Use of Fume Hoods

Proper use of laboratory fume hoods can be found in the Controlling the Risks of Chemical Hazards in Penn's Chemical Hygiene Plan.

Approved fume hood vendors

Laboratory fume hoods manufactured by Kewaunee Scientific Corporation, Mott Manufacturing, Baker, Labconco or Lab Crafters are preferred. Hoods from other manufacturers will be considered but must be pre-approved by EHRS.


Hoods shall be tested after installation and meet ASHRAE 110-most current Tracer gas test protocol with a rating of 4 AI 0.1 and the Flow Visualization and Velocity Procedure tests. A Professional Engineer shall seal test reports. Reports shall be provided to EHRS.

The average face velocity at 18 inches shall be 100 feet per minute (fpm) plus or minus 10 fpm with low flow alarms set at 80 fpm. No individual face velocity measurement shall be more than plus or minus 20% of the average flow of the hood nor shall any one measurement point be less than 80 or higher than 120 FPM.

*On/off switches for blowers are not permitted.

Directional supply air diffusers shall not discharge air toward the hood nor shall they be installed within 10 feet from the hood.

Casework under hood

A Factory Mutual approved, UL listed flammable liquids storage cabinet in compliance with NFPA 30 and OSHA regulations shall be installed under the fume hood. See Flammable Liquids Storage Cabinets Specification for guidance on storage capacity.


The hood shall be labeled with the exhaust fan number and location.

Hood Interior

Hood interior must have a flame-spread index of 25 or less.