INTERNATIONAL CODE FOR THE CONSTRUCTION AND EQUIPMENT OF SHIPS CARRYING LIQUEFIED GASES IN BULK (IGC CODE)

 

Resolution MSC.5(48) 06.17.1983
for ships constructed on or after 07.01.1986

 

With the amended

 

 

 

Foreword

 

At its forty-eighth session (June 1983), the Maritime Safety Committee (MSC) of the International Maritime Organization (IMO) adopted far-reaching amendments to the International Convention for the Safety of Life at Sea (SOLAS), 1974, by resolution MSC.6(48).

 

The amendments consisted of complete replacement texts of chapters III and VII and changes in chapters II-1, ll-2 and lV.

 

The new chapter VII made the provisions of the International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code), which had been adopted by resolution MSC.5(48), mandatory under the 1974 SOLAS Convention.

 

This edition of the IGC Code incorporates amendments adopted by the MSC by resolution MSC.30(61), MSC.32(63), MSC.59(67) and amendments proposed for adoption by the MSC by resolution MSC.22(69).

 

 

Preamble

 

1          The purpose of this Code is to provide an international standard for the safe carriage by sea in bulk of liquefied gases and certain other substances listed in chapter 19 of the Code, by prescribing the design and construction standards of ships involved in such carriage and the equipment they should carry so as to minimize the risk to the ship, to its crew and to the environment, having regard to the nature of the products involved.

 

2          The basic philosophy is one of ship types related to the hazards of the products covered by the Code. Each of the products may have one or more hazard properties which include flammability, toxicity, corrosivity and reactivity. A further possible hazard may arise due to the products being transported under cryogenic or pressure conditions.

 

3          Severe collisions or strandings could lead to cargo tank damage and result in uncontrolled release of the product. Such release could result in evaporation and dispersion of the product and, in some cases, could cause brittle fracture of the ship's hull. The requirements in the Code are intended to minimize this risk as far as is practicable, based upon present knowledge and technology.

 

4          Throughout the development of the Code it was recognized that it must be based upon sound naval architectural and engineering principles and the best understanding available as to the hazards of the various products covered; furthermore that gas carrier design technology is not only a complex technology but is rapidly evolving and that the Code should not remain static. Therefore the Organization will periodically review the Code taking into account-both experience and future development.

 

5          Requirements for new products and their conditions of carriage will be circulated as recommendations, on an interim basis, when adopted by the Maritime Safety Committee of the Organization, prior to the entry into force of the appropriate amendments, under the terms of article VIII of the International Convention for the Safety of Life at Sea, 1974.

 

6          The Code primarily deals with ship design and equipment. In order to ensure the safe transport of the products the total system must, however, be appraised. Other important facets of the safe transport of the products, such as training, operation, traffic control and handling in port, are being or will be examined further by the Organization.

 

7          The development of the Code has been greatly assisted by the work of the International Association of Classification Societies (IACS) and full account has been taken of the IACS Unified Requirements for Liquefied Gas Tankers in chapters 4, 5 and 6.

 

8          The relevant work of the International Electrotechnical Commission (IEC) has contributed substantially to the development of chapter 10.

 

9          Chapter 18 of the Code dealing with operation of liquefied gas carriers highlights the regulations in other chapters that are operational in nature and mentions those other important safety features that are peculiar to gas carrier operation.

 

10        The layout of the Code is in line with the International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (IBC Code) adopted by the Maritime Safety Committee at its forty- eighth session.

 

Chapter 1
GENERAL

1.1       Application

 

1.1.1    The Code applies to ships regardless of their size, including those of less than 500 tons gross tonnage, engaged in the carriage of liquefied gases having a vapour pressure exceeding 2.8 bar absolute at a temperature of 37.8°C, and other products as shown in chapter 19, when carried in bulk.

 

1.1.2    Unless expressly provided otherwise, the Code applies to ships the keels of which are laid or which are at a stage at which:

 

.1        construction identifiable with the ship begins; and

 

.2        assembly of that ship has commenced comprising at least 50 tonnes or 1 % of the estimated mass of all structural material, whichever is less;

 

on or after 1 July 1998. Ships constructed before 1 July 1998 are to comply with resolution MSC.5(48) adopted on 17 June 1983 subject to amendments by resolution MSC.30(61) adopted on 11 December 1992.

 

1.1.3    A ship, irrespective of the date of construction, which is converted to a gas carrier on or after 1 July 1998, should be treated as a gas carrier constructed on the date on which such conversion commences.

