CONDENSED Aerosol Fire Suppression System

'Aerosol suppression is a remarkable and innovative new technology that is ideal for protecting almost any type of enclosed fire risk - quickly and cost effectively.'

Condensed aerosol fire suppression systems are a unique method of extinguishing a fire inside a room or enclosed area, and they offer many benefits. Condensed aerosol is a dry agent that leaves little residue is non-harmful, non-destructive, and does not require a completely ‘air-tight’ enclosure to be effective.

Aerosol fire suppression is ideal for machinery spaces such as CNC machines, generator rooms, robot cells, electrical switchgear, hazardous storage areas, and many other applications.

Aerosol fire suppression systems extinguish a fire like gaseous suppression agents by ‘flooding’ the volume of the protected area with billions of tiny airborne particles of extinguishing agent. This creates an atmosphere in which fire cannot exist, as the airborne particles prevent the ‘free radicals’ from a fire from burning.

Compared to many suppression systems, they are relatively cheap to install. They do have the disadvantage that there is a fine residue of dust left behind, which could cause damage to sensitive electronic equipment such as server rooms; however, this does need to be balanced with what damage there would be in the room if there were a fire anyway.

As with all suppression systems, there is a dual coincidence (also known as double knock) detection system. This means both detection methods must be activated before the actual suppression system is activated to prevent accidental agent release.

Table of Contents

How do condensed Aerosol Fire Suppression Systems work?

These systems release a cloud of condensed aerosol particles into the protected area. The aerosol interrupts the chemical reactions occurring in the flame, removing heat and inhibiting combustion.

This breaks the process known as the ‘feedback loop of fire‘. This process can be seen in this video of an aerosol generator undergoing fire testing.


What types of fires are condensed aerosol systems suitable for?

Condensed aerosol systems are effective against Class A and B, which include ordinary combustibles, flammable liquids, and electrical fires <75kV.

Aerosol is also effective against Class C fires and has proven effective against lithium-ion battery fires. However, it is critical to consider whether you are exchanging the fire risk for an explosion risk in suppressing fires of this nature.

With fires of this nature, you may suppress the flames, but the flammable gases or vapours (such as electrolyte vapours in the case of batter fires) are uncombusted, uncontrolled – and have the potential then to be ignited suddenly, causing an explosion.

Are condensed aerosol systems environmentally friendly?

Generally, condensed aerosol systems are considered environmentally friendly. The aerosol particles are non-toxic, and many systems use agents that have minimal impact on the ozone layer. However, it’s essential to check the specific formulation of the aerosol agent.

How long does it take for condensed aerosol systems to extinguish a fire?

The time it takes to suppress a fire with condensed aerosol systems can vary based on factors such as the fire’s size, the aerosol’s concentration, and the specific application. Generally, these systems act quickly, often suppressing fires within seconds to minutes.

As with any airborne extinguishing agent, the ‘hold time’ of the extinguishing agent is just as critical as its ability to knock out the flames. When the extinguishing agent is released, the fire is swiftly suppressed. However, the conditions which created the fire (fuel, heat and oxygen) are still present. If the extinguishing agent is removed from the environment and no longer inhibits the flames from occurring, the fire could re-occur.

That’s why aerosol needs an enclosed room/area to operate effectively, even if the room is not fully air-tight. This allows the agent to hold for at least 10 minutes.

If extraction systems are in the protected area, these should be shut off. If there are large ‘leakage’ areas in the protected area, a secondary discharge of condensed aerosol is sometimes required several minutes after the primary discharge to maintain the aerosol concentration in the protected area.

What are the advantages of condensed aerosol fire suppression systems?

Some advantages include rapid and effective fire suppression, reduced damage to protected assets due to the lack of water or foam, compact design, and minimal maintenance requirements.

Are there any limitations to condensed aerosol systems?

While condensed aerosol systems are versatile, they may have limitations in extremely large or open spaces. The concentration of aerosol particles needed to suppress a fire effectively may be challenging to achieve in such environments.

Can condensed aerosol systems be used in sensitive electronic or valuable equipment environments?

Aerosol is best suited to machinery/industrial environments and electrical switchgear applications as it leaves a fine dusty residue. The residue (comprised of potassium salts) is non-corrosive but should be cleaned promptly from sensitive equipment by vacuum cleaning, brushing, or blowing with compressed air, as it is hygroscopic (meaning it attracts moisture from the air).

Thus, the longer it sits, the harder it becomes to clean away.

As such, whilst aerosol is suitable for protecting sensitive equipment, including data centres and server rooms, it is rarely the first choice for these environments. Completely clean agents like inert gas are the optimal solution.

