- What the National Mate Unlimited GL and Inland Credential Actually Is
- The Issuing Authority: USCG National Maritime Center
- The Six Preparation Areas at a Glance
- Q100 vs. Q300: Choosing Your Rules of the Road Route
- How Many Modules Will You Actually Sit?
- What You Must Master: Topic Detail by Module
- Q312 and the Great Lakes-Specific Material
- Who This Credential Serves
- Sequencing Your Preparation
- Fees, Dates and Other Details to Verify
- Frequently Asked Questions
- NMUGI here means National Mate Unlimited GL and Inland, administered by the U.S. Coast Guard National Maritime Center.
- The exam scope is NMC GLI02: Mate of Unlimited Tonnage Great Lakes and Inland.
- Great Lakes and Inland routes use Q100 for Rules of the Road; Inland routes may request Q300 instead.
- Full initial routes contain six modules for Great Lakes and Inland, or five for Inland only.
What the National Mate Unlimited GL and Inland Credential Actually Is
National Mate Unlimited GL and Inland (NMUGI) refers to the mariner credential and examination pathway for a Mate of Unlimited Tonnage, Great Lakes and Inland. In the National Maritime Center's examination numbering it is the GLI02 scope. It is a licensing examination for deck officers, not a vendor certificate or a voluntary industry badge. The people who sit it are mariners moving into officer-level watchkeeping and vessel-management responsibility on the Great Lakes and inland waters.
Because several unrelated credentials in other fields share the same acronym, it is worth being precise. Everything in this article concerns the Coast Guard deck-officer examination for Great Lakes and Inland waters. If you want a broader orientation to the terminology, our explainers on what NMUGI is and what NMUGI stands for cover the naming in more detail.
The Issuing Authority: USCG National Maritime Center
The governing body is the United States Coast Guard National Maritime Center (NMC). The NMC publishes the examination guide and the examination matrix that define which modules apply to which route. This matters for how you prepare: the content outline is not written by a training company or a commercial test vendor. It comes from the same federal source that issues the credential, so the topic lists in the published guide are the authoritative statement of what can be examined.
The Six Preparation Areas at a Glance
The published material groups the examination into six headings. These are module and topic groupings, not percentage weights. Nothing in the source material assigns a share of the exam to each heading, so any article claiming a precise weighting for them is guessing. The practical consequence is simple: you cannot safely skip a module because it looks like a smaller slice.
| Area | Module | Applies To |
|---|---|---|
| Rules of the Road: International and Inland (or Inland-only) | Q100 (or Q300) | Q100 for Great Lakes and Inland; Q300 only where Inland applicants request it |
| Deck General | Q308 | Full initial routes |
| Deck Safety | Q309 | Full initial routes |
| Navigation General Great Lakes and Inland | Q310 | Full initial routes |
| Chart Plot | Q311 | Full initial routes |
| Great Lakes Topics | Q312 | Great Lakes route only; omitted from Inland-only routes |
For a deeper walk through each heading, see our complete guide to the NMUGI exam content areas.
Q100 vs. Q300: Choosing Your Rules of the Road Route
The Rules of the Road heading is the one place where the structure is a choice rather than a fixed list. The published guide treats the two Rules alternatives as one preparation area while retaining the content of both.
- Q100 (Rules of the Road: International and Inland) covers watchkeeping, the COLREGS, and the Inland Navigational Rules. The examination guide specifies Q100 for Great Lakes and Inland.
- Q300 (Rules of the Road: Inland) covers watchkeeping and the Inland Navigational Rules only. Inland applicants use Q100 unless they request Q300.
How Many Modules Will You Actually Sit?
A common mistake is assuming the exam is a fixed seven-module event because both Rules modules appear in the published headings. They do not both apply to the same candidate. The correct picture is:
- Great Lakes and Inland, full initial route: six modules (a Rules module, Q308, Q309, Q310, Q311, and Q312).
- Inland only, full initial route: five modules, because Q312 is omitted.
- Increase from Inland to Great Lakes and Inland: Q312 is required, and Q100 is additionally required if the existing credential carries a COLREGS limitation.
This route logic is the single most important thing to confirm before you start studying, because it determines your workload. Candidates upgrading an existing credential may face a much shorter set of modules than someone sitting a full initial route. Our NMUGI requirements guide covers eligibility and prerequisites, and the NMC page remains the authority on your exact route.
What You Must Master: Topic Detail by Module
The published guide lists topics at a granular level. The blocks below summarize the real content of each module so you can see what the question pool is drawn from.
Q100 / Q300: Rules of the Road
Watchkeeping together with the collision-avoidance rules that govern how vessels interact on each body of water.
- Watchkeeping fundamentals
- COLREGS (Q100 only)
- Inland Navigational Rules (both modules)
Q308: Deck General
The broadest module, spanning seamanship, ship handling, cargo, law and shipboard management.
