What you Need to know When Buying Fire Extinguishers
If you are replacing existing fire extinguishers it is easy to choose the correct fire extinguishers, as long as you are certain that nothing has changed in terms of fire risk since the last visit by a service engineer. Just ensure that you purchase extinguishers with the same type of extinguishing agent (powder, AFFF foam, CO2, water etc) as are currently installed and that the rating of the new units at least matches the rating of the existing extinguishers. The physical size of the extinguishers does not matter, as long as the rating is met.
If you are purchasing extinguishers for new premises or the building or its use has been altered, we would recommend that you ask us to carry out a site survey. We will send one of our fire extinguisher service engineers to carry out the site survey and to recommend types and locations of fire extinguishers required.
Cartridge Operated or Stored Pressure?
There are two types of portable fire extinguisher: cartridge operated and stored pressure. While most extinguishers in use are stored pressure, it is important to decide whether you require cartridge operated units or not before making your purchase.
Cartridge operated extinguishers are made up out of a cylinder filled with the extinguishant (water, foam, powder, etc.) and a gas cartridge containing highly pressurised CO2. The cylinder itself is not pressurised while not in use and the pressure is only released from the cartridge once the handle is squeezed and pierces the cartridge, which will then drive the extinguishant out of the cylinder via the hose.
Stored pressure extinguishers on the other hand consist of a cylinder containing the extinguishing agent (water, powder, foam etc.) and are permanently pressurised with either dry air or oxygen-free nitrogen. When the extinguisher is activated by squeezing the handle, the valve inside releases and the pressure pushes the extinguishing agent out through the hose.
Cartridge operated extinguisher have an advantage over their stored pressure counterparts in that their outer cylinder can be pierced without the extinguisher exploding. Should a stored pressure extinguisher cylinder be pierced it would release the pressure explosively. If the environment you wish to install fire extinguishers into is harsh, i.e. there is a real possibility that the extinguishers will suffer knocks and bangs, etc. then it may be prudent to invest in cartridge operated units. If however you are installing extinguishers in a regular environment such as an office building then stored pressure would be perfectly adequate for your needs.
How Many Extinguishers Do I Need?
The basic requirement for fire extinguishers (Class A fire risks) of a building is calculated by multiplying the area of a building's floor space in square metres by 0.065. For example, if a single floor building is 20m x 10m you would have a floor area of 200 square metres. Multiply this by 0.065 and you arrive at the number 13. You now know that the fire extinguisher provision has to be 13A or higher. However, the actual minimum Class A provision per storey, according to BS 5306-8:2012, is 2x A-rated extinguishers with a combined rating of at least 26A. Once you have determined what rating you require you can select your extinguishers. If you are required to provide e.g. 26A, you would have to pick extinguishers with a total Class A rating of 26A or higher. An extinguishers ratings are advertised with the extinguishers and vary from brand to brand.
Example: if your building is 600 square metres your minimum requirement for Class A fire extinguishers would be 39A (600 multiplied with 0.065 = 39). This could for example be covered by two 6ltr water fire extinguishers (with additives) with 21A rating each.
On top of this you would need to account for any specific risks that your building contains by considering a few questions (risk assessment):
- Is there an area of your building that is used to store flammable liquids (for this you would need a Class B rated extinguisher to cover the risk)? A building which contains for example 50 litres of flammable liquid (e.g. Diesel), would require a Class B rating of more than 50B. You could in such a case consider foam fire extinguishers instead of the above mentioned water extinguishers, as foam extinguishers cover both Class A and Class B risks. For example 2x 6l foam extinguishers might give you a total rating of 42A and 288B (depends from the make of the extinguisher)
- Where is the mains power distribution board located you may want to include a CO2 extinguisher, although foam extinguishers, if tested to 35kV, and dry water mist extinguishers might also be used
- Does the building have a kitchen area and if so what appliances are located there? (for electrical appliances you may want to include a dry water mist or CO2 extinguisher and if you have a deep fat fryer you need to install a Class F wet chemical extinguisher or a dry water mist extinguisher)
Other Considerations when Provisiong Fire Extinguishers
Extinguishers located on the same floor of a building or across all floors if it is a single occupancy should all have a similar method of operation and should be of a similar design and standard. Therefore, EN3 extinguishers, which are red with a colour bar indicating the type of extinguisher, should not be mixed with older BS 5423 extinguishers, where the whole body is coloured to indicate the type of extinguisher). Extinguishers located on different floors should be located in a similar place to make it easier to locate them in an emergency.
