprayed articles shall be dried only in spaces provided with adequate ventilation to prevent the formation of explosive vapors. In the event adequate and reliable ventilation is not provided such drying spaces shall be considered a spraying area.
Where installation and use of electrostatic spraying equipment is used, such installation and use shall conform to all other paragraphs of this section, and shall also conform to the requirements of this paragraph.
Electrostatic apparatus and devices used in connection with coating operations shall be of approved types.
Transformers, power packs, control apparatus, and all other electrical portions of the equipment, with the exception of high-voltage grids, electrodes, and electrostatic atomizing heads and their connections, shall be located outside of the spraying area, or shall otherwise conform to the requirements of paragraph (c) of this section.
Electrodes and electrostatic atomizing heads shall be adequately supported in permanent locations and shall be effectively insulated from the ground. Electrodes and electrostatic atomizing heads which are permanently attached to their bases, supports, or reciprocators, shall be deemed to comply with this section. Insulators shall be nonporous and noncombustible.
High-voltage leads to electrodes shall be properly insulated and protected from mechanical injury or exposure to destructive chemicals. Electrostatic atomizing heads shall be effectively and permanently supported on suitable insulators and shall be effectively guarded against accidental contact or grounding. An automatic means shall be provided for grounding the electrode system when it is electrically deenergized for any reason. All insulators shall be kept clean and dry.
A safe distance shall be maintained between goods being painted and electrodes or electrostatic atomizing heads or conductors of at least twice the sparking distance. A suitable sign indicating this safe distance shall be conspicuously posted near the assembly.
Goods being painted using this process are to be supported on conveyors. The conveyors shall be so arranged as to maintain safe distances between the goods and the electrodes or electrostatic atomizing heads at all times. Any irregularly shaped or other goods subject to possible swinging or movement shall be rigidly supported to prevent such swinging or movement which would reduce the clearance to less than that specified in paragraph (e)(6) of this section.
This process is not acceptable where goods being coated are manipulated by hand. When finishing materials are applied by electrostatic equipment which is manipulated by hand, see paragraph (f) of this section for applicable requirements.
Electrostatic apparatus shall be equipped with automatic controls which will operate without time delay to disconnect the power supply to the high voltage transformer and to signal the operator under any of the following conditions:
Adequate booths, fencing, railings, or guards shall be so placed about the equipment that they, either by their location or character or both, assure that a safe isolation of the process is maintained from plant storage or personnel. Such railings, fencing, and guards shall be of conducting material, adequately grounded.
Where electrostatic atomization is used the spraying area shall be so ventilated as to insure safe conditions from a fire and health standpoint.
All areas used for spraying, including the interior of the booth, shall be protected by automatic sprinklers where this protection is available. Where this protection is not available, other approved automatic extinguishing equipment shall be provided.
This paragraph shall apply to any equipment using electrostatically charged elements for the atomization and/or, precipitation of materials for coatings on articles, or for other similar purposes in which the atomizing device is hand held and manipulated during the spraying operation.
Electrostatic hand spraying equipment shall conform with the other provisions of this section.
Electrostatic hand spray apparatus and devices used in connection with coating operations shall be of approved types. The high voltage circuits shall be designed so as to not produce a spark of sufficient intensity to ignite any vapor-air mixtures nor result in appreciable shock hazard upon coming in contact with a grounded object under all normal operating conditions. The electrostatically charged exposed elements of the handgun shall be capable of being energized only by a switch which also controls the coating material supply.
Transformers, powerpacks, control apparatus, and all other electrical portions of the equipment, with the exception of the handgun itself and its connections to the power supply shall be located outside of the spraying area or shall otherwise conform to the requirements of paragraph (c) of this section.
The handle of the spraying gun shall be electrically connected to ground by a metallic connection and to be so constructed that the operator in normal operating position is in intimate electrical contact with the grounded handle.
All electrically conductive objects in the spraying area shall be adequately grounded. This requirement shall apply to paint containers, wash cans, and any other objects or devices in the area. The equipment shall carry a prominent permanently installed warning regarding the necessity for this grounding feature.
Objects being painted or coated shall be maintained in metallic contact with the conveyor or other grounded support. Hooks shall be regularly cleaned to insure this contact and areas of contact shall be sharp points or knife edges where possible. Points of support of the object shall be concealed from random spray where feasible and where the objects being sprayed are supported from a conveyor, the point of attachment to the conveyor shall be so located as to not collect spray material during normal operation.
The electrical equipment shall be so interlocked with the ventilation of the spraying area that the equipment cannot be operated unless the ventilation fans are in operation.
The spraying operation shall take place within a spray area which is adequately ventilated to remove solvent vapors released from the operation.
Drying, curing, or fusion apparatus in connection with spray application of flammable and combustible finishes shall conform to the Standard for Ovens and Furnaces, NFPA 86A-1969, where applicable and shall also conform with the following requirements of this paragraph.
Spray booths, rooms, or other enclosures used for spraying operations shall not alternately be used for the purpose of drying by any arrangement which will cause a material increase in the surface temperature of the spray booth, room, or enclosure.
Except as specifically provided in paragraph (g)(4) of this section, drying, curing, or fusion units utilizing a heating system having open flames or which may produce sparks shall not be installed in a spraying area, but may be installed adjacent thereto when equipped with an interlocked ventilating system arranged to:
Automobile refinishing spray booths or enclosures, otherwise installed and maintained in full conformity with this section, may alternately be used for drying with portable electrical infrared drying apparatus when conforming with the following:
[58 FR 35149, June 30, 1993]
Protective equipment, including personal protective equipment for eyes, face, head, and extremities, protective clothing, respiratory devices, and protective shields and barriers, shall be provided, used, and maintained in a sanitary and reliable condition wherever it is necessary by reason of hazards of processes or environment, chemical hazards, radiological hazards, or mechanical irritants encountered in a manner capable of causing injury or impairment in the function of any part of the body through absorption, inhalation or physical contact.
Where employees provide their own protective equipment, the employer shall be responsible to assure its adequacy, including proper maintenance, and sanitation of such equipment.
Employers must ensure that all personal protective equipment:
[58 FR 35152, June 30, 1993, as amended at 72 FR 64429, Nov. 15, 2007; 89 FR 100346, Dec. 12, 2024]
Safety-toe footwear for employees shall meet the requirements and specifications in American National Standard for Men's Safety-Toe Footwear, Z41.1-1967.
[58 FR 35152, June 30, 1993]
Insulating equipment used for the protection of employees shall be capable of withstanding, without failure, the voltages that may be imposed upon it.
Electrical protective equipment shall be maintained in a safe, reliable condition.
The following specific requirements apply to rubber insulating blankets, rubber insulating covers, rubber insulating line hose, rubber insulating gloves, and rubber insulating sleeves:
Swelling, softening, hardening, or becoming sticky or inelastic.
| Class of equipment | Proof-test voltage rms V | Maximum proof-test current, mA (gloves only) | |||
|---|---|---|---|---|---|
| 280-mm (11-in) glove | 360-mm (14-in) glove | 410-mm (16-in) glove | 460-mm (18-in) glove | ||
| 00 | 2,500 | 8 | 12 | ||
| 0 | 5,000 | 8 | 12 | 14 | 16 |
| 1 | 10,000 | 14 | 16 | 18 | |
| 2 | 20,000 | 16 | 18 | 20 | |
| 3 | 30,000 | 18 | 20 | 22 | |
| 4 | 40,000 | 22 | 24 |
| Class of equipment | Proof-test voltage |
|---|---|
| 00 | 10,000 |
| 0 | 20,000 |
| 1 | 40,000 |
| 2 | 50,000 |
| 3 | 60,000 |
| 4 | 70,000 |
| Note: The dc voltages listed in this table are not appropriate for proof testing rubber insulating line hose or covers. For this equipment, dc proof tests shall use a voltage high enough to indicate that the equipment can be safely used at the voltages listed in Table E-4. See ASTM D1050-05 (2011) and ASTM D1049-98 (2010) for further information on proof tests for rubber insulating line hose and covers, respectively. |
| Class of glove | AC proof test | DC proof test | ||
|---|---|---|---|---|
| mm | in | mm | in | |
| 00 | 38 | 1.5 | 38 | 1.5 |
| 0 | 38 | 1.5 | 38 | 1.5 |
| 1 | 38 | 1.5 | 51 | 2.0 |
| 2 | 64 | 2.5 | 76 | 3.0 |
| 3 | 89 | 3.5 | 102 | 4.0 |
| 4 | 127 | 5.0 | 153 | 6.0 |
| 1 The water level is given as the clearance from the reinforced edge of the glove to the water line, with a tolerance of ±13 mm. (±0.5 in.). | ||||
| 2 If atmospheric conditions make the specified clearances impractical, the clearances may be increased by a maximum of 25 mm. (1 in.). |
| Class of equipment | Maximum use voltage 1 AC rms | Retest voltage 2 AC rms | Retest voltage 2 DC avg |
|---|---|---|---|
| 00 | 500 | 2,500 | 10,000 |
| 0 | 1,000 | 5,000 | 20,000 |
| 1 | 7,500 | 10,000 | 40,000 |
| 2 | 17,000 | 20,000 | 50,000 |
| 3 | 26,500 | 30,000 | 60,000 |
| 4 | 36,000 | 40,000 | 70,000 |
| 1 The maximum use voltage is the ac voltage (rms) classification of the protective equipment that designates the maximum nominal design voltage of the energized system that may be safely worked. The nominal design voltage is equal to the phase-to-phase voltage on multiphase circuits. However, the phase-to-ground potential is considered to be the nominal design voltage if: | |||
| (1) There is no multiphase exposure in a system area and the voltage exposure is limited to the phase-to-ground potential, or | |||
| (2) The electric equipment and devices are insulated or isolated or both so that the multiphase exposure on a grounded wye circuit is removed. | |||
| 2 The proof-test voltage shall be applied continuously for at least 1 minute, but no more than 3 minutes. |
| Type of equipment | When to test |
|---|---|
| Rubber insulating line hose | Upon indication that insulating value is suspect and after repair. |
| Rubber insulating covers | Upon indication that insulating value is suspect and after repair. |
| Rubber insulating blankets | Before first issue and every 12 months thereafter; 1 upon indication that insulating value is suspect; and after repair. |
| Rubber insulating gloves | Before first issue and every 6 months thereafter; 1 upon indication that insulating value is suspect; after repair; and after use without protectors. |
| Rubber insulating sleeves | Before first issue and every 12 months thereafter; 1 upon indication that insulating value is suspect; and after repair. |
| 1 If the insulating equipment has been electrically tested but not issued for service, the insulating equipment may not be placed into service unless it has been electrically tested within the previous 12 months. |
[79 FR 20693, Apr. 11, 2014]
will deem any head protection device that the employer demonstrates is at least as effective as a head protection device constructed in accordance with one of the consensus standards identified in paragraph (b)(1) of this section to be in compliance with the requirements of this section.
[44 FR 8577, Feb. 9, 1979, as amended at 77 FR 37600, June 22, 2012; 77 FR 42988, July 23, 2012]
Z87.1-2010, Occupational and Educational Personal Eye and Face Protection Devices, incorporated by reference in § 1926.6;
Z87.1-2003, Occupational and Educational Personal Eye and Face Protection Devices, incorporated by reference in § 1926.6; or
Z87.1-1989 (R-1998), Practice for Occupational and Educational Eye and Face Protection, incorporated by reference in § 1926.6;
| Welding operation | Shade number |
|---|---|
| Shielded metal-arc welding 1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes | 10 |
| Gas-shielded arc welding (nonferrous) 1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes | 11 |
| Gas-shielded arc welding (ferrous) 1/16-, 3/32-, 1/8-, 5/32-inch diameter electrodes | 12 |
| Shielded metal-arc welding 3/16-, 7/32-, 1/4-inch diameter electrodes | 12 |
| 5/16-, 3/8-inch diameter electrodes | 14 |
| Atomic hydrogen welding | 10-14 |
| Carbon-arc welding | 14 |
| Soldering | 2 |
| Torch brazing | 3 or 4 |
| Light cutting, up to 1 inch | 3 or 4 |
| Medium cutting, 1 inch to 6 inches | 4 or 5 |
| Heavy cutting, over 6 inches | 5 or 6 |
| Gas welding (light), up to 1/8-inch | 4 or 5 |
| Gas welding (medium), 1/8-inch to 1/2-inch | 5 or 6 |
| Gas welding (heavy), over 1/2-inch | 6 or 8 |
| Intensity, CW maximum power density (watts/cm 2 ) | Attenuation | |
|---|---|---|
| Optical density (O.D.) | Attenuation factor | |
| 10 −2 | 5 | 10 5 |
| 10 −1 | 6 | 10 6 |
| 1.0 | 7 | 10 7 |
| 10.0 | 8 | 10 8 |
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35160, June 30, 1993; 81 FR 16092, Mar. 25, 2016]
[63 FR 1297; Jan. 8, 1998]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 84 FR 21577, May 14, 2019]
means optical density and refers to the light refractive characteristics of a lens.
[44 FR 8577, Feb. 9, 1979]
-inch diameter garden-type hose line, not to exceed 100 feet in length and equipped with a nozzle, may be substituted for a 2A-rated fire extinguisher, providing it is capable of discharging a minimum of 5 gallons per minute with a minimum hose stream range of 30 feet horizontally. The garden-type hose lines shall be mounted on conventional racks or reels. The number and location of hose racks or reels shall be such that at least one hose stream can be applied to all points in the area.
In all structures in which standpipes are required, or where standpipes exist in structures being altered, they shall be brought up as soon as applicable laws permit, and shall be maintained as construction progresses in such a manner that they are always ready for fire protection use. The standpipes shall be provided with Siamese fire department connections on the outside of the structure, at the street level, which shall be conspicuously marked. There shall be at least one standard hose outlet at each floor.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35162, June 30, 1993; 61 FR 31432, June 20, 1996]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 51 FR 25318, July 11, 1986]
| Fire protection provided | Fire resistance | Maximum size | Total allowable quantities gals./sq. ft./floor area |
|---|---|---|---|
| Yes | 2 hrs | 500 sq. ft | 10 |
| No | 2 hrs | 500 sq. ft | 4 |
| Yes | 1 hr | 150 sq. ft | 5 |
| No | 1 hr | 150 sq. ft | 2 |
| Note: Fire protection system shall be sprinkler, water spray, carbon dioxide or other system approved by a nationally recognized testing laboratory for this purpose. |
The quantity of flammable liquids kept in the vicinity of spraying operations shall be the minimum required for operations and should ordinarily not exceed a supply for 1 day or one shift. Bulk storage of portable containers of flammable liquids shall be in a separate, constructed building detached from other important buildings or cut off in a standard manner.
This section applies to the handling, storage, and use of flammable liquids with a flashpoint at or below 199.4 °F (93 °C). This section does not apply to:
142, Standard for Steel Aboveground Tanks for Flammable and Combustible Liquids, 1968; No. 58, Standard for Steel Underground Tanks for Flammable and Combustible Liquids, Fifth Edition, December 1961; or No. 80, Standard for Steel Inside Tanks for Oil-Burner Fuel, September 1963.
12A, Specification for Oil Storage Tanks with Riveted Shells, Seventh Edition, September 1951, or No. 650, Welded Steel Tanks for Oil Storage, Third Edition, 1966.
12B, Specification for Bolted Production Tanks, Eleventh Edition, May 1958, and Supplement 1, March 1962; No. 12D, Specification for Large Welded Production Tanks, Seventh Edition, August 1957; or No. 12F, Specification for Small Welded Production Tanks, Fifth Edition, March 1961. Tanks built in accordance with these standards shall be used only as production tanks for storage of crude petroleum in oil-producing areas.
620. Recommended Rules for the Design and Construction of Large, Welded, Low-Pressure Storage Tanks, Third Edition, 1966.
This paragraph may be used for operating pressures not exceeding 1 p.s.i.g.
When tanks are not designed in accordance with the American Petroleum Institute, American Society of Mechanical Engineers, or the Underwriters' Laboratories, Inc.'s, standards, or if corrosion is anticipated beyond that provided for in the design formulas used, additional metal thickness or suitable protective coatings or linings shall be provided to compensate for the corrosion loss expected during the design life of the tank.
Exemption: Tanks of 3,000 bbls (barrels) (84 m(3)) capacity or less containing crude petroleum in crude-producing areas; and, outside aboveground atmospheric tanks under 1,000 gallons (3,785 L) capacity containing other than Category 1 flammable liquids may have open vents. ( See paragraph (i)(2)(vi)(B) of this section.)
| Square feet (m 2 ) | CFH (m 3 H) | Square feet (m 2 ) | CFH (m 3 H) | Square feet (m 2 ) | CFH (m 3 H) |
|---|---|---|---|---|---|
| 20 (1.84) | 21,100 (590.8) | 200 (18.4) | 211,000 (5,908) | 1,000 (90.2) | 524,000 (14,672) |
| 30 (2.76) | 31,600 (884.8) | 250 (23) | 239,000 (6,692) | 1,200 (110.4) | 557,000 (15,596) |
| 40 (3.68) | 42,100 (1,178.8) | 300 (27.6) | 265,000 (7,420) | 1,400 (128.8) | 587,000 (16,436) |
| 50 (4.6) | 52,700 (1,475.6) | 350 (32.2) | 288,000 (8,064) | 1,600 (147.2) | 614,000 (17,192) |
| 60 (5.52) | 63,200 (1,769.6) | 400 (36.8) | 312,000 (8,736) | 1,800 (165.6) | 639,000 (17,892) |
| 70 (6.44) | 73,700 (2,063.6) | 500 (46) | 354,000 (9,912) | 2,000 (180.4) | 662,000 (18,536) |
| 80 (7.36) | 84,200 (2,357.6) | 600 (55.2) | 392,000 (10,976) | 2,400 (220.8) | 704,000 (19,712) |
| 90 (8.28) | 94,800 (2,654.4) | 700 (64.4) | 428,000 (11,984) | 2,800 (257.6) | 742,000 (20,776) |
| 100 (9.2) | 105,000 (2,940) | 800 (73.6) | 462,000 (12,936) | and | |
| 120 (11.04) | 126,000 (3,528) | 900 (82.8) | 493,000 (13,804) | over | |
| 140 (12.88) | 147,000 (4,116) | 1,000 (90.2) | 524,000 (14,672) | ||
| 160 (14.72) | 168,000 (4,704) | ||||
| 180 (16.56) | 190,000 (5,320) | ||||
| 200 (18.4) | 211,000 (5,908) |
CFH
A
0.82
Where:
CFH
A
2
V
L
√
M
V
L
M
0.5 for drainage in accordance with paragraph (i)(2)(vii)(B) of this section for tanks over 200 square feet (18.4 m 2 ) of wetted area.
0.3 for approved water spray.
0.3 for approved insulation.
0.15 for approved water spray with approved insulation.
The area surrounding a tank or a group of tanks shall be provided with drainage as in paragraph (i)(2)(vii)(B) of this section, or shall be diked as provided in (i)(2)(vii)(C) of this section, to prevent accidental discharge of liquid from endangering adjoining property or reaching waterways.
Where protection of adjoining property or waterways is by means of a natural or manmade drainage system, such systems shall comply with the following:
Where protection of adjoining property or waterways is accomplished by retaining the liquid around the tank by means of a dike, the volume of the diked area shall comply with the following requirements:
Evacuation for underground storage tanks shall be made with due care to avoid undermining of foundations of existing structures. Underground tanks or tanks under buildings shall be so located with respect to existing building foundations and supports that the loads carried by the latter cannot be transmitted to the tank. The distance from any part of a tank storing Category 1 or 2 flammable liquids, or Category 3 flammable liquids with a flashpoint below 100 °F (37.8 °C), to the nearest wall of any basement or pit shall be not less than 1 foot (0.304 m), and to any property line that may be built upon, not less than 3 feet (0.912 m). The distance from any part of a tank storing Category 3 flammable liquids with a flashpoint at or above 100 °F (37.8 °C) or Category 4 flammable liquids to the nearest wall of any basement, pit or property line shall be not less than 1 foot (0.304 m).
Underground tanks shall be set on firm foundations and surrounded with at least 6 inches (15.24 cm) of noncorrosive, inert materials such as clean sand, earth, or gravel well tamped in place. The tank shall be placed in the hole with care since dropping or rolling the tank into the hole can break a weld, puncture or damage the tank, or scrape off the protective coating of coated tanks. Tanks shall be covered with a minimum of 2 feet (0.608 m) of earth, or shall be covered with not less than 1 foot (0.304 m) of earth, on top of which shall be placed a slab of reinforced concrete not less than 4 inches (10.16 cm) thick. When underground tanks are, or are likely to be, subject to traffic, they shall be protected against damage from vehicles passing over them by at least 3 feet (0.912 m) of earth cover, or 18 inches (45.72 cm) of well-tamped earth, plus 6 inches (15.24 cm) of reinforced concrete or 8 inches (20.32 cm) of asphaltic concrete. When asphaltic or reinforced concrete paving is used as part of the protection, it shall extend at least 1 foot (0.304 m) horizontally beyond the outline of the tank in all directions.
Corrosion protection for the tank and its piping shall be provided by one or more of the following methods:
Each tank shall be vented through piping adequate in size to prevent blow-back of vapor or liquid at the fill opening while the tank is being filled. Vent pipes shall be not less than 1 1/4 inch (3.175 cm) nominal inside diameter.
| Maximum flow GPM (L) | Pipe length 1 | ||
|---|---|---|---|
| 50 feet (15.2 m) | 100 feet (30.4 m) | 200 feet (60.8 m) | |
| Inches (cm) | Inches (cm) | Inches (cm) | |
| 100 (378.5) | 1 1 ⁄ 4 (3.175) | 1 1 ⁄ 4 (3.175) | 1 1 ⁄ 4 (3.175) |
| 200 (757) | 1 1 ⁄ 4 (3.175) | 1 1 ⁄ 4 (3.175) | 1 1 ⁄ 4 (3.175) |
| 300 (1,135.5) | 1 1 ⁄ 4 (3.175) | 1 1 ⁄ 4 (3.175) | 1 1 ⁄ 2 (3.81) |
| 400 (1,514) | 1 1 ⁄ 4 (3.175) | 1 1 ⁄ 2 (3.81) | 2 (5.08) |
| 500 (1,892.5) | 1 1 ⁄ 2 (3.81) | 1 1 ⁄ 2 (3.81) | 2 (5.08) |
| 600 (2,271) | 1 1 ⁄ 2 (3.81) | 2 (5.08) | 2 (5.08) |
| 700 (2,649.5) | 2 (5.08) | 2 (5.08) | 2 (5.08) |
| 800 (3,028) | 2 (5.08) | 2 (5.08) | 3 (7.62) |
| 900 (3,406.5) | 2 (5.08) | 2 (5.08) | 3 (7.62) |
| 1,000 (3,785) | 2 (5.08) | 2 (5.08) | 3 (7.62) |
| 1 Vent lines of 50 ft. (15.2 m), 100 ft. (30.4 m), and 200 ft. (60.8 m) of pipe plus 7 ells. |
Tanks shall not be permitted inside of buildings except as provided in paragraphs (e), (g), (h), or (i) of this section.
Vents for tanks inside of buildings shall be as provided in paragraphs (i)(2) (iv), (v), (vi)(B), and (3)(iv) of this section, except that emergency venting by the use of weak roof seams on tanks shall not be permitted. Vents shall discharge vapors outside the buildings.
Vent piping shall be constructed in accordance with paragraph (c) of this section.
Tank supports shall be installed on firm foundations. Tank supports shall be of concrete, masonry, or protected steel. Single wood timber supports (not cribbing) laid horizontally may be used for outside aboveground tanks if not more than 12 inches (30.48 cm) high at their lowest point.
Steel supports or exposed piling shall be protected by materials having a fire resistance rating of not less than 2 hours, except that steel saddles need not be protected if less than 12 inches (30.48 cm) high at their lowest point. Water spray protection or its equivalent may be used in lieu of fire-resistive materials to protect supports.
The design of the supporting structure for tanks such as spheres shall receive special engineering consideration.
Every tank shall be so supported as to prevent the excessive concentration of loads on the supporting portion of the shell.
Tanks shall rest on the ground or on foundations made of concrete, masonry, piling, or steel. Tank foundations shall be designed to minimize the possibility of uneven settling of the tank and to minimize corrosion in any part of the tank resting on the foundation.
Where a tank is located in an area that may be subjected to flooding, the applicable precautions outlined in this subdivision shall be observed.
The Assistant Secretary or his designated representative shall make periodic inspections of all plants where the storage of flammable liquids is such as to require compliance with the foregoing requirements, in order to assure the following:
In areas subject to earthquakes, the tank supports and connections shall be designed to resist damage as a result of such shocks.
In locations where flammable vapors may be present, precautions shall be taken to prevent ignition by eliminating or controlling sources of ignition. Sources of ignition may include open flames, lightning, smoking, cutting and welding, hot surfaces, frictional heat, sparks (static, electrical, and mechanical), spontaneous ignition, chemical and physical-chemical reactions, and radiant heat.
All tanks, whether shop built or field erected, shall be strength tested before they are placed in service in accordance with the applicable paragraphs of the code under which they were built. The American Society of Mechanical Engineers (ASME) code stamp, American Petroleum Institute (API) monogram, or the label of the Underwriters' Laboratories, Inc., on a tank shall be evidence of compliance with this strength test. Tanks not marked in accordance with the above codes shall be strength tested before they are placed in service in accordance with good engineering principles and reference shall be made to the sections on testing in the codes listed in paragraphs (i)(1) (iii)(A), (iv)(B), or (v)(B) of this section.
When the vertical length of the fill and vent pipes is such that when filled with liquid the static head imposed upon the bottom of the tank exceeds 10 pounds per square inch (68.94 kPa), the tank and related piping shall be tested hydrostatically to a pressure equal to the static head thus imposed.
In addition to the strength test called for in paragraphs (i)(7) (i) and (ii) of this section, all tanks and connections shall be tested for tightness. Except for underground tanks, this tightness test shall be made at operating pressure with air, inert gas, or water prior to placing the tank in service. In the case of field-erected tanks the strength test may be considered to be the test for tank tightness. Underground tanks and piping, before being covered, enclosed, or placed in use, shall be tested for tightness hydrostatically, or with air pressure at not less than 3 pounds per square inch (20.68 kPa) and not more than 5 pounds per square inch (34.47 kPa).
All leaks or deformations shall be corrected in an acceptable manner before the tank is placed in service. Mechanical caulking is not permitted for correcting leaks in welded tanks except pinhole leaks in the roof.
Tanks to be operated at pressures below their design pressure may be tested by the applicable provisions of paragraphs (i)(7) (i) or (ii) of this section, based upon the pressure developed under full emergency venting of the tank.
The design (including selection of materials) fabrication, assembly, test, and inspection of piping systems containing flammable liquids shall be suitable for the expected working pressures and structural stresses. Conformity with the applicable provisions of Pressure Piping, ANSI B31 series and the provisions of this paragraph, shall be considered prima facie evidence of compliance with the foregoing provisions.
This paragraph does not apply to any of the following:
As used in this paragraph, piping systems consist of pipe, tubing, flanges, bolting, gaskets, valves, fittings, the pressure containing parts of other components such as expansion joints and strainers, and devices which serve such purposes as mixing, separating, snubbing, distributing, metering, or controlling flow.
Materials for piping, valves, or fittings shall be steel, nodular iron, or malleable iron, except as provided in paragraphs (j)(2) (ii), (iii) and (iv) of this section.
Materials other than steel, nodular iron, or malleable iron may be used underground, or if required by the properties of the flammable liquid handled. Material other than steel, nodular iron, or malleable iron shall be designed to specifications embodying principles recognized as good engineering practices for the material used.
Piping, valves, and fittings may have combustible or noncombustible linings.
When low-melting point materials such as aluminum and brass or materials that soften on fire exposure such as plastics, or non-ductile materials such as cast iron, are necessary, special consideration shall be given to their behavior on fire exposure. If such materials are used in above ground piping systems or inside buildings, they shall be suitably protected against fire exposure or so located that any spill resulting from the failure of these materials could not unduly expose persons, important buildings or structures or can be readily controlled by remote valves.
Joints shall be made liquid tight. Welded or screwed joints or approved connectors shall be used. Threaded joints and connections shall be made up tight with a suitable lubricant or piping compound. Pipe joints dependent upon the friction characteristics of combustible materials for mechanical continuity of piping shall not be used inside buildings. They may be used outside of buildings above or below ground. If used above ground, the piping shall either be secured to prevent disengagement at the fitting or the piping system shall be so designed that any spill resulting from such disengagement could not unduly expose persons, important buildings or structures, and could be readily controlled by remote valves.
Piping systems shall be substantially supported and protected against physical damage and excessive stresses arising from settlement, vibration, expansion, or contraction.
All piping for flammable liquids, both aboveground and underground, where subject to external corrosion, shall be painted or otherwise protected.
Piping systems shall contain a sufficient number of valves to operate the system properly and to protect the plant. Piping systems in connection with pumps shall contain a sufficient number of valves to control properly the flow of liquid in normal operation and in the event of physical damage. Each connection to pipelines, by which equipments such as tankcars or tank vehicles discharge liquids by means of pumps into storage tanks, shall be provided with a check valve for automatic protection against backflow if the piping arrangement is such that backflow from the system is possible.
All piping before being covered, enclosed, or placed in use shall be hydrostatically tested to 150 percent of the maximum anticipated pressure of the system, or pneumatically tested to 110 percent of the maximum anticipated pressure of the system, but not less than 5 pounds per square inch gage at the highest point of the system. This test shall be maintained for a sufficient time to complete visual inspection of all joints and connections, but for at least 10 minutes.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 51 FR 25318, July 11, 1986; 58 FR 35162, June 30, 1993; 63 FR 33469, June 18, 1998; 77 FR 17891, Mar. 26, 2012]
As used in this section, Containers —All vessels, such as tanks, cylinders, or drums, used for transportation or storing liquefied petroleum gases.
Welding is prohibited on containers.
Storage of LPG within buildings is prohibited.
| Quantity of LP-Gas stored | Distance (feet) |
|---|---|
| 500 lbs. or less | 0 |
| 501 to 6,000 lbs | 10 |
| 6,001 to 10,000 lbs | 20 |
| Over 10,000 lbs | 25 |
Storage locations shall be provided with at least one approved portable fire extinguisher having a rating of not less than 20-B:C.
This paragraph applies specifically to systems utilizing storage containers other than those constructed in accordance with DOT specifications. Paragraph (b) of this section applies to this paragraph unless otherwise noted in paragraph (b) of this section.
Storage containers shall be designed and classified in accordance with Table F-31.
| Container type | For gases with vapor press. Not to exceed lb. per sq. in. gage at 100 °F. (37.8 °C.) | Minimum design pressure of container, lb. per sq. in. gage | |
|---|---|---|---|
| 1949 and earlier editions of ASME Code (Par. U-68, U-69) | 1949 edition of ASME Code (Par. U-200, U-201); 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of ASME Code; All editions of API-ASME Code 3 | ||
| 1 80 | 1 80 | 1 80 | 1 100 |
| 100 | 100 | 100 | 125 |
| 125 | 125 | 125 | 156 |
| 150 | 150 | 150 | 187 |
| 175 | 175 | 175 | 219 |
| 2 200 | 215 | 200 | 250 |
| 1 New storage containers of the 80 type have not been authorized since Dec. 31, 1947. | |||
| 2 Container type may be increased by increments of 25. The minimum design pressure of containers shall be 100% of the container type designation when constructed under 1949 or earlier editions of the ASME Code (Par. U-68 and U-69). The minimum design pressure of containers shall be 125% of the container type designation when constructed under: (1) the 1949 ASME Code (Par. U-200 and U-201), (2) 1950, 1952, 1956, 1959, 1962, 1965, and 1968 (Division 1) editions of the ASME Code, and (3) all editions of the API-ASME Code. | |||
| 3 Construction of containers under the API-ASME Code is not authorized after July 1, 1961. |
When damage to LP-Gas systems from vehicular traffic is a possibility, precautions against such damage shall be taken.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35170, June 30, 1993]
| Heating appliances | Minimum clearance, (inches) | ||
|---|---|---|---|
| Sides | Rear | Chimney connector | |
| Room heater, circulating type | 12 | 12 | 18 |
| Room heater, radiant type | 36 | 36 | 18 |
Heaters, when in use, shall be set horizontally level, unless otherwise permitted by the manufacturer's markings.
Solid fuel salamanders are prohibited in buildings and on scaffolds.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 77 FR 17894, Mar. 26, 2012]
Signs and symbols required by this subpart shall be visible at all times when work is being performed, and shall be removed or covered promptly when the hazards no longer exist.
Exit signs, when required, shall be lettered in legible red letters, not less than 6 inches high, on a white field and the principal stroke of the letters shall be at least three-fourths inch in width.
Safety instruction signs, when used, shall be white with green upper panel with white letters to convey the principal message. Any additional wording on the sign shall be black letters on the white background.
Directional signs, other than automotive traffic signs specified in paragraph (g) of this section, shall be white with a black panel and a white directional symbol. Any additional wording on the sign shall be black letters on the white background.
ANSI Z35.1-1968, ANSI Z535.2-2011, ANSI Z35.2-1968, and ANSI Z535.5-2011, incorporated by reference in § 1926.6, contain rules in addition to those specifically prescribed in this subpart. The employer shall comply with ANSI Z35.1-1968 or ANSI Z535.2-2011, and ANSI Z35.2-1968 or Z535.5-2011, with respect to such additional rules.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35173, June 30, 1993; 67 FR 57736, Sept. 12, 2002; 69 FR 18803, Apr. 9, 2004; 78 FR 35567, June 13, 2013; 78 FR 66642, Nov. 6, 2013; 84 FR 21577, May 14, 2019]
Signaling by flaggers and the use of flaggers, including warning garments worn by flaggers, shall conform to Part 6 of the MUTCD (incorporated by reference, see § 1926.6).
Regulations for crane and hoist signaling will be found in applicable American National Standards Institute standards.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 67 FR 57736, Sept. 12, 2002; 78 FR 35567, June 13, 2013; 84 FR 21577, May 14, 2019]
Storage areas shall be kept free from accumulation of materials that constitute hazards from tripping, fire, explosion, or pest harborage. Vegetation control will be exercised when necessary.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 49 FR 18295, Apr. 30, 1984; 54 FR 24334, June 7, 1989; 58 FR 35173, June 30, 1993; 59 FR 40729, Aug. 9, 1994; 61 FR 5510, Feb. 13, 1996; 84 FR 21577, May 14, 2019]
This section applies to slings used in conjunction with other material handling equipment for the movement of material by hoisting, in employments covered by this part. The types of slings covered are those made from alloy steel chain, wire rope, metal mesh, natural or synthetic fiber rope (conventional three strand construction), and synthetic web (nylon, polyester, and polypropylene).
Each day before being used, the sling and all fastenings and attachments shall be inspected for damage or defects by a competent person designated by the employer. Additional inspections shall be performed during sling use, where service conditions warrant. Damaged or defective slings shall be immediately removed from service.
Fiber core wire rope slings of all grades shall be permanently removed from service if they are exposed to temperatures in excess of 200 °F (93.33 °C). When nonfiber core wire rope slings of any grade are used at temperatures above 400 °F (204.44 °C) or below minus 60 °F (15.55 °C), recommendations of the sling manufacturer regarding use at that temperature shall be followed.
Natural and synthetic fiber rope slings, except for wet frozen slings, may be used in a temperature range from minus 20 °F (−28.88 °C) to plus 180 °F (82.2 °C) without decreasing the working load limit. For operations outside this temperature range and for wet frozen slings, the sling manufacturer's recommendations shall be followed.
Spliced fiber rope slings shall not be used unless they have been spliced in accordance with the following minimum requirements and in accordance with any additional recommendations of the manufacturer:
Fiber rope slings shall not be used if end attachments in contact with the rope have sharp edges or projections.
Natural and synthetic fiber rope slings shall be immediately removed from service if any of the following conditions are present:
Synthetic webbing shall be of uniform thickness and width and selvage edges shall not be split from the webbing's width.
Fittings shall be:
When synthetic web slings are used, the following precautions shall be taken:
Synthetic web slings of polyester and nylon shall not be used at temperatures in excess of 180 °F (82.2 °C). Polypropylene web slings shall not be used at temperatures in excess of 200 °F (93.33 °C).
Synthetic web slings shall be immediately removed from service if any of the following conditions are present:
| Chain size (inches) | Maximum allowable wear (inch) |
|---|---|
| 1 ⁄ 4 | 3 ⁄ 64 |
| 3 ⁄ 8 | 5 ⁄ 64 |
| 1 ⁄ 2 | 7 ⁄ 64 |
| 5 ⁄ 8 | 9 ⁄ 64 |
| 3 ⁄ 4 | 5 ⁄ 32 |
| 7 ⁄ 8 | 11 ⁄ 64 |
| 1 | 3 ⁄ 16 |
| 1 1 ⁄ 8 | 7 ⁄ 32 |
| 1 1 ⁄ 4 | 1 ⁄ 4 |
| 1 3 ⁄ 8 | 9 ⁄ 32 |
| 1 1 ⁄ 2 | 5 ⁄ 16 |
| 1 3 ⁄ 4 | 11 ⁄ 32 |
| Improved plow steel, rope diameter (inches) | Number of clips | Minimum spacing (inches) | |
|---|---|---|---|
| Drop forged | Other material | ||
| 1 ⁄ 2 | 3 | 4 | 3 |
| 5 ⁄ 8 | 3 | 4 | 3 3 ⁄ 4 |
| 3 ⁄ 4 | 4 | 5 | 4 1 ⁄ 2 |
| 7 ⁄ 8 | 4 | 5 | 5 1 ⁄ 4 |
| 1 | 5 | 6 | 6 |
| 1 1 ⁄ 8 | 6 | 6 | 6 3 ⁄ 4 |
| 1 1 ⁄ 4 | 6 | 7 | 7 1 ⁄ 2 |
| 1 3 ⁄ 8 | 7 | 7 | 8 1 ⁄ 4 |
| 1 1 ⁄ 2 | 7 | 8 | 9 |
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35173, June 30, 1993; 76 FR 33611, June 8, 2011; 77 FR 23118, Apr. 18, 2012]
All hand and power tools and similar equipment, whether furnished by the employer or the employee, shall be maintained in a safe condition.
One or more methods of machine guarding shall be provided to protect the operator and other employees in the machine area from hazards such as those created by point of operation, ingoing nip points, rotating parts, flying chips and sparks. Examples of guarding methods are—barrier guards, two-hand tripping devices, electronic safety devices, etc.
When the periphery of the blades of a fan is less than 7 feet (2.128 m) above the floor or working level, the blades shall be guarded. The guard shall have openings no larger than 1/2 inch (1.27 cm).
Machines designed for a fixed location shall be securely anchored to prevent walking or moving.
Safety guards of the types described in paragraphs (b) (8) and (9) of this section, where the operator stands in front of the opening, shall be constructed so that the peripheral protecting member can be adjusted to the constantly decreasing diameter of the wheel. The maximum angular exposure above the horizontal plane of the wheel spindle as specified in paragraphs (b) (8) and (9) of this section shall never be exceeded, and the distance between the wheel periphery and the adjustable tongue or the end of the peripheral member at the top shall never exceed 1/4 inch (0.635 cm). (See Figures I-1 through I-6.)
Correct
Showing adjustable tongue giving required angle protection for all sizes of wheel used.
Correct
Showing movable guard with opening small enough to give required protection for the smallest size wheel used.
Showing movable guard with size of opening correct for full size wheel but too large for smaller wheel.
The angular exposure of the grinding wheel periphery and sides for safety guards used on machines known as bench and floor stands should not exceed 90° or one-fourth of the periphery. This exposure shall begin at a point not more than 65° above the horizontal plane of the wheel spindle. (See Figures I-7 and I-8 and paragraph (b)(7) of this section.)
The maximum angular exposure of the grinding wheel periphery and sides for safety guards used on cylindrical grinding machines shall not exceed 180°. This exposure shall begin at a point not more than 65° above the horizontal plane of the wheel spindle. (See Figures I-11 and I-12 and paragraph (b)(7) of this section.)
Employees using hand and power tools and exposed to the hazard of falling, flying, abrasive, and splashing objects, or exposed to harmful dusts, fumes, mists, vapors, or gases shall be provided with the particular personal protective equipment necessary to protect them from the hazard. All personal protective equipment shall meet the requirements and be maintained according to subparts D and E of this part.
This paragraph does not apply to concrete vibrators, concrete breakers, powered tampers, jack hammers, rock drills, and similar hand operated power tools.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35175, June 30, 1993; 61 FR 9250, Mar. 7, 1996]
The blast cleaning nozzles shall be equipped with an operating valve which must be held open manually. A support shall be provided on which the nozzle may be mounted when it is not in use.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35175, June 30, 1993]
All grinding machines shall be supplied with sufficient power to maintain the spindle speed at safe levels under all conditions of normal operation.
The safety guard shall cover the spindle end, nut, and flange projections. The safety guard shall be mounted so as to maintain proper alignment with the wheel, and the strength of the fastenings shall exceed the strength of the guard, except:
All abrasive wheels and tools used by employees shall meet other applicable requirements of American National Standards Institute, B7.1-1970, Safety Code for the Use, Care and Protection of Abrasive Wheels.
On offhand grinding machines, work rests shall be used to support the work. They shall be of rigid construction and designed to be adjustable to compensate for wheel wear. Work rests shall be kept adjusted closely to the wheel with a maximum opening of 1/8 inch (0.3175 cm) to prevent the work from being jammed between the wheel and the rest, which may cause wheel breakage. The work rest shall be securely clamped after each adjustment. The adjustment shall not be made with the wheel in motion.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35175, June 30, 1993]
All fixed power driven woodworking tools shall be provided with a disconnect switch that can either be locked or tagged in the off position.
The operating speed shall be etched or otherwise permanently marked on all circular saws over 20 inches in diameter or operating at over 10,000 peripheral feet per minute. Any saw so marked shall not be operated at a speed other than that marked on the blade. When a marked saw is retensioned for a different speed, the marking shall be corrected to show the new speed.
Automatic feeding devices shall be installed on machines whenever the nature of the work will permit. Feeder attachments shall have the feed rolls or other moving parts covered or guarded so as to protect the operator from hazardous points.
All portable, power-driven circular saws shall be equipped with guards above and below the base plate or shoe. The upper guard shall cover the saw to the depth of the teeth, except for the minimum arc required to permit the base to be tilted for bevel cuts. The lower guard shall cover the saw to the depth of the teeth, except for the minimum arc required to allow proper retraction and contact with the work. When the tool is withdrawn from the work, the lower guard shall automatically and instantly return to the covering position.
All personal protective equipment provided for use shall conform to subpart E of this part.
All woodworking tools and machinery shall meet other applicable requirements of American National Standards Institute, 01.1-1961, Safety Code for Woodworking Machinery.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35175, June 30, 1993; 61 FR 9251, Mar. 7, 1996]
When it is necessary to provide a firm foundation, the base of the jack shall be blocked or cribbed. Where there is a possibility of slippage of the metal cap of the jack, a wood block shall be placed between the cap and the load.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 55 FR 42328, Oct. 18, 1990; 58 FR 35176, June 30, 1993]
This section applies to compressed air receivers, and other equipment used in providing and utilizing compressed air for performing operations such as cleaning, drilling, hoisting, and chipping. On the other hand, however, this section does not deal with the special problems created by using compressed air to convey materials nor the problems created when men work in compressed air as in tunnels and caissons. This section is not intended to apply to compressed air machinery and equipment used on transportation vehicles such as steam railroad cars, electric railway cars, and automotive equipment.
Air receivers shall be so installed that all drains, handholes, and manholes therein are easily accessible. Under no circumstances shall an air receiver be buried underground or located in an inaccessible place.
A drain pipe and valve shall be installed at the lowest point of every air receiver to provide for the removal of accumulated oil and water. Adequate automatic traps may be installed in addition to drain valves. The drain valve on the air receiver shall be opened and the receiver completely drained frequently and at such intervals as to prevent the accumulation of excessive amounts of liquid in the receiver.
[58 FR 35176, June 30, 1993]
Flywheels located so that any part is 7 feet (2.128 m) or less above floor or platform shall be guarded in accordance with the requirements of this subparagraph:
Cranks and connecting rods, when exposed to contact, shall be guarded in accordance with paragraphs (m) and (n) of this section, or by a guardrail as described in paragraph (o)(5) of this section.
Tail rods or extension piston rods shall be guarded in accordance with paragraphs (m) and (o) of this section, or by a guardrail on sides and end, with a clearance of not less than 15 (38.1 cm) nor more than 20 inches (50.8 cm) when rod is fully extended.
Vertical and inclined shafting 7 feet (2.128 m) or less from floor or working platform, excepting maintenance runways, shall be enclosed with a stationary casing in accordance with requirements of paragraphs (m) and (o) of this section.
All mechanical power transmission apparatus located in basements, towers, and rooms used exclusively for power transmission equipment shall be guarded in accordance with this section, except that the requirements for safeguarding belts, pulleys, and shafting need not be complied with when the following requirements are met:
Pulleys, any parts of which are 7 feet (2.128 m) or less from the floor or working platform, shall be guarded in accordance with the standards specified in paragraphs (m) and (o) of this section. Pulleys serving as balance wheels ( e.g., punch presses) on which the point of contact between belt and pulley is more than 6 ft. 6 in. (1.976 m) from the floor or platform may be guarded with a disk covering the spokes.
Pulleys with cracks, or pieces broken out of rims, shall not be used.
Pulleys intended to operate at rim speed in excess of manufacturers normal recommendations shall be specially designed and carefully balanced for the speed at which they are to operate.
Vertical belts running over a lower pulley more than 7 feet (2.128 m) above floor or platform shall be guarded at the bottom in the same manner as horizontal overhead belts, if conditions are as stated in paragraphs (e)(2)(ii) ( a ) and ( c ) of this section.
Gears shall be guarded in accordance with one of the following methods:
Paragraph (f)(1) of this section does not apply to hand-operated gears used only to adjust machine parts and which do not continue to move after hand power is removed. However, the guarding of these gears is highly recommended.
All sprocket wheels and chains shall be enclosed unless they are more than 7 feet (2.128 m) above the floor or platform. Where the drive extends over other machine or working areas, protection against falling shall be provided. This subparagraph does not apply to manually operated sprockets.
When frequent oiling must be done, openings with hinged or sliding self-closing covers shall be provided. All points not readily accessible shall have oil feed tubes if lubricant is to be added while machinery is in motion.
The driving point of all friction drives when exposed to contact shall be guarded, all arm or spoke friction drives and all web friction drives with holes in the web shall be entirely enclosed, and all projecting belts on friction drives where exposed to contact shall be guarded.
All revolving collars, including split collars, shall be cylindrical, and screws or bolts used in collars shall not project beyond the largest periphery of the collar.
Shaft couplings shall be so constructed as to present no hazard from bolts, nuts, setscrews, or revolving surfaces. Bolts, nuts, and setscrews will, however, be permitted where they are covered with safety sleeves or where they are used parallel with the shafting and are countersunk or else do not extend beyond the flange of the coupling.
All drip cups and pans shall be securely fastened.
Clutches, cutoff couplings, or clutch pulleys having projecting parts, where such clutches are located 7 feet (2.128 m) or less above the floor or working platform, shall be enclosed by a stationary guard constructed in accordance with this section. A “U” type guard is permissible.
In engine rooms a guardrail, preferably with toeboard, may be used instead of the guard required by paragraph (k)(1) of this section, provided such a room is occupied only by engine room attendants.
The use of belt poles as substitutes for mechanical shifters is not recommended.
Where loose pulleys or idlers are not practicable, belt perches in form of brackets, rollers, etc., shall be used to keep idle belts away from the shafts.
Belts which of necessity must be shifted by hand and belts within 7 feet (2.128 m) of the floor or working platform which are not guarded in accordance with this section shall not be fastened with metal in any case, nor with any other fastening which by construction or wear will constitute an accident hazard.
The materials and dimensions specified in this paragraph shall apply to all guards, except horizontal overhead belts, rope, cable, or chain guards more than 7 feet (2.128 m) above floor, or platform.
Overhead-rope and chain-drive guard construction shall conform to the rules for overhead-belt guard.
All power-transmission equipment shall be inspected at intervals not exceeding 60 days and be kept in good working condition at all times.
Bearings shall be kept in alignment and properly adjusted.
Hangers shall be inspected to make certain that all supporting bolts and screws are tight and that supports of hanger boxes are adjusted properly.
The regular oilers shall wear tight-fitting clothing. Machinery shall be oiled when not in motion, wherever possible.
[58 FR 35176, June 30, 1993, as amended at 69 FR 31882, June 8, 2004]
The employer shall thoroughly instruct employees in the safe use of fuel gas, as follows:
Oxygen and fuel gas pressure regulators, including their related gauges, shall be in proper working order while in use.
Oxygen cylinders and fittings shall be kept away from oil or grease. Cylinders, cylinder caps and valves, couplings, regulators, hose, and apparatus shall be kept free from oil or greasy substances and shall not be handled with oily hands or gloves. Oxygen shall not be directed at oily surfaces, greasy clothes, or within a fuel oil or other storage tank or vessel.
For additional details not covered in this subpart, applicable technical portions of American National Standards Institute, Z49.1-1967, Safety in Welding and Cutting, shall apply.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 55 FR 42328, Oct. 18, 1990; 58 FR 35179, June 30, 1993]
Employers shall instruct employees in the safe means of arc welding and cutting as follows:
Whenever practicable, all arc welding and cutting operations shall be shielded by noncombustible or flameproof screens which will protect employees and other persons working in the vicinity from the direct rays of the arc.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 51 FR 25318, July 11, 1986]
For purposes of this section, mechanical ventilation shall meet the following requirements:
Where a welder must enter a confined space through a manhole or other small opening, means shall be provided for quickly removing him in case of emergency. When safety belts and lifelines are used for this purpose they shall be so attached to the welder's body that his body cannot be jammed in a small exit opening. An attendant with a pre-planned rescue procedure shall be stationed outside to observe the welder at all times and be capable of putting rescue operations into effect.
Because of its high toxicity, work involving beryllium shall be done with both local exhaust ventilation and air line respirators.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 55 FR 42328, Oct. 18, 1990; 58 FR 35179, June 30, 1993]
This subpart addresses electrical safety requirements that are necessary for the practical safeguarding of employees involved in construction work and is divided into four major divisions and applicable definitions as follows:
Installation safety requirements are contained in §§ 1926.402 through 1926.408. Included in this category are electric equipment and installations used to provide electric power and light on jobsites.
Safety-related work practices are contained in §§ 1926.416 and 1926.417. In addition to covering the hazards arising from the use of electricity at jobsites, these regulations also cover the hazards arising from the accidental contact, direct or indirect, by employees with all energized lines, above or below ground, passing through or near the jobsite.
Safety-related maintenance and environmental considerations are contained in §§ 1926.431 and 1926.432.
Safety requirements for special equipment are contained in § 1926.441.
Definitions applicable to this subpart are contained in § 1926.449.
Sections 1926.402 through 1926.408 contain installation safety requirements for electrical equipment and installations used to provide electric power and light at the jobsite. These sections apply to installations, both temporary and permanent, used on the jobsite; but these sections do not apply to existing permanent installations that were in place before the construction activity commenced.
Sections 1926.402 through 1926.408 do not cover installations used for the generation, transmission, and distribution of electric energy, including related communication, metering, control, and transformation installations. (However, these regulations do cover portable and vehicle-mounted generators used to provide power for equipment used at the jobsite.) See subpart V of this part for the construction of power distribution and transmission lines.
All electrical conductors and equipment shall be approved.
The employer shall ensure that electrical equipment is free from recognized hazards that are likely to cause death or serious physical harm to employees. Safety of equipment shall be determined on the basis of the following considerations:
Listed, labeled, or certified equipment shall be installed and used in accordance with instructions included in the listing, labeling, or certification.
Equipment intended to break current shall have an interrupting rating at system voltage sufficient for the current that must be interrupted.
Electric equipment shall be firmly secured to the surface on which it is mounted. Wooden plugs driven into holes in masonry, concrete, plaster, or similar materials shall not be used.
Electrical equipment which depends upon the natural circulation of air and convection principles for cooling of exposed surfaces shall be installed so that room air flow over such surfaces is not prevented by walls or by adjacent installed equipment. For equipment designed for floor mounting, clearance between top surfaces and adjacent surfaces shall be provided to dissipate rising warm air. Electrical equipment provided with ventilating openings shall be installed so that walls or other obstructions do not prevent the free circulation of air through the equipment.
Conductors shall be spliced or joined with splicing devices designed for the use or by brazing, welding, or soldering with a fusible metal or alloy. Soldered splices shall first be so spliced or joined as to be mechanically and electrically secure without solder and then soldered. All splices and joints and the free ends of conductors shall be covered with an insulation equivalent to that of the conductors or with an insulating device designed for the purpose.
Parts of electric equipment which in ordinary operation produce arcs, sparks, flames, or molten metal shall be enclosed or separated and isolated from all combustible material.
Electrical equipment shall not be used unless the manufacturer's name, trademark, or other descriptive marking by which the organization responsible for the product may be identified is placed on the equipment and unless other markings are provided giving voltage, current, wattage, or other ratings as necessary. The marking shall be of sufficient durability to withstand the environment involved.
Sufficient access and working space shall be provided and maintained about all electric equipment to permit ready and safe operation and maintenance of such equipment.
Except as required or permitted elsewhere in this subpart, the dimension of the working space in the direction of access to live parts operating at 600 volts or less and likely to require examination, adjustment, servicing, or maintenance while alive shall not be less than indicated in Table K-1. In addition to the dimensions shown in Table K-1, workspace shall not be less than 30 inches (762 mm) wide in front of the electric equipment. Distances shall be measured from the live parts if they are exposed, or from the enclosure front or opening if the live parts are enclosed. Walls constructed of concrete, brick, or tile are considered to be grounded. Working space is not required in back of assemblies such as dead-front switchboards or motor control centers where there are no renewable or adjustable parts such as fuses or switches on the back and where all connections are accessible from locations other than the back.
| Nominal voltage to ground | Minimum clear distance for conditions 1 | ||
|---|---|---|---|
| (a) | (b) | (c) | |
| Feet 2 | Feet 2 | Feet 2 | |
| 0-150 | 3 | 3 | 3 |
| 151-600 | 3 | 3 1 ⁄ 2 | 4 |
| 1 Conditions (a), (b), and (c) are as follows: (a) Exposed live parts on one side and no live or grounded parts on the other side of the working space, or exposed live parts on both sides effectively guarded by insulating material. Insulated wire or insulated busbars operating at not over 300 volts are not considered live parts. (b) Exposed live parts on one side and grounded parts on the other side. (c) Exposed live parts on both sides of the workspace [not guarded as provided in Condition (a)] with the operator between. | |||
| 2 Note: For International System of Units (SI): one foot = 0.3048m. |
Working space required by this subpart shall not be used for storage. When normally enclosed live parts are exposed for inspection or servicing, the working space, if in a passageway or general open space, shall be guarded.
At least one entrance shall be provided to give access to the working space about electric equipment.
Where there are live parts normally exposed on the front of switchboards or motor control centers, the working space in front of such equipment shall not be less than 3 feet (914 mm).
The minimum headroom of working spaces about service equipment, switchboards, panelboards, or motor control centers shall be 6 feet 3 inches (1.91 m).
Conductors and equipment used on circuits exceeding 600 volts, nominal, shall comply with all applicable provisions of paragraphs (a) through (g) of this section and with the following provisions which supplement or modify those requirements. The provisions of paragraphs (j)(2), (j)(3), and (j)(4) of this section do not apply to equipment on the supply side of the service conductors.
Electrical installations in a vault, room, closet or in an area surrounded by a wall, screen, or fence, access to which is controlled by lock and key or other equivalent means, are considered to be accessible to qualified persons only. A wall, screen, or fence less than 8 feet (2.44 m) in height is not considered adequate to prevent access unless it has other features that provide a degree of isolation equivalent to an 8-foot (2.44-m) fence. The entrances to all buildings, rooms or enclosures containing exposed live parts or exposed conductors operating at over 600 volts, nominal, shall be kept locked or shall be under the observation of a qualified person at all times.
Electrical installations having exposed live parts shall be accessible to qualified persons only and shall comply with the applicable provisions of paragraph (j)(3) of this section.
Electrical installations that are open to unqualified persons shall be made with metal-enclosed equipment or shall be enclosed in a vault or in an area, access to which is controlled by a lock. Metal-enclosed switchgear, unit substations, transformers, pull boxes, connection boxes, and other similar associated equipment shall be marked with appropriate caution signs. If equipment is exposed to physical damage from vehicular traffic, guards shall be provided to prevent such damage. Ventilating or similar openings in metal-enclosed equipment shall be designed so that foreign objects inserted through these openings will be deflected from energized parts.
Sufficient space shall be provided and maintained about electric equipment to permit ready and safe operation and maintenance of such equipment. Where energized parts are exposed, the minimum clear workspace shall not be less than 6 feet 6 inches (1.98 m) high (measured vertically from the floor or platform), or less than 3 feet (914 mm) wide (measured parallel to the equipment). The depth shall be as required in Table K-2. The workspace shall be adequate to permit at least a 90-degree opening of doors or hinged panels.
The minimum clear working space in front of electric equipment such as switchboards, control panels, switches, circuit breakers, motor controllers, relays, and similar equipment shall not be less than specified in Table K-2 unless otherwise specified in this subpart. Distances shall be measured from the live parts if they are exposed, or from the enclosure front or opening if the live parts are enclosed. However, working space is not required in back of equipment such as deadfront switchboards or control assemblies where there are no renewable or adjustable parts (such as fuses or switches) on the back and where all connections are accessible from locations other than the back. Where rear access is required to work on de-energized parts on the back of enclosed equipment, a minimum working space of 30 inches (762 mm) horizontally shall be provided.
| Nominal voltage to ground | Conditions 1 | ||
|---|---|---|---|
| (a) | (b) | (c) | |
| Feet 2 | Feet 2 | Feet 2 | |
| 601 to 2,500 | 3 | 4 | 5 |
| 2,501 to 9,000 | 4 | 5 | 6 |
| 9,001 to 25,000 | 5 | 6 | 9 |
| 25,001 to 75 kV | 6 | 8 | 10 |
| Above 75kV | 8 | 10 | 12 |
| 1 Conditions (a), (b), and (c) are as follows: (a) Exposed live parts on one side and no live or grounded parts on the other side of the working space, or exposed live parts on both sides effectively guarded by insulating materials. Insulated wire or insulated busbars operating at not over 300 volts are not considered live parts. (b) Exposed live parts on one side and grounded parts on the other side. Walls constructed of concrete, brick, or tile are considered to be grounded surfaces. (c) Exposed live parts on both sides of the workspace [not guarded as provided in Condition (a)] with the operator between. | |||
| 2 Note: For SI units: one foot = 0.3048 m. |
The lighting outlets shall be so arranged that persons changing lamps or making repairs on the lighting system will not be endangered by live parts or other equipment. The points of control shall be so located that persons are not likely to come in contact with any live part or moving part of the equipment while turning on the lights.
Unguarded live parts above working space shall be maintained at elevations not less than specified in Table K-3.
| Nominal voltage between phases | Minimum elevation |
|---|---|
| 601-7,500 | 8 feet 6 inches. 1 |
| 7,501-35,000 | 9 feet. |
| Over 35kV | 9 feet + 0.37 inches per kV above 35kV. |
| 1 Note: For SI units: one inch = 25.4 mm; one foot = 0.3048 m. |
At least one entrance not less than 24 inches (610 mm) wide and 6 feet 6 inches (1.98 m) high shall be provided to give access to the working space about electric equipment. On switchboard and control panels exceeding 48 inches (1.22 m) in width, there shall be one entrance at each end of such board where practicable. Where bare energized parts at any voltage or insulated energized parts above 600 volts are located adjacent to such entrance, they shall be guarded.
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996]
A conductor used as a grounded conductor shall be identifiable and distinguishable from all other conductors. A conductor used as an equipment grounding conductor shall be identifiable and distinguishable from all other conductors.
No grounded conductor shall be attached to any terminal or lead so as to reverse designated polarity.
A grounding terminal or grounding-type device on a receptacle, cord connector, or attachment plug shall not be used for purposes other than grounding.
The employer shall use either ground fault circuit interrupters as specified in paragraph (b)(1)(ii) of this section or an assured equipment grounding conductor program as specified in paragraph (b)(1)(iii) of this section to protect employees on construction sites. These requirements are in addition to any other requirements for equipment grounding conductors.
All 120-volt, single-phase, 15- and 20-ampere receptacle outlets on construction sites, which are not a part of the permanent wiring of the building or structure and which are in use by employees, shall have approved ground-fault circuit interrupters for personnel protection. Receptacles on a two-wire, single-phase portable or vehicle-mounted generator rated not more than 5kW, where the circuit conductors of the generator are insulated from the generator frame and all other grounded surfaces, need not be protected with ground-fault circuit interrupters.
The employer shall establish and implement an assured equipment grounding conductor program on construction sites covering all cord sets, receptacles which are not a part of the building or structure, and equipment connected by cord and plug which are available for use or used by employees. This program shall comply with the following minimum requirements:
Outlet devices shall have an ampere rating not less than the load to be served and shall comply with the following:
A single receptacle installed on an individual branch circuit shall have an ampere rating of not less than that of the branch circuit.
Where connected to a branch circuit supplying two or more receptacles or outlets, receptacle ratings shall conform to the values listed in Table K-4.
The rating of an attachment plug or receptacle used for cord- and plug-connection of a motor to a branch circuit shall not exceed 15 amperes at 125 volts or 10 amperes at 250 volts if individual overload protection is omitted.
| Circuit rating amperes | Receptacle rating amperes |
|---|---|
| 15 | Not over 15. |
| 20 | 15 or 20. |
| 30 | 30. |
| 40 | 40 or 50. |
| 50 | 50. |
Conductors supported on poles shall provide a horizontal climbing space not less than the following:
300 volts or less—24 inches (610 mm); more than 300 volts—30 inches (762 mm).
with power conductors 300 volts or less—24 inches (610 mm); more than 300 volts—30 inches (762 mm).
Open conductors shall conform to the following minimum clearances:
Conductors shall have a clearance of at least 3 feet (914 mm) from windows, doors, fire escapes, or similar locations. Conductors run above the top level of a window are considered to be out of reach from that window and, therefore, do not have to be 3 feet (914 mm) away.
Conductors above roof space accessible to employees on foot shall have a clearance from the highest point of the roof surface of not less than 8 feet (2.44 m) vertical clearance for insulated conductors, not less than 10 feet (3.05 m) vertical or diagonal clearance for covered conductors, and not less than 15 feet (4.57 m) for bare conductors, except that:
Lamps for outdoor lighting shall be located below all live conductors, transformers, or other electric equipment, unless such equipment is controlled by a disconnecting means that can be locked in the open position or unless adequate clearances or other safeguards are provided for relamping operations.
Means shall be provided to disconnect all conductors in a building or other structure from the service-entrance conductors. The disconnecting means shall plainly indicate whether it is in the open or closed position and shall be installed at a readily accessible location nearest the point of entrance of the service-entrance conductors.
Each service disconnecting means shall simultaneously disconnect all ungrounded conductors.
Service-entrance conductors installed as open wires shall be guarded to make them accessible only to qualified persons.
Signs warning of high voltage shall be posted where unauthorized employees might come in contact with live parts.
Conductors and equipment shall be protected from overcurrent in accordance with their ability to safely conduct current. Conductors shall have sufficient ampacity to carry the load.
Except for motor-running overload protection, overcurrent devices shall not interrupt the continuity of the grounded conductor unless all conductors of the circuit are opened simultaneously.
Except for devices provided for current-limiting on the supply side of the service disconnecting means, all cartridge fuses which are accessible to other than qualified persons and all fuses and thermal cutouts on circuits over 150 volts to ground shall be provided with disconnecting means. This disconnecting means shall be installed so that the fuse or thermal cutout can be disconnected from its supply without disrupting service to equipment and circuits unrelated to those protected by the overcurrent device.
Overcurrent devices shall be readily accessible. Overcurrent devices shall not be located where they could create an employee safety hazard by being exposed to physical damage or located in the vicinity of easily ignitible material.
Fuses and circuit breakers shall be so located or shielded that employees will not be burned or otherwise injured by their operation.
Paragraphs (f)(1) through (f)(11) of this section contain grounding requirements for systems, circuits, and equipment.
The following systems which supply premises wiring shall be grounded:
All 3-wire DC systems shall have their neutral conductor grounded.
Two-wire DC systems operating at over 50 volts through 300 volts between conductors shall be grounded unless they are rectifier-derived from an AC system complying with paragraphs (f)(1)(iii), (f)(1)(iv), and (f)(1)(v) of this section.
circuits, less than 50 volts. AC circuits of less than 50 volts shall be grounded if they are installed as overhead conductors outside of buildings or if they are supplied by transformers and the transformer primary supply system is ungrounded or exceeds 150 volts to ground.
systems, 50 volts to 1000 volts. AC systems of 50 volts to 1000 volts shall be grounded under any of the following conditions, unless exempted by paragraph (f)(1)(v) of this section:
AC systems of 50 volts to 1000 volts are not required to be grounded if the system is separately derived and is supplied by a transformer that has a primary voltage rating less than 1000 volts, provided all of the following conditions are met:
Where paragraph (f)(1) of this section requires grounding of wiring systems whose power is derived from generator, transformer, or converter windings and has no direct electrical connection, including a solidly connected grounded circuit conductor, to supply conductors originating in another system, paragraph (f)(5) of this section shall also apply.
Under the following conditions, the frame of a portable generator need not be grounded and may serve as the grounding electrode for a system supplied by the generator:
Under the following conditions the frame of a vehicle may serve as the grounding electrode for a system supplied by a generator located on the vehicle:
A neutral conductor shall be bonded to the generator frame if the generator is a component of a separately derived system. No other conductor need be bonded to the generator frame.
For AC premises wiring systems the identified conductor shall be grounded.
For a grounded system, a grounding electrode conductor shall be used to connect both the equipment grounding conductor and the grounded circuit conductor to the grounding electrode. Both the equipment grounding conductor and the grounding electrode conductor shall be connected to the grounded circuit conductor on the supply side of the service disconnecting means, or on the supply side of the system disconnecting means or overcurrent devices if the system is separately derived.
For an ungrounded service-supplied system, the equipment grounding conductor shall be connected to the grounding electrode conductor at the service equipment. For an ungrounded separately derived system, the equipment grounding conductor shall be connected to the grounding electrode conductor at, or ahead of, the system disconnecting means or overcurrent devices.
The path to ground from circuits, equipment, and enclosures shall be permanent and continuous.
Metal cable trays, metal raceways, and metal enclosures for conductors shall be grounded, except that:
Metal enclosures for service equipment shall be grounded.
Exposed noncurrent-carrying metal parts of fixed equipment which may become energized shall be grounded under any of the following conditions:
Under any of the conditions described in paragraphs (f)(7)(iv)(A) through (f)(7)(iv)(C) of this section, exposed noncurrent-carrying metal parts of cord- and plug-connected equipment which may become energized shall be grounded:
The metal parts of the following nonelectrical equipment shall be grounded: Frames and tracks of electrically operated cranes; frames of nonelectrically driven elevator cars to which electric conductors are attached; hand-operated metal shifting ropes or cables of electric elevators, and metal partitions, grill work, and similar metal enclosures around equipment of over IkV between conductors.
Noncurrent-carrying metal parts of fixed equipment, if required to be grounded by this subpart, shall be grounded by an equipment grounding conductor which is contained within the same raceway, cable, or cord, or runs with or encloses the circuit conductors. For DC circuits only, the equipment grounding conductor may be run separately from the circuit conductors.
A conductor used for grounding fixed or movable equipment shall have capacity to conduct safely any fault current which may be imposed on it.
Electric equipment is considered to be effectively grounded if it is secured to, and in electrical contact with, a metal rack or structure that is provided for its support and the metal rack or structure is grounded by the method specified for the noncurrent-carrying metal parts of fixed equipment in paragraph (f)(8)(i) of this section. Metal car frames supported by metal hoisting cables attached to or running over metal sheaves or drums of grounded elevator machines are also considered to be effectively grounded.
If bonding conductors are used to assure electrical continuity, they shall have the capacity to conduct any fault current which may be imposed.
If made electrodes are used, they shall be free from nonconductive coatings, such as paint or enamel; and, if practicable, they shall be embedded below permanent moisture level. A single electrode consisting of a rod, pipe or plate which has a resistance to ground greater than 25 ohms shall be augmented by one additional electrode installed no closer than 6 feet (1.83 m) to the first electrode.
If high voltage systems are grounded, they shall comply with all applicable provisions of paragraphs (f)(1) through (f)(10) of this section as supplemented and modified by this paragraph (f)(11).
Systems supplying portable or mobile high voltage equipment, other than substations installed on a temporary basis, shall comply with the following:
All noncurrent-carrying metal parts of portable equipment and fixed equipment including their associated fences, housings, enclosures, and supporting structures shall be grounded. However, equipment which is guarded by location and isolated from ground need not be grounded. Additionally, pole-mounted distribution apparatus at a height exceeding 8 feet (2.44 m) above ground or grade level need not be grounded.
[51 FR 25318, July 11, 1986, as amended at 54 FR 24334, June 7, 1989; 61 FR 5510, Feb. 13, 1996]
The provisions of this paragraph do not apply to conductors which form an integral part of equipment such as motors, controllers, motor control centers and like equipment.
Metal raceways, cable armor, and other metal enclosures for conductors shall be metallically joined together into a continuous electric conductor and shall be so connected to all boxes, fittings, and cabinets as to provide effective electrical continuity.
No wiring systems of any type shall be installed in ducts used to transport dust, loose stock or flammable vapors. No wiring system of any type shall be installed in any duct used for vapor removal or in any shaft containing only such ducts.
The provisions of paragraph (a)(2) of this section apply to temporary electrical power and lighting wiring methods which may be of a class less than would be required for a permanent installation. Except as specifically modified in paragraph (a)(2) of this section, all other requirements of this subpart for permanent wiring shall apply to temporary wiring installations. Temporary wiring shall be removed immediately upon completion of construction or the purpose for which the wiring was installed.
For temporary wiring over 600 volts, nominal, fencing, barriers, or other effective means shall be provided to prevent access of other than authorized and qualified personnel.
All pull boxes, junction boxes, and fittings shall be provided with covers. If metal covers are used, they shall be grounded. In energized installations each outlet box shall have a cover, faceplate, or fixture canopy. Covers of outlet boxes having holes through which flexible cord pendants pass shall be provided with bushings designed for the purpose or shall have smooth, well-rounded surfaces on which the cords may bear.
Boxes shall provide a complete enclosure for the contained conductors or cables.
Boxes shall be closed by covers securely fastened in place. Underground box covers that weigh over 100 pounds (43.6 kg) meet this requirement. Covers for boxes shall be permanently marked “HIGH VOLTAGE.” The marking shall be on the outside of the box cover and shall be readily visible and legible.
Single-throw knife switches shall be so connected that the blades are dead when the switch is in the open position. Single-throw knife switches shall be so placed that gravity will not tend to close them. Single-throw knife switches approved for use in the inverted position shall be provided with a locking device that will ensure that the blades remain in the open position when so set. Double-throw knife switches may be mounted so that the throw will be either vertical or horizontal. However, if the throw is vertical, a locking device shall be provided to ensure that the blades remain in the open position when so set.
Switchboards that have any exposed live parts shall be located in permanently dry locations and accessible only to qualified persons. Panelboards shall be mounted in cabinets, cutout boxes, or enclosures designed for the purpose and shall be dead front. However, panelboards other than the dead front externally-operable type are permitted where accessible only to qualified persons. Exposed blades of knife switches shall be dead when open.
Switches, circuit breakers, and switchboards installed in wet locations shall be enclosed in weatherproof enclosures.
All conductors used for general wiring shall be insulated unless otherwise permitted in this subpart. The conductor insulation shall be of a type that is suitable for the voltage, operating temperature, and location of use. Insulated conductors shall be distinguishable by appropriate color or other means as being grounded conductors, ungrounded conductors, or equipment grounding conductors.
Flexible cords and cables shall be suitable for conditions of use and location. Flexible cords and cables shall be used only for:
If used as permitted in paragraphs (g)(1)(i)(C), (g)(1)(i)(F), or (g)(1)(i)(H) of this section, the flexible cord shall be equipped with an attachment plug and shall be energized from a receptacle outlet.
Unless necessary for a use permitted in paragraph (g)(1)(i) of this section, flexible cords and cables shall not be used:
A conductor of a flexible cord or cable that is used as a grounded conductor or an equipment grounding conductor shall be distinguishable from other conductors.
Type SJ, SJO, SJT, SJTO, S, SO, ST, and STO cords shall not be used unless durably marked on the surface with the type designation, size, and number of conductors.
Flexible cords shall be used only in continuous lengths without splice or tap. Hard service flexible cords No. 12 or larger may be repaired if spliced so that the splice retains the insulation, outer sheath properties, and usage characteristics of the cord being spliced.
Flexible cords shall be connected to devices and fittings so that strain relief is provided which will prevent pull from being directly transmitted to joints or terminal screws.
Flexible cords and cables shall be protected by bushings or fittings where passing through holes in covers, outlet boxes, or similar enclosures.
Fixture wires shall be suitable for the voltage, temperature, and location of use. A fixture wire which is used as a grounded conductor shall be identified.
Fixture wires may be used:
Fixture wires shall not be used as branch-circuit conductors except as permitted for Class 1 power-limited circuits.
Fixtures, lampholders, lamps, rosettes, and receptacles shall have no live parts normally exposed to employee contact. However, rosettes and cleat-type lampholders and receptacles located at least 8 feet (2.44 m) above the floor may have exposed parts.
Fixtures, lampholders, rosettes, and receptacles shall be securely supported. A fixture that weighs more than 6 pounds (2.72 kg) or exceeds 16 inches (406 mm) in any dimension shall not be supported by the screw shell of a lampholder.
Portable lamps shall be wired with flexible cord and an attachment plug of the polarized or grounding type. If the portable lamp uses an Edison-based lampholder, the grounded conductor shall be identified and attached to the screw shell and the identified blade of the attachment plug. In addition, portable handlamps shall comply with the following:
Lampholders of the screw-shell type shall be installed for use as lampholders only. Lampholders installed in wet or damp locations shall be of the weatherproof type.
Fixtures installed in wet or damp locations shall be identified for the purpose and shall be installed so that water cannot enter or accumulate in wireways, lampholders, or other electrical parts.
Receptacles, cord connectors, and attachment plugs shall be constructed so that no receptacle or cord connector will accept an attachment plug with a different voltage or current rating than that for which the device is intended. However, a 20-ampere T-slot receptacle or cord connector may accept a 15-ampere attachment plug of the same voltage rating. Receptacles connected to circuits having different voltages, frequencies, or types of current (ac or dc) on the same premises shall be of such design that the attachment plugs used on these circuits are not interchangeable.
A receptacle installed in a wet or damp location shall be designed for the location.
Appliances, other than those in which the current-carrying parts at high temperatures are necessarily exposed, shall have no live parts normally exposed to employee contact.
A means shall be provided to disconnect each appliance.
Each appliance shall be marked with its rating in volts and amperes or volts and watts.
This paragraph applies to motors, motor circuits, and controllers.
If specified that one piece of equipment shall be “in sight from” another piece of equipment, one shall be visible and not more than 50 feet (15.2 m) from the other.
The following paragraphs cover the installation of all transformers, except:
The operating voltage of exposed live parts of transformer installations shall be indicated by warning signs or visible markings on the equipment or structure.
Dry-type, high fire point liquid-insulated, and askarel-insulated transformers installed indoors and rated over 35 kV shall be in a vault.
If they present a fire hazard to employees, oil-insulated transformers installed indoors shall be in a vault.
Combustible material, combustible buildings and parts of buildings, fire escapes, and door and window openings shall be safeguarded from fires which may originate in oil-insulated transformers attached to or adjacent to a building or combustible material.
Transformer vaults shall be constructed so as to contain fire and combustible liquids within the vault and to prevent unauthorized access. Locks and latches shall be so arranged that a vault door can be readily opened from the inside.
Any pipe or duct system foreign to the vault installation shall not enter or pass through a transformer vault.
Materials shall not be stored in transformer vaults.
All capacitors, except surge capacitors or capacitors included as a component part of other apparatus, shall be provided with an automatic means of draining the stored charge and maintaining the discharged state after the capacitor is disconnected from its source of supply.
Capacitors rated over 600 volts, nominal, shall comply with the following additional requirements:
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996; 85 FR 8736, Feb. 18, 2020]
This paragraph applies to the installation of electric equipment and wiring used in connection with cranes, monorail hoists, hoists, and all runways.
A limit switch or other device shall be provided to prevent the load block from passing the safe upper limit of travel of any hoisting mechanism.
The dimension of the working space in the direction of access to live parts which may require examination, adjustment, servicing, or maintenance while alive shall be a minimum of 2 feet 6 inches (762 mm). Where controls are enclosed in cabinets, the door(s) shall open at least 90 degrees or be removable, or the installation shall provide equivalent access.
All exposed metal parts of cranes, monorail hoists, hoists and accessories including pendant controls shall be metallically joined together into a continuous electrical conductor so that the entire crane or hoist will be grounded in accordance with § 1926.404(f). Moving parts, other than removable accessories or attachments, having metal-to-metal bearing surfaces shall be considered to be electrically connected to each other through the bearing surfaces for grounding purposes. The trolley frame and bridge frame shall be considered as electrically grounded through the bridge and trolley wheels and its respective tracks unless conditions such as paint or other insulating materials prevent reliable metal-to-metal contact. In this case a separate bonding conductor shall be provided.
Elevators, escalators, and moving walks shall have a single means for disconnecting all ungrounded main power supply conductors for each unit.
If control panels are not located in the same space as the drive machine, they shall be located in cabinets with doors or panels capable of being locked closed.
A switch or circuit breaker shall be provided by which each resistance welder and its control equipment can be isolated from the supply circuit. The ampere rating of this disconnecting means shall not be less than the supply conductor ampacity.
A disconnecting means shall be provided in the supply circuit. The disconnecting means shall be operable from a location readily accessible from the X-ray control. For equipment connected to a 120-volt branch circuit of 30 amperes or less, a grounding-type attachment plug cap and receptacle of proper rating may serve as a disconnecting means.
If more than one piece of equipment is operated from the same high-voltage circuit, each piece or each group of equipment as a unit shall be provided with a high-voltage switch or equivalent disconnecting means. This disconnecting means shall be constructed, enclosed, or located so as to avoid contact by employees with its live parts.
Radiographic and fluoroscopic-type equipment shall be effectively enclosed or shall have interlocks that deenergize the equipment automatically to prevent ready access to live current-carrying parts.
This section sets forth requirements for electric equipment and wiring in locations which are classified depending on the properties of the flammable vapors, liquids or gases, or combustible dusts or fibers which may be present therein and the likelihood that a flammable or combustible concentration or quantity is present. Each room, section or area shall be considered individually in determining its classification. These hazardous (classified) locations are assigned six designations as follows:
Class I, Division 1
Class I, Division 2
Class II, Division 1
Class II, Division 2
Class III, Division l
Class III, Division 2
For definitions of these locations see § 1926.449. All applicable requirements in this subpart apply to all hazardous (classified) locations, unless modified by provisions of this section.
Equipment, wiring methods, and installations of equipment in hazardous (classified) locations shall be approved as intrinsically safe or approved for the hazardous (classified) location or safe for the hazardous (classified) location. Requirements for each of these options are as follows:
Equipment and associated wiring approved as intrinsically safe is permitted in any hazardous (classified) location included in its listing or labeling.
Equipment shall be approved not only for the class of location but also for the ignitible or combustible properties of the specific gas, vapor, dust, or fiber that will be present.
Equipment shall not be used unless it is marked to show the class, group, and operating temperature or temperature range, based on operation in a 40-degree C ambient, for which it is approved. The temperature marking shall not exceed the ignition temperature of the specific gas, vapor, or dust to be encountered. However, the following provisions modify this marking requirement for specific equipment:
Equipment which is safe for the location shall be of a type and design which the employer demonstrates will provide protection from the hazards arising from the combustibility and flammability of vapors, liquids, gases, dusts, or fibers.
All conduits shall be threaded and shall be made wrench-tight. Where it is impractical to make a threaded joint tight, a bonding jumper shall be utilized.
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996]
Above-ground conductors shall be installed in rigid metal conduit, in intermediate metal conduit, in cable trays, in cablebus, in other suitable raceways, or as open runs of metal-clad cable designed for the use and purpose. However, open runs of non-metallic-sheathed cable or of bare conductors or busbars may be installed in locations which are accessible only to qualified persons. Metallic shielding components, such as tapes, wires, or braids for conductors, shall be grounded. Open runs of insulated wires and cables having a bare lead sheath or a braided outer covering shall be supported in a manner designed to prevent physical damage to the braid or sheath.
Conductors emerging from the ground shall be enclosed in raceways. Raceways installed on poles shall be of rigid metal conduit, intermediate metal conduit, PVC schedule 80 or equivalent extending from the ground line up to a point 8 feet (2.44 m) above finished grade. Conductors entering a building shall be protected by an enclosure from the ground line to the point of entrance. Metallic enclosures shall be grounded.
Circuit breakers located indoors shall consist of metal-enclosed or fire-resistant, cell-mounted units. In locations accessible only to qualified personnel, open mounting of circuit breakers is permitted. A means of indicating the open and closed position of circuit breakers shall be provided.
Fused cutouts installed in buildings or transformer vaults shall be of a type identified for the purpose. They shall be readily accessible for fuse replacement.
A means shall be provided to completely isolate equipment for inspection and repairs. Isolating means which are not designed to interrupt the load current of the circuit shall be either interlocked with a circuit interrupter or provided with a sign warning against opening them under load.
A metallic enclosure shall be provided on the mobile machine for enclosing the terminals of the power cable. The enclosure shall include provisions for a solid connection for the ground wire(s) terminal to ground effectively the machine frame. The method of cable termination used shall prevent any strain or pull on the cable from stressing the electrical connections. The enclosure shall have provision for locking so only authorized qualified persons may open it and shall be marked with a sign warning of the presence of energized parts.
All energized switching and control parts shall be enclosed in effectively grounded metal cabinets or enclosures. Circuit breakers and protective equipment shall have the operating means projecting through the metal cabinet or enclosure so these units can be reset without locked doors being opened. Enclosures and metal cabinets shall be locked so that only authorized qualified persons have access and shall be marked with a sign warning of the presence of energized parts. Collector ring assemblies on revolving-type machines (shovels, draglines, etc.) shall be guarded.
The provisions of this paragraph apply to installation and use of high-voltage power distribution and utilization equipment which is associated with tunnels and which is portable and/or mobile, such as substations, trailers, cars, mobile shovels, draglines, hoists, drills, dredges, compressors, pumps, conveyors, and underground excavators.
Conductors in tunnels shall be installed in one or more of the following:
Conductors shall also be so located or guarded as to protect them from physical damage. Multiconductor portable cable may supply mobile equipment. An equipment grounding conductor shall be run with circuit conductors inside the metal raceway or inside the multiconductor cable jacket. The equipment grounding conductor may be insulated or bare.
Bare terminals of transformers, switches, motor controllers, and other equipment shall be enclosed to prevent accidental contact with energized parts. Enclosures for use in tunnels shall be drip-proof, weatherproof, or submersible as required by the environmental conditions.
A disconnecting means that simultaneously opens all ungrounded conductors shall be installed at each transformer or motor location.
All nonenergized metal parts of electric equipment and metal raceways and cable sheaths shall be grounded and bonded to all metal pipes and rails at the portal and at intervals not exceeding 1000 feet (305 m) throughout the tunnel.
Class 1, Class 2, or Class 3 remote control, signaling, or power-limited circuits are characterized by their usage and electrical power limitation which differentiates them from light and power circuits. These circuits are classified in accordance with their respective voltage and power limitations as summarized in paragraphs (b)(1)(i) through (b)(1)(iii) of this section.
The maximum circuit voltages in paragraphs (b)(1)(i) and (b)(1)(ii) of this section apply to sinusoidal AC or continuous DC power sources, and where wet contact occurrence is not likely.
A Class 2 or Class 3 power supply unit shall not be used unless it is durably marked where plainly visible to indicate the class of supply and its electrical rating.
These provisions for communication systems apply to such systems as central-station-connected and non-central-station-connected telephone circuits, radio receiving and transmitting equipment, and outside wiring for fire and burglar alarm, and similar central station systems. These installations need not comply with the provisions of §§ 1926.403 through 1926.408(b), except § 1926.404(c)(1)(ii) and § 1926.407.
Communication circuits so located as to be exposed to accidental contact with light or power conductors operating at over 300 volts shall have each circuit so exposed provided with an approved protector.
Each conductor of a lead-in from an outdoor antenna shall be provided with an antenna discharge unit or other means that will drain static charges from the antenna system.
Where practicable, communication conductors on poles shall be located below the light or power conductors. Communications conductors shall not be attached to a crossarm that carries light or power conductors.
Indoor antennas, lead-ins, and other communication conductors attached as open conductors to the inside of buildings shall be located at least 2 inches (50.8 mm) from conductors of any light or power or Class 1 circuits unless a special and equally protective method of conductor separation is employed.
Outdoor metal structures supporting antennas, as well as self-supporting antennas such as vertical rods or dipole structures, shall be located as far away from overhead conductors of electric light and power circuits of over 150 volts to ground as necessary to avoid the possibility of the antenna or structure falling into or making accidental contact with such circuits.
If exposed to contact with electric light or power conductors, the metal sheath of aerial cables entering buildings shall be grounded or shall be interrupted close to the entrance to the building by an insulating joint or equivalent device. Where protective devices are used, they shall be grounded.
Masts and metal structures supporting antennas shall be permanently and effectively grounded without splice or connection in the grounding conductor.
Transmitters shall be enclosed in a metal frame or grill or separated from the operating space by a barrier, all metallic parts of which are effectively connected to ground. All external metal handles and controls accessible to the operating personnel shall be effectively grounded. Unpowered equipment and enclosures shall be considered grounded where connected to an attached coaxial cable with an effectively grounded metallic shield.
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996]
In existing installations, no changes in circuit protection shall be made to increase the load in excess of the load rating of the circuit wiring.
When fuses are installed or removed with one or both terminals energized, special tools insulated for the voltage shall be used.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 55 FR 42328, Oct. 18, 1990; 58 FR 35179, June 30, 1993; 61 FR 9251, Mar. 7, 1996; 61 FR 41738, Aug. 12, 1996]
Controls that are to be deactivated during the course of work on energized or deenergized equipment or circuits shall be tagged.
Equipment or circuits that are deenergized shall be rendered inoperative and shall have tags attached at all points where such equipment or circuits can be energized.
Tags shall be placed to identify plainly the equipment or circuits being worked on.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 55 FR 42328, Oct. 18, 1990; 58 FR 35181, June 30, 1993; 61 FR 9251, Mar. 7, 1996; 61 FR 41739, Aug. 12, 1996]]
The employer shall ensure that all wiring components and utilization equipment in hazardous locations are maintained in a dust-tight, dust-ignition-proof, or explosion-proof condition, as appropriate. There shall be no loose or missing screws, gaskets, threaded connections, seals, or other impairments to a tight condition.
Metal raceways, cable armor, boxes, cable sheathing, cabinets, elbows, couplings, fittings, supports, and support hardware shall be of materials appropriate for the environment in which they are to be installed.
