Sea Areas and Carriage Requirements
What the exam tests here
This domain tests SOLAS Chapter IV: who must comply, and which radio equipment a given ship must carry for the sea areas she trades in. Accuracy on tonnage thresholds and on conditional items (NAVTEX, EGC) is what separates a pass from a fail.
Who is bound
SOLAS IV applies to all passenger ships and cargo ships of 300 GT and above on international voyages. Cargo ships below 300 GT and non-SOLAS craft follow national rules, but the equipment logic is the same.
Carriage logic by sea area
- A1: VHF installation with DSC capable of distress alerting from the position from which the ship is normally navigated, plus a VHF DSC watch on Ch70; 406 MHz float-free EPIRB; 9 GHz SART (2 on cargo ships of 500 GT and above, 1 on 300-500 GT); NAVTEX receiver where an international NAVTEX service is provided; two-way VHF radiotelephone sets for survival craft (3 on cargo ships of 500 GT and above, 2 on 300-500 GT); reserve source of energy.
- A2: the A1 items plus an MF installation with DSC and radiotelephony on 2182 kHz, and MF DSC watch on 2187.5 kHz.
- A3: an Inmarsat installation capable of distress alerting and EGC (SafetyNET), or an MF/HF installation with DSC and NBDP, plus EGC where NAVTEX or HF MSI does not cover the area.
- A4: MF/HF with DSC and NBDP, in addition to the A1-A3 items.
Worked example
An 8,000 GT bulk carrier trades worldwide. She needs VHF DSC, MF/HF with DSC and NBDP on all distress bands, an Inmarsat-C terminal with EGC, NAVTEX, one float-free EPIRB, two 9 GHz SARTs, three two-way VHF sets and a reserve battery capable of running the installation.
Traps
- Carrying NAVTEX automatically "because everyone does" - it is required only where the service exists.
- Assuming Inmarsat-C removes the need for EGC; the EGC receiver must cover the operating area.
- Quoting the wrong tonnage threshold (300 GT, not 500 GT, is the SOLAS entry point).