1 Owing to the growing global demand for liquefied natural gas (LNG) as an
environment-friendly energy source and the increased construction and operation of
LNG-fuelled ships, the Maritime Safety Committee, at its ninety-sixth session (11 to 20
May 2016), agreed to the need to ensure that cargo and fuel tanks of LNG carriers and
LNG-fuelled ships were safe, and hence tasked the Sub-Committee on Carriage of Cargoes
and Containers with addressing the matter by developing amendments to the IGC and IGF
Codes in order to include high manganese austenitic steel for cryogenic service.
2 The Maritime Safety Committee, at its 100th session (3 to 7 December 2018),
acknowledging the increasing use of high manganese austenitic steel by the industry for
cryogenic service and the need for guidance in this respect, approved the Interim
guidelines on the application of high manganese austenitic steel for cryogenic
service (MSC.1/Circ.1599).
3 The Maritime Safety Committee, at its 102nd session (4 to 11 November 2020), approved
the Revised Interim Guidelines (MSC.1/Circ.1599/Rev.1), prepared by the Sub-Committee on
Carriage of Cargoes and Containers, at its sixth session (9 to 13 September 2019).
4 The Maritime Safety Committee, at its 105th session (20 to 29 April 2022), approved the
Revised Guidelines, as set out in the annex, prepared by the Sub-Committee on Carriage
of Cargoes and Containers, at its seventh session (6 to 10 September 2021).
5 The Committee agreed to keep the Revised Guidelines under review, taking into account
operational experience gained with their application.
6 Member States are invited to bring the Revised Guidelines to the attention of all
parties concerned.
7 This circular supersedes MSC.1/Circ.1599/Rev.1.