OC (Pepper) spray is a good tool. At chemical munitions instructor school we were taught that CN & CS Tear Gas works on humans, but won't work on K9's due to them not having Olfactory Glands (Tear Ducts). From personal experience, OC Pepper spray does work on K9's, cats (Before all you cat lovers get upset, the cat was in the closet when we sprayed the bad guy with a pepper fogger so it also got a dose), bears, and other 4 legged critters very well. CN & CS Tear Gas is an irritant, that will make your eyes tear, sinus's open up and snot run, and CS makes my skin burn and feel like its get millions of needles sticking in it. If you put CN or CS into a place, people that are effected by it will want to get away, their eyes are watery but they can still see enough to find their way out of where they are at if they so desire, that is why in SWAT we put it into structures, and oftentimes it is used for unruly crowds, etc. OC is ground up pepper (a food product that you can spray on your Taco Bell), that when introduced to your eyes, will dry the eyes out due to the heat, and the eyes will involuntarily swell shut to maintain the moisture, and when inhaled into the mouth and nose will cause a burning sensation that makes it feel like you can't breath (but you can, as it doesn't effect breathing), and it also causes a burning sensation on any skin that it gets on.
OC sprays come in 3 basic forms, fogger, stream, and foam. The fogger unit is a miniature fire extinguisher of sorts, where a small 3-oz or 4-0z can can empty itself in just a couple of seconds, dispersing a large cloud of OC particles (kind of like a very fine talcum powder) in the are of what you want to spray, so its kind of hard to miss. The fogger units are nasty to be hit with, as the fine powder gets effects on the eyes quickly making them swell shut, gets into the nose and mouth causing the burning sensation where you think its hard to breath, and the powder stays with the bad guy for a time as when we have taken bad guys to jail the OC powder comes off of them in booking and gets into the air system for hours (Staff & inmates on numerous floors will complain). A negative to the fogger is that it empties the can very quickly, and has a high contamination rate of effecting the person doing the spraying, and anyone else around them, as the fog is very effected by wind and has a long air hang time of about 20-minutes from experience.
Stream units spray like squirt gun in a sense, and most units will generally reach out further in distance than fogger for foam units. A stream unit in the 3-oz or 4-oz size will generally give 30-sec to 1-minute of spray. The stream units are generally wet, as the OC particles are carried in liquid (like water) stream, and the stream will break up into smaller particles the further it reaches out. The stream needs to be sprayed directly into the eyes for best effects, and generally takes about 30-seconds to 1-minute or more for the eyes to involuntarily swell shut, though some people give up instantly. The stream units can still cause contamination to the user and others in the area, but has a lot less contamination as compared to the fogger.
OC Foam units basically spray out a liquid, that foams up like shaving cream in a sense the further it gets from the spray can. From my experience it doesn't go as far as a regular stream unit, and is more effected in a stiff cross wind (couldn't hit a mean dog that had me cornered at 7' in a 30-mph cross wind). Foam units are like the stream units, as a 3-oz to 4-oz unit will give 30-sec to 1-min of spray. The times I have been sprayed with the foam directly in the eyes, it will swell my eyes shut instantly, as compared to the stream that takes about 1-min on me, and fogger was instantly. The foam doesn't give me the burning effects in the nose & mouth, but it will swell my eyes shut for about 30-min.
The nice thing about OC spray is that it does work on both humans and critters like dogs. It is easy to carry, light weight, and small. It is generally viewed low on a use of force options scale. Is someone is sprayed with OC, it will temporarily make their eyes swell shut, skin feel like its burning from the heat, and can give a person the burning effects sensation to the nose and mouth as well, but it really hasn't caused a permanent injury so liability is low as compared to firearms or impact tools.
A lot of our Officers run and bike with a firearm carried in a chest holster, like the ones from SurvivalSheath.com
CY6
Greg Sullivan "Sully"
SLR15 Rifles
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