Noise Induced Hearing Impairment Amongst Industrial Hand Grinder Operators in Tractor Auxiliary Industry

摘要

Grinding operation is very important part of any automobile or sheet metal work industry. A study was conducted in tractor auxiliary industry to assess the noise level, in which the industrial hand grinder operator is working. Arphi 500 MKIII portable audiometer was used to measure noise induced hearing loss caused to operators because of excessive noise of hand grinder operation. Operators were audio metrically examined before and after a day's work to find temporary threshold shift. Their threshold of hearing was compared with that of normal person of that age group to find out permanent threshold shift. Noise level of grinding operation ranged from 100.91 to 113.31 dB(A). TTS of all the workers and also minor to major PTS at all audiometric frequencies were observed. A dip at 4 kHz was observed in all audiograms. All the audiograms were convex downward indicating more loss at higher frequencies. Posture of worker while working was an important aspect to explain the difference of TTS and PTS w.r.t. left and right ears. Some ways and means were suggested to protect workers from ill effects of noise and a few immediate possible suggestions were implemented. Results were encouraging and there was appreciable reduction in worker's noise exposure level (1.96-21%). Also, the general ambience of working environment improved tremendously with drastic cut in worker complaints.