SafetyQuestion 93 of 110
A trench is dug in Type C soil, which OSHA requires to be sloped at 1.5 to 1 (horizontal to vertical). For a trench 8 ft deep, how wide must the sloped opening be beyond the trench bottom on each side?
a.12 ft each side
b.8 ft each side
c.4 ft each side
d.16 ft each side
Explanation
At 1.5 to 1, horizontal run = 1.5 x depth = 1.5 x 8 = 12 ft of slope on each side beyond the trench bottom. Type C is the least stable soil and requires the widest, flattest slope. Type A allows 0.75 to 1 and Type B 1 to 1, so knowing the soil class sets the excavation width.
Law Reference: 29 CFR 1926.652Practice all 110 questions free — no signup required.
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