7 Permission for category A watertight doors to remain open
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1380 – Guidance for Watertight Doors on Passenger Ships Which May be Opened During Navigation – (10 December 2010) - Annex – Guidance for Watertight Doors on Passenger Ships Which may be Opened During Navigation - 7 Permission for category A watertight doors to remain open

7 Permission for category A watertight doors to remain open

  7.1 When applying to the Administration for permission for a watertight door to be qualified as a category A watertight door, the Company, as defined in SOLAS regulation IX/1.2, should conduct a risk assessment and consider the ship's survivability as a primary issue. The scope of the risk assessment should be balanced against operational needs.

  7.2 The Administration, when permitting watertight doors to remain open, should take into account the outcome of the risk assessment conducted by the Company, which includes the procedure for the determination of the impact of open watertight doors on passenger ship survivability, set out in appendix 1 (hereinafter "floatability assessment").

  7.3 The Administration may continue to permit those watertight doors (refer to paragraph 6.1), which have been permitted to remain open during navigation prior to this Guidance becoming effective, to remain open during navigation. However, this does not restrict an Administration from reconsidering whether any category A watertight doors should remain open when operating under the conditions described in paragraph 9.

  7.4 The necessity for a watertight door to remain open during navigation should be demonstrated by the Company. The Company should satisfy the Administration with relevant information, such as operational needs, number of passages through the watertight door per time unit, alternative passageways around the watertight door and results from the risk assessment. The Company should also submit a copy of the relevant sections of their safety management procedures relating to the operation of watertight doors during navigation, as well as related information such as restrictions or limitations on when watertight doors may remain open.

  7.5 Before permitting a watertight door to remain open during navigation, the Administration should evaluate the information described in 7.1 and 7.4 and verify that:

  • .1 the watertight door meets the technical requirements of SOLAS regulations II-1/13.5.1 to 13.5.3 and 13.6 (previous SOLAS regulations II-1/15.6.1 to 15.6.4), which also includes the requirements in paragraph 7 of SOLAS regulation II-1/13 (previous SOLAS regulation II-1/15);

  • .2 the floatability assessment (appendix 1) has been taken into account; and

  • .3 the proposed category A watertight door meets the criteria specified in SOLAS regulation II-1/22.4 (previous SOLAS regulation II-1/15.9.3).

  7.6 The flowchart in appendix 3 and the checklist for the technical standards of the watertight doors in appendix 2 may be used as guidance in the evaluation.

  7.7 It is also important for an Administration to envisage the conditions under which adjacent watertight doors of category B or C may be opened during navigation for certain limited periods of time as permitted by SOLAS regulation II-1/22.3 (previous SOLAS regulation II-1/15.9.2), with a view towards preserving watertight subdivision and enhancing survivability. Additional factors, such as the area in which the ship is operating, should also be assessed to consider any additional risks or potentially hazardous situations (see list in paragraph 9 for consideration of such risks).

  7.8 All category A doors shall be clearly indicated in the ship's stability information and shall always be ready to be immediately closed. Instructions regarding these watertight doors should be incorporated in the ship's safety management system and included in the ship's operational limitations in accordance with SOLAS chapter V requirements.

  7.9 A watertight door should not be permitted to remain open during navigation in potentially hazardous situations, if the ship does not meet the floatability criteria given in section 3 in appendix 1 for each associated extent of flooding.

  7.10 A watertight door may be permitted to remain open when operating under normal situations as defined in paragraph 10.3, if the ship does not meet the floatability criteria when the overall risk assessment indicated a level of safety acceptable to the Administration.


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