Types of Fire Sprinkler Systems
There are various types of fire sprinkler system installations which are defined as follows:
WET - A wet pipe system is permanently charged with water, thus water is instantaneously discharged from a sprinkler when it actuates. This system is suitable for premises with adequate heating or normal conditions.
DRY - A dry pipe system is suitable for premises where low temperatures
could cause a wet pipe system to freeze e.g. Cold Stores. Dry pipe systems
are charged with compressed air. When the sprinkler head actuates, the air
is released so that water can flow through the pipe work and reach the fire.
ALTERNATE - An alternate pipe system is charged with compressed air
during the Winter and water for the remainder.
TAIL END - A tail end pipe system is where a small section of a Wet
System is kept 'dry' during the Winter e.g. A canopy.
PRE-ACTION - An electrical fire detection system is fitted in conjunction
with a dry pipe system, which is water filled in advance of sprinkler operation
e.g. A computer suite.
