2 Definitions
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1431 – Guidelines for the Approval of Helicopter Facility Foam Fire-Fighting Appliances – (31 May 2012) - Annex – Guidelines for the Approval of Helicopter Facility Foam Fire-Fighting Appliances - 2 Definitions

2 Definitions

  2.1 D-value means the largest dimension of the helicopter used for assessment of the helideck when its rotors are turning. It establishes the required area of foam application.

  2.2 Deck integrated foam nozzles are foam nozzles recessed into or edge mounted on the helideck.

  2.3 Foam-making branch pipes are air-aspirating nozzles in tube shape for producing and discharging foam, usually in straight stream only.

  2.4 Helicopter landing area is an area on a ship designated for occasional or emergency landing of helicopters, for example as referred to in SOLAS regulation II-2/18.2.2 and not designed for routine helicopter operations.

  2.5 Helideck is a purpose-built helicopter landing platform or other deck area including all structure, fire-fighting appliances and other equipment necessary for the safe operation of helicopters, as referred to in SOLAS regulations II-2/3.26 and 18.5 and the 2009 MODU Code (chapter 1, paragraph 1.3.27).

  2.6 Hose reel foam station is a hose reel fitted with a foam-making branch pipe and non-collapsible hose, together with fixed foam proportioner and fixed foam concentrate tank, mounted on a common frame.

  2.7 Monitor foam station is a foam monitor, either self-inducing, or together with separate fixed foam proportioner, and fixed foam concentrate tank, mounted on a common frame.

  2.8 Obstacle free sector is the take-off and approach sector which totally encompasses the safe landing area and extends over a sector of at least 210º, within which only specified obstacles are permitted.

  2.9 Limited obstacle sector is a 150º sector outside the take-off and approach sector that extends outward from a helideck where objects of limited height are permitted.

  2.10 Winching area is a pick-up area provided for the transfer by helicopter of personnel or stores to or from the ship, while the helicopter hovers above the deck, for example as referred to in SOLAS regulation III/28.


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