How to prevent cave-ins while digging
The accident: A 29-year-old landscape worker and four other laborers are hand digging a 2-foot wide by 16-foot long trench on a private residence to investigate water infiltration. The landscape worker kneels down to inspect a broken drainpipe at the bottom of the east end of the trench, about 10 feet deep. One of the other workers notices a crack in the soil and yells to him. The wall collapses, and the worker is completely covered with soil in seconds. The other laborers begin frantically hand digging to reach the worker. The owner sees the site and calls 911. Firemen and police officers arrive on the scene and continue digging. After 45 minutes, the worker is discovered. He is pronounced dead on the scene from compression/asphyxiation.
The bottom line: Excavation crews are exposed to many hazards, but the main one is the danger of cave-ins. With a higher probability of being fatal compared to other excavation accidents, cave-ins can be prevented if everyone on the site receives the proper training. Here are safe practices to follow when digging on the jobsite:
• Ensure employees who are working in excavations are protected from cave-ins: Use protection systems such as shoring, sloping or excavation boxes. Slope the sides to an angle not steeper than 1 1/2:1 (horizontal to vertical).
• Have a qualified person inspect the excavation, adjacent areas and support systems on an ongoing basis.
• Before digging, call 811 to have a locator mark underground lines, pipes and cables.
• Train employees to recognize and avoid unsafe conditions.
• Develop a trench emergency action plan that describes rescue and medical duties and make sure all of the employees understand these procedures.
• Do not operate equipment near the trench while employees are in it to prevent vibrating the excavation.