RESOLUTION MSC.391(95)

 

 (adopted on 11 June 2015)

 

ADOPTION OF THE INTERNATIONAL CODE OF SAFETY FOR SHIPS USING GASES

OR OTHER LOW-FLASHPOINT FUELS (IGF CODE)

 

 

THE MARITIME SAFETY COMMITTEE,

 

RECALLING Article 28(b) of the Convention on the International Maritime Organization concerning the function of the Committee,

 

RECOGNIZING the need for a mandatory code for ships using gases or other low-flashpoint fuels,

 

NOTING resolution MSC.392(95), by which it adopted, inter alia, amendments to chapters II-1,II-2 and the appendix to the annex of the International Convention for the Safety of Life at Sea, 1974 ("the Convention"), to make the provisions of the International Code of Safety for Ships using Gases or other Low-flashpoint Fuels (IGF Code) mandatory under the Convention,

 

HAVING CONSIDERED, at its ninety-fifth session, the draft International Code of Safety for Ships using Gases or other Low-flashpoint Fuels,

 

1          ADOPTS the IGF Code, the text of which is set out in the annex to the present resolution;

 

2          INVITES Contracting Governments to the Convention to note that the IGF Code will take effect on 1 January 2017 upon entry into force of amendments to chapters II-1, II-2 and the appendix to the annex of the Convention;

 

3          INVITES ALSO Contracting Governments to consider the voluntary application of the IGF Code, as far as practicable, to cargo ships of less than 500 gross tonnage using gases or other low-flashpoint fuels;

 

4          RECOGNIZES that requirements for additional low-flashpoint fuels will be added to the IGF Code, as and when they are developed by the Organization;

 

5          REQUESTS the Secretary-General of the Organization to transmit certified copies of the present resolution and the text of the IGF Code, contained in the annex, to all Contracting Governments to the Convention;

 

6          REQUESTS ALSO the Secretary-General of the Organization to transmit copies of the present resolution and the text of the IGF Code contained in the annex to all Members of the Organization which are not Contracting Governments to the SOLAS Convention.

 

 

ANNEX

 

INTERNATIONAL CODE OF SAFETY FOR SHIPS USING GASES OR OTHER LOW-FLASHPOINT FUELS (IGF CODE)

 

1          PREAMBLE

 

The purpose of this Code is to provide an international standard for ships using low-flashpoint fuel, other than ships covered by the IGC Code.

 

The basic philosophy of this Code is to provide mandatory provisions for the arrangement, installation, control and monitoring of machinery, equipment and systems using low-flashpoint fuel to minimize the risk to the ship, its crew and the environment, having regard to the nature of the fuels involved.

 

Throughout the development of this Code it was recognized that it must be based upon sound naval architectural and engineering principles and the best understanding available of current operational experience, field data and research and development. Due to the rapidly evolving new fuels technology, the Organization will periodically review this Code, taking into account both experience and technical developments.

 

This Code addresses all areas that need special consideration for the usage of the low-flashpoint fuel. The basic philosophy of the IGF Code considers the goal based approach (MSC.1/Circ.1394). Therefore, goals and functional requirements were specified for each section forming the basis for the design, construction and operation.

 

The current version of this Code includes regulations to meet the functional requirements for natural gas fuel. Regulations for other low-flashpoint fuels will be added to this Code as, and when, they are developed by the Organization.

 

In the meantime, for other low-flashpoint fuels, compliance with the functional requirements of this Code must be demonstrated through alternative design.

 

 

PART A

 

2          GENERAL

 

2.1 Application

 

Unless expressly provided otherwise this Code applies to ships to which part G of SOLAS chapter II-1 applies.

 

2.2 Definitions

 

Unless otherwise stated below, definitions are as defined in SOLAS chapter II-2.

 

2.2.1 Accident means an uncontrolled event that may entail the loss of human life, personal injuries, environmental damage or the loss of assets and financial interests.

 

2.2.2 Breadth (B) means the greatest moulded breadth of the ship at or below the deepest draught (summer load line draught) (refer to SOLAS regulation II-1/2.8).

 

2.2.3 Bunkering means the transfer of liquid or gaseous fuel from land based or floating facilities into a ships' permanent tanks or connection of portable tanks to the fuel supply system.

