Pepper spray has much to commend it: It is ubiquitous, affordable, effective and one of the only less-lethal ranged self-defense weapons available to civilians and it can go almost anywhere.
That is a big list of advantages for such a small can, and is reason enough for all kinds of people to carry pepper spray in order to keep themselves and their families safe.
Pepper spray is an excellent self-defense option even if someone carries a lethal weapon for defense like a knife or gun, since not every tactical problem needs to be solved with lethal force.
Because pepper spray is so convenient and so common it is naturally going to be carried and stored almost everywhere. What are the most popular places to keep pepper spray is in the door pocket or center console of an automobile.
Is this a good idea? Can you safely store pepper spray in your car?
No, in most climates you cannot safely store pepper spray in your vehicle. Pepper spray canisters should not be kept anywhere the temperature exceeds 120° F (48° C) or drops below 32° F (0° C).
Once these extremes are exceeded, there is an increasing likelihood that the canister could leak or burst, or the contents could be rendered less effective. Both extremes are easily reached in most locations during various seasons inside an automobile’s cabin.
In the remainder of this article we will provide you with further consideration for safely carrying and using your pepper spray in and around your vehicle.
What is Pepper Spray Made Of?
When people say pepper spray, they are usually talking about any kind of defensive spray.
Defensive sprays might be legitimate pepper spray, or OC (oleoresin capsicum), or they could be made up of a tear gas formulation which is chemically different.
The active ingredient in pepper spray is OC, which is the same stuff that makes red peppers so agonizingly hot and spicy. A little bit of OC will cause a warm sensation, and a lot of OC will cause burning pain.
Highly concentrated OC, like the kind found in pepper spray, causes severe symptoms like difficulty breathing, temporary blindness, inflammatory effects and coughing along with copious mucus production.
It’s one of the worst things you can go through, believe me!
But pepper spray is not just OC alone, as the actual solution will be made up of emulsifiers and other agents, often water but sometimes ethanol or other chemicals.
We need to find out if temperature in a vehicle will negatively affect any of these components, and thus negatively affect the operation or performance of our pepper spray.
Contents Under Pressure
Any quality pepper spray canister will be pressurized, so that the contents – OC aerosol, gel or foam – will be projected with some force when the activation button is pressed. This is what lends the pepper spray unit its range.
As you have probably learned prior to reading this article, pressurized containers should not be stored in hot ambient conditions because this will increase the pressure inside the vessel, potentially breaching the valve or, in extreme, cases the body of the canister itself.
Quite a few of us have learned this physics lesson painfully when a carbonated beverage bottle burst after being left in our vehicles during the summertime!
Pepper spray is no different, and since it is a pressurized vessel it shouldn’t be kept in your car, especially if you live in a hot climate.
Inside the cabin of an automobile with all the windows up, the ambient air temperature can easily be 20 to 30 degrees F hotter than the outside air temperature depending on conditions like shade, direct sunlight and other factors.
Even worse, interior surfaces like the seats, dashboard, armrests and steering wheel will become drastically hotter than the inside air temperature, potentially heating your pepper spray canister to a point where it will leak or burst.
Even if you live in a mild climate or are currently in a cold season you are not out of the woods. One of the major ingredients in pepper spray solution is water, with the OC compound being suspended within the water by an emulsifier, typically propylene glycol.
As we all know, water has a pretty modest freezing temperature, and though this might be affected by the presence of the other ingredients in the pepper spray as soon as you start closing in on 32°F you have to be worried about your pepper spray freezing.
If your pepper spray freezes the canister could rupture and you might not even know it at first.
But once the solution begins to thaw it will leak, and you might be in for a nasty surprise as you climb into your car only to start tearing up, or notice the burning “ring of fire” forming on your thigh if you stick the chilly canister back in your pocket.
In short, automobile cabins are subject to extreme temperature swings, and to ensure your pepper spray canister remains functional and in optimal operation you should not keep it in your vehicle.
