- What You Are Actually Preparing For
- The Five Preparation Groups at a Glance
- Why Your Approval to Test Controls Everything
- Group 1: Rules of the Road (Q100 or Q300)
- Group 2: Deck General (Q347)
- Group 3: Deck Safety (Q348)
- Group 4: Navigation General (Q349)
- Group 5: Chart Plot (Q350)
- Where Q352 Fits and Where It Does Not
- Sequencing Your Weeks Around the Weak Spots
- Sources and Staying Current
- Frequently Asked Questions
- NM1GI here means National Master 100 GL and Inland, administered by the U.S. Coast Guard National Maritime Center.
- Prepare across five route-aware groups: Rules, Deck General, Deck Safety, Navigation General, and Chart Plot.
- Your individual approval to test, not a generic checklist, decides which modules and route you actually sit.
- Q352 is a separate raise-of-grade module, not a sixth group for every original-issue candidate.
What You Are Actually Preparing For
National Master 100 GL and Inland (NM1GI) is a mariner credential pathway administered by the United States Coast Guard National Maritime Center (NMC). The examination reference is GLI06, Master or Mate less than 100 GRT, and the Master identity is the one this guide retains throughout. If you want the full definition before going deeper, start with What Is NM1GI? and then return here.
The first thing to understand is that this is not a single, uniform, one-size-fits-all test. The NMC publishes a catalog of modules, and the modules you are assigned depend on your route and your individual approval to test. That means a study plan built from a generic "Coast Guard exam" template can send you down the wrong path. A good plan starts from the module list, then maps it to your approval.
This guide treats the exam as five unweighted preparation groups. The NMC does not publish percentage weights for these groups in the sources used here, so you will not find a "spend 30 percent of your time on X" formula below. Instead, the guide shows what each group covers and where candidates commonly need more time. For a deeper breakdown of the groups themselves, see NM1GI Exam Domains: Complete Guide to All 5 Content Areas.
The Five Preparation Groups at a Glance
Use the table below as your orientation map. The module codes come directly from the NMC catalog.
| Group | Module | Core Subject Matter |
|---|---|---|
| 1 | Rules of the Road: International and Inland (Q100) OR Inland (Q300) | Watchkeeping, COLREGS, Inland Navigational Rules |
| 2 | Deck General (Q347) | Seamanship, vessel handling, anchoring, maritime law, shipboard management |
| 3 | Deck Safety (Q348) | Stability, firefighting, emergency procedures, communications and signals |
| 4 | Navigation General: Great Lakes and Inland (Q349) | Piloting, compass, aids to navigation, weather, tides and currents |
| 5 | Navigation Problems: Chart Plot (Q350) | Chart-based plotting problems: fixes, bearings, distance off, dead reckoning |
Notice that Group 1 is a choice, not an addition. You study either the International and Inland Rules module (Q100) or the Inland-only module (Q300), according to your approved route. Counting that choice once is what keeps the total at five groups rather than six.
Why Your Approval to Test Controls Everything
Several consequences follow from this, and they are the most commonly misunderstood part of preparation:
- Route matters. Great Lakes-and-Inland versus Inland-only applicability changes which Rules module you take and which seamanship topics are in play.
- Credit matters. If your approval grants credit for any module, you should not spend weeks re-studying it, and you should confirm that in writing before you plan.
- Currency matters. The examination guide referenced here reflects regulations effective 2014-03-24. It is a useful content reference, but it is not a new 2026 universal exam specification. Always pair it with the current published NMC module-topic index.
Eligibility and sea-service questions sit upstream of all this. If you have not yet confirmed that you qualify, read NM1GI Requirements: Eligibility, Prerequisites & How to Qualify first, because there is no point optimizing a study schedule for an exam you have not been approved to take. For fee mechanics, see NM1GI Certification Cost: Complete Pricing Breakdown.
Group 1: Rules of the Road (Q100 or Q300)
The Rules module is where many candidates feel most confident and where precision errors quietly cost the most. The published topic list for this group is Watchkeeping, COLREGS, and the Inland Navigational Rules. Which of those you are tested on depends on whether you are assigned Q100 (International and Inland) or Q300 (Inland).
Rules of the Road: International and Inland (Q100) OR Inland (Q300)
This is a route-selected module. Confirm which one your approval assigns before you buy or download any study material.
- Know the difference between the International (COLREGS) and Inland rule sets, because the two diverge in meaningful ways.
