Codes & SafetyQuestion 114 of 120
A crew is setting sewer pipe in a trench 5 ft 6 in deep with vertical walls cut in previously disturbed soil. No sloping, shoring or shielding has been installed. What does OSHA require before a worker enters?
a.Nothing, because a protective system is required only at 6 ft and greater
b.A warning line at the top of the trench and a spotter watching the walls are sufficient at this depth
c.A protective system such as sloping, benching, shoring or a trench shield must be in place, because the excavation is 5 ft or more in depth
d.The competent person may waive protection if the trench will be open for less than one work shift
Explanation
Employees in an excavation 5 ft deep or more must be protected by an adequate protective system, and the only exception is an excavation made entirely in stable rock. The 6 ft figure is a fall-protection threshold, not the trenching trigger. A warning line and a spotter do nothing to stop a wall from collapsing on someone standing in the trench. The competent person can require protection at less than 5 ft when there are signs of a cave-in hazard, but has no authority to waive it based on how long the trench will stay open.
Law Reference: 29 CFR 1926.652(a)(1)Practice all 120 questions free — no signup required.
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