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Polyurethane Foam Fire Hazard - Safety and Health Alert

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Safety and Health Alert

Polyurethane Foam Fire Hazard

On June 27, 2024, a fire occurred in an underground coal mine after a large quantity of polyurethane foam was injected into a roof cavity. This is the fourth uncontrolled heating event attributed to polyurethane foam application in 4 years. Polyurethane-based foam products produce heat from an exothermic chemical reaction. Injecting large quantities of polyurethane to fill voids can cause underground mine fires.

Best Practices
  • Develop a Site-Specific Plan for Void Fills. The plan should address appropriate formwork (placement of foam), injection volume and rates, personal protective equipment for chemical exposures, temperature monitoring, fire watch, and storage and handling.
  • Follow manufacturer’s instructions.
  • Use the Proper Product. Do not fill large voids with polyurethane foam products that generate a hazardous amount of heat.
  • Train Miners. Miners working in the application of polyurethane foam should be trained in the hazards, safety precautions, and manufacturer’s Safety Data Sheets (SDS).