"Respirable dust exposure has long been known to be a serious health threat to workers in many industries. In coal mining, overexposure to respirable coal mine

Respirable dust exposure has long been known to be a serious health threat to workers in many industries. In coal mining, overexposure to respirable coal mine d

Coal remains one of the principal sources of energy for the United States, and the nation has been a world leader in coal production for more than 100 years. Ac