What Are Foam Fire Extinguishers Used For?

One of the most common fire extinguisher types, foam extinguishers can be found in plenty of buildings up and down the country in the UK. But do you know what type of fire they should be used on or how to activate one?

This month at Fire Safety Equipment, we’ll take you through everything you need to know about foam fire extinguishers, including answering the questions we just posed, along with when not to use a foam extinguisher, when to have one replaced and much more.

Having the right extinguishers at hand can save lives, but they’re no good if you can’t identify the right one. You can find a full range of fire extinguishers in our store, but carry on reading if you want more details on foam fire extinguishers.

What is a foam fire extinguisher?

A foam fire extinguisher is a specific type of fire safety equipment containing a special foam that you can use to put out fires. The foam works in two ways; firstly through water, of which it is primarily made, which allows the user to extinguish a fire and lower the temperature of the materials acting as a fuel source. 

The second way in which they quell a fire is through the aqueous film-forming foam (the reason they’re sometimes known as AFFF extinguishers). This special foam layer helps to smother the flames, preventing any flammable vapours from escaping and causing the fire to reignite. This can also separate the flames that have taken hold from the liquid itself, such as a paint or petrol spill that has been ignited.

Foam fire extinguishers can be identified by a cream label and the word ‘Foam’ should be printed on the body of the unit itself.

What should you use a foam fire extinguisher for?

As we alluded to in the previous section, foam fire extinguishers can be used for fires involving flammable liquids such as paint, petrol and diesel (known as Class B fires). The foam helps to create a barrier without dispersing too much of the liquid that is acting as the fuel.

Due to the water content, a foam fire extinguisher can also be used on Class A fires. These are fires where an organic material – usually paper, textiles or wood in composition – has caught fire. This is because the foam can soak the material and lower the temperature to put out the flames.

How to use a foam fire extinguisher

There are several steps to follow for using a foam fire extinguisher, but your approach should be different depending on whether it’s a Class A or Class B fire. In both instances, you need to stand well back from the fire and pull the safety pin at the top of the unit. This will break the anti-tamper seal and allow you to use the handle.

For Class A fires:

• Aim the nozzle at the base of the fire
• Squeeze the handle to release the foam extinguishant
• Carefully sweep back and forth across the flames

For Class B fires:

• Aim the nozzle at the inside edge of the container if this is where it is located
• Where the liquid is spilt, aim the foam over the fire
• Avoid spreading the flames by not directing the foam at the fire itself
• The foam should then drift down onto the flames rather than splashing

When should you not use a foam fire extinguisher?

There are two main fire types you should never use a foam fire extinguisher for. The first is a Class C fire involving flammable gases, such as butane and methane. This is because the foam will prove ineffective against gases.

The second fire type you shouldn’t tackle with a foam extinguisher is Class F kitchen fires. This is because they involve oils, grease and fats that can be splashed if you use a foam unit. That splash can then spread the fire further or cause an injury.

How to maintain a foam fire extinguisher

Maintaining any fire extinguisher requires vigilance on your part, along with annual basic servicing, plus extended servicing every five years for a foam or water-based extinguisher. 

Your own visual inspection should be carried out monthly, checking that your foam fire extinguishers have not been damaged and that the anti-tamper seal is still in place. If the seal has been removed, you may need to think about replacing or recharging the unit.

How often should you replace a foam fire extinguisher?

Foam fire extinguishers, like all extinguishers, will gradually deteriorate over a long period. But while there is no fixed expiry date you need to be aware of, you can find a manufactured date on the extinguisher itself to guide you. It’s recommended that you replace your foam extinguishers every 10 years, or sooner if they have been damaged or discharged.

What type of business needs foam fire extinguishers?

Since foam fire extinguishers cover several different fire types, they’re a good extinguisher type for a number of different businesses across various sectors. Due to the mixture of potential fire hazards, you might need to consider foam extinguishers if you own or manage the following:

• An office – where paper and waste can accumulate
• A warehouse – where stock and spilt liquid fuels are present
• A hotel – where textiles are present in large quantities
• A mechanics garage – where vehicle fuel and paint may be present
• A factory – where packaging and materials are stockpiled

If you also have the risk of an electrical fire in these settings, you might want to pair a CO2 fire extinguisher with a foam fire extinguisher for better coverage of multiple risks — read more about CO2 extinguishers in our recent post.

Here at Fire Safety Equipment, we stock a range of foam fire extinguisher sizes and types – including alcohol-resistant foam extinguishers – helping you to protect lives and your business. 

You can order all your essential equipment from us online, avoiding the need to shop around and wait for multiple separate orders. Contact us for more advice today or purchase foam fire extinguishers and all your other fire safety equipment with us online and get fast, free delivery within the UK.