Regulation 21 - Casualty threshold, safe return to port and safe areas
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Regulation 21 - Casualty threshold, safe return to port and safe areas

1 Application

 Passenger ships constructed on or after 1 July 2010 having length, as defined in regulation II-1/2.5, of 120 m or more or having three or more main vertical zones shall comply with the provisions of this regulation.

2 Purpose

 The purpose of this regulation is to establish design criteria for a ship's safe return to port under its own propulsion after a casualty that does not exceed the casualty threshold stipulated in paragraph 3 and also provides functional requirements and performance standards for safe areas.

3 Casualty threshold

 The casualty threshold, in the context of a fire, includes:

  • .1 loss of space of origin up to the nearest "A" class boundaries, which may be a part of the space of origin, if the space of origin is protected by a fixed fire extinguishing system; or

  • .2 loss of the space of origin and adjacent spaces up to the nearest "A" class boundaries, which are not part of the space of origin.

4 Safe return to port footnote

 When fire damage does not exceed the casualty threshold indicated in paragraph 3, the ship shall be capable of returning to port while providing a safe area as defined in regulation 3. To be deemed capable of returning to port, the following systems shall remain operational in the remaining part of the ship not affected by fire:

  • .1 propulsion;

  • .2 steering systems and steering-control systems;

  • .3 navigational systems;

  • .4 systems for fill, transfer and service of fuel oil;

  • .5 internal communication between the bridge, engineering spaces, safety centre, fire-fighting and damage control teams, and as required for passenger and crew notification and mustering;

  • .6 external communication;

  • .7 fire main system;

  • .8 fixed fire-extinguishing systems;

  • .9 fire and smoke detection system;

  • .10 bilge and ballast system;

  • .11 power-operated watertight and semi-watertight doors;

  • .12 systems intended to support "safe areas" as indicated in paragraph 5.1.2;

  • .13 flooding detection systems; and

  • .14 other systems determined by the Administration to be vital to damage control efforts.

5 Safe area(s)

5.1 Functional requirements:

  .1 the safe area(s) shall generally be internal space(s); however, the use of an external space as a safe area may be allowed by the Administration taking into account any restriction due to the area of operation and relevant expected environmental conditions;

  .2 the safe area(s) shall provide all occupants with the following basic servicesfootnote to ensure that the health of passengers and crew is maintained:

  • .1 sanitation;

  • .2 water;

  • .3 food;

  • .4 alternate space for medical care;

  • .5 shelter from the weather;

  • .6 means of preventing heat stress and hypothermia;

  • .7 light; and

  • .8 ventilation;

  .3 ventilation design shall reduce the risk that smoke and hot gases could affect the use of the safe area(s); and

  .4 means of access to life-saving appliances shall be provided from each area identified or used as a safe area, taking into account that a main vertical zone may not be available for internal transit.

5.2 Alternate space for medical care

 Alternate space for medical care shall conform to a standard acceptable to the Administration.footnote


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