What are the three essential requirements to produce fire? How
fire extinguisher is useful for controlling the fire.
NCERT Class VIII
Science - Exemplar Problems
Chapter 6. Combustion and Flame
Answers
Three essential requirements to produce fire are :
- combustible material
- oxygen supply
- Ignition temperature [heat ]
To extinguish a fire we need to remove one of the essential requirement listed above to produce fire.
So fire extinguisher mostly cut off the supply of air or to bring down the temperature of fuel or both.
Most common Extinguisher used is water which will bring down the temperature .
But water should not be used on fire due to short circuits or due to petrol.
For fires involving electrical equipment and inflammable materials like petrol, then carbon dioxide (C02)is the best extinguisher.
As C02 is heavier than oxygen, covers the fire like a blanket. Since, the contact between the fuel and oxygen is cut off, so the fire can be controlled.
The three essential factors (triggers) for producing fire are air, fuel, and the heat to acquire the ignition point.
Different types of fire extinguishers are available in market, however, the central idea is to supply a trigger that will reduce the heat for igniting the fire.
Alternatively, it is needed to separate fuel from air, which exactly the fire extinguishers do.