Section 7 Peak, watertight and deep tank bulkheads

7.1.1 The scantlings of watertight and deep tank bulkheads are to comply with the requirements of Pt 4, Ch 1 General Cargo Ships.

7.1.2 The load head, h ₄, to be used in watertight bulkhead scantlings for passenger ships is, in addition, to comply with the following:

• For watertight bulkhead plating, the distance from a point one-third of the height of the plate above its lower edge to a point 0,91 m above the bulkhead deck at side, or to the deepest intermediate/equilibrium waterline in damaged condition obtained from applicable damage stability calculations, whichever is the greater, see also Figure 3.5.2 Heads for watertight and deep tank bulkheads in Pt 3 Ship Structures (General) and Pt 3, Ch 3, 5.5 Flooded loads.
• For watertight bulkhead stiffeners or girders, the distance from the middle of the effective length to a point 0,91 m above the bulkhead deck at side, or to the deepest intermediate/equilibrium waterline in damaged condition obtained from applicable damage stability calculations, whichever is the greater, see also Figure 3.5.2 Heads for watertight and deep tank bulkheads in Pt 3 Ship Structures (General) and Pt 3, Ch 3, 5.5 Flooded loads.

7.1.3 Partial watertight bulkheads and webs fitted above the bulkhead deck which are to be included in damage stability calculations, are to be assessed as watertight, see Pt 4, Ch 2, 7.1 General 7.1.2.

7.2.1 The thickness of bulkhead plating for peak tanks and deep tanks, other than the collision bulkhead, may be reduced by 0,5 mm, and the modulus of bulkhead stiffeners, swedges, corrugations and girders may, in general, be reduced by 20 per cent from the values required by Pt 4, Ch 1, 9 Bulkheads.