What is a fire suppression system and how does it work?

A fire suppression system is an integral part of any fire protection infrastructure. ‘Fire suppression’ is a collective term for any engineering group of units that are designed to put out a fire. This can be achieved by applying an extinguishing substance such as water, foam or chemical compounds. This article explores the range of applications within a fire suppression strategy, so site teams and building owners can begin to comply with fire safety regulations and give peace of mind to building occupants and tenants alike.

How does a fire suppression system work?

A fire suppression system will have built-in components to detect fires as early as possible. These components will first identify the presence of flames and smoke. The suppression system will then initiate an alarm, so the blaze can be subdued before it has the chance to spread. A fire suppression system can be considered an ‘active’ fire protection method because the system is triggered in response to the presence of fire. As will be explored further in this article, a fire suppression system also contains a range of components that ‘actively’ work to extinguish flames and smoke.

What is the difference between a fire sprinkler and a fire suppression system?

Both fire suppression systems and sprinkler systems can control or extinguish fires and are activated when detecting heat or smoke. A fire suppression system, however, doesn’t use water as it can be ineffective in certain types of fires. For example, a facility that uses combustible gas or oil, for instance, would not benefit from using water as a fire suppressing agent. For this reason, fire suppression systems are more common in industrial environments than traditional water sprinkler systems.

Why use an automatic fire suppression system?

Just like a traditional system, an automatic fire suppression system will consist of an element that detects heat and smoke and a suppression agent container. There will also often be a manual activation system that acts as a failsafe in the case that the automatic system isn’t triggered.

The main benefit of an automatic fire suppression system is that they eliminate the need for human activation or intervention. Not only does this reduce the risk to occupants’ safety, but it is also ideal for extinguishing fires in remote or less accessible areas of a building or estate.

Furthermore, automatic fire suppression systems are a particularly worthy investment for industries and companies containing flammable materials or high-value goods. This type of preventative measure could be looked upon favourably by insurance providers, who may reward business owners and landlords with lower premium rates for taking this type of precaution.

When is a fire suppression system required?

Fire suppression systems should be installed in buildings where a sprinkler system may not be the most effective method of fire protection. These can include rooms that contain a large amount of electrical equipment, irreplaceable assets or perishable items that could be susceptible to water damage.

Although there are no legal installation requirements for fire suppression systems, property owners, be they commercial or residential, are responsible for arranging experts to conduct fire risk assessments. This assessment, whether conducted internally or externally, may reveal the need for a fire suppression system. Further information can be found in our article on who exactly is responsible for fire safety legislation.

When identifying the best option for your specific needs, it’s advisable to know how both active and passive fire protection systems work in tandem to extinguish flames. This is vital for risk management, reducing the risk of structural damage as well as safeguarding a building’s occupants.

What are the different types of fire suppression?

Broadly speaking, there are five main types of fire suppression systems – all of which have unique properties and benefits based on the respective space in need of protection:

Gas systems

Gas suppression systems store fire-suppressing liquids, which are pressurised with nitrogen. These liquids contain a chemical agent called FM200, which is quickly released to immediately suppress flames. Since these systems don’t use any water, they’re particularly beneficial for rooms with large amounts of electrical equipment such as switchboards or server rooms. The gaseous agent is initially condensed in liquid form and stored in compact cylinders, making these systems easy to transport and store.

Wet chemical foam systems for kitchens

Wet chemical foam systems are specifically designed for suppressing fires in kitchens. These kitchen fire suppression systems work by quickly emitting a water-based chemical foam agent directly into a small, localised area. They are usually placed under the canopies of cookers and are activated by either a manual switch or a heat link (a link attached to a wire that breaks when exposed to heat, triggering the foam release valve).

Water mist systems

Water mist systems pose a viable fire suppression solution for spaces that cannot be exposed to large amounts of water. They work by producing droplets that are much smaller than conventional sprinkler systems. This creates a layer of steam that starves fires of oxygen, quickly reducing the temperature of the affected area. Since they use much less water than traditional sprinklers, they can to some extent be considered a more sustainable fire suppression method. We explore water mist systems in more detail in our article on emerging fire protection technologies.

Foam deluge systems

One of the biggest challenges in fire suppression is effectively safeguarding areas that contain flammable liquids. Foam deluge systems are the most effective means of controlling the spread of these environments. For this reason, they are commonly installed in refineries, aircraft hangers and industrial warehouses. A fire in these types of environments can accelerate tremendously quickly. Therefore, foam deluge systems are designed for the quick widespread application of suppressive materials.

Foam deluge systems use a mixture of foam and water to quickly control burning flammable liquids, cooling the surface area. The consistency of the foam causes a thick blanket to starve fires of oxygen and inhibit the release of flammable gases, effectively smothering the blaze. In this sense, they are not unlike conventional fire extinguishers.

Pneumatic heat detection tubes

Pneumatic heat detection tubes are designed in a way that makes them very similar to fire extinguishers. Therefore, they can be considered the most compact and mobile fire suppression system. These tubes have two primary components: a pipe and a valve. The pipe is installed around the potential source of fire; when it reaches a certain temperature it emits a suppressive agent directly onto the flames via the valve.

Pneumatic heat detection tubes tackle fires in their beginning stages, located in small areas with little room for manoeuvre. Therefore, they are ideal for tackling fires in cabinets and cupboards, as well as boats and vehicles. This does mean, however, that they are unsuitable for suppressing large fires and therefore are not recommended for rooms or areas with a high ceiling.

Which industries commonly use fire suppression systems?

While all industries use fire suppression systems to ensure safer work environments and to reduce property damage, certain sectors have specific requirements which make it even more of a priority to maintain a fully compliant fire suppression system.

• Industrial and manufacturing – This article has made multiple references to the presence of highly flammable materials in industrial settings, but it’s also worth mentioning that industrial and manufacturing plants also contain large amounts of raw materials. Therefore, one of the biggest risks of fire (excluding personal safety) is the potential disruption to supply chains, making a fire suppression system a critical investment.
• Warehousing and storage – Storage facilities will usually make the most of available space, providing that it complies with workplace health and safety regulations. A fire suppression system would effectively manage the risk of having large amounts of potentially flammable goods in close proximity, and provide the amount of coverage needed to protect a large commercial space.
• Data centres and server rooms – After power supply issues, fires are the second most common cause for data centre outages. They also have an average downtime of over 24 hours, and for the many businesses and organisations relying on data centers for their activities the impact can be catastrophic. Data centres and server rooms also contain a large amount of electronic equipment that is highly sensitive to changes in temperature. For both of these reasons, a fire suppression system is an imperative investment.

We hope that this article has helped you gain a basic grounding in the purpose, function and requirements of a fire suppression system. Interested in finding out more about how fire suppression works? If so, take a look at a recent article where we explain the difference between fire protection, prevention and suppression.

CLM Fireproofing are the UK’s leading passive fire protection specialists. Our team of FIRAS-accredited experts offer a wide range of services for residential and commercial buildings, including fire compartmentation and intumescent fireproofing. For expert advice and help developing a fully-compliant fire protection strategy, contact CLM Fireproofing today.