Foam Fire Extinguishers

by Curtis Worthington

Foam Fire Extinguishers: A Guide

There are many ways to prepare your home or business should a fire break out, and one of the easiest ways to do this is to ensure you have fire extinguishers on the premises at all times.


With multiple extinguishers available to help you out with a whole manner of different types of fires, it’s always important to know which ones are useful to you, and how to best use them should you need them.


In the next instalment of our fire extinguisher guides, we’re showcasing one of the most commonly used fire extinguishers around – foam fire extinguishers.


What is a Foam Fire Extinguisher?


While at work or in a number of other buildings, if a fire breaks out, it’s highly likely that the type of extinguisher you’ll encounter will be a foam one.


Generally favoured for fires that that involve flammable solids and liquids, this is what makes them popular for the majority of premises, due to them being great, general use fire extinguishers.


However, they aren’t always known as foam fire extinguishers. So, if you come across ones named AFFF foam fire extinguishers or , be aware that these are all variations of the same type of extinguisher.


When to use and not to use a Foam Fire Extinguisher


A great multi-purpose extinguisher, these can be used on a lot of different fires – which is what makes them so popular.


Therefore, if you own premises that could encounter any of the following fires, or you happen to encounter any of the following, then a foam extinguisher is sure to help you out.


  • Fires that involve flammable solids such a paper, wood and textiles, which are known as Class A fires
  • Ones that involve some flammable liquids such as petrol, diesel and paint, which are known as Class B fires
  • Fires involving some electrical appliances, but only if the extinguisher has passed a 35kv conductivity test


As foam extinguishers aren’t explicitly designed to be used on electrical fires, the 35kv conductivity test is designed to act as an additional safety measure. This is intended to safeguard those that may accidently use of these extinguishers on an electrical fire, which can bring risks such as the possibility of an electric shock to the user.


This is why it’s strongly recommend that you only use a CO2 extinguisher on electrical fires. However, if you do have a foam extinguisher to hand and there is a risk of an electrical fire, the 35kv conductivity test is highly recommend.



How to Identify a Foam Fire Extinguisher


Identifying a foam fire extinguisher is pretty easy as this can be done thanks to the label citing foam, and you’ll often find an extinguisher ID sign fixed nearby also stating ‘Foam Extinguisher’.


However, in the case of a fire, you may not have enough time to locate these signs and identifying which extinguisher is which – hence why you can get foam extinguishers safeguarded in the event of an electrical fire.


Because of this, the most important thing to remember is that foam extinguishers can be instantly identified thanks to the cream coloured labels.


In terms of size, the most frequently used canister size of a foam extinguisher is six litres, however you can also find them in two, three and nine litre variations.


How Foam Fire Extinguishers Work


Learning the ins and outs of various fire extinguishers is the best way to equip yourself should a fire break out. With foam extinguishers being the most common, arming yourself with the knowledge on how to use them is paramount.


There are actually two different ways that a foam fire extinguisher works, these are:


  • As the extinguishers are mainly water-based, they have the same cooling effect as water extinguishers, which work by putting the fire out by reducing the temperature
  • The second way in which these extinguishers work is through foam creating a barrier between the fire and the air required to enable the fire to burn



How to use a Foam Fire Extinguisher


Although it’s always extremely helpful to know the ins and outs of a particular fire extinguisher, such as how to identify one and how they individually help to extinguish fires, the most pivotal bit of information is knowing how to use one correctly.


Depending on the type of fire you’re tackling these extinguishers will need to be used differently each time. However, in the first instance you’ll always need to remove the safety pin in order to break the anti-tamper seal and stand away from the fire.


Flammable Liquid Fires:


  • Do not spray the extinguisher directly at the fire as this could spread the fire on to nearby surfaces
  • If the liquid fire is contained, then you should point the extinguisher towards the inside edge of the container
  • For liquid fires that aren’t contained you should spray with a gentle, sweeping movement across the top of the fire, or against an adjacent surface
  • By doing this, the foam will drop down and settle on top of the burning liquid to extinguish the fire


Flammable Solid Fires:


  • When tackling this type of fire aim the extinguisher towards the base
  • Following this, keep the extinguisher moving backwards and forwards across the flames while you spray



How Long Does a Foam Fire Extinguisher Last?


Although they won’t last forever, fire extinguishers don’t tend to have an expiration date. However, you should still check them regularly to ensure they haven’t been damaged or have been tampered with. They should be serviced annually by a competent service company



The Pros and Cons of a Foam Fire Extinguisher


Despite being the most commonly used fire extinguisher, they come with their pros and cons just like any other, which are listed below:




  • On the whole they’re safe if accidently used on electrical fires, but is still advised against
  • They’re designed to prevent the re-ignition of fires
  • These are also much lighter in weight than equivalent water extinguishers



The units , if sited externally will require an anti-freeze additive, as at zero degrees they will freeze



Who Should Have a Foam Fire Extinguisher?


As one of the most commonly used fire extinguishers these can be used on a lot of different fires, which means they can be helpful to have in a whole manner of environments, especially those that tend to have multiple fire risk factors. These can include:


  • Offices
  • Hotels
  • Garages
  • Warehouses
  • Factories


Regardless of your premises, it’s always handy and highly recommend to have a foam extinguisher or two on site, as they can be used in a number of instances. Pairing one of these up with a CO2 fire extinguisher is also beneficial as these can help tackle electrical fires.


In Synopsis


Although these tips are only the basics in regards to foam fire extinguishers, as they’re an extinguisher you’re sure to find yourself coming across due to their practicality and ability to extinguish a wide range of fires, they should be enough to help you out should a fire break out on your premises.

If you happen to own premises yourself, you’ll now know exactly what type of extinguishers you should have on your premises should the unthinkable happen.

If you do happen to be the owner of your own premises, or if you’re currently kitting one out, you can find a whole range of foam fire extinguishers to meet your needs right here.


However, for those of you that aren’t too sure on what type of extinguishers you need for your business, or if you’re looking for a little bit of help and guidance, then you can contact us on either 0800 316 1469 or 0330 058 0631.