GB/T 7584.1-2026 Active

This document describes a subjective method for measuring the sound attenuation of hearing protectors at the hearing threshold. This method is a laboratory method used to obtain reproducible sound attenuation values under controlled measurement conditions, reflecting the sound attenuation performance when the user wears the hearing protector in the same manner as the subject. For more representative on-site performance, the method in ISO/TS 4869-5 can be used to obtain this performance. This test method obtains data at low sound pressure levels (close to the hearing threshold), which also reflects the attenuation values of hearing protectors at higher sound pressure levels. However, for sound pressure amplitude-sensitive hearing protectors, this method is not suitable when the sound pressure level exceeds the critical amplitude at which their sound pressure characteristics take effect. Because at these sound pressure levels, the sound attenuation values of hearing protectors are often underestimated using the method specified in this document. Note: When testing low-frequency sound attenuation below 500 Hz in a plugged-ear situation, the sound attenuation values will be overestimated by several decibels due to physiological noise masking the hearing threshold of the plugged ear.