Abstract: As a preliminary step, the dirty filter is dried to remove substantially all moisture from the dust on the filter. The filter is then spun in a closed cabinet. Simultaneously, a jet of pressurized air is reciprocated in close proximity along the inner surface of the filter. Also at the same time, suction is maintained on the cabinet, to remove dust-laden air and assist in the dislodging of the dust from the filter paper. By the combined actions of spinning, close-coupled reverse air jetting, and suction, the dust can substantially all be removed from the dirty filter.