SafetyQuestion 327 of 360
A worker asks why a 5-foot trench needs protection when the walls 'look solid.' What fact best explains the danger of an unsupported trench wall?
a.Soil is very light, so a collapse is easy to climb out of
b.A cubic yard of soil can weigh over 2,000 to 3,000 pounds, enough to crush or suffocate a buried worker
c.Cave-ins only happen in trenches deeper than 15 feet
d.Soil never collapses if it has not rained recently
Explanation
Soil is deceptively heavy; a single cubic yard can weigh as much as a small car (over 2,000 to 3,000 pounds). A worker buried even to the waist cannot self-rescue and can suffer crushing injuries or asphyxiation before help arrives. That weight is why §1541.1 protective systems exist, and why walls that 'look solid' are still deadly.
Law Reference: Cal/OSHA Title 8 §1541.1Practice all 360 questions free — no signup required.
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