Controlling Fire: Combustion & Flame

Controlling Fire: Fire is created by combustion, it can be both good and destructive. To cook our food, we need to light the fire on a gas stove. We are unable to cook without the appropriate use of fire. However, a fire that starts in a house, an office, a factory, an oil tanker, a gasoline pump, or electrical equipment is dangerous. It has the potential to result in the loss of lives and property. Such fires must be brought under control and put out as soon as possible. Firefighting is the process of extinguishing a fire. In this article, let’s understand how to control the Fire in detail.

Fire Service

Every city and town has a Fire Brigade Station that provides fire protection. The Fire Brigade’s firefighters are experts at putting out fires. Everyone in our city should know the Fire Department’s phone number. The Delhi Fire Department’s telephone number is 101. If a fire breaks out in our house or community, we must immediately call the Fire Department. We should also be aware of the causes of fire and the many methods for putting out fires.

Components of Fire

A fire needs to have three elements to start: fuel (combustible substance), air (or oxygen), and heat. The fire will stop and the flame will be doused if any of these three things are removed. A fire can be put out in three ways:

1.  By removing the source of ignition (combustible materials).
2. By removing the heat (using water to cool).
3. By cutting off the air supply to the burning substances (with carbon dioxide, etc.)

We will now discuss these three ways of extinguishing fire in detail, one by one.

Study Importance of Water Here

Remove the Fuel (or Combustible Substances)

A fuel (or combustible substance) is a portion of food for fire. So, when the fire starts in a room, all the combustible substances like furniture, clothes, books, etc., (which can burn quickly) should be removed at once so that fire may not spread. If possible, the cooking gas cylinder should be removed, and electricity should be switched off.

If the fire is near a pile of wood that could provide fuel to keep the fire going, the pile of wood should be removed from there as soon as possible. However, it is almost never practicable to remove all combustible things from the place of fire.

Remove the Heat

Water is used to remove heat from a burning substance and cool it down to the point where it can no longer burn. For ordinary fires, water is the most common extinguisher. Water extinguishes fire by cooling the burning substances. When water is dropped on a burning object, it cools below the temperature at which it ignites and stops burning. The fire gets extinguished.

For example, when a fire brigade man throws a strong stream of water on a building on fire, the burning materials get cooled below their ignition temperatures, and the fire is extinguished. The water vapour formed by the action of heat on water surrounds the burning object and helps to cut off the air supply. This also helps in extinguishing the fire.

 Thus, firemen extinguish the fire by throwing water under pressure on burning houses, factories, or other buildings. Waterworks as a fire extinguisher only when things like wood and paper, etc., are on fire. However, the fires caused by burning oil (or petrol) or those caused by electricity cannot be extinguished by using water. This is explained below.

Water cannot extinguish a fire caused by burning oil or petrol (for example, a fire in a frying pan, oil tanks, petrol pumps, and airports). It is because of the following reason: Water is denser than petrol. As a result, when water is put over a burning oil (or petrol), it settles. The oil (or petrol) floats in the water and burns. As a result, flames started by burning oil (or petrol) cannot be put out by simply putting water on them.

Water should not be used to put out fires caused by an electrical short-circuit in an electrical appliance or in electric wiring. This is due to the following factors: Water generally conducts electricity to an extent. As a result, throwing water over burning electrical equipment (or burning electric cables) might cause shock to firefighters. As a result, water cannot be used.

Cut off the Supply of Air

Many fires can be put out by shutting off the supply of oxygen to the burning materials. A burning substance’s air supply can be cut off in various ways, including covering it with carbon dioxide, sand (or soil), a blanket or a damp cloth, and so on.

Carbon dioxide gas fire extinguishers are used to put out electrical fires. Because carbon dioxide gas is denser than air, it forms a layer around burning materials. A blanket of carbon dioxide surrounds the fire, preventing fresh air from reaching the burning substances.

 Because the burning substance is deprived of oxygen from the air, it stops burning. In this way, the fire gets extinguished. Please note that carbon dioxide gas neither burns itself nor supports burning (or combustion). An added advantage of carbon dioxide is that it does not harm the electrical equipment. The fires caused by burning inflammable materials like oil or petrol are also extinguished using carbon dioxide fire extinguishers.

