THE ESTIMATION OF THE PREVALENCE OF HEAR-ING-IMPAIRMENT FOR THE NOISE-EXPOSED POPULATION IN CHINA BASED ON ISO/DIS 1999.2

Based on the noise survey in China,the formula(H′=H N-HN/120 )of ISO/DIS 1999.2 ("Acous-tics-Determination of Occupational noise exposure and estimation of noise-induced hearingimpairment,1985 )was applied to the calculation of the hearing threshold level associated with age andnoise(HTLAN)of the noise-impaired people.According to the Gausscian distribution,when thenoise-exposure level L_(EX8h)was 85,90 ,95,100 dB and the hearing threshold frequency is from 0.5k to6kHz,the HTLAN of noise-exposed people withdifferent duration of exposure and its relation values tothe hearing threshold frequency associated with age(HTLA)were obtained.The ISO/DIS 1999.2 hasbeen proved to be applicable in China.