 

2.2.4 Certified safe type means electrical equipment that is certified safe by the relevant authorities recognized by the Administration for operation in a flammable atmosphere based on a recognized standard.¹

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¹     Refer to IEC 60079 series, Explosive atmospheres and IEC 60092-502:1999 Electrical Installations in  Ships – Tankers – Special Features.

 

2.2.5 CNG means compressed natural gas (see also 2.2.26).

 

2.2.6 Control station means those spaces defined in SOLAS chapter II-2 and additionally for this Code, the engine control room.

 

2.2.7 Design temperature for selection of materials is the minimum temperature at which liquefied gas fuel may be loaded or transported in the liquefied gas fuel tanks.

 

2.2.8 Design vapour pressure "P₀" is the maximum gauge pressure, at the top of the tank, to be used in the design of the tank.

 

2.2.9 Double block and bleed valve means a set of two valves in series in a pipe and a third valve enabling the pressure release from the pipe between those two valves. The arrangement may also consist of a two-way valve and a closing valve instead of three separate valves.

 

2.2.10 Dual fuel engines means engines that employ fuel covered by this Code (with pilot fuel) and oil fuel. Oil fuels may include distillate and residual fuels.

 

2.2.11 Enclosed space means any space within which, in the absence of artificial ventilation, the ventilation will be limited and any explosive atmosphere will not be dispersed naturally.²

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²   See also definition in IEC 60092-502:1999.

 

2.2.12 ESD means emergency shutdown.

 

2.2.13 Explosion means a deflagration event of uncontrolled combustion.

 

2.2.14 Explosion pressure relief means measures provided to prevent the explosion pressure in a container or an enclosed space exceeding the maximum overpressure the container or space is designed for, by releasing the overpressure through designated openings.

 

2.2.15 Fuel containment system is the arrangement for the storage of fuel including tank connections. It includes 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 fuel storage hold space.

 

The spaces around the fuel tank are defined as follows:

.1 Fuel storage hold space is the space enclosed by the ship's structure in which a fuel containment system is situated. If tank connections are located in the fuel storage hold space, it will also be a tank connection space;

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

.3 Tank connection space is a space surrounding all tank connections and tank valves that is required for tanks with such connections in enclosed spaces.

2.2.16 Filling limit (FL) means the maximum liquid volume in a fuel tank relative to the total tank volume when the liquid fuel has reached the reference temperature.

 

2.2.17 Fuel preparation room means any space containing pumps, compressors and/or vaporizers for fuel preparation purposes.

 

2.2.18 Gas means a fluid having a vapour pressure exceeding 0.28 MPa absolute at a temperature of 37.8°C.

 

2.2.19 Gas consumer means any unit within the ship using gas as a fuel.

 

2.2.20 Gas only engine means an engine capable of operating only on gas, and not able to switch over to operation on any other type of fuel.

 

2.2.21 Hazardous area means an area in which an explosive gas atmosphere is or may be expected to be present, in quantities such as to require special precautions for the construction, installation and use of equipment.

 

2.2.22 High pressure means a maximum working pressure greater than 1.0 MPa.

 

2.2.23 Independent tanks are self-supporting, do not form part of the ship's hull and are not essential to the hull strength.

 

2.2.24 LEL means the lower explosive limit.

 

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

 

2.2.26 LNG means liquefied natural gas.

 

2.2.27 Loading limit (LL) means the maximum allowable liquid volume relative to the tank volume to which the tank may be loaded.

 

2.2.28 Low-flashpoint fuel means gaseous or liquid fuel having a flashpoint lower than otherwise permitted under paragraph 2.1.1 of SOLAS regulation II-2/4.

 

2.2.29 MARVS means the maximum allowable relief valve setting.

 

2.2.30 MAWP means the maximum allowable working pressure of a system component or tank.

 

2.2.31 Membrane tanks are non-self-supporting tanks that consist of a thin liquid and gas tight layer (membrane) supported through insulation by the adjacent hull structure.

 

2.2.32 Multi-fuel engines means engines that can use two or more different fuels that are separate from each other.

 

2.2.33 Non-hazardous area means an area in which an explosive gas atmosphere is not expected to be present in quantities such as to require special precautions for the construction, installation and use of equipment.

