Pass your AB, QMED, OS, or EDH exam with a question bank mapped to the actual NMC and MCA syllabi.

Merchant Mariner Ratings Exams

Ratings exams certify the unlicensed workforce that keeps the merchant fleet running: the Able Seamen who stand lookout watches and handle mooring lines, the QMEDs who watch the engine-room gauges and maintain auxiliaries, the Ordinary Seamen learning the trade, and the deck and engine-department specialists whose endorsements determine which jobs they can sign on for. These exams are less famous than the officer licenses but are no less consequential for the mariners who sit them, because an AB Unlimited card opens the door to every US-flag deep-sea berth while an OS card keeps you in entry-level deck work. MMCE.app builds a dedicated study track for every major rating endorsement and treats the unlicensed half of the merchant fleet as a first-class audience, not an afterthought.

Exam systems by country

United States (USCG, NMC). The National Maritime Center administers closed-book multiple-choice exams. Able Seaman tiers include AB Unlimited (Any Waters, Unlimited), AB Limited (vessels over 500 GRT on oceans or 200 GRT coastwise), AB Special (over 100 GRT), AB OSV (Offshore Supply Vessels), and AB Sail. QMED (Qualified Member of the Engine Department) endorsements include Oiler, Fireman/Watertender, Junior Engineer, Electrician, Refrigerating Engineer, Machinist, Pumpman, and Deck Engineer. Wiper and Ordinary Seaman are entry-level ratings that require minimal testing. Lifeboatman is a near-universal endorsement that every deck rating pursues early. Tankerman PIC and Tankerman Assistant are also rating-level credentials and open access to the US tank-vessel fleet.

United Kingdom (MCA). Efficient Deck Hand (EDH) is the UK equivalent of the US AB. Candidates complete an approved course and practical assessment plus a written theory exam covering seamanship, steering, and lookout duties. MCA also issues Able Seafarer Deck and Able Seafarer Engine certificates to STCW Regulation II/5 and III/5 standards. The RFPNW (Rating Forming Part of a Navigational Watch) is the STCW baseline below Able Seafarer Deck.

Canada (Transport Canada). Bridge Watch Rating and Engine Room Rating certificates align with STCW and are issued after approved sea service plus written exams. TC also issues a Chief Cook certificate and several domestic fishing-vessel ratings.

Australia and New Zealand (AMSA, MNZ). Integrated Rating, Marine Engine Driver, and General Purpose Hand certificates align with STCW and cover both deck and engine duties for the smaller vessels that dominate Australian coastal trade.

Philippines, India, and most STCW nations. Able Seafarer Deck / Engine and Rating Forming Part of a Navigational Watch (RFPNW) or Engineering Watch (RFPEW) certificates are issued under STCW Reg II/4, II/5, III/4, and III/5. The Philippines produces the largest global ratings population.

Typical exam structure

AB Unlimited (USCG): a single module of 70 questions covering deck seamanship, cargo, safety, and rules of the road integrated into the seamanship questions. Time limit 3 hours 30 minutes. Pass 70% overall; rules-of-the-road questions inside the module are tracked separately and require 90%.

QMED endorsements (USCG): one General Subjects module of 120 questions plus an endorsement-specific module of 40 to 70 questions (Oiler, Electrician, etc.). Time limits scale with question count. Pass 70%. A QMED can stack multiple endorsements on the same card by sitting only the endorsement-specific modules for each additional trade.

Lifeboatman (USCG): 70 questions plus a practical demonstration of lifeboat handling at an approved facility including boat launch, recovery, engine start, and survival-craft command.

MCA EDH: a 90-minute written paper plus a practical assessment of knots, splices, heaving line, and steering.

Typical sea service / prerequisites

USCG AB Unlimited: 1,080 days of deck service on ocean or near-coastal routes. AB Limited: 540 days. AB Special: 180 days. AB OSV: 180 days on OSVs. Ordinary Seaman: no sea service, just a TWIC and a USCG medical. QMED: 180 days of engine-department service plus completion of an approved course for Electrician, Junior Engineer, or Refrigerating Engineer. Lifeboatman: 6 months of deck service. MCA EDH: 12 months sea service as a trainee plus approved course.

