Mining Publication: The Development of a Damped Drill Steel to Reduce Roof Bolting Machine Drilling Noise

Among underground coal miners, hearing loss remains one of the most common occupational illnesses. In response, the National Institute for Occupational Safety and Health (NIOSH) conducts research to reduce the noise emission of underground coal mining equipment, an example of which is a roof bolting machine. Field studies support the premise that, on average, drilling noise is the loudest sound level to which a roof bolting machine operator would be exposed and contributes significantly to the operators’ noise exposure. NIOSH has determined that the drill steel radiates a significant amount of noise during drilling and has conducted research to evaluate a damped drill steel to reduce noise radiation. The paper documents the research to date of this damped drill steel. Laboratory testing confirms that the concept of a damped drill steel would reduce sound levels generated during drilling, and by extension, operator noise dose exposure.