The Stable Vortex® II Fume Hood is a high performance, low flow fume hood that delivers a superior level of safety for the user, while providing substantial energy savings for a laboratory facility. AHR Innovation Award Winner The Stable Vortex® II protects users from dangerous chemical vapors and dusts during laboratory experiments, regardless of sash movement or environmental airflow changes. The design is based on the principle that efficient and stable hood operation is determined by controlling the airflow pattern through the hood and not by the entry velocity of air in the sash opening. The hood creates a stable vortex in the upper chamber of the hood that eliminates the backflow of air (hood spill) through the sash opening, creating a safer working environment for users. It also effectively contains using significantly less airflow compared to conventional fume hoods. The design correlates with the intent of the ASHRAE 110-2016 containment test.