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Marine VHF cockpit card

MAYDAY, PAN-PAN, SÉCURITÉ, Channel 16, Channel 70, and short message formats.

Grave and imminent danger: raise the alarm now DSC unavailable or not ready, or no time to operate it? Go directly to a voice MAYDAY on Channel 16. Do not delay the call while navigating menus.

Four levels that must not be blurred together

MAYDAY

Distress

A vessel or person is in grave and imminent danger and immediate assistance is required: sinking, fire out of control, collision with serious danger, person overboard not recovered, or a life-threatening medical emergency.

DSC distress alert on 70 if available → voice MAYDAY and distress traffic on 16.

PAN-PAN

Urgency

A very urgent message concerning the safety of a vessel or person, but without grave and imminent danger right now: loss of propulsion drifting toward risk, a serious but currently stable medical problem, or concern for an overdue vessel.

Supported DSC urgency announcement on 70 → brief PAN-PAN announcement on 16 → full message on the nominated working channel.

SÉCURITÉ

Safety

Important navigational or meteorological information: an unlit obstruction, a newly observed hazard, dangerous debris, or a local warning that other vessels need promptly.

Individual DSC safety call to a coast station → its assigned working channel; or, for an appropriate all-ships warning, a brief announcement on 16 → working channel.

ROUTINE

Normal communication

Calling another vessel, marina, harbour, coast station, pilot, or service when there is no distress, urgency, or safety broadcast.

Individual DSC routine call on 70, a published local calling channel, or a very brief call on 16 → voice conversation on a permitted working channel.

Channel 16, Channel 70, and working channels

VHF 16 · 156.800 MHz

Priority voice and brief calling

Use Channel 16 for voice distress, urgency, very brief safety communication, and initial calling when another permitted method is unavailable. Keep listening when required and practical, and immediately protect any distress traffic.

Do not hold routine conversations, make radio checks, or give long non-distress explanations on 16.

DSC 70 · 156.525 MHz

Digital alerts and selective calling

Channel 70 is reserved for Digital Selective Calling. A DSC packet can carry MMSI, priority, a requested voice channel and, for distress, position when the radio has current GNSS data.

No voice is transmitted on 70—not conversation, a radio check, or even the spoken word MAYDAY.

Working channel

The actual voice conversation

Move routine calls and longer urgency or safety messages to a permitted ship-to-ship, port, VTS, or coast-station channel selected for that service and location.

There is no universal working channel for every place and purpose. Use the current local channel plan or the channel assigned by the station.

Voice MAYDAY on Channel 16

  1. MAYDAY · MAYDAY · MAYDAY
  2. THIS IS · [vessel name ×3] · [call sign] · [MMSI]
  3. MAYDAY · THIS IS [vessel name, call sign, MMSI]
  4. MY POSITION IS [latitude/longitude, or bearing and distance from a known point]
  5. [nature of distress and immediate danger]
  6. I REQUIRE [specific assistance]
  7. [number of people aboard; injuries or people in the water]
  8. [vessel description, survival equipment, intentions, other useful facts]
  9. OVER

Stay on Channel 16 and keep the radio available. Repeat the call if no reply is received after a reasonable interval, update the rescue authority if the situation or position changes, and follow its instructions.

PAN-PAN and SÉCURITÉ: announce first, then move the detail

PAN-PAN — Urgency concerning a vessel or person

PAN-PAN · PAN-PAN · PAN-PAN ALL STATIONS · ALL STATIONS · ALL STATIONS THIS IS [vessel name ×3, call sign, MMSI] PLEASE GO TO CHANNEL [working channel] OUT

On the working channel, repeat PAN-PAN and identification, then give the full urgent message. If the danger becomes grave and imminent, upgrade immediately to MAYDAY.

SÉCURITÉ — Navigational or weather safety information

SÉCURITÉ · SÉCURITÉ · SÉCURITÉ ALL STATIONS · ALL STATIONS · ALL STATIONS THIS IS [vessel or station identification] SAFETY MESSAGE ON CHANNEL [working channel] OUT

The safety message should identify the hazard, its precise position, time observed, movement if any, and the area or vessels affected.

Learning aid only — not for navigation. Confirm current rules and local requirements with the relevant authority.

Free forever. No tracking, no signup.

A learning aid — not for navigation. Rule text is reproduced from the public-domain USCG Navigation Rules. Chart symbols follow NOAA U.S. Chart No. 1. All diagrams and questions are our own. Not affiliated with or endorsed by the RYA, ASA, NASBLA, IMO, or any licensing authority.

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Core content reviewed: July 15, 2026