Annex I deals with the prevention of pollution by oil. Ships are not allowed to discharge oily sludge from the combustion of heavy fuel oil into the sea. The discharge of oily bilge water and cargo residues of oil tankers is severely restricted; only very small quantities or strong dilutions are allowed. Oily mixtures and residues normally have to be discharged to port reception facilities. Similar regulations apply to residues from the cargoes of chemical tankers.
According to Annex I, an Oil Record Book has to be kept to record operations involving the disposal of oily residues (from the ship’s machinery space and cargo tanks)

OIL TANKERS OF ALL SIZES
Control of discharge of oil from cargo tank areas including cargo pump room

Within special areas OR outside special areas, within 50 nautical miles (nm) from the nearest land

ANY DISCHARGE IS PROHIBITED, except clean or segregated ballast

Outside special areas, more than 50 nm from the nearest land

ANY DISCHARGE IS PROHIBITED, with the exception of clean or segregated ballast, or except when: the tanker is proceeding en route, and 2. the instantaneous rate of discharge of oil does not exceed 30 litres/nm, and 3. the total quantity of oil discharged into the sea – does not exceed for tankers delivered on or before 31.12.1979 1/15,000 of the total quantity of the particular cargo of which the residue formed a part and – for tankers delivered after 31.12.1979 1/30,000 of the total quantity of the particular cargo of which the residue formed a part, and 4. the tanker has in operation an oil discharge monitoring and control system and a slop tank arrangement as required by regulations 29 and 31, respectively

Special Areas

• Mediterranean Sea area
• Baltic Sea area
• Black Sea area
• Red Sea area
• ‚Gulfs‘ area means the sea area located north-west of the rhumb line between Ras al Hadd and Ras al Faseth
• Gulf of Aden area
• Antarctic area
• North West European waters include the North Sea and its approaches, the Irish Sea and its approaches, the Celtic Sea, the English Channel and its approaches and part of the North East Atlantic immediately to the west of Ireland.
• Oman Area of the Arabian Sea

• Southern South African waters