However, if these ‘clean’ agents are not a viable solution, then aerosol is an excellent alternative. ‘Clean agent’ gaseous fire suppression systems are more expensive to install and maintain.

Crucially, the requirement for ‘room integrity‘ on a gaseous suppression system can cause significant builders costs to meet the rigorous requirements of preventing the gaseous agent from escaping from the protected room – rendering gaseous fire suppression impractical.

Ultimately – a fire will be far more damaging to your sensitive equipment than the residue that a condensed aerosol fire suppression system may leave!

What is the lifespan of a condensed aerosol fire suppression system?

If not discharged during their lifetime, the aerosol generators should be replaced after 15 years, and the old generators should be returned to the manufacturer for recycling.

If discharged in a fire, the aerosol generators should be replaced with new units, as they are designed for a single discharge only.

The steel casing that houses the generator can be recycled once discharged.

How is the installation and maintenance of condensed aerosol systems handled?

Trained professionals should perform installation; regular maintenance is crucial to ensure the system’s reliability. Maintenance typically involves periodic checks of the system components and ensuring that the aerosol generators are functional.

Are there any safety considerations for occupants during the discharge of condensed aerosol?

While the aerosol used is generally non-toxic, safety measures should still be taken during the discharge, such as ensuring proper ventilation and following guidelines for evacuation.

Are condensed aerosol systems approved by relevant safety standards?

Yes, reputable condensed aerosol fire suppression systems should comply with industry standards and regulations, such as those set by organizations like NFPA (National Fire Protection Association) and UL (Underwriters Laboratories).

Condensed Aerosol – Safety & Environmental Benefits Summary:

  • Environmentally Responsible, Safe, Long Life:
  • Harmless to humans and animals
  • Harmless to the environment
  • No PFAS “forever chemicals”
  • Harmless to the ozone layer
  • Non global warming
  • Non-toxic (although be aware, not all aerosols are created equal. Test report available).
  • Harmless to equipment & stock
  • It does not deplete oxygen levels
  • Up to 15-year lifespan

Advantages of Using Aerosol, compared to many other extinguishing methods:

  • Operates in a “leaky environment” (Not held in risk space under pressure)
  • Air-tight room not required.
  • BS EN allows for a certain amount of leakage.
  • Room Integrity Test is not required under BS EN standards (although sometimes recommended as part of the initial installation).
  • No loss of oxygen content from the risk area.
  • No pressure relief vents to external walls.
  • No pipes or nozzles clashing with other services.
  • No pressurised bottle storage.
  • No structural or builder works are required.

What 'Standards' are there for Aerosol Fire Suppression Systems:

  • BS EN 15276-1 – Aerosol equipment design & manufacturer.
  • BS EN 15276-2 – Aerosol system design, installation, commissioning & maintenance.
  • NFPA 2010 – Aerosol system design, installation, commissioning & maintenance.
  • ISO 15779: 2011 – Aerosol equipment, system design, commissioning & maintenance.
  • An ageing ISO standard is currently under a major review and re-write.
  • SCP05 FPS K21045 Fire protection Lithium-Ion battery storage.
  • Incorporating NFPA 855 & UL 9540.

Aerosol Fire Suppression Applications:

  1. Packaged generator sets are an ideal application for aerosol fire suppression, where multiple hazards (electrical and mechanical) from the equipment are present. Aerosol fire suppression is compact and lightweight, which allows it to retrofit into these applications.
  2. Electrical power distribution is a common environment in which aerosol fire suppression is used. The HV and LV switchgear rooms are ideal applications for aerosol fire suppression, mainly as these areas are generally not sufficiently sealed for a gaseous fire extinguishing agent to be used. An alternative in some of these areas is to use in-cabinet fire suppression with an agent such as Novec 1230.
  3. When protecting electrical power distribution with an aerosol fire suppression system, we can either protect the whole room or just inside the specific cabinets of risk.
  4. Renewable energy has many risk areas where aerosol fire suppression is an ideal solution. From solar farms to wind turbines, many electrical and mechanical fire hazards require a standalone, compact, cost-effective, and low-maintenance form of fire suppression to safeguard the high-asset value equipment. Also, the BESS (Battery Energy Storage Systems), which are often combined with renewable energy installations, is a good application for aerosol fire suppression, although this should be done in conjunction with the OEM, who often have their recommendations for fire control at BESS installations.
  5. Digital infrastructure such as server and hub rooms or any similar critical infrastructure equipment can be protected with aerosol fire suppression. We’ve already discussed on this page some of the challenges of using aerosol fire suppression within server environments, but the ‘potential’ downsides of having to clean up the dusty residue after an aerosol discharge pale into insignificance when compared to the potential damage that could be caused by a fire!
  6. Fragile and valuables storage, such as at Museums, Art Galleries, Archive Storage, and other similar environments, are suitable applications for aerosol fire suppression.

