An Alternative Disinfectant

Many of the links on this site are “affiliate” links.  If you use the links provided to purchase the recommended items, or to navigate to the web retailer site to purchase anything at all, I may receive a small commission.  These commissions will help me expand this site and provide you with additional recommendations. As an Amazon Associate I earn from qualifying purchases.  Thank you!

Disclosure:  I am not a doctor, biologist, or chemist.  I’m just an engineer who likes to figure things out, and I’m annoyed that at the moment, one can’t readily buy typical brand name disinfectants (Lysol, Clorox) at the store.  The below article describes my investigation and solution to this problem.  Others may find it useful.  

The specific product recommended below is NOT on the official EPA list of registered disinfectants for use against Covid-19.  It will likely never be on the list because the product is marketed to gardeners, not as a general disinfectant of household surfaces, so the manufacturer will likely never request that it be on the list.  However, it contains identical active ingredients as Clorox wipes and many other products that are on the EPA list.  If any of this makes you uncomfortable, stick with common brand products on the EPA list, but good luck finding them!  Physan 20 is registered with the EPA more generally as a virucide, but not specifically for Covid-19.

After dorking it up, I recommend:

Physan 20 Broad Range Disinfectant

  • An alternative disinfection product when other options are unavailable.
  • Identical active ingredients as Clorox disinfecting wipes.  Mix it up in a spray bottle, and use it with a rag or paper towel.
  • Available!  Most people have likely never heard of it, so it hasn’t sold out (yet).
  • Cheap!  Since it’s concentrated, one 8 ounce bottle will make about 13 quarts of disinfectant after dilution to match the concentration of Clorox wipes.  At approximately $15 per bottle of concentrate, that is $1.15 per quart of diluted solution.
  • Generally safe to use after it’s diluted properly.  No harmful fumes, doesn’t irritate hands during normal use, and doesn’t harm the finish on most household surfaces.  Do not use it for skin cleansing or as a hand sanitizer.  Do not use it on items that will contact food or your mouth unless you rinse them with water after disinfecting.
  • Less packaging waste, and less resources used shipping it around the country, since it’s small and light compared to the dozens of packages of pre-moistened wipes one bottle will replace.
  • IMPORTANT:  Requires some math and proper PPE to dilute safely and properly.  It is also highly toxic to aquatic organisms, so do not pour it down the drain, even when diluted.

Physan 20 is intended for gardeners.  It is listed as an algaecide, fungicide, bactericide, and virucide.  It’s directions indicate it is intended for preventing cross contamination between sensitive plants like orchids, by disinfecting hard surfaces like garden tools, flower pots, benches, etc.  It has the identical active ingredients as Clorox wipes, but in a much higher concentration:

  • 10% N-alkyl Dimethyl Benzyl Ammonium Chloride (60% C14, 30% C16, 5% C12, 5% C18)
  • 10% N-alkyl Dimethyl Ethylbenzyl Ammonium Chloride (68% C12, 32% C14) 

Clorox wipes have the same active ingredients, but at 0.184% each.

Physan 20 must be diluted with water.  The directions and safety data sheet (SDS) give lots of strong warnings about safety hazards at its full concentration (including severe skin burns and eye damage), and I don’t intend on personally testing to see if the warnings are warranted.  It is 54 times more concentrated than Clorox wipes!  I strongly recommend wearing nitrile gloves, long sleeves, and chemical goggles while handling this product at full strength.  Once diluted, it will be just as safe as Clorox wipes.  There are no noticeable fumes or smells at any strength.

The directions for Physan 20 call for diluting it using 1 Tablespoon per gallon of water for disinfection of garden tools.  This would be significantly less concentrated than Clorox wipes.  I prefer to do a bit of math to match the concentration in Clorox wipes.

Since the two active ingredients are of the same concentration (10% each in Physan 20, 0.184% each in Clorox wipes), it’s easier for me to do the math relative to the total amount of combined active ingredients (20% total in Physan 20, 0.368% total in Clorox wipes).

