Gard, one of the world's largest marine insurers, has reported a sharp rise in sulfur-related bunker claims as Chinese authorities step up checks on ships and marine fuel.

The number of cases more than tripled in the first half of 2026 compared with a year earlier, Gard said in an article published on Wednesday. The half-year total also exceeded the number of cases recorded in all of 2025 by about 40%.

The increase comes as the China Maritime Safety Administration (MSA) and local maritime authorities carry out a joint pollution control campaign in the Bohai Sea, the waters off northern China that host one of the country's busiest port clusters. The MSA offices in Tianjin, Hebei, Liaoning and Shandong launched the campaign on June 5, covering major ports including Tianjin, Tangshan, Qinhuangdao, Huanghua, Jinzhou, Yingkou and Longkou.

Checks can include fuel sampling, onboard inspections, and reviews of bunker delivery notes, fuel test reports and fuel management records.

Gard highlighted a recent case in Panjin, where China MSA officers found fuel containing 2.51% sulfur. That reading is about five times the 0.50% global cap on sulfur in ship fuel that has applied outside designated emission control areas since January 2020 under the IMO's MARPOL convention. Initial testing put the level at between 2.5% and 2.7%. The vessel was ordered to stop using the fuel and to submit a disposal plan while the investigation continued.

Ships using fuel that fails to meet Chinese requirements can face fines of RMB 10,000 to RMB 100,000.

Gard urged owners and operators to check fuel quality carefully and to retain bunker samples and documentation in case of inspections or claims, with the Bohai campaign covering both fuel sampling and the paperwork behind it.

Source: Ship & Bunker