For noise environments dominated by frequencies below 500 Hz, the C-weighted environmental noise level should be used. Improper fit of this device will reduce its effectiveness in attenuating noise. Consult the above instructions for proper fit. 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. The Noise Reduction Rating (NRR) calculated from the attenuation data is 22dB. HEAROS ear plugs must be properly fitted to attenuate noise effectively. Refer to instructions.

Tested according to ANSI Specs S3.19-1974
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.

EXAMPLE:
1. The environmental noise level as measured at the ear is 92 decibels dB(A).
2. The NRR is 22 decibels (dB).
3. The level of the noise entering the ear is approximately 70 dB(A).