2 Damage and flooding extent for the floatability assessment
Clasification Society 2024 - Version 9.40
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 - Appendix 1 – Procedure for The Determination of the Impact of Open Watertight Doors on Passenger Ships Survivability (Floatability Assessment) - 2 Damage and flooding extent for the floatability assessment

2 Damage and flooding extent for the floatability assessment

  2.1 In every case in which a determination that keeping one or more watertight doors open during navigation is absolutely necessary, floatability assessment calculations should be performed.

  2.2 The extent of damage to be assumed for the floatability assessment should be as defined in SOLAS regulation II-1/8.3. In addition, watertight compartments inboard of the transverse extent of damage should be assumed flooded, irrespective of whether any longitudinal bulkheads are fitted with watertight doors, if:

  • .1 the inboard compartment is within the longitudinal damage extent; and

  • .2 the inboard compartment is connected by the watertight door(s) under investigation which are proposed to remain open during navigation.

 If any lesser damage extents than indicated above would result in a more severe condition with respect to the floatability criteria, then such damage extents should be assumed in the calculations. In this context, the damage extent should be assumed as both penetrating and not penetrating the double bottom.

  2.3 The floatability assessment should account for the worst cases involving the additional flooding of compartments connected with watertight doors requested to remain open during navigation. The extent of flooding assumed for the floatability assessment calculations should be as follows: any watertight door that is requested to remain open during navigation may be considered closed in each case of flooding if it is in a watertight bulkhead that is located away from the damage extent by at least one undamaged transverse watertight bulkhead/door.

Parent topic: Appendix 1 – Procedure for The Determination of the Impact of Open Watertight Doors on Passenger Ships Survivability (Floatability Assessment)
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