Monitoring and Sampling Approaches to Assess Underground Coal Mine Dust Exposures compares the monitoring technologies and sampling protocols currently used or required by the United States, and in similarly industrialized countries for the control of RCMD exposure in underground coal mines. This report assesses the effects of rock dust mixtures and their application on RCMD measurements, and the efficacy of current monitoring technologies and sampling approaches. It also offers science-based conclusions regarding optimal monitoring and sampling strategies to aid mine operators' decision making related to reducing RCMD exposure to miners in underground coal mines.