To make 1 quart (32 fluid ounces) of diluted cleaner:  We want 0.368% total active ingredient.  32 fluid ounces solution * 0.00368 = 0.118 ounces of pure total active ingredient per quart of water.  Physan 20 is 20% active ingredient.  0.118 ounces / 0.2 = 0.589 ounces of Physan 20 per quart of water.  We will then convert this to a more common measurement, teaspoons.  There are 6 teaspoons per fluid ounce.  0.589 fluid ounces * 6 = 3.5 teaspoons.  

Final answer:  To make 1 quart of diluted disinfectant, mix 3.5 teaspoons of Physan 20 into 1 quart of water.  This will provide the same concentration of disinfectant as Clorox wipes.

If we used metric measurements, we could make 1 liter of solution:  

1000 mL * 0.00368 / 0.2 = 18.4 mL of Physan 20 per 1 liter of water.  

I use and recommend Physan 20 as an alternate disinfectant if you can’t find other disinfectants in the store or online.  I purchased the product with my own money, and am sharing my personal experience with the product.  

More Alternatives

There are other products that appear to be equivalent to Physan 20, with the same concentrations of identical ingredients.  I have not tried them, or inquired about their inactive ingredients.

Keep reading to Dork It Up!

A few short months ago, I would have told you that disinfectants are unnecessary for most people.  I would have recommended cleaning with basic supplies like soap or vinegar.  Now that Covid-19 has turned me into a germaphobe too, I see some usefulness in disinfecting some surfaces.  I still don’t regularly use disinfectant in my own house, since my family is socially distancing, and outside germs coming into the house are limited if we wash our hands as soon as we come in.  I do use disinfectant at the office I work at, mainly to keep my own cubicle and desk space reasonably sanitized.  Disinfectant is very useful and necessary for any shared or public places.  You could even find a tiny spray bottle and take some with you when you venture out in public, if you want to disinfect shopping cart handles and other things you need to touch.

Functional Requirements (in order of importance, for me):

  1. Effective
  2. Safe
  3. Available
  4. Affordable


There is no point in using a disinfectant unless it is effective.  But what does effective mean?

The EPA regulates sanitizers and disinfectants as antimicrobial pesticides.  They can be effective against bacteria, viruses, fungi, and/or bacterial spores.  Not all products are effective against all germs.  “Germs” is a general layman’s term for all pathogenic microorganisms, and I will use the term here for convenience.

There are actually important differences between cleaning, sanitizing, disinfecting, and sterilizing.  The below are definitions using info from the CDC and EPA.

Cleaning:  physically removing germs, dirt, and impurities from surfaces, using soap or detergent.  Cleaning doesn’t necessarily kill germs, but may.  Soaps and detergents are considered to kill viruses with lipid (fat) viral envelopes (like coronavirus), since the soap destroys the lipid layer.  Dirt can make some disinfectants less effective, so often you will need to clean before disinfecting.  

Sanitizing: should reduce the number of germs on a hard surface by 99.9% within 30 seconds.  If there are 1000 germs on a surface, there may be 1 germ left after sanitizing.  If there are 1,000,000 germs on a surface, there may be 1000 germs left after sanitizing.

Disinfecting: should reduce the number of germs on a hard surface by 99.999% after it’s designated contact time.  If there are 1000 germs on a surface, there may be 0.01 germs left (statistically) after disinfecting, so in most cases none.  If there are 1,000,000 germs on a surface, there may be 10 germs left after disinfecting.  If there are 1,000,000,000 germs on a surface, there may be 10,000 left after disinfecting.

Sterilizing:  a process that destroys or eliminates all forms of microbial life.  This can be accomplished by heat (dry or steam), or particularly strong chemicals such as ethylene oxide gas.  This is what is done to medical needles, surgical instruments, and internal medical devices before packaging or use.  Sterilization is not something typically performed on everyday objects or surfaces, as there isn’t much point in doing so.  As soon as a sterile object is touched by a non-sterile hand or object, it is no longer sterile.

Contact Time

One can only be confident that a disinfectant or sanitizer will fully work if the hard surface is visibly wet for the entire designated contact time.  Contact times can vary considerably, from 10 seconds to 10 minutes, based on the product or active ingredient, if you are disinfecting or sanitizing, or the germs you are trying to kill.  You will need to read the directions on any product.