The definitions given in this section apply to the terms used in subpart K. The definitions given here for “approved” and “qualified person” apply, instead of the definitions given in § 1926.32, to the use of these terms in subpart K.
Acceptable. An installation or equipment is acceptable to the Assistant Secretary of Labor, and approved within the meaning of this subpart K:
Accepted. An installation is “accepted” if it has been inspected and found to be safe by a qualified testing laboratory.
Accessible. (As applied to wiring methods.) Capable of being removed or exposed without damaging the building structure or finish, or not permanently closed in by the structure or finish of the building. (See “concealed” and “exposed.”)
Accessible. (As applied to equipment.) Admitting close approach; not guarded by locked doors, elevation, or other effective means. (See “Readily accessible.”)
Ampacity. The current in amperes a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Appliances. Utilization equipment, generally other than industrial, normally built in standardized sizes or types, which is installed or connecetcd as a unit to perform one or more functions.
Approved. Acceptable to the authority enforcing this subpart. The authority enforcing this subpart is the Assistant Secretary of Labor for Occupational Safety and Health. The definition of “acceptable” indicates what is acceptable to the Assistant Secretary of Labor, and therefore approved within the meaning of this subpart.
Askarel. A generic term for a group of nonflammable synthetic chlorinated hydrocarbons used as electrical insulating media. Askarels of various compositional types are used. Under arcing conditions the gases produced, while consisting predominantly of noncombustible hydrogen chloride, can include varying amounts of combustible gases depending upon the askarel type.
Attachment plug (Plug cap)(Cap). A device which, by insertion in a receptacle, establishes connection between the conductors of the attached flexible cord and the conductors connected permanently to the receptacle.
Automatic. Self-acting, operating by its own mechanism when actuated by some impersonal influence, as for example, a change in current strength, pressure, temperature, or mechanical configuration.
Bare conductor. See “Conductor.”
Bonding. The permanent joining of metallic parts to form an electrically conductive path which will assure electrical continuity and the capacity to conduct safely any current likely to be imposed.
Bonding jumper. A reliable conductor to assure the required electrical conductivity between metal parts required to be electrically connected.
Branch circuit. The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s).
Building. A structure which stands alone or which is cut off from adjoining structures by fire walls with all openings therein protected by approved fire doors.
Cabinet. An enclosure designed either for surface or flush mounting, and provided with a frame, mat, or trim in which a swinging door or doors are or may be hung.
Certified. Equipment is “certified” if it:
Circuit breaker —
Class I locations. Class I locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I locations include the following:
Class II locations. Class II locations are those that are hazardous because of the presence of combustible dust. Class II locations include the following:
Class III locations. Class III locations are those that are hazardous because of the presence of easily ignitible fibers or flyings but in which such fibers or flyings are not likely to be in suspension in the air in quantities sufficient to produce ignitible mixtures. Class 111 locations include the following:
Collector ring. A collector ring is an assembly of slip rings for transferring electrical energy from a stationary to a rotating member.
Concealed. Rendered inaccessible by the structure or finish of the building. Wires in concealed raceways are considered concealed, even though they may become accessible by withdrawing them. [See “Accessible. (As applied to wiring methods.)”]
Conductor —
A conductor having no covering or electrical insulation whatsoever.
A conductor encased within material of composition or thickness that is not recognized as electrical insulation.
A conductor encased within material of composition and thickness that is recognized as electrical insulation.
Controller. A device or group of devices that serves to govern, in some predetermined manner, the electric power delivered to the apparatus to which it is connected.
Covered conductor. See “Conductor.”
Cutout. (Over 600 volts, nominal.) An assembly of a fuse support with either a fuseholder, fuse carrier, or disconnecting blade. The fuseholder or fuse carrier may include a conducting element (fuse link), or may act as the disconnecting blade by the inclusion of a nonfusible member.
Cutout box. An enclosure designed for surface mounting and having swinging doors or covers secured directly to and telescoping with the walls of the box proper. (See “Cabinet.”)
Damp location. See “Location.”
Dead front. Without live parts exposed to a person on the operating side of the equipment.
Device. A unit of an electrical system which is intended to carry but not utilize electric energy.
Disconnecting means. A device, or group of devices, or other means by which the conductors of a circuit can be disconnected from their source of supply.
Disconnecting (or Isolating) switch. (Over 600 volts, nominal.) A mechanical switching device used for isolating a circuit or equipment from a source of power.
Dry location. See “Location.”
Enclosed. Surrounded by a case, housing, fence or walls which will prevent persons from accidentally contacting energized parts.
Enclosure. The case or housing of apparatus, or the fence or walls surrounding an installation to prevent personnel from accidentally contacting energized parts, or to protect the equipment from physical damage.
Equipment. A general term including material, fittings, devices, appliances, fixtures, apparatus, and the like, used as a part of, or in connection with, an electrical installation.
Equipment grounding conductor. See “Grounding conductor, equipment.”
Explosion-proof apparatus. Apparatus enclosed in a case that is capable of withstanding an explosion of a specified gas or vapor which may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and which operates at such an external temperature that it will not ignite a surrounding flammable atmosphere.
Exposed. (As applied to live parts.) Capable of being inadvertently touched or approached nearer than a safe distance by a person. It is applied to parts not suitably guarded, isolated, or insulated. (See “Accessible and “Concealed.”)
Exposed. (As applied to wiring methods.) On or attached to the surface or behind panels designed to allow access. [See “Accessible. (As applied to wiring methods.)”]
Exposed. (For the purposes of § 1926.408(d), Communications systems.) Where the circuit is in such a position that in case of failure of supports or insulation, contact with another circuit may result.
Externally operable. Capable of being operated without exposing the operator to contact with live parts.
Feeder. All circuit conductors between the service equipment, or the generator switchboard of an isolated plant, and the final branch-circuit overcurrent device.
Festoon lighting. A string of outdoor lights suspended between two points more than 15 feet (4.57 m) apart.
Fitting. An accessory such as a locknut, bushing, or other part of a wiring system that is intended primarily to perform a mechanical rather than an electrical function.
Fuse. (Over 600 volts, nominal.) An overcurrent protective device with a circuit opening fusible part that is heated and severed by the passage of overcurrent through it. A fuse comprises all the parts that form a unit capable of performing the prescribed functions. It may or may not be the complete device necessary to connect it into an electrical circuit.
Ground. A conducting connection, whether intentional or accidental, between an electrical circuit or equipment and the earth, or to some conducting body that serves in place of the earth.
Grounded. Connected to earth or to some conducting body that serves in place of the earth.
Grounded, effectively (Over 600 volts, nominal.) Permanently connected to earth through a ground connection of sufficiently low impedance and having sufficient ampacity that ground fault current which may occur cannot build up to voltages dangerous to personnel.
Grounded conductor. A system or circuit conductor that is intentionally grounded.
Grounding conductor. A conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode or electrodes.
Grounding conductor, equipment. The conductor used to connect the noncurrent-carrying metal parts of equipment, raceways, and other enclosures to the system grounded conductor and/or the grounding electrode conductor at the service equipment or at the source of a separately derived system.
Grounding electrode conductor. The conductor used to connect the grounding electrode to the equipment grounding conductor and/or to the grounded conductor of the circuit at the service equipment or at the source of a separately derived system.
Ground-fault circuit interrupter. A device for the protection of personnel that functions to deenergize a circuit or portion thereof within an established period of time when a current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit.
Guarded. Covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers, casings, barriers, rails, screens, mats, or platforms to remove the likelihood of approach to a point of danger or contact by persons or objects.
Hoistway. Any shaftway, hatchway, well hole, or other vertical opening or space in which an elevator or dumbwaiter is designed to operate.
Identified (conductors or terminals). Identified, as used in reference to a conductor or its terminal, means that such conductor or terminal can be recognized as grounded.
Identified (for the use). Recognized as suitable for the specific purpose, function, use, environment, application, etc. where described as a requirement in this standard. Suitability of equipment for a specific purpose, environment, or application is determined by a qualified testing laboratory where such identification includes labeling or listing.
Insulated conductor. See “ Conductor. ”
Interrupter switch. (Over 600 volts, nominal.) A switch capable of making, carrying, and interrupting specified currents.
Intrinsically safe equipment and associated wiring. Equipment and associated wiring in which any spark or thermal effect, produced either normally or in specified fault conditions, is incapable, under certain prescribed test conditions, of causing ignition of a mixture of flammable or combustible material in air in its most easily ignitible concentration.
Isolated. Not readily accessible to persons unless special means for access are used.
Isolated power system. A system comprising an isolating transformer or its equivalent, a line isolation monitor, and its ungrounded circuit conductors.
Labeled. Equipment or materials to which has been attached a label, symbol or other identifying mark of a qualified testing laboratory which indicates compliance with appropriate standards or performance in a specified manner.
Lighting outlet. An outlet intended for the direct connection of a lampholder, a lighting fixture, or a pendant cord terminating in a lampholder.
Listed. Equipment or materials included in a list published by a qualified testing laboratory whose listing states either that the equipment or material meets appropriate standards or has been tested and found suitable for use in a specified manner.
Location —
Partially protected locations under canopies, marquees, roofed open porches, and like locations, and interior locations subject to moderate degrees of moisture, such as some basements.
A location not normally subject to dampness or wetness. A location classified as dry may be temporarily subject to dampness or wetness, as in the case of a building under construction.
Installations underground or in concrete slabs or masonry in direct contact with the earth, and locations subject to saturation with water or other liquids, such as locations exposed to weather and unprotected.
Mobile X-ray. X-ray equipment mounted on a permanent base with wheels and/or casters for moving while completely assembled.
Motor control center. An assembly of one or more enclosed sections having a common power bus and principally containing motor control units.
Outlet. A point on the wiring system at which current is taken to supply utilization equipment.
Overcurrent. Any current in excess of the rated current of equipment or the ampacity of a conductor. It may result from overload (see definition), short circuit, or ground fault. A current in excess of rating may be accommodated by certain equipment and conductors for a given set of conditions. Hence the rules for overcurrent protection are specific for particular situations.
Overload. Operation of equipment in excess of normal, full load rating, or of a conductor in excess of rated ampacity which, when it persists for a sufficient length of time, would cause damage or dangerous overheating. A fault, such as a short circuit or ground fault, is not an overload. (See “Overcurrent.” )
Panelboard. A single panel or group of panel units designed for assembly in the form of a single panel; including buses, automatic overcurrent devices, and with or without switches for the control of light, heat, or power circuits; designed to be placed in a cabinet or cutout box placed in or against a wall or partition and accessible only from the front. (See “ Switchboard. ”)
Portable X-ray. X-ray equipment designed to be hand-carried.
Power fuse. (Over 600 volts, nominal.) See “Fuse.”
Power outlet. An enclosed assembly which may include receptacles, circuit breakers, fuseholders, fused switches, buses and watt-hour meter mounting means; intended to serve as a means for distributing power required to operate mobile or temporarily installed equipment.
Premises wiring system. That interior and exterior wiring, including power, lighting, control, and signal circuit wiring together with all of its associated hardware, fittings, and wiring devices, both permanently and temporarily installed, which extends from the load end of the service drop, or load end of the service lateral conductors to the outlet(s). Such wiring does not include wiring internal to appliances, fixtures, motors, controllers, motor control centers, and similar equipment.
Qualified person. One familiar with the construction and operation of the equipment and the hazards involved.
Qualified testing laboratory. A properly equipped and staffed testing laboratory which has capabilities for and which provides the following services:
Raceway. A channel designed expressly for holding wires, cables, or busbars, with additional functions as permitted in this subpart. Raceways may be of metal or insulating material, and the term includes rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, liquidtight flexible metal conduit, flexible metallic tubing, flexible metal conduit, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface raceways, wireways, and busways.
Readily accessible. Capable of being reached quickly for operation, renewal, or inspections, without requiring those to whom ready access is requisite to climb over or remove obstacles or to resort to portable ladders, chairs, etc. (See “Accessible.” )
Receptacle. A receptacle is a contact device installed at the outlet for the connection of a single attachment plug. A single receptacle is a single contact device with no other contact device on the same yoke. A multiple receptacle is a single device containing two or more receptacles.
Receptacle outlet. An outlet where one or more receptacles are installed.
Remote-control circuit. Any electric circuit that controls any other circuit through a relay or an equivalent device.
Sealable equipment. Equipment enclosed in a case or cabinet that is provided with a means of sealing or locking so that live parts cannot be made accessible without opening the enclosure. The equipment may or may not be operable without opening the enclosure.
Separately derived system. A premises wiring system whose power is derived from generator, transformer, or converter windings and has no direct electrical connection, including a solidly connected grounded circuit conductor, to supply conductors originating in another system.
Service. The conductors and equipment for delivering energy from the electricity supply system to the wiring system of the premises served.
Service conductors. The supply conductors that extend from the street main or from transformers to the service equipment of the premises supplied.
Service drop. The overhead service conductors from the last pole or other aerial support to and including the splices, if any, connecting to the service-entrance conductors at the building or other structure.
Service-entrance conductors, overhead system. The service conductors between the terminals of the service equipment and a point usually outside the building, clear of building walls, where joined by tap or splice to the service drop.
Service-entrance conductors, underground system. The service conductors between the terminals of the service equipment and the point of connection to the service lateral. Where service equipment is located outside the building walls, there may be no service-entrance conductors, or they may be entirely outside the building.
Service equipment. The necessary equipment, usually consisting of a circuit breaker or switch and fuses, and their accessories, located near the point of entrance of supply conductors to a building or other structure, or an otherwise defined area, and intended to constitute the main control and means of cutoff of the supply.
Service raceway. The raceway that encloses the service-entrance conductors.
Signaling circuit. Any electric circuit that energizes signaling equipment.
Switchboard. A large single panel, frame, or assembly of panels which have switches, buses, instruments, overcurrent and other protective devices mounted on the face or back or both. Switchboards are generally accessible from the rear as well as from the front and are not intended to be installed in cabinets. (See “Panelboard.”)
Switches —
A switch intended for use in general distribution and branch circuits. It is rated in amperes, and it is capable of interrupting its rated current at its rated voltage.
A form of general-use switch so constructed that it can be installed in flush device boxes or on outlet box covers, or otherwise used in conjunction with wiring systems recognized by this subpart.
A switch intended for isolating an electric circuit from the source of power. It has no interrupting rating, and it is intended to be operated only after the circuit has been opened by some other means.
A switch, rated in horsepower, capable of interrupting the maximum operating overload current of a motor of the same horsepower rating as the switch at the rated voltage.
Switching devices. (Over 600 volts, nominal.) Devices designed to close and/or open one or more electric circuits. Included in this category are circuit breakers, cutouts, disconnecting (or isolating) switches, disconnecting means, and interrupter switches.
Transportable X-ray. X-ray equipment installed in a vehicle or that may readily be disassembled for transport in a vehicle.
Utilization equipment. Utilization equipment means equipment which utilizes electric energy for mechanical, chemical, heating, lighting, or similar useful purpose.
Utilization system. A utilization system is a system which provides electric power and light for employee workplaces, and includes the premises wiring system and utilization equipment.
Ventilated. Provided with a means to permit circulation of air sufficient to remove an excess of heat, fumes, or vapors.
Volatile flammable liquid. A flammable liquid having a flash point below 38 degrees C (100 degrees F) or whose temperature is above its flash point, or a Class II combustible liquid having a vapor pressure not exceeding 40 psia (276 kPa) at 38 °C (100 °F) whose temperature is above its flash point.
Voltage. (Of a circuit.) The greatest root-mean-square (effective) difference of potential between any two conductors of the circuit concerned.
Voltage, nominal. A nominal value assigned to a circuit or system for the purpose of conveniently designating its voltage class (as 120/240, 480Y/277, 600, etc.). The actual voltage at which a circuit operates can vary from the nominal within a range that permits satisfactory operation of equipment.
Voltage to ground. For grounded circuits, the voltage between the given conductor and that point or conductor of the circuit that is grounded; for ungrounded circuits, the greatest voltage between the given conductor and any other conductor of the circuit.
Watertight. So constructed that moisture will not enter the enclosure.
Weatherproof. So constructed or protected that exposure to the weather will not interfere with successful operation. Rainproof, raintight, or watertight equipment can fulfill the requirements for weatherproof where varying weather conditions other than wetness, such as snow, ice, dust, or temperature extremes, are not a factor.
Wet location. See “Location.”
This subpart applies to all scaffolds used in workplaces covered by this part. It does not apply to crane or derrick suspended personnel platforms. The criteria for aerial lifts are set out exclusively in § 1926.453.
Adjustable suspension scaffold means a suspension scaffold equipped with a hoist(s) that can be operated by an employee(s) on the scaffold.
Bearer (putlog) means a horizontal transverse scaffold member (which may be supported by ledgers or runners) upon which the scaffold platform rests and which joins scaffold uprights, posts, poles, and similar members.
Boatswains' chair means a single-point adjustable suspension scaffold consisting of a seat or sling designed to support one employee in a sitting position.
Body belt (safety belt) means a strap with means both for securing it about the waist and for attaching it to a lanyard, lifeline, or deceleration device.
Body harness means a design of straps which may be secured about the employee in a manner to distribute the fall arrest forces over at least the thighs, pelvis, waist, chest and shoulders, with means for attaching it to other components of a personal fall arrest system.
Brace means a rigid connection that holds one scaffold member in a fixed position with respect to another member, or to a building or structure.
Bricklayers' square scaffold means a supported scaffold composed of framed squares which support a platform.
Carpenters' bracket scaffold means a supported scaffold consisting of a platform supported by brackets attached to building or structural walls.
Catenary scaffold means a suspension scaffold consisting of a platform supported by two essentially horizontal and parallel ropes attached to structural members of a building or other structure. Additional support may be provided by vertical pickups.
Chimney hoist means a multi-point adjustable suspension scaffold used to provide access to work inside chimneys. (See “Multi-point adjustable suspension scaffold”.)
Cleat means a structural block used at the end of a platform to prevent the platform from slipping off its supports. Cleats are also used to provide footing on sloped surfaces such as crawling boards.
Competent person means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.
Continuous run scaffold (Run scaffold) means a two- point or multi-point adjustable suspension scaffold constructed using a series of interconnected braced scaffold members or supporting structures erected to form a continuous scaffold.
Coupler means a device for locking together the tubes of a tube and coupler scaffold.
Crawling board (chicken ladder) means a supported scaffold consisting of a plank with cleats spaced and secured to provide footing, for use on sloped surfaces such as roofs.
Deceleration device means any mechanism, such as a rope grab, rip-stitch lanyard, specially-woven lanyard, tearing or deforming lanyard, or automatic self-retracting lifeline lanyard, which dissipates a substantial amount of energy during a fall arrest or limits the energy imposed on an employee during fall arrest.
Double pole (independent pole) scaffold means a supported scaffold consisting of a platform(s) resting on cross beams (bearers) supported by ledgers and a double row of uprights independent of support (except ties, guys, braces) from any structure.
Equivalent means alternative designs, materials or methods to protect against a hazard which the employer can demonstrate will provide an equal or greater degree of safety for employees than the methods, materials or designs specified in the standard.
Exposed power lines means electrical power lines which are accessible to employees and which are not shielded from contact. Such lines do not include extension cords or power tool cords.
Eye or Eye splice means a loop with or without a thimble at the end of a wire rope.
Fabricated decking and planking means manufactured platforms made of wood (including laminated wood, and solid sawn wood planks), metal or other materials.
Fabricated frame scaffold (tubular welded frame scaffold) means a scaffold consisting of a platform(s) supported on fabricated end frames with integral posts, horizontal bearers, and intermediate members.
Failure means load refusal, breakage, or separation of component parts. Load refusal is the point where the ultimate strength is exceeded.
Float (ship) scaffold means a suspension scaffold consisting of a braced platform resting on two parallel bearers and hung from overhead supports by ropes of fixed length.
Form scaffold means a supported scaffold consisting of a platform supported by brackets attached to formwork.
Guardrail system means a vertical barrier, consisting of, but not limited to, toprails, midrails, and posts, erected to prevent employees from falling off a scaffold platform or walkway to lower levels.
Hoist means a manual or power-operated mechanical device to raise or lower a suspended scaffold.
Horse scaffold means a supported scaffold consisting of a platform supported by construction horses (saw horses). Horse scaffolds constructed of metal are sometimes known as trestle scaffolds.
Independent pole scaffold (see “Double pole scaffold”).
Interior hung scaffold means a suspension scaffold consisting of a platform suspended from the ceiling or roof structure by fixed length supports.
Ladder jack scaffold means a supported scaffold consisting of a platform resting on brackets attached to ladders.
Ladder stand means a mobile, fixed-size, self-supporting ladder consisting of a wide flat tread ladder in the form of stairs.
Landing means a platform at the end of a flight of stairs.
Large area scaffold means a pole scaffold, tube and coupler scaffold, systems scaffold, or fabricated frame scaffold erected over substantially the entire work area. For example: a scaffold erected over the entire floor area of a room.
Lean-to scaffold means a supported scaffold which is kept erect by tilting it toward and resting it against a building or structure.
Lifeline means a component consisting of a flexible line that connects to an anchorage at one end to hang vertically (vertical lifeline), or that connects to anchorages at both ends to stretch horizontally (horizontal lifeline), and which serves as a means for connecting other components of a personal fall arrest system to the anchorage.
Lower levels means areas below the level where the employee is located and to which an employee can fall. Such areas include, but are not limited to, ground levels, floors, roofs, ramps, runways, excavations, pits, tanks, materials, water, and equipment.
Masons' adjustable supported scaffold (see “Self-contained adjustable scaffold”).
Masons' multi-point adjustable suspension scaffold means a continuous run suspension scaffold designed and used for masonry operations.
Maximum intended load means the total load of all persons, equipment, tools, materials, transmitted loads, and other loads reasonably anticipated to be applied to a scaffold or scaffold component at any one time.
Mobile scaffold means a powered or unpowered, portable, caster or wheel-mounted supported scaffold.
Multi-level suspended scaffold means a two-point or multi-point adjustable suspension scaffold with a series of platforms at various levels resting on common stirrups.
Multi-point adjustable suspension scaffold means a suspension scaffold consisting of a platform(s) which is suspended by more than two ropes from overhead supports and equipped with means to raise and lower the platform to desired work levels. Such scaffolds include chimney hoists.
Needle beam scaffold means a platform suspended from needle beams.
Open sides and ends means the edges of a platform that are more than 14 inches (36 cm) away horizontally from a sturdy, continuous, vertical surface (such as a building wall) or a sturdy, continuous horizontal surface (such as a floor), or a point of access. Exception: For plastering and lathing operations the horizontal threshold distance is 18 inches (46 cm).
Outrigger means the structural member of a supported scaffold used to increase the base width of a scaffold in order to provide support for and increased stability of the scaffold.
Outrigger beam (Thrustout) means the structural member of a suspension scaffold or outrigger scaffold which provides support for the scaffold by extending the scaffold point of attachment to a point out and away from the structure or building.
Outrigger scaffold means a supported scaffold consisting of a platform resting on outrigger beams (thrustouts) projecting beyond the wall or face of the building or structure, the inboard ends of which are secured inside the building or structure.
Overhand bricklaying means the process of laying bricks and masonry units such that the surface of the wall to be jointed is on the opposite side of the wall from the mason, requiring the mason to lean over the wall to complete the work. It includes mason tending and electrical installation incorporated into the brick wall during the overhand bricklaying process.
Personal fall arrest system means a system used to arrest an employee's fall. It consists of an anchorage, connectors, a body belt or body harness and may include a lanyard, deceleration device, lifeline, or combinations of these.
Platform means a work surface elevated above lower levels. Platforms can be constructed using individual wood planks, fabricated planks, fabricated decks, and fabricated platforms.
Pole scaffold (see definitions for “Single-pole scaffold” and “Double (independent) pole scaffold”).
Power operated hoist means a hoist which is powered by other than human energy.
Pump jack scaffold means a supported scaffold consisting of a platform supported by vertical poles and movable support brackets.
Qualified means one who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated his/her ability to solve or resolve problems related to the subject matter, the work, or the project.
Rated load means the manufacturer's specified maximum load to be lifted by a hoist or to be applied to a scaffold or scaffold component.
Repair bracket scaffold means a supported scaffold consisting of a platform supported by brackets which are secured in place around the circumference or perimeter of a chimney, stack, tank or other supporting structure by one or more wire ropes placed around the supporting structure.
Roof bracket scaffold means a rooftop supported scaffold consisting of a platform resting on angular-shaped supports.
Runner (ledger or ribbon) means the lengthwise horizontal spacing or bracing member which may support the bearers.
Scaffold means any temporary elevated platform (supported or suspended) and its supporting structure (including points of anchorage), used for supporting employees or materials or both.
Self-contained adjustable scaffold means a combination supported and suspension scaffold consisting of an adjustable platform(s) mounted on an independent supporting frame(s) not a part of the object being worked on, and which is equipped with a means to permit the raising and lowering of the platform(s). Such systems include rolling roof rigs, rolling outrigger systems, and some masons' adjustable supported scaffolds.
Shore scaffold means a supported scaffold which is placed against a building or structure and held in place with props.
Single-point adjustable suspension scaffold means a suspension scaffold consisting of a platform suspended by one rope from an overhead support and equipped with means to permit the movement of the platform to desired work levels.
Single-pole scaffold means a supported scaffold consisting of a platform(s) resting on bearers, the outside ends of which are supported on runners secured to a single row of posts or uprights, and the inner ends of which are supported on or in a structure or building wall.
Stair tower (Scaffold stairway/tower) means a tower comprised of scaffold components and which contains internal stairway units and rest platforms. These towers are used to provide access to scaffold platforms and other elevated points such as floors and roofs.
Stall load means the load at which the prime-mover of a power-operated hoist stalls or the power to the prime-mover is automatically disconnected.
Step, platform, and trestle ladder scaffold means a platform resting directly on the rungs of step ladders or trestle ladders.
Stilts means a pair of poles or similar supports with raised footrests, used to permit walking above the ground or working surface.
Stonesetters' multi-point adjustable suspension scaffold means a continuous run suspension scaffold designed and used for stonesetters' operations.
Supported scaffold means one or more platforms supported by outrigger beams, brackets, poles, legs, uprights, posts, frames, or similar rigid support.
Suspension scaffold means one or more platforms suspended by ropes or other non-rigid means from an overhead structure(s).
System scaffold means a scaffold consisting of posts with fixed connection points that accept runners, bearers, and diagonals that can be interconnected at predetermined levels.
Tank builders' scaffold means a supported scaffold consisting of a platform resting on brackets that are either directly attached to a cylindrical tank or attached to devices that are attached to such a tank.
Top plate bracket scaffold means a scaffold supported by brackets that hook over or are attached to the top of a wall. This type of scaffold is similar to carpenters' bracket scaffolds and form scaffolds and is used in residential construction for setting trusses.
Tube and coupler scaffold means a supported or suspended scaffold consisting of a platform(s) supported by tubing, erected with coupling devices connecting uprights, braces, bearers, and runners.
Tubular welded frame scaffold (see “Fabricated frame scaffold”).
Two-point suspension scaffold (swing stage) means a suspension scaffold consisting of a platform supported by hangers (stirrups) suspended by two ropes from overhead supports and equipped with means to permit the raising and lowering of the platform to desired work levels.
Unstable objects means items whose strength, configuration, or lack of stability may allow them to become dislocated and shift and therefore may not properly support the loads imposed on them. Unstable objects do not constitute a safe base support for scaffolds, platforms, or employees. Examples include, but are not limited to, barrels, boxes, loose brick, and concrete blocks.
Vertical pickup means a rope used to support the horizontal rope in catenary scaffolds.
Walkway means a portion of a scaffold platform used only for access and not as a work level.
Window jack scaffold means a platform resting on a bracket or jack which projects through a window opening.
[61 FR 46104, Aug. 30, 1996, as amended at 75 FR 48133, Aug. 9, 2010]
This section does not apply to aerial lifts, the criteria for which are set out exclusively in § 1926.453.
Exception to paragraph (b)(1): The requirement in paragraph (b)(1) to provide full planking or decking does not apply to platforms used solely as walkways or solely by employees performing scaffold erection or dismantling. In these situations, only the planking that the employer establishes is necessary to provide safe working conditions is required.
This paragraph applies to scaffold access for all employees. Access requirements for employees erecting or dismantling supported scaffolds are specifically addressed in paragraph (e)(9) of this section.
| Insulated lines voltage | Minimum distance | Alternatives |
|---|---|---|
| Less than 300 volts | 3 feet (0.9 m) | |
| 300 volts to 50 kv | 10 feet (3.1m) | |
| More than 50 kv | 10 feet (3.1 m) plus 0.4 inches (1.0 cm) for each 1 kv over 50 kv | 2 times the length of the line insulator, but never less than 10 feet (3.1 m). |
| Uninsulated lines voltage | Minimum distance | Alternatives |
|---|---|---|
| Less than 50 kv | 10 feet (3.1 m) | |
| More than 50 kv | 10 feet (3.1 m) plus 0.4 inches (1.0 cm) for each 1 kv over 50 kv | 2 times the length of the line insulator, but never less than 10 feet (3.1 m). |
[61 FR 46107, Aug. 30, 1996, as corrected and amended at 61 FR 59831, 59832, Nov. 25, 1996]
Effective Date Note:
At 61 FR 59832, Nov. 25, 1996, § 1926.451(b)(2)(i) was amended and certain requirements stayed until Nov. 25, 1997, or until further rulemaking has been completed, whichever is later.
In addition to the applicable requirements of § 1926.451, the following requirements apply to the specific types of scaffolds indicated. Scaffolds not specifically addressed by § 1926.452, such as but not limited to systems scaffolds, must meet the requirements of § 1926.451.
The following requirements do not apply to two-point adjustable suspension scaffolds used as masons' or stonesetters' scaffolds. Such scaffolds are covered by paragraph (q) of this section.
Stilts, when used, shall be used in accordance with the following requirements:
[61 FR 46104, Aug. 30, 1996, as amended at 85 FR 8736, Feb. 18, 2020]
Aerial equipment may be made of metal, wood, fiberglass reinforced plastic (FRP), or other material; may be powered or manually operated; and are deemed to be aerial lifts whether or not they are capable of rotating about a substantially vertical axis.
Aerial ladders shall be secured in the lower traveling position by the locking device on top of the truck cab, and the manually operated device at the base of the ladder before the truck is moved for highway travel.
All electrical tests shall conform to the requirements of ANSI A92.2-1969 section 5. However equivalent d.c.; voltage tests may be used in lieu of the a.c. voltage specified in A92.2-1969; d.c. voltage tests which are approved by the equipment manufacturer or equivalent entity shall be considered an equivalent test for the purpose of this paragraph (b)(3).
The provisions of the American National Standards Institute standard ANSI A92.2-1969, section 4.9 Bursting Safety Factor shall apply to all critical hydraulic and pneumatic components. Critical components are those in which a failure would result in a free fall or free rotation of the boom. All noncritical components shall have a bursting safety factor of at least 2 to 1.
All welding shall conform to the following standards as applicable:
[61 FR 46116, Aug. 30, 1996; 61 FR 59832, Nov. 25, 1996, as amended at 69 FR 18803, Apr. 9, 2004]
This section supplements and clarifies the requirements of § 1926.21(b)(2) as these relate to the hazards of work on scaffolds.
This appendix provides non-mandatory guidelines to assist employers in complying with the requirements of subpart L of this part. An employer may use these guidelines and tables as a starting point for designing scaffold systems. However, the guidelines do not provide all the information necessary to build a complete system, and the employer is still responsible for designing and assembling these components in such a way that the completed system will meet the requirements of § 1926.451(a). Scaffold components which are not selected and loaded in accordance with this Appendix, and components for which no specific guidelines or tables are given in this appendix (e.g., joints, ties, components for wood pole scaffolds more than 60 feet in height, components for heavy-duty horse scaffolds, components made with other materials, and components with other dimensions, etc.) must be designed and constructed in accordance with the capacity requirements of § 1926.451(a), and loaded in accordance with § 1926.451(d)(1).
Index to appendix A for Subpart L
1. General guidelines and tables.
2. Specific guidelines and tables.
Single-pole wood pole scaffolds.
Independent wood pole scaffolds.
1. General Guidelines and Tables
| Maximum intended nominal load (lb/ft 2 ) | Maximum permissible span using full thickness undressed lumber (ft) | Maximum permissible span using nominal thickness lumber (ft) |
|---|---|---|
| 25 | 10 | 8 |
| 50 | 8 | 6 |
| 75 | 6 |
| Rated load capacity | Intended load |
|---|---|
| Light-duty | • 25 pounds per square foot applied uniformly over the entire span area. |
| Medium-duty | • 50 pounds per square foot applied uniformly over the entire span area. |
| Heavy-duty | • 75 pounds per square foot applied uniformly over the entire span area. |
| One-person | • 250 pounds placed at the center of the span (total 250 pounds). |
| Two-person | • 250 pounds placed 18 inches to the left and right of the center of the span (total 500 pounds). |
| Three-person | • 250 pounds placed at the center of the span and 250 pounds placed 18 inches to the left and right of the center of the span (total 750 pounds). |
1 1/4 inch × 1/8 inch structural angle iron; or
1 inch ×.070 inch wall steel tubing; or 1.990 inch ×.058 inch wall aluminum tubing.
1 1/4 inch × 1 1/4 inch × 1/8 inch structural angle iron; or
1 inch ×.070 inch wall steel tubing; or
1.990 inch ×.058 inch wall aluminum tubing.
1 1/4 inch × 1 1/4 inch structural angle iron; or
1 inch ×.070 inch wall steel tubing; or
1.990 inch ×.058 inch wall aluminum tubing.
1 1/4 inch × 1 1/4 inch × 1/8 structural angle iron; or
1 inch ×.070 inch wall steel tubing; or
1.990 inch ×.058 inch wall aluminum tubing.
2. Specific guidelines and tables.
| Light duty up to 20 feet high | Light duty up to 60 feet high | Medium duty up to 60 feet high | Heavy duty up to 60 feet high | |
|---|---|---|---|---|
| Maximum intended load (lbs/ft 2 ) | 25 | 25 | 50 | 75 |
| Poles or uprights | 2 × 4 in | 4 × 4 in | 4 × 4 in | 4 × 6 in. |
| Maximum pole spacing (longitudinal) | 6 feet | 10 feet | 8 feet | 6 feet |
| Maximum pole spacing (transverse) | 5 feet | 5 feet | 5 feet | 5 feet |
| Runners | 1 × 4 in | 1 1 ⁄ 4 × 9 in | 2 × 10 in | 2 × 10 in. |
| Bearers and maximum spacing of bearers: | ||||
| 3 feet | 2 × 4 in | 2 × 4 in | 2 × 10 in. or 3 × 4 in | 2 × 10 in. or 3 × 5 in. |
| 5 feet | 2 × 6 in. or 3 × 4 in | 2 × 6 in. or 3 × 4 in. (rough) | 2 × 10 in. or 3 × 4 in | 2 × 10 in. or 3 × 5 in. |
| 6 feet | 2 × 10 in. or 3 × 4 in | 2 × 10 in. or 3 × 5 in. | ||
| 8 feet | 2 × 10 in. or 3 × 4 in | |||
| Planking | 1 1 ⁄ 4 × 9 in | 2 × 10 in | 2 × 10 in | 2 × 10 in. |
| Maximum vertical spacing of horizontal members | 7 feet | 9 feet | 7 feet | 6 ft. 6 in. |
| Bracing horizontal | 1 × 4 in | 1 × 4 in | 1 × 6 in. or 1 1 ⁄ 4 × 4 in | 2 × 4 in. |
| Bracing diagonal | 1 × 4 in | 1 × 4 in | 1 × 4 in | 2 × 4 in. |
| Tie-ins | 1 × 4 in | 1 × 4 in | 1 × 4 in | 1 × 4 in. |
| Note: All members except planking are used on edge. All wood bearers shall be reinforced with 3 ⁄ 16 × 2 inch steel strip, or the equivalent, secured to the lower edges for the entire length of the bearer. |
| Light duty up to 20 feet high | Light duty up to 60 feet high | Medium duty up to 60 feet high | Heavy duty up to 60 feet high | |
|---|---|---|---|---|
| Maximum intended load | 25 lbs/ft 2 | 25 lbs/ft 2 | 50 lbs/ft 2 | 75 lbs/ft 2 . |
| Poles or uprights | 2 × 4 in | 4 × 4 in | 4 × 4 in | 4 × 4 in. |
| Maximum pole spacing (longitudinal) | 6 feet | 10 feet | 8 feet | 6 feet. |
| Maximum (transverse) | 6 feet | 10 feet | 8 feet | 8 feet. |
| Runners | 1 1 ⁄ 4 × 4 in | 1 1 ⁄ 4 × 9 in | 2 × 10 in | 2 × 10 in. |
| Bearers and maximum spacing of bearers: | ||||
| 3 feet | 2 × 4 in | 2 × 4 in | 2 × 10 in | 2 × 10 in. (rough). |
| 6 feet | 2 × 6 in. or 3 × 4 in | 2 × 10 in. (rough) or 3 × 8 in | 2 × 10 in | 2 × 10 in. (rough). |
| 8 feet | 2 × 6 in. or 3 × 4 in | 2 × 10 in. (rough) or 3 × 8 in | 2 × 10 in | |
| 10 feet | 2 × 6 in. or 3 × 4 in | 2 × 10 in. (rough) or 3 × 3 in | ||
| Planking | 1 1 ⁄ 4 × 9 in | 2 × 10 in | 2 × 10 in | 2 × 10 in. |
| Maximum vertical spacing of horizontal members | 7 feet | 7 feet | 6 feet | 6 feet. |
| Bracing horizontal | 1 × 4 in | 1 × 4 in | 1 × 6 in. or 1 1 ⁄ 4 × 4 in | 2 × 4 in. |
| Bracing diagonal | 1 × 4 in | 1 × 4 in | 1 × 4 in | 2 × 4 in. |
| Tie-ins | 1 × 4 in | 1 × 4 in | 1 × 4 in | 1 × 4 in. |
| Note: All members except planking are used on edge. All wood bearers shall be reinforced with 3 ⁄ 16 × 2 inch steel strip, or the equivalent, secured to the lower edges for the entire length of the bearer. |
| Light duty | Medium duty | Heavy duty | |
|---|---|---|---|
| Maximum intended load | 25 lbs/ft 2 | 50 lbs/ft 2 | 75 lbs/ft 2 . |
| Posts, runners and braces | Nominal 2 in. (1.90 inches) OD steel tube or pipe | Nominal 2 in. (1.90 inches) OD steel tube or pipe | Nominal 2 in. (1.90 inches) OD steel tube or pipe. |
| Bearers | Nominal 2 in. (1.90 inches) | Nominal 2 in. (1.90 inches) | Nominal 2 1 ⁄ 2 in. (2.375 in.). |
| OD steel tube or pipe and a maximum post spacing of 4 ft. × 10 ft. | OD steel tube or pipe and a maximum post spacing of 4 ft. × 7 ft. or | OD steel tube or pipe and a maximum post spacing of 6 ft. × 6 ft. | |
| Nominal 2 1 ⁄ 2 in. (2.375 in.) | |||
| OD steel tube or pipe and a maximum post spacing of 6 ft. × 8 ft. * | |||
| Maximum runner spacing vertically | 6 ft. 6 in | 6 ft. 6 in | 6 ft. 6 in. |
| * Bearers shall be installed in the direction of the shorter dimension. | |||
| Note: Longitudinal diagonal bracing shall be installed at an angle of 45° (±5°). |
| Maximum number of additional planked levels | Maximum height of scaffold (in feet) | |||
|---|---|---|---|---|
| Light duty | Medium duty | Heavy duty | ||
| Number of Working Levels: | ||||
| 1 | 16 | 11 | 6 | 125 |
| 2 | 11 | 1 | 0 | 125 |
| 3 | 6 | 0 | 0 | 125 |
| 4 | 1 | 0 | 0 | 125 |
Because of their prefabricated nature, no additional guidelines or tables for these scaffolds are being adopted in this Appendix.
2
* The squares shall be set not more than 8 feet apart for light duty scaffolds and not more than 5 feet apart for medium duty scaffolds.
Maximum width: 5 ft.
Maximum height: 5 ft.
Gussets: 1 × 6 in.
Braces: 1 × 8 in.
Legs: 2 × 6 in.
Bearers (horizontal members): 2 × 6 in.
2
** Horses shall be spaced not more than 8 feet apart for light duty loads, and not more than 5 feet apart for medium duty loads.
2
Horizontal members or bearers:
Light duty: 2 × 4 in.
Medium duty: 3 × 4 in.
Legs: 2 × 4 in.
Longitudinal brace between legs: 1 × 6 in.
Gusset brace at top of legs: 1 × 8 in.
Half diagonal braces: 2 × 4 in.
2
Uprights: 2 × 4 in. or 2 × 6 in.
Bearers (two): 1 × 6 in.
Braces: 1 × 6 in.
Maximum length of bearers (unsupported): 3 ft. 6 in.
2
Uprights: 2 × 4 inch
Bearers: As designed.
Braces: As designed.
2
Uprights: 2 × 4 in or 2 × 6 in
Bearers: 2 × 6 in
Maximum scaffold width: 3 ft 6 in
Braces: 1 × 6 in
No specific guidelines or tables are given.
No specific guidelines or tables are given.
Wood poles shall not exceed 30 feet in height. Maximum intended load—500 lbs between poles; applied at the center of the span. Not more than two employees shall be on a pump jack scaffold at one time between any two supports. When 2 × 4's are spliced together to make a 4 × 4 inch wood pole, they shall be spliced with “10 penny” common nails no more than 12 inches center to center, staggered uniformly from the opposite outside edges.
Maximum intended load—25 lb/ft 2. However, not more than two employees shall occupy any platform at any one time. Maximum span between supports shall be 8 feet.
Not more than one employee shall occupy a window jack scaffold at any one time.
Crawling boards shall be not less than 10 inches wide and 1 inch thick, with cleats having a minimum 1 × 1 1/2 inch cross-sectional area. The cleats shall be equal in length to the width of the board and spaced at equal intervals not to exceed 24 inches.
Maximum intended load—250 lbs. Wood seats for boatswains' chairs shall be not less than 1 inch thick if made of non-laminated wood, or 5/8 inches thick if made of marine quality plywood.
The side stringer shall be of clear straight-grained spruce. The rungs shall be of straight-grained oak, ash, or hickory, at least 1 1/8 inches in diameter, with 7/8 inch tenons mortised into the side stringers at least 7/8 inch. The stringers shall be tied together with tie rods not less than 1/4 inch in diameter, passing through the stringers and riveted up tight against washers on both ends. The flooring strips shall be spaced not more than 5/8 inch apart, except at the side rails where the space may be 1 inch. Ladder-type platforms shall be constructed in accordance with the following table:
| Length of Platform | 12 feet | 14 & 16 feet | 18 & 20 feet. |
|---|---|---|---|
| Side stringers, minimum cross section (finished sizes): | |||
| At ends | 1 3 ⁄ 4 × 2 3 ⁄ 4 in | 1 3 ⁄ 4 × 2 3 ⁄ 4 in | 1 3 ⁄ 4 × 3 in. |
| At middle | 1 3 ⁄ 4 × 3 3 ⁄ 4 in | 1 3 ⁄ 4 × 3 3 ⁄ 4 in | 1 3 ⁄ 4 × 4 in. |
| Reinforcing strip (minimum) | A 1 ⁄ 8 × 7 ⁄ 8 inch steel reinforcing strip shall be attached to the side or underside, full length. | ||
| Rungs | Rungs shall be 1 1 ⁄ 8 inch minimum diameter with at least 7 ⁄ 8 inch in diameter tenons, and the maximum spacing shall be 12 inches to center. | ||
| Tie rods: | |||
| Number (minimum) | 3 | 4 | 4 |
| Diameter (minimum) | 1 ⁄ 4 inch | 1 ⁄ 4 inch | 1 ⁄ 4 inch |
| Flooring, minimum finished size | 1 ⁄ 2 × 2 3 ⁄ 4 in | 1 ⁄ 2 × 2 3 ⁄ 4 in | 1 ⁄ 2 × 2 3 ⁄ 4 in. |
| Length of Platform | 22 & 24 ft | 28 & 30 ft. |
|---|---|---|
| Side stringers, minimum cross section (finished sizes): | ||
| At ends | 1 3 ⁄ 4 × 3 in | 1 3 ⁄ 4 × 3 1 ⁄ 2 in. |
| At middle | 1 3 ⁄ 4 × 4 1 ⁄ 4 in | 1 3 ⁄ 4 × 5 in. |
| Reinforcing strip (minimum) | A 1 ⁄ 8 × 7 ⁄ 8 -inch steel reinforcing strip shall be attached to the side or underside, full length. | |
| Rungs | Rungs shall be 1 1 ⁄ 8 inch minimum diameter with at least 7 ⁄ 8 inch in diameter tenons, and the maximum spacing shall be 12 inches to center. Tie rods. | |
| Number (minimum) | 5 | 6. |
| Diameter (minimum) | 1 ⁄ 4 in | 1 ⁄ 4 in. |
| Flooring, minimum finished size | 1 ⁄ 2 × 2 3 ⁄ 4 in | 1 ⁄ 2 × 2 3 ⁄ 4 in. |
Plank-type platforms shall be composed of not less than nominal 2 × 8 inch unspliced planks, connected together on the underside with cleats at intervals not exceeding 4 feet, starting 6 inches from each end. A bar or other effective means shall be securely fastened to the platform at each end to prevent the platform from slipping off the hanger. The span between hangers for plank-type platforms shall not exceed 10 feet.
Beam platforms shall have side stringers of lumber not less than 2 × 6 inches set on edge. The span between hangers shall not exceed 12 feet when beam platforms are used. The flooring shall be supported on 2 × 6 inch cross beams, laid flat and set into the upper edge of the stringers with a snug fit, at intervals of not more than 4 feet, securely nailed to the cross beams. Floor-boards shall not be spaced more than 1/2 inch apart.
Maximum intended load—50 lb/ft 2. Each outrigger beam shall be at least a standard 7 inch, 15.3 pound steel I-beam, at least 15 feet long. Such beams shall not project more than 6 feet 6 inches beyond the bearing point. Where the overhang exceeds 6 feet 6 inches, outrigger beams shall be composed of stronger beams or multiple beams.
Bearers (use on edge): 2 × 10 in.
Maximum intended load: Maximum span
2
2
2
2
Beams: 4 × 6 in.
Maximum platform span: 8 ft.
Maximum beam span: 10 ft.
No additional guidelines or tables are being given for these scaffolds.
Stability test as described in the ANSI A92 series documents, as appropriate for the type of scaffold, can be used to establish stability for the purpose of § 1926.452(w)(6).
No additional guidelines or tables are being given for these scaffolds.
No specific guidelines or tables are given.
[44 FR 8577, Feb. 9, 1979, as amended at 77 FR 46950, Aug. 7, 2012]
Vehicle-Mounted Elevating and Rotating Aerial Devices
Manually Propelled Elevating Aerial Platforms
Boom Supported Elevating Work Platforms
Self-Propelled Elevating Work Platforms
Airline Ground Support Vehicle-Mounted Vertical Lift Devices
Vehicle-Mounted Bridge Inspection and Maintenance Devices
Mast-Climbing Work Platforms
This appendix D is provided to serve as a guide to assist employers when evaluating the training needs of employees erecting or dismantling supported scaffolds.
The Agency believes that employees erecting or dismantling scaffolds should be trained in the following topics:
General Overview of Scaffolding
• regulations and standards
• erection/dismantling planning
• PPE and proper procedures
• fall protection
• materials handling
• access
• working platforms
• foundations
• guys, ties and braces
Tubular Welded Frame Scaffolds
• specific regulations and standards
• components
• parts inspection
• erection/dismantling planning
• guys, ties and braces
• fall protection
• general safety
• access and platforms
• erection/dismantling procedures
• rolling scaffold assembly
• putlogs
Tube and Clamp Scaffolds
• specific regulations and standards
• components
• parts inspection
• erection/dismantling planning
• guys, ties and braces
• fall protection
• general safety
• access and platforms
• erection/dismantling procedures
• buttresses, cantilevers, & bridges
System Scaffolds
• specific regulations and standards
• components
• parts inspection
• erection/dismantling planning
• guys, ties and braces
• fall protection
• general safety
• access and platforms
• erection/dismantling procedures
• buttresses, cantilevers, & bridges
Scaffold erectors and dismantlers should all receive the general overview, and, in addition, specific training for the type of supported scaffold being erected or dismantled.
This appendix provides drawings of particular types of scaffolds and scaffold components, and graphic illustrations of bracing patterns and tie spacing patterns.
This appendix is intended to provide visual guidance to assist the user in complying with the requirements of subpart L, part 1926.
HOISTS MUST BE ELECTRONICALLY ISOLATED FROM SCAFFOLD
[61 FR 46122, Aug. 30, 1996; 61 FR 59832, Nov. 25, 1996; 85 FR 8736, Feb. 18, 2020]
Anchorage means a secure point of attachment for lifelines, lanyards or deceleration devices.
Body belt (safety belt) means a strap with means both for securing it about the waist and for attaching it to a lanyard, lifeline, or deceleration device.
Body harness means straps which may be secured about the employee in a manner that will distribute the fall arrest forces over at least the thighs, pelvis, waist, chest and shoulders with means for attaching it to other components of a personal fall arrest system.
Buckle means any device for holding the body belt or body harness closed around the employee's body.
Connector means a device which is used to couple (connect) parts of the personal fall arrest system and positioning device systems together. It may be an independent component of the system, such as a carabiner, or it may be an integral component of part of the system (such as a buckle or dee-ring sewn into a body belt or body harness, or a snap-hook spliced or sewn to a lanyard or self-retracting lanyard).
Controlled access zone (CAZ) means an area in which certain work (e.g., overhand bricklaying) may take place without the use of guardrail systems, personal fall arrest systems, or safety net systems and access to the zone is controlled.
Dangerous equipment means equipment (such as pickling or galvanizing tanks, degreasing units, machinery, electrical equipment, and other units) which, as a result of form or function, may be hazardous to employees who fall onto or into such equipment.
Deceleration device means any mechanism, such as a rope grab, rip-stitch lanyard, specially-woven lanyard, tearing or deforming lanyards, automatic self-retracting lifelines/lanyards, etc., which serves to dissipate a substantial amount of energy during a fall arrest, or otherwise limit the energy imposed on an employee during fall arrest.
Deceleration distance means the additional vertical distance a falling employee travels, excluding lifeline elongation and free fall distance, before stopping, from the point at which the deceleration device begins to operate. It is measured as the distance between the location of an employee's body belt or body harness attachment point at the moment of activation (at the onset of fall arrest forces) of the deceleration device during a fall, and the location of that attachment point after the employee comes to a full stop.
Equivalent means alternative designs, materials, or methods to protect against a hazard which the employer can demonstrate will provide an equal or greater degree of safety for employees than the methods, materials or designs specified in the standard.
Failure means load refusal, breakage, or separation of component parts. Load refusal is the point where the ultimate strength is exceeded.
Free fall means the act of falling before a personal fall arrest system begins to apply force to arrest the fall.
Free fall distance means the vertical displacement of the fall arrest attachment point on the employee's body belt or body harness between onset of the fall and just before the system begins to apply force to arrest the fall. This distance excludes deceleration distance, and lifeline/lanyard elongation, but includes any deceleration device slide distance or self-retracting lifeline/lanyard extension before they operate and fall arrest forces occur.
Guardrail system means a barrier erected to prevent employees from falling to lower levels.
Hole means a gap or void 2 inches (5.1 cm) or more in its least dimension, in a floor, roof, or other walking/working surface.
Infeasible means that it is impossible to perform the construction work using a conventional fall protection system (i.e., guardrail system, safety net system, or personal fall arrest system) or that it is technologically impossible to use any one of these systems to provide fall protection.
Lanyard means a flexible line of rope, wire rope, or strap which generally has a connector at each end for connecting the body belt or body harness to a deceleration device, lifeline, or anchorage.
Leading edge means the edge of a floor, roof, or formwork for a floor or other walking/working surface (such as the deck) which changes location as additional floor, roof, decking, or formwork sections are placed, formed, or constructed. A leading edge is considered to be an “unprotected side and edge” during periods when it is not actively and continuously under construction.
Lifeline means a component consisting of a flexible line for connection to an anchorage at one end to hang vertically (vertical lifeline), or for connection to anchorages at both ends to stretch horizontally (horizontal lifeline), and which serves as a means for connecting other components of a personal fall arrest system to the anchorage.
Low-slope roof means a roof having a slope less than or equal to 4 in 12 (vertical to horizontal).
Lower levels means those areas or surfaces to which an employee can fall. Such areas or surfaces include, but are not limited to, ground levels, floors, platforms, ramps, runways, excavations, pits, tanks, material, water, equipment, structures, or portions thereof.
Mechanical equipment means all motor or human propelled wheeled equipment used for roofing work, except wheelbarrows and mopcarts.
Opening means a gap or void 30 inches (76 cm) or more high and 18 inches (48 cm) or more wide, in a wall or partition, through which employees can fall to a lower level.
Overhand bricklaying and related work means the process of laying bricks and masonry units such that the surface of the wall to be jointed is on the opposite side of the wall from the mason, requiring the mason to lean over the wall to complete the work. Related work includes mason tending and electrical installation incorporated into the brick wall during the overhand bricklaying process.
Personal fall arrest system means a system used to arrest an employee in a fall from a working level. It consists of an anchorage, connectors, a body belt or body harness and may include a lanyard, deceleration device, lifeline, or suitable combinations of these. As of January 1, 1998, the use of a body belt for fall arrest is prohibited.
Positioning device system means a body belt or body harness system rigged to allow an employee to be supported on an elevated vertical surface, such as a wall, and work with both hands free while leaning.
Rope grab means a deceleration device which travels on a lifeline and automatically, by friction, engages the lifeline and locks so as to arrest the fall of an employee. A rope grab usually employs the principle of inertial locking, cam/level locking, or both.
Roof means the exterior surface on the top of a building. This does not include floors or formwork which, because a building has not been completed, temporarily become the top surface of a building.
Roofing work means the hoisting, storage, application, and removal of roofing materials and equipment, including related insulation, sheet metal, and vapor barrier work, but not including the construction of the roof deck.
Safety-monitoring system means a safety system in which a competent person is responsible for recognizing and warning employees of fall hazards.
Self-retracting lifeline/lanyard means a deceleration device containing a drum-wound line which can be slowly extracted from, or retracted onto, the drum under slight tension during normal employee movement, and which, after onset of a fall, automatically locks the drum and arrests the fall.
Snaphook means a connector comprised of a hook-shaped member with a normally closed keeper, or similar arrangement, which may be opened to permit the hook to receive an object and, when released, automatically closes to retain the object. Snaphooks are generally one of two types:
Steep roof means a roof having a slope greater than 4 in 12 (vertical to horizontal).
Toeboard means a low protective barrier that will prevent the fall of materials and equipment to lower levels and provide protection from falls for personnel.
Unprotected sides and edges means any side or edge (except at entrances to points of access) of a walking/working surface, e.g., floor, roof, ramp, or runway where there is no wall or guardrail system at least 39 inches (1.0 m) high.
Walking/working surface means any surface, whether horizontal or vertical on which an employee walks or works, including, but not limited to, floors, roofs, ramps, bridges, runways, formwork and concrete reinforcing steel but not including ladders, vehicles, or trailers, on which employees must be located in order to perform their job duties.
Warning line system means a barrier erected on a roof to warn employees that they are approaching an unprotected roof side or edge, and which designates an area in which roofing work may take place without the use of guardrail, body belt, or safety net systems to protect employees in the area.
Work area means that portion of a walking/working surface where job duties are being performed.
[59 FR 40730, Aug. 9, 1994, as amended at 60 FR 39255, Aug. 2, 1995; 66 FR 5265, Jan. 18, 2001; 75 FR 48133, Aug. 9, 2010; 79 FR 20696, Apr. 11, 2014]
Each employee on a walking/working surface (horizontal and vertical surface) with an unprotected side or edge which is 6 feet (1.8 m) or more above a lower level shall be protected from falling by the use of guardrail systems, safety net systems, or personal fall arrest systems.
Each employee in a hoist area shall be protected from falling 6 feet (1.8 m) or more to lower levels by guardrail systems or personal fall arrest systems. If guardrail systems, [or chain, gate, or guardrail] or portions thereof, are removed to facilitate the hoisting operation (e.g., during landing of materials), and an employee must lean through the access opening or out over the edge of the access opening (to receive or guide equipment and materials, for example), that employee shall be protected from fall hazards by a personal fall arrest system.
Each employee on the face of formwork or reinforcing steel shall be protected from falling 6 feet (1.8 m) or more to lower levels by personal fall arrest systems, safety net systems, or positioning device systems.
Except as otherwise provided in paragraph (b) of this section, each employee engaged in roofing activities on low-slope roofs, with unprotected sides and edges 6 feet (1.8 m) or more above lower levels shall be protected from falling by guardrail systems, safety net systems, personal fall arrest systems, or a combination of warning line system and guardrail system, warning line system and safety net system, or warning line system and personal fall arrest system, or warning line system and safety monitoring system. Or, on roofs 50-feet (15.25 m) or less in width (see appendix A to subpart M of this part), the use of a safety monitoring system alone [i.e. without the warning line system] is permitted.
Each employee on a steep roof with unprotected sides and edges 6 feet (1.8 m) or more above lower levels shall be protected from falling by guardrail systems with toeboards, safety net systems, or personal fall arrest systems.
Each employee engaged in the erection of precast concrete members (including, but not limited to the erection of wall panels, columns, beams, and floor and roof “tees”) and related operations such as grouting of precast concrete members, who is 6 feet (1.8 m) or more above lower levels shall be protected from falling by guardrail systems, safety net systems, or personal fall arrest systems, unless another provision in paragraph (b) of this section provides for an alternative fall protection measure. Exception: When the employer can demonstrate that it is infeasible or creates a greater hazard to use these systems, the employer shall develop and implement a fall protection plan which meets the requirements of paragraph (k) of § 1926.502.
Each employee engaged in residential construction activities 6 feet (1.8 m) or more above lower levels shall be protected by guardrail systems, safety net system, or personal fall arrest system unless another provision in paragraph (b) of this section provides for an alternative fall protection measure. Exception: When the employer can demonstrate that it is infeasible or creates a greater hazard to use these systems, the employer shall develop and implement a fall protection plan which meets the requirements of paragraph (k) of § 1926.502.
Each employee working on, at, above, or near wall openings (including those with chutes attached) where the outside bottom edge of the wall opening is 6 feet (1.8 m) or more above lower levels and the inside bottom edge of the wall opening is less than 39 inches (1.0 m) above the walking/working surface, shall be protected from falling by the use of a guardrail system, a safety net system, or a personal fall arrest system.
Except as provided in § 1926.500(a)(2) or in § 1926.501 (b)(1) through (b)(14), each employee on a walking/working surface 6 feet (1.8 m) or more above lower levels shall be protected from falling by a guardrail system, safety net system, or personal fall arrest system.
When an employee is exposed to falling objects, the employer shall have each employee wear a hard hat and shall implement one of the following measures:
Guardrail systems and their use shall comply with the following provisions:
Safety net systems and their use shall comply with the following provisions:
| Vertical distance from working level to horizontal plane of net | Minimum required horizontal distance of outer edge of net from the edge of the working surface |
|---|---|
| Up to 5 feet | 8 feet. |
| More than 5 feet up to 10 feet | 10 feet. |
| More than 10 feet | 13 feet. |
Personal fall arrest systems and their use shall comply with the provisions set forth below. Effective January 1, 1998, body belts are not acceptable as part of a personal fall arrest system. Note: The use of a body belt in a positioning device system is acceptable and is regulated under paragraph (e) of this section.
Positioning device systems and their use shall conform to the following provisions:
Warning line systems [See § 1926.501(b)(10)] and their use shall comply with the following provisions:
Controlled access zones [See §§ 1926.501(b)(9) and 1926.502(k)] and their use shall conform to the following provisions.
Safety monitoring systems [See §§ 1926.501(b)(10) and 1926.502(k)] and their use shall comply with the following provisions:
Covers for holes in floors, roofs, and other walking/working surfaces shall meet the following requirements:
Falling object protection shall comply with the following provisions:
This option is available only to employees engaged in leading edge work, precast concrete erection work, or residential construction work (See § 1926.501(b)(2), (b)(12), and (b)(13)) who can demonstrate that it is infeasible or it creates a greater hazard to use conventional fall protection equipment. The fall protection plan must conform to the following provisions.
The following training provisions supplement and clarify the requirements of § 1926.21 regarding the hazards addressed in subpart M of this part.
When the employer has reason to believe that any affected employee who has already been trained does not have the understanding and skill required by paragraph (a) of this section, the employer shall retrain each such employee. Circumstances where retraining is required include, but are not limited to, situations where:
Non-Mandatory Guidelines for Complying With § 1926.501(b)(10)
Such roofs may be broken down into subareas as shown in Example C. The process of dividing a roof area can produce many different configurations. Example C gives the general rule of using dividing lines of minimum length to minimize the size and number of the areas which are potentially less than 50 feet (15.25 m) wide. The intent is to minimize the number of roof areas where safety monitoring systems alone are sufficient protection.
[85 FR 8738, Feb. 18, 2020]
Non-Mandatory Guidelines for Complying with § 1926.502(b)
The standard requires guardrail systems and components to be designed and built to meet the requirements of § 1926.502 (b) (3), (4), and (5). This appendix serves as a non-mandatory guideline to assist employers in complying with these requirements. An employer may use these guidelines as a starting point for designing guardrail systems. However, the guidelines do not provide all the information necessary to build a complete system, and the employer is still responsible for designing and assembling these components in such a way that the completed system will meet the requirements of § 1926.502(b) (3), (4), and (5). Components for which no specific guidelines are given in this appendix (e.g., joints, base connections, components made with other materials, and components with other dimensions) must also be designed and constructed in such a way that the completed system meets the requirements of § 1926.502.
Wood components shall be minimum 1500 lb-ft/in 2 fiber (stress grade) construction grade lumber; the posts shall be at least 2-inch by 4-inch (5 cm × 10 cm) lumber spaced not more than 8 feet (2.4 m) apart on centers; the top rail shall be at least 2-inch by 4-inch (5 cm × 10 cm) lumber, the intermediate rail shall be at least 1-inch by 6-inch (2.5 cm × 15 cm) lumber. All lumber dimensions are nominal sizes as provided by the American Softwood Lumber Standards, dated January 1970.
posts, top rails, and intermediate railings shall be at least one and one-half inches nominal diameter (schedule 40 pipe) with posts spaced not more than 8 feet (2.4 m) apart on centers.
posts, top rails, and intermediate rails shall be at least 2-inch by 2-inch (5 cm × 10 cm) by 3/8 -inch (1.1 cm) angles, with posts spaced not more than 8 feet (2.4 m) apart on centers.
Non-Mandatory Guidelines for Complying With § 1926.502(d)
I. Test methods for personal fall arrest systems and positioning device systems —
This appendix serves as a non-mandatory guideline to assist employers comply with the requirements in § 1926.502(d). Paragraphs (b), (c), (d) and (e) of this appendix describe test procedures which may be used to determine compliance with the requirements in § 1926.502 (d)(16). As noted in appendix D of this subpart, the test methods listed here in appendix C can also be used to assist employers comply with the requirements in § 1926.502(e) (3) and (4) for positioning device systems.
The test consists of dropping the respective test weight once as specified in paragraph (d)(2)(i) or (d)(3)(i) of this section. A new, unused system should be used for each test.
The device should be evaluated or tested under the environmental conditions, (such as rain, ice, grease, dirt, type of lifeline, etc.), for which the device is designed.
The locking mechanisms of other self-activating-type deceleration devices designed for more than one arrest should lock each of 1,000 times as they would in normal service.
II. Additional non-mandatory guidelines for personal fall arrest systems. The following information constitutes additional guidelines for use in complying with requirements for a personal fall arrest system.
Before purchasing or putting into use a personal fall arrest system, an employer should obtain from the supplier information about the system based on its performance during testing so that the employer can know if the system meets this standard. Testing should be done using recognized test methods. This appendix contains test methods recognized for evaluating the performance of fall arrest systems. Not all systems may need to be individually tested; the performance of some systems may be based on data and calculations derived from testing of similar systems, provided that enough information is available to demonstrate similarity of function and design.
Ideally, a personal fall arrest system is designed, tested, and supplied as a complete system. However, it is common practice for lanyards, connectors, lifelines, deceleration devices, body belts and body harnesses to be interchanged since some components wear out before others. The employer and employee should realize that not all components are interchangeable. For instance, a lanyard should not be connected between a body belt (or harness) and a deceleration device of the self-retracting type since this can result in additional free fall for which the system was not designed. Any substitution or change to a personal fall arrest system should be fully evaluated or tested by a competent person to determine that it meets the standard, before the modified system is put in use.
Thorough employee training in the selection and use of personal fall arrest systems is imperative. Employees must be trained in the safe use of the system. This should include the following: application limits; proper anchoring and tie-off techniques; estimation of free fall distance, including determination of deceleration distance, and total fall distance to prevent striking a lower level; methods of use; and inspection and storage of the system. Careless or improper use of the equipment can result in serious injury or death. Employers and employees should become familiar with the material in this Appendix, as well as manufacturer's recommendations, before a system is used. Of uppermost importance is the reduction in strength caused by certain tie-offs (such as using knots, tying around sharp edges, etc.) and maximum permitted free fall distance. Also, to be stressed are the importance of inspections prior to use, the limitations of the equipment, and unique conditions at the worksite which may be important in determining the type of system to use.
Employers should obtain comprehensive instructions from the supplier as to the system's proper use and application, including, where applicable:
This information should be provided to employees during training.
As required by § 1926.502(d)(20), when personal fall arrest systems are used, the employer must assure that employees can be promptly rescued or can rescue themselves should a fall occur. The availability of rescue personnel, ladders or other rescue equipment should be evaluated. In some situations, equipment which allows employees to rescue themselves after the fall has been arrested may be desirable, such as devices which have descent capability.
As required by § 1926.502(d)(21), personal fall arrest systems must be regularly inspected. Any component with any significant defect, such as cuts, tears, abrasions, mold, or undue stretching; alterations or additions which might affect its efficiency; damage due to deterioration; contact with fire, acids, or other corrosives; distorted hooks or faulty hook springs; tongues unfitted to the shoulder of buckles; loose or damaged mountings; non-functioning parts; or wearing or internal deterioration in the ropes must be withdrawn from service immediately, and should be tagged or marked as unusable, or destroyed.
As required by the standard, each employee must have a separate lifeline [except employees engaged in constructing elevator shafts who are permitted to have two employees on one lifeline] when the lifeline is vertical. The reason for this is that in multiple tie-offs to a single lifeline, if one employee falls, the movement of the lifeline during the arrest of the fall may pull other employees' lanyards, causing them to fall as well.
The employer and employee should at all times be aware that a system's maximum arresting force is evaluated under normal use conditions established by the manufacturer, and in no case using a free fall distance in excess of 6 feet (1.8 m). A few extra feet of free fall can significantly increase the arresting force on the employee, possibly to the point of causing injury. Because of this, the free fall distance should be kept at a minimum, and, as required by the standard, in no case greater than 6 feet (1.8 m). To help assure this, the tie-off attachment point to the lifeline or anchor should be located at or above the connection point of the fall arrest equipment to belt or harness. (Since otherwise additional free fall distance is added to the length of the connecting means (i.e. lanyard)). Attaching to the working surface will often result in a free fall greater than 6 feet (1.8 m). For instance, if a 6 foot (1.8 m) lanyard is used, the total free fall distance will be the distance from the working level to the body belt (or harness) attachment point plus the 6 feet (1.8 m) of lanyard length. Another important consideration is that the arresting force which the fall system must withstand also goes up with greater distances of free fall, possibly exceeding the strength of the system.
Other factors involved in a proper tie-off are elongation and deceleration distance. During the arresting of a fall, a lanyard will experience a length of stretching or elongation, whereas activation of a deceleration device will result in a certain stopping distance. These distances should be available with the lanyard or device's instructions and must be added to the free fall distance to arrive at the total fall distance before an employee is fully stopped. The additional stopping distance may be very significant if the lanyard or deceleration device is attached near or at the end of a long lifeline, which may itself add considerable distance due to its own elongation. As required by the standard, sufficient distance to allow for all of these factors must also be maintained between the employee and obstructions below, to prevent an injury due to impact before the system fully arrests the fall. In addition, a minimum of 12 feet (3.7 m) of lifeline should be allowed below the securing point of a rope grab type deceleration device, and the end terminated to prevent the device from sliding off the lifeline. Alternatively, the lifeline should extend to the ground or the next working level below. These measures are suggested to prevent the worker from inadvertently moving past the end of the lifeline and having the rope grab become disengaged from the lifeline.
The location of the tie-off should also consider the hazard of obstructions in the potential fall path of the employee. Tie-offs which minimize the possibilities of exaggerated swinging should be considered. In addition, when a body belt is used, the employee's body will go through a horizontal position to a jack-knifed position during the arrest of all falls. Thus, obstructions which might interfere with this motion should be avoided or a severe injury could occur.
Because of the design of some personal fall arrest systems, additional considerations may be required for proper tie-off. For example, heavy deceleration devices of the self-retracting type should be secured overhead in order to avoid the weight of the device having to be supported by the employee. Also, if self- retracting equipment is connected to a horizontal lifeline, the sag in the lifeline should be minimized to prevent the device from sliding down the lifeline to a position which creates a swing hazard during fall arrest. In all cases, manufacturer's instructions should be followed.
Non-Mandatory Guidelines for Complying With § 1926.502(e)
I. Testing Methods For Positioning Device Systems. This appendix serves as a non-mandatory guideline to assist employers comply with the requirements for positioning device systems in § 1926.502(e). Paragraphs (b), (c), (d) and (e) of appendix C of subpart M relating to § 1926.502(d)—Personal Fall Arrest Systems—set forth test procedures which may be used, along with the procedures listed below, to determine compliance with the requirements for positioning device systems in § 1926.502(e) (3) and (4) of subpart M.
II. Inspection Considerations. As required in § 1926.502 (e)(5), positioning device systems must be regularly inspected. Any component with any significant defect, such as cuts, tears, abrasions, mold, or undue stretching; alterations or additions which might affect its efficiency; damage due to deterioration; contact with fire, acids, or other corrosives; distorted hooks or faulty hook springs; tongues unfitted to the shoulder of buckles; loose or damaged mountings; non-functioning parts; or wearing or internal deterioration in the ropes must be withdrawn from service immediately, and should be tagged or marked as unusable, or destroyed.
Non-Mandatory Guidelines for Complying With § 1926.502(k)
Employers engaged in leading edge work, precast concrete construction work and residential construction work who can demonstrate that it is infeasible or creates a greater hazard to use conventional fall protection systems must develop and follow a fall protection plan. Below are sample fall protection plans developed for precast concrete construction and residential work that could be tailored to be site specific for other precast concrete or residential jobsite. This sample plan can be modified to be used for other work involving leading edge work. The sample plan outlines the elements that must be addressed in any fall protection plan. The reasons outlined in this sample fall protection plan are for illustrative purposes only and are not necessarily a valid, acceptable rationale (unless the conditions at the job site are the same as those covered by these sample plans) for not using conventional fall protection systems for a particular precast concrete or residential construction worksite. However, the sample plans provide guidance to employers on the type of information that is required to be discussed in fall protection plans.
Sample Fall Protection Plans
Fall Protection Plan For Precast/Prestress Concrete Structures
This Fall Protection Plan is specific for the following project:
Location of Job
Erecting Company
Date Plan Prepared or Modified
Plan Prepared By
Plan Approved By
Plan Supervised By
The following Fall Protection Plan is a sample program prepared for the prevention of injuries associated with falls. A Fall Protection Plan must be developed and evaluated on a site by site basis. It is recommended that erectors discuss the written Fall Protection Plan with their OSHA Area Office prior to going on a jobsite.
I. Statement of Company Policy
This Fall Protection Plan addresses the use of other than conventional fall protection at a number of areas on the project, as well as identifying specific activities that require non-conventional means of fall protection. These areas include:
a. Connecting activity (point of erection).
b. Leading edge work.
c. Unprotected sides or edge.
d. Grouting.
This plan is designed to enable employers and employees to recognize the fall hazards on this job and to establish the procedures that are to be followed in order to prevent falls to lower levels or through holes and openings in walking/working surfaces. Each employee will be trained in these procedures and strictly adhere to them except when doing so would expose the employee to a greater hazard. If, in the employee's opinion, this is the case, the employee is to notify the foreman of the concern and the concern addressed before proceeding.
Safety policy and procedure on any one project cannot be administered, implemented, monitored and enforced by any one individual. The total objective of a safe, accident free work environment can only be accomplished by a dedicated, concerted effort by every individual involved with the project from management down to the last employee. Each employee must understand their value to the company; the costs of accidents, both monetary, physical, and emotional; the objective of the safety policy and procedures; the safety rules that apply to the safety policy and procedures; and what their individual role is in administering, implementing, monitoring, and compliance of their safety policy and procedures. This allows for a more personal approach to compliance through planning, training, understanding and cooperative effort, rather than by strict enforcement. If for any reason an unsafe act persists, strict enforcement will be implemented.
It is the responsibility of (name of competent person) to implement this Fall Protection Plan. (Name of Competent Person) is responsible for continual observational safety checks of their work operations and to enforce the safety policy and procedures. The foreman also is responsible to correct any unsafe acts or conditions immediately. It is the responsibility of the employee to understand and adhere to the procedures of this plan and to follow the instructions of the foreman. It is also the responsibility of the employee to bring to management's attention any unsafe or hazardous conditions or acts that may cause injury to either themselves or any other employees. Any changes to this Fall Protection Plan must be approved by (name of Qualified Person).
II. Fall Protection Systems To Be Used on This Project
Where conventional fall protection is infeasible or creates a greater hazard at the leading edge and during initial connecting activity, we plan to do this work using a safety monitoring system and expose only a minimum number of employees for the time necessary to actually accomplish the job. The maximum number of workers to be monitored by one safety monitor is six (6). We are designating the following trained employees as designated erectors and they are permitted to enter the controlled access zones and work without the use of conventional fall protection.
Safety monitor:
Designated erector:
Designated erector:
Designated erector:
Designated erector:
Designated erector:
Designated erector:
The safety monitor shall be identified by wearing an orange hard hat. The designated erectors will be identified by one of the following methods:
1. They will wear a blue colored arm band, or
2. They will wear a blue colored hard hat, or
3. They will wear a blue colored vest.
Only individuals with the appropriate experience, skills, and training will be authorized as designated erectors. All employees that will be working as designated erectors under the safety monitoring system shall have been trained and instructed in the following areas:
1. Recognition of the fall hazards in the work area (at the leading edge and when making initial connections—point of erection).
2. Avoidance of fall hazards using established work practices which have been made known to the employees.
3. Recognition of unsafe practices or working conditions that could lead to a fall, such as windy conditions.
4. The function, use, and operation of safety monitoring systems, guardrail systems, body belt/harness systems, control zones and other protection to be used.
5. The correct procedure for erecting, maintaining, disassembling and inspecting the system(s) to be used.
6. Knowledge of construction sequence or the erection plan.
A conference will take place prior to starting work involving all members of the erection crew, crane crew and supervisors of any other concerned contractors. This conference will be conducted by the precast concrete erection supervisor in charge of the project. During the pre-work conference, erection procedures and sequences pertinent to this job will be thoroughly discussed and safety practices to be used throughout the project will be specified. Further, all personnel will be informed that the controlled access zones are off limits to all personnel other than those designated erectors specifically trained to work in that area.
Safety Monitoring System
A safety monitoring system means a fall protection system in which a competent person is responsible for recognizing and warning employees of fall hazards. The duties of the safety monitor are to:
1. Warn by voice when approaching the open edge in an unsafe manner.
2. Warn by voice if there is a dangerous situation developing which cannot be seen by another person involved with product placement, such as a member getting out of control.
3. Make the designated erectors aware they are in a dangerous area.
4. Be competent in recognizing fall hazards.
5. Warn employees when they appear to be unaware of a fall hazard or are acting in an unsafe manner.
6. Be on the same walking/working surface as the monitored employees and within visual sighting distance of the monitored employees.
7. Be close enough to communicate orally with the employees.
8. Not allow other responsibilities to encumber monitoring. If the safety monitor becomes too encumbered with other responsibilities, the monitor shall (1) stop the erection process; and (2) turn over other responsibilities to a designated erector; or (3) turn over the safety monitoring function to another designated, competent person. The safety monitoring system shall not be used when the wind is strong enough to cause loads with large surface areas to swing out of radius, or result in loss of control of the load, or when weather conditions cause the walking-working surfaces to become icy or slippery.
Control Zone System
A controlled access zone means an area designated and clearly marked, in which leading edge work may take place without the use of guardrail, safety net or personal fall arrest systems to protect the employees in the area. Control zone systems shall comply with the following provisions:
1. When used to control access to areas where leading edge and other operations are taking place the controlled access zone shall be defined by a control line or by any other means that restricts access.
When control lines are used, they shall be erected not less than 6 feet (l.8 m) nor more than 60 feet (18 m) or half the length of the member being erected, whichever is less, from the leading edge.
2. The control line shall extend along the entire length of the unprotected or leading edge and shall be approximately parallel to the unprotected or leading edge.
3. The control line shall be connected on each side to a guardrail system or wall.
4. Control lines shall consist of ropes, wires, tapes, or equivalent materials, and supporting stanchions as follows:
5. Each line shall be flagged or otherwise clearly marked at not more than 6-foot (1.8 m) intervals with high- visibility material.
6. Each line shall be rigged and supported in such a way that its lowest point (including sag) is not less than 39 inches (1 m) from the walking/working surface and its highest point is not more than 45 inches (1.3 m) from the walking/working surface.
7. Each line shall have a minimum breaking strength of 200 pounds (.88 kN).
Holes
All openings greater than 12 in. × 12 in. will have perimeter guarding or covering. All predetermined holes will have the plywood covers made in the precasters' yard and shipped with the member to the jobsite. Prior to cutting holes on the job, proper protection for the hole must be provided to protect the workers. Perimeter guarding or covers will not be removed without the approval of the erection foreman.
Precast concrete column erection through the existing deck requires that many holes be provided through this deck. These are to be covered and protected. Except for the opening being currently used to erect a column, all opening protection is to be left undisturbed. The opening being uncovered to erect a column will become part of the point of erection and will be addressed as part of this Fall Protection Plan. This uncovering is to be done at the erection foreman's direction and will only occur immediately prior to “feeding” the column through the opening. Once the end of the column is through the slab opening, there will no longer exist a fall hazard at this location.
III. Implementation of Fall Protection Plan
The structure being erected is a multistory total precast concrete building consisting of columns, beams, wall panels and hollow core slabs and double tee floor and roof members.
The following is a list of the products and erection situations on this job:
Columns
For columns 10 ft to 36 ft long, employees disconnecting crane hooks from columns will work from a ladder and wear a body belt/harness with lanyard and be tied off when both hands are needed to disconnect. For tying off, a vertical lifeline will be connected to the lifting eye at the top of the column, prior to lifting, to be used with a manually operated or mobile rope grab. For columns too high for the use of a ladder, 36 ft and higher, an added cable will be used to reduce the height of the disconnecting point so that a ladder can be used. This cable will be left in place until a point in erection that it can be removed safely. In some cases, columns will be unhooked from the crane by using an erection tube or shackle with a pull pin which is released from the ground after the column is stabilized.
The column will be adequately connected and/or braced to safely support the weight of a ladder with an employee on it.
Inverted Tee Beams
Employees erecting inverted tee beams, at a height of 6 to 40 ft, will erect the beam, make initial connections, and final alignment from a ladder. If the employee needs to reach over the side of the beam to bar or make an adjustment to the alignment of the beam, they will mount the beam and be tied off to the lifting device in the beam after ensuring the load has been stabilized on its bearing. To disconnect the crane from the beam an employee will stand a ladder against the beam. Because the use of ladders is not practical at heights above 40 ft, beams will be initially placed with the use of tag lines and their final alignment made by a person on a manlift or similar employee positioning systems.
Spandrel Beams
Spandrel beams at the exterior of the building will be aligned as closely as possible with the use of tag lines with the final placement of the spandrel beam made from a ladder at the open end of the structure. A ladder will be used to make the initial connections and a ladder will be used to disconnect the crane. The other end of the beam will be placed by the designated erector from the double tee deck under the observation of the safety monitor.
The beams will be adequately connected and/or braced to safely support the weight of a ladder with an employee on it.
Floor and Roof Members
During installation of the precast concrete floor and/or roof members, the work deck continuously increases in area as more and more units are being erected and positioned. Thus, the unprotected floor/roof perimeter is constantly modified with the leading edge changing location as each member is installed. The fall protection for workers at the leading edge shall be assured by properly constructed and maintained control zone lines not more than 60 ft away from the leading edge supplemented by a safety monitoring system to ensure the safety of all designated erectors working within the area defined by the control zone lines.
The hollow core slabs erected on the masonry portion of the building will be erected and grouted using the safety monitoring system. Grout will be placed in the space between the end of the slab and face shell of the concrete masonry by dumping from a wheelbarrow. The grout in the keyways between the slabs will be dumped from a wheelbarrow and then spread with long handled tools, allowing the worker to stand erect facing toward the unprotected edge and back from any work deck edge.
Whenever possible, the designated erectors will approach the incoming member at the leading edge only after it is below waist height so that the member itself provides protection against falls.
Except for the situations described below, when the arriving floor or roof member is within 2 to 3 inches of its final position, the designated erectors can then proceed to their position of erection at each end of the member under the control of the safety monitor. Crane hooks will be unhooked from double tee members by designated erectors under the direction and supervision of the safety monitor.
Designated erectors, while waiting for the next floor or roof member, will be constantly under the control of the safety monitor for fall protection and are directed to stay a minimum of six (6) ft from the edge. In the event a designated erector must move from one end of a member, which has just been placed at the leading edge, they must first move away from the leading edge a minimum of six (6) ft and then progress to the other end while maintaining the minimum distance of six (6) ft at all times.
Erection of double tees, where conditions require bearing of one end into a closed pocket and the other end on a beam ledge, restricting the tee legs from going directly into the pockets, require special considerations. The tee legs that are to bear in the closed pocket must hang lower than those at the beam bearing. The double tee will be “two-lined” in order to elevate one end higher than the other to allow for the low end to be ducked into the closed pocket using the following procedure.
The double tee will be rigged with a standard four-way spreader off of the main load line. An additional choker will be attached to the married point of the two-legged spreader at the end of the tee that is to be elevated. The double tee will be hoisted with the main load line and swung into a position as close as possible to the tee's final bearing elevation. When the tee is in this position and stabilized, the whip line load block will be lowered to just above the tee deck. At this time, two erectors will walk out on the suspended tee deck at midspan of the tee member and pull the load block to the end of the tee to be elevated and attach the additional choker to the load block. The possibility of entanglement with the crane lines and other obstacles during this two lining process while raising and lowering the crane block on that second line could be hazardous to an encumbered employee. Therefore, the designated erectors will not tie off during any part of this process. While the designated erectors are on the double tee, the safety monitoring system will be used. After attaching the choker, the two erectors then step back on the previously erected tee deck and signal the crane operator to hoist the load with the whip line to the elevation that will allow for enough clearance to let the low end tee legs slide into the pockets when the main load line is lowered. The erector, who is handling the lowered end of the tee at the closed pocket bearing, will step out on the suspended tee. An erection bar will then be placed between the end of the tee leg and the inside face of the pocketed spandrel member. The tee is barred away from the pocketed member to reduce the friction and lateral force against the pocketed member. As the tee is being lowered, the other erector remains on the tee which was previously erected to handle the other end. At this point the tee is slowly lowered by the crane to a point where the tee legs can freely slide into the pockets. The erector working the lowered end of the tee must keep pressure on the bar between the tee and the face of the pocketed spandrel member to very gradually let the tee legs slide into the pocket to its proper bearing dimension. The tee is then slowly lowered into its final erected position.
The designated erector should be allowed onto the suspended double tee, otherwise there is no control over the horizontal movement of the double tee and this movement could knock the spandrel off of its bearing or the column out of plumb. The control necessary to prevent hitting the spandrel can only be done safely from the top of the double tee being erected.
Loadbearing Wall Panels: The erection of the loadbearing wall panels on the elevated decks requires the use of a safety monitor and a controlled access zone that is a minimum of 25 ft and a maximum of 1/2 the length of the wall panels away from the unprotected edge, so that designated erectors can move freely and unencumbered when receiving the panels. Bracing, if required for stability, will be installed by ladder. After the braces are secured, the crane will be disconnected from the wall by using a ladder. The wall to wall connections will also be performed from a ladder.
Non-Loadbearing Panels (Cladding): The locating of survey lines, panel layout and other installation prerequisites (prewelding, etc.) for non-loadbearing panels (cladding) will not commence until floor perimeter and floor openings have been protected. In some areas, it is necessary because of panel configuration to remove the perimeter protection as the cladding is being installed. Removal of perimeter protection will be performed on a bay to bay basis, just ahead of cladding erection to minimize temporarily unprotected floor edges. Those workers within 6 ft of the edge, receiving and positioning the cladding when the perimeter protection is removed shall be tied off.
Detailing
Employees exposed to falls of six (6) feet or more to lower levels, who are not actively engaged in leading edge work or connecting activity, such as welding, bolting, cutting, bracing, guying, patching, painting or other operations, and who are working less than six (6) ft from an unprotected edge will be tied off at all times or guardrails will be installed. Employees engaged in these activities but who are more than six (6) ft from an unprotected edge as defined by the control zone lines, do not require fall protection but a warning line or control lines must be erected to remind employees they are approaching an area where fall protection is required.
IV. Conventional Fall Protection Considered for the Point of Erection or Leading Edge Erection Operations
A. Personal Fall Arrest Systems
In this particular erection sequence and procedure, personal fall arrest systems requiring body belt/harness systems, lifelines and lanyards will not reduce possible hazards to workers and will create offsetting hazards during their usage at the leading edge of precast/prestressed concrete construction.
Leading edge erection and initial connections are conducted by employees who are specifically trained to do this type of work and are trained to recognize the fall hazards. The nature of such work normally exposes the employee to the fall hazard for a short period of time and installation of fall protection systems for a short duration is not feasible because it exposes the installers of the system to the same fall hazard, but for a longer period of time.
1. It is necessary that the employee be able to move freely without encumbrance in order to guide the sections of precast concrete into their final position without having lifelines attached which will restrict the employee's ability to move about at the point of erection.
2. A typical procedure requires 2 or more workers to maneuver around each other as a concrete member is positioned to fit into the structure. If they are each attached to a lifeline, part of their attention must be diverted from their main task of positioning a member weighing several tons to the task of avoiding entanglements of their lifelines or avoiding tripping over lanyards. Therefore, if these workers are attached to lanyards, more fall potential would result than from not using such a device.
In this specific erection sequence and procedure, retractable lifelines do not solve the problem of two workers becoming tangled. In fact, such a tangle could prevent the lifeline from retracting as the worker moved, thus potentially exposing the worker to a fall greater than 6 ft. Also, a worker crossing over the lifeline of another worker can create a hazard because the movement of one person can unbalance the other. In the event of a fall by one person there is a likelihood that the other person will be caused to fall as well. In addition, if contamination such as grout (during hollow core grouting) enters the retractable housing it can cause excessive wear and damage to the device and could clog the retracting mechanism as the lanyard is dragged across the deck. Obstructing the cable orifice can defeat the device's shock absorbing function, produce cable slack and damage, and adversely affect cable extraction and retraction.
