SafetyQuestion 336 of 360
Cal/OSHA sets a Permissible Exposure Limit (PEL) for hydrogen sulfide, a gas plumbers meet in sewers. Approximately what is the 8-hour PEL for H2S under Title 8?
a.500 ppm
b.100 ppm
c.10 ppm
d.There is no limit for H2S
Explanation
Under Title 8 §5155 (airborne contaminants), the 8-hour permissible exposure limit for hydrogen sulfide is about 10 ppm, with a short-term ceiling that is higher. These limits are low because H2S is acutely toxic; concentrations of a few hundred ppm can cause rapid collapse. Plumbers working around sewage should monitor with a meter and never rely on odor alone.
Law Reference: Cal/OSHA Title 8 §5155Practice all 360 questions free — no signup required.
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