Decontamination Using Dry Foggers, Q&A

  • If we decontaminate an area including corridors and rooms, which can be fully isolated, but is larger than 287 m3 ( each room is about 40m3), can we guarantee accepted levels of sanitization with multiple cycles?
    • You would refill and restart as needed, until area sanitize is complete. The efficacy of the sterilant used will control how effective the decontamination is against spores, molds, fungus, viruses, etc. The CRF4-S, CRF2-S, DF2S and our new DF4S are dry fogger tools, which are used by human beings, and the dry fogger performance achieved is controlled by your technicians to disperse your desired sterilant.
  • Can you guarantee that fog will reach all areas to be disinfected?
    • We can not guarantee what your team is accomplishing. We can say that if you are sanitizing an enclosed area and you have the right supporting equipment (at least two assisting flow fans + 5 humidity sensors) for the right volumetric area; then you can achieve 50 to 70% sanitizing humidity, using the correct dry fogger. For example, a small dry fogger could not achieve a sanitizing / decontamination goal for large area requirements. Once you feel your area is adequately sanitized, based on the humidity level achieved, you would turn the DryFogger off, allowing the sterilant fog to contact the air and all direct surfaces for at least 15 minutes, then evacuate the sterile air, and replace with good air.
  • Hydrogen Peroxide is a chemical typically accepted/approved by the EPA. A log 6 reduction of pathogens is only linked to the chemical type or it is also linked to the concentration of the chemical in the fogging solution?
    • This is correct. The efficacy of H2O2, depends on the % of concentration in purified water such as distilled water, deionized water, etc. For example, 7% H2O2 in DI water would be too low for a high kill rate of viruses, molds, spores, etc. 30 – 40% H2O2 in DI water is better % for a high percentage kill rate of bio-organic spores, molds, yeasts and viruses such as conora virus and COVID-19.
  • What concentration of the chemical is required to achieve a log 6 reduction of pathogens? Is it 35% solution? In your site you mention a range of 3.5-35% solution in distilled/purified water.
    • When trying to assign a log scale to killing a virus, it is not a good way to describe. For example, if you were to use a 7% mixture of Minncare (Paracetic acid + H2O2) in Distilled water, the resultant kill efficiency is a typical 99.95% of bio-organics including molds, spores, yeasts, coronavirus, etc. H2O2 by itself is not as effective as Minncare, but some people prefer H2O2, (hydrogen peroxide). 7% H2O2 would be OK for low level sanitizing of an area, but you referenced 6 log, which is very hard to achieve in normal human environments. See #3 above. Thus, when using only H2O2, your H2O2 concentration in DI water must be higher to achieve a high kill rate of unwanted bio-organics.
  • Application of the CRF4-S fogging method requires no air after treatment, so by the time fogging is completed, we need some dissipation time to complete disinfection, but no ventilation? What do the 45 minutes of operation cycle include?
    • 45 minutes is simply the typical operating cycle of a full CRF4-S. After sanitizing the area, you would typically want a minimum of 15 minutes contact time before replacing the sanitized air. And you would typically replace the air 3 times after sanitizing. So, if you were sanitizing an enclosed 250 cubic meters; after reaching between 50% and 70% humidity in that area, let the sterilant contact for 15 minutes. Then open area to fresh air access and replace 750 cubic meters of fresh air into the 250 cubic meter space.
  • This model has the option of being remotely operated, but is there an option of storing any information regarding the times and duration of the cycles repeated?
    • The CRF2-S, CRF4-S and DF2S do not have data storage. Data storage is included on our larger DF4S DryFogger system designed for 300,000 cubic feet (8500 cubic meters) to 3 million cubic feet per cycle.
  • Are there any option for renting a dry fogger for display/testing purposes?
    • No. Due to the elevated demand for decontamination foggers in these times, we are unable to provide rental units.
  • How do the 4 Dry Foggers you offer compare in performance?
    • The CRF2-S is a basic, low cost, DryFogger with a constant sterilant fog output and no flow controls, which is used for volumetric requirements of 3,000 cubic feet or less.
    • The CRF4-S DryFogger provides adjustable control of sterilant fog airflow velocity, fog volume and wireless control, and is used for volumetric requirements of 10,000 cubic feet or less in small businesses, hospitals, pharmaceutical companies, etc.
    • The DF2S DryFogger has a constant sterilant fog output, which is used for volumetric requirements of 35,000 cubic feet or less in businesses, hospitals, pharmaceutical sterile rooms, etc.
    • The DF4S DryFogger has an adjustable control of sterilant fog airflow velocity, sterilant fog volume, includes data logging and total wireless control, which is used in volumetric areas from 300,000 cubic feet to 3 million cubic feet in large conference centers, indoor sports arenas, manufacturing companies, etc.
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