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Dimethyl benzyl ammonium chloride

Since I work in a restaurant, here's a tip. Lysol spray disinfectant and equivalents are basically the above active ingredient in a 60 percent ethanol solution. It kills viruses and bacteria. Lysol and equivalent tends to be sold out these days and isn't cheap even when available.

Restaurants and bars use tablets to dissolve in water to make a rinse or sprayable sanitizing solution. Most of them have a blue dye so you can judge the concentration just by looking at the color of the water.

There are various brands like Steramine. For six bucks you get a bottle of 100 or more tablets, each of which makes a gallon or gallon and a half of solution. The solution isn't terribly dangerous but the tablets are, so be careful. Avoid handling the tablets with bare hands.

This is not an endorsement of Katom, just an example.

Here's an example:
Awesome -- now I wonder if they are available in retail anywhere locally.
They must be. I don't think it's a restricted industrial chemical.

Well, I just checked Amazon and they have all that, including the stuff we use:

Brand means little I think. It's nice to have the colorant dye. Read the label to compare ingredients.
Most towns have restaurant supply stores, but you may get a better price on Amazon.
I’d love a jug of F-20.
You sure you don't mean MD-80 ? Lol
I’m pretty sure the sanitizer we used was F20.
Aha. Never heard of that one, but there are many.
Disposal of that stuff looks to be of some concern. It is apparently very toxic to aquatic life. Various MSDS sheets suggest little is known about bio-accumulation and persistence in the environment. The Fischer MSDS for a 50% solution (by weight) is actually very scary, but of course that's a very high concentration. Hopefully we don't find out some day that it's like some of those fluorine-based compounds.

Apparently not all formulations are as effective as an anti-viral agent. It needs to be blended with other "quaternary ammonium derivatives" to enhance its virucidal activity.

It is widely used in zillions of products though.

Wikipedia says this scary thing:

"In Russia and China, benzalkonium chloride is used as a contraceptive. Tablets are inserted vaginally, or a gel is applied, resulting in local spermicidal contraception. It's not a failsafe method, and can cause irritation."
Yeah, the stuff I use has that quaternary verbiage. Says it kills HIV. I'm not a biologist, but I seem to remember that HIV is a large and fragile virus, easily killed when outside the body. Corona viruses are much tougher. So, the HIV reference doesn't impress me. Lol. But, I could be wrong.

I've seen benzalkonium chloride many times on product labels. Looking on Wikipedia, it's used in a wide array of products for all kinds of things, including spermicides. Apparently it kills microbes but is fairly harmless to humans.
Yikes, that's an expensive product. Wish I could read the label and see what final concentration you're supposed to end up with. This is an inexpensive chemical so I can't understand the $100 price tag for 2 gallons.

The standard solution we / I use is 200 ppm. Spray it on and leave it.

I switch to Lysol aerosol only when spraying electronics like keyboards and buttons. Wall switches and everything else get the water-based stuff.
Bob's link shows a jug of 10% solution. But without added quaternary ammonium derivatives.
Is that what it is? I can't read the label. Okay, so that solution is waaaay more concentrated than what we use. A half gallon of that makes 25,000 gallons of what we spray. Lol. Sheesh.

Perhaps high concentrations are needed in cases where contact time is necessarily very short.
The good thing is that all these related chlorine / amine / ammonia compounds, even in very low concentration, "kill" or "deactivate" viruses, given a little time, like 1 to 2 minutes.

I learned this a long time ago when I was learning how to sanitize drinking water. Exposure time is key. If you're in a hurry, you have to use a lot more disinfectant. But, if you can treat the water and then let it sit for 8 hours, you can use a microscopic amount of disinfectant that's harmless and undetectable to you.
Yes, indeed! A little goes a long way!