What is the requirement stated in Watchstanding Principle 4 regarding leave from the watch station?

Watchstanding Principle 4 emphasizes the importance of ensuring that operational responsibilities are maintained at all times, which is why the requirement states that leaving a watch station is only permitted if the watchstander is properly relieved. This principle underscores the need for continuity and safety in operations, which can be compromised if a watchstander leaves without ensuring that someone else is in position to assume their duties.

The need for proper relief is critical to prevent lapses in monitoring and control over the tasks assigned to the watchstander, maintaining vigilance necessary for mission success and safety. Therefore, proper relief involves a clear handover of responsibilities to a qualified individual who can effectively continue the tasks required at the watch station.