After chemical fume hoods are installed, they are checked by EHS personnel to ensure they meet ASHRAE 110 (American Society of Heating, Refrigerating and Air-Conditioning Engineers) standards for proper exhaust ventilation. The face velocity of the hood is measured in feet per minute (fpm) with an anemometer. As mentioned earlier, the fpm should be between 80-100 fpm for safe operation of the hood. It is the responsibility of Facilities Operations to arrange for testing and certifying the hood when the equipment is first installed. Supply and exhaust air flow should be in proper proportion to establish a negative pressure differential between the lab and the outside corridor. When operating, the hood's exhaust flow should be greater than the supply to create airflow movement from the hall into the lab to ensure airborne contaminants are contained.
Once the hood is certified, EHS performs fume hood inspections on an annual basis. All conventional hoods and specialty hoods are inspected individually. After initial post-installation checks, the annual inspection includes:
If at any time it is determined that the fume hood in your laboratory is not functioning properly, contact EHS for an immediate assessment.