Hypochlorous Acid and EPA N list

Prior to COVID-19 most of us didn’t give much thought to which products we were using to clean and disinfect our homes and workplace.  Since then, however, we are now more aware of what we should and shouldn’t use to be effective against the Novel Coronavirus COVID-19. Some of us have also become more sensitive to how toxic a product might be as we are all being exposed to much more than ever before.  One product that has gained a large amount of traction during this time is Hypochlorous Acid (HOCl). Interestingly, HOCl is the same substance your white blood cells produce in order to fight infections. It is a safe and non-toxic disinfectant.

The EPA N list was launched in early 2020 in reaction to the emerging COVID-19 virus. So, one might ask, why do so many of the products on the list not specifically list COVID-19 under the “virus” column? My understanding is that the Norovirus shows up more frequently on the EPA N list because it is a non-enveloped virus and is harder to kill than COVID-19 which is an enveloped virus.  Most manufacturers will therefore choose to test against the Norovirus or Adenovirus in order to achieve the listing with an “Emerging Viral Pathogen Claim”, meaning, that it will qualify as effective against future pathogens or viruses that show up from now on.  It is the strongest claim on the list.  However, when using that list to determine HOCl efficacy against COVID-19, it requires more digging and this can cause some confusion.

 Presently, it is common practice to go to the EPA N list to find out which products are effective against COVID-19.  If you search by Active Ingredient and choose “hypochlorous acid” you will find a long (and growing) list of HOCl products.  While it makes complete sense to verify that your disinfection product of choice is on the N list, it can also be confusing.  With specific reference to HOCl it is important to note that any disinfection product that has a single active ingredient of HOCl is equal to any other product with HOCl as the singular active ingredient.  The only difference between various HOCl products would be the strength, given in Parts Per Million (PPM) of sanitizer (Chlorine) regardless of if it is on the EPA N list.  The PPM can be easily measured by using a high chlorine test strip which you can find with a quick google search.

The above information would be invaluable to anyone who has decided to manufacture their own HOCl using a Hypochlorous Acid Generator.  While the solution they are producing onsite might not be specifically listed on the EPA N list, it is equal in effectivity and nature to one on the EPA N list if it has equal strength.  The HOCl product with the lowest strength as effective against COVID is listed at 170 ppm with a 10-minute kill time against the Coronavirus.

The Article,” Hypochlorous Acid – a Review” is the best article I have come across to explain HOCl, it’s uses and PPM levels and it is written by a valid authority, The National Institute of Health.  Here it is documented that HOCl at a solution strength of 200 ppm inactivates viruses including coronaviruses and decontaminates inert surfaces in less than one minute.  This article notes that HOCl has been used across a wide range of industries for quite some time including, but not limited to, healthcare (wound care & ophthalmology), dentistry, agriculture, farming and general disinfection.

If you are fogging areas with HOCl at 200 ppm, ensure that your aerosol particle size is under 20 microns as it is recommended in this article that this is an effective method of reducing viruses on surfaces.   This level of 200 ppm is important because it is at this level, and lower, that HOCl is also considered “food safe”.  Recall that the lowest PPM HOCl strength on the EPA N list is 170 ppm to be effective against COVID.  You can also google search CFR Title 40 Hypochlorous Acid and you should find the reference to the food safety solution strength (ppm).

 I stand to be corrected but am not aware of any other product that can be used for general, all purpose cleaning and disinfection across all surfaces and public areas which is simultaneously “food safe”!  This is a big deal for any entity that is responsible for cleaning publicly used areas as well as cafeterias, dining areas or kitchens.  Many schools at this point, would prefer one product for general disinfection that is food safe as many districts now have students eating at their own desks. This points to the versatility of HOCl.  Not only is it effective against COVID-19 at 200 ppm but is also non-toxic, inexpensive and food safe. When manufacturing your own, it also becomes really budget friendly at under 10 cents to the gallon.  It is no wonder some have called this the “miracle” product.

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