Codes & Safety第 119 / 120 题
A plumber is brazing copper joints in a finished mechanical room with combustible wood framing a few feet away. Which practice meets the fire prevention requirements for the work?
a.The acetylene regulator may be set to 20 psig to speed up the braze as long as the cylinder is chained upright
b.A fire extinguisher is kept at the work area and a fire watch is maintained for at least 30 minutes after the torch is shut off
c.A fire watch is required only for welding, since brazing and soldering do not produce enough heat to start a fire
d.Cylinders may be laid on their side while in use provided they are blocked so they cannot roll
解析
Hot work requires suitable fire extinguishing equipment kept ready at the site and a fire watch maintained for at least 30 minutes after the work stops, because smoldering combustibles behind a wall or above a ceiling can take that long to flare up. Acetylene is unstable at pressure and must never be used above 15 psig at the torch. Brazing and soldering both use an open flame and easily ignite framing, insulation and dust, so the fire watch applies to them as well. Cylinders are stored, transported and used upright and secured so the valve cannot be broken off and the acetone in an acetylene cylinder is not drawn into the hose.
法律依据: 29 CFR 1926.352免费刷完整 120 道题库 — 无需注册。
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