COLREG Rule 19 — Restricted Visibility
Conduct of vessels in or near restricted visibility — early action, safe speed, and avoidance of port-side alterations to a vessel forward of the beam.
In practice
OOW operates in fog: reduced speed, engines on standby, fog signal sounded, radar plots maintained. Avoid alteration to port for vessels forward of the beam unless overtaking.
Regulatory detail & full definition
COLREG Rule 19 — Conduct of Vessels in Restricted Visibility: applies to vessels not in sight of one another when navigating in or near an area of restricted visibility. Each shall proceed at a safe speed (Rule 6) with engines ready for immediate manoeuvre. When detecting another vessel by radar alone, take avoiding action in ample time, avoiding (so far as possible) an alteration of course to port for a vessel forward of the beam (other than overtaking) or alteration of course toward a vessel abeam or abaft the beam.
Authoritative source: COLREG 1972 ↗
Related
Source: COLREG 1972 Rule 19
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