A vessel when at anchor must keep burning a white light, throwing an unbroken flare in every direction; this light should be hoisted above the deck the height of the vessel’s breadth.
All lights must be carried from sunset to sunrise; no other lights should be shown.
Fog Signals.
A steam vessel must be provided with a whistle operated by steam or air.
A sailing vessel must be provided with a horn.
In fog, mist, falling snow, or heavy rainstorms, whether by day or night, the signals described shall be used:
A steam vessel underway shall sound, at intervals of not more than one minute, a prolonged blast.
A sailing vessel underway shall sound, at intervals of not more than one minute, when on the starboard tack, one blast; when on the port tack, two blasts in succession, and when with the wind abaft the beam, three blasts in succession.
A vessel when at anchor shall, at intervals of not more than one minute, ring the bell rapidly for about five seconds.