The best way to reduce or eliminate one’s exposure to airborne substances is the proper use of well designed engineering controls. With engineering controls, safety is designed into the process and there is less reliance upon the skill and vigilance of the worker. Examples of engineering controls include chemical fume hoods, glove boxes and remote automation. Remote automation keeps a worker away from the dangerous process and protects the worker by distance. For laboratories on campus, fume hoods are the most important and common type of engineering control.
A biosafety cabinet is not a chemical fume hood. Their motors are not explosion-proof and a biosafety cabinet should never be used for working with flammable chemicals. If you are working with volatile toxic chemicals, special care needs to be taken because some biosafety cabinets do not vent exhausted air from the building; they merely filter the air to remove airborne microbes. Chemical vapors and gasses easily pass through the filter and are dispersed back into the room.
A fume hood is usually a permanent installation in the laboratory, and it should have a Marquette University fume hood evaluation sticker affixed, and dated within the past year. A biosafety cabinet is a stand-alone piece of equipment in the laboratory, sometimes it is connected to the building’s exhaust ventilation. Biosafety cabinets should also be certified on an annual basis.
For more information on fume hood guidelines, please refer to the University’s Chemical Fume Hood Testing Procedures.