3. Employees tied to a lifeline can be trapped and crushed by moving structural members if the employee becomes restrained by the lanyard or retractable lifeline and cannot get out of the path of the moving load.
The sudden movement of a precast concrete member being raised by a crane can be caused by a number of factors. When this happens, a connector may immediately have to move a considerable distance to avoid injury. If a tied off body belt/harness is being used, the connector could be trapped. Therefore, there is a greater risk of injury if the connector is tied to the structure for this specific erection sequence and procedure.
When necessary to move away from a retractable device, the worker cannot move at a rate greater than the device locking speed typically 3.5 to 4.5 ft/sec. When moving toward the device it is necessary to move at a rate which does not permit cable slack to build up. This slack may cause cable retraction acceleration and cause a worker to lose their balance by applying a higher than normal jerking force on the body when the cable suddenly becomes taut after building up momentum. This slack can also cause damage to the internal spring-loaded drum, uneven coiling of cable on the drum, and possible cable damage.
The factors causing sudden movements for this location include:
4. Anchorages or special attachment points could be cast into the precast concrete members if sufficient preplanning and consideration of erectors' position is done before the members are cast. Any hole or other attachment must be approved by the engineer who designed the member. It is possible that some design restrictions will not allow a member to be weakened by an additional hole; however, it is anticipated that such situations would be the exception, not the rule. Attachment points, other than on the deck surface, will require removal and/or patching. In order to remove and/or patch these points, requires the employee to be exposed to an additional fall hazard at an unprotected perimeter. The fact that attachment points could be available anywhere on the structure does not eliminate the hazards of using these points for tying off as discussed above. A logical point for tying off on double tees would be using the lifting loops, except that they must be cut off to eliminate a tripping hazard at an appropriate time.
5. Providing attachment at a point above the walking/working surface would also create fall exposures for employees installing their devices. Final positioning of a precast concrete member requires it to be moved in such a way that it must pass through the area that would be occupied by the lifeline and the lanyards attached to the point above. Resulting entanglements of lifelines and lanyards on a moving member could pull employees from the work surface. Also, the structure is being created and, in most cases, there is no structure above the members being placed.
6. The ANSI A10.14-1991 American National Standard for Construction and Demolition Operations—Requirements for Safety Belts, Harnesses, Lanyards and Lifelines for Construction and Demolition Use, states that the anchor point of a lanyard or deceleration device should, if possible, be located above the wearer's belt or harness attachment. ANSI A10.14 also states that a suitable anchorage point is one which is located as high as possible to prevent contact with an obstruction below should the worker fall. Most manufacturers also warn in the user's handbook that the safety block/retractable lifeline must be positioned above the D-ring (above the work space of the intended user) and OSHA recommends that fall arrest and restraint equipment be used in accordance with the manufacturer's instructions.
Attachment of a retractable device to a horizontal cable near floor level or using the inserts in the floor or roof members may result in increased free fall due to the dorsal D-ring of the full-body harness riding higher than the attachment point of the snaphook to the cable or insert (e.g., 6 foot tall worker with a dorsal D-ring at 5 feet above the floor or surface, reduces the working length to only one foot, by placing the anchorage five feet away from the fall hazard). In addition, impact loads may exceed maximum fall arrest forces (MAF) because the fall arrest D-ring would be 4 to 5 feet higher than the safety block/retractable lifeline anchored to the walking-working surface; and the potential for swing hazards is increased.
Manufacturers also require that workers not work at a level where the point of snaphook attachment to the body harness is above the device because this will increase the free fall distance and the deceleration distance and will cause higher forces on the body in the event of an accidental fall.
Manufacturers recommend an anchorage for the retractable lifeline which is immovably fixed in space and is independent of the user's support systems. A moveable anchorage is one which can be moved around (such as equipment or wheeled vehicles) or which can deflect substantially under shock loading (such as a horizontal cable or very flexible beam). In the case of a very flexible anchorage, a shock load applied to the anchorage during fall arrest can cause oscillation of the flexible anchorage such that the retractable brake mechanism may undergo one or more cycles of locking/unlocking/locking (ratchet effect) until the anchorage deflection is dampened. Therefore, use of a moveable anchorage involves critical engineering and safety factors and should only be considered after fixed anchorage has been determined to be not feasible.
Horizontal cables used as an anchorage present an additional hazard due to amplification of the horizontal component of maximum arrest force (of a fall) transmitted to the points where the horizontal cable is attached to the structure. This amplification is due to the angle of sag of a horizontal cable and is most severe for small angles of sag. For a cable sag angle of 2 degrees the horizontal force on the points of cable attachment can be amplified by a factor of 15.
It is also necessary to install the retractable device vertically overhead to minimize swing falls. If an object is in the worker's swing path (or that of the cable) hazardous situations exist: (1) due to the swing, horizontal speed of the user may be high enough to cause injury when an obstacle in the swing fall path is struck by either the user or the cable; (2) the total vertical fall distance of the user may be much greater than if the user had fallen only vertically without a swing fall path.
With retractable lines, overconfidence may cause the worker to engage in inappropriate behavior, such as approaching the perimeter of a floor or roof at a distance appreciably greater than the shortest distance between the anchorage point and the leading edge. Though the retractable lifeline may arrest a worker's fall before he or she has fallen a few feet, the lifeline may drag along the edge of the floor or beam and swing the worker like a pendulum until the line has moved to a position where the distance between the anchorage point and floor edge is the shortest distance between those two points. Accompanying this pendulum swing is a lowering of the worker, with the attendant danger that he or she may violently impact the floor or some obstruction below.
The risk of a cable breaking is increased if a lifeline is dragged sideways across the rough surface or edge of a concrete member at the same moment that the lifeline is being subjected to a maximum impact loading during a fall. The typical 3/16 in. cable in a retractable lifeline has a breaking strength of from 3000 to 3700 lbs.
7. The competent person, who can take into account the specialized operations being performed on this project, should determine when and where a designated erector cannot use a personal fall arrest system.
B. Safety Net Systems
The nature of this particular precast concrete erection worksite precludes the safe use of safety nets where point of erection or leading edge work must take place.
1. To install safety nets in the interior high bay of the single story portion of the building poses rigging attachment problems. Structural members do not exist to which supporting devices for nets can be attached in the area where protection is required. As the erection operation advances, the location of point of erection or leading edge work changes constantly as each member is attached to the structure. Due to this constant change it is not feasible to set net sections and build separate structures to support the nets.
2. The nature of the erection process for the precast concrete members is such that an installed net would protect workers as they position and secure only one structural member. After each member is stabilized the net would have to be moved to a new location (this could mean a move of 8 to 10 ft or the possibility of a move to a different level or area of the structure) to protect workers placing the next piece in the construction sequence. The result would be the installation and dismantling of safety nets repeatedly throughout the normal work day. As the time necessary to install a net, test, and remove it is significantly greater than the time necessary to position and secure a precast concrete member, the exposure time for the worker installing the safety net would be far longer than for the workers whom the net is intended to protect. The time exposure repeats itself each time the nets and supporting hardware must be moved laterally or upward to provide protection at the point of erection or leading edge.
3. Strict interpretation of § 1926.502(c) requires that operations shall not be undertaken until the net is in place and has been tested. With the point of erection constantly changing, the time necessary to install and test a safety net significantly exceeds the time necessary to position and secure the concrete member.
4. Use of safety nets on exposed perimeter wall openings and opensided floors, causes attachment points to be left in architectural concrete which must be patched and filled with matching material after the net supporting hardware is removed. In order to patch these openings, additional numbers of employees must be suspended by swing stages, boatswain chairs or other devices, thereby increasing the amount of fall exposure time to employees.
5. Installed safety nets pose an additional hazard at the perimeter of the erected structure where limited space is available in which members can be turned after being lifted from the ground by the crane. There would be a high probability that the member being lifted could become entangled in net hardware, cables, etc.
6. The use of safety nets where structural wall panels are being erected would prevent movement of panels to point of installation. To be effective, nets would necessarily have to provide protection across the area where structural supporting wall panels would be set and plumbed before roof units could be placed.
7. Use of a tower crane for the erection of the high rise portion of the structure poses a particular hazard in that the crane operator cannot see or judge the proximity of the load in relation to the structure or nets. If the signaler is looking through nets and supporting structural devices while giving instructions to the crane operator, it is not possible to judge precise relationships between the load and the structure itself or to nets and supporting structural devices. This could cause the load to become entangled in the net or hit the structure causing potential damage.
C. Guardrail Systems
On this particular worksite, guardrails, barricades, ropes, cables or other perimeter guarding devices or methods on the erection floor will pose problems to safe erection procedures. Typically, a floor or roof is erected by placing 4 to 10 ft wide structural members next to one another and welding or grouting them together. The perimeter of a floor and roof changes each time a new member is placed into position. It is unreasonable and virtually impossible to erect guardrails and toe boards at the ever changing leading edge of a floor or roof.
1. To position a member safely it is necessary to remove all obstructions extending above the floor level near the point of erection. Such a procedure allows workers to swing a new member across the erected surface as necessary to position it properly without worrying about knocking material off of this surface.
Hollow core slab erection on the masonry wall requires installation of the perimeter protection where the masonry wall has to be constructed. This means the guardrail is installed then subsequently removed to continue the masonry construction. The erector will be exposed to a fall hazard for a longer period of time while installing and removing perimeter protection than while erecting the slabs.
In hollow core work, as in other precast concrete erection, others are not typically on the work deck until the precast concrete erection is complete. The deck is not complete until the leveling, aligning, and grouting of the joints is done. It is normal practice to keep others off the deck until at least the next day after the installation is complete to allow the grout to harden.
2. There is no permanent boundary until all structural members have been placed in the floor or roof. At the leading edge, workers are operating at the temporary edge of the structure as they work to position the next member in the sequence. Compliance with the standard would require a guardrail and toe board be installed along this edge. However, the presence of such a device would prevent a new member from being swung over the erected surface low enough to allow workers to control it safely during the positioning process. Further, these employees would have to work through the guardrail to align the new member and connect it to the structure. The guardrail would not protect an employee who must lean through it to do the necessary work, rather it would hinder the employee to such a degree that a greater hazard is created than if the guardrail were absent.
3. Guardrail requirements pose a hazard at the leading edge of installed floor or roof sections by creating the possibility of employees being caught between guardrails and suspended loads. The lack of a clear work area in which to guide the suspended load into position for placement and welding of members into the existing structure creates still further hazards.
4. Where erection processes require precast concrete stairways or openings to be installed as an integral part of the overall erection process, it must also be recognized that guardrails or handrails must not project above the surface of the erection floor. Such guardrails should be terminated at the level of the erection floor to avoid placing hazardous obstacles in the path of a member being positioned.
V. Other Fall Protection Measures Considered for This Job
The following is a list and explanation of other fall protection measures available and an explanation of limitations for use on this particular jobsite. If during the course of erecting the building the employee sees an area that could be erected more safely by the use of these fall protection measures, the foreman should be notified.
A. Scaffolds are not used because:
1. The leading edge of the building is constantly changing and the scaffolding would have to be moved at very frequent intervals. Employees erecting and dismantling the scaffolding would be exposed to fall hazards for a greater length of time than they would by merely erecting the precast concrete member.
2. A scaffold tower could interfere with the safe swinging of a load by the crane.
3. Power lines, terrain and site do not allow for the safe use of scaffolding.
B. Vehicle mounted platforms are not used because:
1. A vehicle mounted platform will not reach areas on the deck that are erected over other levels.
2. The leading edge of the building is usually over a lower level of the building and this lower level will not support the weight of a vehicle mounted platform.
3. A vehicle mounted platform could interfere with the safe swinging of a load by the crane, either by the crane swinging the load over or into the equipment.
4. Power lines and surrounding site work do not allow for the safe use of a vehicle mounted platform.
C. Crane suspended personnel platforms are not used because:
1. A second crane close enough to suspend any employee in the working and erecting area could interfere with the safe swinging of a load by the crane hoisting the product to be erected.
2. Power lines and surrounding site work do not allow for the safe use of a second crane on the job.
VI. Enforcement
Constant awareness of and respect for fall hazards, and compliance with all safety rules are considered conditions of employment. The jobsite Superintendent, as well as individuals in the Safety and Personnel Department, reserve the right to issue disciplinary warnings to employees, up to and including termination, for failure to follow the guidelines of this program.
VII. Accident Investigations
All accidents that result in injury to workers, regardless of their nature, shall be investigated and reported. It is an integral part of any safety program that documentation take place as soon as possible so that the cause and means of prevention can be identified to prevent a reoccurrence.
In the event that an employee falls or there is some other related, serious incident occurring, this plan shall be reviewed to determine if additional practices, procedures, or training need to be implemented to prevent similar types of falls or incidents from occurring.
VIII. Changes to Plan
Any changes to the plan will be approved by (name of the qualified person). This plan shall be reviewed by a qualified person as the job progresses to determine if additional practices, procedures or training needs to be implemented by the competent person to improve or provide additional fall protection. Workers shall be notified and trained, if necessary, in the new procedures. A copy of this plan and all approved changes shall be maintained at the jobsite.
Sample Fall Protection Plan for Residential Construction
This Fall Protection Plan Is Specific For The Following Project:
Location of Job
Date Plan Prepared or Modified
Plan Prepared By
Plan Approved By
Plan Supervised By
The following Fall Protection Plan is a sample program prepared for the prevention of injuries associated with falls. A Fall Protection Plan must be developed and evaluated on a site by site basis. It is recommended that builders discuss the written Fall Protection Plan with their OSHA Area Office prior to going on a jobsite.
I. Statement of Company Policy
This Fall Protection Plan addresses the use of conventional fall protection at a number of areas on the project, as well as identifies specific activities that require non-conventional means of fall protection. During the construction of residential buildings under 48 feet in height, it is sometimes infeasible or it creates a greater hazard to use conventional fall protection systems at specific areas or for specific tasks. The areas or tasks may include, but are not limited to:
a. Setting and bracing of roof trusses and rafters;
b. Installation of floor sheathing and joists;
c. Roof sheathing operations; and
d. Erecting exterior walls.
In these cases, conventional fall protection systems may not be the safest choice for builders. This plan is designed to enable employers and employees to recognize the fall hazards associated with this job and to establish the safest procedures that are to be followed in order to prevent falls to lower levels or through holes and openings in walking/working surfaces.
Each employee will be trained in these procedures and will strictly adhere to them except when doing so would expose the employee to a greater hazard. If, in the employee's opinion, this is the case, the employee is to notify the competent person of their concern and have the concern addressed before proceeding.
It is the responsibility of (name of competent person) to implement this Fall Protection Plan. Continual observational safety checks of work operations and the enforcement of the safety policy and procedures shall be regularly enforced. The crew supervisor or foreman (insert name) is responsible for correcting any unsafe practices or conditions immediately.
It is the responsibility of the employer to ensure that all employees understand and adhere to the procedures of this plan and to follow the instructions of the crew supervisor. It is also the responsibility of the employee to bring to management's attention any unsafe or hazardous conditions or practices that may cause injury to either themselves or any other employees. Any changes to the Fall Protection Plan must be approved by (name of qualified person).
II. Fall Protection Systems To Be Used on This Job
Installation of roof trusses/rafters, exterior wall erection, roof sheathing, floor sheathing and joist/truss activities will be conducted by employees who are specifically trained to do this type of work and are trained to recognize the fall hazards. The nature of such work normally exposes the employee to the fall hazard for a short period of time. This Plan details how (Your company name here) will minimize these hazards.
Controlled Access Zones
When using the Plan to implement the fall protection options available, workers must be protected through limited access to high hazard locations. Before any non-conventional fall protection systems are used as part of the work plan, a controlled access zone (CAZ) shall be clearly defined by the competent person as an area where a recognized hazard exists. The demarcation of the CAZ shall be communicated by the competent person in a recognized manner, either through signs, wires, tapes, ropes or chains.
• All access to the CAZ must be restricted to authorized entrants;
• All workers who are permitted in the CAZ shall be listed in the appropriate sections of the Plan (or be visibly identifiable by the competent person) prior to implementation;
• The competent person shall ensure that all protective elements of the CAZ be implemented prior to the beginning of work.
Installation Procedures for Roof Truss and Rafter Erection
During the erection and bracing of roof trusses/rafters, conventional fall protection may present a greater hazard to workers. On this job, safety nets, guardrails and personal fall arrest systems will not provide adequate fall protection because the nets will cause the walls to collapse, while there are no suitable attachment or anchorage points for guardrails or personal fall arrest systems.
On this job, requiring workers to use a ladder for the entire installation process will cause a greater hazard because the worker must stand on the ladder with his back or side to the front of the ladder. While erecting the truss or rafter the worker will need both hands to maneuver the truss and therefore cannot hold onto the ladder. In addition, ladders cannot be adequately protected from movement while trusses are being maneuvered into place. Many workers may experience additional fatigue because of the increase in overhead work with heavy materials, which can also lead to a greater hazard.
Exterior scaffolds cannot be utilized on this job because the ground, after recent backfilling, cannot support the scaffolding. In most cases, the erection and dismantling of the scaffold would expose workers to a greater fall hazard than erection of the trusses/rafters.
On all walls eight feet or less, workers will install interior scaffolds along the interior wall below the location where the trusses/rafters will be erected. “Sawhorse” scaffolds constructed of 46 inch sawhorses and 2 × 10 planks will often allow workers to be elevated high enough to allow for the erection of trusses and rafters without working on the top plate of the wall.
In structures that have walls higher than eight feet and where the use of scaffolds and ladders would create a greater hazard, safe working procedures will be utilized when working on the top plate and will be monitored by the crew supervisor. During all stages of truss/rafter erection the stability of the trusses/rafters will be ensured at all times.
• Only the following trained workers will be allowed to work on the top plate during roof truss or rafter installation:
• Workers shall have no other duties to perform during truss/rafter erection procedures;
• All trusses/rafters will be adequately braced before any worker can use the truss/rafter as a support;
• Workers will remain on the top plate using the previously stabilized truss/rafter as a support while other trusses/rafters are being erected;
• Workers will leave the area of the secured trusses only when it is necessary to secure another truss/rafter;
• The first two trusses/rafters will be set from ladders leaning on side walls at points where the walls can support the weight of the ladder; and
• A worker will climb onto the interior top plate via a ladder to secure the peaks of the first two trusses/rafters being set.
The workers responsible for detaching trusses from cranes and/or securing trusses at the peaks traditionally are positioned at the peak of the trusses/rafters. There are also situations where workers securing rafters to ridge beams will be positioned on top of the ridge beam.
• Only the following trained workers will be allowed to work at the peak during roof truss or rafter installation:
• Once truss or rafter installation begins, workers not involved in that activity shall not stand or walk below or adjacent to the roof opening or exterior walls in any area where they could be struck by falling objects;
• Workers shall have no other duties than securing/bracing the trusses/ridge beam;
• Workers positioned at the peaks or in the webs of trusses or on top of the ridge beam shall work from a stable position, either by sitting on a “ridge seat” or other equivalent surface that provides additional stability or by positioning themselves in previously stabilized trusses/rafters and leaning into and reaching through the trusses/rafters;
• Workers shall not remain on or in the peak/ridge any longer than necessary to safely complete the task.
Roof Sheathing Operations
Workers typically install roof sheathing after all trusses/rafters and any permanent truss bracing is in place. Roof structures are unstable until some sheathing is installed, so workers installing roof sheathing cannot be protected from fall hazards by conventional fall protection systems until it is determined that the roofing system can be used as an anchorage point. At that point, employees shall be protected by a personal fall arrest system.
Trusses/rafters are subject to collapse if a worker falls while attached to a single truss with a belt/harness. Nets could also cause collapse, and there is no place to attach guardrails.
All workers will ensure that they have secure footing before they attempt to walk on the sheathing, including cleaning shoes/boots of mud or other slip hazards.
To minimize the time workers must be exposed to a fall hazard, materials will be staged to allow for the quickest installation of sheathing.
• Once roof sheathing installation begins, workers not involved in that activity shall not stand or walk below or adjacent to the roof opening or exterior walls in any area where they could be struck by falling objects;
• The competent person shall determine the limits of this area, which shall be clearly communicated to workers prior to placement of the first piece of roof sheathing;
• The competent person may order work on the roof to be suspended for brief periods as necessary to allow other workers to pass through such areas when this would not create a greater hazard;
• Only qualified workers shall install roof sheathing;
• The bottom row of roof sheathing may be installed by workers standing in truss webs;
• After the bottom row of roof sheathing is installed, a slide guard extending the width of the roof shall be securely attached to the roof. Slide guards are to be constructed of no less than nominal 4” height capable of limiting the uncontrolled slide of workers. Workers should install the slide guard while standing in truss webs and leaning over the sheathing;
• Additional rows of roof sheathing may be installed by workers positioned on previously installed rows of sheathing. A slide guard can be used to assist workers in retaining their footing during successive sheathing operations; and
• Additional slide guards shall be securely attached to the roof at intervals not to exceed 13 feet as successive rows of sheathing are installed. For roofs with pitches in excess of 9-in-12, slide guards will be installed at four-foot intervals.
• When wet weather (rain, snow, or sleet) are present, roof sheathing operations shall be suspended unless safe footing can be assured for those workers installing sheathing.
• When strong winds (above 40 miles per hour) are present, roof sheathing operations are to be suspended unless wind breakers are erected.
Installation of Floor Joists and Sheathing
During the installation of floor sheathing/joists (leading edge construction), the following steps shall be taken to protect workers:
• Only the following trained workers will be allowed to install floor joists or sheathing:
• Materials for the operations shall be conveniently staged to allow for easy access to workers;
• The first floor joists or trusses will be rolled into position and secured either from the ground, ladders or sawhorse scaffolds;
• Each successive floor joist or truss will be rolled into place and secured from a platform created from a sheet of plywood laid over the previously secured floor joists or trusses;
• Except for the first row of sheathing which will be installed from ladders or the ground, workers shall work from the established deck; and
• Any workers not assisting in the leading edge construction while leading edges still exist (e.g. cutting the decking for the installers) shall not be permitted within six feet of the leading edge under construction.
Erection of Exterior Walls
During the construction and erection of exterior walls, employers shall take the following steps to protect workers:
• Only the following trained workers will be allowed to erect exterior walls:
• A painted line six feet from the perimeter will be clearly marked prior to any wall erection activities to warn of the approaching unprotected edge;
• Materials for operations shall be conveniently staged to minimize fall hazards; and
• Workers constructing exterior walls shall complete as much cutting of materials and other preparation as possible away from the edge of the deck.
III. Enforcement
Constant awareness of and respect for fall hazards, and compliance with all safety rules are considered conditions of employment. The crew supervisor or foreman, as well as individuals in the Safety and Personnel Department, reserve the right to issue disciplinary warnings to employees, up to and including termination, for failure to follow the guidelines of this program.
IV. Accident Investigations
All accidents that result in injury to workers, regardless of their nature, shall be investigated and reported. It is an integral part of any safety program that documentation take place as soon as possible so that the cause and means of prevention can be identified to prevent a reoccurrence.
In the event that an employee falls or there is some other related, serious incident occurring, this plan shall be reviewed to determine if additional practices, procedures, or training need to be implemented to prevent similar types of falls or incidents from occurring.
V. Changes to Plan
Any changes to the plan will be approved by (name of the qualified person). This plan shall be reviewed by a qualified person as the job progresses to determine if additional practices, procedures or training needs to be implemented by the competent person to improve or provide additional fall protection. Workers shall be notified and trained, if necessary, in the new procedures. A copy of this plan and all approved changes shall be maintained at the jobsite.
[59 FR 40730, Aug. 9, 1994]
Helicopter cranes shall be expected to comply with any applicable regulations of the Federal Aviation Administration.
Prior to each day's operation a briefing shall be conducted. This briefing shall set forth the plan of operation for the pilot and ground personnel.
Load shall be properly slung. Tag lines shall be of a length that will not permit their being drawn up into rotors. Pressed sleeve, swedged eyes, or equivalent means shall be used for all freely suspended loads to prevent hand splices from spinning open or cable clamps from loosening.
All electrically operated cargo hooks shall have the electrical activating device so designed and installed as to prevent inadvertent operation. In addition, these cargo hooks shall be equipped with an emergency mechanical control for releasing the load. The hooks shall be tested prior to each day's operation to determine that the release functions properly, both electrically and mechanically.
Every practical precaution shall be taken to provide for the protection of the employees from flying objects in the rotor downwash. All loose gear within 100 feet of the place of lifting the load, depositing the load, and all other areas susceptible to rotor downwash shall be secured or removed.
Good housekeeping shall be maintained in all helicopter loading and unloading areas.
The helicopter operator shall be responsible for size, weight, and manner in which loads are connected to the helicopter. If, for any reason, the helicopter operator believes the lift cannot be made safely, the lift shall not be made.
When employees are required to perform work under hovering craft, a safe means of access shall be provided for employees to reach the hoist line hook and engage or disengage cargo slings. Employees shall not perform work under hovering craft except when necessary to hook or unhook loads.
Static charge on the suspended load shall be dissipated with a grounding device before ground personnel touch the suspended load, or protective rubber gloves shall be worn by all ground personnel touching the suspended load.
The weight of an external load shall not exceed the manufacturer's rating.
Hoist wires or other gear, except for pulling lines or conductors that are allowed to “pay out” from a container or roll off a reel, shall not be attached to any fixed ground structure, or allowed to foul on any fixed structure.
When visibility is reduced by dust or other conditions, ground personnel shall exercise special caution to keep clear of main and stabilizing rotors. Precautions shall also be taken by the employer to eliminate as far as practical reduced visibility.
No unauthorized person shall be allowed to approach within 50 feet of the helicopter when the rotor blades are turning.
Whenever approaching or leaving a helicopter with blades rotating, all employees shall remain in full view of the pilot and keep in a crouched position. Employees shall avoid the area from the cockpit or cabin rearward unless authorized by the helicopter operator to work there.
Sufficient ground personnel shall be provided when required for safe helicopter loading and unloading operations.
There shall be constant reliable communication between the pilot, and a designated employee of the ground crew who acts as a signalman during the period of loading and unloading. This signalman shall be distinctly recognizable from other ground personnel.
Open fires shall not be permitted in an area that could result in such fires being spread by the rotor downwash.
| Rope speed in feet per minute | Minimum factor of safety |
|---|---|
| 50 | 7.60 |
| 75 | 7.75 |
| 100 | 7.95 |
| 125 | 8.10 |
| 150 | 8.25 |
| 175 | 8.40 |
| 200 | 8.60 |
| 225 | 8.75 |
| 250 | 8.90 |
| 300 | 9.20 |
| 350 | 9.50 |
| 400 | 9.75 |
| 450 | 10.00 |
| 500 | 10.25 |
| 550 | 10.45 |
| 600 | 10.70 |
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 52 FR 36382, Sept. 28, 1987; 85 FR 8743, Feb. 18, 2020]
[Reserved]
[44 FR 8577, Feb. 9, 1979, as amended at 75 FR 48134, Aug. 9, 2010]
[Reserved]
Derail and/or bumper blocks shall be provided on spur railroad tracks where a rolling car could contact other cars being worked, enter a building, work or traffic area.
[Reserved]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35183, June 30, 1993; 75 FR 48134, Aug. 9, 2010]
Motor vehicles as covered by this part are those vehicles that operate within an off-highway jobsite, not open to public traffic. The requirements of this section do not apply to equipment for which rules are prescribed in § 1926.602.
All earthmoving equipment mentioned in this § 1926.602(a) shall have a service braking system capable of stopping and holding the equipment fully loaded, as specified in Society of Automotive Engineers SAE-J237, Loader Dozer-1971, J236, Graders-1971, and J319b, Scrapers-1971. Brake systems for self-propelled rubber-tired off-highway equipment manufactured after January 1, 1972 shall meet the applicable minimum performance criteria set forth in the following Society of Automotive Engineers Recommended Practices:
| Self-Propelled Scrapers | SAE J319b-1971. |
|---|---|
| Self-Propelled Graders | SAE J236-1971. |
| Trucks and Wagons | SAE J166-1971. |
| Front End Loaders and Dozers | SAE J237-1971. |
Pneumatic-tired earth-moving haulage equipment (trucks, scrapers, tractors, and trailing units) whose maximum speed exceeds 15 miles per hour, shall be equipped with fenders on all wheels to meet the requirements of Society of Automotive Engineers SAE J321a-1970, Fenders for Pneumatic-Tired Earthmoving Haulage Equipment. An employer may, of course, at any time seek to show under § 1926.2, that the uncovered wheels present no hazard to personnel from flying materials.
See subpart W of this part for requirements for rollover protective structures and overhead protection.
The promulgation of standards for rollover protective structures for off-highway trucks is reserved pending further study and development.
Scissor points on all front-end loaders, which constitute a hazard to the operator during normal operation, shall be guarded.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35183, June 30, 1993; 63 FR 66274, Dec. 1, 1998]
Barges or floats supporting pile driving operations shall meet the applicable requirements of § 1926.605.
[Reserved]
Commercial diving operations shall be subject to subpart T of part 1910, §§ 1910.401-1910.441, of this chapter.
[39 FR 22801, June 24, 1974, as amended at 42 FR 37674, July 22, 1977]
This subpart applies to all open excavations made in the earth's surface. Excavations are defined to include trenches.
Accepted engineering practices means those requirements which are compatible with standards of practice required by a registered professional engineer.
Aluminum Hydraulic Shoring means a pre-engineered shoring system comprised of aluminum hydraulic cylinders (crossbraces) used in conjunction with vertical rails (uprights) or horizontal rails (walers). Such system is designed, specifically to support the sidewalls of an excavation and prevent cave-ins.
Bell-bottom pier hole means a type of shaft or footing excavation, the bottom of which is made larger than the cross section above to form a belled shape.
Benching (Benching system) means a method of protecting employees from cave-ins by excavating the sides of an excavation to form one or a series of horizontal levels or steps, usually with vertical or near-vertical surfaces between levels.
Cave-in means the separation of a mass of soil or rock material from the side of an excavation, or the loss of soil from under a trench shield or support system, and its sudden movement into the excavation, either by falling or sliding, in sufficient quantity so that it could entrap, bury, or otherwise injure and immobilize a person.
Competent person means one who is capable of identifying existing and predictable hazards in the surroundings, or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.
Cross braces mean the horizontal members of a shoring system installed perpendicular to the sides of the excavation, the ends of which bear against either uprights or wales.
Excavation means any man-made cut, cavity, trench, or depression in an earth surface, formed by earth removal.
Faces or sides means the vertical or inclined earth surfaces formed as a result of excavation work.
Failure means the breakage, displacement, or permanent deformation of a structural member or connection so as to reduce its structural integrity and its supportive capabilities.
Hazardous atmosphere means an atmosphere which by reason of being explosive, flammable, poisonous, corrosive, oxidizing, irritating, oxygen deficient, toxic, or otherwise harmful, may cause death, illness, or injury.
Kickout means the accidental release or failure of a cross brace.
Protective system means a method of protecting employees from cave-ins, from material that could fall or roll from an excavation face or into an excavation, or from the collapse of adjacent structures. Protective systems include support systems, sloping and benching systems, shield systems, and other systems that provide the necessary protection.
Ramp means an inclined walking or working surface that is used to gain access to one point from another, and is constructed from earth or from structural materials such as steel or wood.
Registered Professional Engineer means a person who is registered as a professional engineer in the state where the work is to be performed. However, a professional engineer, registered in any state is deemed to be a “registered professional engineer” within the meaning of this standard when approving designs for “manufactured protective systems” or “tabulated data” to be used in interstate commerce.
Sheeting means the members of a shoring system that retain the earth in position and in turn are supported by other members of the shoring system.
Shield (Shield system) means a structure that is able to withstand the forces imposed on it by a cave-in and thereby protect employees within the structure. Shields can be permanent structures or can be designed to be portable and moved along as work progresses. Additionally, shields can be either premanufactured or job-built in accordance with § 1926.652 (c)(3) or (c)(4). Shields used in trenches are usually referred to as “trench boxes” or “trench shields.”
Shoring (Shoring system) means a structure such as a metal hydraulic, mechanical or timber shoring system that supports the sides of an excavation and which is designed to prevent cave-ins.
Sides. See “Faces.”
Sloping (Sloping system) means a method of protecting employees from cave-ins by excavating to form sides of an excavation that are inclined away from the excavation so as to prevent cave-ins. The angle of incline required to prevent a cave-in varies with differences in such factors as the soil type, environmental conditions of exposure, and application of surcharge loads.
Stable rock means natural solid mineral material that can be excavated with vertical sides and will remain intact while exposed. Unstable rock is considered to be stable when the rock material on the side or sides of the excavation is secured against caving-in or movement by rock bolts or by another protective system that has been designed by a registered professional engineer.
Structural ramp means a ramp built of steel or wood, usually used for vehicle access. Ramps made of soil or rock are not considered structural ramps.
Support system means a structure such as underpinning, bracing, or shoring, which provides support to an adjacent structure, underground installation, or the sides of an excavation.
Tabulated data means tables and charts approved by a registered professional engineer and used to design and construct a protective system.
Trench (Trench excavation) means a narrow excavation (in relation to its length) made below the surface of the ground. In general, the depth is greater than the width, but the width of a trench (measured at the bottom) is not greater than 15 feet (4.6 m). If forms or other structures are installed or constructed in an excavation so as to reduce the dimension measured from the forms or structure to the side of the excavation to 15 feet (4.6 m) or less (measured at the bottom of the excavation), the excavation is also considered to be a trench.
Trench box. See “Shield.”
Trench shield. See “Shield.”
Uprights means the vertical members of a trench shoring system placed in contact with the earth and usually positioned so that individual members do not contact each other. Uprights placed so that individual members are closely spaced, in contact with or interconnected to each other, are often called “sheeting.”
Wales means horizontal members of a shoring system placed parallel to the excavation face whose sides bear against the vertical members of the shoring system or earth.
All surface encumbrances that are located so as to create a hazard to employees shall be removed or supported, as necessary, to safeguard employees.
Employees exposed to public vehicular traffic shall be provided with, and shall wear, warning vests or other suitable garments marked with or made of reflectorized or high-visibility material.
No employee shall be permitted underneath loads handled by lifting or digging equipment. Employees shall be required to stand away from any vehicle being loaded or unloaded to avoid being struck by any spillage or falling materials. Operators may remain in the cabs of vehicles being loaded or unloaded when the vehicles are equipped, in accordance with § 1926.601(b)(6), to provide adequate protection for the operator during loading and unloading operations.
When mobile equipment is operated adjacent to an excavation, or when such equipment is required to approach the edge of an excavation, and the operator does not have a clear and direct view of the edge of the excavation, a warning system shall be utilized such as barricades, hand or mechanical signals, or stop logs. If possible, the grade should be away from the excavation.
In addition to the requirements set forth in subparts D and E of this part (29 CFR 1926.50-1926.107) to prevent exposure to harmful levels of atmospheric contaminants and to assure acceptable atmospheric conditions, the following requirements shall apply:
[54 FR 45959, Oct. 31, 1989, as amended at 59 FR 40730, Aug. 9, 1994]
The slopes and configurations of sloping and benching systems shall be selected and constructed by the employer or his designee and shall be in accordance with the requirements of paragraph (b)(1); or, in the alternative, paragraph (b)(2); or, in the alternative, paragraph (b)(3), or, in the alternative, paragraph (b)(4), as follows:
Employees shall not be permitted to work on the faces of sloped or benched excavations at levels above other employees except when employees at the lower levels are adequately protected from the hazard of falling, rolling, or sliding material or equipment.
This appendix describes a method of classifying soil and rock deposits based on site and environmental conditions, and on the structure and composition of the earth deposits. The appendix contains definitions, sets forth requirements, and describes acceptable visual and manual tests for use in classifying soils.
This appendix applies when a sloping or benching system is designed in accordance with the requirements set forth in § 1926.652(b)(2) as a method of protection for employees from cave-ins. This appendix also applies when timber shoring for excavations is designed as a method of protection from cave-ins in accordance with appendix C to subpart P of part 1926, and when aluminum hydraulic shoring is designed in accordance with appendix D. This appendix also applies if other protective systems are designed and selected for use from data prepared in accordance with the requirements set forth in § 1926.652(c), and the use of the data is predicated on the use of the soil classification system set forth in this appendix.
The definitions and examples given below are based on, in whole or in part, the following: American Society for Testing Materials (ASTM) Standards D653-85 and D2488; The Unified Soils Classification System, the U.S. Department of Agriculture (USDA) Textural Classification Scheme; and The National Bureau of Standards Report BSS-121.
Cemented soil means a soil in which the particles are held together by a chemical agent, such as calcium carbonate, such that a hand-size sample cannot be crushed into powder or individual soil particles by finger pressure.
Cohesive soil means clay (fine grained soil), or soil with a high clay content, which has cohesive strength. Cohesive soil does not crumble, can be excavated with vertical sideslopes, and is plastic when moist. Cohesive soil is hard to break up when dry, and exhibits significant cohesion when submerged. Cohesive soils include clayey silt, sandy clay, silty clay, clay and organic clay.
Dry soil means soil that does not exhibit visible signs of moisture content.
Fissured means a soil material that has a tendency to break along definite planes of fracture with little resistance, or a material that exhibits open cracks, such as tension cracks, in an exposed surface.
Granular soil means gravel, sand, or silt, (coarse grained soil) with little or no clay content. Granular soil has no cohesive strength. Some moist granular soils exhibit apparent cohesion. Granular soil cannot be molded when moist and crumbles easily when dry.
Layered system means two or more distinctly different soil or rock types arranged in layers. Micaceous seams or weakened planes in rock or shale are considered layered.
Moist soil means a condition in which a soil looks and feels damp. Moist cohesive soil can easily be shaped into a ball and rolled into small diameter threads before crumbling. Moist granular soil that contains some cohesive material will exhibit signs of cohesion between particles.
Plastic means a property of a soil which allows the soil to be deformed or molded without cracking, or appreciable volume change.
Saturated soil means a soil in which the voids are filled with water. Saturation does not require flow. Saturation, or near saturation, is necessary for the proper use of instruments such as a pocket penetrometer or sheer vane.
Soil classification system means, for the purpose of this subpart, a method of categorizing soil and rock deposits in a hierarchy of Stable Rock, Type A, Type B, and Type C, in decreasing order of stability. The categories are determined based on an analysis of the properties and performance characteristics of the deposits and the environmental conditions of exposure.
Stable rock means natural solid mineral matter that can be excavated with vertical sides and remain intact while exposed.
Submerged soil means soil which is underwater or is free seeping.
Type A means cohesive soils with an unconfined compressive strength of 1.5 ton per square foot (tsf) (144 kPa) or greater. Examples of cohesive soils are: clay, silty clay, sandy clay, clay loam and, in some cases, silty clay loam and sandy clay loam. Cemented soils such as caliche and hardpan are also considered Type A. However, no soil is Type A if:
Type B means:
angular gravel (similar to crushed rock), silt, silt loam, sandy loam and, in some cases, silty clay loam and sandy clay loam.
Type C means:
Unconfined compressive strength means the load per unit area at which a soil will fail in compression. It can be determined by laboratory testing, or estimated in the field using a pocket penetrometer, by thumb penetration tests, and other methods.
Wet soil means soil that contains significantly more moisture than moist soil, but in such a range of values that cohesive material will slump or begin to flow when vibrated. Granular material that would exhibit cohesive properties when moist will lose those cohesive properties when wet.
Each soil and rock deposit shall be classified by a competent person as Stable Rock, Type A, Type B, or Type C in accordance with the definitions set forth in paragraph (b) of this appendix.
The classification of the deposits shall be made based on the results of at least one visual and at least one manual analysis. Such analyses shall be conducted by a competent person using tests described in paragraph (d) below, or in other recognized methods of soil classification and testing such as those adopted by the America Society for Testing Materials, or the U.S. Department of Agriculture textural classification system.
The visual and manual analyses, such as those noted as being acceptable in paragraph (d) of this appendix, shall be designed and conducted to provide sufficient quantitative and qualitative information as may be necessary to identify properly the properties, factors, and conditions affecting the classification of the deposits.
In a layered system, the system shall be classified in accordance with its weakest layer. However, each layer may be classified individually where a more stable layer lies under a less stable layer.
If, after classifying a deposit, the properties, factors, or conditions affecting its classification change in any way, the changes shall be evaluated by a competent person. The deposit shall be reclassified as necessary to reflect the changed circumstances.
Visual analysis is conducted to determine qualitative information regarding the excavation site in general, the soil adjacent to the excavation, the soil forming the sides of the open excavation, and the soil taken as samples from excavated material.
Soil that remains in clumps when excavated is cohesive. Soil that breaks up easily and does not stay in clumps is granular.
Manual analysis of soil samples is conducted to determine quantitative as well as qualitative properties of soil and to provide more information in order to classify soil properly.
Mold a moist or wet sample of soil into a ball and attempt to roll it into threads as thin as 1/8 -inch in diameter. Cohesive material can be successfully rolled into threads without crumbling. For example, if at least a two inch (50 mm) length of 1/8 -inch thread can be held on one end without tearing, the soil is cohesive.
If the soil is dry and crumbles on its own or with moderate pressure into individual grains or fine powder, it is granular (any combination of gravel, sand, or silt). If the soil is dry and falls into clumps which break up into smaller clumps, but the smaller clumps can only be broken up with difficulty, it may be clay in any combination with gravel, sand or silt. If the dry soil breaks into clumps which do not break up into small clumps and which can only be broken with difficulty, and there is no visual indication the soil is fissured, the soil may be considered unfissured.
The thumb penetration test can be used to estimate the unconfined compressive strength of cohesive soils. (This test is based on the thumb penetration test described in American Society for Testing and Materials (ASTM) Standard designation D2488—“Standard Recommended Practice for Description of Soils (Visual—Manual Procedure).”) Type A soils with an unconfined compressive strength of 1.5 tsf can be readily indented by the thumb; however, they can be penetrated by the thumb only with very great effort. Type C soils with an unconfined compressive strength of 0.5 tsf can be easily penetrated several inches by the thumb, and can be molded by light finger pressure. This test should be conducted on an undisturbed soil sample, such as a large clump of spoil, as soon as practicable after excavation to keep to a minimum the effects of exposure to drying influences. If the excavation is later exposed to wetting influences (rain, flooding), the classification of the soil must be changed accordingly.
Estimates of unconfined compressive strength of soils can also be obtained by use of a pocket penetrometer or by using a hand-operated shearvane.
The basic purpose of the drying test is to differentiate between cohesive material with fissures, unfissured cohesive material, and granular material. The procedure for the drying test involves drying a sample of soil that is approximately one inch thick (2.54 cm) and six inches (15.24 cm) in diameter until it is thoroughly dry:
[85 FR 8743, Feb. 18, 2020]
This appendix contains specifications for sloping and benching when used as methods of protecting employees working in excavations from cave-ins. The requirements of this appendix apply when the design of sloping and benching protective systems is to be performed in accordance with the requirements set forth in § 1926.652(b)(2).
Actual slope means the slope to which an excavation face is excavated.
Distress means that the soil is in a condition where a cave-in is imminent or is likely to occur. Distress is evidenced by such phenomena as the development of fissures in the face of or adjacent to an open excavation; the subsidence of the edge of an excavation; the slumping of material from the face or the bulging or heaving of material from the bottom of an excavation; the spalling of material from the face of an excavation; and ravelling, i.e., small amounts of material such as pebbles or little clumps of material suddenly separating from the face of an excavation and trickling or rolling down into the excavation.
Maximum allowable slope means the steepest incline of an excavation face that is acceptable for the most favorable site conditions as protection against cave-ins, and is expressed as the ratio of horizontal distance to vertical rise (H:V).
Short term exposure means a period of time less than or equal to 24 hours that an excavation is open.
Soil and rock deposits shall be classified in accordance with appendix A to subpart P of part 1926.
The maximum allowable slope for a soil or rock deposit shall be determined from Table B-1 of this appendix.
B-1.1 Excavations made in Type A soil.
1. All simple slope excavation 20 feet or less in depth shall have a maximum allowable slope of 3/4 :1.
Exception: Simple slope excavations which are open 24 hours or less (short term) and which are 12 feet or less in depth shall have a maximum allowable slope of 1/2 :1.
2. All benched excavations 20 feet or less in depth shall have a maximum allowable slope of 3/4 to 1 and maximum bench dimensions as follows:
3. All excavations 8 feet or less in depth which have unsupported vertically sided lower portions shall have a maximum vertical side of 3 1/2 feet.
All excavations more than 8 feet but not more than 12 feet in depth which unsupported vertically sided lower portions shall have a maximum allowable slope of 1:1 and a maximum vertical side of 3 1/2 feet.
All excavations 20 feet or less in depth which have vertically sided lower portions that are supported or shielded shall have a maximum allowable slope of 3/4 :1. The support or shield system must extend at least 18 inches above the top of the vertical side.
4. All other simple slope, compound slope, and vertically sided lower portion excavations shall be in accordance with the other options permitted under § 1926.652(b).
B-1.2 Excavations Made in Type B Soil
1. All simple slope excavations 20 feet or less in depth shall have a maximum allowable slope of 1:1.
2. All benched excavations 20 feet or less in depth shall have a maximum allowable slope of 1:1 and maximum bench dimensions as follows:
3. All excavations 20 feet or less in depth which have vertically sided lower portions shall be shielded or supported to a height at least 18 inches above the top of the vertical side. All such excavations shall have a maximum allowable slope of 1:1.
4. All other sloped excavations shall be in accordance with the other options permitted in § 1926.652(b).
B-1.3 Excavations Made in Type C Soil
1. All simple slope excavations 20 feet or less in depth shall have a maximum allowable slope of 1 1/2 :1.
2. All excavations 20 feet or less in depth which have vertically sided lower portions shall be shielded or supported to a height at least 18 inches above the top of the vertical side. All such excavations shall have a maximum allowable slope of 1 1/2 :1.
3. All other sloped excavations shall be in accordance with the other options permitted in § 1926.652(b).
B-1.4 Excavations Made in Layered Soils
1. All excavations 20 feet or less in depth made in layered soils shall have a maximum allowable slope for each layer as set forth below.
This appendix contains information that can be used timber shoring is provided as a method of protection from cave-ins in trenches that do not exceed 20 feet (6.1 m) in depth. This appendix must be used when design of timber shoring protective systems is to be performed in accordance with § 1926.652(c)(1). Other timber shoring configurations; other systems of support such as hydraulic and pneumatic systems; and other protective systems such as sloping, benching, shielding, and freezing systems must be designed in accordance with the requirements set forth in § 1926.652(b) and § 1926.652(c).
In order to use the data presented in this appendix, the soil type or types in which the excavation is made must first be determined using the soil classification method set forth in appendix A of subpart P of this part.
Information is presented in several forms as follows:
The members of the shoring system that are to be selected using this information are the cross braces, the uprights, and the wales, where wales are required. Minimum sizes of members are specified for use in different types of soil. There are six tables of information, two for each soil type. The soil type must first be determined in accordance with the soil classification system described in appendix A to subpart P of part 1926. Using the appropriate table, the selection of the size and spacing of the members is then made. The selection is based on the depth and width of the trench where the members are to be installed and, in most instances, the selection is also based on the horizontal spacing of the crossbraces. Instances where a choice of horizontal spacing of crossbracing is available, the horizontal spacing of the crossbraces must be chosen by the user before the size of any member can be determined. When the soil type, the width and depth of the trench, and the horizontal spacing of the crossbraces are known, the size and vertical spacing of the crossbraces, the size and vertical spacing of the wales, and the size and horizontal spacing of the uprights can be read from the appropriate table.
A trench dug in Type A soil is 13 feet deep and five feet wide.
From Table C-1.1, for acceptable arrangements of timber can be used.
Arrangement #B1
Space 4 × 4 crossbraces at six feet horizontally and four feet vertically.
Wales are not required.
Space 3 × 8 uprights at six feet horizontally. This arrangement is commonly called “skip shoring.”
Arrangement #B2
Space 4 × 6 crossbraces at eight feet horizontally and four feet vertically.
Space 8 × 8 wales at four feet vertically.
Space 2 × 6 uprights at four feet horizontally.
Arrangement #B3
Space 6 × 6 crossbraces at 10 feet horizontally and four feet vertically.
Space 8 × 10 wales at four feet vertically.
Space 2 × 6 uprights at five feet horizontally.
Arrangement #B4
Space 6 × 6 crossbraces at 12 feet horizontally and four feet vertically.
Space 10 × 10 wales at four feet vertically.
Spaces 3 × 8 uprights at six feet horizontally.
A trench dug in Type B soil in 13 feet deep and five feet wide. From Table C-1.2 three acceptable arrangements of members are listed.
Arrangement #B1
Space 6 × 6 crossbraces at six feet horizontally and five feet vertically.
Space 8 × 8 wales at five feet vertically.
Space 2 × 6 uprights at two feet horizontally.
Arrangement #B2
Space 6 × 8 crossbraces at eight feet horizontally and five feet vertically.
Space 10 × 10 wales at five feet vertically.
Space 2 × 6 uprights at two feet horizontally.
Arrangement #B3
Space 8 × 8 crossbraces at 10 feet horizontally and five feet vertically.
Space 10 × 12 wales at five feet vertically.
Space 2 × 6 uprights at two feet vertically.
A trench dug in Type C soil is 13 feet deep and five feet wide.
From Table C-1.3 two acceptable arrangements of members can be used.
Arrangement #B1
Space 8 × 8 crossbraces at six feet horizontally and five feet vertically.
Space 10 × 12 wales at five feet vertically.
Position 2 × 6 uprights as closely together as possible.
If water must be retained use special tongue and groove uprights to form tight sheeting.
Arrangement #B2
Space 8 × 10 crossbraces at eight feet horizontally and five feet vertically.
Space 12 × 12 wales at five feet vertically.
Position 2 × 6 uprights in a close sheeting configuration unless water pressure must be resisted. Tight sheeting must be used where water must be retained.
A trench dug in Type C soil is 20 feet deep and 11 feet wide. The size and spacing of members for the section of trench that is over 15 feet in depth is determined using Table C-1.3. Only one arrangement of members is provided.
Space 8 × 10 crossbraces at six feet horizontally and five feet vertically.
Space 12 × 12 wales at five feet vertically.
Use 3 × 6 tight sheeting.
Use of Tables C-2.1 through C-2.3 would follow the same procedures.
1. Member sizes at spacings other than indicated are to be determined as specified in § 1926.652(c), “Design of Protective Systems.”
2. When conditions are saturated or submerged use Tight Sheeting. Tight Sheeting refers to the use of specially-edged timber planks (e.g., tongue and groove) at least three inches thick, steel sheet piling, or similar construction that when driven or placed in position provide a tight wall to resist the lateral pressure of water and to prevent the loss of backfill material. Close Sheeting refers to the placement of planks side-by-side allowing as little space as possible between them.
3. All spacing indicated is measured center to center.
4. Wales to be installed with greater dimension horizontal.
5. If the vertical distance from the center of the lowest crossbrace to the bottom of the trench exceeds two and one-half feet, uprights shall be firmly embedded or a mudsill shall be used. Where uprights are embedded, the vertical distance from the center of the lowest crossbrace to the bottom of the trench shall not exceed 36 inches. When mudsills are used, the vertical distance shall not exceed 42 inches. Mudsills are wales that are installed at the toe of the trench side.
6. Trench jacks may be used in lieu of or in combination with timber crossbraces.
7. Placement cf crossbraces. When the vertical spacing of crossbraces is four feet, place the top crossbrace no more than two feet below the top of the trench. When the vertical spacing of crossbraces is five feet, place the top crossbrace no more than 2.5 feet below the top of the trench.
This appendix contains information that can be used when aluminum hydraulic shoring is provided as a method of protection against cave-ins in trenches that do not exceed 20 feet (6.1m) in depth. This appendix must be used when design of the aluminum hydraulic protective system cannot be performed in accordance with § 1926.652(c)(2).
In order to use data presented in this appendix, the soi1 type or types in which the excavation is made must first be determined using the soil classification method set forth in appendix A of subpart P of part 1926.
Information is presented in several forms as follows:
The members of the shoring system that are to be selected using this information are the hydraulic cylinders, and either the vertical shores or the horizontal wales. When a waler system is used the vertical timber sheeting to be used is also selected from these tables. The Tables D-1.1 and D-1.2 for vertical shores are used in Type A and B soils that do not require sheeting. Type B soils that may require sheeting, and Type C soils that always require sheeting are found in the horizontal wale Tables D-1.3 and D-1.4. The soil type must first be determined in accordance with the soil classification system described in appendix A to subpart P of part 1926. Using the appropriate table, the selection of the size and spacing of the members is made. The selection is based on the depth and width of the trench where the members are to be installed. In these tables the vertical spacing is held constant at four feet on center. The tables show the maximum horizontal spacing of cylinders allowed for each size of wale in the waler system tables, and in the vertical shore tables, the hydraulic cylinder horizontal spacing is the same as the vertical shore spacing.
A trench dug in Type A soil is 6 feet deep and 3 feet wide. From Table D-1.1: Find vertical shores and 2 inch diameter cylinders spaced 8 feet on center (o.c.) horizontally and 4 feet on center (o.c.) vertically. (See Figures 1 & 3 for typical installations.)
A trench is dug in Type B soil that does not require sheeting, 13 feet deep and 5 feet wide. From Table D-1.2: Find vertical shores and 2 inch diameter cylinders spaced 6.5 feet o.c. horizontally and 4 feet o.c. vertically. (See Figures 1 & 3 for typical installations.)
A trench is dug in previously disturbed Type B soil, with characteristics of a Type C soil, and will require sheeting. The trench is 18 feet deep and 12 feet wide. 8 foot horizontal spacing between cylinders is desired for working space. From Table D-1.3: Find horizontal wale with a section modulus of 14.0 spaced at 4 feet o.c. vertically and 3 inch diameter cylinder spaced at 9 feet maximum o.c. horizontally. 3 × 12 timber sheeting is required at close spacing vertically. (See Figure 4 for typical installation.)
A trench is dug in Type C soil, 9 feet deep and 4 feet wide. Horizontal cylinder spacing in excess of 6 feet is desired for working space. From Table D-1.4: Find horizontal wale with a section modulus of 7.0 and 2 inch diameter cylinders spaced at 6.5 feet o.c. horizontally. Or, find horizontal wale with a 14.0 section modulus and 3 inch diameter cylinder spaced at 10 feet o.c. horizontally. Both wales are spaced 4 feet o.c. vertically. 3 × 12 timber sheeting is required at close spacing vertically. (See Figure 4 for typical installation.)
This subpart sets forth requirements to protect all construction employees from the hazards associated with concrete and masonry construction operations performed in workplaces covered under 29 CFR part 1926. In addition to the requirements in subpart Q, other relevant provisions in parts 1910 and 1926 apply to concrete and masonry construction operations.
In addition to the definitions set forth in § 1926.32, the following definitions apply to this subpart.
[53 FR 22643, June 16, 1988, as amended at 55 FR 42328, Oct. 18, 1990]
No construction loads shall be placed on a concrete structure or portion of a concrete structure unless the employer determines, based on information received from a person who is qualified in structural design, that the structure or portion of the structure is capable of supporting the loads.
All protruding reinforcing steel, onto and into which employees could fall, shall be guarded to eliminate the hazard of impalement.
No employee shall be permitted to ride concrete buckets.
No employee shall be permitted to apply a cement, sand, and water mixture through a pneumatic hose unless the employee is wearing protective head and face equipment.
[53 FR 22643, June 16, 1988, as amended at 59 FR 40730, Aug. 9, 1994]
Concrete mixers with one cubic yard (.8 m 3 ) or larger loading skips shall be equipped with the following:
Powered and rotating type concrete troweling machines that are manually guided shall be equipped with a control switch that will automatically shut off the power whenever the hands of the operator are removed from the equipment handles.
Concrete buggy handles shall not extend beyond the wheels on either side of the buggy.
Sections of tremies and similar concrete conveyances shall be secured with wire rope (or equivalent materials) in addition to the regular couplings or connections.
Bull float handles, used where they might contact energized electrical conductors, shall be constructed of nonconductive material or insulated with a nonconductive sheath whose electrical and mechanical characteristics provide the equivalent protection of a handle constructed of nonconductive material.
Appendix to § 1926.703( a )(1)
General Requirements for Formwork
This appendix serves as a non-mandatory guideline to assist employers in complying with the formwork requirements in § 1926.703(a)(1). Formwork which has been designed, fabricated, erected, braced, supported and maintained in accordance with Sections 6 and 7 of the American National Standard for Construction and Demolition Operations—Concrete and Masonry Work, ANSI A10.9-1983, shall be deemed to be in compliance with the provision of § 1926.703(a)(1).
[53 FR 22643, June 16, 1988, as amended at 61 FR 5510, Feb. 13, 1996]
[53 FR 22643, June 16, 1988, as amended at 54 FR 41088, Oct. 5, 1989]
Appendix to § 1926.705—Lift-Slab Operations
In paragraph 1926.705(k), OSHA requires employees to be removed from the building/structure during jacking operations unless an independent registered professional engineer, other than the engineer who designed and planned the lifting operation, has determined that the building/structure has been sufficiently reinforced to insure the integrity of the building/structure. One method to comply with this provision is for the employer to ensure that continuous bottom steel is provided in every slab and in both directions through every wall or column head area. (Column head area means the distance between lines that are one and one half times the thickness of the slab or drop panel. These lines are located outside opposite faces of the outer edges of the shearhead sections—See Figure 1). The amount of bottom steel shall be established by assuming loss of support at a given lifting jack and then determining the steel necessary to carry, by catenary action over the span between surrounding supports, the slab service dead load plus any service dead and live loads likely to be acting on the slab during jacking. In addition, the surrounding supports must be capable of resisting any additional load transferred to them as a result of the loss of support at the lifting jack considered.
[55 FR 42328, Oct. 18, 1990]
The following non-mandatory references provide information which can be helpful in understanding and complying with the requirements contained in subpart Q.
• Accident Prevention Manual for Industrial Operations; Eighth Edition; National Safety Council.
• Building Code Requirements for Reinforced Concrete (ACI 318-83).
• Formwork for Concrete (ACI SP-4).
• Recommended Practice for Concrete Formwork (ACI 347-78).
• Safety Requirements for Concrete and Masonry Work (ANSI A10.9-1983).
• Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens (ASTM C39-86).
• Standard Test Method for Making and Curing Concrete Test Specimens in the Field (ASTM C31-85).
• Standard Test Method for Penetration Resistance of Hardened Concrete (ASTM C803-82).
• Standard Test Method for Compressive Strength of Concrete Cylinders Cast In-Place in Cylindrical Molds (ASTM C873-85).
• Standard Method for Developing Early Age Compressive Test Values and Projecting Later Age Strengths (ASTM C918-80).
• Recommended Practice for Inspection and Testing Agencies for Concrete, Steel and Bituminous Materials as Used in Construction (ASTM E329-77).
• Method of Making and Curing Concrete Test Specimens in the Laboratory (ASTM C192-88).
• Methods of Obtaining and Testing Drilled Cores and Sawed Beams of Concrete (ASTM C42-87).
• Methods of Securing, Preparing and Testing Specimens from Hardened Lightweight Insulating Concrete for Compressive Strength (ASTM C513-86).
• Test Method for Comprehensive Strength of Lightweight Insulating Concrete (ASTM C495-86).
• Method of Making, Accelerating Curing, and Testing of Concrete Compression Test Specimens (ASTM C684-81).
• Test Method for Compressive Strength of Concrete Using Portions of Beams Broken in Flexure (ASTM C116-68 (1980)).
Anchored bridging means that the steel joist bridging is connected to a bridging terminus point.
Bolted diagonal bridging means diagonal bridging that is bolted to a steel joist or joists.
Bridging clip means a device that is attached to the steel joist to allow the bolting of the bridging to the steel joist.
Bridging terminus point means a wall, a beam, tandem joists (with all bridging installed and a horizontal truss in the plane of the top chord) or other element at an end or intermediate point(s) of a line of bridging that provides an anchor point for the steel joist bridging.
Choker means a wire rope or synthetic fiber rigging assembly that is used to attach a load to a hoisting device.
Cold forming means the process of using press brakes, rolls, or other methods to shape steel into desired cross sections at room temperature.
Column means a load-carrying vertical member that is part of the primary skeletal framing system. Columns do not include posts.
Competent person (also defined in § 1926.32) means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.
Connector means an employee who, working with hoisting equipment, is placing and connecting structural members and/or components.
Constructibility means the ability to erect structural steel members in accordance with subpart R without having to alter the over-all structural design.
Construction load (for joist erection) means any load other than the weight of the employee(s), the joists and the bridging bundle.
Controlled Decking Zone (CDZ) means an area in which certain work (for example, initial installation and placement of metal decking) may take place without the use of guardrail systems, personal fall arrest systems, fall restraint systems, or safety net systems and where access to the zone is controlled.
Controlled load lowering means lowering a load by means of a mechanical hoist drum device that allows a hoisted load to be lowered with maximum control using the gear train or hydraulic components of the hoist mechanism. Controlled load lowering requires the use of the hoist drive motor, rather than the load hoist brake, to lower the load.
Controlling contractor means a prime contractor, general contractor, construction manager or any other legal entity which has the overall responsibility for the construction of the project—its planning, quality and completion.
Critical lift means a lift that (1) exceeds 75 percent of the rated capacity of the crane or derrick, or (2) requires the use of more than one crane or derrick.
Decking hole means a gap or void more than 2 inches (5.1 cm) in its least dimension and less than 12 inches (30.5 cm) in its greatest dimension in a floor, roof or other walking/working surface. Pre-engineered holes in cellular decking (for wires, cables, etc.) are not included in this definition.
Derrick floor means an elevated floor of a building or structure that has been designated to receive hoisted pieces of steel prior to final placement.
Double connection means an attachment method where the connection point is intended for two pieces of steel which share common bolts on either side of a central piece.
Double connection seat means a structural attachment that, during the installation of a double connection, supports the first member while the second member is connected.
Erection bridging means the bolted diagonal bridging that is required to be installed prior to releasing the hoisting cables from the steel joists.
Fall restraint system means a fall protection system that prevents the user from falling any distance. The system is comprised of either a body belt or body harness, along with an anchorage, connectors and other necessary equipment. The other components typically include a lanyard, and may also include a lifeline and other devices.
Final interior perimeter means the perimeter of a large permanent open space within a building such as an atrium or courtyard. This does not include openings for stairways, elevator shafts, etc.
Girt (in systems-engineered metal buildings) means a “Z” or “C” shaped member formed from sheet steel spanning between primary framing and supporting wall material.
Headache ball means a weighted hook that is used to attach loads to the hoist load line of the crane.
Hoisting equipment means commercially manufactured lifting equipment designed to lift and position a load of known weight to a location at some known elevation and horizontal distance from the equipment's center of rotation. “Hoisting equipment” includes but is not limited to cranes, derricks, tower cranes, barge-mounted derricks or cranes, gin poles and gantry hoist systems. A “come-a-long” (a mechanical device, usually consisting of a chain or cable attached at each end, that is used to facilitate movement of materials through leverage) is not considered “hoisting equipment.”
Leading edge means the unprotected side and edge of a floor, roof, or formwork for a floor or other walking/working surface (such as deck) which changes location as additional floor, roof, decking or formwork sections are placed, formed or constructed.
Metal decking means a commercially manufactured, structural grade, cold rolled metal panel formed into a series of parallel ribs; for this subpart, this includes metal floor and roof decks, standing seam metal roofs, other metal roof systems and other products such as bar gratings, checker plate, expanded metal panels, and similar products. After installation and proper fastening, these decking materials serve a combination of functions including, but not limited to: a structural element designed in combination with the structure to resist, distribute and transfer loads, stiffen the structure and provide a diaphragm action; a walking/working surface; a form for concrete slabs; a support for roofing systems; and a finished floor or roof.
Multiple lift rigging means a rigging assembly manufactured by wire rope rigging suppliers that facilitates the attachment of up to five independent loads to the hoist rigging of a crane.
Opening means a gap or void 12 inches (30.5 cm) or more in its least dimension in a floor, roof or other walking/working surface. For the purposes of this subpart, skylights and smoke domes that do not meet the strength requirements of § 1926.754(e)(3) shall be regarded as openings.
Permanent floor means a structurally completed floor at any level or elevation (including slab on grade).
Personal fall arrest system means a system used to arrest an employee in a fall from a working level. A personal fall arrest system consists of an anchorage, connectors, a body harness and may include a lanyard, deceleration device, lifeline, or suitable combination of these. The use of a body belt for fall arrest is prohibited.
Positioning device system means a body belt or body harness rigged to allow an employee to be supported on an elevated, vertical surface, such as a wall or column and work with both hands free while leaning.
Post means a structural member with a longitudinal axis that is essentially vertical, that: (1) weighs 300 pounds or less and is axially loaded (a load presses down on the top end), or (2) is not axially loaded, but is laterally restrained by the above member. Posts typically support stair landings, wall framing, mezzanines and other substructures.
Project structural engineer of record means the registered, licensed professional responsible for the design of structural steel framing and whose seal appears on the structural contract documents.
Purlin (in systems-engineered metal buildings) means a “Z” or “C” shaped member formed from sheet steel spanning between primary framing and supporting roof material.
Qualified person (also defined in § 1926.32) means one who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated the ability to solve or resolve problems relating to the subject matter, the work, or the project.
Safety deck attachment means an initial attachment that is used to secure an initially placed sheet of decking to keep proper alignment and bearing with structural support members.
Shear connector means headed steel studs, steel bars, steel lugs, and similar devices which are attached to a structural member for the purpose of achieving composite action with concrete.
Steel erection means the construction, alteration or repair of steel buildings, bridges and other structures, including the installation of metal decking and all planking used during the process of erection.
Steel joist means an open web, secondary load-carrying member of 144 feet (43.9 m) or less, designed by the manufacturer, used for the support of floors and roofs. This does not include structural steel trusses or cold-formed joists.
Steel joist girder means an open web, primary load-carrying member, designed by the manufacturer, used for the support of floors and roofs. This does not include structural steel trusses.
Steel truss means an open web member designed of structural steel components by the project structural engineer of record. For the purposes of this subpart, a steel truss is considered equivalent to a solid web structural member.
Structural steel means a steel member, or a member made of a substitute material (such as, but not limited to, fiberglass, aluminum or composite members). These members include, but are not limited to, steel joists, joist girders, purlins, columns, beams, trusses, splices, seats, metal decking, girts, and all bridging, and cold formed metal framing which is integrated with the structural steel framing of a building.
Systems-engineered metal building means a metal, field-assembled building system consisting of framing, roof and wall coverings. Typically, many of these components are cold-formed shapes. These individual parts are fabricated in one or more manufacturing facilities and shipped to the job site for assembly into the final structure. The engineering design of the system is normally the responsibility of the systems-engineered metal building manufacturer.
Tank means a container for holding gases, liquids or solids.
Unprotected sides and edges means any side or edge (except at entrances to points of access) of a walking/working surface, for example a, floor, roof, ramp or runway, where there is no wall or guardrail system at least 39 inches (1.0 m) high.
Before authorizing the commencement of steel erection, the controlling contractor shall ensure that the steel erector is provided with the following written notifications:
A steel erection contractor shall not erect steel unless it has received written notification that the concrete in the footings, piers and walls or the mortar in the masonry piers and walls has attained, on the basis of an appropriate ASTM standard test method of field-cured samples, either 75 percent of the intended minimum compressive design strength or sufficient strength to support the loads imposed during steel erection.
The controlling contractor shall ensure that the following is provided and maintained:
All hoisting operations in steel erection shall be pre-planned to ensure that the requirements of § 1926.753(d) are met.
Where employers elect, due to conditions specific to the site, to develop alternate means and methods that provide employee protection in accordance with § 1926.753(c)(5), § 1926.757(a)(4) or § 1926.757(e)(4), a site-specific erection plan shall be developed by a qualified person and be available at the work site. Guidelines for establishing a site-specific erection plan are contained in appendix A to this subpart.
[66 FR 5265, Jan. 18, 2001, as amended at 75 FR 48134, Aug. 9, 2010]
Shear connectors (such as headed steel studs, steel bars or steel lugs), reinforcing bars, deformed anchors or threaded studs shall not be attached to the top flanges of beams, joists or beam attachments so that they project vertically from or horizontally across the top flange of the member until after the metal decking, or other walking/working surface, has been installed.
Metal decking at roof and floor holes and openings shall be installed as follows:
Wire mesh, exterior plywood, or equivalent, shall be installed around columns where planks or metal decking do not fit tightly. The materials used must be of sufficient strength to provide fall protection for personnel and prevent objects from falling through.
[66 FR 5265, Jan. 18, 2001, as amended at 71 FR 2885, Jan. 18, 2006; 71 FR 16674, Apr. 3, 2006; 75 FR 27429, May 17, 2010; 85 FR 8745, Feb. 18, 2020]
Solid web structural members used as diagonal bracing shall be secured by at least one bolt per connection drawn up wrench-tight or the equivalent as specified by the project structural engineer of record.
Each column splice shall be designed to resist a minimum eccentric gravity load of 300 pounds (136.2 kg) located 18 inches (.46 m) from the extreme outer face of the column in each direction at the top of the column shaft.
Perimeter columns shall not be erected unless:
| Joist | Span |
|---|---|
| 8L1 | NM |
| 10K1 | NM |
| 12K1 | 23-0 |
| 12K3 | NM |
| 12K5 | NM |
| 14K1 | 27-0 |
| 14K3 | NM |
| 14K4 | NM |
| 14K6 | NM |
| 16K2 | 29-0 |
| 16K3 | 30-0 |
| 16K4 | 32-0 |
| 16K5 | 32-0 |
| 16K6 | NM |
| 16K7 | NM |
| 16K9 | NM |
| 18K3 | 31-0 |
| 18K4 | 32-0 |
| 18K5 | 33-0 |
| 18K6 | 35-0 |
| 18K7 | NM |
| 18K9 | NM |
| 18K10 | NM |
| 20K3 | 32-0 |
| 20K4 | 34-0 |
| 20K5 | 34-0 |
| 20K6 | 36-0 |
| 20K7 | 39-0 |
| 20K9 | 39-0 |
| 20K10 | NM |
| 22K4 | 34-0 |
| 22K5 | 35-0 |
| 22K6 | 36-0 |
| 22K7 | 40-0 |
| 22K9 | 40-0 |
| 22K10 | 40-0 |
| 22K11 | 40-0 |
| 24K4 | 36-0 |
| 24K5 | 38-0 |
| 24K6 | 39-0 |
| 24K7 | 43-0 |
| 24K8 | 43-0 |
| 24K9 | 44-0 |
| 24K10 | NM |
| 24K12 | NM |
| 26K5 | 38-0 |
| 26K6 | 39-0 |
| 26K7 | 43-0 |
| 26K8 | 44-0 |
| 26K9 | 45-0 |
| 26K10 | 49-0 |
| 26K12 | NM |
| 28K6 | 40-0 |
| 28K7 | 43-0 |
| 28K8 | 44-0 |
| 28K9 | 45-0 |
| 28K10 | 49-0 |
| 28K12 | 53-0 |
| 30K7 | 44-0 |
| 30K8 | 45-0 |
| 30K9 | 45-0 |
| 30K10 | 50-0 |
| 30K11 | 52-0 |
| 30K12 | 54-0 |
| 10KCS1 | NM |
| 10KCS2 | NM |
| 10KCS3 | NM |
| 12KCS1 | NM |
| 12KCS2 | NM |
| 12KCS3 | NM |
| 14KCS1 | NM |
| 14KCS2 | NM |
| 14KCS3 | NM |
| 16KCS2 | NM |
| 16KCS3 | NM |
| 16KCS4 | NM |
| 16KCS5 | NM |
| 18KCS2 | 35-0 |
| 18KCS3 | NM |
| 18KCS4 | NM |
| 18KCS5 | NM |
| 20KCS2 | 36-0 |
| 20KCS3 | 39-0 |
| 20KCS4 | NM |
| 20KCS5 | NM |
| 22KCS2 | 36-0 |
| 22KCS3 | 40-0 |
| 22KCS4 | NM |
| 22KCS5 | NM |
| 24KCS2 | 39-0 |
| 24KCS3 | 44-0 |
| 24KCS4 | NM |
| 24KCS5 | NM |
| 26KCS2 | 39-0 |
| 26KCS3 | 44-0 |
| 26KCS4 | NM |
| 26KCS5 | NM |
| 28KCS2 | 40-0 |
| 28KCS3 | 45-0 |
| 28KCS4 | 53-0 |
| 28KCS5 | 53-0 |
| 30KC53 | 45-0 |
| 30KCS4 | 54-0 |
| 30KCS5 | 54-0 |
| NM = diagonal bolted bridging not mandatory. |
| Joist | Span |
|---|---|
| 18LH02 | 33-0. |
| 18LH03 | NM. |
| 18LH04 | NM. |
| 18LH05 | NM. |
| 18LH06 | NM. |
| 18LH07 | NM. |
| 18LH08 | NM. |
| 18LH09 | NM. |
| 20LH02 | 33-0. |
| 20LH03 | 38-0. |
| 20LH04 | NM. |
| 20LH05 | NM. |
| 20LH06 | NM. |
| 20LH07 | NM. |
| 20LH08 | NM. |
| 20LH09 | NM. |
| 20LH10 | NM. |
| 24LH03 | 35-0. |
| 24LH04 | 39-0. |
| 24LH05 | 40-0. |
| 24LH06 | 45-0. |
| 24LH07 | NM. |
| 24LH08 | NM. |
| 24LH09 | NM. |
| 24LH10 | NM. |
| 24LH11 | NM. |
| 28LH05 | 42-0. |
| 28LH06 | 42-0. |
| 28LH07 | NM. |
| 28LH08 | NM. |
| 28LH09 | NM. |
| 28LH10 | NM. |
| 28LH11 | NM. |
| 28LH12 | NM. |
| 28LH13 | NM. |
| 32LH06 | 47-0 through 60-0. |
| 32LH07 | 47-0 through 60-0. |
| 32LH08 | 55-0 through 60-0. |
| 32LH09 | NM through 60-0. |
| 32LH10 | NM through 60-0. |
| 32LH11 | NM through 60-0. |
| 32LH12 | NM through 60-0. |
| 32LH13 | NM through 60-0. |
| 32LH14 | NM through 60-0. |
| 32LH15 | NM through 60-0. |
| 36LH07 | 47-0 through 60-0. |
| 36LH08 | 47-0 through 60-0. |
| 36LH09 | 57-0 through 60-0. |
| 36LH10 | NM through 60-0. |
| 36LH11 | NM through 60-0. |
| 36LH12 | NM through 60-0. |
| 36LH13 | NM through 60-0. |
| 36LH14 | NM through 60-0. |
| 36LH15 | NM through 60-0. |
| NM = diagonal bolted bridging not mandatory. |
[66 FR 5265, Jan. 18, 2001, as amended at 85 FR 8745, Feb. 18, 2020]
All materials, equipment, and tools, which are not in use while aloft, shall be secured against accidental displacement.
On multi-story structures, perimeter safety cables shall be installed at the final interior and exterior perimeters of the floors as soon as the metal decking has been installed.
Each connector shall:
A controlled decking zone may be established in that area of the structure over 15 and up to 30 feet above a lower level where metal decking is initially being installed and forms the leading edge of a work area. In each CDZ, the following shall apply:
Fall protection provided by the steel erector shall remain in the area where steel erection activity has been completed, to be used by other trades, only if the controlling contractor or its authorized representative:
The following provisions supplement the requirements of § 1926.21 regarding the hazards addressed in this subpart.
Training required by this section shall be provided by a qualified person(s).
The employer shall train each employee exposed to a fall hazard in accordance with the requirements of this section. The employer shall institute a training program and ensure employee participation in the program. The program shall include training and instruction in the following areas:
In addition to the training required in paragraphs (a) and (b) of this section, the employer shall provide special training to employees engaged in the following activities.
The employer shall ensure that each employee who performs multiple lift rigging has been provided training in the following areas:
The employer shall ensure that each connector has been provided training in the following areas:
Where CDZs are being used, the employer shall assure that each employee has been provided training in the following areas:
[66 FR 5265, Jan. 18, 2001, as amended at 73 FR 75589, Dec. 12, 2008; 85 FR 8745, Feb. 18, 2020]
This appendix serves as a guideline to assist employers who elect to develop a site-specific erection plan in accordance with § 1926.752(e) with alternate means and methods to provide employee protection in accordance with § 1926.752(e), § 1926.753(c)(5), § 1926.757(a)(4) and § 1926.757(e)(4).
Pre-construction conference(s) and site inspection(s) are held between the erector and the controlling contractor, and others such as the project engineer and fabricator before the start of steel erection. The purpose of such conference(s) is to develop and review the site-specific erection plan that will meet the requirements of this section.
In developing a site-specific erection plan, a steel erector considers the following elements:
The plan:
The training requirements of § 1926.761 will be deemed to have been met if employees have completed a training course on steel erection, including instruction in the provisions of this standard, that has been approved by the U.S. Department of Labor Bureau of Apprenticeship.
In multi-story structures, when holes in the column web are used for perimeter safety cables, the column splice must be placed sufficiently high so as not to interfere with any attachments to the column necessary for the column splice. Column splices are recommended to be placed at every other or fourth levels as design allows. Column splices at third levels are detrimental to the erection process and should be avoided if possible.
Safety net systems and their use shall comply with the following provisions:
| Vertical distance from working level to horizontal plane of net | Minimum required horizontal distance of outer edge of net from the edge of the working surface |
|---|---|
| Up to 5 feet | 8 feet |
| More than 5 feet up to 10 feet | 10 feet |
| More than 10 feet | 13 feet |
Positioning device systems and their use shall conform to the following provisions:
Clipped end connections are connection material on the end of a structural member which has a notch at the bottom and/or top to allow the bolt(s) of the first member placed on the opposite side of the central member to remain in place. The notch(es) fits around the nut or bolt head of the opposing member to allow the second member to be bolted up without removing the bolt(s) holding the first member.
Staggered connections are connection material on a structural member in which all of the bolt holes in the common member web are not shared by the two incoming members in the final connection. The extra hole in the column web allows the erector to maintain at least a one bolt connection at all times while making the double connection.
The employer shall maintain a check-in/check-out procedure that will ensure that above-ground personnel can determine an accurate count of the number of persons underground in the event of an emergency. However, this procedure is not required when the construction of underground facilities designed for human occupancy has been sufficiently completed so that the permanent environmental controls are effective, and when the remaining construction activity will not cause any environmental hazard or structural failure within the facilities.
All employees shall be instructed in the recognition and avoidance of hazards associated with underground construction activities including, where appropriate, the following subjects:
When a shaft is used as a means of egress, the employer shall make advance arrangements for power-assisted hoisting capability to be readily available in an emergency, unless the regular hoisting means can continue to function in the event of an electrical power failure at the jobsite. Such hoisting means shall be designed so that the load hoist drum is powered in both directions of rotation and so that the brake is automatically applied upon power release or failure.
The employer must provide self-rescuers approved by the National Institute for Occupational Safety and Health under 42 CFR part 84. The respirators must be immediately available to all employees at work stations in underground areas where employees might be trapped by smoke or gas. The selection, issuance, use, and care of respirators must be in accordance with 29 CFR 1926.103.
At least one designated person shall be on duty above ground whenever any employee is working underground. This designated person shall be responsible for securing immediate aid and keeping an accurate count of employees underground in case of emergency. The designated person must not be so busy with other responsibilities that the counting function is encumbered.
Each employee underground shall have an acceptable portable hand lamp or cap lamp in his or her work area for emergency use, unless natural light or an emergency lighting system provides adequate illumination for escape.
Underground construction operations shall be classified as potentially gassy if either:
Underground construction operations shall be classified as gassy if:
Underground construction gassy operations may be declassified to Potentially Gassy when air monitoring results remain under 10 percent of the lower explosive limit for methane or other flammable gases for three consecutive days.
Air quality limits and control requirements for construction are found in § 1926.55, except as modified by this section.
Proximity to fuel tanks, sewers, gas lines, old landfills, coal deposits, and swamps;
Geological studies of the jobsite, particularly involving the soil type and its permeability;
Presence of air contaminants in nearby jobsites, changes in levels of substances monitored on the prior shift; and
The use of diesel engines, use of explosives, use of fuel gas, volume and flow of ventilation, visible atmospheric conditions, decompression of the atmosphere, welding, cutting and hot work, and employees' physical reactions to working underground.
Operations which meet the criteria for potentially gassy and gassy operations set forth in paragraph (h) of this section shall be subject to the additional monitoring requirements of this paragraph.
A record of all air quality tests shall be maintained above ground at the worksite and be made available to the Secretary of Labor upon request. The record shall include the location, date, time, substance and amount monitored. Records of exposures to toxic substances shall be retained in accordance with § 1910.33 of this chapter. All other air quality test records shall be retained until completion of the project.
Fire prevention and protection requirements applicable to underground construction operations are found in subpart F of this part, except as modified by the following additional standards.
Portal openings and access areas shall be guarded by shoring, fencing, head walls, shotcreting or other equivalent protection to ensure safe access of employees and equipment. Adjacent areas shall be scaled or otherwise secured to prevent loose soil, rock, or fractured materials from endangering the portal and access area.
The employer shall ensure ground stability in hazardous subsidence areas by shoring, by filling in, or by erecting barricades and posting warning signs to prevent entry.
This paragraph applies in addition to the requirements for blasting and explosives operations, including handling of misfires, which are found in subpart U of this part.
This paragraph applies in addition to the general requirements for electrical safety which are found in subpart K of this part.
Except as modified by this paragraph (t), employers must: Comply with the requirements of subpart CC of this part, except that the limitation in § 1926.1431(a) does not apply to the routine access of employees to an underground worksite via a shaft; ensure that material hoists comply with § 1926.552(a) and (b) of this part; and ensure that personnel hoists comply with the personnel-hoists requirements of § 1926.552(a) and (c) of this part and the elevator requirements of § 1926.552(a) and (d) of this part.
Cranes shall be equipped with a limit switch to prevent overtravel at the boom tip. Limit switches are to be used only to limit travel of loads when operational controls malfunction and shall not be used as a substitute for other operational controls.
“Accept”—Any device, equipment, or appliance that is either approved by MSHA and maintained in permissible condition, or is listed or labeled for the class and location under subpart K of this part.
“Rapid Excavation Machine”—Tunnel boring machines, shields, roadheaders, or any other similar excavation machine.
[54 FR 23850, June 2, 1989; 58 FR 35311, June 30, 1993, as amended at 61 FR 5510, Feb. 13, 1996; 63 FR 1297, Jan. 8, 1998; 71 FR 16674, Apr. 3, 2006; 75 FR 48135, Aug. 9, 2010; 77 FR 49728, Aug. 17, 2012; 78 FR 23841, Apr. 24, 2013; 84 FR 21577, May 14, 2019]
Time of Decompression for This Lock
__ pounds to __ pounds in __ minutes.
__ pounds to __ pounds in __ minutes.
This form shall be posted in the Man Lock at all times.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 47 FR 14696, 14706, Apr. 6, 1982; 51 FR 25318, July 11, 1986; 61 FR 5510, Feb. 13, 1996]
Usually shown as pounds per square inch. (p.s.i.)
1. Explanation. The decompression tables are computed for working chamber pressures from 0 to 14 pounds, and from 14 to 50 pounds per square inch gauge inclusive by 2-pound increments and for exposure times for each pressure extending from one-half to over 8 hours inclusive. Decompressions will be conducted by two or more stages with a maximum of four stages, the latter for a working chamber pressure of 40 pounds per square inch gauge or over.
Stage 1 consists of a reduction in ambient pressure ranging from 10 to a maximum of 16 pounds per square inch, but in no instance will the pressure be reduced below 4 pounds at the end of stage 1. This reduction in pressure in stage 1 will always take place at a rate not greater than 5 pounds per minute.
Further reduction in pressure will take place during stage 2 and subsequent stages as required at a slower rate, but in no event at a rate greater than 1 pound per minute.
Decompression Table No. 1 indicates in the body of the table the total decompression time in minutes for various combinations of working chamber pressure and exposure time.
