Do the light rules apply in daytime, and what about a vessel restricted from keeping a good lookout?

Q: Do the light rules apply in daytime, and what about a vessel restricted from keeping a good lookout?

Rule 20: lights shall be exhibited from sunset to sunrise, and in restricted visibility (and may be shown in all other circumstances when considered necessary). Shapes are exhibited by day. The Rules on lights must be complied with in all weathers. Lead: lights sunset–sunrise and in RV; shapes by day.

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Part C · Lights and shapes

COLREGS Rule 20 — Application

(a) Rules in this Part shall be complied with in all weathers.

(b) The Rules concerning lights shall be complied with from sunset to sunrise, and during such times no other lights shall be exhibited, except such lights as cannot be mistaken for the lights specified in these Rules or do not impair their visibility or distinctive character, or interfere with the keeping of a proper look-out.

(c) The lights prescribed by these Rules shall, if carried, also be exhibited from sunrise to sunset in restricted visibility and may be exhibited in all other circumstances when it is deemed necessary.

(d) The Rules concerning shapes shall be complied with by day.

(e) The lights and shapes specified in these Rules shall comply with the provisions of Annex I to these Regulations.

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Rule 20

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Rule 20: lights shall be exhibited from sunset to sunrise, and in restricted visibility (and may be shown in all other circumstances when considered necessary). Shapes are exhibited by day. The Rules on lights must be complied with in all weathers.Lead · lights sunset–sunrise and in RV; shapes by day.

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All COLREGS Rules and Annexes

Part A · General

Part B · Steering and sailing rules

Part C · Lights and shapes

Part D · Sound and light signals

Part E · Exemptions

Rule 38 — Exemptions

Part F · Verification of compliance

Annex I · Positioning and technical details of lights and shapes

Annex II · Additional signals for fishing vessels fishing in close proximity

Annex III · Technical details of sound signal appliances

Annex IV

Annex IV — Distress Signals

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