DOSE ASSESSMENT OF INTERMITTENT NOISE EXPOSURE OF COAL MINERS

Abstract

Dose assessment of intermittent noise exposure of coal miners is carried out. The effectiveness of selecting personal hearing protection equipment (PHPE) by the value of the equivalent sound pressure level and by the dose assessment is compared. The proposed dose assessment procedure allows taking into account the transmitted energy during the action of noise, estimating the total noise load and correlating the obtained values with the excited biological effects. Since the acoustic efficiency of the PHPE selected based on special evaluation of working conditions is insufficient to protect workers from the increased-level noise, selection of the PHPE based on the dose assessment is carried out to ensure safety. It is found that the use of the PHPE selected according to the dose assessment can reduce the dose of noise received by miners during the shift down to allowable values. To ensure the safety of workers under the influence of the noise factor, the operators of mining and drilling machines should use the PHPE with an acoustic efficiency of 25 dB and 35 dB, respectively, which exceeds the acoustic efficiency of the PHPE selected from the special evaluation of working conditions by 10 dB. The dependence of the absorbed noise dose of coal miners in the increased noise exposure on the acoustic efficiency of the PHPE is revealed. It has been found that in order to prevent occupational diseases (sensorineural hearing loss) in underground miners, it is necessary to select the personal protective equipment for the hearing organ taking into account the dose assessment.