 

1.1.4.1 When cargo tanks contain products for which the Code requires a type 1G ship, neither flammable liquids having a flashpoint of 60°C (closed cup test) or less nor flammable products listed in chapter 19 should be carried in tanks located within the protective zones described in 2.6.1.1.

 

1.1.4.2 Similarly, when cargo tanks contain products for which the Code requires a type 2G/2PG ship, the above-mentioned flammable liquids should not be carried in tanks located within the protective zones described in 2.6.1.2.

 

1.1.4.3 In each case the restriction applies to the protective zones within the longitudinal extent of the hold spaces for the cargo tanks loaded with products for which the Code requires a type 1G or 2G/2PG ship.

 

1.1.4.4 The above-mentioned flammable liquids and products may be carried within these protective zones when the quantity retained in the cargo tanks of products for which the Code requires a type 1G or 2G/2PG ship is solely used for cooling, circulation or fuelling purposes.

 

1.1.5    Except as provided in 1.1.7.1, when it is intended to carry products covered by this

 

Code and products covered by the International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk adopted by the Maritime Safety Committee under the authority of the Assembly of the Organization conferred by resolution A.490(XII), as may be amended by the Organization (IBC Code), the ship should comply with the requirements of both Codes appropriate to the products carried.

 

1.1.6    Where it is proposed to carry products which may be considered to come within the scope of the Code but are not at present designated in chapter 19, the Administrations and the port Administrations involved in such carriage should establish preliminary suitable conditions of carriage based on the principles of the Code and notify the Organization of such conditions.

 

1.1.7.1 The requirements of this Code should take precedence when a ship is designed and constructed for the carriage of the following products:

 

.1        those listed exclusively in chapter 19 of this Code; and

 

.2        one or more of the products which are listed both in this Code and in the International Bulk Chemical Code. These products are marked with an asterisk in column a in the table of chapter 19.

 

1.1.7.2 When a ship is intended exclusively to carry one or more of the products noted in 1.1.7.1.2, the requirements of the International Bulk Chemical Code as amended should apply.

 

1.1.8    Compliance of the ship with the requirements of the International Gas Carrier Code should be shown in the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk provided for in 1.5. Compliance with the amendments to the Code, as appropriate, should also be indicated in the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk.

1.2       Hazards

 

Hazards of gases considered in this Code include fire, toxicity, corrosivity, reactivity, low temperature and pressure.

 

1.3       Definitions

 

Except where expressly provided otherwise, the following definitions apply to the Code. Additional definitions are given in chapter 4.

 

1.3.1    Accommodation spaces are those spaces used for public spaces, corridors, lavatories, cabins, offices, hospitals, cinemas, games and hobbies rooms, barber shops, pantries containing no cooking appliances and similar spaces. Public spaces are those portions of the accommodation which are used for halls, dining rooms, lounges and similar permanently enclosed spaces.

 

1.3.2    "A" class divisions means divisions as defined in regulation II-2/3.3 of the 1983 SOLAS amendments.

 

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

 

1.3.3.2 Port Administration means the appropriate authority of the country in the port of which the ship is loading or unloading.

 

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

 

1.3.5    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) should be measured in metres.

 

1.3.6    Cargo area is that part of the ship which contains the cargo containment system and cargo pump and compressor rooms and includes deck areas over the full length and breadth of the part of the ship over the above-mentioned 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 forwardmost hold space are excluded from the cargo area.

 

1.3.7    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.

 

1.3.8    Cargo control room is a space used in the control of cargo handling operations and complying with the requirements of 3.4.

 

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

 

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

 

1.3.11  Cargo tank is the liquid-tight shell designed to be the primary container of the cargo and includes all such containers whether or not associated with insulation or secondary barriers or both.

 

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

 

1.3.13  Control stations are those spaces in which ships' radio or 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.

 

1.3.14  Flammable products are those identified by an Fin column fin the table of chapter 19.

 

1.3.15  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.

 

1.3.16  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.

 

1.3.17  Gas-dangerous space or zone is:

 

.1        a space in the cargo area which is not arranged or equipped in an approved manner to ensure that its atmosphere is at all times maintained in a gas-safe condition;

 

.2        an enclosed space outside the cargo area through which any piping containing liquid or gaseous products passes, or within which such piping terminates, unless approved arrangements are installed to prevent any escape of product vapour into the atmosphere of that space;

 

.3        a cargo containment system and cargo piping;

 

.4.1     a hold space where cargo is carried in a cargo containment system requiring a secondary barrier;

 

.4.2     a hold space where cargo is carried in a cargo containment system not requiring a secondary barrier;

 

.5        a space separated from a hold space described in .4.1 by a single gastight steel boundary;

