The Coast Guard reminds all boaters that as of January 1, 2007 the use of both 121.5 and 243 MHz Emergency Position Indicating Radio Beacons (EPIRBs) is prohibited.  The January 1 stop date is in preparation for February 1, 2009 (the actual date satellite processing of distress signals from all 121.5/243 MHz beacons will terminate) after which only 406 MHz beacons will be detected by the International Cospas-Sarsat Satellite System, which provides distress alert and location data for search and rescue operations around the world.

The above requirement applies to all Class A, B, and S 121.5/243 MHz EPIRBs, however 121.5/243 MHz man overboard devices designed to work directly with a base alerting unit (and not with the satellite system) are exempt.

Unreliability of the 121.5/243 MHz beacons is the man cause for the change typically only one out of every 50 alerts received from 121.5/243 MHz beacons is a genuine distress situation. With 406 MHz beacons, false alerts have been reduced significantly and when properly registered, can usually be resolved with a telephone call to the beacon owner.  This registration database includes the beacon owner's contact information, emergency contact information, and vessel/aircraft identifying characteristics. Having this information allows the Coast Guard or other rescue personnel to respond appropriately.

EPIRB owners in the US are required by law to register their beacon in the U.S. 406 MHz Beacon Registration Database at: or by calling 1-888-212-SAVE. Other users can register their beacon in their country's national beacon registration database or, if no national database is available, in the International Beacon Registration Database at