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]
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.
[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]
[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.
Appendix C to Section 1903.19—Sample Warning Tag (Nonmandatory)
[62 FR 15337, Mar. 31, 1997]
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.
[66 FR 6122, Jan. 19, 2001, as amended at 81 FR 91809, Dec. 19, 2016; 82 FR 20548, May 3, 2017]
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).
[67 FR 44047, July 1, 2002, as amended at 67 FR 77170, Dec. 17, 2002; 84 FR 21457, May 14, 2019]
[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]
[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]
[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]
[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]
[66 FR 6122, Jan. 19, 2001, as amended at 80 FR 49904, Aug. 18, 2015]
[79 FR 56187, Sept. 18, 2014]
[66 FR 6122, Jan. 19, 2001, as amended at 81 FR 91810, Dec. 19, 2016; 82 FR 20549, May 3, 2017]
[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]
Appendix A to Subpart E of Part 1904—Designated Industries for § 1904.41(a)(1)(i) Annual Electronic Submission of Information From OSHA Form 300A Summary of Work-Related Injuries and Illnesses by Establishments With 20-249 Employees in Designated Industries NAICS Industry 11 Agriculture, Forestry, Fishing and Hunting. 22 Utilities. 23 Construction. 31-33 Manufacturing. 42 Wholesale Trade. 4413 Automotive Parts, Accessories, and Tire Stores. 4421 Furniture Stores. 4422 Home Furnishings Stores. 4441 Building Material and Supplies Dealers. 4442 Lawn and Garden Equipment and Supplies Stores. 4451 Grocery Stores. 4452 Specialty Food Stores. 4522 Department Stores. 4523 General Merchandise Stores, including Warehouse Clubs and Supercenters. 4533 Used Merchandise Stores. 4542 Vending Machine Operators. 4543 Direct Selling Establishments. 4811 Scheduled Air Transportation. 4841 General Freight Trucking. 4842 Specialized Freight Trucking. 4851 Urban Transit Systems. 4852 Interurban and Rural Bus Transportation. 4853 Taxi and Limousine Service. 4854 School and Employee Bus Transportation. 4855 Charter Bus Industry. 4859 Other Transit and Ground Passenger Transportation. 4871 Scenic and Sightseeing Transportation, Land. 4881 Support Activities for Air Transportation. 4882 Support Activities for Rail Transportation. 4883 Support Activities for Water Transportation. 4884 Support Activities for Road Transportation. 4889 Other Support Activities for Transportation. 4911 Postal Service. 4921 Couriers and Express Delivery Services. 4922 Local Messengers and Local Delivery. 4931 Warehousing and Storage. 5152 Cable and Other Subscription Programming. 5311 Lessors of Real Estate. 5321 Automotive Equipment Rental and Leasing. 5322 Consumer Goods Rental. 5323 General Rental Centers. 5617 Services to Buildings and Dwellings. 5621 Waste Collection. 5622 Waste Treatment and Disposal. 5629 Remediation and Other Waste Management Services. 6219 Other Ambulatory Health Care Services. 6221 General Medical and Surgical Hospitals. 6222 Psychiatric and Substance Abuse Hospitals. 6223 Specialty (except Psychiatric and Substance Abuse) Hospitals. 6231 Nursing Care Facilities (Skilled Nursing Facilities). 6232 Residential Intellectual and Developmental Disability, Mental Health, and Substance Abuse Facilities. 6233 Continuing Care Retirement Communities and Assisted Living Facilities for the Elderly 6239 Other Residential Care Facilities. 6242 Community Food and Housing, and Emergency and Other Relief Services. 6243 Vocational Rehabilitation Services. 7111 Performing Arts Companies. 7112 Spectator Sports. 7121 Museums, Historical Sites, and Similar Institutions. 7131 Amusement Parks and Arcades. 7132 Gambling Industries. 7211 Traveler Accommodation. 7212 RV (Recreational Vehicle) Parks and Recreational Camps. 7223 Special Food Services. 8113 Commercial and Industrial Machinery and Equipment (except Automotive and Electronic) Repair and Maintenance. 8123 Drycleaning and Laundry Services. [88 FR 47347, July 21, 2023]
Appendix B to Subpart E of Part 1904—Designated Industries for § 1904.41(a)(2) Annual Electronic Submission of Information From OSHA Form 300 Log of Work-Related Injuries and Illnesses and OSHA Form 301 Injury and Illness Incident Report by Establishments With 100 or More Employees in Designated Industries NAICS Industry 1111 Oilseed and Grain Farming. 1112 Vegetable and Melon Farming. 1113 Fruit and Tree Nut Farming. 1114 Greenhouse, Nursery, and Floriculture Production. 1119 Other Crop Farming. 1121 Cattle Ranching and Farming. 1122 Hog and Pig Farming. 1123 Poultry and Egg Production. 1129 Other Animal Production. 1133 Logging. 1141 Fishing. 1142 Hunting and Trapping. 1151 Support Activities for Crop Production. 1152 Support Activities for Animal Production. 1153 Support Activities for Forestry. 2213 Water, Sewage and Other Systems. 2381 Foundation, Structure, and Building Exterior Contractors. 3111 Animal Food Manufacturing. 3113 Sugar and Confectionery Product Manufacturing. 3114 Fruit and Vegetable Preserving and Specialty Food Manufacturing. 3115 Dairy Product Manufacturing. 3116 Animal Slaughtering and Processing. 3117 Seafood Product Preparation and Packaging. 3118 Bakeries and Tortilla Manufacturing. 3119 Other Food Manufacturing. 3121 Beverage Manufacturing. 3161 Leather and Hide Tanning and Finishing. 3162 Footwear Manufacturing. 3211 Sawmills and Wood Preservation. 3212 Veneer, Plywood, and Engineered Wood Product Manufacturing. 3219 Other Wood Product Manufacturing. 3261 Plastics Product Manufacturing. 3262 Rubber Product Manufacturing. 3271 Clay Product and Refractory Manufacturing. 3272 Glass and Glass Product Manufacturing. 3273 Cement and Concrete Product Manufacturing. 3279 Other Nonmetallic Mineral Product Manufacturing. 3312 Steel Product Manufacturing from Purchased Steel. 3314 Nonferrous Metal (except Aluminum) Production and Processing. 3315 Foundries. 3321 Forging and Stamping. 3323 Architectural and Structural Metals Manufacturing. 3324 Boiler, Tank, and Shipping Container Manufacturing. 3325 Hardware Manufacturing. 3326 Spring and Wire Product Manufacturing. 3327 Machine Shops; Turned Product; and Screw, Nut, and Bolt Manufacturing. 3328 Coating, Engraving, Heat Treating, and Allied Activities. 3331 Agriculture, Construction, and Mining Machinery Manufacturing. 3335 Metalworking Machinery Manufacturing. 3361 Motor Vehicle Manufacturing. 3362 Motor Vehicle Body and Trailer Manufacturing. 3363 Motor Vehicle Parts Manufacturing. 3366 Ship and Boat Building. 3371 Household and Institutional Furniture and Kitchen Cabinet Manufacturing. 3372 Office Furniture (including Fixtures) Manufacturing. 3379 Other Furniture Related Product Manufacturing. 4231 Motor Vehicle and Motor Vehicle Parts and Supplies Merchant Wholesalers. 4233 Lumber and Other Construction Materials Merchant Wholesalers. 4235 Metal and Mineral (except Petroleum) Merchant Wholesalers. 4239 Miscellaneous Durable Goods Merchant Wholesalers. 4244 Grocery and Related Product Merchant Wholesalers. 4248 Beer, Wine, and Distilled Alcoholic Beverage Merchant Wholesalers. 4413 Automotive Parts, Accessories, and Tire Stores. 4422 Home Furnishings Stores. 4441 Building Material and Supplies Dealers. 4442 Lawn and Garden Equipment and Supplies Stores. 4451 Grocery Stores. 4522 Department Stores. 4523 General Merchandise Stores, including Warehouse Clubs and Supercenters. 4533 Used Merchandise Stores. 4543 Direct Selling Establishments. 4811 Scheduled Air Transportation. 4841 General Freight Trucking. 4842 Specialized Freight Trucking. 4851 Urban Transit Systems. 4852 Interurban and Rural Bus Transportation. 4853 Taxi and Limousine Service. 4854 School and Employee Bus Transportation. 4859 Other Transit and Ground Passenger Transportation. 4871 Scenic and Sightseeing Transportation, Land. 4881 Support Activities for Air Transportation. 4883 Support Activities for Water Transportation. 4889 Other Support Activities for Transportation. 4911 Postal Service. 4921 Couriers and Express Delivery Services. 4931 Warehousing and Storage. 5322 Consumer Goods Rental. 5621 Waste Collection. 5622 Waste Treatment and Disposal. 6219 Other Ambulatory Health Care Services. 6221 General Medical and Surgical Hospitals. 6222 Psychiatric and Substance Abuse Hospitals. 6223 Specialty (except Psychiatric and Substance Abuse) Hospitals. 6231 Nursing Care Facilities (Skilled Nursing Facilities). 6232 Residential Intellectual and Developmental Disability, Mental Health, and Substance Abuse Facilities. 6233 Continuing Care Retirement Communities and Assisted Living Facilities for the Elderly. 6239 Other Residential Care Facilities. 6243 Vocational Rehabilitation Services. 7111 Performing Arts Companies. 7112 Spectator Sports. 7131 Amusement Parks and Arcades. 7211 Traveler Accommodation. 7212 RV (Recreational Vehicle) Parks and Recreational Camps. 7223 Special Food Services. [88 FR 47348, July 21, 2023]
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]
[39 FR 23502, June 27, 1974]
Editorial Note: For Federal Register citations affecting § 1910.6, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.
Activity Fee = [Average (or Actual) Hours to Complete the Activity × Staff Costs per Hour] + Average (or Actual) Travel Costs
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.”
[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]
[73 FR 75583, Dec. 12, 2008]
[58 FR 35308, June 30, 1993]
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.
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.
[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.
[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]
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.
[81 FR 82981, Nov. 18, 2016, as amended at 84 FR 68795, Dec. 17, 2019]
[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:
[81 FR 82981, Nov. 18, 2016, as amended at 84 FR 68796, Dec. 17, 2019]
Figure D-13—Combination Handrail and Stair Rail
[81 FR 82981, Nov. 18, 2016, as amended at 84 FR 68796, Dec. 17, 2019]
This section lists the sections and paragraph headings contained in §§ 1910.34 through 1910.39.
[67 FR 67961, Nov. 7, 2002, as amended at 76 FR 33606, June 8, 2011]
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]
[67 FR 67961, Nov. 7, 2002, as amended at 76 FR 33606, June 8, 2011]
[67 FR 67961, Nov. 7, 2002]
[67 FR 67961, Nov. 7, 2002]
[67 FR 67961, Nov. 7, 2002]
Appendix to Subpart E of Part 1910—Exit Routes, Emergency Action Plans, and Fire Prevention Plans 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]
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.
[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]
[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]
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.
[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]
Table G-4—Grinding and Abrasive Cutting-Off Wheels 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: If wheel width = 4 1/2 inches, then 4.5 ÷ 4 × 610 = 686 (rounded to 690).
Table G-5—Buffing and Polishing Wheels 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
Table G-6—Horizontal Single-Spindle Disc Grinder 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
Table G-7—Horizontal Double-Spindle Disc Grinder 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
Table G-8—Vertical Spindle Disc Grinder 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.
Table G-9—Grinding and Polishing Belts 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
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.
Standard Buffing and Polishing Hood 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.
Table G-10—Minimum Maintained Velocities Into Spray Booths 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. (1) LEL of toluene from Table G-11, column 2, is 1.4 percent. (2) Cubic feet of vapor per gallon from Table G-11, column 1, is 30.4 cubic feet per gallon. (3) Dilution volume required= 4 (100−1.4) 30.4 ÷ 1.4 = 8,564 cubic feet. (4) To convert to cubic feet per minute of required ventilation, multiply the dilution volume required per gallon of solvent by the number of gallons of solvent evaporated per minute.
Table G-11—Lower Explosive Limit of Some Commonly Used Solvents 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.
[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]
Figure G-9
Table G-16—Permissible Noise Exposures 1 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.
[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]
This guide applies whether the radiation is continuous or intermittent.
Figure G-11—Radio-Frequency Radiation Hazard Warning Symbol
[39 FR 23502, June 27, 1974, as amended at 61 FR 9236, Mar. 7, 1996; 78 FR 35566, June 13, 2013]
[39 FR 23502, June 27, 1974, as amended at 61 FR 9236, Mar. 7, 1996]
[74 FR 40447, Aug. 11, 2009, as amended at 76 FR 75786, Dec. 5, 2011]
Table H-1 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.
Table H-2 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).
Table H-3—Maximum Total Quantity of Liquefied Hydrogen Storage Permitted 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.
Table H-4—Minimum Distance (Feet) From Liquefied Hydrogen Systems to Exposure 1 2 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.
[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]
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.
[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]
This paragraph may be used for operating pressures not exceeding 1 p.s.i.g.
Table H-10—Wetted Area Versus Cubic Feet Free Air Per Hour [14.7 psia and 60 °F.] 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
CFH = 1,107A 0.82
V = 1337 ÷ L√M
Table H-11—Vent Line Diameters 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.
Table H-12—Maximum Allowable Size of Containers and Portable Tanks for Flammable Liquids 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).
Table H-13—Storage in Inside Rooms 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.
Table H-18—Electrical Equipment Hazardous Areas—Bulk Plants 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.
[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]
( 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
[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]
Table H-21—American Table of Distances for Storage of Explosives 1-5 [As revised and approved by the Institute of Makers of Explosives, June 5, 1964] 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).
Table H-22—Table of Recommended Separation Distances of Ammonium Nitrate and Blasting Agents From Explosives or Blasting Agents 1-6 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.
[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]
Table H-23 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.
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.
Table H-24—Wall Thickness of Copper Tubing 1 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.
Table H-25—Wall Thickness of Aluminum Alloy Tubing 1 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.
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
Air Conversion Factors 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:
Table H-26 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.
Water capacity per container (gallons) Minimum distances (feet) Less than 501 10 501 to 2,000 25 Over 2,000 50
Table H-27—Maximum Permitted Filling Density 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
Table H-28 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.
Figure H-1
[(Water capacity (gals.) of container* × filling density**) ÷ (Specific gravity of LP-Gas* × volume correction factor × 100)] = Maximum volume of LP-Gas
Table H-29—Volume Correction Factors 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) (4200 ÷ 52.6) = 79.8 gallons propane, the maximum amount permitted to be placed in a 100-gallon total water capacity aboveground container equipped with a fixed dip tube. [(Maximum volume of LP-Gas (from formula in subdivision ( b ) of this subdivision) × 100) ÷ Total water content of container in gallons] = Maximum percent of LP-Gas
Aboveground, pounds per gallon Underground, pounds per gallon Propane 4.37 4.31 N Butane 4.97 4.92
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.
Table H-30 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
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.
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.
Table H-32 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.
Table H-33 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.
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.
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.
[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]
In lieu of this requirement the same information may be contained on a nameplate permanently attached to the hose.
Table H-36 [Minimum required rate of discharge in cubic feet per minute of air at 120 percent of the maximum permitted start to discharge pressure of safety relief valves] 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
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.
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.
[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.
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).
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).
[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]
Appendix B to § 1910.119—Block Flow Diagram and Simplified Process Flow Diagram (Nonmandatory)
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:
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.
Table H-120.1—Minimum Illumination Intensities in Foot-Candles 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.
Table H-120.2—Toilet Facilities 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.
[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.
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]
[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]
[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.
[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).
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.
Table 1—Assigned Protection Factors 5 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).
Table I—Assigned Protection Factors [Reserved]
Table 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.
[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]
[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]
Table I-1—AC Proof-Test Requirements 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
Table I-2—DC Proof-Test Requirements 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.
Table I-3—Glove Tests—Water Level 1 2 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.).
Table I-4—Rubber Insulating Equipment, Voltage Requirements 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.
Table I-5—Rubber Insulating Equipment, Test Intervals 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]
[59 FR 16362, Apr. 6, 1994; 59 FR 33911, July 1, 1994]
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)).