 

2.2.34 Open deck means a deck having no significant fire risk that at least is open on both ends/sides, or is open on one end and is provided with adequate natural ventilation that is effective over the entire length of the deck through permanent openings distributed in the side plating or deckhead.

 

2.2.35 Risk is an expression for the combination of the likelihood and the severity of the consequences.

 

2.2.36 Reference temperature means the temperature corresponding to the vapour pressure of the fuel in a fuel tank at the set pressure of the pressure relief valves (PRVs).

 

2.2.37 Secondary barrier is the liquid-resisting outer element of a fuel containment system designed to afford temporary containment of any envisaged leakage of liquid fuel through the primary barrier and to prevent the lowering of the temperature of the ship's structure to an unsafe level.

 

2.2.38 Semi-enclosed space means a space where the natural conditions of ventilation are notably different from those on open deck due to the presence of structure such as roofs, windbreaks and bulkheads and which are so arranged that dispersion of gas may not occur.³

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³  Refer also to IEC 60092-502:1999 Electrical Installations in Ships – Tankers – Special Features.

 

2.2.39 Source of release means a point or location from which a gas, vapour, mist or liquid may be released into the atmosphere so that an explosive atmosphere could be formed.

 

2.2.40 Unacceptable loss of power means that it is not possible to sustain or restore normal operation of the propulsion machinery in the event of one of the essential auxiliaries becoming inoperative, in accordance with SOLAS regulation II-1/26.3.

 

2.2.41 Vapour pressure is the equilibrium pressure of the saturated vapour above the liquid, expressed in MPa absolute at a specified temperature.

 

2.3 Alternative design

 

2.3.1 This Code contains functional requirements for all appliances and arrangements related to the usage of low-flashpoint fuels.

 

2.3.2 Fuels, appliances and arrangements of low-flashpoint fuel systems may either:

.1 deviate from those set out in this Code, or

.2 be designed for use of a fuel not specifically addressed in this Code.

Such fuels, appliances and arrangements can be used provided that these meet the intent of the goal and functional requirements concerned and provide an equivalent level of safety of the relevant chapters.

 

2.3.3 The equivalence of the alternative design shall be demonstrated as specified in SOLAS regulation II-1/55 and approved by the Administration. However, the Administration shall not allow operational methods or procedures to be applied as an alternative to a particular fitting, material, appliance, apparatus, item of equipment, or type thereof which is prescribed by this Code.

 

3          GOAL AND FUNCTIONAL REQUIREMENTS

 

3.1 Goal

 

The goal of this Code is to provide for safe and environmentally-friendly design, construction and operation of ships and in particular their installations of systems for propulsion machinery, auxiliary power generation machinery and/or other purpose machinery using gas or low-flashpoint fuel as fuel.

 

3.2 Functional requirements

 

3.2.1 The safety, reliability and dependability of the systems shall be equivalent to that achieved with new and comparable conventional oil-fuelled main and auxiliary machinery.

 

3.2.2 The probability and consequences of fuel-related hazards shall be limited to a minimum through arrangement and system design, such as ventilation, detection and safety actions. In the event of gas leakage or failure of the risk reducing measures, necessary safety actions shall be initiated.

 

3.2.3 The design philosophy shall ensure that risk reducing measures and safety actions for the gas fuel installation do not lead to an unacceptable loss of power.

 

3.2.4 Hazardous areas shall be restricted, as far as practicable, to minimize the potential risks that might affect the safety of the ship, persons on board, and equipment.

 

3.2.5 Equipment installed in hazardous areas shall be minimized to that required for operational purposes and shall be suitably and appropriately certified.

 

3.2.6 Unintended accumulation of explosive, flammable or toxic gas concentrations shall be prevented.

 

3.2.7 System components shall be protected against external damages.

 

3.2.8 Sources of ignition in hazardous areas shall be minimized to reduce the probability of explosions.

 

3.2.9 It shall be arranged for safe and suitable fuel supply, storage and bunkering arrangements capable of receiving and containing the fuel in the required state without leakage. Other than when necessary for safety reasons, the system shall be designed to prevent venting under all normal operating conditions including idle periods.

