Though the Interagency Grizzly Bear Committee, created in 1983 to lead the recovery of the grizzly bear in the lower 48 states, does not endorse any particular commercial bear spray, it points out in its literature that proper use of bear spray can:
In a study in the April 2008 edition of the Journal of Wildlife Management, Tom Smith examines "The Efficacy of Bear Deterrent Spray in Alaska." The study shows that in 72 cases where people use bear spray to defend themselves from brown, black and polar bear the spray stopped brown bears 92 percent of the time and 98 percent of the people involved were uninjured.
In the rare case of a conflict, bear spray, a high-pressure extract of about two percent capsaicin, the chemical that makes peppers hot, and other related capsaicinoids, can get the job done. Recent incidents show bear spray to be more effective than a bullet in diverting or stopping a charging bear, according to the Center For Wildlife Information in Missoula.
One way to begin is to check out the different brands available on the Internet or at your local sporting goods store. Many manufacturers offer helpful product comparisons and detailed user instructions on their Internet web sites. Be especially careful to confirm that you are looking at products registered with the EPA and that are intended specifically for use on bears.
Features to assess when selecting a manufacturer include:
Manufacturers generally recommend practicing the steps necessary to use bear spray including arming the container, spraying and then restoring the safety clip to disarm the container. First time users will also want to take a test spray or two. Because the spray is so forceful, it may require some practice to control it, especially if there is any wind. The down side is that every test spray reduces the canister's effective spray time. It is important to track the time remaining on a canister carefully.
The most intense effects of bear spray may last 30-45 minutes. It is potent enough to cause extreme discomfort and damage to the eyes if it is accidentally released at close range. Flushing the affected skin with water can help, but expect to be uncomfortable for awhile.
Do not plan to transport bear spray on commercial airlines, but you can identify suppliers on the Internet in the area where you plan to recreate. Also be aware that extreme heat or cold may affect the performance of the product. Canisters have been known to explode if left in a vehicle in summer. Each canister also has an expiration date.