1.3 Definitions
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1.3 Definitions

 For the purpose of this Code the definitions given hereunder apply. For terms used, but not defined in this Code, the definitions as given in the 1974 SOLAS Convention apply.

  1.3.1 Administration means the Government of the State whose flag the ship is entitled to fly.

  1.3.2 A passenger ship is a ship which carries more than twelve passengers as defined in regulation I/2 of the 1974 SOLAS Convention, as amended.

  1.3.3 A cargo ship is any ship which is not a passenger ship.

  1.3.4 A fishing vessel is a vessel used for catching fish, whales, seals, walrus or other living resources of the sea.

  1.3.5 A special purpose ship means a mechanically self-propelled ship which, by reason of its function, carries on board more than 12 special personnel as defined in paragraph 1.3.3 of the IMO Code of Safety for Special Purpose Ships (resolution A.534(13)), including passengers (ships engaged in research, expeditions and survey; ships for training of marine personnel; whale and fish factory ships not engaged in catching ships processing other living resources of the sea, not engaged in catching; or other ships with design features and modes of operation similar to ships mentioned above which, in the opinion of the Administration may be referred to this group).

  1.3.6 An offshore supply vessel means a vessel which is engaged primarily in the transport of stores, materials and equipment to offshore installations and designed with accommodation and bridge erections in the forward part of the vessel and an exposed cargo deck in the after part for the handling of cargo at sea.

  1.3.7 A mobile offshore drilling unit (MODU) or unit is a ship capable of engaging in drilling operations for the exploration or exploitation of resources beneath the sea-bed such as liquid or gaseous hydrocarbons, sulphur or salt:

  • .1 a column-stabilized unit is a unit with the main deck connected to the underwater hull or footings by columns or caissons;

  • .2 a surface unit is a unit with a ship- or barge-type displacement hull of single or multiple hull construction intended for operation in the floating condition;

  • .3 a self-elevating unit is a unit with moveable legs capable of raising its hull above the surface of the sea.

  1.3.8 A dynamically supported craft (DSC) is a craft which is operable on or above water and which has characteristics so different from those of conventional displacement ships, to which the existing international conventions, particularly SOLAS and Load Line, apply, that alternative measures should be used in order to achieve an equivalent level of safety. Within the aforementioned generality, a craft which complies with either of the following characteristics would be considered a DSC:

  • .1 if the weight, or a significant part thereof, is balanced in one mode of operation by other than hydrostatic forces;

  • .2 if the craft is able to operate at speeds such that the Froude number is equal to or greater than 0.9.

  1.3.9 A high-speed craft (HSC) is a craft capable of a maximum speed, in metres per second (m/s), equal to or exceeding:

where:
∇ = displacement corresponding to the design waterline (m3).

  1.3.10 An air-cushion vehicle is a craft such that the whole or a significant part of its weight can be supported, whether at rest or in motion, by a continuously generated cushion of air dependent for its effectiveness on the proximity of the surface over which the craft operates.

 When the revision of the Intact Stability Code is undertaken, the standards for dynamically supported craft will be replaced by the provisions of the High Speed Craft (HSC) Code currently under development.

  1.3.11 A hydrofoil boat is a craft which is supported above the water surface in normal operating conditions by hydrodynamic forces generated on foils.

  1.3.12 A side wall craft is an air-cushion vehicle whose walls extending along the sides are permanently immersed hard structures.

  1.3.13 A containership means a ship which is used primarily for the transport of marine containers.

  1.3.14 Freeboard is the distance between the assigned loadline and freeboard deck.footnote

  1.3.15 Length of ship. The length should be taken as 96% of the total length on a waterline at 85% of the least moulded depth measured from the top of the keel, or as the length from the fore side of the stem to the axis of the rudder stock on the waterline, if that be greater. In ships designed with a rake of keel the waterline on which this length is measured should be parallel to the designed waterline.

  1.3.16 A moulded breadth is the maximum breadth of the ship measured amidships to the moulded line of the frame in a ship with a metal shell and to the outer surface of the hull in a ship with a shell of any other material.

  1.3.17 A moulded depth is the vertical distance measured from the top of the keel to the top of the freeboard deck beam at side. In wood and composite ships, the distance is measured from the lower edge of the keel rabbet. Where the form at the lower part of the midship section is of a hollow character, or where thick garboards are fitted, the distance is measured from the point where the line of the flat of the bottom continued inwards cuts the side of the keel.

In ships having rounded gunwales, the moulded depth should be measured to the point of intersection of the moulded lines of the deck and side shell plating, the lines extending as though the gunwale were of angular design.

Where the freeboard deck is stepped and the raised part of the deck extends over the point at which the moulded depth is to be determined, the moulded depth should be measured to a line of reference extending from the lower part of the deck along a line parallel with the raised part.

Parent topic: Chapter 1 - General
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