4.3 CARGO TRANSFERS DURING THE VOYAGE

During the voyage, regular checks of the cargo tank ullages should be made and recorded. Tank bottom water should not be drained or stripped, especially not overboard (it is a violation of the International convention on the dumping of wastes at sea, 1972 to do so).
If it becomes necessary to trim the ship by transferring cargo, the owners and charterers should be advised, explaining the reasons. A detailed written procedure for the transfer, including designation of all tanks, pipelines and valves involved should be drawn up. Before and after the transfer ullages of all cargo tanks must be recorded. Take particular care to verify that sea valves are closed and sealed before the transfer. Record the seal numbers and all essential transfer times and actions in the log. Note the vessel motion and the possible effect on the ullages. The minimum number of tanks should be used to achieve the desired trim or stress reduction.
Under MARPOL 73/78. Regulation 20 (2) (ii), any internal transfer of oil cargo during the voyage must be recorded in the oil record book.