What are Foam Fire Extinguishers Used For?

In the battle against flames, foam fire extinguishers have become a trusted ally for extinguishing a wide range of fires. These versatile fire-fighting devices have gained widespread popularity for their effectiveness in extinguishing fires. So, what are foam fire extinguishers used for?

Foam fire extinguishers are used to combat Class B fires, which are fueled by flammable liquids such as gasoline, oil, and solvents. The foam forms a blanket that covers and smothers the fire, suppressing its ability to spread and reignite.

So, let’s dive into the world of foam fire extinguishers, discovering how these innovative devices stand as stalwarts in the fight against fire, ready to protect and save lives when it matters most.

What are Foam Fire Extinguishers Used For

What Are Foam Fire Extinguishers?

Foam fire extinguishers are a type of fire suppression device specifically designed to combat Class B fires. They are equipped with a special foam agent that, when discharged, expands and forms a thick, blanket-like layer over the fire. 

This foam acts as a smothering agent, cutting off the fire’s oxygen supply and suppressing its ability to spread. The foam also helps to cool down the flames, further aiding in extinguishing the fire. 

Foam fire extinguishers are found in various settings, including homes, offices, industrial facilities, and vehicles, due to their effectiveness in tackling liquid-based fires. 

How Do Foam Fire Extinguishers Work?

Foam fire extinguishers work through a combination of smothering and cooling mechanisms. Let’s explore the process in detail:

Composition of Foam Fire Extinguishers

Foam fire extinguishers are filled with a foam-forming agent, typically a mixture of water and a foaming agent like AFFF (Aqueous Film-Forming Foam) or FFFP (Film-Forming Fluoroprotein). 

These agents are specifically formulated to produce a foam that can effectively suppress fires fueled by flammable liquids.

Smothering Effect

When a foam fire extinguisher is discharged, the foam-forming agent is expelled from the extinguisher in the form of a spray or jet. As the foam-forming agent is expelled, it mixes with the surrounding air. 

This interaction triggers a chemical reaction that causes the agent to rapidly expand and transform into a foam. The foam quickly expands in volume, creating a thick, blanket-like layer that covers the burning liquid or fuel source.

Blanketing the Fire

The foam acts as a physical barrier between the fire and the surrounding oxygen. As a result, the foam suffocates the flames and prevents them from gaining access to additional fuel sources.

You know that oxygen is a fundamental component of the fire triangle, along with heat and fuel. By depriving the fire of oxygen, the foam fire extinguisher disrupts the combustion process and prevents the flames from sustaining themselves. This extinguishes the fire and prevents it from spreading further.

Cooling Effect

When foam is applied to a fire, it actively works to reduce the fire’s temperature, thus assisting in extinguishing the flames. As the foam comes into contact with the burning liquid or fuel source, it absorbs heat energy from the fire. 

This absorption occurs due to the foam’s high water content, which has excellent heat absorption properties. The water within the foam undergoes a phase change from liquid to vapor as it absorbs the fire’s heat energy.

By lowering the fire’s temperature, the foam fire extinguisher helps to diminish the fire’s intensity. The reduction in temperature inhibits the fire’s ability to sustain itself and limits its capacity to ignite nearby materials or surfaces.

Chemical Reactions

Foam fire extinguishers contain additives that enhance their fire suppression capabilities. These additives can undergo chemical reactions when they come into contact with the fire. These reactions can disrupt the combustion process, further extinguishing the flames.

Surfactants are a group of substances that are frequently added to foam fire extinguishers. Surfactants aid in lowering the foam’s surface tension, which makes it easier for it to spread over the burning liquid.

How to Use Foam Fire Extinguishers?

Using a foam fire extinguisher is a very simple process. Just follow these steps:

  • Pull the safety pin from the extinguisher to activate it.
  • Point the nozzle or hose at the fire’s origin.
  • Stand at a safe distance, around 6 to 8 feet away.
  • Squeeze or open the handle to discharge the foam.
  • Sweep the nozzle or hose from side to side, covering the fire area thoroughly.
  • Continue applying foam until the fire is completely extinguished.
  • After extinguishing the fire, watch for any signs of re-ignition.
  • If the fire reignites or becomes uncontrollable, evacuate the area and call emergency services.
  • Remember to read and follow the instructions provided on the extinguisher and receive proper training. 

Can Foam Fire Extinguishers Also Be Used for Emergency Situations?

Foam fire extinguishers are effective for dousing flammable liquid fires, but can they be used for emergency situations? While foam extinguishers are versatile and suitable for various fire classes, it’s important to note that they may not be ideal for all emergencies. In certain cases, such as electrical fires or fires involving sensitive equipment, co2 fire extinguishers for emergency may be more appropriate as they do not leave any residue and prevent further damage. Each type of fire extinguisher serves a specific purpose, so it’s crucial to use the right one for each emergency situation.

Precaution to Maintain For Foam Extinguishers 

To ensure the effectiveness and reliability of foam fire extinguishers, follow these important maintenance precautions:

Regular InspectionsConduct routine visual inspections to check for any signs of damage, corrosion, or leakage. Ensure the pressure gauge is within the recommended range.
Proper StorageStore foam fire extinguishers in a designated location away from heat sources or direct sunlight. Follow manufacturer guidelines for temperature and humidity limits.
Avoid FreezingFoam fire extinguishers can freeze in cold temperatures, causing damage. Protect them from freezing by storing them in heated areas or using specialized antifreeze agents.
Maintenance ScheduleAdhere to a regular maintenance schedule, including professional servicing and testing, as recommended by the manufacturer or local regulations.
Training and EducationProvide proper training to individuals on how to use foam fire extinguishers effectively and safely. Educate them on the types of fires suitable for foam extinguishers.
Recharging and RefillingAfter use or during inspections, ensure foam fire extinguishers are recharged or refilled promptly by qualified personnel to maintain their operational readiness.
AccessibilityEnsure that foam fire extinguishers are easily accessible, properly labeled, and located in areas where potential fire hazards are present. Make sure they are not blocked or obstructed.


Foam fire extinguishers are indispensable tools in fire safety, specifically designed to combat fires fueled by flammable liquids. Whether in residential, commercial, or industrial settings, foam fire extinguishers play a vital role in protecting lives and property.

So, it is important to understand their proper usage, follow safety guidelines, and regularly maintain them to ensure their readiness in case of emergencies.

By having foam fire extinguishers readily available and being knowledgeable about their applications, we can contribute to a safer environment and enhance fire safety preparedness.