|SOLAS-74 Fire Protection Requirements|
Fire Protection, Fire Detection and Fire Extinction (SOLAS-74)
The regulations are provided in Chapter II-2 of SOLAS 74 and compliance will satisfy the regulatory strategy as per section 3(9), (10), (11), (12), (13) and (14). The regulations recognize that absolute fire prevention is not possible.
However they seek to protect lesser fire hazardous spaces from higher fire hazardous spaces by the provision of fire protection divisions. In this way, for example, accommodation is protected from the high fire hazardous engine room and in the event of flammable cargoes being carried, the cargo area. In addition to the provision of fire protection divisions in this respect the regulations also require that the flammable atmosphere in the cargo tanks of oil tankers over a certain size, be inerted. Exhaust gas from the ships essential engineering system is utilized for this purpose.
Fire protection divisions are also required such as to contain any outbreak of fire within a sufficiently small space, such that given early detection, it can be successfully extinguished.
To further facilitate this basic philosophy, the regulations also require the provision of fire detection systems and means of fire extinction.
The primary fire extinction system is the fire main, which is required to extend throughout the ship, thus making use of a shipâ€™s only fire fighting advantage, that of an inexhaustible supply of water. Hydrants are required together with hoses, such that two jets of water may be directed into any normally accessible part of the ship. Pumps to drive the fire main will usually be provided in the engine room. Thus, to provide for a situation in which a fire may occur in the engine room, rendering these pumps inoperable, an emergency fire pump is required, situated in a separate location.
A valve is to be provided in the fire main, outside the engine room, so that the fire main system inside the engine room, which may also be rendered ineffective in the event of an engine room fire, may be isolated from the remainder of the system. Thus, the emergency fire pump must be able to supply the fire main system independently of the main fire pumps and fire main piping situated in the engine room.
Additional to the requirement for a fire main, the regulations also provide for portable fire extinguishers and fixed extinguishing systems in engine rooms, cargo pump rooms, accommodation and in cargo spaces or cargo areas.
The extinguishing medium in fixed systems in engine and cargo pump rooms may be gas, high expansion foam or water (pressure water spray). Low expansion foam systems may be provided in addition to any of these. In dry cargo spaces, intended for flammable cargoes, fixed gas systems are specified. It should be noted that in respect of gas systems, with a view to reducing air pollution, new installations of halogenated gas systems are prohibited.
In cargo areas of oil tankers (carrying oil with a low flash point), fixed low expansion foam systems are required. This is also a requirement of the Bulk Chemical and International Bulk Chemical Codes for chemical tankers, but if chemical cargoes are carried which are miscible with water, such as alcohols, then the foam media provided should be alcohol resistant. Also, in such cases, dry chemical powder systems may be provided as an alternative. Water spray is also permitted as an alternative for certain cargoes.
For liquefied gas carriers, the Gas Carrier and International Gas Carrier Codes require that a water spray system be provided in the cargo area, for cooling, fire prevention and crew protection. Dry chemical powder systems are required for fire extinguishing purposes.
Fixed fire extinguishing systems in crew and passenger accommodation are of the automatic water sprinkler type, installed in association with fire detection and fire alarm systems.
Finally, with respect to the fire protection detection and extinction requirements of SOLAS Chapter II-2, it is of interest to note the following basic principles stated therein as underlying the regulations in that chapter, having regard to the type of ships and the potential fire hazard involved:
- division of ship into main vertical zones by thermal and structural boundaries;
- separation of accommodation spaces from the remainder of the ship by thermal and structural boundaries;
- restricted use of combustible materials;
- detection of any fire in the zone of origin;
- containment and extinction of any fire in the space of origin;
- protection of means of escape or access for fire fighting
- ready availability of fire-extinguishing appliances;
- minimization of possibility of ignition of flammable cargo vapor.
It should also be noted that the problem of engine room fires caused by oil fuel leakage onto hot surfaces is addressed as SOLAS amendment, reg. 15- 2.9 to 2.12, Chapter II-1. The amendment will be applicable to ships the keels of which are laid or at a similar stage of construction on or after 1 July 1998, and all ship types to which the Convention applies, and requires that fuel delivery lines and adjacent hot surfaces are to be jacketed and protected to contain leakages and prevent oil spraying onto hot surfaces or other sources of ignition. Existing ships built before 1 July 1998 are to comply with the regulations not later than 1 July 2003, with some alternative arrangements for engines of 375kW and below.