The issue of combustible dust and its associated hazards (fire, deflagration, explosion) has existed for hundreds of years throughout numerous processes and equipment. However, it is only recently that the topic of combustible dust has become one of the primary concerns and focal points in the field of safety and health. Although combustible dust fires and explosions have occurred as early as 1785 and continue to occur to this day, most safety and health professionals still perceive combustible dust hazards as low priority and low risk. However, this perception has begun to change after several high-profile combustible dust accidents and fatalities, as well as increased enforcement of combustible dust hazards by the Occupational Safety and Health Administration (OSHA) and other Authorities Having Jurisdiction (AHJs) (e.g. fire marshals/departments, insurance firms/carriers, etc.).
To alleviate the hazards posed by combustible dusts, the National Fire Protection Association (NFPA) began developing several standards to address combustible dust and combustible particulate solids. Specifically, NFPA has addressed combustible dust hazards for flour and pulverized fuels and individual industry sectors as far back as the 1920s and 1930s. However, it was not until 2003 that users from all sectors comprehensively examined the specific requirements contained in the four major NFPA combustible dust standards (NFPA 61, NFPA 484, NFPA 654 and NFPA 664).
