When is ballast water most likely to be introduced into empty cargo tanks?

The introduction of ballast water into empty cargo tanks is most likely to occur during heavy weather. In conditions of rough seas or adverse weather, a vessel may require ballast water to maintain stability and reduce excessive rolling or pitching. Adding ballast helps to stabilize the ship, ensuring safer navigation and preventing potential damage to the ship or cargo.

Heavy weather can significantly impact the ship's maneuverability and safety, thus prompting the crew to take measures such as introducing ballast water into tanks that are otherwise empty. The other circumstances, such as loading or cleaning, do not typically require immediate addition of ballast to maintain stability, and departure often occurs with the ship already prepared and ballasted as necessary for safe transit.