Which noise level corresponds to a daily exposure of 0.25 hours?

Which noise level corresponds to a daily exposure of 0.25 hours?

• A. 115 dB
• B. 110 dB
• C. 100 dB
• D. 102 dB

Answer: (A)

The idea tested is how allowed exposure time changes as noise level increases, using the 5 dB exchange rate. Under the common OSHA framework, 90 dB can be faced for 8 hours. Each 5 dB jump halves the permissible time: 95 dB for 4 hours, 100 dB for 2 hours, 105 dB for 1 hour, 110 dB for 30 minutes, and 115 dB for 15 minutes. A daily exposure of 0.25 hours is 15 minutes, which matches the 115 dB level. The other options would permit longer exposure times (for example, 110 dB allows 30 minutes, 100 dB allows 2 hours, etc.), so they do not correspond to the 15-minute daily exposure.

The idea tested is how allowed exposure time changes as noise level increases, using the 5 dB exchange rate. Under the common OSHA framework, 90 dB can be faced for 8 hours. Each 5 dB jump halves the permissible time: 95 dB for 4 hours, 100 dB for 2 hours, 105 dB for 1 hour, 110 dB for 30 minutes, and 115 dB for 15 minutes.

A daily exposure of 0.25 hours is 15 minutes, which matches the 115 dB level. The other options would permit longer exposure times (for example, 110 dB allows 30 minutes, 100 dB allows 2 hours, etc.), so they do not correspond to the 15-minute daily exposure.