Regulations

  Regulation 1(3) General

• R.1(3)-1 In applying these novel craft provisions, the resulting gross and net tonnages should be reflective of the ship's overall size and useful capacity, respectively. A novel type of craft should be understood as one which is novel in its design and should not include existing traditional types of ships of usual shape or those types already covered by the Unified interpretations.

  Regulation 2 Definition of terms used in the annexes

  Regulation 2(1) Upper deck

• R.2(1)-1 A discontinuity in the upper deck which extends over the full breadth of the ship and is in excess of 1 m in length should be treated as a step as defined in regulation 2(1).

• R.2(1)-2 Steps situated outside the "length" (article 2(8)) should not be considered.

• R.2(1)-3 A discontinuity in the upper deck which does not extend to the side of the ship should be treated as a recess under the upper deck level.

• R.2(1)-4 In a ship having openings in the side of the ship below the uppermost deck, which are not closed but limited inboard by weathertight bulkheads and decks, the deck below such openings should be considered the upper deck.

• R.2(1)-5 The Administration may decide on the term "watertight" as a special definition for tonnage purposes is not needed.

  Regulation 2(3) Breadth

• R.2(3)-1 The term "amidships" should be considered as the midpoint of the length as defined in article 2(8) where the forward terminal of that length coincides with the fore side of the stem.

  Regulation 2(4) Enclosed spaces

• R.2(4)-1 In regulation 2(4) there is no contradiction between the definition of enclosed spaces as being "bounded by the ship's hull, by fixed or portable partitions ... " and "… nor the absence of a partition or bulkhead, shall preclude a space from being included in the enclosed space".

• R.2(4)-2 Space located within the boundaries of "permanent or movable awnings" should be subject to treatment under regulation 2(5).

• R.2(4)-3 Tanks, permanently located on the upper deck, provided with removable pipe connections to the cargo system or the vent (de-airing) lines of the ship, should be included in V_c.

• R.2(4)-4 The volume of weathertight steel pontoon covers on hatchway coamings should be included in the calculations of the total volume (V) of the ship. If such covers are open on the underside, their volume should also be included in V_c.

• R.2(4)-5 Multipurpose ships which have the facility to trade with cargo hatches open or closed should always be measured with the hatch covers considered to be closed.

• R.2(4)-6 Masts, kingposts, cranes, crane and container support structures, which are completely inaccessible and above the upper deck, separated on all their sides from other enclosed spaces should not be included in the total volume of all enclosed spaces. Air trunks having a cross-sectional area not exceeding 1 m² may also be excluded under the before-mentioned conditions.

• R.2(4)-7 If enclosed spaces comply with the conditions for exclusion specified in regulation 2(5), then they should be excluded from the total volume of all enclosed spaces (V). Such spaces should be treated as "enclosed but excluded spaces" to differentiate from "enclosed and included spaces" (those "enclosed spaces" which do not comply with the conditions for exclusion specified in regulation 2(5)).

• R.2(4)-8 Open gratings that are part of the ship's hull, or of any deck, covering, partition or bulkhead, are not considered to bound enclosed space, and are ignored when applying this regulation.

• R.2(4)-9 Machinery such as mooring and towing equipment, winches, revolving cranes, cranes with truss structures, and other similar items should not be included in the total volume of all enclosed spaces (V).

• R.2(4)-10 Mobile cranes should not be included in the total volume of all enclosed spaces (V). "Mobile" means that the main structure (support) of the crane moves either longitudinally or transversely relative to the ship.

  Regulation 2(5) Excluded spaces

• R.2(5)-1 The space between the side longitudinal bulkhead of a deckhouse and the bulwark below a deck extending from side to side supported by stanchions or vertical plates connected to the bulwarks, should be treated as an excluded space in accordance with regulation 2(5)(b) and (c). Similarly, open spaces directly below a bridge wing structure should not be treated as enclosed spaces.