I don’t know who could ever have the patience to comply with a 10 minute contact time.  Here in dry Colorado, nothing stays wet for 10 minutes, so you would have to re-apply disinfectant every 30 seconds for 10 minutes, or basically immerse the thing you want cleaned in a puddle of disinfectant.   Shorter contact times are much better for real world use.  

Thankfully, if you don’t wait the full contact time, while you may not have fully disinfected a surface (killing 99.999% of germs), you may have at least sanitized it (killing 99.9% of germs).

While many product instructions don’t mention it, contact time varies depending on what germ you are trying to kill.  Viruses and bacteria are destroyed with different biological mechanisms, and some are more resistant to destruction than others.  Most packaging will provide a single, clear contact time for ease of use and understanding, and this contact time will typically be conservative, meaning it will likely kill all germs in that time.  

Some (but not all) packages of Clorox wipes give more detail.  See the image below.  These directions indicate a 4 minute general disinfection contact time, but a 15 second contact time for virus disinfection.  They also provide a seperate 10 second general sanitizing contact time.  If you are in a hurry and only give a surface a quick wipe, you are still doing some level of sanitizing and/or disinfecting, especially if you are mainly concerned with viruses.  It is interesting that the front of the package of Clorox wipes says it kills 99.9% of viruses and bacteria (consistent with a sanitizer), and not 99.999% (consistent with a disinfectant).  Perhaps they know people never actually achieve the 4 minute contact time to fully disinfect.

Looking through the EPA list of registered disinfectants for Covid-19, I observed that many products with the same active ingredients have wildly different contact times.  I suspect that concentration has a lot to do with this.  The contact time stated on the Physan 20 directions is 10 minutes, but this is using a much weaker solution than Clorox wipes, which have a 4 minute contact time.  I do not recommend arbitrarily choosing a higher concentration of Physan 20 (more concentrated than Clorox wipes) in the hopes of further reducing the contact time.  It may not work (the relationship between time and disinfection may not be linear), and you may also harm yourself with unnecessarily strong chemicals.  Since Clorox chooses to not make their wipes stronger, I imagine that they consider higher concentrations not beneficial and/or less safe.  

How Many Germs Does it Take to Get You Sick?

Thankfully, a single virion (virus particle), bacteria cell, or fungus spore will not typically get you sick.   It depends on the microorganism and the strength of the person’s immune system, but an infectious dose may be anywhere from 1 (an estimate for ebola), 10 (a low estimate for norovirus), 1000 (a low estimate for the flu), to more than 1,000,000,000 (an estimate for salmonella) germs.  A person with a compromised immune system may get sick from a smaller dose.  Experts sometimes quantify the infectious dose by its ID50, the infectious dose to infect 50% of a susceptible population.

The infectious dose also likely affects the severity of illness if you do get sick, and perhaps also the incubation time.  Get a huge dose of the flu from a sick person sneezing directly in your face?  You might get a more severe flu than if you picked up a few virus particles from a doorknob that a sick person touched 6 hours ago.  One sneeze may contain millions of virus particles!  The bigger dose of germs you get, the less your immune system can resist it.

The infectious dose of Covid-19 is not yet known.

Storage and Expiration

Disinfectants need to remain effective under normal storage conditions (a cool, dark, and dry place), and not expire in a short period of time.  I need to be able to just keep the disinfectant with my other cleaners, and be able to assume that months or even years later that it still works.


If a person is going to use a disinfectant around their home or place of business regularly, it needs to be safe.  Specifically, I have the following expectations on a product used in this manner:

  • No PPE required at normal concentrations (after dilution if needed).
  • Does not severely irritate skin on your hands if you forget to wash them after cleaning.
  • Does not harm people or pets inadvertently coming into contact with surfaces or objects that have been recently cleaned.  This includes kids or pets occasionally licking or putting objects in their mouths, or adults touching an object and then touching their faces or eating without first washing their hands.
  • Does not emit harmful or irritating fumes.  Preferably doesn’t smell at all.  
  • Does not harm the surface or object I want to clean.

