Summary of amendments to the IGC Code

3.1 The IGC Code applies to gas carriers constructed on or after 1 July 1986. The purpose of the code is to provide an international standard for the safe transport in bulk by sea of liquefied gases, by prescribing the design and construction standards of ships involved in such transport and the equipment they should carry so as to minimise the risk to the ship, its crew and to the environment, having regard to the nature of the products involved. The IGC Code is implemented in the UK by the Merchant Shipping (Carriage of Dangerous Goods and Harmful Substances) (Amendment) Regulations 2024.

3.2 Two sets of amendments to the IGC Code will enter into force in 2026. Firstly, amendments related to the addition of high manganese austenitic steel as a new material used in the construction of the cargo system on gas carriers and, secondly, amendments related to the use of cargoes as fuel for the ship.

High manganese austenitic steel

3.3 Amendments to the IGC Code adopted by resolution MSC.523(106) replace table 6.3 in section 6.4 (Requirements for metallic materials) of the IGC Code. Table 6.3 is headed Plates, Sections and Forgings for Cargo Tanks, Secondary Barriers and Process Pressure Vessels for Design Temperatures Below -55°c and Down to -165°c Maximum Thickness 25 mm and it is replaced in its entirety. The new table 6.3 includes provisions for high manganese austenitic steel.

3.4 Resolution MSC.524(106), approved at the same time as MSC.523(106), makes the same change to Table 7.3 in the International Code of Safety for Ships Using Gases or Other Low-Flashpoint Fuels (the IGF Code).

3.5 This amendment to the IGC Code enters into force internationally on 1 January 2026 and, by way of the ambulatory reference provisions in the Merchant Shipping (Carriage of Dangerous Goods and Harmful Substances) (Amendment) Regulations 2024, enters into force in the UK on the same date.

Use of cargo as fuel

3.6 Separately, amendments to the IGC Code regarding the use of cargo as fuel have been adopted by resolution MSC.566(109). In section 16.9 (Alternative fuels and technologies), paragraph 16.9.2 previously stated that the use of cargoes identified as toxic products was not permitted. This amendment refines paragraph 16.9.2 of the Code, meaning that the IGC Code is now more aligned with the fuels permitted for use under the IGF Code in the drive to decarbonise global shipping and reduce emissions.

3.7 The amended text of 16.9.2 is as follows:

16.9.2 The use of cargoes requiring carriage in type 1G ships, as identified in column “c” in the table of chapter 19, shall not be permitted. If acceptable to the Administration, cargoes identified as toxic products in column “f” which are required to be carried in type 2G/2PG ships in column “c” in the table of chapter 19 may be used as fuel, provided that the same level of safety as natural gas (methane) is ensured in accordance with the relevant provisions of this Code, including those in 1.3, and taking into account the guidelines developed by the Organization, after special consideration has been given by the Administration.

3.8 This amendment to the IGC Code will enter into force internationally on 1 July 2026 and, by way of the ambulatory reference provisions in the Merchant Shipping (Carriage of Dangerous Goods and Harmful Substances) (Amendment) Regulations 2024, enters into force in the UK on the same date.