Trenches 5 feet or deeper require a protective system to prevent cave-ins, unless the excavation is in stable rock. Protective measures include sloping, benching, shoring, or shielding. [1]
Trenches more than 20 feet in depth must be designed by a registered professional engineer. [2]
A registered professional engineer must design protective systems for all excavations that are more than 20 feet deep. [3]
Excavations and trenches less than five feet deep must still be sloped, benched, or otherwise supported when a Competent Person determines there is indication of cave-in. [3]
Workers in trenches 4 feet or deeper require a ladder or other safe means of entry and exit located within 25 feet of the worker. [2]
Spoil piles must be kept at least 2 feet away from the trench edge. [2]
A competent person must inspect each trench worksite, including the soil protective system, prior to the start of work, and again if there is a hazard-increasing change in conditions such as a rainstorm. [2]
Important Safety Note:
Always verify safety information with your organization's specific guidelines and local regulations.