What should vessels do if visibility is poor and a distress signal is observed?

When visibility is poor and a distress signal is observed, the appropriate response is to proceed with caution and slow down to assess the situation. This approach ensures that the vessel can navigate safely while still being vigilant to potential dangers, such as unseen obstacles or other vessels. Slowing down allows the crew to better evaluate the distress signal, determine the best course of action, and avoid contributing to a hazardous situation.

Maintaining a cautious speed is critical in conditions of poor visibility. It allows for quicker reaction times in case of any unexpected developments while ensuring that the vessel is not operating at a speed that could lead to accidents. Assessing the situation gives the responding vessel the opportunity to correctly identify the nature of the distress signal and determine the most effective means of providing assistance, if needed.

Other responses, like proceeding at full speed or ignoring the signal, could lead to increased risks to both the responding vessel and those in distress. Furthermore, altering course away from the signal would not be an appropriate response, as it neglects the responsibility to assist others in need when a distress signal is observed.