Welcome to our comprehensive guide on High Pressure Water Mist Systems – your go-to resource for understanding the ins and outs of this crucial fire safety technology.
High-pressure water mist systems are widely used in generator enclosures, industrial plant rooms, machinery spaces and critical infrastructure environments where rapid fire suppression and minimal water usage are required.
SolarFire Systems provides specialist water mist fire suppression system design and installation across the UK and Europe.
In this Frequently Asked Questions (FAQ) post, we'll address common queries surrounding High Pressure Fire Suppression Systems, demystifying their functionality, applications, and maintenance.
Whether you're a facility manager, safety professional, or simply curious about fire safety, read on to gain valuable insights into the world of high pressure water mist fire suppression systems.
What is a high-pressure water mist fire suppression system?
A high-pressure water mist fire suppression system uses specialised nozzles to discharge extremely fine water droplets at high pressure, typically above 80 bar. These droplets rapidly absorb heat, cool the fire environment and displace oxygen at the flame level, helping to control or extinguish fires quickly and efficiently while using far less water than traditional sprinkler systems.
How does a water mist fire suppression system extinguish a fire?
Water mist systems suppress fire through three main mechanisms. The fine water droplets absorb heat and rapidly cool the fire environment, the evaporation of water creates steam which displaces oxygen around the flame, and the mist blocks radiant heat which helps prevent fire spread. These combined effects allow water mist systems to control or extinguish fires effectively.
Where are high-pressure water mist systems commonly used?
High-pressure water mist systems are widely used in environments where effective fire suppression is required but traditional sprinkler systems may cause excessive water damage. Typical applications include generator enclosures, industrial machinery spaces, data centres, turbine enclosures, transport infrastructure and heritage buildings.
Do water mist systems use less water than sprinkler systems?
Yes. Water mist systems typically use significantly less water than conventional sprinkler systems. Because the droplets are extremely fine, they absorb heat more efficiently and suppress fires with a much smaller volume of water. This helps reduce potential water damage to equipment and infrastructure. Water mist systems may also require smaller water storage tanks and can reduce drainage and runoff compared with traditional sprinkler systems.
Are water mist fire suppression systems safe for electrical equipment?
Water mist systems are often suitable for protecting electrical equipment because the small droplet size and reduced water flow minimise the risk of damage compared to conventional sprinkler systems. They are commonly used in generator enclosures, electrical plant rooms and other environments containing electrical infrastructure.
What standards apply to water mist fire suppression systems?
Water mist fire suppression systems are typically designed in accordance with recognised industry standards such as EN 14972 – Fixed Firefighting Systems – Water Mist Systems and NFPA 750 – Standard on Water Mist Fire Protection Systems. System design may also be influenced by manufacturer testing approvals and project-specific fire engineering requirements.
How are high-pressure water mist systems activated?
High-pressure water mist fire suppression systems can be activated in different ways depending on the system design and the type of water mist nozzles installed.
Some systems use open nozzles, where the water mist system is activated by a fire detection system such as smoke or heat detection. Once the detection system confirms a fire condition, the control panel activates the water mist pump system and water is discharged through all open nozzles within the protected zone.
Other systems use closed-head nozzles fitted with frangible glass bulbs, similar to conventional sprinkler heads. In these systems, water is only discharged from the nozzle when the heat from a fire causes the bulb to rupture, allowing water mist to discharge directly at the fire location.
The most appropriate activation method depends on the hazard, enclosure design and fire protection strategy for the protected area.
What is the difference between open nozzle and closed nozzle water mist systems?
Water mist fire suppression systems can be designed using either open nozzles or closed-head nozzles, depending on the fire protection strategy for the protected area.
In an open nozzle system, the nozzles are permanently open and water is released through all nozzles within the protected zone when the system is activated. Activation typically occurs via a fire detection system such as smoke or heat detectors, which signal the control panel to start the water mist pump system and discharge water through the pipework network.