Decompression Table No. 2 indicates for the same various combinations of working chamber pressure and exposure time the following:
a. The number of stages required;
b. The reduction in pressure and the terminal pressure for each required stage;
c. The time in minutes through which the reduction in pressure is accomplished for each required stage;
d. The pressure reduction rate in minutes per pound for each required stage;
| Examples | Minutes |
|---|---|
| Example No. 1: 4 hours working period at 20 pounds gauge. | |
| Decompression Table No. 1: 20 pounds for 4 hours, total decompression time | 43 |
| Decompression Table No. 2: | |
| Stage 1: Reduce pressure from 20 pounds to 4 pounds at the uniform rate of 5 pounds per minute. | |
| Elapsed time stage 1: 16/5 | 3 |
| Stage 2 (final stage): Reduce pressure at a uniform rate from 4 pounds to 0-pound gage over a period of 40 minutes. | |
| Rate—0.10 pound per minute or 10 minutes per pound. | |
| Stage 2 (final) elapsed time | 40 |
| Total time | 43 |
| Example No. 2: 5-hour working period at 24 pounds gage. | |
| Decompression Table No. 1: 24 pounds for 5 hours, total decompression time | 117 |
| Decompression Table No. 2: | |
| Stage 1: Reduce pressure from 24 pounds to 8 pounds at the uniform rate of 5 pounds per minute. | |
| Elapsed time stage 1: 16/5 | 3 |
| Stage 2: Reduce pressure at a uniform rate from 8 pounds to 4 pounds over a period of 4 minutes. Rate, 1 pound per minute elapsed time, stage 2 | 4 |
| Transfer men to special decompression chamber maintaining the 4-pound pressure during the transfer operation. | |
| Stage 3 (final stage): In the special decompression chamber, reduce the pressure at a uniform rate from 4 pounds to 0-pound gage over a period of 110 minutes. Rate, 0.037 pound per minute or 27.5 minutes per pound. Stage 3 (final) elapsed time | 110 |
| Total time | 117 |
| Work pressure p.s.i.g. | Working period hours | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 ⁄ 2 | 1 | 1 1 ⁄ 2 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | Over 8 | |
| 9 to 12 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
| 14 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 16 | 16 | 33 |
| 16 | 7 | 7 | 7 | 7 | 7 | 7 | 17 | 33 | 48 | 48 | 62 |
| 18 | 7 | 7 | 7 | 8 | 11 | 17 | 48 | 63 | 63 | 73 | 87 |
| 20 | 7 | 7 | 8 | 15 | 15 | 43 | 63 | 73 | 83 | 103 | 113 |
| 22 | 9 | 9 | 16 | 24 | 38 | 68 | 93 | 103 | 113 | 128 | 133 |
| 24 | 11 | 12 | 23 | 27 | 52 | 92 | 117 | 122 | 127 | 137 | 151 |
| 26 | 13 | 14 | 29 | 34 | 69 | 104 | 126 | 141 | 142 | 142 | 163 |
| 28 | 15 | 23 | 31 | 41 | 98 | 127 | 143 | 153 | 153 | 165 | 183 |
| 30 | 17 | 28 | 38 | 62 | 105 | 143 | 165 | 168 | 178 | 188 | 204 |
| 32 | 19 | 35 | 43 | 85 | 126 | 163 | 178 | 193 | 203 | 213 | 226 |
| 34 | 21 | 39 | 58 | 98 | 151 | 178 | 195 | 218 | 223 | 233 | 248 |
| 36 | 24 | 44 | 63 | 113 | 170 | 198 | 223 | 233 | 243 | 253 | 273 |
| 38 | 28 | 49 | 73 | 128 | 178 | 203 | 223 | 238 | 253 | 263 | 278 |
| 40 | 31 | 49 | 84 | 143 | 183 | 213 | 233 | 248 | 258 | 278 | 288 |
| 42 | 37 | 56 | 102 | 144 | 189 | 215 | 245 | 260 | 263 | 268 | 293 |
| 44 | 43 | 64 | 118 | 154 | 199 | 234 | 254 | 264 | 269 | 269 | 293 |
| 46 | 44 | 74 | 139 | 171 | 214 | 244 | 269 | 274 | 289 | 299 | 318 |
| 48 | 51 | 89 | 144 | 189 | 229 | 269 | 299 | 309 | 319 | 319 | |
| 50 | 58 | 94 | 164 | 209 | 249 | 279 | 309 | 329 |
| Working chamber pressure p.s.i.g. | Working period hours | Decompression data | |||||
|---|---|---|---|---|---|---|---|
| Stage No. | Pressure reduc. p.s.i.g. | Time in stage minutes | Pressure reduc. rate Min/pound | Total time decompress minutes | |||
| From | To | ||||||
| 14 | 1 ⁄ 2 | 1 | 14 | 4 | 2 | 0.20 | 6 |
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 1 | 1 | 14 | 4 | 2 | 0.20 | 6 | |
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 1 1 ⁄ 2 | 1 | 14 | 4 | 2 | 0.20 | 6 | |
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 2 | 1 | 14 | 4 | 2 | 0.20 | 6 | |
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 3 | 1 | 14 | 4 | 2 | 0.20 | 6 | |
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 4 | 1 | 14 | 0 | 2 | 0.20 | 6 | |
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 5 | 1 | 14 | 4 | 2 | 0.20 | 6 | |
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 6 | 1 | 14 | 4 | 2 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 6 | ||
| 7 | 1 | 14 | 4 | 2 | 0.20 | ||
| 2 | 4 | 0 | 14 | 3.50 | 16 | ||
| 8 | 1 | 14 | 4 | 2 | 0.20 | ||
| 2 | 4 | 0 | 14 | 3.50 | 16 | ||
| Over 8 | 1 | 14 | 4 | 2 | 0.20 | ||
| 2 | 4 | 0 | 30 | 7.50 | 32 | ||
| 16 | 1 ⁄ 2 | 1 | 16 | 4 | 3 | 0.20 | |
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 1 | 1 | 16 | 4 | 3 | 0.20 | 7 | |
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 1 1 ⁄ 2 | 1 | 16 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 2 | 1 | 16 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 3 | 1 | 16 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 4 | 1 | 14 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 5 | 1 | 14 | 4 | 3 | 0.20 | 7 | |
| 2 | 4 | 0 | 4 | 3.50 | 17 | ||
| 6 | 1 | 14 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 30 | 7.50 | 33 | ||
| 7 | 1 | 14 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 45 | 11.25 | 48 | ||
| 8 | 1 | 14 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 45 | 11.25 | 48 | ||
| Over 8 | 1 | 14 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 60 | 15.00 | 63 | ||
| 18 | 1 ⁄ 2 | 1 | 18 | 4 | 3 | 0.20 | |
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 1 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 1 1 ⁄ 2 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 2 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 5 | 1.25 | 8 | ||
| 3 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 8 | 2.00 | 11 | ||
| 4 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 14 | 3.50 | 17 | ||
| 5 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 45 | 11.25 | 48 | ||
| 6 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 60 | 15.00 | 63 | ||
| 7 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 60 | 15.00 | 63 | ||
| 8 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 70 | 17.50 | 73 | ||
| Over 8 | 1 | 18 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 84 | 21.00 | 87 | ||
| 20 | 1 ⁄ 2 | 1 | 20 | 4 | 3 | 0.20 | |
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 1 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 4 | 1.00 | 7 | ||
| 1 1 ⁄ 2 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 5 | 1.25 | 8 | ||
| 2 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 12 | 3.00 | 15 | ||
| 3 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 12 | 3.00 | 15 | ||
| 4 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 40 | 10.00 | 43 | ||
| 5 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 60 | 15.00 | 63 | ||
| 6 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 70 | 17.50 | 73 | ||
| 7 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 80 | 20.00 | 83 | ||
| 8 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 100 | 25.00 | 103 | ||
| Over 8 | 1 | 20 | 4 | 3 | 0.20 | ||
| 2 | 4 | 0 | 110 | 27.50 | 113 | ||
| 22 | 1 ⁄ 2 | 1 | 22 | 6 | 3 | 0.20 | |
| 2 | 6 | 0 | 6 | 1.00 | 9 | ||
| 1 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 6 | 1.00 | 9 | ||
| 1 1 ⁄ 2 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 13 | 2.20 | 16 | ||
| 2 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 21 | 3.50 | 24 | ||
| 3 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 35 | 5.85 | 38 | ||
| 4 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 65 | 10.83 | 68 | ||
| 5 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 90 | 15.00 | 93 | ||
| 6 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 4 | 0 | 100 | 16.67 | 103 | ||
| 7 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 110 | 18.35 | 113 | ||
| 8 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 125 | 20.80 | 128 | ||
| Over 8 | 1 | 22 | 6 | 3 | 0.20 | ||
| 2 | 6 | 0 | 130 | 21.70 | 133 | ||
| 24 | 1 ⁄ 2 | 1 | 24 | 8 | 3 | 0.20 | |
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 4 | 1.00 | 11 | ||
| 1 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 5 | 1.25 | 12 | ||
| 1 1 ⁄ 2 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 16 | 4.00 | 23 | ||
| 2 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 20 | 5.00 | 27 | ||
| 3 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 45 | 11.25 | 52 | ||
| 4 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 85 | 21.25 | 92 | ||
| 5 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 110 | 27.50 | 117 | ||
| 6 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 115 | 28.80 | 122 | ||
| 7 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 120 | 30.00 | 127 | ||
| 8 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 4 | 1.00 | |||
| 3 | 4 | 0 | 130 | 32.50 | 137 | ||
| Over 8 | 1 | 24 | 8 | 3 | 0.20 | ||
| 2 | 8 | 4 | 8 | 2.00 | |||
| 3 | 4 | 0 | 140 | 35.00 | 151 | ||
| 26 | 1 ⁄ 2 | 1 | 26 | 10 | 3 | 0.20 | |
| 2 | 10 | 4 | 6 | 1.00 | |||
| 3 | 4 | 0 | 4 | 1.00 | 13 | ||
| 1 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 6 | 1.00 | |||
| 3 | 4 | 0 | 5 | 1.25 | 14 | ||
| 1 1 ⁄ 2 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 6 | 1.00 | |||
| 3 | 4 | 0 | 20 | 5.00 | 29 | ||
| 2 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 6 | 1.00 | |||
| 3 | 4 | 0 | 25 | 6.25 | 34 | ||
| 3 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 6 | 1.00 | |||
| 3 | 4 | 0 | 60 | 15.00 | 69 | ||
| 4 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 6 | 1.00 | |||
| 3 | 4 | 0 | 95 | 23.75 | 104 | ||
| 5 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 8 | 1.33 | |||
| 3 | 4 | 0 | 115 | 28.80 | 126 | ||
| 6 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 8 | 1.33 | |||
| 3 | 4 | 0 | 130 | 32.50 | 141 | ||
| 7 | 1 | 26 | 10 | 3 | 2.20 | ||
| 2 | 10 | 4 | 9 | 1.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 142 | ||
| 8 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 9 | 1.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 142 | ||
| Over 8 | 1 | 26 | 10 | 3 | 0.20 | ||
| 2 | 10 | 4 | 30 | 5.00 | |||
| 3 | 4 | 0 | 30 | 32.50 | 163 | ||
| 28 | 1 ⁄ 2 | 1 | 28 | 12 | 3 | 0.20 | |
| 2 | 12 | 4 | 8 | 1.00 | |||
| 3 | 4 | 0 | 4 | 1.00 | 15 | ||
| 1 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 8 | 1.00 | |||
| 3 | 4 | 0 | 12 | 3.00 | 23 | ||
| 1 1 ⁄ 2 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 8 | 1.00 | |||
| 3 | 4 | 0 | 20 | 5.00 | 31 | ||
| 2 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 8 | 1.00 | |||
| 3 | 4 | 0 | 30 | 7.50 | 41 | ||
| 3 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 10 | 1.25 | |||
| 3 | 4 | 0 | 85 | 21.20 | 98 | ||
| 4 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 14 | 1.75 | |||
| 3 | 4 | 0 | 110 | 27.50 | 127 | ||
| 5 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 20 | 2.50 | |||
| 3 | 4 | 0 | 120 | 30.00 | 143 | ||
| 6 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 20 | 2.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 153 | ||
| 7 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 20 | 2.50 | |||
| 3 | 4 | 0 | 120 | 32.50 | 153 | ||
| 8 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 32 | 4.00 | |||
| 3 | 4 | 0 | 130 | 32.50 | 165 | ||
| Over 8 | 1 | 28 | 12 | 3 | 0.20 | ||
| 2 | 12 | 4 | 50 | 6.25 | |||
| 3 | 4 | 0 | 130 | 32.50 | 183 | ||
| 30 | 1 ⁄ 2 | 1 | 30 | 14 | 3 | 0.20 | |
| 2 | 14 | 4 | 10 | 1.00 | |||
| 3 | 4 | 0 | 4 | 1.00 | 17 | ||
| 1 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 10 | 1.00 | |||
| 3 | 4 | 0 | 15 | 3.75 | 28 | ||
| 1 1 ⁄ 2 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 10 | 1.00 | |||
| 3 | 4 | 0 | 25 | 6.25 | 38 | ||
| 2 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 14 | 1.40 | |||
| 3 | 4 | 0 | 45 | 11.25 | 62 | ||
| 3 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 17 | 1.70 | |||
| 3 | 4 | 0 | 85 | 21.20 | 105 | ||
| 4 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 30 | 3.00 | |||
| 3 | 4 | 0 | 110 | 27.50 | 143 | ||
| 5 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 35 | 3.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 165 | ||
| 6 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 35 | 3.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 168 | ||
| 7 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 45 | 4.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 178 | ||
| 8 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 55 | 5.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 188 | ||
| Over 8 | 1 | 30 | 14 | 3 | 0.20 | ||
| 2 | 14 | 4 | 71 | 7.10 | |||
| 3 | 4 | 0 | 130 | 32.50 | 204 | ||
| 32 | 1 ⁄ 2 | 1 | 32 | 16 | 3 | 0.20 | |
| 2 | 16 | 4 | 12 | 1.00 | |||
| 3 | 4 | 0 | 4 | 1.00 | 19 | ||
| 1 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 12 | 1.00 | |||
| 3 | 4 | 0 | 20 | 5.00 | 35 | ||
| 1 1 ⁄ 2 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 15 | 1.25 | |||
| 3 | 4 | 0 | 25 | 6.25 | 43 | ||
| 2 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 22 | 1.83 | |||
| 3 | 4 | 0 | 60 | 15.00 | 85 | ||
| 3 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 28 | 2.33 | |||
| 3 | 4 | 0 | 95 | 23.75 | 126 | ||
| 4 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 40 | 3.33 | |||
| 3 | 4 | 0 | 120 | 30.00 | 163 | ||
| 5 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 45 | 3.75 | |||
| 3 | 4 | 0 | 130 | 32.50 | 178 | ||
| 6 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 60 | 5.00 | |||
| 3 | 4 | 0 | 130 | 32.50 | 193 | ||
| 7 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 70 | 5.83 | |||
| 3 | 4 | 0 | 130 | 32.50 | 203 | ||
| 8 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 80 | 6.67 | |||
| 3 | 4 | 0 | 130 | 32.50 | 213 | ||
| Over 8 | 1 | 32 | 16 | 3 | 0.20 | ||
| 2 | 16 | 4 | 93 | 7.75 | |||
| 3 | 4 | 0 | 130 | 32.50 | 226 | ||
| 34 | 1 ⁄ 2 | 1 | 34 | 18 | 3 | 0.20 | |
| 2 | 18 | 4 | 14 | 1.00 | |||
| 3 | 4 | 0 | 4 | 1.00 | 21 | ||
| 1 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 14 | 1.00 | |||
| 3 | 4 | 0 | 22 | 5.50 | 39 | ||
| 1 1 ⁄ 2 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 25 | 1.80 | |||
| 3 | 4 | 0 | 30 | 7.50 | 58 | ||
| 2 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 35 | 2.50 | |||
| 3 | 4 | 0 | 60 | 15.00 | 98 | ||
| 3 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 43 | 3.10 | |||
| 3 | 4 | 0 | 105 | 26.25 | 151 | ||
| 4 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 55 | 3.93 | |||
| 3 | 4 | 0 | 120 | 30.00 | 178 | ||
| 5 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 62 | 4.43 | |||
| 3 | 4 | 0 | 130 | 32.50 | 195 | ||
| 6 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 85 | 6.07 | |||
| 3 | 4 | 0 | 130 | 32.50 | 218 | ||
| 7 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 90 | 6.43 | |||
| 3 | 4 | 0 | 130 | 32.50 | 223 | ||
| 8 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 100 | 7.15 | |||
| 3 | 4 | 0 | 130 | 32.50 | 233 | ||
| Over 8 | 1 | 34 | 18 | 3 | 0.20 | ||
| 2 | 18 | 4 | 115 | 8.23 | |||
| 3 | 4 | 0 | 130 | 32.50 | 248 | ||
| 36 | 1 ⁄ 2 | 1 | 36 | 20 | 3 | 0.20 | |
| 2 | 20 | 4 | 16 | 1.00 | |||
| 3 | 4 | 0 | 5 | 1.25 | 24 | ||
| 1 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 16 | 1.00 | |||
| 3 | 4 | 0 | 25 | 6.25 | 44 | ||
| 1 1 ⁄ 2 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 30 | 1.88 | |||
| 3 | 4 | 0 | 30 | 7.50 | 63 | ||
| 2 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 40 | 2.50 | |||
| 3 | 4 | 0 | 70 | 17.50 | 113 | ||
| 3 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 52 | 3.25 | |||
| 3 | 4 | 0 | 115 | 28.75 | 170 | ||
| 4 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 65 | 4.06 | |||
| 3 | 4 | 0 | 130 | 32.50 | 198 | ||
| 5 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 90 | 5.63 | |||
| 3 | 4 | 0 | 130 | 32.50 | 223 | ||
| 6 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 100 | 6.25 | |||
| 3 | 4 | 0 | 130 | 32.50 | 233 | ||
| 7 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 110 | 6.88 | |||
| 3 | 4 | 0 | 130 | 32.50 | 243 | ||
| 8 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 120 | 7.50 | |||
| 3 | 4 | 0 | 130 | 32.50 | 253 | ||
| Over 8 | 1 | 36 | 20 | 3 | 0.20 | ||
| 2 | 20 | 4 | 140 | 8.75 | |||
| 3 | 4 | 0 | 130 | 32.50 | 273 | ||
| 38 | 1 ⁄ 2 | 1 | 38 | 22 | 3 | 0.20 | |
| 2 | 22 | 6 | 16 | 1.00 | |||
| 3 | 6 | 0 | 9 | 1.50 | 28 | ||
| 1 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 16 | 1.00 | |||
| 3 | 6 | 0 | 30 | 5.00 | 49 | ||
| 1 1 ⁄ 2 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 20 | 1.25 | |||
| 3 | 6 | 0 | 50 | 8.34 | 73 | ||
| 2 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 30 | 1.88 | |||
| 3 | 6 | 0 | 95 | 15.83 | 128 | ||
| 3 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 35 | 2.19 | |||
| 3 | 6 | 0 | 140 | 23.35 | 178 | ||
| 4 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 50 | 3.12 | |||
| 3 | 6 | 0 | 150 | 25.00 | 203 | ||
| 5 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 55 | 3.44 | |||
| 3 | 6 | 0 | 165 | 27.50 | 223 | ||
| 6 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 70 | 4.38 | |||
| 3 | 6 | 0 | 165 | 27.50 | 238 | ||
| 7 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 85 | 5.32 | |||
| 3 | 6 | 0 | 165 | 27.50 | 253 | ||
| 8 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 95 | 5.93 | |||
| 3 | 6 | 0 | 165 | 27.50 | 263 | ||
| Over 8 | 1 | 38 | 22 | 3 | 0.20 | ||
| 2 | 22 | 6 | 110 | 6.88 | |||
| 3 | 6 | 0 | 165 | 27.50 | 278 | ||
| 40 | 1 ⁄ 2 | 1 | 40 | 24 | 3 | 0.20 | |
| 2 | 24 | 8 | 16 | 1.00 | |||
| 3 | 8 | 4 | 4 | 1.00 | |||
| 4 | 4 | 0 | 8 | 2.00 | 31 | ||
| 1 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 16 | 1.00 | |||
| 3 | 8 | 4 | 5 | 1.25 | |||
| 4 | 4 | 0 | 25 | 6.25 | 49 | ||
| 1 1 ⁄ 2 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 16 | 1.00 | |||
| 3 | 8 | 4 | 20 | 5.00 | |||
| 4 | 4 | 0 | 45 | 11.25 | 84 | ||
| 2 | 2 | 40 | 24 | 3 | 0.20 | ||
| 1 | 24 | 8 | 25 | 1.56 | |||
| 3 | 8 | 4 | 20 | 5.00 | |||
| 4 | 4 | 0 | 95 | 23.75 | 143 | ||
| 3 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 30 | 1.88 | |||
| 3 | 8 | 4 | 30 | 7.50 | |||
| 4 | 4 | 0 | 120 | 30.00 | 183 | ||
| 4 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 45 | 2.81 | |||
| 3 | 8 | 4 | 35 | 8.75 | |||
| 4 | 4 | 0 | 130 | 32.50 | 213 | ||
| 5 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 47 | 2.94 | |||
| 3 | 8 | 4 | 53 | 13.25 | |||
| 4 | 4 | 0 | 130 | 32.50 | 233 | ||
| 6 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 55 | 3.44 | |||
| 3 | 8 | 4 | 60 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 248 | ||
| 7 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 65 | 4.06 | |||
| 3 | 8 | 4 | 60 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 258 | ||
| 8 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 75 | 4.70 | |||
| 3 | 8 | 4 | 60 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 268 | ||
| Over 8 | 1 | 40 | 24 | 3 | 0.20 | ||
| 2 | 24 | 8 | 95 | 5.93 | |||
| 3 | 8 | 4 | 60 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 288 | ||
| 42 | 1 ⁄ 2 | 1 | 42 | 26 | 3 | 0.20 | |
| 2 | 26 | 10 | 16 | 1.00 | |||
| 3 | 10 | 4 | 6 | 1.00 | |||
| 4 | 4 | 0 | 12 | 3.00 | 37 | ||
| 1 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 16 | 1.00 | |||
| 3 | 10 | 4 | 12 | 2.00 | |||
| 4 | 4 | 0 | 25 | 6.25 | 56 | ||
| 1 1 ⁄ 2 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 16 | 1.00 | |||
| 3 | 10 | 4 | 23 | 3.83 | |||
| 4 | 4 | 0 | 60 | 15.00 | 102 | ||
| 2 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 16 | 1.00 | |||
| 3 | 10 | 4 | 30 | 5.00 | |||
| 4 | 4 | 0 | 95 | 23.75 | 144 | ||
| 3 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 16 | 1.00 | |||
| 3 | 10 | 4 | 50 | 8.34 | |||
| 4 | 4 | 0 | 120 | 30.00 | 189 | ||
| 4 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 17 | 1.06 | |||
| 3 | 10 | 4 | 65 | 10.83 | |||
| 4 | 4 | 0 | 130 | 32.50 | 215 | ||
| 5 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 27 | 1.69 | |||
| 3 | 10 | 4 | 85 | 14.18 | |||
| 4 | 4 | 0 | 130 | 32.50 | 245 | ||
| 6 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 27 | 1.69 | |||
| 3 | 10 | 4 | 100 | 16.67 | |||
| 4 | 4 | 0 | 130 | 32.50 | 260 | ||
| 7 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 30 | 1.88 | |||
| 3 | 10 | 4 | 100 | 16.67 | |||
| 4 | 4 | 0 | 130 | 32.50 | 263 | ||
| 8 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 35 | 2.19 | |||
| 3 | 10 | 4 | 100 | 16.67 | |||
| 4 | 4 | 0 | 130 | 32.50 | 268 | ||
| Over 8 | 1 | 42 | 26 | 3 | 0.20 | ||
| 2 | 26 | 10 | 60 | 3.75 | |||
| 3 | 10 | 4 | 100 | 16.67 | |||
| 4 | 4 | 0 | 130 | 32.50 | 293 | ||
| 44 | 1 ⁄ 2 | 1 | 44 | 28 | 3 | 0.20 | |
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 8 | 1.00 | |||
| 4 | 4 | 0 | 16 | 4.00 | 43 | ||
| 1 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 20 | 2.50 | |||
| 4 | 4 | 0 | 25 | 6.25 | 64 | ||
| 1 1 ⁄ 2 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 27 | 3.38 | |||
| 4 | 4 | 0 | 72 | 18.00 | 118 | ||
| 2 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 40 | 5.00 | |||
| 4 | 4 | 0 | 95 | 23.75 | 154 | ||
| 3 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 60 | 7.50 | |||
| 4 | 4 | 0 | 120 | 30.00 | 199 | ||
| 4 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 85 | 10.62 | |||
| 4 | 4 | 0 | 130 | 32.50 | 234 | ||
| 5 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 105 | 13.13 | |||
| 4 | 4 | 0 | 130 | 32.50 | 254 | ||
| 6 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 115 | 14.38 | |||
| 4 | 4 | 0 | 130 | 32.50 | 264 | ||
| 7 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 120 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 269 | ||
| 8 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 16 | 1.00 | |||
| 3 | 12 | 4 | 120 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 269 | ||
| Over 8 | 1 | 44 | 28 | 3 | 0.20 | ||
| 2 | 28 | 12 | 40 | 2.50 | |||
| 3 | 12 | 4 | 120 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 293 | ||
| 46 | 1 ⁄ 2 | 1 | 46 | 30 | 3 | 0.20 | |
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 10 | 1.00 | |||
| 4 | 4 | 0 | 15 | 3.75 | 44 | ||
| 1 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 25 | 2.50 | |||
| 4 | 4 | 0 | 30 | 7.50 | 74 | ||
| 1 1 ⁄ 2 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 35 | 3.50 | |||
| 4 | 4 | 0 | 85 | 21.20 | 139 | ||
| 2 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 47 | 4.70 | |||
| 4 | 4 | 0 | 105 | 26.25 | 171 | ||
| 3 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 65 | 6.50 | |||
| 4 | 4 | 0 | 130 | 32.50 | 214 | ||
| 4 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 95 | 9.50 | |||
| 4 | 4 | 0 | 130 | 32.50 | 244 | ||
| 5 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 120 | 12.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 269 | ||
| 6 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 125 | 12.50 | |||
| 4 | 4 | 0 | 130 | 32.50 | 274 | ||
| 7 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 34 | 14 | 16 | 1.00 | |||
| 3 | 10 | 4 | 140 | 14.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 289 | ||
| 8 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 16 | 1.00 | |||
| 3 | 14 | 4 | 150 | 15.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 299 | ||
| Over 8 | 1 | 46 | 30 | 3 | 0.20 | ||
| 2 | 30 | 14 | 25 | 1.56 | |||
| 3 | 14 | 4 | 160 | 16.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 318 | ||
| 48 | 1 ⁄ 2 | 1 | 48 | 32 | 3 | 0.20 | |
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 12 | 1.00 | |||
| 4 | 4 | 0 | 20 | 5.00 | 51 | ||
| 1 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 35 | 2.92 | |||
| 4 | 4 | 0 | 35 | 8.75 | 89 | ||
| 1 1 ⁄ 2 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 45 | 3.75 | |||
| 4 | 4 | 0 | 80 | 20.00 | 144 | ||
| 2 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 60 | 5.00 | |||
| 4 | 4 | 0 | 110 | 27.50 | 189 | ||
| 3 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 90 | 7.50 | |||
| 4 | 4 | 0 | 120 | 30.00 | 229 | ||
| 4 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 120 | 10.00 | |||
| 4 | 4 | 0 | 130 | 32.50 | 269 | ||
| 5 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 140 | 11.67 | |||
| 4 | 4 | 0 | 130 | 32.50 | 209 | ||
| 6 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 160 | 13.33 | |||
| 4 | 4 | 0 | 130 | 32.50 | 309 | ||
| 7 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 170 | 14.17 | |||
| 4 | 4 | 0 | 130 | 32.50 | |||
| 8 | 1 | 48 | 32 | 3 | 0.20 | ||
| 2 | 32 | 16 | 16 | 1.00 | |||
| 3 | 16 | 4 | 170 | 14.17 | |||
| 4 | 4 | 0 | 130 | 32.50 | |||
| 50 | 1 ⁄ 2 | 1 | 50 | 34 | 3 | 0.20 | |
| 2 | 34 | 18 | 16 | 1.00 | |||
| 3 | 18 | 4 | 14 | 1.00 | |||
| 4 | 4 | 0 | 25 | 6.25 | 58 | ||
| 1 | 1 | 50 | 34 | 3 | 0.20 | ||
| 2 | 34 | 18 | 16 | 1.00 | |||
| 3 | 18 | 4 | 40 | 2.86 | |||
| 4 | 4 | 0 | 35 | 8.75 | 94 | ||
| 1 1 ⁄ 2 | 1 | 50 | 34 | 3 | 0.20 | ||
| 2 | 34 | 18 | 16 | 1.00 | |||
| 3 | 18 | 4 | 55 | 3.93 | |||
| 4 | 4 | 0 | 90 | 22.50 | 164 | ||
| 2 | 1 | 50 | 34 | 3 | 0.20 | ||
| 2 | 34 | 18 | 16 | 1.00 | |||
| 3 | 18 | 4 | 70 | 5.00 | |||
| 4 | 4 | 0 | 120 | 30.00 | 209 | ||
| 3 | 1 | 50 | 34 | 3 | 0.20 | ||
| 2 | 34 | 18 | 16 | 1.00 | |||
| 3 | 18 | 4 | 100 | 7.15 | |||
| 4 | 4 | 0 | 130 | 32.50 | 249 | ||
| 4 | 1 | 50 | 34 | 3 | 0.20 | ||
| 2 | 34 | 18 | 16 | 1.00 | |||
| 3 | 18 | 4 | 130 | 8.58 | |||
| 4 | 4 | 0 | 130 | 32.50 | 279 | ||
| 5 | 1 | 50 | 34 | 3 | 0.20 | ||
| 2 | 34 | 18 | 16 | 1.00 | |||
| 3 | 18 | 4 | 160 | 11.42 |
| Working chamber pressure p.s.i.g. | Working period hours | Decompression data | |||
|---|---|---|---|---|---|
| Stage No. | Pressure reduc. p.s.i.g. | Time in stage minutes | Pressure reduc. rate Min/pound | Total time decompress minutes | |
| From | To | ||||
| 4 | 4 | 0 | 130 | 32.50 | 309 |
| 6 | 1 | 50 | 34 | 3 | 0.20 |
| 2 | 34 | 18 | 16 | 1.00 | |
| 3 | 18 | 4 | 180 | 12.85 | |
| 4 | 4 | 0 | 130 | 32.50 | 329 |
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35311, June 30, 1993]
Any openings cut in a floor for the disposal of materials shall be no larger in size than 25 percent of the aggregate of the total floor area, unless the lateral supports of the removed flooring remain in place. Floors weakened or otherwise made unsafe by demolition operations shall be shored to carry safely the intended imposed load from demolition operations.
[44 FR 8577, Feb. 9, 1979, 75 FR 48135, Aug. 9, 2010; 77 FR 49730, Aug. 17, 2012; 78 FR 23843, Apr. 23, 2013]
[44 FR 8577, Feb. 9, 1979, 75 FR 48135, Aug. 9, 2010; 77 FR 49730, Aug. 17, 2012; 78 FR 23843, Apr. 23, 2013]
Selective demolition by explosives shall be conducted in accordance with the applicable sections of subpart U of this part.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35183, June 30, 1993]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35311, June 30, 1993]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 52 FR 36382, Sept. 28, 1987]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35311, June 30, 1993]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35184, June 30, 1993]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 63 FR 33469, June 18, 1998]
Warning Signal
Blast Signal
All Clear Signal
An expendable wire, used in parallel or series, in parallel circuits, to which are connected the leg wires of electric blasting caps.
An insulated expendable wire used between electric blasting caps and the leading wires or between the bus wire and the leading wires.
An insulated wire used between the electric power source and the electric blasting cap circuit.
A permanently mounted insulated wire used between the electric power source and the electric blasting cap circuit.
Department of Transportation is as follows:
Class A Explosives. Possessing detonating hazard, such as dynamite, nitroglycerin, picric acid, lead azide, fulminate of mercury, black powder, blasting caps, and detonating primers.
Class B Explosives. Possessing flammable hazard, such as propellant explosives, including some smokeless propellants.
Class C Explosives. Include certain types of manufactured articles which contain Class A or Class B explosives, or both, as components, but in restricted quantities.
Semiconductive hose—a hose with an electrical resistance high enough to limit flow of stray electric currents to safe levels, yet not so high as to prevent drainage of static electric charges to ground; hose of not more than 2 megohms resistance over its entire length and of not less than 5,000 ohms per foot meets the requirement.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35184, 35311, June 30, 1993]
This subpart applies in addition to all other applicable standards contained in this part 1926. Employers covered under this subpart are not exempt from complying with other applicable provisions in part 1926 by the operation of § 1910.5(c) of this chapter. Specific references in this subpart to other sections of part 1926 are provided for emphasis only.
Each qualified employee shall also be trained and competent in:
The employer shall determine, through regular supervision and through inspections conducted on at least an annual basis, that each employee is complying with the safety-related work practices required by this subpart.
An employee shall receive additional training (or retraining) under any of the following conditions:
The training required by paragraph (b) of this section shall be of the classroom or on-the-job type.
The training shall establish employee proficiency in the work practices required by this subpart and shall introduce the procedures necessary for compliance with this subpart.
The employer shall ensure that each employee has demonstrated proficiency in the work practices involved before that employee is considered as having completed the training required by paragraph (b) of this section.
Before work begins, the host employer shall inform contract employers of:
The contract employer and the host employer shall coordinate their work rules and procedures so that each employee of the contract employer and the host employer is protected as required by this subpart.
Existing characteristics and conditions of electric lines and equipment that are related to the safety of the work to be performed shall be determined before work on or near the lines or equipment is started. Such characteristics and conditions include, but are not limited to:
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 80 FR 60040, Oct. 5, 2015]
The employer shall provide medical services and first aid as required in § 1926.50.
In addition to the requirements of § 1926.50, when employees are performing work on, or associated with, exposed lines or equipment energized at 50 volts or more, persons with first-aid training shall be available as follows:
For field work involving two or more employees at a work location, at least two trained persons shall be available.
For fixed work locations such as substations, the number of trained persons available shall be sufficient to ensure that each employee exposed to electric shock can be reached within 4 minutes by a trained person. However, where the existing number of employees is insufficient to meet this requirement (at a remote substation, for example), each employee at the work location shall be a trained employee.
In assigning an employee or a group of employees to perform a job, the employer shall provide the employee in charge of the job with all available information that relates to the determination of existing characteristics and conditions required by § 1926.950(d).
The employer shall ensure that the employee in charge conducts a job briefing that meets paragraphs (b), (c), and (d) of this section with the employees involved before they start each job.
The briefing shall cover at least the following subjects: Hazards associated with the job, work procedures involved, special precautions, energy-source controls, and personal protective equipment requirements.
If the work or operations to be performed during the work day or shift are repetitive and similar, at least one job briefing shall be conducted before the start of the first job of each day or shift.
Additional job briefings shall be held if significant changes, which might affect the safety of the employees, occur during the course of the work.
A brief discussion is satisfactory if the work involved is routine and if the employees, by virtue of training and experience, can reasonably be expected to recognize and avoid the hazards involved in the job.
A more extensive discussion shall be conducted:
An employee working alone need not conduct a job briefing. However, the employer shall ensure that the tasks to be performed are planned as if a briefing were required.
This section covers enclosed spaces that may be entered by employees. It does not apply to vented vaults if the employer makes a determination that the ventilation system is operating to protect employees before they enter the space. This section applies to routine entry into enclosed spaces. If, after the employer takes the precautions given in this section and in § 1926.965, the hazards remaining in the enclosed space endanger the life of an entrant or could interfere with an entrant's escape from the space, then entry into the enclosed space must meet the permit space entry requirements of subpart AA of this part. For routine entries where the hazards remaining in the enclosed space do not endanger the life of an entrant or interfere with an entrant's escape from the space, this section applies in lieu of the permit-space entry requirements contained in §§ 1926.1204 through 926.1211.
The employer shall ensure the use of safe work practices for entry into, and work in, enclosed spaces and for rescue of employees from such spaces.
Each employee who enters an enclosed space or who serves as an attendant shall be trained in the hazards of enclosed-space entry, in enclosed-space entry procedures, and in enclosed-space rescue procedures.
Employers shall provide equipment to ensure the prompt and safe rescue of employees from the enclosed space.
Before any entrance cover to an enclosed space is removed, the employer shall determine whether it is safe to do so by checking for the presence of any atmospheric pressure or temperature differences and by evaluating whether there might be a hazardous atmosphere in the space. Any conditions making it unsafe to remove the cover shall be eliminated before the cover is removed.
When covers are removed from enclosed spaces, the opening shall be promptly guarded by a railing, temporary cover, or other barrier designed to prevent an accidental fall through the opening and to protect employees working in the space from objects entering the space.
Employees may not enter any enclosed space while it contains a hazardous atmosphere, unless the entry conforms to the confined spaces in construction standard in subpart AA of this part.
While work is being performed in the enclosed space, an attendant with first-aid training shall be immediately available outside the enclosed space to provide assistance if a hazard exists because of traffic patterns in the area of the opening used for entry. The attendant is not precluded from performing other duties outside the enclosed space if these duties do not distract the attendant from: Monitoring employees within the space or ensuring that it is safe for employees to enter and exit the space.
Test instruments used to monitor atmospheres in enclosed spaces shall be kept in calibration and shall have a minimum accuracy of ±10 percent.
Before an employee enters an enclosed space, the atmosphere in the enclosed space shall be tested for oxygen deficiency with a direct-reading meter or similar instrument, capable of collection and immediate analysis of data samples without the need for off-site evaluation. If continuous forced-air ventilation is provided, testing is not required provided that the procedures used ensure that employees are not exposed to the hazards posed by oxygen deficiency.
Before an employee enters an enclosed space, the internal atmosphere shall be tested for flammable gases and vapors with a direct-reading meter or similar instrument capable of collection and immediate analysis of data samples without the need for off-site evaluation. This test shall be performed after the oxygen testing and ventilation required by paragraph (j) of this section demonstrate that there is sufficient oxygen to ensure the accuracy of the test for flammability.
If continuous forced-air ventilation is used, it shall begin before entry is made and shall be maintained long enough for the employer to be able to demonstrate that a safe atmosphere exists before employees are allowed to enter the work area. The forced-air ventilation shall be so directed as to ventilate the immediate area where employees are present within the enclosed space and shall continue until all employees leave the enclosed space.
The air supply for the continuous forced-air ventilation shall be from a clean source and may not increase the hazards in the enclosed space.
If open flames are used in enclosed spaces, a test for flammable gases and vapors shall be made immediately before the open flame device is used and at least once per hour while the device is used in the space. Testing shall be conducted more frequently if conditions present in the enclosed space indicate that once per hour is insufficient to detect hazardous accumulations of flammable gases or vapors.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 80 FR 25518, May 4, 2015]
Personal protective equipment shall meet the requirements of subpart E of this part.
Body belts and positioning straps for work-positioning equipment shall meet the following requirements:
| Test method | Criteria for passing the test |
|---|---|
| Vertically suspend a 500-mm (19.7-inch) length of strapping supporting a 100-kg (220.5-lb) weight | Any flames on the positioning strap shall self extinguish. |
| Use a butane or propane burner with a 76-mm (3-inch) flame | The positioning strap shall continue to support the 100-kg (220.5-lb) mass. |
| Direct the flame to an edge of the strapping at a distance of 25 mm (1 inch). | |
| Remove the flame after 5 seconds. | |
| Wait for any flames on the positioning strap to stop burning. |
Requirements for portable ladders contained in subpart X of this part apply in addition to the requirements of this section, except as specifically noted in paragraph (b) of this section.
Portable ladders used on structures or conductors in conjunction with overhead line work need not meet § 1926.1053(b)(5)(i) and (b)(12). Portable ladders and platforms used on structures or conductors in conjunction with overhead line work shall meet the following requirements:
In the configurations in which they are used, portable platforms shall be capable of supporting without failure at least 2.5 times the maximum intended load.
Portable ladders and platforms may not be loaded in excess of the working loads for which they are designed.
Portable ladders and platforms shall be secured to prevent them from becoming dislodged.
Portable ladders and platforms may be used only in applications for which they are designed.
Portable metal ladders and other portable conductive ladders may not be used near exposed energized lines or equipment. However, in specialized high-voltage work, conductive ladders shall be used when the employer demonstrates that nonconductive ladders would present a greater hazard to employees than conductive ladders.
Paragraph (b) of this section applies to electric equipment connected by cord and plug. Paragraph (c) of this section applies to portable and vehicle-mounted generators used to supply cord- and plug-connected equipment. Paragraph (d) of this section applies to hydraulic and pneumatic tools.
Cord- and plug-connected equipment not covered by subpart K of this part shall comply with one of the following instead of § 1926.302(a)(1):
Portable and vehicle-mounted generators used to supply cord- and plug-connected equipment covered by paragraph (b) of this section shall meet the following requirements:
The generator may only supply equipment located on the generator or the vehicle and cord- and plug-connected equipment through receptacles mounted on the generator or the vehicle.
The non-current-carrying metal parts of equipment and the equipment grounding conductor terminals of the receptacles shall be bonded to the generator frame.
For vehicle-mounted generators, the frame of the generator shall be bonded to the vehicle frame.
Any neutral conductor shall be bonded to the generator frame.
Paragraph (d)(1) of § 1926.302 does not apply to hydraulic fluid used in insulating sections of hydraulic tools.
Safe operating pressures for hydraulic and pneumatic tools, hoses, valves, pipes, filters, and fittings may not be exceeded.
A hydraulic or pneumatic tool used where it may contact exposed energized parts shall be designed and maintained for such use.
The hydraulic system supplying a hydraulic tool used where it may contact exposed live parts shall provide protection against loss of insulating value, for the voltage involved, due to the formation of a partial vacuum in the hydraulic line.
A pneumatic tool used on energized electric lines or equipment, or used where it may contact exposed live parts, shall provide protection against the accumulation of moisture in the air supply.
Pressure shall be released before connections are broken, unless quick-acting, self-closing connectors are used.
Employers must ensure that employees do not use any part of their bodies to locate, or attempt to stop, a hydraulic leak.
Hoses may not be kinked.
Live-line tool rods, tubes, and poles shall be designed and constructed to withstand the following minimum tests:
If the tool is made of fiberglass-reinforced plastic (FRP), it shall withstand 328,100 volts per meter (100,000 volts per foot) of length for 5 minutes, or
If the tool is made of wood, it shall withstand 246,100 volts per meter (75,000 volts per foot) of length for 3 minutes, or
The tool shall withstand other tests that the employer can demonstrate are equivalent.
Each live-line tool shall be wiped clean and visually inspected for defects before use each day.
If any defect or contamination that could adversely affect the insulating qualities or mechanical integrity of the live-line tool is present after wiping, the tool shall be removed from service and examined and tested according to paragraph (b)(3) of this section before being returned to service.
Live-line tools used for primary employee protection shall be removed from service every 2 years, and whenever required under paragraph (b)(2) of this section, for examination, cleaning, repair, and testing as follows:
Materials handling and storage shall comply with applicable material-handling and material-storage requirements in this part, including those in subparts N and CC of this part.
In areas to which access is not restricted to qualified persons only, materials or equipment may not be stored closer to energized lines or exposed energized parts of equipment than the following distances, plus a distance that provides for the maximum sag and side swing of all conductors and for the height and movement of material-handling equipment:
In areas restricted to qualified employees, materials may not be stored within the working space about energized lines or equipment.
Mechanical equipment shall be operated in accordance with applicable requirements in this part, including subparts N, O, and CC of this part, except that § 1926.600(a)(6) does not apply to operations performed by qualified employees.
The critical safety components of mechanical elevating and rotating equipment shall receive a thorough visual inspection before use on each shift.
The operator of an electric line truck may not leave his or her position at the controls while a load is suspended, unless the employer can demonstrate that no employee (including the operator) is endangered.
Mobile equipment, if provided with outriggers, shall be operated with the outriggers extended and firmly set, except as provided in paragraph (b)(3) of this section.
Outriggers may not be extended or retracted outside of the clear view of the operator unless all employees are outside the range of possible equipment motion.
If the work area or the terrain precludes the use of outriggers, the equipment may be operated only within its maximum load ratings specified by the equipment manufacturer for the particular configuration of the equipment without outriggers.
Mechanical equipment used to lift or move lines or other material shall be used within its maximum load rating and other design limitations for the conditions under which the mechanical equipment is being used.
Mechanical equipment shall be operated so that the minimum approach distances, established by the employer under § 1926.960(c)(1)(i), are maintained from exposed energized lines and equipment. However, the insulated portion of an aerial lift operated by a qualified employee in the lift is exempt from this requirement if the applicable minimum approach distance is maintained between the uninsulated portions of the aerial lift and exposed objects having a different electrical potential.
A designated employee other than the equipment operator shall observe the approach distance to exposed lines and equipment and provide timely warnings before the minimum approach distance required by paragraph (d)(1) of this section is reached, unless the employer can demonstrate that the operator can accurately determine that the minimum approach distance is being maintained.
If, during operation of the mechanical equipment, that equipment could become energized, the operation also shall comply with at least one of paragraphs (d)(3)(i) through (d)(3)(iii) of this section.
This section applies to work on exposed live parts, or near enough to them to expose the employee to any hazard they present.
Electric lines and equipment shall be considered and treated as energized unless they have been deenergized in accordance with § 1926.961.
The employer shall ensure that each employee, to the extent that other safety-related conditions at the worksite permit, works in a position from which a slip or shock will not bring the employee's body into contact with exposed, uninsulated parts energized at a potential different from the employee's.
When an employee performs work near exposed parts energized at more than 600 volts, but not more than 72.5 kilovolts, and is not wearing rubber insulating gloves, being protected by insulating equipment covering the energized parts, performing work using live-line tools, or performing live-line barehand work under § 1926.964(c), the employee shall work from a position where he or she cannot reach into the minimum approach distance, established by the employer under paragraph (c)(1) of this section.
The employer shall ensure that employees make connections as follows:
In connecting deenergized equipment or lines to an energized circuit by means of a conducting wire or device, an employee shall first attach the wire to the deenergized part;
When disconnecting equipment or lines from an energized circuit by means of a conducting wire or device, an employee shall remove the source end first; and
When lines or equipment are connected to or disconnected from energized circuits, an employee shall keep loose conductors away from exposed energized parts.
When an employee performs work within reaching distance of exposed energized parts of equipment, the employer shall ensure that the employee removes or renders nonconductive all exposed conductive articles, such as keychains or watch chains, rings, or wrist watches or bands, unless such articles do not increase the hazards associated with contact with the energized parts.
The employer shall assess the workplace to identify employees exposed to hazards from flames or from electric arcs.
For each employee exposed to hazards from electric arcs, the employer shall make a reasonable estimate of the incident heat energy to which the employee would be exposed.
The employer shall ensure that each employee who is exposed to hazards from flames or electric arcs does not wear clothing that could melt onto his or her skin or that could ignite and continue to burn when exposed to flames or the heat energy estimated under paragraph (g)(2) of this section.
The employer shall ensure that the outer layer of clothing worn by an employee, except for clothing not required to be arc rated under paragraphs (g)(5)(i) through (g)(5)(v) of this section, is flame resistant under any of the following conditions:
The employer shall ensure that each employee exposed to hazards from electric arcs wears protective clothing and other protective equipment with an arc rating greater than or equal to the heat energy estimated under paragraph (g)(2) of this section whenever that estimate exceeds 2.0 cal/cm 2. This protective equipment shall cover the employee's entire body, except as follows:
When an employee must install or remove fuses with one or both terminals energized at more than 300 volts, or with exposed parts energized at more than 50 volts, the employer shall ensure that the employee uses tools or gloves rated for the voltage. When an employee installs or removes expulsion-type fuses with one or both terminals energized at more than 300 volts, the employer shall ensure that the employee wears eye protection meeting the requirements of subpart E of this part, uses a tool rated for the voltage, and is clear of the exhaust path of the fuse barrel.
The requirements of this section that pertain to the hazards of exposed live parts also apply when an employee performs work in proximity to covered (noninsulated) wires.
Non-current-carrying metal parts of equipment or devices, such as transformer cases and circuit-breaker housings, shall be treated as energized at the highest voltage to which these parts are exposed, unless the employer inspects the installation and determines that these parts are grounded before employees begin performing the work.
| Nominal voltage (kV) phase-to-phase | Phase-to-ground exposure | Phase-to-phase exposure |
|---|---|---|
| D (m) | D (m) | |
| 5.1 to 15.0 | 0.04 | 0.07 |
| 15.1 to 36.0 | 0.16 | 0.28 |
| 36.1 to 46.0 | 0.23 | 0.37 |
| 46.1 to 72.5 | 0.39 | 0.59 |
| Altitude above sea level (m) | A |
|---|---|
| 0 to 900 | 1.00 |
| 901 to 1,200 | 1.02 |
| 1,201 to 1,500 | 1.05 |
| 1,501 to 1,800 | 1.08 |
| 1,801 to 2,100 | 1.11 |
| 2,101 to 2,400 | 1.14 |
| 2,401 to 2,700 | 1.17 |
| 2,701 to 3,000 | 1.20 |
| 3,001 to 3,600 | 1.25 |
| 3,601 to 4,200 | 1.30 |
| 4,201 to 4,800 | 1.35 |
| 4,801 to 5,400 | 1.39 |
| 5,401 to 6,000 | 1.44 |
| Nominal voltage (kV) phase-to-phase | Distance | |||
|---|---|---|---|---|
| Phase-to-ground exposure | Phase-to-phase exposure | |||
| m | ft | m | ft | |
| 0.050 0.300 2 | Avoid contact | Avoid contact | ||
| 0.301 to 0.750 2 | 0.33 | 1.09 | 0.33 | 1.09 |
| 0.751 to 5.0 | 0.63 | 2.07 | 0.63 | 2.07 |
| 5.1 to 15.0 | 0.65 | 2.14 | 0.68 | 2.24 |
| 15.1 to 36.0 | 0.77 | 2.53 | 0.89 | 2.92 |
| 36.1 to 46.0 | 0.84 | 2.76 | 0.98 | 3.22 |
| 46.1 to 72.5 | 1.00 | 3.29 | 1.20 | 3.94 |
| 1 Employers may use the minimum approach distances in this table provided the worksite is at an elevation of 900 meters (3,000 feet) or less. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table V-4 corresponding to the altitude of the work. | ||||
| 2 For single-phase systems, use voltage-to-ground. |
| Voltage range phase to phase (kV) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 72.6 to 121.0 | 1.13 | 3.71 | 1.42 | 4.66 |
| 121.1 to 145.0 | 1.30 | 4.27 | 1.64 | 5.38 |
| 145.1 to 169.0 | 1.46 | 4.79 | 1.94 | 6.36 |
| 169.1 to 242.0 | 2.01 | 6.59 | 3.08 | 10.10 |
| 242.1 to 362.0 | 3.41 | 11.19 | 5.52 | 18.11 |
| 362.1 to 420.0 | 4.25 | 13.94 | 6.81 | 22.34 |
| 420.1 to 550.0 | 5.07 | 16.63 | 8.24 | 27.03 |
| 550.1 to 800.0 | 6.88 | 22.57 | 11.38 | 37.34 |
| 1 Employers may use the minimum approach distances in this table provided the worksite is at an elevation of 900 meters (3,000 feet) or less. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table V-4 corresponding to the altitude of the work. | ||||
| 2 Employers may use the phase-to-phase minimum approach distances in this table provided that no insulated tool spans the gap and no large conductive object is in the gap. | ||||
| 3 The clear live-line tool distance shall equal or exceed the values for the indicated voltage ranges. |
| Maximum anticipated per-unit transient overvoltage | distance (m) maximum line-to-ground voltage (kV) | ||||
|---|---|---|---|---|---|
| 250 | 400 | 500 | 600 | 750 | |
| 1.5 or less | 1.12 | 1.60 | 2.06 | 2.62 | 3.61 |
| 1.6 | 1.17 | 1.69 | 2.24 | 2.86 | 3.98 |
| 1.7 | 1.23 | 1.82 | 2.42 | 3.12 | 4.37 |
| 1.8 | 1.28 | 1.95 | 2.62 | 3.39 | 4.79 |
| 1 The distances specified in this table are for air, bare-hand, and live-line tool conditions. If employees will be working at elevations greater than 900 meters (3,000 feet) above mean sea level, the employer shall determine minimum approach distances by multiplying the distances in this table by the correction factor in Table V-4 corresponding to the altitude of the work. |
| Voltage range (kV) | Type of current (ac or dc) | Assumed maximum per-unit transient overvoltage |
|---|---|---|
| 72.6 to 420.0 | ac | 3.5 |
| 420.1 to 550.0 | ac | 3.0 |
| 550.1 to 800.0 | ac | 2.5 |
| 250 to 750 | dc | 1.8 |
[79 FR 20696, Apr. 11, 2014, as amended at 79 FR 56962, Sept. 24, 2014; 80 FR 60040, Oct. 5, 2015]
This section applies to the deenergizing of transmission and distribution lines and equipment for the purpose of protecting employees. Conductors and parts of electric equipment that have been deenergized under procedures other than those required by this section shall be treated as energized.
If a system operator is in charge of the lines or equipment and their means of disconnection, the employer shall designate one employee in the crew to be in charge of the clearance and shall comply with all of the requirements of paragraph (c) of this section in the order specified.
If no system operator is in charge of the lines or equipment and their means of disconnection, the employer shall designate one employee in the crew to be in charge of the clearance and to perform the functions that the system operator would otherwise perform under this section. All of the requirements of paragraph (c) of this section apply, in the order specified, except as provided in paragraph (b)(3) of this section.
If two or more crews will be working on the same lines or equipment, then:
The employee that the employer designates pursuant to paragraph (b) of this section as being in charge of the clearance shall make a request of the system operator to deenergize the particular section of line or equipment. The designated employee becomes the employee in charge (as this term is used in paragraph (c) of this section) and is responsible for the clearance.
The employer shall ensure that all switches, disconnectors, jumpers, taps, and other means through which known sources of electric energy may be supplied to the particular lines and equipment to be deenergized are open. The employer shall render such means inoperable, unless its design does not so permit, and then ensure that such means are tagged to indicate that employees are at work.
The employer shall ensure that automatically and remotely controlled switches that could cause the opened disconnecting means to close are also tagged at the points of control. The employer shall render the automatic or remote control feature inoperable, unless its design does not so permit.
The employer need not use the tags mentioned in paragraphs (c)(2) and (c)(3) of this section on a network protector for work on the primary feeder for the network protector's associated network transformer when the employer can demonstrate all of the following conditions:
Tags shall prohibit operation of the disconnecting means and shall indicate that employees are at work.
After the applicable requirements in paragraphs (c)(1) through (c)(5) of this section have been followed and the system operator gives a clearance to the employee in charge, the employer shall ensure that the lines and equipment are deenergized by testing the lines and equipment to be worked with a device designed to detect voltage.
The employer shall ensure the installation of protective grounds as required by § 1926.962.
After the applicable requirements of paragraphs (c)(1) through (c)(7) of this section have been followed, the lines and equipment involved may be considered deenergized.
To transfer the clearance, the employee in charge (or the employee's supervisor if the employee in charge must leave the worksite due to illness or other emergency) shall inform the system operator and employees in the crew; and the new employee in charge shall be responsible for the clearance.
To release a clearance, the employee in charge shall:
Only the employee in charge who requested the clearance may release the clearance, unless the employer transfers responsibility under paragraph (c)(9) of this section.
No one may remove tags without the release of the associated clearance as specified under paragraphs (c)(10) and (c)(11) of this section.
The employer shall ensure that no one initiates action to reenergize the lines or equipment at a point of disconnection until all protective grounds have been removed, all crews working on the lines or equipment release their clearances, all employees are clear of the lines and equipment, and all protective tags are removed from that point of disconnection.
This section applies to grounding of transmission and distribution lines and equipment for the purpose of protecting employees. Paragraph (d) of this section also applies to protective grounding of other equipment as required elsewhere in this Subpart.
For any employee to work transmission and distribution lines or equipment as deenergized, the employer shall ensure that the lines or equipment are deenergized under the provisions of § 1926.961 and shall ensure proper grounding of the lines or equipment as specified in paragraphs (c) through (h) of this section. However, if the employer can demonstrate that installation of a ground is impracticable or that the conditions resulting from the installation of a ground would present greater hazards to employees than working without grounds, the lines and equipment may be treated as deenergized provided that the employer establishes that all of the following conditions apply:
The employer ensures that the lines and equipment are deenergized under the provisions of § 1926.961.
There is no possibility of contact with another energized source.
The hazard of induced voltage is not present.
Temporary protective grounds shall be placed at such locations and arranged in such a manner that the employer can demonstrate will prevent each employee from being exposed to hazardous differences in electric potential.
Protective grounds shall have an impedance low enough so that they do not delay the operation of protective devices in case of accidental energizing of the lines or equipment.
The employer shall ensure that, unless a previously installed ground is present, employees test lines and equipment and verify the absence of nominal voltage before employees install any ground on those lines or that equipment.
The employer shall ensure that, when an employee attaches a ground to a line or to equipment, the employee attaches the ground-end connection first and then attaches the other end by means of a live-line tool. For lines or equipment operating at 600 volts or less, the employer may permit the employee to use insulating equipment other than a live-line tool if the employer ensures that the line or equipment is not energized at the time the ground is connected or if the employer can demonstrate that each employee is protected from hazards that may develop if the line or equipment is energized.
The employer shall ensure that, when an employee removes a ground, the employee removes the grounding device from the line or equipment using a live-line tool before he or she removes the ground-end connection. For lines or equipment operating at 600 volts or less, the employer may permit the employee to use insulating equipment other than a live-line tool if the employer ensures that the line or equipment is not energized at the time the ground is disconnected or if the employer can demonstrate that each employee is protected from hazards that may develop if the line or equipment is energized.
The employer shall ensure that, when an employee performs work on a cable at a location remote from the cable terminal, the cable is not grounded at the cable terminal if there is a possibility of hazardous transfer of potential should a fault occur.
The employer may permit employees to remove grounds temporarily during tests. During the test procedure, the employer shall ensure that each employee uses insulating equipment, shall isolate each employee from any hazards involved, and shall implement any additional measures necessary to protect each exposed employee in case the previously grounded lines and equipment become energized.
This section provides for safe work practices for high-voltage and high-power testing performed in laboratories, shops, and substations, and in the field and on electric transmission and distribution lines and equipment. It applies only to testing involving interim measurements using high voltage, high power, or combinations of high voltage and high power, and not to testing involving continuous measurements as in routine metering, relaying, and normal line work.
The employer shall establish and enforce work practices for the protection of each worker from the hazards of high-voltage or high-power testing at all test areas, temporary and permanent. Such work practices shall include, as a minimum, test area safeguarding, grounding, the safe use of measuring and control circuits, and a means providing for periodic safety checks of field test areas.
The employer shall ensure that each employee, upon initial assignment to the test area, receives training in safe work practices, with retraining provided as required by § 1926.950(b).
The employer shall provide safeguarding within test areas to control access to test equipment or to apparatus under test that could become energized as part of the testing by either direct or inductive coupling and to prevent accidental employee contact with energized parts.
The employer shall guard permanent test areas with walls, fences, or other barriers designed to keep employees out of the test areas.
In field testing, or at a temporary test site not guarded by permanent fences and gates, the employer shall ensure the use of one of the following means to prevent employees without authorization from entering:
The employer shall ensure the removal of the safeguards required by paragraph (c)(3) of this section when employees no longer need the protection afforded by the safeguards.
The employer shall establish and implement safe grounding practices for the test facility.
The employer shall ensure either that visible grounds are applied automatically, or that employees using properly insulated tools manually apply visible grounds, to the high-voltage circuits after they are deenergized and before any employee performs work on the circuit or on the item or apparatus under test. Common ground connections shall be solidly connected to the test equipment and the apparatus under test.
In high-power testing, the employer shall provide an isolated ground-return conductor system designed to prevent the intentional passage of current, with its attendant voltage rise, from occurring in the ground grid or in the earth. However, the employer need not provide an isolated ground-return conductor if the employer can demonstrate that both of the following conditions exist:
For tests in which using the equipment grounding conductor in the equipment power cord to ground the test equipment would result in greater hazards to test personnel or prevent the taking of satisfactory measurements, the employer may use a ground clearly indicated in the test set-up if the employer can demonstrate that this ground affords protection for employees equivalent to the protection afforded by an equipment grounding conductor in the power supply cord.
The employer shall ensure that, when any employee enters the test area after equipment is deenergized, a ground is placed on the high-voltage terminal and any other exposed terminals.
If the employer uses a test trailer or test vehicle in field testing, its chassis shall be grounded. The employer shall protect each employee against hazardous touch potentials with respect to the vehicle, instrument panels, and other conductive parts accessible to employees with bonding, insulation, or isolation.
The employer may not run control wiring, meter connections, test leads, or cables from a test area unless contained in a grounded metallic sheath and terminated in a grounded metallic enclosure or unless the employer takes other precautions that it can demonstrate will provide employees with equivalent safety.
The employer shall isolate meters and other instruments with accessible terminals or parts from test personnel to protect against hazards that could arise should such terminals and parts become energized during testing. If the employer provides this isolation by locating test equipment in metal compartments with viewing windows, the employer shall provide interlocks to interrupt the power supply when someone opens the compartment cover.
The employer shall protect temporary wiring and its connections against damage, accidental interruptions, and other hazards. To the maximum extent possible, the employer shall keep signal, control, ground, and power cables separate from each other.
If any employee will be present in the test area during testing, a test observer shall be present. The test observer shall be capable of implementing the immediate deenergizing of test circuits for safety purposes.
Safety practices governing employee work at temporary or field test areas shall provide, at the beginning of each series of tests, for a routine safety check of such test areas.
The test operator in charge shall conduct these routine safety checks before each series of tests and shall verify at least the following conditions:
This section provides additional requirements for work performed on or near overhead lines and equipment and for live-line barehand work.
Before allowing employees to subject elevated structures, such as poles or towers, to such stresses as climbing or the installation or removal of equipment may impose, the employer shall ascertain that the structures are capable of sustaining the additional or unbalanced stresses. If the pole or other structure cannot withstand the expected loads, the employer shall brace or otherwise support the pole or structure so as to prevent failure.
The following provisions apply to the installation and removal of overhead conductors or cable (overhead lines).
When lines that employees are installing or removing can contact energized parts, the employer shall use the tension-stringing method, barriers, or other equivalent measures to minimize the possibility that conductors and cables the employees are installing or removing will contact energized power lines or equipment.
If the conductors that employees are installing or removing cross over energized conductors in excess of 600 volts and if the design of the circuit-interrupting devices protecting the lines so permits, the employer shall render inoperable the automatic-reclosing feature of these devices.
Reel-handling equipment, including pulling and tensioning devices, shall be in safe operating condition and shall be leveled and aligned.
The employer shall ensure that employees do not exceed load ratings of stringing lines, pulling lines, conductor grips, load-bearing hardware and accessories, rigging, and hoists.
The employer shall repair or replace defective pulling lines and accessories.
The employer shall ensure that employees do not use conductor grips on wire rope unless the manufacturer specifically designed the grip for this application.
The employer shall ensure that employees maintain reliable communications, through two-way radios or other equivalent means, between the reel tender and the pulling-rig operator.
Employees may operate the pulling rig only when it is safe to do so.
In addition to other applicable provisions contained in this subpart, the following requirements apply to live-line barehand work:
Before an employee uses or supervises the use of the live-line barehand technique on energized circuits, the employer shall ensure that the employee completes training conforming to § 1926.950(b) in the technique and in the safety requirements of paragraph (c) of this section.
Before any employee uses the live-line barehand technique on energized high-voltage conductors or parts, the employer shall ascertain the following information in addition to information about other existing conditions required by § 1926.950(d):
The employer shall render inoperable the automatic-reclosing feature of circuit-interrupting devices protecting the lines if the design of the devices permits.
The employer shall ensure that employees do not perform work when adverse weather conditions would make the work hazardous even after the employer implements the work practices required by this subpart. Additionally, employees may not perform work when winds reduce the phase-to-phase or phase-to-ground clearances at the work location below the minimum approach distances specified in paragraph (c)(13) of this section, unless insulating guards cover the grounded objects and other lines and equipment.
The employer shall provide and ensure that employees use a conductive bucket liner or other conductive device for bonding the insulated aerial device to the energized line or equipment.
The employer shall ensure that, before the employee contacts the energized part, the employee bonds the conductive bucket liner or other conductive device to the energized conductor by means of a positive connection. This connection shall remain attached to the energized conductor until the employee completes the work on the energized circuit.
Aerial lifts used for live-line barehand work shall have dual controls (lower and upper) as follows:
Lower (ground-level) lift controls may not be operated with an employee in the lift except in case of emergency.
The employer shall ensure that, before employees elevate an aerial lift into the work position, the employees check all controls (ground level and bucket) to determine that they are in proper working condition.
The employer shall ensure that, before employees elevate the boom of an aerial lift, the employees ground the body of the truck or barricade the body of the truck and treat it as energized.
The employer shall ensure that employees perform a boom-current test before starting work each day, each time during the day when they encounter a higher voltage, and when changed conditions indicate a need for an additional test.
The employer shall ensure that employees maintain the minimum approach distances, established by the employer under § 1926.960(c)(1)(i), from all grounded objects and from lines and equipment at a potential different from that to which the live-line barehand equipment is bonded, unless insulating guards cover such grounded objects and other lines and equipment.
While the bucket is alongside an energized bushing or insulator string, the employer shall ensure that employees maintain the phase-to-ground minimum approach distances, established by the employer under § 1926.960(c)(1)(i), between all parts of the bucket and the grounded end of the bushing or insulator string or any other grounded surface.
The employer shall ensure that employees do not use handlines between the bucket and the boom or between the bucket and the ground. However, employees may use nonconductive-type handlines from conductor to ground if not supported from the bucket. The employer shall ensure that no one uses ropes used for live-line barehand work for other purposes.
The employer shall ensure that employees do not pass uninsulated equipment or material between a pole or structure and an aerial lift while an employee working from the bucket is bonded to an energized part.
A nonconductive measuring device shall be readily accessible to employees performing live-line barehand work to assist them in maintaining the required minimum approach distance.
The following requirements apply to work performed on towers or other structures that support overhead lines.
The employer shall ensure that no employee is under a tower or structure while work is in progress, except when the employer can demonstrate that such a working position is necessary to assist employees working above.
The employer shall ensure that employees use tag lines or other similar devices to maintain control of tower sections being raised or positioned, unless the employer can demonstrate that the use of such devices would create a greater hazard to employees.
The employer shall ensure that employees do not detach the loadline from a member or section until they safely secure the load.
The employer shall ensure that, except during emergency restoration procedures, employees discontinue work when adverse weather conditions would make the work hazardous in spite of the work practices required by this subpart.
This section provides additional requirements for work on underground electrical installations.
The employer shall ensure that employees use a ladder or other climbing device to enter and exit a manhole or subsurface vault exceeding 1.22 meters (4 feet) in depth. No employee may climb into or out of a manhole or vault by stepping on cables or hangers.
Equipment used to lower materials and tools into manholes or vaults shall be capable of supporting the weight to be lowered and shall be checked for defects before use.
Before anyone lowers tools or material into the opening for a manhole or vault, each employee working in the manhole or vault shall be clear of the area directly under the opening.
While work is being performed in a manhole or vault containing energized electric equipment, an employee with first-aid training shall be available on the surface in the immediate vicinity of the manhole or vault entrance to render emergency assistance.
Occasionally, the employee on the surface may briefly enter a manhole or vault to provide nonemergency assistance.
For the purpose of inspection, housekeeping, taking readings, or similar work, an employee working alone may enter, for brief periods of time, a manhole or vault where energized cables or equipment are in service if the employer can demonstrate that the employee will be protected from all electrical hazards.
The employer shall ensure that employees maintain reliable communications, through two-way radios or other equivalent means, among all employees involved in the job.
The employer shall ensure that, if employees use duct rods, the employees install the duct rods in the direction presenting the least hazard to employees. The employer shall station an employee at the far end of the duct line being rodded to ensure that the employees maintain the required minimum approach distances.
When multiple cables are present in a work area, the employer shall identify the cable to be worked by electrical means, unless its identity is obvious by reason of distinctive appearance or location or by other readily apparent means of identification. The employer shall protect cables other than the one being worked from damage.
Except when paragraph (h)(2) of this section permits employees to perform work that could cause a fault in an energized cable in a manhole or vault, the employer shall ensure that employees inspect energized cables to be moved for abnormalities.
Where a cable in a manhole or vault has one or more abnormalities that could lead to a fault or be an indication of an impending fault, the employer shall deenergize the cable with the abnormality before any employee may work in the manhole or vault, except when service-load conditions and a lack of feasible alternatives require that the cable remain energized. In that case, employees may enter the manhole or vault provided the employer protects them from the possible effects of a failure using shields or other devices that are capable of containing the adverse effects of a fault. The employer shall treat the following abnormalities as indications of impending faults unless the employer can demonstrate that the conditions could not lead to a fault: Oil or compound leaking from cable or joints, broken cable sheaths or joint sleeves, hot localized surface temperatures of cables or joints, or joints swollen beyond normal tolerance.
If the work employees will perform in a manhole or vault could cause a fault in a cable, the employer shall deenergize that cable before any employee works in the manhole or vault, except when service-load conditions and a lack of feasible alternatives require that the cable remain energized. In that case, employees may enter the manhole or vault provided the employer protects them from the possible effects of a failure using shields or other devices that are capable of containing the adverse effects of a fault.
When employees perform work on buried cable or on cable in a manhole or vault, the employer shall maintain metallic-sheath continuity, or the cable sheath shall be treated as energized.
This section provides additional requirements for substations and for work performed in them.
The employer shall provide and maintain sufficient access and working space about electric equipment to permit ready and safe operation and maintenance of such equipment by employees.
The employer shall ensure that, when employees remove or insert draw-out-type circuit breakers, the breaker is in the open position. The employer shall also render the control circuit inoperable if the design of the equipment permits.
Conductive fences around substations shall be grounded. When a substation fence is expanded or a section is removed, fence sections shall be isolated, grounded, or bonded as necessary to protect employees from hazardous differences in electric potential.
Rooms and other spaces in which electric supply lines or equipment are installed shall meet the requirements of paragraphs (e)(2) through (e)(5) of this section under the following conditions:
Fences, screens, partitions, or walls shall enclose the rooms and other spaces so as to minimize the possibility that unqualified persons will enter.
Unqualified persons may not enter the rooms or other spaces while the electric supply lines or equipment are energized.
The employer shall display signs at entrances to the rooms and other spaces warning unqualified persons to keep out.
The employer shall keep each entrance to a room or other space locked, unless the entrance is under the observation of a person who is attending the room or other space for the purpose of preventing unqualified employees from entering.
The employer shall provide guards around all live parts operating at more than 150 volts to ground without an insulating covering unless the location of the live parts gives sufficient clearance (horizontal, vertical, or both) to minimize the possibility of accidental employee contact.
Except for fuse replacement and other necessary access by qualified persons, the employer shall maintain guarding of energized parts within a compartment during operation and maintenance functions to prevent accidental contact with energized parts and to prevent dropped tools or other equipment from contacting energized parts.
Before guards are removed from energized equipment, the employer shall install barriers around the work area to prevent employees who are not working on the equipment, but who are in the area, from contacting the exposed live parts.
Upon entering an attended substation, each employee, other than employees regularly working in the station, shall report his or her presence to the employee in charge of substation activities to receive information on special system conditions affecting employee safety.
The job briefing required by § 1926.952 shall cover information on special system conditions affecting employee safety, including the location of energized equipment in or adjacent to the work area and the limits of any deenergized work area.
The following additional requirements apply to work on capacitors and on lines connected to capacitors.
Before employees work on capacitors, the employer shall disconnect the capacitors from energized sources and short circuit the capacitors. The employer shall ensure that the employee short circuiting the capacitors waits at least 5 minutes from the time of disconnection before applying the short circuit,
Before employees handle the units, the employer shall short circuit each unit in series-parallel capacitor banks between all terminals and the capacitor case or its rack. If the cases of capacitors are on ungrounded substation racks, the employer shall bond the racks to ground.
The employer shall short circuit any line connected to capacitors before the line is treated as deenergized.
The employer shall ensure that employees do not open the secondary of a current transformer while the transformer is energized. If the employer cannot deenergize the primary of the current transformer before employees perform work on an instrument, a relay, or other section of a current transformer secondary circuit, the employer shall bridge the circuit so that the current transformer secondary does not experience an open-circuit condition.
If the open-circuit voltage exceeds 600 volts, the employer shall ensure that employees work on series streetlighting circuits in accordance with § 1926.964 or § 1926.965, as appropriate.
Before any employee opens a series loop, the employer shall deenergize the streetlighting transformer and isolate it from the source of supply or shall bridge the loop to avoid an open-circuit condition.
The employer shall provide sufficient illumination to enable the employee to perform the work safely.
Whenever an employee may be pulled or pushed, or might fall, into water where the danger of drowning exists, the employer shall provide the employee with, and shall ensure that the employee uses, a personal flotation device meeting § 1926.106.
The employer shall maintain each personal flotation device in safe condition and shall inspect each personal flotation device frequently enough to ensure that it does not have rot, mildew, water saturation, or any other condition that could render the device unsuitable for use.
An employee may cross streams or other bodies of water only if a safe means of passage, such as a bridge, is available.
Excavation operations shall comply with subpart P of this part.
Traffic-control signs and traffic-control devices used for the protection of employees shall meet § 1926.200(g)(2).
Before employees begin work in the vicinity of vehicular or pedestrian traffic that may endanger them, the employer shall place warning signs or flags and other traffic-control devices in conspicuous locations to alert and channel approaching traffic.
The employer shall use barricades where additional employee protection is necessary.
The employer shall protect excavated areas with barricades.
The employer shall display warning lights prominently at night.
When there is a possibility of voltage backfeed from sources of cogeneration or from the secondary system (for example, backfeed from more than one energized phase feeding a common load), the requirements of § 1926.960 apply if employees will work the lines or equipment as energized, and the requirements of §§ 1926.961 and 1926.962 apply if employees will work the lines or equipment as deenergized.
The employer shall install, adjust, and operate laser equipment in accordance with § 1926.54.
Hydraulic fluids used for the insulated sections of equipment shall provide insulation for the voltage involved.
The employer shall ensure that employees perform power-line carrier work, including work on equipment used for coupling carrier current to power line conductors, in accordance with the requirements of this subpart pertaining to work on energized lines.
Attendant. An employee assigned to remain immediately outside the entrance to an enclosed or other space to render assistance as needed to employees inside the space.
Automatic circuit recloser. A self-controlled device for automatically interrupting and reclosing an alternating-current circuit, with a predetermined sequence of opening and reclosing followed by resetting, hold closed, or lockout.
Barricade. A physical obstruction such as tapes, cones, or A-frame type wood or metal structures that provides a warning about, and limits access to, a hazardous area.
Barrier. A physical obstruction that prevents contact with energized lines or equipment or prevents unauthorized access to a work area.
Bond. The electrical interconnection of conductive parts designed to maintain a common electric potential.
Bus. A conductor or a group of conductors that serve as a common connection for two or more circuits.
Bushing. An insulating structure that includes a through conductor or that provides a passageway for such a conductor, and that, when mounted on a barrier, insulates the conductor from the barrier for the purpose of conducting current from one side of the barrier to the other.
Cable. A conductor with insulation, or a stranded conductor with or without insulation and other coverings (single-conductor cable), or a combination of conductors insulated from one another (multiple-conductor cable).
Cable sheath. A conductive protective covering applied to cables.
Circuit. A conductor or system of conductors through which an electric current is intended to flow.
Clearance (between objects). The clear distance between two objects measured surface to surface.
Clearance (for work). Authorization to perform specified work or permission to enter a restricted area.
Communication lines. (See Lines; (1) Communication lines. )
Conductor. A material, usually in the form of a wire, cable, or bus bar, used for carrying an electric current.
Contract employer. An employer, other than a host employer, that performs work covered by subpart V of this part under contract.
Covered conductor. A conductor covered with a dielectric having no rated insulating strength or having a rated insulating strength less than the voltage of the circuit in which the conductor is used.
Current-carrying part. A conducting part intended to be connected in an electric circuit to a source of voltage. Non-current-carrying parts are those not intended to be so connected.
Deenergized. Free from any electrical connection to a source of potential difference and from electric charge; not having a potential that is different from the potential of the earth.
Designated employee (designated person). An employee (or person) who is assigned by the employer to perform specific duties under the terms of this subpart and who has sufficient knowledge of the construction and operation of the equipment, and the hazards involved, to perform his or her duties safely.
Electric line truck. A truck used to transport personnel, tools, and material for electric supply line work.
Electric supply equipment. Equipment that produces, modifies, regulates, controls, or safeguards a supply of electric energy.
Electric supply lines. (See “Lines; (2) Electric supply lines.”)
Electric utility. An organization responsible for the installation, operation, or maintenance of an electric supply system.
Enclosed space. A working space, such as a manhole, vault, tunnel, or shaft, that has a limited means of egress or entry, that is designed for periodic employee entry under normal operating conditions, and that, under normal conditions, does not contain a hazardous atmosphere, but may contain a hazardous atmosphere under abnormal conditions.
Energized (alive, live). Electrically connected to a source of potential difference, or electrically charged so as to have a potential significantly different from that of earth in the vicinity.
Energy source. Any electrical, mechanical, hydraulic, pneumatic, chemical, nuclear, thermal, or other energy source that could cause injury to employees.
Entry (as used in § 1926.953). The action by which a person passes through an opening into an enclosed space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant's body breaks the plane of an opening into the space.
Equipment (electric). A general term including material, fittings, devices, appliances, fixtures, apparatus, and the like used as part of or in connection with an electrical installation.
Exposed, Exposed to contact (as applied to energized parts). Not isolated or guarded.
Fall restraint system. A fall protection system that prevents the user from falling any distance.
First-aid training. Training in the initial care, including cardiopulmonary resuscitation (which includes chest compressions, rescue breathing, and, as appropriate, other heart and lung resuscitation techniques), performed by a person who is not a medical practitioner, of a sick or injured person until definitive medical treatment can be administered.
Ground. A conducting connection, whether planned or unplanned, between an electric circuit or equipment and the earth, or to some conducting body that serves in place of the earth.
Grounded. Connected to earth or to some conducting body that serves in place of the earth.
Guarded. Covered, fenced, enclosed, or otherwise protected, by means of suitable covers or casings, barrier rails or screens, mats, or platforms, designed to minimize the possibility, under normal conditions, of dangerous approach or inadvertent contact by persons or objects.
Hazardous atmosphere. An atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue (that is, escape unaided from an enclosed space), injury, or acute illness from one or more of the following causes:
High-power tests. Tests in which the employer uses fault currents, load currents, magnetizing currents, and line-dropping currents to test equipment, either at the equipment's rated voltage or at lower voltages.
High-voltage tests. Tests in which the employer uses voltages of approximately 1,000 volts as a practical minimum and in which the voltage source has sufficient energy to cause injury.
High wind. A wind of such velocity that one or more of the following hazards would be present:
Host employer. An employer that operates, or that controls the operating procedures for, an electric power generation, transmission, or distribution installation on which a contract employer is performing work covered by subpart V of this part.
Immediately dangerous to life or health (IDLH). Any condition that poses an immediate or delayed threat to life or that would cause irreversible adverse health effects or that would interfere with an individual's ability to escape unaided from a permit space.
Insulated. Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current.
Insulation (cable). Material relied upon to insulate the conductor from other conductors or conducting parts or from ground.
Isolated. Not readily accessible to persons unless special means for access are used.
Line-clearance tree trimming. The pruning, trimming, repairing, maintaining, removing, or clearing of trees, or the cutting of brush, that is within the following distance of electric supply lines and equipment:
Lines —
The conductors and their supporting or containing structures which are used for public or private signal or communication service, and which operate at potentials not exceeding 400 volts to ground or 750 volts between any two points of the circuit, and the transmitted power of which does not exceed 150 watts. If the lines are operating at less than 150 volts, no limit is placed on the transmitted power of the system. Under certain conditions, communication cables may include communication circuits exceeding these limitations where such circuits are also used to supply power solely to communication equipment.
Conductors used to transmit electric energy and their necessary supporting or containing structures. Signal lines of more than 400 volts are always supply lines within this subpart, and those of less than 400 volts are considered as supply lines, if so run and operated throughout.
Manhole. A subsurface enclosure that personnel may enter and that is used for installing, operating, and maintaining submersible equipment or cable.
Minimum approach distance. The closest distance an employee may approach an energized or a grounded object.
Personal fall arrest system. A system used to arrest an employee in a fall from a working level.
Qualified employee (qualified person). An employee (person) knowledgeable in the construction and operation of the electric power generation, transmission, and distribution equipment involved, along with the associated hazards.
Statistical sparkover voltage. A transient overvoltage level that produces a 97.72-percent probability of sparkover (that is, two standard deviations above the voltage at which there is a 50-percent probability of sparkover).
Statistical withstand voltage. A transient overvoltage level that produces a 0.14-percent probability of sparkover (that is, three standard deviations below the voltage at which there is a 50-percent probability of sparkover).
Switch. A device for opening and closing or for changing the connection of a circuit. In this subpart, a switch is manually operable, unless otherwise stated.
System operator. A qualified person designated to operate the system or its parts.
Vault. An enclosure, above or below ground, that personnel may enter and that is used for installing, operating, or maintaining equipment or cable.
Vented vault. A vault that has provision for air changes using exhaust-flue stacks and low-level air intakes operating on pressure and temperature differentials that provide for airflow that precludes a hazardous atmosphere from developing.
Voltage. The effective (root mean square, or rms) potential difference between any two conductors or between a conductor and ground. This subpart expresses voltages in nominal values, unless otherwise indicated. The nominal voltage of a system or circuit is the value assigned to a system or circuit of a given voltage class for the purpose of convenient designation. The operating voltage of the system may vary above or below this value.
Work-positioning equipment. A body belt or body harness system rigged to allow an employee to be supported on an elevated vertical surface, such as a utility pole or tower leg, and work with both hands free while leaning.
[79 FR 20696, Apr. 11, 2014, as amended at 79 FR 56962, Sept. 24, 2014; 80 FR 25518, May 4, 2015; 85 FR 8745, Feb. 18, 2020]
I. Introduction
Electric utilities design electric power generation, transmission, and distribution installations to meet National Electrical Safety Code (NESC), ANSI C2, requirements. Electric utilities also design transmission and distribution lines to limit line outages as required by system reliability criteria 1 and to withstand the maximum overvoltages impressed on the system. Conditions such as switching surges, faults, and lightning can cause overvoltages. Electric utilities generally select insulator design and lengths and the clearances to structural parts so as to prevent outages from contaminated line insulation and during storms. Line insulator lengths and structural clearances have, over the years, come closer to the minimum approach distances used by workers. As minimum approach distances and structural clearances converge, it is increasingly important that system designers and system operating and maintenance personnel understand the concepts underlying minimum approach distances.
1 Federal, State, and local regulatory bodies and electric utilities set reliability requirements that limit the number and duration of system outages.
The information in this appendix will assist employers in complying with the minimum approach-distance requirements contained in §§ 1926.960(c)(1) and 1926.964(c). Employers must use the technical criteria and methodology presented in this appendix in establishing minimum approach distances in accordance with § 1926.960(c)(1)(i) and Table V-2 and Table V-7. This appendix provides essential background information and technical criteria for the calculation of the required minimum approach distances for live-line work on electric power generation, transmission, and distribution installations.
Unless an employer is using the maximum transient overvoltages specified in Table V-8 for voltages over 72.5 kilovolts, the employer must use persons knowledgeable in the techniques discussed in this appendix, and competent in the field of electric transmission and distribution system design, to determine the maximum transient overvoltage.
II. General
A. Definitions. The following definitions from § 1926.968 relate to work on or near electric power generation, transmission, and distribution lines and equipment and the electrical hazards they present.
Exposed.... Not isolated or guarded.
Guarded. Covered, fenced, enclosed, or otherwise protected, by means of suitable covers or casings, barrier rails or screens, mats, or platforms, designed to minimize the possibility, under normal conditions, of dangerous approach or inadvertent contact by persons or objects.
Insulated. Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current.
Isolated. Not readily accessible to persons unless special means for access are used.
Statistical sparkover voltage. A transient overvoltage level that produces a 97.72-percent probability of sparkover (that is, two standard deviations above the voltage at which there is a 50-percent probability of sparkover).
Statistical withstand voltage. A transient overvoltage level that produces a 0.14-percent probability of sparkover (that is, three standard deviations below the voltage at which there is a 50-percent probability of sparkover).
B. Installations energized at 50 to 300 volts. The hazards posed by installations energized at 50 to 300 volts are the same as those found in many other workplaces. That is not to say that there is no hazard, but the complexity of electrical protection required does not compare to that required for high-voltage systems. The employee must avoid contact with the exposed parts, and the protective equipment used (such as rubber insulating gloves) must provide insulation for the voltages involved.
C. Exposed energized parts over 300 volts AC. Paragraph (c)(1)(i) of § 1926.960 requires the employer to establish minimum approach distances no less than the distances computed by Table V-2 for ac systems so that employees can work safely without risk of sparkover. 2
2 Sparkover is a disruptive electric discharge in which an electric arc forms and electric current passes through air.
Unless the employee is using electrical protective equipment, air is the insulating medium between the employee and energized parts. The distance between the employee and an energized part must be sufficient for the air to withstand the maximum transient overvoltage that can reach the worksite under the working conditions and practices the employee is using. This distance is the minimum air insulation distance, and it is equal to the electrical component of the minimum approach distance.
Normal system design may provide or include a means (such as lightning arrestors) to control maximum anticipated transient overvoltages, or the employer may use temporary devices (portable protective gaps) or measures (such as preventing automatic circuit breaker reclosing) to achieve the same result. Paragraph (c)(1)(ii) of § 1926.960 requires the employer to determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis or assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table V-8, which specifies the following maximums for ac systems:
| 72.6 to 420.0 kilovolts | 3.5 per unit. |
|---|---|
| 420.1 to 550.0 kilovolts | 3.0 per unit. |
| 550.1 to 800.0 kilovolts | 2.5 per unit. |
See paragraph IV.A.2, later in this appendix, for additional discussion of maximum transient overvoltages.
D. Types of exposures. Employees working on or near energized electric power generation, transmission, and distribution systems face two kinds of exposures: Phase-to-ground and phase-to-phase. The exposure is phase-to-ground: (1) With respect to an energized part, when the employee is at ground potential or (2) with respect to ground, when an employee is at the potential of the energized part during live-line barehand work. The exposure is phase-to-phase, with respect to an energized part, when an employee is at the potential of another energized part (at a different potential) during live-line barehand work.
III. Determination of Minimum Approach Distances for AC Voltages Greater Than 300 Volts
A. Voltages of 301 to 5,000 volts. Test data generally forms the basis of minimum air insulation distances. The lowest voltage for which sufficient test data exists is 5,000 volts, and these data indicate that the minimum air insulation distance at that voltage is 20 millimeters (1 inch). Because the minimum air insulation distance increases with increasing voltage, and, conversely, decreases with decreasing voltage, an assumed minimum air insulation distance of 20 millimeters will protect against sparkover at voltages of 301 to 5,000 volts. Thus, 20 millimeters is the electrical component of the minimum approach distance for these voltages.
B. Voltages of 5.1 to 72.5 kilovolts. For voltages from 5.1 to 72.5 kilovolts, the Occupational Safety and Health Administration bases the methodology for calculating the electrical component of the minimum approach distance on Institute of Electrical and Electronic Engineers (IEEE) Standard 4-1995, Standard Techniques for High-Voltage Testing. Table 1 lists the critical sparkover distances from that standard as listed in IEEE Std 516-2009, IEEE Guide for Maintenance Methods on Energized Power Lines.
| 60 Hz rod-to-rod sparkover (kV peak) | Gap spacing from IEEE Std 4-1995 (cm) |
|---|---|
| 25 | 2 |
| 36 | 3 |
| 46 | 4 |
| 53 | 5 |
| 60 | 6 |
| 70 | 8 |
| 79 | 10 |
| 86 | 12 |
| 95 | 14 |
| 104 | 16 |
| 112 | 18 |
| 120 | 20 |
| 143 | 25 |
| 167 | 30 |
| 192 | 35 |
| 218 | 40 |
| 243 | 45 |
| 270 | 50 |
| 322 | 60 |
| Source: IEEE Std 516-2009. |
To use this table to determine the electrical component of the minimum approach distance, the employer must determine the peak phase-to-ground transient overvoltage and select a gap from the table that corresponds to that voltage as a withstand voltage rather than a critical sparkover voltage. To calculate the electrical component of the minimum approach distance for voltages between 5 and 72.5 kilovolts, use the following procedure:
1. Divide the phase-to-phase voltage by the square root of 3 to convert it to a phase-to-ground voltage.
2. Multiply the phase-to-ground voltage by the square root of 2 to convert the rms value of the voltage to the peak phase-to-ground voltage.
3. Multiply the peak phase-to-ground voltage by the maximum per-unit transient overvoltage, which, for this voltage range, is 3.0, as discussed later in this appendix. This is the maximum phase-to-ground transient overvoltage, which corresponds to the withstand voltage for the relevant exposure. 3
3 The withstand voltage is the voltage at which sparkover is not likely to occur across a specified distance. It is the voltage taken at the 3σ point below the sparkover voltage, assuming that the sparkover curve follows a normal distribution.
4. Divide the maximum phase-to-ground transient overvoltage by 0.85 to determine the corresponding critical sparkover voltage. (The critical sparkover voltage is 3 standard deviations (or 15 percent) greater than the withstand voltage.)
5. Determine the electrical component of the minimum approach distance from Table 1 through interpolation.
| Step | Maximum system phase-to-phase voltage (kV) | |||
|---|---|---|---|---|
| 15 | 36 | 46 | 72.5 | |
| 1. Divide by √3 | 8.7 | 20.8 | 26.6 | 41.9 |
| 2. Multiply by √2 | 12.2 | 29.4 | 37.6 | 59.2 |
| 3. Multiply by 3.0 | 36.7 | 88.2 | 112.7 | 177.6 |
| 4. Divide by 0.85 | 43.2 | 103.7 | 132.6 | 208.9 |
| 5. Interpolate from Table 1 | 3 + (7.2/10) 1 | 14 + (8.7/9)*2 | 20 + (12.6/23)*5 | 35 + (16.9/26)*5 |
| Electrical component of MAD (cm) | 3.72 | 15.93 | 22.74 | 38.25 |
C. Voltages of 72.6 to 800 kilovolts. For voltages of 72.6 kilovolts to 800 kilovolts, this subpart bases the electrical component of minimum approach distances, before the application of any altitude correction factor, on the following formula:
Equation 1—For voltages of 72.6 kV to 800 kV
D
C
a
V
L-G
T
Where:
D
C
a = A factor relating to the saturation of air at system voltages of 345 kilovolts or higher; 4
4 Test data demonstrates that the saturation factor is greater than 0 at peak voltages of about 630 kilovolts. Systems operating at 345 kilovolts (or maximum system voltages of 362 kilovolts) can have peak maximum transient overvoltages exceeding 630 kilovolts. Table V-2 sets equations for calculating a based on peak voltage.
