SafetyQuestion 666 of 700
Workers will enter a 7-foot-deep excavation next to a former solvent storage area where a hazardous atmosphere could exist. Under Cal/OSHA, what is required before and during entry?
a.Nothing special, because open excavations always have fresh air
b.Test only once at the start of the shift and assume conditions stay safe
c.Test the atmosphere for oxygen level and hazardous gases before entry and as often as needed, and provide controls such as ventilation where a hazard could exist
d.Rely on workers noticing symptoms and leaving on their own
Explanation
Correct: where a hazardous atmosphere could reasonably exist in an excavation deeper than 4 ft (near contamination, fuels, or where oxygen may be deficient), the atmosphere must be tested before entry and regularly thereafter, with controls like ventilation and emergency provisions. Assuming fresh air, testing only once, or waiting for symptoms all fail to protect against odorless, invisible hazards.
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