This statement concerned the occupational safety and health aspects of increased coal production, the conversion of oil and gas fired boilers to coal, and proposed coal conversion technologies. Studies continued to show that coal mining was one of the most hazardous occupations in the United States. Coal miners have excessive rates of chronic bronchitis and airway obstruction. Coal workers' pneumoconiosis continued to be a common finding in morbidity studies. Underground mining accounts for 82 percent of mining fatalities and 85 percent of nonfatal injuries. Increasing the production of coal would require that the coal mining population be increased from the current number of 191,000 to 308,200. It was thought that most of this increased production will come from surface mining, which was statistically safer than underground coal mining operations. Changes in mining techniques would also impact on the health of the miners. The introduction of diesel powered equipment into coal mines was of particular concern due to the possible health effects of long term exposure to a combination of coal dust and the gases and vapors of diesel exhaust. Current standards for exposures were based on exposures to single agents at a time, which was not the condition in which the coal miner finds himself. Conversion to coal fired power generation facilities would increase the public health hazards of emissions from coal combustion. Pretreatment steps designed to cut down on this hazard were briefly discussed. Hazards to workers involved with large scale coal conversion technology included exposure to chemical carcinogens, toxic inorganic gases, noise and heat stress.