V L-G = Maximum system line-to-ground rms voltage in kilovolts—it should be the “actual” maximum, or the normal highest voltage for the range (for example, 10 percent above the nominal voltage); and
T
In Equation 1, C is 0.01: (1) For phase-to-ground exposures that the employer can demonstrate consist only of air across the approach distance (gap) and (2) for phase-to-phase exposures if the employer can demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap. Otherwise, C is 0.011.
In Equation 1, the term a varies depending on whether the employee's exposure is phase-to-ground or phase-to-phase and on whether objects are in the gap. The employer must use the equations in Table 3 to calculate a. Sparkover test data with insulation spanning the gap form the basis for the equations for phase-to-ground exposures, and sparkover test data with only air in the gap form the basis for the equations for phase-to-phase exposures. The phase-to-ground equations result in slightly higher values of a, and, consequently, produce larger minimum approach distances, than the phase-to-phase equations for the same value of V Peak.
In Equation 1, T is the maximum transient overvoltage factor in per unit. As noted earlier, § 1926.960(c)(1)(ii) requires the employer to determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis or assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table V-8. For phase-to-ground exposures, the employer uses this value, called T L-G, as T in Equation 1. IEEE Std 516-2009 provides the following formula to calculate the phase-to-phase maximum transient overvoltage, T L-L, from T L-G :
T
L-L
T
L-G
For phase-to-phase exposures, the employer uses this value as T in Equation 1.
D. Provisions for inadvertent movement. The minimum approach distance must include an “adder” to compensate for the inadvertent movement of the worker relative to an energized part or the movement of the part relative to the worker. This “adder” must account for this possible inadvertent movement and provide the worker with a comfortable and safe zone in which to work. Employers must add the distance for inadvertent movement (called the “ergonomic component of the minimum approach distance”) to the electrical component to determine the total safe minimum approach distances used in live-line work.
The Occupational Safety and Health Administration based the ergonomic component of the minimum approach distance on response time-distance analysis. This technique uses an estimate of the total response time to a hazardous incident and converts that time to the distance traveled. For example, the driver of a car takes a given amount of time to respond to a “stimulus” and stop the vehicle. The elapsed time involved results in the car's traveling some distance before coming to a complete stop. This distance depends on the speed of the car at the time the stimulus appears and the reaction time of the driver.
In the case of live-line work, the employee must first perceive that he or she is approaching the danger zone. Then, the worker responds to the danger and must decelerate and stop all motion toward the energized part. During the time it takes to stop, the employee will travel some distance. This is the distance the employer must add to the electrical component of the minimum approach distance to obtain the total safe minimum approach distance.
At voltages from 751 volts to 72.5 kilovolts, 5 the electrical component of the minimum approach distance is smaller than the ergonomic component. At 72.5 kilovolts, the electrical component is only a little more than 0.3 meters (1 foot). An ergonomic component of the minimum approach distance must provide for all the worker's unanticipated movements. At these voltages, workers generally use rubber insulating gloves; however, these gloves protect only a worker's hands and arms. Therefore, the energized object must be at a safe approach distance to protect the worker's face. In this case, 0.61 meters (2 feet) is a sufficient and practical ergonomic component of the minimum approach distance.
5 For voltages of 50 to 300 volts, Table V-2 specifies a minimum approach distance of “avoid contact.” The minimum approach distance for this voltage range contains neither an electrical component nor an ergonomic component.
For voltages between 72.6 and 800 kilovolts, employees must use different work practices during energized line work. Generally, employees use live-line tools (hot sticks) to perform work on energized equipment. These tools, by design, keep the energized part at a constant distance from the employee and, thus, maintain the appropriate minimum approach distance automatically.
The location of the worker and the type of work methods the worker is using also influence the length of the ergonomic component of the minimum approach distance. In this higher voltage range, the employees use work methods that more tightly control their movements than when the workers perform work using rubber insulating gloves. The worker, therefore, is farther from the energized line or equipment and must be more precise in his or her movements just to perform the work. For these reasons, this subpart adopts an ergonomic component of the minimum approach distance of 0.31 m (1 foot) for voltages between 72.6 and 800 kilovolts.
| Voltage range (kV) | Distance | |
|---|---|---|
| m | ft | |
| 0.301 to 0.750 | 0.31 | 1.0 |
| 0.751 to 72.5 | 0.61 | 2.0 |
| 72.6 to 800 | 0.31 | 1.0 |
| Note : The employer must add this distance to the electrical component of the minimum approach distance to obtain the full minimum approach distance. |
The ergonomic component of the minimum approach distance accounts for errors in maintaining the minimum approach distance (which might occur, for example, if an employee misjudges the length of a conductive object he or she is holding), and for errors in judging the minimum approach distance. The ergonomic component also accounts for inadvertent movements by the employee, such as slipping. In contrast, the working position selected to properly maintain the minimum approach distance must account for all of an employee's reasonably likely movements and still permit the employee to adhere to the applicable minimum approach distance. (See Figure 1.) Reasonably likely movements include an employee's adjustments to tools, equipment, and working positions and all movements needed to perform the work. For example, the employee should be able to perform all of the following actions without straying into the minimum approach distance:
• Adjust his or her hardhat,
• maneuver a tool onto an energized part with a reasonable amount of overreaching or underreaching,
• reach for and handle tools, material, and equipment passed to him or her, and
• adjust tools, and replace components on them, when necessary during the work procedure.
The training of qualified employees required under § 1926.950, and the job planning and briefing required under § 1926.952, must address selection of a proper working position.
E. Miscellaneous correction factors. Changes in the air medium that forms the insulation influences the strength of an air gap. A brief discussion of each factor follows.
1. Dielectric strength of air. The dielectric strength of air in a uniform electric field at standard atmospheric conditions is approximately 3 kilovolts per millimeter. 6 The pressure, temperature, and humidity of the air, the shape, dimensions, and separation of the electrodes, and the characteristics of the applied voltage (wave shape) affect the disruptive gradient.
6 For the purposes of estimating arc length, Subpart V generally assumes a more conservative dielectric strength of 10 kilovolts per 25.4 millimeters, consistent with assumptions made in consensus standards such as the National Electrical Safety Code (IEEE C2-2012). The more conservative value accounts for variables such as electrode shape, wave shape, and a certain amount of overvoltage.
2. Atmospheric effect. The empirically determined electrical strength of a given gap is normally applicable at standard atmospheric conditions (20 °C, 101.3 kilopascals, 11 grams/cubic centimeter humidity). An increase in the density (humidity) of the air inhibits sparkover for a given air gap. The combination of temperature and air pressure that results in the lowest gap sparkover voltage is high temperature and low pressure. This combination of conditions is not likely to occur. Low air pressure, generally associated with high humidity, causes increased electrical strength. An average air pressure generally correlates with low humidity. Hot and dry working conditions normally result in reduced electrical strength. The equations for minimum approach distances in Table V-2 assume standard atmospheric conditions.
3. Altitude. The reduced air pressure at high altitudes causes a reduction in the electrical strength of an air gap. An employer must increase the minimum approach distance by about 3 percent per 300 meters (1,000 feet) of increased altitude for altitudes above 900 meters (3,000 feet). Table V-4 specifies the altitude correction factor that the employer must use in calculating minimum approach distances.
IV. Determining Minimum Approach Distances
A. Factors Affecting Voltage Stress at the Worksite
1. System voltage (nominal). The nominal system voltage range determines the voltage for purposes of calculating minimum approach distances. The employer selects the range in which the nominal system voltage falls, as given in the relevant table, and uses the highest value within that range in per-unit calculations.
2. Transient overvoltages. Operation of switches or circuit breakers, a fault on a line or circuit or on an adjacent circuit, and similar activities may generate transient overvoltages on an electrical system. Each overvoltage has an associated transient voltage wave shape. The wave shape arriving at the site and its magnitude vary considerably.
In developing requirements for minimum approach distances, the Occupational Safety and Health Administration considered the most common wave shapes and the magnitude of transient overvoltages found on electric power generation, transmission, and distribution systems. The equations in Table V-2 for minimum approach distances use per-unit maximum transient overvoltages, which are relative to the nominal maximum voltage of the system. For example, a maximum transient overvoltage value of 3.0 per unit indicates that the highest transient overvoltage is 3.0 times the nominal maximum system voltage.
3. Typical magnitude of overvoltages. Table 5 lists the magnitude of typical transient overvoltages.
| Cause | Magnitude (per unit) |
|---|---|
| Energized 200-mile line without closing resistors | 3.5 |
| Energized 200-mile line with one-step closing resistor | 2.1 |
| Energized 200-mile line with multistep resistor | 2.5 |
| Reclosing with trapped charge one-step resistor | 2.2 |
| Opening surge with single restrike | 3.0 |
| Fault initiation unfaulted phase | 2.1 |
| Fault initiation adjacent circuit | 2.5 |
| Fault clearing | 1.7 to 1.9 |
4. Standard deviation—air-gap withstand. For each air gap length under the same atmospheric conditions, there is a statistical variation in the breakdown voltage. The probability of breakdown against voltage has a normal (Gaussian) distribution. The standard deviation of this distribution varies with the wave shape, gap geometry, and atmospheric conditions. The withstand voltage of the air gap is three standard deviations (3σ) below the critical sparkover voltage. (The critical sparkover voltage is the crest value of the impulse wave that, under specified conditions, causes sparkover 50 percent of the time. An impulse wave of three standard deviations below this value, that is, the withstand voltage, has a probability of sparkover of approximately 1 in 1,000.)
5. Broken Insulators. Tests show reductions in the insulation strength of insulator strings with broken skirts. Broken units may lose up to 70 percent of their withstand capacity. Because an employer cannot determine the insulating capability of a broken unit without testing it, the employer must consider damaged units in an insulator to have no insulating value. Additionally, the presence of a live-line tool alongside an insulator string with broken units may further reduce the overall insulating strength. The number of good units that must be present in a string for it to be “insulated” as defined by § 1926.968 depends on the maximum overvoltage possible at the worksite.
B. Minimum Approach Distances Based on Known, Maximum-Anticipated Per-Unit Transient Overvoltages
1. Determining the minimum approach distance for AC systems. Under § 1926.960(c)(1)(ii), the employer must determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis or must assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table V-8. When the employer conducts an engineering analysis of the system and determines that the maximum transient overvoltage is lower than specified by Table V-8, the employer must ensure that any conditions assumed in the analysis, for example, that employees block reclosing on a circuit or install portable protective gaps, are present during energized work. To ensure that these conditions are present, the employer may need to institute new live-work procedures reflecting the conditions and limitations set by the engineering analysis.
2. Calculation of reduced approach distance values. An employer may take the following steps to reduce minimum approach distances when the maximum transient overvoltage on the system (that is, the maximum transient overvoltage without additional steps to control overvoltages) produces unacceptably large minimum approach distances:
Step 1. Determine the maximum voltage (with respect to a given nominal voltage range) for the energized part.
Step 2. Determine the technique to use to control the maximum transient overvoltage. (See paragraphs IV.C and IV.D of this appendix.) Determine the maximum transient overvoltage that can exist at the worksite with that form of control in place and with a confidence level of 3σ. This voltage is the withstand voltage for the purpose of calculating the appropriate minimum approach distance.
Step 3. Direct employees to implement procedures to ensure that the control technique is in effect during the course of the work.
Step 4. Using the new value of transient overvoltage in per unit, calculate the required minimum approach distance from Table V-2.
C. Methods of Controlling Possible Transient Overvoltage Stress Found on a System
1. Introduction. There are several means of controlling overvoltages that occur on transmission systems. For example, the employer can modify the operation of circuit breakers or other switching devices to reduce switching transient overvoltages. Alternatively, the employer can hold the overvoltage to an acceptable level by installing surge arresters or portable protective gaps on the system. In addition, the employer can change the transmission system to minimize the effect of switching operations. Section 4.8 of IEEE Std 516-2009 describes various ways of controlling, and thereby reducing, maximum transient overvoltages.
2. Operation of circuit breakers. 7 The maximum transient overvoltage that can reach the worksite is often the result of switching on the line on which employees are working. Disabling automatic reclosing during energized line work, so that the line will not be reenergized after being opened for any reason, limits the maximum switching surge overvoltage to the larger of the opening surge or the greatest possible fault-generated surge, provided that the devices (for example, insertion resistors) are operable and will function to limit the transient overvoltage and that circuit breaker restrikes do not occur. The employer must ensure the proper functioning of insertion resistors and other overvoltage-limiting devices when the employer's engineering analysis assumes their proper operation to limit the overvoltage level. If the employer cannot disable the reclosing feature (because of system operating conditions), other methods of controlling the switching surge level may be necessary.
7 The detailed design of a circuit interrupter, such as the design of the contacts, resistor insertion, and breaker timing control, are beyond the scope of this appendix. The design of the system generally accounts for these features. This appendix only discusses features that can limit the maximum switching transient overvoltage on a system.
Transient surges on an adjacent line, particularly for double circuit construction, may cause a significant overvoltage on the line on which employees are working. The employer's engineering analysis must account for coupling to adjacent lines.
3. Surge arresters. The use of modern surge arresters allows a reduction in the basic impulse-insulation levels of much transmission system equipment. The primary function of early arresters was to protect the system insulation from the effects of lightning. Modern arresters not only dissipate lightning-caused transients, but may also control many other system transients caused by switching or faults.
The employer may use properly designed arresters to control transient overvoltages along a transmission line and thereby reduce the requisite length of the insulator string and possibly the maximum transient overvoltage on the line. 8
8 Surge arrester application is beyond the scope of this appendix. However, if the employer installs the arrester near the work site, the application would be similar to the protective gaps discussed in paragraph IV.D of this appendix.
4. Switching Restrictions. Another form of overvoltage control involves establishing switching restrictions, whereby the employer prohibits the operation of circuit breakers until certain system conditions are present. The employer restricts switching by using a tagging system, similar to that used for a permit, except that the common term used for this activity is a “hold-off” or “restriction.” These terms indicate that the restriction does not prevent operation, but only modifies the operation during the live-work activity.
D. Minimum Approach Distance Based on Control of Maximum Transient Overvoltage at the Worksite
When the employer institutes control of maximum transient overvoltage at the worksite by installing portable protective gaps, the employer may calculate the minimum approach distance as follows:
Step 1. Select the appropriate withstand voltage for the protective gap based on system requirements and an acceptable probability of gap sparkover. 9
9 The employer should check the withstand voltage to ensure that it results in a probability of gap flashover that is acceptable from a system outage perspective. (In other words, a gap sparkover will produce a system outage. The employer should determine whether such an outage will impact overall system performance to an acceptable degree.) In general, the withstand voltage should be at least 1.25 times the maximum crest operating voltage.
Step 2. Determine a gap distance that provides a withstand voltage 10 greater than or equal to the one selected in the first step. 11
10 The manufacturer of the gap provides, based on test data, the critical sparkover voltage for each gap spacing (for example, a critical sparkover voltage of 665 kilovolts for a gap spacing of 1.2 meters). The withstand voltage for the gap is equal to 85 percent of its critical sparkover voltage.
11 Switch steps 1 and 2 if the length of the protective gap is known.
Step 3. Use 110 percent of the gap's critical sparkover voltage to determine the phase-to-ground peak voltage at gap sparkover ( V PPG Peak ).
Step 4. Determine the maximum transient overvoltage, phase-to-ground, at the worksite from the following formula:
Step 5. Use this value of T 12 in the equation in Table V-2 to obtain the minimum approach distance. If the worksite is no more than 900 meters (3,000 feet) above sea level, the employer may use this value of T to determine the minimum approach distance from Table 7 through Table 14.
12 IEEE Std 516-2009 states that most employers add 0.2 to the calculated value of T as an additional safety factor.
Sample protective gap calculations.
Problem: Employees are to perform work on a 500-kilovolt transmission line at sea level that is subject to transient overvoltages of 2.4 p.u. The maximum operating voltage of the line is 550 kilovolts. Determine the length of the protective gap that will provide the minimum practical safe approach distance. Also, determine what that minimum approach distance is.
Step 1. Calculate the smallest practical maximum transient overvoltage (1.25 times the crest phase-to-ground voltage): 13
13 To eliminate sparkovers due to minor system disturbances, the employer should use a withstand voltage no lower than 1.25 p.u. Note that this is a practical, or operational, consideration only. It may be feasible for the employer to use lower values of withstand voltage.
Step 2. Using test data for a particular protective gap, select a gap that has a critical sparkover voltage greater than or equal to:
kV
kV
For example, if a protective gap with a 1.22-m (4.0-foot) spacing tested to a critical sparkover voltage of 665 kilovolts (crest), select this gap spacing.
Step 3. The phase-to-ground peak voltage at gap sparkover ( V PPG Peak ) is 110 percent of the value from the previous step:
kV
kV
This value corresponds to the withstand voltage of the electrical component of the minimum approach distance.
Step 4. Use this voltage to determine the worksite value of T:
Step 5. Use this value of T in the equation in Table V-2 to obtain the minimum approach distance, or look up the minimum approach distance in Table 7 through Table 14:
MAD
E. Location of Protective Gaps
1. Adjacent structures. The employer may install the protective gap on a structure adjacent to the worksite, as this practice does not significantly reduce the protection afforded by the gap.
2. Terminal stations. Gaps installed at terminal stations of lines or circuits provide a level of protection; however, that level of protection may not extend throughout the length of the line to the worksite. The use of substation terminal gaps raises the possibility that separate surges could enter the line at opposite ends, each with low enough magnitude to pass the terminal gaps without sparkover. When voltage surges occur simultaneously at each end of a line and travel toward each other, the total voltage on the line at the point where they meet is the arithmetic sum of the two surges. A gap installed within 0.8 km (0.5 mile) of the worksite will protect against such intersecting waves. Engineering studies of a particular line or system may indicate that employers can adequately protect employees by installing gaps at even more distant locations. In any event, unless using the default values for T from Table V-8, the employer must determine T at the worksite.
3. Worksite. If the employer installs protective gaps at the worksite, the gap setting establishes the worksite impulse insulation strength. Lightning strikes as far as 6 miles from the worksite can cause a voltage surge greater than the gap withstand voltage, and a gap sparkover can occur. In addition, the gap can sparkover from overvoltages on the line that exceed the withstand voltage of the gap. Consequently, the employer must protect employees from hazards resulting from any sparkover that could occur.
F. Disabling automatic reclosing. There are two reasons to disable the automatic-reclosing feature of circuit-interrupting devices while employees are performing live-line work:
• To prevent reenergization of a circuit faulted during the work, which could create a hazard or result in more serious injuries or damage than the injuries or damage produced by the original fault;
• To prevent any transient overvoltage caused by the switching surge that would result if the circuit were reenergized.
However, due to system stability considerations, it may not always be feasible to disable the automatic-reclosing feature.
V. Minimum Approach-Distance Tables
A. Legacy tables. Employers may use the minimum approach distances in Table 6 until March 31, 2015.
| Voltage range phase to phase (kV) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 2.1 to 15.0 | 0.64 | 2.1 | 0.61 | 2.0 |
| 15.1 to 35.0 | 0.71 | 2.3 | 0.71 | 2.3 |
| 35.1 to 46.0 | 0.76 | 2.5 | 0.76 | 2.5 |
| 46.1 to 72.5 | 0.91 | 3.0 | 0.91 | 3.0 |
| 72.6 to 121 | 1.02 | 3.3 | 1.37 | 4.5 |
| 138 to 145 | 1.07 | 3.5 | 1.52 | 5.0 |
| 161 to 169 | 1.12 | 3.7 | 1.68 | 5.5 |
| 230 to 242 | 1.52 | 5.0 | 2.54 | 8.3 |
| 345 to 362 * | 2.13 | 7.0 | 4.06 | 13.3 |
| 500 to 552 * | 3.35 | 11.0 | 6.10 | 20.0 |
| 700 to 765 * | 4.57 | 15.0 | 9.45 | 31.0 |
| * The minimum approach distance may be the shortest distance between the energized part and the grounded surface. |
B. Alternative minimum approach distances. Employers may use the minimum approach distances in Table 7 through Table 14 provided that the employer follows the notes to those tables.
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 0.67 | 2.2 | 0.84 | 2.8 |
| 1.6 | 0.69 | 2.3 | 0.87 | 2.9 |
| 1.7 | 0.71 | 2.3 | 0.90 | 3.0 |
| 1.8 | 0.74 | 2.4 | 0.93 | 3.1 |
| 1.9 | 0.76 | 2.5 | 0.96 | 3.1 |
| 2.0 | 0.78 | 2.6 | 0.99 | 3.2 |
| 2.1 | 0.81 | 2.7 | 1.01 | 3.3 |
| 2.2 | 0.83 | 2.7 | 1.04 | 3.4 |
| 2.3 | 0.85 | 2.8 | 1.07 | 3.5 |
| 2.4 | 0.88 | 2.9 | 1.10 | 3.6 |
| 2.5 | 0.90 | 3.0 | 1.13 | 3.7 |
| 2.6 | 0.92 | 3.0 | 1.16 | 3.8 |
| 2.7 | 0.95 | 3.1 | 1.19 | 3.9 |
| 2.8 | 0.97 | 3.2 | 1.22 | 4.0 |
| 2.9 | 0.99 | 3.2 | 1.24 | 4.1 |
| 3.0 | 1.02 | 3.3 | 1.27 | 4.2 |
| 3.1 | 1.04 | 3.4 | 1.30 | 4.3 |
| 3.2 | 1.06 | 3.5 | 1.33 | 4.4 |
| 3.3 | 1.09 | 3.6 | 1.36 | 4.5 |
| 3.4 | 1.11 | 3.6 | 1.39 | 4.6 |
| 3.5 | 1.13 | 3.7 | 1.42 | 4.7 |
| T (p.u.) | Phase-to-ground rxposure | Phase-to-phase rxposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 0.74 | 2.4 | 0.95 | 3.1 |
| 1.6 | 0.76 | 2.5 | 0.98 | 3.2 |
| 1.7 | 0.79 | 2.6 | 1.02 | 3.3 |
| 1.8 | 0.82 | 2.7 | 1.05 | 3.4 |
| 1.9 | 0.85 | 2.8 | 1.08 | 3.5 |
| 2.0 | 0.88 | 2.9 | 1.12 | 3.7 |
| 2.1 | 0.90 | 3.0 | 1.15 | 3.8 |
| 2.2 | 0.93 | 3.1 | 1.19 | 3.9 |
| 2.3 | 0.96 | 3.1 | 1.22 | 4.0 |
| 2.4 | 0.99 | 3.2 | 1.26 | 4.1 |
| 2.5 | 1.02 | 3.3 | 1.29 | 4.2 |
| 2.6 | 1.04 | 3.4 | 1.33 | 4.4 |
| 2.7 | 1.07 | 3.5 | 1.36 | 4.5 |
| 2.8 | 1.10 | 3.6 | 1.39 | 4.6 |
| 2.9 | 1.13 | 3.7 | 1.43 | 4.7 |
| 3.0 | 1.16 | 3.8 | 1.46 | 4.8 |
| 3.1 | 1.19 | 3.9 | 1.50 | 4.9 |
| 3.2 | 1.21 | 4.0 | 1.53 | 5.0 |
| 3.3 | 1.24 | 4.1 | 1.57 | 5.2 |
| 3.4 | 1.27 | 4.2 | 1.60 | 5.2 |
| 3.5 | 1.30 | 4.3 | 1.64 | 5.4 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 0.81 | 2.7 | 1.05 | 3.4 |
| 1.6 | 0.84 | 2.8 | 1.09 | 3.6 |
| 1.7 | 0.87 | 2.9 | 1.13 | 3.7 |
| 1.8 | 0.90 | 3.0 | 1.17 | 3.8 |
| 1.9 | 0.94 | 3.1 | 1.21 | 4.0 |
| 2.0 | 0.97 | 3.2 | 1.25 | 4.1 |
| 2.1 | 1.00 | 3.3 | 1.29 | 4.2 |
| 2.2 | 1.03 | 3.4 | 1.33 | 4.4 |
| 2.3 | 1.07 | 3.5 | 1.37 | 4.5 |
| 2.4 | 1.10 | 3.6 | 1.41 | 4.6 |
| 2.5 | 1.13 | 3.7 | 1.45 | 4.8 |
| 2.6 | 1.17 | 3.8 | 1.49 | 4.9 |
| 2.7 | 1.20 | 3.9 | 1.53 | 5.0 |
| 2.8 | 1.23 | 4.0 | 1.57 | 5.2 |
| 2.9 | 1.26 | 4.1 | 1.61 | 5.3 |
| 3.0 | 1.30 | 4.3 | 1.65 | 5.4 |
| 3.1 | 1.33 | 4.4 | 1.70 | 5.6 |
| 3.2 | 1.36 | 4.5 | 1.76 | 5.8 |
| 3.3 | 1.39 | 4.6 | 1.82 | 6.0 |
| 3.4 | 1.43 | 4.7 | 1.88 | 6.2 |
| 3.5 | 1.46 | 4.8 | 1.94 | 6.4 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.02 | 3.3 | 1.37 | 4.5 |
| 1.6 | 1.06 | 3.5 | 1.43 | 4.7 |
| 1.7 | 1.11 | 3.6 | 1.48 | 4.9 |
| 1.8 | 1.16 | 3.8 | 1.54 | 5.1 |
| 1.9 | 1.21 | 4.0 | 1.60 | 5.2 |
| 2.0 | 1.25 | 4.1 | 1.66 | 5.4 |
| 2.1 | 1.30 | 4.3 | 1.73 | 5.7 |
| 2.2 | 1.35 | 4.4 | 1.81 | 5.9 |
| 2.3 | 1.39 | 4.6 | 1.90 | 6.2 |
| 2.4 | 1.44 | 4.7 | 1.99 | 6.5 |
| 2.5 | 1.49 | 4.9 | 2.08 | 6.8 |
| 2.6 | 1.53 | 5.0 | 2.17 | 7.1 |
| 2.7 | 1.58 | 5.2 | 2.26 | 7.4 |
| 2.8 | 1.63 | 5.3 | 2.36 | 7.7 |
| 2.9 | 1.67 | 5.5 | 2.45 | 8.0 |
| 3.0 | 1.72 | 5.6 | 2.55 | 8.4 |
| 3.1 | 1.77 | 5.8 | 2.65 | 8.7 |
| 3.2 | 1.81 | 5.9 | 2.76 | 9.1 |
| 3.3 | 1.88 | 6.2 | 2.86 | 9.4 |
| 3.4 | 1.95 | 6.4 | 2.97 | 9.7 |
| 3.5 | 2.01 | 6.6 | 3.08 | 10.1 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.37 | 4.5 | 1.99 | 6.5 |
| 1.6 | 1.44 | 4.7 | 2.13 | 7.0 |
| 1.7 | 1.51 | 5.0 | 2.27 | 7.4 |
| 1.8 | 1.58 | 5.2 | 2.41 | 7.9 |
| 1.9 | 1.65 | 5.4 | 2.56 | 8.4 |
| 2.0 | 1.72 | 5.6 | 2.71 | 8.9 |
| 2.1 | 1.79 | 5.9 | 2.87 | 9.4 |
| 2.2 | 1.87 | 6.1 | 3.03 | 9.9 |
| 2.3 | 1.97 | 6.5 | 3.20 | 10.5 |
| 2.4 | 2.08 | 6.8 | 3.37 | 11.1 |
| 2.5 | 2.19 | 7.2 | 3.55 | 11.6 |
| 2.6 | 2.29 | 7.5 | 3.73 | 12.2 |
| 2.7 | 2.41 | 7.9 | 3.91 | 12.8 |
| 2.8 | 2.52 | 8.3 | 4.10 | 13.5 |
| 2.9 | 2.64 | 8.7 | 4.29 | 14.1 |
| 3.0 | 2.76 | 9.1 | 4.49 | 14.7 |
| 3.1 | 2.88 | 9.4 | 4.69 | 15.4 |
| 3.2 | 3.01 | 9.9 | 4.90 | 16.1 |
| 3.3 | 3.14 | 10.3 | 5.11 | 16.8 |
| 3.4 | 3.27 | 10.7 | 5.32 | 17.5 |
| 3.5 | 3.41 | 11.2 | 5.52 | 18.1 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.53 | 5.0 | 2.40 | 7.9 |
| 1.6 | 1.62 | 5.3 | 2.58 | 8.5 |
| 1.7 | 1.70 | 5.6 | 2.75 | 9.0 |
| 1.8 | 1.78 | 5.8 | 2.94 | 9.6 |
| 1.9 | 1.88 | 6.2 | 3.13 | 10.3 |
| 2.0 | 1.99 | 6.5 | 3.33 | 10.9 |
| 2.1 | 2.12 | 7.0 | 3.53 | 11.6 |
| 2.2 | 2.24 | 7.3 | 3.74 | 12.3 |
| 2.3 | 2.37 | 7.8 | 3.95 | 13.0 |
| 2.4 | 2.50 | 8.2 | 4.17 | 13.7 |
| 2.5 | 2.64 | 8.7 | 4.40 | 14.4 |
| 2.6 | 2.78 | 9.1 | 4.63 | 15.2 |
| 2.7 | 2.93 | 9.6 | 4.87 | 16.0 |
| 2.8 | 3.07 | 10.1 | 5.11 | 16.8 |
| 2.9 | 3.23 | 10.6 | 5.36 | 17.6 |
| 3.0 | 3.38 | 11.1 | 5.59 | 18.3 |
| 3.1 | 3.55 | 11.6 | 5.82 | 19.1 |
| 3.2 | 3.72 | 12.2 | 6.07 | 19.9 |
| 3.3 | 3.89 | 12.8 | 6.31 | 20.7 |
| 3.4 | 4.07 | 13.4 | 6.56 | 21.5 |
| 3.5 | 4.25 | 13.9 | 6.81 | 22.3 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 1.95 | 6.4 | 3.46 | 11.4 |
| 1.6 | 2.11 | 6.9 | 3.73 | 12.2 |
| 1.7 | 2.28 | 7.5 | 4.02 | 13.2 |
| 1.8 | 2.45 | 8.0 | 4.31 | 14.1 |
| 1.9 | 2.62 | 8.6 | 4.61 | 15.1 |
| 2.0 | 2.81 | 9.2 | 4.92 | 16.1 |
| 2.1 | 3.00 | 9.8 | 5.25 | 17.2 |
| 2.2 | 3.20 | 10.5 | 5.55 | 18.2 |
| 2.3 | 3.40 | 11.2 | 5.86 | 19.2 |
| 2.4 | 3.62 | 11.9 | 6.18 | 20.3 |
| 2.5 | 3.84 | 12.6 | 6.50 | 21.3 |
| 2.6 | 4.07 | 13.4 | 6.83 | 22.4 |
| 2.7 | 4.31 | 14.1 | 7.18 | 23.6 |
| 2.8 | 4.56 | 15.0 | 7.52 | 24.7 |
| 2.9 | 4.81 | 15.8 | 7.88 | 25.9 |
| 3.0 | 5.07 | 16.6 | 8.24 | 27.0 |
| T (p.u.) | Phase-to-ground exposure | Phase-to-phase exposure | ||
|---|---|---|---|---|
| m | ft | m | ft | |
| 1.5 | 3.16 | 10.4 | 5.97 | 19.6 |
| 1.6 | 3.46 | 11.4 | 6.43 | 21.1 |
| 1.7 | 3.78 | 12.4 | 6.92 | 22.7 |
| 1.8 | 4.12 | 13.5 | 7.42 | 24.3 |
| 1.9 | 4.47 | 14.7 | 7.93 | 26.0 |
| 2.0 | 4.83 | 15.8 | 8.47 | 27.8 |
| 2.1 | 5.21 | 17.1 | 9.02 | 29.6 |
| 2.2 | 5.61 | 18.4 | 9.58 | 31.4 |
| 2.3 | 6.02 | 19.8 | 10.16 | 33.3 |
| 2.4 | 6.44 | 21.1 | 10.76 | 35.3 |
| 2.5 | 6.88 | 22.6 | 11.38 | 37.3 |
| Notes to Table 7 through Table 14: | ||||
| 1. The employer must determine the maximum anticipated per-unit transient overvoltage, phase-to-ground, through an engineering analysis, as required by § 1926.960(c)(1)(ii), or assume a maximum anticipated per-unit transient overvoltage, phase-to-ground, in accordance with Table V-8. | ||||
| 2. For phase-to-phase exposures, the employer must demonstrate that no insulated tool spans the gap and that no large conductive object is in the gap. | ||||
| 3. The worksite must be at an elevation of 900 meters (3,000 feet) or less above sea level. |
[79 FR 20696, Apr. 11, 2014, as amended at 79 FR 56962, Sept. 24, 2014]
I. Introduction
Current passing through an impedance impresses voltage across that impedance. Even conductors have some, albeit low, value of impedance. Therefore, if a “grounded” 1 object, such as a crane or deenergized and grounded power line, results in a ground fault on a power line, voltage is impressed on that grounded object. The voltage impressed on the grounded object depends largely on the voltage on the line, on the impedance of the faulted conductor, and on the impedance to “true,” or “absolute,” ground represented by the object. If the impedance of the object causing the fault is relatively large, the voltage impressed on the object is essentially the phase-to-ground system voltage. However, even faults to grounded power lines or to well grounded transmission towers or substation structures (which have relatively low values of impedance to ground) can result in hazardous voltages. 2 In all cases, the degree of the hazard depends on the magnitude of the current through the employee and the time of exposure. This appendix discusses methods of protecting workers against the possibility that grounded objects, such as cranes and other mechanical equipment, will contact energized power lines and that deenergized and grounded power lines will become accidentally energized.
1 This appendix generally uses the term “grounded” only with respect to grounding that the employer intentionally installs, for example, the grounding an employer installs on a deenergized conductor. However, in this case, the term “grounded” means connected to earth, regardless of whether or not that connection is intentional.
2 Thus, grounding systems for transmission towers and substation structures should be designed to minimize the step and touch potentials involved.
II. Voltage-Gradient Distribution
A. Voltage-gradient distribution curve. Absolute, or true, ground serves as a reference and always has a voltage of 0 volts above ground potential. Because there is an impedance between a grounding electrode and absolute ground, there will be a voltage difference between the grounding electrode and absolute ground under ground-fault conditions. Voltage dissipates from the grounding electrode (or from the grounding point) and creates a ground potential gradient. The voltage decreases rapidly with increasing distance from the grounding electrode. A voltage drop associated with this dissipation of voltage is a ground potential. Figure 1 is a typical voltage-gradient distribution curve (assuming a uniform soil texture).
B. Step and touch potentials. Figure 1 also shows that workers are at risk from step and touch potentials. Step potential is the voltage between the feet of a person standing near an energized grounded object (the electrode). In Figure 1, the step potential is equal to the difference in voltage between two points at different distances from the electrode (where the points represent the location of each foot in relation to the electrode). A person could be at risk of injury during a fault simply by standing near the object.
Touch potential is the voltage between the energized grounded object (again, the electrode) and the feet of a person in contact with the object. In Figure 1, the touch potential is equal to the difference in voltage between the electrode (which is at a distance of 0 meters) and a point some distance away from the electrode (where the point represents the location of the feet of the person in contact with the object). The touch potential could be nearly the full voltage across the grounded object if that object is grounded at a point remote from the place where the person is in contact with it. For example, a crane grounded to the system neutral and that contacts an energized line would expose any person in contact with the crane or its uninsulated load line to a touch potential nearly equal to the full fault voltage.
A. Definitions. The following definitions apply to section III of this appendix:
Bond. The electrical interconnection of conductive parts designed to maintain a common electric potential.
Bonding cable (bonding jumper). A cable connected to two conductive parts to bond the parts together.
Cluster bar. A terminal temporarily attached to a structure that provides a means for the attachment and bonding of grounding and bonding cables to the structure.
Ground. A conducting connection between an electric circuit or equipment and the earth, or to some conducting body that serves in place of the earth.
Grounding cable (grounding jumper). A cable connected between a deenergized part and ground. Note that grounding cables carry fault current and bonding cables generally do not. A cable that bonds two conductive parts but carries substantial fault current (for example, a jumper connected between one phase and a grounded phase) is a grounding cable.
Ground mat (grounding grid). A temporarily or permanently installed metallic mat or grating that establishes an equipotential surface and provides connection points for attaching grounds.
B. Analyzing the hazard. The employer can use an engineering analysis of the power system under fault conditions to determine whether hazardous step and touch voltages will develop. The analysis should determine the voltage on all conductive objects in the work area and the amount of time the voltage will be present. Based on the this analysis, the employer can select appropriate measures and protective equipment, including the measures and protective equipment outlined in Section III of this appendix, to protect each employee from hazardous differences in electric potential. For example, from the analysis, the employer will know the voltage remaining on conductive objects after employees install bonding and grounding equipment and will be able to select insulating equipment with an appropriate rating, as described in paragraph III.C.2 of this appendix.
C. Protecting workers on the ground. The employer may use several methods, including equipotential zones, insulating equipment, and restricted work areas, to protect employees on the ground from hazardous differences in electrical potential.
1. An equipotential zone will protect workers within it from hazardous step and touch potentials. (See Figure 3.) Equipotential zones will not, however, protect employees located either wholly or partially outside the protected area. The employer can establish an equipotential zone for workers on the ground, with respect to a grounded object, through the use of a metal mat connected to the grounded object. The employer can use a grounding grid to equalize the voltage within the grid or bond conductive objects in the immediate work area to minimize the potential between the objects and between each object and ground. (Bonding an object outside the work area can increase the touch potential to that object, however.) Section III.D of this appendix discusses equipotential zones for employees working on deenergized and grounded power lines.
2. Insulating equipment, such as rubber gloves, can protect employees handling grounded equipment and conductors from hazardous touch potentials. The insulating equipment must be rated for the highest voltage that can be impressed on the grounded objects under fault conditions (rather than for the full system voltage).
3. Restricting employees from areas where hazardous step or touch potentials could arise can protect employees not directly involved in performing the operation. The employer must ensure that employees on the ground in the vicinity of transmission structures are at a distance where step voltages would be insufficient to cause injury. Employees must not handle grounded conductors or equipment likely to become energized to hazardous voltages unless the employees are within an equipotential zone or protected by insulating equipment.
D. Protecting employees working on deenergized and grounded power lines. This Section III.D of Appendix C establishes guidelines to help employers comply with requirements in § 1926.962 for using protective grounding to protect employees working on deenergized power lines. Section 1926.962 applies to grounding of transmission and distribution lines and equipment for the purpose of protecting workers. Paragraph (c) of § 1926.962 requires temporary protective grounds to be placed at such locations and arranged in such a manner that the employer can demonstrate will prevent exposure of each employee to hazardous differences in electric potential. 3 Sections III.D.1 and III.D.2 of this appendix provide guidelines that employers can use in making the demonstration required by § 1926.962(c). Section III.D.1 of this appendix provides guidelines on how the employer can determine whether particular grounding practices expose employees to hazardous differences in electric potential. Section III.D.2 of this appendix describes grounding methods that the employer can use in lieu of an engineering analysis to make the demonstration required by § 1926.962(c). The Occupational Safety and Health Administration will consider employers that comply with the criteria in this appendix as meeting § 1926.962(c).
3 The protective grounding required by § 1926.962 limits to safe values the potential differences between accessible objects in each employee's work environment. Ideally, a protective grounding system would create a true equipotential zone in which every point is at the same electric potential. In practice, current passing through the grounding and bonding elements creates potential differences. If these potential differences are hazardous, the employer may not treat the zone as an equipotential zone.
Finally, Section III.D.3 of this appendix discusses other safety considerations that will help the employer comply with other requirements in § 1926.962. Following these guidelines will protect workers from hazards that can occur when a deenergized and grounded line becomes energized.
1. Determining safe body current limits. This Section III.D.1 of Appendix C provides guidelines on how an employer can determine whether any differences in electric potential to which workers could be exposed are hazardous as part of the demonstration required by § 1926.962(c).
Institute of Electrical and Electronic Engineers (IEEE) Standard 1048-2003, IEEE Guide for Protective Grounding of Power Lines, provides the following equation for determining the threshold of ventricular fibrillation when the duration of the electric shock is limited:
where I is the current through the worker's body, and t is the duration of the current in seconds. This equation represents the ventricular fibrillation threshold for 95.5 percent of the adult population with a mass of 50 kilograms (110 pounds) or more. The equation is valid for current durations between 0.0083 to 3.0 seconds.
To use this equation to set safe voltage limits in an equipotential zone around the worker, the employer will need to assume a value for the resistance of the worker's body. IEEE Std 1048-2003 states that “total body resistance is usually taken as 1000 Ω for determining... body current limits.” However, employers should be aware that the impedance of a worker's body can be substantially less than that value. For instance, IEEE Std 1048-2003 reports a minimum hand-to-hand resistance of 610 ohms and an internal body resistance of 500 ohms. The internal resistance of the body better represents the minimum resistance of a worker's body when the skin resistance drops near zero, which occurs, for example, when there are breaks in the worker's skin, for instance, from cuts or from blisters formed as a result of the current from an electric shock, or when the worker is wet at the points of contact.
Employers may use the IEEE Std 1048-2003 equation to determine safe body current limits only if the employer protects workers from hazards associated with involuntary muscle reactions from electric shock (for example, the hazard to a worker from falling as a result of an electric shock). Moreover, the equation applies only when the duration of the electric shock is limited. If the precautions the employer takes, including those required by applicable standards, do not adequately protect employees from hazards associated with involuntary reactions from electric shock, a hazard exists if the induced voltage is sufficient to pass a current of 1 milliampere through a 500-ohm resistor. (The 500-ohm resistor represents the resistance of an employee. The 1-milliampere current is the threshold of perception.) Finally, if the employer protects employees from injury due to involuntary reactions from electric shock, but the duration of the electric shock is unlimited (that is, when the fault current at the work location will be insufficient to trip the devices protecting the circuit), a hazard exists if the resultant current would be more than 6 milliamperes (the recognized let-go threshold for workers 4 ).
4 Electric current passing through the body has varying effects depending on the amount of the current. At the let-go threshold, the current overrides a person's control over his or her muscles. At that level, an employee grasping an object will not be able to let go of the object. The let-go threshold varies from person to person; however, the recognized value for workers is 6 milliamperes.
2. Acceptable methods of grounding for employers that do not perform an engineering determination. The grounding methods presented in this section of this appendix ensure that differences in electric potential are as low as possible and, therefore, meet § 1926.962(c) without an engineering determination of the potential differences. These methods follow two principles: (i) The grounding method must ensure that the circuit opens in the fastest available clearing time, and (ii) the grounding method must ensure that the potential differences between conductive objects in the employee's work area are as low as possible.
Paragraph (c) of § 1926.962 does not require grounding methods to meet the criteria embodied in these principles. Instead, the paragraph requires that protective grounds be “placed at such locations and arranged in such a manner that the employer can demonstrate will prevent exposure of each employee to hazardous differences in electric potential.” However, when the employer's grounding practices do not follow these two principles, the employer will need to perform an engineering analysis to make the demonstration required by § 1926.962(c).
i. Ensuring that the circuit opens in the fastest available clearing time. Generally, the higher the fault current, the shorter the clearing times for the same type of fault. Therefore, to ensure the fastest available clearing time, the grounding method must maximize the fault current with a low impedance connection to ground. The employer accomplishes this objective by grounding the circuit conductors to the best ground available at the worksite. Thus, the employer must ground to a grounded system neutral conductor, if one is present. A grounded system neutral has a direct connection to the system ground at the source, resulting in an extremely low impedance to ground. In a substation, the employer may instead ground to the substation grid, which also has an extremely low impedance to the system ground and, typically, is connected to a grounded system neutral when one is present. Remote system grounds, such as pole and tower grounds, have a higher impedance to the system ground than grounded system neutrals and substation grounding grids; however, the employer may use a remote ground when lower impedance grounds are not available. In the absence of a grounded system neutral, substation grid, and remote ground, the employer may use a temporary driven ground at the worksite.
In addition, if employees are working on a three-phase system, the grounding method must short circuit all three phases. Short circuiting all phases will ensure faster clearing and lower the current through the grounding cable connecting the deenergized line to ground, thereby lowering the voltage across that cable. The short circuit need not be at the worksite; however, the employer must treat any conductor that is not grounded at the worksite as energized because the ungrounded conductors will be energized at fault voltage during a fault.
ii. Ensuring that the potential differences between conductive objects in the employee's work area are as low as possible. To achieve as low a voltage as possible across any two conductive objects in the work area, the employer must bond all conductive objects in the work area. This section of this appendix discusses how to create a zone that minimizes differences in electric potential between conductive objects in the work area.
The employer must use bonding cables to bond conductive objects, except for metallic objects bonded through metal-to-metal contact. The employer must ensure that metal-to-metal contacts are tight and free of contamination, such as oxidation, that can increase the impedance across the connection. For example, a bolted connection between metal lattice tower members is acceptable if the connection is tight and free of corrosion and other contamination. Figure 4 shows how to create an equipotential zone for metal lattice towers.
Wood poles are conductive objects. The poles can absorb moisture and conduct electricity, particularly at distribution and transmission voltages. Consequently, the employer must either: (1) Provide a conductive platform, bonded to a grounding cable, on which the worker stands or (2) use cluster bars to bond wood poles to the grounding cable. The employer must ensure that employees install the cluster bar below, and close to, the worker's feet. The inner portion of the wood pole is more conductive than the outer shell, so it is important that the cluster bar be in conductive contact with a metal spike or nail that penetrates the wood to a depth greater than or equal to the depth the worker's climbing gaffs will penetrate the wood. For example, the employer could mount the cluster bar on a bare pole ground wire fastened to the pole with nails or staples that penetrate to the required depth. Alternatively, the employer may temporarily nail a conductive strap to the pole and connect the strap to the cluster bar. Figure 5 shows how to create an equipotential zone for wood poles.
For underground systems, employers commonly install grounds at the points of disconnection of the underground cables. These grounding points are typically remote from the manhole or underground vault where employees will be working on the cable. Workers in contact with a cable grounded at a remote location can experience hazardous potential differences if the cable becomes energized or if a fault occurs on a different, but nearby, energized cable. The fault current causes potential gradients in the earth, and a potential difference will exist between the earth where the worker is standing and the earth where the cable is grounded. Consequently, to create an equipotential zone for the worker, the employer must provide a means of connecting the deenergized cable to ground at the worksite by having the worker stand on a conductive mat bonded to the deenergized cable. If the cable is cut, the employer must install a bond across the opening in the cable or install one bond on each side of the opening to ensure that the separate cable ends are at the same potential. The employer must protect the worker from any hazardous differences in potential any time there is no bond between the mat and the cable (for example, before the worker installs the bonds).
3. Other safety-related considerations. To ensure that the grounding system is safe and effective, the employer should also consider the following factors: 5
5 This appendix only discusses factors that relate to ensuring an equipotential zone for employees. The employer must consider other factors in selecting a grounding system that is capable of conducting the maximum fault current that could flow at the point of grounding for the time necessary to clear the fault, as required by § 1926.962(d)(1)(i). IEEE Std 1048-2003 contains guidelines for selecting and installing grounding equipment that will meet § 1926.962(d)(1)(i).
i. Maintenance of grounding equipment. It is essential that the employer properly maintain grounding equipment. Corrosion in the connections between grounding cables and clamps and on the clamp surface can increase the resistance of the cable, thereby increasing potential differences. In addition, the surface to which a clamp attaches, such as a conductor or tower member, must be clean and free of corrosion and oxidation to ensure a low-resistance connection. Cables must be free of damage that could reduce their current-carrying capacity so that they can carry the full fault current without failure. Each clamp must have a tight connection to the cable to ensure a low resistance and to ensure that the clamp does not separate from the cable during a fault.
ii. Grounding cable length and movement. The electromagnetic forces on grounding cables during a fault increase with increasing cable length. These forces can cause the cable to move violently during a fault and can be high enough to damage the cable or clamps and cause the cable to fail. In addition, flying cables can injure workers. Consequently, cable lengths should be as short as possible, and grounding cables that might carry high fault current should be in positions where the cables will not injure workers during a fault.
I. Introduction
When employees are to perform work on a wood pole, it is important to determine the condition of the pole before employees climb it. The weight of the employee, the weight of equipment to be installed, and other working stresses (such as the removal or retensioning of conductors) can lead to the failure of a defective pole or a pole that is not designed to handle the additional stresses. 1 For these reasons, it is essential that, before an employee climbs a wood pole, the employer ascertain that the pole is capable of sustaining the stresses of the work. The determination that the pole is capable of sustaining these stresses includes an inspection of the condition of the pole.
1 A properly guyed pole in good condition should, at a minimum, be able to handle the weight of an employee climbing it.
If the employer finds the pole to be unsafe to climb or to work from, the employer must secure the pole so that it does not fail while an employee is on it. The employer can secure the pole by a line truck boom, by ropes or guys, or by lashing a new pole alongside it. If a new one is lashed alongside the defective pole, employees should work from the new one.
II. Inspecting Wood Poles
A qualified employee should inspect wood poles for the following conditions: 2
2 The presence of any of these conditions is an indication that the pole may not be safe to climb or to work from. The employee performing the inspection must be qualified to make a determination as to whether it is safe to perform the work without taking additional precautions.
A. General condition. Buckling at the ground line or an unusual angle with respect to the ground may indicate that the pole has rotted or is broken.
B. Cracks. Horizontal cracks perpendicular to the grain of the wood may weaken the pole. Vertical cracks, although not normally considered to be a sign of a defective pole, can pose a hazard to the climber, and the employee should keep his or her gaffs away from them while climbing.
C. Holes. Hollow spots and woodpecker holes can reduce the strength of a wood pole.
D. Shell rot and decay. Rotting and decay are cutout hazards and possible indications of the age and internal condition of the pole.
E. Knots. One large knot or several smaller ones at the same height on the pole may be evidence of a weak point on the pole.
F. Depth of setting. Evidence of the existence of a former ground line substantially above the existing ground level may be an indication that the pole is no longer buried to a sufficient depth.
G. Soil conditions. Soft, wet, or loose soil around the base of the pole may indicate that the pole will not support any change in stress.
H. Burn marks. Burning from transformer failures or conductor faults could damage the pole so that it cannot withstand changes in mechanical stress.
III. Testing Wood Poles
The following tests, which are from § 1910.268(n)(3) of this chapter, are acceptable methods of testing wood poles:
A. Hammer test. Rap the pole sharply with a hammer weighing about 1.4 kg (3 pounds), starting near the ground line and continuing upwards circumferentially around the pole to a height of approximately 1.8 meters (6 feet). The hammer will produce a clear sound and rebound sharply when striking sound wood. Decay pockets will be indicated by a dull sound or a less pronounced hammer rebound. Also, prod the pole as near the ground line as possible using a pole prod or a screwdriver with a blade at least 127 millimeters (5 inches) long. If substantial decay is present, the pole is unsafe.
B. Rocking test. Apply a horizontal force to the pole and attempt to rock it back and forth in a direction perpendicular to the line. Exercise caution to avoid causing power lines to swing together. Apply the force to the pole either by pushing it with a pike pole or pulling the pole with a rope. If the pole cracks during the test, it is unsafe.
I. Introduction
Paragraph (g) of § 1926.960 addresses protecting employees from flames and electric arcs. This paragraph requires employers to: (1) Assess the workplace for flame and electric-arc hazards (paragraph (g)(1)); (2) estimate the available heat energy from electric arcs to which employees would be exposed (paragraph (g)(2)); (3) ensure that employees wear clothing that will not melt, or ignite and continue to burn, when exposed to flames or the estimated heat energy (paragraph (g)(3)); and (4) ensure that employees wear flame-resistant clothing 1 and protective clothing and other protective equipment that has an arc rating greater than or equal to the available heat energy under certain conditions (paragraphs (g)(4) and (g)(5)). This appendix contains information to help employers estimate available heat energy as required by § 1926.960(g)(2), select protective clothing and other protective equipment with an arc rating suitable for the available heat energy as required by § 1926.960(g)(5), and ensure that employees do not wear flammable clothing that could lead to burn injury as addressed by §§ 1926.960(g)(3) and (g)(4).
1 Flame-resistant clothing includes clothing that is inherently flame resistant and clothing chemically treated with a flame retardant. (See ASTM F1506-10a, Standard Performance Specification for Flame Resistant Textile Materials for Wearing Apparel for Use by Electrical Workers Exposed to Momentary Electric Arc and Related Thermal Hazards, and ASTM F1891-12 Standard Specification for Arc and Flame Resistant Rainwear. )
II. Assessing the Workplace for Flame and Electric-Arc Hazards
Paragraph (g)(1) of § 1926.960 requires the employer to assess the workplace to identify employees exposed to hazards from flames or from electric arcs. This provision ensures that the employer evaluates employee exposure to flames and electric arcs so that employees who face such exposures receive the required protection. The employer must conduct an assessment for each employee who performs work on or near exposed, energized parts of electric circuits.
A. Assessment Guidelines
Sources electric arcs. Consider possible sources of electric arcs, including:
• Energized circuit parts not guarded or insulated,
• Switching devices that produce electric arcs in normal operation,
• Sliding parts that could fault during operation (for example, rack-mounted circuit breakers), and
• Energized electric equipment that could fail (for example, electric equipment with damaged insulation or with evidence of arcing or overheating).
Exposure to flames. Identify employees exposed to hazards from flames. Factors to consider include:
• The proximity of employees to open flames, and
• For flammable material in the work area, whether there is a reasonable likelihood that an electric arc or an open flame can ignite the material.
Probability that an electric arc will occur. Identify employees exposed to electric-arc hazards. The Occupational Safety and Health Administration will consider an employee exposed to electric-arc hazards if there is a reasonable likelihood that an electric arc will occur in the employee's work area, in other words, if the probability of such an event is higher than it is for the normal operation of enclosed equipment. Factors to consider include:
• For energized circuit parts not guarded or insulated, whether conductive objects can come too close to or fall onto the energized parts,
• For exposed, energized circuit parts, whether the employee is closer to the part than the minimum approach distance established by the employer (as permitted by § 1926.960(c)(1)(iii)).
• Whether the operation of electric equipment with sliding parts that could fault during operation is part of the normal operation of the equipment or occurs during servicing or maintenance, and
• For energized electric equipment, whether there is evidence of impending failure, such as evidence of arcing or overheating.
B. Examples
| Task | Is employee exposed to flame or electric-arc hazard? | |
|---|---|---|
| Normal operation of enclosed equipment, such as closing or opening a switch | The employer properly installs and maintains enclosed equipment, and there is no evidence of impending failure | No. |
| There is evidence of arcing or overheating | Yes. | |
| Parts of the equipment are loose or sticking, or the equipment otherwise exhibits signs of lack of maintenance | Yes. | |
| Servicing electric equipment, such as racking in a circuit breaker or replacing a switch | Yes. | |
| Inspection of electric equipment with exposed energized parts | The employee is not holding conductive objects and remains outside the minimum approach distance established by the employer | No. |
| The employee is holding a conductive object, such as a flashlight, that could fall or otherwise contact energized parts (irrespective of whether the employee maintains the minimum approach distance) | Yes. | |
| The employee is closer than the minimum approach distance established by the employer (for example, when wearing rubber insulating gloves or rubber insulating gloves and sleeves) | Yes. | |
| Using open flames, for example, in wiping cable splice sleeves | Yes. |
III. Protection Against Burn Injury
A. Estimating Available Heat Energy
Calculation methods. Paragraph (g)(2) of § 1926.960 provides that, for each employee exposed to an electric-arc hazard, the employer must make a reasonable estimate of the heat energy to which the employee would be exposed if an arc occurs. Table 2 lists various methods of calculating values of available heat energy from an electric circuit. The Occupational Safety and Health Administration does not endorse any of these specific methods. Each method requires the input of various parameters, such as fault current, the expected length of the electric arc, the distance from the arc to the employee, and the clearing time for the fault (that is, the time the circuit protective devices take to open the circuit and clear the fault). The employer can precisely determine some of these parameters, such as the fault current and the clearing time, for a given system. The employer will need to estimate other parameters, such as the length of the arc and the distance between the arc and the employee, because such parameters vary widely.
| 1. Standard for Electrical Safety Requirements for Employee Workplaces, NFPA 70E-2012, Annex D, “Sample Calculation of Flash Protection Boundary.” |
|---|
| 2. Doughty, T.E., Neal, T.E., and Floyd II, H.L., “Predicting Incident Energy to Better Manage the Electric Arc Hazard on 600 V Power Distribution Systems,” Record of Conference Papers IEEE IAS 45th Annual Petroleum and Chemical Industry Conference, September 28—30, 1998. |
| 3. Guide for Performing Arc-Flash Hazard Calculations, IEEE Std 1584-2002, 1584a--2004 (Amendment 1 to IEEE Std 1584-2002), and 1584b-2011 (Amendment 2: Changes to Clause 4 of IEEE Std 1584-2002). * |
| 4. ARCPRO, a commercially available software program developed by Kinectrics, Toronto, ON, CA. |
| * This appendix refers to IEEE Std 1584-2002 with both amendments as IEEE Std 1584b-2011. |
The amount of heat energy calculated by any of the methods is approximatelyinversely proportional to the square of the distance between the employee and the arc. In other words, if the employee is very close to the arc, the heat energy is very high; but if the employee is just a few more centimeters away, the heat energy drops substantially. Thus, estimating the distance from the arc to the employee is key to protecting employees.
The employer must select a method of estimating incident heat energy that provides a reasonable estimate of incident heat energy for the exposure involved. Table 3 shows which methods provide reasonable estimates for various exposures.
| Incident-energy calculation method | 600 V and Less 2 | 601 V to 15 kV 2 | More than 15 kV | ||||||
|---|---|---|---|---|---|---|---|---|---|
| 1Φ | 3Φa | 3Φb | 1Φ | 3Φa | 3Φb | 1Φ | 3Φa | 3Φb | |
| NFPA 70E-2012 Annex D (Lee equation) | Y-C | Y | N | Y-C | Y-C | N | N 3 | N 3 | N 3 |
| Doughty, Neal, and Floyd | Y-C | Y | Y | N | N | N | N | N | N |
| IEEE Std 1584b-2011 | Y | Y | Y | Y | Y | Y | N | N | N |
| ARCPRO | Y | N | N | Y | N | N | Y | Y 4 | Y 4 |
| Key: | |||||||||
| 1Φ: Single-phase arc in open air | |||||||||
| 3Φa: Three-phase arc in open air | |||||||||
| 3Φb: Three-phase arc in an enclosure (box) | |||||||||
| Y: Acceptable; produces a reasonable estimate of incident heat energy from this type of electric arc | |||||||||
| N: Not acceptable; does not produce a reasonable estimate of incident heat energy from this type of electric arc | |||||||||
| Y-C: Acceptable; produces a reasonable, but conservative, estimate of incident heat energy from this type of electric arc. | |||||||||
| Notes: 1 Although the Occupational Safety and Health Administration will consider these methods reasonable for enforcement purposes when employers use the methods in accordance with this table, employers should be aware that the listed methods do not necessarily result in estimates that will provide full protection from internal faults in transformers and similar equipment or from arcs in underground manholes or vaults. | |||||||||
| 2 At these voltages, the presumption is that the arc is three-phase unless the employer can demonstrate that only one phase is present or that the spacing of the phases is sufficient to prevent a multiphase arc from occurring. | |||||||||
| 3 Although the Occupational Safety and Health Administration will consider this method acceptable for purposes of assessing whether incident energy exceeds 2.0 cal/cm 2 , the results at voltages of more than 15 kilovolts are extremely conservative and unrealistic. | |||||||||
| 4 The Occupational Safety and Health Administration will deem the results of this method reasonable when the employer adjusts them using the conversion factors for three-phase arcs in open air or in an enclosure, as indicated in the program's instructions. |
Selecting a reasonable distance from the employee to the arc. In estimating available heat energy, the employer must make some reasonable assumptions about how far the employee will be from the electric arc. Table 4 lists reasonable distances from the employee to the electric arc. The distances in Table 4 are consistent with national consensus standards, such as the Institute of Electrical and Electronic Engineers' National Electrical Safety Code, ANSI/IEEE C2-2012, and IEEE Guide for Performing Arc-Flash Hazard Calculations, IEEE Std 1584b-2011. The employer is free to use other reasonable distances, but must consider equipment enclosure size and the working distance to the employee in selecting a distance from the employee to the arc. The Occupational Safety and Health Administration will consider a distance reasonable when the employer bases it on equipment size and working distance.
| Class of equipment | Single-phase arc mm (inches) | Three-phase arc mm (inches) |
|---|---|---|
| Cable | NA * | 455 (18) |
| Low voltage MCCs and panelboards | NA | 455 (18) |
| Low-voltage switchgear | NA | 610 (24) |
| 5-kV switchgear | NA | 910 (36) |
| 15-kV switchgear | NA | 910 (36) |
| Single conductors in air (up to 46 kilovolts), work with rubber insulating gloves | 380 (15) | NA |
| Single conductors in air, work with live-line tools and live-line barehand work | MAD−(2 × kV × 2.54) (MAD−(2 × kV /10)) † | NA |
| * NA = not applicable. | ||
| † The terms in this equation are: | ||
| MAD = The applicable minimum approach distance, and | ||
| kV = The system voltage in kilovolts. |
Selecting a reasonable arc gap. For a single-phase arc in air, the electric arc will almost always occur when an energized conductor approaches too close to ground. Thus, an employer can determine the arc gap, or arc length, for these exposures by the dielectric strength of air and the voltage on the line. The dielectric strength of air is approximately 10 kilovolts for every 25.4 millimeters (1 inch). For example, at 50 kilovolts, the arc gap would be 50 ÷ 10 × 25.4 (or 50 × 2.54), which equals 127 millimeters (5 inches).
For three-phase arcs in open air and in enclosures, the arc gap will generally be dependent on the spacing between parts energized at different electrical potentials. Documents such as IEEE Std 1584b-2011 provide information on these distances. Employers may select a reasonable arc gap from Table 5, or they may select any other reasonable arc gap based on sparkover distance or on the spacing between (1) live parts at different potentials or (2) live parts and grounded parts (for example, bus or conductor spacings in equipment). In any event, the employer must use an estimate that reasonably resembles the actual exposures faced by the employee.
| Class of equipment | Single-phase arc mm (inches) | Three-phase arc mm 1 (inches) |
|---|---|---|
| Cable | NA 2 | 13 (0.5) |
| Low voltage MCCs and panelboards | NA | 25 (1.0) |
| Low-voltage switchgear | NA | 32 (1.25) |
| 5-kV switchgear | NA | 104 (4.0) |
| 15-kV switchgear | NA | 152 (6.0) |
| Single conductors in air, 15 kV and less | 51 (2.0) | Phase conductor spacings. |
| Single conductor in air, more than 15 kV | Voltage in kV × 2.54 | |
| (Voltage in kV × 0.1), but no less than 51 mm (2 inches) | Phase conductor spacings. | |
| 1 Source: IEEE Std 1584b-2011. | ||
| 2 NA = not applicable. |
Making estimates over multiple system areas. The employer need not estimate the heat-energy exposure for every job task performed by each employee. Paragraph (g)(2) of § 1926.960 permits the employer to make broad estimates that cover multiple system areas provided that: (1) The employer uses reasonable assumptions about the energy-exposure distribution throughout the system, and (2) the estimates represent the maximum exposure for those areas. For example, the employer can use the maximum fault current and clearing time to cover several system areas at once.
Incident heat energy for single-phase-to-ground exposures. Table 6 and Table 7 provide incident heat energy levels for open-air, phase-to-ground electric-arc exposures typical for overhead systems. 2 Table 6 presents estimates of available energy for employees using rubber insulating gloves to perform work on overhead systems operating at 4 to 46 kilovolts. The table assumes that the employee will be 380 millimeters (15 inches) from the electric arc, which is a reasonable estimate for rubber insulating glove work. Table 6 also assumes that the arc length equals the sparkover distance for the maximum transient overvoltage of each voltage range. 3 To use the table, an employer would use the voltage, maximum fault current, and maximum clearing time for a system area and, using the appropriate voltage range and fault-current and clearing-time values corresponding to the next higher values listed in the table, select the appropriate heat energy (4, 5, 8, or 12 cal/cm 2 ) from the table. For example, an employer might have a 12,470-volt power line supplying a system area. The power line can supply a maximum fault current of 8 kiloamperes with a maximum clearing time of 10 cycles. For rubber glove work, this system falls in the 4.0-to-15.0-kilovolt range; the next-higher fault current is 10 kA (the second row in that voltage range); and the clearing time is under 18 cycles (the first column to the right of the fault current column). Thus, the available heat energy for this part of the system will be 4 cal/cm 2 or less (from the column heading), and the employer could select protection with a 5-cal/cm 2 rating to meet § 1926.960(g)(5). Alternatively, an employer could select a base incident-energy value and ensure that the clearing times for each voltage range and fault current listed in the table do not exceed the corresponding clearing time specified in the table. For example, an employer that provides employees with arc-flash protective equipment rated at 8 cal/cm 2 can use the table to determine if any system area exceeds 8 cal/cm 2 by checking the clearing time for the highest fault current for each voltage range and ensuring that the clearing times do not exceed the values specified in the 8-cal/cm 2 column in the table.
2 The Occupational Safety and Health Administration used metric values to calculate the clearing times in Table 6 and Table 7. An employer may use English units to calculate clearing times instead even though the results will differ slightly.
3 The Occupational Safety and Health Administration based this assumption, which is more conservative than the arc length specified in Table 5, on Table 410-2 of the 2012 NESC.
4 The dielectric strength of air is about 10 kilovolts for every 25.4 millimeters (1 inch). Thus, the employer can estimate the arc length in millimeters to be the phase-to-ground voltage in kilovolts multiplied by 2.54 (or voltage (in kilovolts) × 2.54).
The employer will need to use other methods for estimating available heat energy in situations not addressed by Table 6 or Table 7. The calculation methods listed in Table 2 and the guidance provided in Table 3 will help employers do this. For example, employers can use IEEE Std 1584b-2011 to estimate the available heat energy (and to select appropriate protective equipment) for many specific conditions, including lower-voltage, phase-to-phase arc, and enclosed arc exposures.
| Voltage range (kV) ** | Fault current (kA) | Maximum clearing time (cycles) | |||
|---|---|---|---|---|---|
| 4 cal/cm 2 | 5 cal/cm 2 | 8 cal/cm 2 | 12 cal/cm 2 | ||
| 4.0 to 15.0 | 5 | 46 | 58 | 92 | 138 |
| 10 | 18 | 22 | 36 | 54 | |
| 15 | 10 | 12 | 20 | 30 | |
| 20 | 6 | 8 | 13 | 19 | |
| 15.1 to 25.0 | 5 | 28 | 34 | 55 | 83 |
| 10 | 11 | 14 | 23 | 34 | |
| 15 | 7 | 8 | 13 | 20 | |
| 20 | 4 | 5 | 9 | 13 | |
| 25.1 to 36.0 | 5 | 21 | 26 | 42 | 62 |
| 10 | 9 | 11 | 18 | 26 | |
| 15 | 5 | 6 | 10 | 16 | |
| 20 | 4 | 4 | 7 | 11 | |
| 36.1 to 46.0 | 5 | 16 | 20 | 32 | 48 |
| 10 | 7 | 9 | 14 | 21 | |
| 15 | 4 | 5 | 8 | 13 | |
| 20 | 3 | 4 | 6 | 9 | |
| Notes: | |||||
| * This table is for open-air, phase-to-ground electric-arc exposures. It is not for phase-to-phase arcs or enclosed arcs (arc in a box). | |||||
| † The table assumes that the employee will be 380 mm (15 in.) from the electric arc. The table also assumes the arc length to be the sparkover distance for the maximum transient overvoltage of each voltage range (see Appendix B to this subpart), as follows: | |||||
| 4.0 to 15.0 kV 51 mm (2 in.) | |||||
| 15.1 to 25.0 kV 102 mm (4 in.) | |||||
| 25.1 to 36.0 kV 152 mm (6 in.) | |||||
| 36.1 to 46.0 kV 229 mm (9 in.) | |||||
| ‡ The Occupational Safety and Health Administration calculated the values in this table using the ARCPRO method listed in Table 2. | |||||
| ** The voltage range is the phase-to-phase system voltage. |
| Voltage range (kV) ** | Fault current (kA) | Maximum clearing time (cycles) | |||
|---|---|---|---|---|---|
| 4 cal/cm 2 | 5 cal/cm 2 | 8 cal/cm 2 | 12 cal/cm 2 | ||
| 4.0 to 15.0 | 5 | 197 | 246 | 394 | 591 |
| 10 | 73 | 92 | 147 | 220 | |
| 15 | 39 | 49 | 78 | 117 | |
| 20 | 24 | 31 | 49 | 73 | |
| 15.1 to 25.0 | 5 | 197 | 246 | 394 | 591 |
| 10 | 75 | 94 | 150 | 225 | |
| 15 | 41 | 51 | 82 | 122 | |
| 20 | 26 | 33 | 52 | 78 | |
| 25.1 to 36.0 | 5 | 138 | 172 | 275 | 413 |
| 10 | 53 | 66 | 106 | 159 | |
| 15 | 30 | 37 | 59 | 89 | |
| 20 | 19 | 24 | 38 | 58 | |
| 36.1 to 46.0 | 5 | 129 | 161 | 257 | 386 |
| 10 | 51 | 64 | 102 | 154 | |
| 15 | 29 | 36 | 58 | 87 | |
| 20 | 19 | 24 | 38 | 57 | |
| 46.1 to 72.5 | 20 | 18 | 23 | 36 | 55 |
| 30 | 10 | 13 | 20 | 30 | |
| 40 | 6 | 8 | 13 | 19 | |
| 50 | 4 | 6 | 9 | 13 | |
| 72.6 to 121.0 | 20 | 10 | 12 | 20 | 30 |
| 30 | 6 | 7 | 11 | 17 | |
| 40 | 4 | 5 | 7 | 11 | |
| 50 | 3 | 3 | 5 | 8 | |
| 121.1 to 145.0 | 20 | 12 | 15 | 24 | 35 |
| 30 | 7 | 9 | 15 | 22 | |
| 40 | 5 | 6 | 10 | 15 | |
| 50 | 4 | 5 | 8 | 11 | |
| 145.1 to 169.0 | 20 | 12 | 15 | 24 | 36 |
| 30 | 7 | 9 | 15 | 22 | |
| 40 | 5 | 7 | 10 | 16 | |
| 50 | 4 | 5 | 8 | 12 | |
| 169.1 to 242.0 | 20 | 13 | 17 | 27 | 40 |
| 30 | 8 | 10 | 17 | 25 | |
| 40 | 6 | 7 | 12 | 17 | |
| 50 | 4 | 5 | 9 | 13 | |
| 242.1 to 362.0 | 20 | 25 | 32 | 51 | 76 |
| 30 | 16 | 19 | 31 | 47 | |
| 40 | 11 | 14 | 22 | 33 | |
| 50 | 8 | 10 | 16 | 25 | |
| 362.1 to 420.0 | 20 | 12 | 15 | 25 | 37 |
| 30 | 8 | 10 | 15 | 23 | |
| 40 | 5 | 7 | 11 | 16 | |
| 50 | 4 | 5 | 8 | 12 | |
| 420.1 to 550.0 | 20 | 23 | 29 | 47 | 70 |
| 30 | 14 | 18 | 29 | 43 | |
| 40 | 10 | 13 | 20 | 30 | |
| 50 | 8 | 9 | 15 | 23 | |
| 550.1 to 800.0 | 20 | 25 | 31 | 50 | 75 |
| 30 | 15 | 19 | 31 | 46 | |
| 40 | 11 | 13 | 21 | 32 | |
| 50 | 8 | 10 | 16 | 24 | |
| Notes: | |||||
| * This table is for open-air, phase-to-ground electric-arc exposures. It is not for phase-to-phase arcs or enclosed arcs (arc in a box). | |||||
| † The table assumes the arc length to be the sparkover distance for the maximum phase-to-ground voltage of each voltage range (see Appendix B to this subpart). The table also assumes that the employee will be the minimum approach distance minus twice the arc length from the electric arc. | |||||
| ‡ The Occupational Safety and Health Administration calculated the values in this table using the ARCPRO method listed in Table 2. | |||||
| # For voltages of more than 72.6 kV, employers may use this table only when the minimum approach distance established under § 1926.960(c)(1) is greater than or equal to the following values: | |||||
| 72.6 to 121.0 kV 1.02 m | |||||
| 121.1 to 145.0 kV 1.16 m | |||||
| 145.1 to 169.0 kV 1.30 m | |||||
| 169.1 to 242.0 kV 1.72 m | |||||
| 242.1 to 362.0 kV 2.76 m | |||||
| 362.1 to 420.0 kV 2.50 m | |||||
| 420.1 to 550.0 kV 3.62 m | |||||
| 550.1 to 800.0 kV 4.83 m | |||||
| ** The voltage range is the phase-to-phase system voltage. |
B. Selecting Protective Clothing and Other Protective Equipment
Paragraph (g)(5) of § 1926.960 requires employers, in certain situations, to select protective clothing and other protective equipment with an arc rating that is greater than or equal to the incident heat energy estimated under § 1926.960(g)(2). Based on laboratory testing required by ASTM F1506-10a, the expectation is that protective clothing with an arc rating equal to the estimated incident heat energy will be capable of preventing second-degree burn injury to an employee exposed to that incident heat energy from an electric arc. Note that actual electric-arc exposures may be more or less severe than the estimated value because of factors such as arc movement, arc length, arcing from reclosing of the system, secondary fires or explosions, and weather conditions. Additionally, for arc rating based on the fabric's arc thermal performance value 5 (ATPV), a worker exposed to incident energy at the arc rating has a 50-percent chance of just barely receiving a second-degree burn. Therefore, it is possible (although not likely) that an employee will sustain a second-degree (or worse) burn wearing clothing conforming to § 1926.960(g)(5) under certain circumstances. However, reasonable employer estimates and maintaining appropriate minimum approach distances for employees should limit burns to relatively small burns that just barely extend beyond the epidermis (that is, just barely a second-degree burn). Consequently, protective clothing and other protective equipment meeting § 1926.960(g)(5) will provide an appropriate degree of protection for an employee exposed to electric-arc hazards.
5 ASTM F1506-10a defines “arc thermal performance value” as “the incident energy on a material or a multilayer system of materials that results in a 50% probability that sufficient heat transfer through the tested specimen is predicted to cause the onset of a second-degree skin burn injury based on the Stoll [footnote] curve, cal/cm 2.” The footnote to this definition reads: “Derived from: Stoll, A.M., and Chianta, M.A., `Method and Rating System for Evaluations of Thermal Protection,' Aerospace Medicine, Vol 40, 1969, pp. 1232-1238 and Stoll A.M., and Chianta, M.A., `Heat Transfer through Fabrics as Related to Thermal Injury,' Transactions—New York Academy of Sciences, Vol 33(7), Nov. 1971, pp. 649-670.”
Paragraph (g)(5) of § 1926.960 does not require arc-rated protection for exposures of 2 cal/cm 2 or less. Untreated cotton clothing will reduce a 2-cal/cm 2 exposure below the 1.2- to 1.5-cal/cm 2 level necessary to cause burn injury, and this material should not ignite at such low heat energy levels. Although § 1926.960(g)(5) does not require clothing to have an arc rating when exposures are 2 cal/cm 2 or less, § 1926.960(g)(4) requires the outer layer of clothing to be flame resistant under certain conditions, even when the estimated incident heat energy is less than 2 cal/cm 2, as discussed later in this appendix. Additionally, it is especially important to ensure that employees do not wear undergarments made from fabrics listed in the note to § 1926.960(g)(3) even when the outer layer is flame resistant or arc rated. These fabrics can melt or ignite easily when an electric arc occurs. Logos and name tags made from non-flame-resistant material can adversely affect the arc rating or the flame-resistant characteristics of arc-rated or flame-resistant clothing. Such logos and name tags may violate § 1926.960(g)(3), (g)(4), or (g)(5).
Paragraph (g)(5) of § 1926.960 requires that arc-rated protection cover the employee's entire body, with limited exceptions for the employee's hands, feet, face, and head. Paragraph (g)(5)(i) of § 1926.960 provides that arc-rated protection is not necessary for the employee's hands under the following conditions:
| For any estimated incident heat energy | When the employee is wearing rubber insulating gloves with protectors |
|---|---|
| If the estimated incident heat energy does not exceed 14 cal/cm 2 | When the employee is wearing heavy-duty leather work gloves with a weight of at least 407 gm/m 2 (12 oz/yd 2 ) |
Paragraph (g)(5)(ii) of § 1926.960 provides that arc-rated protection is not necessary for the employee's feet when the employee is wearing heavy-duty work shoes or boots. Finally, § 1926.960(g)(5)(iii), (g)(5)(iv), and (g)(5)(v) require arc-rated head and face protection as follows:
| Exposure | Minimum head and face protection | ||
|---|---|---|---|
| None * | Arc-rated faceshield with a minimum rating of 8 cal/cm 2 * | Arc-rated hood or faceshield with balaclava | |
| Single-phase, open air | 2-8 cal/cm 2 | 9-12 cal/cm 2 | 13 cal/ 2 or higher. † |
| Three-phase | 2-4 cal/cm 2 | 5-8 cal/cm 2 | 9 cal/cm 2 or higher. ‡ |
| * These ranges assume that employees are wearing hardhats meeting the specifications in § 1910.135 or § 1926.100(b)(2), as applicable. | |||
| † The arc rating must be a minimum of 4 cal/cm 2 less than the estimated incident energy. Note that § 1926.960(g)(5)(v) permits this type of head and face protection, with a minimum arc rating of 4 cal/cm 2 less than the estimated incident energy, at any incident energy level. | |||
| ‡ Note that § 1926.960(g)(5) permits this type of head and face protection at any incident energy level. |
IV. Protection Against Ignition
Paragraph (g)(3) of § 1926.960 prohibits clothing that could melt onto an employee's skin or that could ignite and continue to burn when exposed to flames or to the available heat energy estimated by the employer under § 1926.960(g)(2). Meltable fabrics, such as acetate, nylon, polyester, and polypropylene, even in blends, must be avoided. When these fibers melt, they can adhere to the skin, thereby transferring heat rapidly, exacerbating burns, and complicating treatment. These outcomes can result even if the meltable fabric is not directly next to the skin. The remainder of this section focuses on the prevention of ignition.
Paragraph (g)(5) of § 1926.960 generally requires protective clothing and other protective equipment with an arc rating greater than or equal to the employer's estimate of available heat energy. As explained earlier in this appendix, untreated cotton is usually acceptable for exposures of 2 cal/cm 2 or less. 6 If the exposure is greater than that, the employee generally must wear flame-resistant clothing with a suitable arc rating in accordance with § 1926.960(g)(4) and (g)(5). However, even if an employee is wearing a layer of flame-resistant clothing, there are circumstances under which flammable layers of clothing would be uncovered, and an electric arc could ignite them. For example, clothing ignition is possible if the employee is wearing flammable clothing under the flame-resistant clothing and the underlayer is uncovered because of an opening in the flame-resistant clothing. Thus, for purposes of § 1926.960(g)(3), it is important for the employer to consider the possibility of clothing ignition even when an employee is wearing flame-resistant clothing with a suitable arc rating.
6 See § 1926.960(g)(4)(i), (g)(4)(ii), and (g)(4)(iii) for conditions under which employees must wear flame-resistant clothing as the outer layer of clothing even when the incident heat energy does not exceed 2 cal/cm 2.
Under § 1926.960(g)(3), employees may not wear flammable clothing in conjunction with flame-resistant clothing if the flammable clothing poses an ignition hazard. 7 Although outer flame-resistant layers may not have openings that expose flammable inner layers, when an outer flame-resistant layer would be unable to resist breakopen, 8 the next (inner) layer must be flame-resistant if it could ignite.
7 Paragraph (g)(3) of § 1926.960 prohibits clothing that could ignite and continue to burn when exposed to the heat energy estimated under paragraph (g)(2) of that section.
8 Breakopen occurs when a hole, tear, or crack develops in the exposed fabric such that the fabric no longer effectively blocks incident heat energy.
Non-flame-resistant clothing can ignite even when the heat energy from an electric arc is insufficient to ignite the clothing. For example, nearby flames can ignite an employee's clothing; and, even in the absence of flames, electric arcs pose ignition hazards beyond the hazard of ignition from incident energy under certain conditions. In addition to requiring flame-resistant clothing when the estimated incident energy exceeds 2.0 cal/cm 2, § 1926.960(g)(4) requires flame-resistant clothing when: The employee is exposed to contact with energized circuit parts operating at more than 600 volts (§ 1926.960(g)(4)(i)), an electric arc could ignite flammable material in the work area that, in turn, could ignite the employee's clothing (§ 1926.960(g)(4)(ii)), and molten metal or electric arcs from faulted conductors in the work area could ignite the employee's clothing (§ 1926.960(g)(4)(iii)). For example, grounding conductors can become a source of heat energy if they cannot carry fault current without failure. The employer must consider these possible sources of electric arcs 9 in determining whether the employee's clothing could ignite under § 1926.960(g)(4)(iii).
9 Static wires and pole grounds are examples of grounding conductors that might not be capable of carrying fault current without failure. Grounds that can carry the maximum available fault current are not a concern, and employers need not consider such grounds a possible electric arc source.
I. Body Belts
Inspect body belts to ensure that:
A. The hardware has no cracks, nicks, distortion, or corrosion;
B. No loose or worn rivets are present;
C. The waist strap has no loose grommets;
D. The fastening straps are not 100-percent leather; and
E. No worn materials that could affect the safety of the user are present.
II. Positioning Straps
Inspect positioning straps to ensure that:
A. The warning center of the strap material is not exposed;
B. No cuts, burns, extra holes, or fraying of strap material is present;
C. Rivets are properly secured;
D. Straps are not 100-percent leather; and
E. Snaphooks do not have cracks, burns, or corrosion.
III. Climbers
Inspect pole and tree climbers to ensure that:
A. Gaffs are at least as long as the manufacturer's recommended minimums (generally 32 and 51 millimeters (1.25 and 2.0 inches) for pole and tree climbers, respectively, measured on the underside of the gaff);
B. Gaffs and leg irons are not fractured or cracked;
C. Stirrups and leg irons are free of excessive wear;
D. Gaffs are not loose;
E. Gaffs are free of deformation that could adversely affect use;
F. Gaffs are properly sharpened; and
G. There are no broken straps or buckles.
The references contained in this appendix provide information that can be helpful in understanding and complying with the requirements contained in Subpart V of this part. The national consensus standards referenced in this appendix contain detailed specifications that employers may follow in complying with the more performance-based requirements of Subpart V of this part. Except as specifically noted in Subpart V of this part, however, the Occupational Safety and Health Administration will not necessarily deem compliance with the national consensus standards to be compliance with the provisions of Subpart V of this part.
American National Standard for Vehicle-Mounted Elevating and Rotating Aerial Devices.
American National Standard Safety Requirements for Arboricultural Operations—Pruning, Trimming, Repairing, Maintaining, and Removing Trees, and Cutting Brush.
IEEE Guide on Terminology for Tools and Equipment to Be Used in Live Line Working.
Safety Standard for Conveyors and Related Equipment.
Standard Specification for Rubber Insulating Gloves.
Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies.
Standard Specification for Rubber Insulating Matting.
Standard Specification for Rubber Insulating Blankets.
Standard Specification for Rubber Insulating Covers.
Standard Specification for Rubber Insulating Line Hose.
Standard Specification for Rubber Insulating Sleeves.
Standard Specification for In-Service Care of Insulating Line Hose and Covers.
Standard Specification for In-Service Care of Insulating Blankets.
Standard Specification for In-Service Care of Insulating Gloves and Sleeves.
Standard Specification for Fiberglass-Reinforced Plastic (FRP) Rod and Tube Used in Live Line Tools.
Standard Test Methods and Specifications for Electrically Insulating Plastic Guard Equipment for Protection of Workers.
Standard Terminology Relating to Electrical Protective Equipment for Workers.
Standard Specifications for Temporary Protective Grounds to Be Used on De-energized Electric Power Lines and Equipment.
e1
Standard Specifications for Personal Climbing Equipment.
Standard Test Method for Acoustic Emission for Aerial Personnel Devices Without Supplemental Load Handling Attachments.
Standard Test Method for Determining Dielectric Strength of Dielectric Footwear.
Standard Specification for Dielectric Footwear.
Standard Guide for Visual Inspection of Electrical Protective Rubber Products.
Standard Test Method for Acoustic Emission Testing of Insulated and Non-Insulated Aerial Personnel Devices with Supplemental Load Handling Attachments.
Standard Specification for Insulated and Insulating Hand Tools.
Standard Performance Specification for Flame Resistant and Arc Rated Textile Materials for Wearing Apparel for Use by Electrical Workers Exposed to Momentary Electric Arc and Related Thermal Hazards.
Standard Specification for Structure-Mounted Insulating Work Platforms for Electrical Workers.
Standard Specification for Unused Polypropylene Rope with Special Electrical Properties.
Standard Specification for PVC Insulating Sheeting.
Standard Specification for High Voltage Detectors—Part 1 Capacitive Type to be Used for Voltages Exceeding 600 Volts AC.
ε
1
Standard Test Method for Acoustic Emission Testing of Insulated and Non-Insulated Digger Derricks.
Standard Specification for Clampstick Type Live Line Tools.
Standard Specification for Live Line and Measuring Telescoping Tools.
Standard Specification for Arc and Flame Resistant Rainwear.
Standard Test Method for Determining the Ignitability of Non-flame-Resistant Materials for Clothing by Electric Arc Exposure Method Using Mannequins.
Standard Test Method for Determining the Arc Rating of Materials for Clothing.
IEEE Standard Techniques for High-Voltage Testing
IEEE Standard Techniques for High-Voltage Testing.
IEEE Guide for Diagnostic Field Testing of Electric Power Apparatus—Part 1: Oil Filled Power Transformers, Regulators, and Reactors.
Guide for Safety in AC Substation Grounding.
The Authoritative Dictionary of IEEE Standards Terms Seventh Edition.
IEEE Guide for Maintenance Methods on Energized Power Lines.
IEEE Guide to the Installation of Overhead Transmission Line Conductors.
IEEE Guide for Cleaning Insulators.
IEEE Guide for Protective Grounding of Power Lines.
IEEE Guide for In-Service Use, Care, Maintenance, and Testing of Conductive Clothing for Use on Voltages up to 765 kV AC and ±750 kV DC.
IEEE Standard for Fall Protection for Utility Work.
IEEE Guide for Performing Arc-Flash Hazard Calculations.
National Electrical Safety Code.
Standard for Electrical Safety in the Workplace.
This subpart applies to the following types of material handling equipment: All rubber-tired, self-propelled scrapers, rubber-tired front-end loaders, rubber-tired dozers, wheel-type agricultural and industrial tractors, crawler tractors, crawler-type loaders, and motor graders, with or without attachments, that are used in construction work. This subpart also applies to compactors and rubber-tired skid-steer equipment, with or without attachments, manufactured after July 15, 2019, that are used in construction work. This subpart does not apply to sideboom pipelaying tractors.
ROPS removed for any reason, shall be remounted with equal quality, or better, bolts or welding as required for the original mounting.
