Distress, urgency and safety calls: Mayday, Pan-Pan and Sécurité

1. 1Decide that the situation meets the distress threshold.
2. 2Select the DSC channel: Channel 70 on VHF or 2187.5 kHz on MF, if the equipment does not do it automatically.
3. 3If there is time, select the nature of distress, check the position and time, and confirm that the follow-on communication is telephony.
4. 4Transmit the alert (lift the cover, press and hold the distress button).
5. 5Prepare the voice traffic straight away: Channel 16 on VHF or 2182 kHz on MF, while watching for the acknowledgement.
6. 6Start the MAYDAY call and message by voice on Channel 16 or 2182 kHz as soon as possible after the alert. Do not hold it back waiting for the DSC acknowledgement; repeat the alert if no one answers.

The aim is not elegance; it is unambiguous information that a station tuning in late can still understand.

1. 1MAYDAY.
2. 2Ship identification: name, call sign and MMSI as the procedure requires.
3. 3Position, clearly, with the time if it is not current.
4. 4Nature of distress.
5. 5Assistance required.
6. 6Persons on board and other useful information: abandoning, liferafts, course and speed, vessel description.
7. 7OVER.

Model: MAYDAY MAYDAY MAYDAY. THIS IS TRAMUNTANA, TRAMUNTANA, TRAMUNTANA. CALL SIGN ECHO ALFA BRAVO CHARLIE, MMSI 224123456. MAYDAY TRAMUNTANA, CALL SIGN ECHO ALFA BRAVO CHARLIE, MMSI 224123456. POSITION 40 DEGREES 48.2 MINUTES NORTH, 001 DEGREE 05.4 MINUTES EAST. FIRE IN ENGINE ROOM, OUT OF CONTROL. REQUIRE IMMEDIATE ASSISTANCE. 18 PERSONS ON BOARD. PREPARING TO ABANDON SHIP. OVER.

A distress relay passes on the distress of someone else. It is needed when the casualty cannot alert, when its alert has not reached a SAR authority, or when the master judges more help is needed. The preferred addressee is a coast station or RCC when the aim is to get the alert ashore.

MAYDAY RELAY model: MAYDAY RELAY, MAYDAY RELAY, MAYDAY RELAY. VALENCIA RADIO, VALENCIA RADIO, VALENCIA RADIO. THIS IS BOREAL, BOREAL, BOREAL, CALL SIGN ECHO BRAVO OSCAR ROMEO, MMSI 224987654. FOLLOWING RECEIVED FROM FISHING VESSEL MARINA AT 1420 UTC. MAYDAY MARINA. POSITION 39 DEGREES 12 MINUTES NORTH, 000 DEGREES 05 MINUTES EAST. TAKING WATER, SINKING. 4 PERSONS ON BOARD. OVER.

A ship that can help acknowledges a distress message by voice in this order: MAYDAY, the casualty's identity three times, THIS IS, its own identity three times, RECEIVED MAYDAY. Then it gives its position, speed and ETA when asked.

Voice acknowledgement model: MAYDAY. TRAMUNTANA, TRAMUNTANA, TRAMUNTANA, MMSI 224123456. THIS IS BOREAL, BOREAL, BOREAL, CALL SIGN ECHO BRAVO OSCAR ROMEO. RECEIVED MAYDAY.

In modern procedures, urgency and safety messages can be announced by DSC before the voice message. The DSC category must match the real priority. Move long traffic to a working frequency instead of occupying the distress frequency.

Announcing urgency or safety by DSC, step by step

1. 1Select the call type: All ships for a general announcement, or Individual to a coast station or ship.
2. 2Select the category: Urgency or Safety. It must match the real priority.
3. 3Select the telecommand: telephony, and propose the frequency or channel for the message (Channel 16 or a working channel on VHF; the paired voice frequency or a working frequency on MF/HF).
4. 4Send the DSC announcement.
5. 5Go to that channel or frequency and transmit the PAN-PAN or SÉCURITÉ message by voice. Long safety messages belong on a working channel, not on Channel 16.

Medical transports. A ship or aircraft protected under the Geneva Conventions that carries the sick or wounded announces itself with the urgency signal followed by MAY-DEE-CAL (pronounced as the French médical).

PAN-PAN model: PAN PAN, PAN PAN, PAN PAN. ALL STATIONS, ALL STATIONS, ALL STATIONS. THIS IS ALTAIR, ALTAIR, ALTAIR. POSITION 41 DEGREES 03 MINUTES NORTH, 001 DEGREE 20 MINUTES EAST. NO PROPULSION. NO IMMEDIATE DANGER. REQUIRE TUG ASSISTANCE. 8 PERSONS ON BOARD. DRIFTING SOUTHEAST ONE KNOT. OVER.

SÉCURITÉ model: SÉCURITÉ SÉCURITÉ SÉCURITÉ. ALL STATIONS, ALL STATIONS, ALL STATIONS. THIS IS BOREAL, BOREAL, BOREAL. NAVIGATIONAL HAZARD. SEMI-SUBMERGED CONTAINER OBSERVED IN POSITION 40 DEGREES 55.2 MINUTES NORTH, 001 DEGREE 08.0 MINUTES EAST AT 0940 UTC. VESSELS KEEP SHARP LOOKOUT. OVER.

A false distress alert must be cancelled immediately and traceably. ITU-R M.541-11, reflected in the Radio Regulations after WRC-23, provides a DSC self-cancel where the equipment supports it, followed by a spoken cancellation on the associated distress traffic frequency and a watch to answer any questions.

GMDSS does not end when the alert reaches shore. An RCC/MRCC validates and classifies the information, determines the responsible search and rescue region, coordinates resources and keeps talking to the casualty and the assisting units.

The IAMSAR Manual is the international reference for SAR organization and operations; Volume III is carried by mobile units and is the one relevant to ships taking part. The old term MERSAR, still found in historical syllabuses, has been replaced by IAMSAR.

At the scene, an On-Scene Coordinator (OSC), when designated, coordinates the units. Channel 16 may be used for distress and on-scene traffic, but traffic often moves to suitable working channels; Channel 6 is important for intership and SAR communication, including ship–aircraft.

Ship–aircraft model: RESCUE 15, THIS IS BOREAL. I HAVE YOU IN SIGHT BEARING 220 DEGREES. MY COURSE 270, SPEED 5 KNOTS. DECK CLEAR FOR WINCHING ON THE PORT QUARTER. WIND 300 DEGREES 20 KNOTS. OVER.

When several units respond, the RCC may designate an On-Scene Coordinator (OSC), often the first suitable ship to arrive. The OSC:

A SITREP (situation report) follows a fixed order so the RCC can read it fast:

IAMSAR Volume III describes the standard search patterns a merchant ship may be asked to follow:

When someone on board is ill or injured, ask for advice from a TMAS (Telemedical Maritime Assistance Service) through a coast station, an RCC or a satellite service. Use the urgency priority (PAN-PAN) when the case is very urgent, and escalate to distress only if a life is in grave and imminent danger. Have the facts ready: age, sex, symptoms, vital signs, medication given, the ship's position, ETA at the nearest port and what the medicine chest contains.

Fishing vessels, leisure craft and other non-Convention ships follow national rules, often with a Class D VHF DSC set and a Short Range or Restricted certificate. They use the same priorities, channels and DSC procedures, so a GOC holder must expect alerts from operators with less training: be patient, ask simple questions and repeat key data.

References: ITU-R M.541 · IMO documents relevant to SAR