The fourth engineer — also called junior engineer or assistant engineer — is the first officer's rank an engine cadet reaches: the moment you hold your own watch or duty in the engine room. It is also the rank with the hardest first step, because every company wants an engineer with experience and nobody has it at the start. This guide covers the duties, a typical day, the certificate, the courses, the interview and how to get the first contract.
What the fourth engineer does
- Watchkeeping or duty. On manned engine rooms the fourth engineer often keeps the 08:00–12:00 and 20:00–24:00 watch; on UMS ships engineers work by day and the fourth engineer joins the duty rotation once the chief engineer is satisfied.
- Own machinery. Usually a set of auxiliary machines: purifiers, pumps, air compressors, the sewage plant, the fresh water generator, the oily water separator, the incinerator — it depends on the company.
- Maintenance. Work on the main engine and generators together with the second and third engineers; the big overhauls are where a fourth engineer learns the most.
- Records. Soundings, running hours, the planned maintenance entries for own machinery.
- Helping with bunkering and transfers, and with spare parts and stores.
- Safety. Engine-room fire-fighting equipment, rounds, and the engine team's roles in drills.
A typical day
- Manned engine room: 08:00–12:00 and 20:00–24:00 on watch, with maintenance on own machinery outside the watch.
- UMS ship: 08:00–17:00 day work with the second engineer and the crew — often the dirtiest jobs of the day — and, on duty days, the evening round and alarms through the night.
The first weeks are about learning the plant: every pipe, valve and alarm, where the emergency stops are, and how this engine room behaves.
Certificates and documents
- Certificate of competency, officer in charge of an engineering watch (STCW III/1, 750 kW or more) — revalidated every five years.
- Medical certificate — valid for at most two years.
- Basic Training (refreshed every five years), Advanced Fire Fighting, Medical First Aid, PSCRB, Security Awareness / Designated Security Duties.
- ERM; High Voltage where the ship has it; for tankers and gas carriers the basic cargo courses.
- Flag endorsement (STCW I/10) if the ship's flag did not issue your certificate.
What it takes
Under STCW Regulation III/1, you must be at least 18 and have combined workshop skill training and at least 12 months of approved sea service as part of an approved training programme with a training record book — or at least 36 months otherwise, of which at least 30 in the engine department — including at least six months of engine-room watchkeeping under supervision. Then come the exams of your maritime administration.
The first contract
- Stay with the company you were a cadet with. It is the most common way in — they know your work and your training record.
- Accept the plant that is hiring. Bulk carriers and general cargo take juniors more often than tankers and gas carriers.
- Show your cadet time in detail: vessel types, engine makes, the overhauls you took part in, the machinery you looked after.
- Keep every course valid before you apply — a missing course is the most common reason for a fast "no".
- Consider "junior engineer" or "assistant engineer" roles — they count as engine-room experience.
Contracts and rotation
Junior engineers usually sail four to six months, sometimes longer. MLC 2006 limits time on board before repatriation to less than 12 months, and the minimum rest — 10 hours in 24 and 77 in seven days — applies from your first day as an officer.
Interview questions for a fourth engineer
- "How does a purifier work, and what does the gravity disc do?"
- "What do you check on an engine-room round?" Pressures, temperatures, leaks, bilges, levels.
- "What is the limit for the oily water separator?" 15 ppm under MARPOL Annex I.
- "How do you start an air compressor and what protects it?"
- "What do you do when the fire alarm sounds in the engine room?" Your muster duties, the emergency stops, the fixed system.
- "What did you do as a cadet?" Specific machinery and specific jobs.
Common mistakes
- Waiting for the perfect first ship. The first contract is about the experience, not the vessel type.
- A CV that hides the cadet sea time or lists it without machinery.
- Courses that expire mid-contract.
- Paying for a placement. An honest agency is paid by the shipowner.
FAQ
Is the fourth engineer an officer?
Yes — the fourth engineer holds the STCW III/1 certificate and is the junior engineer officer.
What is the difference between fourth engineer and third engineer?
The same certificate; the third has more experience and usually looks after the generators.
How long until promotion to third engineer?
Usually after one or two contracts as fourth engineer.
Can I become an engineer without a maritime academy?
STCW allows the III/1 certificate after 36 months of service without an approved programme — a longer route, through the engine ratings.
Pay and jobs
Fourth engineer is the entry level for engine officers; the step to third engineer usually comes after one or two contracts. Look at the third engineer jobs to see where the path leads, and at engine cadet jobs if you are still before the certificate. Compare ranks on our salaries page.
Your CV
For a junior engineer, the maritime CV matters more than for anyone: it shows the cadet sea service, the machinery and the courses with their dates on one page.
Requirements follow STCW, MARPOL and MLC 2006; your flag state may add its own. Check them with your maritime administration.