• Laboratory fume hoods are important safety devices.
  • Hoods function as local exhaust ventilation that protect personnel from exposure to chemicals being handled
  • Training of personnel, proper design of experiments and careful operation of equipment are equally important for lab safety
  • Fume hoods cannot overcome poor work practices by users

Good Fume Hood Practices


  • Before using a hood check that the air is exhausting properly
  • If the hood is not working, notify EH&S, 7-2273
  • Keep sash openings to a minimum
  • Hoods are annually checked by EH&S - more frequently on request
  • Hood sash should not be positioned higher than the line on the "Approved Use" sticker.
  • If there is a need for safety/blast shields within the hood, they should be obtained separately; the sash alone should not be used as safety/blast shield.
  • Sources of emission should be kept at least 5 inches inside the plane of the sash
  • Users should keep their faces outside the plane of the hood sash
  • Keep front air foil clear - don't block with lab bench liner
  • Don't block hood exhaust openings or room air supply vents; they are essential for the proper operation and capture efficiency of the hood
  • Keep hood sashes closed when not in use
  • Design experiments NOT to exceed the hood's exhaust capacity with anticipated experimental emissions


  • Keep storage of chemicals in a hood to a minimum
    • Stored chemicals may add to the seriousness of an incident such as a fire
    • Stored chemicals block exhaust openings
  • Only necessary equipment should be placed in the hood
  • Large equipment impedes air flow and causes air turbulence and poor capture efficiency
  • Place large equipment on spacers to allow for air to pass underneath
Safety Instruction Number: 
Last Update: 
Monday, January 30, 2012