Distress Signals & Mayday
How to call for help at sea — the Mayday procedure (Rule 31), Pan-Pan and Sécurité formats, visual distress signals, and the Mayday Relay procedure for assisting another vessel.
MAYDAY Call Script
Grave & ImminentUse MAYDAY only when there is grave and imminent danger to the vessel or a person — and immediate assistance is required. Transmit on VHF Channel 16, or SSB 2182 kHz / HF distress frequencies. If you have an EPIRB, activate it.
MAYDAY, MAYDAY, MAYDAY
Say "MAYDAY" three times — this is the distress call.
This is [VESSEL NAME] ×3
State your vessel name three times.
CALL SIGN & MMSI
State your call sign and MMSI once.
POSITION
Give your position: lat/long, or bearing & distance from a known point.
NATURE OF DISTRESS
E.g. "sinking", "fire on board", "medical emergency".
ASSISTANCE REQUIRED
State the type of assistance needed.
PERSONS ON BOARD (POB)
Number of crew and passengers on board.
OTHER INFO & STANDBY
Any injuries, weather, vessel description. Say "STANDBY" and release PTT.
Cancel a Mayday: If the situation is resolved, transmit "MAYDAY, MAYDAY, MAYDAY — this is [VESSEL NAME]. Cancel my Mayday." on VHF 16. Give your vessel name, position, and reason for cancellation.
Pan-Pan & Sécurité Calls
PAN-PAN
Urgency — not immediately life-threateningPAN-PAN, PAN-PAN, PAN-PAN (×3). This is [VESSEL NAME] ×3. [Call sign / MMSI]. Position [lat/long]. Nature of urgency: [describe]. Assistance needed: [describe]. Persons on board: [N]. [Vessel description]. Over.
When to use: Engine failure, medical situation that is serious but not life-threatening, loss of steering, running low on fuel offshore.
SÉCURITÉ
Safety / navigational warningSÉCURITÉ, SÉCURITÉ, SÉCURITÉ (×3). All stations, all stations, all stations. This is [VESSEL NAME] calling. [Warn of navigation hazard: e.g. "submerged object at position..."]. Out.
When to use: Debris in the channel, a vessel not under command, a navigational hazard, or a strong weather warning to broadcast.
Visual Distress Signals
Under COLREG Annex IV, any of these signals may be used to indicate distress and need of assistance. You are not limited to these — anything that draws attention can be a distress signal.
Red parachute rocket flare
Single red star fired into the air — visible up to 40km at night.
Red hand flare
Held aloft, burns red for ~60 seconds. Visible 5–10 nautical miles at night.
Orange smoke (floating or handheld)
Day signal — visible 5–8km from the air on a clear day.
SOS (··· —··· ···)
Morse code SOS by any signalling method — light, sound, or radio.
Square flag + ball (or cone)
Square flag above or below a ball or similar shape on the vessel.
Slowly & repeatedly raising/outstretching arms
Outstretched arms moved slowly up and down — the international arm signal.
Dye marker (orange/yellow)
Coloured dye released into the water — visible from aircraft for up to 1 hour.
EPIRB — 406 MHz
Activate the EPIRB — transmits distress signal to satellites. Include GPS position and registered vessel details.
Water light or strobe
A light attached to a PFD or life raft — flashes to attract attention.
Inverted national flag
Flying your ensign upside down — a recognized distress signal.
Continuous foghorn blast
Continuous sounding of any fog-signalling apparatus.
Guns or explosive signals
Fired at intervals of ~1 minute.
MAYDAY Relay Procedure
Use when you receive a Mayday from another vessel and they cannot reach a shore station, or when an EPIRB alert is sighted but no acknowledgement is heard.
MAYDAY RELAY, MAYDAY RELAY, MAYDAY RELAY
Used when relaying a distress call for another vessel.
This is [YOUR VESSEL NAME] ×3
Identify your vessel.
Received MAYDAY from [DISTRESSED VESSEL]
Name the vessel you are relaying for.
Position & nature of distress
Relay the distressed vessel's position and situation.
POB & assistance required
Relay persons on board and what help they need.
Over
Release PTT — wait for shore station response.
Guidelines Only — Operator Responsibility. Distress procedures are general reference based on COLREGs and ITU radio regulations. VHF channel availability and licensing requirements vary by country. Always carry the appropriate radio operator's certificate and know your local coast guard frequency. The operator is solely responsible for safety of the vessel and crew.