Foam fire extinguishers are a type of fire extinguisher used for class A and class B fires. Sometimes called AFFF (aqueous film-forming foam) fire extinguishers, these fire safety tools are suitable for use for types of fire involving organic solids and flammable liquid. These extinguishers are ideal to have in your house or in some commercial places like offices.
The AFFF foam fire extinguisher is colour coded just like any other fire extinguisher. Its coloured label is cream. One important thing to note about this fire safety equipment is that foam fire extinguishers are never suitable for use on class F fires involving live electrical equipment, and they are not typically effective for flammable gas fires (the other aspect of class B fires).
What Is A Foam Fire Extinguisher?
Foam fire extinguishers are manufactured to contain a mixture of foam and water along with compressed nitrogen, which is used as the propellant for discharge of the material. AFFF foam fire extinguishers are a little similar to water extinguishers, however, they contain a concentrated foaming solution along with the water, while water extinguishers just contain water.
Since water is difficult to compress, water fire extinguishers can fall short in how much fire-fighting material they can contain. Foam fire extinguishers, alternatively, function more like CO2 extinguishers in that the volume of the foam is significantly larger than the body of the can itself.
The AFFF abbreviation is a technical explanation of what happens when a foam extinguisher is used. First, water (the A for aqueous) is utilized to make a foam (F) that resembles a film (F) over burning fuel, which cuts off the air supply of the fire (F). The abbreviation itself means “aqueous film-forming foam.”
How Does A Foam Fire Extinguisher Work?
Foam fire extinguishers work by targeting burning liquids (examples: petrol, diesel, oils) or organic materials (wood, paper)by effectively smothering the fire with foam. They also assist in absorbing heat, as the foam they discharge is cool and contains a significant amount of water.
All fire extinguishers are designed to cut off the key elements of a fire. Oxygen and heat are two of those elements that AFFF foam extinguishers deplete from a fire.
What Are Foam Fire Extinguishers Used For?
Foam extinguishers are suitable for most fires involving flammable liquids (NOT gaseous fires) and organic material like wood, paper, or fabric. These types of fires are classes B and A, respectively.
The interesting thing about foam fire extinguishers is their primary material’s ability to expand once it hits the air. When a person discharges the foam solution to spray a fire, the foam expands in the air and acts as a blanket to smother the fire, cutting off its supply of oxygen, cooling it down, and extinguishing it.
How To Use A Foam Fire Extinguisher?
First, you will need to be able to correctly identify the foam fire extinguisher through its coloured label, which will be cream. This label can be found towards the top of the red, cylinder-shaped extinguisher.
Like any other fire extinguisher, the foam fire extinguisher is to be used through the utilization of the “PASS” method.
The PASS method is as follows: 1. “P” for pulling the pin, 2. “A” aim at the fire, 3. “S” squeeze the handle, and 4. “S” sweep the nozzle from side to side.
If you know the PASS method, you know how to use any type of fire extinguisher, including foam fire extinguisher. It’s easy to memorize and a perfect addition to your fire safety toolbox.
Foam Fire Extinguisher Tips
Just like any fire safety equipment, it’s important to keep up the maintenance of a foam fire extinguisher.
Make sure that you get your fire extinguisher inspected as much as local fire safety ordinances recommend. This can be as often as a monthly inspection.
After you use a foam fire extinguisher, be sure to either replace or recharge the equipment. As with any fire, you never know when the next one will be, so it’s important to be sure that your foam fire extinguisher is fully loaded with the foam solution.
Lastly, it’s vital to understand that foam extinguishers should never be used on electrical fires. This could result in terrible damage or an even bigger fire.