Fire sprinkler
systems
Fire sprinkler systems are often part of a complete fire
protection plan, where they are built into the fire alarm
system. They are designed to either kill off a fire or contain
it until more help arrives. Although mostly for large buildings
with large fire safety systems, there are also smaller fire
sprinkler systems available today, for small households.
It has been proven many times, that fire sprinklers are able
to prevent or lessen the risk of death from fire breakouts, by
as much as 80%. It is a good idea to install a fire sprinkler
system if you can afford one.
In some countries with strict building safety codes, fire
sprinklers are required to be installed in all high rise
buildings where firefighters often have difficulty getting
access to, and bringing water to that height. Obviously, fire
sprinklers can put out a fire, even before the fireman
arrives.
Types of fire sprinkler systems
There are several types of fire sprinkler systems, but they
are usually
- Wet pipe systems
- Dry pipe systems
- Deluge systems
The wet pipe systems are connected to a main water supply,
and always have water in the piping, while the dry pipe systems
do not. Dry pipe systems have their piping filled with air
while the water resides in a separate area, and a safety valve
keeps them in place.
When the valve is released due to a fire, the water will
then gush into the piping system, and out the sprinkler heads.
They are normally installed in places subjected to freezing
temperatures, and have a slower response time compared to wet
pipe systems.
Deluge systems will have all their heads spraying water at
the same time. They are the most effective in putting out fires
on the spot. Other types of fire sprinklers include foam water
sprinklers, which spray water and anti fire foam concentrate on
the fire.
How do fire sprinklers work?
A fire sprinkler system is just a water piping
system with sprinkler heads installed at intervals. The
sprinkler heads are fitted on the ceiling. Each fire
sprinkler head operates independently of the others, and
has a heat sensitive bulb filled with liquid that explodes
when the bulb is exposed to a certain temperature. Less
commonly, some designs have heat sensitive metal
instead.
The bulb is connected to a seal which stops the water from
coming out. However, if there is a fire nearby, the high
temperature will cause the pressure of the liquid in the bulb
to rise, and when it gets too much, the bulb will shatter,
releasing the water from the piping that is connected to it.
This temperature threshold varies from one sprinkler design to
another. Some only break at very high temperatures. These will
have a different color code.
The water gushes out from valves at the
sprinkler head and hits the deflector which breaks it up
into droplets which fall over a wide area. In Early
Suppression Fast Response (ESFR) sprinklers, the water
pressure is more than double that of conventional
sprinklers.
The action of one fire sprinkler head is usually sufficient
to put out a fire, but if it is not, the heat from the fire
will trigger other nearby fire sprinklers to help out. The
entire process is automatic, yet highly effective.
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