This means that search and rescue efforts may normally be suspended when:
- no communications with the distressed vessel can be established,
- no further information or means of contacting the vessel can be obtained from other sources, and
- no position information is known.
The Coast Guard has issued a marine safety alert that advises:
FIRST Obtain a Maritime Maritime Mobile Installation Identity (MMSI) and enter it into your radio. MMSI numbers are issued by the Federal Communications Commission if your vessel otherwise requires a station license, or BOATUS, (http://www.boatus.com/mmsi), Sea Tow (http://www.seatow.com/mmsi), or the U.S. Power Squadrons (http://www.usps.org/php/mmsi). Ensure any information originally provided is updated as changes occur. FCC regulations require that DSC-equipped radios "use MMSIs assigned by the Commission or its designees" (47 CFR 80.103(b)).
THEN Interconnect your radio to a GPS receiver using a two-wire NMEA 0183 interface on all DSC-equipped marine radios and on most GPS receivers. Instructions should be provided in the radio and GPS operators manual. Further information is provided and will be routinely updated in http://www.navcen.uscg.gov/?pageName=mtDsc.
September 2, 2011