Basically, I don’t want a disinfectant I have to treat like a severely hazardous chemical.  However, I am OK with some common sense being required:

  • Do not drink it.  
  • Keep the bottle of disinfectant away from kids and pets.  
  • Do not use it in a way that is obviously incorrect, like cleaning skin with it, or using it on objects that will regularly come into contact with food and/or mouths (dishes or utensils) without rinsing off the residue afterwards.

I am OK with needing to treat a concentrate with a bit more care.  A quart of solution will last me many months, so I won’t have to bust out the PPE too often to make more.  I can keep the concentrate REALLY out of reach of kids and pets.


Under normal circumstances, cleaning products are readily available.  However, we are currently living in circumstances that are far from normal!  As of early May 2020, most stores (physical and online) are out of stock of all commonly used disinfectants.  I’m not going to drive around to lots of stores checking for stock all the time, exposing myself more to potentially sick individuals.


I’m willing to spend a couple bucks on products to protect myself and my family, but it has to be reasonable.


There are several common chemical compounds that are effective in killing bacteria and viruses, but they all have their pros and cons.


Alcohol is effective against SOME viruses if you can find it in a high enough concentration.  Alcohol is effective against viruses with a lipid (fat) viral envelope (influenza, coronavirus) but not viruses without this lipid layer (norovirus).  A solution must be at least 60% alcohol to be effective on viruses.  Concentrations that are very high (~90%) are actually less effective on some bacteria, as water is needed to effectively denature proteins, but high concentrations work fine on viruses.  If you can only find 90% alcohol, dilute it with some water for better effectiveness on bacteria.  Do some math so you don’t dilute it too much.

Information sources provide a range of contact times for contact time for alcohol.  This source indicates alcohol will kill coronavirus in 30 seconds.  From what I have read, for germs alcohol works on, it works quickly, which is good because alcohol evaporates very rapidly.  You won’t be able to keep things wet with alcohol for more than 30 seconds without repeat application.

Interestingly, the FDA has NOT approved any disinfectant with only alcohol as the active ingredient, likely because it’s not universally effective.  You will not find any alcohol based products on the official covid-19 list of disinfectants unless there are other approved active ingredients in the product.

Alcohol is generally safe to use.  It can dry out your skin after repeated exposures.  It gives off some fumes that are slightly irritating.  It can damage household surfaces, like some plastics or the finish on some wood furniture.  It is highly flammable in high concentrations, and it burns with an extra dangerous clear flame you can’t see.

Ethyl alcohol (ethanol) is the consumable type of alcohol found in alcoholic drinks.  Typical liquor is 80 proof (40% alcohol), and is not strong enough.  You may be able to find “grain alcohol” (one brand name is Everclear) in your local liquor store, but it is illegal in 14 states (New Hampshire, Nevada, California, Ohio, Florida, Maine, Maryland, Massachusetts, Michigan, Hawaii, Iowa, Minnesota and North Carolina).  Everclear comes in 151 proof (75.5% alcohol) and 190 proof (95% alcohol).  Buying disinfectant at the liquor store is rather expensive, since liquor is marked up and taxed heavily.  Expect to pay $15 or $20 for a 750mL bottle.

Hardware stores sell “denatured” alcohol, which is typically a mix of ethanol and methyl alcohol (methanol).  When it comes to alcohol, “denature” means to make it unfit for drinking by adding toxic substances.  Methanol is poisonous, so humans can’t drink it.  (The government wants you to pay tax on drinkable ethanol, so this cheap stuff can’t be drinkable by law!)  Sometimes other extra nasty sounding denaturing ingredients can be added also, like methyl isobutyl ketone.  Not only is methanol not as effective a disinfectant, other denaturing ingredients can make this stuff stinky and hazardous to be around.  Avoid denatured alcohol!

Isopropyl alcohol is the stuff sold at many stores in the first aid section, typically in 70% or 90% solutions.  It is also poisonous (don’t drink it), but doesn’t have other nasty things in it, and is generally safe to use.  It is very cheap, at a few dollars per liter.  As of May 2020, it is difficult to actually find in any stores to buy it.  

