1.2 Definitions
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Resolutions - Maritime Safety Committee - Resolution MSC.370(93) – Amendments to The International Code for The Construction and Equipment of Ships Carrying Liquefied Gases In Bulk (IGC Code) – (Adopted on 22 May 2014) - Annex - Amendments to The International Code for The Construction and Equipment of Ships Carrying Liquefied Gases In Bulk (IGC Code) - Chapter 1 - General - 1.2 Definitions

1.2 Definitions

 Except where expressly provided otherwise, the following definitions apply to the Code. Additional definitions are provided in chapters throughout the Code.

  1.2.1 Accommodation spaces are those spaces used for public spaces, corridors, lavatories, cabins, offices, hospitals, cinemas, games and hobby rooms, barber shops, pantries without cooking appliances and similar spaces.

  1.2.2 "A" class divisions are divisions as defined in regulation II-2/3.2 of the SOLAS Convention.

  1.2.3 Administration means the Government of the State whose flag the ship is entitled to fly. For Administration (port), see port Administration.

  1.2.4 Anniversary date means the day and the month of each year that will correspond to the date of expiry of the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk.

  1.2.5 Boiling point is the temperature at which a product exhibits a vapour pressure equal to the atmospheric pressure.

  1.2.6 Breadth (B) means 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. The breadth (B) shall be measured in metres.

  1.2.7 Cargo area is that part of the ship which contains the cargo containment system and cargo pump and compressor rooms and includes the deck areas over the full length and breadth of the part of the ship over these spaces. Where fitted, the cofferdams, ballast or void spaces at the after end of the aftermost hold space or at the forward end of the foremost hold space are excluded from the cargo area.

  1.2.8 Cargo containment system is the arrangement for containment of cargo including, where fitted, a primary and secondary barrier, associated insulation and any intervening spaces, and adjacent structure, if necessary, for the support of these elements. If the secondary barrier is part of the hull structure, it may be a boundary of the hold space.

  1.2.9 Cargo control room is a space used in the control of cargo handling operations.

  1.2.10 Cargo machinery spaces are the spaces where cargo compressors or pumps, cargo processing units, are located, including those supplying gas fuel to the engine-room.

  1.2.11 Cargo pumps are pumps used for the transfer of liquid cargo including main pumps, booster pumps, spray pumps, etc.

  1.2.12 Cargoes are products listed in chapter 19, that are carried in bulk by ships subject to the Code.

  1.2.13 Cargo service spaces are spaces within the cargo area, used for workshops, lockers and store-rooms that are of more than 2 m2 in area.

  1.2.14 Cargo tank is the liquid-tight shell designed to be the primary container of the cargo and includes all such containment systems whether or not they are associated with the insulation or/and the secondary barriers.

  1.2.15 Closed loop sampling is a cargo sampling system that minimizes the escape of cargo vapour to the atmosphere by returning product to the cargo tank during sampling.

  1.2.16 Cofferdam is the isolating space between two adjacent steel bulkheads or decks. This space may be a void space or a ballast space.

  1.2.17 Control stations are those spaces in which ship's radio, main navigating equipment or the emergency source of power is located or where the fire-recording or fire control equipment is centralized. This does not include special fire control equipment, which can be most practically located in the cargo area.

  1.2.18 Flammable products are those identified by an "F" in column "f" in the table of chapter 19.

  1.2.19 Flammability limits are the conditions defining the state of fuel-oxidant mixture at which application of an adequately strong external ignition source is only just capable of producing flammability in a given test apparatus.

  1.2.20 FSS Code is the Fire Safety Systems Code meaning the International Code for Fire Safety Systems , adopted by the Maritime Safety Committee of the Organization by resolution MSC.98(73), as amended.

  1.2.21 Gas carrier is a cargo ship constructed or adapted and used for the carriage in bulk of any liquefied gas or other products listed in the table of chapter 19.

