LR warns ISO-compliant fuels are increasingly causing operational problems

July 15 ------ Lloyd’s Register (LR) has warned that routine fuel quality checks may no longer be enough to identify emerging risks, as some bunker fuels pass standard ISO 8217 testing while concealing stability, compatibility and performance issues.

In its latest Fuel Oil Bunker Analysis and Advisory Service (FOBAS) Fuel Quality Report, covering the first half of 2026 (H1 2026), LR highlights that off-specification fuels remain a persistent concern for the maritime industry. However, the most disruptive cases are increasingly linked to fuels that technically meet specifications but later reveal operational risks during use.

Investigations have found that some compliant fuels contain unconventional blend components or exhibit poor stability and compatibility characteristics that are not detected through routine testing, requiring deeper forensic analysis to identify the underlying causes.

Several recent incidents have highlighted the growing concern. In March and April, multiple vessels experienced operational problems after taking on fuel at a major bunkering hub. Subsequent analysis found elevated levels of Estonian shale oil in many of the affected fuels, with concentrations estimated in some cases at around 10–15%. While shale oil is recognized as an acceptable blending component under ISO 8217, LR’s FOBAS investigations found that higher concentrations may contribute to fuel instability, potentially disrupting critical onboard systems including filters, separators and fuel pumps.

The report also shows that fuel quality variability remains stubbornly high. Off-specification cases remained elevated throughout the first six months of 2026, suggesting that quality issues are no longer isolated events but a more persistent feature of today’s marine fuel supply chain. The most common recurring issues included Sulphur exceedances, excessive water content, sediment and stability problems, elevated catalytic fines, sodium contamination and low flash point distillate fuels.

At the same time, biofuels (especially FAME blends) are continuing to grow without being a primary source of quality issues. Where issues occurred in blended fuels, they were generally associated with the conventional VLSFO component rather than the FAME fraction. "The findings from our latest report show that fuel quality risk is evolving. The challenge is no longer simply identifying fuels that fail specification. Increasingly, operators are encountering fuels that meet the required limits but still create operational difficulties once they are stored, handled and used onboard," said Murray Kirkwood, Fuel Specialist Consultant, Lloyd’s Register.

The findings underscore the need for ship operators to adopt a more proactive approach to fuel management as marine fuels become increasingly diverse and the risks become harder to detect through conventional compliance testing alone. "As fuel blending becomes more complex, the distinction that matters is increasingly not between on-spec and off-spec fuel, but between fuels that are operationally resilient and fuels that are operationally fragile. Understanding that difference is becoming essential for shipowners and operators," Kirkwood concluded.

Source: safety4sea.com