FIRE MAIN

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Pipes are normally galvanised steel. A deck main screw-lift, isolating valve is to be fitted, accessible from outside the machinery space, in case of damaged pipes in the engine room. The deck main must be drained at the lowest point to prevent damage or becoming unusable due to freezing. There must be at least 2, independently powered, pumps to supply water to the firemain, with remote start facility. Each of these pumps should be capable of supplying two jets of water, 12 m long x 12mm diameter to any part of the ship, one from a single length of hose. [Lloyds].

Solas [II-2, 4.2] gives a pressure that must be maintained at the hydrants;

                                    Passenger ship             4.0 bar

                                    Cargo ship                   2.7 bar

Any part of the vessel must be able to be reached by two jets, one from a single length of hose.

Passenger vessels above 4000T must have three fire pumps, and automatic starting should a hydrant be opened.

Tankers require isolating valves on deck at least every 40m.

Sanitary, ballast, bilge or general service pumps may be accepted as fire pumps provided they are not usually used for pumping oil.

The Emergency Fire Pump

One of the dedicated pumps will be the emergency pump, and all parts of the unit such as sea suctions, power supplies and pipes must be separate from the compartment containing the main fire pump. The location must be accessible from the open deck and be in a well ventilated space.

The pump must be able to operate at the lightest draught that will be encountered in service, and a means of air extraction for priming purposes must be provided if the pump is more than two metres above the lightest draught (if the pump is not self‑priming).

Where an IC engine is used as the prime mover for the pump, hand starting is preferred, but if impracticable the alternative arrangement must provide for 12 starts in a thirty-minute period. The immediate use fuel supply should be sufficient for three hours with a reserve for 15 hours. The fuel used must be suitable for low temperature operation (M 1165),

The pump system must be tested weekly and a record made of the test. Deck personnel are to be familiar with both the starting and the operation of the pump.

The International Connection

A standard sized flange, which allows connection to the ship's firemain from external sources. The flange, bolts and joints must be kept ready for use and easily identifiable.

Must include suitable bolts, washers and gasket.

4x16mm Bolts 50mm long.

Gasket for 10 bar operating pressure.

The connection must be readily attachable on each side of the vessel.