• R.2(5)-2 In the case of a ro-ro ship, for example, where the space at the end of an erection is fitted with means for securing cargo, the space should be included in V in accordance with the first condition of regulation 2(5).

• R.2(5)-3 In applying this regulation:

  • .1 spaces excluded from the total volume of all enclosed spaces (V) are those spaces which are treated as enclosed ones under regulation 2(4) but also comply with the conditions for exclusion under regulation 2(5);

  • .2 the volume of those enclosed spaces referred to in regulation 2(5)(a) to (e) shall be excluded from the total volume of all enclosed spaces (V), unless at least one of the following three conditions takes place:

    • - the space is fitted with any means for securing cargo or stores;

    • - the openings are fitted with any means of closure;

    • - the construction provides any possibility of such openings being closed.

• R.2(5)-4 In Appendix 1 to the Convention, labeling in the figures should be interpreted as follows:

  • .1 "O = excluded space" refers to an enclosed space or part of an enclosed space which corresponds to one of the situations described in regulation 2(5)(a) to (e) and which satisfies the conditions for exclusion from the total volume of all enclosed spaces (V) specified in this regulation;

  • .2 "C = enclosed space" refers to an enclosed space or part of an enclosed space which does not correspond to any of the situations described in regulation 2(5)(a) to (e) and consequently can never be excluded from the total volume of all enclosed spaces (V);

  • .3 "I = space to be considered as an enclosed space" refers to an enclosed space or part of an enclosed space which corresponds to one of the situations described in regulation 2(5)(a) to (e) but does not satisfy the conditions for exclusion from the total volume of all enclosed spaces (V) specified in this regulation.

• R.2(5)-5 In applying regulation 2(5)(b) and (c), stanchions necessary to support an overhead deck and vertical railings are not considered to close or reduce the size of a side opening. Horizontal bars connecting vertical railings should not be treated as rails as described in regulation 2(5)(b).

• R.2(5)-6 When applying the provisions of regulation 2(5), the phrase "breadth of the deck" means the breadth of the deckhouse structure at the line of the opening of the space, regardless of whether or not the structure extends from side to side. In addition to erections extending from side to side, the requirements for excluded spaces under regulation 2(5) are also applicable to structures that do not extend from side to side of the ship. In such structures B means breadth of a structure that does not extend from side to side, measured in way of the opening (see appendix 1 to the Convention).

• R.2(5)-7 Grates covering side or end openings should not be considered as means of closure when applying this regulation.

  Regulation 2(5)(d) Space immediately below an uncovered opening

• R.2(5)(d)-1 The term "immediately below" means extending from the deck in which the opening occurs to the lower boundary of the opening being considered. Openings which penetrate the upper deck (as defined in regulation 2(1)) are only excluded to the line of the upper deck.

  Regulation 2(6) Passenger

• R.2(6)-1 N₁ and N₂ should be obtained from the Administration's maritime safety authority.

  Regulation 2(7) Cargo spaces

• R.2(7)-1 The volumes of the segregated ballast tanks should not be included in V_c provided they are not to be used for cargo.

• R.2(7)-2 The volumes of clean ballast tanks in oil tankers should be included in V_c when the ship is fitted with a crude oil washing system which would permit dual purpose cargo/clean ballast tank use of these tanks.

• R.2(7)-3 The volumes of dedicated clean ballast tanks should not be included in V_c provided that:

  • .1 the tanks are not used for cargo;

  • .2 the ship carries a single IOPP Certificate which indicates it is operating with dedicated clean ballast tanks in accordance with regulation 13A, Annex I, MARPOL 73/78;

  • .3 the following notation is inserted in the REMARKS column on the International Tonnage Certificate (1969): "This ship carries an IOPP Certificate in conformity with regulation 13A, Annex I, MARPOL. The following tanks are dedicated solely to the carriage of clean ballast water: ________."

• R.2(7)-4 The volumes of slop tanks for cargo residues should be included in V_c.