 

3.2.10 Piping systems, containment and over-pressure relief arrangements that are of suitable design, construction and installation for their intended application shall be provided.

 

3.2.11 Machinery, systems and components shall be designed, constructed, installed, operated, maintained and protected to ensure safe and reliable operation.

 

3.2.12 Fuel containment system and machinery spaces containing source that might release gas into the space shall be arranged and located such that a fire or explosion in either will not lead to an unacceptable loss of power or render equipment in other compartments inoperable.

 

3.2.13 Suitable control, alarm, monitoring and shutdown systems shall be provided to ensure safe and reliable operation.

 

3.2.14 Fixed gas detection suitable for all spaces and areas concerned shall be arranged.

 

3.2.15 Fire detection, protection and extinction measures appropriate to the hazards concerned shall be provided.

 

3.2.16 Commissioning, trials and maintenance of fuel systems and gas utilization machinery shall satisfy the goal in terms of safety, availability and reliability.

 

3.2.17 The technical documentation shall permit an assessment of the compliance of the system and its components with the applicable rules, guidelines, design standards used and the principles related to safety, availability, maintainability and reliability.

 

3.2.18 A single failure in a technical system or component shall not lead to an unsafe or unreliable situation.

 

4          GENERAL REQUIREMENTS

 

4.1 Goal

 

The goal of this chapter is to ensure that the necessary assessments of the risks involved are carried out in order to eliminate or mitigate any adverse effect to the persons on board, the environment or the ship.

 

4.2 Risk assessment

 

4.2.1 A risk assessment shall be conducted to ensure that risks arising from the use of low-flashpoint fuels affecting persons on board, the environment, the structural strength or the integrity of the ship are addressed. Consideration shall be given to the hazards associated with physical layout, operation and maintenance, following any reasonably foreseeable failure.

 

4.2.2 For ships to which part A-1 applies, the risk assessment required by 4.2.1 need only be conducted where explicitly required by paragraphs 5.10.5, 5.12.3, 6.4.1.1, 6.4.15.4.7.2, 8.3.1.1, 13.4.1, 13.7 and 15.8.1.10 as well as by paragraphs 4.4 and 6.8 of the annex.

 

 

4.2.3 The risks shall be analysed using acceptable and recognized risk analysis techniques, and loss of function, component damage, fire, explosion and electric shock shall as a minimum be considered. The analysis shall ensure that risks are eliminated wherever possible. Risks which cannot be eliminated shall be mitigated as necessary. Details of risks, and the means by which they are mitigated, shall be documented to the satisfaction of the Administration.

 

4.3 Limitation of explosion consequences

 

An explosion in any space containing any potential sources of release⁴ and potential ignition sources shall not:

_______________________

⁴  Double wall fuel pipes are not considered as potential sources of release.

.1 cause damage to or disrupt the proper functioning of equipment/systems located in any space other than that in which the incident occurs;

.2 damage the ship in such a way that flooding of water below the main deck or any progressive flooding occur;

.3 damage work areas or accommodation in such a way that persons who stay in such areas under normal operating conditions are injured;

.4 disrupt the proper functioning of control stations and switchboard rooms necessary for power distribution;

.5 damage life-saving equipment or associated launching arrangements;

.6 disrupt the proper functioning of firefighting equipment located outside the explosion-damaged space;

.7 affect other areas of the ship in such a way that chain reactions involving, inter alia, cargo, gas and bunker oil may arise; or

.8 prevent persons access to life-saving appliances or impede escape routes.

 

PART A-1

 

SPECIFIC REQUIREMENTS FOR SHIPS USING NATURAL GAS AS FUEL

 

 

Fuel in the context of the regulations in this part means natural gas, either in its liquefied or gaseous state.

 

It should be recognized that the composition of natural gas may vary depending on the source of natural gas and the processing of the gas.

 

5          SHIP DESIGN AND ARRANGEMENT

 

5.1 Goal

 

The goal of this chapter is to provide for safe location, space arrangements and mechanical protection of power generation equipment, fuel storage systems, fuel supply equipment and refuelling systems.

