9 Ships Operational Procedures
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Statutory Documents - IMO Publications and Documents - Resolutions - Assembly - IMO Resolution A.868(20) – Guidelines for the Control and Management of Ships Ballast Water to Minimize the Transfer of Harmful Aquatic Organisms and Pathogens – (Adopted on 27 November 1997) - Annex - Guidelines for the Control and Management of Ships Ballast Water to Minimize the Transfer of Harmful Aquatic Organisms and Pathogens - 9 Ships Operational Procedures

9 Ships Operational Procedures

  9.1 Precautionary practices

  9.11 Minimizing uptake of harmful aquatic organisms, pathogens and sediments

 When loading ballast, every effort should be made to avoid the uptake of potentially harmful aquatic organisms, pathogens and sediment that may contain such organisms. The uptake of ballast water should be minimized or, where practicable, avoided in areas and situations such as:

  • areas identified by the port State in connection with advice relating to 8.2.2 above;
  • in darkness when bottom dwelling organisms may rise up in the water column;
  • in very shallow water; or
  • where propellers may stir up sediment.

  9.1.2 Removing Ballast Sediment on a Timely Basis

 Where practicable, routine cleaning of the ballast tank to remove sediments should be carried out in mid-ocean or under controlled arrangements in port or dry dock, in accordance with the provisions of the ship's ballast water management plan.

  9.1.3 Avoiding Unnecessary Discharge of Ballast Water

 If it is necessary to take on and discharge ballast water in the same port to facilitate safe cargo operations, care should be taken to avoid unnecessary discharge of ballast water that has been taken up in another port.

  9.2 Ballast water management options

  9.2.1 Ballast water exchange

 Near-coastal (including port and estuarine) organisms released in mid-ocean and oceanic organisms released in coastal waters do not generally survive.

When exchanging ballast at sea, guidance on safety aspects of ballast water exchange as set out in appendix 2 should be taken into account. Furthermore, the following practices are recommended:

  • where practicable, ships should conduct ballast exchange in deep water, in open ocean and as far as possible from shore. Where this is not possible, requirements developed within regional agreements may be in operation, particularly in areas within 200 nautical miles from shore. Consistent with 9.1.2 above, all of the ballast water should be discharged until suction is lost, and stripping pumps or eductors should be used if possible;
  • where the flow-through method is employed in open ocean by pumping ballast water into the tank or hold and allowing the water to overflow, at least three times the tank volume should be pumped through the tank;
  • where neither form of open ocean exchange is practicable, ballast exchange may be accepted by the port State in designated areas; and
  • other ballast exchange options approved by the port State.

  9.2.2 Non-release or minimal release of ballast water

 In cases where ballast exchange or other treatment options are not possible, ballast water may be retained in tanks or holds. Should this not be possible, the ship should only discharge the minimum essential amount of ballast water in accordance with port States' contingency strategies.

  9.2.3 Discharge to reception facilities

 If reception facilities for ballast water and/or sediments are provided by a port State, they should, where appropriate, be utilized.

  9.2.4 Emergent and new technologies and treatments

  9.2.4.1 If suitable new and emergent treatments and technologies prove viable, these may substitute for, or be used in conjunction with, current options. Such treatments could include thermal methods, filtration, disinfection including ultraviolet light, and other such means acceptable to the port State.

  9.2.4.2 Results concerning the application and effectiveness of new ballast water management technologies and associated control equipment should be notified to the Organization with a view to evaluation and incorporation, as appropriate, into these Guidelines.


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