watchkeeping

Quick Guide to current

Sound and Light Signals
Condensed from the ©U.S. Coast Guard Navigation Rules, (part D only)
International – Inland: COMDTINST M16672.2D. Updated 2004*.

Part D - International / Inland
Sound and Light Signals, Rules 32 - 37
KEY:

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2

horn only

can use light with horn

Definitions
(a) whistle . . . . . . . . . . . . . . sound signaling blasts appliance (Annex III)
(b) - short blast. . . . . . . . . . 1 second duration
(c) — prolonged blast . . . . 4-6 second duration

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3

Equipment for Sound Signals
(a) vessel > 391/3 ft. shall have a whistle and bell (Annex III)
(b) vessel < 391/3 ft. shall have means of making efficient sound signal

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Maneuvering and Warning Signals
International
(a&b) - changing to STB (right)
- - changing to PORT (left) no response needed from other vessel

Inland
(a&b) - intend to go STB
- - intend to go PORT if in agreement, second vessel gives same signal
••••• if in doubt, 5 short, rapid blasts
- - - operating astern propulsion (international & inland)
(c) Overtaking – narrow channel/fairway
— — - intend to overtake to STB
- intend to overtake to STB
— — - - intend to overtake to PORT
- - intend to overtake to PORT
— - — - if in agreement, second if in agreement, second vessel gives this signal vessel returns same signal
(d) ••••• if in doubt, 5 short, rapid blasts (international & inland)
(e) Nearing bend / obscured
— if vessel has an obscured
— if vessel has an obscured field of vision field of vision any approaching vessel returns same signal (both international & inland)
(f) If whistles are 100+ meters apart, use only one for these signals
(g)
— when power-driven vessel leaves dock/berth

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Sound Signals in Restricted Visibility (international & inland)
In or near area of restricted visibility, day or night
(a) — if under Power Making Way (every 2 min.)
(b) — — if under Power Not Making Way (every 2 min.)
(c) — - - every 2