46 CFR § 56.50-55 - Bilge pumps.
(a) Self-propelled vessels.
(1) Each self-propelled vessel must be provided with a power-driven pump or pumps connected to the bilge main as required by table 56.50–55(a).
Table 56.50–55(a)—Power Bilge Pumps Required for Self-Propelled Vessels
| Vessel length, in feet | Passenger vessels 1 | Dry-cargo vessels 2 | Tank
vessels |
Mobile offshore drilling units | |||
|---|---|---|---|---|---|---|---|
| International voyages 3 | Ocean, coast-wise and Great Lakes | All other waters | Ocean, coast-wise and Great Lakes | All waters | All waters | All waters | |
| 180′ or more | 4 3 | 4 3 | 2 | 2 | 2 | 2 | 2 |
| Below 180′ and exceeding 65′ | 4 3 | 5 2 | 5 2 | 5 2 | 5 2 | 2 | 2 |
| 65′ or less | 3 | 1 | 1 | 1 | 1 | 1 | |
1 Small passenger vessels under 100 gross tons refer to subpart 182.520 of subchapter T (Small Passenger Vessel) of this chapter.
2 Dry-bulk carriers having ballast pumps connected to the tanks outside the engineroom and to the cargo hold may substitute the appropriate requirements for tank vessels.
3 Not applicable to passenger vessels which do not proceed more than 20 mile from the nearest land, or which are employed in the carriage of large numbers of unberthed passengers in special trades.
4 When the criterion numeral exceeds 30, an additional independent power-driven pump is required. (See part 171 of this chapter for determination of criterion numeral.)
5 Vessels operating on lakes (including Great Lakes), bays, sounds, or rivers where steam is always available, or where a suitable water supply is available from a power-driven pump of adequate pressure and capacity, may substitute siphons or eductors for one of the required power-driven pumps, provided a siphon or eductor is permanently installed in each hold or compartment.
(b) Nonself-propelled vessels.
(1) Ocean going sailing vessels and barges shall be provided with pumps connected to the bilge main as required in table 56.50–55(b)(1).
Table 56.50–55(b)(1)—Bilge Pumps Required for Nonself-Propelled Vessels
| Type of vessel | Waters navigated | Power pumps (1) | Hand pumps |
|---|---|---|---|
| Sailing | Ocean and coastwise | Two | (2) |
| Manned barges | ......do | Two | (2) |
| Manned barges | Other than ocean and coastwise | (3) | (3) |
| Unmanned barges | All waters | (3) | (3) |
| Mobile offshore drilling units | All waters | Two | None. |
1 Where power is always available, independent power bilge pumps shall be installed as required and shall be connected to the bilge main.
2 Efficient hand pumps connected to the bilge main may be substituted for the power pumps. Where there is no common bilge main, one hand pump will be required for each compartment.
3 Suitable hand or power pumps or siphons, portable or fixed, carried either on board the barge or on the towing vessel shall be provided.
(2) The pumps and source of power for operation on oceangoing sailing vessels and barges shall be located above the bulkhead deck or at the highest convenient level which is always accessible.
(3) Each hull of a vessel with more than one hull, such as a catamaran, must meet Table 56.50–55(b).
(c) Capacity of independent power bilge pump. Each power bilge pump must have the capacity to develop a suction velocity of not less than 400 feet per minute through the size of bilge main piping required by § 56.50–50(d)(1) of this part under ordinary conditions; except that, for vessels of less than 65 feet in length not engaged on international voyages, the pump must have a minimum capacity of 25 gallons per minute and need not meet the velocity requirement of this paragraph.
(d) Priming. Suitable means shall be provided for priming centrifugal pumps which are not of the self-priming type.
(e) Location.
(1) For self-propelled vessels, if the engines and boilers are in two or more watertight compartments, the bilge pumps must be distributed throughout these compartments. On other self-propelled vessels and mobile offshore drilling units, the bilge pumps must be in separate compartments to the extent practicable. When the location of bilge pumps in separate watertight compartments is not practicable, alternative arrangements may be submitted for consideration by the Marine Safety Center.
(2) For nonself-propelled vessels requiring two bilge pumps, these pumps, insofar as practicable, shall be located in separate watertight machinery spaces. When the location of bilge pumps in separate watertight compartments is not possible, the Commandant will consider alternate arrangements of the bilge pumps.
(3) The emergency bilge pumps shall not be installed in a passenger ship forward of the collision bulkhead.
(4) Each hull of a vessel with more than one hull must have at least two means for pumping the bilges in each hull. No multi-hulled vessel may operate unless one of these means is available to pump each bilge.
(f) Other pumps. Sanitary, ballast, and general service pumps having the required capacity may be accepted as independent power bilge pumps if fitted with the necessary connections to the bilge pumping system.