Each ROPS shall have the following information permanently affixed to the structure:
model number, if any;
Any machine in use, equipped with rollover protective structures, shall be deemed in compliance with this section if it meets the rollover protective structure requirements of the State of California, the U.S. Army Corps of Engineers, or the Bureau of Reclamation of the U.S. Department of the Interior in effect on April 5, 1972. The requirements in effect are:
Construction Safety Orders, issued by the Department of Industrial Relations pursuant to Division 5, Labor Code, § 6312, State of California.
General Safety Requirements, EM-385-1-1 (March 1967).
Safety and Health Regulations for Construction. Part II (September 1971).
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 84 FR 21577, May 14, 2019]
This section prescribes minimum performance criteria for roll-over protective structures (ROPS) for rubber-tired self-propelled scrapers; rubber-tired front end loaders and rubber-tired dozers; crawler tractors and crawler-type loaders, motor graders, compactors, and rubber-tired skid steer equipment.
[84 FR 21578, May 14, 2019]
This section sets forth requirements for frames used to protect operators of wheel-type agricultural and industrial tractors used in construction work that will minimize the possibility of operator injury resulting from accidental upsets during normal operation. See paragraph (e) of this section for definitions of agricultural and industrial tractors.
For overhead protection requirements, see § 1926.1003.
[70 FR 76985, Dec. 29, 2005, as amended at 71 FR 41129, July 20, 2006; 84 FR 21578, May 14, 2019]
This section sets forth requirements for overhead protection used to protect operators of wheel-type agricultural and industrial tractors used in construction work that will minimize the possibility of operator injury resulting from overhead objects such as flying or falling objection, and from the cover itself in the event of accidental upset.
In the case of machines to which § 1926.604 (relating to site clearing) also applies, the overhead protection may be either the type of protection provided in § 1926.604, or the type of protection provided by this section.
[84 FR 21578, May 14, 2019]
This subpart applies to all stairways and ladders used in construction, alteration, repair (including painting and decorating), and demolition workplaces covered under 29 CFR part 1926, and also sets forth, in specified circumstances, when ladders and stairways are required to be provided. Additional requirements for ladders used on or with scaffolds are contained in subpart L—Scaffolds. This subpart does not apply to integral components of equipment covered by subpart CC. Subpart CC exclusively sets forth the circumstances when ladders and stairways must be provided on equipment covered by subpart CC.
Cleat means a ladder crosspiece of rectangular cross section placed on edge upon which a person may step while ascending or descending a ladder.
Double-cleat ladder means a ladder similar in construction to a single-cleat ladder, but with a center rail to allow simultaneous two-way traffic for employees ascending or descending.
Equivalent means alternative designs, materials, or methods that the employer can demonstrate will provide an equal or greater degree of safety for employees than the method or item specified in the standard.
Extension trestle ladder means a self-supporting portable ladder, adjustable in length, consisting of a trestle ladder base and a vertically adjustable extension section, with a suitable means for locking the ladders together.
Failure means load refusal, breakage, or separation of component parts. Load refusal is the point where the structural members lose their ability to carry the loads.
Fixed ladder means a ladder that cannot be readily moved or carried because it is an integral part of a building or structure. A side-step fixed ladder is a fixed ladder that requires a person getting off at the top to step to the side of the ladder side rails to reach the landing. A through fixed ladder is a fixed ladder that requires a person getting off at the top to step between the side rails of the ladder to reach the landing.
Handrail means a rail used to provide employees with a handhold for support.
Individual-rung/step ladders means ladders without a side rail or center rail support. Such ladders are made by mounting individual steps or rungs directly to the side or wall of the structure.
Job-made ladder means a ladder that is fabricated by employees, typically at the construction site, and is not commercially manufactured. This definition does not apply to any individual-rung/step ladders.
Ladder stand. A mobile fixed size self-supporting ladder consisting of a wide flat tread ladder in the form of stairs. The assenbly may include handrails.
Lower levels means those areas to which an employee can fall from a stairway or ladder. Such areas include ground levels, floors, roofs, ramps, runways, excavations, pits, tanks, material, water, equipment, and similar surfaces. It does not include the surface from which the employee falls.
Maximum intended load means the total load of all employees, equipment, tools, materials, transmitted loads, and other loads anticipated to be applied to a ladder component at any one time.
Nosing means that portion of a tread projecting beyond the face of the riser immediately below.
Point of access means all areas used by employees for work-related passage from one area or level to another. Such open areas include doorways, 1passageways, stairway openings, studded walls, and various other permanent or temporary openings used for such travel.
Portable ladder means a ladder that can be readily moved or carried.
Riser height means the vertical distance from the top of a tread to the top of the next higher tread or platform/landing or the distance from the top of a platform/landing to the top of the next higher tread or platform/landing.
Side-step fixed ladder. See “Fixed ladder.”
Single-cleat ladder means a ladder consisting of a pair of side rails, connected together by cleats, rungs, or steps.
Single-rail ladder means a portable ladder with rungs, cleats, or steps mounted on a single rail instead of the normal two rails used on most other ladders.
Spiral stairway means a series of steps attached to a vertical pole and progressing upward in a winding fashion within a cylindrical space.
Stairrail system means a vertical barrier erected along the unprotected sides and edges of a stariway to prevent employees from falling to lower levels. The top surface of a stairrail system may also be a “handrail.”
Step stool (ladder type) means a self-supporting, foldable, portable ladder, nonadjustable in length, 32 inches or less in overall size, with flat steps and without a pail shelf, designed to be climbed on the ladder top cap as well as all steps. The side rails may continue above the top cap.
Through fixed ladder. See “Fixed ladder.”
Tread depth means the horizontal distance from front to back of a tread (excluding nosing, if any).
Unprotected sides and edges means any side or edge (except at entrances to points of access) of a stairway where there is no stairrail system or wall 36 inches (.9 m) or more in height, and any side or edge (except at entrances to points of access) of a stairway landing, or ladder platform where there is no wall or guardrail system 39 inches (1 m) or more in height.
[55 FR 47687, Nov. 14, 1990; 56 FR 2585, Jan. 23, 1991, as amended at 58 FR 35184, June 30, 1993; 75 FR 48135, Aug. 9, 2010]
The following requirements apply to all stairways as indicated:
The following requirements apply to all stairways as indicated:
The following requirements apply to all stairways as indicated:
[55 FR 47687, Nov. 14, 1990; 56 FR 2585, Jan. 23, 1991; 56 FR 5061, Feb. 7, 1991; 56 FR 41794, Aug. 23, 1991]
The following requirements apply to all ladders as indicated, including job-made ladders.
At least four times the maximum intended load, except that each extra-heavy-duty type 1A metal or plastic ladder shall sustain at least 3.3 times the maximum intended load. The ability of a ladder to sustain the loads indicated in this paragraph shall be determined by applying or transmitting the requisite load to the ladder in a downward vertical direction. Ladders built and tested in conformance with the applicable provisions of appendix A of this subpart will be deemed to meet this requirement.
At least four times the maximum intended load, except that each extra-heavy-duty type 1A metal or plastic ladders shall sustain at least 3.3 times the maximum intended load. The ability of a ladder to sustain the loads indicated in this paragraph shall be determined by applying or transmitting the requisite load to the ladder in a downward vertical direction when the ladder is placed at an angle of 75 1/2 degrees from the horizontal. Ladders built and tested in conformance with the applicable provisions of appendix A will be deemed to meet this requirement.
At least two loads of 250 pounds (114 kg) each, concentrated between any two consecutive attachments (the number and position of additional concentrated loads of 250 pounds (114 kg) each, determined from anticipated usage of the ladder, shall also be included), plus anticipated loads caused by ice buildup, winds, rigging, and impact loads resulting from the use of ladder safety devices. Each step or rung shall be capable of supporting a single concentrated load of at least 250 pounds (114 kg) applied in the middle of the step or rung. Ladders built in conformance with the applicable provisions of appendix A will be deemed to meet this requirement.
The following requirements apply to the use of all ladders, including job-made ladders, except as otherwise indicated:
[55 FR 47687, Nov. 14, 1990; 56 FR 2585, Jan. 23, 1991, as amended at 56 FR 41794, Aug. 23, 1991; 79 FR 20743, Apr. 11, 2014]
The following training provisions clarify the requirements of § 1926.21(b)(2), regarding the hazards addressed in subpart X.
This appendix serves as a non-mandatory guideline to assist employers in complying with the ladder loading and strength requirements of § 1926.1053(a)(1). A ladder designed and built in accordance with the applicable national consensus standards, as set forth below, will be considered to meet the requirements of § 1926.1053(a)(1):
• Manufactured portable wood ladders: American National Standards Institute (ANSI) A14.1-1982—American National Standard for Ladders-Portable Wood-Safety Requirements.
• Manufactured portable metal ladders: ANSI A14.2-1982—American National Standard for Ladders—Portable Metal-Safety Requirements.
• Manufactured fixed ladders: ANSI A14.3-1984—American National Standard for Ladders-Fixed-Safety Requirements.
• Job-made ladders: ANSI A14.4-1979—Safety Requirements for Job-Made Ladders.
• Plastic ladders: ANSI A14.5-1982—American National Standard for Ladders-Portable Reinforced Plastic-Safety Requirements.
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31432, June 20, 1996]
[61 FR 31433, June 20, 1996]
This section regulates asbestos exposure in all work as defined in 29 CFR 1910.12(b), including but not limited to the following:
Aggressive method means removal or disturbance of building material by sanding, abrading, grinding or other method that breaks, crumbles, or disintegrates intact ACM.
Amended water means water to which surfactant (wetting agent) has been added to increase the ability of the liquid to penetrate ACM.
Asbestos includes chrysotile, amosite, crocidolite, tremolite asbestos, anthophyllite asbestos, actinolite asbestos, and any of these minerals that has been chemically treated and/or altered. For purposes of this standard, “asbestos” includes PACM, as defined below.
Asbestos-containing material (ACM), means any material containing more than one percent asbestos.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person authorized by the employer and required by work duties to be present in regulated areas.
Building/facility owner is the legal entity, including a lessee, which exercises control over management and record keeping functions relating to a building and/or facility in which activities covered by this standard take place.
Certified Industrial Hygienist (CIH) means one certified in the practice of industrial hygiene by the American Board of Industrial Hygiene.
Class I asbestos work means activities involving the removal of TSI and surfacing ACM and PACM.
Class II asbestos work means activities involving the removal of ACM which is not thermal system insulation or surfacing material. This includes, but is not limited to, the removal of asbestos-containing wallboard, floor tile and sheeting, roofing and siding shingles, and construction mastics.
Class III asbestos work means repair and maintenance operations, where “ACM”, including TSI and surfacing ACM and PACM, is likely to be disturbed.
Class IV asbestos work means maintenance and custodial activities during which employees contact but do not disturb ACM or PACM and activities to clean up dust, waste and debris resulting from Class I, II, and III activities.
Clean room means an uncontaminated room having facilities for the storage of employees' street clothing and uncontaminated materials and equipment.
Closely resemble means that the major workplace conditions which have contributed to the levels of historic asbestos exposure, are no more protective than conditions of the current workplace.
Competent person means, in addition to the definition in 29 CFR 1926.32 (f), one who is capable of identifying existing asbestos hazards in the workplace and selecting the appropriate control strategy for asbestos exposure, who has the authority to take prompt corrective measures to eliminate them, as specified in 29 CFR 1926.32(f): in addition, for Class I and Class II work who is specially trained in a training course which meets the criteria of EPA's Model Accreditation Plan (40 CFR part 763) for supervisor, or its equivalent and, for Class III and Class IV work, who is trained in a manner consistent with EPA requirements for training of local education agency maintenance and custodial staff as set forth at 40 CFR 763.92 (a)(2).
Critical barrier means one or more layers of plastic sealed over all openings into a work area or any other similarly placed physical barrier sufficient to prevent airborne asbestos in a work area from migrating to an adjacent area.
Decontamination area means an enclosed area adjacent and connected to the regulated area and consisting of an equipment room, shower area, and clean room, which is used for the decontamination of workers, materials, and equipment that are contaminated with asbestos.
Demolition means the wrecking or taking out of any load-supporting structural member and any related razing, removing, or stripping of asbestos products.
Director means the Director, National Institute for Occupational Safety and Health, U.S. Department of Health and Human Services, or designee.
Disturbance means activities that disrupt the matrix of ACM or PACM, crumble or pulverize ACM or PACM, or generate visible debris from ACM or PACM. In no event shall the amount of ACM or PACM so disturbed exceed that which can be contained in one glove bag or waste bag which shall not exceed 60 inches in length and width.
Employee exposure means that exposure to airborne asbestos that would occur if the employee were not using respiratory protective equipment.
Equipment room ( change room ) means a contaminated room located within the decontamination area that is supplied with impermeable bags or containers for the disposal of contaminated protective clothing and equipment.
Fiber means a particulate form of asbestos, 5 micrometers or longer, with a length-to-diameter ratio of at least 3 to 1.
Glovebag means not more than a 60 × 60 inch impervious plastic bag-like enclosure affixed around an asbestos-containing material, with glove-like appendages through which material and tools may be handled.
High-efficiency particulate air (HEPA) filter means a filter capable of trapping and retaining at least 99.97 percent of all mono-dispersed particles of 0.3 micrometers in diameter.
Homogeneous area means an area of surfacing material or thermal system insulation that is uniform in color and texture.
Industrial hygienist means a professional qualified by education, training, and experience to anticipate, recognize, evaluate and develop controls for occupational health hazards.
Intact means that the ACM has not crumbled, been pulverized, or otherwise deteriorated so that the asbestos is no longer likely to be bound with its matrix.
Modification for purposes of paragraph (g)(6)(ii), means a changed or altered procedure, material or component of a control system, which replaces a procedure, material or component of a required system. Omitting a procedure or component, or reducing or diminishing the stringency or strength of a material or component of the control system is not a “modification” for purposes of paragraph (g)(6) of this section.
Negative Initial Exposure Assessment means a demonstration by the employer, which complies with the criteria in paragraph (f)(2)(iii) of this section, that employee exposure during an operation is expected to be consistently below the PELs.
PACM means “presumed asbestos containing material”.
Presumed Asbestos Containing Material means thermal system insulation and surfacing material found in buildings constructed no later than 1980. The designation of a material as “PACM” may be rebutted pursuant to paragraph (k)(5) of this section.
Project Designer means a person who has successfully completed the training requirements for an abatement project designer established by 40 U.S.C. 763.90(g).
Regulated area means: an area established by the employer to demarcate areas where Class I, II, and III asbestos work is conducted, and any adjoining area where debris and waste from such asbestos work accumulate; and a work area within which airborne concentrations of asbestos, exceed or there is a reasonable possibility they may exceed the permissible exposure limit. Requirements for regulated areas are set out in paragraph (e) of this section.
Removal means all operations where ACM and/or PACM is taken out or stripped from structures or substrates, and includes demolition operations.
Renovation means the modifying of any existing structure, or portion thereof.
Repair means overhauling, rebuilding, reconstructing, or reconditioning of structures or substrates, including encapsulation or other repair of ACM or PACM attached to structures or substrates.
Surfacing material means material that is sprayed, troweled-on or otherwise applied to surfaces (such as acoustical plaster on ceilings and fireproofing materials on structural members, or other materials on surfaces for acoustical, fireproofing, and other purposes).
Surfacing ACM means surfacing material which contains more than 1% asbestos.
Thermal system insulation (TSI) means ACM applied to pipes, fittings, boilers, breeching, tanks, ducts or other structural components to prevent heat loss or gain.
Thermal system insulation ACM is thermal system insulation which contains more than 1% asbestos.
The employer shall ensure that no employee is exposed to an airborne concentration of asbestos in excess of 0.1 fiber per cubic centimeter of air as an eight (8) hour time-weighted average (TWA), as determined by the method prescribed in appendix A to this section, or by an equivalent method.
The employer shall ensure that no employee is exposed to an airborne concentration of asbestos in excess of 1.0 fiber per cubic centimeter of air (1 f/cc) as averaged over a sampling period of thirty (30) minutes, as determined by the method prescribed in appendix A to this section, or by an equivalent method.
The regulated area shall be demarcated in any manner that minimizes the number of persons within the area and protects persons outside the area from exposure to airborne asbestos. Where critical barriers or negative pressure enclosures are used, they may demarcate the regulated area. Signs shall be provided and displayed pursuant to the requirements of paragraph (k)(7) of this section.
Access to regulated areas shall be limited to authorized persons and to persons authorized by the Act or regulations issued pursuant thereto.
All persons entering a regulated area where employees are required pursuant to paragraph (h)(1) of this section to wear respirators shall be supplied with a respirator selected in accordance with paragraph (h)(3) of this section.
The employer shall ensure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in the regulated area.
The employer shall ensure that all asbestos work performed within regulated areas is supervised by a competent person, as defined in paragraph (b) of this section. The duties of the competent person are set out in paragraph (o) of this section.
Unless a negative exposure assessment has been made pursuant to paragraph (f)(2)(iii) of this section, the initial exposure assessment shall, if feasible, be based on monitoring conducted pursuant to paragraph (f)(1)(iii) of this section. The assessment shall take into consideration both the monitoring results and all observations, information or calculations which indicate employee exposure to asbestos, including any previous monitoring conducted in the workplace, or of the operations of the employer which indicate the levels of airborne asbestos likely to be encountered on the job. For Class I asbestos work, until the employer conducts exposure monitoring and documents that employees on that job will not be exposed in excess of the PELs, or otherwise makes a negative exposure assessment pursuant to paragraph (f)(2)(iii) of this section, the employer shall presume that employees are exposed in excess of the TWA and excursion limit.
For any one specific asbestos job which will be performed by employees who have been trained in compliance with the standard, the employer may demonstrate that employee exposures will be below the PELs by data which conform to the following criteria;
The employer shall conduct daily monitoring that is representative of the exposure of each employee who is assigned to work within a regulated area who is performing Class I or II work, unless the employer pursuant to (f)(2)(iii) of this section, has made a negative exposure assessment for the entire operation.
When all employees required to be monitored daily are equipped with supplied-air respirators operated in the pressure demand mode, or other positive pressure mode, the employer may dispense with the daily monitoring required by this paragraph. However, employees performing Class I work using a control method which is not listed in paragraph (g)(4)(i), (ii), or (iii) of this section or using a modification of a listed control method, shall continue to be monitored daily even if they are equipped with supplied-air respirators.
Notwithstanding the provisions of paragraph (f) (2) and (3), and (f)(4) of this section, the employer shall institute the exposure monitoring required under paragraph (f)(3) of this section whenever there has been a change in process, control equipment, personnel or work practices that may result in new or additional exposures above the permissible exposure limit and/or excursion limit or when the employer has any reason to suspect that a change may result in new or additional exposures above the permissible exposure limit and/or excursion limit. Such additional monitoring is required regardless of whether a “negative exposure assessment” was previously produced for a specific job.
The employer must, as soon as possible but no later than 5 working days after the receipt of the results of any monitoring performed under this section, notify each affected employee of these results either individually in writing or by posting the results in an appropriate location that is accessible to employees.
The following work practices and engineering controls shall not be used for work related to asbestos or for work which disturbs ACM or PACM, regardless of measured levels of asbestos exposure or the results of initial exposure assessments:
In addition to the provisions of paragraphs (g) (1) and (2) of this section, the following engineering controls and work practices and procedures shall be used.
In addition, Class I asbestos work shall be performed using one or more of the following control methods pursuant to the limitations stated below:
NPE systems may be used where the configuration of the work area does not make the erection of the enclosure infeasible, with the following specifications and work practices.
Negative pressure glove bag systems may be used to remove ACM or PACM from piping.
In addition to specifications for glove bag systems above, negative pressure glove bag systems shall attach HEPA vacuum systems or other devices to bag to prevent collapse during removal.
Negative pressure glove boxes may be used to remove ACM or PACM from pipe runs with the following specifications and work practices.
filtration system shall be used to maintain pressure barrier in box.
A water spray process system may be used for removal of ACM and PACM from cold line piping if, employees carrying out such process have completed a 40-hour separate training course in its use, in addition to training required for employees performing Class I work. The system shall meet the following specifications and shall be performed by employees using the following work practices.
degree water spray, delivered through nozzles supplied by a high pressure separate water line, shall be formed around the piping.
Class I work may be performed using a control method which is not referenced in paragraph (g)(5) of this section, or which modifies a control method referenced in paragraph (g)(5)of this section, if the following provisions are complied with:
Class II asbestos work shall also be performed by complying with the work practices and controls designated for each type of asbestos work to be performed, set out in this paragraph. Where more than one control method may be used for a type of asbestos work, the employer may choose one or a combination of designated control methods. Class II work also may be performed using a method allowed for Class I work, except that glove bags and glove boxes are allowed if they fully enclose the Class II material to be removed.
Instead of the work practices and controls listed in paragraph (g)(8) (i) through (v) of this section, the employer may use different or modified engineering and work practice controls if the following provisions are complied with.
Class IV asbestos jobs shall be conducted by employees trained pursuant to the asbestos awareness training program set out in paragraph (k)(9) of this section. In addition, all Class IV jobs shall be conducted in conformity with the requirements set out in paragraph (g)(1) of this section, mandating wet methods, HEPA vacuums, and prompt clean up of debris containing ACM or PACM.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer shall provide or require the use of protective clothing, such as coveralls or similar whole-body clothing, head coverings, gloves, and foot coverings for any employee exposed to airborne concentrations of asbestos that exceed the TWA and/or excursion limit prescribed in paragraph (c) of this section, or for which a required negative exposure assessment is not produced, or for any employee performing Class I operations which involve the removal of over 25 linear or 10 square feet of TSI or surfacing ACM and PACM.
Contaminated clothing shall be transported in sealed impermeable bags, or other closed, impermeable containers, and be labeled in accordance with paragraph (k) of this section.
The employer shall establish a decontamination area that is adjacent and connected to the regulated area for the decontamination of such employees. The decontamination area shall consist of an equipment room, shower area, and clean room in series. The employer shall ensure that employees enter and exit the regulated area through the decontamination area.
The equipment room shall be supplied with impermeable, labeled bags and containers for the containment and disposal of contaminated protective equipment.
Shower facilities shall be provided which comply with 29 CFR 1910.141(d)(3), unless the employer can demonstrate that they are not feasible. The showers shall be adjacent both to the equipment room and the clean room, unless the employer can demonstrate that this location is not feasible. Where the employer can demonstrate that it is not feasible to locate the shower between the equipment room and the clean room, or where the work is performed outdoors, the employers shall ensure that employees:
The clean room shall be equipped with a locker or appropriate storage container for each employee's use. When the employer can demonstrate that it is not feasible to provide a clean change area adjacent to the work area or where the work is performed outdoors, the employer may permit employees engaged in Class I asbestos jobs to clean their protective clothing with a portable HEPA-equipped vacuum before such employees leave the regulated area. Following showering, such employees however must then change into street clothing in clean change areas provided by the employer which otherwise meet the requirements of this section.
The employer shall ensure that employees:
The employer shall ensure that:
Whenever food or beverages are consumed at the worksite where employees are performing Class I asbestos work, the employer shall provide lunch areas in which the airborne concentrations of asbestos are below the permissible exposure limit and/or excursion limit.
Employers shall ensure that employees performing Class IV work within a regulated area comply with the hygiene practice required of employees performing work which has a higher classification within that regulated area. Otherwise employers of employees cleaning up debris and material which is TSI or surfacing ACM or identified as PACM shall provide decontamination facilities for such employees which are required by paragraph (j)(2) of this section.
The employer shall ensure that employees do not smoke in work areas where they are occupationally exposed to asbestos because of activities in that work area.
DANGER
ASBESTOS
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
AUTHORIZED PERSONNEL ONLY
WEAR RESPIRATORY PROTECTION AND PROTECTIVE CLOTHING IN THIS AREA
DANGER
ASBESTOS
CANCER AND LUNG DISEASE HAZARD
AUTHORIZED PERSONNEL ONLY
RESPIRATORS AND PROTECTIVE CLOTHING ARE REQUIRED IN THIS AREA
DANGER
CONTAINS ASBESTOS FIBERS
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
DO NOT BREATHE DUST
AVOID CREATING DUST
DANGER
CONTAINS ASBESTOS FIBERS
AVOID CREATING DUST
CANCER AND LUNG DISEASE HAZARD
Where vacuuming methods are selected, HEPA filtered vacuuming equipment must be used. The equipment shall be used and emptied in a manner that minimizes the reentry of asbestos into the workplace.
Asbestos waste, scrap, debris, bags, containers, equipment, and contaminated clothing consigned for disposal shall be collected and disposed of in sealed, labeled, impermeable bags or other closed, labeled, impermeable containers except in roofing operations, where the procedures specified in paragraph (g)(8)(ii) of this section apply.
The employer shall make available medical examinations and consultations to each employee covered under paragraph (m)(1)(i) of this section on the following schedules:
No medical examination is required of any employee if adequate records show that the employee has been examined in accordance with this paragraph within the past 1-year period.
Medical examinations made available pursuant to paragraphs (m)(2)(i)(A) through (m)(2)(i)(C) of this section shall include:
The employer shall provide the following information to the examining physician:
The employer shall maintain all employee training records for one (1) year beyond the last date of employment by that employer.
Where the building owner and employer have relied on data to demonstrate that PACM is not asbestos-containing, such data shall be maintained for as long as they are relied upon to rebut the presumption.
Where the building owner has communicated and received information concerning the identification, location and quantity of ACM and PACM, written records of such notifications and their content shall be maintained by the building owner for the duration of ownership and shall be transferred to successive owners of such buildings/facilities.
The employer must comply with the requirements concerning transfer of records set forth in 29 CFR 1910.1020(h).
On all construction worksites covered by this standard, the employer shall designate a competent person, having the qualifications and authorities for ensuring worker safety and health required by subpart C, General Safety and Health Provisions for Construction (29 CFR 1926.20 through 1926.32).
Section 1926.20(b)(2) which requires health and safety prevention programs to provide for frequent and regular inspections of the job sites, materials, and equipment to be made by competent persons, is incorporated.
In addition, the competent person shall make frequent and regular inspections of the job sites, in order to perform the duties set out below in paragraph (o)(3)(i) of this section. For Class I jobs, on-site inspections shall be made at least once during each work shift, and at any time at employee request. For Class II, III, and IV jobs, on-site inspections shall be made at intervals sufficient to assess whether conditions have changed, and at any reasonable time at employee request.
Appendix A to § 1926.1101—OSHA Reference Method—Mandatory
This mandatory appendix specifies the procedure for analyzing air samples for asbestos and specifies quality control procedures that must be implemented by laboratories performing the analysis. The sampling and analytical methods described below represent the elements of the available monitoring methods (such as appendix B of this regulation, the most current version of the OSHA method ID-160, or the most current version of the NIOSH Method 7400). All employers who are required to conduct air monitoring under paragraph (f) of the standard are required to utilize analytical laboratories that use this procedure, or an equivalent method, for collecting and analyzing samples.
Sampling and Analytical Procedure
1. The sampling medium for air samples shall be mixed cellulose ester filter membranes. These shall be designated by the manufacturer as suitable for asbestos counting. See below for rejection of blanks.
2. The preferred collection device shall be the 25-mm diameter cassette with an open-faced 50-mm electrically conductive extension cowl. The 37-mm cassette may be used if necessary but only if written justification for the need to use the 37-mm filter cassette accompanies the sample results in the employee's exposure monitoring record. Do not reuse or reload cassettes for asbestos sample collection.
3. An air flow rate between 0.5 liter/min and 2.5 liters/min shall be selected for the 25/mm cassette. If the 37-mm cassette is used, an air flow rate between 1 liter/min and 2.5 liters/min shall be selected.
4. Where possible, a sufficient air volume for each air sample shall be collected to yield between 100 and 1,300 fibers per square millimeter on the membrane filter. If a filter darkens in appearance or if loose dust is seen on the filter, a second sample shall be started.
5. Ship the samples in a rigid container with sufficient packing material to prevent dislodging the collected fibers. Packing material that has a high electrostatic charge on its surface (e.g., expanded polystyrene) cannot be used because such material can cause loss of fibers to the sides of the cassette.
6. Calibrate each personal sampling pump before and after use with a representative filter cassette installed between the pump and the calibration devices.
7. Personal samples shall be taken in the “breathing zone” of the employee (i.e., attached to or near the collar or lapel near the worker's face).
8. Fiber counts shall be made by positive phase contrast using a microscope with an 8 to 10× eyepiece and a 40 to 45× objective for a total magnification of approximately 400× and a numerical aperture of 0.65 to 0.75. The microscope shall also be fitted with a green or blue filter.
9. The microscope shall be fitted with a Walton-Beckett eyepiece graticule calibrated for a field diameter of 100 micrometers (±2 micrometers).
10. The phase-shift detection limit of the microscope shall be about 3 degrees measured using the HSE phase shift test slide as outlined below.
a. Place the test slide on the microscope stage and center it under the phase objective.
b. Bring the blocks of grooved lines into focus.
c. If the image deteriorates, clean and adjust the microscope optics. If the problem persists, cosult the microscope manufacturer.
11. Each set of samples taken will include 10% field blanks or a minimum of 2 field blanks. These blanks must come from the same lot as the filters used for sample collection. The field blank results shall be averaged and subtracted from the analytical results before reporting. A set consists of any sample or group of samples for which an evaluation for this standard must be made. Any samples represented by a field blank having a fiber count in excess of the detection limit of the method being used shall be rejected.
12. The samples shall be mounted by the acetone/triacetin method or a method with an equivalent index of refraction and similar clarity.
13. Observe the following counting rules.
a. Count only fibers equal to or longer than 5 micrometers. Measure the length of curved fibers along the curve.
b. In the absence of other information, count all particles as asbestos, that have a length-to-width ratio (aspect ratio) of 3:1 or greater.
c. Fibers lying entirely within the boundary of the Walton-Beckett graticule field shall receive a count of 1. Fibers crossing the boundary once, having one end within the circle, shall receive the count of one half ( 1/2 ). Do not count any fiber that crosses the graticule boundary more than once. Reject and do not count any other fibers even though they may be visible outside the graticule area.
d. Count bundles of fibers as one fiber unless individual fibers can be identified by observing both ends of an individual fiber.
e. Count enough graticule fields to yield 100 fibers. Count a minimum of 20 fields; stop counting at 100 fields regardless of fiber count.
14. Blind recounts shall be conducted at the rate of 10 percent.
Quality Control Procedures
1. Intralaboratory program. Each laboratory and/or each company with more than one microscopist counting slides shall establish a statistically designed quality assurance program involving blind recounts and comparisons between microscopists to monitor the variability of counting by each microscopist and between microscopists. In a company with more than one laboratory, the program shall include all laboratories, and shall also evaluate the laboratory-to-laboratory variability.
2a. Interlaboratory program. Each laboratory analyzing asbestos samples for compliance determination shall implement an interlaboratory quality assurance program that, as a minimum, includes participation of at least two other independent laboratories. Each laboratory shall participate in round robin testing at least once every 6 months with at least all the other laboratories in its interlaboratory quality assurance group. Each laboratory shall submit slides typical of its own workload for use in this program. The round robin shall be designed and results analyzed using appropriate statistical methodology.
b. All laboratories should also participate in a national sample testing scheme such as the Proficiency Analytical Testing Program (PAT), or the Asbestos Registry sponsored by the American Industrial Hygiene Association (AIHA).
3. All individuals performing asbestos analysis must have taken the NIOSH course for sampling and evaluating airborne asbestos dust or an equivalent course.
4. When the use of different microscopes contributes to differences between counters and laboratories, the effect of the different microscope shall be evaluated and the microscope shall be replaced, as necessary.
5. Current results of these quality assurance programs shall be posted in each laboratory to keep the microscopists informed.
Appendix B to § 1926.1101—Sampling and Analysis (Non-Mandatory)
| Matrix Air: | |
|---|---|
| OSHA Permissible Exposure Limits: | |
| Time Weighted Average | 0.1 fiber/cc |
| Excursion Level (30 minutes) | 1.0 fiber/cc |
| Collection Procedure: | |
| A known volume of air is drawn through a 25-mm diameter cassette containing a mixed-cellulose ester filter. The cassette must be equipped with an electrically conductive 50-mm extension cowl. The sampling time and rate are chosen to give a fiber density of between 100 to 1,300 fibers/mm2 on the filter. |
| Recommended Sampling Rate | 0.5 to 5.0 liters/minute (L/min) |
|---|---|
| Recommended Air Volumes: | |
| Minimum | 25 L |
| Maximum | 2,400 L |
Analytical Procedure:
A portion of the sample filter is cleared and prepared for asbestos fiber counting by Phase Contrast Microscopy (PCM) at 400X.
Commercial manufacturers and products mentioned in this method are for descriptive use only and do not constitute endorsements by USDOL-OSHA. Similar products from other sources can be substituted.
1. Introduction
This method describes the collection of airborne asbestos fibers using calibrated sampling pumps with mixed-cellulose ester (MCE) filters and analysis by phase contrast microscopy (PCM). Some terms used are unique to this method and are defined below: Asbestos: A term for naturally occurring fibrous minerals. Asbestos includes chrysotile, crocidolite, amosite (cummingtonite-grunerite asbestos), tremolite asbestos, actinolite asbestos, anthophyllite asbestos, and any of these minerals that have been chemically treated and/or altered. The precise chemical formulation of each species will vary with the location from which it was mined. Nominal compositions are listed:
| Chrysotile | Mg 3 Si 2 O 5 (OH) 4 |
|---|---|
| Crocidolite | Na 2 Fe 3 2 + Fe 2 3 + Si 8 O 22 (OH) 2 |
| Amosite | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
| Tremolite-actinolite | Ca 2 (Mg,Fe) 5 Si 8 O 22 (OH) 2 |
| Anthophyllite | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
Asbestos Fiber: A fiber of asbestos which meets the criteria specified below for a fiber.
Aspect Ratio: The ratio of the length of a fiber to it's diameter (e.g. 3:1, 5:1 aspect ratios).
Cleavage Fragments: Mineral particles formed by comminution of minerals, especially those characterized by parallel sides and a moderate aspect ratio (usually less than 20:1).
Detection Limit: The number of fibers necessary to be 95% certain that the result is greater than zero.
Differential Counting: The term applied to the practice of excluding certain kinds of fibers from the fiber count because they do not appear to be asbestos.
Fiber: A particle that is 5 µm or longer, with a length-to-width ratio of 3 to 1 or longer.
Field: The area within the graticule circle that is superimposed on the microscope image.
Set: The samples which are taken, submitted to the laboratory, analyzed, and for which, interim or final result reports are generated.
Tremolite, Anthophyllite, and Actinolite: The non-asbestos form of these minerals which meet the definition of a fiber. It includes any of these minerals that have been chemically treated and/or altered.
Walton-Beckett Graticule: An eyepiece graticule specifically designed for asbestos fiber counting. It consists of a circle with a projected diameter of 100 ±2 µm (area of about 0.00785 mm 2 ) with a crosshair having tic-marks at 3-µm intervals in one direction and 5-µm in the orthogonal direction. There are marks around the periphery of the circle to demonstrate the proper sizes and shapes of fibers. This design is reproduced in Figure 1. The disk is placed in one of the microscope eyepieces so that the design is superimposed on the field of view.
1.1. History
Early surveys to determine asbestos exposures were conducted using impinger counts of total dust with the counts expressed as million particles per cubic foot. The British Asbestos Research Council recommended filter membrane counting in 1969. In July 1969, the Bureau of Occupational Safety and Health published a filter membrane method for counting asbestos fibers in the United States. This method was refined by NIOSH and published as P & CAM 239. On May 29, 1971, OSHA specified filter membrane sampling with phase contrast counting for evaluation of asbestos exposures at work sites in the United States. The use of this technique was again required by OSHA in 1986. Phase contrast microscopy has continued to be the method of choice for the measurement of occupational exposure to asbestos.
1.2. Principle
Air is drawn through a MCE filter to capture airborne asbestos fibers. A wedge shaped portion of the filter is removed, placed on a glass microscope slide and made transparent. A measured area (field) is viewed by PCM. All the fibers meeting defined criteria for asbestos are counted and considered a measure of the airborne asbestos concentration.
1.3. Advantages and Disadvantages
There are four main advantages of PCM over other methods:
Phase contrast is a fiber counting technique which excludes non-fibrous particles from the analysis.
The main disadvantage of PCM is that it does not positively identify asbestos fibers. Other fibers which are not asbestos may be included in the count unless differential counting is performed. This requires a great deal of experience to adequately differentiate asbestos from non-asbestos fibers. Positive identification of asbestos must be performed by polarized light or electron microscopy techniques. A further disadvantage of PCM is that the smallest visible fibers are about 0.2 µm in diameter while the finest asbestos fibers may be as small as 0.02 µm in diameter. For some exposures, substantially more fibers may be present than are actually counted.
1.4. Workplace Exposure
Asbestos is used by the construction industry in such products as shingles, floor tiles, asbestos cement, roofing felts, insulation and acoustical products. Non-construction uses include brakes, clutch facings, paper, paints, plastics, and fabrics. One of the most significant exposures in the workplace is the removal and encapsulation of asbestos in schools, public buildings, and homes. Many workers have the potential to be exposed to asbestos during these operations.
About 95% of the asbestos in commercial use in the United States is chrysotile. Crocidolite and amosite make up most of the remainder. Anthophyllite and tremolite or actinolite are likely to be encountered as contaminants in various industrial products.
1.5. Physical Properties
Asbestos fiber possesses a high tensile strength along its axis, is chemically inert, non-combustible, and heat resistant. It has a high electrical resistance and good sound absorbing properties. It can be weaved into cables, fabrics or other textiles, and also matted into asbestos papers, felts, or mats.
2. Range and Detection Limit
2.1. The ideal counting range on the filter is 100 to 1,300 fibers/mm 2. With a Walton-Beckett graticule this range is equivalent to 0.8 to 10 fibers/field. Using NIOSH counting statistics, a count of 0.8 fibers/field would give an approximate coefficient of variation (CV) of 0.13.
2.2. The detection limit for this method is 4.0 fibers per 100 fields or 5.5 fibers/mm 2. This was determined using an equation to estimate the maximum CV possible at a specific concentration (95% confidence) and a Lower Control Limit of zero. The CV value was then used to determine a corresponding concentration from historical CV vs fiber relationships. As an example:
Lower Control Limit (95% Confidence) = AC—1.645(CV)(AC)
Where:
AC = Estimate of the airborne fiber concentration (fibers/cc) Setting the Lower Control Limit = 0 and solving for CV:
0 = AC—1.645(CV)(AC)
CV = 0.61
This value was compared with CV vs. count curves. The count at which CV = 0.61 for Leidel-Busch counting statistics or for an OSHA Salt Lake Technical Center (OSHA-SLTC) CV curve (see appendix A for further information) was 4.4 fibers or 3.9 fibers per 100 fields, respectively. Although a lower detection limit of 4 fibers per 100 fields is supported by the OSHA-SLTC data, both data sets support the 4.5 fibers per 100 fields value.
3. Method Performance—Precision and Accuracy
Precision is dependent upon the total number of fibers counted and the uniformity of the fiber distribution on the filter. A general rule is to count at least 20 and not more than 100 fields. The count is discontinued when 100 fibers are counted, provided that 20 fields have already been counted. Counting more than 100 fibers results in only a small gain in precision. As the total count drops below 10 fibers, an accelerated loss of precision is noted.
At this time, there is no known method to determine the absolute accuracy of the asbestos analysis. Results of samples prepared through the Proficiency Analytical Testing (PAT) Program and analyzed by the OSHA-SLTC showed no significant bias when compared to PAT reference values. The PAT samples were analyzed from 1987 to 1989 (N = 36) and the concentration range was from 120 to 1,300 fibers/mm 2.
4. Interferences
Fibrous substances, if present, may interfere with asbestos analysis.
Some common fibers are:
fiberglass
anhydrite
plant fibers
perlite veins
gypsum
some synthetic fibers
membrane structures
sponge spicules
diatoms
microorganisms
wollastonite
The use of electron microscopy or optical tests such as polarized light, and dispersion staining may be used to differentiate these materials from asbestos when necessary.
5. Sampling
5.1. Equipment
5.1.1. Sample assembly (The assembly is shown in Figure 3). Conductive filter holder consisting of a 25-mm diameter, 3-piece cassette having a 50-mm long electrically conductive extension cowl. Backup pad, 25-mm, cellulose. Membrane filter, mixed-cellulose ester (MCE), 25-mm, plain, white, 0.4 to 1.2-µm pore size.
5.1.2. Gel bands for sealing cassettes.
5.1.3. Sampling pump.
Each pump must be a battery operated, self-contained unit small enough to be placed on the monitored employee and not interfere with the work being performed. The pump must be capable of sampling at the collection rate for the required sampling time.
5.1.4. Flexible tubing, 6-mm bore.
5.1.5. Pump calibration.
Stopwatch and bubble tube/burette or electronic meter.
5.2. Sampling Procedure
5.2.1. Seal the point where the base and cowl of each cassette meet with a gel band or tape.
5.2.2. Charge the pumps completely before beginning.
5.2.3. Connect each pump to a calibration cassette with an appropriate length of 6-mm bore plastic tubing. Do not use luer connectors—the type of cassette specified above has built-in adapters.
5.2.4. Select an appropriate flow rate for the situation being monitored. The sampling flow rate must be between 0.5 and 5.0 L/min for personal sampling and is commonly set between 1 and 2 L/min. Always choose a flow rate that will not produce overloaded filters.
5.2.5. Calibrate each sampling pump before and after sampling with a calibration cassette in-line (Note: This calibration cassette should be from the same lot of cassettes used for sampling). Use a primary standard (e.g. bubble burette) to calibrate each pump. If possible, calibrate at the sampling site.
5.2.6. Connect each pump to the base of each sampling cassette with flexible tubing. Remove the end cap of each cassette and take each air sample open face. Assure that each sample cassette is held open side down in the employee's breathing zone during sampling. The distance from the nose/mouth of the employee to the cassette should be about 10 cm. Secure the cassette on the collar or lapel of the employee using spring clips or other similar devices.
5.2.7. A suggested minimum air volume when sampling to determine TWA compliance is 25 L. For Excursion Limit (30 min sampling time) evaluations, a minimum air volume of 48 L is recommended.
5.2.8. The most significant problem when sampling for asbestos is overloading the filter with non-asbestos dust. Suggested maximum air sample volumes for specific environments are:
| Environment | Air Vol. (L) |
|---|---|
| Asbestos removal operations (visible dust) | 100. |
| Asbestos removal operations (little dust) | 240. |
| Office environments | 400 to 2,400. |
CAUTION: Do not overload the filter with dust. High levels of non-fibrous dust particles may obscure fibers on the filter and lower the count or make counting impossible. If more than about 25 to 30% of the field area is obscured with dust, the result may be biased low. Smaller air volumes may be necessary when there is excessive non-asbestos dust in the air.
While sampling, observe the filter with a small flashlight. If there is a visible layer of dust on the filter, stop sampling, remove and seal the cassette, and replace with a new sampling assembly. The total dust loading should not exceed 1 mg.
5.2.9. Blank samples are used to determine if any contamination has occurred during sample handling. Prepare two blanks for the first 1 to 20 samples. For sets containing greater than 20 samples, prepare blanks as 10% of the samples. Handle blank samples in the same manner as air samples with one exception: Do not draw any air through the blank samples. Open the blank cassette in the place where the sample cassettes are mounted on the employee. Hold it open for about 30 seconds. Close and seal the cassette appropriately. Store blanks for shipment with the sample cassettes.
5.2.10. Immediately after sampling, close and seal each cassette with the base and plastic plugs. Do not touch or puncture the filter membrane as this will invalidate the analysis.
5.2.11 Attach and secure a sample seal around each sample cassette in such a way as to assure that the end cap and base plugs cannot be removed without destroying the seal. Tape the ends of the seal together since the seal is not long enough to be wrapped end-to-end. Also wrap tape around the cassette at each joint to keep the seal secure.
5.3.1. Send the samples to the laboratory with paperwork requesting asbestos analysis. List any known fibrous interferences present during sampling on the paperwork. Also, note the workplace operation(s) sampled.
5.3.2. Secure and handle the samples in such that they will not rattle during shipment nor be exposed to static electricity. Do not ship samples in expanded polystyrene peanuts, vermiculite, paper shreds, or excelsior. Tape sample cassettes to sheet bubbles and place in a container that will cushion the samples in such a manner that they will not rattle.
5.3.3. To avoid the possibility of sample contamination, always ship bulk samples in separate mailing containers.
6. Analysis
6.1. Safety Precautions
6.1.1. Acetone is extremely flammable and precautions must be taken not to ignite it. Avoid using large containers or quantities of acetone. Transfer the solvent in a ventilated laboratory hood. Do not use acetone near any open flame. For generation of acetone vapor, use a spark free heat source.
6.1.2. Any asbestos spills should be cleaned up immediately to prevent dispersal of fibers. Prudence should be exercised to avoid contamination of laboratory facilities or exposure of personnel to asbestos. Asbestos spills should be cleaned up with wet methods and/or a High Efficiency Particulate-Air (HEPA) filtered vacuum.
CAUTION: Do not use a vacuum without a HEPA filter—It will disperse fine asbestos fibers in the air.
6.2. Equipment
6.2.1. Phase contrast microscope with binocular or trinocular head.
6.2.2. Widefield or Huygenian 10X eyepieces (NOTE: The eyepiece containing the graticule must be a focusing eyepiece. Use a 40X phase objective with a numerical aperture of 0.65 to 0.75).
6.2.3. Kohler illumination (if possible) with green or blue filter.
6.2.4. Walton-Beckett Graticule, type G-22 with 100 ±2 µm projected diameter.
6.2.5. Mechanical stage. A rotating mechanical stage is convenient for use with polarized light.
6.2.6. Phase telescope.
6.2.7. Stage micrometer with 0.01-mm subdivisions.
6.2.8. Phase-shift test slide, mark II (Available from PTR optics Ltd., and also McCrone).
6.2.9. Precleaned glass slides, 25 mm × 75 mm. One end can be frosted for convenience in writing sample numbers, etc., or paste-on labels can be used.
6.2.10. Cover glass #1 1/2.
6.2.11. Scalpel (#10, curved blade).
6.2.12. Fine tipped forceps.
6.2.13. Aluminum block for clearing filter (see appendix D and Figure 4).
6.2.14. Automatic adjustable pipette, 100- to 500-µL.
6.2.15. Micropipette, 5 µL.
6.3. Reagents
6.3.1. Acetone (HPLC grade).
6.3.2. Triacetin (glycerol triacetate).
6.3.3. Lacquer or nail polish.
6.4. Standard Preparation
A way to prepare standard asbestos samples of known concentration has not been developed. It is possible to prepare replicate samples of nearly equal concentration. This has been performed through the PAT program. These asbestos samples are distributed by the AIHA to participating laboratories.
Since only about one-fourth of a 25-mm sample membrane is required for an asbestos count, any PAT sample can serve as a “standard” for replicate counting.
6.5. Sample Mounting
An aluminum block or similar device is required for sample preparation.
6.5.1. Heat the aluminum block to about 70 °C. The hot block should not be used on any surface that can be damaged by either the heat or from exposure to acetone.
6.5.2. Ensure that the glass slides and cover glasses are free of dust and fibers.
6.5.3. Remove the top plug to prevent a vacuum when the cassette is opened. Clean the outside of the cassette if necessary. Cut the seal and/or tape on the cassette with a razor blade. Very carefully separate the base from the extension cowl, leaving the filter and backup pad in the base.
6.5.4. With a rocking motion cut a triangular wedge from the filter using the scalpel. This wedge should be one-sixth to one-fourth of the filter. Grasp the filter wedge with the forceps on the perimeter of the filter which was clamped between the cassette pieces. DO NOT TOUCH the filter with your finger. Place the filter on the glass slide sample side up. Static electricity will usually keep the filter on the slide until it is cleared.
6.5.5. Place the tip of the micropipette containing about 200 µL acetone into the aluminum block. Insert the glass slide into the receiving slot in the aluminum block. Inject the acetone into the block with slow, steady pressure on the plunger while holding the pipette firmly in place. Wait 3 to 5 seconds for the filter to clear, then remove the pipette and slide from the aluminum block.
6.5.6. Immediately (less than 30 seconds) place 2.5 to 3.5 µL of triacetin on the filter (NOTE: Waiting longer than 30 seconds will result in increased index of refraction and decreased contrast between the fibers and the preparation. This may also lead to separation of the cover slip from the slide).
6.5.7. Lower a cover slip gently onto the filter at a slight angle to reduce the possibility of forming air bubbles. If more than 30 seconds have elapsed between acetone exposure and triacetin application, glue the edges of the cover slip to the slide with lacquer or nail polish.
6.5.8. If clearing is slow, warm the slide for 15 min on a hot plate having a surface temperature of about 50 °C to hasten clearing. The top of the hot block can be used if the slide is not heated too long.
6.5.9. Counting may proceed immediately after clearing and mounting are completed.
6.6. Sample Analysis
Completely align the microscope according to the manufacturer's instructions. Then, align the microscope using the following general alignment routine at the beginning of every counting session and more often if necessary.
6.6.1. Alignment
Even a small amount of dirt can significantly degrade the image.
6.6.2. Counting Fibers
6.7. Fiber Identification
As previously mentioned in Section 1.3., PCM does not provide positive confirmation of asbestos fibers. Alternate differential counting techniques should be used if discrimination is desirable. Differential counting may include primary discrimination based on morphology, polarized light analysis of fibers, or modification of PCM data by Scanning Electron or Transmission Electron Microscopy.
A great deal of experience is required to routinely and correctly perform differential counting. It is discouraged unless it is legally necessary. Then, only if a fiber is obviously not asbestos should it be excluded from the count. Further discussion of this technique can be found in reference 8.10.
If there is a question whether a fiber is asbestos or not, follow the rule:
“WHEN IN DOUBT, COUNT.”
6.8. Analytical Recommendations—Quality Control System
6.8.1. All individuals performing asbestos analysis must have taken the NIOSH course for sampling and evaluating airborne asbestos or an equivalent course.
6.8.2. Each laboratory engaged in asbestos counting shall set up a slide trading arrangement with at least two other laboratories in order to compare performance and eliminate inbreeding of error. The slide exchange occurs at least semiannually. The round robin results shall be posted where all analysts can view individual analyst's results.
6.8.3. Each laboratory engaged in asbestos counting shall participate in the Proficiency Analytical Testing Program, the Asbestos Analyst Registry or equivalent.
6.8.4. Each analyst shall select and count prepared slides from a “slide bank”. These are quality assurance counts. The slide bank shall be prepared using uniformly distributed samples taken from the workload. Fiber densities should cover the entire range routinely analyzed by the laboratory. These slides are counted blind by all counters to establish an original standard deviation. This historical distribution is compared with the quality assurance counts. A counter must have 95% of all quality control samples counted within three standard deviations of the historical mean. This count is then integrated into a new historical mean and standard deviation for the slide.
The analyses done by the counters to establish the slide bank may be used for an interim quality control program if the data are treated in a proper statistical fashion.
7. Calculations
7.1. Calculate the estimated airborne asbestos fiber concentration on the filter sample using the following formula:
AC = Airborne fiber concentration
FB = Total number of fibers greater than 5 µm counted
FL = Total number of fields counted on the filter
BFB = Total number of fibers greater than 5 µm counted in the blank
BFL = Total number of fields counted on the blank
2
FR = Pump flow rate (L/min)
2
2
T = Sample collection time (min)
1,000 = Conversion of L to cc
7.2. Short-Cut Calculation
Since a given analyst always has the same interpupillary distance, the number of fields per filter for a particular analyst will remain constant for a given size filter. The field size for that analyst is constant (i.e. the analyst is using an assigned microscope and is not changing the reticle).
For example, if the exposed area of the filter is always 385 mm 2 and the size of the field is always 0.00785 mm 2 the number of fields per filter will always be 49,000. In addition it is necessary to convert liters of air to cc. These three constants can then be combined such that ECA/(1,000 × MFA) = 49. The previous equation simplifies to:
As mentioned in step 13 of Section 6.6.2., a “blind recount” of 10% of the slides is performed. In all cases, differences will be observed between the first and second counts of the same filter wedge. Most of these differences will be due to chance alone, that is, due to the random variability (precision) of the count method. Statistical recount criteria enables one to decide whether observed differences can be explained due to chance alone or are probably due to systematic differences between analysts, microscopes, or other biasing factors.
The following recount criterion is for a pair of counts that estimate AC in fibers/cc. The criterion is given at the type-I error level. That is, there is 5% maximum risk that we will reject a pair of counts for the reason that one might be biased, when the large observed difference is really due to chance.
Reject a pair of counts if:
1
2
avg
FB
If a pair of counts are rejected by this criterion then, recount the rest of the filters in the submitted set. Apply the test and reject any other pairs failing the test. Rejection shall include a memo to the industrial hygienist stating that the sample failed a statistical test for homogeneity and the true air concentration may be significantly different than the reported value.
7.4. Reporting Results
Report results to the industrial hygienist as fibers/cc. Use two significant figures. If multiple analyses are performed on a sample, an average of the results is to be reported unless any of the results can be rejected for cause.
8. References
8.1. Dreesen, W.C., et al., U.S. Public Health Service: A Study of Asbestosis in the Asbestos Textile Industry (Public Health Bulletin No. 241), U.S. Treasury Dept., Washington, DC, 1938.
8.2. Asbestos Research Council: The Measurement of Airborne Asbestos Dust by the Membrane Filter Method (Technical Note), Asbestos Research Council, Rockdale, Lancashire, Great Britain, 1969.
8.3. Bayer, S.G., Zumwalde, R.D., Brown, T.A., Equipment and Procedure for Mounting Millipore Filters and Counting Asbestos Fibers by Phase Contrast Microscopy, Bureau of Occupational Health, U.S. Dept. of Health, Education and Welfare, Cincinnati, OH, 1969.
8.4. NIOSH Manual of Analytical Methods, 2nd ed., Vol. 1 (DHEW/NIOSH Pub. No. 77-157-A). National Institute for Occupational Safety and Health, Cincinnati, OH, 1977. pp. 239-1—239-21.
8.5. Asbestos, Code of Federal Regulations 29 CFR 1910.1001. 1971.
8.6. Occupational Exposure to Asbestos, Tremolite, Anthophyllite, and Actinolite. Final Rule, Federal Register 51:119 (20 June 1986). pp. 22612-22790.
8.7. Asbestos, Tremolite, Anthophyllite, and Actinolite, Code of Federal Regulations 1910.1001. 1988. pp. 711-752.
8.8. Criteria for a Recommended Standard—Occupational Exposure to Asbestos (DHEW/NIOSH Pub. No. HSM 72-10267), National Institute for Occupational Safety and Health, NIOSH, Cincinnati, OH, 1972. pp. III-1—III-24.
8.9. Leidel, N.A., Bayer, S.G., Zumwalde, R.D., Busch, K.A., USPHS/NIOSH Membrane Filter Method for Evaluating Airborne Asbestos Fibers (DHEW/NIOSH Pub. No. 79-127). National Institute for Occupational Safety and Health, Cincinnati, OH, 1979.
8.10. Dixon, W.C., Applications of Optical Microscopy in Analysis of Asbestos and Quartz, Analytical Techniques in Occupational Health Chemistry, edited by D.D. Dollberg and A.W. Verstuyft. Wash. DC: American Chemical Society, (ACS Symposium Series 120) 1980. pp. 13-41.
Quality Control
The OSHA asbestos regulations require each laboratory to establish a quality control program. The following is presented as an example of how the OSHA-SLTC constructed its internal CV curve as part of meeting this requirement. Data is from 395 samples collected during OSHA compliance inspections and analyzed from October 1980 through April 1986.
Each sample was counted by 2 to 5 different counters independently of one another. The standard deviation and the CV statistic was calculated for each sample. This data was then plotted on a graph of CV vs. fibers/mm 2. A least squares regression was performed using the following equation:
10
10
2
10
where:
2
Application of least squares gave:
A = 0.182205
B = 0.973343
C = 0.327499
Using these values, the equation becomes:
10
10
2
10
Sampling Pump Flow Rate Corrections
This correction is used if a difference greater than 5% in ambient temperature and/or pressure is noted between calibration and sampling sites and the pump does not compensate for the differences.
act
cal
cal
act
act
cal
Walton-Beckett Graticule
When ordering the Graticule for asbestos counting, specify the exact disc diameter needed to fit the ocular of the microscope and the diameter (mm) of the circular counting area. Instructions for measuring the dimensions necessary are listed:
Calculate the circle diameter, d c (mm), for the Walton-Beckett graticule and specify the diameter when making a purchase:
Measure the field diameter, D (acceptable range: 100 ±2 µm) with a stage micrometer upon receipt of the graticule from the manufacturer. Determine the field area (mm 2 ).
†
2
If D = 100 µm = 0.1 mm, then
†
2
2
The Graticule is available from: Graticules Ltd., Morley Road, Tonbridge TN9 IRN, Kent, England (Telephone 011-44-732-359061). Also available from PTR Optics Ltd., 145 Newton Street, Waltham, MA 02154 [telephone (617) 891-6000] or McCrone Accessories and Components, 2506 S. Michigan Ave., Chicago, IL 60616 [phone (312)-842-7100]. The graticule is custom made for each microscope.
| Structure No. | Count | Explanation |
|---|---|---|
| 1 to 6 | 1 | Single fibers all contained within the Circle. |
| 7 | 1 ⁄ 2 | Fiber crosses circle once. |
| 8 | 0 | Fiber too short. |
| 9 | 2 | Two crossing fibers. |
| 10 | 0 | Fiber outside graticule. |
| 11 | 0 | Fiber crosses graticule twice. |
| 12 | 1 ⁄ 2 | Although split, fiber only crosses once. |
Appendix E to § 1926.1101—Classification of Chest X-Rays—Mandatory
Appendix F to § 1926.1101—Work Practices and Engineering Controls for Class I Asbestos Operations (Non-Mandatory)
This is a non-mandatory appendix to the asbestos standards for construction and for shipyards. It describes criteria and procedures for erecting and using negative pressure enclosures for Class I Asbestos Work, when NPEs are used as an allowable control method to comply with paragraph (g)(5)(i) of this section. Many small and variable details are involved in the erection of a negative pressure enclosure. OSHA and most participants in the rulemaking agreed that only the major, more performance oriented criteria should be made mandatory. These criteria are set out in paragraph (g) of this section. In addition, this appendix includes these mandatory specifications and procedures in its guidelines in order to make this appendix coherent and helpful. The mandatory nature of the criteria which appear in the regulatory text is not changed because they are included in this “non-mandatory” appendix. Similarly, the additional criteria and procedures included as guidelines in the appendix, do not become mandatory because mandatory criteria are also included in these comprehensive guidelines.
In addition, none of the criteria, both mandatory and recommended, are meant to specify or imply the need for use of patented or licensed methods or equipment. Recommended specifications included in this attachment should not discourage the use of creative alternatives which can be shown to reliably achieve the objectives of negative-pressure enclosures.
Requirements included in this appendix, cover general provisions to be followed in all asbestos jobs, provisions which must be followed for all Class I asbestos jobs, and provisions governing the construction and testing of negative pressure enclosures. The first category includes the requirement for use of wet methods, HEPA vacuums, and immediate bagging of waste; Class I work must conform to the following provisions:
• oversight by competent person
• use of critical barriers over all openings to work area
• isolation of HVAC systems
• use of impermeable dropcloths and coverage of all objects within regulated areas
In addition, more specific requirements for NPEs include:
• maintenance of −0.02 inches water gauge within enclosure
• manometric measurements
• air movement away from employees performing removal work
• smoke testing or equivalent for detection of leaks and air direction
• deactivation of electrical circuits, if not provided with ground-fault circuit interrupters.
Planning the Project
The standard requires that an exposure assessment be conducted before the asbestos job is begun [§ 1926.1101 (f)(1)]. Information needed for that assessment, includes data relating to prior similar jobs, as applied to the specific variables of the current job. The information needed to conduct the assessment will be useful in planning the project, and in complying with any reporting requirements under this standard, when significant changes are being made to a control system listed in the standard, [see also those of USEPA (40 CFR 61, subpart M). Thus, although the standard does not explicitly require the preparation of a written asbestos removal plan, the usual constituents of such a plan, i.e., a description of the enclosure, the equipment, and the procedures to be used throughout the project, must be determined before the enclosure can be erected. The following information should be included in the planning of the system:
A physical description of the work area;
A description of the approximate amount of material to be removed;
A schedule for turning off and sealing existing ventilation systems;
Personnel hygiene procedures;
A description of personal protective equipment and clothing to be worn by employees;
A description of the local exhaust ventilation systems to be used and how they are to be tested;
A description of work practices to be observed by employees;
An air monitoring plan;
A description of the method to be used to transport waste material; and
The location of the dump site.
Materials and Equipment Necessary for Asbestos Removal
Although individual asbestos removal projects vary in terms of the equipment required to accomplish the removal of the materials, some equipment and materials are common to most asbestos removal operations.
Plastic sheeting used to protect horizontal surfaces, seal HVAC openings or to seal vertical openings and ceilings should have a minimum thickness of 6 mils. Tape or other adhesive used to attach plastic sheeting should be of sufficient adhesive strength to support the weight of the material plus all stresses encountered during the entire duration of the project without becoming detached from the surface.
Other equipment and materials which should be available at the beginning of each project are:
—HEPA Filtered Vacuum is essential for cleaning the work area after the asbestos has been removed. It should have a long hose capable of reaching out-of-the-way places, such as areas above ceiling tiles, behind pipes, etc.
—Portable air ventilation systems installed to provide the negative air pressure and air removal from the enclosure must be equipped with a HEPA filter. The number and capacity of units required to ventilate an enclosure depend on the size of the area to be ventilated. The filters for these systems should be designed in such a manner that they can be replaced when the air flow volume is reduced by the build-up of dust in the filtration material. Pressure monitoring devices with alarms and strip chart recorders attached to each system to indicate the pressure differential and the loss due to dust buildup on the filter are recommended.
—Water sprayers should be used to keep the asbestos material as saturated as possible during removal; the sprayers will provide a fine mist that minimizes the impact of the spray on the material.
1/4
—Backup power supplies are recommended, especially for ventilation systems.
—Shower and bath water should be with mixed hot and cold water faucets. Water that has been used to clean personnel or equipment should either be filtered or be collected and discarded as asbestos waste. Soap and shampoo should be provided to aid in removing dust from the workers' skin and hair.
—See paragraphs (h) and (i) of this section for appropriate respiratory protection and protective clothing.
—See paragraph (k) of this section for required signs and labels.
Preparing the Work Area
Disabling HVAC Systems: The power to the heating, ventilation, and air conditioning systems that service the restricted area must be deactivated and locked off. All ducts, grills, access ports, windows and vents must be sealed off with two layers of plastic to prevent entrainment of contaminated air.
Operating HVAC Systems in the Restricted Area: If components of a HVAC system located in the restricted area are connected to a system that will service another zone during the project, the portion of the duct in the restricted area must be sealed and pressurized. Necessary precautions include caulking the duct joints, covering all cracks and openings with two layers of sheeting, and pressurizing the duct throughout the duration of the project by restricting the return air flow. The power to the fan supplying the positive pressure should be locked “on” to prevent pressure loss.
Sealing Elevators: If an elevator shaft is located in the restricted area, it should be either shut down or isolated by sealing with two layers of plastic sheeting. The sheeting should provide enough slack to accommodate the pressure changes in the shaft without breaking the air-tight seal.
Removing Mobile Objects: All movable objects should be cleaned and removed from the work area before an enclosure is constructed unless moving the objects creates a hazard. Mobile objects will be assumed to be contaminated and should be either cleaned with amended water and a HEPA vacuum and then removed from the area or wrapped and then disposed of as hazardous waste.
Cleaning and Sealing Surfaces: After cleaning with water and a HEPA vacuum, surfaces of stationary objects should be covered with two layers of plastic sheeting. The sheeting should be secured with duct tape or an equivalent method to provide a tight seal around the object.
Bagging Waste: In addition to the requirement for immediate bagging of waste for disposal, it is further recommended that the waste material be double-bagged and sealed in plastic bags designed for asbestos disposal. The bags should be stored in a waste storage area that can be controlled by the workers conducting the removal. Filters removed from air handling units and rubbish removed from the area are to be bagged and handled as hazardous waste.
Constructing the Enclosure
The enclosure should be constructed to provide an air-tight seal around ducts and openings into existing ventilation systems and around penetrations for electrical conduits, telephone wires, water lines, drain pipes, etc. Enclosures should be both airtight and watertight except for those openings designed to provide entry and/or air flow control.
Size: An enclosure should be the minimum volume to encompass all of the working surfaces yet allow unencumbered movement by the worker(s), provide unrestricted air flow past the worker(s), and ensure walking surfaces can be kept free of tripping hazards.
Shape: The enclosure may be any shape that optimizes the flow of ventilation air past the worker(s).
Structural Integrity: The walls, ceilings and floors must be supported in such a manner that portions of the enclosure will not fall down during normal use.
Openings: It is not necessary that the structure be airtight; openings may be designed to direct air flow. Such openings should be located at a distance from active removal operations. They should be designed to draw air into the enclosure under all anticipated circumstances. In the event that negative pressure is lost, they should be fitted with either HEPA filters to trap dust or automatic trap doors that prevent dust from escaping the enclosure. Openings for exits should be controlled by an airlock or a vestibule.
Barrier Supports: Frames should be constructed to support all unsupported spans of sheeting.
Sheeting: Walls, barriers, ceilings, and floors should be lined with two layers of plastic sheeting having a thickness of at least 6 mil.
Seams: Seams in the sheeting material should be minimized to reduce the possibilities of accidental rips and tears in the adhesive or connections. All seams in the sheeting should overlap, be staggered and not be located at corners or wall-to-floor joints. Areas Within an Enclosure: Each enclosure consists of a work area, a decontamination area, and waste storage area. The work area where the asbestos removal operations occur should be separated from both the waste storage area and the contamination control area by physical curtains, doors, and/or airflow patterns that force any airborne contamination back into the work area.
See paragraph (j) of this section for requirements for hygiene facilities.
During egress from the work area, each worker should step into the equipment room, clean tools and equipment, and remove gross contamination from clothing by wet cleaning and HEPA vacuuming. Before entering the shower area, foot coverings, head coverings, hand coverings, and coveralls are removed and placed in impervious bags for disposal or cleaning. Airline connections from airline respirators with HEPA disconnects and power cables from powered air-purifying respirators (PAPRs) will be disconnected just prior to entering the shower room.
Establishing Negative Pressure Within the Enclosure
Negative Pressure: Air is to be drawn into the enclosure under all anticipated conditions and exhausted through a HEPA filter for 24 hours a day during the entire duration of the project.
Air Flow Tests: Air flow patterns will be checked before removal operations begin, at least once per operating shift and any time there is a question regarding the integrity of the enclosure. The primary test for air flow is to trace air currents with smoke tubes or other visual methods. Flow checks are made at each opening and at each doorway to demonstrate that air is being drawn into the enclosure and at each worker's position to show that air is being drawn away from the breathing zone.
Monitoring Pressure Within the Enclosure: After the initial air flow patterns have been checked, the static pressure must be monitored within the enclosure. Monitoring may be made using manometers, pressure gauges, or combinations of these devices. It is recommended that they be attached to alarms and strip chart recorders at points identified by the design engineer.
Corrective Actions: If the manometers or pressure gauges demonstrate a reduction in pressure differential below the required level, work should cease and the reason for the change investigated and appropriate changes made. The air flow patterns should be retested before work begins again.
Pressure Differential: The design parameters for static pressure differentials between the inside and outside of enclosures typically range from 0.02 to 0.10 inches of water gauge, depending on conditions. All zones inside the enclosure must have less pressure than the ambient pressure outside of the enclosure (−0.02 inches water gauge differential). Design specifications for the differential vary according to the size, configuration, and shape of the enclosure as well as ambient and mechanical air pressure conditions around the enclosure.
Air Flow Patterns: The flow of air past each worker shall be enhanced by positioning the intakes and exhaust ports to remove contaminated air from the worker's breathing zone, by positioning HEPA vacuum cleaners to draw air from the worker's breathing zone, by forcing relatively uncontaminated air past the worker toward an exhaust port, or by using a combination of methods to reduce the worker's exposure.
Air Handling Unit Exhaust: The exhaust plume from air handling units should be located away from adjacent personnel and intakes for HVAC systems.
Air Flow Volume: The air flow volume (cubic meters per minute) exhausted (removed) from the workplace must exceed the amount of makeup air supplied to the enclosure. The rate of air exhausted from the enclosure should be designed to maintain a negative pressure in the enclosure and air movement past each worker. The volume of air flow removed from the enclosure should replace the volume of the container at every 5 to 15 minutes. Air flow volume will need to be relatively high for large enclosures, enclosures with awkward shapes, enclosures with multiple openings, and operations employing several workers in the enclosure.
Air Flow Velocity: At each opening, the air flow velocity must visibly “drag” air into the enclosure. The velocity of air flow within the enclosure must be adequate to remove airborne contamination from each worker's breathing zone without disturbing the asbestos-containing material on surfaces.
Airlocks: Airlocks are mechanisms on doors and curtains that control the air flow patterns in the doorways. If air flow occurs, the patterns through doorways must be such that the air flows toward the inside of the enclosure. Sometimes vestibules, double doors, or double curtains are used to prevent air movement through the doorways. To use a vestibule, a worker enters a chamber by opening the door or curtain and then closing the entry before opening the exit door or curtain.
Airlocks should be located between the equipment room and shower room, between the shower room and the clean room, and between the waste storage area and the outside of the enclosure. The air flow between adjacent rooms must be checked using smoke tubes or other visual tests to ensure the flow patterns draw air toward the work area without producing eddies.
Monitoring for Airborne Concentrations
In addition to the breathing zone samples taken as outlined in paragraph (f) of this section, samples of air should be taken to demonstrate the integrity of the enclosure, the cleanliness of the clean room and shower area, and the effectiveness of the HEPA filter. If the clean room is shown to be contaminated, the room must be relocated to an uncontaminated area.
Samples taken near the exhaust of portable ventilation systems must be done with care.
General Work Practices
Preventing dust dispersion is the primary means of controlling the spread of asbestos within the enclosure. Whenever practical, the point of removal should be isolated, enclosed, covered, or shielded from the workers in the area. Waste asbestos containing materials must be bagged during or immediately after removal; the material must remain saturated until the waste container is sealed.
Waste material with sharp points or corners must be placed in hard air-tight containers rather than bags.
Whenever possible, large components should be sealed in plastic sheeting and removed intact.
Bags or containers of waste will be moved to the waste holding area, washed, and wrapped in a bag with the appropriate labels.
Cleaning the Work Area
Surfaces within the work area should be kept free of visible dust and debris to the extent feasible. Whenever visible dust appears on surfaces, the surfaces within the enclosure must be cleaned by wiping with a wet sponge, brush, or cloth and then vacuumed with a HEPA vacuum.
All surfaces within the enclosure should be cleaned before the exhaust ventilation system is deactivated and the enclosure is disassembled. An approved encapsulant may be sprayed onto areas after the visible dust has been removed.
Appendix H to § 1926.1101—Substance Technical Information for Asbestos. Non-Mandatory
I. Substance Identification
A. Substance: “Asbestos” is the name of a class of magnesium-silicate minerals that occur in fibrous form. Minerals that are included in this group are chrysotile, crocidolite, amosite, anthophyllite asbestos, tremolite asbestos, and actinolite asbestos.
B. Asbestos is and was used in the manufacture of heat-resistant clothing, automotive brake and clutch linings, and a variety of building materials including floor tiles, roofing felts, ceiling tiles, asbestos-cement pipe and sheet, and fire-resistant drywall. Asbestos is also present in pipe and boiler insulation materials and in sprayed-on materials located on beams, in crawlspaces, and between walls.
C. The potential for an asbestos-containing product to release breathable fibers depends largely on its degree of friability. Friable means that the material can be crumbled with hand pressure and is therefore likely to emit fibers. The fibrous fluffy sprayed-on materials used for fireproofing, insulation, or sound proofing are considered to be friable, and they readily release airborne fibers if disturbed. Materials such as vinyl-asbestos floor tile or roofing felt are considered non-friable if intact and generally do not emit airborne fibers unless subjected to sanding, sawing and other aggressive operations. Asbestos-cement pipe or sheet can emit airborne fibers if the materials are cut or sawed, or if they are broken.
D. Permissible exposure: Exposure to airborne asbestos fibers may not exceed 0.1 fibers per cubic centimeter of air (0.1 f/cc) averaged over the 8-hour workday, and 1 fiber per cubic centimeter of air (1.0 f/cc) averaged over a 30 minute work period.
II. Health Hazard Data
A. Asbestos can cause disabling respiratory disease and various types of cancers if the fibers are inhaled. Inhaling or ingesting fibers from contaminated clothing or skin can also result in these diseases. The symptoms of these diseases generally do not appear for 20 or more years after initial exposure.
B. Exposure to asbestos has been shown to cause lung cancer, mesothelioma, and cancer of the stomach and colon. Mesothelioma is a rare cancer of the thin membrane lining of the chest and abdomen. Symptoms of mesothelioma include shortness of breath, pain in the walls of the chest, and/or abdominal pain.
III. Respirators and Protective Clothing
A. Respirators: You are required to wear a respirator when performing tasks that result in asbestos exposure that exceeds the permissible exposure limit (PEL) of 0.1 f/cc and when performing certain designated operations. Air-purifying respirators equipped with a high-efficiency particulate air (HEPA) filter can be used where airborne asbestos fiber concentrations do not exceed 1.0 f/cc; otherwise, more protective respirators such as air-supplied, positive-pressure, full facepiece respirators must be used. Disposable respirators or dust masks are not permitted to be used for asbestos work. For effective protection, respirators must fit your face and head snugly. Your employer is required to conduct a fit test when you are first assigned a respirator and every 6 months thereafter. Respirators should not be loosened or removed in work situations where their use is required.
B. Protective Clothing: You are required to wear protective clothing in work areas where asbestos fiber concentrations exceed the permissible exposure limit (PEL) of 0.1 f/cc.
IV. Disposal Procedures and Clean-up
A. Wastes that are generated by processes where asbestos is present include:
1. Empty asbestos shipping containers.
2. Process wastes such as cuttings, trimmings, or reject materials.
3. Housekeeping waste from wet-sweeping or HEPA-vacuuming.
4. Asbestos fireproofing or insulating material that is removed from buildings.
5. Asbestos-containing building products removed during building renovation or demolition.
6. Contaminated disposable protective clothing.
B. Empty shipping bags can be flattened under exhaust hoods and packed into airtight containers for disposal. Empty shipping drums are difficult to clean and should be sealed.
C. Vacuum bags or disposable paper filters should not be cleaned, but should be sprayed with a fine water mist and placed into a labeled waste container.
D. Process waste and housekeeping waste should be wetted with water or a mixture of water and surfactant prior to packaging in disposable containers.
E. Asbestos-containing material that is removed from buildings must be disposed of in leak-tight 6-mil plastic bags, plastic-lined cardboard containers, or plastic-lined metal containers. These wastes, which are removed while wet, should be sealed in containers before they dry out to minimize the release of asbestos fibers during handling.
V. Access to Information
A. Each year, your employer is required to inform you of the information contained in this standard and appendices for asbestos. In addition, your employer must instruct you in the proper work practices for handling asbestos-containing materials, and the correct use of protective equipment.
B. Your employer is required to determine whether you are being exposed to asbestos. Your employer must treat exposure to thermal system insulation and sprayed-on and troweled-on surfacing material as asbestos exposure, unless results of laboratory analysis show that the material does not contain asbestos. You or your representative has the right to observe employee measurements and to record the results obtained. Your employer is required to inform you of your exposure, and, if you are exposed above the permissible exposure limit, he or she is required to inform you of the actions that are being taken to reduce your exposure to within the permissible limit.
C. Your employer is required to keep records of your exposures and medical examinations. These exposure records must be kept for at least thirty (30) years. Medical records must be kept for the period of your employment plus thirty (30) years.
D. Your employer is required to release your exposure and medical records to your physician or designated representative upon your written request.
Appendix I to § 1926.1101—Medical Surveillance Guidelines for Asbestos, Non-Mandatory
I. Route of Entry
Inhalation, ingestion.
II. Toxicology
Clinical evidence of the adverse effects associated with exposure to asbestos is present in the form of several well-conducted epidemiological studies of occupationally exposed workers, family contacts of workers, and persons living near asbestos mines. These studies have shown a definite association between exposure to asbestos and an increased incidence of lung cancer, pleural and peritoneal mesothelioma, gastrointestinal cancer, and asbestosis. The latter is a disabling fibrotic lung disease that is caused only by exposure to asbestos. Exposure to asbestos has also been associated with an increased incidence of esophageal, kidney, laryngeal, pharyngeal, and buccal cavity cancers. As with other known chronic occupational diseases, disease associated with asbestos generally appears about 20 years following the first occurrence of exposure: There are no known acute effects associated with exposure to asbestos.
Epidemiological studies indicate that the risk of lung cancer among exposed workers who smoke cigarettes is greatly increased over the risk of lung cancer among non-exposed smokers or exposed nonsmokers. These studies suggest that cessation of smoking will reduce the risk of lung cancer for a person exposed to asbestos but will not reduce it to the same level of risk as that existing for an exposed worker who has never smoked.
III. Signs and Symptoms of Exposure-Related Disease
The signs and symptoms of lung cancer or gastrointestinal cancer induced by exposure to asbestos are not unique, except that a chest X-ray of an exposed patient with lung cancer may show pleural plaques, pleural calcification, or pleural fibrosis, and may also show asbestosis ( i.e., small irregular parenchymal opacities). Symptoms characteristic of mesothelioma include shortness of breath, pain in the chest or abdominal pain. Mesothelioma has a much longer average latency period compared with lung cancer (40 years versus 15-20 years), and mesothelioma is therefore more likely to be found among workers who were first exposed to asbestos at an early age. Mesothelioma is a fatal disease.
Asbestosis is pulmonary fibrosis caused by the accumulation of asbestos fibers in the lungs. Symptoms include shortness of breath, coughing, fatigue, and vague feelings of sickness. When the fibrosis worsens, shortness of breath occurs even at rest. The diagnosis of asbestosis is most commonly based on a history of exposure to asbestos, the presence of characteristic radiologic abnormalities, end-inspiratory crackles (rales), and other clinical features of fibrosing lung disease. Pleural plaques and thickening may be observed on chest X-rays. Asbestosis is often a progressive disease even in the absence of continued exposure, although this appears to be a highly individualized characteristic. In severe cases, death may be caused by respiratory or cardiac failure.
IV. Surveillance and Preventive Considerations
As noted above, exposure to asbestos has been linked to an increased risk of lung cancer, mesothelioma, gastrointestinal cancer, and asbestosis among occupationally exposed workers. Adequate screening tests to determine an employee's potential for developing serious chronic diseases, such as a cancer, from exposure to asbestos do not presently exist. However, some tests, particularly chest X-rays and pulmonary function tests, may indicate that an employee has been overexposed to asbestos increasing his or her risk of developing exposure related chronic diseases. It is important for the physician to become familiar with the operating conditions in which occupational exposure to asbestos is likely to occur. This is particularly important in evaluating medical and work histories and in conducting physical examinations. When an active employee has been identified as having been overexposed to asbestos measures taken by the employer to eliminate or mitigate further exposure should also lower the risk of serious long-term consequences.
The employer is required to institute a medical surveillance program for all employees who are or will be exposed to asbestos at or above the permissible exposure limit (0.1 fiber per cubic centimeter of air). All examinations and procedures must be performed by or under the supervision of a licensed physician, at a reasonable time and place, and at no cost to the employee.
Although broad latitude is given to the physician in prescribing specific tests to be included in the medical surveillance program, OSHA requires inclusion of the following elements in the routine examination:
The employer is required to make the prescribed tests available at least annually to those employees covered; more often than specified if recommended by the examining physician; and upon termination of employment.
The employer is required to provide the physician with the following information: A copy of this standard and appendices; a description of the employee's duties as they relate to asbestos exposure; the employee's representative level of exposure to asbestos; a description of any personal protective and respiratory equipment used; and information from previous medical examinations of the affected employee that is not otherwise available to the physician. Making this information available to the physician will aid in the evaluation of the employee's health in relation to assigned duties and fitness to wear personal protective equipment, if required.
The employer is required to obtain a written opinion from the examining physician containing the results of the medical examination; the physician's opinion as to whether the employee has any detected medical conditions that would place the employee at an increased risk of exposure-related disease; any recommended limitations on the employee or on the use of personal protective equipment; and a statement that the employee has been informed by the physician of the results of the medical examination and of any medical conditions related to asbestos exposure that require further explanation or treatment. This written opinion must not reveal specific findings or diagnoses unrelated to exposure to asbestos, and a copy of the opinion must be provided to the affected employee.
Appendix J to § 1926.1101—Smoking Cessation Program Information for Asbestos—Non-Mandatory
The following organizations provide smoking cessation information.
1. The National Cancer Institute operates a toll-free Cancer Information Service (CIS) with trained personnel to help you. Call 1-800-4-CANCER * to reach the CIS office serving your area, or write: Office of Cancer Communications, National Cancer Institute, National Institutes of Health, Building 31 Room 10A24, Bethesda, Maryland 20892.
2. American Cancer Society, 3340 Peachtree Road, N.E., Atlanta, Georgia 30026, (404) 320-3333
The American Cancer Society (ACS) is a voluntary organization composed of 58 divisions and 3,100 local units. Through “The Great American Smokeout” in November, the annual Cancer Crusade in April, and numerous educational materials, ACS helps people learn about the health hazards of smoking and become successful ex-smokers.
3. American Heart Association, 7320 Greenville Avenue, Dallas, Texas 75231, (214) 750-5300
The American Heart Association (AHA) is a voluntary organization with 130,000 members (physicians, scientists, and laypersons) in 55 state and regional groups. AHA produces a variety of publications and audiovisual materials about the effects of smoking on the heart. AHA also has developed a guidebook for incorporating a weight-control component into smoking cessation programs.
4. American Lung Association, 1740 Broadway, New York, New York 10019, (212) 245-8000
A voluntary organization of 7,500 members (physicians, nurses, and laypersons), the American Lung Association (ALA) conducts numerous public information programs about the health effects of smoking. ALA has 59 state and 85 local units. The organization actively supports legislation and information campaigns for non-smokers' rights and provides help for smokers who want to quit, for example, through “Freedom From Smoking,” a self-help smoking cessation program.
5. Office on Smoking and Health, U.S. Department of Health and Human Services, 5600 Fishers Lane, Park Building, Room 110, Rockville, Maryland 20857
The Office on Smoking and Health (OSH) is the Department of Health and Human Services' lead agency in smoking control. OSH has sponsored distribution of publications on smoking-related topics, such as free flyers on relapse after initial quitting, helping a friend or family member quit smoking, the health hazards of smoking, and the effects of parental smoking on teenagers.
* In Hawaii, on Oahu call 524-1234 (call collect from neighboring islands),
Spanish-speaking staff members are available during daytime hours to callers from the following areas: California, Florida, Georgia, Illinois, New Jersey (area code 201), New York, and Texas. Consult your local telephone directory for listings of local chapters.
Appendix K to § 1926.1101—Polarized Light Microscopy of Asbestos (Non-Mandatory)
Method number:
ID-191
Matrix: Bulk
Collection Procedure:
Collect approximately 1 to 2 grams of each type of material and place into separate 20 mL scintillation vials.
Analytical Procedure:
A portion of each separate phase is analyzed by gross examination, phase-polar examination, and central stop dispersion microscopy.
Commercial manufacturers and products mentioned in this method are for descriptive use only and do not constitute endorsements by USDOL-OSHA. Similar products from other sources may be substituted.
1. Introduction
This method describes the collection and analysis of asbestos bulk materials by light microscopy techniques including phase- polar illumination and central-stop dispersion microscopy. Some terms unique to asbestos analysis are defined below:
Amphibole: A family of minerals whose crystals are formed by long, thin units which have two thin ribbons of double chain silicate with a brucite ribbon in between. The shape of each unit is similar to an “I beam”. Minerals important in asbestos analysis include cummingtonite-grunerite, crocidolite, tremolite-actinolite and anthophyllite.
Asbestos: A term for naturally occurring fibrous minerals. Asbestos includes chrysotile, cummingtonite-grunerite asbestos (amosite), anthophyllite asbestos, tremolite asbestos, crocidolite, actinolite asbestos and any of these minerals which have been chemically treated or altered. The precise chemical formulation of each species varies with the location from which it was mined. Nominal compositions are listed:
| Chrysotile | Mg 3 Si 2 O 5 (OH) 4 |
|---|---|
| Crocidolite (Riebeckite asbestos) | Na 2 Fe 3 2 + Fe 2 3 + Si 8 O 22 (OH) 2 |
| Cummingtonite-Grunerite asbestos (Amosite) | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
| Tremolite-Actinolite asbestos | Ca 2 (Mg,Fe) 5 Si 8 O 22 (OH) 2 |
| Anthophyllite asbestos | (Mg,Fe) 7 Si 8 O 22 (OH) 2 |
Asbestos Fiber: A fiber of asbestos meeting the criteria for a fiber. (See section 3.5. of this Appendix)
Aspect Ratio: The ratio of the length of a fiber to its diameter usually defined as “length : width”, e.g. 3:1.
Brucite: A sheet mineral with the composition Mg(OH) 2.
Central Stop Dispersion Staining (microscope): This is a dark field microscope technique that images particles using only light refracted by the particle, excluding light that travels through the particle unrefracted. This is usually accomplished with a McCrone objective or other arrangement which places a circular stop with apparent aperture equal to the objective aperture in the back focal plane of the microscope.
Cleavage Fragments: Mineral particles formed by the comminution of minerals, especially those characterized by relatively parallel sides and moderate aspect ratio.
Differential Counting: The term applied to the practice of excluding certain kinds of fibers from a phase contrast asbestos count because they are not asbestos.
Fiber: A particle longer than or equal to 5 µm with a length to width ratio greater than or equal to 3:1. This may include cleavage fragments. (see section 3.5 of this appendix).
Phase Contrast: Contrast obtained in the microscope by causing light scattered by small particles to destructively interfere with unscattered light, thereby enhancing the visibility of very small particles and particles with very low intrinsic contrast.
Phase Contrast Microscope: A microscope configured with a phase mask pair to create phase contrast. The technique which uses this is called Phase Contrast Microscopy (PCM).
Phase-Polar Analysis: This is the use of polarized light in a phase contrast microscope. It is used to see the same size fibers that are visible in air filter analysis. Although fibers finer than 1 µm are visible, analysis of these is inferred from analysis of larger bundles that are usually present.
Phase-Polar Microscope: The phase-polar microscope is a phase contrast microscope which has an analyzer, a polarizer, a first order red plate and a rotating phase condenser all in place so that the polarized light image is enhanced by phase contrast.
Sealing Encapsulant: This is a product which can be applied, preferably by spraying, onto an asbestos surface which will seal the surface so that fibers cannot be released.
Serpentine: A mineral family consisting of minerals with the general composition Mg 3 (Si 2 O 5 (OH) 4 having the magnesium in brucite layer over a silicate layer. Minerals important in asbestos analysis included in this family are chrysotile, lizardite, antigorite.
