Dapper Ducts' duct cleanings boost indoor air quality by flushing mold, bacteria, and dust mites out of ventilation-system hidey-holes. First, technicians will cut an access hole in the main ductwork and attach a negative air machine before removing vent covers, cleaning grills, and plugging vent covers with foam so debris doesn't fly out. Then, Dapper Ducts' cleaners will aim an air compressor down each shaft, attacking stubborn encrustations with 200 pounds of pressure per square inch. Debris dislodged in this airy onslaught swirls down to the main vent, where a high-powered vacuum slurps it up. After each duct has been air-scrubbed, technicians reseal access holes with prefab sheet-metal doors that can be reopened the next time the ducts need to be serviced. Finally, they'll perform a last check to make sure they've left all areas clean and free of Funyuns.