Which COLREGs rules should be checked to determine if there is an impede relationship in restricted visibility?

• A. 9, 10, 18
• B. 3, 5, 7
• C. 12, 14, 16
• D. 20, 22, 24

Answer: (A)

In restricted visibility, the main concern is whether your vessel’s actions could impede another vessel’s safe passage. The rules you check to judge this are the ones that govern where vessels may operate and how to behave when visibility is poor.

First, Rule 9 deals with navigating in narrow channels or regimes where traffic is confined. It sets expectation for staying clear of oncoming traffic and choosing a safe path in restricted spaces, which helps you assess whether your movement could obstruct another vessel.

Second, Rule 10 covers traffic separation schemes. These lanes create predictable tracks for vessels; staying within the scheme and following its directions reduces the chance of forcing another vessel to take evasive action or being impeded by you.

Third, Rule 18 directly addresses conduct in restricted visibility. It requires proceeding at a safe speed appropriate to the conditions, maintaining a proper lookout, and taking early action to avoid collisions. This rule is where the concept of not impeding others is enforced in the specific context of limited visibility.

Together, these rules provide the framework for determining whether there is an impediment relationship in restricted visibility by focusing on where you can operate, how you should align with established traffic patterns, and how to adjust behavior to prevent hindering other vessels.