Securité

When a marine radio transmission begins with the phrase "Sécurité, sécurité, sécurité" (/seɪˈkjʊərᵻteɪ/; French: sécurité), it means that what follows is important safety information. The most common use of this is by coast radio stations before the broadcast of navigational warnings and meteorological information.

Navigational warnings are issued regularly and usually give information about people or vessels in distress and objects or events that can be an immediate danger to people at sea and how they are navigating. In the United States, MARAD (Marine Administration) sends out infrequent advisories about potential global political climate dangers. There are four types of navigational warnings, which are categorized by their location. These areas are NAVAREA IV, HYDROLANT, NAVAREA XII, and HYDROPAC.

Meteorological information is information that is about the marine atmosphere. These meteorological advisories include the development of weather systems such as and not limited to, rain squalls, big tidal drops, major current shifts, lightning storms, hurricane and tsunami warnings, high winds, and cyclones.

It is normal practice to broadcast the Sécurité call itself on a distress and listening frequency such as VHF Channel 16 or MF 2182 kHz, and then change frequency to a working channel for the body of the messages. An equivalent Morse code signal is TTT, with each letter sent distinctly.

Although mostly used by coast radio stations, there is nothing to stop individual craft broadcasting their own Sécurité messages where appropriate, for example, a yacht becalmed (rendered motionless for lack of wind), or any vessel adrift or unable to manoeuvre near other craft or shipping lanes.

Of the three distress and urgency calls, Sécurité is the least urgent.

Securite: A radio call that usually issues navigational warnings, meteorological warnings,and any other warning needing to be issued that may concern the safety of life at sea, yet may not be particularly life-threatening.

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