The zero point of each draught scale must lie vertically below the draught scale in a place, parallel to the plane of maximum draught, passing through the lowest point of the hull or of the keel, if any.
The maximum draught level must be so determined as to ensure compliance with the requirements as to the minimum safety distance at the same time, whilst ensuring that this level cannot at any point be higher than the side decks, or, in the absence of side decks, the upper edge of the hull planking or plating. ... The maximum draught level must be indicated by clearly visible indelible draught marks.