Falsifying documentation onboard is one of the techniques used to conceal bunker fuel.
Questionable Tank Sounding (Calibration) Tables
Verify that the sounding tables are approved and endorsed by the Class or Recognised Authority. Having more than one set of sounding book is not uncommon and having the tables modified to their advantage is always a possibility. Inserted pages, corrections, different print/paper type are all indications of tampering.
Sometimes the vessel may have a new calibration table (with the old one being obsolete). This could be following modification of the tanks internal structure during a dry dock repair or simply because the original calibration tables would have been incorrect. Always find out the reason for new calibration table and making sure it's Class Certified.
Incorrect Fuel Densities and Missing BDN Records
Fuel densities given by the Chief Engineer should be verified against Fuel Laboratory Analysis Reports for the most recent bunker stem and if not readily available then densities stated in the BDN (Bunker Delivery Note) should be used.
Since BDN must be retained on board for 3 years from the date of fuel supply and should be readily available for inspection by port state control and relevant authorities (because non- compliance with fuel oil sulphur limits could lead to fines / detention of the vessel) as such there is no excuse for not maintaining a file for previous and current BDNs.
Overstating Fuel Consumption
Verify fuel consumptions for last 30 days or as required from the engine's log book / noon reports / deck log abstracts. Example engine over consumption could be shown due to alleged heavy weather during the voyage or boiler over consumption shown even when the vessel would have been idle at anchorage for significant period of time in hot weather. These are all tell-tale signs of fuel misappropriation.
Oil Record Book (ORB)
ORB should be scrutinized for last sludge / bilge transfer operations; retention of oil residues (sludge); identity and capacities of tanks; records of collection and disposal oil residue to shore facility etc. This will give an idea of the vessel's sludge and waste oil management systems. On many occasions concealed bunkers have been found in waste tanks transferred via an unauthorized connection like a rubber hose!
Kaivan H. Chinoy is the Founder and Principal Marine Surveyor of AVA Marine Group, owners of Petro
Inspect and The Bunker Detectives.