[81 FR 82999, Nov. 18, 2016, as amended at 84 FR 68797, Dec. 17, 2019]
Appendix A to Subpart I of Part 1910—References for Further Information (Non-mandatory) 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]
Appendix B to Subpart I of Part 1910—Nonmandatory Compliance Guidelines for Hazard Assessment and Personal Protective Equipment Selection 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: (a) Impact (b) Penetration (c) Compression (roll-over) (d) Chemical (e) Heat (f) Harmful dust (g) Light (optical) radiation 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. Eye and Face Protection Selection Chart 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: (A) As long as the performance characteristics are acceptable, in certain circumstances, it may be more cost effective to regularly change cheaper gloves than to reuse more expensive types; and, (B) The work activities of the employee should be studied to determine the degree of dexterity required, the duration, frequency, and degree of exposure of the hazard, and the physical stresses that will be applied. With respect to selection of gloves for protection against chemical hazards: (A) The toxic properties of the chemical(s) must be determined; in particular, the ability of the chemical to cause local effects on the skin and /or to pass through the skin and cause systemic effects; (B) Generally, any “chemical resistant” glove can be used for dry powders; (C) For mixtures and formulated products (unless specific test data are available), a glove should be selected on the basis of the chemical component with the shortest breakthrough time, since it is possible for solvents to carry active ingredients through polymeric materials; and, (D) Employees must be able to remove the gloves in such a manner as to prevent skin contamination. 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]
Appendix C to Subpart I of Part 1910—Personal Fall Protection Systems Non-Mandatory Guidelines 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. (a) Planning considerations. 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. (b) Selection and use considerations. (1) The kind of personal fall protection system selected should be appropriate for the employee's specific work situation. Free fall distances should always be kept to a minimum. Many systems are designed for particular work applications, such as climbing ladders and poles; maintaining and servicing equipment; and window cleaning. Consideration should be given to the environment in which the work will be performed. For example, the presence of acids, dirt, moisture, oil, grease, or other substances, and their potential effects on the system selected, should be evaluated. The employer should fully evaluate the work conditions and environment (including seasonal weather changes) before selecting the appropriate personal fall protection system. Hot or cold environments may also affect fall protection systems. Wire rope should not be used where electrical hazards are anticipated. As required by § 1910.140(c)(21), the employer must provide a means for promptly rescuing an employee should a fall occur. (2) Where lanyards, connectors, and lifelines are subject to damage by work operations, such as welding, chemical cleaning, and sandblasting, the component should be protected, or other securing systems should be used. A program for cleaning and maintaining the system may be necessary. (c) Testing considerations. 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. (d) Component compatibility considerations. 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. (e) Employee training considerations. 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. (f) Instruction considerations. Employers should obtain comprehensive instructions from the supplier or a qualified person as to the system's proper use and application, including, where applicable: (1) The force measured during the sample force test; (2) The maximum elongation measured for lanyards during the force test; (3) The deceleration distance measured for deceleration devices during the force test; (4) Caution statements on critical use limitations; (5) Limits of the system; (6) Proper hook-up, anchoring and tie-off techniques, including the proper D-ring or other attachment point to use on the body harness; (7) Proper climbing techniques; (8) Methods of inspection, use, cleaning, and storage; and (9) Specific lifelines that may be used. (g) Inspection considerations. 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. (h) Rescue considerations. 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. (i) Tie-off considerations. 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: (1) Tie-off using a knot in the lanyard or lifeline (at any location). The strength of the line can be reduced by 50 percent or more if a knot is used. Therefore, a stronger lanyard or lifeline should be used to compensate for the knot, or the lanyard length should be reduced (or the tie-off location raised) to minimize free fall distance, or the lanyard or lifeline should be replaced by one which has an appropriately incorporated connector to eliminate the need for a knot. (2) Tie-off around rough or sharp ( e.g., “H” or “I” beams) surfaces. Sharp or rough surfaces can damage rope lines and this reduces strength of the system drastically. Such tie-offs should be avoided whenever possible. An alternate means should be used such as a snaphook/D-ring connection, a tie-off apparatus (steel cable tie-off), an effective padding of the surfaces, or an abrasion-resistant strap around the supporting member. If these alternative means of tie-off are not available, the employer should try to minimize the potential free fall distance. (3) Knots. 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. (j) Horizontal lifelines. 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. (k) Eye-bolts. 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). (l) Vertical lifeline considerations. 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. (m) Snaphook and carabiner considerations. 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: (1) Direct connection to webbing, rope, or a horizontal lifeline; (2) Two (or more) snaphooks or carabiners connected to one D-ring; (3) Two snaphooks or carabiners connected to each other; (4) Snaphooks or carabiners connected directly to webbing, rope, or wire rope; and (5) Improper dimensions of the D-ring, rebar, or other connection point in relation to the snaphook or carabiner dimensions which would allow the gate to be depressed by a turning motion. (n) Free fall considerations. 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. (o) Elongation and deceleration distance considerations. 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. (p) Obstruction considerations. 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]
Appendix D to Subpart I of Part 1910—Test Methods and Procedures for Personal Fall Protection Systems Non-Mandatory Guidelines 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). (a) General. The following sets forth test procedures for personal fall arrest systems as defined in paragraph (d) of § 1910.140. (b) General test conditions. (1) Lifelines, lanyards and deceleration devices should be attached to an anchorage and connected to the body harness in the same manner as they would be when used to protect employees. (2) The fixed anchorage should be rigid, and should not have a deflection greater than 0.04 inches (1 mm) when a force of 2,250 pounds (10 kN) is applied. (3) The frequency response of the load measuring instrumentation should be 120 Hz. (4) The test weight used in the strength and force tests should be a rigid, metal cylindrical or torso-shaped object with a girth of 38 inches plus or minus 4 inches (96 cm plus or minus 10 cm). (5) The lanyard or lifeline used to create the free fall distance should be supplied with the system, or in its absence, the least elastic lanyard or lifeline available should be used with the system. (6) The test weight for each test should be hoisted to the required level and should be quickly released without having any appreciable motion imparted to it. (7) The system's performance should be evaluated, taking into account the range of environmental conditions for which it is designed to be used. (8) Following the test, the system need not be capable of further operation. (c) Strength test. (1) During the testing of all systems, a test weight of 300 pounds plus or minus 3 pounds (136.4 kg plus or minus 1.4 kg) should be used. (See paragraph (b)(4) of this appendix.) (2) The test consists of dropping the test weight once. A new unused system should be used for each test. (3) For lanyard systems, the lanyard length should be 6 feet plus or minus 2 inches (1.83 m plus or minus 5 cm) as measured from the fixed anchorage to the attachment on the body harness. (4) For rope-grab-type deceleration systems, the length of the lifeline above the centerline of the grabbing mechanism to the lifeline's anchorage point should not exceed 2 feet (0.61 m). (5) For lanyard systems, for systems with deceleration devices which do not automatically limit free fall distance to 2 feet (0.61 m) or less, and for systems with deceleration devices which have a connection distance in excess of 1 foot (0.3 m) (measured between the centerline of the lifeline and the attachment point to the body harness), the test weight should be rigged to free fall a distance of 7.5 feet (2.3 m) from a point that is 1.5 feet (46 cm) above the anchorage point, to its hanging location (6 feet (1.83 m) below the anchorage). The test weight should fall without interference, obstruction, or hitting the floor or ground during the test. In some cases a non-elastic wire lanyard of sufficient length may need to be added to the system (for test purposes) to create the necessary free fall distance. (6) For deceleration device systems with integral lifelines or lanyards that automatically limit free fall distance to 2 feet (0.61 m) or less, the test weight should be rigged to free fall a distance of 4 feet (1.22 m). (7) Any weight that detaches from the harness should constitute failure for the strength test. (d) Force test. (1) General. 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. (2) For lanyard systems. (i) A test weight of 220 pounds plus or minus three pounds (100 kg plus or minus 1.6 kg) should be used. (See paragraph (b)(4) of this appendix.) (ii) Lanyard length should be 6 feet plus or minus 2 inches (1.83 m plus or minus 5 cm) as measured from the fixed anchorage to the attachment on the body harness. (iii) The test weight should fall free from the anchorage level to its hanging location (a total of 6 feet (1.83 m) free fall distance) without interference, obstruction, or hitting the floor or ground during the test. (3) For all other systems. (i) A test weight of 220 pounds plus or minus 2 pounds (100 kg plus or minus 1.0 kg) should be used. (See paragraph (b)(4) of this appendix.) (ii) The free fall distance to be used in the test should be the maximum fall distance physically permitted by the system during normal use conditions, up to a maximum free fall distance for the test weight of 6 feet (1.83 m), except as follows: (A) For deceleration systems having a connection link or lanyard, the test weight should free fall a distance equal to the connection distance (measured between the centerline of the lifeline and the attachment point to the body harness). (B) For deceleration device systems with integral lifelines or lanyards that automatically limit free fall distance to 2 feet (0.61 m) or less, the test weight should free fall a distance equal to that permitted by the system in normal use. (For example, to test a system with a self-retracting lifeline or lanyard, the test weight should be supported and the system allowed to retract the lifeline or lanyard as it would in normal use. The test weight would then be released and the force and deceleration distance measured). (4) Failure. A system fails the force test when the recorded maximum arresting force exceeds 2,520 pounds (11.2 kN) when using a body harness. (5) Distances. The maximum elongation and deceleration distance should be recorded during the force test. (e) Deceleration device tests. (1) General. 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. (2) Rope-grab-type deceleration devices. (i) Devices should be moved on a lifeline 1,000 times over the same length of line a distance of not less than 1 foot (30.5 cm), and the mechanism should lock each time. (ii) Unless the device is permanently marked to indicate the type of lifelines that must be used, several types (different diameters and different materials), of lifelines should be used to test the device. (3) Other self-activating-type deceleration devices. 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). (a) General. 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. (b) Test conditions. (1) The fixed anchorage should be rigid and should not have a deflection greater than 0.04 inches (1 mm) when a force of 2,250 pounds (10 kN) is applied. (2) For window cleaners' belts, the complete belt should withstand a drop test consisting of a 250 pound (113 kg) weight falling free for a distance of 6 feet (1.83 m). The weight should be a rigid object with a girth of 38 inches plus or minus 4 inches (96 cm plus or minus 10 cm). The weight should be placed in the waistband with the belt buckle drawn firmly against the weight, as when the belt is worn by a window cleaner. One belt terminal should be attached to a rigid anchor and the other terminal should hang free. The terminals should be adjusted to their maximum span. The weight fastened in the freely suspended belt should then be lifted exactly 6 feet (1.83 m) above its “at rest” position and released so as to permit a free fall of 6 feet (1.83 m) vertically below the point of attachment of the terminal anchor. The belt system should be equipped with devices and instrumentation capable of measuring the duration and magnitude of the arrest forces. Failure of the test should consist of any breakage or slippage sufficient to permit the weight to fall free of the system. In addition, the initial and subsequent arresting forces should be measured and should not exceed 2,000 pounds (8.5 kN) for more than 2 milliseconds for the initial impact, or exceed 1,000 pounds (4.5 kN) for the remainder of the arrest time. (3) All other positioning systems (except for restraint line systems) should withstand a drop test consisting of a 250 pound (113 kg) weight free falling a distance of 4 feet (1.2 m). The weight must be a rigid object with a girth of 38 inches plus or minus 4 inches (96 cm plus or minus 10 cm). The body belt or harness should be affixed to the test weight as it would be to an employee. The system should be connected to the rigid anchor in the manner that the system would be connected in normal use. The weight should be lifted exactly 4 feet (1.2 m) above its “at rest” position and released so as to permit a vertical free fall of 4 feet (1.2 m). Failure of the system should be indicated by any breakage or slippage sufficient to permit the weight to fall free to the ground. [81 FR 83002, Nov. 18, 2016]
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.
Table J-1 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.
[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]
[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]
[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]
Figure J-7—Slow-Moving Vehicle Emblem
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.
Biological Hazard Symbol Configuration
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.
[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]
Appendix A to § 1910.146—Permit-Required Confined Space Decision Flow Chart
Appendix D to § 1910.146—Sample Permits
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.
[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]
[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]
[45 FR 60704, Sept. 12, 1980, as amended at 53 FR 12122, Apr. 12, 1988]
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]
Table L-1 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]
[45 FR 60710, Sept. 12, 1980, as amended at 61 FR 9239, Mar. 7, 1996]
[45 FR 60710, Sept. 12, 1980; 46 FR 24557, May 1, 1981]
[45 FR 60711, Sept. 12, 1980]
[45 FR 60712, Sept. 12, 1980]
[45 FR 60712, Sept. 12, 1980; 46 FR 24557, May 1, 1981]
[45 FR 60712, Sept. 12, 1980]
[45 FR 60713, Sept. 12, 1980]
[45 FR 60713, Sept. 12, 1980]
Appendixes to Subpart L of Part 1910—Note Note: The following appendices to subpart L, except appendix E, serve as nonmandatory guidelines to assist employers in complying with the appropriate requirements of subpart L.
Appendix A to Subpart L of Part 1910—Fire Protection § 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. (A) General. 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. (B) Foot and leg protection. 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. (C) Body protection. 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. (D) Hand protection. 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. (E) Head, eye, and face protection. Head protective devices which meet the requirements contained in NFPA No. 1972 are acceptable as meeting the requirements of this standard for head protection. 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: (a) Normal breathing with head motionless for one minute; (b) Deep breathing with head motionless for 30 seconds; (c) Turning head slowly from side to side while breathing normally, pausing for at least two breaths before changing direction. Continue for at least one minute; (d) Moving head slowly up and down while breathing normally, pausing for at least two breaths before changing direction. Continue for at least two minutes; (e) Reading from a prepared text, slowly and clearly, and loudly enough to be heard and understood. Continue for one minute; and (f) Normal breathing with head motionless for at least one minute. 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]
Appendix B to Subpart L of Part 1910—National Consensus Standards 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]
Appendix C to Subpart L of Part 1910—Fire Protection References For Further Information 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]
Appendix D to Subpart L of Part 1910—Availability of Publications Incorporated by Reference in Section 1910.156 Fire Brigades 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]
Appendix E to Subpart L of Part 1910—Test Methods for Protective Clothing 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. (1) Puncture resistance test method for foot protection. 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. (2) Test method for determining the strength of cloth by tearing: Trapezoid Method. 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. (i) Six-ounce (.17 kg) weight tension clamps shall be used so designed that the six ounces (.17 kg) of weight are distributed evenly across the complete width of the sample. (ii) The machine shall consist of three main parts: Straining mechanism, clamps for holding specimen, and load and elongation recording mechanisms. (iii) A machine wherein the specimen is held between two clamps and strained by a uniform movement of the pulling clamp shall be used. (iv) The machine shall be adjusted so that the pulling clamp shall have a uniform speed of 12 ±10.5 inches per minute (0.5 ±.02 cm/sec). (v) The machine shall have two clamps with two jaws on each clamp. The design of the two clamps shall be such that one gripping surface or jaw may be an integral part of the rigid frame of the clamp or be fastened to allow a slight vertical movement, while the other gripping surface or jaw shall be completely moveable. The dimension of the immovable jaw of each clamp parallel to the application of the load shall measure one-inch, and the dimension of the jaw perpendicular to this direction shall measure three inches or more. The face of the movable jaw of each clamp shall measure one-inch by three inches. 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. (vi) Calibrated dial; scale or chart shall be used to indicate applied load and elongation. The machine shall be adjusted or set, so that the maximum load required to break the specimen will remain indicated on the calibrated dial or scale after the test specimen has ruptured. (vii) The machine shall be of such capacity that the maximum load required to break the specimen shall be not greater than 85 percent or less than 15 percent of the rated capacity. (viii) The error of the machine shall not exceed 2 percent up to and including a 50-pound load (22.6 kg) and 1 percent over a 50-pound load (22.6 kg) at any reading within its loading range. (ix) All machine attachments for determining maximum loads shall be disengaged during this test. C. Procedure. (i) The specimen shall be clamped in the machine along the nonparallel sides of the trapezoid so that these sides lie along the lower edge of the upper clamp and the upper edge of the lower clamp with the cut halfway between the clamps. The short trapezoid base shall be held taut and the long trapezoid base shall lie in the folds. (ii) The machine shall be started and the force necessary to tear the cloth shall be observed by means of an autographic recording device. The speed of the pulling clamp shall be 12 inches ±0.5 inch per minute (0.5 ±.02 cm/sec). (iii) If a specimen slips between the jaws, breaks in or at the edges of the jaws, or if for any reason attributable to faulty technique, an individual measurement falls markedly below the average test results for the sample unit, such result shall be discarded and another specimen shall be tested. (iv) The tearing strength of the specimen shall be the average of the five highest peak loads of resistance registered for 3 inches (7.6 cm) of separation of the tear. D. Report. (i) Five specimens in each of the warp and filling directions shall be tested from each sample unit. (ii) The tearing strength of the sample unit shall be the average of the results obtained from the specimens tested in each of the warp and filling directions and shall be reported separately to the nearest 0.1-pound (.05 kg). E. Source. These test requirements are contained in “Federal Test Method Standard 191, Method 5136” and are reproduced for your convenience. (3) Test method for determining flame resistance of cloth; vertical. 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. (i) Cabinet. 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. (ii) Burner. 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. (a) The burner may be constructed by combining a 3/8 -inch (1 cm) inside diameter barrel 3 ± 1/4 inches (7.6 ±.6 cm) long from a fixed orifice burner with a base from a variable orifice burner. (b) The pilot light tube shall have a diameter of approximately 1/16 -inch (.2 cm) and shall be spaced 1/8 -inch (.3 cm) away from the burner edge with a pilot flame 1/8 -inch (.3 cm) long. (c) The necessary gas connections and the applicable plumbing shall be as specified in Figure L-4 except that a solenoid valve may be used in lieu of the stopcock valve to which the burner is attached. The stopcock valve or solenoid valve, whichever is used, shall be capable of being fully opened or fully closed in 0.1-second. (d) On the side of the barrel of the burner, opposite the pilot light there shall be a metal rod of approximately 1/8 -inch (.3 cm) diameter spaced 1/2 -inch (1.3 cm) from the barrel and extending above the burner. The rod shall have two 5/16 -inch (.8 cm) prongs marking the distances of 3/4 -inch (1.9 cm) and 1 1/2 inches (3.8 cm) above the top of the burner. (e) The burner shall be fixed in a position so that the center of the barrel of the burner is directly below the center of the specimen. (iii) There shall be a control valve system with a delivery rate designed to furnish gas to the burner under a pressure of 2 1/2 ± 1/4 (psi) (17.5 ±1.8 kPa) per square inch at the burner inlet (see (g)(3)(vi)(A)). The manufacturer's recommended delivery rate for the valve system shall be included in the required pressure. (iv) A synthetic gas mixture shall be of the following composition within the following limits (analyzed at standard conditions): 55 ±3 percent hydrogen, 24 ±1 percent methane, 3 ±1 percent ethane, and 18 ±1 percent carbon monoxide which will give a specific gravity of 0.365 ±0.018 (air = 1) and a B.T.U. content of 540 ±20 per cubic foot (20.1 ±3.7 kJ/L)(dry basis) at 69.8 °F (21 °C). (v) There shall be metal hooks and weights to produce a series of total loads to determine length of char. The metal hooks shall consist of No. 19 gage steel wire or equivalent and shall be made from 3-inch (7.6 cm) lengths of wire and bent 1/2 -inch (1.3 cm) from one end to a 45 degree hook. One end of the hook shall be fastened around the neck of the weight to be used. (vi) There shall be a stop watch or other device to measure the burning time to 0.2-second. (vii) There shall be a scale, graduated in 0.1 inch (.3 cm) to measure the length of char. D. Procedure. (i) The material undergoing test shall be evaluated for the characteristics of after-flame time and char length on each specimen. (ii) All specimens to be tested shall be at moisture equilibrium under standard atmospheric conditions in accordance with paragraph (3)C of this appendix. Each specimen to be tested shall be exposed to the test flame within 20 seconds after removal from the standard atmosphere. In case of dispute, all testing will be conducted under Standard Atmospheric Conditions in accordance with paragraph (3)C of this appendix. (iii) The specimen in its holder shall be suspended vertically in the cabinet in such a manner that the entire length of the specimen is exposed and the lower end is 3/4 -inch (1.9 cm) above the top of the gas burner. The apparatus shall be set up in a draft free area. (iv) Prior to inserting the specimen, the pilot flame shall be adjusted to approximately 1/8 -inch (.3 cm) in height measured from its lowest point to the tip. 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. (v) The after-flame shall be the time the specimen continues to flame after the burner flame is shut off. (vi) After each specimen is removed, the test cabinet shall be cleared of fumes and smoke prior to testing the next specimen. (vii) After both flaming and glowing have ceased, the char length shall be measured. The char length shall be the distance from the end of the specimen, which was exposed to the flame, to the end of a tear (made lengthwise) of the specimen through the center of the charred area as follows: The specimen shall be folded lengthwise and creased by hand along a line through the highest peak of the charred area. The hook shall be inserted in the specimen (or a hole, 1/4 -inch (.6 cm) diameter or less, punched out for the hook) at one side of the charred area 1/4 -inch (.6 cm) from the adjacent outside edge and 1/4 -inch (.6 cm) in from the lower end. A weight of sufficient size such that the weight and hook together shall equal the total tearing load required in Table L-2 of this section shall be attached to the hook. (viii) A tearing force shall be applied gently to the specimen by grasping the corner of the cloth at the opposite edge of the char from the load and raising the specimen and weight clear of the supporting surface. The end of the tear shall be marked off on the edge and the char length measurement made along the undamaged edge. Loads for determining char length applicable to the weight of the test cloth shall be as shown in Table L-2. Table L-2 1 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. (ix) The after-flame time of the specimen shall be recorded to the nearest 0.2-second and the char length to the nearest 0.1-inch (.3 cm). E. Report. (i) The after-flame time and char length of the sample unit shall be the average of the results obtained from the individual specimens tested. All values obtained from the individual specimens shall be recorded. (ii) The after-flame time shall be reported to the nearest 0.2-second and the char length to the nearest 0.1-inch (.3 cm). 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]
[39 FR 23502, June 27, 1974, as amended at 49 FR 5322, Feb. 10, 1984; 61 FR 9239, Mar. 7, 1996]
[39 FR 23052, June 27, 1974, as amended at 43 FR 49749, Oct. 24, 1978]
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).
