A real route into the Merchant Marine. Ordinary Seafarer (OS) and Wiper are entry-level endorsements without a professional examination or qualifying sea-service requirement. AB and QMED are skilled national ratings, not officer licenses. Medical, drug-testing, application, security and employer requirements still apply. NMC entry-level checklist.
Able Seafarer (AB): deck skills and two written subjects
Formerly called Able Seaman. Q450 Navigation and Rules of the Road and Q451 Deck General and Safety are the two AB01 written modules. The NMC-linked examination guide lists 50 questions and a 70% passing score for each. These are official examination-format figures, not the length of your custom Mariner practice test.
- Q450: nautical terms, compass basics, vessel lights and shapes, sound signals, aids to navigation and launching-device operation.
- Q451: knots and seamanship, deck machinery and ground tackle, anchoring and emergency towing, pollution prevention, person-overboard response, firefighting, lifesaving equipment and survivor care.
- Separate AB02 practical: the linked guide specifies one of two splices in 15 minutes, plus four required and six additional knots, bends or hitches in a separate 15 minutes. The four required are square knot, clove hitch, sheet bend and French bowline. Reading or answering a diagram question is not a substitute for making the knots.
- Lifesaving qualification: national AB applicants must qualify as Lifeboat Operator or Lifeboat Operator-Limited, as appropriate. The practical, approved-course and vessel-specific pathways are separate from Q450/Q451.
- Exam-room reference: the current Q450 sample dated August 27, 2026 expressly permits only The American Practical Navigator (Bowditch), Volume II. Do not assume a Navigation Rules book is allowed. Check the current NMC examination instructions.
Service is category-specific. Unlimited, Limited, Special, OSV, Sail and Fishing Industry are the six categories in 46 CFR 12.401. The active NMC checklist applies temporary service figures only to applications processed December 22, 2023 through December 22, 2026: 540 days Unlimited, 360 Limited, 180 Special/OSV/Sail/Fishing. These are not timeless rules; course credit and the NMC evaluation control. AB-MODU is separately listed on the checklist with a Marine Safety Manual basis, not a seventh category in §12.401.
National AB is not automatically STCW Able Seafarer-Deck. Seagoing service may require RFPNW, Basic Training, competency assessments and the appropriate survival-craft qualification. Able Seafarer-Deck normally requires 18 months of deck service while RFPNW-qualified, or 12 months with approved training; §12.603 and applicable crossover provisions control.
NMC AB checklist · National AB requirements · Category service rules · Written and practical requirements · STCW Able Seafarer-Deck · Lifeboat Operator checklist
QMED: choose a rating, not an invented rank ladder
Qualified Member of the Engine Department is a skilled rating below officer. Five rating qualifications are available. Junior Engineer is not designated the “highest” QMED rating. QMED – Any Rating means qualifying for all five, not a sixth exam or automatic credit for the others.
- Junior Engineer: Q800 + Q801, two written modules.
- Electrician / Refrigerating Engineer: Q802 + Q803, two written modules.
- Oiler: Q804 + Q805, two written modules.
- Boiler Technician / Watertender: Q806, one written module.
- Pump Technician / Machinist: Q807 + Q808, two written modules.
The NMC-linked guide lists 70 questions and 70% per QMED module. Q806 is one module, not Parts I and II. “Fireman/Watertender” and “Pumpman/Machinist” remain older exam-title aliases for today's Boiler Technician/Watertender and Pump Technician/Machinist.
- Study the plant and the safe work: watchkeeping, boilers and steam, diesel engines, pumps, piping, auxiliary machinery, lubrication, maintenance, tools, electricity and refrigeration as applicable to your selected rating.
- Safety is integrated: first aid, fire prevention and firefighting, communications, emergency equipment, pollution prevention, damage control and hazardous materials belong inside the rating exams. Do not add an engineer-officer safety exam as a universal QMED requirement.
- Qualifying credit: the guide allows Junior Engineer without Q800/Q801 testing after successful Electrician/Refrigerating Engineer, Oiler and Boiler Technician/Watertender examinations, with other requirements met. Approved courses and existing-holder additions have separate conditions; match your NMC ATT.
- National service: normally six months in a rating at least equal to Wiper or Coal Passer. Approved school-ship or training alternatives exist; age 18, medical, drug-testing, English and examination requirements also apply.
STCW Able Seafarer-Engine is separate. Meet RFPEW requirements before accumulating the relevant AS-E service: normally 12 months, or six months plus approved training, with Table A-III/5 competence and Basic Training. National QMED alone does not automatically issue AS-E. Lifeboat Operator/Proficiency in Survival Craft may be required by a particular role or vessel, but is not a universal AS-E prerequisite. Relevant rules are §12.607 (AS-E) and §12.609 (RFPEW), not §12.605 (RFPNW).
NMC QMED checklist · Five national QMED ratings · Service and training · Examination subject matrix · STCW Able Seafarer-Engine · RFPEW
Practice wisely: samples are not the whole examination bank
Mariner retains the current sample sets: 50 source occurrences each for Q450/Q451, and 70 each for Q800–Q808. The October 14 release verified 98 ready AB occurrences and 611 ready QMED occurrences; the unchanged exact-duplicate rule yielded 506 combined QMED practice entries. These dated coverage figures do not establish a complete national question bank. Ready counts can vary by selection and later separately approved publications. Archived Engine/Deck practice is broader material, not a fully mapped QMED/AB-only archive.
Plan for the missing experience: use the NMC subject outlines as your checklist, learn practical skills hands-on, study applicable training material and take approved courses where needed. Similar engineering or safety concepts may overlap with officer study; no “zero question overlap” claim is made.
Official sample PDFs for your study plan
Junior Engineer Q800 and Oiler Q804 emphasize plant and auxiliary systems; Q801 and Q805 also cover electrical, tools, maintenance and safety topics. These broad guides are not fixed subtopic question weights. Use the official module outlines. NMC examination-room materials and module-specific instructions, not a study app, decide allowed books and references. NMC examination-room materials.
Drawings: open the official source, keep your place here
For exactly matched figures, Study mode can open the USCG-hosted PDF at the drawing's page in a separate tab. Phone viewers may ignore the page target, so the figure ID and page number are shown. The official samples also include answers: reference links are not presented as an answer aid during examination-style testing. Mariner does not copy, crop or frame reproduction-restricted plates. Original teaching diagrams require independent authorship and technical alignment, not tracing a copyrighted picture.
Source review: October 15, 2026. NMC's index was refreshed September 2026; its still-linked administration guide is the August 2014 edition. Current sample dates and current CFR/checklists are distinguished from that older guide. This is independent study guidance, not USCG approval, credential eligibility or a guarantee of passing. Your current NMC evaluation and Approved to Test letter control.
Official module outlines and sample examinations · NMC examination guide (2014 edition) · Copyright Office: government works and reproduction rights