The Nozzle Integrated Helideck System often also called DIFFS (Deck integrated Fire Fighting System) is used to extinguish fires on a Helideck, in both the Helicopter as well as a hydrocarbon pool-fire on the deck.
The system consists of a deluge valve skid with foam, connected to a distribution pipework with a number of pop-up spray nozzles.
The pop-up spray nozzles are installed in the helideck, flush with the surface of the deck.
When the system is activated, the water pressure activates the nozzles, whereby the nozzle baffle will be forced to lift, spraying water in a semi-sphere. The nozzle is further designed to provide an upright jet of water, covering objects on the deck up to 7 meters above deck level.
The nozzles are spaced evenly across the deck to give a design density of 6,5 lpm/m2 of the helideck surface (other densities may be used).
When the system is shut down and reset, the pipework will be drained and the nozzles will drop back into the closed position, effectively closing the nozzle to prevent dirt and debris to enter the pipework.
The helideck system is activated by a deluge skid. For more information on deluge valve operation and foam mixing system See “Deluge valve “, and “Foam Applications”.