Strategies for noise control in the mining of hard rock and processing of sedimentary rock

M.Tech. (Extraction Metallurgy)Abstract: Occupational noise has been recognised as being one of the major causes of many adverse health effects worldwide. Long exposure to high noise levels is believed to have resulted in considerable physiological and social changes in the life of the person exposed, particularly in the form of noise-induced hearing loss. Noise-induced hearing loss (NIHL) has over the years become a critical issue in most industries around the world. According to Mizan and colleagues, the iron and steel industry has been identified as one of the highest industry risk in terms of NIHL in South Africa (Mizan, et al., 2014). Furthermore, the South African mining industry has been spending millions of rands in compensations and claims due to NIHL. This has made occupational noise a major problem in South Africa, where the South African Department of Labour issued regulations prescribing all employees exposed to a noise exposure level greater or equal to 85 dBA to undergo medical surveillance. This study was conducted in two different mining sites, notably Wessels Mine (Northern Cape) and Fikale Moriti Sandstone Mine of Qwaqwa (Free State). Wessels Mine is one of the biggest underground manganese mine in the country, and Fikale Moriti is one of the most successful artisanal small scale sandstone mine in the Qwaqwa region. At Fikale Moriti, focus was placed on the processing plant, where the greatest amount of noise was generated, as compared to the mining area, where the noise produce was below the threshold limit (85 dBA). The primary objective in this study was to investigate occupational noise and its effect on employees in the two mining operations cited above. The researcher aimed, in so doing, to develop and recommend strategies that will help the mines further control the noise hazard. Controlling noise will improve work’s conditions that will reflect positively on the health and availability of the workers. In order to do this, a review of literature was performed to ascertain what was known on the subject, and control that was already in place through previous research work. The process that ensued entailed elaborating a strategy for the collection, analysis and interpretation of data both from Wessels Mine and Fikale Moriti sandstone. The study made use of occupational noise survey as method to quantify the noise level at both mining operations and work practice observation to observe compliance from noise standards. A review of audiometric testing results of employees was also performed, in order to establish the prevalence of NIHL amongst Wessels Mine employees over the past years. In order to further control noise at the mines, the focus was given more to engineering control, with a little mention of administrative control. Upgrading to less noisy equipment, buy quite policy, upgrading to low-noise plant and making use of noise control equipment, such as silencers for fans and enclosures for crushers, were among some of the solutions pose