Rule 9

Narrow channels

Any visibility

Keep as near the starboard outer limit of the channel as is safe — small craft, sailboats, and fishing vessels must not impede.

Narrow channel, Rule 9A channel runs up the page between two shaded banks. An upbound vessel keeps to the right-hand edge of the channel and a downbound vessel keeps to her own right-hand edge, so the two meet port to port. A dashed line marks the middle of the channel.upboundkeeps to her starboard edgedownboundkeeps to her starboard edgethey meet port to port
Rule 9(a) — in a narrow channel or fairway, each vessel keeps as near the outer limit on her own starboard side as is safe and practicable, so opposing traffic meets port to port.

In plain language

In a narrow channel, drive on the right: keep as close to the channel edge on your starboard side as is safe and practicable. Vessels under 20 m, sailing vessels, and vessels crossing the channel must not impede a vessel that can only navigate safely inside it; a vessel engaged in fishing must not impede the passage of any other vessel navigating within the channel at all. Approaching a blind bend, sound the bend signal and proceed with particular alertness — and avoid anchoring in a channel at all.

This rule differs under the US Inland Rules. Change the rule set in language and regional settings to see the difference.

Easily confused with