How a fire extinguisher works

A fire extinguisher is an essential part of every house and business. Most of the time, these things are never used, just sitting on the wall collecting dust. But if an emergency strikes, they can save your property, or even your life. This speech is used to inform how a fire extinguisher works, and what type of extinguisher works best on different fires.

I. What is a fire?
A. A fire is the result of a chemical combustion reaction, typically a reaction between oxygen in the atmosphere and some sort of fuel.
B. There are three elements involved in causing a fire.
1. Extreme heat
2. Oxygen
3. Fuel

II. What is a fire extinguisher?
A. Sturdy metal cylinder filled with water or a smothering material inside.
B. Designed to remove at least one of these elements so that a fire will die out.

III. How does a fire extinguisher work?
A. When you depress a lever at the top of the cylinder, the material is expelled by high ...