Noise and Dust Survey in Mines

Abstract

Opencast and underground mining operations produce large quantities of dust as well noise due to increased mechanisation to augment production and enhance productivity to meet the demands of consumer industry. Exposure of miners to high concentrations of dust and noise may cause occupational health hazards like pneumoconiosis and noise induced hearing loss and other allied health risk. Health risk to miners from dust depends on dust size, concentration and duration of exposure whereas noise induced hearing loss depends on sound pressure level, frequency and exposure level of workers. Exposure of workers to dust concentrations and sound pressure levels beyond threshold limit values as prescribed limits by statutory enactments and guidelines may adversely affect the health of mine workers. To assess the status of dust concentrations and noise levels generated by various machines and exposure levels of workers, conduct of systematic dust and noise survey in mines is essential. It will help in assessing the situation vis-a-vis dust and noise standards so that effective dust and noise control strategies can be adopted to minimize their menace.
Keeping this in view, this project work was undertaken to carry out dust and noise survey in an iron ore mine of SAIL. From dust and noise survey carried out in Bolani iron ore mines, it was observed that:
-> The dust level at the mine site office was minimum (0.14 mg/m3) whereas the maximum dust level was found at the crusher plant area (3.1 mg/m3). The dust concentration at lump loading station, fine loading station, mine face and mine site office was less than safe working limit(3 mg/m3) whereas at the washing plant and crusher plant area were found more than the safe working limit.
-> The noise level at the secondary cone crusher was maximum (102.2 dBA) whereas at the control room minimum (76.2 dBA). The noise level at dumper, drill machine, drum scrubber, double deck screen and dewatering screen was more than 90 dBA which is maximum permissible limit for 8 hrs working period. Whereas the noise level at loading station, hopper, shovel, and control room was below the permissible limit 90 dBA. Hence we can say that the worker of the Iron Ore Mine, Bolani are working under high noise level more than the acceptable level.
->From the modelling of the Noise rating from Mamdani Fuzzy System, the noise rating for different machineries were determined and compared with the field data for the Noise Rating and it was found that the results were satisfactory.