[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]
Table N-1—Summary Table on Use of Industrial Trucks in Various Locations 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.
Table N-1—Summary Table on Use of Industrial Trucks in Various Locations—Continued 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.
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.
[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]
[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]
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.
[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]
[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]
[40 FR 13440, Mar. 26, 1975, as amended at 63 FR 33467, June 18, 1998]
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 load is the load applied in performance of a proof test.
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.)
Table N-184-1—Minimum Allowable Chain Size At Any Point of Link 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
[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]
Figure No. 0-1—Type 1 Straight Wheels
Type 1—Straight Wheel
Peripheral grinding wheel having a diameter, thickness and hole.
Figure No. 0-2—Type 2 Cylinder Wheels
Type 2—Cylinder Wheel
Figure No. 0-3—Type 6 Straight Cup Wheels
Type 6—Straight-cup Wheel
Figure No. 0-4—Type 11 Flaring Cup Wheels
Type 11—Flaring-cup Wheel
Figure No. 0-5
Typical examples of modified types 6 and 11 wheels (terrazzo) showing tapered K dimensions.
Examples: (a) 24-inch diameter wheel, 1,000 revolutions per minute. Surface Feet per minute .262 × 24 × 1,000 = 6,288 s.f.p.m. (b) 12-inch diameter wheel, 1,000 revolutions per minute. Surface Feet per minute .262 × 12 × 1,000 = 3,144 s.f.p.m.
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]
[39 FR 23502, June 27, 1974, as amended at 43 FR 49750, Oct. 24, 1978; 49 FR 5323, Feb. 10, 1984]
Figure No. O-6 Figure No. O-7
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.)
Figure No. O-8 Figure No. O-9
Figure No. O-10 Figure No. O-11
Figure No. O-12 Figure No. O-13
Figure No. O-14 Figure No. O-15
Figure No. O-16 Figure No. O-17
Figure No. O-18 Figure No. O-19
correct
Showing adjustable tongue giving required angular protection for all sizes of wheel used.
Figure No. O-20 Figure No. O-21
correct
Showing movable guard with opening small enough to give required protection for smallest size wheel used.
Figure No. O-22 Figure No. O-23
incorrect
Showing movable guard with size of opening correct for full size wheel but too large for smaller wheels.
Figure No. O-24
The Type 27 A Wheel is mounted between flat non-relieved flanges of equal bearing surfaces.
Figure No. O-24-A
Types 27 and 28 wheels, because of their shape, require specially designed adaptors.
Figure No. O-25 Figure No. O-26
Table O-1—Minimum Basic Thickness for Peripheral and Side Members for Safety Guards Used With Cutting-Off Wheels 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
Table O-3—Guide for Construction of Band Type Guards [Maximum Wheel Speed 7,000 SFPM] 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
Table O-5—Minimum Dimensions for Straight Adaptor Flange—for Organic Bonded Wheels Over 1 1 ⁄ 4 Inches Thick 1 [In inches] 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.
Table O-6—Minimum Dimensions for Straight Relieved Flanges 1 [In inches] 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.
Table O-7—Minimum Dimensions for Straight Flanges—for Mechanical Grinders 12,500 S.F.P.M. to 16,5 S.F.P.M. 1 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.
Table O-8—Minimum Dimensions for Straight Flanges Used as Wheel Sleeves for Precision Grinding Only [In inches] 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.
Table O-9—Minimum Basic Thicknesses of Peripheral and Side Members for Safety Guards [In inches] 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.
Table O-2—Exposure Versus Wheel Thickness [In inches] 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
Table O-4—Minimum Dimensions for Straight Unrelieved Flanges for Wheels with Threaded Inserts or Projecting Studs 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]
[39 FR 23502, June 27, 1974, as amended at 49 FR 5323, Feb. 10, 1984; 61 FR 9240, Mar. 7, 1996]
D s = 63 inches/second × T s
D s = 63 inches/second × T s ;
D m = 63 inches/second × T m ;
Ds = Hs × (Ts + Tp + Tr + 2Tm) + Dp
[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]
Table O-11—Strength and Dimensions for Wood Ram Props 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.
[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]
[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:
Type 11 Flaring Cup Wheels
Figure P-1
[39 FR 23502, June 27, 1974, as amended at 43 FR 49750, Oct. 24, 1978]
Figure No. P-4
Figure No. P-5
Figure No. P-6
[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]
[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]
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.
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.
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.
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.
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.
[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]
[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]
[55 FR 13696, Apr. 11, 1990, as amended at 61 FR 9241, Mar. 7, 1996; 70 FR 53929, Sept. 13, 2005]
A zero speed switch should be installed to prevent the guard from being raised while the roll is turning.
[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]
Table R-1—Guard Openings [Openings in the guard or between the guard and working surface shall not be greater than the following] 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.
[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]
[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]
[39 FR 23502, June 27, 1974, as amended at 43 FR 49767, Oct. 24, 1978; 43 FR 51760, Nov. 7, 1978]
[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]
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.
[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]
Table R-2—Approach Distances to Exposed Energized Overhead Power Lines and Parts 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.
Gloves, blankets, and other insulating equipment Natural rubber Synthetic rubber Months New 12 18 Re-issued 9 15
Table R-3—Minimum Working Distances From Energized Conductors for Line-Clearance Tree Trimmers and Line-Clearance Tree-Trimmer Trainees 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.
[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]
Table R-2—Flammability Test 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
Table R-3—AC Live-Line Work Minimum Approach Distance [The minimum approach distance (MAD; in meters) shall conform to the following equations.] 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.
Table R-4—Electrical Component of the Minimum Approach Distance at 5.1 to 72.5 kV [D; In meters] 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
Table R-5—Altitude Correction Factor 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
Table R-6—Alternative Minimum Approach Distances for Voltages of 72.5 kV and Less 1 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.
Table R-7—Alternative Minimum Approach Distances for Voltages of More Than 72.5 kV 1 2 3 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.
Table R-8—DC Live-Line Minimum Approach Distance with Overvoltage Factor 1 [In meters] 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.
Table R-9—Assumed Maximum Per-Unit Transient Overvoltage 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
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 —(1) Communication 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.
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.
Table 1—Electrical Safety Requirements in § 1910.269 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.
Table 6—Minimum Approach Distances Until December 31, 2014 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.
Table 7—Minimum Approach Distances Until March 31, 2015—72.6 to 121.0 kV With Overvoltage Factor 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.
Table 8—Minimum Approach Distances Until March 31, 2015—121.1 to 145.0 kV With Overvoltage Factor 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.
Table 9—Minimum Approach Distances Until March 31, 2015—145.1 to 169.0 kV With Overvoltage Factor 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.
Table 10—Minimum Approach Distances Until March 31, 2015—169.1 to 242.0 kV With Overvoltage Factor 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.
Table 11—Minimum Approach Distances Until March 31, 2015—242.1 to 362.0 kV With Overvoltage Factor 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.
Table 12—Minimum Approach Distances Until March 31, 2015—362.1 to 552.0 kV With Overvoltage Factor 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.
Table 13—Minimum Approach Distances Until March 31, 2015—552.1 to 800.0 kV With Overvoltage Factor 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.
Table 14—AC Minimum Approach Distances—72.6 to 121.0 kV 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
Table 15—AC Minimum Approach Distances—121.1 to 145.0 kV 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
Table 16—AC Minimum Approach Distances—145.1 to 169.0 kV 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
Table 17—AC Minimum Approach Distances—169.1 to 242.0 kV 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
Table 18—AC Minimum Approach Distances—242.1 to 362.0 kV 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
Table 19—AC Minimum Approach Distances—362.1 to 420.0 kV 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
Table 20—AC Minimum Approach Distances—420.1 to 550.0 kV 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
Table 21—AC Minimum Approach Distances—550.1 to 800.0 kV 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.
[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]
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.
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:
[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.
§ 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
Table S-1—Minimum Depth of Clear Working Space at Electric Equipment, 600 V or Less 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.
“DANGER—HIGH VOLTAGE—KEEP OUT.”
Table S-2—Minimum Depth of Clear Working Space at Electric Equipment, Over 600 V 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.
Table S-3—Elevation of Unguarded Live Parts Above Working Space 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]
Table S-4—Maximum Cord- and Plug-Connected Load to Receptacle Circuit rating (amperes) Receptacle rating (amperes) Maximum load (amperes) 15 or 20 15 12 20 20 16 30 30 24
Table S-5—Receptacle Ratings for Various Size Circuits Circuit rating (amperes) Receptacle rating (amperes) 15 Not over 15. 20 15 or 20. 30 30. 40 40 or 50. 50 50.
Table S-6—Clearances From Ground 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.
( 8 Portable hand lamps.
[46 FR 4056, Jan. 16, 1981, as amended at 73 FR 64205, Oct. 29, 2008]
[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]
Table S-4—Typical Occupational Categories of Employees Facing a Higher Than Normal Risk of Electrical Accident 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]
Table S-5—Approach Distances for Qualified Employees—Alternating Current 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).
[55 FR 32016, Aug. 6, 1990; 55 FR 46053, Nov. 1, 1990, as amended at 59 FR 4476, Jan. 31, 1994]
[55 FR 32019, Aug. 6, 1990]
[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 —(1) Bare. A conductor having no covering or electrical insulation whatsoever.
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 —(1) Damp 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.
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:
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 —(1) General-use 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.
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]
Appendix A to Subpart S of Part 1910— References for Further Information 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]
[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]
[42 FR 37668, July 22, 1977, as amended at 49 FR 18295, Apr. 30, 1984]
[42 FR 37668, July 22, 1977, as amended at 47 FR 14706, Apr. 6, 1982; 54 FR 24334, June 7, 1989]
[42 FR 37668, July 22, 1977, as amended at 49 FR 18295, Apr. 30, 1984]
[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]
Appendix A to Subpart T of Part 1910—Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions 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.
Appendix B to Subpart T of Part 1910—Guidelines for Scientific Diving 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]
Appendix C to Subpart T of Part 1910—Alternative Conditions Under § 1910.401( a )(3) for Recreational Diving Instructors and Diving Guides (Mandatory) 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 (a) The employer must ensure that each employee operates the rebreather ( i.e., semi-closed-circuit and closed-circuit self-contained underwater breathing apparatuses (hereafter, “SCUBAs”)) according to the rebreather manufacturer's instructions. (b) The employer must ensure that each rebreather has a counterlung that supplies a sufficient volume of breathing gas to their divers to sustain the divers' respiration rates, and contains a baffle system and/or other moisture separating system that keeps moisture from entering the scrubber. (c) The employer must place a moisture trap in the breathing loop of the rebreather, and ensure that: (i) The rebreather manufacturer approves both the moisture trap and its location in the breathing loop; and (ii) Each employee uses the moisture trap according to the rebreather manufacturer's instructions. (d) The employer must ensure that each rebreather has a continuously functioning moisture sensor, and that: (i) The moisture sensor connects to a visual ( e.g., digital, graphic, analog) or auditory ( e.g., voice, pure tone) alarm that is readily detectable by the diver under the diving conditions in which the diver operates, and warns the diver of moisture in the breathing loop in sufficient time to terminate the dive and return safely to the surface; and (ii) Each diver uses the moisture sensor according to the rebreather manufacturer's instructions. (e) The employer must ensure that each rebreather contains a continuously functioning CO 2 sensor in the breathing loop, and that: (i) The rebreather manufacturer approves the location of the CO 2 sensor in the breathing loop; (ii) The CO 2 sensor is integrated with an alarm that operates in a visual ( e.g., digital, graphic, analog) or auditory ( e.g., voice, pure tone) mode that is readily detectable by each diver under the diving conditions in which the diver operates; and (iii) The CO 2 alarm remains continuously activated when the inhaled CO 2 level reaches and exceeds 0.005 atmospheres absolute (ATA). (f) Before each day's diving operations, and more often when necessary, the employer must calibrate the CO 2 sensor according to the sensor manufacturer's instructions, and ensure that: (i) The equipment and procedures used to perform this calibration are accurate to within 10% of a CO 2 concentration of 0.005 ATA or less; (ii) The equipment and procedures maintain this accuracy as required by the sensor manufacturer's instructions; and (iii) The calibration of the CO 2 sensor is accurate to within 10% of a CO 2 concentration of 0.005 ATA or less. (g) The employer must replace the CO 2 sensor when it fails to meet the accuracy requirements specified in paragraph 1(f)(iii) of this appendix, and ensure that the replacement CO 2 sensor meets the accuracy requirements specified in paragraph 1(f)(iii) of this appendix before placing the rebreather in operation. (h) As an alternative to using a continuously functioning CO 2 sensor, the employer may use a schedule for replacing CO 2 -sorbent material provided by the rebreather manufacturer. The employer may use such a schedule only when the rebreather manufacturer has developed it according to the canister-testing protocol specified below in Condition 11, and must use the canister within the temperature range for which the manufacturer conducted its scrubber canister tests following that protocol. Variations above or below the range are acceptable only after the manufacturer adds that lower or higher temperature to the protocol. (i) When using CO 2 -sorbent replacement schedules, the employer must ensure that each rebreather uses a manufactured ( i.e., commercially pre-packed), disposable scrubber cartridge containing a CO 2 -sorbent material that: (i) Is approved by the rebreather manufacturer; (ii) Removes CO 2 from the diver's exhaled gas; and (iii) Maintains the CO 2 level in the breathable gas ( i.e., the gas that a diver inhales directly from the regulator) below a partial pressure of 0.01 ATA. (j) As an alternative to manufactured, disposable scrubber cartridges, the employer may fill CO 2 scrubber cartridges manually with CO 2 -sorbent material when: (i) The rebreather manufacturer permits manual filling of scrubber cartridges; (ii) The employer fills the scrubber cartridges according to the rebreather manufacturer's instructions; (iii) The employer replaces the CO 2 -sorbent material using a replacement schedule developed under paragraph 1(h) of this appendix; and (iv) The employer demonstrates that manual filling meets the requirements specified in paragraph 1(i) of this appendix. (k) The employer must ensure that each rebreather has an information module that provides: (i) A visual ( e.g., digital, graphic, analog) or auditory ( e.g., voice, pure tone) display that effectively warns the diver of solenoid failure (when the rebreather uses solenoids) and other electrical weaknesses or failures ( e.g., low battery voltage); (ii) For a semi-closed circuit rebreather, a visual display for the partial pressure of CO 2 , or deviations above and below a preset CO 2 partial pressure of 0.005 ATA; and (iii) For a closed-circuit rebreather, a visual display for: partial pressures of O 2 and CO 2 , or deviations above and below a preset CO 2 partial pressure of 0.005 ATA and a preset O 2 partial pressure of 1.40 ATA or lower; gas temperature in the breathing loop; and water temperature. (l) Before each day's diving operations, and more often when necessary, the employer must ensure that the electrical power supply and electrical and electronic circuits in each rebreather are operating as required by the rebreather manufacturer's instructions. 2. Special Requirements for Closed-Circuit Rebreathers (a) The employer must ensure that each closed-circuit rebreather uses supply-pressure sensors for the O 2 and diluent ( i.e., air or nitrogen) gases and continuously functioning sensors for detecting temperature in the inhalation side of the gas-loop and the ambient water. (b) The employer must ensure that: (i) At least two O 2 sensors are located in the inhalation side of the breathing loop; and (ii) The O 2 sensors are: functioning continuously; temperature compensated; and approved by the rebreather manufacturer. (c) Before each day's diving operations, and more often when necessary, the employer must calibrate O 2 sensors as required by the sensor manufacturer's instructions. In doing so, the employer must: (i) Ensure that the equipment and procedures used to perform the calibration are accurate to within 1% of the O 2 fraction by volume; (ii) Maintain this accuracy as required by the manufacturer of the calibration equipment; (iii) Ensure that the sensors are accurate to within 1% of the O 2 fraction by volume; (iv) Replace O 2 sensors when they fail to meet the accuracy requirements specified in paragraph 2(c)(iii) of this appendix; and (v) Ensure that the replacement O 2 sensors meet the accuracy requirements specified in paragraph 2(c)(iii) of this appendix before placing a rebreather in operation. (d) The employer must ensure that each closed-circuit rebreather has: (i) A gas-controller package with electrically operated solenoid O 2 -supply valves; (ii) A pressure-activated regulator with a second-stage diluent-gas addition valve; (iii) A manually operated gas-supply bypass valve to add O 2 or diluent gas to the breathing loop; and (iv) Separate O 2 and diluent-gas cylinders to supply the breathing-gas mixture. 3. O 2 Concentration in the Breathing Gas The employer must ensure that the fraction of O 2 in the nitrox breathing-gas mixture: (a) Is greater than the fraction of O 2 in compressed air ( i.e., exceeds 22% by volume); (b) For open-circuit SCUBA, never exceeds a maximum fraction of breathable O 2 of 40% by volume or a maximum O 2 partial pressure of 1.40 ATA, whichever exposes divers to less O 2 ; and (c) For a rebreather, never exceeds a maximum O 2 partial pressure of 1.40 ATA. 4. Regulating O 2 Exposures and Diving Depth (a) Regarding O 2 exposure, the employer must: (i) Ensure that the exposure of each diver to partial pressures of O 2 between 0.60 and 1.40 ATA does not exceed the 24-hour single-exposure time limits specified either by the 2001 National Oceanic and Atmospheric Administration Diving Manual (the “2001 NOAA Diving Manual”), or by the report entitled “Enriched Air Operations and Resource Guide” published in 1995 by the Professional Association of Diving Instructors (known commonly as the “1995 DSAT Oxygen Exposure Table”); and (ii) Determine a diver's O 2 -exposure duration using the diver's maximum O 2 exposure (partial pressure of O 2 ) during the dive and the total dive time ( i.e., from the time the diver leaves the surface until the diver returns to the surface). (b) Regardless of the diving equipment used, the employer must ensure that no diver exceeds a depth of 130 feet of sea water (“fsw”) or a maximum O 2 partial pressure of 1.40 ATA, whichever exposes the diver to less O 2 . 