Safety第 92 / 110 题
An excavation for a sewer lateral is dug to a depth of 6 ft in Type C soil. At what depth does OSHA require protective systems (sloping, shoring, or a trench box) for workers entering the trench?
a.Any depth over 2 ft
b.Any depth over 3 ft
c.Only over 10 ft
d.5 ft or more (and any depth if a competent person sees a hazard)
解析
OSHA requires cave-in protection for any trench 5 ft or deeper, and at any depth if a competent person identifies a hazard, so a 6 ft trench must be sloped, shored, or shielded. Trenches less than 5 ft may be exempt only if a competent person finds no cave-in potential. Soil type sets the required slope angle.
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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