Designed to operate at low air volumes, Protector® XStream® Laboratory Hood uses patented features that work together to reduce concentrations of contaminants in areas behind sash opening and near user's breathing zone. Upper dilution air supply bathes sash interior with clean air, eliminating chemical fumes along sash plane, while Eco-Foil air foil with Clean-Sweep™ openings minimizes energy consumption. Operating Protector XStream at OSHA-approved 60 fpm consumes only 690 cfm.