Recent events in both the United States and overseas, have seen the use of tear gas and pepper spray increase dramatically. They are both non-lethal forms of crowd and individual control which cause immense pain to prevent an individual or group from continuing to act in a certain manner. The rights and wrongs of this are beyond our purview, our question is simpler is their use a fire hazard?
Most tear gas in use today is chosen because it is not flammable and pepper spray is categorically not flammable due to very high water content. It will depend on the type of tear gas, as there are a few varieties.
This is not an uncommon question based on some events in the news. Let’s look at the different types of tear gas and their flammability. Here’s what you need to know.
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Also read: What Makes Something Flammable?
Table of Contents
What Is Tear Gas?
Tear gas, which is often known in chemical and law enforcement circles as a “lachrymator agent” or “lachrymator” (the word “lacrima” is Latin for “tear”) and is sometimes called “mace” by civilians, is not a single product.
It is, in fact, a group of chemical weapons that are meant to produce tears and pain to prevent an individual or group for continuing in their behavior.
This group of chemicals can include OC gas (also known as pepper spray), PAVA (nonivamide), bromoacetone, xylyl bromide, CS gas, CN gas and CR gas.
It may also include “Mace” which is a brand of tear gas (and hence, why many civilians use the term as a catch-all for tear gasses).
Tear gas is used mainly for riot control because, ironically, its use in war is forbidden by many different international treaties.
It is not fully understood what the effects of tear gasses on human beings are.
Evidence shows that in the short-term it may cause tears, respiratory and eye pain, bleeding, skin irritation and even temporary blindness.
In the long-term effects may include respiratory diseases, eye injury, eye disease, damage to the cardiovascular system, dermatitis and damage to the gastrointestinal system.
In the most severe cases, it may even cause death. This is particularly true in situations where high levels of tear gas are dispersed inside a small, enclosed space.
Is Tear Gas Flammable?
Most forms of tear gas in current use are supposedly selected for their lack of flammability and the majority of tear gas agents will not burn.
However, in light of the Waco disaster, it might not be a good idea to believe this absolutely.
Also read: Is Butane Flammable?
Burning Tear Gas in Waco
According to the FBI, in 1993 and 1995, the tear gas chosen for use on the Waco compound was absolutely not flammable and could not burn.
Then, in 1999, it did an about face and, as reported in the Washington Post ,the FBI admitted that they had used a “very limited number” of incendiary gas cartridges on the last day of the infamous siege of the Branch Davidian sect’s home.
The gas in question, was orthochlorbenzalmalononitrile, or CS gas as it is better known. It’s not really a gas at all, in fact, it’s a fine white powder and like many other powders it is flammable.
Worse, when CS is burned, it produces hydrogen cyanide which is a deadly poison (it was the gas used in the infamous “showers” of the Auschwitz Concentration Camp).
So, is tear gas flammable? It appears that some forms of tear gas are flammable though the majority seem not to be based on the available data.
What Is OC Spray?
Pepper spray uses the chemical “oleoresin capsicum” (which is why it is also called OC spray) a derivative of peppers to act as a lachrymatory agent.
It is as effective on dogs and bears as it is on human beings and it was originally intended to be used as a defense against wild animals.
It is used in riot control but has been, supposedly, banned for use on docile persons after the police sprayed peaceful protestors in 2011, protesting at the University of California.
Is OC Spray Flammable?
Pepper spray is a solution of the pepper oil extract and water, and the vast majority of the liquid is water.
This means it won’t burn, because even though the oil is slightly flammable, there’s so much water present that it will immediately extinguish the fire.
However even though pepper spray is not flammable, that doesn’t mean that pepper spray can’t catch fire.
When used for crowd control, pepper spray won’t travel very far if you put it in a squeezy bottle (like the ones used to produce mist for plants), so it needs to be placed inside an aerosol delivery system and then be propelled onto the unfortunate recipients.
The propellant is often flammable and under the wrong circumstances, it will catch fire and then the pepper spray itself will catch fire because the water evaporates leaving burning oil.
How Hot Is A Can Of Tear Gas?
When stored, a can of tear gas is the same temperature as the ambient temperature around it.
However, once a can of tear gas is fired into a crowd, this changes dramatically.
In order to disperse, say, CS gas, the CS needs to be a gas. That means it needs to be 310 degrees Celsius or 590 degrees Fahrenheit to boil.
The CS gas cannister, thus needs to heat up the CS gas and then spray it everywhere.
And indeed, it gets so hot that the cannister and the spray that escapes are more than hot enough to burn skin.
This may, in part, be the reason for the fire at the Waco compound too.
Do Tear Gas Cannisters Explode in Heat?
Unfortunately, the same reaction as that described above, means that a tear gas cannister gets very hot, indeed and if the gas is not escaping quickly enough, it will expand inside the cannister.
If it expands enough, it will explode and shower protesters in gas, shrapnel, solvents, etc. there have been several recorded incidents in which protestors have received brain injuries due to the consequences of exploding tear gas cannisters.
Pepper spray is kept in aerosolized cannisters and while it does not require a similar reaction to CS gas to be useful (pepper spray is perfect usable at room temperature and does not need to be turned into a gas), you must take the same precautions as you would with any other aerosol.
Don’t leave the cannister in a hot car, don’t place it in direct sunlight, don’t throw an empty cannister on an open fire, don’t puncture the cannister, etc. as under the right circumstances the cannister could violently explode.
Can A Taser Ignite OC Spray?
Yes, in fact, in the video below you can see a famous incident in France where a protestor was doused in pepper spray and then tased.
This provided an electrical spark which caused the propellant for the pepper spray to ignite and the protestor to be seriously burned.
Assuming you haven’t been coated in a flammable liquid or powder prior to being tased, tasers cannot normally set a person on fire.
Electric charges don’t ignite people or most forms of clothing.
Does Baking Soda Help With Tear Gas?
Baking soda may help to neutralize some forms of tear gas.
It should be mixed in a ratio of 3 teaspoons to 8 ounces of clean, fresh water.
It should be applied to the eyes to help neutralize the compound and then the eye should be flushed with copious amounts of clean, fresh water. (If you wouldn’t drink the water, don’t put it in your eyes – you’re asking for an infection).
What About Saline Solution?
The United States Army and the various manufacturers that produce CS gas say that saline or plain water are the best way to remove CS gas from your eyes and skin.
It is very important to remember that CS gas sticks to clothing, hair, belongings, etc. and you may need to drench yourself in order to remove it fully.
A bandana soaked in vinegar will help prevent tear gas from getting into your lungs if you place it over your mouth and nose, you should aim to get clear of the gas as fast as possible, though, as it will do nothing for your eyes.