NIOSH Mining Safety and Health Research

The mission of the Ventilation Program is to improve mine air quality and reduce explosion hazards by developing and implementing advanced scientific ventilation technologies and practices.

Recent explosions in underground coal mines resulted in 35 fatalities. Research is continuing to look for ways to prevent these explosions. Explosions can be prevented or mitigated by eliminating ignition sources, by minimizing methane concentrations and coal dust accumulations, by application of sufficient rock dust, and by using passive and active barriers to suppress propagating explosions.

NIOSH has classified diesel particulate matter (DPM) as a potential carcinogen where prolonged exposure to such contaminants can result in adverse health effects. Excessive levels of methane gas, on the other hand, can undermine the safety of the underground work force. Available methane control systems have been challenged by recent mining developments which include increased face advance rates, increased productivities, increased panel sizes, and more extensive gateroad systems. High levels of methane and other airborne contaminants in underground workings are often most easily controlled through dilution with increased ventilation airflow. Other control measures include premining drainage of methane and improved seal and stopping designs to maintain separation of intake and return air courses.

Research is also being conducted on means to limit the spread of smoke and other contaminants in the event of a belt fire. This includes investigating the use booster fans for pressurizing an intake escapeway, improving escapeway integrity and reducing leakage from the belt entry through improved stopping construction techniques. These tasks are in direct response to the research recommendations of the Technical Study Panel on the Utilization of Belt Air and the Composition and Fire Retardant Properties of Belt Materials in Underground Coal Mining.