Isopropyl alcohol is a pretty good choice for disinfection if you can find it. 


Bleach is effective at killing just about all microorganisms, is cheap, and readily available in the laundry supplies section of just about any store.  The word bleach might suggest different things, but in this case it means chlorine bleach, or by its chemical name, sodium hypochlorite.  “Color safe” bleach is not really bleach!  

Bleach from the store is very concentrated and hazardous.  It must be diluted with water for typical cleaning, sanitizing, and disinfecting.  Recommendations for the concentration of bleach required for disinfection is all over the place.  Further complicating things, bleach you buy in the store is not all the same!  Some are more concentrated than others, ranging from 5 to 8%.

The CDC recommends diluting bleach by adding 4 teaspoons per quart of water, but doesn’t say what concentration they are assuming you are using.  They say aim for a diluted concentration of 1000 ppm (0.1%), so doing the math, they are assuming you are using 4.8% bleach from the store, which is on the low side of what is typically available.  

The bottle of bleach I happen to have is generic “concentrated bleach” from Target.  It is 5.7% strength, and the bottle recommends 9 teaspoons per quart of water for disinfecting, which would provide a 2800 ppm (0.28%) solution, or nearly 3 times the concentration that the CDC recommends.  Maybe the manufacturer wants you to use a lot of their product!

A local health department in Colorado gives similar recommendations for strong concentrations of bleach for disinfection, but also a recommendation for a much weaker solution for sanitizing (¼ to ½ teaspoon of 8% bleach per quart of water, or 50 to 200 ppm (0.005% to 0.02%)).

Recommended contact times for bleach are also all over the place.  The CDC typically recommends 10 minutes, which is impractical.  This is their recommendation for general disinfection, when you don’t know what you are dealing with.  Basically 10 minutes will kill anything.  This more focused recommendation from the CDC specific to covid-19 lists a 1 minute contact time.  

Bleach loses effectiveness over time.  The chemical sodium hypochlorite breaks down into salt (sodium chloride) and water.  Clorox says it should last a year in the original bottle, but then will start to degrade faster.  Bleach bottles list the manufacturing date, not the expiration date, and the date provided is cryptic.  Somewhere in the code printed on the bottle, it contains the last two digits of the year, and the day of the year.  The bottle I have says “20 055”, meaning it was made on the 55th day of 2020, or February 24, 2020.  I have read in many sources that diluted bleach breaks down much faster than concentrated bleach, but I haven’t found a good explanation of the chemistry and why that is true.  Some recommendations say to use your diluted bleach solution within 24 hours, but this one from Clorox implies you have a bit more time.

Bleach is quite hazardous in concentrated form, and still somewhat in diluted form.  Bleach can damage skin and eyes, and gives off irritating fumes, even when diluted.  It stinks!  Cleaning with bleach with little ventilation is highly unpleasant.  

Bleach is highly damaging to various materials.  Many metals, even corrosion resistant stainless steel and aluminum, will corrode and pit if you leave bleach on them for long.  Bleach can harm some plastics like polyester.  It can be difficult to find a spray bottle that won’t be destroyed over time by the bleach you put in it.

DANGER:  If bleach is mixed with any other cleaning product containing ammonia or vinegar (and potentially other chemicals too), a chemical reaction will occur that releases poisonous chlorine gas.  Do not mix bleach with anything other than water.

If bleach is all you can find and you need a disinfectant, go for it, but it is not my first choice.  It stinks, harms materials, and loses its effectiveness quickly after you dilute it.  It might be the best choice, however, for non-enveloped viruses like norovirus.

Quaternary Ammonium Compounds

Many commercial disinfectant products (Clorox wipes, Lysol spray, etc.) use chemicals called quaternary ammonium compounds.  These chemicals are sometimes referred to as “quaternaries” or “quats”.  These compounds are a group of similar chemicals that have long, similar, but different chemical names.  Here are a few:

  • alkyl dimethyl benzyl ammonium chloride (Clorox Wipes)
  • alkyl Dimethyl Ethylbenzyl Ammonium Chloride (Clorox Wipes)
  • Dimethyl Benzyl Ammonium Saccharinate (Lysol Spray)
  • alkyl didecyl dimethyl ammonium chloride
  • dialkyl dimethyl ammonium chloride
  • didecyl dimethyl ammonium bromide
  • dioctyl dimethyl ammonium bromide

Sometimes instead of “alkyl”, “n-alkyl” will be used in the chemical  name.  The “n” refers to a carbon chain of varying lengths, which is why even longer versions of the chemical names list different carbon chain lengths like C12 and C14.

