Fire Sprinkler Systems
Automatic fire sprinkler systems are believed to be the most effective, safest and by far the most reliable ways when it comes to controlling any kind of fire safeguarding both people and property.
How the Sprinkler Systems Work
Generally speaking a typical fire sprinkler system’s sprinklers are installed along the ceiling with standard spacing throughout the protected zone/facility. All sprinklers are connected to a complex water pipe network. This water pipe network is always full of water under pressure in case of emergency.
Each individual fire sprinkler remains closed off by a thermal element. This element typically consists of a smaller glass-like bulb that has been specifically filled with a colour-coded liquid, which is designed to then expand considerably when in contact with heat at a certain temperature. If a fire has broken out beneath the sprinkler, the smallest hint of heat causes the liquid inside the bulb to expand in exactly the same way as it would in a thermometer.
At a certain temperature, there is no other space for the liquid to expand causing the glass bulb to crack and break open. As a result, the water seal drops off and the sprinkler system begins to continuously spray water onto the fire until the area is free-from fire.
The only sprinklers that will operate in such a case are the ones that have been heated to their temperature capacity. 65% of all fires can be controlled by only the operation of one single sprinkler and 95% of all fires can be controlled by 5 or less sprinklers1. These specific types of sprinklers use never react to smoke.
How Fire Sprinkler Systems Work
The least complex and most common reliable kind of automatic fire sprinkler system is known as a Wet Pipe sprinkler system.
This particular fire sprinkler system is made up of a neatly designed network of pipes that supply the spaced sprinklers with water throughout the protected zone. This piping network is always full of pressurised water.
Water is dispensed from a sprinkler when it’s operating onto the fire. The water flow is identified at the sprinklers’ control valves and as a result a signal is sent alerting the fire service of the situation.
The first ever fire alarm sprinkler system was installed in New Zealand during the late 1880s and all approved and recognised sprinkler systems since then have been able to control 99.5% of fires when they have been in operation2
There’s a common misconception that sprinkler systems are accidentally activated on a regular basis, however, this is not true. According to New Zealand’s Insurance Council this is very rare with it only happening with 1 in 16 million sprinklers, which is by far a lot lower than any chance of fire breaking out in any building3
- Fire Protection Association New Zealand Inc., Fire Sprinklers, Retrieved 2008, http://www.fireprotection.org.nz/sprinklers.htm
- 2. NZS4541:2007 - Automatic Fire Sprinkler Systems, Standards New Zealand, Standards Council, 2007.
- 3. New Zealand Fire Service, Building Safety: Engineering FAQ's, Retrieved 2008, http:// www.fire.org.nz/building/faq/engineering_faq.htm