  1.2.22 Gas combustion unit (GCU) is a means of disposing excess cargo vapour by thermal oxidation.

  1.2.23 Gas consumer is any unit within the ship using cargo vapour as a fuel.

  1.2.24 Hazardous area is an area in which an explosive gas atmosphere is, or may be expected to be present, in quantities that require special precautions for the construction, installation and use of electrical equipment. When a gas atmosphere is present, the following hazards may also be present: toxicity, asphyxiation, corrosivity, reactivity and low temperature. These hazards shall also be taken into account and additional precautions for the ventilation of spaces and protection of the crew will need to be considered. Examples of hazardous areas include, but are not limited to, the followingfootnote:

  • .1 the interiors of cargo containment systems and any pipework of pressure-relief or other venting systems for cargo tanks, pipes and equipment containing the cargo;

  • .2 interbarrier spaces;

  • .3 hold spaces where the cargo containment system requires a secondary barrier;

  • .4 hold spaces where the cargo containment system does not require a secondary barrier;

  • .5 a space separated from a hold space by a single gastight steel boundary where the cargo containment system requires a secondary barrier;

  • .6 cargo machinery spaces;

  • .7 areas on open deck, or semi-enclosed spaces on open deck, within 3 m of possible sources of gas release, such as cargo valve, cargo pipe flange, cargo machinery space ventilation outlet, etc.;

  • .8 areas on open deck, or semi-enclosed spaces on open deck within 1.5 m of cargo machinery space entrances, cargo machinery space ventilation inlets;

  • .9 areas on open deck over the cargo area and 3 m forward and aft of the cargo area on the open deck up to a height of 2.4 m above the weather deck;

  • .10 an area within 2.4 m of the outer surface of a cargo containment system where such surface is exposed to the weather;

  • .11 enclosed or semi-enclosed spaces in which pipes containing cargoes are located, except those where pipes containing cargo products for boil-off gas fuel burning systems are located;

  • .12 an enclosed or semi-enclosed space having a direct opening into any hazardous area;

  • .13 void spaces, cofferdams, trunks, passageways and enclosed or semi-enclosed spaces, adjacent to, or immediately above or below, the cargo containment system;

  • .14 areas on open deck or semi-enclosed spaces on open deck above and in the vicinity of any vent riser outlet, within a vertical cylinder of unlimited height and 6 m radius centred upon the centre of the outlet and within a hemisphere of 6 m radius below the outlet; and

  • .15 areas on open deck within spillage containment surrounding cargo manifold valves and 3 m beyond these up to a height of 2.4 m above deck.

  1.2.25 Non-hazardous area is an area other than a hazardous area.

  1.2.26 Hold space is the space enclosed by the ship's structure in which a cargo containment system is situated.

  1.2.27 IBC Code means the International Code for the Construction and Equipment of Ships carrying Dangerous Chemicals in Bulk , adopted by the Maritime Safety Committee of the Organization by resolution MSC.4(48), as amended.

  1.2.28 Independent means that a piping or venting system, for example, is in no way connected to another system and that there are no provisions available for the potential connection to other systems.

  1.2.29 Insulation space is the space, which may or may not be an interbarrier space, occupied wholly or in part by insulation.

  1.2.30 Interbarrier space is the space between a primary and a secondary barrier, whether or not completely or partially occupied by insulation or other material.

  1.2.31 Length (L) is the length as defined in the International Convention on Load Lines in force.

  1.2.32 Machinery spaces of category A are those spaces, and trunks to those spaces, which contain either:

  • .1 internal combustion machinery used for main propulsion; or

  • .2 internal combustion machinery used for purposes other than main propulsion where such machinery has, in the aggregate, a total power output of not less than 375 kW; or

  • .3 any oil-fired boiler or oil fuel unit or any oil-fired equipment other than boilers, such as inert gas generators, incinerators, etc.

  1.2.33 Machinery spaces are machinery spaces of category A and other spaces containing propelling machinery, boilers, oil fuel units, steam and internal-combustion engines, generators and major electrical machinery, oil filling stations, refrigerating, stabilizing, ventilation and air-conditioning machinery, and similar spaces and the trunks to such spaces.

