Combustible dust fires and explosions have resulted in many process safety incidents that have caused multiple fatalities and injuries together with considerable property damage. According to the US Chemical Safety Board (CSB), 386 major incidents occurred from 1980 to 2017. They killed 178 people and injured 1021 people. The incidents came from a wide variety of industries.
Numerous lessons have been learned from the investigation of combustible dust incidents including:
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Dust hazards often are not understood and are unrecognized by companies operating facilities where dusts are present.
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Dust fires can occur both within and outside equipment. Fugitive dust emissions usually are responsible for fires and explosions in rooms and buildings where equipment that contains combustible dusts is located.
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Air movement generally lifts the finest, most hazardous dusts highest in a room or building where they deposit on elevated surfaces.
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Most dust explosions occur as a series of deflagrations leading to a series of explosions in stages.
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Secondary deflagrations usually are fueled by accumulated fugitive dust that has been suspended by the primary deflagration.
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Most large-loss explosions involving combustible dust have occurred because a small event produced an ignition mechanism and dispersion of accumulated fugitive dust in the interior of a building.
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Housekeeping often is the single most important measure a facility can take to reduce combustible dust hazards within a building.
These lessons must be taken seriously by companies that handle combustible dusts if the likelihood of future catastrophic incidents is to be minimized.