Bench-top Protector Pass-Through Laboratory Hoods may be operated from either side. When mounted in an island or peninsular configuration, the hoods' unobstructed viewing from either side make them ideal for conducting chemistry demonstrations or to observe students while using the hoods. An optional 15 inches× 24 inches right–side mounted, clear tempered safety glass viewing window enhances visibility. The hood can also be installed in a wall between two rooms to permit safe transfer of chemicals and experiments. An audible sash alarm sounds when both sashes are opened at the same time. Ergonomic air foil with aerodynamic Clean-Sweep airflow openings sweeps the work surface for maximum containment. Clear, vertical-rising, tempered safety-glass sashes provide maximum visibility. Chemical-resistant, polyester-reinforced composite panel liner surpasses all national codes for flame spread and has a bright white surface for excellent light reflectivity.