5. Use of No-Decompression Limits (a) For diving conducted while using nitrox breathing-gas mixtures, the employer must ensure that each diver remains within the no-decompression limits specified for single and repetitive air diving and published in the 2001 NOAA Diving Manual or the report entitled “Development and Validation of No-Stop Decompression Procedures for Recreational Diving: The DSAT Recreational Dive Planner,” published in 1994 by Hamilton Research Ltd. (known commonly as the “1994 DSAT No-Decompression Tables”). (b) An employer may permit a diver to use a dive-decompression computer designed to regulate decompression when the dive-decompression computer uses the no-decompression limits specified in paragraph 5(a) of this appendix, and provides output that reliably represents those limits. 6. Mixing and Analyzing the Breathing Gas (a) The employer must ensure that: (i) Properly trained personnel mix nitrox-breathing gases, and that nitrogen is the only inert gas used in the breathing-gas mixture; and (ii) When mixing nitrox-breathing gases, they mix the appropriate breathing gas before delivering the mixture to the breathing-gas cylinders, using the continuous-flow or partial-pressure mixing techniques specified in the 2001 NOAA Diving Manual, or using a filter-membrane system. (b) Before the start of each day's diving operations, the employer must determine the O 2 fraction of the breathing-gas mixture using an O 2 analyzer. In doing so, the employer must: (i) Ensure that the O 2 analyzer is accurate to within 1% of the O 2 fraction by volume. (ii) Maintain this accuracy as required by the manufacturer of the analyzer. (c) When the breathing gas is a commercially supplied nitrox breathing-gas mixture, the employer must ensure that the O 2 meets the medical USP specifications (Type I, Quality Verification Level A) or aviator's breathing-oxygen specifications (Type I, Quality Verification Level E) of CGA G-4.3-2000 (“Commodity Specification for Oxygen”). In addition, the commercial supplier must: (i) Determine the O 2 fraction in the breathing-gas mixture using an analytic method that is accurate to within 1% of the O 2 fraction by volume; (ii) Make this determination when the mixture is in the charged tank and after disconnecting the charged tank from the charging apparatus; (iii) Include documentation of the O 2 -analysis procedures and the O 2 fraction when delivering the charged tanks to the employer. (d) Before producing nitrox breathing-gas mixtures using a compressor in which the gas pressure in any system component exceeds 125 pounds per square inch (psi), the: (i) Compressor manufacturer must provide the employer with documentation that the compressor is suitable for mixing high-pressure air with the highest O 2 fraction used in the nitrox breathing-gas mixture when operated according to the manufacturer's operating and maintenance specifications; (ii) Employer must comply with paragraph 6(e) of this appendix, unless the compressor is rated for O 2 service and is oil-less or oil-free; and (iii) Employer must ensure that the compressor meets the requirements specified in paragraphs (i)(1) and (i)(2) of § 1910.430 whenever the highest O 2 fraction used in the mixing process exceeds 40%. (e) Before producing nitrox breathing-gas mixtures using an oil-lubricated compressor to mix high-pressure air with O 2 , and regardless of the gas pressure in any system component, the: (i) Employer must use only uncontaminated air ( i.e., air containing no hydrocarbon particulates) for the nitrox breathing-gas mixture; (ii) Compressor manufacturer must provide the employer with documentation that the compressor is suitable for mixing the high-pressure air with the highest O 2 fraction used in the nitrox breathing-gas mixture when operated according to the manufacturer's operating and maintenance specifications; (iii) Employer must filter the high-pressure air to produce O 2 -compatible air; (iv) The filter-system manufacturer must provide the employer with documentation that the filter system used for this purpose is suitable for producing O 2 -compatible air when operated according to the manufacturer's operating and maintenance specifications; and (v) Employer must continuously monitor the air downstream from the filter for hydrocarbon contamination. (f) The employer must ensure that diving equipment using nitrox breathing-gas mixtures or pure O 2 under high pressure ( i.e., exceeding 125 psi) conforms to the O 2 -service requirements specified in paragraphs (i)(1) and (i)(2) of § 1910.430. 7. Emergency Egress (a) Regardless of the type of diving equipment used by a diver ( i.e., open-circuit SCUBA or rebreathers), the employer must ensure that the equipment contains (or incorporates) an open-circuit emergency-egress system (a “bail-out” system) in which the second stage of the regulator connects to a separate supply of emergency breathing gas, and the emergency breathing gas consists of air or the same nitrox breathing-gas mixture used during the dive. (b) As an alternative to the “bail-out” system specified in paragraph 7(a) of this appendix, the employer may use: (i) For open-circuit SCUBA, an emergency-egress system as specified in § 1910.424(c)(4); or (ii) For a semi-closed-circuit and closed-circuit rebreather, a system configured so that the second stage of the regulator connects to a reserve supply of emergency breathing gas. (c) The employer must obtain from the rebreather manufacturer sufficient information to ensure that the bail-out system performs reliably and has sufficient capacity to enable the diver to terminate the dive and return safely to the surface. 8. Treating Diving-Related Medical Emergencies (a) Before each day's diving operations, the employer must: (i) Verify that a hospital, qualified health-care professionals, and the nearest Coast Guard Coordination Center (or an equivalent rescue service operated by a state, county, or municipal agency) are available to treat diving-related medical emergencies; (ii) Ensure that each dive site has a means to alert these treatment resources in a timely manner when a diving-related medical emergency occurs; and (iii) Ensure that transportation to a suitable decompression chamber is readily available when no decompression chamber is at the dive site, and that this transportation can deliver the injured diver to the decompression chamber within four (4) hours travel time from the dive site. (b) The employer must ensure that portable O 2 equipment is available at the dive site to treat injured divers. In doing so, the employer must ensure that: (i) The equipment delivers medical-grade O 2 that meets the requirements for medical USP oxygen (Type I, Quality Verification Level A) of CGA G-4.3-2000 (“Commodity Specification for Oxygen”); (ii) The equipment delivers this O 2 to a transparent mask that covers the injured diver's nose and mouth; and (iii) Sufficient O 2 is available for administration to the injured diver from the time the employer recognizes the symptoms of a diving-related medical emergency until the injured diver reaches a decompression chamber for treatment. (c) Before each day's diving operations, the employer must: (i) Ensure that at least two attendants, either employees or non-employees, qualified in first-aid and administering O 2 treatment, are available at the dive site to treat diving-related medical emergencies; and (ii) Verify their qualifications for this task. 9. Diving Logs and No-Decompression Tables (a) Before starting each day's diving operations, the employer must: (i) Designate an employee or a non-employee to make entries in a diving log; and (ii) Verify that this designee understands the diving and medical terminology, and proper procedures, for making correct entries in the diving log. (b) The employer must: (i) Ensure that the diving log conforms to the requirements specified by paragraph (d) (“Record of dive”) of § 1910.423; and (ii) Maintain a record of the dive according to § 1910.440 (“Recordkeeping requirements”). (c) The employer must ensure that a hard-copy of the no-decompression tables used for the dives (as specified in paragraph 6(a) of this appendix) is readily available at the dive site, whether or not the divers use dive-decompression computers. 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 (a) The employer must ensure that the rebreather manufacturer has used the following procedures for determining that the CO 2 -sorbent material meets the specifications of the sorbent material's manufacturer: (i) The North Atlantic Treating Organization CO 2 absorbent-activity test; (ii) The RoTap shaker and nested-sieves test; (iii) The Navy Experimental Diving Unit (“NEDU”)-derived Schlegel test; and (iv) The NEDU MeshFit software. (b) The employer must ensure that the rebreather manufacturer has applied the following canister-testing materials, methods, procedures, and statistical analyses: (i) Use of a nitrox breathing-gas mixture that has an O 2 fraction maintained at 0.28 (equivalent to 1.4 ATA of O 2 at 130 fsw, the maximum O 2 concentration permitted at this depth); (ii) While operating the rebreather at a maximum depth of 130 fsw, use of a breathing machine to continuously ventilate the rebreather with breathing gas that is at 100% humidity and warmed to a temperature of 98.6 degrees F (37 degrees C) in the heating-humidification chamber; (iii) Measurement of the O 2 concentration of the inhalation breathing gas delivered to the mouthpiece; (iv) Testing of the canisters using the three ventilation rates listed in Table I below (with the required breathing-machine tidal volumes and frequencies, and CO 2 -injection rates, provided for each ventilation rate): Table I—Canister Testing Parameters 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). (v) When using a work rate ( i.e., breathing-machine tidal volume and frequency) other than the work rates listed in the table above, addition of the appropriate combinations of ventilation rates and CO 2 -injection rates; (vi) Performance of the CO 2 injection at a constant (steady) and continuous rate during each testing trial; (vii) Determination of canister duration using a minimum of four (4) water temperatures, including 40, 50, 70, and 90 degrees F (4.4, 10.0, 21.1, and 32.2 degrees C, respectively); (viii) Monitoring of the breathing-gas temperature at the rebreather mouthpiece (at the “chrome T” connector), and ensuring that this temperature conforms to the temperature of a diver's exhaled breath at the water temperature and ventilation rate used during the testing trial; 1 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. (ix) Implementation of at least eight (8) testing trials for each combination of temperature and ventilation-CO 2 -injection rates (for example, eight testing trials at 40 degrees F using a ventilation rate of 22.5 Lpm at a CO 2 -injection rate of 0.90 Lpm); (x) Allowing the water temperature to vary no more than ±2.0 degrees F (±1.0 degree C) between each of the eight testing trials, and no more than ±1.0 degree F (±0.5 degree C) within each testing trial; (xi) Use of the average temperature for each set of eight testing trials in the statistical analysis of the testing-trial results, with the testing-trial results being the time taken for the inhaled breathing gas to reach 0.005 ATA of CO 2 ( i.e., the canister-duration results); (xii) Analysis of the canister-duration results using the repeated-measures statistics described in NEDU Report 2-99; (xiii) Specification of the replacement schedule for the CO 2 -sorbent materials in terms of the lower prediction line (or limit) of the 95% confidence interval; and (xiv) Derivation of replacement schedules only by interpolating among, but not by extrapolating beyond, the depth, water temperatures, and exercise levels used during canister testing. [69 FR 7363, Feb. 17, 2004]
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:
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.
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.
[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.
[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.
E = (C a T a + C b T b + . . .C n T n ) ÷ 8
E m = (C 1 ÷ L 1 + C 2 ÷ L 2 ) + . . .(C n ÷ L n )
Substance Actual concentration of 8-hour exposure (ppm) 8-hour TWA PEL (ppm) B 500 1,000 C 45 200 D 40 200
Table Z-1—Limits for Air Contaminants 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.
Table Z-2 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.
Table Z-3—Mineral Dusts 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-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.
Table 1 to § 1910.1001—Frequency of Chest X-ray 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.
Counts for the Fibers in the Figure 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.
[51 FR 22733, June 20, 1986]
Editorial Note: For Federal Register citations affecting § 1910.1001, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.
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]
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.
[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]
[39 FR 35896, Oct. 4, 1974. Redesignated at 40 FR 23072, May 28, 1975]
Editorial Note: For Federal Register citations affecting § 1910.1017, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.
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).
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.
[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]
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).
[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]
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.
DANGER
CONTAINS BERYLLIUM
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
AVOID CREATING DUST
DO NOT GET ON SKIN
[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]
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.
Table I 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.
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.
[43 FR 53007, Nov. 14, 1978]
Editorial Note: For Federal Register citations affecting § 1910.1025, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.
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.
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)-(12) of this section or, if multiple physician review under paragraph (l)(13) of this section or the alternative physician determination under paragraph (l)(14) of this section is invoked, it is the final, written medical finding, recommendation or determination that emerges from that process.
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.
Table I—Separate Engineering Control Airborne Limits (SECALs) for Processes in Selected Industries 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).
[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]
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.
[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]
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.
[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]
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
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).
[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]
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.
[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]
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.
[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]
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.
[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]
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.
[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]
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.
[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]
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.
[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]
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.
Table 1—Minimum Requirements for Respiratory Protection for Airborne BD 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.
[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:
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.
Table 1—Initial Determination Exposure Scenarios and Their Associated Monitoring Frequencies 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.
[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]
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.
[81 FR 16862, Mar. 25, 2016]
Table G-17—Neutron Flux Dose Equivalents 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
Table G-18 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
Figure G-10
[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.
[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]
[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:
[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]
[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]
[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]
[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.
[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:
[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]
[58 FR 35083, June 30, 1993]
[58 FR 35083, June 30, 1993]
[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]
Table D-1 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.
[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]
Table D-2—Permissible Noise Exposures 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
If the value of F e exceeds unity (1) the exposure exceeds permissible levels.
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]
Table 1 to § 1926.55—Permissible Exposure Limits for Airborne Contaminants 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
Table 2 to § 1926.55—Mineral Dusts 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]
Table D-3—Minimum Illumination Intensities in Foot-Candles 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.
Table D-57.1—Grinding and Abrasive Cutting-Off Wheels 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: If wheel width = 4 1/2 inches (11.43 cm), then 4.5 ÷ 4 × 610 = 686 (rounded to 690).
Table D-57.2—Buffing and Polishing Wheels 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
Table D-57.3—Horizontal Single-Spindle Disc Grinder 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
Table D-57.4—Horizontal Double-Spindle Disc Grinder 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
Table D-57.5—Vertical Spindle Disc Grinder 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.
Table D-57.6—Grinding and Polishing Belts 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
Figure D-57.1—Vertical Spindle Disc Grinder Exhaust Hood and Branch Pipe Connections
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.
Figure D-57.2—Standard Grinder Hood
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.
Figure D-57.3—A Method of Applying an Exhaust Enclosure to Swing-Frame Grinders
Figure D-57.4
Standard Buffing and Polishing Hood 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.
Figure D-57.5—Cradle Polishing or Grinding Enclosure
Entry loss = 0.45 velocity pressure for tapered takeoff
Figure D-57.6—Horizontal Single-Spindle Disc Grinder Exhaust Hood and Branch Pipe Connections
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.
Figure D-57.7—Horizontal Double-Spindle Disc Grinder Exhaust Hood and Branch Pipe Connections
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.
Figure D-57.8—A Typical Hood for a Belt Operation
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.
Table D-57.7—Minimum Maintained Velocities Into Spray Booths 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. (1) LEL of toluene from Table D-57.8, column 2, is 1.4 percent. (2) Cubic feet of vapor per gallon from Table D-57.8, column 1, is 30.4 cubic feet per gallon. (3) Dilution volume required = 4 (100-1.4) 30.4 ÷ 1.4 = 8,564 cubic feet. (4) To convert to cubic feet per minute of required ventilation, multiply the dilution volume required per gallon of solvent by the number of gallons of solvent evaporated per minute.
Table D-57.8—Lower Explosive Limit of Some Commonly Used Solvents 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).
Note A:
Where:
c = Concentration measured at the operation in p.p.m.
Table D-57.9—Determination of Hazard Potential 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)
Table D-57.10—Determination of Rate of Gas, Vapor, or Mist Evolution 1 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.
Table D-57.11—Control Velocities in Feet Per Minute (f.p.m.) for Undisturbed Locations 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.
Table D-57.12—Minimum Ventilation Rate in Cubic Feet of Air Per Minute Per Square Foot of Tank Area for Lateral Exhaust 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.
[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]
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.
[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]
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.
Allowable employee exposure (in µg/m 3 ) = 400 divided by hours worked in the day.
[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]
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:
Hazardous waste means—(A) A waste or combination of wastes as defined in 40 CFR 261.3, or
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.
Table D-65.1—Minimum Illumination Intensities in Foot-Candles 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.
Table D-65.2—Toilet Facilities 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.
[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]
( 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)
[58 FR 35149, June 30, 1993]
[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]
Table E-1—AC Proof-Test Requirements 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
Table E-2—DC Proof-Test Requirements 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.
Table E-3—Glove Tests—Water Level 1 2 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.).
Table E-4—Rubber Insulating Equipment, Voltage Requirements 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.
Table E-5—Rubber Insulating Equipment, Test Intervals 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]
[44 FR 8577, Feb. 9, 1979, as amended at 77 FR 37600, June 22, 2012; 77 FR 42988, July 23, 2012]
Table E-1—Filter Lens Shade Numbers for Protection Against Radiant Energy 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
Table E-2—Selecting Laser Safety Glass 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]
[44 FR 8577, Feb. 9, 1979]
[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]
Table F-2 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.
