Section 4 Bilge pumping and drainage systems
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Special Service Craft, July 2022 - Part 15 Piping Systems and Pressure Plant - Chapter 2 Ship Piping Systems - Section 4 Bilge pumping and drainage systems

Section 4 Bilge pumping and drainage systems

Parent topic: Chapter 2 Ship Piping Systems

4.1 General

4.1.1 Arrangements are to be made for draining all watertight compartments other than those intended for permanent storage of fluids. Where drainage is not considered necessary, drainage arrangements may be omitted provided the safety of the craft is not impaired.

4.1.2 Pumping arrangements are to be provided having suctions and means of drainage so arranged that any water within any watertight compartment of the craft or any watertight section of any compartment, can be pumped out through at least one suction under all possible conditions of list and trim in the maximum assumed damage condition.

4.1.3 The bilge pumping system is to be designed to prevent water flowing from one watertight compartment to another.

4.1.4 The necessary valves for controlling the bilge suctions are to be capable of being operated from above the watertight deck.

4.1.5 Where a bilge main is not fitted and a compartment is served by a fixed submersible pump in accordance with Pt 15, Ch 2, 10 Submersible bilge pump arrangements, then an additional emergency means of pumping out the compartment is to be provided, see Pt 15, Ch 2, 6 Emergency bilge drainage.

4.1.6 Small compartments may be drained by individual hand pump suctions.

4.1.7 The intactness of watertight bulkheads is not to be impaired by the fitting of scuppers discharging to machinery spaces or tunnels from adjacent compartments situated below the highest watertight deck.

4.1.8 Any unattended space for which bilge pumping arrangements are required is to be provided with a bilge level alarm.

4.1.9 Where it is intended to carry flammable or toxic liquids in enclosed spaces, the bilge system shall be designed to prevent pumping of such liquids through piping and pumps in machinery or other spaces where a source of ignition may exist.

4.2 Drainage of raft void spaces on multi-hull craft

4.2.1 Where the raft void space is located above the water line in the maximum assumed damage condition, then it may be drained directly overboard through scuppers fitted with non-return valves of approved type.

4.2.2 Raft void spaces which are not located above the water line in the maximum assumed damage condition are to be provided with pumping arrangements in accordance with Pt 15, Ch 2, 4.1 General.

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