The paper deals with noise induced health risk assessment study in Gas Compressor Stations (GCSs) where sound level varies between 85 to 105 dBA. On routine audiometry test survey on 200 employees working in GCSs, approximately 6% of them were found to have been affected due to noise induced illness. Thereafter a joint team comprising experts from HSE cell and labour union representatives carried out survey of 19 such stations, identified the root causes and suggested remedial measures (both technical and administrative decisions). The entire case study was a unique approach of participation of Labour Union in Management to resolve HSE related problem.
The fact that noise can present a severe work hazard, if exposed to high decibel environment for prolonged period is well recognized. One of the major stresses with which today's worker must cope is excessive noise exposure. Noise is responsible for hearing loss, it interferes with communication and also with thought process. Noise interferes with sleep, causes anger and frustration and has been implicated as a contributor to various psychological and physiological problems. However, it is not a problem beyond control. Technology available today can reduce the hazard through engineering control, administrative control and use of protective equipment. By recognizing hazard level and using various methods of control, damage to hearing can be avoided.
As a part of oil exploration and production activities, Gas Compressor Station (GCS) have been set up in OIL INDIA LTD. (O.I.L.) since 1963 at different locations to handle associated and non-associated natural gas for consumer's use, enhanced oil recovery purpose besides production of LPG. 19 such stations are in operation now which houses minimum of two compressors to twelve compressors depending on the requirements. These gas compressors which are in operation round the clock are either motor driven or gas engine driven with the following ratings.
Pressure: Booster Compressor (17 to l9kg(cm2), Lifter Compressor (90 – 100kg/cm2) and injector Compressor (240–250 kg/cm2) respectively.
At the inception of all compressor stations which were set up in early 60s till middle of 70s, one or two compressors were housed in each station with the operator's room situated within the classified hazardous zone area (i.e. zone-II). Within few years after commissioning of each station, more compressors were added but the operator's room remained at the same place where it was located initially. It did not have sufficient in built attenuation measures to keep sound level below 80 dBA.The operator's room did not have the provision of approved type forced mechanical ventilation system due to which crew members often used to keep doors & windows open thereby became the receiver of sound very close to threshold limit valve sometimes above.
The case study which was conducted over a period of two months in all the 19 stations is an unique example of participation of Labour Union in Management function to resolve one of the most sensitive and complicated HSE problem in O.I.L. The study has given practical solution acceptable to both aggreved employees & Management as well which is under implementation now.