Assessment of heavy earth-moving machinery noise vis-a-vis routine maintenance

摘要

Exposure to noise from various types of equipment/machinery has been identified as a critical health hazard for personnel working in the Indian mining industry. Heavy Earth Moving Machinery (HEMM) used in mines has been identified as a major source of noise, and several earlier investigators have proposed various types of retrofit measures on these machines to reduce noise. The present work was taken up with the objective of evaluating the noise generation characteristics of HEMM as influenced by periodic maintenance. Detailed noise measurements were carried out in a large open pit coal mine located in India. The effect of maintenance on noise production was assessed for ten dumpers and three dozers by measuring the A-weighted one-third-octave band sound pressure levels after the machines had been subjected to maintenance at the end of 300 hours, 500 hours, 750 hours and 1000 hours of use. Measurements were also carried out to assess the effect of maintaining specific HEMM systems noise characteristics at 1000 hours. Assessment of sound pressure levels at each periodic maintenance revealed major sound level reductions with 1000 hours maintenance. The data also identified the major noise generating systems in HEMM as air systems, exhaust systems, cooling systems and fuel systems. (C) 2006 Institute of Noise Control Engineering.