Fire Extinguishing Theory

The extinguishment of fires is based on an interruption of one or more fire ingredients. With flaming combustion the fire may be extinguished by reducing temperature, eliminating fuel or oxygen, or by stopping the uninhibited chemical chain reaction. If a fire is in the smoldering phase, only three extinguishment options exist: reduction of temperature, elimination of fuel, or oxygen.

One of the most common methods of extinguishment by cooling is dependent on cooling the fuel to a point where it doesn’t produce sufficient vapor to burn. Solid fuels and liquid fuels with high flash points can be extinguished by cooling. Low flash point liquids and flammable gases cannot be extinguished by cooling with water as vapor production cannot be sufficiently reduced.

Reduction of temperature is dependent on the application of an adequate flow in proper form to establish a negative heat balance.

In some cases, a fire is effectively extinguished by removing the fuel source. This may be done by stopping the flow of liquid or gaseous fuel or by removing solid fuel in the path of the fire. Another method of fuel removal is to allow the fire to burn until all fuel is consumed.

The method of extinguishment by oxygen dilution is the reduction of the oxygen concentration in the fire area. This can be accomplished by introducing an inert gas into the fire or by separating the oxygen from the fuel. This method of extinguishment will not work on self-oxidizing materials or on certain metals as they are oxidized by carbon dioxide or nitrogen, the two most common extinguishing agents.

Найдите в тексте (задание № 10) и выпишите английские эквиваленты к данным словосочетаниям.

1. тушение пожаров

2. пламенное горение

3. устранение горючего вещества или кислорода

4. непрерывная цепная реакция

5. фаза тления

6. уменьшение температуры

7. твердое горючее вещество

8. высокая температура вспышки

9. легковоспламеняющиеся газы

10. отрицательный тепловой баланс

11. удаление источника топлива

12. уменьшение концентрации кислорода

13. введение инертного газа

14. самоокисляющиеся вещества

15. огнетушащие средства

Закончите предложения, выбрав подходящее слово. Переведите предложения на русский язык.

cooling removing diluting reducing smoldering

1. Sometimes, a fire is effectively extinguished by _____ the fuel source.

2. A nozzle is used with a hose to _____ a fire spray of water.

3. _____ of temperature is one of the firefighting options in flaming combustion.

4. Last stage of a burning process is a _____ phase.

5. _____ is the reduction of the oxygen concentration in the fire area.

Ответьте на вопросы к тексту из задания №10.

1. What is the extinguishment of fire based on?

2. How can you put out the fire with flaming combustion?

3. What is the most common method of extinguishment?

4. Why can’t you use water on low flash point liquids and flammable gases?

5. What does the method of extinguishment by oxygen dilution mean?

Дата добавления: 2015-08-13