12 General Provisions for Bilge Systems
A vessel shall be provided with a satisfactory arrangement for draining any watertight compartment, other than small buoyancy compartments, under all practicable conditions. Sluice valves shall not be fitted in watertight bulkheads.
13 Bilge piping system
11.1 A vessel of 8m (26 feet) or more in length shall be provided with individual bilge lines and bilge suctions for each watertight compartment, except that the space forward of the collision bulkhead need not be fitted with a bilge suction line when the arrangement of the vessel is such that ordinary leakage may be removed from this compartment by the use of a hand portable bilge pump or other equipment, and such equipment is provided.
13.2 A bilge pipe in a vessel of less than 20m (65 feet) in length shall be not less than 25mm (1 inch) nominal pipe size. A bilge pipe in a vessel of 20m or more (65 feet) in length shall be not less than 40mm (1.5 inches) nominal pipe size. A bilge suction shall be fitted with a suitable strainer having an open area not less than three times the area of the bilge pipe.
13.3 Except when individual pumps are provided for separate spaces, individual bilge suction lines shall be led to a central control point or manifold and provided with a stop valve at the control point or manifold and a non-return valve at some accessible point in the bilge line. A stop non-return valve located at a control point or manifold will meet the requirements for both a stop valve and a non-return valve.
13.4 A bilge pipe piercing the collision bulkhead shall be fitted with a screw-down valve located on the forward side of the collision bulkhead and operate from the weather deck, or, where it is readily accessible under service conditions, a screw-down valve without remote operation may be fitted to the bilge line on the after side of the collision bulkhead.
14 Bilge pumps
14.1 A vessel shall be provided with bilge pumps in accordance with Table IV.14.1. A second power pump is an acceptable alternative to a hand pump where it is supplied by a source of power independent of the fixed power bilge pump. Individual power pumps used for separate spaces are to be controlled from a central control point and shall have a light or other visual means at the control point to indicate operation.
14.2 A portable hand bilge pump shall be—
.1 capable of pumping water, but not necessarily simultaneously, from all watertight compartments; and
.2 provided with suitable suction and discharge hoses capable of reaching the bilges for each watertight compartment.
14.3 Each fixed power bilge pump shall be self-priming. It may be driven off the main engine or other source of power. It shall be permanently connected to the bilge manifold and may also be connected to the fire main. A power bilge pump may also serve as a fire pump provided it meets the requirements of regulation V/7.
14.4 Where two fixed power bilge pumps are installed, they shall be driven by different sources of power. Where one pump is driven off the main engine in a single propulsion engine installation, the other shall be independently driven. In a twin propulsion engine installation, each pump may be driven off a different propulsion engine.
14.5 A submersible electric bilge pump may be used as a power bilge pump required by Table IV.14.1 only on a vessel of less than 20 m (65 feet) in length carrying less than 50 passengers, other than a ferry, provided that—
.1 the pump is listed by Underwriters' Laboratories Inc. or another independent laboratory;
.2 the pump is used to pump out not more than one watertight compartment;
.3 the pump is permanently mounted;
.4 the pump is equipped with a strainer that can be readily inspected and cleaned without removal of the pump;
.5 the pump discharge line is suitably supported;
.6 the opening in the hull for the pump discharge shall be placed so that it is above the waterline when the vessel is heeled and trimmed to 15 degrees and 7½ degrees respectively;
.7 a positive shutoff valve is installed at the hull penetration; and
.8 the capacity of the electrical system, including wiring, and size and number of batteries, is designed to allow all bilge pumps to be operated simultaneously.
14.6 A flexible tube or hose may be used instead of fixed pipe for the discharge line of a submersible electric bilge pump provided the hose or tube does not penetrate any required watertight bulkheads. It shall be of good quality and of substantial construction, suitable for the intended use; and highly resistant to salt water, petroleum oil, heat, and vibration, and shall be located so as to minimize the risk of accidental damage.
14.7 Where a fixed hand pump is used to comply with Table IV.14.1, it shall be permanently connected to the bilge system.
14.8 On a vessel of less than 20m (65 feet) in length, a power driven fire pump required by regulation V/7 may serve as a fixed power bilge pump required by regulation IV/14.1, provided it has the minimum flow rate required by Table IV.14.1.
14.9 On a vessel of 20m or more (65 feet) in length, a power driven fire pump required by regulation V/7 may serve as one of the two fixed power bilge pumps required by regulation IV/14.1, provided it has the minimum flow rate required by Table IV.14.1.
14.10 Where the bilge and fire pump systems are interconnected, the dedicated bilge pump is to be capable of pumping the bilges overboard at the same time as the fire/bilge pump charges the firemain. Stop valves and check valves shall be installed in the piping to isolate the systems during simultaneous operation and prevent possible flooding through the bilge system.
14.11 A catamaran vessel shall be equipped with bilge pumps for each hull, as if each hull is a separate vessel, in accordance with Table IV.14.1, except where—
.1 one dedicated pump is located in each hull;
.2 each dedicated pump is driven by an independent source of power; and
.3 the bilge pumping system is permanently cross-connected between hulls to facilitate pumping of either hull by either bilge pump.
.4 isolating valves shall be fitted within the cross connection to prevent flooding from one hull to another.
15 Bilge high level alarms
15.1 On a vessel 8m (26 feet) or more in length, a visual and audible alarm shall be provided at the operating station to indicate a high water level in each of the following normally unmanned spaces—
.1 a space with a through-hull fitting below the deepest load waterline, such as a lazarette;
.2 a machinery space bilge, bilge well, shaft alley bilge, or other spaces subject to flooding from sea water piping within the space; and
.3 a space with a non-watertight closure, such as a space with a non-watertight hatch on the main deck.
15.2 Vessels constructed of wood shall, in addition to IV/15.1, provide bilge level alarms in all watertight compartments except buoyancy chambers of less than 0.25m3.
15.3 A visual indicator shall be provided at the operating station to indicate when any automatic bilge pump is operating