46 CFR § 132.120 - Fire pumps.
(a) Except as provided by § 132.100(b) of this subpart, each vessel must be equipped with one self-priming power-driven fire pump capable of delivering a single stream of water from the highest hydrant, through the hose and nozzle at a Pitot-tube pressure of at least 345 kPa (50 psi [pounds per square inch]).
(b) Each fire pump must be fitted on the discharge side with a pressure gauge.
(c) Each fire pump must be fitted on the discharge side with a relief valve set to relieve at either 172 kPa (25 psi) in excess of the pressure necessary to maintain the requirements of paragraph (a) of this section or 862 kPa (125 psi), whichever is greater. The relief valve is optional if the pump is not capable of developing pressure exceeding the greater amount.
(d) If two propulsion engines are installed, the pump required by paragraph (a) of this section may be driven by one of the engines. If only one propulsion engine is installed, the pump must be driven by a source of power independent of the engine.
(e) If two fire pumps are installed, and if one pump remains available for service on the fire main at any time, the other pump may be used for other purposes.
(f) Each fire pump must be capable of providing the quantity of water required to comply with paragraph (a) of this section while meeting any other demands placed on it, as by a branch line connected to the fire main for washing the anchor or the deck.
(g) No branch line may be directly connected to the fire main except for fighting fires or for washing the anchor or the deck. Each discharge line for any other purpose must be clearly marked and must lead from a discharge manifold near the fire pump.
(h) When a fire monitor is connected to the fire main system, it must lead from a discharge manifold near the fire pump.
(i) The total cross-sectional area of piping leading from a fire pump may not be less than that of the pump-discharge outlet.
(j) In no case may a pump connected to a line for flammable or combustible liquid be used as a fire pump.
(k) A fire pump must be capable of both manual operation at the pump and, if a remote operating station is fitted, operation at that station.