Order No. 268 on classification, transport and discharge of liquid substances carried in bulk.

This Order sets regulations and restrictions to all ships dumping liquid substances in bulk. It does however not apply to warships or other ships owned or operated by a state, as long as the ship is used exclusively for non-commercial purposes. Hazardous liquid substances must be classified in X, Y and Z categories in order to for Marine authorities and other MARPOL convention countries to be notified of the evaluated risks thereof. Definitions are set in article 13 on allowed discharge of residue of X, Y and Z substances when: ships navigate on speed of min. 7 knots or at least 4 knots, if not on own power; the discharge is made below the water line at a rate which does not exceed the permissible speed calculated for the outlet; and the discharge is made at a distance of at least 12 miles from the nearest land and in water depths of less than 25 meters. If a tank having contained Category X substance has been unloaded, it must be cleaned before the ship leaves the harbour
The Order contains 14 Chapters and 3 Annexes; Scope and purpose (1); Definitions (2); Categorization and classification of noxious liquid substances and other substances (3); General provisions of discharge and transport (4); The discharge of substances in Category X (5); The discharge of substances in Category Y and Z (6); Requirements for intake and discharge of ballast water (7); Requirements for discharge (8); Venting of cargo residue (9); Exemption from tank cleaning (10); Use of detergents and additives (11); Penalty (12); Publication of rules (13); Entry into force (14).
Annex 1 - Guidelines for classification of liquid dangerous substances.
Annex 2 - Airing procedures.
Annex 3 - Pre-wash procedures.