Sounding Correction Guideline
This guideline provides detailed instructions for handling sounding corrections to ensure accurate fuel consumption reporting. It is intended for crew members on board.
Usually a sounding correction event is not needed when all items where correctly reported. This guide will show examples when a souding correction event shall be created in S-Log Recorder and when not.
1. What should the crew do in terms of accurate reporting?
- Imprecise Consumption Reports
Above reason is not accepted according to DNV´s sounding correction guidelines. Crew
should distribute the excessive amount to previous voyage events in order to have the
proper data quality.
i.e Let´s assume there are 30 days between the previous sounding correction event and
above shown sounding correction event. Reported sounding correction is 198mt. Reported
engine running hours are 660 for this period.198/660=0.3mt of extra fuel consumption
reported for every running hour. Therefore, the crew should amend every event for that
period and reduce the consumption according to running hours. Below reported HFO
consumption will be 62.9–(0.3x23)= 56 mt
- Air Bubbles in Bunker
The "air bubble effect" in bunkering refers to the phenomenon where air is unintentionally
introduced into the fuel flow during the bunkering process. This can occur due to various
factors such as improper handling, equipment malfunctions, or high-pressure fuel delivery
systems. The presence of air bubbles in the fuel being measured can lead to inaccuracies in
the reported quantity of bunkered fuel. That is why the above reasons are accepted by
verifier since quantity in BDN and s-log bunkering event should match each other. However,
according to our experience air bubbles do not create huge amount of discrepancy below. If
there is any issue with air bubbles during bunkering, the computed ROB should be higher
than actual ROB. Therefore, below reporting is not proper.
- Bunkering Barge Dispute
Bunkering event should be created based on the received BDN. If there is any discrepancy
due to a dispute with the supplier, this reason can be selected for sounding correction
reporting. In such instances, the vessel manager should reach out to the supplier to obtain
the proper BDN, if feasible.
- Sounding Correction after Every Voyage Completion.
To ensure data quality remains consistent, we recommend measuring the sounding
correction after every arrival. If there is any discrepancy between the actual ROB and the
computed ROB, the Noon Reports for the voyage should be amended rather than creating a
separate sounding correction event.