ClassNK Grants First Accreditation for Ammonia Machinery Room Safety on New Gas Carrier

The world’s first accreditation for “Machinery Room Safety for Ammonia” (MRS) will be granted by ClassNK for the ammonia-fueled medium gas carrier (AFMGC) being developed by a consortium including Nippon Yusen Kabushiki Kaisha (NYK) and Nihon Shipyard Co., Ltd. (NSY). MRS is a Class notation that signifies a ship is equipped with exceptional safety measures for handling ammonia in the machinery room, meeting the highest safety standards for ammonia-fueled ships. The consortium aims to deliver the AFMGC by the end of November 2026 under Japan’s Green Innovation Fund Project.

One of the key challenges faced in the development of the ammonia-fueled ship is ensuring safety in the machinery room to protect the crew from toxicity. Measures such as designing to prevent ammonia leakage from piping and tanks are crucial for crew safety. The consortium, with input from NYK’s engineers, has conducted risk assessments and implemented safety measures to achieve the highest level of safety. ClassNK has reviewed the risk assessments and safety measures to ensure compliance with the guidelines for ammonia-fueled ships.

To receive the MRS notation, ships must meet the minimum design requirements for safely using ammonia on board as regulated by ClassNK. Ships must also satisfy optional functional requirements to minimize personal exposure to leaking ammonia in the machinery room. The consortium is focused on further developing the vessel, creating operation manuals, and enhancing safety for ammonia-fueled ships through technical expertise and collaboration among consortium members. Delivery of the AFMGC is targeted for November 2026, with a commitment to improving safety standards for ammonia-fueled ships.

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