Hearing protector performance--an update.

A single-number descriptor, the A-weighted sound pressure level, has been used widely during the last 10 years for the assessment of noise exposure levels. Prior to that time octave band levels were the common means for describing noise exposures. Hearing protector noise reduction data have been presented in various ways to facilitate the calculation of exposure levels while wearing hearing protectors. This paper describes both single-number and octave band procedures for presenting hearing protector noise attenuation data and discusses advantages and disadvantages of each.