Mining Program Area: Hearing Loss Prevention and Noise Control
The purpose of the hearing loss prevention and noise control program is to reduce mine workers’ risk of noise-induced hearing loss.
The mining industry has the highest prevalence of hazardous workplace noise exposures (76%) among all industrial sectors (Tak and Calvert, 2008). Despite engineering and administrative controls implemented to reduce noise, mine workers continue to exhibit a high prevalence (24%) of hearing difficulty (Tak et al., 2009). Developing engineering controls is the most effective way to reduce hazardous noise exposures, but the technical complexity of this task exceeds the abilities of mining machine manufacturers without the support from the National Institute for Occupational Safety and Health’s (NIOSH) Office of Mine Safety and Health Research (OMSHR).
The hearing loss prevention and noise control program seeks to answer the following questions:
- What are the primary noise hazards that place mine workers at risk for noise-induced hearing loss?
- For each hazard, what noise controls can effectively reduce the noise hazard?
- Currently, the program is investigating noise controls for continuous mining machines, roof bolting machines, longwall mining machines, underground metal mine load-haul-dumps and haul trucks, and the air carbon arc cutting and gouging process. These are the primary noise sources in underground coal and metal/nonmetal mines.
- What is the impact of OMSHR's solutions on noise exposure and hearing loss in the mining industry?
OMSHR’s program emphasizes exposure reduction through engineering controls, which is the most effective way to address hazardous noise. It also creates collaborations with manufacturers who will make the noise controls commercially available. Finally, the program fosters the commercialization of controls to obtain widespread implementation and maximum impact.
The program’s projects incorporate targeted contracts for specialized capabilities in acoustic modeling and mechanical fabrication to complement the in-house OMSHR capabilities. When outside expertise is available to move projects faster or to provide new capabilities it is used to help OMSHR researchers reach their goals more effectively. Some significant milestones are listed below:
- A dual-sprocket continuous mining machine chain was commercialized by Joy Mining Machinery in 2008 and was implemented on over 30% of the machines in the United States by 2012.
- A drill bit isolator based on OMSHR technology was commercialized by Corry Rubber and Kennametal in 2011.
- A dual-sprocket urethane-coated continuous mining machine chain was commercialized by Joy Global in 2012.