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*** Special Notice: *** Please be advised that our mailing address has changed and is now: U.S. Coast Guard Navigation Center, NAVCEN MS 7310, 7323 Telegraph Road, Alexandria, VA 20598 - 7310. Mail sent to our previous address will not be delivered. Please contact us with concerns or questions. Our physical location remains the same. Thank you for your attention to this matter.
Maritime Telecomms
Primary Mission Areas:
Maritime Information:
MARITIME TELECOMMUNICATIONS

Although telecommunications technology is improving quickly, people at sea do not have access to the same telecommunications infrastructure people ashore have. Like people ashore, Mariners need to access international shore telephone and data public switched networks. Additionally they need to access many maritime specific communications listed below:

  • Mariners need to be able to communicate with other ships of any size or nationality.
  • Mariners need to be able to receive and send urgent maritime safety information.
  • Mariners need to be able to send or receive distress alerts in an emergency to or from rescue coordination centers ashore and nearby ships anywhere in the world.

Maritime telecommunications systems must be internationally interoperable. Bringing new telecommunications technology to mariners can be difficult, since to be interoperable, the technology must be affordable, acceptable and available to most ships and maritime countries.

The Coast Guard does not advocate cellular telephones as substitute for the regular maritime radio distress and safety systems recognized by the Federal Communications Commission and the International Radio Regulations -- particularly VHF maritime radio.  However, cellular phones can have a place on board as an added measure of safety.

CELLULAR PHONE LIMITATIONS IN AN EMERGENCY

  • Cellular phones generally cannot provide ship to ship safety communications or communications with rescue make a distress call on a cellular phone, only the one party you call will be able to hear you.
  • Most cellular phones are designed for a land-based service. Their coverage offshore is limited, and may change without notice.
  • Locating a cellular caller is hard to do.  If you don't know precisely where you are, the Coast Guard will have difficulty finding your location on the water.

(Ref. U.S. Coast Guard  --  CONSUMER FACT SHEET)

Two United Nations-chartered organizations, the International Maritime Organization and the International Telecommunications Union, are responsible for defining and regulating maritime telecommunications systems. The most current system adopted by these two organizations is the Global Maritime Distress and Safety System, or GMDSS.  Morse wireless telegraphy, used by ships for distress and safety communications since the beginning of the century, was discontinued by the USCG in 1995, and ceased worldwide on February 1, 1999.  Many people owe their lives to this system.

The links on the left will lead you to several informative sections regarding Maritime Telecommunications, including the Universal Shipborne Automatic Identification System, Digital Selective Calling, the Global Maritime Distress and Safety Systems, and much more.