- Practice applying right-of-way logic to described situations, not just reciting rule numbers.
- Review watchkeeping principles as they relate to lookout and safe navigation.
- Drill sound signals, lights, and shapes until you can identify them from a short description.
A common trap is studying both rule sets with equal intensity when only one is assigned. If your route is Inland-only, depth in the Inland Navigational Rules pays off more than breadth across International-only provisions. If your approval assigns Q100, you need to be fluent in how the two regimes differ and when each applies.
Group 2: Deck General (Q347)
Deck General is the broadest module in the catalog, and it is the one most likely to reward hands-on experience. It spans seamanship, vessel handling, maritime law, and shipboard management. Treat it as several smaller subjects rather than one large block.
Seamanship and Vessel Handling
This cluster covers the practical side of operating a vessel.
- Marlinspike seamanship and purchases, blocks, and tackle
- Vessel maneuvering and handling, including rivers and estuaries and shallow water
- Interaction with a bank or passing ship
- Berthing and unberthing, anchoring and mooring
- Dragging anchors and clearing fouled anchors
- Turn circle, pivot point, advance and transfer, and wake reduction
Law, Credentialing, and Shipboard Management
This cluster is more reading-intensive and rewards careful memorization of what is required and when.
- Maritime law and national maritime law
- Credentialing of seamen
- Shipboard management and training, ship sanitation, and vessel alteration, repair, or hot work
- Safety, ship's business, and certificates and documents required
Candidates who work daily on the water often find the handling topics intuitive and the law and documentation topics tedious. That asymmetry is worth planning around, and it is covered in the sequencing section below. For a realistic read on where candidates struggle, see How Hard Is the NM1GI Exam? Complete Difficulty Guide.
Group 3: Deck Safety (Q348)
Deck Safety combines technical knowledge (stability, construction, firefighting) with procedural knowledge (emergencies, signals). It is the module where "what do you do first" thinking matters most.
Stability, Construction, and Damage Control
Expect to understand principles, not just definitions.
- Principles of vessel construction
- Trim and stability
- Small engine operations and maintenance within the vessel power plants topic
Fire Prevention and Firefighting
This is a well-defined cluster that rewards systematic review.
- Organization of fire drills
- Classes and chemistry of fire
- Firefighting systems and appliances
- Basic firefighting and prevention
Emergency Procedures and Communications
Learn the sequence of actions for each scenario, because questions tend to test priorities.
- Collision, temporary repairs, and fire or explosion
- Abandon ship procedures and passenger and crew safety in emergencies
- Rescuing survivors from a ship or aircraft in distress
- Man overboard procedures and emergency towing
- Signals: storm, wreck, distress, and special
The module list also includes Watchkeeping and Basic Principles, Watchkeeping under Deck Safety, so do not assume watchkeeping is covered only in the Rules module. Both appear in the published catalog.
Group 4: Navigation General (Q349)
Navigation General: Great Lakes and Inland is the knowledge side of navigation. It is distinct from the chart-plot module that follows, even though the topic names overlap. Here the focus is on understanding concepts, instruments, and publications.
Position Determination and Piloting
- Piloting, distance off, bearing problems, and fix or running fix
- Chart navigation and dead reckoning
- Electronic navigation, instruments, and accessories
Aids, Charts, and Publications
- Aids to navigation
- Charts, navigation publications, and Notices to Mariners
Compass Work
- Principles of the magnetic compass
- Magnetic compass error and correction
- Determination of compass error, including terrestrial observation
- Magnetic and gyro compass distinctions
Meteorology, Oceanography, Tides, and Currents
- Characteristics of weather systems
- Weather charts and reports
- Tides and tidal currents
Compass error is the single area where conceptual understanding and arithmetic meet. Candidates who memorize a mnemonic without understanding what error and variation represent tend to stumble when a problem is phrased differently from the practice version.
Group 5: Chart Plot (Q350)
Navigation Problems: Chart Plot is the practical, work-the-problem module. The NMC catalog lists the same family of topics as Q349 (piloting, distance off, bearing problems, fix or running fix, chart navigation, dead reckoning, electronic navigation, instruments, aids to navigation, and charts and publications), but here you apply them on a chart with plotting tools.
Practical advice that applies specifically to chart plotting:
- Work problems with the same tools you will have available on test day.
- Label every line, time, and course on the chart as you go, so errors are traceable.
- Practice running fixes and distance-off problems until the procedure is automatic.
