TREATIES In such a case the volume of effective buoyancy assumed on the undamaged side shall not be greater than that assumed on the damaged side. (8.) Where it is proposed to fit watertight decks, inner skins or longitudinal bulkheads, watertight or non-watertight, the Adminis- tration shall be satisfied that the safety of the ship will not be di- minished in any respect, particularly having in view the possible listing effect of flooding in way of such structural arrangements. REGULATION VI. Peak and Machinery Space Bulkheads, Shaft Tunnels, &c. Peak and machin- ery space bulkheads, shaft tunnels, etc. Ante, p. 1188. Subdivision load- lines. Assigning, marking, and recording. Ante, p. 1134. (1.) Every ship shall have a forepeak or collision bulkhead, which shall be watertight up to the bulkhead deck. This bulkhead shall be fitted not less than 5 per cent. of the length of the ship, and not more than 10 feet (3.05 metres) plus 5 per cent. of the length of the ship from the forward perpendicular. If the ship has a long forward superstructure, the forepeak bulk- head shall be extended weathertight to the deck next above the bulk- head deck. The extension need not be fitted directly over the bulk- head below, provided it is at least 5 per cent. of the length of the ship from the forward perpendicular, and the part of the bulkhead deck which forms the step is made effectively weathertight. (2.) An afterpeak bulkhead, and bulkheads dividing the machinery space, as defined in Regulation I (8), from the cargo and passenger spaces forward and aft, shall also be fitted and made watertight up to the bulkhead deck. The afterpeak bulkhead may, however, be stopped below the bulkhead deck, provided the degree of safety of the ship as regards subdivision is not thereby diminished. (3.) In all cases stern tubes shall be enclosed in watertight spaces. The stern gland shall be situated within a watertight shaft tunnel or other space of such volume that if flooded by leakage through the stern gland the margin line will not be submerged. REGULATION VII. Assigning, Marking and Recording of Subdivision Loadlines. (1.) The subdivision loadlines assigned and marked under the pro- visions of Article 5 of the Convention shall be recorded in the Safety Certificate, and shall be distinguished by the notation C.1 for the principal passenger condition, and C.2, C.3, &c., for the alternative conditions.