SafetyQuestion 328 of 360
A plumber must enter a municipal sewer manhole to clear a blockage. Under Cal/OSHA §5157, why is this classified as a permit-required confined space?
a.Only because it is dark inside
b.Because it requires a locksmith to open
c.It has limited entry/exit and can contain a hazardous atmosphere such as toxic or oxygen-deficient gas
d.Because it is owned by the city rather than a private party
Explanation
Under Title 8 §5157, a permit-required confined space is large enough to enter, has limited means of entry or exit, is not designed for continuous occupancy, and contains a recognized serious hazard such as a hazardous atmosphere or engulfment risk. Sewers and manholes commonly hold hydrogen sulfide, methane, and low oxygen, making them permit-required. A written permit, testing, and an attendant are required before entry.
Law Reference: Cal/OSHA Title 8 §5157Practice all 360 questions free — no signup required.
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