In a climate of increasing system choice, the selection of the most appropriate fixed firefighting system can be quite a challenge, as Simon Bird explains.

DESIGN STANDARDS for the very first viable fixed firefighting method, sprinkler systems, have been evolving since the first rules for automatic sprinkler installations were written in the late 1800s. Since then, under the stewardship of various organisations with risk management interests, rules such as BS EN 12845 (BSI, 2009); LPC Rules for Automatic Sprinkler Installations (FPA, 2011); NFPA 13: Installation of Sprinkler Systems (NFPA, 2013); and CEA 4001: Sprinkler Systems Planning and Installation (CEA Property Insurance Committee, 2009) have developed more or less continuously to the present day.

Gaseous fire protection system standards such as BS EN 15004 series (BSI, 2008) have also enjoyed a good number of decades of development and maturation in public forums.

Reliable protection

While some of these technologies may appear rather arcane and even inefficient, another way to look at them is as highly evolved examples of excellent ‘reliability engineering’. In general, they have enviable levels of firefighting performance and reliability, having been developed with the principal aim of supporting business resilience. These performance levels are often used to further the aims of the whole fixed firefighting equipment industry.

Of course, there is a cost associated with the rigour of such evolved technologies and this is perhaps at the root of some worrying selection behaviour we increasingly observe. As Victorian critic and social thinker John Ruskin is reported to have once said: ‘There is hardly anything in the world that some man can’t make a little worse and sell a little cheaper, and the people who consider price only are this man’s lawful prey’.

This is a salutary reminder of where specifiers and the fire engineering community must be careful. Is our motivation to innovate and improve levels of fire safety (performance and reliability) to genuinely achieve good protection, or is it simply to engineer cost out of provisions so that third-party requirements may be satisfied at the lowest price?

Adherence to standards

No right-thinking person would have an issue with efficient use of resources and preventing needless waste, but all too often RISCAuthority sees thinly or even unveiled attempts to cut cost from fire protection provisions that can only be detrimental to performance and reliability. This takes the form of both specifying what is perceived as lower cost alternative technology and omitting essential requirements of tried and tested standards. Standards such as LPC Rules, BS EN 12845 and NFPA 13 have so much knowledge and experience captured within them, that to change any aspect of their provisions is done by the unwitting at great risk.

RISCAuthority therefore advocates the adherence to good quality specifications in any case where it is practical to do so. It has seen many fire engineers, who make what appear to be well-reasoned arguments, deviate from such provisions without realising the significance of what is written and why it was written. Such is the risk and potential consequence that innovation (departure from specification) in this field should only occur when absolutely necessary – for instance, when there is no prescribed solution within, not to reduce cost.

Water mist systems

The situation becomes trickier when other technologies are considered, such as water mist (currently specified by BSI to draft for development (DD) level in the DD 8489 (BSI, 2011) and DD 8458 (BSI, 2010) series, and other newer would-be market entrants.

The pedigree of water mist varies greatly by application. RISCAuthority has no hesitation in recommending its use for certain specific application scenarios, where it is considered to be the unrivalled choice – many food industry local application systems and marine compartment total flooding installations.

Unresolved areas

Furthermore, RISCAuthority does not hold back its loss prevention and risk management experience in identifying the main areas where substantial further development of unresolved issues with the technology exist. In the case of water mist systems, this includes the following problem areas:

• there is no robust hazard evaluation methodology to accompany the DDs (gaseous systems have the ‘design concentration’ approach methodology and BS EN 12845 sprinkler systems have a highly developed methodology)

• there are no applicable component standards dealing with critical fire protection design issues, such as: will the water mist head open?; how reliable is the water mist head?; or how prone to clogging is the water mist head?

