What Methods can be Used to Control Fire?
Combustion is a good phenomenon as it liberates energy in the form of heat and light. But too many flames or even combustion of the substance on a large scale is very dangerous as fire can spread rapidly and can get everything burnt in itself. Hence, the fire needs to be controlled.
Let us look at some methods to control fire.
The three basic requirements for combustion are ignition temperature, fuel, and oxygen. Cutting off the supply of any one of these can lead to the termination of combustion.
Water
When a spray of water is thrown on the flames, the temperature is lowered. As a result, the combustible substance no longer burns.
Compressed carbon dioxide
All combustions cannot be controlled with water. For example, if an electrical gadget or petroleum or any kind of oil catches fire, we cannot spray water in these flames.
To put out such fires, fire extinguishers are used. These cylinders contain compressed carbon dioxide. Spraying the compressed gas douses the flames.
How does the compressed CO2 in a fire extinguisher put out flames?
Carbon dioxide is heavier than oxygen. Thus, it forms a layer around the combustible substance. As a result, the supply of oxygen is cut off and the flames get extinguished.
Also, the temperature of compressed carbon dioxide is too low. Thus, the heat supply is also terminated. As a result, the fire gets easily and quickly extinguished.
Summary
| Basic Requirements for Combustion | Ignition temperature Fuel Oxygen |
| Methods to Control Fire | |
| Water | Reduces the temperature of combustible substance Cannot be used for electrical and oil-related fires |
| Compressed Carbon dioxide | Forms a layer around combustible substance and cuts off the oxygen supply Has low temperature, thus terminates heat |