噪音與振動對航太工業員工聽力之影響

Combined Effect of Noise and Vibration on Hearing Loss of Aircraft Assembly Workers

劉秋松(Chiu-Shong Liu) ； 戴志展(Chih- Jaan Tai) ； 賴俊雄(Jim-Shoung Lai)

《Mid-Taiwan Journal of Medicine》 6卷3期 (2001/09) Pp. 147-156

https://doi.org/10.6558/MTJM.2001.6(3).4

摘要

Background. Hearing loss is a well documented occupational disorder among workers exposed to excessive vibration and noise levels greater than 85 dB. In many industries, the hazards of noise and vibration usually co-exist. The purpose of this study was to assess the exposure of noise and vibration in the aerospace industry and to investigate the combined effects of noise and vibration on hearing loss.
Methods. We conducted a cross-sectional study of employees working at an aircraft assembly factory in October 1998. The 1002 participants were divided into 3 groups according to the kinds of exposure: (a) noise and vibration (548), (b) noise only (332), (c) no exposure (122). Past medical history, occupational history and other factors which might affect hearing were recalled by questionnaire. Noise sound levels and vibration were assessed by standard methods in the workplace. The hearing threshold was measured by pure tone audiometry, and the methods used for statistical analysis included Chi-square, ANOVA, multiple regression analysis and logistic regression with the aid of an SAS package.
Results. The equivalent sound level (Leq) at various working places ranged from 82 to 108 dBA while the maximum sound level ranged from 86 to 130 dBA. A total of 194 (27.8%) subjects were diagnosed as having hearing impairments. Hearing loss at high frequencies (4K, 6K Hz) was considerably greater than that at low frequencies (O.5K, l K, 2K Hz). After adjusting for age and sex, the risk of hearing impairment due to exposure to high noise levels (＞ 90 dB) and medium noise levels (85-90 dB) were 32.6 (95%CI:13.0-81.7) and 7.9 (95% CI: 4.4-14.3) respectively. The risk of hearing impairment due to exposure to high vibration levels was 2.8 (95% CI: 1.3-5.8) compared with the low vibration level group.
Conclusions. The noisy environment of the aerospace industry is relatively severe. However, the vibration levels at the studied factory is still below the ACGIH recommended levels. The prevalence of hearing loss among the workers in our study was 28%. Control of the noise and vibration levels is necessary in order to prevent further health damage.

關鍵字

聽力損傷,噪音,振動

並列摘要

Background. Hearing loss is a well documented occupational disorder among workers exposed to excessive vibration and noise levels greater than 85 dB. In many industries, the hazards of noise and vibration usually co-exist. The purpose of this study was to assess the exposure of noise and vibration in the aerospace industry and to investigate the combined effects of noise and vibration on hearing loss.
Methods. We conducted a cross-sectional study of employees working at an aircraft assembly factory in October 1998. The 1002 participants were divided into 3 groups according to the kinds of exposure: (a) noise and vibration (548), (b) noise only (332), (c) no exposure (122). Past medical history, occupational history and other factors which might affect hearing were recalled by questionnaire. Noise sound levels and vibration were assessed by standard methods in the workplace. The hearing threshold was measured by pure tone audiometry, and the methods used for statistical analysis included Chi-square, ANOVA, multiple regression analysis and logistic regression with the aid of an SAS package.
Results. The equivalent sound level (Leq) at various working places ranged from 82 to 108 dBA while the maximum sound level ranged from 86 to 130 dBA. A total of 194 (27.8%) subjects were diagnosed as having hearing impairments. Hearing loss at high frequencies (4K, 6K Hz) was considerably greater than that at low frequencies (O.5K, l K, 2K Hz). After adjusting for age and sex, the risk of hearing impairment due to exposure to high noise levels (＞ 90 dB) and medium noise levels (85-90 dB) were 32.6 (95%CI:13.0-81.7) and 7.9 (95% CI: 4.4-14.3) respectively. The risk of hearing impairment due to exposure to high vibration levels was 2.8 (95% CI: 1.3-5.8) compared with the low vibration level group.
Conclusions. The noisy environment of the aerospace industry is relatively severe. However, the vibration levels at the studied factory is still below the ACGIH recommended levels. The prevalence of hearing loss among the workers in our study was 28%. Control of the noise and vibration levels is necessary in order to prevent further health damage.

並列關鍵字

hearing impairment,noise,vibration