Section 3 Fire detection and fire-extinguishing systems and equipment

3.1.1 All fire-extinguishers are to be approved types. If considered necessary, the Committee may require the makers to produce evidence from a recognized independent testing authority regarding the suitability of their appliances.

3.1.2 The extinguishers required for use in the machinery spaces of floating docks burning oil as fuel are to be of a type discharging froth, carbon dioxide gas, dry powder, or other approved medium suitable for extinguishing oil fires. Fire-extinguishers containing an extinguishing medium which either itself or when in use gives off gases harmful to persons are not to be used. For radio rooms and switchboards, extinguishers containing not more than 1,136 litres of carbon tetrachloride or similar media may be permitted subject to such extinguishers being additional to any required by Pt 2, Ch 3, 4 Fire pumps and water service pipes.

3.1.3 The capacity of required portable fluid extinguishers is not to be more than 13,5 litres and not less than 9 litres. Other extinguishers are not to be in excess of the equivalent portability of the 13,5 litre fluid extinguisher and are not to be less than the fire-extinguishing equivalent of a 9 litre fluid extinguisher.

3.1.4 A spare charge is to be provided for each required fire-extinguisher which can be readily re-charged on board. If this cannot be done, duplicate extinguishers are to be provided.

3.1.5 One of the portable fire-extinguishers intended for use in any space is to be stowed near the entrance to that space.

3.2.1 

3.3.1 Where provision is made for the injection of gas into machinery spaces for fire-extinguishing purposes, the necessary pipes for conveying the gas are to be provided with control valves or cocks which are to be so placed that they will be easily accessible and not readily cut-off from use by an outbreak of fire. These control valves or cocks are to be so marked as to indicate clearly the compartments to which the pipes are led. Suitable provision is to be made to prevent inadvertent admission of the gas to any compartment.

3.3.2 The piping is to be of adequate size and so arranged as to provide effective distribution of fire-smothering gas. Steel distribution pipes are to be galvanized internally and externally, and are not to be smaller than 20 mm bore for carbon dioxide.

3.4.1 Where carbon dioxide is used as an extinguishing medium for spaces containing boilers, engines or gas turbines, the quantity of gas carried is to be sufficient to give a minimum volume of free gas equal to the larger of the following:

1. 40 per cent of the gross volume of the largest space, the volume to include the casing up to the level at which the horizontal area of the casing is 40 per cent or less of that of the space concerned; or

2. 35 per cent of the entire volume of the largest space including the casing.

When evaluating the quantity of carbon dioxide gas required for the machinery spaces, the free air content of the starting air receivers is to be added to the above gross space volumes. The volume of gas is to be calculated at 0,56 m³/kg.

3.4.2 Where carbon dioxide is used as the extinguishing medium for spaces containing boilers, engines or gas turbines, the fixed piping system is to be such that 85 per cent of the gas can be discharged into the space within two minutes.

3.4.3 The gas cylinders and main controls are to be located to the Surveyor’s satisfaction in a cool and well ventilated position, not likely to be made inaccessible by fire. Provision is to be made for changing the cylinders and checking their contents by weighing or other approved means. Operating instructions are to be displayed at the controls.

3.5.1 Means are to be provided whereby audible warning is given automatically before fire-smothering gas can be released into the machinery space and any other working space.

3.6.1 Any required fixed froth fire-extinguishing system is to be able to discharge a quantity of froth sufficient to cover to a depth of 150 mm the largest area over which fuel oil is liable to spread.

3.6.2 Such a system is to be controlled from an easily accessible position or positions, outside the space to be protected, which will not be readily cut-off by an outbreak of fire. The distribution pipes are to be of steel, galvanized internally and externally.

3.7.1 All required fire detection systems are to be capable of automatically indicating the presence or inception of fire and its location. Indicators are to be centralized in control stations. The indicators may be distributed among several stations subject to approval by the Surveyor.

3.7.2 Electrical equipment used in the operation of required fire detection systems is to have two separate sources of power, one of which should be an emergency source.

3.7.3 The alarm system is to operate both audible and visible signals at the main stations referred to in Pt 2, Ch 3, 3.7 Fire detection systems 3.7.1. Where it is intended that the engine and/or boiler rooms will not be continuously manned, the alarm system is to operate both audible and visible signals at the station from which the machinery is controlled.

3.8.1 Fixed pressurized water-spraying systems for boiler rooms with oil fired boilers and engine rooms with oil engines or gas turbines are to be provided with spraying nozzles of an approved type.

3.8.2 The number and arrangement of the nozzles is to be to the satisfaction of the Surveyor, and such as to ensure an effective distribution of water in the spaces to be protected. Nozzles are to be fitted above bilges, tank tops and other areas over which fuel oil is liable to spread and also above fuel oil settling and service tanks, heaters, pumping units, purifiers and other main fire hazards in the boiler and engine rooms.

3.8.3 The system may be divided into sections, the distribution manifolds of which are to be operated from easily accessible positions outside the spaces to be protected and which will not be readily cut-off by an outbreak of fire.

3.8.4 The system is to be kept charged at the necessary pressure and the pump supplying the water for the system is to be put automatically into action by a pressure drop in the system.

3.8.5 The pump is to be capable of simultaneously supplying at the necessary pressure all sections of the system in any one compartment to be protected. The pump and its controls are to be installed outside the space or spaces to be protected. It must not be possible for a fire in the space or spaces protected by the water-spraying system to put the system out of action.

3.8.6 Special precautions are to be taken to prevent the nozzles from becoming clogged by impurities in the water or corrosion of piping, nozzles, valves and pump.

3.9.1 Provision is to be made for closing all openings which might admit air to machinery spaces and to other spaces where there is risk of an oil fire. Skylights and ventilators of machinery spaces are to be capable of being shut from the deck or from a safe position outside these spaces. Provision is to be made for rapidly stopping all fans from positions outside such spaces.

3.10.1 Gutterways are to be arranged at the foot of bulkheads in boiler rooms to ensure that leakage shall have free drainage to the wells or limbers.

3.10.2 Drip trays or gutterways with suitable draining arrangements are to be provided for all tanks which do not form part of the hull structure, at pumps, valves and elsewhere where there is a possibility of leakage. Drip trays are also to be fitted under oiltight decks, except if these are completely welded, when drip trays need only be fitted over the boilers.

3.10.3 If stores are carried in a compartment adjacent to a fuel oil settling tank which may be heated, the compartment side of the bulkhead or deck is to be insulated or equivalent arrangements provided.

3.10.4 In machinery spaces, two means of escape are to be provided from each engine room and boiler room. These are to be as widely separated as practicable.