Quats have been shown to be effective fungicides, bactericides, and virucides (for enveloped viruses), but less effective against spores and nonenveloped viruses.

Contact time varies depending on the product.  Lysol spray lists a contact time of 3 minutes for general disinfecting, but a 10 minute contact time for norovirus (a non-enveloped virus).  Lysol also lists a 10 second contact time for sanitizing.  Clorox wipes list a contact time of 4 minutes for general disinfection, but a 15 second contact time for virus disinfection, with a footnote that this applies specifically to the flu virus and coronavirus.  Clorox wipes also provide a seperate 10 second contact time for sanitizing.  Some product packaging has less detail and only provides a single, conservative contact time, such as 4 minutes, to make this less bewildering.  My takeaway is that even a quick spray or wipe is probably fine for covid-19, and does at least some good (santizes) for bacteria.  Use enough liquid that the item stays wet for a bit.  If you want to really make sure you kill everything, spray and wipe several times until you hit that 3 or 4 minute contact time.

Products containing quats are generally safe to use, and generally safe for most surfaces you want to clean.  This is likely the reason that these chemicals are popular disinfectants.  However, like many chemicals, quaternary compounds are not so inert that you can use them recklessly.  Don’t ingest them, don’t use them on things that will be in regular contact with mouths (unless rinsed with water after disinfecting), don’t use them as baby wipes.  Don’t go crazy disinfecting everything all the time, just use them when prudent.  Just regular cleaning is still fine for most things, especially in a typical home.

Quats in low concentrations can sometimes cause mild skin or respiratory irritation.  I’ve never personally noticed any issues, but some people are likely more sensitive than others, and some people may be allergic and have severe reactions.  In high concentrations, the health risks can be more severe, so use caution with any concentrated product.  Studies have shown that quats cause birth defects and fertility problems in lab mice.  Quats are toxic to aquatic life, so careful disposal is needed (don’t dump extra cleaner down the drain).

Products that contain quats typically contain other ingredients too.  These ingredients may have their own concerns with safety and/or appropriateness for cleaning certain surfaces.  These ingredients are typically added to provide additional cleaning power.  The inactive ingredients are often not listed on the packaging, but Clorox provides a list of them online.  Clorox wipes contain 3 different alcohols, baking soda, and citric acid, all of which will provide some degreasing and cleaning properties.  The concentration of alcohols is likely not enough to add significantly to their antimicrobial properties (the wipes don’t give off an alcohol-like smell, so there can’t be much).  Most of the liquid in each wipe is likely water.  Clorox does not provide the amount of each ingredient, but the ingredients on the list appear to be sorted by % of the total of all ingredients (water is first).  

Consumer-oriented disinfecting products containing quats are rather hard to find in stores or online at the moment.  However, lots of less consumer-oriented products are still available.  The trick is figuring out which ones might still be appropriate for general cleaning.

There are several different quaternary compounds, and many products use them in different concentrations.   It is difficult to compare one versus another, unless they happen to contain identical active ingredients.  The different quaternary compounds may have different minimum effective concentrations, and different minimum contact times, so guessing at either may result in the product not working properly.

