(1) The tanker must not be within a special area;
(2) the tanker must be more than 50 nautical miles from the nearest land; (3) the tanker must be proceeding en route; (4) the instantaneous rate of discharge of oil content must not exceed 30 litres per nautical mile; (5) the total quantity of oil discharged into the sea must not exceed, for tankers delivered on or before 31 December 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 December 1979, 1/30, 000 of the total quantity of the particular cargo of which the residue formed a part; and (6) the tanker must have in operation an oil discharge monitoring and control system and a slop tank arrangement. (MARPOL Annex I, reg. 34.1)
