5 Operational Procedures
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Specifications and Manuals - Dedicated Clean Ballast Tanks - Annex 1 - Revised Specifications for Oil Tankers with Dedicated Clean Ballast Tanks - 5 Operational Procedures

5 Operational Procedures

  5.1 The pumps and piping system conveying CBT ballast shall be flushed with water before clean ballast is loaded, discharged or transferred.

  5.2 The water for flushing shall be pumped from a sea chest or dedicated clean ballast tank through the pump and piping system of the dedicated clean ballast tank and then to a slop tank.

  5.3 If sections of the piping system for CBT ballast are so arranged that they must be flushed with water from the dedicated clean ballast tanks then the minimum quantity of flushing water to be provided in such tanks at all times shall be the greater of either 10 times the volume of the piping to be flushed or sufficient to provide that level in the tank which would allow the piping to run full of water during the flushing before vortexing starts to admit air into the piping. Alternative methods for the retention of clean ballast required by this paragraph shall be to the satisfaction of the Administration.

  5.4 After the loading, discharging or transferring of clean ballast the valves specified in paragraph 4.2.2 shall be shut and the piping system drained.

  5.5 The overboard discharge of all CBT ballast shall be monitored by an oil content meter.

  5.6 The simultaneous discharge of clean ballast while loading cargo or the simultaneous loading of clean ballast while discharging cargo shall not be undertaken except where there is an effective two-valve separation between the ballast and the cargo systems or when cargo tanks are served by individual pumps.

  5.7 Ballast water must not be allowed to free fall into ballast tanks into which hydrocarbon gases have leaked. The Dedicated Clean Ballast Tank Operation Manual shall provide either for such tanks to be gas freed before ballasting or for alternative tanks to be used to obviate the danger posed by splashing and free fall of water in tanks containing hydrocarbon gases within the explosive range.


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