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 properly disposed of their oil discharges at sea.

Each oil tanker of 150 gross tons and above, ship of 400 gross tons and above other than an oil tanker, and manned fixed or floating drilling rig or other platform shall maintain an Oil Record Book Part I (Machinery Space Operations). An oil tanker of 150 gross tons and above or a non oil tanker that carries 200 meters or more of oil in bulk, shall also maintain an Oil Record Book II (Cargo/Ballast Operation).

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, issued 25 August 2011, additional amendments to Oil Record Book entries have been implemented by IMO.

The first part of the Oil Record Book deals with machinery space operations for all ships. The second part of the Oil Record Book is for cargo/ballast operations and this part only needs to be filled out by crew members aboard oil tankers.

Entries shall be made in the Oil Record Book on each occasion, on a tank to tank basis if appropriate, whenever any of the following machinery space operations take place on any ship to which this section applies—

(1) Ballasting or cleaning of fuel oil tanks;

(2) Discharge of ballast containing an oily mixture or cleaning water from fuel oil tanks;

(3) Disposal of oil residue; and

(4) Discharge overboard or disposal otherwise of bilge water that has accumulated in machinery spaces.

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