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Fire extinguishers reading

Pre-reading activity

  1. What is a fire extinguisher?

  2. What do you know about different kinds of fire extinguishers? How do we operate them?

  3. How are fire extinguishers classified by their contents?

  4. Have a look at the words given in the box. Which of these substances can be used as the contents of fire extinguishers?

gas liquid dry powder foam water oil

Read the text using the list of the new words and check your answers after that.

a film -

the liquid -

dry

to conduct -

a lever -

a hand pump

to shoot -

to deposit -

the multipurpose -

pressure -

combustible –

Fire extinguishers

Fire extinguisher is a metal container filled with water or chemicals used to put out fires. Fire extinguishers are portable and easy to operate and can be used to put out small fires before the flames spread.

There are many kinds of fire extinguishers. The kind used depends on the type of fire involved. Fire prevention experts divide fires into four classes—A, B, C, and D—depending on the burning material. Class A fires involve such materials as cloth, paper, rubber, or wood. Class B fires involve flammable gases or such flammable liquids as cooking grease, gasoline, or oil. Class C fires involve motors, switches, or other electrical equipment through which electric current is flowing. Class D fires involve combustible metals, such as magnesium chips or shavings. Most extinguishers are labeled with the class, or classes, of fire for which they can be used. Class D fires require special extinguishers designed for specific metals.

But most other fire extinguishers can be classified, by their contents, as one of four types; (1) water, (2) foam, (3) liquefied gas, and (4) dry chemical.

Water extinguishers are used to fight only class A fires. Water conducts electricity, and so it must never be used on a fire involving electrical equipment. A water extinguisher is operated by a lever or a hand pump that shoots the water through an attached hose.

Foam extinguishers are used for class A and class B fires. They contain water and a foaming agent. One type of foam puts out fires that involve combustible liquids by depositing a film between the liquid and the flame.

Liquefied gas extinguishers may be used on class B and class C fires. There are two main kinds—carbon dioxide extinguishers, which contain carbon dioxide gas; and Halon extinguishers, which contain a gas called Halon. Larger Halon extinguishers can also be used to fight class A fires.

Dry chemical extinguishers are used on class B and class C fires. One type, the multipurpose dry chemical extinguisher, also can be used against class A fires. Dry chemical extinguishers contain a chemical powder and a gas under pressure.

1. Here are answers to the questions. What are the questions?

  1. _________? - Depending on the burning material

  2. _________? - Involve motors, switches, or other electrical equipment through which electric current is flowing.

  3. _________? - In about1837.

  4. _________? - The gas in liquid form under pressure in the container.

  5. _________? - Aluminium sulphate mixed with a sodium bicarbonate water-based solution to generate pressure.

  6. _________? - Effective on Class A fires.

  7. _________? - Involve flammable and combustible liquids, greases, and similar materials.

  8. _________? – A sodium bicarbonate, potassium bicarbonate, or potassium chloride base.

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