An initial (primary) explosion in processing equipment or in an area where fugitive dust has accumulated may dislodge more accumulated dust into the air, or damage a containment system (such as a duct, vessel, or collector). As a result, if ignited, the additional dust dispersed into the air may cause one or more secondary

The first three elements are those needed for a fire, i.e., the familiar "fire triangle": Combustible dust (fuel); Ignition source (heat); and, Oxygen in air (oxidizer).An additional two elements must be present for a combustible dust explosion: Dispersion of dust particles in sufficient quantity and concentration; and, Confinement of the dust cloud. If one