Consumption must be correct, so if bunker “mismatch” is due to fuel meter calibration issues or imprecise consumption reporting, the consumption must be corrected on all voyages that are affected.
If the bunker “mismatch” is due to e.g. water or air bubbles in a bunker, then a bunker correction can be created. This is done by adding a Bunker Report line with negative Mass. This is exactly the same as if you do a de-bunker. For BDN based fuel consumption and ROB reporting the “de-bunkering” of fuels as records in the Bunker Report are described in the documentation for BDN based reporting in OVD.
If one finds out that consumption is over- or under-reported during a voyage leg, it is permitted to add a “correction” consumption, positive or negative, on or prior to the arrival event.
Corrections shall be properly associated with fuel type or Bunker report as well as consumer (including allocations, if applicable).
In any case, it is important that aggregated consumption (including corrections) is accurate per voyage leg.
If a voyage leg is crossing a leg break, i.e, any period change like year end, flag change or change of owner, or a month or commercial break for DNV’s Emissions Connect service, and the consumption/emissions data shall be shared for each part of the leg individually, the correction shall be distributed appropriately on each part of the leg. This is to avoid
that only one part of the leg will receive all the corrections.
Figure 1 : Example on how to correct an observed bunker discrepancy due to impresise consumption reporting in the past. The example shows a situation where a bunker survey "found" some fuel (orange ROB). The fuel
discrepancy must be distributed as Fuel Oil Consumption adjustments on the voyage legs and, furthermore, on the leg parts. Leg parts are part of a voyage leg, introduced by voyage breaks like any period change like year end, flag change or change of owner, or a month or commercial break for DNV’s Emissions Connect service.
Fuel Oil Consumption adjustments can yield negative consumption on a single event, which are accepted by DNV as long as the leg consumption is greater than 0. ROBs at the end of the Verification period and for Emissions Connect at the end of the Leg part must be corrected, too
Article based on DNV / veracity guidance. For other verifiers different rules may apply.