14 July 2014

One of the biggest problems facing the owners and operators of premises that house the most vulnerable people in society, is how to protect them from fire. The Fire Industry Association (FIA) and The British Automatic Fire Sprinkler Association (BAFSA) have teamed up to consider how ‘watermist’ could be a major part of the solution.

Fire deaths persist in sheltered accommodation and premises where people are detained; the recent report into the 14 deaths in the fire at the Rose Park care home starkly illustrates this. Low and sometimes non-existent, staffing levels are increasingly being identified in risk assessments that are called for under UK fire safety regulations. Current and projected cut-backs in the Fire & Rescue Services mean those responsible may not be able to rely on the timely arrival of the manpower and resources necessary to save the lives of those at risk. Watermist may be considered as a viable option to ‘protect people at risk’ due to its ease of retrofit in the many existing facilities where timely evacuation in the event of fire is not achievable.

Watermist is ‘Waterspray with droplet diameters less than 1000 microns’. It is the latest fire protection technology providing highly effective fire suppression using very low water flows and is suitable for electrical hazards, ordinary combustibles, flammable liquids and gases.

The key to its effectiveness is the dispersion of water in fine droplets. Water absorbs a large amount of heat by raising its temperature; it absorbs a considerable amount more when converting to vapour, but this can only happen if the droplets are small enough to readily vaporise.

The increased droplet surface area enables them to rapidly cool the environment. Watermist systems use significantly less water than other water based systems, reducing water damage when discharged and reducing the time and effort to restore premises afterwards.

Why is watermist a viable option? Watermist systems can deploy automatic nozzles fitted with ‘quick response’ elements. Each nozzle responds independently to the heat from a fire, hence water is only discharged onto the seat of a fire. Once operated, a mist system offers other significant benefits:

  • It provides effective fire suppression while efficiently using small quantities of water
  • It makes the environment survivable for longer through rapid cooling of the fire and its surroundings
  • It reduces the soot particles in smoke

Watermist is safe for people and safe for the environment, has low water consumption and minimal contamination, with no unpleasant or toxic residues.

Watermist nozzles and systems use significantly less water than other water based suppression systems, reducing water damage when discharged onto a fire and reducing the time and effort to restore premises afterwards.

The key issue for the protection of existing premises is the practicality of installing watermist, or any other fire protection system, including the feasibility of doing so without disruption or displacement of residents. Watermist systems use small bore pipework, which is lighter, quicker and easier to fit in existing premises.

The other ‘problem’ with retrofitting active fire protection systems is finding the space for water storage, pumps and control equipment. But watermist comes up trumps as the reduced water demand means less water storage space and pumping capacity power required.

The benefits of watermist protection can only be realised where the systems are engineered in compliance with recognised standards. British Standards DD 8458 (Domestic & Residential Watermist Systems) and DD 8489 (Commercial & Industrial Watermist Systems) are the most relevant to UK needs. However, it is also essential to employ watermist specialists who can provide independent third party evidence of fire tests which validate the performance of their system design. All mist system designs are based upon live fire tests by independent third parties, which establish and verify the performance of the mist nozzles at the specified spacing. The independent third party reports of these tests will be available from all competent mist specialists.

Finding a competent specialist is easy as they will be members of the major trade associations – BAFSA and the FIA. Both require that member companies have ISO 9000 quality assurance schemes in place – ensuring third party auditing of their design and installation procedures.

One of the most effective means of ensuring the safety of residents and staff is to fit, or retrofit, a watermist system.

Bob Whiteley

Chairman of the Joint BAFSA & FIA Watermist Working Group