It is one of the most common questions that business owners and facilities managers ask when they are getting to grips with their fire safety obligations.
And it is a question that does not always have a straightforward answer, because the number, type, and location of fire extinguishers required for any given premises depends on a range of factors that are specific to that premises and its occupancy.
This article explains who is responsible for making that determination, what guidance they should use, and what the key factors are that influence the decision.
Who is Responsible for Deciding?
The short answer is that the Responsible Person is responsible.
Under Article 9 of the Regulatory Reform (Fire Safety) Order 2005 (SI 2005/1541), the Responsible Person is required to carry out a suitable and sufficient fire risk assessment that identifies the fire hazards present in the premises and evaluates the risks they pose to occupants.
Under Article 13 of the RRO, the Responsible Person is required to ensure that the premises is equipped with appropriate firefighting equipment, and that any non-automatic firefighting equipment is accessible, simple to use, and indicated by signs.
The RRO does not specify exactly how many fire extinguishers are required, or precisely where they should be located.
It requires that the firefighting equipment provided is appropriate for the risks present, and that the Responsible Person can demonstrate that a proper assessment has been carried out to determine what is needed.
In practice, the determination of what constitutes appropriate firefighting equipment for a specific premises is made by the fire risk assessor, who will consider the specific hazards, risks, and characteristics of the building and its occupancy and make recommendations based on the relevant guidance.
What Guidance Do Assessors Use?
The primary guidance document used by fire risk assessors and fire extinguisher engineers in determining the appropriate provision of portable fire extinguishers is BS 5306-8:2012, Fire Extinguishing Installations and Equipment on Premises, Selection and Positioning of Portable Fire Extinguishers.
BS 5306-8 provides detailed guidance on the selection of extinguishers of the appropriate type for the hazards present, the number of extinguishers required for a given floor area, and the positioning of extinguishers to ensure that they are accessible and usable in the event of a fire.
The standard is widely regarded as the authoritative reference for fire extinguisher provision in non-domestic premises in the United Kingdom, and fire risk assessors will typically base their recommendations on its requirements.
Sector-specific guidance documents published by the Department for Levelling Up, Housing and Communities and the National Fire Chiefs Council also provide guidance on firefighting equipment provision for specific types of premises, including offices, shops, factories, warehouses, educational establishments, and healthcare premises.
The Classes of Fire
Before examining the specific requirements of BS 5306-8, it is helpful to understand the classification of fires, as this is the foundation of the extinguisher selection process.
Fires are classified according to the type of fuel involved, using a system of letter classifications defined in BS EN 2.
Class A fires involve solid materials, typically organic in nature, such as wood, paper, textiles, and plastics.
Class B fires involve flammable liquids, such as petrol, diesel, oils, paints, and solvents.
Class C fires involve flammable gases, such as propane, butane, and natural gas.
Class D fires involve combustible metals, such as magnesium, aluminium, and titanium.
Class F fires involve cooking oils and fats, such as those used in commercial deep fat fryers.
Electrical fires, sometimes referred to as Class E fires in other countries, are not a separate classification in the UK system, but electrical equipment is a common ignition source and the presence of electrical equipment influences the selection of extinguisher types.
The type or types of fire extinguisher required for a premises depends on the classes of fire that could occur, which in turn depends on the materials present and the activities carried out.
Types of Fire Extinguisher
There are several types of portable fire extinguisher available, each suited to different classes of fire.
Water extinguishers are suitable for Class A fires involving solid combustible materials.
They are the most common type of extinguisher found in commercial premises and are effective against fires in wood, paper, textiles, and similar materials.
Standard water extinguishers should not be used on electrical equipment, on Class B fires involving flammable liquids, or on Class F fires involving cooking oils.
Water mist extinguishers use a fine spray of microscopic water droplets and are effective against a wider range of fire classes, including Class A, Class B, and Class F fires.
They are also safer for use near electrical equipment than standard water extinguishers, as the fine mist does not conduct electricity in the same way as a jet of water.
Water mist extinguishers are increasingly specified in healthcare environments and other premises where a versatile, low-risk extinguisher is desirable.
