Wash plates and wash bulkheads are, in general, to have an area of perforation not less than 10 percent of the total area of the bulkhead. The perforations are to be so arranged that the efficiency of the bulkheads as a support is not impaired. The plate thickness is to be not less than the structural element from which the wash bulkhead is formed.
The general stiffener requirement for both section modulus and section inertia may be 50 per cent of that required for stiffener members fitted in the bulkheads which form the boundaries of integral tanks.
5.4.4 Collision bulkheads
The scantlings of collision bulkheads are to be not less than as required for integral tank bulkheads.
5.4.5 Gastight bulkheads
Where gastight bulkheads are fitted, the scantling requirements for watertight bulkheads are to be complied with.
5.4.6 Non watertight or partial bulkheads
Where a bulkhead is structural but non watertight the scantlings are in general to be as for watertight bulkheads or equivalent in strength to web frames in the same position. Partial bulkheads that are non-structural are outside the scope of this standard.
5.4.7 Transmission of pillar loads
Bulkheads that are required to act as pillars in way of under-deck girders subjected to concentrated loads and other structures which impart heavy loads are to be suitably strengthened.