Every rating candidate in the US must hold a valid TWIC, an unexpired USCG medical certificate, and STCW Basic Training (Personal Survival Techniques, Basic Fire Fighting, Elementary First Aid, Personal Safety and Social Responsibility). Fit-for-duty and drug testing requirements apply to hiring but not to the exam itself.

Core subject matter

Deck ratings (AB, OS, EDH). Knots, bends, and hitches; wire and fiber line care; splicing; mooring operations including line handling and the dynamics of running lines under load; anchor work and ground tackle; cargo gear (booms, cranes, hatch covers); lifesaving equipment per SOLAS Chapter III and the LSA Code (lifeboats, liferafts, immersion suits, EPIRB, SART); fire fighting equipment and shipboard firefighting organization; watchkeeping duties under STCW Reg VIII; steering orders and helm commands; lookout duties; IALA-B buoyage for US-focused exams and IALA-A for UK and most of the rest of the world; weather and sea state; the basics of COLREGS lights, shapes, and sound signals; basic shipboard safety including enclosed space entry and hot work permits.

Engine ratings (QMED, Wiper, Engine Room Rating). Marine diesel engine fundamentals (two-stroke and four-stroke, scavenging, turbocharging); auxiliary machinery (centrifugal and positive-displacement pumps, air compressors, purifiers, boilers, evaporators, refrigeration); fuel and lube oil systems including purifier operation and fuel changeover procedures for ECA zones; electrical fundamentals for the QMED Electrician (AC and DC distribution, generator paralleling, insulation resistance testing, switchboard operations); bilge and ballast systems; oily water separators and MARPOL Annex I compliance; watchkeeping duties in a manned engine room and UMS (unattended machinery space) alarm response; tag-out and lockout procedures.

Common pitfalls

Candidates underestimate the seamanship depth of the AB exam and assume it is a "deckhand" test. In fact the NMC question bank demands precise knowledge of specific gear (names of blocks, parts of an anchor, parts of a cargo hook) and specific regulations (which SOLAS chapter governs lifesaving, what 46 CFR Subchapter I covers). QMED candidates often fail because they prepare only for their specific endorsement and neglect the 120-question General Subjects module, which is the larger of the two and covers the full engine room. Lifeboatman candidates fail the practical, not the written, because they have never actually lowered a boat. MCA EDH candidates fail the practical knot and splice assessment because they have practiced on rope but never on the specific 24mm and 32mm line used in the test.

How to study with MMCE.app

Select your target rating (AB Unlimited, QMED Oiler, EDH, etc.) at onboarding. The adaptive quiz engine surfaces questions from the appropriate NMC or MCA syllabus and tracks your ability module-by-module. The spaced-repetition flashcard system drills knot names, line types, parts of shipboard equipment, and the short definitions that dominate rating exams. Full-length practice exams simulate NMC timing. The AI tutor explains every answer with citations to 46 CFR, SOLAS, STCW, and MARPOL so you learn the "why" and not just the answer. A readiness score tracks your probability of passing and the platform surfaces weak areas you might otherwise skip.

Related credentials on MMCE.app

Officer exams (Third Mate, QMED to Third Assistant Engineer) sit above ratings on the career ladder and are fully supported. Specialty endorsements add-ons include Tankerman PIC (common for AB Tankerman positions), Lifeboatman (required for most ratings), Advanced Firefighting, and Radar Observer (rarely held by ratings but sometimes pursued by bridge watch ratings moving toward a license). The conventions hub covers the COLREGS, SOLAS, and MARPOL content embedded in every ratings exam. Many naval enlisted sailors leaving active duty use their sea time to credit toward the AB Unlimited and QMED exams; the naval hub describes that transition.