Trenching and excavation are widely recognized as among the most hazardous construction operations, resulting in an average of two deaths per month and hundreds of injuries each year due to trench collapses. OSHA has addressed construction-related trenching and excavation hazards by developing specific safety standards for the construction industry, making the requirements easier to understand and providing construction employers with various options for classifying soil and selecting employee protection methods.
Cave-ins pose the greatest risk in trenching and excavation operations, and are much more likely than other excavation-related accidents to result in worker fatalities. One cubic yard of soil can weigh as much as a car. Other potential trenching and excavation hazards include falls, falling loads, hazardous atmospheres, and incidents involving mobile equipment.
There a many factors in determining the proper protective systems to reduce or eliminate trenching and excavation hazards, including soil classification, depth of cut, water content of soil, changes due to weather or climate, surcharge loads (e.g., other materials to be used in the trench) and other operations in the vicinity.
For more information on trenching and excavation safety, including OSHA standards, common hazards and solutions, visit OSHA’s Trenching and Excavation webpage.
The OSHA Training Center is offering OSHA 3015 – Excavation, Trenching, and Soil Mechanics in Dublin, California, on October 2-4. Students will learn about practical soil mechanics and the relationship to the stability of shored and unshored slopes and walls of excavations. Various types of shoring, including hydraulic and wood timbers, are covered. Testing methods are demonstrated and a field exercise is conducted, allowing students to use instruments such as penetrometers, torvane shears and engineering rods.