ClassNK to grant ‘world’s first’ MRS accreditation for ammonia-fueled ammonia gas carrier

Japanese classification society ClassNK will award what is said to be the world’s first accreditation for Machinery Room Safety for Ammonia (MRS) to the ammonia-fueled medium gas carrier (AFMGC) currently under development by a consortium that includes NYK, Nihon Shipyard, Japan Engine Corporation, and IHI Power Systems.

The consortium members finalized contracts to build the world’s first ammonia-fueled medium gas carrier (AFMGC) equipped with Japan-made engines in December 2023 under the Green Innovation Fund Project by Japan’s New Energy and Industrial Technology Development Organization (NEDO).

To be built at the Japan Marine United Corporation (JMU) Ariake Shipyard, the 40,000 cbm type ammonia fuel ammonia carrier is scheduled for delivery in November 2026.

MRS notation to be granted by ClassNK demonstrates that the ship is equipped with excellent ammonia safety measures for the machinery room. It also confirms the vessel meets the highest safety measures under the guidelines for ammonia-fueled ships.

To overcome toxicity, which is one of the biggest challenges in the ship’s development, and obtain the MRS notation, the consortium has conducted a risk assessment reviewed by ClassNK, risk assessments and safety measures from a user’s point of view led by NYK’s engineers, and a study of the ship’s specifications to realize the highest level of safety.

Toward the completion of the vessel in November 2026, the consortium will manufacture the main and auxiliary engines, begin detailed studies for the vessel’s construction, and prepare an operation manual for actual operation.

Japan Engine Corporation will be in charge of the ship’s main engine, producing ammonia fuel dual-fuel two-stroke engine, while IHI Power System will provide the auxiliary engine.

After the ship is completed, the consortium will continue to operate the vessel for demonstration purposes to confirm the vessel’s performance, including environmental friendliness and the practicality of the operation manual, and to provide user feedback to shipbuilders and marine equipment manufacturers for further improvements.