NIMASA GMDSS GOC Exam study plan
NIMASA GMDSS GOC Exam · Give each week a clear focus.
8 weeks · About 7 hours per week
Distress, urgency and safety communications procedures & GMDSS general principles, carriage requirements and functional elements
Map the GMDSS sea areas A1–A4 to the equipment each requires, and state which carriage set applies to a Nigerian-flagged vessel in each area
List the nine GMDSS functional elements and name at least one shipborne installation that satisfies each one
Write out the distress, urgency and safety priority definitions and the correct priority call for each, from memory
Sequence the full DSC distress alert procedure for VHF, MF and HF, including the follow-on radiotelephony distress message and the 5-minute retransmission rule
Your checkpoint
A one-page hand-drawn flowchart of the complete distress alert and distress traffic sequence, checked against the functional element list with no gaps
Distress, urgency and safety communications procedures & VHF and MF/HF radiotelephony including DSC
Distinguish distress relay, distress retransmission and distress acknowledgement, and state who may transmit each
Apply the on-scene communications rules: SRC, on-scene coordinator duties, and the correct use of 156.8 MHz and 2182 kHz
Operate a DSC controller through a simulated distress alert, including cancellation of a false alert on VHF and on MF/HF
State the urgency and safety procedures: PAN PAN and SECURITE formats, medical assistance, and the meaning of MAYDAY RELAY
Your checkpoint
A written false-alert cancellation script for both VHF and MF/HF, plus a 10-step distress scenario walkthrough scored against an answer key you build yourself
VHF and MF/HF radiotelephony including DSC & GMDSS general principles, carriage requirements and functional elements
Explain DSC message structure: format specifier, category, nature of distress, position/time, and the role of the MMSI and group MMSI
Describe the VHF channel plan and the purpose of channels 6, 13, 16, 70 and 75/76
Trace an MF/HF DSC distress alert from transmission through coast station acknowledgement, including the role of the 2187.5 kHz and 8414.5 kHz watch frequencies
Differentiate routine, safety and urgency DSC calling and the correct working-channel handover that follows
Your checkpoint
A completed table of at least 15 DSC fields and VHF channels with their exact purpose, produced without notes
Maritime Safety Information: NAVTEX, SafetyNET and MSI reception & Inmarsat and satellite communication services
Explain NAVTEX: 518 kHz, station identification, message types A–Z, and how to set the receiver to reject unwanted categories
Describe SafetyNET and Enhanced Group Call addressing, including the difference between fixed and variable geographical areas
List the Inmarsat services used in the GMDSS and match each to the sea areas where it is the primary or secondary means
State the sources of MSI and how each is received, including the role of the NAVAREA coordinator
Your checkpoint
A one-page NAVTEX and SafetyNET operator quick-reference card covering frequencies, message-type letters and area addressing
Inmarsat and satellite communication services & Radio propagation, frequencies and basic radio theory
Explain Inmarsat satellite coverage, the function of the LES and the NCS, and how a distress priority call is routed to an RCC
Describe the propagation differences between ground wave, sky wave and line-of-sight VHF, and state which band each governs
Calculate wavelength from frequency and identify the standard marine HF distress and calling frequencies
Explain the effect of the ionosphere, day/night variation and the purpose of HF DSC scanning of multiple frequencies
Your checkpoint
A frequency and propagation worksheet showing wavelength calculations for at least 8 marine frequencies, plus a short written explanation of why HF sky wave is unreliable at night on the higher bands
Emergency position indicating radio beacons and search and rescue radar transponders & Batteries, power supplies, antennas and equipment maintenance/fault finding
Differentiate a 406 MHz EPIRB, a 1.6 GHz EPIRB and a SART, and state the detection and alerting path for each
Describe SART operating principle, range, response on a radar display and correct use during abandonment
Explain battery types, charging regimes and the required capacity tests for GMDSS radio batteries, including the periodic survey requirement
Diagnose common faults: antenna and feeder faults, VSWR problems, no-transmit and no-receive symptoms, and the correct escalation path
Your checkpoint
A fault-finding decision tree covering at least 6 symptoms with the first three checks for each, plus a battery maintenance checklist
Radio regulations, licensing, watchkeeping and interference & VHF and MF/HF radiotelephony including DSC
State the watchkeeping requirements for VHF 16, MF 2182 kHz, and the DSC watch frequencies for each sea area
Explain the station licence, the Ship Radio Licence, the operator certificate requirement and the documents that must be carried
Identify causes of radio interference and the correct reporting and resolution steps, including the role of the administration
State the rules on secrecy of communications, unauthorized transmissions and the prohibition on false distress alerts
Your checkpoint
A regulatory checklist covering licences, certificates and watchkeeping obligations for a vessel in A1 and A2, written from memory and then verified
Distress, urgency and safety communications procedures & GMDSS general principles, carriage requirements and functional elements & Maritime Safety Information: NAVTEX, SafetyNET and MSI reception
Rehearse the full distress, urgency and safety sequence end-to-end under time pressure for VHF, MF/HF and satellite
Re-test the nine functional elements and sea area equipment matrix until recall is instant
Review every previously missed item and convert each into a flashcard with the correct answer
Complete a timed full-length mock examination and score it by domain
Your checkpoint
A scored mock exam result with a per-domain breakdown and a written list of the five weakest areas with a corrective action for each
Milestones
Week 2: Transmit, from memory and without prompts, the complete DSC distress alert and follow-on distress message for a VHF incident, and cancel a false alert correctly
Week 4: Explain NAVTEX message-type coding and SafetyNET area addressing to another person without referring to notes
Week 6: Describe the alerting path and correct use of EPIRB and SART, and pass a self-set battery capacity and fault-finding quiz at 80 percent or better
Week 8: Score 80 percent or higher on a timed full-length mock exam, with no domain below 70 percent