5.2 Identification of critical systems
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1369 – Interim Explanatory Notes for the Assessment of Passenger Ship Systems' Capabilities After a Fire or Flooding Casualty– (22 June 2010)1 - Annex – Interim Explanatory Notes for the Assessment of Passenger Ship Systems Capabilities After A Fire or Flooding Casualty - 5 Overall Assessment of Essential Systems - 5.2 Identification of critical systems

5.2 Identification of critical systems

  5.2.1 Essential systems identified to be fully redundant for all fire and flooding casualty cases not exceeding the threshold (e.g., when runs of cables, pipes and equipment are duplicated and adequately separated), need not be further analysed as described in section 6.

  5.2.2 For the arrangement of equipment, components or connections reference may be made to relevant interpretations contained in paragraph 2 of appendix 1 to these Interim Explanatory Notes. Where other solutions are adopted, equipment, components or connections should be further analysed as described in section 6.

  5.2.3 Manual action by the crew, to provide ship systems' capabilities, may also be possible but should be assessed in detail taking into account that:

  • .1 manual action should only be acceptable by the Administration in connection with an agreed defined number of fire and flooding casualties and should be clearly described in the documentation that should be prepared as per section 7;

  • .2 compliance with the return to port criteria should be based on the assumption that any manual action that may be required for the ship to return to port, or for any essential system to remain operational, following a casualty:

    • .1 is pre-planned, pre-set and instructions as well as necessary materials are available on board;

    • .2 is performed on systems designed to ensure that the required manual action can be completed within one hour from the time the action started; and

    • .3 emergency lighting and a means of communication is demonstrated available in the area where manual actions are to be taken; and

  • .3 in general, feasibility of manual actions should be demonstrated by tests or drills, as applicable.

  5.2.4 Performance requirements applicable to any essential system may be analysed and documented separately; however, any relevant information should be included in the overall assessment of essential systems' report.


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