This paragraph may be used for operating pressures not exceeding 1 p.s.i.g.
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.)
Table F-10—Wetted Area Versus Cubic Feet (Meters) Free Air Per Hour [14.7 psia and 60 °F. (15.55 °C)] 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 = 1,107 A 0.82
V = 1337 ÷ L √ M
Table F-11—Vent Line Diameters 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.
[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]
Table F-3 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
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.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35170, June 30, 1993]
Table F-4 Heating appliances Minimum clearance, (inches) Sides Rear Chimney connector Room heater, circulating type 12 12 18 Room heater, radiant type 36 36 18
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 77 FR 17894, Mar. 26, 2012]
[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]
[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]
[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]
Table H-1—Maximum Allowable Wear at any Point of Link 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
Table H-2—Number and Spacing of U-Bolt Wire Rope Clips 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]
[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]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35175, June 30, 1993]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35175, June 30, 1993]
[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]
[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]
[58 FR 35176, June 30, 1993]
[58 FR 35176, June 30, 1993, as amended at 69 FR 31882, June 8, 2004]
[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]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 51 FR 25318, July 11, 1986]
[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:
Table K-1—Working Clearances 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.
Table K-2—Minimum Depth of Clear Working Space in Front of Electric Equipment 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.
Table K-3—Elevation of Unguarded Energized Parts Above Working Space 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.
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996]
Table K-4—Receptacle Ratings for Various Size Circuits Circuit rating amperes Receptacle rating amperes 15 Not over 15. 20 15 or 20. 30 30. 40 40 or 50. 50 50.
[51 FR 25318, July 11, 1986, as amended at 54 FR 24334, June 7, 1989; 61 FR 5510, Feb. 13, 1996]
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996; 85 FR 8736, Feb. 18, 2020]
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.
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996]
[51 FR 25318, July 11, 1986, as amended at 61 FR 5510, Feb. 13, 1996]
[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]
[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.
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 —(a) (600 volts nominal, or less.) A device designed to open and close a circuit by nonautomatic means and to open the circuit automatically on a predetermined overcurrent without injury 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 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) Bare. A conductor having no covering or electrical insulation whatsoever.
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 —(a) Damp 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.
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) General-use 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.
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.”
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.
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.
[61 FR 46104, Aug. 30, 1996, as amended at 85 FR 8736, Feb. 18, 2020]
[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.
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]
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.
The following training provisions supplement and clarify the requirements of § 1926.21 regarding the hazards addressed in subpart M of this part.
Appendix A to Subpart M of Part 1926—Determining Roof Widths Non-Mandatory Guidelines for Complying With § 1926.501(b)(10) (1) This appendix serves as a guideline to assist employers complying with the requirements of § 1926.501(b)(10). Section 1926.501(b)(10) allows the use of a safety monitoring system alone as a means of providing fall protection during the performance of roofing operations on low-sloped roofs 50 feet (15.25 m) or less in width. Each example in the appendix shows a roof plan or plans and indicates where each roof or roof area is to be measured to determine its width. Section views or elevation views are shown where appropriate. Some examples show “correct” and “incorrect” subdivisions of irregularly shaped roofs divided into smaller, regularly shaped areas. In all examples, the dimension selected to be the width of an area is the lesser of the two primary dimensions of the area, as viewed from above. Example A shows that on a simple rectangular roof, width is the lesser of the two primary overall dimensions. This is also the case with roofs which are sloped toward or away from the roof center, as shown in Example B. (2) Many roofs are not simple rectangles. 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. (3) Roofs which are comprised of several separate, non-contiguous roof areas, as in Example D, may be considered as a series of individual roofs. Some roofs have penthouses, additional floors, courtyard openings, or similar architectural features; Example E shows how the rule for dividing roofs into subareas is applied to such configurations. Irregular, non-rectangular roofs must be considered on an individual basis, as shown in Example F. [85 FR 8738, Feb. 18, 2020]
Appendix B to Subpart M of Part 1926—Guardrail Systems 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. (1) For wood railings: 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. (2) For pipe railings: 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. (3) For structural steel railings: 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.
Appendix C to Subpart M of Part 1926—Personal Fall Arrest Systems Non-Mandatory Guidelines for Complying With § 1926.502(d) I. Test methods for personal fall arrest systems and positioning device systems —(a) General. 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. (b) General conditions for all tests in the appendix to § 1926.502(d). (1) Lifelines, lanyards and deceleration devices should be attached to an anchorage and connected to the body-belt or body harness in the same manner as they would be when used to protect employees. (2) The anchorage should be rigid, and should not have a deflection greater than 0.04 inches (1 mm) when a force of 2,250 pounds (10 kN) is applied. (3) The frequency response of the load measuring instrumentation should be 500 Hz. (4) The test weight used in the strength and force tests should be a rigid, metal, cylindrical or torso-shaped object with a girth of 38 inches plus or minus 4 inches (96 cm plus or minus 10 cm). (5) The lanyard or lifeline used to create the free fall distance should be supplied with the system, or in its absence, the least elastic lanyard or lifeline available to be used with the system. (6) The test weight for each test should be hoisted to the required level and should be quickly released without having any appreciable motion imparted to it. (7) The system's performance should be evaluated taking into account the range of environmental conditions for which it is designed to be used. (8) Following the test, the system need not be capable of further operation. (c) Strength test. (1) During the testing of all systems, a test weight of 300 pounds plus or minus 5 pounds (135 kg plus or minus 2.5 kg) should be used. (See paragraph (b)(4) of this section.) (2) The test consists of dropping the test weight once. A new unused system should be used for each test. (3) For lanyard systems, the lanyard length should be 6 feet plus or minus 2 inches (1.83 m plus or minus 5 cm) as measured from the fixed anchorage to the attachment on the body belt or body harness. (4) For rope-grab-type deceleration systems, the length of the lifeline above the centerline of the grabbing mechanism to the lifeline's anchorage point should not exceed 2 feet (0.61 m). (5) For lanyard systems, for systems with deceleration devices which do not automatically limit free fall distance to 2 feet (0.61 m) or less, and for systems with deceleration devices which have a connection distance in excess of 1 foot (0.3 m) (measured between the centerline of the lifeline and the attachment point to the body belt or harness), the test weight should be rigged to free fall a distance of 7.5 feet (2.3 m) from a point that is 1.5 feet (.46 m) above the anchorage point, to its hanging location (6 feet below the anchorage). The test weight should fall without interference, obstruction, or hitting the floor or ground during the test. In some cases a non-elastic wire lanyard of sufficient length may need to be added to the system (for test purposes) to create the necessary free fall distance. (6) For deceleration device systems with integral lifelines or lanyards which automatically limit free fall distance to 2 feet (0.61 m) or less, the test weight should be rigged to free fall a distance of 4 feet (1.22 m). (7) Any weight which detaches from the belt or harness has failed the strength test. (d) Force test —(1) General. 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. (2) For lanyard systems. (i) A test weight of 220 pounds plus or minus 3 pounds (100 kg plus or minus 1.6 kg) should be used. (See paragraph (b)(4) of this appendix). (ii) Lanyard length should be 6 feet plus or minus two inches (1.83 m plus or minus 5 cm) as measured from the fixed anchorage to the attachment on the body belt or body harness. (iii) The test weight should fall free from the anchorage level to its hanging location (a total of 6 feet (1.83 m) free fall distance) without interference, obstruction, or hitting the floor or ground during the test. (3) For all other systems. (i) A test weight of 220 pounds plus or minus 3 pounds (100 kg plus or minus 1.6 kg) should be used. (See paragraph (b)(4) of this appendix) (ii) The free fall distance to be used in the test should be the maximum fall distance physically permitted by the system during normal use conditions, up to a maximum free fall distance for the test weight of 6 feet (1.83 m), except as follows: (A) For deceleration systems which have a connection link or lanyard, the test weight should free fall a distance equal to the connection distance (measured between the centerline of the lifeline and the attachment point to the body belt or harness). (B) For deceleration device systems with integral lifelines or lanyards which automatically limit free fall distance to 2 feet (0.61 m) or less, the test weight should free fall a distance equal to that permitted by the system in normal use. (For example, to test a system with a self-retracting lifeline or lanyard, the test weight should be supported and the system allowed to retract the lifeline or lanyard as it would in normal use. The test weight would then be released and the force and deceleration distance measured). (4) A system fails the force test if the recorded maximum arresting force exceeds 1,260 pounds (5.6 kN) when using a body belt, and/or exceeds 2,520 pounds (11.2 kN) when using a body harness. (5) The maximum elongation and deceleration distance should be recorded during the force test. (e) Deceleration device tests —(1) General. 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. (2) Rope-grab-type deceleration devices. (i) Devices should be moved on a lifeline 1,000 times over the same length of line a distance of not less than 1 foot (30.5 cm), and the mechanism should lock each time. (ii) Unless the device is permanently marked to indicate the type(s) of lifeline which must be used, several types (different diameters and different materials), of lifelines should be used to test the device. (3) Other self-activating-type deceleration devices. 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. (a) Selection and use considerations. (1) The kind of personal fall arrest system selected should match the particular work situation, and any possible free fall distance should be kept to a minimum. Consideration should be given to the particular work environment. For example, the presence of acids, dirt, moisture, oil, grease, etc., and their effect on the system, should be evaluated. Hot or cold environments may also have an adverse effect on the system. Wire rope should not be used where an electrical hazard is anticipated. As required by the standard, the employer must plan to have means available to promptly rescue an employee should a fall occur, since the suspended employee may not be able to reach a work level independently. (2) Where lanyards, connectors, and lifelines are subject to damage by work operations such as welding, chemical cleaning, and sandblasting, the component should be protected, or other securing systems should be used. The employer should fully evaluate the work conditions and environment (including seasonal weather changes) before selecting the appropriate personal fall protection system. Once in use, the system's effectiveness should be monitored. In some cases, a program for cleaning and maintenance of the system may be necessary. (b) Testing considerations. 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. (c) Component compatibility considerations. 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. (d) Employee training considerations. 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. (e) Instruction considerations. Employers should obtain comprehensive instructions from the supplier as to the system's proper use and application, including, where applicable: (1) The force measured during the sample force test; (2) The maximum elongation measured for lanyards during the force test; (3) The deceleration distance measured for deceleration devices during the force test; (4) Caution statements on critical use limitations; (5) Application limits; (6) Proper hook-up, anchoring and tie-off techniques, including the proper dee-ring or other attachment point to use on the body belt and harness for fall arrest; (7) Proper climbing techniques; (8) Methods of inspection, use, cleaning, and storage; and (9) Specific lifelines which may be used. This information should be provided to employees during training. (f) Rescue considerations. 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. (g) Inspection considerations. 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. (h) Tie-off considerations. (1) One of the most important aspects of personal fall protection systems is fully planning the system before it is put into use. Probably the most overlooked component is planning for suitable anchorage points. Such planning should ideally be done before the structure or building is constructed so that anchorage points can be incorporated during construction for use later for window cleaning or other building maintenance. If properly planned, these anchorage points may be used during construction, as well as afterwards. (i) Properly planned anchorages should be used if they are available. In some cases, anchorages must be installed immediately prior to use. In such cases, a registered professional engineer with experience in designing fall protection systems, or another qualified person with appropriate education and experience should design an anchor point to be installed. (ii) In other cases, the Agency recognizes that there will be a need to devise an anchor point from existing structures. Examples of what might be appropriate anchor points are steel members or I-beams if an acceptable strap is available for the connection (do not use a lanyard with a snaphook clipped onto itself); large eye-bolts made of an appropriate grade steel; guardrails or railings if they have been designed for use as an anchor point; or masonry or wood members only if the attachment point is substantial and precautions have been taken to assure that bolts or other connectors will not pull through. A qualified person should be used to evaluate the suitable of these “make shift” anchorages with a focus on proper strength. (2) 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 which does not reduce the strength of the system (such as a properly dimensioned eye-bolt/snap-hook anchorage). Therefore, if a means of attachment is used that will reduce the strength of the system, that component should be replaced by a stronger one, but one that will also maintain the appropriate maximum arrest force characteristics. (3) Tie-off using a knot in a rope lanyard or lifeline (at any location) can reduce the lifeline or lanyard strength by 50 percent or more. Therefore, a stronger lanyard or lifeline should be used to compensate for the weakening effect of the knot, or the lanyard length should be reduced (or the tie-off location raised) to minimize free fall distance, or the lanyard or lifeline should be replaced by one which has an appropriately incorporated connector to eliminate the need for a knot. (4) Tie-off of a rope lanyard or lifeline around an “H” or “I” beam or similar support can reduce its strength as much as 70 percent due to the cutting action of the beam edges. Therefore, use should be made of a webbing lanyard or wire core lifeline around the beam; or the lanyard or lifeline should be protected from the edge; or free fall distance should be greatly minimized. (5) Tie-off where the line passes over or around rough or sharp surfaces reduces strength drastically. Such a tie-off should be avoided or an alternative tie-off rigging should be used. Such alternatives may include use of a snap-hook/dee ring connection, wire rope tie-off, an effective padding of the surfaces, or an abrasion-resistance strap around or over the problem surface. (6) Horizontal lifelines may, depending on their geometry and angle of sag, 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. The reason for this is that in multiple tie-offs to a horizontal lifeline, if one employee falls, the movement of the falling employee and the horizontal lifeline during arrest of the fall may cause other employees to fall also. Horizontal lifeline and anchorage strength should be increased for each additional employee to be tied off. For these and other reasons, the design of systems using horizontal lifelines must only be done by qualified persons. Testing of installed lifelines and anchors prior to use is recommended. (7) The strength of an eye-bolt is rated along the axis of the bolt and its strength is greatly reduced if the force is applied at an angle to this axis (in the direction of shear). Also, care should be exercised in selecting the proper diameter of the eye to avoid accidental disengagement of snap-hooks not designed to be compatible for the connection. (8) Due to the significant reduction in the strength of the lifeline/lanyard (in some cases, as much as a 70 percent reduction), the sliding hitch knot (prusik) should not be used for lifeline/lanyard connections except in emergency situations where no other available system is practical. 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” knot (preferable) may be used in emergency situations; however, care should be taken to limit free fall distance to a minimum because of reduced lifeline/lanyard strength. (i) Vertical lifeline considerations. 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. (j) Snap-hook considerations. (1) Although not required by this standard for all connections until January 1, 1998, locking snaphooks designed for connection to suitable objects (of sufficient strength) are highly recommended in lieu of the nonlocking type. Locking snaphooks incorporate a positive locking mechanism in addition to the spring loaded keeper, which will not allow the keeper to open under moderate pressure without someone first releasing the mechanism. Such a feature, properly designed, effectively prevents roll-out from occurring. (2) As required by § 1926.502(d)(6), the following connections must be avoided (unless properly designed locking snaphooks are used) because they are conditions which can result in roll-out when a nonlocking snaphook is used: (i) Direct connection of a snaphook to a horizontal lifeline. (ii) Two (or more) snaphooks connected to one dee-ring. (iii) Two snaphooks connected to each other. (iv) A snaphook connected back on its integral lanyard. (v) A snaphook connected to a webbing loop or webbing lanyard. (vi) Improper dimensions of the dee-ring, rebar, or other connection point in relation to the snaphook dimensions which would allow the snaphook keeper to be depressed by a turning motion of the snaphook. (k) Free fall considerations. 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. (l) Elongation and deceleration distance considerations. 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. (m) Obstruction considerations. 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. (n) Other considerations. 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.
Appendix D to Subpart M of Part 1926—Positioning Device Systems 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. (a) General. (1) Single strap positioning devices shall have one end attached to a fixed anchorage and the other end connected to a body belt or harness in the same manner as they would be used to protect employees. Double strap positioning devices, similar to window cleaner's belts, shall have one end of the strap attached to a fixed anchorage and the other end shall hang free. The body belt or harness shall be attached to the strap in the same manner as it would be used to protect employees. The two strap ends shall be adjusted to their maximum span. (2) The fixed anchorage shall be rigid, and shall not have a deflection greater than .04 inches (1 mm) when a force of 2,250 pounds (10 kN) is applied. (3) During the testing of all systems, a test weight of 250 pounds plus or minus 3 pounds (113 kg plus or minus 1.6 kg) shall be used. The weight shall be a rigid object with a girth of 38 inches plus or minus 4 inches (96 cm plus or minus 10 cm). (4) Each test shall consist of dropping the specified weight one time without failure of the system being tested. A new system shall be used for each test. (5) The test weight for each test shall be hoisted exactly 4 feet (1.2 m above its “at rest” position), and shall be dropped so as to permit a vertical free fall of 4 feet (1.2 m). (6) The test is failed whenever any breakage or slippage occurs which permits the weight to fall free of the system. (7) Following the test, the system need not be capable of further operation; however, all such incapacities shall be readily apparent. 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.
