Part B - Requirements for Passenger Craft
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Statutory Documents - IMO Publications and Documents - International Codes - HSC Code - International Code of Safety for High Speed Craft, 1994 – Resolution MSC.36(63) - Annex - International Code of Safety for High Speed Craft, 1994 - Chapter 12 - Electrical Installations - Part B - Requirements for Passenger Craft

Part B - Requirements for Passenger Craft

12.7 General

  12.7.1 Separation and duplication of electrical supply should be provided for duplicated consumers of essential services. During normal operation the systems may be connected to the same power-bus, but facilities for easy separation should be provided. Each system should be able to supply all equipment necessary to maintain the control of propulsion, steering, stabilization, navigation, lighting and ventilation, and allow starting of the largest essential electric motor at any load. Automatic load-dependent disconnection of non-essential consumers may be allowed.

  12.7.2 Emergency source of electrical power

Where the main source of electrical power is located in two or more compartments which are not contiguous, each of which has its own self-contained systems, including power distribution and control systems, completely independent of each other and such that a fire or other casualty in any one of the spaces will not affect the power distribution from the others, or to the services required by 12.7.3 or 12.7.4, the requirements of 12.3.1, 12.3.2 and 12.3.4 may be considered satisfied without an additional emergency source of electrical power, provided that:

  • .1 there is at least one generating set, meeting the requirements of 12.3.12 and of sufficient capacity to meet the requirements of 12.7.3 or 12.7.4 in each of at least two non-contiguous spaces;

  • .2 the arrangements required by .1 in each such space are equivalent to those required by 12.3.6.1, 12.3.7 to 12.7.3 12.3.11 and 12.4 so that a source of electrical power is available at all times to the services required by or 12.7.4: and

  • .3 the generator sets referred to in .1 and their self-contained systems are installed such that one of them remains operable after damage or flooding in any one compartment.

  12.7.3 For category A craft, the emergency source of power should be capable of supplying simultaneously the following services:

  • .1 for a period of 5 h emergency lighting:

    • .1.1 at the stowage positions of life-saving appliances;

    • .1.2 at all escape routes such as alleyways, stairways, exits from accommodation and service spaces, embarkation points, etc;

    • .1.3 in the public spaces;

    • .1.4 in the machinery spaces and main emergency generating spaces including their control positions;

    • .1.5 in control stations;

    • .1.6 at the stowage positions for firemen's outfits; and

    • .1.7 at the steering gear:

  • .2 for a period of 5 h:

    • .2.1 main navigation lights, except for "not under command" lights:

    • .2.2 electrical internal communication equipment for announcements for passengers and crew required during evacuation;

    • .2.3 fire detection and general alarm system and manual fire alarms; and

    • .2.4 remote control devices of fire-extinguishing systems, if electrical;

  • .3 for a period of 4 h of intermittent operation:

    • .3.1 the daylight signalling lamps, if they have no independent supply from their own accumulator battery; and

    • .3.2 the craft's whistle, if electrically driven;

  • .4 for a period of 5 h:

    • .4.1 craft radio facilities and other loads as set out in 14.12.2; and

    • .4.2 essential electrically powered instruments and controls for propulsion machinery, if alternate sources of power are not available for such devices;

  • .5 for a period of 12 h, the "not under command" lights; and

  • .6 for a period of 10 min:

    • .6.1 power drives for directional control devices including those required to direct thrust forward and astern, unless there is a manual alternative acceptable to the Administration as complying with 5.2.3.

  12.7.4 For category B craft, the electrical power available should be sufficient to supply all those services that are essential for safety in an emergency, due regard being paid to such services as may have to be operated simultaneously. The emergency source of electrical power should be capable, having regard to starting currents and the transitory nature of certain loads, of supplying simultaneously at least the following services for the periods specified hereinafter, if they depend upon an electrical source for their operation.

  • .1 for a period of 12 h, emergency lighting:

    • .1.1 at the stowage positions of life-saving appliances;

    • .1.2 at all escape routes, such as alley ways, stairways, exits from accommodation and service spaces, embarkation points, etc;

    • .1.3 in the passenger compartments;

    • .1.4 in the machinery spaces and main emergency generating spaces including their control positions;

    • .1.5 in control stations:

    • .1.6 at the stowage positions for firemen's outfits; and

    • .1.7 at the steering gear.

