Section 4 Fire protection

4.1.1 In ships which are not provided with a water spray system as described in Pt 7, Ch 3, 4.2 Water spray systems all windows and port lights are to be provided with efficient deadlights or external steel shutters, except in the wheelhouse.

4.2.1 Ships which are intended to operate in close proximity to a large fire will require protection from the heat radiated from the fire. Such protection may be afforded by a system which provides a water spray over the surface of the ship, or by a combination of insulation and a water spray system. Alternative arrangements providing an equivalent level of protection may be accepted where it can be demonstrated that such arrangements are effective for the environmental conditions in which the ship is intended to operate.

4.2.2 The water spray system is to be a fixed system which is capable of delivering a spray of water over all the exposed external vertical surfaces of the hull in the lightest sea-going condition, including the superstructures and deckhouses and over the monitor position. The water spray system will also be required to cover the areas of deck which form the crowns of machinery spaces and other spaces containing combustible materials.

4.2.3 The system is to have a capacity of 10 litres/min per m² of the protected area of uninsulated steel and 5 litres/min per m² of the protected area which is insulated internally to A-60 standard.

4.2.4 The system may be divided into sections, so that it will be possible to enable the closing down of those sections covering surfaces which are not exposed to radiant heat.

4.2.5 The nozzles are to be arranged to give an even distribution of water spray over the protected area.

4.2.6 The pumping capacity is to be sufficient to supply simultaneously at the required pressure the sections which serve the maximum area which may be exposed to radiant heat from a fire. If the main fire pumps are used for this purpose, they are to be capable of operating this system and the monitors and hose stations simultaneously at the required pressures, see also Pt 7, Ch 3, 3.2 Pumps 3.2.2.

4.2.7 Deck scuppers and freeing ports are to be of sufficient area to ensure efficient drainage of water from decks and horizontal surfaces in all conditions when the water spray system is in operation.