New vision at start-up time Biological safety cabinet


New vision at start-up time Biological safety cabinet

Following recent studies done by Baker (US), a new vision was gained concerning the start-up time of biological safety cabinets (BCS).

In brief

To be sure that the workspace is particle-free, 3 steps are required:

  1. switching on the BSC with the window in working position, wait until the alarm gives “green light”;
  2. cleaning and disinfecting the workspace;
  3. wait 3 minutes until all particles and aerosols have been removed.

To clean

Product protection depends on how clean the workspace is. Removing pollution cannot be achieved due to air currents. You will therefore first have to clean the workspace with a cleaning agent.


After cleaning (removing contamination), disinfectants must be used. These procedures must be carried out according to GMP as well before as after the work is done:

  1. disinfection before work; the BSC must be switched on (in the normal working mode) so the airflow can remove all aerosols and airborne particles;
  2. disinfection after work; we advise you to leave on the cabinet until the cleaning / disinfection has been completed. By leaving the BSC on, the airflow can ensure everything is discharged. If your risk analysis shows there is no risk if you switch off the BSC (and therefore airborne particles and aerosols can come out of the workspace) you can also switch off the BSC, but this is not a common practice.

Particles of aerosols

When cleaning and disinfecting, particles will also be released in addition to aerosols. A certain amount of time is required to remove those particles and aerosols, the amount of time depends on the amount of particles and aerosols released during cleaning. It is very likely that 90 seconds after your cleaning everything has been removed, but to be sure we advise you to keep it for at least 3 minutes after cleaning.

Research Baker

The research Baker conducted on the SterilGARD® stated that the number of PPM from Helium was reduced from 73,000 to 10 PPM within 60-90 seconds. This is because the number of air cycles the cabinet needs to ‘bring in the air’ back to 0. This is why volatile disinfectants need a number of air cycles to be completely out of the workspace. The complete research contains a more detailed explanation of how the investigation took place.

We, CleanAir by Baker, have adjusted the start-up time of our EF and BioVanguard BSCs to 3 minutes after the “safe” signal from the BSC.

In practice

Normally (if we follow the manufacturer and GMP-rules) the following stages are required before commissioning:

  1. switch on the BSC and wait until all the alarms are off;
  2. clean / disinfect the workspace;
  3. wait 3 minutes so the BSC can eliminate all airborne particles and aerosols.
  4. (if desired,  disinfect before work with UV,  if present in the BSC)

End of works:

  1. clean / disinfect the workspace;
  2. Wait 3 minutes so that the BSC can remove all airborne particles and aerosols;
  3. Switch on the UV lamp (if it is present in the BSC).

“Continuation” work (this is where you can save time):

If you will not use the BSC for a longer period of time, we advise you to switch off the BSC, this saves energy. If you want to use the BSC again in a short time you can, to save start-up time, set the BSC to Standby / Night mode. Then you have to, in principle, just wait until the BSC indicates that it is safe to work in (you have already done cleaning / disinfecting and waiting for 3 minutes in the previous step).

Of course there may be circumstances for which this procedure does not apply. However, that is only based on a risk analysis only you can do. The estimatation of the risks of your work, can only done by you. With this information based on the research of Baker, we hope to be able to use working time more efficiently for the user.

Click on the link to look into the research done by Kara Held Ph.D. (Science Director Baker US).

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