Fume hoods

Definition:

  • The fume hood is one of the most important laboratory equipment items and ensures that we can work with hazardous substances without being exposed.
  • Apart from ventilation, the fume hood has connections for electricity, cooling water, vacuum, and gases.

Function:

  • A properly used fume hood provides efficient process ventilation and protects against exposure and ensures that solvent vapor does not reach explosive concentrations.
  • The hood also serves as additional protection against splashes and fragments from unwanted reactions.
  • Flow rates:
    Stand-by with hood down: min. 0.50 m/s
    Normal operation: min. 0.50 m/s
    Hood max open: min. 0.50 m/s
    Forced operation is used in case of accidents, and will open for maximum suction regardless of hood position - forced operation will trigger the alarm.
  • In order to save energy, the ventilation in the laboratories will be shut down during holidays in building 1513 (2nd and 3rd floor).
  • If you have to use the ventilation in the teaching laboratories during closing periods, you'll find buttons for ”extended operation” in the hallways.
  • Ventilation in research laboratories and in all storage cabinets for chemicals is running constantly.

Application:

  • When you are to use a fume hood, always start with a user check in order to ensure that the hood is functioning correctly.
  • The most important thing is that the green lamp is lit up and that the fume hood reacts correctly when you open the hood. 
  • The control ledger attached to the fume hood contains instructions for using the fume hood correctly. 
  • When you leave the fume hood, please ensure that you have lowered the hood, put lids loosely on refuse cans, and that you have shut off as much as possible.

FAQ/Typical errors:

  • The fume hood is raised too high and the sound/light alarm starts. This means that suction is not sufficient, and you will be exposed to the setup you are working with. Please note that the suction is NOT increased by shutting down the alarm! Instead, you must lower the hood!
  • If the fume hood is filled with too much, the air flow will be poor.
  • The air foil ”wing” at the front of the fume hood table ensures proper flow. This must remain in place during use.
  • Latest-model fume hoods will automatically decrease suction and lower the hood, if no activity is detected in front of the fume hood.
  • The fume hood must be turned off completely (the green button).
  • If the fume hood has been turned off, it can be switched on again with the green button.
  • The hood won't close!!! 
    Check if anything is obstructing the hood.

In case of operational problems:

  • Send an e-mail to the operations staff at stbyg2service@au.dk or call the contact persons
  • Put a sign with ”Defect” on the fume hood and report the failure immediately.
  • Using a defect fume hood is not allowed.
  • NOTE: If the hood won't close: Check for obstructions under the hood plate!

Contact:

Allan Madsen - mobile 2899 2015