Which noise level allows a daily exposure of one hour?

Which noise level allows a daily exposure of one hour?

• A. 105 dB
• B. 110 dB
• C. 95 dB
• D. 100 dB

Answer: (A)

The key idea is how exposure time changes with noise level using the 5 dB exchange rate. Under OSHA’s PEL, 90 dB allows 8 hours of exposure per day; for every 5 dB increase, the allowable time is halved. So: - 95 dB = 4 hours - 100 dB = 2 hours - 105 dB = 1 hour - 110 dB = 0.5 hours (30 minutes) Therefore, 105 dB is the level that allows about one hour of daily exposure. The other options would yield different exposure times (e.g., 110 dB would be 30 minutes, 95 dB would be 4 hours, etc.).

The key idea is how exposure time changes with noise level using the 5 dB exchange rate. Under OSHA’s PEL, 90 dB allows 8 hours of exposure per day; for every 5 dB increase, the allowable time is halved. So:

• 95 dB = 4 hours

• 100 dB = 2 hours

• 105 dB = 1 hour

• 110 dB = 0.5 hours (30 minutes)

Therefore, 105 dB is the level that allows about one hour of daily exposure. The other options would yield different exposure times (e.g., 110 dB would be 30 minutes, 95 dB would be 4 hours, etc.).