Sprinkler head
From Wikipedia, the free encyclopedia
A fire sprinkler is the part of a fire sprinkler system system that discharges water when the effects of a fire have been detected, such as when a predetermined temperature has been reached.
Contents |
[edit] History
In the 1870s, the Parmelee sprinkler head, was introduced in the United States.
[edit] US regulatory requirements
Fire sprinkler application and installation guidelines, and overall fire sprinkler system design guidelines, are provided by the National Fire Protection Association (NFPA) 13.
[edit] Types
| Temperature | Colour | |
|---|---|---|
| °C | °F | |
| 57 | 135 | Orange |
| 68 | 155 | Red |
| 79 | 174 | Yellow |
| 93 | 200 | Green |
| 141 | 286 | Blue |
| 182 | 360 | Mauve |
| 227 260 |
440 500 |
Black |
This chart from the
New Zealand fire
safety standards
indicates the colour
of the bulb and the
respective operating
temperature.
Fire sprinklers can be automatic or open orifice. Automatic fire sprinklers operate at a predetermined temperature, utilizing a fusible link, a portion of which melts, or a frangible glass bulb containing liquid which breaks, allowing the plug in the orifice to be pushed out of the orifice by the water pressure in the fire sprinkler piping, resulting in water flow from the orifice. The water stream impacts a deflector, which produces a specific spray pattern designed in support of the goals of the sprinkler type (i.e., control or suppression). Modern sprinkler heads are designed to direct a spray downward. Each individual automatic fire sprinkler operates individually in a fire. Contrary to as often shown in movies, the entire sprinkler system does not activate, unless the system is a special deluge type.
Open orifice sprinklers are only used in water spray systems or deluge sprinklers systems. They are identical to the automatic sprinkler on which they are based, with the heat sensitive operating element removed.
Automatic fire sprinklers utilizing frangible bulbs follow a standardized colour coding convention indicating their operating temperature. Activation temperatures correspond to the type of hazard against which the sprinkler system protects. Residential occupancies are provided with a special type of fast response sprinkler with the unique goal of life safety.
