How Bear Spray Works

What is bear pepper spray?

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Bear spray isn't unlike pepper spray that humans use to protect themselves from other humans. The main difference is that bear spray can shoot farther and casts a wider effective area. There are three main ingredients in bear spray:

  • Oleoresin Capsicum (OC): oily residue from hot cayenne peppers. Capsicum is a naturally occurring ingredient that causes a burning sensation when sprayed in the face of an attacker. Food-grade OC is used to give heat to edibles like salsa.
  • Base fluid: mixed with the OC to dilute it. It's typically oil-based to prevent separation from the oily OC.
  • Aerosol propellant: used to eject the ingredients from the can to the threat.

These ingredients are packed into a canister with a trigger and safety to make sure that no unwanted sprays occur. There are six bear sprays currently registered with the Environmental Protection Agency (EPA), and they each have variations depending on what you're looking for. There are four such variations for you to consider when picking out your spray:

  • Spray duration: how long the spray can be ejected, typically four to nine seconds per canister.
  • Reach: how far the spray will shoot, roughly 18-40 feet (5.4 to 12 meters).
  • Weight: Since you'll be carrying it around, you want to consider how heavy it is.
  • Cost: How much do you want to spend to defend yourself from an attacking bear?

When choosing your spray, you need to decide what's most important for you. A blast that shoots 40 feet (12 meters) might make you feel safer from a fast-charging black bear, but it will run out sooner than one that only shoots 25 feet (7.6 meters). There's a group of bear experts called the Interagency Grizzly Bear Committee (IGBC) that made some recommendations for purchasing bear spray in 1999. They believe that a spray that reaches 25 feet (7.6 meters) or more and that lasts for at least six seconds at a minimum of 7.9 ounces is the way to go. Who are we to argue? Out of the six approved brands, only three met these recommended standards, so be sure to read up on brand specifications before you buy some spray and hike fearlessly into the woods.

It's also a pretty good idea that you buy a canister holster to wear on your person. What good is a $45 shot of "Counter-Assault" spray if it's stuck in the bottom of your backpack when Yogi and Boo Boo arrive? You might as well just cover yourself in gravy and lie down on the trail.

Let's say a bear approaches you in the woods. You should make a lot of noise -- blow a whistle if you have one or bang on some pots and pans. Wave your arms above your head to appear larger and more intimidating and back away slowly while avoiding eye contact. Under no circumstances should you ever run from a bear. This will inspire it to run after you and even though they're large, they can hit speeds of up to 30 plus miles per hour (48 kph). When all else fails, reach for the spray, flip the safety off, take aim and fire away. A yellowish cloud will shoot out, and ideally the bear will either get hit straight in the face or run into the cloud. Try and account for wind as best you can -- this is really the only variable unless you're being attacked by multiple bears. If that's the case, try your best to hit both of them.

Pack up your pic-inic basket and read on to find out what happens next.