Safety第 93 / 110 题
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
解析
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.
法律依据: 29 CFR 1926.652免费刷完整 110 道题库 — 无需注册。
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