Bedi Raman
Department of Mechanical Engineering, National Institute of Technology, Jalandhar, Punjab, India.
Ind Health. 2006 Jan;44(1):112-6. doi: 10.2486/indhealth.44.112.
Occupational Noise exposure has been linked with a range of negative health effects by various researchers. The resulting injury of occupational hearing loss is also a well recognized and global problem. To protect workers from hearing damage due to noise exposure and other related health effects, a vast store of knowledge has been accumulated till date about its nature, etiology and time course. There is still ignorance, amongst majority of people working in industries in developing and third world countries including India about ill effects of exposure to high values of noise. The study being reported here has been carried out in two textile plants located in Northern Indian state of Punjab. Equivalent sound pressure level L(eq) has been measured in various sections of these plants with the help of a Class-I type digital sound level meter. The noise spectrum has been evaluated with the help of 1/3 octave filter set. A cross sectional study involving 112 workers exposed to different levels of occupational noise has been conducted. The results of the study establish the fact that noise level in certain sections of the plants i.e Loom Shed, Spinning, Ring Frame, TFO Area is more than the acceptable limit of 90 dBA for 8 h exposure stipulated by OSHA. The noise level in other sections like carding, blow room, combing etc., although is less than 90 dB(A), but is quite higher than limits used for assessment of noise for community response. Octave band analysis of the noise shows the presence of high sound level in 4,000 Hz frequency range, which can be a major reason for causing occupational hearing loss. The results of the interview questionnaire which included a number of parameters reveal the following; (i) only 29% workers are aware about the effects of noise on health (ii) 28% workers are using ear protectors (iii) the satisfaction with the working environment is related to noise level, as workers exposed to comparatively less noise level report better satisfaction (iv) 70% of the workers reported that high noise level causes speech interference (v) 42% workers report the noise to be annoying. The study thus demonstrates the presence of gross occupational noise exposure in both the plants and the author believes that occupational noise exposure and the related effects in India is a widespread problem.
多位研究人员已将职业性噪声暴露与一系列负面健康影响联系起来。由此导致的职业性听力损失损伤也是一个公认的全球性问题。为保护工人免受噪声暴露及其他相关健康影响造成的听力损害,迄今为止,已积累了大量有关其性质、病因和病程的知识。在包括印度在内的发展中国家和第三世界国家,大多数在工业领域工作的人仍然对高噪声暴露的不良影响一无所知。此处所报告的研究是在印度北部旁遮普邦的两家纺织厂进行的。借助I类数字声级计在这些工厂的各个区域测量了等效声压级L(eq)。借助1/3倍频程滤波器组对噪声频谱进行了评估。开展了一项横断面研究,涉及112名暴露于不同水平职业噪声的工人。研究结果证实,这些工厂某些区域(即织布车间、纺纱车间、环锭细纱机、倍捻机区域)的噪声水平超过了美国职业安全与健康管理局(OSHA)规定的8小时暴露90分贝A的可接受限值。其他区域(如梳棉、清花、精梳等)的噪声水平虽然低于90分贝(A),但远高于用于评估社区反应的噪声限值。对噪声的倍频程分析表明,在4000赫兹频率范围内存在高声级,这可能是导致职业性听力损失的主要原因。包含多个参数的访谈问卷结果显示如下:(i)只有29%的工人了解噪声对健康的影响;(ii)28%的工人使用耳塞;(iii)对工作环境的满意度与噪声水平有关,因为暴露于相对较低噪声水平的工人报告的满意度更高;(iv)70%的工人报告高噪声水平会造成言语干扰;(v)42%的工人报告噪声令人烦恼。该研究因此证明这两家工厂都存在严重的职业性噪声暴露,作者认为职业性噪声暴露及其在印度的相关影响是一个普遍存在的问题。