In respect of a chemical tanker, carrying category “X”, “Y” & “Z” Noxious Liquid Substances, the term “Clean Ballast” as defined in the IBC Code means:
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Ballast water carried in a tank which, since it was last used to carry a cargo containing a substance in category “X”, “Y” or “Z”, has been thoroughly cleaned and the residues resulting there from have been discharged and the tank emptied in accordance with the appropriate requirements of Annex II