In a recent study conducted by the Business Sprinkler Alliance (BSA), 22% of those respondents surveyed felt there was no necessity to include sprinkler installations in industrial and commercial buildings. The reluctance to install automatic fire safety sprinkler systems in commercial and industrial buildings is compounded by misconceptions about safety and efficiency, combined with a lack of helpful and accurate information or clear guidance. Here, in this exclusive article for Risk Xtra (and the start of a new regular BSA feature series for our readers), Iain Cox examines why host organisations may well be missing opportunities that are delivered by automatic sprinklers and their benefits beyond being an effective measure in dealing with the risk of fire.
On Monday 17 June, a fire at the Pirelli tyre factory in Burton upon Trent was suppressed and extinguished by an automatic sprinkler system. This prevented any further damage and allowed the business to be back up-and-running and operational the following day. The fire had broken out in the roof space of the premises on Beech Lane in Stretton with fire crews (numbering upwards of 30 firefighters) from the Staffordshire Fire and Rescue Service attending the blaze. The sprinkler system contained what could have been a potential major fire and ensured that the occurrence was only a minor inconvenience.
The Pirelli fire is an excellent example of a business being prepared for an emergency with sprinklers stopping a fire from spreading. One of at least 200 ‘sprinkler saves’ in large industrial buildings in the last three years, the Pirelli fire demonstrates the effectiveness of sprinkler systems.
Despite the fact that well over 40 million sprinkler heads are fitted annually across the globe, there remains a lack of understanding on their effectiveness and about the fact that they work in a remarkably broad set of situations. According to recent statistics, sprinkler systems have a performance effectiveness of 99% across all building types, while 95% of fires are controlled (or even extinguished) by the operation of fewer than five sprinklers. This debunks the myth that, if one sprinkler goes off, then all of them will*.
Sprinklers are one of those things that are taken for granted or otherwise dismissed. People either understand them and see their true benefits or don’t understand them and all-too-quickly dismiss them without really being able to justify why. From improving life safety through to matters of business protection, continuity and sustainability, the introduction of automatic sprinklers offers many positive benefits. Their inclusion may also permit freedom of design which, in turn, can create savings in the initial capital and lifecycle costs and the construction programme.
Positive impact on building design
We’re all looking for greater flexibility in the work spaces being designed today. Whether it be the usable space, greater sight lines or simply more glazing for natural light, all are under close scrutiny. Each, in turn, offers challenges to the buildings we design from a fire safety perspective. At the same time, our businesses are more connected and interruptions are more costly.
Automatic sprinklers offer an interesting opportunity to meet these challenges while also minimising the impact of fire on an enterprise. An automatic sprinkler system enables the balancing of fire protection measures which then creates a number of significant design opportunities. The automatic sprinklers will operate in a fire to minimise the size and spread of the incident. Therefore, an office which has automatic sprinklers allows occupants more time to escape when fire occurs, which for the designer means they can consider longer travel distances and adjust escape doors and stairs, freeing-up their design. This provides flexibility in the location of staircases and reduces the necessity for introducing escape corridors.
Another design benefit realised by sprinklers is in the number of firefighting shafts and fire mains which can be adjusted. In a building without sprinklers, a firefighting shaft should be provided such that no part of a floor is more than 45 metres from a fire main outlet in a protected stairway. If a building’s fitted with sprinklers, that distance can be increased to 60 metres.
Sprinklers act to limit fire growth such that designers can consider larger compartment sizes. That then offers additional design options. In addition to greater freedom in the building layout, sprinklers can work to contain a fire and limit it to the compartment of origin.
The Building Regulations’ Approved Document B recommends that buildings are separated sufficiently, or that a portion of the building’s external wall should be suitably fire-resistant to prevent fire spreading between buildings. The area of external wall required to be fire-resistant is related to the distance between the external wall and the site boundary. However, because automatic sprinklers inhibit fire size and, therefore, the spread of fire, the non-fire-resistant area of external wall can be doubled, giving designers greater flexibility in external wall design and layout.
A building’s façade, and particularly so for an office, is a sensitive part of the design both in terms of capital cost and aesthetics. It’s one of the more common areas where automatic sprinklers can be used to gain advantage even though standard guidance doesn’t necessarily recommend them.
The link between façade specification and automatic sprinklers arises as there’s a need to ensure the risk of external fire spread between buildings is controlled. This is achieved either by or through a combination of increasing the fire resistance of the external wall of buildings or providing adequate separation.
However, cities are becoming denser and the space within progressively limited and expensive. For this reason, there’s a need to use intuitive design considerations to maximise a building’s footprint. As such, designers desire a glazed façade while building close to the site boundary. In this case, fire-rated glazing is a prerequisite of Approved Document B and BS 9999 in order to prevent fire spread between buildings.
Fire-resistant glazing does come with two drawbacks: cost and weight. That said, as sprinkler systems reduce the thermal radiation emitted from a fire, incorporating such a system into a building yields many benefits. For instance, sprinklers could enable sufficient savings on the cost of the façade to fully offset the cost of the automatic sprinkler system through the difference between the cost of fire-rated and non-fire rated glazing. Although concessions must be made for different distances between buildings and site boundaries, of course, the presence of a sprinkler system reduces the amount of fire-rated glazing that needs to be purchased.
Moving away from façades, there’s a misconception that sprinkler heads cannot be concealed and are visually unappealing. The use of concealed heads, however, ensures that they can be discreet when desired, offering uninterrupted and seamless interiors that, importantly, ensure vital protection from fire.
Dispelling the ‘cost’ myth
A BRE Global study published in 2012 considered all the factors relating to the potential for fire including insurance costs, the upfront sprinkler installation cost and maintenance cost over a 45-year lifetime of a warehouse building larger than 2,000 m2. The study concluded that the whole-life costs will, on average, be 3.5 times lower in those warehouses in which sprinkler systems have been installed.
These figures are driven by lower incidents of fire, and therefore less fire damage, as well as lower insurance premiums over the life of the building. Insurers are so confident of the value of sprinklers that they normally allow fire premium-rate discounts for protected properties.
The consideration of automatic sprinklers at the earliest stages of the design will enable stakeholders to realise and benefit from a wealth of design freedoms. Through robust research and by looking at different building types and design options, the consideration of automatic sprinklers should be part of any robust design development for a new office project.
At the same time, automatic fire sprinkler systems are critical to physical resilience and business continuity. When a fire starts in a building fitted with a fully-functioning sprinkler system, it has a high probability of being contained from the outset and in advance of the Fire and Rescue Services’ arrival. In the great majority of cases, the impacted business is fully-functioning within hours.
In essence, then, fire safety sprinkler systems save lives, reduce the threat posed to firefighters, lessen the burden on the Fire and Rescue Service, save businesses, save jobs and protect the environment.
Iain Cox is Chairman of the Business Sprinkler Alliance
*’Efficiency and Effectiveness of Sprinkler Systems in the United Kingdom: An Analysis from Fire Service Data’, Optimal Electronics (May 2017)