(a) The navigable waters of the United States and non-navigable State waters after December 31, 2003, are marked to assist navigation using the U.S. Aids to Navigation System, a system consistent with the International Association of Lighthouse Authorities (IALA) Maritime Buoyage System. The IALA Maritime Buoyage System is followed by most of the world's maritime nations and will improve maritime safety by encouraging conformity in buoyage systems worldwide. IALA buoyage is divided into two regions made up of Region A and Region B. All navigable waters of the United States follow IALA Region B, except U.S. possessions west of the International Date Line and south of 10 degrees north latitude, which follow IALA Region A. Lateral aids to navigation in Region A vary from those described throughout this Subpart. Non-lateral aids to navigation are the same as those used in Region B. See § 62.25. Appropriate nautical charts and publications should be consulted to determine whether the Region A or Region B marking schemes are in effect for a given area.

(b) The U.S. Aids to Navigation System is designed for use with nautical charts. Nautical charts portray the physical features of the marine environment, including soundings and other submarine features, landmarks, and other aids necessary for the proper navigation of a vessel. This crucial information cannot be obtained from other sources, even ones such as topographic maps, aeronautical charts, or atlases. The exact meaning of an aid to navigation may not be clear to the mariner unless the appropriate chart is consulted, as the chart illustrates the relationship of the individual aid to navigation to channel limits, obstructions, hazards to navigation, and to the total aids to navigation system.

(c) The navigator should maintain and consult suitable publications and instruments for navigation depending on the vessel's requirements. This shipboard equipment is separate from the aids to navigation system, but is often essential to its use. The following publications are available from the U.S. Government to assist the navigator:

(1) The Light List, published by the Coast Guard and available for viewing on the Coast Guard Navigation Center Web site at http://www.navcen.uscg.gov lists federal and private aids to navigation. It includes all major Federal aids to navigation and those private aids to navigation that have been deemed to be important to general navigation, and includes a physical description of these aids and their locations.

(2) The United States Coast Pilot, published by the National Ocean Service and available from NOAA Certified Printer Partners listed at http://www.nauticalcharts.noaa.gov/mcd/NOAAChartViewer.html. Free on-line versions and weekly updates supplement the information shown on nautical charts, and are available directly from NOAA at http://www.nauticalcharts.noaa.gov/nsd/cpdownload.htm. Subjects such as local navigation regulations, channel and anchorage peculiarities, dangers, climatalogical data, routes, and port facilities are covered.

(3) Local Notices to Mariners are published by local Coast Guard District Commanders. Persons may view Local Notices to Mariners on the Coast Guard Navigation Center Web site at http://www.navcen.uscg.gov. Changes to aids to navigation, reported dangers, scheduled construction or other disruptions, chart corrections and similar useful marine information is made available through this publication.

(4) The Notice to Mariners is a national publication, similar to the Local Notice to Mariners, published by the National Geospatial-Intelligence Agency. The notices may be viewed on the National Geospatial-Intelligence Agency's Web site at http://msi.nga.mil/NGAPortal/MSI.portal. This publication provides oceangoing vessels significant information on national and international navigation and safety.

(5) The mariner should also listen to Coast Guard Broadcast Notices to Mariners. These broadcasts update the Local Notice to Mariners with more timely information. Mariners should monitor VHF-FM channel 16 to locate Coast Guard Marine Information Broadcasts.

(d) The U.S. Aids to Navigation System is primarily a lateral system which employs a simple arrangement of colors, shapes, numbers, and light characteristics to mark the limits of navigable routes. This lateral system is supplemented by nonlateral aids to navigation where appropriate.

(e) Generally, lateral aids to navigation indicate on which side of a vessel an aid to navigation should be passed when the vessel is proceeding in the Conventional Direction of Buoyage. Normally, the Conventional Direction of Buoyage is the direction in which a vessel enters navigable channels from seaward and proceeds towards the head of navigation. In the absence of a route leading from seaward, the Conventional Direction of Buoyage generally follows a clockwise direction around land masses. For example, proceeding southerly along the Atlantic Coast, from Florida to Texas along the Gulf Coast, and northerly along the Pacific Coast are considered as proceeding in the Conventional Direction of Buoyage. In some instances, this direction must be arbitrarily assigned. Where doubt exists, the mariner should consult charts and other nautical publications.

(f) Although aids to navigation are maintained to a reasonable degree of reliability, the rigors of the marine environment and various equipment failures do cause discrepancies on occasion.

(g) The Coast Guard makes reasonable efforts to inform the navigator of known discrepancies, and to correct them within a reasonable period of time, depending upon resources available. Occasionally, a temporary aid to navigation, which provides different but similar service, is deployed until permanent repairs can be made to the original aid. Notification of such temporary changes is made through the notice to mariners system.

(h) Mariners should exercise caution when using private aids to navigation because private aids are often established to serve the needs of specific users rather than general navigation and their purpose may not be obvious to casual users; and, discrepancies to private aids are often detected, reported, and corrected less promptly than discrepancies to Coast Guard aids to navigation.