SafetyQuestion 459 of 521
A normal, safe breathable oxygen concentration in a confined space is approximately:
a.19.5% to 23.5%
b.10% to 15%
c.25% to 30%
d.About 5%
Explanation
The acceptable oxygen range for entry is about 19.5% (minimum) to 23.5% (maximum); below 19.5% is oxygen-deficient and above 23.5% is oxygen-enriched and a fire hazard. 10-15% and 5% are dangerously deficient, and 25-30% is enriched and increases combustion risk.
Law Reference: Cal/OSHA Title 8 §5157Practice all 521 questions free — no signup required.
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