a subdivision load line is a waterline used in determining the subdivision of a ship;
(ii)
the deepest subdivision load line is the water line which corresponds to the greatest draught permitted by the subdivision requirements which are applicable;
(b)
the length of the ship is the length measured between perpendiculars taken at the extremities of the deepest subdivision load line;
(c)
the breadth of the ship is the extreme width from outside of frame to outside of frame at or below the deepest subdivision load line;
(d)
the draught is the vertical distance from the moulded base line amidships to the relevant subdivision load line;
(e)
the bulkhead deck is the uppermost deck up to which the transverse watertight bulkheads are carried;
(f)
the margin line is a line drawn at least 76 millimetres below the upper surface of the bulkhead deck at side;
(g)
the permeability of a space is the percentage of that space which can be occupied by water. The volume of a space which extends above the margin line shall be measured only to the height of that line;
(h)
the machinery space is to be taken as extending from the moulded base line to the margin line and between the extreme main transverse watertight bulkheads bounding the spaces containing the main and auxiliary propelling machinery, boilers serving the needs of propulsion, and all permanent coal bunkers. In the case of unusual arrangements, the Director may define the limits of the machinery spaces; and
(i)
in all cases volumes and areas shall be calculated to the moulded lines.