INFORMATION REQUIRED BY E.P.A.
The level of noise entering a person’s ear, when hearing protector is worn as directed, is closely approximated by the difference between the A weighted environmental noise level and the NRR.
- The environmental noise level as measured at the ear is 92 dBA
- The NRR is 30 decibels (dB).
- The level of noise entering the ear is approximately equal to 62 dB
For noise environments dominated by frequencies below 500 Hz the C-weighted environmental noise level should be used. Although hearing protectors can be recommended for protection against the harmful effects of impulsive noise, the Noise Reduction Rating (NRR) is based on the attenuation of continuous noise and may not be an accurate indicator of the protection attainable against impulsive noise such as gunfire.
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