  • .2 for a period of 12 h:

    • .2.1 the navigation lights and other lights required by the International Regulations for Preventing Collisions at Sea in force;

    • .2.2 electrical internal communication equipment for announcements for passengers and crew required during evacuation;

    • .2.3 fire detection and general alarm system and manual fire alarms; and

    • .2.4 remote control devices of fire-extinguishing systems, if electrical;

  • .3 for a period of 4 h on intermittent operation:

    • .3.1 the daylight signalling lamps, if they have no independent supply from their own accumulator battery; and

    • .3.2 the craft's whistle, if electrically driven;

  • .4 .4 for a period of 12 h:

    • .4.1 the navigational equipment as required by chapter 13. Where such provision is unreasonable or impracticable, the Administration may waive this requirement for craft of less than 5,000 tons gross tonnage;

    • .4.2 essential electrically powered instruments and controls for propulsion machinery, if alternate sources of power not available for such devices;

    • .4.3 one of the fire pumps required by 7.7.8.1;

    • .4.4 the sprinkler pump and drencher pump, if fitted;

    • .4.5 the emergency bilge pump and all the equipment essential for the operation of electrically powered remote controlled bilge valves as required by chapter 10, and

    • .4.6 craft radio facilities and other loads as set out in 14.12.2;

  • .5 for a period of 30 min, any watertight doors, required by chapter 2 to be power operated, together with their indicators and warning signals;

  • .6 for a period of 10 min, power drives for directional control devices including those required to direct thrust forward and astern, unless there is a manual alternative acceptable to the Administration as complying with 5.2.3.

  12.7.5 Transitional source of emergency electrical power

The transitional source of emergency electrical power required by paragraph 12.3.6.1.3 may consist of an accumulator battery suitably located for use in an emergency which should operate without recharging while maintaining the voltage of the battery throughout the discharge period within 12% above or below its nominal voltage and be of sufficient capacity and so arranged as to supply automatically in the event of failure of either the main or emergency source of electrical power at least the following services, if they depend upon an electrical source for their operation:

  • .1 for a period of 30 min, the load specified in 12.7.3.1, .2 and .3, or in 12.7.4.1, .2 and .3; and

  • .2 with respect to the watertight doors:

    • .2.1 power to operate the watertight doors, but not necessarily simultaneously, unless an independent temporary source of stored energy is provided. The power source should have sufficient capacity to operate each door at least three times, i.e. closed - open - closed, against an adverse list of 15°; and

    • .2.2 power to the control, indication and alarm circuits for the watertight doors for half an hour.

  12.7.6 The requirements of 12.7.5 may be considered satisfied without the installation of a transitional source of emergency electrical power if each of the services required by that paragraph has independent supplies, for the period specified, from accumulator batteries suitably located for use in an emergency. The supply of emergency power to the instruments and controls of the propulsion and direction systems should be uninterruptible.

  12.7.7 In category A craft having limited public spaces, emergency lighting fittings of the type described in 12.7.9.1 as meeting the requirements of 12.7.3.1 and 12.7.5.1 may be accepted, provided that an adequate standard of safety is attained.

  12.7.8 Provision should be made for the periodic testing of the complete emergency system including the emergency consumers required by 12.7.3 or 12.7.4 and 12.7.5, and should include the testing of automatic starting arrangements.

  12.7.9 In addition to the emergency lighting required by 12.7.3.1, 12.7.4.1 and 12.7.5.1 on every craft with special category spaces:

  • .1 all passenger public spaces and alleyways should be provided with supplementary electric lighting that can operate for at least 3 h when all other sources of electric power have failed and under any condition of heel. The illumination provided should be such that the approach to the means of escape can be readily seen. The source of power for the supplementary lighting should consist of accumulator batteries located within the lighting units that are continuously charged, where practicable, from the emergency switchboard. Alternatively, any other means of lighting, which is at least as effective, may be accepted by the Administration.

    The supplementary lighting should be such that any failure of the lamp will be immediately apparent. Any accumulator battery provided should be replaced at intervals having regard to the specified service life in the ambient condition that it is subject to in service; and

  • .2 a portable rechargeable battery operated lamp should be provided in every crew space alleyway, recreational space and every working space which is normally occupied unless supplementary emergency lighting, as required by .1, is provided.

  12.7.10 Distribution systems should be so arranged that fire in any main vertical zone will not interfere with services essential for safety in any other such zone. This requirement will be met if main and emergency feeders passing through any such zone are separated both vertically and horizontally as widely as is practicable.


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