Global testing firm Veritas Petroleum Services (VPS) has issued a caution over elevated shale oil-derived components found in very low sulphur fuel oil (VLSFO) recently supplied in Singapore, according to Ship & Bunker.
What the Testing Revealed
As reported by Ship & Bunker, VPS examined approximately 90,000 metric tons of VLSFO delivered during February and March 2026 and identified compounds consistent with Estonian shale oil streams. Such components are associated with fuel destabilisation, which can result in sludge formation and filter blockages aboard vessels.
The tested fuel samples contained phenolic compounds — including resorcinol and alkyl benzenediols — at concentrations ranging from 4,000 to 13,200 parts per million (ppm). Acid numbers across the samples fell between 1.98 and 2.34 mgKOH/g, levels that VPS described as approaching the ISO 8217 limit.
Compliant on Delivery, but Risks May Linger
At the time of VPS’s update, no operational problems had been reported by vessels that received these fuels. Nevertheless, the firm highlighted that delivery compliance does not eliminate the possibility of longer-term consequences. VPS warned that risks including sludge accumulation, purifier fouling, and compromised fuel injection performance could emerge over time.
Recommended Actions for Operators
In light of its findings, VPS called on operators to step up onboard fuel monitoring, apply careful fuel management procedures, and maintain ongoing sampling programmes. The firm also confirmed it would continue tracking the situation as further feedback from vessels comes in.
Gulf Bunkering does not provide operational or security guidance. This article is for informational purposes only. Operators should consult flag state authorities, P&I clubs, and relevant advisories for decisions relating to transit planning.
Sources: Ship & Bunker
