SafetyQuestion 323 of 360
A crew chooses to slope the walls of a trench instead of shoring it. The soil has been classified as Type C (the least stable, such as loose sand or wet soil). What is the maximum allowable slope for Type C soil?
a.Vertical (90 degrees) with no benching
b.1.5 horizontal to 1 vertical (about 34 degrees)
c.0.5 horizontal to 1 vertical (about 63 degrees)
d.3 horizontal to 1 vertical (about 18 degrees)
Explanation
Under Title 8 §1541.1 appendices, Type C soil (the least stable) must be sloped no steeper than 1.5:1, meaning 1.5 feet of horizontal run for each foot of depth, roughly a 34-degree angle. Stronger Type A and B soils allow steeper slopes. When soil type is unknown, it must be treated as Type C to be safe.
Law Reference: Cal/OSHA Title 8 §1541.1Practice all 360 questions free — no signup required.
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