The Mine Safety and Health Administration (MSHA) has issued new safety recommendations for underground coal mines following the fire that broke out at AMCI’s Longview metallurgical coal mine on June 27, 2024. The fire was caused by the application of a large quantity of polyurethane foam used to fill a roof cavity in the mine. This incident marks the fourth uncontrolled heating event linked to polyurethane foam in the past four years.
Polyurethane foam, commonly used for void filling in mines, undergoes an exothermic chemical reaction during curing, producing heat that can ignite if not carefully managed. MSHA has highlighted that injecting large quantities of this foam can lead to underground mine fires, posing significant risks to miner safety.
In response, MSHA is urging coal mine operators to develop site-specific plans for using polyurethane foam. These plans should detail the appropriate placement of foam, injection volumes and rates, and include safety measures such as temperature monitoring and fire watch procedures. Operators are also advised to ensure that workers have personal protective equipment to guard against chemical exposures and are trained in recognizing the hazards associated with polyurethane foam.
Furthermore, the agency stressed the importance of adhering to the manufacturer’s instructions and cautioned against the use of polyurethane foam products for filling large voids that can generate hazardous levels of heat.
