Development and Evaluation of Fire Barriers to Reduce Fire Hazards on large mining Equipment

The National Institute for Occupational Safety and Health has developed and evaluated various fire barriers for their effectiveness in preventing the spraying of pressurized hydraulic fluids onto simulated turbocharger hot surfaces, and in preventing the ignition of flammable vapors and mists onto barrier outer surfaces. This initial study, however, needs to be followed by a larger investigation that deals with barrier effectiveness in preventing or reducing hydraulic fluid fires within compartments of operating equipment, and barrier physical endurance under hostile environments within compartments. Some of the barriers were also evaluated for their effectiveness in suppressing simulated turbocharger fast-developing fires (initial fires, 32 kW). For the evaluation, modeled engine compartments with simulated turbocharger surfaces of 600°C, initial fires of 32 kW, and a pressurized hydraulic fluid spray system, were used. Also, conceptualized designs of some of the fire barriers, set within the compartments of typical mining equipment, have been reported to provide further guidance toward barrier fabrication and installation. The fire barriers included a parachute silica cloth barrier lined with flexible stainless steel foil; a one-panel insulated stainless steel barrier with a water-spray system; a foldable multi-panel insulated stainless steel barrier; and, an open–close steel strip barrier. Results show that all four fire barriers were effective in preventing the spraying of pressurized hydraulic fluids onto simulated turbocharger hot surfaces. Most of the barriers were also effective in preventing the ignition of flammable vapors and mists onto barrier outer surfaces. Results also show that the parachute barrier and the one-panel barrier with a water-spray system were effective in suppressing simulated turbocharger initial fires of 32 kW.