What is the general OSHA depth trigger for trench protective systems?
Correct Answer
A) 5 ft or deeper unless an exception applies
OSHA generally requires cave-in protection at 5 ft or deeper unless the excavation is entirely in stable rock; shallower excavations may also need protection if hazards exist.
Why This Is the Correct Answer
OSHA generally requires cave-in protection at 5 ft or deeper unless the excavation is entirely in stable rock; shallower excavations may also need protection if hazards exist.
Why the Other Options Are Wrong
Option B: Set the trench protective system trigger threshold at 2 ft
The trap in B is 2 ft. That selection is wrong because 2 ft uses the wrong excavation protective-system trigger or exception.
Option C: Set the trench protective system trigger threshold at 8 ft
Choice C gives 8 ft. Its specific error: 8 ft uses the wrong excavation protective-system trigger or exception.
Option D: Base the trench protective system trigger response on 20 ft
Choice D (20 ft only) is rejected because 20 ft only uses the wrong excavation protective-system trigger or exception.
Memory Technique
Link trench protective system trigger to its book condition; a different condition means a different answer than 5 ft or deeper unless an exception applies.
Reference Hint
Open 29 CFR Part 1926 (OSHA Construction Standards), 1926-2023 / PSI OSHA Excerpts 2025; use 29 CFR 1926 Subpart P - §1926.652; related §1926.651(d), §1926.651(i), §1926.651(l) to confirm that OSHA generally requires cave-in protection at 5 ft or deeper unless the excavation is entirely in stable rock; shallower excavations may also need protection if hazards exist.
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