Each item placed on the work surface interferes with the directional air flow, causing turbulence and eddy currents that allow contaminants to be drawn out of the hood. Even with highly volatile materials, as long as a container is properly capped evaporation will not add significantly to worker exposures. Unlike a fume hood, flammable materials storage cabinets provide additional protection in the event of a fire. Myth - The airfoil on the front of a hood is of minor importance. It can safely be removed if it interferes with my experimental apparatus.
Airfoils are critical to efficient operation of a fume hood.
With the sash open an airfoil smooths flow over the hood edges. Without an airfoil eddy currents form, causing contaminates to be drawn out of the hood. With the sash closed, the opening beneath the bottom airfoil provides for a source of exhaust air. To Report a Malfunctioning Hood Report air flow problems with general purpose or perchloric acid hoods to the Industrial Hygiene at 852-6670. Malfunctioning radioisotopes hoods should be reported to Sarah Hughes at 852-5231.