ClassNK to class Japan’s first hydrogen fueled tugboat TEN-OH built by TSUNEISHI October 22, 2025 International Shipping, Classification Society, Maritime, Shipping, Trending News TOKYO: ClassNK has added Japan’s first hydrogen-fueled tugboat TEN-OH to its register, which is built by TSUNEISHI SHIPBUILDING Co., Ltd. This vessel was developed and build under the ‘Nippon Foundation Zero Emission Ships Project’,