Safety News
Trenching and Excavation The primary hazard of trenching and excavation work is employee injury from a cave-in. • Before workers enter a trench, a soil analysis should generally be conducted to determine the appropriate employee protection methods such as sloping, benching, shoring or shielding. • Employers should also consider potential struckby hazards associated with heavy equipment, falling loads, and public vehicular traffic in close proximity to the excavation operations. • Also consider potential hazards from undermining sidewalks and buildings. • Other unsafe conditions that may be encountered include hazardous atmospheres and electrical hazards from overhead and underground power lines. • These key trench safety tips will help keep workers safe: • Ensure that there’s a safe way to enter and exit What are the hazards? To prevent injuries during normal entry and exit of a trench or excavation at a job site, employers must provide ladders, stairways, ramps, or other safe means of egress. In some circumstances, when conditions in a trench or excavation become hazardous, survival may depend on how quickly workers can climb out.
• Position the means of egress within 25 lateral feet of workers. • Ensure means of entering and exiting the trench is within the protective system. • Structural ramps that are used for access or egress from excavations must be designed by a competent person. • When two or more components form a ramp or runway, they must be connected to prevent displacement, and be of uniform thickness. • Cleats or other means of connecting runway components must be attached in a way that would not cause tripping (e.g., attached to the bottom of the structure). • Structural ramps used in place of steps must have a non-slip surface. • Use earthen ramps as a means of egress only if a worker can walk them in an upright position, and only if they have been evaluated by a competent person. More Information: • 29 CFR 1926 Subpart P, Excavations. OSHA Standard. • 1926.651 Specific excavation requirements • 1926.651(c) Access and Egress
To manage the hazards: • Provide stairways, ladders, ramps, or other safe means of egress in all trenches that are 4 feet deep or more. 10 Texas Water Utilities Journal | www.twua.org
November 2021
