When trying to detect bunker fuel concealment, it is important to note the trim and list of a vessel.

The perfect time for bunker quantity measurement is when no cargo and ballast operations are taking place and when the vessel is on even keel with no list.

However, during real-world bunkering operations this is not always practical.

As such it is important to check for list and trim accurately both before and after the soundings.

Take an average trim/list and always use the corrected trim for calculations.