SafetyPregunta 93 de 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
Explicación
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.
Referencia Legal: 29 CFR 1926.652Practica las 110 preguntas gratis — sin registro.
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