What requirement does Rule 4 of COLREGs emphasize?

Rule 4 of the COLREGs emphasizes the need for vessels to take action to avoid collisions. This rule is essential because it establishes the fundamental responsibility of all mariners to navigate safely and prevent collisions at sea. It recognizes that regardless of the circumstances, the operator must take appropriate measures when there is a risk of collision. This may include altering course or speed, taking preventive measures, and being vigilant in assessing the situation to ensure safety.

While other options mention important aspects of navigation, such as technology and vessel stability, they do not directly address the critical nature of active prevention of collisions, which is central to Rule 4. The rule prioritizes actions to be taken, ensuring that navigators remain proactive and responsible in maintaining safety on the water. The focus is on the requirement that all vessels must act whenever there is a risk of collision, fostering a culture of vigilance and responsibility in maritime operations.