Oil Record Book

The Oil Record Book is a mandatory document required under MARPOL Annex I for machinery spaces (Part I) and cargo/ballast operations on tankers (Part II). Every operation involving oil — including bilge water transfer, use of the oily water separator, discharge to sea (if permitted), discharge to port reception facilities, oil transfer operations on tankers, and tank cleaning — must be recorded in the relevant ORB using the prescribed codes and in the prescribed format. The master must sign each completed page. For a chief engineer and deck officer on a tanker, the ORB is a contemporaneous legal record. Port state control inspectors examine it closely for completeness, logical consistency with pump logs, tank soundings, and flow meter readings, and for signs of alteration or fabrication. Prosecutors in several jurisdictions have used inconsistencies in ORB entries as primary evidence in pollution cases, leading to the imprisonment of masters and chief engineers. The burden of proof can in practice shift to the vessel once a pattern of implausible entries is established. ORBs must be kept on board for a minimum of three years after the last entry. Entries must be in ink, and corrections must be made by crossing out the error with a single line, initialling, and writing the correct entry. White-out fluid and erasure are prohibited. Officers must understand that deliberate falsification — recording a separator discharge that was in fact a straight overboard discharge — constitutes a serious criminal offence under most port state enforcement frameworks.