- Check your plotted position against a quick dead-reckoning sanity estimate before committing.
If you want a condensed refresher on the formulas and procedures you will repeat most, the NM1GI Cheat Sheet: One-Page Review of Must-Know Facts is a useful companion. And to rehearse under realistic conditions, the NM1GI practice test site lets you test yourself on the knowledge-based groups.
Where Q352 Fits and Where It Does Not
Q352, Navigation and Deck General/Safety, is a separately listed raise-of-grade route module. It is not a universal sixth exam group appended to every candidate's plan, and it is not a second Rules subject. If your approval to test assigns Q352 as part of a raise-of-grade route, then it belongs in your preparation. If you are on a full original route, it does not.
Key Takeaway
Do not add Q352 to your study plan unless your approval to test lists it. Adding unassigned modules wastes weeks, while omitting an assigned one risks a retake. The approval letter, read carefully, is the single most useful planning document you have.
Sequencing Your Weeks Around the Weak Spots
This is the one place for general study method, and it is tied directly to the five groups. The logic is simple: put skill-based work early and repeat it, put fact-heavy work in the middle, and use the final stretch for integrated review.
Chart Plot (Q350) and Navigation fundamentals
- Start plotting problems immediately, since this skill builds slowly.
- Pair each plotting session with the matching Q349 concept, such as compass error or dead reckoning.
Rules of the Road (Q100 or Q300) and Deck Safety (Q348)
- Confirm your assigned Rules module first, then drill lights, shapes, and right-of-way scenarios.
- Work through firefighting, emergencies, and stability in procedure order.
Deck General (Q347) and Navigation General (Q349)
- Cover the law, credentialing, and documentation cluster deliberately, since it is easy to neglect.
- Add meteorology, tides, and publications, then keep plotting in weekly rotation.
Integrated review
- Take timed practice sets across all assigned groups.
- Revisit whichever group your practice results show as weakest.
Adjust the length to your own schedule and prior experience; this is a template, not a mandate. Pass-rate and scoring questions come up constantly at this stage, so for context read NM1GI Pass Rate: What the Data Shows and NM1GI Passing Score: Exactly What You Need to Pass. For the scheduling side, see NM1GI Exam Dates: Testing Windows, Deadlines & Scheduling.
Sources and Staying Current
Because the published guide reflects regulations effective 2014-03-24, a disciplined candidate verifies content against current NMC material. The sources used for this article are the NMC pages for the GLI06 route and the Q352 module, along with the NMC examination guide for deck and engineering exams. Cross-check them against your approval to test before you finalize your plan.
- The GLI06 route page for Master or Mate less than 100 GRT (Q100-Q352) on the Coast Guard NMC site
- The NMC deck and engineering examination guide as of 3-24-14
- The NMC Q352 Navigation and Deck General/Safety document
Once you have passed, the practical question becomes what the credential does for your career. See NM1GI Jobs for who hires, and Is the NM1GI Certification Worth It? Complete ROI Analysis if you are still weighing the investment.
Frequently Asked Questions
Plan around five route-aware preparation groups: Rules (Q100 or Q300), Deck General (Q347), Deck Safety (Q348), Navigation General (Q349), and Chart Plot (Q350). Your individual approval to test determines which modules you are actually assigned, so confirm that before finalizing your plan.
No. The Rules module is one choice according to your approved route: Q100 covers International and Inland, while Q300 covers Inland only. Study the one your approval assigns rather than splitting your time across both.
No. Q352 is a separately listed raise-of-grade route module covering Navigation and Deck General/Safety. It applies only if your approval to test assigns it, and it should not be treated as a sixth group for a full original route.
That depends on your route. The NMC table marks heavy-weather handling and launching of lifeboats and liferafts in heavy weather as Great Lakes-specific. If your approval is Inland-only, confirm applicability before studying them; if it includes the Great Lakes, prepare them.
No. The guide referenced here reflects regulations effective 2014-03-24 and is not a new 2026 universal exam specification. Use it alongside the current published NMC module-topic index and your own approval to test.
Preparation for this credential rewards candidates who start from their approval, map it to the published module catalog, and give the skill-based chart work a long runway. Build your plan around the five groups, verify it against current NMC material, and practice at the NM1GI Exam Prep practice test site until the knowledge-based groups feel routine. For a broader look at how the pieces fit together, revisit the NM1GI Study Guide 2026 overview any time you need to reset your plan.