Mixing fire with water

Long seen as the domain of the commercial sector, or individual properties with high value contents, sprinkler systems are increasingly being installed in domestic properties or properties of multiple occupancy. The Department of Communities & Local Government has recognised the benefits of fire suppression systems, especially in housing for the most vulnerable.

Planning regulations are now such that many of us will be faced with the option of installing fire sprinklers as an alternative or addition to fire doors when considering the renovation or extension of our homes. In February, legislation was passed by the Welsh Assembly Government that will require all new Welsh properties to have automatic fire sprinkler systems installed at the time of construction.

On the face of it, this is a life-saving initiative which is likely eventually to be followed in England. For water companies, extinguishing fires in their early stages through the activation of sprinklers will have a number of demonstrable benefits – reduced demand on the network by fire tenders at the time of

a more established incident; lower volumes of water used; less need for call outs to control staff or network operators; reduced environmental impacts caused by wash water run-off and a reduction of “unaccounted for water” in water balance figures.

The difficulty arises with the details of providing and maintaining suitable water supplies. The water industry is often criticised as being difficult to work with and unmoving in its requests for separate connections to the mains water network or the installation of meters, storage options or pumps. These requests are either grounded in the legal requirements of the Water Supply (Water Fittings) Regulations 1999 (or equivalents in Scotland and Northern Ireland) or in the logistics of hydraulically providing water at the right pressure and flow to ensure proper sprinkler head function.

Water UK and its member companies have worked with representatives of the sprinkler manufacturers and installers, together with government and regulators, to understand these issues and to address them. In 2004 Water UK, the Fire Sprinklers Association and the British Automatic Sprinklers Association published a guidance document.

This document discussed the water needs of automatic fire sprinkler systems and established guidelines on how these can be met. The conflict that can exist between water providers and sprinkler installers often comes down to thebasic layout of water networks.

In the UK, water networks are designed to provide the high quality drinking water. Drinking water distribution networks are optimised to minimise the travel time of water to prevent the deterioration of the product post treatment and supply pipe connections to houses which give adequate flow rates for domestic purposes. This does not necessarily match the needs of fire fighting. Add to this pressure management and the result is a network that is balanced to provide high quality drinking water, but also to minimise water lost as a result of higher pressure.

This provides a potential conflict for two reasons. Firstly, a poorly designed, installed or maintained system will be a risk to water quality. The reason that the Water Supply (Water Fittings) Regulations were developed was to protect consumers from the detrimental effects of inappropriate fittings attached to the water system on the customer side. Water companies have a duty to enforce these Regulations and will do so where there has been a breach. It is far better to get these addressed at the design and installation stages.

Then there is the issue of metering. All new supplies should be metered, but companies cannot charge for water taken for fire-fighting. This does not mean that fire-fighting water cannot be measured. Metering is purely to monitor against leakage or unauthorised use of water. The challenge for sprinkler systems is that pressure losses caused by meters small enough to measure normal domestic flows can compromise the operation of sprinkler heads. There are technological solutions, but these add cost and complexity to the design.

The statistic that is often quoted is that nobody in the UK has died as a result of a fire in a property that was fitted with a sprinkler system. But what would happen if someone were to die or property was destroyed, because a fire couldn’t be suppressed by a sprinkler system due to a problem with the water supply? Legally, there would generally be no liability on the water provider. Water suppliers are not required to provide water on a 24/7 basis. In this event the impact on traditional fire-fighting would be minimal, as crews would use tenders, pump from surface waters or take from supply zones. In a sprinkler system, there is no alternative. Were someone to die due to a problem with the water supply, the provider would suffer severe harm to their reputation.

This is another reason why it is better to have liaison at the time of design and installation time and also to inform and notify water companies of the location of systems.

The new legislation in Wales highlights the value of automatic fire-sprinklers and the role of the companies who strive to provide enough water at the time of need, whilst ensuring that water quality is not compromised. There are challenges to doing this but – to save lives – we should be able to overcome them.