Appendix E to Subpart M of Part 1926—Sample Fall Protection Plan 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 (Company Name) is dedicated to the protection of its employees from on-the-job injuries. All employees of (Company Name) have the responsibility to work safely on the job. The purpose of this plan is: (a) To supplement our standard safety policy by providing safety standards specifically designed to cover fall protection on this job and; (b) to ensure that each employee is trained and made aware of the safety provisions which are to be implemented by this plan prior to the start of erection. 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: (a) Cranes (1) Operator error. (2) Site conditions (soft or unstable ground). (3) Mechanical failure. (4) Structural failure. (5) Rigging failure. (6) Crane signal/radio communication failure. (b) Weather Conditions (1) Wind (strong wind/sudden gusting)—particularly a problem with the large surface areas of precast concrete members. (2) Snow/rain (visibility). (3) Fog (visibility). (4) Cold—causing slowed reactions or mechanical problems. (c) Structure/Product Conditions. (1) Lifting Eye failure. (2) Bearing failure or slippage. (3) Structure shifting. (4) Bracing failure. (5) Product failure. (d) Human Error. (1) Incorrect tag line procedure. (2) Tag line hang-up. (3) Incorrect or misunderstood crane signals. (4) Misjudged elevation of member. (5) Misjudged speed of member. (6) Misjudged angle of member. 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. (a) Temporary structural supports, installed to provide attaching points for lifelines limit the space which is essential for orderly positioning, alignment and placement of the precast concrete members. To keep the lanyards a reasonable and manageable length, lifeline supports would necessarily need to be in proximity to the positioning process. A sudden shift of the precast concrete member being positioned because of wind pressure or crane movement could make it strike the temporary supporting structure, moving it suddenly and causing tied off employees to fall. (b) The time in manhours which would be expended in placing and maintaining temporary structural supports for lifeline attaching points could exceed the expended manhours involved in placing the precast concrete members. No protection could be provided for the employees erecting the temporary structural supports and these supports would have to be moved for each successive step in the construction process, thus greatly increasing the employee's exposure to the fall hazard. (c) The use of a cable strung horizontally between two columns to provide tie off lines for erecting or walking a beam for connecting work is not feasible and creates a greater hazard on this multi-story building for the following reasons: (1) If a connector is to use such a line, it must be installed between the two columns. To perform this installation requires an erector to have more fall exposure time attaching the cable to the columns than would be spent to make the beam to column connection itself. (2) If such a line is to be installed so that an erector can walk along a beam, it must be overhead or below him. For example, if a connector must walk along a 24 in. wide beam, the presence of a line next to the connector at waist level, attached directly to the columns, would prevent the connector from centering their weight over the beam and balancing themselves. Installing the line above the connector might be possible on the first level of a two-story column; however, the column may extend only a few feet above the floor level at the second level or be flush with the floor level. Attaching the line to the side of the beam could be a solution; however, it would require the connector to attach the lanyard below foot level which would most likely extend a fall farther than 6 ft. (3) When lines are strung over every beam, it becomes more and more difficult for the crane operator to lower a precast concrete member into position without the member becoming fouled. Should the member become entangled, it could easily dislodge the line from a column. If a worker is tied to it at the time, a fall could be caused. 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 (Insert Company Name) 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 (Your company name here) is dedicated to the protection of its employees from on-the-job injuries. All employees of (Your company name here) have the responsibility to work safely on the job. The purpose of the plan is to supplement our existing safety and health program and to ensure that every employee who works for (Your company name here) recognizes workplace fall hazards and takes the appropriate measures to address those hazards. 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. (Your company name here) shall take the following steps to ensure that the CAZ is clearly marked or controlled by the competent person: • 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. (Your company name here) shall take the following steps to protect workers who are exposed to fall hazards while working from the top plate installing trusses/rafters: • 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. (Your company name here) shall take the following steps to protect workers who are exposed to fall hazards while securing trusses/rafters at the peak of the trusses/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. (Your company name here) shall take the following steps to protect workers who are exposed to fall hazards while installing roof 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]
Minimum Factors of Safety for Suspension Wire Ropes 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]
[44 FR 8577, Feb. 9, 1979, as amended at 75 FR 48134, Aug. 9, 2010]
[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]
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.
[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]
[39 FR 22801, June 24, 1974, as amended at 42 FR 37674, July 22, 1977]
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.
[54 FR 45959, Oct. 31, 1989, as amended at 59 FR 40730, Aug. 9, 1994]
Appendix A to Subpart P of Part 1926—Soil Classification (a) Scope and application —(1) Scope. 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. (2) Application. 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. (b) Definitions. 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: (i) The soil is fissured; or (ii) The soil is subject to vibration from heavy traffic, pile driving, or similar effects; or (iii) The soil has been previously disturbed; or (iv) The soil is part of a sloped, layered system where the layers dip into the excavation on a slope of four horizontal to one vertical (4H:1V) or greater; or (v) The material is subject to other factors that would require it to be classified as a less stable material. Type B means: (i) Cohesive soil with an unconfined compressive strength greater than 0.5 tsf (48 kPa) but less than 1.5 tsf (144 kPa); or (ii) Granular cohesionless soils including: angular gravel (similar to crushed rock), silt, silt loam, sandy loam and, in some cases, silty clay loam and sandy clay loam. (iii) Previously disturbed soils except those which would otherwise be classified as Type C soil. (iv) Soil that meets the unconfined compressive strength or cementation requirements for Type A, but is fissured or subject to vibration; or (v) Dry rock that is not stable; or (vi) Material that is part of a sloped, layered system where the layers dip into the excavation on a slope less steep than four horizontal to one vertical (4H:1V), but only if the material would otherwise be classified as Type B. Type C means: (i) Cohesive soil with an unconfined compressive strength of 0.5 tsf (48 kPa) or less; or (ii) Granular soils including gravel, sand, and loamy sand; or (iii) Submerged soil or soil from which water is freely seeping; or (iv) Submerged rock that is not stable; or (v) Material in a sloped, layered system where the layers dip into the excavation on a slope of four horizontal to one vertical (4H:1V) or steeper. 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. (c) Requirements —(1) Classification of soil and rock deposits. 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. (2) Basis of classification. 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. (3) Visual and manual analyses. 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. (4) Layered systems. 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. (5) Reclassification. 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. (d) Acceptable visual and manual tests —(1) Visual tests. 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. (i) Observe samples of soil that are excavated and soil in the sides of the excavation. Estimate the range of particle sizes and the relative amounts of the particle sizes. Soil that is primarily composed of fine-grained material is cohesive material. Soil composed primarily of coarse-grained sand or gravel is granular material. (ii) Observe soil as it is excavated. Soil that remains in clumps when excavated is cohesive. Soil that breaks up easily and does not stay in clumps is granular. (iii) Observe the side of the opened excavation and the surface area adjacent to the excavation. Crack-like openings such as tension cracks could indicate fissured material. If chunks of soil spall off a vertical side, the soil could be fissured. Small spalls are evidence of moving ground and are indications of potentially hazardous situations. (iv) Observe the area adjacent to the excavation and the excavation itself for evidence of existing utility and other underground structures, and to identify previously disturbed soil. (v) Observe the opened side of the excavation to identify layered systems. Examine layered systems to identify if the layers slope toward the excavation. Estimate the degree of slope of the layers. (vi) Observe the area adjacent to the excavation and the sides of the opened excavation for evidence of surface water, water seeping from the sides of the excavation, or the location of the level of the water table. (vii) Observe the area adjacent to the excavation and the area within the excavation for sources of vibration that may affect the stability of the excavation face. (2) Manual tests. 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. (i) Plasticity. 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. (ii) Dry strength. 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. (iii) Thumb penetration. 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. (iv) Other strength tests. Estimates of unconfined compressive strength of soils can also be obtained by use of a pocket penetrometer or by using a hand-operated shearvane. (v) Drying test. 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: (A) If the sample develops cracks as it dries, significant fissures are indicated. (B) Samples that dry without cracking are to be broken by hand. If considerable force is necessary to break a sample, the soil has significant cohesive material content. The soil can be classified as an unfissured cohesive material and the unconfined compressive strength should be determined. (C) If a sample breaks easily by hand, it is either a fissured cohesive material or a granular material. To distinguish between the two, pulverize the dried clumps of the sample by hand or by stepping on them. If the clumps do not pulverize easily, the material is cohesive with fissures. If they pulverize easily into very small fragments, the material is granular. [85 FR 8743, Feb. 18, 2020]
Appendix B to Subpart P of Part 1926—Sloping and Benching (a) Scope and application. 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). (b) Definitions. 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. (c) Requirements —(1) Soil classification. Soil and rock deposits shall be classified in accordance with appendix A to subpart P of part 1926. (2) Maximum allowable slope. The maximum allowable slope for a soil or rock deposit shall be determined from Table B-1 of this appendix. (3) Actual slope. (i) The actual slope shall not be steeper than the maximum allowable slope. (ii) The actual slope shall be less steep than the maximum allowable slope, when there are signs of distress. If that situation occurs, the slope shall be cut back to an actual slope which is at least 1/2 horizontal to one vertical ( 1/2 H:1V) less steep than the maximum allowable slope. (iii) When surcharge loads from stored material or equipment, operating equipment, or traffic are present, a competent person shall determine the degree to which the actual slope must be reduced below the maximum allowable slope, and shall assure that such reduction is achieved. Surcharge loads from adjacent structures shall be evaluated in accordance with § 1926.651(i). (4) Configurations. Configurations of sloping and benching systems shall be in accordance with Figure B-1. Figure B-1 Slope Configurations (All slopes stated below are in the horizontal to vertical ratio) 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. Simple Slope—General 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. Simple Slope—Short Term 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: Simple Bench Multiple Bench 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. Unsupported Vertically Sided Lower Portion—Maximum 8 Feet in Depth 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. Unsupported Vertically Sided Lower Portion—Maximum 12 Feet in Depth 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. Supported or Shielded Vertically Sided Lower Portion 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. Simple Slope 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: Single Bench Multiple Bench 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. Vertically Sided Lower Portion 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. Simple Slope 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. Vertical Sided Lower Portion 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. 2. All other sloped excavations shall be in accordance with the other options permitted in § 1926.652(b).
Appendix C to Subpart P of Part 1926—Timber Shoring for Trenches (a) Scope. 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). (b) Soil Classification. 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. (c) Presentation of Information. Information is presented in several forms as follows: (1) Information is presented in tabular form in Tables C-1.1, C-1.2, and C-1.3, and Tables C-2.1, C-2.2 and C-2.3 following paragraph (g) of the appendix. Each table presents the minimum sizes of timber members to use in a shoring system, and each table contains data only for the particular soil type in which the excavation or portion of the excavation is made. The data are arranged to allow the user the flexibility to select from among several acceptable configurations of members based on varying the horizontal spacing of the crossbraces. Stable rock is exempt from shoring requirements and therefore, no data are presented for this condition. (2) Information concerning the basis of the tabular data and the limitations of the data is presented in paragraph (d) of this appendix, and on the tables themselves. (3) Information explaining the use of the tabular data is presented in paragraph (e) of this appendix. (4) Information illustrating the use of the tabular data is presented in paragraph (f) of this appendix. (5) Miscellaneous notations regarding Tables C-1.1 through C-1.3 and Tables C-2.1 through C-2.3 are presented in paragraph (g) of this Appendix. (d) Basis and limitations of the data —(1) Dimensions of timber members. (i) The sizes of the timber members listed in Tables C-1.1 through C-1.3 are taken from the National Bureau of Standards (NBS) report, “Recommended Technical Provisions for Construction Practice in Shoring and Sloping of Trenches and Excavations.” In addition, where NBS did not recommend specific sizes of members, member sizes are based on an analysis of the sizes required for use by existing codes and on empirical practice. (ii) The required dimensions of the members listed in Tables C-1.1 through C-1.3 refer to actual dimensions and not nominal dimensions of the timber. Employers wanting to use nominal size shoring are directed to Tables C-2.1 through C-2.3, or have this choice under § 1926.652(c)(3), and are referred to The Corps of Engineers, The Bureau of Reclamation or data from other acceptable sources. (2) Limitation of application. (i) It is not intended that the timber shoring specification apply to every situation that may be experienced in the field. These data were developed to apply to the situations that are most commonly experienced in current trenching practice. Shoring systems for use in situations that are not covered by the data in this appendix must be designed as specified in § 1926.652(c). (ii) When any of the following conditions are present, the members specified in the tables are not considered adequate. Either an alternate timber shoring system must be designed or another type of protective system designed in accordance with § 1926.652. (A) When loads imposed by structures or by stored material adjacent to the trench weigh in excess of the load imposed by a two-foot soil surcharge. The term “adjacent” as used here means the area within a horizontal distance from the edge of the trench equal to the depth of the trench. (B) When vertical loads imposed on cross braces exceed a 240-pound gravity load distributed on a one-foot section of the center of the crossbrace. (C) When surcharge loads are present from equipment weighing in excess of 20,000 pounds. (D) When only the lower portion of a trench is shored and the remaining portion of the trench is sloped or benched unless: The sloped portion is sloped at an angle less steep than three horizontal to one vertical; or the members are selected from the tables for use at a depth which is determined from the top of the overall trench, and not from the toe of the sloped portion. (e) Use of Tables. 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. (f) Examples to Illustrate the Use of Tables C-1.1 through C-1.3. (1) Example 1. 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. (2) Example 2. 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. (3) Example 3. 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. (4) Example 4. 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. (g) Notes for all Tables. 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.
Appendix D to Subpart P of Part 1926—Aluminum Hydraulic Shoring for Trenches (a) Scope. 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). (b) Soil Classification. 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. (c) Presentation of Information. Information is presented in several forms as follows: (1) Information is presented in tabular form in Tables D-1.1, D-1.2, D-1.3 and E-1.4. Each table presents the maximum vertical and horizontal spacings that may be used with various aluminum member sizes and various hydraulic cylinder sizes. Each table contains data only for the particular soil type in which the excavation or portion of the excavation is made. Tables D-1.1 and D-1.2 are for vertical shores in Types A and B soil. Tables D-1.3 and D1.4 are for horizontal waler systems in Types B and C soil. (2) Information concerning the basis of the tabular data and the limitations of the data is presented in paragraph (d) of this appendix. (3) Information explaining the use of the tabular data is presented in paragraph (e) of this appendix. (4) Information illustrating the use of the tabular data is presented in paragraph (f) of this appendix. (5) Miscellaneous notations (footnotes) regarding Table D-1.1 through D-1.4 are presented in paragraph (g) of this appendix. (6) Figures, illustrating typical installations of hydraulic shoring, are included just prior to the Tables. The illustrations page is entitled “Aluminum Hydraulic Shoring; Typical Installations.” (d) Basis and limitations of the data. (1) Vertical shore rails and horizontal wales are those that meet the Section Modulus requirements in the D-1 Tables. Aluminum material is 6061-T6 or material of equivalent strength and properties. (2) Hydraulic cylinders specifications. (i) 2-inch cylinders shall be a minimum 2-inch inside diameter with a minimum safe working capacity of no less than 18,000 pounds axial compressive load at maximum extension. Maximum extension is to include full range of cylinder extensions as recommended by product manufaturer. (ii) 3-inch cylinders shall be a minimum 3-inch inside diameter with a safe working capacity of not less than 30,000 pounds axial compressive load at extensions as recommended by product manufacturer. (3) Limitation of application. (i) It is not intended that the aluminum hydraulic specification apply to every situation that may be experienced in the field. These data were developed to apply to the situations that are most commonly experienced in current trenching practice. Shoring systems for use in situations that are not covered by the data in this appendix must be otherwise designed as specified in § 1926.652(c). (ii) When any of the following conditions are present, the members specified in the Tables are not considered adequate. In this case, an alternative aluminum hydraulic shoring system or other type of protective system must be designed in accordance with § 1926.652. (A) When vertical loads imposed on cross braces exceed a 100 Pound gravity load distributed on a one foot section of the center of the hydraulic cylinder. (B) When surcharge loads are present from equipment weighing in excess of 20,000 pounds. (C) When only the lower portion or a trench is shored and the remaining portion of the trench is sloped or benched unless: The sloped portion is sloped at an angle less steep than three horizontal to one vertical; or the members are selected from the tables for use at a depth which is determined from the top of the overall trench, and not from the toe of the sloped portion. (e) Use of Tables D-1.1, D-1.2, D-1.3 and D-1.4. 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. (f) Example to Illustrate the Use of the Tables: (1) Example 1: 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.) (2) Example 2: 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.) (3) A trench is dug in Type B soil that does not require sheeting, but does experience some minor raveling of the trench face. The trench is 16 feet deep and 9 feet wide. From Table D-1.2: Find vertical shores and 2 inch diameter cylinder (with special oversleeves as designated by footnote #B2) spaced 5.5 feet o.c. horizontally and 4 feet o.c. vertically, plywood (per footnote (g)(7) to the D-1 Table) should be used behind the shores. (See Figures 2 & 3 for typical installations.) (4) Example 4: 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.) (5) Example 5: 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.) (g) Footnotes, and general notes, for Tables D-1.1, D-1.2, D-1.3, and D-1.4. (1) For applications other than those listed in the tables, refer to § 1926.652(c)(2) for use of manufacturer's tabulated data. For trench depths in excess of 20 feet, refer to § 1926.652(c)(2) and § 1926.652(c)(3). (2) 2 inch diameter cylinders, at this width, shall have structural steel tube (3.5 × 3.5 × 0.1875) oversleeves, or structural oversleeves of manufacturer's specification, extending the full, collapsed length. (3) Hydraulic cylinders capacities. (i) 2 inch cylinders shall be a minimum 2-inch inside diameter with a safe working capacity of not less than 18,000 pounds axial compressive load at maximum extension. Maximum extension is to include full range of cylinder extensions as recommended by product manufacturer. (ii) 3-inch cylinders shall be a minimum 3-inch inside diameter with a safe work capacity of not less than 30,000 pounds axial compressive load at maximum extension. Maximum extension is to include full range of cylinder extensions as recommended by product manufacturer. (4) All spacing indicated is measured center to center. (5) Vertical shoring rails shall have a minimum section modulus of 0.40 inch. (6) When vertical shores are used, there must be a minimum of three shores spaced equally, horizontally, in a group. (7) Plywood shall be 1.125 in. thick softwood or 0.75 inch. thick, 14 ply, arctic white birch (Finland form). Please note that plywood is not intended as a structural member, but only for prevention of local raveling (sloughing of the trench face) between shores. (8) See appendix C for timber specifications. (9) Wales are calculated for simple span conditions. (10) See appendix D, item (d), for basis and limitations of the data.
Appendix E to Subpart P of Part 1926—Alternatives to Timber Shoring
Appendix F to Subpart P of Part 1926—Selection of Protective Systems The following figures are a graphic summary of the requirements contained in subpart P for excavations 20 feet or less in depth. Protective systems for use in excavations more than 20 feet in depth must be designed by a registered professional engineer in accordance with § 1926.652 (b) and (c).
[53 FR 22643, June 16, 1988, as amended at 55 FR 42328, Oct. 18, 1990]
[53 FR 22643, June 16, 1988, as amended at 59 FR 40730, Aug. 9, 1994]
[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]
[55 FR 42328, Oct. 18, 1990]
Appendix A to Subpart Q of Part 1926—References to subpart Q of Part 1926 (This appendix is non-mandatory.) 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.
[66 FR 5265, Jan. 18, 2001, as amended at 75 FR 48134, Aug. 9, 2010]
[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]
Table A—Erection Bridging for Short Span Joists 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.
Table B—Erection Bridging for Long Span Joists 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]
The following provisions supplement the requirements of § 1926.21 regarding the hazards addressed in this subpart.