The carbon dioxide used for extinguishing the fire can be stored as a liquid at high pressure in cylinders (called fire extinguishers). When carbon dioxide is discharged from the cylinder, it expands dramatically in volume and cools rapidly. As a result, carbon dioxide forms a blanket around the burning substance, which cools it down. Carbon dioxide is a good fire extinguisher because of this. Another method to get carbon dioxide for extinguishing a fire is to sprinkle a large amount of dry chemical powder over it, such as sodium bicarbonate (baking soda) or potassium bicarbonate. These chemicals disintegrate under the heat of the fire, releasing carbon dioxide into the environment. The carbon dioxide then puts out the fire.

Throwing Sand (or soil) over a Tiny Fire will put it out

For example, when sand is placed over burning kerosene oil, the sand covers it. Because the sand cuts off the air supply to the burning kerosene oil, the fire goes extinguished. The cooking oil fire in a frying pan in the kitchen can be extinguished by covering the pan with a fire blanket or a damp cloth. When the frying pan is covered with a fire blanket or a damp cloth, the supply of air to the burning cooking oil is cut off, and hence the fire gets extinguished.

If a person’s clothes working in the kitchen catch fire, the person is immediately covered with a blanket. When a person’s burning clothes are covered with a blanket, the supply of air to the burning clothes is cut off. Hence the burning (or fire) stops.

Fire Control

Fires are classified as Class-A fires, Class-B fires, Class-C fires, Class-D fires, and Class-K fires in the United States; however other countries may have alternative categories. Each class represents a distinct form of fire that necessitates a distinct control mechanism based on its origin.

Understanding the reason is critical to use the proper fire extinguisher; using the incorrect extinguisher might make the fire worse or make it uncontrollable. For example, using a class A, B, or C fire extinguisher on a chemical fire, will generate an explosion and will perform the reverse of what the extinguisher is designed to do. Fire extinguishers, type A, B, or C carbon dioxide fire extinguishers, and water-based fire extinguishers are among the various types of fire extinguishers.

Summary

We can prevent a substance from catching fire by not allowing its temperature to reach the ignition temperature. We call the fire brigade to extinguish the fire in cities, but we should always have a fire extinguisher at home, office, and schools. The fire extinguisher helps in cutting off the supply of air so, the fire is extinguished. In this article, we learnt about how to control fire in different ways.

FAQs on Controlling Fire

Frequently asked questions related to controlling fire is listed as follows:

Q.1. What are the three ways of controlling fire?
Ans: There are three ways to put out a fire:
1. By removing the source of ignition (combustible materials)
2. By removing the heat (using water to cool)
3. By cutting off the air supply to the burning substances (with carbon dioxide, etc.).

Q.2. What is the basic principle of controlling the fire?
Ans: A fire requires three conditions: fuel, oxygen, and heat (or ignition source). The fire triangle is a common representation of these three requirements. Fire does not occur if one of these requirements is missing, and it is extinguished if one of them is removed.

Q.3. Why is it important to control fire?
Ans: Thousands of businesses are affected by fires each year, resulting in injuries, a loss of client trust, and property damage. You may help prevent accidents to your employees and guests, as well as costly damages and potential fines, by developing a fire prevention and preparedness programme.

Q.4. What can control fire?
Ans: Water is the most common fire extinguisher. Carbon dioxide is the best extinguisher for fires involving electrical equipment and combustible fuels such as gasoline. Carbon dioxide, being heavier than oxygen, acts as a blanket over the flames. The fire is controlled because there is no contact between the fuel and the oxygen.

Q.5. What will happen if the fire goes out of control?
Ans: A fire that is defined as “out of control” is one that is blazing around its perimeter and has the potential to expand into unburned areas. Because the flames of these burn out quickly, the majority of a fire’s interior is blackened, with just heavy fuels like logs and branches burning.

Q.6. What are the 5 types of fire extinguishers?
Ans: There are five basic types of fire extinguishers: wet chemical, carbon dioxide, dry powder, foam, and water.

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