Part B · Section I

COLREGs Rule 4: Application of Section I

Rule 4 says the rules in Section I of Part B (Rules 5 to 10: look-out, safe speed, risk of collision, action to avoid collision, narrow channels and traffic separation schemes) apply in any condition of visibility.

What Rule 4 says

  1. Rules 5 to 10 apply in any condition of visibility: in clear weather, at night and in fog.

This is a plain-English summary, not the official wording. For the exact text, see the IMO convention. In UK waters the rules are given legal force by the Merchant Shipping (Distress Signals and Prevention of Collisions) Regulations.

What it means on a yacht

Look-out, safe speed and the narrow-channel and TSS rules never switch off. Whatever the weather, these apply on every passage.

Practise it

Test yourself on who gives way in the free COLREGs trainer, or print the rules of the road cheat sheets for the chart table.

Other rules in Part B