Internal openings
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - International Codes - 1989 MODU Code – Code for the Construction and Equipment of Mobile Offshore Drilling Units, 1989 – Resolution A.649(16) - Chapter 3 – Subdivision, Stability and Freeboard - 3.6 Watertight integrity - Internal openings

Internal openings

  3.6.4 The means to ensure the watertight integrity of internal openings should comply with the following:

  • .1 Doors and hatch covers which are used during the operation of the unit while afloat should be remotely controlled from the central ballast control station and should also be operable locally from each side. Open/shut indicators should be provided at the control station .

  • .2 Doors or hatch covers which are normally closed while the unit is afloat should be provided with an alarm system (e.g. light signals) showing personnel both locally and at the central ballast control station whether the doors or hatch covers in question are open or closed. A notice should be affixed to each such door or hatch cover stating that it is not to be left open while the unit is afloat.

  3.6.5 The means to ensure the watertight integrity of internal openings which are kept permanently closed during the operation of the unit, while afloat, should comply with the following:

  • .1 A notice should be affixed to each such closing appliance stating that it is to be kept closed while the unit is afloat; however, manholes fitted with close bolted covers need not be so marked .

  • .2 On self-elevating units, an entry should be made in the official log-book or tour report, as applicable, stating that all such openings have been witnessed closed before the unit becomes waterborne.


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