1.1. History
Light microscopy has been used for well over 100 years for the determination of mineral species. This analysis is carried out using specialized polarizing microscopes as well as bright field microscopes. The identification of minerals is an on-going process with many new minerals described each year. The first recorded use of asbestos was in Finland about 2500 B.C. where the material was used in the mud wattle for the wooden huts the people lived in as well as strengthening for pottery. Adverse health aspects of the mineral were noted nearly 2000 years ago when Pliny the Younger wrote about the poor health of slaves in the asbestos mines. Although known to be injurious for centuries, the first modern references to its toxicity were by the British Labor Inspectorate when it banned asbestos dust from the workplace in 1898. Asbestosis cases were described in the literature after the turn of the century. Cancer was first suspected in the mid 1930's and a causal link to mesothelioma was made in 1965. Because of the public concern for worker and public safety with the use of this material, several different types of analysis were applied to the determination of asbestos content. Light microscopy requires a great deal of experience and craft. Attempts were made to apply less subjective methods to the analysis. X-ray diffraction was partially successful in determining the mineral types but was unable to separate out the fibrous portions from the non-fibrous portions. Also, the minimum detection limit for asbestos analysis by X-ray diffraction (XRD) is about 1%. Differential Thermal Analysis (DTA) was no more successful. These provide useful corroborating information when the presence of asbestos has been shown by microscopy; however, neither can determine the difference between fibrous and non-fibrous minerals when both habits are present. The same is true of Infrared Absorption (IR).
When electron microscopy was applied to asbestos analysis, hundreds of fibers were discovered present too small to be visible in any light microscope. There are two different types of electron microscope used for asbestos analysis: Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). Scanning Electron Microscopy is useful in identifying minerals. The SEM can provide two of the three pieces of information required to identify fibers by electron microscopy: morphology and chemistry. The third is structure as determined by Selected Area Electron Diffraction—SAED which is performed in the TEM. Although the resolution of the SEM is sufficient for very fine fibers to be seen, accuracy of chemical analysis that can be performed on the fibers varies with fiber diameter in fibers of less than 0.2 µm diameter. The TEM is a powerful tool to identify fibers too small to be resolved by light microscopy and should be used in conjunction with this method when necessary. The TEM can provide all three pieces of information required for fiber identification. Most fibers thicker than 1 µm can adequately be defined in the light microscope. The light microscope remains as the best instrument for the determination of mineral type. This is because the minerals under investigation were first described analytically with the light microscope. It is inexpensive and gives positive identification for most samples analyzed. Further, when optical techniques are inadequate, there is ample indication that alternative techniques should be used for complete identification of the sample.
1.2. Principle
Minerals consist of atoms that may be arranged in random order or in a regular arrangement. Amorphous materials have atoms in random order while crystalline materials have long range order. Many materials are transparent to light, at least for small particles or for thin sections. The properties of these materials can be investigated by the effect that the material has on light passing through it. The six asbestos minerals are all crystalline with particular properties that have been identified and cataloged. These six minerals are anisotropic. They have a regular array of atoms, but the arrangement is not the same in all directions. Each major direction of the crystal presents a different regularity. Light photons travelling in each of these main directions will encounter different electrical neighborhoods, affecting the path and time of travel. The techniques outlined in this method use the fact that light traveling through fibers or crystals in different directions will behave differently, but predictably. The behavior of the light as it travels through a crystal can be measured and compared with known or determined values to identify the mineral species. Usually, Polarized Light Microscopy (PLM) is performed with strain-free objectives on a bright-field microscope platform. This would limit the resolution of the microscope to about 0.4 µm. Because OSHA requires the counting and identification of fibers visible in phase contrast, the phase contrast platform is used to visualize the fibers with the polarizing elements added into the light path. Polarized light methods cannot identify fibers finer than about 1 µm in diameter even though they are visible. The finest fibers are usually identified by inference from the presence of larger, identifiable fiber bundles. When fibers are present, but not identifiable by light microscopy, use either SEM or TEM to determine the fiber identity.
1.3. Advantages and Disadvantages
The advantages of light microcopy are:
The minerals present can exist in asbestiform, fibrous, prismatic, or massive varieties all at the same time. Therefore, bulk methods of analysis such as X-ray diffraction, IR analysis, DTA, etc. are inappropriate where the material is not known to be fibrous.
The disadvantages are:
1.4. Method Performance
1.4.1. This method can be used for determination of asbestos content from 0 to 100% asbestos. The detection limit has not been adequately determined, although for selected samples, the limit is very low, depending on the number of particles examined. For mostly homogeneous, finely divided samples, with no difficult fibrous interferences, the detection limit is below 1%. For inhomogeneous samples (most samples), the detection limit remains undefined. NIST has conducted proficiency testing of laboratories on a national scale. Although each round is reported statistically with an average, control limits, etc., the results indicate a difficulty in establishing precision especially in the low concentration range. It is suspected that there is significant bias in the low range especially near 1%. EPA tried to remedy this by requiring a mandatory point counting scheme for samples less than 10%. The point counting procedure is tedious, and may introduce significant biases of its own. It has not been incorporated into this method.
1.4.2. The precision and accuracy of the quantitation tests performed in this method are unknown. Concentrations are easier to determine in commercial products where asbestos was deliberately added because the amount is usually more than a few percent. An analyst's results can be “calibrated” against the known amounts added by the manufacturer. For geological samples, the degree of homogeneity affects the precision.
1.4.3. The performance of the method is analyst dependent. The analyst must choose carefully and not necessarily randomly the portions for analysis to assure that detection of asbestos occurs when it is present. For this reason, the analyst must have adequate training in sample preparation, and experience in the location and identification of asbestos in samples. This is usually accomplished through substantial on-the-job training as well as formal education in mineralogy and microscopy.
1.5. Interferences
Any material which is long, thin, and small enough to be viewed under the microscope can be considered an interference for asbestos. There are literally hundreds of interferences in workplaces. The techniques described in this method are normally sufficient to eliminate the interferences. An analyst's success in eliminating the interferences depends on proper training.
Asbestos minerals belong to two mineral families: the serpentines and the amphiboles. In the serpentine family, the only common fibrous mineral is chrysotile. Occasionally, the mineral antigorite occurs in a fibril habit with morphology similar to the amphiboles. The amphibole minerals consist of a score of different minerals of which only five are regulated by federal standard: amosite, crocidolite, anthophyllite asbestos, tremolite asbestos and actinolite asbestos. These are the only amphibole minerals that have been commercially exploited for their fibrous properties; however, the rest can and do occur occasionally in asbestiform habit.
In addition to the related mineral interferences, other minerals common in building material may present a problem for some microscopists: gypsum, anhydrite, brucite, quartz fibers, talc fibers or ribbons, wollastonite, perlite, attapulgite, etc. Other fibrous materials commonly present in workplaces are: fiberglass, mineral wool, ceramic wool, refractory ceramic fibers, kevlar, nomex, synthetic fibers, graphite or carbon fibers, cellulose (paper or wood) fibers, metal fibers, etc.
Matrix embedding material can sometimes be a negative interference. The analyst may not be able to easily extract the fibers from the matrix in order to use the method. Where possible, remove the matrix before the analysis, taking careful note of the loss of weight. Some common matrix materials are: vinyl, rubber, tar, paint, plant fiber, cement, and epoxy. A further negative interference is that the asbestos fibers themselves may be either too small to be seen in Phase contrast Microscopy (PCM) or of a very low fibrous quality, having the appearance of plant fibers. The analyst's ability to deal with these materials increases with experience.
1.6. Uses and Occupational Exposure
Asbestos is ubiquitous in the environment. More than 40% of the land area of the United States is composed of minerals which may contain asbestos. Fortunately, the actual formation of great amounts of asbestos is relatively rare. Nonetheless, there are locations in which environmental exposure can be severe such as in the Serpentine Hills of California.
There are thousands of uses for asbestos in industry and the home. Asbestos abatement workers are the most current segment of the population to have occupational exposure to great amounts of asbestos. If the material is undisturbed, there is no exposure. Exposure occurs when the asbestos-containing material is abraded or otherwise disturbed during maintenance operations or some other activity. Approximately 95% of the asbestos in place in the United States is chrysotile.
Amosite and crocidolite make up nearly all the difference. Tremolite and anthophyllite make up a very small percentage. Tremolite is found in extremely small amounts in certain chrysotile deposits. Actinolite exposure is probably greatest from environmental sources, but has been identified in vermiculite containing, sprayed-on insulating materials which may have been certified as asbestos-free.
1.7. Physical and Chemical Properties
The nominal chemical compositions for the asbestos minerals were given in Section 1. Compared to cleavage fragments of the same minerals, asbestiform fibers possess a high tensile strength along the fiber axis. They are chemically inert, non-combustible, and heat resistant. Except for chrysotile, they are insoluble in Hydrochloric acid (HCl). Chrysotile is slightly soluble in HCl. Asbestos has high electrical resistance and good sound absorbing characteristics. It can be woven into cables, fabrics or other textiles, or matted into papers, felts, and mats.
1.8. Toxicology (This section is for Information Only and Should Not Be Taken as OSHA Policy)
Possible physiologic results of respiratory exposure to asbestos are mesothelioma of the pleura or peritoneum, interstitial fibrosis, asbestosis, pneumoconiosis, or respiratory cancer. The possible consequences of asbestos exposure are detailed in the NIOSH Criteria Document or in the OSHA Asbestos Standards 29 CFR 1910.1001 and 29 CFR 1926.1101 and 29 CFR 1915.1001.
2. Sampling Procedure
2.1. Equipment for sampling
2.2. Safety Precautions
Asbestos is a known carcinogen. Take care when sampling. While in an asbestos-containing atmosphere, a properly selected and fit-tested respirator should be worn. Take samples in a manner to cause the least amount of dust. Follow these general guidelines:
2.3. Sampling Procedure
Samples of any suspect material should be taken from an inconspicuous place. Where the material is to remain, seal the sampling wound with an encapsulant to eliminate the potential for exposure from the sample site. Microscopy requires only a few milligrams of material. The amount that will fill a 20 mL scintillation vial is more than adequate. Be sure to collect samples from all layers and phases of material. If possible, make separate samples of each different phase of the material. This will aid in determining the actual hazard. DO NOT USE ENVELOPES, PLASTIC OR PAPER BAGS OF ANY KIND TO COLLECT SAMPLES. The use of plastic bags presents a contamination hazard to laboratory personnel and to other samples. When these containers are opened, a bellows effect blows fibers out of the container onto everything, including the person opening the container.
If a cork-borer type sampler is available, push the tube through the material all the way, so that all layers of material are sampled. Some samplers are intended to be disposable. These should be capped and sent to the laboratory. If a non-disposable cork borer is used, empty the contents into a scintillation vial and send to the laboratory. Vigorously and completely clean the cork borer between samples.
2.4 Shipment
Samples packed in glass vials must not touch or they might break in shipment.
3. Analysis
The analysis of asbestos samples can be divided into two major parts: sample preparation and microscopy. Because of the different asbestos uses that may be encountered by the analyst, each sample may need different preparation steps. The choices are outlined below. There are several different tests that are performed to identify the asbestos species and determine the percentage. They will be explained below.
3.1. Safety
Handle the samples in HEPA-filter equipped hoods. If samples are received in bags, envelopes or other inappropriate container, open them only in a hood having a face velocity at or greater than 100 fpm. Transfer a small amount to a scintillation vial and only handle the smaller amount.
Take care not to get this material on the skin. Wash immediately with soap and water if this happens.
3.2. Equipment
n = 1.550
n = 1.585
n = 1.590
n = 1.605
n = 1.620
n = 1.670
n = 1.680
n = 1.690
Tetrasodium
0.7 g/l
Sodium Potassium Tartrate
8.0 mg/liter
Hydrochloric Acid
99.2 g/liter
Sodium Tartrate
0.14 g/liter
3.3. Sample Pre-Preparation
Sample preparation begins with pre-preparation which may include chemical reduction of the matrix, heating the sample to dryness or heating in the muffle furnace. The end result is a sample which has been reduced to a powder that is sufficiently fine to fit under the cover slip. Analyze different phases of samples separately, e.g., tile and the tile mastic should be analyzed separately as the mastic may contain asbestos while the tile may not.
Samples with a high water content will not give the proper dispersion colors and must be dried prior to sample mounting. Remove the lid of the scintillation vial, place the bottle in the drying oven and heat at 100 °C to dryness (usually about 2 h). Samples which are not submitted to the lab in glass must be removed and placed in glass vials or aluminum weighing pans before placing them in the drying oven.
These may include samples with tar as a matrix, vinyl asbestos tile, or any other organic that can be reduced by heating. Remove the sample from the vial and weigh in a balance to determine the weight of the submitted portion. Place the sample in a muffle furnace at 500 °C for 1 to 2 h or until all obvious organic material has been removed. Retrieve, cool and weigh again to determine the weight loss on ignition. This is necessary to determine the asbestos content of the submitted sample, because the analyst will be looking at a reduced sample.
Vinyl asbestos tile is the most common material treated with this solvent, although, substances containing tar will sometimes yield to this treatment. Select a portion of the material and then grind it up if possible. Weigh the sample and place it in a test tube. Add sufficient THF to dissolve the organic matrix. This is usually about 4 to 5 mL. Remember, THF is highly flammable. Filter the remaining material through a tared silver membrane, dry and weigh to determine how much is left after the solvent extraction. Further process the sample to remove carbonate or mount directly.
Carbonate material is often found on fibers and sometimes must be removed in order to perform dispersion microscopy. Weigh out a portion of the material and place it in a test tube. Add a sufficient amount of 0.1 M HCl or decalcifying solution in the tube to react all the carbonate as evidenced by gas formation; i.e., when the gas bubbles stop, add a little more solution. If no more gas forms, the reaction is complete. Filter the material out through a tared silver membrane, dry and weigh to determine the weight lost.
3.4. Sample Preparation
Samples must be prepared so that accurate determination can be made of the asbestos type and amount present. The following steps are carried out in the low-flow hood (a low-flow hood has less than 50 fpm flow):
The preparation tools should either be disposable or cleaned thoroughly. Use vigorous scrubbing to loosen the fibers during the washing. Rinse the implements with copious amounts of water and air-dry in a dust-free environment.
Treat at least two different areas of each phase in this fashion. Choose representative areas of the sample. It may be useful to select particular areas or fibers for analysis. This is useful to identify asbestos in severely inhomogeneous samples.
When it is determined that amphiboles may be present, repeat the above process using the appropriate high-dispersion oils until an identification is made or all six asbestos minerals have been ruled out. Note that percent determination must be done in the index medium 1.550 because amphiboles tend to disappear in their matching mediums.
3.5. Analytical procedure
The analysis consists of three parts: The determination of whether there is asbestos present, what type is present and the determination of how much is present. The general flow of the analysis is:
Examination by Becke line analysis may also be used; however, this is usually more cumbersome for asbestos determination.
Identification of a particle as asbestos requires that it be asbestiform. Description of particles should follow the suggestion of Campbell. (Figure 1)
For the purpose of regulation, the mineral must be one of the six minerals covered and must be in the asbestos growth habit. Large specimen samples of asbestos generally have the gross appearance of wood. Fibers are easily parted from it. Asbestos fibers are very long compared with their widths. The fibers have a very high tensile strength as demonstrated by bending without breaking. Asbestos fibers exist in bundles that are easily parted, show longitudinal fine structure and may be tufted at the ends showing “bundle of sticks” morphology. In the microscope some of these properties may not be observable. Amphiboles do not always show striations along their length even when they are asbestos. Neither will they always show tufting. They generally do not show a curved nature except for very long fibers. Asbestos and asbestiform minerals are usually characterized in groups by extremely high aspect ratios (greater than 100:1). While aspect ratio analysis is useful for characterizing populations of fibers, it cannot be used to identify individual fibers of intermediate to short aspect ratio. Observation of many fibers is often necessary to determine whether a sample consists of “cleavage fragments” or of asbestos fibers.
Most cleavage fragments of the asbestos minerals are easily distinguishable from true asbestos fibers. This is because true cleavage fragments usually have larger diameters than 1 µm. Internal structure of particles larger than this usually shows them to have no internal fibrillar structure. In addition, cleavage fragments of the monoclinic amphiboles show inclined extinction under crossed polars with no compensator. Asbestos fibers usually show extinction at zero degrees or ambiguous extinction if any at all. Morphologically, the larger cleavage fragments are obvious by their blunt or stepped ends showing prismatic habit. Also, they tend to be acicular rather than filiform.
Where the particles are less than 1 µm in diameter and have an aspect ratio greater than or equal to 3:1, it is recommended that the sample be analyzed by SEM or TEM if there is any question whether the fibers are cleavage fragments or asbestiform particles.
Care must be taken when analyzing by electron microscopy because the interferences are different from those in light microscopy and may structurally be very similar to asbestos. The classic interference is between anthophyllite and biopyribole or intermediate fiber. Use the same morphological clues for electron microscopy as are used for light microscopy, e.g. fibril splitting, internal longitudinal striation, fraying, curvature, etc.
Examine the sample, preferably in the glass vial. Determine the presence of any obvious fibrous component. Estimate a percentage based on previous experience and current observation. Determine whether any pre-preparation is necessary. Determine the number of phases present. This step may be carried out or augmented by observation at 6 to 40 × under a stereo microscope.
| Type of asbestos | Index of refraction |
|---|---|
| Chrysotile | n = 1.550. |
| Amosite | n = 1.670 or 1.680. |
| Crocidolite | n = 1.690. |
| Anthophyllite | n = 1.605 and 1.620. |
| Tremolite | n = 1.605 and 1.620. |
| Actinolite | n = 1.620. |
Where more than one liquid is suggested, the first is preferred; however, in some cases this liquid will not give good dispersion color. Take care to avoid interferences in the other liquid; e.g., wollastonite in n = 1.620 will give the same colors as tremolite. In n = 1.605 wollastonite will appear yellow in all directions. Wollastonite may be determined under crossed polars as it will change from blue to yellow as it is rotated along its fiber axis by tapping on the cover slip. Asbestos minerals will not change in this way.
Determination of the angle of extinction may, when present, aid in the determination of anthophyllite from tremolite. True asbestos fibers usually have 0° extinction or ambiguous extinction, while cleavage fragments have more definite extinction.
Continue analysis until both preparations have been examined and all present species of asbestos are identified. If there are no fibers present, or there is less than 0.1% present, end the analysis with the minimum number of slides (2).
View all of the area under the cover slip to make the percentage determination. View the fields while moving the stage, paying attention to the clumps of material. These are not usually the best areas to perform dispersion microscopy because of the interference from other materials. But, they are the areas most likely to represent the accurate percentage in the sample. Small amounts of asbestos require slower scanning and more frequent analysis of individual fields.
Report the area occluded by asbestos as the concentration. This estimate does not generally take into consideration the difference in density of the different species present in the sample. For most samples this is adequate. Simulation studies with similar materials must be carried out to apply microvisual estimation for that purpose and is beyond the scope of this procedure.
Step 1. 60% remains after heating at 550 °C for 1 h.
Step 2. 30% of the residue of step 1 remains after dissolution of carbonate in 0.1 m HCl.
Step 3. Microvisual estimation determines that 5% of the sample is chrysotile asbestos.
The reported result is:
R = (Microvisual result in percent) × (Fraction remaining after step 2) × (Fraction remaining of original sample after step 1)
R = (5) × (.30) × (.60) = 0.9%
For samples where asbestos was identified, but is less than 1.0%, report “Asbestos present, less than 1.0%.” There must have been at least two observed fibers or fiber bundles in the two preparations to be reported as present. For samples where asbestos was not seen, report as “None Detected.”
[51 FR 22756, June 20, 1986]
Editorial Note:
Federal Register
www.govinfo.gov.
Auxiliary Information
Because of the subjective nature of asbestos analysis, certain concepts and procedures need to be discussed in more depth. This information will help the analyst understand why some of the procedures are carried out the way they are.
4.1. Light
Light is electromagnetic energy. It travels from its source in packets called quanta. It is instructive to consider light as a plane wave. The light has a direction of travel. Perpendicular to this and mutually perpendicular to each other, are two vector components. One is the magnetic vector and the other is the electric vector. We shall only be concerned with the electric vector. In this description, the interaction of the vector and the mineral will describe all the observable phenomena. From a light source such a microscope illuminator, light travels in all different direction from the filament.
In any given direction away from the filament, the electric vector is perpendicular to the direction of travel of a light ray. While perpendicular, its orientation is random about the travel axis. If the electric vectors from all the light rays were lined up by passing the light through a filter that would only let light rays with electric vectors oriented in one direction pass, the light would then be POLARIZED.
Polarized light interacts with matter in the direction of the electric vector. This is the polarization direction. Using this property it is possible to use polarized light to probe different materials and identify them by how they interact with light.
The speed of light in a vacuum is a constant at about 2.99 × 10 8 m/s. When light travels in different materials such as air, water, minerals or oil, it does not travel at this speed. It travels slower. This slowing is a function of both the material through which the light is traveling and the wavelength or frequency of the light. In general, the more dense the material, the slower the light travels. Also, generally, the higher the frequency, the slower the light will travel. The ratio of the speed of light in a vacuum to that in a material is called the index of refraction (n). It is usually measured at 589 nm (the sodium D line). If white light (light containing all the visible wavelengths) travels through a material, rays of longer wavelengths will travel faster than those of shorter wavelengths, this separation is called dispersion. Dispersion is used as an identifier of materials as described in Section 4.6.
4.2. Material Properties
Materials are either amorphous or crystalline. The difference between these two descriptions depends on the positions of the atoms in them. The atoms in amorphous materials are randomly arranged with no long range order. An example of an amorphous material is glass. The atoms in crystalline materials, on the other hand, are in regular arrays and have long range order. Most of the atoms can be found in highly predictable locations. Examples of crystalline material are salt, gold, and the asbestos minerals.
It is beyond the scope of this method to describe the different types of crystalline materials that can be found, or the full description of the classes into which they can fall. However, some general crystallography is provided below to give a foundation to the procedures described.
With the exception of anthophyllite, all the asbestos minerals belong to the monoclinic crystal type. The unit cell is the basic repeating unit of the crystal and for monoclinic crystals can be described as having three unequal sides, two 90° angles and one angle not equal to 90°. The orthorhombic group, of which anthophyllite is a member has three unequal sides and three 90° angles. The unequal sides are a consequence of the complexity of fitting the different atoms into the unit cell. Although the atoms are in a regular array, that array is not symmetrical in all directions. There is long range order in the three major directions of the crystal. However, the order is different in each of the three directions. This has the effect that the index of refraction is different in each of the three directions. Using polarized light, we can investigate the index of refraction in each of the directions and identify the mineral or material under investigation. The indices α, β, and γ are used to identify the lowest, middle, and highest index of refraction respectively. The x direction, associated with α is called the fast axis. Conversely, the z direction is associated with γ and is the slow direction. Crocidolite has α along the fiber length making it “length-fast”. The remainder of the asbestos minerals have the γ axis along the fiber length. They are called “length-slow”. This orientation to fiber length is used to aid in the identification of asbestos.
4.3. Polarized Light Technique
Polarized light microscopy as described in this section uses the phase-polar microscope described in Section 3.2. A phase contrast microscope is fitted with two polarizing elements, one below and one above the sample. The polarizers have their polarization directions at right angles to each other. Depending on the tests performed, there may be a compensator between these two polarizing elements. A compensator is a piece of mineral with known properties that “compensates” for some deficiency in the optical train. Light emerging from a polarizing element has its electric vector pointing in the polarization direction of the element. The light will not be subsequently transmitted through a second element set at a right angle to the first element. Unless the light is altered as it passes from one element to the other, there is no transmission of light.
4.4. Angle of Extinction
Crystals which have different crystal regularity in two or three main directions are said to be anisotropic. They have a different index of refraction in each of the main directions. When such a crystal is inserted between the crossed polars, the field of view is no longer dark but shows the crystal in color. The color depends on the properties of the crystal. The light acts as if it travels through the crystal along the optical axes. If a crystal optical axis were lined up along one of the polarizing directions (either the polarizer or the analyzer) the light would appear to travel only in that direction, and it would blink out or go dark. The difference in degrees between the fiber direction and the angle at which it blinks out is called the angle of extinction. When this angle can be measured, it is useful in identifying the mineral. The procedure for measuring the angle of extinction is to first identify the polarization direction in the microscope. A commercial alignment slide can be used to establish the polarization directions or use anthophyllite or another suitable mineral. This mineral has a zero degree angle of extinction and will go dark to extinction as it aligns with the polarization directions. When a fiber of anthophyllite has gone to extinction, align the eyepiece reticle or graticule with the fiber so that there is a visual cue as to the direction of polarization in the field of view. Tape or otherwise secure the eyepiece in this position so it will not shift.
After the polarization direction has been identified in the field of view, move the particle of interest to the center of the field of view and align it with the polarization direction. For fibers, align the fiber along this direction. Note the angular reading of the rotating stage. Looking at the particle, rotate the stage until the fiber goes dark or “blinks out”. Again note the reading of the stage. The difference in the first reading and the second is an angle of extinction.
The angle measured may vary as the orientation of the fiber changes about its long axis. Tables of mineralogical data usually report the maximum angle of extinction. Asbestos forming minerals, when they exhibit an angle of extinction, usually do show an angle of extinction close to the reported maximum, or as appropriate depending on the substitution chemistry.
4.5. Crossed Polars with Compensator
When the optical axes of a crystal are not lined up along one of the polarizing directions (either the polarizer or the analyzer) part of the light travels along one axis and part travels along the other visible axis. This is characteristic of birefringent materials.
The color depends on the difference of the two visible indices of refraction and the thickness of the crystal. The maximum difference available is the difference between the α and the γ axes. This maximum difference is usually tabulated as the birefringence of the crystal.
For this test, align the fiber at 45° to the polarization directions in order to maximize the contribution to each of the optical axes. The colors seen are called retardation colors. They arise from the recombination of light which has traveled through the two separate directions of the crystal. One of the rays is retarded behind the other since the light in that direction travels slower. On recombination, some of the colors which make up white light are enhanced by constructive interference and some are suppressed by destructive interference. The result is a color dependent on the difference between the indices and the thickness of the crystal. The proper colors, thicknesses, and retardations are shown on a Michel-Levy chart. The three items, retardation, thickness and birefringence are related by the following relationship:
γ
α
R = retardation, t = crystal thickness in µm, and
α,γ
Examination of the equation for asbestos minerals reveals that the visible colors for almost all common asbestos minerals and fiber sizes are shades of gray and black. The eye is relatively poor at discriminating different shades of gray. It is very good at discriminating different colors. In order to compensate for the low retardation, a compensator is added to the light train between the polarization elements. The compensator used for this test is a gypsum plate of known thickness and birefringence. Such a compensator when oriented at 45° to the polarizer direction, provides a retardation of 530 nm of the 530 nm wavelength color. This enhances the red color and gives the background a characteristic red to red-magenta color. If this “full-wave” compensator is in place when the asbestos preparation is inserted into the light train, the colors seen on the fibers are quite different. Gypsum, like asbestos has a fast axis and a slow axis. When a fiber is aligned with its fast axis in the same direction as the fast axis of the gypsum plate, the ray vibrating in the slow direction is retarded by both the asbestos and the gypsum. This results in a higher retardation than would be present for either of the two minerals. The color seen is a second order blue. When the fiber is rotated 90° using the rotating stage, the slow direction of the fiber is now aligned with the fast direction of the gypsum and the fast direction of the fiber is aligned with the slow direction of the gypsum. Thus, one ray vibrates faster in the fast direction of the gypsum, and slower in the slow direction of the fiber; the other ray will vibrate slower in the slow direction of the gypsum and faster in the fast direction of the fiber. In this case, the effect is subtractive and the color seen is a first order yellow. As long as the fiber thickness does not add appreciably to the color, the same basic colors will be seen for all asbestos types except crocidolite. In crocidolite the colors will be weaker, may be in the opposite directions, and will be altered by the blue absorption color natural to crocidolite. Hundreds of other materials will give the same colors as asbestos, and therefore, this test is not definitive for asbestos. The test is useful in discriminating against fiberglass or other amorphous fibers such as some synthetic fibers. Certain synthetic fibers will show retardation colors different than asbestos; however, there are some forms of polyethylene and aramid which will show morphology and retardation colors similar to asbestos minerals. This test must be supplemented with a positive identification test when birefringent fibers are present which can not be excluded by morphology. This test is relatively ineffective for use on fibers less than 1 µm in diameter. For positive confirmation TEM or SEM should be used if no larger bundles or fibers are visible.
4.6. Dispersion Staining
Dispersion microscopy or dispersion staining is the method of choice for the identification of asbestos in bulk materials. Becke line analysis is used by some laboratories and yields the same results as does dispersion staining for asbestos and can be used in lieu of dispersion staining. Dispersion staining is performed on the same platform as the phase-polar analysis with the analyzer and compensator removed. One polarizing element remains to define the direction of the light so that the different indices of refraction of the fibers may be separately determined. Dispersion microscopy is a dark-field technique when used for asbestos. Particles are imaged with scattered light. Light which is unscattered is blocked from reaching the eye either by the back field image mask in a McCrone objective or a back field image mask in the phase condenser. The most convenient method is to use the rotating phase condenser to move an oversized phase ring into place. The ideal size for this ring is for the central disk to be just larger than the objective entry aperture as viewed in the back focal plane. The larger the disk, the less scattered light reaches the eye. This will have the effect of diminishing the intensity of dispersion color and will shift the actual color seen. The colors seen vary even on microscopes from the same manufacturer. This is due to the different bands of wavelength exclusion by different mask sizes. The mask may either reside in the condenser or in the objective back focal plane. It is imperative that the analyst determine by experimentation with asbestos standards what the appropriate colors should be for each asbestos type. The colors depend also on the temperature of the preparation and the exact chemistry of the asbestos. Therefore, some slight differences from the standards should be allowed. This is not a serious problem for commercial asbestos uses. This technique is used for identification of the indices of refraction for fibers by recognition of color. There is no direct numerical readout of the index of refraction. Correlation of color to actual index of refraction is possible by referral to published conversion tables. This is not necessary for the analysis of asbestos. Recognition of appropriate colors along with the proper morphology are deemed sufficient to identify the commercial asbestos minerals. Other techniques including SEM, TEM, and XRD may be required to provide additional information in order to identify other types of asbestos.
Make a preparation in the suspected matching high dispersion oil, e.g., n = 1.550 for chrysotile. Perform the preliminary tests to determine whether the fibers are birefringent or not. Take note of the morphological character. Wavy fibers are indicative of chrysotile while long, straight, thin, frayed fibers are indicative of amphibole asbestos. This can aid in the selection of the appropriate matching oil. The microscope is set up and the polarization direction is noted as in Section 4.4. Align a fiber with the polarization direction. Note the color. This is the color parallel to the polarizer. Then rotate the fiber rotating the stage 90° so that the polarization direction is across the fiber. This is the perpendicular position. Again note the color. Both colors must be consistent with standard asbestos minerals in the correct direction for a positive identification of asbestos. If only one of the colors is correct while the other is not, the identification is not positive. If the colors in both directions are bluish-white, the analyst has chosen a matching index oil which is higher than the correct matching oil, e.g. the analyst has used n = 1.620 where chrysotile is present. The next lower oil (Section 3.5.) should be used to prepare another specimen. If the color in both directions is yellow-white to straw-yellow-white, this indicates that the index of the oil is lower than the index of the fiber, e.g. the preparation is in n = 1.550 while anthophyllite is present. Select the next higher oil (Section 3.5.) and prepare another slide. Continue in this fashion until a positive identification of all asbestos species present has been made or all possible asbestos species have been ruled out by negative results in this test. Certain plant fibers can have similar dispersion colors as asbestos. Take care to note and evaluate the morphology of the fibers or remove the plant fibers in pre-preparation. Coating material on the fibers such as carbonate or vinyl may destroy the dispersion color. Usually, there will be some outcropping of fiber which will show the colors sufficient for identification. When this is not the case, treat the sample as described in Section 3.3. and then perform dispersion staining. Some samples will yield to Becke line analysis if they are coated or electron microscopy can be used for identification.
5. References
Asbestos in Air,
Dana's Textbook of Mineralogy;
Asbestos and Disease,
Women Inspectors of Factories.
Asbestos and Disease,
Selected Silicate Minerals and Their Asbestiform Varieties,
Asbestos,
National Emission Standards for Hazardous Air Pollutants; Asbestos NESHAP Revision,
Federal Register,
The Asbestos Minerals: Definitions, Description, Modes of Formation, Physical and Chemical Properties and Health Risk to the Mining Community,
J. Occ Medicine,
Occupational Exposure to Asbestos—1972,
Characteristics for Tremolite Fragments and Fibers,
5.13. Mefford, D., DCM Laboratory, Denver, private communication, July 1987.
Rock Forming Minerals,
Optical Mineralogy;
Amphiboles and Other Hydrous Pyriboles—Mineralogy, Reviews in Mineralogy,
Applications of Optical Microscopy in the Analysis of Asbestos
5.18. Polarized Light Microscopy, McCrone Research Institute, Chicago, 1976.
5.19. Asbestos Identification, McCrone Research Institute, G & G printers, Chicago, 1987.
5.20. McCrone, W.C., Calculation of Refractive Indices from Dispersion Staining Data, The Microscope, No 37, Chicago, 1989.
Asbestos and Other Health Related Silicates,
Geology of Asbestos Deposits,
Asbestos: Properties, Applications and Hazards,
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
[61 FR 31433, June 20, 1996]
As used in this standard:
Action level means a concentration of airborne beryllium of 0.1 micrograms per cubic meter of air (µg/m 3 ) calculated as an 8-hour time-weighted average (TWA).
Airborne exposure and airborne exposure to beryllium mean the exposure to airborne beryllium that would occur if the employee were not using a respirator.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, United States Department of Labor, or designee.
Beryllium lymphocyte proliferation test (BeLPT) means the measurement of blood lymphocyte proliferation in a laboratory test when lymphocytes are challenged with a soluble beryllium salt.
Beryllium sensitization means a response in the immune system of a specific individual who has been exposed to beryllium. There are no associated physical or clinical symptoms and no illness or disability with beryllium sensitization alone, but the response that occurs through beryllium sensitization can enable the immune system to recognize and react to beryllium. While not every beryllium-sensitized person will develop chronic beryllium disease (CBD), beryllium sensitization is essential for development of CBD.
CBD diagnostic center means a medical diagnostic center that has a pulmonologist or pulmonary specialist on staff and on-site facilities to perform a clinical evaluation for the presence of chronic beryllium disease (CBD). The CBD diagnostic center must have the capacity to perform pulmonary function testing (as outlined by the American Thoracic Society criteria), bronchoalveolar lavage (BAL), and transbronchial biopsy. The CBD diagnostic center must also have the capacity to transfer BAL samples to a laboratory for appropriate diagnostic testing within 24 hours. The pulmonologist or pulmonary specialist must be able to interpret the biopsy pathology and the BAL diagnostic test results.
Chronic beryllium disease (CBD) means a chronic granulomatous lung disease caused by inhalation of airborne beryllium by an individual who is beryllium-sensitized.
Competent person means an individual who is capable of identifying existing and foreseeable beryllium hazards in the workplace and who has authorization to take prompt corrective measures to eliminate or minimize them. The competent person must have the knowledge, ability, and authority necessary to fulfill the responsibilities set forth in paragraph (e) of this standard.
Confirmed positive means the person tested has had two abnormal BeLPT test results, an abnormal and a borderline test result, or three borderline test results from tests conducted within a 3-year period. It also means the result of a more reliable and accurate test indicating a person has been identified as having beryllium sensitization.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Objective data means information, such as air monitoring data from industry-wide surveys or calculations based on the composition of a substance, demonstrating airborne exposure to beryllium associated with a particular product or material or a specific process, task, or activity. The data must reflect workplace conditions closely resembling or with a higher airborne exposure potential than the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Physician or other licensed health care professional (PLHCP) means an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows the individual to independently provide or be delegated the responsibility to provide some or all of the health care services required by paragraph (k) of this standard.
This standard means this beryllium standard, 29 CFR 1926.1124.
The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 0.2 µg/m 3 calculated as an 8-hour TWA.
The employer must ensure that no employee is exposed to an airborne concentration of beryllium in excess of 2.0 µg/m 3 as determined over a sampling period of 15 minutes.
The employer must assess the airborne exposure of each employee who is or may reasonably be expected to be exposed to airborne beryllium in accordance with either the performance option in paragraph (d)(2) or the scheduled monitoring option in paragraph (d)(3) of this standard.
The employer must assess the 8-hour TWA exposure and the 15-minute short-term exposure for each employee on the basis of any combination of air monitoring data and objective data sufficient to accurately characterize airborne exposure to beryllium.
The employer must reassess airborne exposure whenever a change in the production, process, control equipment, personnel, or work practices may reasonably be expected to result in new or additional airborne exposure at or above the action level or STEL, or when the employer has any reason to believe that new or additional airborne exposure at or above the action level or STEL has occurred.
The employer must ensure that all air monitoring samples used to satisfy the monitoring requirements of paragraph (d) of this standard are evaluated by a laboratory that can measure beryllium to an accuracy of plus or minus 25 percent within a statistical confidence level of 95 percent for airborne concentrations at or above the action level.
Wherever employees are, or can reasonably be expected to be, exposed to airborne beryllium at levels above the TWA PEL or STEL, the employer must designate a competent person to
The employer must use engineering and work practice controls to reduce and maintain employee airborne exposure to beryllium to or below the TWA PEL and STEL, unless the employer can demonstrate that such controls are not feasible. Wherever the employer demonstrates that it is not feasible to reduce airborne exposure to or below the PELs with engineering and work practice controls, the employer must implement and maintain engineering and work practice controls to reduce airborne exposure to the lowest levels feasible and supplement these controls by using respiratory protection in accordance with paragraph (g) of this standard.
The employer must not rotate employees to different jobs to achieve compliance with the PELs.
The employer must provide respiratory protection at no cost to the employee and ensure that each employee uses respiratory protection:
Where this standard requires an employer to provide respiratory protection, the selection and use of such respiratory protection must be in accordance with the Respiratory Protection standard (29 CFR 1910.134).
Where airborne exposure exceeds, or can reasonably be expected to exceed, the TWA PEL or STEL, the employer must provide at no cost, and ensure that each employee uses, appropriate personal protective clothing and equipment in accordance with the written exposure control plan required under paragraph (f)(1) of this standard and OSHA's Personal Protective and Life Saving Equipment standards for construction (subpart E of this part).
The employer must provide a medical examination:
The employer must ensure that the examining PLHCP (and the agreed-upon CBD diagnostic center, if an evaluation is required under paragraph (k)(7) of this standard) has a copy of this standard and must provide the following information, if known:
The employer must ensure that the employee receives a written medical report from the licensed physician within 45 days of the examination (including any follow-up BeLPT required under paragraph (k)(3)(ii)(E) of this standard) and that the PLHCP explains the results of the examination to the employee. The written medical report must contain:
Upon request, the employer must make all records maintained as a requirement of this standard available for examination and copying to the Assistant Secretary, the Director, each employee, and each employee's designated representative(s) in accordance the Records Access standard (29 CFR 1910.1020).
The employer must comply with the requirements involving transfer of records set forth in the Records Access standard (29 CFR 1910.1020).
This standard shall become effective March 10, 2017.
[82 FR 2751, Jan. 9, 2017, as amended at 84 FR 51400, Sept. 30, 2019; 85 FR 53997, Aug. 31, 2020; 86 FR 11120, Feb. 24, 2021]
For the purposes of this section the following definitions apply:
Action level means a concentration of airborne chromium (VI) of 2.5 micrograms per cubic meter of air (2.5 µgm/m 3 ) calculated as an 8-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Chromium (VI) [hexavalent chromium or Cr(VI)] means chromium with a valence of positive six, in any form and in any compound.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Emergency means any occurrence that results, or is likely to result, in an uncontrolled release of chromium (VI). If an incidental release of chromium (VI) can be controlled at the time of release by employees in the immediate release area, or by maintenance personnel, it is not an emergency.
Employee exposure means the exposure to airborne chromium (VI) that would occur if the employee were not using a respirator.
High-efficiency particulate air [HEPA] filter means a filter that is at least 99.97 percent efficient in removing mono-dispersed particles of 0.3 micrometers in diameter or larger.
Historical monitoring data means data from chromium (VI) monitoring conducted prior to May 30, 2006, obtained during work operations conducted under workplace conditions closely resembling the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Objective data means information such as air monitoring data from industry-wide surveys or calculations based on the composition or chemical and physical properties of a substance demonstrating the employee exposure to chromium (VI) associated with a particular product or material or a specific process, operation, or activity. The data must reflect workplace conditions closely resembling the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Physician or other licensed health care professional [PLHCP] is an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required by paragraph (i) of this section.
This section means this § 1926.1126 chromium (VI) standard.
The employer shall ensure that no employee is exposed to an airborne concentration of chromium (VI) in excess of 5 micrograms per cubic meter of air (5 µgm/m 3 ), calculated as an 8-hour time-weighted average (TWA).
Each employer who has a workplace or work operation covered by this section shall determine the 8-hour TWA exposure for each employee exposed to chromium (VI). This determination shall be made in accordance with either paragraph (d)(2) or paragraph (d)(3) of this section.
The employer shall determine the 8-hour TWA exposure for each employee on the basis of any combination of air monitoring data, historical monitoring data, or objective data sufficient to accurately characterize employee exposure to chromium (VI).
Where air monitoring is performed to comply with the requirements of this section, the employer shall use a method of monitoring and analysis that can measure chromium (VI) to within an accuracy of plus or minus 25 percent (±25%) and can produce accurate measurements to within a statistical confidence level of 95 percent for airborne concentrations at or above the action level.
The employer shall not rotate employees to different jobs to achieve compliance with the PEL.
Where respiratory protection is required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respiratory protection is required during:
Where respirator use is required by this section, the employer shall institute a respiratory protection program in accordance with § 1910.134, which covers each employee required to use a respirator.
Where a hazard is present or is likely to be present from skin or eye contact with chromium (VI), the employer shall provide appropriate personal protective clothing and equipment at no cost to employees, and shall ensure that employees use such clothing and equipment.
Where protective clothing and equipment is required, the employer shall provide change rooms in conformance with 29 CFR 1926.51 Where skin contact with chromium (VI) occurs, the employer shall provide washing facilities in conformance with 29 CFR 1926.51. Eating and drinking areas provided by the employer shall also be in conformance with § 1926.51.
The employer shall assure that change rooms are equipped with separate storage facilities for protective clothing and equipment and for street clothes, and that these facilities prevent cross-contamination.
The employer shall ensure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in areas where skin or eye contact with chromium (VI) occurs; or carry the products associated with these activities, or store such products in these areas.
The employer shall provide a medical examination:
A medical examination consists of:
The employer shall ensure that the examining PLHCP has a copy of this standard, and shall provide the following information:
The employer shall include chromium (VI) in the program established to comply with the Hazard Communication Standard (HCS) (§ 1910.1200). The employer shall ensure that each employee has access to labels on containers of chromium and safety data sheets, and is trained in accordance with the provisions of § 1910.1200 and paragraph (j)(2) of this section. The employer shall provide information on at least the following hazards: Cancer; eye irritation; and skin sensitization.
[71 FR 10382, Feb. 28, 2006, as amended at 73 FR 75589, Dec. 12, 2008; 75 FR 12686, Mar. 17, 2010; 77 FR 17895, Mar. 26, 2012]
This standard applies to all occupational exposures to cadmium and cadmium compounds, in all forms, in all construction work where an employee may potentially be exposed to cadmium. Construction work is defined as work involving construction, alteration and/or repair, including but not limited to the following:
Action level (AL) is defined as an airborne concentration of cadmium of 2.5 micrograms per cubic meter of air (2.5 µg/m 3 ), calculated as an 8-hour time-weighted average (TWA).
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Authorized person means any person authorized by the employer and required by work duties to be present in regulated areas or any person authorized by the OSH Act or regulations issued under it to be in regulated areas.
Competent person, in accordance with 29 CFR 1926.32(f), means a person designated by the employer to act on the employer's behalf who is capable of identifying existing and potential cadmium hazards in the workplace and the proper methods to control them in order to protect workers, and has the authority necessary to take prompt corrective measures to eliminate or control such hazards. The duties of a competent person include at least the following: Determining prior to the performance of work whether cadmium is present in the workplace; establishing, where necessary, regulated areas and assuring that access to and from those areas is limited to authorized employees; assuring the adequacy of any employee exposure monitoring required by this standard; assuring that all employees exposed to air cadmium levels above the PEL wear appropriate personal protective equipment and are trained in the use of appropriate methods of exposure control; assuring that proper hygiene facilities are provided and that workers are trained to use those facilities; and assuring that the engineering controls required by this standard are implemented, maintained in proper operating condition, and functioning properly.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Employee exposure and similar language referring to the air cadmium level to which an employee is exposed means the exposure to airborne cadmium that would occur if the employee were not using respiratory protective equipment.
Final medical determination is the written medical opinion of the employee's health status by the examining physician under paragraphs (l)(3)-
High-efficiency Particulate Air [HEPA] filter means a filter capable of trapping and retaining at least 99.97 percent of mono-dispersed particles of 0.3 micrometers in diameter.
Regulated area means an area demarcated by the employer where an employee's exposure to airborne concentrations of cadmium exceeds, or can reasonably be expected to exceed the permissible exposure limit (PEL).
This section means this cadmium standard.
The employer shall assure that no employee is exposed to an airborne concentration of cadmium in excess of five micrograms per cubic meter of air (5 µg/m 3 ), calculated as an eight-hour time-weighted average exposure (TWA).
Except as provided for in paragraph (d)(2)(iii) of this section, where a determination conducted under paragraph (d)(1)(i) of this section shows the possibility of employee exposure to cadmium at or above the action level, the employer shall conduct exposure monitoring as soon as practicable that is representative of the exposure for each employee in the workplace who is or may be exposed to cadmium at or above the action level.
The employer also shall institute the exposure monitoring required under paragraphs (d)(2)(i) and (d)(3) of this section whenever there has been a change in the raw materials, equipment, personnel, work practices, or finished products that may result in additional employees being exposed to cadmium at or above the action level or in employees already exposed to cadmium at or above the action level being exposed above the PEL, or whenever the employer or competent person has any reason to suspect that any other change might result in such further exposure.
The employer shall use a method of monitoring and analysis that has an accuracy of not less than plus or minus 25 percent (±25%), with a confidence level of 95 percent, for airborne concentrations of cadmium at or above the action level and the permissible exposure limit.
The employer shall establish a regulated area wherever an employee's exposure to airborne concentrations of cadmium is, or can reasonably be expected to be in excess of the permissible exposure limit (PEL).
Regulated areas shall be demarcated from the rest of the workplace in any manner that adequately establishes and alerts employees of the boundaries of the regulated area, including employees who are or may be incidentally in the regulated areas, and that protects persons outside the area from exposure to airborne concentrations of cadmium in excess of the PEL.
Access to regulated areas shall be limited to authorized persons.
Each person entering a regulated area shall be supplied with and required to use a respirator, selected in accordance with paragraph (g)(2) of this section.
The employer shall assure that employees do not eat, drink, smoke, chew tobacco or gum, or apply cosmetics in regulated areas, or carry the products associated with any of these activities into regulated areas or store such products in those areas.
Abrasive blasting on cadmium or cadmium-containing materials shall be conducted in a manner that will provide adequate protection.
Welding, cutting, and other forms of heating of cadmium or cadmium-containing materials shall be conducted in accordance with the requirements of 29 CFR 1926.353 and 29 CFR 1926.354, where applicable.
If air from exhaust ventilation is recirculated into the workplace, the system shall have a high efficiency filter and be monitored to assure effectiveness.
For employees who use respirators required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph. Respirators must be used during:
The employer shall develop and implement a written plan for dealing with emergency situations involving substantial releases of airborne cadmium. The plan shall include provisions for the use of appropriate respirators and personal protective equipment. In addition, employees not essential to correcting the emergency situation shall be restricted from the area and normal operations halted in that area until the emergency is abated.
If an employee is exposed to airborne cadmium above the PEL or where skin or eye irritation is associated with cadmium exposure at any level, the employer shall provide at no cost to the employee, and assure that the employee uses, appropriate protective work clothing and equipment that prevents contamination of the employee and the employee's garments. Protective work clothing and equipment includes, but is not limited to:
For employees whose airborne exposure to cadmium is above the PEL, the employer shall provide clean change rooms, handwashing facilities, showers, and lunchroom facilities that comply with 29 CFR 1926.51.
The employer shall assure that change rooms are equipped with separate storage facilities for street clothes and for protective clothing and equipment, which are designed to prevent dispersion of cadmium and contamination of the employee's street clothes.
The employer shall also institute a medical surveillance program for all employees who might previously have been exposed to cadmium by the employer prior to the effective date of this standard in tasks specified under paragraph (l)(1)(i)(A) of this section, unless the employer demonstrates that the employee did not in the years prior to the effective date of this section work in those tasks for the employer with exposure to cadmium for an aggregated total of more than 12 months.
An initial examination is not required to be provided if adequate records show that the employee has been examined in accordance with the requirements of paragraph (l)(2)(ii) of this section within the past 12 months. In that case, such records shall be maintained as part of the employee's medical record and the prior exam shall be treated as if it were an initial examination for the purposes of paragraphs (l)(3) and (4) of this section.
Within 90 days after receipt of biological monitoring results, the employer shall provide a full medical examination to the employee in accordance with the requirements of paragraph (l)(4)(ii) of this section. After completing the medical examination, the examining physician shall determine in a written medical opinion whether to medically remove the employee. However, if the initial biological monitoring results and the biological monitoring results obtained during the medical examination both show that: CdU exceeds 15 µg/g Cr; or CdB exceeds 15 µg/lwb; or β 2 -M exceeds 1500 µg/g Cr, and in addition CdU exceeds 3 µg/g Cr or CdB exceeds 5 µg/liter of whole blood, then the physician shall medically remove the employee from exposure to cadmium at or above the action level. If the second set of biological monitoring results obtained during the medical examination does not show that a mandatory removal trigger level has been exceeded, then the employee is not required to be removed by the mandatory provisions of this paragraph. If the employee is not required to be removed by the mandatory provisions of this paragraph or by the physician's determination, then until the employee's CdU level falls to or below 3 µg/g Cr, β 2 -M level falls to or below 300 µg/g Cr and CdB level falls to or below 5 µg/lwb, the employer shall:
Within 90 days after receipt of biological monitoring results, the employer shall provide a full medical examination to the employee in accordance with the requirements of paragraph (l)(4)(ii) of this section. After completing the medical examination, the examining physician shall determine in a written medical opinion whether to medically remove the employee. However, if the initial biological monitoring results and the biological monitoring results obtained during the medical examination both show that: CdU exceeds 7 µg/g Cr; or CdB exceeds 10 µg/lwb; or β 2 -M exceeds 750 µg/g Cr, and in addition CdU exceeds 3 µg/g Cr or CdB exceeds 5 µg/liter of whole blood, then the physician shall medically remove the employee from exposure to cadmium at or above the action level. If the second set of biological monitoring results obtained during the medical examination does not show that a mandatory removal trigger level has been exceeded, then the employee is not required to be removed by the mandatory provisions of this paragraph. If the employee is not required to be removed by the mandatory provisions of this paragraph or by the physician's determination, then until the employee's CdU level falls to or below 3 µg/g Cr, β 2 -M level falls to or below 300 µg/g Cr and CdB level falls to or below 5 µg/lwb, the employer shall:
blood pressure, the respiratory system, and the urinary system;
inch by 17 inch or other reasonably-sized standard film or digital posterior-anterior chest X-ray (after the initial X-ray, the frequency of chest X-rays is to be determined by the examining physician);
The employee's work practices and personal hygiene; the employee's respirator use, if any; the employee's smoking history and status; the respiratory protection program; the hygiene facilities; the maintenance and effectiveness of the relevant engineering controls; and take all reasonable steps to correct the deficiencies found in the reassessment that may be responsible for the employee's excess exposure to cadmium.
This examination shall be provided prior to the employee's being assigned to a job that requires the use of a respirator or no later than 90 days after this section goes into effect, whichever date is later, to any employee without a medical examination within the preceding 12 months that satisfies the requirements of this paragraph.
The employer shall provide the following information to the examining physician:
The employer and an employee or designated employee representative may agree upon the use of any alternate form of physician determination in lieu of the multiple physician review provided by paragraph (l)(13) of this section, so long as the alternative is expeditious and at least as protective of the employee.
In addition to other medical events that are required to be reported on the OSHA Form No. 200, the employer shall report any abnormal condition or disorder caused by occupational exposure to cadmium associated with employment as specified in Chapter (V)(E) of the Reporting Guidelines for Occupational Injuries and Illnesses.
The employer shall include cadmium in the program established to comply with the Hazard Communication Standard (HCS) (§ 1910.1200). The employer shall ensure that each employee has access to labels on containers of cadmium and safety data sheets, and is trained in accordance with the provisions of HCS and paragraph (m)(4) of this section. The employer shall provide information on at least the following hazards: Cancer; lung effects; kidney effects; and acute toxicity effects.
DANGER
CADMIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS AND KIDNEYS
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY
DANGER
CADMIUM
CANCER HAZARD
CAN CAUSE LUNG AND KIDNEY DISEASE
AUTHORIZED PERSONNEL ONLY
RESPIRATORS REQUIRED IN THIS AREA
DANGER
CONTAINS CADMIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS AND KIDNEYS
AVOID CREATING DUST
DANGER
CONTAINS CADMIUM
CANCER HAZARD
AVOID CREATING DUST
CAN CAUSE LUNG AND KIDNEY DISEASE
In a multi-employer workplace, an employer who produces, uses, or stores cadmium in a manner that may expose employees of other employers to cadmium shall notify those employers of the potential hazard in accordance with paragraph (e) of the hazard communication standard for construction, 29 CFR 1926.59.
The employer shall provide affected employees or their designated representatives an opportunity to observe any monitoring of employee exposure to cadmium.
When observation of monitoring requires entry into an area where the use of protective clothing or equipment is required, the employer shall provide the observer with that clothing and equipment and shall assure that the observer uses such clothing and equipment and complies with all other applicable safety and health procedures.
Except where portions of appendices A, B, D, E, and F to this section are expressly incorporated in requirements of this section, these appendices are purely informational and are not intended to create any additional obligations not otherwise imposed or to detract from any existing obligations.
Appendix A to § 1926.1127—Substance Safety Data Sheet
Appendix B to § 1926.1127—Substance Technical Guidelines for Cadmium
Appendix D to § 1926.1127—Occupational Health History Interview With Reference to Cadmium Exposure
Appendix E to § 1926.1127—Cadmium in Workplace Atmospheres
Appendix F to § 1926.1127—Nonmandatory Protocol for Biological Monitoring
[57 FR 42452, Sept. 14, 1992, as amended at 57 FR 49272, Oct. 30, 1992; 58 FR 21787, Apr. 23, 1993. Redesignated and amended at 59 FR 215, Jan. 3, 1994; 61 FR 5510, Feb. 13, 1996; 61 FR 31433, 31434, June 20, 1996; 63 FR 1298, Jan. 8, 1998; 70 FR 1144, Jan. 5, 2005; 71 FR 16675, Apr. 3, 2006; 71 FR 50192, Aug. 24, 2006; 73 FR 75589, Dec. 12, 2008; 76 FR 33612, June 8, 2011; 77 FR 17895, Mar. 26, 2012; 84 FR 21597, May 14, 2019; 85 FR 8746, Feb. 18, 2020]
[61 FR 31434, June 20, 1996]
[61 FR 31434, June 20, 1996]
[61 FR 31434, June 20, 1996]
[61 FR 31434, June 20, 1996]
[61 FR 31434, June 20, 1996]
[62 FR 1619, Jan. 10, 1997]
This section applies to all occupational exposures to respirable crystalline silica in construction work, except where employee exposure will remain below 25 micrograms per cubic meter of air (25 µg/m 3 ) as an 8-hour time-weighted average (TWA) under any foreseeable conditions.
For the purposes of this section the following definitions apply:
Action level means a concentration of airborne respirable crystalline silica of 25 µg/m 3, calculated as an 8-hour TWA.
Assistant Secretary means the Assistant Secretary of Labor for Occupational Safety and Health, U.S. Department of Labor, or designee.
Director means the Director of the National Institute for Occupational Safety and Health (NIOSH), U.S. Department of Health and Human Services, or designee.
Competent person means an individual who is capable of identifying existing and foreseeable respirable crystalline silica hazards in the workplace and who has authorization to take prompt corrective measures to eliminate or minimize them. The competent person must have the knowledge and ability necessary to fulfill the responsibilities set forth in paragraph (g) of this section.
Employee exposure means the exposure to airborne respirable crystalline silica that would occur if the employee were not using a respirator.
High-efficiency particulate air [HEPA] filter means a filter that is at least 99.97 percent efficient in removing mono-dispersed particles of 0.3 micrometers in diameter.
Objective data means information, such as air monitoring data from industry-wide surveys or calculations based on the composition of a substance, demonstrating employee exposure to respirable crystalline silica associated with a particular product or material or a specific process, task, or activity. The data must reflect workplace conditions closely resembling or with a higher exposure potential than the processes, types of material, control methods, work practices, and environmental conditions in the employer's current operations.
Physician or other licensed health care professional [PLHCP] means an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required by paragraph (h) of this section.
Respirable crystalline silica means quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirable-particle-size-selective samplers specified in the International Organization for Standardization (ISO) 7708:1995: Air Quality—Particle Size Fraction Definitions for Health-Related Sampling.
Specialist means an American Board Certified Specialist in Pulmonary Disease or an American Board Certified Specialist in Occupational Medicine.
This section means this respirable crystalline silica standard, 29 CFR 1926.1153.
| Equipment/task | Engineering and work practice control methods | Required respiratory protection and minimum assigned protection factor (APF) | |
|---|---|---|---|
| ≤4 hours/shift | >4 hours/shift | ||
| (i) Stationary masonry saws | Use saw equipped with integrated water delivery system that continuously feeds water to the blade | None | None. |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| (ii) Handheld power saws (any blade diameter) | Use saw equipped with integrated water delivery system that continuously feeds water to the blade | ||
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions: | |||
| —When used outdoors | None | APF 10. | |
| —When used indoors or in an enclosed area | APF 10 | APF 10. | |
| (iii) Handheld power saws for cutting fiber-cement board (with blade diameter of 8 inches or less) | For tasks performed outdoors only: Use saw equipped with commercially available dust collection system Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | None | None. |
| Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency | |||
| (iv) Walk-behind saws | Use saw equipped with integrated water delivery system that continuously feeds water to the blade | ||
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions: | |||
| —When used outdoors | None | None. | |
| —When used indoors or in an enclosed area | APF 10 | APF 10. | |
| (v) Drivable saws | For tasks performed outdoors only: | ||
| Use saw equipped with integrated water delivery system that continuously feeds water to the blade | None | None. | |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| (vi) Rig-mounted core saws or drills | Use tool equipped with integrated water delivery system that supplies water to cutting surface | None | None. |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| (vii) Handheld and stand-mounted drills (including impact and rotary hammer drills) | Use drill equipped with commercially available shroud or cowling with dust collection system | None | None. |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism | |||
| Use a HEPA-filtered vacuum when cleaning holes | |||
| (viii) Dowel drilling rigs for concrete | For tasks performed outdoors only: | ||
| Use shroud around drill bit with a dust collection system. Dust collector must have a filter with 99% or greater efficiency and a filter-cleaning mechanism | APF 10 | APF 10. | |
| Use a HEPA-filtered vacuum when cleaning holes | |||
| (ix) Vehicle-mounted drilling rigs for rock and concrete | Use dust collection system with close capture hood or shroud around drill bit with a low-flow water spray to wet the dust at the discharge point from the dust collector | None | None. |
| OR | |||
| Operate from within an enclosed cab and use water for dust suppression on drill bit | None | None. | |
| (x) Jackhammers and handheld powered chipping tools | Use tool with water delivery system that supplies a continuous stream or spray of water at the point of impact: | ||
| —When used outdoors | None | APF 10. | |
| —When used indoors or in an enclosed area | APF 10 | APF 10. | |
| OR | |||
| Use tool equipped with commercially available shroud and dust collection system | |||
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| Dust collector must provide the air flow recommended by the tool manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism: | |||
| —When used outdoors | None | APF 10. | |
| —When used indoors or in an enclosed area | APF 10 | APF 10. | |
| (xi) Handheld grinders for mortar removal ( i.e. , tuckpointing) | Use grinder equipped with commercially available shroud and dust collection system | APF 10 | APF 25. |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| Dust collector must provide 25 cubic feet per minute (cfm) or greater of airflow per inch of wheel diameter and have a filter with 99% or greater efficiency and a cyclonic pre-separator or filter-cleaning mechanism | |||
| (xii) Handheld grinders for uses other than mortar removal | For tasks performed outdoors only: Use grinder equipped with integrated water delivery system that continuously feeds water to the grinding surface | None | None. |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| OR | |||
| Use grinder equipped with commercially available shroud and dust collection system | |||
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| Dust collector must provide 25 cubic feet per minute (cfm) or greater of airflow per inch of wheel diameter and have a filter with 99% or greater efficiency and a cyclonic pre-separator or filter-cleaning mechanism: | |||
| —When used outdoors | None | None. | |
| —When used indoors or in an enclosed area | None | APF 10. | |
| (xiii) Walk-behind milling machines and floor grinders | Use machine equipped with integrated water delivery system that continuously feeds water to the cutting surface | None | None. |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| OR | |||
| Use machine equipped with dust collection system recommended by the manufacturer | None | None. | |
| Operate and maintain tool in accordance with manufacturer's instructions to minimize dust emissions | |||
| Dust collector must provide the air flow recommended by the manufacturer, or greater, and have a filter with 99% or greater efficiency and a filter-cleaning mechanism | |||
| When used indoors or in an enclosed area, use a HEPA-filtered vacuum to remove loose dust in between passes | |||
| (xiv) Small drivable milling machines (less than half-lane) | Use a machine equipped with supplemental water sprays designed to suppress dust. Water must be combined with a surfactant | None | None. |
| Operate and maintain machine to minimize dust emissions | |||
| (xv) Large drivable milling machines (half-lane and larger) | For cuts of any depth on asphalt only: Use machine equipped with exhaust ventilation on drum enclosure and supplemental water sprays designed to suppress dust | None | None. |
| Operate and maintain machine to minimize dust emissions | |||
| For cuts of four inches in depth or less on any substrate: | |||
| Use machine equipped with exhaust ventilation on drum enclosure and supplemental water sprays designed to suppress dust | None | None. | |
| Operate and maintain machine to minimize dust emissions | |||
| OR | |||
| Use a machine equipped with supplemental water spray designed to suppress dust. Water must be combined with a surfactant | None | None. | |
| Operate and maintain machine to minimize dust emissions | |||
| (xvi) Crushing machines | Use equipment designed to deliver water spray or mist for dust suppression at crusher and other points where dust is generated ( e.g. , hoppers, conveyers, sieves/sizing or vibrating components, and discharge points) | None | None. |
| Operate and maintain machine in accordance with manufacturer's instructions to minimize dust emissions | |||
| Use a ventilated booth that provides fresh, climate-controlled air to the operator, or a remote control station | |||
| (xvii) Heavy equipment and utility vehicles used to abrade or fracture silica-containing materials ( e.g. , hoe-ramming, rock ripping) or used during demolition activities involving silica-containing materials | Operate equipment from within an enclosed cab When employees outside of the cab are engaged in the task, apply water and/or dust suppressants as necessary to minimize dust emissions | None None | None. None. |
| (xviii) Heavy equipment and utility vehicles for tasks such as grading and excavating but not including: Demolishing, abrading, or fracturing silica-containing materials | Apply water and/or dust suppressants as necessary to minimize dust emissions OR | None | None. |
| When the equipment operator is the only employee engaged in the task, operate equipment from within an enclosed cab | None | None. |
For tasks not listed in Table 1, or where the employer does not fully and properly implement the engineering controls, work practices, and respiratory protection described in Table 1:
The employer shall ensure that no employee is exposed to an airborne concentration of respirable crystalline silica in excess of 50 µg/m 3, calculated as an 8-hour TWA.
The employer shall assess the exposure of each employee who is or may reasonably be expected to be exposed to respirable crystalline silica at or above the action level in accordance with either the performance option in paragraph (d)(2)(ii) or the scheduled monitoring option in paragraph (d)(2)(iii) of this section.
The employer shall assess the 8-hour TWA exposure for each employee on the basis of any combination of air monitoring data or objective data sufficient to accurately characterize employee exposures to respirable crystalline silica.
The employer shall reassess exposures whenever a change in the production, process, control equipment, personnel, or work practices may reasonably be expected to result in new or additional exposures at or above the action level, or when the employer has any reason to believe that new or additional exposures at or above the action level have occurred.
The employer shall ensure that all samples taken to satisfy the monitoring requirements of paragraph (d)(2) of this section are evaluated by a laboratory that analyzes air samples for respirable crystalline silica in accordance with the procedures in appendix A to this section.
The employer shall use engineering and work practice controls to reduce and maintain employee exposure to respirable crystalline silica to or below the PEL, unless the employer can demonstrate that such controls are not feasible. Wherever such feasible engineering and work practice controls are not sufficient to reduce employee exposure to or below the PEL, the employer shall nonetheless use them to reduce employee exposure to the lowest feasible level and shall supplement them with the use of respiratory protection that complies with the requirements of paragraph (e) of this section.
In addition to the requirements of paragraph (d)(3)(i) of this section, the employer shall comply with other OSHA standards, when applicable, such as 29 CFR 1926.57 (Ventilation), where abrasive blasting is conducted using crystalline silica-containing blasting agents, or where abrasive blasting is conducted on substrates that contain crystalline silica.
Where respiratory protection is required by this section, the employer must provide each employee an appropriate respirator that complies with the requirements of this paragraph and 29 CFR 1910.134. Respiratory protection is required:
Where respirator use is required by this section, the employer shall institute a respiratory protection program in accordance with 29 CFR 1910.134.
For the tasks listed in Table 1 in paragraph (c) of this section, if the employer fully and properly implements the engineering controls, work practices, and respiratory protection described in Table 1, the employer shall be considered to be in compliance with paragraph (e)(1) of this section and the requirements for selection of respirators in 29 CFR 1910.134(d)(1)(iii) and (d)(3) with regard to exposure to respirable crystalline silica.
The employer shall make available an initial (baseline) medical examination within 30 days after initial assignment, unless the employee has received a medical examination that meets the requirements of this section within the last three years. The examination shall consist of:
The employer shall make available medical examinations that include the procedures described in paragraph (h)(2) of this section (except paragraph (h)(2)(v)) at least every three years, or more frequently if recommended by the PLHCP.
The employer shall ensure that the examining PLHCP has a copy of this standard, and shall provide the PLHCP with the following information:
The employer shall ensure that the PLHCP explains to the employee the results of the medical examination and provides each employee with a written medical report within 30 days of each medical examination performed. The written report shall contain:
The employer shall include respirable crystalline silica in the program established to comply with the hazard communication standard (HCS) (29 CFR 1910.1200). The employer shall ensure that each employee has access to labels on containers of crystalline silica and safety data sheets, and is trained in accordance with the provisions of HCS and paragraph (i)(2) of this section. The employer shall ensure that at least the following hazards are addressed: Cancer, lung effects, immune system effects, and kidney effects.
Appendix A to § 1926.1153—Methods of Sample Analysis
This This appendix specifies the procedures for analyzing air samples for respirable crystalline silica, as well as the quality control procedures that employers must ensure that laboratories use when performing an analysis required under 29 CFR 1926.1153 (d)(2)(v). Employers must ensure that such a laboratory:
1. Evaluates all samples using the procedures specified in one of the following analytical methods: OSHA ID-142; NMAM 7500; NMAM 7602; NMAM 7603; MSHA P-2; or MSHA P-7;
2. Is accredited to ANS/ISO/IEC Standard 17025:2005 with respect to crystalline silica analyses by a body that is compliant with ISO/IEC Standard 17011:2004 for implementation of quality assessment programs;
3. Uses the most current National Institute of Standards and Technology (NIST) or NIST traceable standards for instrument calibration or instrument calibration verification;
4. Implements an internal quality control (QC) program that evaluates analytical uncertainty and provides employers with estimates of sampling and analytical error;
5. Characterizes the sample material by identifying polymorphs of respirable crystalline silica present, identifies the presence of any interfering compounds that might affect the analysis, and makes any corrections necessary in order to obtain accurate sample analysis; and
6. Analyzes quantitatively for crystalline silica only after confirming that the sample matrix is free of uncorrectable analytical interferences, corrects for analytical interferences, and uses a method that meets the following performance specifications:
6.1 Each day that samples are analyzed, performs instrument calibration checks with standards that bracket the sample concentrations;
6.2 Uses five or more calibration standard levels to prepare calibration curves and ensures that standards are distributed through the calibration range in a manner that accurately reflects the underlying calibration curve; and
6.3 Optimizes methods and instruments to obtain a quantitative limit of detection that represents a value no higher than 25 percent of the PEL based on sample air volume.
Appendix B to § 1926.1153—Medical Surveillance Guidelines
Introduction
The purpose of this Appendix is to provide medical information and recommendations to aid physicians and other licensed health care professionals (PLHCPs) regarding compliance with the medical surveillance provisions of the respirable crystalline silica standard (29 CFR 1926.1153). Appendix B is for informational and guidance purposes only and none of the statements in Appendix B should be construed as imposing a mandatory requirement on employers that is not otherwise imposed by the standard.
Medical screening and surveillance allow for early identification of exposure-related health effects in individual employee and groups of employees, so that actions can be taken to both avoid further exposure and prevent or address adverse health outcomes. Silica-related diseases can be fatal, encompass a variety of target organs, and may have public health consequences when considering the increased risk of a latent tuberculosis (TB) infection becoming active. Thus, medical surveillance of silica-exposed employees requires that PLHCPs have a thorough knowledge of silica-related health effects.
This Appendix is divided into seven sections. Section 1 reviews silica-related diseases, medical responses, and public health responses. Section 2 outlines the components of the medical surveillance program for employees exposed to silica. Section 3 describes the roles and responsibilities of the PLHCP implementing the program and of other medical specialists and public health professionals. Section 4 provides a discussion of considerations, including confidentiality. Section 5 provides a list of additional resources and Section 6 lists references. Section 7 provides sample forms for the written medical report for the employee, the written medical opinion for the employer and the written authorization.
1. Recognition of Silica-Related Diseases
1.1. Overview. The term “silica” refers specifically to the compound silicon dioxide (SiO 2 ). Silica is a major component of sand, rock, and mineral ores. Exposure to fine (respirable size) particles of crystalline forms of silica is associated with adverse health effects, such as silicosis, lung cancer, chronic obstructive pulmonary disease (COPD), and activation of latent TB infections. Exposure to respirable crystalline silica can occur in industry settings such as foundries, abrasive blasting operations, paint manufacturing, glass and concrete product manufacturing, brick making, china and pottery manufacturing, manufacturing of plumbing fixtures, and many construction activities including highway repair, masonry, concrete work, rock drilling, and tuck-pointing. New uses of silica continue to emerge. These include countertop manufacturing, finishing, and installation (Kramer et al. 2012; OSHA 2015) and hydraulic fracturing in the oil and gas industry (OSHA 2012).
Silicosis is an irreversible, often disabling, and sometimes fatal fibrotic lung disease. Progression of silicosis can occur despite removal from further exposure. Diagnosis of silicosis requires a history of exposure to silica and radiologic findings characteristic of silica exposure. Three different presentations of silicosis (chronic, accelerated, and acute) have been defined. Accelerated and acute silicosis are much less common than chronic silicosis. However, it is critical to recognize all cases of accelerated and acute silicosis because these are life-threatening illnesses and because they are caused by substantial overexposures to respirable crystalline silica. Although any case of silicosis indicates a breakdown in prevention, a case of acute or accelerated silicosis implies current high exposure and a very marked breakdown in prevention.
In addition to silicosis, employees exposed to respirable crystalline silica, especially those with accelerated or acute silicosis, are at increased risks of contracting active TB and other infections (ATS 1997; Rees and Murray 2007). Exposure to respirable crystalline silica also increases an employee's risk of developing lung cancer, and the higher the cumulative exposure, the higher the risk (Steenland et al. 2001; Steenland and Ward 2014). Symptoms for these diseases and other respirable crystalline silica-related diseases are discussed below.
1.2. Chronic Silicosis. Chronic silicosis is the most common presentation of silicosis and usually occurs after at least 10 years of exposure to respirable crystalline silica. The clinical presentation of chronic silicosis is:
1.2.1. Symptoms—shortness of breath and cough, although employees may not notice any symptoms early in the disease. Constitutional symptoms, such as fever, loss of appetite and fatigue, may indicate other diseases associated with silica exposure, such as TB infection or lung cancer. Employees with these symptoms should immediately receive further evaluation and treatment.
1.2.2. Physical Examination—may be normal or disclose dry rales or rhonchi on lung auscultation.
1.2.3. Spirometry—may be normal or may show only a mild restrictive or obstructive pattern.
1.2.4. Chest X-ray—classic findings are small, rounded opacities in the upper lung fields bilaterally. However, small irregular opacities and opacities in other lung areas can also occur. Rarely, “eggshell calcifications” in the hilar and mediastinal lymph nodes are seen.
1.2.5. Clinical Course—chronic silicosis in most cases is a slowly progressive disease. Under the respirable crystalline silica standard, the PLHCP is to recommend that employees with a 1/0 category X-ray be referred to an American Board Certified Specialist in Pulmonary Disease or Occupational Medicine. The PLHCP and/or Specialist should counsel employees regarding work practices and personal habits that could affect employees' respiratory health.
1.3. Accelerated Silicosis. Accelerated silicosis generally occurs within 5-10 years of exposure and results from high levels of exposure to respirable crystalline silica. The clinical presentation of accelerated silicosis is:
1.3.1. Symptoms—shortness of breath, cough, and sometimes sputum production. Employees with exposure to respirable crystalline silica, and especially those with accelerated silicosis, are at high risk for activation of TB infections, atypical mycobacterial infections, and fungal superinfections. Constitutional symptoms, such as fever, weight loss, hemoptysis (coughing up blood), and fatigue may herald one of these infections or the onset of lung cancer.
1.3.2. Physical Examination—rales, rhonchi, or other abnormal lung findings in relation to illnesses present. Clubbing of the digits, signs of heart failure, and cor pulmonale may be present in severe lung disease.
1.3.3. Spirometry—restrictive or mixed restrictive/obstructive pattern.
1.3.4. Chest X-ray—small rounded and/or irregular opacities bilaterally. Large opacities and lung abscesses may indicate infections, lung cancer, or progression to complicated silicosis, also termed progressive massive fibrosis.
1.3.5. Clinical Course—accelerated silicosis has a rapid, severe course. Under the respirable crystalline silica standard, the PLHCP can recommend referral to a Board Certified Specialist in either Pulmonary Disease or Occupational Medicine, as deemed appropriate, and referral to a Specialist is recommended whenever the diagnosis of accelerated silicosis is being considered.
1.4. Acute Silicosis. Acute silicosis is a rare disease caused by inhalation of extremely high levels of respirable crystalline silica particles. The pathology is similar to alveolar proteinosis with lipoproteinaceous material accumulating in the alveoli. Acute silicosis develops rapidly, often, within a few months to less than 2 years of exposure, and is almost always fatal. The clinical presentation of acute silicosis is as follows:
1.4.1. Symptoms—sudden, progressive, and severe shortness of breath. Constitutional symptoms are frequently present and include fever, weight loss, fatigue, productive cough, hemoptysis (coughing up blood), and pleuritic chest pain.
1.4.2. Physical Examination—dyspnea at rest, cyanosis, decreased breath sounds, inspiratory rales, clubbing of the digits, and fever.
1.4.3. Spirometry—restrictive or mixed restrictive/obstructive pattern.
1.4.4. Chest X-ray—diffuse haziness of the lungs bilaterally early in the disease. As the disease progresses, the “ground glass” appearance of interstitial fibrosis will appear.
1.4.5. Clinical Course—employees with acute silicosis are at especially high risk of TB activation, nontuberculous mycobacterial infections, and fungal superinfections. Acute silicosis is immediately life-threatening. The employee should be urgently referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for evaluation and treatment. Although any case of silicosis indicates a breakdown in prevention, a case of acute or accelerated silicosis implies a profoundly high level of silica exposure and may mean that other employees are currently exposed to dangerous levels of silica.
1.5. COPD. COPD, including chronic bronchitis and emphysema, has been documented in silica-exposed employees, including those who do not develop silicosis. Periodic spirometry tests are performed to evaluate each employee for progressive changes consistent with the development of COPD. In addition to evaluating spirometry results of individual employees over time, PLHCPs may want to be aware of general trends in spirometry results for groups of employees from the same workplace to identify possible problems that might exist at that workplace. ( See Section 2 of this Appendix on Medical Surveillance for further discussion.) Heart disease may develop secondary to lung diseases such as COPD. A recent study by Liu et al. 2014 noted a significant exposure-response trend between cumulative silica exposure and heart disease deaths, primarily due to pulmonary heart disease, such as cor pulmonale.
1.6. Renal and Immune System. Silica exposure has been associated with several types of kidney disease, including glomerulonephritis, nephrotic syndrome, and end stage renal disease requiring dialysis. Silica exposure has also been associated with other autoimmune conditions, including progressive systemic sclerosis, systemic lupus erythematosus, and rheumatoid arthritis. Studies note an association between employees with silicosis and serologic markers for autoimmune diseases, including antinuclear antibodies, rheumatoid factor, and immune complexes (Jalloul and Banks 2007; Shtraichman et al. 2015).
1.7. TB and Other Infections. Silica-exposed employees with latent TB are 3 to 30 times more likely to develop active pulmonary TB infection (ATS 1997; Rees and Murray 2007). Although respirable crystalline silica exposure does not cause TB infection, individuals with latent TB infection are at increased risk for activation of disease if they have higher levels of respirable crystalline silica exposure, greater profusion of radiographic abnormalities, or a diagnosis of silicosis. Demographic characteristics, such as immigration from some countries, are associated with increased rates of latent TB infection. PLHCPs can review the latest Centers for Disease Control and Prevention (CDC) information on TB incidence rates and high risk populations online ( See Section 5 of this Appendix). Additionally, silica-exposed employees are at increased risk for contracting nontuberculous mycobacterial infections, including Mycobacterium avium-intracellulare and Mycobacterium kansaii.
1.8. Lung Cancer. The National Toxicology Program has listed respirable crystalline silica as a known human carcinogen since 2000 (NTP 2014). The International Agency for Research on Cancer (2012) has also classified silica as Group 1 (carcinogenic to humans). Several studies have indicated that the risk of lung cancer from exposure to respirable crystalline silica and smoking is greater than additive (Brown 2009; Liu et al. 2013). Employees should be counseled on smoking cessation.
2. Medical Surveillance
PLHCPs who manage silica medical surveillance programs should have a thorough understanding of the many silica-related diseases and health effects outlined in Section 1 of this Appendix. At each clinical encounter, the PLHCP should consider silica-related health outcomes, with particular vigilance for acute and accelerated silicosis. In this Section, the required components of medical surveillance under the respirable crystalline silica standard are reviewed, along with additional guidance and recommendations for PLHCPs performing medical surveillance examinations for silica-exposed employees.
2.1. History.
2.1.1. The respirable crystalline silica standard requires the following: A medical and work history, with emphasis on: Past, present, and anticipated exposure to respirable crystalline silica, dust, and other agents affecting the respiratory system; any history of respiratory system dysfunction, including signs and symptoms of respiratory disease ( e.g., shortness of breath, cough, wheezing); history of TB; and smoking status and history.
2.1.2. Further, the employer must provide the PLHCP with the following information:
2.1.2.1. A description of the employee's former, current, and anticipated duties as they relate to the employee's occupational exposure to respirable crystalline silica;
2.1.2.2. The employee's former, current, and anticipated levels of occupational exposure to respirable crystalline silica;
2.1.2.3. A description of any personal protective equipment used or to be used by the employee, including when and for how long the employee has used or will use that equipment; and
2.1.2.4. Information from records of employment-related medical examinations previously provided to the employee and currently within the control of the employer.
2.1.3. Additional guidance and recommendations: A history is particularly important both in the initial evaluation and in periodic examinations. Information on past and current medical conditions (particularly a history of kidney disease, cardiac disease, connective tissue disease, and other immune diseases), medications, hospitalizations and surgeries may uncover health risks, such as immune suppression, that could put an employee at increased health risk from exposure to silica. This information is important when counseling the employee on risks and safe work practices related to silica exposure.
2.2. Physical Examination.
2.2.1. The respirable crystalline silica standard requires the following: A physical examination, with special emphasis on the respiratory system. The physical examination must be performed at the initial examination and every three years thereafter.
2.2.2. Additional guidance and recommendations: Elements of the physical examination that can assist the PHLCP include: An examination of the cardiac system, an extremity examination (for clubbing, cyanosis, edema, or joint abnormalities), and an examination of other pertinent organ systems identified during the history.
2.3. TB Testing.
2.3.1. The respirable crystalline silica standard requires the following: Baseline testing for TB on initial examination.
2.3.2. Additional guidance and recommendations:
2.3.2.1. Current CDC guidelines ( See Section 5 of this Appendix) should be followed for the application and interpretation of Tuberculin skin tests (TST). The interpretation and documentation of TST reactions should be performed within 48 to 72 hours of administration by trained PLHCPs.
2.3.2.2. PLHCPs may use alternative TB tests, such as interferon-γ release assays (IGRAs), if sensitivity and specificity are comparable to TST (Mazurek et al. 2010; Slater et al. 2013). PLHCPs can consult the current CDC guidelines for acceptable tests for latent TB infection.
2.3.2.3. The silica standard allows the PLHCP to order additional tests or test at a greater frequency than required by the standard, if deemed appropriate. Therefore, PLHCPs might perform periodic ( e.g., annual) TB testing as appropriate, based on employees' risk factors. For example, according to the American Thoracic Society (ATS), the diagnosis of silicosis or exposure to silica for 25 years or more are indications for annual TB testing (ATS 1997). PLHCPs should consult the current CDC guidance on risk factors for TB ( See Section 5 of this Appendix).
2.3.2.4. Employees with positive TB tests and those with indeterminate test results should be referred to the appropriate agency or specialist, depending on the test results and clinical picture. Agencies, such as local public health departments, or specialists, such as a pulmonary or infectious disease specialist, may be the appropriate referral. Active TB is a nationally notifiable disease. PLHCPs should be aware of the reporting requirements for their region. All States have TB Control Offices that can be contacted for further information. ( See Section 5 of this Appendix for links to CDC's TB resources and State TB Control Offices.)
2.3.2.5. The following public health principles are key to TB control in the U.S. (ATS-CDC-IDSA 2005):
2.4. Pulmonary Function Testing.
2.4.1. The respirable crystalline silica standard requires the following: Pulmonary function testing must be performed on the initial examination and every three years thereafter. The required pulmonary function test is spirometry and must include forced vital capacity (FVC), forced expiratory volume in one second (FEV 1 ), and FEV 1 /FVC ratio. Testing must be administered by a spirometry technician with a current certificate from a National Institute for Occupational Health and Safety (NIOSH)-approved spirometry course.
2.4.2. Additional guidance and recommendations: Spirometry provides information about individual respiratory status and can be used to track an employee's respiratory status over time or as a surveillance tool to follow individual and group respiratory function. For quality results, the ATS and the American College of Occupational and Environmental Medicine (ACOEM) recommend use of the third National Health and Nutrition Examination Survey (NHANES III) values, and ATS publishes recommendations for spirometry equipment (Miller et al. 2005; Townsend 2011; Redlich et al. 2014). OSHA's publication, Spirometry Testing in Occupational Health Programs: Best Practices for Healthcare Professionals, provides helpful guidance ( See Section 5 of this Appendix). Abnormal spirometry results may warrant further clinical evaluation and possible recommendations for limitations on the employee's exposure to respirable crystalline silica.
2.5. Chest X-ray.
2.5.1. The respirable crystalline silica standard requires the following: A single posteroanterior (PA) radiographic projection or radiograph of the chest at full inspiration recorded on either film (no less than 14 x 17 inches and no more than 16 x 17 inches) or digital radiography systems. A chest X-ray must be performed on the initial examination and every three years thereafter. The chest X-ray must be interpreted and classified according to the International Labour Office (ILO) International Classification of Radiographs of Pneumoconioses by a NIOSH-certified B Reader.
Chest radiography is necessary to diagnose silicosis, monitor the progression of silicosis, and identify associated conditions such as TB. If the B reading indicates small opacities in a profusion of 1/0 or higher, the employee is to receive a recommendation for referral to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine.
2.5.2. Additional guidance and recommendations: Medical imaging has largely transitioned from conventional film-based radiography to digital radiography systems. The ILO Guidelines for the Classification of Pneumoconioses has historically provided film-based chest radiography as a referent standard for comparison to individual exams. However, in 2011, the ILO revised the guidelines to include a digital set of referent standards that were derived from the prior film-based standards. To assist in assuring that digitally-acquired radiographs are at least as safe and effective as film radiographs, NIOSH has prepared guidelines, based upon accepted contemporary professional recommendations ( See Section 5 of this Appendix). Current research from Laney et al. 2011 and Halldin et al. 2014 validate the use of the ILO digital referent images. Both studies conclude that the results of pneumoconiosis classification using digital references are comparable to film-based ILO classifications. Current ILO guidance on radiography for pneumoconioses and B-reading should be reviewed by the PLHCP periodically, as needed, on the ILO or NIOSH Web sites ( See Section 5 of this Appendix).
2.6. Other Testing. Under the respirable crystalline silica standards, the PLHCP has the option of ordering additional testing he or she deems appropriate. Additional tests can be ordered on a case-by-case basis depending on individual signs or symptoms and clinical judgment. For example, if an employee reports a history of abnormal kidney function tests, the PLHCP may want to order a baseline renal function tests ( e.g., serum creatinine and urinalysis). As indicated above, the PLHCP may order annual TB testing for silica-exposed employees who are at high risk of developing active TB infections. Additional tests that PLHCPs may order based on findings of medical examinations include, but is not limited to, chest computerized tomography (CT) scan for lung cancer or COPD, testing for immunologic diseases, and cardiac testing for pulmonary-related heart disease, such as cor pulmonale.
3. Roles and Responsibilities
3.1. PLHCP. The PLHCP designation refers to “an individual whose legally permitted scope of practice ( i.e., license, registration, or certification) allows him or her to independently provide or be delegated the responsibility to provide some or all of the particular health care services required” by the respirable crystalline silica standard. The legally permitted scope of practice for the PLHCP is determined by each State. PLHCPs who perform clinical services for a silica medical surveillance program should have a thorough knowledge of respirable crystalline silica-related diseases and symptoms. Suspected cases of silicosis, advanced COPD, or other respiratory conditions causing impairment should be promptly referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine.
Once the medical surveillance examination is completed, the employer must ensure that the PLHCP explains to the employee the results of the medical examination and provides the employee with a written medical report within 30 days of the examination. The written medical report must contain a statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment. In addition, the PLHCP's written medical report must include any recommended limitations on the employee's use of respirators, any recommended limitations on the employee's exposure to respirable crystalline silica, and a statement that the employee should be examined by a Board Certified Specialist in Pulmonary Disease or Occupational medicine if the chest X-ray is classified as 1/0 or higher by the B Reader, or if referral to a Specialist is otherwise deemed appropriate by the PLHCP.
The PLHCP should discuss all findings and test results and any recommendations regarding the employee's health, worksite safety and health practices, and medical referrals for further evaluation, if indicated. In addition, it is suggested that the PLHCP offer to provide the employee with a complete copy of their examination and test results, as some employees may want this information for their own records or to provide to their personal physician or a future PLHCP. Employees are entitled to access their medical records.
Under the respirable crystalline silica standard, the employer must ensure that the PLHCP provides the employer with a written medical opinion within 30 days of the employee examination, and that the employee also gets a copy of the written medical opinion for the employer within 30 days. The PLHCP may choose to directly provide the employee a copy of the written medical opinion. This can be particularly helpful to employees, such as construction employees, who may change employers frequently. The written medical opinion can be used by the employee as proof of up-to-date medical surveillance. The following lists the elements of the written medical report for the employee and written medical opinion for the employer. (Sample forms for the written medical report for the employee, the written medical opinion for the employer, and the written authorization are provided in Section 7 of this Appendix.)
