IALACOLREG
19

Conduct of Vessels in Restricted Visibility

In restricted visibility, vessels detected by radar alone must take avoiding action in ample time. Avoid altering to port for a vessel forward of the beam.

Rule 19 applies to vessels not in sight of one another when navigating in or near an area of restricted visibility.

a
Every vessel shall proceed at a safe speed adapted to the conditions and have engines ready for immediate manoeuvre.
b
Every vessel shall have due regard to the prevailing circumstances and conditions of restricted visibility when applying Rules 4 to 10.
c
A vessel detecting another by radar alone shall determine whether a close-quarters situation or risk of collision is developing. If so, she shall take avoiding action in ample time.
d
If the avoiding action consists of an alteration of course, so far as possible avoid:
  • 1altering to port for a vessel forward of the beam, other than for a vessel being overtaken
  • 2altering towards a vessel abeam or abaft the beam
e
A vessel that hears a fog signal apparently forward of the beam, or cannot avoid a close-quarters situation with a vessel forward of the beam, shall reduce speed to the minimum at which she can be kept on course and, if necessary, take all way off. She shall then navigate with extreme caution until danger of collision is over.

STCW Bridge Watch Lens

1

Restricted visibility watchkeeping is a package: inform the master, post a proper look-out, exhibit the correct lights, have engines ready and operate radar effectively.

2

Avoid the instinctive port alteration for a target forward of the beam. Slow down, reassess and keep the contact under systematic observation.

3

After manoeuvring, keep monitoring bearing, range, CPA/TCPA and passing distance until the other vessel is finally past and clear.

Exam Focus

1

Start every scenario by classifying the encounter: overtaking, head-on, crossing, narrow channel, traffic separation, or restricted visibility.

2

If two rules seem to conflict, check the order carefully: overtaking duties still apply, and Rule 2 still requires ordinary seamanship.

3

Rule 19 does not create stand-on and give-way vessels. If the vessels are not in sight of one another, do not apply the crossing or head-on rules.

Key Takeaways

1

Rule 19 applies when vessels are not visually in sight of one another

2

There is no stand-on vessel under Rule 19; every ship must assess and manoeuvre prudently

3

Avoid the instinctive port alteration for a radar target forward of the beam

4

If necessary, take all way off and continue with extreme caution until the danger has passed

Common Mistakes

Applying the crossing or head-on rules to radar-only contacts

Keeping too much speed after hearing a fog signal ahead

Turning toward a contact that is already abeam or abaft the beam

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