Here are a few I found:

  • Physan 20:  Marketed to gardeners, to disinfect garden tools and surfaces to prevent cross contamination of sensitive plants, like orchids.  Identical active ingredients to Clorox wipes.  20% concentration of total active ingredients, requires dilution to match the 0.368% total active ingredients of Clorox wipes.  See my instructions above.  The inactive ingredients are not listed, so I sent an email to the manufacturer.  They informed me that the remainder of the product is mainly water, with trace amounts of ethanol.  Therefore, Physan 20 will not provide any cleaning power, as it does not contain degreasers like Clorox wipes.  I dilute Physan 20 to match the concentration of Clorox wipes, and then follow the contact time indicated for Clorox wipes (4 minutes general disinfection, 15 seconds virus disinfection, 10 seconds general sanitizing).
  • SA-20 Southern Ag Disinfectant:  Also marketed to gardeners, same active ingredients as Physan 20.  The inactive ingredients are not listed.
  • Control II Concentrate disinfectant:  Marketed for disinfecting of medical equipment.  Same active ingredients as Physan 20.  The inactive ingredients are not listed.  Seems to be scented.
  • Nu-Foam Sanitizing Tablets:  Marketed to restaurants and other businesses as a sanitizer (not as a disinfectant) for dishes and other food contact surfaces.  Hopefully restaurants rinse the dishes again with water after sanitizing them.  The product consists of little tablets that dissolve in water.  Contains alkyl dimethyl benzyl ammonium chloride dihydrate (not the same as Clorox wipes or Lysol).  It is unclear if it can be made more concentrated to be a disinfectant, or if it is safe at higher concentrations..
  • Steramine Quaternary Sanitizing Tablets:  Appear to be identical to Nu-Foam.

Products containing quaternary ammonium compounds are good choices for safe and effective general disinfection, although they may not work on non-enveloped viruses like norovirus.  Most consumer products are unavailable, but less consumer-oriented products can be found.  

Safer and/or More Environmentally Friendly Options

Most chemicals have some hazards if used or disposed of inappropriately.  Some chemicals are more inherently safe than others.

The EPA has a special program called Design for the Environment, or DfE.  Manufactures of antimicrobial pesticide products can apply to be certified to use the DfE logo.  Approved products are effective and less likely to be hazardous or bad for the health of humans or the environment. 

Products containing one or more of the following ingredients may be considered for the DfE logo:  citric acid, hydrogen peroxide, L-lactic acid, ethanol, isopropanol, peroxyacetic acid, and sodium bisulfate.

Green Seal has a list of products that are on the DfE list.  Most of these products either have a long contact time, are more industrial oriented (i.e. commercial janitorial products), or are far more powerful cleaners than should be used for general disinfection.  For example, I wouldn’t recommend Lysol Power Bathroom Cleaner for disinfection of your computer mouse.  It has strong ingredients that foam and remove soap scum and lime scale.  It’s probably more hazardous to your skin and eyes than regular Lysol disinfecting spray.  Just because the active ingredient is “safer”, doesn’t mean the total product is safer or better for every intended use!  The Lysol product may be safer than other bathroom cleaners?


I use and recommend Physan 20 as an alternative disinfection product when other options are unavailable.  I paid for it with my own money, and am sharing my personal experience with the product.

Many of the links on this site are “affiliate” links.  If you use the links provided to purchase the recommended items, or to navigate to the web retailer site to purchase anything at all, I may receive a small commission.  These commissions will help me expand this site and provide you with additional recommendations. As an Amazon Associate I earn from qualifying purchases.  Thank you!

Dork It Up Yourself:

If you are not an expert in a field, you need quality references to figure things out.  I prefer very detailed references written by experts in a way that non-experts can comprehend them. The below links provide some useful info.

CDC definition of terms like disinfection and sterilization:

Very detailed EPA guidance on cleaning, sterilization and disinfecting:

Detailed info on the effectiveness of different chemical disinfectants on different germs:

Ethylene oxide gas sterilization:

Antimicrobial products that qualify for a Design for the Environment Logo:

Infectious Doses:

Expert discussion of Covid-19 and infectious doses:

More expert discussion of infectious doses:

Even more expert discussion of infectious doses:

Alcohol contact time:

CDC Bleach Dilution Instructions

Info on quats:

More info on quats:

Sanitizing vs disinfecting:–14213

1 thought on “An Alternative Disinfectant”

  1. Thanks, Ben. You’ve obviously done a LOT of research on this. I’ve been going with the isopropyl alcohol, slightly diluted with water (aiming for 50% concentration), and a bit of Dawn. It’s nice to have other options, as well as more specific measurements.


Leave a Comment