Appendix III
GMDSS Equipment for Sea Areas
AI, A2, A3 and A4
GMDSS AMENDMENTS TO THE SOLAS CONVENTION require that all
passenger vessels and cargo vessels of 300 G RT and over, on international
voyages, must fit a range of equipment according to their G MOSS Sea
Area of Operation. The main criteria that will dictate the type/number
of units carried are:- Ships must be able to send Distress Alerts by two independent means
(i.e. two different types of service) for each GMDSS Sea Area of
Operation that they expect to visit.
Distress Alerts must be able to be sent from the position from which
the vessel is normally navigated (bridge/wheelhouse).
Availability of equipment must be assured by: - Duplication of equipment.
Carrying a person qualified to maintain and repair GMDSS
equipment and/or - A contract for shore-based maintenance.
For vessels remaining within Sea Area A 11 A2 the only choice is
between manufacturers - there is no choice between types of equipment.
Vessels moving out of Sea Area A2 and into Sea Area A3 must fit
additional equipment to that carried for Sea Area Al and A2 and can,
theoretically, choose between Marine HF SSB Radio with DSC, and
Inmarsat satellite communications equipment.
In practical terms, if you have fitted Marine MF SSB Radio with
DSC for Sea Area A2, your equipment will probably cover the HF bands
- and therefore cover you for Sea Area A3 and A4 operation. And - if
you are operating outside of NAVTEX coverage (which is true in some
A1IA2 areas and will be the case in most A3/A4 areas) and have fitted
Inmarsat-C to receive the SafetyNET service - your Inmarsat-C will
also provide Distress AJerting/Messaging facilities acceptable for GMDSS
purposes (up to and including Sea Area 3).
For Sea Area A3, therefore, the reality is that most vessels will carry
MF /HF SSB with DSC and also Inmarsat-C - both of which can provide
Distress Alerting and messaging facilities that meet GMDSS requirements
(and, incidentally, provides for 'two different services' for Distress Alerts,
both of which can be fitted to operate from the bridge/wheelhouse).
224 THE NAUTICAL INSTITUTE