ClassNK will grant the world’s first accreditation for “Machinery Room Safety for Ammonia” (MRS) to the ammonia-fueled medium gas carrier (AFMGC) currently being developed by a consortium that includes Nippon Yusen Kabushiki Kaisha (NYK) and Nihon Shipyard (NSY).
The MRS classification notation signifies that a ship is equipped with exceptional safety measures for ammonia in its machinery room, ensuring compliance with the highest safety standards outlined in the guidelines for ammonia-fueled ships.
The consortium, to which NYK and NSY belong, is targeting the delivery of the AFMGC by the end of November 2026. The vessel’s development is part of the Green Innovation Fund Project, spearheaded by Japan’s New Energy and Industrial Technology Development Organization (NEDO).
One of the major challenges in the ship’s design is mitigating the risks posed by ammonia’s toxicity in the machinery room. Critical safety measures, such as designs to prevent ammonia leaks from piping and tanks, are essential for crew safety.
To address these challenges, the consortium has conducted risk assessments, reviewed by ClassNK, as well as user-focused risk evaluations and safety measures led by NYK’s engineers.
Additionally, the ship’s specifications have been studied to achieve the highest safety standards worldwide.
The guidelines for ammonia-fueled ships issued by ClassNK regulate the minimum design requirements for the safe use of ammonia onboard. To obtain MRS notation, a ship must meet the optional functional requirement to minimize crew exposure to ammonia leaks in the machinery room. This notation is awarded only to vessels that fulfil this requirement and ensure the highest level of safety.
The consortium continues to develop the vessel, create operation manuals for real-world use, and aim for delivery by November 2026.
Furthermore, the consortium is committed to enhancing safety for ammonia-fueled ships through technical expertise and achievements, including MRS accreditation, in collaboration with its members.