Frequently asked questions about fire sprinklers
How do fire sprinklers work?
Fire Sprinklers are individually triggered by heat from a fire and the sprinkler system will have gained control of the fire long before the Fire & Rescue Service is even notified. Each sprinkler head is connected to a network of pipes and these pipes are connected the a water supply. When the heat from a fire raises the sprinkler to its pre-set operating temperature (usually about 68°C) only the sprinkler head that is affected will operate, delivering water directly to the source of the heat.
Residential Sprinkler Systems are designed specifically for the domestic environment. The sprinkler heads are small, neat and are designed to be unobtrusive, looking very similar to a light fitting.
1. The typical sprinkler head consists of a
plug held in place by a trigger mechanism.
The most common type of trigger is a glass
ampule filled with a glycerin-based liquid that
expands when heated. |
|
2. This liquid is
designed to
expand and break
the tube at a certain
temperature. The
most common are
designed to break at
155 degrees. In the
average sized room,
a 5mm diameter
ampule will usually
break in about one
to one and a half
minutes from
contact with a heat
source. Ampules as
thin as 1mm are
manufactured for a
faster response time.
3. The plug is
forced out by
the pressurized
water behind it and
deflected away by a
beveled edge. The
water sprays over
the deflector plate
which is designed to
distribute it in an
even pattern. Water
will continue to flow
until the main valve
is shut off.
What about water damage?
Typically a sprinkler discharges 50-60 litres per minute. A Fireman's hose on the other hand discharges 200 gallons/minute plus. A sprinkler will use a fraction of the water the Fire & Rescue Service will use to extinguish a fire.
Are fire sprinklers effective?
All fires start small. If detected and tackled early enough a fire can be controlled and extinguished with very little water. Fire Sprinklers operate automatically, even if you are not at home, releasing water directly over the source of the fire and sounding the alarm.
Are fire sprinklers reliable?
Records from Australia and New Zealand (where ALL fires must be reported) between 1886 and 1996 show that sprinklers controlled 99.7% of all fires where they were fitted.
Do fire sprinklers go off accidentally?
Records in service show that sprinklers are very dependable. The chance of a defective head is estimated to be less than 16,000,000:1 |