• it follows that there are few components approved for fire protection service – which is likely to hinder overall reliability – and these critical components include, to name a few:

  • pumps and pump-sets
  • water mist nozzles (and thermal release elements)
  • valve-sets
  • tanks, pipework, filters and strainers
  • flow switches and alarm devices

• there is no system installation certification scheme – while there is a certification scheme of sorts that audits installing companies, this is not the same as a third-party system installation scheme and it cannot be expected to yield such performance benefits

• as disparate proprietary and competing technologies, the repair strategy cannot incorporate the benefits of standard sizing or interchangeable components – a benefit that is enjoyed by sprinkler systems 

• experience of use of the DDs is currently very limited

• the availability and reliability levels of these systems do not yet benefit from the data collection, analysis and corrective action systems that exist for other more mature approaches to fire protection, such as those with a high level of associated ongoing, third-party surveillance activity

• there are no third-party tested and certified systems to any of the DD parts

• there has been a lack of independent review of the design, performance and reliability of such systems

• perhaps most fundamental of all: these systems are more complex (with higher pressures, smaller orifice sizes and using less water) and therefore likely to be inherently less reliable than other mature standardised technologies cited elsewhere in this article

In the experience of RISCAuthority, it is evident that this lack of maturity and understanding of the such consequence is lost on the overwhelming majority. For example, the Welsh Assembly Government currently seeks to introduce the new Domestic Fire Safety (Wales) Measure 2011 regulation, the purpose of which
is to mandate the installation of fire suppression in all new dwellings in Wales.

In its public consultation on a proposed new regulation, the response form asks: ‘Question 4: Do you agree that the guidance should retain the flexibility to refer to other fire suppression systems when such systems achieve a British Standard?’ (Welsh Government, 2013). RISCAuthority believes that this reflects its attempt to fairly address, from a competition perspective, the issue of different technologies purporting to do broadly the same thing (eg BS 9251 for domestic and residential sprinkler systems and DD 8458 for domestic and residential water mist systems). Quite right too. However, it seems likely that an incorrect assumption has been made that in the field of fixed firefighting systems, different technologies to British Standards will have equivalent levels of firefighting performance. Having extensive involvement in the preparation of British Standards, we know they are not prepared on this basis and it is not safe to assume this to be the case. It would not be possible to achieve this, even if it were the ambition.

RISCAuthority approach

Where does this leave us? RISCAuthority believes we do not have enough comparative system performance data in the UK to undertake any kind of cost benefit study to properly understand the relationship between different technology types, capital costs and aggregated injury and fire loss outcomes. We see no realistic prospect of this data becoming available in the current UK fire safety framework.

Having considered the facts, we are unable to advance beyond the belief that it is unreasonable to expect the immature technologies to offer anywhere near as high a level of protection as the mature equivalents without being specifically engineered to do so – and that involves cost. The use of high specification components with low failure rates, duplication, maintenance regimes and the associated product and installer certification schemes will all push up the cost of these systems, perhaps to a point where they are less competitive against the more mature technologies.

This gives rise to an awkward truth to face up to: doesn’t everyone deserve the best fire protection equipment that it is reasonably practical to specify? And doesn’t the law expect the same?

Simon Bird is associate director of project consultancy at the Fire Protection Association and convenor of RISCAuthority’s Active Working Group

Response to this article is invited that may contribute to an Engineering doctoral study being undertaken by the author at Loughborough University and sponsored by the FPA and RISCAuthority. Please email any comments to


BS EN 15004-1: Fixed firefighting systems. Gas extinguishing systems. Design, installation and maintenance, London, UK, British Standards Institution (BSI), 2008.

BS EN 12845: Fixed firefighting systems – Automatic sprinkler systems – Design, installation and maintenance, London, UK, BSI Group.

DD 8458-1: Fixed fire protection systems. Residential and domestic watermist systems. Code of practice for design and installation, London,

DD 8489-1: Fixed fire protection systems. Industrial and commercial watermist systems. Code of practice for design and installation, London, UK,
BSI, 2011.

CEA 4001: Sprinkler Systems Planning and Installation, Paris, France, CEA Property Insurance Committee, 2009.

LPC Rules for Automatic Sprinkler Installations 2009 Incorporating BS EN 12845, Moreton-in-Marsh, UK, Fire Protection Association, 2011.

NFPA 13: Standard for the Installation of Sprinkler Systems, USA, National Fire Protection Association, 2013.

Consultation Response Form: Domestic Fire Safety (Wales) Measure 2011, Merthyr Tydfil, UK, Welsh Assembly Government, 2013.

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