Maritime Safety Maritime Safety Information Under Information Under
the GMDSSthe GMDSS
BackgroundBackground The GMDSS makes specific The GMDSS makes specific
requirements with regard to requirements with regard to radio equipment, and ships must radio equipment, and ships must be able to carry out several be able to carry out several different functions, one of which different functions, one of which is the ability to TRANSMIT and is the ability to TRANSMIT and RECEIVE Maritime Safety RECEIVE Maritime Safety Information (MSI)Information (MSI)
Maritime Safety Information Maritime Safety Information (MSI)(MSI)
Navigational reportsNavigational reports Meteorological reportsMeteorological reports Weather ForecastsWeather Forecasts Messages of General ImportanceMessages of General Importance
MSI is transmitted via the ff:MSI is transmitted via the ff: NAVTEXNAVTEX Inmarsat EGC systemInmarsat EGC system Radio Telex (NBDP)Radio Telex (NBDP) Radio telephony (Safety Radio telephony (Safety
Messages)Messages)
Navtex system MSINavtex system MSI
The NAVTEX SystemThe NAVTEX System Navtex system could reach up to a Navtex system could reach up to a
distance 600 nm offshore.distance 600 nm offshore. 518 kHz is the International navtex 518 kHz is the International navtex
frequencyfrequency 24 Navtex stations in one NAVAREA24 Navtex stations in one NAVAREA The 24 stations are divided into 4 The 24 stations are divided into 4
groups consisting of 6 transmitting groups consisting of 6 transmitting stations.stations.
Every group is allowed one hour Every group is allowed one hour transmission time. (10mins/4 hours)transmission time. (10mins/4 hours)
NavareasNavareas There are 16 Navareas worldwide. There are 16 Navareas worldwide. Navtex stations are geographically Navtex stations are geographically
separated.separated. Every Navtex station has its own Every Navtex station has its own
identification character (A-Z).identification character (A-Z). Navtex stations coverage is shown in Navtex stations coverage is shown in
the ITU “List of Radio Determination the ITU “List of Radio Determination and Special Service Stations”and Special Service Stations”
The Navtex coordinator in each The Navtex coordinator in each Navarea decides which MSI messages Navarea decides which MSI messages the system is to broadcast.the system is to broadcast.
Navtex Stations WorldwideNavtex Stations Worldwide
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The Navtex CoordinatorThe Navtex Coordinator• Coastguard
• Buoyage authority• Electronic Navaids• Offshore Operator• Government dept.
• Ship reports• NAVAREA co-ordinator
• National Coordinator
Ice Monitoring meteorological
offices
Initial distress message
Navigational warning co-ordinator
Meteorological message co-ordinator
SAR co-ordinator
NAVTEX coordinator
Transmitter
Building up a Navtex messageBuilding up a Navtex message
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ZCZC B1 B2 B3 B4
Message Origin …….
……………………..
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The Subject Indicators (B2)The Subject Indicators (B2)AA = Navigational Warnings (cannot be rejected by the = Navigational Warnings (cannot be rejected by the
receiver)receiver)BB = Meteorological Warnings (cannot be rejected by the = Meteorological Warnings (cannot be rejected by the
receiver)receiver)C C = Ice Reports= Ice ReportsD D = Search and Rescue information (cannot be rejected = Search and Rescue information (cannot be rejected by by the receiver)the receiver)E E = Meteorological Forecasts= Meteorological ForecastsF F = Pilot Service Messages= Pilot Service MessagesG G = DECCA Messages= DECCA MessagesH H = LORAN Messages= LORAN MessagesI I = OMEGA Messages= OMEGA MessagesJ J = SATNAV Messages= SATNAV MessagesKK = Other Electronic Navaid Messages (messages = Other Electronic Navaid Messages (messages concerning concerning radio navigation services)radio navigation services)LL = Navigational Warnings for mobile drilling rig = Navigational Warnings for mobile drilling rig movements movements (cannot be rejected by the receiver)(cannot be rejected by the receiver)V V = Amplifying navigational warning information = Amplifying navigational warning information initially initially announced under “A”announced under “A”ZZ = No messages on hand = No messages on hand
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ZCZC GA20
ORKNEY ISLANDS
LOTHER ROCK RACON 58.44N 02.49W
TEMPORARILY OFF AIR
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ZCZC GL67
RIGMOVE. SOUTHERN NORTHSEA. “CHARLES ROWAN” AT 54-19N 02-07.7E CANCEL THIS MESSAGE 121020 Z FEB 25
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ZCZC PB68
NETHERLANDS COASTGUARD GALE WARNING NR. 55 180630 FEB DOVER THAMES – SOUTH 8 OTHER DISTRICTS – NO WARNINGS
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