Temperature Swings Reduce Effectiveness
Anytime your pepper spray canister is subjected to temperature extremes in excess of the manufacturer’s specifications, you might have to be concerned with a loss of effectiveness, both chemically in the form of a loss of potency or pungency, and mechanically in the form of reduced pressure meaning loss of range, or janky dispersal.
Both can be avoided by storing your pepper spray properly at all times, and in most places that means not keeping it in your vehicle for lengthy periods of time.
Since the functionality of a pepper spray canister is very difficult to assess without firing it, you’ll be facing a sort of dilemma:
You can test fire your pepper spray, risking both accidental exposure and depletion of its contents, or you can visually inspect it, looking for obvious damage and then just hoping for the best.
Though you should initially test fire every pepper spray canister you’re going to depend on for self-defense, periodic firings will only gradually deplete both pressure and the reservoir of OC solution, potentially setting you up for failure if you need it in a live event.
The best way to avoid this dilemma is to refrain from keeping pepper spray in your vehicle.
Will Pepper Spray Freeze?
Pepper spray can and will freeze, ruining it, although depending on the contents of your specific solution it will be more or less vulnerable to freezing.
Water-based solutions, which many formulations from major brands today are, are much more vulnerable to freezing in cold temperatures.
Ethanol-based solutions, which are falling out of favor due to the associated risks of accidental ignition, are more resistant to freezing.
However, keep in mind that extreme cold temperatures can negatively affect the performance of the solution itself or the operation of the canister even if it does not freeze solid.
You should always make it a point to protect your pepper spray from cold temperatures, and never leave it in a vehicle that won’t be running in extreme cold.
What About Bear Spray?
Bear spray is a little more than a supersized canister of OC spray, whether or not the formulation is any stronger than those intended for use against humans.
Because of this, you should never leave bear spray in your vehicle if it will be subjected to extreme heat or extreme cold, as it will be prone to the same sorts of failures and degradation that much smaller canisters of pepper spray are.
Always Keep an Eye on the Expiration Date
Pretty much every can of pepper spray made has an expiration date on it. You want to make it a point to discard or replace your pepper spray before this date since the manufacturer will not guarantee function or performance afterward.
With the exception of genuine tear gas formulations which may be more stable, defensive sprays utilize natural ingredients that do lose their potency over time.
Old, stale pepper spray is just not as effective as new, fresh stuff. But more than this, older solutions are more vulnerable to degradation from extreme temperatures.
Pepper spray, even the good stuff, is quite affordable, so you should get rid of your old pepper spray when it is closing in on the expiration date and replace it with a new one. Do this especially if you keep your canister in your car!
Keep it Firing by Keeping it Close
You can keep your pepper spray at optimal functionality by following this one simple trick: keep it on your person!
A typical self-defense size canister of pepper spray will easily slip inside a purse or clip onto a pocket, and so long as you are not living or working in truly extreme temperatures the canister should remain somewhere in its optimal storage temperature range between 32°F and 120°F (0° C – 48° C).
This alone ensures it is ready to use with no problems wherever you might go.
Although I can see the appeal of keeping a canister of pepper spray inside your vehicle, perhaps so you always have it with you, chances are you will have more cause to use it when you are outside your vehicle.
If your pepper spray is inside your car when you need it elsewhere, then it might as well be on the moon for all the good it will do you!
You can kill two birds with one stone and be ready to defend yourself simply by keeping your pepper spray on your person.
Storing pepper spray in your vehicle is a bad idea, as depending on weather and typical climate temperature swings can easily go below 32°F / 0°C and above 120°F / 48°C which is the typical temperature range that several major manufacturers of pepper spray recommend their units be stored at all times.
Tom Marlowe practically grew up with a gun in his hand, and has held all kinds of jobs in the gun industry: range safety, sales, instruction and consulting, Tom has the experience to help civilian shooters figure out what will work best for them.
1 thought on “So, Can I Store Pepper Spray in My Car?”
Thanks … great advice. What I want to know is how to transport bear spray in a vehicle, during hot temperatures. We all know that we buy the spray at the store, and on the way to the park we stop for something to eat … and the spray is going to be in the car. I can’t take it into the restaurant. How do I keep it in the car?