On which side should power-driven vessels typically pass each other?

Power-driven vessels typically pass each other on the port side as per maritime navigation practices and regulations. This convention is rooted in promoting safety and reducing the risk of collision at sea. When two vessels encounter one another head-on or near head-on, it is generally expected that each vessel will maintain a course and speed while passing each other on their port sides. This ensures a clear and predictable maneuver for both vessels, allowing them to maintain a safe distance apart while avoiding confusion in navigation.

Although there may be instances where vessels can agree to pass on either side, the practice of passing on the port side is a standard rule that helps establish a common understanding among mariners. This reduces the chances of accidents that could arise from inconsistent passing practices, especially in situations where visibility is limited or when multiple vessels are navigating a confined space.