3.1.1. The written medical report for the employee must include the following information:
3.1.1.1. A statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment;
3.1.1.2. Any recommended limitations upon the employee's use of a respirator;
3.1.1.3. Any recommended limitations on the employee's exposure to respirable crystalline silica; and
3.1.1.4. A statement that the employee should be examined by a Board Certified Specialist in Pulmonary Disease or Occupational Medicine, where the standard requires or where the PLHCP has determined such a referral is necessary. The standard requires referral to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for a chest X-ray B reading indicating small opacities in a profusion of 1/0 or higher, or if the PHLCP determines that referral to a Specialist is necessary for other silica-related findings.
3.1.2. The PLHCP's written medical opinion for the employer must include only the following information:
3.1.2.1. The date of the examination;
3.1.2.2. A statement that the examination has met the requirements of this section; and
3.1.2.3. Any recommended limitations on the employee's use of respirators.
3.1.2.4. If the employee provides the PLHCP with written authorization, the written opinion for the employer shall also contain either or both of the following:
3.1.2.5. In addition to the above referral for abnormal chest X-ray, the PLHCP may refer an employee to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for other findings of concern during the medical surveillance examination if these findings are potentially related to silica exposure.
3.1.2.6. Although the respirable crystalline silica standard requires the employer to ensure that the PLHCP explains the results of the medical examination to the employee, the standard does not mandate how this should be done. The written medical opinion for the employer could contain a statement that the PLHCP has explained the results of the medical examination to the employee.
3.2. Medical Specialists. The silica standard requires that all employees with chest X-ray B readings of 1/0 or higher be referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine. If the employee has given written authorization for the employer to be informed, then the employer shall make available a medical examination by a Specialist within 30 days after receiving the PLHCP's written medical opinion.
3.2.1. The employer must provide the following information to the Board Certified Specialist in Pulmonary Disease or Occupational Medicine:
3.2.1.1. A description of the employee's former, current, and anticipated duties as they relate to the employee's occupational exposure to respirable crystalline silica;
3.2.1.2. The employee's former, current, and anticipated levels of occupational exposure to respirable crystalline silica;
3.2.1.3. A description of any personal protective equipment used or to be used by the employee, including when and for how long the employee has used or will use that equipment; and
3.2.1.4. Information from records of employment-related medical examinations previously provided to the employee and currently within the control of the employer.
3.2.2. The PLHCP should make certain that, with written authorization from the employee, the Board Certified Specialist in Pulmonary Disease or Occupational Medicine has any other pertinent medical and occupational information necessary for the specialist's evaluation of the employee's condition.
3.2.3. Once the Board Certified Specialist in Pulmonary Disease or Occupational Medicine has evaluated the employee, the employer must ensure that the Specialist explains to the employee the results of the medical examination and provides the employee with a written medical report within 30 days of the examination. The employer must also ensure that the Specialist provides the employer with a written medical opinion within 30 days of the employee examination. (Sample forms for the written medical report for the employee, the written medical opinion for the employer and the written authorization are provided in Section 7 of this Appendix.)
3.2.4. The Specialist's written medical report for the employee must include the following information:
3.2.4.1. A statement indicating the results of the medical examination, including any medical condition(s) that would place the employee at increased risk of material impairment to health from exposure to respirable crystalline silica and any medical conditions that require further evaluation or treatment;
3.2.4.2. Any recommended limitations upon the employee's use of a respirator; and
3.2.4.3. Any recommended limitations on the employee's exposure to respirable crystalline silica.
3.2.5. The Specialist's written medical opinion for the employer must include the following information:
3.2.5.1. The date of the examination; and
3.2.5.2. Any recommended limitations on the employee's use of respirators.
3.2.5.3. If the employee provides the Board Certified Specialist in Pulmonary Disease or Occupational Medicine with written authorization, the written medical opinion for the employer shall also contain any recommended limitations on the employee's exposure to respirable crystalline silica.
3.2.5.4. Although the respirable crystalline silica standard requires the employer to ensure that the Board Certified Specialist in Pulmonary Disease or Occupational Medicine explains the results of the medical examination to the employee, the standard does not mandate how this should be done. The written medical opinion for the employer could contain a statement that the Specialist has explained the results of the medical examination to the employee.
3.2.6. After evaluating the employee, the Board Certified Specialist in Pulmonary Disease or Occupational Medicine should provide feedback to the PLHCP as appropriate, depending on the reason for the referral. OSHA believes that because the PLHCP has the primary relationship with the employer and employee, the Specialist may want to communicate his or her findings to the PLHCP and have the PLHCP simply update the original medical report for the employee and medical opinion for the employer. This is permitted under the standard, so long as all requirements and time deadlines are met.
3.3. Public Health Professionals. PLHCPs might refer employees or consult with public health professionals as a result of silica medical surveillance. For instance, if individual cases of active TB are identified, public health professionals from state or local health departments may assist in diagnosis and treatment of individual cases and may evaluate other potentially affected persons, including coworkers. Because silica-exposed employees are at increased risk of progression from latent to active TB, treatment of latent infection is recommended. The diagnosis of active TB, acute or accelerated silicosis, or other silica-related diseases and infections should serve as sentinel events suggesting high levels of exposure to silica and may require consultation with the appropriate public health agencies to investigate potentially similarly exposed coworkers to assess for disease clusters. These agencies include local or state health departments or OSHA. In addition, NIOSH can provide assistance upon request through their Health Hazard Evaluation program. ( See Section 5 of this Appendix)
4. Confidentiality and Other Considerations
The information that is provided from the PLHCP to the employee and employer under the medical surveillance section of OSHA's respirable crystalline silica standard differs from that of medical surveillance requirements in previous OSHA standards. The standard requires two separate written communications, a written medical report for the employee and a written medical opinion for the employer. The confidentiality requirements for the written medical opinion are more stringent than in past standards. For example, the information the PLHCP can (and must) include in his or her written medical opinion for the employer is limited to: The date of the examination, a statement that the examination has met the requirements of this section, and any recommended limitations on the employee's use of respirators. If the employee provides written authorization for the disclosure of any limitations on the employee's exposure to respirable crystalline silica, then the PLHCP can (and must) include that information in the written medical opinion for the employer as well. Likewise, with the employee's written authorization, the PLHCP can (and must) disclose the PLHCP's referral recommendation (if any) as part of the written medical opinion for the employer. However, the opinion to the employer must not include information regarding recommended limitations on the employee's exposure to respirable crystalline silica or any referral recommendations without the employee's written authorization.
The standard also places limitations on the information that the Board Certified Specialist in Pulmonary Disease or Occupational Medicine can provide to the employer without the employee's written authorization. The Specialist's written medical opinion for the employer, like the PLHCP's opinion, is limited to (and must contain): The date of the examination and any recommended limitations on the employee's use of respirators. If the employee provides written authorization, the written medical opinion can (and must) also contain any limitations on the employee's exposure to respirable crystalline silica.
The PLHCP should discuss the implication of signing or not signing the authorization with the employee (in a manner and language that he or she understands) so that the employee can make an informed decision regarding the written authorization and its consequences. The discussion should include the risk of ongoing silica exposure, personal risk factors, risk of disease progression, and possible health and economic consequences. For instance, written authorization is required for a PLHCP to advise an employer that an employee should be referred to a Board Certified Specialist in Pulmonary Disease or Occupational Medicine for evaluation of an abnormal chest X-ray (B-reading 1/0 or greater). If an employee does not sign an authorization, then the employer will not know and cannot facilitate the referral to a Specialist and is not required to pay for the Specialist's examination. In the rare case where an employee is diagnosed with acute or accelerated silicosis, co-workers are likely to be at significant risk of developing those diseases as a result of inadequate controls in the workplace. In this case, the PLHCP and/or Specialist should explain this concern to the affected employee and make a determined effort to obtain written authorization from the employee so that the PLHCP and/or Specialist can contact the employer.
Finally, without written authorization from the employee, the PLHCP and/or Board Certified Specialist in Pulmonary Disease or Occupational Medicine cannot provide feedback to an employer regarding control of workplace silica exposure, at least in relation to an individual employee. However, the regulation does not prohibit a PLHCP and/or Specialist from providing an employer with general recommendations regarding exposure controls and prevention programs in relation to silica exposure and silica-related illnesses, based on the information that the PLHCP receives from the employer such as employees' duties and exposure levels. Recommendations may include increased frequency of medical surveillance examinations, additional medical surveillance components, engineering and work practice controls, exposure monitoring and personal protective equipment. For instance, more frequent medical surveillance examinations may be a recommendation to employers for employees who do abrasive blasting with silica because of the high exposures associated with that operation.
ACOEM's Code of Ethics and discussion is a good resource to guide PLHCPs regarding the issues discussed in this section ( See Section 5 of this Appendix).
5. Resources
5.1. American College of Occupational and Environmental Medicine (ACOEM):
http://www.acoem.org/codeofconduct.aspx
J Occup Environ Med
5.2. Center for Disease Control and Prevention (CDC)
http://www.cdc.gov/tb/default.htm
http://www.cdc.gov/tb/links/tboffices.htm
http://www.cdc.gov/tb/programs/laws/default.htm
http://www.cdc.gov/tb/publications/ltbi/pdf/targetedltbi.pdf
5.3. International Labour Organization
http://www.ilo.org/safework/info/publications/WCMS_168260/lang-en/index.htm
5.4. National Institute of Occupational Safety and Health (NIOSH)
http://www.cdc.gov/niosh/topics/chestradiography/breader-info.html
http://www.cdc.gov/niosh/docs/2011-198/
http://www.cdc.gov/niosh/docs/2002-129/
http://www.cdc.gov/niosh/hhe/
5.5. National Industrial Sand Association:
http://www.sand.org/silica-occupational-health-program
5.6. Occupational Safety and Health Administration (OSHA)
http://www.osha.gov/html/Feed_Back.html
http://www.osha.gov/dts/oom/clinicians/index.html
http://www.osha.gov/dsg/topics/silicacrystalline/index.html
http://www.osha.gov/Publications/OSHA3637.pdf
http://www.osha.gov/Publications/osha3415.pdf
http://www.osha.gov/Publications/osha3418.pdf
5.7. Other
CA Cancer J Clin
6. References
Am J Respir Crit Care Med
Morbidity and Mortality Weekly Report (MMWR)
http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5412a1.htm
Occupational Medicine
Acad Radiol
International Agency for Research on Cancer. (2012). Monographs on the evaluation of carcinogenic risks to humans: Arsenic, Metals, Fibers, and Dusts Silica Dust, Crystalline, in the Form of Quartz or Cristobalite. A Review of Human Carcinogens. Volume 100 C. Geneva, Switzerland: World Health Organization.
Jalloul, A.S. and Banks D.E. (2007). Chapter 23. The health effects of silica exposure. In: Rom, W.N. and Markowitz, S.B. (Eds). Environmental and Occupational Medicine, 4th edition. Lippincott, Williams and Wilkins, Philadelphia, 365-387.
Chest
Chest
Am J Epi
Epidemiology
Morbidity and Mortality Weekly Report (MMWR)
Eur Respir J
http://ntp.niehs.nih.gov/ntp/roc/content/profiles/silica.pdf
Occupational Safety and Health Administration/National Institute for Occupational Safety and Health (OSHA/NIOSH) (2012). Hazard Alert. Worker exposure to silica during hydraulic fracturing.
Occupational Safety and Health Administration/National Institute for Occupational Safety and Health (OSHA/NIOSH) (2015). Hazard alert. Worker exposure to silica during countertop manufacturing, finishing, and installation. (OSHA-HA-3768-2015).
Am J Respir Crit Care Med
Int J Tuberc Lung Dis
Occup Med
Am J Respir Crit Care Med,
Cancer Causes Control,
CA Cancer J Clin,
J Occup Environ Med,
7. Sample Forms
Three sample forms are provided. The first is a sample written medical report for the employee. The second is a sample written medical opinion for the employer. And the third is a sample written authorization form that employees sign to clarify what information the employee is authorizing to be released to the employer.
[81 FR 16876, Mar. 25, 2016]
This standard does not apply to:
The following terms are defined for the purposes of this subpart only:
Acceptable entry conditions means the conditions that must exist in a permit space, before an employee may enter that space, to ensure that employees can safely enter into, and safely work within, the space.
Attendant means an individual stationed outside one or more permit spaces who assesses the status of authorized entrants and who must perform the duties specified in § 1926.1209.
Authorized entrant means an employee who is authorized by the entry supervisor to enter a permit space.
Barrier means a physical obstruction that blocks or limits access.
Blanking or blinding means the absolute closure of a pipe, line, or duct by the fastening of a solid plate (such as a spectacle blind or a skillet blind) that completely covers the bore and that is capable of withstanding the maximum pressure of the pipe, line, or duct with no leakage beyond the plate.
Competent person means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has the authorization to take prompt corrective measures to eliminate them.
Confined space means a space that:
Control means the action taken to reduce the level of any hazard inside a confined space using engineering methods (for example, by ventilation), and then using these methods to maintain the reduced hazard level. Control also refers to the engineering methods used for this purpose. Personal protective equipment is not a control.
Controlling Contractor is the employer that has overall responsibility for construction at the worksite.
Double block and bleed means the closure of a line, duct, or pipe by closing and locking or tagging two in-line valves and by opening and locking or tagging a drain or vent valve in the line between the two closed valves.
Early-warning system means the method used to alert authorized entrants and attendants that an engulfment hazard may be developing. Examples of early-warning systems include, but are not limited to: Alarms activated by remote sensors; and lookouts with equipment for immediately communicating with the authorized entrants and attendants.
Emergency means any occurrence (including any failure of power, hazard control or monitoring equipment) or event, internal or external, to the permit space that could endanger entrants.
Engulfment means the surrounding and effective capture of a person by a liquid or finely divided (flowable) solid substance that can be aspirated to cause death by filling or plugging the respiratory system or that can exert enough force on the body to cause death by strangulation, constriction, crushing, or suffocation.
Entry means the action by which any part of a person passes through an opening into a permit-required confined space. Entry includes ensuing work activities in that space and is considered to have occurred as soon as any part of the entrant's body breaks the plane of an opening into the space, whether or not such action is intentional or any work activities are actually performed in the space.
Entry Employer means any employer who decides that an employee it directs will enter a permit space.
Entry permit (permit) means the written or printed document that is provided by the employer who designated the space a permit space to allow and control entry into a permit space and that contains the information specified in § 1926.1206.
Entry rescue occurs when a rescue service enters a permit space to rescue one or more employees.
Entry supervisor means the qualified person (such as the employer, foreman, or crew chief) responsible for determining if acceptable entry conditions are present at a permit space where entry is planned, for authorizing entry and overseeing entry operations, and for terminating entry as required by this standard.
Hazard means a physical hazard or hazardous atmosphere. See definitions below.
Hazardous atmosphere means an atmosphere that may expose employees to the risk of death, incapacitation, impairment of ability to self-rescue (that is, escape unaided from a permit space), injury, or acute illness from one or more of the following causes:
Host employer means the employer that owns or manages the property where the construction work is taking place.
Hot work means operations capable of providing a source of ignition (for example, riveting, welding, cutting, burning, and heating).
Immediately dangerous to life or health (IDLH) means any condition that would interfere with an individual's ability to escape unaided from a permit space and that poses a threat to life or that would cause irreversible adverse health effects.
Inerting means displacing the atmosphere in a permit space by a noncombustible gas (such as nitrogen) to such an extent that the resulting atmosphere is noncombustible.
Isolate or isolation means the process by which employees in a confined space are completely protected against the release of energy and material into the space, and contact with a physical hazard, by such means as: Blanking or blinding; misaligning or removing sections of lines, pipes, or ducts; a double block and bleed system; lockout or tagout of all sources of energy; blocking or disconnecting all mechanical linkages; or placement of barriers to eliminate the potential for employee contact with a physical hazard.
Limited or restricted means for entry or exit means a condition that has a potential to impede an employee's movement into or out of a confined space. Such conditions include, but are not limited to, trip hazards, poor illumination, slippery floors, inclining surfaces and ladders.
Line breaking means the intentional opening of a pipe, line, or duct that is or has been carrying flammable, corrosive, or toxic material, an inert gas, or any fluid at a volume, pressure, or temperature capable of causing injury.
Lockout means the placement of a lockout device on an energy isolating device, in accordance with an established procedure, ensuring that the energy isolating device and the equipment being controlled cannot be operated until the lockout device is removed.
Lower flammable limit or lower explosive limit means the minimum concentration of a substance in air needed for an ignition source to cause a flame or explosion.
Monitor or monitoring means the process used to identify and evaluate the hazards after an authorized entrant enters the space. This is a process of checking for changes that is performed in a periodic or continuous manner after the completion of the initial testing or evaluation of that space.
Non-entry rescue occurs when a rescue service, usually the attendant, retrieves employees in a permit space without entering the permit space.
Non-permit confined space means a confined space that meets the definition of a confined space but does not meet the requirements for a permit-required confined space, as defined in this subpart.
Oxygen deficient atmosphere means an atmosphere containing less than 19.5 percent oxygen by volume.
Oxygen enriched atmosphere means an atmosphere containing more than 23.5 percent oxygen by volume.
Permit-required confined space (permit space) means a confined space that has one or more of the following characteristics:
Permit-required confined space program (permit space program) means the employer's overall program for controlling, and, where appropriate, for protecting employees from, permit space hazards and for regulating employee entry into permit spaces.
Physical hazard means an existing or potential hazard that can cause death or serious physical damage. Examples include, but are not limited to: Explosives (as defined by paragraph (n) of § 1926.914, definition of “explosive”); mechanical, electrical, hydraulic and pneumatic energy; radiation; temperature extremes; engulfment; noise; and inwardly converging surfaces. Physical hazard also includes chemicals that can cause death or serious physical damage through skin or eye contact (rather than through inhalation).
Prohibited condition means any condition in a permit space that is not allowed by the permit during the period when entry is authorized. A hazardous atmosphere is a prohibited condition unless the employer can demonstrate that personal protective equipment (PPE) will provide effective protection for each employee in the permit space and provides the appropriate PPE to each employee.
Qualified person means one who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated his ability to solve or resolve problems relating to the subject matter, the work, or the project.
Representative permit space means a mock-up of a confined space that has entrance openings that are similar to, and is of similar size, configuration, and accessibility to, the permit space that authorized entrants enter.
Rescue means retrieving, and providing medical assistance to, one or more employees who are in a permit space.
Rescue service means the personnel designated to rescue employees from permit spaces.
Retrieval system means the equipment (including a retrieval line, chest or full body harness, wristlets or anklets, if appropriate, and a lifting device or anchor) used for non-entry rescue of persons from permit spaces.
Serious physical damage means an impairment or illness in which a body part is made functionally useless or is substantially reduced in efficiency. Such impairment or illness may be permanent or temporary and includes, but is not limited to, loss of consciousness, disorientation, or other immediate and substantial reduction in mental efficiency. Injuries involving such impairment would usually require treatment by a physician or other licensed health-care professional.
Tagout means:
Test or testing means the process by which the hazards that may confront entrants of a permit space are identified and evaluated. Testing includes specifying the tests that are to be performed in the permit space.
Ventilate or ventilation means controlling a hazardous atmosphere using continuous forced-air mechanical systems that meet the requirements of § 1926.57 (Ventilation).
Each entry employer must:
The entry permit that documents compliance with this section and authorizes entry to a permit space must identify:
The entry employer must ensure that all authorized entrants:
The entry employer must ensure that each attendant:
The entry employer must ensure that each entry supervisor:
For each document required to be retained in this standard, the retaining employer must make the document available on request to the Secretary of Labor or the Secretary's designee.
This standard applies to equipment included in paragraph (a) of this section when used with attachments. Such attachments, whether crane-attached or suspended include, but are not limited to: Hooks, magnets, grapples, clamshell buckets, orange peel buckets, concrete buckets, drag lines, personnel platforms, augers or drills and pile driving equipment.
This subpart does not cover:
Flash-butt welding trucks or other roadway maintenance machines not equipped with any hoisting device other than that used to suspend and move a welding device or workhead assembly. For purposes of this paragraph (c)(18), the terms flash-butt welding truck and roadway maintenance machine refer to railroad equipment that meets the definition of “roadway maintenance machine” in 49 CFR 214.7 and is used only for railroad track work.
[75 FR 48135, Aug. 9, 2010, as amended at 78 FR 32116, May 29, 2013; 79 FR 20743, Apr. 11, 2014; 85 FR 57122, Sept. 15, 2020]
A/D director (Assembly/Disassembly director) means an individual who meets this subpart's requirements for an A/D director, irrespective of the person's formal job title or whether the person is non-management or management personnel.
Articulating crane means a crane whose boom consists of a series of folding, pin connected structural members, typically manipulated to extend or retract by power from hydraulic cylinders.
Assembly/Disassembly means the assembly and/or disassembly of equipment covered under this standard. With regard to tower cranes, “erecting and climbing” replaces the term “assembly,” and “dismantling” replaces the term “disassembly.” Regardless of whether the crane is initially erected to its full height or is climbed in stages, the process of increasing the height of the crane is an erection process.
Assist crane means a crane used to assist in assembling or disassembling a crane.
Attachments means any device that expands the range of tasks that can be done by the equipment. Examples include, but are not limited to: An auger, drill, magnet, pile-driver, and boom-attached personnel platform.
Audible signal means a signal made by a distinct sound or series of sounds. Examples include, but are not limited to, sounds made by a bell, horn, or whistle.
Blocking (also referred to as “cribbing”) is wood or other material used to support equipment or a component and distribute loads to the ground. It is typically used to support lattice boom sections during assembly/disassembly and under outrigger and stabilizer floats.
Boatswain's chair means a single-point adjustable suspension scaffold consisting of a seat or sling (which may be incorporated into a full body harness) designed to support one employee in a sitting position.
Bogie means “travel bogie,” which is defined below.
Boom (equipment other than tower crane) means an inclined spar, strut, or other long structural member which supports the upper hoisting tackle on a crane or derrick. Typically, the length and vertical angle of the boom can be varied to achieve increased height or height and reach when lifting loads. Booms can usually be grouped into general categories of hydraulically extendible, cantilevered type, latticed section, cable supported type or articulating type.
Boom (tower cranes): On tower cranes, if the “boom” ( i.e., principal horizontal structure) is fixed, it is referred to as a jib; if it is moveable up and down, it is referred to as a boom.
Boom angle indicator means a device which measures the angle of the boom relative to horizontal.
Boom hoist limiting device includes boom hoist disengaging device, boom hoist shut-off, boom hoist disconnect, boom hoist hydraulic relief, boom hoist kick-outs, automatic boom stop device, or derricking limiter. This type of device disengages boom hoist power when the boom reaches a predetermined operating angle. It also sets brakes or closes valves to prevent the boom from lowering after power is disengaged.
Boom length indicator indicates the length of the permanent part of the boom (such as ruled markings on the boom) or, as in some computerized systems, the length of the boom with extensions/attachments.
Boom stop includes boom stops, (belly straps with struts/standoff), telescoping boom stops, attachment boom stops, and backstops. These devices restrict the boom from moving above a certain maximum angle and toppling over backward.
Boom suspension system means a system of pendants, running ropes, sheaves, and other hardware which supports the boom tip and controls the boom angle.
Builder means the builder/constructor of equipment.
Center of gravity: The center of gravity of any object is the point in the object around which its weight is evenly distributed. If you could put a support under that point, you could balance the object on the support.
Certified welder means a welder who meets nationally recognized certification requirements applicable to the task being performed.
Climbing means the process in which a tower crane is raised to a new working height, either by adding additional tower sections to the top of the crane (top climbing), or by a system in which the entire crane is raised inside the structure (inside climbing).
Come-a-long means a mechanical device typically consisting of a chain or cable attached at each end that is used to facilitate movement of materials through leverage.
Competent person means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.
Controlled load lowering means lowering a load by means of a mechanical hoist drum device that allows a hoisted load to be lowered with maximum control using the gear train or hydraulic components of the hoist mechanism. Controlled load lowering requires the use of the hoist drive motor, rather than the load hoist brake, to lower the load.
Controlling entity means an employer that is a prime contractor, general contractor, construction manager or any other legal entity which has the overall responsibility for the construction of the project—its planning, quality and completion.
Counterweight means a weight used to supplement the weight of equipment in providing stability for lifting loads by counterbalancing those loads.
Crane/derrick includes all equipment covered by this subpart.
Crawler crane means equipment that has a type of base mounting which incorporates a continuous belt of sprocket driven track.
Crossover points means locations on a wire rope which is spooled on a drum where one layer of rope climbs up on and crosses over the previous layer. This takes place at each flange of the drum as the rope is spooled onto the drum, reaches the flange, and begins to wrap back in the opposite direction.
Dedicated channel means a line of communication assigned by the employer who controls the communication system to only one signal person and crane/derrick or to a coordinated group of cranes/derricks/signal person(s).
Dedicated pile-driver is a machine that is designed to function exclusively as a pile-driver. These machines typically have the ability to both hoist the material that will be pile-driven and to pile-drive that material.
Dedicated spotter (power lines): To be considered a dedicated spotter, the requirements of § 1926.1428 (Signal person qualifications) must be met and his/her sole responsibility is to watch the separation between the power line and the equipment, load line and load (including rigging and lifting accessories), and ensure through communication with the operator that the applicable minimum approach distance is not breached.
Directly under the load means a part or all of an employee is directly beneath the load.
Dismantling includes partial dismantling (such as dismantling to shorten a boom or substitute a different component).
Drum rotation indicator means a device on a crane or hoist which indicates in which direction and at what relative speed a particular hoist drum is turning.
Electrical contact occurs when a person, object, or equipment makes contact or comes in close proximity with an energized conductor or equipment that allows the passage of current.
Employer-made equipment means floating cranes/derricks designed and built by an employer for the employer's own use.
Encroachment is where any part of the crane, load line or load (including rigging and lifting accessories) breaches a minimum clearance distance that this subpart requires to be maintained from a power line.
Equipment means equipment covered by this subpart.
Equipment criteria means instructions, recommendations, limitations and specifications.
Fall protection equipment means guardrail systems, safety net systems, personal fall arrest systems, positioning device systems or fall restraint systems.
Fall restraint system means a fall protection system that prevents the user from falling any distance. The system is comprised of either a body belt or body harness, along with an anchorage, connectors and other necessary equipment. The other components typically include a lanyard, and may also include a lifeline and other devices.
Fall zone means the area (including but not limited to the area directly beneath the load) in which it is reasonably foreseeable that partially or completely suspended materials could fall in the event of an accident.
Flange points are points of contact between rope and drum flange where the rope changes layers.
Floating cranes/derricks means equipment designed by the manufacturer (or employer) for marine use by permanent attachment to a barge, pontoons, vessel or other means of flotation.
For example means “one example, although there are others.”
Free fall (of the load line) means that only the brake is used to regulate the descent of the load line (the drive mechanism is not used to drive the load down faster or retard its lowering).
Free surface effect is the uncontrolled transverse movement of liquids in compartments which reduce a vessel's transverse stability.
Hoist means a mechanical device for lifting and lowering loads by winding a line onto or off a drum.
Hoisting is the act of raising, lowering or otherwise moving a load in the air with equipment covered by this standard. As used in this standard, “hoisting” can be done by means other than wire rope/hoist drum equipment.
Include/including means “including, but not limited to.”
Insulating link/device means an insulating device listed, labeled, or accepted by a Nationally Recognized Testing Laboratory in accordance with 29 CFR 1910.7.
Jib stop (also referred to as a jib backstop), is the same type of device as a boom stop but is for a fixed or luffing jib.
Land crane/derrick is equipment not originally designed by the manufacturer for marine use by permanent attachment to barges, pontoons, vessels, or other means of floatation.
List means the angle of inclination about the longitudinal axis of a barge, pontoons, vessel or other means of floatation.
Load refers to the object(s) being hoisted and/or the weight of the object(s); both uses refer to the object(s) and the load-attaching equipment, such as, the load block, ropes, slings, shackles, and any other ancillary attachment.
Load moment (or rated capacity) indicator means a system which aids the equipment operator by sensing (directly or indirectly) the overturning moment on the equipment, i.e., load multiplied by radius. It compares this lifting condition to the equipment's rated capacity, and indicates to the operator the percentage of capacity at which the equipment is working. Lights, bells, or buzzers may be incorporated as a warning of an approaching overload condition.
Load moment (or rated capacity) limiter means a system which aids the equipment operator by sensing (directly or indirectly) the overturning moment on the equipment, i.e., load multiplied by radius. It compares this lifting condition to the equipment's rated capacity, and when the rated capacity is reached, it shuts off power to those equipment functions which can increase the severity of loading on the equipment, e.g., hoisting, telescoping out, or luffing out. Typically, those functions which decrease the severity of loading on the equipment remain operational, e.g., lowering, telescoping in, or luffing in.
Locomotive crane means a crane mounted on a base or car equipped for travel on a railroad track.
Luffing jib limiting device is similar to a boom hoist limiting device, except that it limits the movement of the luffing jib.
Marine hoisted personnel transfer device means a device, such as a “transfer net,” that is designed to protect the employees being hoisted during a marine transfer and to facilitate rapid entry into and exit from the device. Such devices do not include boatswain's chairs when hoisted by equipment covered by this standard.
Marine worksite means a construction worksite located in, on or above the water.
Mobile crane means a lifting device incorporating a cable suspended latticed boom or hydraulic telescopic boom designed to be moved between operating locations by transport over the road.
Moving point-to-point means the times during which an employee is in the process of going to or from a work station.
Multi-purpose machine means a machine that is designed to be configured in various ways, at least one of which allows it to hoist (by means of a winch or hook) and horizontally move a suspended load. For example, a machine that can rotate and can be configured with removable forks/tongs (for use as a forklift) or with a winch pack, jib (with a hook at the end) or jib used in conjunction with a winch. When configured with the forks/tongs, it is not covered by this subpart. When configured with a winch pack, jib (with a hook at the end) or jib used in conjunction with a winch, it is covered by this subpart.
Nationally recognized accrediting agency is an organization that, due to its independence and expertise, is widely recognized as competent to accredit testing organizations. Examples of such accrediting agencies include, but are not limited to, the National Commission for Certifying Agencies and the American National Standards Institute.
Nonconductive means that, because of the nature and condition of the materials used, and the conditions of use (including environmental conditions and condition of the material), the object in question has the property of not becoming energized (that is, it has high dielectric properties offering a high resistance to the passage of current under the conditions of use).
Operational aids are devices that assist the operator in the safe operation of the crane by providing information or automatically taking control of a crane function. These include, but are not limited to, the devices listed in § 1926.1416 (“listed operational aids”).
Operational controls means levers, switches, pedals and other devices for controlling equipment operation.
Operator means a person who is operating the equipment.
Overhead and gantry cranes includes overhead/bridge cranes, semigantry, cantilever gantry, wall cranes, storage bridge cranes, launching gantry cranes, and similar equipment, irrespective of whether it travels on tracks, wheels, or other means.
Paragraph refers to a paragraph in the same section of this subpart that the word “paragraph” is used, unless otherwise specified.
Pendants includes both wire and bar types. Wire type: A fixed length of wire rope with mechanical fittings at both ends for pinning segments of wire rope together. Bar type: Instead of wire rope, a bar is used. Pendants are typically used in a latticed boom crane system to easily change the length of the boom suspension system without completely changing the rope on the drum when the boom length is increased or decreased.
Personal fall arrest system means a system used to arrest an employee in a fall from a working level. It consists of an anchorage, connectors, a body harness and may include a lanyard, deceleration device, lifeline, or suitable combination of these.
Portal crane is a type of crane consisting of a rotating upperstructure, hoist machinery, and boom mounted on top of a structural gantry which may be fixed in one location or have travel capability. The gantry legs or columns usually have portal openings in between to allow passage of traffic beneath the gantry.
Power lines means electric transmission and distribution lines.
Procedures include, but are not limited to: Instructions, diagrams, recommendations, warnings, specifications, protocols and limitations.
Proximity alarm is a device that provides a warning of proximity to a power line and that has been listed, labeled, or accepted by a Nationally Recognized Testing Laboratory in accordance with 29 CFR 1910.7.
Qualified evaluator (not a third party) means a person employed by the signal person's employer who has demonstrated that he/she is competent in accurately assessing whether individuals meet the Qualification Requirements in this subpart for a signal person.
Qualified evaluator (third party) means an entity that, due to its independence and expertise, has demonstrated that it is competent in accurately assessing whether individuals meet the Qualification Requirements in this subpart for a signal person.
Qualified person means a person who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training and experience, successfully demonstrated the ability to solve/resolve problems relating to the subject matter, the work, or the project.
Qualified rigger is a rigger who meets the criteria for a qualified person.
Range control limit device is a device that can be set by an equipment operator to limit movement of the boom or jib tip to a plane or multiple planes.
Range control warning device is a device that can be set by an equipment operator to warn that the boom or jib tip is at a plane or multiple planes.
Rated capacity means the maximum working load permitted by the manufacturer under specified working conditions. Such working conditions typically include a specific combination of factors such as equipment configuration, radii, boom length, and other parameters of use.
Rated capacity indicator: See load moment indicator.
Rated capacity limiter: See load moment limiter.
Repetitive pickup points refer to, when operating on a short cycle operation, the rope being used on a single layer and being spooled repetitively over a short portion of the drum.
Running wire rope means a wire rope that moves over sheaves or drums.
Runway means a firm, level surface designed, prepared and designated as a path of travel for the weight and configuration of the crane being used to lift and travel with the crane suspended platform. An existing surface may be used as long as it meets these criteria.
Section means a section of this subpart, unless otherwise specified.
Sideboom crane means a track-type or wheel-type tractor having a boom mounted on the side of the tractor, used for lifting, lowering or transporting a load suspended on the load hook. The boom or hook can be lifted or lowered in a vertical direction only.
Special hazard warnings means warnings of site-specific hazards (for example, proximity of power lines).
Stability (flotation device) means the tendency of a barge, pontoons, vessel or other means of flotation to return to an upright position after having been inclined by an external force.
Standard Method means the protocol in appendix A of this subpart for hand signals.
Such as means “such as, but not limited to.”
Superstructure: See Upperworks.
Tagline means a rope (usually fiber) attached to a lifted load for purposes of controlling load spinning and pendular motions or used to stabilize a bucket or magnet during material handling operations.
Tender means an individual responsible for monitoring and communicating with a diver.
Tilt up or tilt down operation means raising/lowering a load from the horizontal to vertical or vertical to horizontal.
Tower crane is a type of lifting structure which utilizes a vertical mast or tower to support a working boom (jib) in an elevated position. Loads are suspended from the working boom. While the working boom may be of the fixed type (horizontal or angled) or have luffing capability, it can always rotate to swing loads, either by rotating on the top of the tower (top slewing) or by the rotation of the tower (bottom slewing). The tower base may be fixed in one location or ballasted and moveable between locations. Mobile cranes that are configured with luffing jib and/or tower attachments are not considered tower cranes under this section.
Travel bogie (tower cranes) is an assembly of two or more axles arranged to permit vertical wheel displacement and equalize the loading on the wheels.
Trim means angle of inclination about the transverse axis of a barge, pontoons, vessel or other means of floatation.
Two blocking means a condition in which a component that is uppermost on the hoist line such as the load block, hook block, overhaul ball, or similar component, comes in contact with the boom tip, fixed upper block or similar component. This binds the system and continued application of power can cause failure of the hoist rope or other component.
Unavailable procedures means procedures that are no longer available from the manufacturer, or have never been available, from the manufacturer.
Upperstructure: See Upperworks.
Upperworks means the revolving frame of equipment on which the operating machinery (and many cases the engine) are mounted along with the operator's cab. The counterweight is typically supported on the rear of the upperstructure and the boom or other front end attachment is mounted on the front.
Up to means “up to and including.”
Wire rope means a flexible rope constructed by laying steel wires into various patterns of multi-wired strands around a core system to produce a helically wound rope.
When assembling or disassembling equipment (or attachments), the employer must comply with all applicable manufacturer prohibitions and must comply with either:
Employer procedures may be used only where the employer can demonstrate that the procedures used meet the requirements in § 1926.1406.
The A/D director must understand the applicable assembly/disassembly procedures.
The A/D director must review the applicable assembly/disassembly procedures immediately prior to the commencement of assembly/disassembly unless the A/D director understands the procedures and has applied them to the same type and configuration of equipment (including accessories, if any).
Where the employer demonstrates that site constraints require one or more employees to be under the boom, jib, or other components when pins (or similar devices) are being removed, the A/D director must implement procedures that minimize the risk of unintended dangerous movement and minimize the duration and extent of exposure under the boom. ( See Non-mandatory appendix B of this subpart for an example.)
During all phases of assembly/disassembly, rated capacity limits for loads imposed on the equipment, equipment components (including rigging), lifting lugs and equipment accessories, must not be exceeded for the equipment being assembled/disassembled.
The A/D director supervising the assembly/disassembly operation must address the hazards associated with the operation, which include:
Site and ground conditions must be adequate for safe assembly/disassembly operations and to support the equipment during assembly/disassembly ( see § 1926.1402 for ground condition requirements).
The size, amount, condition and method of stacking the blocking must be sufficient to sustain the loads and maintain stability.
When used to support lattice booms or components, blocking must be appropriately placed to:
When using an assist crane, the loads that will be imposed on the assist crane at each phase of assembly/disassembly must be verified in accordance with § 1926.1417(o)(3) before assembly/disassembly begins.
The point(s) of attachment of rigging to a boom (or boom sections or jib or jib sections) must be suitable for preventing structural damage and facilitating safe handling of these components.
The boom sections, boom suspension systems (such as gantry A-frames and jib struts), and components must be rigged or supported to maintain stability upon the removal of the pins.
Suspension ropes and pendants must not be allowed to catch on the boom or jib connection pins or cotter pins (including keepers and locking pins).
The potential for unintended movement from inadequately supported counterweights and from hoisting counterweights.
Each time reliance is to be placed on the boom hoist brake to prevent boom movement during assembly/disassembly, the brake must be tested prior to such reliance to determine if it is sufficient to prevent boom movement. If it is not sufficient, a boom hoist pawl, other locking device/back-up braking device, or another method of preventing dangerous movement of the boom (such as blocking or using an assist crane) from a boom hoist brake failure must be used.
Backward stability before swinging the upperworks, travel, and when attaching or removing equipment components.
The effect of wind speed and weather on the equipment.
Manufacturer limitations on the maximum amount of boom supported only by cantilevering must not be exceeded. Where these are unavailable, a registered professional engineer familiar with the type of equipment involved must determine in writing this limitation, which must not be exceeded.
The weight of each of the components must be readily available.
Upon completion of assembly, the equipment must be inspected to ensure compliance with paragraph (m)(1) of this section ( see § 1926.1412(c) for post-assembly inspection requirements).
Reusable shipping pins, straps, links, and similar equipment must be removed. Once they are removed they must either be stowed or otherwise stored so that they do not present a falling object hazard.
Equipment used for pile driving must not have a jib attached during pile driving operations.
When the load to be handled and the operating radius require the use of outriggers or stabilizers, or at any time when outriggers or stabilizers are used, all of the following requirements must be met (except as otherwise indicated):
In addition to following the requirements in 29 CFR 1926.251 and other requirements in this and other standards applicable to rigging, when rigging is used for assembly/disassembly, the employer must ensure that:
Abrasive, sharp or acute edges, and configurations that could cause a reduction of the sling's rated capacity, such as distortion or localized compression.
Dismantling (including dismantling for changing the length of) booms and jibs.
Employer procedures must be developed by a qualified person.
Confirm from the utility owner/operator that the power line has been deenergized and visibly grounded at the worksite.
20 foot clearance. Ensure that no part of the equipment, load line or load (including rigging and lifting accessories), gets closer than 20 feet to the power line by implementing the measures specified in paragraph (b) of this section.
Where encroachment precautions are required under Option (2), or Option (3) of this section, all of the following requirements must be met:
The additional measures are:
No part of a crane/derrick, load line, or load (including rigging and lifting accessories), whether partially or fully assembled, is allowed below a power line unless the employer has confirmed that the utility owner/operator has deenergized and (at the worksite) visibly grounded the power line.
No part of a crane/derrick, load line, or load (including rigging and lifting accessories), whether partially or fully assembled, is allowed closer than the minimum approach distance under Table A ( see § 1926.1408) to a power line unless the employer has confirmed that the utility owner/operator has deenergized and (at the worksite) visibly grounded the power line.
Where Option (3) of this section is used, the utility owner/operator of the power lines must provide the requested voltage information within two working days of the employer's request.
The employer must assume that all power lines are energized unless the utility owner/operator confirms that the power line has been and continues to be deenergized and visibly grounded at the worksite.
There must be at least one electrocution hazard warning conspicuously posted in the cab so that it is in view of the operator and (except for overhead gantry and tower cranes) at least two on the outside of the equipment.
Before beginning equipment operations, the employer must:
Confirm from the utility owner/operator that the power line has been deenergized and visibly grounded at the worksite.
20 foot clearance. Ensure that no part of the equipment, load line, or load (including rigging and lifting accessories), gets closer than 20 feet to the power line by implementing the measures specified in paragraph (b) of this section.
Where encroachment precautions are required under Option (2) or Option (3) of this section, all of the following requirements must be met:
Where Option (3) of this section is used, the utility owner/operator of the power lines must provide the requested voltage information within two working days of the employer's request.
Paragraph (d)(1) of this section is inapplicable where the employer demonstrates that one of the following applies:
The uppermost part of the equipment, with the boom at true vertical, would be more than 20 feet below the plane of the power line or more than the Table A of this section minimum clearance distance below the plane of the power line.
The uppermost part of the equipment, with the boom in the fully extended position, at true vertical, would be more than 20 feet below the plane of the power line or more than the Table A of this section minimum clearance distance below the plane of the power line.
The employer must assume that all power lines are energized unless the utility owner/operator confirms that the power line has been and continues to be deenergized and visibly grounded at the worksite.
| Voltage (nominal, kV, alternating current) | Minimum clearance distance (feet) |
|---|---|
| up to 50 | 10 |
| over 50 to 200 | 15 |
| over 200 to 350 | 20 |
| over 350 to 500 | 25 |
| over 500 to 750 | 35 |
| over 750 to 1,000 | 45 |
| over 1,000 | (as established by the utility owner/operator or registered professional engineer who is a qualified person with respect to electrical power transmission and distribution). |
| Note: The value that follows “to” is up to and includes that value. For example, over 50 to 200 means up to and including 200kV. |
The requirements of §§ 1926.1407 and 1926.1408 apply to power lines over 350 kV except:
Equipment operations in which any part of the equipment, load line, or load (including rigging and lifting accessories) is closer than the minimum approach distance under Table A of § 1926.1408 to an energized power line is prohibited, except where the employer demonstrates that all of the following requirements are met:
[75 FR 48135, Aug. 9, 2010, as amended at 79 FR 20743, Apr. 11, 2014]
If any part of the equipment while traveling will get closer than 20 feet to the power line, the employer must ensure that a dedicated spotter who is in continuous contact with the driver/operator is used. The dedicated spotter must:
When traveling at night, or in conditions of poor visibility, in addition to the measures specified in paragraphs (b)(1) through (4) of this section, the employer must ensure that:
| Voltage (nominal, kV, alternating current) | While traveling—minimum clearance distance (feet) |
|---|---|
| up to 0.75 | 4 |
| over .75 to 50 | 6 |
| over 50 to 345 | 10 |
| over 345 to 750 | 16 |
| Over 750 to 1,000 | 20 |
| Over 1,000 | (as established by the utility owner/operator or registered professional engineer who is a qualified person with respect to electrical power transmission and distribution). |
Deformed, cracked, or significantly corroded.
Unusual noises or vibration, low operating speed, excessive heating of the fluid, low pressure.
Sticking, improper return to neutral, and leaks.
Failure to reach correct pressure (if there is a manufacturer procedure for checking pressure, it must be followed).
Loose or deformed.
Missing.
Unserviceable.
The following information must be documented, maintained, and retained for a minimum of 12 months, by the employer that conducts the inspection:
Where the severity of use/conditions is such that there is a reasonable probability of damage or excessive wear (such as loading that may have exceeded rated capacity, shock loading that may have exceeded rated capacity, prolonged exposure to a corrosive atmosphere), the employer must stop using the equipment and a qualified person must:
Equipment that has been idle for 3 months or more must be inspected by a qualified person in accordance with the requirements of paragraph (e) (Monthly) of this section before initial use.
Apparent deficiencies in this category include the following:
Apparent deficiencies in this category are:
Six randomly distributed broken wires in one rope lay or three broken wires in one strand in one rope lay, where a rope lay is the length along the rope in which one strand makes a complete revolution around the rope.
Two randomly distributed broken wires in six rope diameters or four randomly distributed broken wires in 30 rope diameters.
More than two broken wires in one rope lay located in rope beyond end connections and/or more than one broken wire in a rope lay located at an end connection.
Apparent deficiencies in this category include the following:
The competent person must give particular attention to all of the following:
In the event an inspection under paragraph (c)(2) of this section is not feasible due to existing set-up and configuration of the equipment (such as where an assist crane is needed) or due to site conditions (such as a dense urban setting), such inspections must be conducted as soon as it becomes feasible, but no longer than an additional 6 months for running ropes and, for standing ropes, at the time of disassembly.
Wire rope (other than rotation resistant rope) must comply with either Option (1) or Option (2) of this section, as follows:
Wire rope must comply with section 5-1.7.1 of ASME B30.5-2004 (incorporated by reference, see § 1926.6) except that section's paragraph (c) must not apply.
Wire rope must be designed to have, in relation to the equipment's rated capacity, a sufficient minimum breaking force and design factor so that compliance with the applicable inspection provisions in § 1926.1413 will be an effective means of preventing sudden rope failure.
Type I rotation resistant rope is stranded rope constructed to have little or no tendency to rotate or, if guided, transmits little or no torque. It has at least 15 outer strands and comprises an assembly of at least three layers of strands laid helically over a center in two operations. The direction of lay of the outer strands is opposite to that of the underlying layer.
Type II rotation resistant rope is stranded rope constructed to have significant resistance to rotation. It has at least 10 outer strands and comprises an assembly of two or more layers of strands laid helically over a center in two or three operations. The direction of lay of the outer strands is opposite to that of the underlying layer.
Type III rotation resistant rope is stranded rope constructed to have limited resistance to rotation. It has no more than nine outer strands, and comprises an assembly of two layers of strands laid helically over a center in two operations. The direction of lay of the outer strands is opposite to that of the underlying layer.
The following safety devices are required on all equipment covered by this subpart, unless otherwise specified:
Operations must not begin unless all of the devices listed in this section are in proper working order. If a device stops working properly during operations, the operator must safely stop operations. If any of the devices listed in this section are not in proper working order, the equipment must be taken out of service and operations must not resume until the device is again working properly. See § 1926.1417 (Operation). Alternative measures are not permitted to be used.
Operational aids listed in this paragraph that are not working properly must be repaired no later than 7 calendar days after the deficiency occurs. Exception: If the employer documents that it has ordered the necessary parts within 7 calendar days of the occurrence of the deficiency, the repair must be completed within 7 calendar days of receipt of the parts. See § 1926.1417(j) for additional requirements.
Equipment with a luffing jib must have a luffing jib limiting device. Temporary alternative measures are the same as in paragraph (d)(1)(i) of this section, except to limit the movement of the luffing jib rather than the boom hoist.
Temporary alternative measures: Clearly mark the cable (so that it can easily be seen by the operator) at a point that will give the operator sufficient time to stop the hoist to prevent two-blocking, and use a spotter when extending the boom.
The requirements in paragraphs (d)(3)(ii)(A) and (B) of this section do not apply to such lattice boom equipment when used for dragline, clamshell (grapple), magnet, drop ball, container handling, concrete bucket, marine operations that do not involve hoisting personnel, and pile driving work.
Clearly mark the cable (so that it can easily be seen by the operator) at a point that will give the operator sufficient time to stop the hoist to prevent two-blocking, or use a spotter.
Operational aids listed in this paragraph that are not working properly must be repaired no later than 30 calendar days after the deficiency occurs. Exception: If the employer documents that it has ordered the necessary parts within 7 calendar days of the occurrence of the deficiency, and the part is not received in time to complete the repair in 30 calendar days, the repair must be completed within 7 calendar days of receipt of the parts. See § 1926.1417(j) for additional requirements.
The equipment must have a boom angle or radius indicator readable from the operator's station. Temporary alternative measures: Radii or boom angle must be determined by measuring the radii or boom angle with a measuring device.
Where the employer has taken the equipment out of service, a tag must be placed in the cab stating that the equipment is out of service and is not to be used. Where the employer has taken a function(s) out of service, a tag must be placed in a conspicuous position stating that the function is out of service and is not to be used.
When a local storm warning has been issued, the competent person must determine whether it is necessary to implement manufacturer recommendations for securing the equipment.
The operator must verify that the load is within the rated capacity of the equipment by at least one of the following methods:
A locomotive crane must not be swung into a position where railway cars on an adjacent track could strike it, until it is determined that cars are not being moved on the adjacent track and that proper flag protection has been established.
Whenever there is a concern as to safety, the operator must have the authority to stop and refuse to handle loads until a qualified person has determined that safety has been assured.
Signals to operators must be by hand, voice, audible, or new signals.
When using non-standard hand signals, the signal person, operator, and lift director (where there is one) must contact each other prior to the operation and agree on the non-standard hand signals that will be used.
Signals other than hand, voice, or audible signals may be used where the employer demonstrates that:
The signals used (hand, voice, audible, or new), and means of transmitting the signals to the operator (such as direct line of sight, video, radio, etc. ), must be appropriate for the site conditions.
Where a signal person(s) is in communication with more than one crane/derrick, a system must be used for identifying the crane/derrick each signal is for, as follows:
Hand signal charts must be either posted on the equipment or conspicuously posted in the vicinity of the hoisting operations.
Personal fall arrest system components must be used in personal fall arrest and fall restraint systems and must conform to the criteria in § 1926.502(d) except that § 1926.502(d)(15) does not apply to components used in personal fall arrest and fall restraint systems. Either body belts or body harnesses must be used in personal fall arrest and fall restraint systems.
Fall restraint systems must be anchored to any part of the equipment that is capable of withstanding twice the maximum load that an employee may impose on it during reasonably anticipated conditions of use.
A personal fall arrest system is permitted to be anchored to the crane/derrick's hook (or other part of the load line) where all of the following requirements are met:
The employer must train each employee who may be exposed to fall hazards while on, or hoisted by, equipment covered by this subpart on all of the following:
Only employees needed to receive a load are permitted to be within the fall zone when a load is being landed.
Where the use of equipment with a boom that is designed to free fall (live boom) is prohibited, the boom hoist must have a secondary mechanism or device designed to prevent the boom from falling in the event the primary system used to hold or regulate the boom hoist fails, as follows:
Hydraulic telescoping booms must have an integrally mounted holding device to prevent the boom from retracting in the event of hydraulic failure.
In each of the following circumstances, controlled load lowering is required and free fall of the load line hoist is prohibited:
The employer must ensure that each operator is trained, certified/licensed, and evaluated in accordance with this section before operating any equipment covered under subpart CC, except for the equipment listed in paragraph (a)(2) of this section.
An employee who has not been certified/licensed and evaluated to operate assigned equipment in accordance with this section may only operate the equipment as an operator-in-training under supervision in accordance with the requirements of paragraph (b) of this section.
Operators of derricks (see § 1926.1436), sideboom cranes (see § 1926.1440), or equipment with a maximum manufacturer-rated hoisting/lifting capacity of 2,000 pounds or less (see § 1926.1441) are not required to comply with § 1926.1427. Note: The training requirements in those other sections continue to apply (for the training requirement for operators of sideboom cranes, follow section 1926.1430(c)).
military.
Such a qualification meets the requirements of paragraph (a) of this section only where the operator is employed by (and operating the equipment for) the employer that issued the qualification.
The employer must provide each operator-in-training with sufficient training, through a combination of formal and practical instruction, to ensure that the operator-in-training develops the skills, knowledge, and ability to recognize and avert risk necessary to operate the equipment safely for assigned work.
The operator's trainer and the operator-in-training must be in direct line of sight of each other. In addition, they must communicate verbally or by hand signals. For tower cranes: The operator's trainer and the operator-in-training must be in direct communication with each other.
The employer must provide retraining in relevant topics for each operator when, based on the performance of the operator or an evaluation of the operator's knowledge, there is an indication that retraining is necessary.
The employer must ensure that each operator is certified or licensed to operate the equipment as follows:
When a state or local government issues operator licenses for equipment covered under subpart CC, the equipment operator must be licensed by that government entity for operation of equipment within that entity's jurisdiction if that government licensing program meets the following requirements:
When an operator is not required to be licensed under paragraph (c)(1) of this section, the operator must be certified in accordance with paragraph (d) or (e) of this section.
Whenever operator certification/licensure is required under this section, the employer must provide the certification/licensure at no cost to employees.
A testing entity is permitted to provide training as well as testing services as long as the criteria of the applicable governmental or accrediting agency (in the option selected) for an organization providing both services are met.
The employer's certification of its employee must meet the following requirements:
The written and practical tests must be either:
The employer program must be audited within 3 months of the beginning of the program and at least every 3 years thereafter.
The employer program must have testing procedures for re-qualification designed to ensure that the operator continues to meet the technical knowledge and skills requirements in paragraphs (j)(1) and (2) of this section. The re-qualification procedures must be audited in accordance with paragraphs (e)(1) and (2) of this section.
If the auditor determines that there is a significant deficiency (“deficiency”) in the program, the employer must ensure that:
A certification under this paragraph is:
Such a certification meets the requirements of paragraph (c) of this section only where the operator is employed by (and operating the equipment for) the employer that issued the certification.
Certifications must be based on the following:
[83 FR 56244, Nov. 9, 2018]
The signal person has documentation from a third party qualified evaluator ( see Qualified Evaluator (third party), § 1926.1401 for definition) showing that the signal person meets the Qualification Requirements ( see paragraph (c) of this section).
The employer's qualified ( see Qualified Evaluator (not a third party), § 1926.1401 for definition) evaluator assesses the individual and determines that the individual meets the Qualification Requirements ( see paragraph (c) of this section) and provides documentation of that determination. An assessment by an employer's qualified evaluator under this option is not portable—other employers are not permitted to use it to meet the requirements of this section.
Each signal person must:
If hand signals are used, the signal person must know and understand the Standard Method for hand signals.
The employer must provide training as follows:
The employer must train each employee specified in § 1926.1408(g) and § 1926.1410(m) in the topics listed in § 1926.1408(g).
The employer must train each employee who will be assigned to work as a signal persons who does not meet the requirements of § 1926.1428(c) in the areas addressed in that paragraph.
The employer must train each competent person and each qualified person regarding the requirements of this subpart applicable to their respective roles.
The employer must train each employee who works with the equipment to keep clear of holes, and crush/pinch points and the hazards addressed in § 1926.1424 (Work area control).
The employer must train each operator and each additional employee authorized to start/energize equipment or operate equipment controls (such as maintenance and repair employees), in the tag-out and start-up procedures in §§ 1926.1417(f) and (g).
[75 FR 48135, Aug. 9, 2010, as amended at 83 FR 56247, Nov. 9, 2018]
The requirements of this section are supplemental to the other requirements in this subpart and apply when one or more employees are hoisted.
A personnel platform is not required for hoisting employees:
Use of suspended personnel platforms. The total load (with the platform loaded, including the hook, load line and rigging) must not exceed 50 percent of the rated capacity for the radius and configuration of the equipment, except during proof testing.
Use of boom-attached personnel platforms. The total weight of the loaded personnel platform must not exceed 50 percent of the rated capacity for the radius and configuration of the equipment (except during proof testing).
Hoisting personnel without a personnel platform. When hoisting personnel without a personnel platform pursuant to paragraph (b)(2) of this section, the total load (including the hook, load line, rigging and any other equipment that imposes a load) must not exceed 50 percent of the rated capacity for the radius and configuration of the equipment, except during proof testing.
A device which automatically prevents damage and load failure from contact between the load block, overhaul ball, or similar component, and the boom tip (or fixed upper block or similar component) must be used. The device(s) must prevent such damage/failure at all points where two-blocking could occur. Exception: This device is not required when hoisting personnel in pile driving operations. Instead, paragraph (p)(2) of this section specifies how to prevent two-blocking during such operations.
The load line hoist drum must have a system, other than the load line hoist brake, which regulates the lowering rate of speed of the hoist mechanism. This system or device must be used when hoisting personnel.
Personnel hoisting operations must not begin unless the devices listed in this section are in proper working order. If a device stops working properly during such operations, the operator must safely stop operations. Personnel hoisting operations must not resume until the device is again working properly. Alternative measures are not permitted. ( See § 1926.1417 for tag-out and related requirements.)
If installed, access gates/doors of all types (including swinging, sliding, folding, or other types) must:
If due to the size of the personnel platform, such as a 1-person platform, it is infeasible for the door to swing inward and allow safe entry for the platform occupant, then the access gate/door may swing outward.
Materials and tools to be used during the lift, if secured and distributed in accordance with paragraph (f)(3) of this section may be in the platform for trial lifts.
When a rope bridle is used to suspend the personnel platform, each bridle leg must be connected to a master link or shackle ( see paragraph (g)(1) of this section) in a manner that ensures that the load is evenly divided among the bridle legs.
Where the platform is not equipped with controls, the equipment operator must remain at the equipment controls, on site, and in view of the equipment, at all times while the platform is occupied.
Where the platform is equipped with controls, all of the following must be met at all times while the platform is occupied:
When wind speed (sustained or gusts) exceeds 20 mph at the personnel platform, a qualified person must determine if, in light of the wind conditions, it is not safe to lift personnel. If it is not, the lifting operation must not begin (or, if already in progress, must be terminated).
A qualified person must determine if, in light of indications of dangerous weather conditions, or other impending or existing danger, it is not safe to lift personnel. If it is not, the lifting operation must not begin (or, if already in progress, must be terminated).
Derricks are prohibited from traveling while personnel are hoisted.
A pre-lift meeting must be:
Hoisting personnel within 20 feet of a power line that is up to 350 kV, and hoisting personnel within 50 feet of a power line that is over 350 kV, is prohibited, except for work covered by subpart V of this part (Power Transmission and Distribution).
When hoisting employees into and out of drill shafts that are up to and including 8 feet in diameter, all of the following requirements must be met:
When hoisting an employee in pile driving operations, the following requirements must be met:
Clearly mark the cable (so that it can easily be seen by the operator) at a point that will give the operator sufficient time to stop the hoist to prevent two-blocking, or use a spotter who is in direct communication with the operator to inform the operator when this point is reached. For telescopic boom cranes: Clearly mark the cable (so that it can be easily seen by the operator) at a point that will give the operator sufficient time to stop the hoist to prevent two-blocking, and use a spotter who is in direct communication with the operator to inform the operator when this point is reached.
When hoisting employees solely for transfer to or from a marine worksite, the following requirements must be met:
[75 FR 48135, Aug. 9, 2010, as amended at 85 FR 8746, Feb. 18, 2020]
Before beginning a crane/derrick operation in which more than one crane/derrick will be supporting the load, the operation must be planned. The planning must meet the following requirements:
The following requirements apply to equipment that has a manufacturer-rated hoisting/lifting capacity of more than 2,000 pounds.
mobile (including crawler and truck) and locomotive cranes manufactured on or after November 8, 2010 must meet the prototype testing requirements in Test Option A or Test Option B of this section. Tower cranes manufactured on or after November 8, 2010 must meet the prototype testing requirements in BS EN 14439:2006 (incorporated by reference, see § 1926.6).
The testing and verification requirements of BS EN 13000:2004 (incorporated by reference, see § 1926.6) must be met. In applying BS EN 13000:2004, the following additional requirements must be met:
The physical testing requirements under SAE J1063 (Nov. 1993) (incorporated by reference, see § 1926.6) and SAE J987 (Jun. 2003) (incorporated by reference, see § 1926.6) must be met unless the reliability of the analysis methodology (computer modeling) has been demonstrated by a documented history of verification through strain gauge measuring or strain gauge measuring in combination with other physical testing.
The information available in the cab ( see § 1926.1417(c)) regarding “rated capacity” and related information must include, at a minimum, the following information:
Posted warnings required by this subpart as well as those originally supplied with the equipment by the manufacturer must be maintained in legible condition.
Equipment with cabs must meet the following requirements:
Where friction mechanisms (such as brakes and clutches) are used to control the boom hoist or load line hoist, they must be:
Hydraulic drums must have an integrally mounted holding device or internal static brake to prevent load hoist movement in the event of hydraulic failure.
The manufacturer is provided a detailed description of the proposed modification/addition, is asked to approve the modification/addition, but it declines to review the technical merits of the proposal or fails, within 30 days, to acknowledge the request or initiate the review, and all of the following are met:
The manufacturer is unavailable and the requirements of paragraphs (a)(2)(i) and (ii) of this section are met.
In addition to the requirements in § 1926.1404(e), for self-erecting tower cranes, the following applies: Employees must not be in or under the tower, jib, or rotating portion of the crane during erecting, climbing and dismantling operations until the crane is secured in a locked position and the competent person in charge indicates it is safe to enter this area, unless the manufacturer's instructions direct otherwise and only the necessary personnel are permitted in this area.
Tower crane foundations and structural supports (including both the portions of the structure used for support and the means of attachment) must be designed by the manufacturer or a registered professional engineer.
The requirements in § 1926.1404(h)(1) through (9) apply. In addition, the A/D director must address the following:
The A/D director must determine that tower crane foundations and structural supports are installed in accordance with their design.
Backward stability before swinging self erecting cranes or cranes on traveling or static undercarriages.
Wind must not exceed the speed recommended by the manufacturer or, where manufacturer does not specify this information, the speed determined by a qualified person.
Towers must be erected plumb to the manufacturer's tolerance and verified by a qualified person. Where the manufacturer does not specify plumb tolerance, the crane tower must be plumb to a tolerance of at least 1:500 (approximately 1 inch in 40 feet).
On jobsites where more than one fixed jib (hammerhead) tower crane is installed, the cranes must be located such that no crane can come in contact with the structure of another crane. Cranes are permitted to pass over one another.
Prior to, and during, all climbing procedures (including inside climbing and top climbing), the employer must:
The size and location of signs installed on tower cranes must be in accordance with manufacturer specifications. Where these are unavailable, a registered professional engineer familiar with the type of equipment involved must approve in writing the size and location of any signs.
Operations must not begin unless the devices listed in this section are in proper working order. If a device stops working properly during operations, the operator must safely stop operations. The equipment must be taken out of service, and operations must not resume until the device is again working properly. See § 1926.1417(f). Alternative measures are not permitted to be used.
Operational aids listed in this paragraph that are not working properly must be repaired no later than 7 calendar days after the deficiency occurs. Exception: If the employer documents that it has ordered the necessary parts within 7 calendar days of the occurrence of the deficiency, the repair must be completed within 7 calendar days of receipt of the parts.
The travel of the trolley must be restricted at both ends of the jib by a trolley travel limiting device to prevent the trolley from running into the trolley end stops. Temporary alternative measures:
The trolley rope must be marked (so it can be seen by the operator) at a point that will give the operator sufficient time to stop the trolley prior to the end stops.
A spotter who is in direct communication with the operator must be used when operations are conducted within 10 feet of the outer or inner trolley end stops.
The range of the boom must be limited at the minimum and maximum radius. Temporary alternative measures: Clearly mark the cable (so it can be seen by the operator) at a point that will give the operator sufficient time to stop the boom hoist within the minimum and maximum boom radius, or use a spotter who is in direct communication with the operator to inform the operator when this point is reached.
The tower crane must be equipped with a device which automatically prevents damage from contact between the load block, overhaul ball, or similar component, and the boom tip (or fixed upper block or similar component). The device(s) must prevent such damage at all points where two-blocking could occur. Temporary alternative measures: Clearly mark the cable (so it can be seen by the operator) at a point that will give the operator sufficient time to stop the hoist to prevent two-blocking, or use a spotter who is in direct communication with the operator to inform the operator when this point is reached.
Tower cranes manufactured after November 8, 2011 must be equipped with a device that prevents the last 2 wraps of hoist cable from being spooled off the drum. Temporary alternative measures: Mark the cable (so it can be seen by the operator) at a point that will give the operator sufficient time to stop the hoist prior to last 2 wraps of hoist cable being spooled off the drum, or use a spotter who is in direct communication with the operator to inform the operator when this point is reached
The tower crane must have a device that prevents moment overloading. Temporary alternative measures: A radius indicating device must be used (if the tower crane is not equipped with a radius indicating device, the radius must be measured to ensure the load is within the rated capacity of the crane). In addition, the weight of the load must be determined from a source recognized by the industry (such as the load's manufacturer), or by a calculation method recognized by the industry (such as calculating a steel beam from measured dimensions and a known per foot weight), or by other equally reliable means. This information must be provided to the operator prior to the lift.
The capacity of the hoist must be limited to prevent overloading, including each individual gear ratio if equipped with a multiple speed hoist transmission. Temporary alternative measures: The operator must ensure that the weight of the load does not exceed the capacity of the hoist (including for each individual gear ratio if equipped with a multiple speed hoist transmission).
The travel distance in each direction must be limited to prevent the travel bogies from running into the end stops or buffers. Temporary alternative measures: A spotter who is in direct communication with the operator must be used when operations are conducted within 10 feet of either end of the travel rail end stops; the spotter must inform the operator of the distance of the travel bogies from the end stops or buffers.
The boom hoist drum must be equipped with a control that will enable the operator to positively lock the boom hoist drum from the cab. Temporary alternative measures: The device must be manually set when required if an electric, hydraulic or automatic control is not functioning.
Operational aids listed in this paragraph that are not working properly must be repaired no later than 30 calendar days after the deficiency occurs. Exception: If the employer documents that it has ordered the necessary parts within 7 calendar days of the occurrence of the deficiency, and the part is not received in time to complete the repair in 30 calendar days, the repair must be completed within 7 calendar days of receipt of the parts.
Hook radii or boom angle must be determined by measuring the hook radii or boom angle with a measuring device.
The trolley speed must be automatically reduced prior to the trolley reaching the end limit in both directions. Temporary alternative measure: The employer must post a notice in the cab of the crane notifying the operator that the trolley travel deceleration device is malfunctioning and instructing the operator to take special care to reduce the trolley speed when approaching the trolley end limits.
The boom speed must be automatically reduced prior to the boom reaching the minimum or maximum radius limit. Temporary alternative measure: The employer must post a notice in the cab of the crane notifying the operator that the boom hoist deceleration device is malfunctioning and instructing the operator to take special care to reduce the boom speed when approaching the minimum or maximum radius limits.
The load speed must be automatically reduced prior to the hoist reaching the upper limit. Temporary alternative measure: The employer must post a notice in the cab of the crane notifying the operator that the load hoist deceleration device is malfunctioning and instructing the operator to take special care to reduce the load speed when approaching the upper limits.
A device must be provided to display the wind speed and must be mounted above the upper rotating structure on tower cranes. On self erecting cranes, it must be mounted at or above the jib level. Temporary alternative measures: Use of wind speed information from a properly functioning indicating device on another tower crane on the same site, or a qualified person estimates the wind speed.
Cranes manufactured after November 8, 2011 must have a device that displays the magnitude of the load on the hook. Displays that are part of load moment limiting devices that display the load on the hook meet this requirement. Temporary alternative measures: The weight of the load must be determined from a source recognized by the industry (such as the load's manufacturer), or by a calculation method recognized by the industry (such as calculating a steel beam from measured dimensions and a known per foot weight), or by other equally reliable means. This information must be provided to the operator prior to the lift.
Before each crane component is erected, it must be inspected by a qualified person for damage or excessive wear.
In addition to the requirements in § 1926.1412(c), the following requirements must be met:
The following additional items must be included:
In addition to the items that must be inspected under § 1926.1412(f), all turntable and tower bolts must be inspected for proper condition and torque.
Load charts must contain at least the following information:
For permanently installed derricks with fixed lengths of boom, guy, and mast, a load chart must be posted where it is visible to personnel responsible for the operation of the equipment.
For derricks that are not permanently installed, the load chart must be readily available at the job site to personnel responsible for the operation of the equipment.
The fittings for stepping the boom and for attaching the topping lift must be arranged to:
The employer must ensure that new hoists are load tested to a minimum of 110% of rated capacity, but not more than 125% of rated capacity, unless otherwise recommended by the manufacturer. This requirement is met where the manufacturer has conducted this testing.
Hoists that have had repairs, modifications or additions affecting their capacity or safe operation must be evaluated by a qualified person to determine if a load test is necessary. If it is, load testing must be conducted in accordance with paragraphs (e)(2)(ii) and (iv) of this section.
Load tests required by paragraphs (e)(2)(ii) or (e)(2)(iii) of this section must be conducted as follows:
A boom angle indicator is not required but if the derrick is not equipped with a functioning one, the employer must ensure that either:
Prior to initial use, new or reinstalled derricks must be tested by a competent person with no hook load to verify proper operation. This test must include:
Prior to initial use, new or reinstalled derricks must be load tested by a competent person. The test load must meet the following requirements:
Tests conducted under this paragraph must be documented. The document must contain the date, test results and the name of the tester. The document must be retained until the derrick is re-tested or dismantled, whichever occurs first. All such documents must be available, during the applicable document retention period, to all persons who conduct inspections in accordance with § 1926.1412.
Derricks that have had repairs, modifications or additions affecting the derrick's capacity or safe operation must be evaluated by a qualified person to determine if a load test is necessary. If it is, load testing must be conducted and documented in accordance with paragraph (g) of this section.
If power fails during operations, the derrick operator must safely stop operations. This must include:
In addition to the requirements in § 1926.1412, the following additional items must be included in the inspections:
Guys for proper tension.
The employer must train each operator of a derrick on the safe operation of equipment the individual will operate. Section 1926.1427 of this subpart (Operator qualification and certification) does not apply.
The requirements in paragraphs (c) through (k) of this section apply to both floating cranes/derricks and land cranes/derricks on barges, pontoons, vessels or other means of flotation.
Section 1926.1425 does not apply.
In addition to the safety devices listed in § 1926.1415, the following safety devices are required:
A competent person must determine if wind is a factor that needs to be considered; if wind needs to be considered, a wind speed and direction indicator must be used.
If the crane/derrick has a cab, the requirements of § 1926.1417(c) apply. If the crane/derrick does not have a cab, the employer must ensure that:
In addition to meeting the requirements of § 1926.1412 for inspecting the crane/derrick, the employer must inspect the barge, pontoons, vessel or other means of flotation used to support a floating crane/derrick or land crane/derrick, and ensure that:
For each shift inspection, the means used to secure/attach the equipment to the vessel/flotation device is in proper condition, including wear, corrosion, loose or missing fasteners, defective welds, and (when applicable) insufficient tension.
For each monthly inspection:
external vessel/flotation device inspection. For each annual inspection:
internal vessel/flotation device inspection. For each four-year inspection:
The monthly and annual inspections required in paragraphs (h)(2) and (h)(4) of this section are documented in accordance with §§ 1926.1412 (e)(3) and 1926.1412(f)(7), respectively, and that the four-year inspection required in paragraph (h)(5) of this section is documented in accordance with § 1926.1412(f)(7), except that the documentation for that inspection must be retained for a minimum of 4 years. All such documents must be made available, during the applicable document retention period, to all persons who conduct inspections in accordance with § 1926.1412.
The employer must meet the following additional requirements when working with a diver in the water:
For equipment designed by the manufacturer (or employer) for marine use by permanent attachment to barges, pontoons, vessels or other means of flotation:
| Rated capacity | Maximum allowable list (degrees) | Maximum allowable trim (degrees) |
|---|---|---|
| Equipment designed for marine use by permanent attachment (other than derricks): | ||
| 25 tons or less | 5 | 5 |
| Over 25 tons | 7 | 7 |
| Derricks designed for marine use by permanent attachment: | ||
| Any rated capacity | 10 | 10 |
| Operated at | Wind speed (mph) | Minimum freeboard (ft) |
|---|---|---|
| Rated capacity | 60 | 2 |
| Rated capacity plus 25% | 60 | 1 |
| High boom, no load | 60 | 2 |
| Operated at | Wind speed |
|---|---|
| For backward stability of the boom: | |
| High boom, no load, full back list (least stable condition) | 90 mph. |
For land cranes/derricks used on barges, pontoons, vessels or other means of flotation, the employer must ensure that:
The crane/derrick is physically attached to the barge, pontoons, vessel or other means of flotation. Methods of physical attachment include crossed-cable systems attached to the crane/derrick and vessel/flotation device, bolting or welding the crane/derrick to the vessel/flotation device, strapping the crane/derrick to the vessel/flotation device with chains, or other methods of physical attachment.
The crane/derrick is prevented from shifting by installing barricade restraints ( i.e., a corralling system). Employers must ensure that corralling systems do not allow the equipment to shift by any amount of shifting in any direction.
The crane/derrick must be prevented from shifting by being mounted on a rail system. Employers must ensure that rail clamps and rail stops are used unless the system is designed to prevent movement during operation by other means.
The crane/derrick is prevented from shifting by being mounted to a wire rope system. The employer must ensure that the wire rope system meets the following requirements:
For mobile auxiliary cranes used on the deck of a floating crane/derrick, the requirement specified by paragraph (n)(5) of this section to use Option (1), Option (2), Option (3), or Option (4) does not apply when the employer demonstrates implementation of a plan and procedures that meet the following requirements:
The requirements of § 1910.179, except for § 1910.179(b)(1), and not the requirements of this subpart CC, apply to the following equipment when used in construction and permanently installed in a facility: overhead and gantry cranes, including semigantry, cantilever gantry, wall cranes, storage bridge cranes, and others having the same fundamental characteristics.
The following paragraphs of this section specify requirements for employers using equipment with a maximum rated hoisting/lifting capacity of 2,000 pounds or less.
The employer must ensure that:
Upon completion of assembly, the equipment is inspected to ensure that it is in compliance with paragraph (b)(2)(i) of this section ( see § 1926.1412(c) for post-assembly inspection requirements).
The employer must comply with applicable manufacturer prohibitions.
The employer must:
The employer must ensure that:
The employer must ensure that equipment covered by this section manufactured more than one year after November 8, 2010 have either an anti two-block device that meets the requirements of § 1926.1416(d)(3), or is designed so that, in the event of a two-block situation, no damage or load failure will occur (for example, by using a power unit that stalls in response to a two-block situation).
The employer must train each operator, prior to operating the equipment, on the safe operation of the type of equipment the operator will be using.
The employer must train each signal person in the proper use of signals applicable to the use of the equipment.
The employer must ensure that equipment is inspected in accordance with manufacturer procedures.
The employer must ensure that equipment covered by this section is not used to hoist personnel.
The employer must ensure that the equipment is designed by a qualified engineer.
Employers using equipment covered by this subpart that meets the definition of “roadway maintenance machine,” as defined in 49 CFR 214.7, must comply with the requirements in this subpart, except as provided in paragraphs (b)(1) through (7) of this section when subject to the authority of the Federal Railroad Administration.
The restrictions on out-of-level work, and the requirements for crane-level indicators and inspections of those indicators (including the requirements in §§ 1926.1402(b), 1926.1412(d)(1)(xi), and 1926.1415(a)(1)), do not apply.
The prohibition in § 1926.1417(q) on dragging a load sideways does not apply.
The requirement in § 1926.1416(d)(1) for a boom-hoist limiting device does not apply to roadway maintenance machines when the cranes use hydraulic cylinders to raise the booms.
The requirements to follow the manufacturer's guidance set forth in § 1926.1434 do not apply if the employer is subject to the requirements of 49 CFR part 214.
The requirements to follow the manufacturer's guidance, instructions, procedures, prohibitions, limitations, or specifications, set forth in § 1926.1404(j), (m), or (q); § 1926.1415(a)(6); § 1926.1417(a), (r), (u), or (aa); § 1926.1433(d)(1)(i); or § 1926.1441 do not apply if the employer is subject to the requirements of 49 CFR part 214.
[85 FR 57122, Sept. 15, 2020]
Should a court of competent jurisdiction hold any provision(s) of subpart CC to be invalid, such action shall not affect any other provision of the subpart.
[75 FR 48135, Aug. 9, 2010. Redesignated at 85 FR 57122, Sept. 15, 2020]
1. Section 1926.1404(f)(1) provides that when pins (or similar devices) are being removed, employees must not be under the boom, jib, or other components, except where the requirements of § 1926.1404(f)(2) are met. The exception in § 1926.1404(f)(2) applies when the employer demonstrates that site constraints require one or more employees to be under the boom, jib, or other components when pins (or similar devices) are being removed. In such a situation, the A/D director must implement procedures that minimize the risk of unintended dangerous movement and minimize the duration and extent of exposure under the boom.
The following scenario is an example of how the exception applies: A boom cannot be disassembled on the ground because of aboveground piping (as might be found, for example, in an oil refinery) that precludes lowering the boom to the ground. The boom must therefore be disassembled in the air, and the employees who remove the pins must perform that work from an aerial lift whose base is positioned on one side (the near side) of the boom. To gain access to the pins on the far side, the aerial lift basket must move under the boom, since, due to lack of room, the aerial lift cannot be repositioned on the far side. Due to lack of room, the aerial lift cannot be repositioned on the far side, so the aerial basket must move under the boom to gain access to the pins on the far side.
To minimize the risk of unintended dangerous movement while the pins are removed, the A/D director uses an assist crane that is rigged to support the boom section that is being detached, using particular care to ensure that the section end that is near the employee(s) removing the pins is well supported. The duration and extent of exposure is minimized by removing the far side pins first, moving the aerial lift basket as soon as possible to the near side so that the employees are no longer under the boom, and then removing the near side pins.
2. Section 1926.1404(h)(6)(i) provides that, during assembly/disassembly, the center of gravity of the load must be identified if that is necessary for the method used for maintaining stability. Section 1926.1404(h)(6)(ii) states that, where there is insufficient information to accurately identify the center of gravity, measures designed to prevent unintended dangerous movement resulting from an inaccurate identification of the center of gravity must be used.
An example of the application of § 1926.1404(h)(6)(ii) is as follows: The boom is assembled by lowering boom sections sequentially into place using an assist crane. The A/D director's plan is to keep the boom sections stable while they are lowered into place by attaching the assist crane hoist line above the center of gravity of each section. However, in assembling the non-symmetrical top section of the boom, the A/D director is not able to determine where to attach the assist crane hoist line so that it is above the center of gravity. In this situation, before raising the section, all personnel are kept clear of the section and the section is first raised a few inches to determine whether it tips when raised (if it did tip, it would indicate it is not rigged over the center of gravity). If this occurs, the hoist line is repositioned and the procedure repeated (with employees kept clear of the section while it is raised) until the A/D director determines that it is rigged over the center of gravity and can be moved into place without dangerous movement.
This appendix contains information for employers, accredited testing organizations, auditors and government entities developing criteria for a written examination to test an individual's technical knowledge relating to the operation of cranes.
This includes knowing:
New Designations for General Industry Standards Incorporated Into Body of Construction Standards
| New § no. and/or para. | Source § no. and/or para. |
|---|---|
| 1926.20 (c) | 1910.5 (a) |
| [Do.] (d) | [Do.] (c) |
| [Do.] (e) | [Do.] (d) |
| 1926.32(g) | 1910.12(b) |
| 1926.33 | 1910.20 |
| 1926.34 (a) | 1910.36(b)(4) |
| [Do.] (b) | 1910.37 (q)(1) |
| [Do.] (c) | [Do.] (k)(2) |
| 1926.35 | 1910.38(a) |
| 1926.50(g) | 1910.151(c) |
| 1926.51(a)(6) | 1910.141(a)(2)(v) |
| [Do.] (d)(2) | [Do.] (h) |
| [Do.] (f) (2)-(4) | [Do.] (d) (1)-(3) |
| [Do.] (g) | [Do.] (g)(2) |
| [Do.] (h) | [Do.] (a)(5) |
| [Do.] (i) | [Do.] (e) |
| 1926.53 (c)-(r) | 1910.96 |
| 1926.57 (f)-(i) | 1910.94 |
| 1926.64 | 1910.119 |
| 1926.65 | 1910.120 |
| 1926.66 (a) | 1910.107 (a) |
| [Do.] (b) | [Do.] (b) (1)-(10) |
| [Do.] (c)-(d) | [Do.] (c)-(d) |
| [Do.] (e)-(g) | [Do.] (h)-(j) |
| 1926.95 | 1910.132 |
| 1926.96 | 1910.136 |
| 1926.97 (a)-(e) | 1910.156(e) |
| [Do.] (f)-(h) | [Do.] Subpt. L App. E |
| 1926.98 | 1910.156(f) |
| 1926.102(a) (6) | 1910.133(a) (2) |
| [Do.] (7) | [Do.] (4) |
| [Do.] (8) | [Do.] (5) |
| 1926.103 (d) | 1910.134 (a) |
| [Do.] (e) | [Do.] (b) |
| [Do.] (f)-(i) | [Do.] (d)-(g) |
| 1926.150(c)(1) (xi) | 1910.157 (g)(1) |
| [Do.] (xii) | [Do.] (g)(2) |
| [Do.] (xiii) | [Do.] (c)(4) |
| [Do.] (xiv) | [Do.] (e)(3) |
| 1926.152 (b)(5) | 1910.107(e)(2) |
| [Do.] (h) | 1910.106(j) |
| [Do.] (i) | [Do.] (b) |
| [Do.] (j) | [Do.] (c) |
| [Do.] (k) (1)-(3) | [Do.] (g)(4) |
| [Do.] (k)(4) | [Do.] (a)(22) |
| 1926.153(a) (3) | 1910.110(a)(4) |
| [Do.] (m) (1) | [Do.] (d)(1) |
| [Do.] (2) | [Do.] (d)(2) |
| [Do.] (3) | [Do.] (d)(7)(vii) |
| [Do.] (4) | [Do.] (d)(7)(viii) |
| [Do.] (n) | [Do.] (b)(5)(iii) |
| [Do.] (o) | [Do.] (d)(10) |
| 1926.156 | 1910.160 |
| 1926.157 | 1910.162 |
| 1926.158 | 1910.164 |
| 1926.159 | 1910.165 |
| 1926.200(c)(3) | 1910.145(d)(4) |
| 1926.250(c) | 1910.176(c) |
| [Do.] (d) (1)-(4) | 1910.30(a) (1), (2), (4) and (5) |
| 1926.251(a)(5) | 1910.184(a) |
| [Do.] (a)(6) | [Do.] (d) |
| [Do.] (b)(6)(i)-(ii) | [Do.] (e)(3)(i)-(ii) |
| [Do.] (c)(6)-(7) | [Do.] (c) (2)-(3) |
| [Do.] (c)(8) | [Do.] (c)(5) |
| [Do.] (c)(9) | [Do.] (c)(7) |
| [Do.] (c)(10)-(12) | [Do.] (c)(10)-(12) |
| [Do.] (c)(13)-(15) | [Do.](f) (2)-(4) |
| [Do.] (d)(3)-(6) | [Do.] (h) (2)-(5) |
| [Do.] (e)(3)-(5) | [Do.] (i) (2)-(4) |
| [Do.] (e)(6)-(7) | [Do.] (i) (6)-(7) |
| [Do.] (e)(8) | [Do.] (i)(9) |
| 1926.300(b) (3) | 1910.212(a)(1) |
| [Do.] (4) | [Do.] (a)(3) |
| [Do.] (5) | [Do.] (a)(5) |
| [Do.] (6) | [Do.] (b) |
| [Do.] (7) | 1910.215(b)(9) |
| [Do.] (8) and (9) | [Do.] (b) (3) and (4) |
| 1926.302(b)(10) | 1910.244(b) |
| 1926.303(b)(2) | 1910.215(a) (2) |
| [Do.] (e) | [Do.] (4) |
| 1926.304 (g) | 1910.213(h)(1) |
| [Do.] (h) | [Do.] (d)(1) |
| [Do.] (i) | [Do.] (c)(1) |
| 1926.305(d)(1) | 1910.244(a)(2) (iii)-(viii) |
| 1926.306 | 1910.169 |
| 1926.307 | 1910.219 |
| 1926.350(a) (10) | 1910.253(b) (4)(iii) |
| [Do.] (11) | [Do.] (2)(ii) |
| [Do.] (12) | 1910.101(b) |
| 1926.353(b)(3) | 1910.252(b)(4)(iv) |
| 1926.416 (a)(4) | 1910.333(c)(2) |
| [Do.] (f) (1) | [Do.] (c)(10) |
| [Do.] (2) | 1910.334(a)(1) |
| [Do.] (3) | [Do.] (a)(2)(iii) |
| [Do.] (4) | [Do.] (a)(5) |
| [Do.] (5)-(6) | [Do.] (b) (1)-(2) |
| [Do.] (7)-(9) | [Do.] (c) (1)-(3) |
| [Do.] (10) | [Do.] (d) |
| 1926.417(d) | 1910.333(b)(2) |
| 1926.451(a) (22) | 1910.28(a) (15) |
| [Do.] (23) | [Do.] (18) |
| [Do.] (24) | [Do.] (20) |
| 1926.453 (a) | 1910.29(a) |
| [Do.] (b) | [Do.] (c) |
| 1926.600(a)(7) | 1910.176(f) |
| 1926.602(c)(1) (vii) | 1910.178(m) (3) |
| [Do.] (viii) | [Do.] (12) |
| 1926.900 (s) | 1910.109 (g)(2)(ii) |
| [Do.] (t) | [Do.] (h)(3)(ii) |
| 1926.905(u) | [Do.] (e)(3)(iii) |
| 1926.914(aa) | [Do.] (a)(12) |
| 1926.1050(b) | 1910.21(g)(9) |
| 1926.1071 | 1910.401 |
| 1926.1072 | 1910.402 |
| 1926.1076 | 1910.410 |
| 1926.1080 | 1910.420 |
| 1926.1081 | 1910.421 |
| 1926.1082 | 1910.422 |
| 1926.1083 | 1910.423 |
| 1926.1084 | 1910.424 |
| 1926.1085 | 1910.425 |
| 1926.1086 | 1910.426 |
| 1926.1087 | 1910.427 |
| 1926.1090 | 1910.430 |
| 1926.1091 | 1910.440 |
| 1926.1092 | 1910.441 |
| 1926.1102 | 1910.1002 |
| 1926.1103 | 1910.1003 |
| 1926.1104 | 1910.1004 |
| 1926.1105 | 1910.1005 |
| 1926.1106 | 1910.1006 |
| 1926.1107 | 1910.1007 |
| 1926.1108 | 1910.1008 |
| 1926.1109 | 1910.1009 |
| 1926.1110 | 1910.1010 |
| 1926.1111 | 1910.1011 |
| 1926.1112 | 1910.1012 |
| 1926.1113 | 1910.1013 |
| 1926.1114 | 1910.1014 |
| 1926.1115 | 1910.1015 |
| 1926.1116 | 1910.1016 |
| 1926.1117 | 1910.1017 |
| 1926.1118 | 1910.1018 |
| 1926.1128 | 1910.1028 |
| 1926.1129 | 1910.1029 |
| 1926.1144 | 1910.1044 |
| 1926.1145 | 1910.1045 |
| 1926.1147 | 1910.1047 |
| 1926.1148 | 1910.1048 |
[58 FR 35305, June 30, 1993, as amended at 61 FR 9255, Mar. 7, 1996; 75 FR 48135, Aug. 9, 2010]