Sprinkler systems to BS EN 12845 are designed to extinguish or at least control fires in the early stages of development. In essence a sprinkler system is a network of pipes fed by a water supply via a set of control valves. Sprinkler heads are fitted at specific locations throughout the building and these temperature operated devices discharge water onto fires in specially designed spray patterns. The systems are fitted with alarms, visual and audible, which will be triggered when there is a flow of water in the pipework.

For sprinklers to operate successfully the systems need to be designed, installed and maintained to a high standard. The systems may not be required to operate for many years, but always need to be ready to do so.