[66 FR 5265, Jan. 18, 2001, as amended at 73 FR 75589, Dec. 12, 2008; 85 FR 8745, Feb. 18, 2020]
Appendix A to Subpart R of Part 1926—Guidelines for Establishing the Components of a Site-specific Erection Plan: Non-mandatory Guidelines for Complying With § 1926.752( e ) (a) General. 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). (b) Development of a site-specific erection plan. 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. (c) Components of a site-specific erection plan. In developing a site-specific erection plan, a steel erector considers the following elements: (1) The sequence of erection activity, developed in coordination with the controlling contractor, that includes the following: (i) Material deliveries: (ii) Material staging and storage; and (iii) Coordination with other trades and construction activities. (2) A description of the crane and derrick selection and placement procedures, including the following: (i) Site preparation; (ii) Path for overhead loads; and (iii) Critical lifts, including rigging supplies and equipment. (3) A description of steel erection activities and procedures, including the following: (i) Stability considerations requiring temporary bracing and guying; (ii) Erection bridging terminus point; (iii) Anchor rod (anchor bolt) notifications regarding repair, replacement and modifications; (iv) Columns and beams (including joists and purlins); (v) Connections; (vi) Decking; and (vii) Ornamental and miscellaneous iron. (4) A description of the fall protection procedures that will be used to comply with § 1926.760. (5) A description of the procedures that will be used to comply with § 1926.759. (6) A description of the special procedures required for hazardous non-routine tasks. (7) A certification for each employee who has received training for performing steel erection operations as required by § 1926.761. (8) A list of the qualified and competent persons. (9) A description of the procedures that will be utilized in the event of rescue or emergency response. (d) Other plan information. The plan: (1) Includes the identification of the site and project; and (2) Is signed and dated by the qualified person(s) responsible for its preparation and modification.
Appendix B to Subpart R of Part 1926 [Reserved]
Appendix C to Subpart R of Part 1926—Illustrations of Bridging Terminus Points: Non-mandatory Guidelines for Complying With §§ 1926.757( a )(10) and § 1926.757( c )(5)
Appendix D to Subpart R of Part 1926—Illustration of the Use of Control Lines To Demarcate Controlled Decking Zones (CDZs): Non-mandatory Guidelines for Complying With § 1926.760( c )(3) (1) When used to control access to areas where leading edge and initial securement of metal deck and other operations connected with leading edge work are taking place, the controlled decking zone (CDZ) is defined by a control line or by any other means that restricts access. (i) A control line for a CDZ is erected not less than 6 feet (1.8 m) nor more than 90 feet (27.4 m) from the leading edge. (ii) Control lines extend along the entire length of the unprotected or leading edge and are approximately parallel to the unprotected or leading edge. (iii) Control lines are connected on each side to a guardrail system, wall, stanchion or other suitable anchorage. (2) Control lines consist of ropes, wires, tapes, or equivalent materials, and supporting stanchions as follows: (i) Each line is rigged and supported in such a way that its lowest point (including sag) is not less than 39 inches (1.0 m) from the walking/working surface and its highest point is not more than 45 inches (1.3 m) from the walking/working surface. (ii) Each line has a minimum breaking strength of 200 pounds (90.8 kg).
Appendix E to Subpart R of Part 1926—Training: Non-mandatory Guidelines for Complying With § 1926.761 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.
Appendix F to Subpart R of Part 1926—Perimeter Columns: Non-Mandatory Guidelines for Complying With § 1926.756( e ) To Protect the Unprotected Side or Edge of a Walking/Working Surface 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.
Appendix G to Subpart R of Part 1926—§ 1926.502 ( b )-( e ) Fall Protection Systems Criteria and Practices (b) “Guardrail systems.” Guardrail systems and their use shall comply with the following provisions: (1) Top edge height of top rails, or equivalent guardrail system members, shall be 42 inches (1.1 m) plus or minus 3 inches (8 cm) above the walking/working level. When conditions warrant, the height of the top edge may exceed the 45-inch height, provided the guardrail system meets all other criteria of this paragraph (§ 1926.502(b)). Note: When employees are using stilts, the top edge height of the top rail, or equivalent member, shall be increased an amount equal to the height of the stilts. (2) Midrails, screens, mesh, intermediate vertical members, or equivalent intermediate structural members shall be installed between the top edge of the guardrail system and the walking/working surface when there is no wall or parapet wall at least 21 inches (53 cm) high. (i) Midrails, when used, shall be installed at a height midway between the top edge of the guardrail system and the walking/working level. (ii) Screens and mesh, when used, shall extend from the top rail to the walking/working level and along the entire opening between top rail supports. (iii) Intermediate members (such as balusters), when used between posts, shall be not more than 19 inches (48 cm) apart. (iv) Other structural members (such as additional midrails and architectural panels) shall be installed such that there are no openings in the guardrail system that are more than 19 inches (.5 m) wide. (3) Guardrail systems shall be capable of withstanding, without failure, a force of at least 200 pounds (890 N) applied within 2 inches (5.1 cm) of the top edge, in any outward or downward direction, at any point along the top edge. (4) When the 200 pound (890 N) test load specified in paragraph (b)(3) of this section (§ 1926.502) is applied in a downward direction, the top edge of the guardrail shall not deflect to a height less than 39 inches (1.0 m) above the walking/working level. Guardrail system components selected and constructed in accordance with the appendix B to subpart M of this part will be deemed to meet this requirement. (5) Midrails, screens, mesh, intermediate vertical members, solid panels, and equivalent structural members shall be capable of withstanding, without failure, a force of at least 150 pounds (666 N) applied in any downward or outward direction at any point along the midrail or other member. (6) Guardrail systems shall be so surfaced as to prevent injury to an employee from punctures or lacerations, and to prevent snagging of clothing. (7) The ends of all top rails and midrails shall not overhang the terminal posts, except where such overhang does not constitute a projection hazard. (8) Steel banding and plastic banding shall not be used as top rails or midrails. (9) Top rails and midrails shall be at least one-quarter inch (0.6 cm) nominal diameter or thickness to prevent cuts and lacerations. If wire rope is used for top rails, it shall be flagged at not more than 6-foot intervals with high-visibility material. (10) When guardrail systems are used at hoisting areas, a chain, gate or removable guardrail section shall be placed across the access opening between guardrail sections when hoisting operations are not taking place. (11) When guardrail systems are used at holes, they shall be erected on all unprotected sides or edges of the hole. (12) When guardrail systems are used around holes used for the passage of materials, the hole shall have not more than two sides provided with removable guardrail sections to allow the passage of materials. When the hole is not in use, it shall be closed over with a cover, or a guardrail system shall be provided along all unprotected sides or edges. (13) When guardrail systems are used around holes which are used as points of access (such as ladderways), they shall be provided with a gate, or be so offset that a person cannot walk directly into the hole. (14) Guardrail systems used on ramps and runways shall be erected along each unprotected side or edge. (15) Manila, plastic or synthetic rope being used for top rails or midrails shall be inspected as frequently as necessary to ensure that it continues to meet the strength requirements of paragraph (b)(3) of this section (§ 1926.502). (c) Safety net systems. Safety net systems and their use shall comply with the following provisions: (1) Safety nets shall be installed as close as practicable under the walking/working surface on which employees are working, but in no case more than 30 feet (9.1 m) below such level. When nets are used on bridges, the potential fall area from the walking/working surface to the net shall be unobstructed. (2) Safety nets shall extend outward from the outermost projection of the work surface as follows: 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 (3) Safety nets shall be installed with sufficient clearance under them to prevent contact with the surface or structures below when subjected to an impact force equal to the drop test specified in paragraph (4) of this section [§ 1926.502]. (4) Safety nets and their installations shall be capable of absorbing an impact force equal to that produced by the drop test specified in paragraph (c)(4)(i) of this section [§ 1926.502]. (i) Except as provided in paragraph (c)(4)(ii) of this section (§ 1926.502), safety nets and safety net installations shall be drop-tested at the jobsite after initial installation and before being used as a fall protection system, whenever relocated, after major repair, and at 6-month intervals if left in one place. The drop-test shall consist of a 400 pound (180 kg) bag of sand 30 + or −2 inches (76 + or −5 cm) in diameter dropped into the net from the highest walking/working surface at which employees are exposed to fall hazards, but not from less than 42 inches (1.1 m) above that level. (ii) When the employer can demonstrate that it is unreasonable to perform the drop-test required by paragraph (c)(4)(i) of this section (§ 1926.502), the employer (or a designated competent person) shall certify that the net and net installation is in compliance with the provisions of paragraphs (c)(3) and (c)(4)(i) of this section (§ 1926.502) by preparing a certification record prior to the net being used as a fall protection system. The certification record must include an identification of the net and net installation for which the certification record is being prepared; the date that it was determined that the identified net and net installation were in compliance with paragraph (c)(3) of this section (§ 1926.502) and the signature of the person making the determination and certification. The most recent certification record for each net and net installation shall be available at the jobsite for inspection. (5) Defective nets shall not be used. Safety nets shall be inspected at least once a week for wear, damage, and other deterioration. Defective components shall be removed from service. Safety nets shall also be inspected after any occurrence which could affect the integrity of the safety net system. (6) Materials, scrap pieces, equipment, and tools which have fallen into the safety net shall be removed as soon as possible from the net and at least before the next work shift. (7) The maximum size of each safety net mesh opening shall not exceed 36 square inches (230 cm) nor be longer than 6 inches (15 cm) on any side, and the opening, measured center-to-center of mesh ropes or webbing, shall not be longer than 6 inches (15 cm). All mesh crossings shall be secured to prevent enlargement of the mesh opening. (8) Each safety net (or section of it) shall have a border rope for webbing with a minimum breaking strength of 5,000 pounds (22.2 kN). (9) Connections between safety net panels shall be as strong as integral net components and shall be spaced not more than 6 inches (15 cm) apart. (d) “Personal fall arrest systems.” 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 (§ 1926.502). (1) Connectors shall be drop forged, pressed or formed steel, or made of equivalent materials. (2) Connectors shall have a corrosion-resistant finish, and all surfaces and edges shall be smooth to prevent damage to interfacing parts of the system. (3) Dee-rings and snaphooks shall have a minimum tensile strength of 5,000 pounds (22.2 kN). (4) Dee-rings and snaphooks shall be proof-tested to a minimum tensile load of 3,600 pounds (16 kN) without cracking, breaking, or taking permanent deformation. (5) Snaphooks shall be sized to be compatible with the member to which they are connected to prevent unintentional disengagement of the snaphook by depression of the snaphook keeper by the connected member, or shall be a locking type snaphook designed and used to prevent disengagement of the snaphook by the contact of the snaphook keeper by the connected member. Effective January 1, 1998, only locking type snaphooks shall be used. (6) Unless the snaphook is a locking type and designed for the following connections, snaphooks shall not be engaged: (i) directly to webbing, rope or wire rope; (ii) to each other; (iii) to a dee-ring to which another snaphook or other connector is attached; (iv) to a horizontal lifeline; or (v) to any object which is incompatibly shaped or dimensioned in relation to the snaphook such that unintentional disengagement could occur by the connected object being able to depress the snaphook keeper and release itself. (7) On suspended scaffolds or similar work platforms with horizontal lifelines which may become vertical lifelines, the devices used to connect to a horizontal lifeline shall be capable of locking in both directions on the lifeline. (8) Horizontal lifelines shall be designed, installed, and used, under the supervision of a qualified person, as part of a complete personal fall arrest system, which maintains a safety factor of at least two. (9) Lanyards and vertical lifelines shall have a minimum breaking strength of 5,000 pounds (22.2 kN). (10)(i) Except as provided in paragraph (d)(10)(ii) of this section [§ 1926.502], when vertical lifelines are used, each employee shall be attached to a separate lifeline. (ii) During the construction of elevator shafts, two employees may be attached to the same lifeline in the hoistway, provided both employees are working atop a false car that is equipped with guardrails; the strength of the lifeline is 10,000 pounds [5,000 pounds per employee attached] (44.4 kN); and all other criteria specified in this paragraph for lifelines have been met. (11) Lifelines shall be protected against being cut or abraded. (12) Self-retracting lifelines and lanyards which automatically limit free fall distance to 2 feet (0.61 m) or less shall be capable of sustaining a minimum tensile load of 3,000 pounds (13.3 kN) applied to the device with the lifeline or lanyard in the fully extended position. (13) Self-retracting lifelines and lanyards which do not limit free fall distance to 2 feet (0.61 m) or less, ripstitch lanyards, and tearing and deforming lanyards shall be capable of sustaining a minimum tensile load of 5,000 pounds (22.2 kN) applied to the device with the lifeline or lanyard in the fully extended position. (14) Ropes and straps (webbing) used in lanyards, lifelines, and strength components of body belts and body harnesses shall be made from synthetic fibers. (15) Anchorages used for attachment of personal fall arrest equipment shall be independent of any anchorage being used to support or suspend platforms and capable of supporting at least 5,000 pounds (22.2 kN) per employee attached, or shall be designed, installed, and used as follows: (i) as part of a complete personal fall arrest system which maintains a safety factor of at least two; and (ii) under the supervision of a qualified person. (16) Personal fall arrest systems, when stopping a fall, shall: (i) limit maximum arresting force on an employee to 900 pounds (4 kN) when used with a body belt; (ii) limit maximum arresting force on an employee to 1,800 pounds (8 kN) when used with a body harness; (iii) be rigged such that an employee can neither free fall more than 6 feet (1.8 m), nor contact any lower level; (iv) bring an employee to a complete stop and limit maximum deceleration distance an employee travels to 3.5 feet (1.07 m); and, (v) have sufficient strength to withstand twice the potential impact energy of an employee free falling a distance of 6 feet (1.8 m), or the free fall distance permitted by the system, whichever is less. Note: If the personal fall arrest system meets the criteria and protocols contained in appendix C to subpart M, and if the system is being used by an employee having a combined person and tool weight of less than 310 pounds (140 kg), the system will be considered to be in compliance with the provisions of paragraph (d)(16) of this section [§ 1926.502]. If the system is used by an employee having a combined tool and body weight of 310 pounds (140 kg) or more, then the employer must appropriately modify the criteria and protocols of the appendix to provide proper protection for such heavier weights, or the system will not be deemed to be in compliance with the requirements of paragraph (d)(16) of this section (§ 1926.502). (17) The attachment point of the body belt shall be located in the center of the wearer's back. The attachment point of the body harness shall be located in the center of the wearer's back near shoulder level, or above the wearer's head. (18) Body belts, harnesses, and components shall be used only for employee protection (as part of a personal fall arrest system or positioning device system) and not to hoist materials. (19) Personal fall arrest systems and components subjected to impact loading shall be immediately removed from service and shall not be used again for employee protection until inspected and determined by a competent person to be undamaged and suitable for reuse. (20) The employer shall provide for prompt rescue of employees in the event of a fall or shall assure that employees are able to rescue themselves. (21) Personal fall arrest systems shall be inspected prior to each use for wear, damage and other deterioration, and defective components shall be removed from service. (22) Body belts shall be at least one and five-eighths (1 5/8 ) inches (4.1 cm) wide. (23) Personal fall arrest systems shall not be attached to guardrail systems, nor shall they be attached to hoists except as specified in other subparts of this Part. (24) When a personal fall arrest system is used at hoist areas, it shall be rigged to allow the movement of the employee only as far as the edge of the walking/working surface. (e) Positioning device systems. Positioning device systems and their use shall conform to the following provisions: (1) Positioning devices shall be rigged such that an employee cannot free fall more than 2 feet (.9 m). (2) Positioning devices shall be secured to an anchorage capable of supporting at least twice the potential impact load of an employee's fall or 3,000 pounds (13.3 kN), whichever is greater. (3) Connectors shall be drop forged, pressed or formed steel, or made of equivalent materials. (4) Connectors shall have a corrosion-resistant finish, and all surfaces and edges shall be smooth to prevent damage to interfacing parts of this system. (5) Connecting assemblies shall have a minimum tensile strength of 5,000 pounds (22.2 kN) (6) Dee-rings and snaphooks shall be proof-tested to a minimum tensile load of 3,600 pounds (16 kN) without cracking, breaking, or taking permanent deformation. (7) Snaphooks shall be sized to be compatible with the member to which they are connected to prevent unintentional disengagement of the snaphook by depression of the snaphook keeper by the connected member, or shall be a locking type snaphook designed and used to prevent disengagement of the snaphook by the contact of the snaphook keeper by the connected member. As of January 1, 1998, only locking type snaphooks shall be used. (8) Unless the snaphook is a locking type and designed for the following connections, snaphooks shall not be engaged: (i) directly to webbing, rope or wire rope; (ii) to each other; (iii) to a dee-ring to which another snaphook or other connector is attached; (iv) to a horizontal lifeline; or to depress the snaphook keeper and release itself. (v) to any object which is incompatibly shaped or dimensioned in relation to the snaphook such that unintentional disengagement could occur by the connected object being able to depress the snaphook keeper and release itself. (9) Positioning device systems shall be inspected prior to each use for wear, damage, and other deterioration, and defective components shall be removed from service. (10) Body belts, harnesses, and components shall be used only for employee protection (as part of a personal fall arrest system or positioning device system) and not to hoist materials.
Appendix H to Subpart R of Part 1926—Double Connections: Illustration of a Clipped End Connection and a Staggered Connection: Non-Mandatory Guidelines for Complying With § 1926.756( c )(1) 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.
“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]
[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]
Appendix A to Subpart S of Part 1926—Decompression Tables 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; Important Note: The Pressure Reduction in Each Stage is Accomplished at a Uniform Rate. Do Not Interpolate Between Values Shown on the Tables. Use the Next Higher Value of Working Chamber Pressure or Exposure Time Should the Actual Working Chamber Pressure or the Actual Exposure Time, Respectively, Fall Between Those for Which Calculated Values Are Shown in the Body of the Tables. 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 Decompression Table No. 1—Total Decompression Time 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 Decompression Table No. 2 [Do not interpolate, use next higher value for conditions not computed] 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 Decompression Table No. 2—Continued [Do not interpolate, use next higher value for conditions not computed] 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]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 58 FR 35184, 35311, June 30, 1993]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 80 FR 60040, Oct. 5, 2015]
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 80 FR 25518, May 4, 2015]
Table V-1—Flammability Test 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.
