Hearing Threshold Level Inworkers of Meybod Tile Factory

Occupational exposure to excessive noise is commonly encountered in a large number of industries in Iran. This study evaluated the hearing threshold and hearing loss in Meybod tile factory workers.

This cross-sectional study included 371 tile factoryworkers during summer and autumn of 2005. Current noise exposure was estimated using sound level meter .A specially formatted questionnaire was used. Totoscophc examination and conductive air audiometery were used to assess the hearing loss in each subject .Finally data was analyzed using SPSS version 11.5.

Occupational noise increased mean of hearing threshold at all frequencies which was significant at 3, 4 KHz in both ears (p<0.05).Prevalence of hearing impairment at high and low frequencies were 39.2% and 46.5%.Prevalence of occupational NIHL was 12.9% and the odds of NIHL significantly increased with noise exposure of more than 10 years. The hearing threshold was worse in both ears of workers with tinnitus.

High prevalence of hearing loss and NIHL emphasizes on the necessity of hearing conservational programs in tile factory workers.