声学.噪声诱发的听觉损耗估计

[中文适用范围]： 本国际标准规定了一种计算由于不同水平和持续时间的噪声暴露而引起的成人听力阈值水平预期噪声引起的永久阈值变化的方法；当通常测量的听力频率或这些频率的组合的听力阈值超过一定值时，它为根据各种公式计算听力残疾提供了基础。 [外文原描述]： ISO 1999:2013 specifies a method for calculating the expected noise-induced permanent threshold shift in the hearing threshold levels of adult populations due to various levels and durations of noise exposure; it provides the basis for calculating hearing disability according to various formulae when the hearing threshold levels at commonly measured audiometric frequencies, or combinations of such frequencies, exceed a certain value. The measure of exposure to noise for a population at risk is the noise exposure level normalized to a nominal 8 h working day, LEX,8h, for a given number of years of exposure. ISO 1999:2013 applies to noise at frequencies less than approximately 10 kHz which is steady, intermittent, fluctuating, irregular. Use of ISO 1999:2013 for sound pressures exceeding 200 Pa (140 dB relative to 20 µPa) is recognized as extrapolation.