The acoustic model acts as the link between the technical parameters and the resulting noise exposure of affected people. Probst highlighted the power of noise mapping which lies in the completeness of an acoustic model. Prediction based on acoustic and terrain modeling currently dominates research in environmental propagation of noise. In the west, noise mapping has been more widely used in the field of traffic and city noise modeling. Assessment of environmental noise is traditionally based on measurement of noise levels at receiver points, which neglects the sources which emanate the sound energy. This could be a reason why it is so difficult to provide an effective noise control measure through either noise control engineering or business process reengineering based on such measurements. All the above methods represent either an area or an individual under study and do not represent the overall scenario of the noise level distribution. For example, area noise monitoring is used to measure noise level of a particular area, whereas personal noise dosimetry is used to measure the percentage of noise dose to which a person is exposed during movements in different noisy or quieter areas during a working shift in the plant or within the mines. Various methods are used for assessing noise level in mines. The Central Government in February 2011 has also declared NIHL as notified disease under the Mines Act, 1952. This affected population was found to vary from 12.4% to 25.7% in various mines. In India, health surveillance studies conducted by National Institute of Miners’ Health (NIMH) signaled that many workers engaged in mining operations might be suffering from NIHL. Some of these effects, for example, tinnitus, and noise induced hearing loss (NIHL), reduced performance, sleeping difficulties, disturbance in conversation, annoyance or stress, etc. Exposure to noise leads to multiple adverse effects on physical and mental state of the mining community as a whole. Occupational noise exposure because of deployment and operation of these machines and plants is a major health hazard that affects millions of mine workers as well as the residential areas in and around the mining complexes. The problems of noise in Indian mines exist since long and practically no trend in improvement in the working environment is visible. The spatial distribution of mining activity also changes faster nowadays due to faster mining with more machines at work. Due to improvement in mechanization and continuous operation in mines, the equipment inventory has undergone a substantial change. Noise is recognized as a major pollutant of the mining environment.
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