Air is then filtered and/or treated by the building’s exhaust system before exiting the facility.
Fume hoods reduce potential exposure hazard to personnel, including contaminant concentrations near the edge of the sash. Fume hoods offer no protection to the product or environment.
Any toxic or volatile (tendency of chemical to vaporize) chemical must be used inside of a chemical fume hood to lower the chances of inhalation exposure. Specially designed fume hoods are required to provide protection from radiological hazards.
The “roll” of air which forms inside a fume hood immediately behind the sash can be a reservoir for contaminants. Air recirculates at that location rather than exiting the hood immediately, so contaminant concentrations may be higher in the “roll’ than at other point inside the hood.
The matter is of some concern, because the roll is close to the breathing zone of the scientist performing the work. Reducing this concentration can significantly reduce the hazard potential of any leakage.
Learn more by reading our white paper: Continuous-Flow Bypass For Improved Fume Hood Performance.