In a closed-head system, each nozzle contains a frangible glass bulb that holds the nozzle closed under normal conditions. When the heat from a fire reaches the rated temperature of the bulb, the glass bulb ruptures and water mist is discharged from that nozzle directly onto the fire area. This type of system operates in a similar way to conventional sprinkler systems.
The most appropriate nozzle type depends on the hazard, enclosure layout and system design requirements for the application.
Open nozzle water mist systems are commonly used in applications such as generator enclosures, turbine enclosures and machinery spaces, while closed-head systems may be used where localised fire suppression similar to conventional sprinklers is preferred.
Can water mist systems replace traditional sprinkler systems?
In some applications, water mist systems can be used as an alternative to traditional sprinkler systems. However, the suitability of water mist depends on the hazard type, enclosure characteristics and applicable fire protection standards. A fire protection specialist should assess the risks and determine the most appropriate system.
What maintenance is required for water mist fire suppression systems?
Like all fire protection systems, water mist systems require regular inspection and maintenance to ensure they remain operational. Maintenance typically includes checking pump systems, pipework, valves, nozzles and control panels, as well as verifying that detection and activation systems are functioning correctly.
What are the advantages of high-pressure water mist fire suppression systems?
High-pressure water mist systems offer several advantages including rapid fire suppression, reduced water consumption, minimal water damage and effective protection for machinery and equipment. These systems are widely used in industrial and infrastructure environments where reliable fire protection is essential.
What pressure do high-pressure water mist fire suppression systems operate at?
High-pressure water mist systems typically operate at pressures above 80 bar, although some systems may operate at significantly higher pressures depending on the manufacturer and system design. The high operating pressure allows the specialised nozzles to produce extremely fine water droplets, which improves heat absorption and fire suppression efficiency.
Are water mist fire suppression systems suitable for generator enclosures?
Yes. Water mist systems are widely used to protect diesel generator enclosures and power generation equipment. Generator installations present significant fire risks due to fuel systems, lubricants and high operating temperatures. Water mist systems provide rapid fire suppression while minimising damage to critical power infrastructure.
Water mist systems are widely used for protecting diesel generators and power generation equipment.
Learn more about generator and acoustic enclosure fire suppression systems
What are the advantages of water mist systems compared to traditional sprinkler systems?
Water mist systems offer several advantages compared with conventional sprinkler systems. They typically use significantly less water, reduce the potential for water damage to equipment and provide rapid cooling of the fire environment. Because the droplets are extremely fine, water mist systems can effectively control or suppress fires in environments where traditional sprinkler systems may not be ideal. Water mist systems may also require smaller water storage tanks and can reduce drainage and runoff compared with traditional sprinkler systems.
Can water mist systems be used instead of gas suppression systems?
In some applications, water mist systems can be used as an alternative to gas suppression systems. The most suitable system depends on the type of hazard, the protected environment and the operational requirements of the facility.
Gas suppression systems are often used in environments such as data centres, control rooms and electrical switch rooms, where protecting sensitive electronic equipment and avoiding water discharge is a priority.
Water mist systems are commonly used in industrial machinery spaces, generator enclosures and turbine areas, where rapid cooling and fire control are required and where a small amount of water discharge is acceptable.
In many projects, the selection between water mist and gas suppression systems is determined through a fire engineering assessment that considers the risk profile, enclosure characteristics and applicable standards.
SolarFire Systems provides both water mist fire suppression systems and gas suppression systems, allowing the most appropriate fire protection solution to be selected for each application.
Need Advice on Water Mist Fire Suppression Systems?
If you are considering installing a water mist fire suppression system or need advice on the most appropriate fire protection solution for your facility, the team at SolarFire Systems can help.
SolarFire Systems provides specialist design, installation and commissioning of engineered fire suppression systems across the UK and Europe, including water mist systems for generator enclosures, industrial plant and critical infrastructure.
If you require further advice on water mist system design, installation or suitability for your facility, SolarFire Systems can provide specialist guidance.
Contact our team today to discuss your project or request further information on 01628 902107 or email us [email protected]
