ISO 2020 PAS… To Be or Not To Be? Or Much Ado About Nothing?

By Ara Barsamian, President/CEO, Refinery Automation Institute, LLC
Tuesday October 8, 2019

It is a beautiful day in Copenhagen, and ISO decided to publish the 2020 Publicly Available Specs on the same beautiful September day…

But like Shakespeare's Hamlet, the "PAS" is a puzzle: it is not really a "spec", no numbers…and numbers…TALK!!!

The bunker community was awaiting breathlessly for the magic 2020 specs, but what it got instead is a political document with more "considerations, guidance,…etc."

Hence, like Hamlet's dilemma: what are the specs we need to worry about with 2020 fuels? Any quantification (numbers, that is)?

Among others, I proposed to the ISO WG (working group) to introduce in PAS specs for

  • Asphaltenes (directly responsible for stability and compatibility), e.g. limited to less than 5%
  • Stability and compatibility in the form of Stability Reserve testing (using tests such as  Toluene Equivalence, Peptization power, Flocculation Ratio, etc.) of at least 1.5
  • Aromaticity , of at least 50% or even better, SARA testing (Saturates, Aromatics, Resins, Asphaltenes), which allows us to calculate CII (Colloidal Instability Index), another predictor of stability and compatibility taking into account also the paraffins (from waxy residue used to make bunkers).

These properties allowed us and others to develop algorithms to PREDICT if a blend component or a product is stable and compatible…

But Alas, ISO WG chose to ignore the suggestions, limiting itself to "toothless" considerations. Of course, it the end users, the shipowners, that will suffer the consequences…

To learn more about stability and compatibility of 2020 bunker fuels, you can attend our upcoming course in Houston on October 21 and 22. To register, go to: