Excluded spaces. These are not included in the “gross tonnage”: e.g., dry cargo space above the upper deck, machinery spaces above the upper deck, wheelhouse, navigation spaces, galley, dedicated water ballast tanks above the upper deck and so on.
Such excluded spaces (except dry cargo space) must be certified by a surveyor to be reasonable in extent, properly constructed and permanently marked as to their purpose. Double bottom tanks are not spaces included in the gross tonnage.
