According to OSHA 1910.95, what is the permissible exposure limit for noise for eight hours?

• A. 90 dB for eight hours
• B. 95 dB for eight hours
• C. 85 dB for eight hours
• D. 100 dB for eight hours

Answer: (A)

OSHA 1910.95 sets the permissible exposure limit for workplace noise at 90 dBA as an eight-hour time-weighted average. This is the threshold you can be exposed to for a full 8-hour shift without exceeding the limit. The standard uses a 5 dB exchange rate, so each 5 dB increase above 90 dBA cuts the allowable exposure time roughly in half (for example, 95 dBA ≈ 4 hours, 100 dBA ≈ 2 hours, 105 dBA ≈ 1 hour). Exposures at higher levels for eight hours would exceed the PEL unless mitigated by controls or hearing protection. The value 85 dBA is the action level, not the PEL itself.