Noise induced hearing loss (NIHL) in wasit corporation textile industries

Abstract

Background: Noise Induced Hearing Loss (NIHL) is used to symbolize accumulative and persistent hearing loss due to progressive exposure to high levels of noise for months or year. Design: A cross-sectional study. Setting: Al-Karama Teaching Hospital and Wasit Co. Textile Industries. Aims and objective: To specify frequency of hearing loss among workers in the knitting industry, to registration the level of the noise in the weaving department and to specify the realization about the impact of noise on the hearing. Materials and methods: From June to August 2011, the level of noise in the weaving department has been recorded. 200 workers had been sent to our hospital, interviewed according to already prepared questioner and audio logically assessed. Results and discussion: The mean level of noise at 12measurement points was 87-96dB. Which was greater than the allowable noise level for continuous 8 hours working per day? It has been established that 113 workers had NIHL, 29% of hearing loss (the greater percentage) was in the mild category (26-40dB) at high frequency (4-6KHz) group and the minimal NIHL notch within 2 kHz and 4KHz were 6% and 22% from the workers respectively. The hearing difficulty was not the most common complaints 29.4%, while ear discomfort was 55.4% and tinnitus was 43%, because NIHL usually include the high frequencies at first hence the worker can promote the NIHL and he didn't complain from loss of hearing. No one used the personal noise protective devices (PPD) and only 44 workers (24%) (P-value≤ 0.1) who considers that the noise is a hazard on health. Conclusion: Wasit Co. Textile Industries Noise measurement is greater than the allowable noise scale for 8 hours. NIHL can be developed many years before worker will complain from hearing loss.