Noise Exposure of Operators at Different Operating Conditions of Heavy Earth Moving Machinery

摘要

This article reports the detailed noise analysis carried out at the operators' point for dumpers and dozers at various operating conditions. The study has been carried out on 16 dumpers of 85-t capacity (680-hp) and 4 dumpers of 410-hp. In case of dumpers, high noise level for the operating condition of the machine is observed beyond 600Hz frequency and for the dozers the same is observed beyond 100Hz frequency. Since high noise level in the frequency range of 1000Hz - 4000Hz affects the human ear the most, it is suggested to reduce the operators' exposure to such level of noise. In case of dumpers, it is suggested to reduce the operators' exposure to high frequency noise by proper design of cab (leak proof). The cab effectiveness can be found out by comparing its noise spectrum to that of a new machine at operators' position. For machines, which are not equipped with operators' cab as in the case of dozers, it has been suggested to provide suitable earplug/ear muffs so as to protect the possible hearing damage, which may occur when exposed constantly to such noise levels.