Laboratory facilities remain expensive to operate becauseof the extraordinary volume of once-through exhaust airrequired by chemical fume hoods. Traditionally, laboratoryfume hood operation is perceived as a laminar flow process tocapture and contain contaminants inside the hood, and relieson face velocity to establish the volume of air required whenthe hood is in use. Conversely, vortex fume hood operation isunderstood as a dilution process that utilizes turbulence todissolve and contain contaminants in the airstream andemploys air changes per minute (independent of face velocity)to establish the volume of air that passes through the hood.With improved performance, the vortex hood requires approximatelyhalf the volume of exhaust air used by the traditionallaboratory fume hood.