Table V-3—Electrical Component of the Minimum Approach Distance (D; in Meters) at 5.1 to 72.5 kV 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
Table V-4—Altitude Correction Factor 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
Table V-5—Alternative Minimum Approach Distances for Voltages of 72.5 kV and Less 1 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.
Table V-6—Alternative Minimum Approach Distances for Voltages of More Than 72.5 kV 1 2 3 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.
Table V-7—DC Live-Line Minimum Approach Distance (in Meters) With Overvoltage Factor 1 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.
Table V-8—Assumed Maximum Per-Unit Transient Overvoltage 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]
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 —(1) Communication 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.
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]
Appendix A to Subpart V of Part 1926 [Reserved]
Appendix B to Subpart V of Part 1926—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 §§ 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. Note to the definition of “guarded”: Wires that are insulated, but not otherwise protected, are not guarded. Insulated. Separated from other conducting surfaces by a dielectric (including air space) offering a high resistance to the passage of current. Note to the definition of “insulated”: When any object is said to be insulated, it is understood to be insulated for the conditions to which it normally is subjected. Otherwise, it is, for the purpose of this subpart, uninsulated. 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. Table 1—Sparkover Distance for Rod-to-Rod Gap 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. Table 2 illustrates how to derive the electrical component of the minimum approach distance for voltages from 5.1 to 72.5 kilovolts, before the application of any altitude correction factor, as explained later. Table 2—Calculating the Electrical Component of MAD—751 V to 72.5 kV 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 = 0.3048( C + a ) V L-G T Where: D = Electrical component of the minimum approach distance in air in meters; C = a correction factor associated with the variation of gap sparkover with voltage; 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 = Maximum transient overvoltage factor in per unit. 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 = 1.35 T L-G + 0.45. 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. Table 4 summarizes the ergonomic component of the minimum approach distance for various voltage ranges. Table 4—Ergonomic Component of Minimum Approach Distance 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. Table 5—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. Note: All rounding must be to the next higher value (that is, always round up). 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. This value equals the withstand voltage of the protective gap. Step 2. Using test data for a particular protective gap, select a gap that has a critical sparkover voltage greater than or equal to: 561 kV ÷ 0.85 = 660 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: 665 kV × 1.10 = 732 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 = 2.29m(7.6ft) 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. Table 6—Minimum Approach Distances 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. Table 7—AC Minimum Approach Distances—72.6 to 121.0 kV 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 Table 8—AC Minimum Approach Distances—121.1 to 145.0 kV 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 Table 9—AC Minimum Approach Distances—145.1 to 169.0 kV 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 Table 10—AC Minimum Approach Distances—169.1 to 242.0 kV 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 Table 11—AC Minimum Approach Distances—242.1 to 362.0 kV 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 Table 12—AC Minimum Approach Distances—362.1 to 420.0 kV 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 Table 13—AC Minimum Approach Distances—420.1 to 550.0 kV 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 Table 14—AC Minimum Approach Distances—550.1 to 800.0 kV 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]
Appendix C to Subpart V of Part 1926—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. Figure 2 illustrates step and touch potentials. III. Protecting Workers From Hazardous Differences in Electrical Potential 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.
Appendix D to Subpart V of Part 1926—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) 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.
Appendix E to Subpart V of Part 1926—Protection From Flames and Electric Arcs 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 Table 1 provides task-based examples of exposure assessments. Table 1—Example Assessments for Various Tasks 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. Table 2—Methods of Calculating Incident Heat Energy From an Electric Arc 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. Table 3—Selecting a Reasonable Incident-Energy Calculation Method 1 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. Table 4—Selecting a Reasonable Distance from the Employee to the Electric Arc 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. Table 5—Selecting a Reasonable Arc Gap 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. Table 7 presents similar estimates for employees using live-line tools to perform work on overhead systems operating at voltages of 4 to 800 kilovolts. The table assumes that the arc length will be equal to the sparkover distance 4 and that the employee will be a distance from the arc equal to the minimum approach distance minus twice the sparkover distance. 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. Table 6—Incident Heat Energy for Various Fault Currents, Clearing Times, and Voltages of 4.0 to 46.0 kV: Rubber Insulating Glove Exposures Involving Phase-to-Ground Arcs in Open Air Only * † ‡ 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. Table 7—Incident Heat Energy for Various Fault Currents, Clearing Times, and Voltages: Live-Line Tool Exposures Involving Phase-to-Ground Arcs in Open Air Only * † ‡ # 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.
Appendix F to Subpart V of Part 1926—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); Note: Gauges are available to assist in determining whether gaffs are long enough and shaped to easily penetrate poles or trees. 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 Subpart V of Part 1926—Reference Documents 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. ANSI/SIA A92.2-2009, American National Standard for Vehicle-Mounted Elevating and Rotating Aerial Devices. ANSI Z133-2012, American National Standard Safety Requirements for Arboricultural Operations—Pruning, Trimming, Repairing, Maintaining, and Removing Trees, and Cutting Brush. ANSI/IEEE Std 935-1989, IEEE Guide on Terminology for Tools and Equipment to Be Used in Live Line Working. ASME B20.1-2012, Safety Standard for Conveyors and Related Equipment. ASTM D120-09, Standard Specification for Rubber Insulating Gloves. ASTM D149-09 (2013), Standard Test Method for Dielectric Breakdown Voltage and Dielectric Strength of Solid Electrical Insulating Materials at Commercial Power Frequencies. ASTM D178-01 (2010), Standard Specification for Rubber Insulating Matting. ASTM D1048-12, Standard Specification for Rubber Insulating Blankets. ASTM D1049-98 (2010), Standard Specification for Rubber Insulating Covers. ASTM D1050-05 (2011), Standard Specification for Rubber Insulating Line Hose. ASTM D1051-08, Standard Specification for Rubber Insulating Sleeves. ASTM F478-09, Standard Specification for In-Service Care of Insulating Line Hose and Covers. ASTM F479-06 (2011), Standard Specification for In-Service Care of Insulating Blankets. ASTM F496-08, Standard Specification for In-Service Care of Insulating Gloves and Sleeves. ASTM F711-02 (2007), Standard Specification for Fiberglass-Reinforced Plastic (FRP) Rod and Tube Used in Live Line Tools. ASTM F712-06 (2011), Standard Test Methods and Specifications for Electrically Insulating Plastic Guard Equipment for Protection of Workers. ASTM F819-10, Standard Terminology Relating to Electrical Protective Equipment for Workers. ASTM F855-09, Standard Specifications for Temporary Protective Grounds to Be Used on De-energized Electric Power Lines and Equipment. ASTM F887-12 e1 , Standard Specifications for Personal Climbing Equipment. ASTM F914/F914M-10, Standard Test Method for Acoustic Emission for Aerial Personnel Devices Without Supplemental Load Handling Attachments. ASTM F1116-03 (2008), Standard Test Method for Determining Dielectric Strength of Dielectric Footwear. ASTM F1117-03 (2008), Standard Specification for Dielectric Footwear. ASTM F1236-96 (2012), Standard Guide for Visual Inspection of Electrical Protective Rubber Products. ASTM F1430/F1430M-10, Standard Test Method for Acoustic Emission Testing of Insulated and Non-Insulated Aerial Personnel Devices with Supplemental Load Handling Attachments. ASTM F1505-10, Standard Specification for Insulated and Insulating Hand Tools. ASTM F1506-10a, 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. ASTM F1564-13, Standard Specification for Structure-Mounted Insulating Work Platforms for Electrical Workers. ASTM F1701-12, Standard Specification for Unused Polypropylene Rope with Special Electrical Properties. ASTM F1742-03 (2011), Standard Specification for PVC Insulating Sheeting. ASTM F1796-09, Standard Specification for High Voltage Detectors—Part 1 Capacitive Type to be Used for Voltages Exceeding 600 Volts AC. ASTM F1797-09 ε 1 , Standard Test Method for Acoustic Emission Testing of Insulated and Non-Insulated Digger Derricks. ASTM F1825-03 (2007), Standard Specification for Clampstick Type Live Line Tools. ASTM F1826-00 (2011), Standard Specification for Live Line and Measuring Telescoping Tools. ASTM F1891-12, Standard Specification for Arc and Flame Resistant Rainwear. ASTM F1958/F1958M-12, Standard Test Method for Determining the Ignitability of Non-flame-Resistant Materials for Clothing by Electric Arc Exposure Method Using Mannequins. ASTM F1959/F1959M-12, Standard Test Method for Determining the Arc Rating of Materials for Clothing. IEEE Stds 4-1995, 4a-2001 (Amendment to IEEE Standard Techniques for High-Voltage Testing ), IEEE Standard Techniques for High-Voltage Testing. IEEE Std 62-1995, IEEE Guide for Diagnostic Field Testing of Electric Power Apparatus—Part 1: Oil Filled Power Transformers, Regulators, and Reactors. IEEE Std 80-2000, Guide for Safety in AC Substation Grounding. IEEE Std 100-2000, The Authoritative Dictionary of IEEE Standards Terms Seventh Edition. IEEE Std 516-2009, IEEE Guide for Maintenance Methods on Energized Power Lines. IEEE Std 524-2003, IEEE Guide to the Installation of Overhead Transmission Line Conductors. IEEE Std 957-2005, IEEE Guide for Cleaning Insulators. IEEE Std 1048-2003, IEEE Guide for Protective Grounding of Power Lines. IEEE Std 1067-2005, 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 Std 1307-2004, IEEE Standard for Fall Protection for Utility Work. IEEE Stds 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), IEEE Guide for Performing Arc-Flash Hazard Calculations. IEEE C2-2012, National Electrical Safety Code. NFPA 70E-2012, Standard for Electrical Safety in the Workplace.
[44 FR 8577, Feb. 9, 1979; 44 FR 20940, Apr. 6, 1979, as amended at 84 FR 21577, May 14, 2019]
[84 FR 21578, May 14, 2019]
[70 FR 76985, Dec. 29, 2005, as amended at 71 FR 41129, July 20, 2006; 84 FR 21578, May 14, 2019]
[84 FR 21578, May 14, 2019]
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]
[55 FR 47687, Nov. 14, 1990; 56 FR 2585, Jan. 23, 1991; 56 FR 5061, Feb. 7, 1991; 56 FR 41794, Aug. 23, 1991]
[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.
Appendix A to Subpart X of Part 1926—Ladders 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]
Appendix A to Subpart Y of Part 1926—Examples of Conditions Which May Restrict or Limit Exposure to Hyperbaric Conditions Note: The requirements applicable to construction work under this appendix A are identical to those set forth at appendix A to Subpart T of part 1910 of this chapter. [61 FR 31432, June 20, 1996]
Appendix B to Subpart Y of Part 1926—Guidelines for Scientific Diving Note: The requirements applicable to construction work under this appendix B are identical to those set forth at appendix B to subpart T of part 1910 of this chapter. [61 FR 31433, June 20, 1996]
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.
[51 FR 22756, June 20, 1986]
Editorial Note: For Federal Register citations affecting § 1926.1101, see the List of CFR Sections Affected, which appears in the Finding Aids section of the printed volume and at www.govinfo.gov.
[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]
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.
[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]
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.
[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]
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)-(12) of this section or, if multiple physician review under paragraph (l)(13) of this section or the alternative physician determination under paragraph (l)(14) of this section is invoked, it is the final, written medical finding, recommendation or determination that emerges from that process.
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.
[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]
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.
Table 1—Specified Exposure Control Methods When Working With Materials Containing Crystalline Silica 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.
[81 FR 16876, Mar. 25, 2016]
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.
[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:
Dismantling (including dismantling for changing the length of) booms and jibs.
The additional measures are:
Table A—Minimum Clearance Distances 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]
Table T—Minimum Clearance Distances While Traveling With No Load 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).
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.
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.
Hand signal charts must be either posted on the equipment or conspicuously posted in the vicinity of the hoisting operations.
[83 FR 56244, Nov. 9, 2018]
The employer must provide training as follows:
[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.
[75 FR 48135, Aug. 9, 2010, as amended at 85 FR 8746, Feb. 18, 2020]
The following requirements apply to equipment that has a manufacturer-rated hoisting/lifting capacity of more than 2,000 pounds.
Table M1 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
Table M2 Operated at Wind speed (mph) Minimum freeboard (ft) Rated capacity 60 2 Rated capacity plus 25% 60 1 High boom, no load 60 2
Table M3 Operated at Wind speed For backward stability of the boom: High boom, no load, full back list (least stable condition) 90 mph.
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.
[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]
Appendix A to Subpart CC of Part 1926—Standard Hand Signals
Appendix B to Subpart CC of Part 1926—Assembly/Disassembly: Sample Procedures for Minimizing the Risk of Unintended Dangerous Boom Movement 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.
Appendix C to Subpart CC of Part 1926—Operator Certification: Written Examination: Technical Knowledge Criteria 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. (a) General technical information. (1) The functions and limitations of the crane and attachments. (2) Wire rope: (i) Background information necessary to understand the inspection and removal from service criteria in § 1926.1413 and § 1926.1414. (ii) Capacity and when multi-part rope is needed. (iii) Relationship between line pull and safe working load. (iv) How to determine the manufacturer's recommended rope for the crane. (3) Rigging devices and their use, such as: (i) Slings. (ii) Spreaders. (iii) Lifting beams. (iv) Wire rope fittings, such as clips, shackles and wedge sockets. (v) Saddles (softeners). (vi) Clamps (beams). (4) The technical limitations of protective measures against electrical hazards: (i) Grounding. (ii) Proximity warning devices. (iii) Insulated links. (iv) Boom cages. (v) Proximity to electric power lines, radii, and microwave structures. (5) The effects of load share and load transfer in multi-crane lifts. (6) Basic crane terms. (7) The basics of machine power flow systems. (i) Mechanical. (ii) Electrical. (iii) Pneumatic. (iv) Hydraulic. (v) Combination. (8) The significance of the instruments and gauge readings. (9) The effects of thermal expansion and contraction in hydraulic cylinders. (10) Background information necessary to understand the requirements of pre-operation and inspection. (11) How to use the safety devices and operational aids required under § 1926.1415 and § 1926.1416. (12) The difference between duty-cycle and lifting operations. (13) How to calculate net capacity for every possible configuration of the equipment using the manufacturer's load chart. (14) How to use manufacturer-approved attachments and their effect on the equipment. (15) How to obtain dimensions, weight, and center of gravity of the load. (16) The effects of dynamic loading from: (i) Wind. (ii) Stopping and starting. (iii) Impact loading. (iv) Moving with the load. (17) The effect of side loading. (18) The principles of backward stability. (b) Site information. (1) How to identify the suitability of the supporting ground/surface to support the expected loads of the operation. Elements include: (i) Weaknesses below the surface (such as voids, tanks, loose fill). (ii) Weaknesses on the surface (such as retaining walls, slopes, excavations, depressions). (2) Proper use of mats, blocking/cribbing, outriggers, stabilizers, or crawlers. (3) Identification of site hazards such as power lines, piping, and traffic. (4) How to review operation plans with supervisors and other workers (such as the signal person), including how to determine working height, boom length, load radius, and travel clearance. (5) How to determine if there is adequate room for extension of crawlers or outriggers/stabilizers and counterweights. (c) Operations. (1) How to pick, carry, swing and place the load smoothly and safely on rubber tires and on outriggers/stabilizers or crawlers (where applicable). (2) How to communicate at the site with supervisors, the crew and the signal person. (3) Proper procedures and methods of reeving wire ropes and methods of reeving multiple-part lines and selecting the proper load block and/or ball. (4) How to react to changes in conditions that affect the safe operation of the equipment. (5) How to shut down and secure the equipment properly when leaving it unattended. (6) Know how to apply the manufacturer's specifications for operating in various weather conditions, and understand how environmental conditions affect the safe operation of the equipment. (7) How to properly level the equipment. (8) How to verify the weight of the load and rigging prior to initiating the lift. (9) How to determine where the load is to be picked up and placed and how to verify the radii. (10) Know basic rigging procedures. (11) How to carry out the shift inspection required in this subpart. (12) Know that the following operations require specific procedures and skill levels: (i) Multi-crane lifts. (ii) Hoisting personnel. (iii) Clamshell/dragline operations. (iv) Pile driving and extracting. (v) Concrete operations, including poured-in-place and tilt-up. (vi) Demolition operations. (vii) Operations on water. (viii) Magnet operations. (ix) Multi-drum operations. (13) Know the proper procedures for operating safely under the following conditions: (i) Traveling with suspended loads. (ii) Approaching a two-block condition. (iii) Operating near power lines. (iv) Hoisting personnel. (v) Using other than full outrigger/crawler or stabilizer extensions. (vi) Lifting loads from beneath the surface of the water. (vii) Using various approved counterweight configurations. (viii) Handling loads out of the operator's vision (“operating in the blind”). (ix) Using electronic communication systems for signal communication. (14) Know the proper procedures for load control and the use of hand-held tag lines. (15) Know the emergency response procedure for: (i) Fires. (ii) Power line contact. (iii) Loss of stability. (iv) Control malfunction. (v) Two-blocking. (vi) Overload. (vii) Carrier or travel malfunction. (16) Know how to properly use outriggers and stabilizers in accordance with manufacturer specifications. (d) Use of load charts. (1) Know the terminology necessary to use load charts. (2) Know how to ensure that the load chart is the appropriate chart for the equipment in its particular configuration and application. (3) Know how to use load charts. This includes knowing: (i) The operational limitations of load charts and footnotes. (ii) How to relate the chart to the configuration of the crane, crawlers, or outriggers/stabilizers extended or retracted, jib erected or offset, and various counterweight configurations. (iii) The difference between structural capacity and capacity limited by stability. (iv) What is included in capacity ratings. (v) The range diagram and its relationship to the load chart. (vi) The work area chart and its relationship to the load chart. (vii) Where to find and how to use the “parts-of-line” information. (4) Know how to use the load chart together with the load indicators and/or load moment devices.
Appendix A to Part 1926—Designations for General Industry Standards Incorporated Into Body of Construction Standards New Designations for General Industry Standards Incorporated Into Body of Construction Standards 1926 Designations for Applicable 1910 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]