 

.6        a cargo pump-room and cargo compressor room;

 

.7        a zone on the open deck, or semi-enclosed space on the open deck, within 3 m of any cargo tank outlet, gas or vapour outlet, cargo pipe flange or cargo valve or of entrances and ventilation openings to cargo pump-rooms and cargo compressor rooms;

 

.8        the 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;

 

.9        a zone within 2.4 m of the outer surface of a cargo containment system where such surface is exposed to the weather;

 

.10      an enclosed or semi-enclosed space in which pipes containing products are located. A space which contains gas detection equipment complying with 13.6.5 and a space utilizing boil-off gas as fuel and complying with chapter 16 are not considered gas-dangerous spaces in this context;

 

.11      a compartment for cargo hoses; or

 

.12      an enclosed or semi-enclosed space having a direct opening into any gas-dangerous space or zone.

 

1.3.18  Gas-safe space is a space other than a gas-dangerous space.

 

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

 

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

 

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

 

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

 

1.3.23  Length (L) means 96% of the total length on a waterline at 85% of the least moulded depth measured from the top of the keel, or the length from the foreside of the stem to the axis of the rudder stock on that 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. The length (L) should be measured in metres.

 

1.3.24  Machinery spaces of category A are those spaces and trunks to such spaces which contain:

 

.1        internal combustion machinery used for main propulsion; or

 

.2        internal coombustion 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.

 

1.3.25  Machinery spaces are all machinery spaces of category A and all 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 trunks to such spaces.

 

1.3.26  MARVS is the maximum allowable relief valve setting of a cargo tank.

 

1.3.27  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 1.8 bar gauge.

 

1.3.28  Organization is the International Maritime Organization (IMO).

 

1.3.29  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.

 

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

 

1.3.30.2 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.

 

1.3.30.3 Recognized standards are applicable international or national standards acceptable to the Administration or standards laid down and maintained by an organization which complies with the standards adopted by the Organization* and which is recognized by the Administration.

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* Refer to the Minimum Standards for Recognized Organizations Acting on Behalf of the Administration, set out in appendix 1 to the Guidelines for the Authorization of Organizations Acting on Behalf of the Administration, adopted by the Organization by resolution A.739(18).

 

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

 

1.3.32  Separate means that a cargo piping system or cargo vent system, for example, is not connected to another cargo piping or cargo vent system. This separation may be achieved by the use of design or operational methods. Operational methods should not be used within a cargo tank and should consist of one of the following types:

 

.1        removing spool pieces or valves and blanking the pipe ends;

 

.2        arrangement of two spectacle flanges in series with provisions for detecting leakage into the pipe between the two spectacle flanges.

 

1.3.33  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.

 

1.3.34  1974 SOLAS Convention means the International Convention for the Safety of Life at Sea, 1974.

 

1.3.35  1983 SOLAS amendments means amendments to the 1974 SOLAS Convention adopted by the Maritime Safety Committee of the Organization at its forty-eighth session on 17 June 1983 by resolution MSC.6(48).

 

1.3.36  Tank cover is the protective structure intended to 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.

 

1.3.37  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.

 

1.3.38  Toxic products are those identified by a T in column f in the table of chapter 19.

 

1.3.39  Vapour pressure is the equilibrium pressure of the saturated vapour above the liquid expressed in bars absolute at a specified temperature.

 

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

 

1.4       Equivalents

 

1.4.1    Where the Code requires that a particular fitting, material, appliance, apparatus, item of equipment or type thereof should be fitted or carried in a ship, or that any particular provision should be made, or any procedure or arrangement should be complied with, the Administration may allow any other fitting, material, appliance, apparatus, item of equipment or type thereof to be fitted or carried, or any other provision, procedure or arrangement to be made in that ship, if it is satisfied by trial thereof or otherwise that such- fitting, material, appliance, apparatus, item of equipment or type thereof or that any particular provision, procedure or arrangement is at least as effective as that required by the Code. However, the Administration may not allow operational methods or procedures to be made an alternative to a particular fitting, material, appliance, apparatus, item of equipment, or type thereof which is prescribed by the Code.

 

1.4.2    When the Administration so allows any fitting, material, appliance, apparatus, item of equipment, or type thereof, or provision, procedure or arrangement to be substituted, it should communicate to the Organization the particulars thereof together with a report on the evidence submitted, so that the Organization may circulate the same to other Contracting Governments to the 1974 SOLAS Convention for the information of their officers.

