Sound signals
Sound signals for manoeuvring, restricted visibility and distress. Based on COLREGS Rules 34 and 35.
Related reference
Signal key
● = short blast (~1 second) — = long blast (4–6 seconds)
| Signal | Meaning | Context |
|---|
Key fog signal rules
- Vessel underway under power: one long blast every 2 minutes
- Sailing vessel underway: long-short-short every 2 minutes
- Vessel at anchor: bell rapidly for 5 seconds every minute
Distress signals
Internationally recognised distress signals include: Mayday on VHF 16, DSC distress on channel 70, SOS in Morse, orange smoke, red flares, continuous fog horn, EPIRB activation, and slowly raising and lowering outstretched arms.
Flares have expiry dates — check and replace regularly.