Smoke and hot air rise. To ensure optimum air filtration efficiency, the NoSmokeKing™ system employs a “ceiling sweep” technique to capture contaminated air as it rises. Contaminated air is drawn into the air cleaner through the return air ductwork via strategically located ceiling grilles. The air is cleaned and redistributed into the room through the supply air ductwork and the curved blade air grilles. These curved blade grilles direct purified air back along the ceiling toward an associated return air grille, creating the most effective flow pattern for quick removal of contaminated air. Other air cleaning systems utilize a far less effective air flow pattern known as Coanda air flow. This air flow pattern circulates contaminated air throughout the room before it is returned to the air cleaner. Each NoSmokeKing™ system supply and return grille layout is custom designed to insure maximum performance.