Under which scenario is it permissible to depart from the COLREGs?

• A. When you are head-on with another PDV and you are constrained by land on the starboard side, making an alteration to starboard impossible
• B. When you are overtaking another vessel
• C. When there is no danger of collision
• D. When you are negotiating a tow

Answer: (A)

The key idea here is that the COLREGs must be followed, but you may take action to avoid collision even if that means temporarily departing from a specific rule. That exception only applies when there is an immediate danger and no safe way to comply with the Rules as written.

In a head-on situation, the standard action is to alter course to starboard so you pass on each other’s port sides. If you’re bordered by land on the starboard side and cannot make that starboard alteration, you cannot carry out the required maneuver. The safety priority then is to take any reasonable action to avoid a collision, even if that means deviating from the exact rule. This is why the scenario describes a permissible departure from the COLREGs.

If there is no danger of collision, or if you’re simply overtaking or negotiating a tow under normal conditions, there’s no justification to depart from the Rules—their application remains the proper course.