On Her Own

Choosing pepper spray: technical details

It’s no secret that I’m a huge fan of pepper spray, and recommend it often. The modifier that’s often overlooked or misunderstood, though, is “quality.” While bear spray is heavily regulated in the United States, human spray surprisingly is not. It’s not only an industry without enforced standards, it’s one that’s full of white label product that is branded and rebranded for anyone who wants to say that they sell a self-defense product. That leads to a lot of pepper spray on the market that doesn’t work very well, which is part of its “ineffective tool” reputation in some circles. Pepper spray can work well, however, so let’s talk about choosing a high quality formula and packaging that you can stake your life and safety on. This is going to get a bit technical and full of acronyms, but stick with me – you can understand this!

Pepper spray is a combination of the spicy stuff in hot peppers – oleoresin capsicum (hence “OC spray”), a solvent in which that spicy stuff is dissolved, and a propellant to help shoot all of it out of the can you carry it around in.

OC is the active ingredient and the one you should be most concerned with when selecting the pepper spray you will rely on. Its heat is measured in two ways: Scoville heat units (SHU), or major capsaicinoid content (MCC). Most pepper spray will claim somewhere between 500,000 and 2 million SHU, compared to jalapeño peppers, which are generally around 3,000 to 8,000 SHU. That would seem pretty hot, but SHU are historically determined by what is essentially a taste test and is relatively subjective. If a pepper spray only advertises its SHU, it’s behind the times because we have a better way now in MCC.

MCC is a lab-tested value that measures the concentration of the active ingredient in the spray, the part that actually does the work. You’re looking for somewhere between 0.7% and 2.0% MCC. Local law may dictate lower, but usually not below 0.7%, and most of what you will find on the market right now is 1.33%. Higher isn’t always better here, by the way. Bear spray maxes at 2.0% by federal law; you don’t need more for humans. Anything in that 0.7% to 2.0% range will work just fine to get the optimum effect out of quality pepper spray. If the pepper spray you are looking at doesn’t disclose MCC, it may not have been tested and you might not get consistent results when using it.

The next piece of the pepper spray puzzle is the solvent. Since raw OC is a powder, it needs to be suspended into a liquid so that you can direct it to a target. In most cases, you won’t be able to find out the exact composition of the solvent used in the pepper spray you are looking at unless you look at the Safety Data Sheet (SDS), but the important part to know is that it needs to evaporate for the OC to take effect. Isopropyl alcohol therefore has the fastest effect, but you’re probably not going to find it anymore because it’s flammable. Instead, most pepper spray uses water as its solvent or solvent base now, which still evaporates quickly and easily and is “taser safe” for law enforcement purposes. The exceptions are the gel- and foam-type products, which are intended to minimize how much OC ends up not on the target, at the cost of far slower evaporation. I don’t recommend most gels and foams outside of very specific contexts because of that time it takes to begin working.

Finally, propellant is the part of pepper spray that gets the OC and solvent to where you want it to go. The propellant and the pressurized canister that the pepper spray is packaged in combine to ensure that the spray reaches to a consistent distance and with a consistent pattern. The canister will have an effect on whether the OC can settle out of the solvent, and whether the unit will spray at different angles or upside down. Again, you may not be able to easily find out exactly what a specific manufacturer uses, though most use nitrogen or perhaps carbon dioxide as the propellant and similar canisters are manufactured by a small number of companies. If you want to geek out, locate or ask for the SDS, which will tell you exactly what is in the pepper spray you’re looking at, but perhaps in more detail than is useful to you. From a consumer perspective, focus primarily on MCC percentage and solvent formulation (some form of liquid spray versus gel or foam).

In addition to what’s actually in the pepper spray you’re considering, you should also check to see if it has a manufacturing or expiration date printed on it somewhere. It may be small or difficult to find, but it should be there. If not, then you should strongly consider selecting another brand. Knowing how old the particular can of pepper spray you have in hand is important because propellant can leak out, even if stored properly. With insufficient propellant, your pepper spray won’t spray as far as you expect. You can imagine how that might be a problem in the face of an attack, so insist on that detail, then make sure you store extra units in a temperature-stable environment, preferably at regular room temp. You should replace your pepper spray every few years at a minimum, even if you don’t use it, counting from the manufacture date and not when you bought it or started carrying it.

Also consider the way in which the canister you are looking at operates. All of them have some sort of mechanism to prevent you from accidentally activating the spray. The twist-and-press variety tends to more easily turn itself to “on” as the unit sits in a pocket or bag and gets knocked around. My preferred alternative is the type that has a hard cover held in place by a spring over the spray button. You slide your thumb under the cover to use the unit. It takes a little less fumbling to get it right, and unintentional pepper spraying happens less often. While a particular type of safety doesn’t necessarily indicate that a pepper spray is high or low quality, it’s still part of the product formulation and packaging you should be thinking about.

For more info about pepper spray, including why it’s a good choice for personal protection and how to use it properly, be sure to check out the Pepper Spray playlist under the Videos tab on my page. For the pepper spray I personally use and recommend (and get a cut of), grab the On Her Own collaboration pack from POM. Or take everything you’ve learned from today’s post and find your own quality pepper spray.

Hi, I'm Annette.

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