Oil record book
All Cargo vessels where MARPOL Convention is applicable must have an oil record book where the chief engineer will record all oil or sludge transfers and discharges within the vessel. This is necessary in order for authorities to be able to monitor if a vessel's crew has performed any illegal oil discharges at sea.
Oil Record Book Coding
In every entry Chief Engineer must record tank number, location, type of oil, description of operation, and quantity. For every operation a combined numerical and letter coding is applied. MEPC.187(59) describes the codes applicable as from 1 January 2011. Also comparison tables between older Oil Record Book coding with MEPC.187(59) are available in the web.
According with revised MEPC.1/Circ736/Rev.1 MEPC.1/Circ736/Rev.1 issued 25 August 2011 additional amendments to Oil Record Book entries have been implemented by IMO.