000 00833nam a22001097a 4500
999 _c16255
_d16255
245 _aISO 4869-1:1990-Acoustics - Hearing protectors - Part 1: Subjective method for the measurement of sound attenuation
260 _aGeneva :
_bInternational Organization for Standardization,
_c1990.
300 _a12 p.
505 _aSpecifies a method for measuring sound attenuation at the threshold of hearing. The procedure is designed to yield values close to the maximum attenuation which are not normally attained under field conditions. The values reflect the attenuating characteristics only to the extent that users wear the device in the same manner as did the test subjects. Data are collected at low sound pressure levels but which are also representative of the values at higher sound pressure levels.
650 _aAcoustics
942 _cST