3rd May 2019

In recent months Intertek Lintec has tested a number of fuel oil bunker samples from vessels that have taken fuel in UST LUGA, that have shown significantly elevated levels of Styrene Monomer to be present.

As part of the Lintec Chemical screening program we regularly see fuels being supplied that contain compounds which are not considered to be a natural constituent of marine fuel oil, but MAY be present in very small quantities due to the consequence of processing operations and use of shared pipelines etc…..

The fact that such compounds are not considered to be naturally occurring in marine fuels suggests that their presence does not fall in line with section 5 of the ISO 8217 fuel standard however, were a fuel found to contain these compounds at LOW LEVELS it may be deemed that it does not meet the standard requirements as specified by the ISO 8217 specification, but it may NOT render the fuel unfit for use.

It has been shown that fuels from Western Europe / the Baltic may well contain traces of ethylene cracker residue (pyrolysis gasoline) as this has a been established as a blend / cutter stock and is often characterised by the presence of elevated levels of Styrene and / or DCPD / Di-Hydro DCPD and / or Indene. The presence of compounds such as Styrene, DCPD etc….. were more prevalent with the 1.00% m/m sulphur fuels used for ECA compliance prior to 2015 however, given that this particular fuel has been removed from the supply chain fuels with significantly elevated levels of these components present.

This being the case we have seen, and still do see fuels that contain both Styrene and DCPD being supplied as a result of blending with cutter stocks such as Ethylene Cracker residue.

However, these recent cases have highlighted levels which are significantly higher than previously noted – ranging from approx. 10,000ppm up to 30,000ppm.

At this time several vessels have report operational difficulties, in the form of excessive sludging and filter blockage, when using these fuels.

If your vessel recently bunkered in UST LUGA or the surrounding areas, we would strongly recommend that you have knowledge of the quality of the fuel prior to use.

Ensure that the samples are taken correctly together with the supplier at the custody transfer point (Barge Manifold / Receiving Vessel Manifold) and witnessed by the ship’s crew. The seal numbers of the samples drawn on the basis of the contract of supply must be recorded on the Bunker Delivery Note (BDN).
If you wish to discuss any of the points highlighted in this bunker alert, please feel free to contact our technical team on +44 (0)1325 390183 or email