🔍 Key Concepts
• GMDSS distress, urgency, and safety priorities on VHF/MF/HF/DSC
• The meaning and use of the URGENT (PAN-PAN) call versus DISTRESS (MAYDAY) and SAFETY (SECURITE) calls
• General rule for what type of traffic may interrupt or override other traffic on the same frequency
💭 Think About
• Think about which type of call is used when there is immediate danger to life, and whether that would be above or below an urgency call in priority.
• Consider the usual order in which radio traffic is cleared on a busy distress frequency: what MUST be cleared first, what comes next, and what can wait?
• Ask yourself what kind of messages are sent as safety calls, and whether they should or should not break into an ongoing urgency exchange.
✅ Before You Answer
• Verify the standard ITU/GMDSS priority order of radio traffic categories (distress, urgency, safety, routine).
• Check the typical voice prowords used: "MAYDAY", "PAN-PAN", and "SECURITE", and how they relate to priority.
• Confirm that routine or ship-to-ship working traffic is handled only after higher‑priority categories are clear.