Fuel testing agency Lintec Testing Services says that of the fuel samples it has tested in the last four months, 7.5% exceeded the limit of 1% sulphur content specified under the new Emissions Control Area (ECA) regulations which came into effect on July 1 this year. Previously, the sulphur content limit had been 1.5%. These results are measured in accordance with the ISO 8217 specification for international marine fuels.
Michael Green, technical manager of Lintec, said it was significant, that only 2.5% of samples taken inside the new ECA region have had a sulphur level above 1.06%. “Samples with sulphur levels between 1% and 1.06% can be regarded as being 95% certain to fail the upper specification limit (of 1%) under ISO 4259 guidelines, referenced under ISO 8217 for interpretation of test data. That is that they fall within this ‘grey area’ in terms of single-test results, and would not necessarily be seen as failing the 1% limit.”
Since May 1 this year, 16.5% of Lintec’s fuel oil samples have been from stems ordered to the maximum 1% sulphur limit
Michael Green added: “In accordance with ISO 4259 principles, bunker suppliers will need to use 0.94% sulphur as the blend target if they want to ensure that the fuel they supply will not exceed the 1% ECA sulphur limit.”
According to Lintec, both ship operators and bunker suppliers now seem to be well-versed in dealing with sulphur limits, and better prepared for the implications of the new 1% limit than they were when the 1.5% limit first took effect.
There is, however, a discrepancy between sulphur verification procedures endorsed by IMO and those referred to in commercial tests on samples sent by fuel buyers to fuel testing agencies. The IMO requirements, which are meant to inform port state control authorities in the event of compliance testing being conducted on an official MARPOL sample, are more stringent than those detailed in ISO 4259. The IMO requirement is for a minimum of two test results, followed by another two if the average of the first two falls within a grey area, and failure if the final test result exceeds the sulphur limit by as little as 0.01%.
Mr Green said: “Bunker buyers and sellers will have to decide for themselves which procedure they will take into consideration in the event of a borderline sulphur test result.”