How Sprinklers Work?
Sprinkler heads are activated by heat from a fire.
They will not operate until the temperature reaches 57°C, 68°C or 74°C depending on the style of sprinkler installed. In the event of a fire, smoke and toxic gases rise and spread quickly along the ceiling and heat the air into the room.
In a room without sprinklers this hot air forces a curtain of deadly gases down the walls, making escape more difficult. The hot air will continue to heat until such point that the entire contents of the room will become so hot the contents will ignite spontaneously. This is known as a flashover and usually occurs at 500°C. Even a small smoldering fire acts like a heat engine as it steadily increases the air temperature above it.
Protect24 sprinkler systems provide protection against this. As the hot air from a fire rises and fans out across the ceiling it heats up the nearest sprinkler head. As soon as the trigger mechanism is heated to 57°C the cover plate falls triggering the sprinkler head and immediately begins to discharge water. The immediate cooling of the heat source will usually control the fire and in most cases extinguish it. Often one, or two sprinkler heads are enough to control a fire. The activation of a sprinkler head triggers a fire alarm to the property affected by fire, and immediately alerts the fire brigade.
Those residents physically able to can now evacuate the building. Those residents requiring assistance now have crucial additional time as the sprinklers control the fire.
Sprinkler heads are spaced in accordance with each manufacturer recommendation, but as a guide they are found at 4.9m x 4.9m spacings. A room of 8m long x 4m wide would have two sprinkler heads in the centre of the width of the room and 4m apart.
Sprinkler heads are concealed behind a decorative cover plate. This means the sprinkler heads are not intrusive or subject to vandalism. The decorative plate is made of metal and held in place with soluble links which melt away when the temperature reaches 57°C. As the decorative plate falls away the sprinkler head will begin discharging water to contain, and ultimately stop the fire.
Residential sprinkler systems are designed to discharge water for up to 30 minutes, unless firefighters or trained operatives disengage the system.
Protect24 install both ceiling and wall mounted sprinklers. Wall mounted sidewall sprinklers are preferred for retrofit works as the sprinkler heads discharge water across a room, and therefore mitigate the requirement for additional pipework.
Furniture soaked with water discharged from the sprinkler system can be cleaned, dried out and reused.
Sprinkler Key Numbers
- 99% of fires are controlled by sprinklers
- Sprinklers reduce injuries by at least 80%
- Property damage is reduced by 90% when sprinklers are fitted
- No-one has ever died in the UK in a fire within a building fitted with sprinklers
- 16 million to one chance of accidental sprinkler discharge
- Sprinkler heads discharge at 68°C
- 60% chance of surviving domestic fire where smoke detectors are fitted
- 95% chance of survival where sprinklers are fitted
- Fire sprinklers reduce fire damage by up to 97%
- 90% reduction in water usage to fight a fight at home
Facts not Fiction
There are many misconceptions about sprinkler systems – bought about mostly by the way they are portrayed on television and film. Images of sprinklers going off on mass and gallons of water flowing through buildings could not be further from the truth.
Let’s establish the fact from the fiction:
Sprinklers may go off accidentally
There is more chance of winning the lottery than sprinklers discharging accidentally. According to the National Fire Sprinkler Network the odds are 1 in 16 million.
Sprinkler heads leak
This is not true. Sprinkler systems are under the same pressure as regular plumbing systems but are tested at two-three times higher pressure during installation.
Sprinkler heads all activate at once
Not true. Sprinkler heads react to temperatures in each room individually. Normally only the sprinkler over the fire will activate, and generally this will control the fire.
Sprinklers cause water damage
Test show that sprinklers cause less damage than the water discharged from a fire fighters hose – and reduce fire damage by up to 80%
Smoke detectors provide enough protection
Smoke detectors save lives by providing an early warning to a smoke or fire incident, but can do nothing to extinguish a growing fire or protect those physically unable to escape on their own, such as the elderly or small children.
Sprinklers: The Benefits
More than 70 million sprinkler heads are installed worldwide each year.
Firefighters believe they provide the ultimate protection for occupants of buildings.
They virtually eliminate the risk of death – no-one in the UK has ever died as a result of a fire in a building fitted with sprinklers – and reduce injuries by at least 80%.
Property damage is reduced by 90% because of the targeted release of water from sprinkler heads whilst damage to the environment is substantially reduced.
Sprinklers are dependable. Whilst fire alarms and smoke detectors warn of a fire starting they still require a person, or automated system to call the fire brigade.
Sprinkler systems provide both a warning of fire – by triggering alarms and warning the fire brigade – but act swiftly to control it.
In most cases, the fire has been controlled by the sprinkler system before the fire brigade have even been alerted.
More than 60% of fire casualties are physically or mentally disadvantaged, and therefore their escape from fire is either prevented completely or at least hindered.
The presence of sprinkler system will control the fire – ensuring those occupants who are unable to escape or require help have an increased time for evacuation.
Sprinkler heads use substantially less water than Fire Brigade hoses, between 1/25th and 1/100th of the water used by a standard fire hose.
According to the National Fire Sprinkler Network more than 300 people in the UK die every year as a result of fires – and 75% of fire casualties occur at home – and the number would be dramatically reduced with the implementation of fire sprinkler systems.