Module 8 - Digital Selective Calling
Distress Alert Reception And Acknowledgement
When a VHF DSC distress alert sounds, immediately cease any transmission that may interfere with distress traffic and continue a listening watch on Channel 16. Read the received message without delaying the watch: note the distressed identity, category, position and UTC shown by the set, then listen for the voice Mayday and coast-station coordination.
The MCA small-craft procedure says that if there is no DSC acknowledgement after five minutes, a vessel able to offer assistance may acknowledge by voice on Channel 16. Do not send an impulsive digital distress acknowledgement from a small-craft set or crowd the first moments with repeated calls while a coast station may be responding.
A useful voice acknowledgement identifies the casualty, identifies your vessel and states what assistance you can give, including ETA if proceeding. If the distress has not reached an appropriate coast station, use any available means to relay it. Safety of your own vessel and crew still governs what assistance is possible.
Optional quick check
Section 5 of 9
A DSC distress alert is received but no acknowledgement has yet been heard. What should a small craft do first?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
Continue studying Digital Selective Calling
This public lesson is part of Revision Module 8. Full revision access adds the guided Learn, Practise and Test flow, flashcards and revision progress.