37.—(1) The subdivision load lines assigned and marked on a ship shall be distinguished by the notation C.1 for the principal passenger condition, and C.2, C.3, etc., for the alternative conditions.
(2) A subdivision load line mark shall not in any case be placed above the deepest load line in salt water as determined by the strength of the ship.
(3) The ship shall not in any case be so loaded that when it is in salt water the subdivision load line mark appropriate to the particular condition of service is submerged.