Safety第 95 / 110 题
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
解析
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.
法律依据: 29 CFR 1910.146免费刷完整 110 道题库 — 无需注册。
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