Pepper sprays for your key chain and the like do not work on bears. The minimum size of for bear pepper spray is 7.9 ounces or 225 grams. Each bear deterrent will contain an EPA registration and establishment number, date code and the words “bear deterrent,” “bear spray,” “bear pepper spray,” “bear mace” or “bear repellant.” Bear repellant is not a very suitable word for this product and only one manufacturer uses it. The word repellent can confuse the user in to thinking that they can spray themselves or equipment like you do a bug repellent spray.
This is NOT true nor is it the proper way to use bear deterrent. You need to actually spray low in front of the charging bear, for it to be used correctly.
This creates a protective barrier between you and the animal. In 1999, the EPA wanted to specifically label bear spray as a repellant. However, this misleads the public and the vendors into thinking that this product was to be applied to themselves and the site or equipment just like bug repellant spray. Mark Matheny worked diligently to change the word from repellant to deterrent and to stop the misuse of the product and to explain further the proper use of the spray for deterring a potential bear attack. Even though the words deterrent and repellant have the same meaning, repellant is used in relation to insect spray so commonly that deterrent is a much better fit.