Quantitative Risk Assessment and Protective Measures of Noise-induced Hearing Loss in a Ore Beneficiation Workshop of an Iron Mine
In order to effectively control the noise hazard of an iron mine,aiming at the problem of the influence degree of the noise exposure level on workers'hearing loss in ore dressing workshop,based on the study of noise exposure level in ore dressing workshop,the quantitative risk assessment method is used to determine the risk of hearing loss caused by noise exposure in each post of ore dressing workshop,with noise exposure time and the exposure intensity as independent variables,and the risk of high frequency hearing loss and occupational noise deafness in each post as dependent variables.The results show that the noise exposure intensity of ore dressing workshop is 86.4 to 94.6 dB(A),which exceeds the occupational ex-posure limit.In the absence of ear protectors,after 30 years of exposure,the risk of high-frequency hearing loss is 21.3%to 31.0%in the ball miller(one stage),the ball miller(two stage),breaker(fine crushing)and fitter positions,and the risk of occupational noise deafness is 2.7%to 12.7%,all of which are high risks.The remaining positions are negligible or moderate risks.In the case of using ear protectors,the risk of noise deafness in each position is acceptable or negligible.It is suggested that the mineral processing work-shop should adopt sound insulation and noise reduction measures to improve the working environment and strengthen the individual protection level,so as to reduce the noise exposure risk of workers.