Fire spurs MSHA safety alert on polyurethane foam

Arlington, VA — An underground coal mine fire stemming from the injection of polyurethane foam into a roof cavity has prompted the Mine Safety and Health Administration to issue a safety alert.

MSHA says the June 27 incident marks the fourth “uncontrolled heating event” tied to application of the foam in the past four years.

“Polyurethane-based foam products produce heat from an exothermic chemical reaction,” an agency press release states. “Injecting large quantities of polyurethane to fill voids can cause underground mine fires.”

Best practices related to the safe application of the foam:

• Develop a site-specific plan for void fills. Ensure the plan covers appropriate placement of foam, injection volume and rates, personal protective equipment for chemical exposures, temperature monitoring, fire watch, and storage and handling.
• Educate miners about hazards, safety precautions and manufacturer Safety Data Sheets.
• Follow manufacturer instructions.
• Don’t fill large voids with polyurethane foam products that generate a hazardous amount of heat.