• R.2(7)-5 In fishing vessels, the volumes of fish processing spaces for fishmeal, liver oil and canning, tanks for re-cooling fish, wet fish bunkers, stores for salt, spices, oil and tare should be included in V_c. Fishing gear stores should not be included in V_c.

• R.2(7)-6 The volume of refrigerating machinery used for refrigerating cargoes and situated within the boundaries of the cargo spaces should be included in V_c.

• R.2(7)-7 The volumes of mail rooms, baggage compartments separate from passenger accommodation, and bonded stores for passengers should be included in V_c. The volume of provision rooms for crew or passengers and bonded stores for crew should not be included in V_c.

• R.2(7)-8 On combination carriers, where the owners request to have the dual purpose oil/ballast tanks converted to ballast tanks and excluded from V_c, the ballast tanks should be required to be permanently disconnected from the oil cargo system and not used for the carriage of cargo. The ship should then be remeasured in accordance with regulation 5(3). Any ballast tanks not to be included in V_c should be solely allocated to ballast, connected to an independent ballast system, and not used to carry cargo.

• R.2(7)-9 When determining the volumes of cargo spaces, no account should be taken of insulation, sparring or ceiling which is fitted within the boundaries of the space concerned. For ships which have permanent independent cargo tanks constructed within the ship, e.g. gas tankers, the volume to be included in V_c should be calculated to the structural boundary of such tanks, irrespective of insulation which may be fitted on the inside or outside of the tank boundary.

• R.2(7)-10 The volumes of dual purpose spaces such as those used for both ballast and cargo should be included in V_c.

• R.2(7)-11 Spaces allocated to passenger automobiles should be included in V_c.

  Regulation 3 Gross tonnage

• R.3-1 The K₁ coefficient used in the gross tonnage calculation may be derived from either the table in appendix 2 of the Convention or from the formula in regulation 3 at the discretion of the Administration.

• R.3-2 The final tonnage figure determined in accordance with regulation 3 and stated in the tonnage certificate should be given in rounded down figures without decimals.

  Regulation 4 Net tonnage

• R.4-1 The K₂ coefficient used in the net tonnage calculation may be derived from either the table in appendix 2 of the Convention or from the formula in regulation 4 at the discretion of the Administration.

• R.4-2 The final tonnage figure determined in accordance with regulation 4 and stated in the tonnage certificate should be given in rounded down figures without decimals.

  Regulation 6 Calculation of volumes

• R.6-1 Enclosed spaces above the upper deck, appendages and spaces open to the sea not exceeding 1 m³ should not be measured.

  Regulation 6(2) Appendages

• R.6(2)-1 Bulbs, fairwaters, propeller shaft bossings or other structures should be treated as appendages.

  Regulation 6(3) Spaces open to the sea

• R.6(3)-1 Hawse pipes, sea-valve recesses, thruster tunnels, stern chutes in fishing vessels, dredging wells in dredgers and other similar spaces fitted in the ship's hull should be dealt with as spaces open to the sea.

• R.6(3)-2 Volumes within the hulls of ships, such as split-hull barges and dredgers, should be retained in V and V_c notwithstanding that the space within the hull is temporarily opened to the sea when discharging cargo.

• R.6(3)-3 Spaces open to the sea should not be excluded from the total volume of all enclosed spaces (V) if they are used for cargo and/or buoyancy purposes.

  Regulation 7 Measurement and calculation

• R.7-1 When a tonnage certificate and a copy of the calculations of the tonnages are transmitted to another Government in accordance with article 8(2) or 10(3) of the Convention, they should be accompanied by a form as shown in the annex, showing the main particulars of the tonnage calculations for easy reference. When listing underdeck volumes, the volumes may be combined (e.g. underdeck/extended forecastle, etc.) on the form.

  Regulation 7(2) Calculation methods and accuracy

• R.7(2)-1 Administrations should decide on the degree of accuracy required for the tonnage calculations.