• Not making way — sound two prolonged
blasts at intervals of not more than 2 minutes.
• Not under command, or restricted in its
ability to maneuver, vessel engaged in
fi shing, vessel towing — one prolonged
blast followed by two short blasts at intervals
of not more than two minutes.
Sailing Vessel
Sound one prolonged blast followed by two
short blasts every two minutes (or less).
Vessels at Anchor
• Boats less than 65.6 feet (20 meters) use
any effi cient sound device with an interval
no more than 2 minutes.
• If you see a vessel approaching, you may
also sound short, prolonged, short blasts
in quick succession.
• Other vessels at anchor, ring bell approx.
5 seconds at intervals of 1 minute or less;
over 100 meters sound at forepart of the
vessel immediately followed by rapid
sound of the gong aft for about 5 seconds,
the tone and sound of which cannot be
confused with that of the bell.
The following vessels shall not be required
to sound signals when in a USCG-approved
anchorage area: a vessel less than 20 meters
in length; or a barge, canal boat, scow, or
other nondescript craft (Table 6-5).
Section 6: Lights and Sound Signals 83
Table 6-5. Sound Signals Anchored in Restricted Visibility
Vessel Length Signal Required
Any effifi effi cient sound signal
signal
device sounded at intervals of
not more than 2 minutes
Ring bell rapidly for. 5
seconds every minute
All vessels May supplement with 3
whistle blasts, short-prolongshort,
Alternative to
Sound Signals
A vessel aground of 100m or less shall
sound the signals of a vessel at anchor
plus shall, in addition, give three separate
and distinct strokes on the bell immediately
before and after the rapid ringing of
the bell. A vessel aground may in addition
sound an appropriate whistle signal.
A vessel that reaches agreement with
another vessel in a head on, crossing, or
overtaking situation, by using the radiotelephone
is not obliged to sound the
whistle signals prescribed by this rule, but
may do so. If agreement is not reached,
then whistle signals shall be exchanged in a
timely manner and shall prevail.
to warn approaching
vessels.
90
91
92
93
94
95
96
97
98
Tip: Hint for remembering shortprolonged
short is “S-P-S” for ship position
stationary.
Vessels under 20
meters/65.60 feet
Vessels 20 meters to 100
meters/328.1 feet
Vessels over 100 meters Ring bell and gong rapidly
for 5 seconds every minute.