🔍 Key Concepts
• GMDSS Sea Areas A1, A2, A3, A4 definitions in SOLAS/ITU documents
• Difference between coverage areas (VHF DSC, MF DSC, Inmarsat) and areas with no reliable coverage
• Geographical limits of Inmarsat A3 coverage (approx. between certain latitudes)
💭 Think About
• For each sea area (A1, A2, A3), recall what type of radio system coverage defines it and think: what is left over when none of those coverages are available?
• Look at which options are describing coverage types and which option is describing a geographic region defined by the absence of A1–A3 coverage.
• Ask yourself: under GMDSS, is there a designated name for the polar or high-latitude regions beyond reliable Inmarsat coverage?
✅ Before You Answer
• Verify the formal definition of Sea Area A3 (it is NOT the entire ocean, but only where certain satellite coverage exists, excluding polar regions).
• Check whether Sea Areas are defined only by Inmarsat footprints or also by VHF/MF coast station coverage – eliminate any option that contradicts this.
• Confirm that SOLAS and GMDSS recognize a specific Sea Area for regions outside A1, A2, and A3 and match that name to one of the choices.