Off-spec bunker alerts at Antwerp and Rotterdam drive rise in fuel-related engine claims

A run of off-specification fuel alerts at major bunkering ports over the past six months is translating into engine damage, towage and insurance claims, with data from testing agencies and P&I clubs pointing to the same problems: excessive catalytic fines, poor stability, high sediment and low flash points. Reports have come from Antwerp, Rotterdam, Houston, Singapore, Hong Kong and Piraeus, among other locations.

Data published by West P&I in September, covering samples tested between April and September 2026, found technical off-specification rates for heavy fuel oil of 46.2% in Antwerp, 41.4% in Norfolk, 38% in the Panama Canal region and 35.5% in Rotterdam. The club also identified elevated sulphur off-spec rates among very low sulphur fuel oil samples in Rotterdam and Antwerp, while cautioning that those sample populations were comparatively small.

What do the claims figures show?

Gard handled more than 70 bunker-related claims between January and May 2026, 50% more than in the same period last year. Almost all involved fuel quality, and some vessels were disabled or needed towage. Testing specialist VPS issued 29 bunker alerts in the first seven months of 2026, with catalytic fines and stability problems accounting for 72% of them, and in August identified the Middle East conflict as a major factor behind both rising bunker prices and declining quality. Lloyd's Register FOBAS has said that fuels meeting routine ISO 8217 specifications can still cause operational problems where unusual blending components or poor compatibility affect handling and treatment.

In July, alerts covered high abrasive content in heavy fuel oil supplied in Houston and the Amsterdam-Rotterdam-Antwerp region, severe stability concerns in Piraeus, high sediment in Las Palmas and low flash point fuels in Hong Kong and Singapore.

Why is quality slipping?

David Fuhlbrügge, joint managing director of German testing equipment supplier CM Technologies, links part of the decline to supply chain disruption. "Although conflicts cannot be directly blamed for individual cases of contaminated or off-specification fuel, changes in the availability and sourcing of blending components are important factors shipmanagers need to consider when managing bunker quality," he said.

He said the risk does not end once a delivery passes its first laboratory check, because batches that are stable on their own can prove incompatible when stored or mixed on board. "Catalytic fines are particularly damaging if they are not adequately removed during fuel treatment. The abrasive particles can accelerate wear in fuel injection equipment, cylinder liners and piston rings, potentially shortening component life and increasing maintenance requirements," Fuhlbrügge said.

This story is part of the Maritime Briefing of 29 October 2026.