Which situation requires immediate attention when operating cargo transfer on a tank vessel?

When operating cargo transfer on a tank vessel, the presence of a fire on the deck demands immediate attention because it poses a serious risk to the safety of the crew, the vessel, and the surrounding environment. In the context of handling flammable cargo, even a small flame can lead to catastrophic consequences. The priority in such a situation is to mitigate the danger, ensure crew safety, and protect the integrity of the vessel and its cargo. This could involve activating onboard fire suppression systems, alerting the crew, and potentially preparing to abandon the vessel if the fire cannot be controlled.

In contrast, calm weather conditions do not require immediate attention during cargo operations; rather, stable weather can facilitate safe transfer. A crew on break may indicate a need for proper scheduling, but it doesn’t present an immediate operational hazard unless key personnel are unavailable in a critical situation. Finally, while a tank at capacity requires monitoring to avoid overflow during loading operations, it is not an emergency situation demanding immediate action unless it compromises safety or threatens to exceed operational limits. Thus, the presence of a fire is the only scenario that necessitates urgent response.