ClassNK has released the ‘Guidelines for Liquefied Hydrogen Carriers (Edition 3.0)’, which cover essential details to examine the safety of liquefied hydrogen carriers to spur related technological developments.

To construct a supply chain for hydrogen, which is expected to be a clean energy source in a decarbonized society, the development of liquefied hydrogen carriers that enable large-scale and efficient transportation is progressing actively.

IMO has worked on establishing safety requirements for liquefied hydrogen carriers that must keep cargo at an extremely low temperature of minus 253 degrees Celsius, and ‘Interim Recommendations for Carriage of Liquefied Hydrogen in Bulk’ was adopted in 2016. Subsequent development of liquefied hydrogen carriers led to the construction project of a larger-scale liquefied hydrogen carrier with cargo containment systems of different designs from a prototype liquefied hydrogen carrier. In response to this, at the IMO, discussions for the revision of the interim recommendations have been underway since 2021 and ClassNK has been contributing to these discussions as an expert on the conventions and regulations.

In light of the revised interim recommendations*1 being adopted, ClassNK has updated the guidelines as edition 3.0, reflecting the changes in the interim recommendations and the knowledge gained through related projects. In this update, new safety requirements for cargo containment systems with different designs from an existing prototype liquefied hydrogen carrier were added, and the guidelines’ structure was reformed in anticipation of a future expansion of the applicable scope. Furthermore, to clarify the selection criteria for metallic materials suitable for liquid hydrogen carriers, an annex of guidance for the selection of metallic materials for hydrogen equipment was also newly implemented.

It is believed that the safety of liquid hydrogen carriers is adequately ensured through compliance with each safety requirement and implementation of safety measures based on risk assessment, in accordance with the provisions of the guidelines.

The guidelines are available to download via ‘Guidelines’ of My Page on ClassNK’s website after registration. https://www.classnk.or.jp/account/en/Rules_Guidance/ssl/guidelines.aspx

*1 MSC. 565(108) ‘Revised Interim Recommendations for Carriage of Liquefied Hydrogen in Bulk’

Source: ClassNK