These areas are rarely suitable for the use of other extinguishing agents, due to the nature of construction in the building, the size of the area, or the risks of water damage when using sprinklers or water mist to protect such valuable and sensitive assets. Aerosol will provide a non-destructive means of cost-effectively protecting these areas.

  • Scientific environments, including laboratories, test cells, and fume cupboards, are typical hazardous applications where aerosol fire suppression is used.
  • Hazardous product storage and high-hazard ATEX areas are commonly protected with aerosol fire suppression. This includes Lithium & Lithium-Ion battery storage, Lithium-Ion charging – BESS, and Fertiliser production.
  • Boiler rooms are critical assets for your facilities and often must be protected with reliable fire suppression. Generally, these areas are tight for space (often tucked into a services basement or similar), which makes aerosol fire suppression ideal for these applications.
  • Manufacturing, automotive, aerospace, and similar engineering applications are ideal for aerosol fire suppression. High-value robotics and machinery plus, plus power distribution systems to the power-hungry equipment make for a lot of different risk areas distributed around your facility. A recent installation by Blazequel saw our team fit aerosol fire suppression into five different robot cells around a manufacturing facility, where the layout of the plant, gaps between the rooms (to allow the process track to move through), and other unique conditions, including a need to keep water away from the machinery, created a risk area which could only be protected by aerosol fire suppression.

I've heard that the 'Aerosol Generators' used on aerosol fire suppression systems emit flames…. Is that true?

If you buy the wrong aerosols – possibly yes! Some of the early generations of aerosol generators were extremely crude, lacking basic safety features in their designs, and did literally emit flames during discharge.

This is because the chemical reaction that takes place during the discharge of an aerosol generator (transforming a solid block of compound into billions of tiny airborne particles) is a high-temperature exothermic reaction. All aerosol generators reach a high temperature during discharge – ask for the datasheets for the product you’re having installed, and the casing temperature and discharge temperature should all be recorded there. 

However, with the new ‘second-generation’ aerosol generator products that we use, there is no concern about them venting flames.

Improvements in technology and the design of the aerosol generator eliminate that possibility. Part of the UL9450 testing that our aerosol generators undergo is that the aerosol is activated and discharged within an explosive atmosphere – and it goes without saying that during discharge, the aerosol is not allowed to ignite that explosive atmosphere!

So, in summary, there is no need to panic. So, as long as you buy quality, certified aerosol systems from reputable suppliers like Blazequel, you don’t need to worry about those outdated aerosol horror stories!

How much does an aerosol fire suppression system cost?

As always… it depends. There are many variables to consider here!

Firstly, let’s assume that you are looking to protect a room and do not require an ATEX-approved aerosol generator.

Secondly, let’s assume that your room is approximately 5m(long) x 4m(wide) x 3m (high).

Thirdly, let’s assume that we can use a cost-effective form of detection. We’ll use a system with a combination of smoke and heat detectors. One smoke detector and one heat detector will have to be activated to discharge the system (or alternatively, the system can be manually released).

For a system like this, you’ll have three main costs to consider:

  1. Detection & Control: For the detection and control system detailed above, you need to allow £5,000-£7,500 + VAT. This cost could double if you need more costly forms of fire detection, such as flame detectors. We can guide you through the options.
  2. Aerosol Generators: The quantity of aerosol generators will depend not only on the volume of the area but also on the type of fire hazard and the leakage rate from the room. Fixing the aerosols on the wall (the larger one can weigh over 25kg) can also affect installation costs. However, for the room detailed above (5mx4mx3m), we have a total protected volume of 60m3. To protect this area with fire suppression, you need to allow £4,000 – £6,000.
  3. Connection to your ‘Building’ fire alarm systems or interfacing with machinery: This is a key consideration that is often overlooked. Generally, you will want to connect your fire suppression system to a building fire alarm for purposes of warning and evacuation. Also, you can shutdown machinery, power supplies, or extract systems in the protected area. However, you should allow anywhere between £500-2,000 for these types of interfacing (which may also require other specialist contractors to interface to their items of equipment for shutdown purposes).

In summary, a system like the one we described above could cost between £9,500 and £23,000 (+VAT) to design, supply, install, and commission. If you’d like to discuss your application, we’ll gladly provide you with an accurate quotation for your aerosol fire suppression requirements.  Call us now!

Are you ready to prioritize safety?

Don’t hesitate to reach out to us, or you can easily fill out the form below. We’re here to assist you.

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