29.1 The phrase “large quantities of oil
fuel” in regulation 16.2 refers
to ships which are required to stay at sea for extended periods because
of the particular nature of their operation and trade. Under the circumstances
considered, these ships would be required to fill their empty oil
fuel tanks with water ballast in order to maintain sufficient stability
and safe navigation conditions.
29.2 Such ships may include inter alia certain
large fishing vessels or ocean-going tugs. Certain other types of
ships which for reasons of safety, such as stability, may be required
to carry ballast in oil fuel tanks may also be included in this category.