Would you set fire to an orphanage if it meant you got to see this guy spraying his hose?
CO2, dry powder and halon systems will all interfere with your breathing. I'm guessing you have halon for some reason. Powder doesn't air out and CO2 doesn't really work on fuel fires. A blast of halon would do nothing, the bear probably wouldn't notice. If you unloaded a powder extinguisher in a bear's face it would be unpleasant for the bear. The powder would get in to its eyes, mouth and lungs. I wouldn't like someone to do it to me. When I put out a car fire the dust made it difficult to breathe for several minutes, but not enough to stop anyone. The bear probably wouldn't be put off by it. Might work on a dog that was just playing, but an animal attacking would just shrug it off.
Beedsarefunak is a friend of mine here in Alaska. The two of us have hunted all over the US, but mostly in the Rocky Mountains and Alaska. I can tell you we have spent a great deal of time around bears. And this guy actually crawled into a bear den and took a picture of the bear! Lol he’s nuts! Anyway I agree with Slider72, Beedsarefunak, and some of the others; fire extinguishers will not stop a bear. It may startle him but it wont stop him.
There have been bear encounters where the victim has shot the bear, recently a hiker in Alaska fired 6 .38 Special rounds into a large bear, and the bear ate him. The bear was later killed by a hunter with a high powered rifle (7mm Magnum I think). It is doubtful that this would work on a bear. However, it might work with a mountain lion. Mountain lions will not attack if they feel as if their prey is going to prove to be too much trouble, this may startle them enough to disuade the animal from an attack.
Hmmm.since the contents of a fire-extinguisher are under considerable pressure, you could theoretically shove it in the bear's mouth and shoot it with a high-velocity round, exploding the cannister and the bear's head with it..would certainly be more sporting than blowing up the whole bear with a LAW like the bloke from Rat Patrol did in the silly flick Grizzly.
