The Grease Trapper pollution control unit uses a three-stage mechanical filter arrangement to remove grease and smoke particles from the exhaust air at an economical initial cost. Independent pressure switches signal when any of the three filter stages need replacing, taking the guess work out of maintaining the equipment. The Grease Trapper incorporates activated carbon panels to remove odor molecules prior to discharging the air, reducing the impact of the kitchen exhaust to the surrounding area.