 

5.2 Functional requirements

 

5.2.1 This chapter is related to functional requirements in 3.2.1 to 3.2.3, 3.2.5, 3.2.6, 3.2.8, 3.2.12 to 3.2.15 and 3.2.17. In particular the following apply:

.1 the fuel tank(s) shall be located in such a way that the probability for the tank(s) to be damaged following a collision or grounding is reduced to a minimum taking into account the safe operation of the ship and other hazards that may be relevant to the ship;

.2 fuel containment systems, fuel piping and other fuel sources of release shall be so located and arranged that released gas is lead to a safe location in the open air;

.3 the access or other openings to spaces containing fuel sources of release shall be so arranged that flammable, asphyxiating or toxic gas cannot escape to spaces that are not designed for the presence of such gases

.4 fuel piping shall be protected against mechanical damage;

.5 the propulsion and fuel supply system shall be so designed that safety actions after any gas leakage do not lead to an unacceptable loss of power; and

.6 the probability of a gas explosion in a machinery space with gas or low-flashpoint fuelled machinery shall be minimized.

 

5.3 Regulations – General

 

5.3.1 Fuel storage tanks shall be protected against mechanical damage.

 

5.3.2 Fuel storage tanks and or equipment located on open deck shall be located to ensure sufficient natural ventilation, so as to prevent accumulation of escaped gas.

 

5.3.3 The fuel tank(s) shall be protected from external damage caused by collision or grounding in the following way:

.1 The fuel tanks shall be located at a minimum distance of B/5 or 11.5 m, whichever is less, measured inboard from the ship side at right angles to the centreline at the level of the summer load line draught;

     where:

B is the greatest moulded breadth of the ship at or below the deepest draught (summer load line draught) (refer to SOLAS regulation II-1/2.8).

.2 The boundaries of each fuel tank shall be taken as the extreme outer longitudinal, transverse and vertical limits of the tank structure including its tank valves.

.3 For independent tanks the protective distance shall be measured to the tank shell (the primary barrier of the tank containment system). For membrane tanks the distance shall be measured to the bulkheads surrounding the tank insulation.

.4 In no case shall the boundary of the fuel tank be located closer to the shell plating or aft terminal of the ship than as follows:

.1 For passenger ships: B/10 but in no case less than 0.8 m. However, this distance need not be greater than B/15 or 2 m whichever is less where the shell plating is located inboard of B/5 or 11.5 m, whichever is less, as required by 5.3.3.1.

.2 For cargo ships:

.1 for Vc below or equal 1,000 m³, 0.8 m;

.2 for 1,000 m³ < Vc < 5,000 m³, 0.75 + Vc x 0.2/4,000 m;

.3 for 5,000 m³ ≤ Vc < 30,000 m³, 0.8 + Vc/25,000 m; and

.4 for Vc ≥ 30,000 m³, 2 m,

where:

Vc corresponds to 100% of the gross design volume of the individual fuel tank at 20°C, including domes and appendages.

.5 The lowermost boundary of the fuel tank(s) shall be located above the minimum distance of B/15 or 2.0 m, whichever is less, measured from the moulded line of the bottom shell plating at the centreline.

.6 For multihull ships the value of B may be specially considered.

.7 The fuel tank(s) shall be abaft a transverse plane at 0.08L measured from the forward perpendicular in accordance with SOLAS regulation II-1/8.1 for passenger ships, and abaft the collision bulkhead for cargo ships.

where:

L is the length as defined in the International Convention on Load Lines (refer to SOLAS regulation II-1/2.5).

.8 For ships with a hull structure providing higher collision and/or grounding resistance, fuel tank location regulations may be specially considered in accordance with section 2.3.

5.3.4 As an alternative to 5.3.3.1 above, the following calculation method may be used to determine the acceptable location of the fuel tanks:

.1  The value f_CN calculated as described in the following shall be less than 0.02 for passenger ships and 0.04 for cargo ships.⁵

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⁵     The value f_CN accounts for collision damages that may occur within a zone limited by the longitudinal projected boundaries of the fuel tank only, and cannot be considered or used as the probability for the fuel tank to become damaged given a collision. The real probability will be higher when accounting for longer damages that include zones forward and aft of the fuel tank.

.2 The f_CN is calculated by the following formulation: