Patent ID: 7318771

Claim:
An air-isolator fume hood comprising: a) a hood having: i) a containing space for a pernicious gas to be exhausted; and ii) an opening located in a side surface; b) a sash adjustably connected to the hood and selectively adjusting a height of the opening, the sash having an air pipe extending through an interior thereof and providing an input air, the sash is movable between closed and open positions; c) an exhaust outlet having a suction slot connected to the hood and communicating with the containing space, the suction slot is located on a bottom of the opening below the air pipe of the sash; d) a blower connected to an exit end of the exhaust outlet and exhausting the pernicious gas; and e) a screen located on a surface of the hood for supplying air, wherein the input air flowing through air pipe of the sash and an air supply flowing through the screen are flowing simultaneously with an exhaust air withdrawn by the blower, wherein the blower forming an air curtain and preventing the pernicious gas from being exhausted through the opening, wherein the air pipe of the sash communicating with the exhaust outlet and providing the input air when the sash is located in the open position, the closed position, and any position there between.