Distance of Travel
The user should not have to travel more than 30m for Class A and C risks and 10m for Class B and F risks. Extinguishers should be located on escape routes, near to room exits, next to final exits, in corridors etc.
The Regulatory Reform Order 2005 states that a person in control of a building must carry out a fire risk assessment, part of which is the provisioning of fire-fighting equipment. The person in control of the building might want to outsource this to a trained individual who can perform the risk assessment and indicate the correct provisioning for the building. Safelincs is happy to carry out extinguisher site surveys which are free of charge if you order the required fire extinguishers from us.
The Buying Process
When you place an order for fire extinguishers you will have various options available which will enable you to purchase optional extras such as signs, stands and certification and wall hanging.
Option 1 - Extinguisher Only
If you do not require the extinguishers to be wall hung or certified on-site you should choose the "Fire Extinguisher Option" (OPTION 1). This will add the extinguisher to the basket without on-site certification or wall hanging and then allow you to choose optional identification signs and extinguishers stands.
Please note: extinguishers for business premises should be certified on-site in accordance with BS5306.
Option 2 - Extinguisher with On-Site Certification
If you require the extinguishers to be certified on-site or would like you extinguishers to be wall hung you should choose the "Extinguisher With On-Site Certification Option" (OPTION 2). This will add the extinguisher to the basket with on-site certification and allow you to choose optional wall hanging or fire extinguisher stands and add additional identification signs.
After you have purchsed you extinguishers we will deliver them to you and send one of our BAFE registered engineers to commission them on-site. This includes checking that the extinguishers were not damaged in transit, that they have been correctly installed and certifying that you have adequate extinguisher cover.
If you choose optional wall hanging the engineer will fit wall brackets and any signs that you have purchased.
Do I Need Identification Signs?
Under the EN 3 standard, the front label of a fire extinguisher now carries all the necessary information regarding what types of fire it can be used on and the procedure for actually using it. This means that the extinguisher itself is a fire extinguisher sign and a separate sign, in accordance to EN 3, might no longer be required. However, the official Fire Risk Assessment Guides state that suitable signs may be required to indicate the location of extinguishers and the latest British Standard for the provision of fire extinguishers (BS 5306-8:2012) states that: 'The position and type of a fire extinguisher should be indicated on a sign so that, if the extinguisher is removed, this can be identified during a safety inspection, and a replacement ordered'.
What Needs to be Considered?
While additional fire extinguisher signs may formally not be required in your building, there are compelling reasons to include signs in your provisioning. Imagine that you are trapped in a building during a fire, the rooms and corridors are slowly filling with smoke and reducing the available light and visibility. If your extinguisher, correctly installed on its bracket, is on the other side of a room full of desks and chairs, it is highly likely that you won't be able to see where it is. You may think that you will be ok as you have had fire drills and training and you know where the extinguishers are located. But in an emergency it is all too easy to get disoriented, for the thick choking smoke to obscure your vision and for panic to set in. In a situation such as this you will be thankful that you included some photoluminescent fire extinguisher signs and had them installed at eye level. They are cost effective, require no power source (light is soaked up during the day and discharged when it is dark).
A sign must be installed if the extinguisher itself is not directly visible. In modern offices where everyone has their own cubicle it would be very difficult to locate the nearest fire extinguisher in an emergency. In this kind of installation it would be necessary to install some fire extinguisher location signs that are visible from anywhere in the room. Panoramic photoluminescent fire equipment location signs are ideal as they are viewable from every angle and are visible in low light.
Reviewed: 18/07/2017 (doc:22 V1.0). Our articles are reviewed regularly. However, any changes made to standards or legislation following the review date will not have been considered. Please note that we provide abridged, easy-to-understand guidance. To make detailed decisions about your fire safety provisions, you might require further advice or need to consult the full standards and legislation.