Dust collectors work by separating particulate matter from a flowing air stream. In most instances, the process involves three stages: the trapping of dust in filters; the pneumatic cleaning of the filters periodically; and the removal of collected dust by means of a rotary valve or pneumatic conveyor.

The concentration of flammable dust in and around filter elements and in the collection chambers is usually above the lower explosive limit. Periodic shaking or reverse jet pulsing produces additional dust clouds that increase the explosive hazard. All that's missing is a source of ignition.