Sprinklers explained
One of the biggest advantages of fire sprinklers as a fire fighting tool is their simplicity. Fire sprinklers were invented in the 19th century and although their materials have since been refined, the way they work is unchanged. Fire sprinklers spray water onto a fire while it is still small. The fire then cannot spread and is often extinguished. To make sure this happens, fire sprinklers are fitted in the ceiling at a regular spacing throughout a building and connected to a water piping network that is constantly filled with water under pressure. Each fire sprinkler is held closed by a thermal element. This is usually a small glass bulb filled with a type of alcohol. When there is a fire below the fire sprinkler, the heat makes the alcohol inside the glass bulb expand, just as it does in a thermometer. At a set temperature there is no more room for the alcohol to expand and so it breaks the bulb. The water seal then falls away and the sprinkler starts to spray water onto the fire below. Only the sprinklers above the fire will operate and none of the sprinklers reacts to smoke, such as from cooking. Most fires are controlled by one or two sprinklers. Over more than 100 years fire sprinklers have proven to be very reliable. Europe has never seen a multiple loss of life in a building protected by a functioning fire sprinkler system. Fire sprinklers:
- Almost eliminate fire deaths
- Reduce fire injuries and property losses by over 80%
- Release much less water than fire service hoses so there is less water damage in a fire
- Do not react to smoke or cooking vapours so they only operate when there is a fire
See the fire losses section for more information about the performance of fire sprinklers.
Video of fire tests of first residential sprinkler system in France, installed in June 2017 at a care home in Nerac
Video of French mobile demonstration unit in action
Video produced by Dutch sprinkler association VEBON-NOVB, showing sprinklers in an historic hotel in Amsterdam
Video of fire tests in Bayonne, showing how sprinklers could protect an open staircase
Video produced by Strathclyde Fire & Rescue Service, including a parallel burn demonstration where two old flats in Glasgow are set on fire. One had sprinklers and one did not
Short animation to show how a sprinkler and sprinkler system work
First part of a video from Tayside Fire & Rescue Service, showing how long it can take from the moment a fire starts to the moment the fire service begins to apply water to it. Again, two flats are set on fire, one with sprinklers and one without
Second part of the Tayside Fire & Rescue Service video