scope:

This standard specifies the laboratory psychophysical procedures and means of reporting results for measuring the noise reducing capabilities of wearable devices that are used to protect the human auditory system against excessive sound.

Purpose

The purpose of this standard is to describe procedures designed to determine real-ear attenuation measured by psychoacoustic tests at hearing threshold on human subjects. (Footnote 1) The methodology is intended to yield optimum performance values which may not usually be obtained under field conditions. Optimum performance values have been chosen because they can be repeated consistently for reliable rank-ordering of protectors. The values will depict the noise-reducing capabilities of hearing protectors only to the extent that users wear the devices in the same manner as did the test subjects.