 

1.5       Surveys and certification

 

1.5.1    Survey procedure

 

1.5.1.1 The survey of ships, so far as regards the enforcement of the provisions of the regulations and the granting of exemptions therefrom, should be carried out by officers of the Administration. The Administration may, however, entrust the surveys either to surveyors nominated for the purpose or to organizations recognized by it.

 

1.5.1.2 The Administration nominating surveyors or recognizing organizations to conduct surveys should, as a minimum, empower any nominated surveyor or recognized organization to:

 

.1        require repairs to a ship; and

 

.2        carry out surveys if requested by the port State authority* concerned.

_____________________

* Port State authority has the meaning as presented in chapter 1, regulation 19, of the 1978 Protocol to the 1974 SOLAS Convention.

 

The Administration should notify the Organization of the specific responsibilities and conditions of the authority delegated to nominated surveyors or recognized organizations for circulation to the Contracting Governments.

 

1.5.1.3 When a nominated surveyor or recognized organization determines that the condition of the ship or its equipment does not correspond substantially with the particulars of the certificate or is such that the ship is not fit to proceed to sea without danger to the ship, or persons on board, such surveyor or organization should immediately ensure that corrective action is taken and should in due course notify the Administration. If such corrective action is not taken the relevant certificate should be withdrawn and the Administration should be notified immediately; and, if the ship is in a port of another Contracting Government, the port State authority concerned should also be notified immediately.

 

1.5.1.4 In every case, the Administration should guarantee the completeness and efficiency of the survey, and should undertake to ensure the necessary arrangements to satisfy this obligation.

 

1.5.2    Survey requirements

 

1.5.2.1 The structure, equipment, fittings, arrangements and material (other than items in respect of which a Cargo Ship Safety Construction Certificate, Cargo Ship Safety Equipment Certificate and Cargo Ship Safety Radiotelegraphy Certificate or Cargo Ship Safety Radiotelephony Certificate is issued) of a gas carrier should be subjected to the following surveys:

 

.1        An initial survey before the ship is put in service or before the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk is issued for the first time, which should include a complete examination of its structure, equipment, fittings, arrangements and material in so far as the ship is covered by the Code. This survey should be such as to ensure that the structure, equipment, fittings, arrangements and material fully comply with the applicable provisions of the Code.

 

.2        A periodical survey at intervals specified by the Administration, but not exceeding five years which should be such as to ensure that the structure, equipment, fittings, arrangements and material comply with the applicable provisions of the Code.

 

.3        A minimum of one intermediate survey during the period of validity of the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk. In cases where only one such intermediate survey is carried out in any one certificate validity period, it should be held not before six months prior to, not later than six months after, the half-way date of the certificate's period of validity. Intermediate surveys should be such as to ensure that the safety equipment, and other equipment, and associated pump and piping systems comply with the applicable provisions of the Code and are in good working order. Such surveys should be endorsed on the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk.

 

.4        A mandatory annual survey within three months before or after the anniversary date of the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk which should include a general examination to ensure that the structure, equipment, fittings, arrangements and materials remain in all respects satisfactory for the service for which the ship is intended. Such a survey should be endorsed in the International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk.

 

.5        An additional survey, either general or partial according to the circumstances, should be made when required after an investigation prescribed in 1.5.3.3, or whenever any important repairs or renewals are made. Such a survey should ensure that the necessary repairs or renewals have been effectively made, that the material and workmanship of such repairs or renewals are satisfactory; and that the ship is fit to proceed to sea without danger to the ship or persons on board.

 

1.5.3    Maintenance of conditions after survey

 

1.5.3.1 The condition of the ship and its equipment should be maintained to conform with the provisions of the Code to ensure that the ship will remain fit to proceed to sea without danger to the ship or persons on board.

 

1.5.3.2 After any survey of the ship under 1.5.2 has been completed, no change should be made in the structure, equipment, fittings, arrangements and material covered by the survey, without the sanction of the Administration, except by direct replacement.

 

1.5.3.3 Whenever an accident occurs to a ship or a defect is discovered, either of which affects the safety of the ship or the efficiency or completeness of its life-saving appliances or other equipment, the master or owner of the ship should report at the earliest opportunity to the Administration, the nominated surveyor or recognized organization responsible for issuing the relevant certificate, who should cause investigations to be initiated to determine whether a survey as required by 1.5.2.1.5 is necessary. If the ship is in a port of another Contracting Government, the master or owner should also report immediately to the port State authority concerned and the nominated surveyor or recognized organization should ascertain that such a report has been made.

 

1.5.4    Issue of certificate

 

1.5.4.1 A certificate called an International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk, the model form of which is set out in the appendix, should be issued after an initial or