Types of Fire Extinguishers

Fire. Scorching heat. Crackling flames. Destruction. Death.  An untamed fire evokes feelings of fear in those entrapped by and observing it. The damage it leaves in its wake can also be devastating and life altering. Fire extinguishers have been used for centuries as immediate solutions for putting out fires.  Their history dates to as far back as 200 BC. In 200BC, Ctesibius of Alexandria, a Greek physicist, created a hand pump that used the principle of compressed air to deliver water to a fire. The next advancement in fire extinguisher history was the squirt. In fact, squirts were used during the Great Fire of London in 1666.

These simplified versions of fire extinguishers were drastically upgraded in 1723.  Ambrose Godfrey, a reputable chemist, created an encased fire extinguishing liquid. Gun powder was found in a pewter chamber within the liquid so that when the devices’ fuses were lit, the gunpowder would explode and scatter the solution.  The device was a little larger than a hand and resembled a grenade.

The first fire extinguisher that was most similar to the one we presently use was created by Captain George William Manby in 1818. His invention was a 4 gallon copper vessel consisting of 3 gallons of water and potassium carbonate solution engulfed by 1 gallon of compressed air.  As a member of the British military, Manby had repeatedly seen firemen being unable to reach the top floors of burning buildings. The compressed air of his device facilitated the directional flow of the fire extinguishing solution, thus enabling firefighters to reach the previously unreachable. His invention was, however, useless against oil and electrical fires.

About 48 years later, the soda-acid fire extinguisher was developed by the Frenchman Francois Carlier. Each cylinder for this fire extinguisher had between 1 to 2 gallons of a mixture of water and sodium bicarbonate. The mixture also had a vial with concentrated sulphuric acid suspended in it.  Atop the mixture was a screw cap containing a plunger mechanism with a safety guard.  When the plunger was pressed, the vial was broken and the sulphuric acid combined with the water and sodium bicarbonate mixture. This reaction produced carbon dioxide which forced the liquid through the internal pipe and out of the extinguisher’s nozzle. This was truly the beginning of the creation of the fire extinguisher we use today.

In 1881, two Englishmen, Read and Campbell, invented the cartridge-operated fire extinguisher.  They later developed the Petrolex which was specifically intended for automobile use.  In the 1890s a carbon tetrachloride version was created. The device was a glass bottle filled with liquid which was intended to be thrown at the base of the fire. For 60 years, this revision was used in automobiles until it was withdrawn due to being highly toxic.  In the 1940s, a less toxic version was created in Germany. It used 1940s and was used until 1969. Between the 1950s and 1970s, two compounds (Halon 1211 and Halon 1301) were invented. They have been used in fire extinguishers since then.

Fire extinguishers have certainly had a rich history. This rich history has, however, resulted in very efficient extinguishers that can be used by anyone, anywhere.  Knowing the types of fire extinguishers and how to use them effectively can mean the difference between preventing a small fire from spreading and allowing a fire to perpetuate causing terrible destruction or even death. There are 6 types of fire extinguishers: water fire extinguishers, foam fire extinguishers, foam fire extinguishers, dry powder fire extinguishers, carbon dioxide fire extinguishers, wet chemical fire extinguishers, and fire extinguishers for metal fires. Each type of fire extinguisher is used for a different class of fires. The table below describes the materials that cause each class of fire.

The fire extinguishers described below are used for different classes of fires. Pay attention to their uses and ensure that you have the correct one in your home, office, and motor vehicle.

Water Fire Extinguishers

Used exclusively for class A fires, water fire extinguishers utilize water to eliminate the fire’s heat. They are the most inexpensive and widely used fire extinguishers. These fire extinguishers don’t have any harmful chemicals.

Foam Fire Extinguishers

Used exclusively for class A and B fires, foam fire extinguishers are comprised primarily of small air-filled bubbles. These bubbles have three components: water, foam concentrate, and air.  Since they have a lower density than oil and other heavy liquids, they are able to limit the effects of these materials as fire sources.

Dry Powder Fire Extinguishers

Dry powder fire extinguishers are the best fire extinguishers to have in your home, office, or motor vehicle. They cover class A, B and C fires. Using them to eliminate a class C fire does, however, mean that you have to eliminate the gas source first.

Carbon Dioxide Fire Extinguishers

Ideal for use in class B and D fires, carbon dioxide fire extinguishers should be used with caution.  It is possible that the fire could re-ignite after it has been extinguished.  These fire extinguishers work on the principle that carbon dioxide smothers oxygen. The cold temperature of the carbon dioxide used in this extinguisher also removes the heat from the fire.

Wet Chemical Fire Extinguisher

Class A, B, and F fires are extinguished using wet chemical fire extinguishers. These fire extinguishers are primarily used on class F fires. They contain a solution of potassium.  When sprayed, the potassium mist cools the fire and lowers the temperature. The potassium also reacts with the hot oil resulting in the oil being coated in non-combustible soapy foam. It also prevents the oil from splashing onto the person attempting to put out the blaze. Since wet chemical fire extinguishers focus primarily on class F fires, they are ideal for restaurants and areas where oil and fat are used extensively.

Fire Extinguishers for Metal Fires

Special fire extinguishers are available for putting out class D fires.  These extinguishers are made with a low velocity applicator. Laboratories and industrial facilities find these fire extinguishers particularly useful.