GMA CoC EOOW
GMA Certificate of Competency - Engineer Officer of the Watch (EOOW)
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ExploreAbout this exam
The GMA Certificate of Competency - Engineer Officer of the Watch (EOOW) is a professional marine engineering credential for officers preparing to stand engineering watches in a manned engine room or periodically unmanned machinery space under STCW Regulation III/1. It signals that the holder can run propulsion and auxiliary plant safely, diagnose faults under time pressure, and take charge of the watch. Candidates are typically cadets or ratings with approved seagoing service and workshop skills who have completed an approved education and training programme. Assessment usually combines multiple-choice papers, written theoretical papers and an oral examination with an examiner, so both recall and the ability to reason aloud about plant behaviour matter. The syllabus spans watchkeeping and safe machinery operation, propulsion plant, auxiliary systems, electrical and control engineering, maintenance and materials, ship construction and damage control, maritime legislation including MARPOL and SOLAS, health and safety, and watch administration and human factors. Preparation works best as a structured cycle: master the theory topic by topic, practise numerical work such as power, efficiency and pump calculations, then rehearse spoken explanations of procedures and casualties. Confirm current eligibility, fees and scheduling directly with the GMA, which publishes the authoritative requirements. This page is an independent study resource and is not affiliated with or endorsed by the GMA.
What you'll study
About GMA CoC EOOW preparation
What does the EOOW exam actually consist of?
Expect a mix of multiple-choice papers, written descriptive papers requiring calculations and sketches, and an oral examination. The oral is where examiners probe whether you truly understand systems rather than memorised lists, often by asking you to trace a fault through a circuit or piping arrangement.
How long is the exam and what does it cost?
Timings, fees and the number of papers are set by the GMA and can change between sittings. Check the GMA's official website or your training provider for the current schedule and fee structure rather than relying on second-hand figures.
What is the pass mark and can I retake a failed paper?
Pass standards and retake rules are set by the GMA and published in its current examination guidance. Ask the GMA directly about referral attempts, waiting periods and whether individual papers can be resat. Do not assume a figure quoted by another candidate.
How difficult is the oral examination?
Most candidates find the oral the hardest part because it rewards clear spoken reasoning. Examiners commonly ask you to explain a casualty, such as a loss of lube oil pressure, and justify each action. Practise explaining procedures aloud to a colleague until the sequence and the reasoning behind it are automatic.
In what order should I study the subjects?
Start with watchkeeping and propulsion plant, since these underpin everything else, then move to auxiliary systems and electrical and control topics. Layer in legislation, safety and watch administration nearer the exam, as these are largely recall-based. Keep maintenance and construction running in parallel through short weekly sessions.
What are the most common failure modes?
Candidates typically fail on shallow understanding rather than missing facts: inability to explain why a procedure exists, weak numerical work on power, efficiency or pump calculations, and poor sketching of systems. Skipping legislation and MARPOL because they seem dull is another frequent mistake.
Do I need sea service before sitting the exam?
Approved seagoing service and completed education and training are normally prerequisites under STCW III/1, but the GMA sets the exact amounts and evidence required. Verify your record book and service letters with the GMA well before applying, as incomplete documentation delays sittings.
How should I prepare in the final weeks?
Shift from reading to producing: write timed answers, draw system diagrams from memory and run mock orals with a peer. Review your weak topics daily in short blocks rather than rereading everything. Sleep and rehearsal matter more than last-minute cramming of new material.