  1.2.34 MARVS is the maximum allowable relief valve setting of a cargo tank (gauge pressure).

  1.2.35 Nominated surveyor is a surveyor nominated/appointed by an Administration to enforce the provisions of the SOLAS Convention regulations with regard to inspections and surveys and the granting of exemptions therefrom.

  1.2.36 Oil fuel unit is the equipment used for the preparation of oil fuel for delivery to an oil-fired boiler, or equipment used for the preparation for delivery of heated oil to an internal combustion engine, and includes any oil pressure pumps, filters and heaters dealing with oil at a pressure of more than 0.18 MPa gauge.

  1.2.37 Organization is the International Maritime Organization (IMO).

  1.2.38 Permeability of a space means the ratio of the volume within that space which is assumed to be occupied by water to the total volume of that space.

  1.2.39 Port Administration means the appropriate authority of the country for the port where the ship is loading or unloading.

  1.2.40 Primary barrier is the inner element designed to contain the cargo when the cargo containment system includes two boundaries.

  1.2.41 Products is the collective term used to cover the list of gases indicated in chapter 19 of this Code.

  1.2.42 Public spaces are those portions of the accommodation that are used for halls, dining rooms, lounges and similar permanently enclosed spaces.

  1.2.43 Recognized organization is an organization authorized by an Administration in accordance with SOLAS regulation XI-1/1.

  1.2.44 Recognized standards are applicable international or national standards acceptable to the Administration, or standards laid down and maintained by the recognized organization.

  1.2.45 Relative density is the ratio of the mass of a volume of a product to the mass of an equal volume of fresh water.

  1.2.46 Secondary barrier is the liquid-resisting outer element of a cargo containment system, designed to afford temporary containment of any envisaged leakage of liquid cargo through the primary barrier and to prevent the lowering of the temperature of the ship's structure to an unsafe level. Types of secondary barrier are more fully defined in chapter 4.

  1.2.47 Separate systems are those cargo piping and vent systems that are not permanently connected to each other.

  1.2.48 Service spaces are those used for galleys, pantries containing cooking appliances, lockers, mail and specie rooms, store-rooms, workshops other than those forming part of the machinery spaces, and similar spaces and trunks to such spaces.

  1.2.50 Tank cover is the protective structure intended to either protect the cargo containment system against damage where it protrudes through the weather deck or to ensure the continuity and integrity of the deck structure.

  1.2.51 Tank dome is the upward extension of a portion of a cargo tank. In the case of below-deck cargo containment systems, the tank dome protrudes through the weather deck or through a tank cover.

  1.2.52 Thermal oxidation method means a system where the boil-off vapours are utilized as fuel for shipboard use or as a waste heat system subject to the provisions of chapter 16 or a system not using the gas as fuel complying with this Code.

  1.2.53 Toxic products are those defined by a "T" in column "f" in the table of chapter 19.

  1.2.54 Turret compartments are those spaces and trunks that contain equipment and machinery for retrieval and release of the disconnectable turret mooring system, high-pressure hydraulic operating systems, fire protection arrangements and cargo transfer valves.

  1.2.55 Vapour pressure is the equilibrium pressure of the saturated vapour above the liquid, expressed in Pascals (Pa) absolute at a specified temperature.

  1.2.56 Void space is an enclosed space in the cargo area external to a cargo containment system, other than a hold space, ballast space, oil fuel tank, cargo pumps or compressor room, or any space in normal use by personnel.


Copyright 2022 Clasifications Register Group Limited, International Maritime Organization, International Labour Organization or Maritime and Coastguard Agency. All rights reserved. Clasifications Register Group Limited, its affiliates and subsidiaries and their respective officers, employees or agents are, individually and collectively, referred to in this clause as 'Clasifications Register'. Clasifications Register assumes no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant Clasifications Register entity for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract.