Heatmaster (Nantong) Boiler Co., Ltd. is the Chinese manufacturing arm of Heatmaster BV, a Dutch marine boiler engineering company with its head office in the Port of Rotterdam and additional offices in Shanghai and Spain. The Nantong factory handles production engineering and manufacturing of heating equipment and has grown from a few people at the start to about fifty staff today, marking a ten-year anniversary milestone for the facility. The plant is certified to ISO 9001:2015, and classification societies, shipowners and shipyards routinely attend Factory Acceptance Tests there for equipment they have contracted. The Heatmaster product range covers complete thermal-oil and hot-water boiler systems for ship engine rooms and cargo heating, with steam-heating systems and compact LNG-bunker-vessel cargo-tank pressure-control solutions also engineered in-house; specific shipbuilding references include LNG bunker vessel newbuildings for Avenir LNG at Keppel Nantong Shipyard and for Gazpromneft. About 60 to 70 percent of the parent firm's business is in Asia. The dataset records categories of pressure-vessel inspection and underwater inspection under ABS and ClassNK service-supplier approvals for Heatmaster (Nantong) Boiler Co., Ltd., placing it within the Nantong shipbuilding cluster on the north bank of the Yangtze.