6 of the Most Common Hydrogen Peroxide Fogging Questions

Mar 25, 2020 10:14:26 AM / by The Pegasus Team

Hydrogen Peroxide Fogging is a method of decontamination that releases aerosolized hydrogen peroxide to enclosed areas like cleanrooms. The H2O2 aerosol is an antimicrobial sterilant, meaning it gets rid of things like bacteria, fungus, and viruses in areas where it is used. 

Because of its ability to work on a molecular level, hydrogen peroxide fogging is a much more efficient and effective way of eliminating microbes than manual cleaning.  Aerosolized hydrogen peroxide gets into every nook and cranny of an indoor environment, ensuring all areas are decontaminated.

Common H2O2 Fogging Questions

Now that you know what hydrogen peroxide fogging is, let’s take a look at some frequently asked questions related to this type of sanitization:

  1. Does H2O2 fogging affect the HEPA filters?
    No, this type of room sterilization does not affect the filters that blow clean air into the room.

  2. Does it matter if the HVAC unit is on or off during fogging?
    The HVAC unit should be turned off during fogging to ensure the environment is properly treated.

  3. Does the environment need to be completely isolated for fogging to be effective?
    The entire building does not need to be vacant. Only the area that is being fogged.

  4. Will fogging set off smoke and/or heat detectors?
    It is possible the fog will set off an optical smoke detector, so it is best to cover and/or bypass those detectors during fogging.

  5. When is it safe to return to the fogged environment?
    You can return to the fogged environment once the level of hydrogen peroxide in the air is down to one part per million or less. If you are air-drying the aerosol, it is safe to return the next day. If you turn the HVAC back on immediately after the fogging is finished, you can return in as little as one hour (depending on the size of the room). 

  6. Does the fog leave a residue?
    H2O2 fogging kills microbes mechanically, leaving behind no chemical residue to clean up.  Since the aerosol dissipates into water and oxygen, all that is left is an ultra-fine mist on treated surfaces that evaporates in a few minutes.  Ideally, a manual cleaning of the area prior to fogging will be performed.

H2O2 fogging is an incredibly effective method of whole-room fogging, which leads to whole-room disinfection, bio-decontamination, and room sanitization. It is easier and more thorough than manual decontamination efforts and is an excellent way to kill any unwanted lifeforms lurking in your controlled environment.


If you’d like to speak to one of our experts about fogging your critical environment, contact us today!

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