Pepper Spray
One of the most common non-lethal weapons is Pepper Spray. Used by law enforcement and soccer moms alike, it's become a popular item on keychains and in purses.
As Mark mentioned above, individual reactions to pepper spray vary. In the same way that some folks can eat "atomic" habanero peppers, etc., some folks have higher resistance to the debilitating effects of pepper spray. Resistance to pepper spray can be attributed to several factors, some of which are individually-driven, some of which are operator usage, and some which are tool-driven.
First, let's examine the stuff itself. Peppers (and pepper spray) have different "hotness" levels which are represented on the Scoville Scale. This is actually a simple and non-scientific test that measures how much dilution of a certain pepper sample is necessary before no "hotness" can be tasted. Starting at "0", where there is no dilution necessary and no hotness present, the scale proceeds to place common hot peppers from 50,000 to 200,000 SHU (Scoville Heat Units). There are a few exotic peppers that rarely reach close to one million SHU. Typical law enforcement pepper spray ranges from 1.5 to 2 million SHU, making it too "hot" to comfortably taste undiluted. The scientific flaw of the Scoville rating is that it is based upon human taste testing! There is obviously a huge potential for error.
Pepper spray's active ingredient is capsaicin. It is the capsaicin extract from a given sample that is diluted with sugar/water solution to produce the Scoville ratings. Pepper spray contains the capsaicin, propellants, and inert ingredients. Pepper sprays come in various size containers, from keychain "toys" to keg-size crowd control devices.
For the average civilian user, pepper spray has been available in four different configurations which each have strengths and weaknesses. I'll describe these in a moment. There are two different consistencies of pepper spray in common use: liquid and foam. I'll briefly outline the differences:
LIQUID: Since capsaicin has the greatest irritant effect on mucous membranes, liquid has the better penetration/infiltration qualities. It can seep upward into the nose, into the mouth and eyes and has greater potential to affect more tissue area because of this viscosity. Liquid pepper spray sometimes contains a dye marker ingredient that will temporarily identify the person sprayed to law enforcement personnel. Overall, liquid sprays are used much more frequently by police than foam.
FOAM: Foam came into popularity as a vehicle for capsaicin delivery due to a couple factors. First, it tended to "cling" to the person sprayed and would get on their hands as they attempted to wipe it off, thus allowing further distribution of the pepper in a manner similar to how one spreads poison ivy when scratching it. There have also been dye-infused foams used, in the hope that the spray would also distribute the dye. Foam, however, does not penetrate into mucous body cavities as well as liquid, so many reports state that its incapacitation abilities are not as good as liquid.
The formulation of choice is typically liquid due to these comparisons.
FOUR TYPES OF PEPPER SPRAY: there are three common variants of liquid pepper spray and the aforementioned foam.
1. Linear "stream" spray: This is a thin, fine stream that has the highest velocity leaving the canister, resulting in the longest spray range of the group. Many people are impressed by the distance figures, but forget that almost all confrontations will occur at a very close range. With the thinnest stream of the sprays, AIM is more of an issue as we attempt to hit the mucous membrane-rich area of the maxillo-facial region. Eyes are the primary target!
2. Cone "conical" spray: This pattern is exactly as described, where the stream immediately widens as it leaves the canister. Range is accordingly shorter, but hit probability increases due to coverage pattern. This is the pattern I would recommend if one has a choice. Note that this pattern is not the same with every brand, and care must be taken to avoid being surprised by how the pepper is released by your canister.
3. Fog spray: The best use for this delivery method is crowd control, where no specificity of target is sought. It basically just creates a cloud of the pepper, with range varying on container pressure and size.
4. Foam: With a relatively short range, foam is an option for those who would not choose the liquid options. I'll outline the limitations of all types below.
Before we even discuss tactical application of pepper spray, we should be aware that pepper spray carries some potential consequences to the user. First, wind may disperse some of the spray and the person using the spray may actually be hit by it too! For this reason, those in especially windy climates may prefer the "safety" of foam sprays. Even foam is not completely immune to wind dispersion. Liquid sprays may also splash off surfaces, offering a degree of cross-contamination to the user. Finally, any type of physical scuffle that occurs after spraying someone may result in some of the pepper being wiped off onto the user. For these cross-contamination reasons, anyone using pepper spray should not touch their own face after spraying, until they can thoroughly wash their hands and examine themselves. It would be "embarrassing" to blind yourself when fighting for your life!
Now, it is interesting to compare the relative "resistance" to pepper spray previously mentioned. Personally, as one who does not like hot spicy food, I think being pepper sprayed SUCKS! (Yes, we have been sprayed as part of training, so that we can understand the effects.) For some of my guys, who can eat a hot ember from the charcoal grill and grin, the effects are not as pronounced. At any rate, pepper spray does not always render a person incapable of harming you. They can still punch, kick, stab, shoot, etc. even though their eyesight is compromised. For this reason, it's best to get away as quickly as possible when you spray anyone. DO NOT STAND AROUND AND ADMIRE YOUR WORK! The most debilitating effects of pepper spray are often respiratory irritation, leaving an attacker unable to give chase. Eyesight is often affected too, such that they'll not be able to see clearly for a while. There is a small subset of subjects who exhibit very little incapacitation of any kind, but the variability of spray delivery make it difficult to assess exactly why this occurs.
By now, everyone probably wants to know HOW DO I USE IT? This is an area where we have done extensive work. We used training canisters of simulated pepper spray (exactly the same except for no capsaicin) so that we could assess how trainees would perform in field use. In an application more likely for members of this forum, the spray was carried in a pocket (or a purse for females). Since the spray had no pepper, we used cheap welding-style plastic face shields that can be found at local home improvement stores on our "bad guys". One telling drill placed the bad guy about 20 feet from the trainee, when BG would start encroaching on the trainee. Trainees, under pressure, almost universally fumbled to obtain a good grip on the canister and very rarely were able to spray the attacker as he moved in faster. Since most attacks happen at much closer range, it can be assumed that one has virtually zero chance of successful deployment of pepper spray if it is not "in hand" when needed. We then moved to dedicated carriers for the canister, many of which are similar to the waist-mounted carriers for our cell phones. Having a predictable position for the canister, as well as an unshifting orientation of the activation button, increased the odds of getting a spray off at the attacker. Depending upon the adrenal "rush" exhibited by the trainee as the bad guy rushed them, deployment and accurate use was better, but not optimal. Police deployment of their firearms against onrushing attackers follows a similar statistical pattern. (Tueller drill, for those whose Google trigger finger is itching). Finally, for those who had the spray in hand, hit results reached acceptable levels >90%. Aiming under extreme stress emphasized the reason for the conical spray pattern mentioned above.
A tactical deployment plan of "making a cloud of pepper through which the attacker must pass to get to you" has been suggested at times. Wind, and a greater chance of cross-contamination, make this a tenuous plan in my opinion.
SABRE and FOX LABS are reputable manufacturers of pepper sprays for civilian use. Our inert training units were from Fox Labs.
Caution must be used, as pepper sprays can lose their heat and can also lose their propellant strength. We were actually doing a seminar and I picked up an inert trainer canister for use and it didn't work at all. A second canister fared no better, prompting a healthy dose of laughter that also drove home an important tactical lesson: never rely solely on any "tool" to work perfectly. Have a backup plan.
I'll do my best to answer any questions about pepper spray, but there are folks far more knowledgeable than me out there. I will refer any questions beyond me to them.
Note: I just looked and pepper "gel" is being introduced as well, with properties similar to foam.
Regards
Lee