SafetyQuestion 95 of 110
A plumber must enter a sanitary sewer manhole to make a connection. This is a permit-required confined space. What atmospheric hazard is the leading concern, and what is required before entry?
a.Excess oxygen only, no testing needed
b.High humidity; wear a raincoat
c.Toxic/flammable gases (hydrogen sulfide, methane) and oxygen deficiency; test the atmosphere and ventilate before and during entry
d.Noise; wear earplugs
Explanation
A sewer is a permit-required confined space where hydrogen sulfide, methane, and oxygen deficiency can be immediately dangerous, so the atmosphere must be tested for oxygen, flammables, and toxics and the space ventilated before and continuously during entry. An attendant, retrieval equipment, and a permit are required. Oxygen must be between 19.5 and 23.5 percent.
Law Reference: 29 CFR 1910.146Practice all 110 questions free — no signup required.
Related questions on this topic
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