I took a 3 hour fire extinguisher training course recently. I tried to get by buds Jamal and Daniel to go, and I was shocked that they weren't interested. Then I told my dad and he thought there was nothing to learn, because how to use one was so obvious. Anyway, it was awesome and I recommend it to anyone.
Answer these questions for yourself:
1) How much time should you spend trying to extinguish a fire before you give up and get the hell out?
2) Fire extinguishers should be used in short bursts, or a continuous stream?
3) What kind of extinguisher should you not use on a liquid fire (e.g. burning gasoline)?
4) When getting out of a burning building, does it help to have cloth covering your face? What else should you do while running?
In the training we saw a video about how fast fire spreads. It was a dorm room with the smoke ventilated out of it. The room gets so hot after four minutes that other stuff in it spontaneously combusts. Even more disturbing is another video I saw long ago that didn't take out the smoke. It was a burning Christmas tree, and within 30 seconds the smoke completely filled the room. You couldn't see shit.
After the videos we all got to put out a gasoline fire! I don't understand how someone could pass up an opportunity to do this. Now to answer the questions...
1) 30 seconds. If you haven't put it out by then, you probably won't, and the extinguisher is probably close to empty. Fire increases in size very quickly, so get out. Always pull the fire alarm before trying to extinguish the fire.
2) A continuous stream. Fire will spread to where you just got rid of it, destroying all your progress. Push the fire away from you, continuously spraying back and forth, from the point nearest you to the farthest, at the base of the flames. Hold the extinguisher upright at all times.
3) Never use a water-based extinguisher on burning liquids. It is liable to dangerously spread it. Many extinguishers are not water-based.
4) In a burning building, most people die of smoke inhalation or heat, and not the flames themselves. Covering your mouth with cloth, wet if you can, is great. Also, run with your head low to the ground. Standing up might be deadly.