With the introduction of MARPOL Annex VI, the sulphur content of a particular fuel oil is now often the primary factor in assessing whether or not that fuel oil is acceptable for intended use. However, at present, this issue is complicated by the fact that the Annex’s approach to assessing compliance differs fundamentally from the commercial process under which the fuel oil is ordered and supplied.
There are a number of standard test methods for determining fuel oil sulphur content. For marine fuel oils, the ISO 8754:2003 test method is the reference method both for ISO 8217 and the Annex and therefore this review is written on that basis.
This review concludes that IMO should be invited to re-consider the Annex verification procedure, taking into account the technical facts and the established commercial practice.
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