Foam extinguishers are suitable for Class A and Class B fires.
They are commonly used in premises where flammable liquids are present, such as garages, paint stores, and laboratories.
Carbon dioxide extinguishers, commonly referred to as CO2 extinguishers, are primarily intended for use on fires involving electrical equipment and on Class B fires.
They leave no residue and are therefore particularly suitable for use in areas containing sensitive electronic equipment such as server rooms and data centres.
CO2 extinguishers are not effective against Class A fires and should not be used in confined spaces without adequate ventilation, as the carbon dioxide gas they discharge can displace oxygen and create a risk of asphyxiation.
Dry powder extinguishers are effective against Class A, Class B, and Class C fires, and can also be used on fires involving electrical equipment.
However, they produce a cloud of powder that can significantly impair visibility, contaminate food and sensitive equipment, and create a respiratory hazard for occupants.
For these reasons, dry powder extinguishers are generally not recommended for use in occupied buildings, and are more commonly specified for outdoor use and for specific industrial applications.
Wet chemical extinguishers are specifically designed for Class F fires involving cooking oils and fats, and are the recommended type for commercial kitchens equipped with deep fat fryers.
They should be provided in addition to, rather than instead of, the extinguishers provided for other fire classes in the rest of the premises.
How Many Extinguishers Are Required?
BS 5306-8 sets out the basic provision of fire extinguishers for Class A risks using a risk-based approach.
The standard divides premises into three risk categories, lower risk, normal risk, and higher risk, based on the nature of the occupancy, the fire load present, and the likelihood of a fire starting.
Lower risk premises are those with limited quantities of combustible material, where the risk of fire starting is low and the potential consequences are limited.
Normal risk premises are those that represent the majority of commercial and public buildings, where there is a moderate fire load and a moderate risk of fire starting.
Higher risk premises are those where there is a significant fire load, where flammable materials are present, or where the activities carried out create an elevated risk of fire.
For normal risk premises, BS 5306-8 recommends a minimum of one water or foam extinguisher with a minimum rating of 13A for every 200 square metres of floor area, with a minimum of two extinguishers per floor regardless of the floor area.
This means that a small office of 100 square metres still requires a minimum of two extinguishers, even though the floor area would suggest that one might be sufficient.
For higher risk premises, the provision should be increased accordingly, with extinguishers rated at a higher level and provided at a greater density.
The standard also requires that no occupant should have to travel more than 30 metres to reach a fire extinguisher, which influences the positioning of extinguishers within larger premises.
In addition to the basic Class A provision, extinguishers of the appropriate type must be provided for any additional fire classes present in the premises.
A premises with a server room will need CO2 extinguishers for the electrical equipment.
A premises with a commercial kitchen will need wet chemical extinguishers for the cooking equipment.
A premises where flammable liquids are used or stored will need foam or powder extinguishers for the Class B risk.
And the provision for each additional hazard area must be assessed separately, in addition to the basic provision for the general Class A risk throughout the premises.
Where Should Extinguishers Be Located?
The positioning of fire extinguishers is as important as the number provided.
An extinguisher that is difficult to find, inaccessible, or positioned in a location where it cannot safely be used is of little value in an emergency.
BS 5306-8 recommends that extinguishers are positioned on escape routes, typically near exits and at the foot or head of staircases, so that they are accessible to occupants who are moving towards safety rather than requiring them to move towards the fire to access an extinguisher.
They should be positioned at consistent locations throughout the building, so that staff and other regular occupants can locate them quickly without needing to search.
They should be mounted on brackets or stands at a height that makes them accessible to all users, with the handle of the extinguisher at approximately one metre above the floor.
They should be clearly identified by appropriate signage, as required by Article 13 of the RRO.
And they should not be positioned in locations where they are likely to be obstructed, damaged, or subject to extreme temperatures that could affect their performance.
Maintenance and Servicing
Providing an appropriate number of correctly specified and positioned fire extinguishers is not the end of the Responsible Person’s obligation.
Under Article 17 of the RRO, fire extinguishers must be maintained in an efficient state, in efficient working order, and in good repair.
BS 5306-3:2017, Commissioning and Maintenance of Portable Fire Extinguishers, sets out the requirements for the inspection, servicing, and maintenance of portable fire extinguishers.
Extinguishers should be subject to a basic annual service inspection by a competent person, and to extended service and overhaul at the intervals specified in BS 5306-3, which vary depending on the type of extinguisher.
Monthly visual checks should also be carried out by a competent person within the organisation, confirming that each extinguisher is in its correct position, has not been discharged or damaged, and that the pressure gauge, where fitted, indicates that the extinguisher is correctly charged.
Any extinguisher that has been discharged, even partially, must be recharged or replaced before being returned to service.
And any extinguisher that is found to be damaged, corroded, or otherwise defective must be removed from service immediately and replaced.
Should Staff Be Trained to Use Extinguishers?
This is a question that generates considerable debate, and it is worth addressing directly.
The primary purpose of portable fire extinguishers in most premises is not to enable occupants to fight fires.
It is to enable a small, incipient fire to be tackled in its very early stages, before it has developed to a point where it presents a serious risk to life or property, and only where it is safe to do so.
No occupant should ever put themselves at risk by attempting to use an extinguisher on a fire that has already developed significantly, that is spreading rapidly, or that blocks their means of escape.
The priority in any fire is always to raise the alarm and evacuate the building.
With that important caveat clearly understood, there is value in ensuring that staff are aware of the types of extinguisher available in their workplace, the classes of fire for which each type is appropriate, and the basic operating procedure for the extinguishers provided.
Under Article 21 of the RRO, the Responsible Person is required to ensure that employees are provided with adequate fire safety training, which should include information about the firefighting equipment available and how it should be used.
Practical fire extinguisher training, using training extinguishers or controlled fire scenarios, is available from a range of fire safety training providers and is a worthwhile investment for most commercial premises.
What About Fire Blankets and Hose Reels?
Fire blankets and hose reels are additional firefighting equipment that may be appropriate in some premises.
Fire blankets, specified in BS EN 1869:2019, are particularly suitable for use in kitchens, both domestic and commercial, where they can be used to smother small fires involving cooking equipment or to wrap around a person whose clothing has caught fire.
They should be provided in commercial kitchens in addition to wet chemical extinguishers, and their location should be clearly signed.
Hose reels, providing a continuous supply of water from the mains supply, may be appropriate in larger premises where a sustained water supply for firefighting is desirable.
Their installation and maintenance is governed by BS 5306-1:2006, and they should be considered as part of the overall firefighting equipment strategy for larger or higher-risk premises.
We Can Help
At ESI: Fire Safety, we carry out fire risk assessments for all types of commercial and residential premises, providing clear and specific recommendations on the appropriate provision, type, location, and maintenance of fire extinguishers and other firefighting equipment.
Our assessors are experienced in applying BS 5306-8 and other relevant guidance to a wide range of premises types, and can advise on all aspects of firefighting equipment provision including the selection of extinguishers for specialist hazards, the positioning of equipment within complex layouts, and the training of staff in safe and appropriate extinguisher use.
If you are unsure whether your current firefighting equipment provision is adequate, or if you would like a professional assessment of your premises, get in touch with our team today.
Further Reading and Key Legislation:
Regulatory Reform (Fire Safety) Order 2005 (SI 2005/1541): https://www.legislation.gov.uk/uksi/2005/1541/contents/made
BS 5306-8:2012 Selection and Positioning of Portable Fire Extinguishers: https://www.bsigroup.com
BS 5306-3:2017 Commissioning and Maintenance of Portable Fire Extinguishers: https://www.bsigroup.com
BS EN 1869:2019 Fire Blankets: https://www.bsigroup.com
BS EN 2 Classification of Fires: https://www.bsigroup.com
Approved Document B, Fire Safety: https://www.gov.uk/government/publications/fire-safety-approved-document-b
National Fire Chiefs Council fire safety guidance: https://nfcc.org.uk
This post is intended as a general guide. The appropriate provision of fire extinguishers varies significantly depending on the specific characteristics of the premises. Always seek advice from a qualified fire risk assessor or fire extinguisher engineer for guidance specific to your premises and circumstances.
