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Germanischer Lloyd


Global Maritime Distress and Safety System (GMDSS) developed by the IMO and comprising a number of key elements including: Call Sign (a unique identifier of a radio station);Maritime Mobile Service Identity (MMSI) (a nine digit which is transmitted over the radio path in order to uniquely identify ship stations, ship earth stations, coast stations, coast earth stations and group calls); Selective Call Number (a unique numeric identifier of a ship or coast station in the maritime mobile service for simplex teletype over radio);Mobile Earth Station Identification Number (MESIN) (a unique numeric identifier of an INMARSAT-C, INMARSAT-M, INMARSAT-B and all new INMARSAT ship earth station);Ship Earth Station Identity Number (a unique numeric identifier of an INMARSAT-A ship earth station); Ship Station Identity (a unique numeric identifier of an INMARSAT-E EPIRB); and 406 MHZ EPIRB Unique Identifier Number (a unique alphanumeric identifier of a 406 MHZ satellite EPIRB).


Gross tonnage is the total volume of all enclosed spaces of a ship usable for carrying cargo or passengers measured in cubic metres using a standard formula under the International Tonnage Convention for vessels 24 metres and above or under national regulations for ships under 24 metres in length. See also DWT.