[Code of Federal Regulations]
[Title 33, Volume 1]
[Revised as of July 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 33CFR62.23]

[Page 145]
 
                TITLE 33--NAVIGATION AND NAVIGABLE WATERS
 
         CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY
 
PART 62--UNITED STATES AIDS TO NAVIGATION SYSTEM--Table of Contents
 
              Subpart B--The U.S. Aids to Navigation System
 
Sec. 62.23  Beacons and buoys.

    (a) Aids to navigation are placed on shore or on marine sites to 
assist a navigator to determine his position or safe course. They may 
mark limits of navigable channels, or warn of dangers or obstructions to 
navigation. The primary components of the U.S. Aids to Navigation System 
are beacons and buoys.
    (b) Beacons are aids to navigation structures which are permanently 
fixed to the earth's surface. They range from large lighthouses to 
small, single-pile structures and may be located on land or in the 
water. Lighted beacons are called lights; unlighted beacons are called 
daybeacons.
    (1) Beacons exhibit a daymark. For small structures these are 
colored geometric shapes which make an aid to navigation readily visible 
and easily identifiable against background conditions. Generally, the 
daymark conveys to the mariner, during daylight hours, the same 
significance as does the aid's light or reflector at night. The daymark 
of large lighthouses and towers, however, consists of the structure 
itself. As a result, these daymarks do not infer lateral significance.
    (2) Vessels should not pass beacons close aboard due to the danger 
of collision with rip-rap or structure foundations, or the obstruction 
or danger that the aid marks.
    (c) Buoys are floating aids to navigation used extensively 
throughout U.S. waters. They are moored to the seabed by sinkers with 
chain or other moorings of various lengths.
    (1) The daymark of a buoy is the color and shape of the buoy and, if 
so equipped, of the topmark.
    (i) Can buoys have a cylindrical shape.
    (ii) Nun buoys have a tapered, conical shape.
    (iii) Pillar buoys have a wide cylindrical base supporting a 
narrower superstructure. They may be surmounted by colored shapes called 
topmarks.
    (iv) Spherical buoys have a round shape.
    (2) Mariners attempting to pass a buoy close aboard risk collision 
with a yawing buoy, the buoy's mooring, or with the obstruction which 
the buoy marks.
    (3) Mariners should not rely on buoys alone for determining their 
positions due to factors limiting their reliability. Prudent mariners 
will use bearings or angles from beacons or other landmarks, soundings, 
and various methods of electronic navigation. Buoys vary in reliability 
because:
    (i) Buoy positions represented on nautical charts are approximate 
positions only, due to practical limitations in positioning and 
maintaining buoys and their sinkers in precise geographical locations.
    (ii) Buoy moorings vary in length. The mooring lengths define a 
``watch circle'', and buoys can be expected to move within this circle. 
Actual watch circles do not coincide with the dots or circles 
representing them on charts.
    (iii) Buoy positions are normally verified during periodic 
maintenance visits. Between visits, environmental conditions, including 
atmospheric and sea conditions, and seabed slope and composition, may 
shift buoys off their charted positions. Also buoys may be dragged off 
station, sunk, or capsized by a collision with a vessel.

[CGD 86-031, 52 FR 42640, Nov. 6, 1987; CGD 86-031, 52 FR 46351, Dec. 5, 
1987]