- Seamanship, marlinspike work, and purchases, blocks and tackle
- Navigation Safety Regulations (33 CFR 164)
- Vessel handling in rivers and estuaries, shallow-water maneuvering, bank and passing-ship interaction, berthing, unberthing, anchoring and mooring
- Dragging anchors and clearing fouled anchors; heavy weather operations
- Turn circle, pivot point, advance and transfer; maneuvering characteristics of major vessel types; wake reduction; ice operations
- Cargo stowage and security, loading and discharging, dangerous and hazardous cargo regulations, tank vessel and fuel oil operations
- National maritime law, credentialing of seamen, vessel alteration, repair and hot work, safety, ship's business, and certificates and documents required
Q309: Deck Safety
Stability, construction and damage control, plus the emergency-response material a deck officer must command.
- Principles of vessel construction, trim and stability, vessel structural members, damage control
- Marine engineering terms and vessel power plants
- Fire prevention and firefighting: classes and chemistry of fire, fire drills, systems, equipment and regulations
- Emergency procedures: abandon ship, emergency steering, man overboard, emergency towing, rescuing survivors, fire or explosion
- Communications and signals: storm, wreck, distress and special signals
- Lifesaving appliance regulations and operation
Q310: Navigation General, Great Lakes and Inland
The theory side of navigation: position determination, compasses, weather and regulations.
- Piloting, distance off, bearing problems, fix or running fix, dead reckoning, electronic navigation
- Aids to navigation; charts, navigation publications and Notices to Mariners
- Magnetic and gyro compass principles, operation, error and correction; determination of compass error; terrestrial observation
- Meteorology and oceanography: weather systems, ocean currents, weather charts and reports, tides and tidal currents
- Navigation Safety Regulations (33 CFR 164)
Q311: Chart Plot
The applied chart-work module: you work problems on a chart rather than recall facts.
- Piloting, distance off, bearing problems, fix or running fix
- Chart navigation and dead reckoning
- Electronic navigation, instruments and accessories
- Aids to navigation; charts, publications and Notices to Mariners
Notice how much overlap exists between Q310 and Q311 on piloting and chart topics. The same skills show up as theory in one module and as plotted problems in another, which makes chart-work practice unusually efficient.
Q312 and the Great Lakes-Specific Material
Q312 is the module that separates the Great Lakes and Inland credential from an Inland-only one. It draws together navigation, ship handling, stability and cargo content, with several items flagged by a Great Lakes-specific footnote in the NMC matrix. Topics include heavy weather operations, maneuvering characteristics of major vessel types, ice operations and ice navigation, wake reduction, vessel construction, trim and stability, and structural members, alongside piloting, weather, tides and cargo handling.
Key Takeaway
If you are on a Great Lakes route, Q312 is not an afterthought. It recombines material you meet in Q308, Q309 and Q310 through a Great Lakes lens, so studying those three modules thoroughly first makes Q312 far more manageable.
Who This Credential Serves
The credential qualifies a mariner to serve as a mate on unlimited-tonnage vessels operating on the Great Lakes and inland waters. The natural employers are operators of large vessels on those waters, so the credential is a gateway for deck officers whose careers are tied to Great Lakes and inland trades. Specific employer lists, wage figures and hiring conditions are not part of the published exam material, so we do not assert any here. For market context, see our pages on NMUGI jobs and the NMUGI salary guide, and for a value judgment, whether the certification is worth it.
Sequencing Your Preparation
Rather than a generic schedule, sequence your work by how the modules depend on each other. Here is one logical order for a full Great Lakes and Inland route.
Rules of the Road (Q100)
- Build fluency in watchkeeping, the COLREGS and the Inland Rules early; they underpin judgment in every later module.
Navigation and Chart Plot (Q310, Q311)
- Work piloting, fixes, dead reckoning and compass error together, since the skills overlap heavily.
Deck General and Deck Safety (Q308, Q309)
- Cover the largest topic lists here: ship handling, cargo, law, stability, firefighting and lifesaving.
Great Lakes Topics (Q312)
- Finish with the route-specific module, reusing earlier material through a Great Lakes lens, then run mixed review.
Because the headings are not weighted, do not drop a phase to save time. Our NMUGI study guide expands on resources and review methods, and the NMUGI cheat sheet is useful for last-pass revision. You can also test yourself on the main practice test site as you move through each phase.
Fees, Dates and Other Details to Verify
This article deliberately does not state a current exam fee, renewal cost, aggregate exam time or passing threshold, because the source material does not support those figures with confidence. The NMC controls fees, scheduling and evaluation procedures, and they can change. Check the NMC directly for current details, and use our pages on certification cost, exam dates, and passing score as orientation, confirming anything time-sensitive against the official source. For a sense of difficulty and outcomes, see how hard the exam is and what the pass-rate data shows.
Frequently Asked Questions
It refers to National Mate Unlimited GL and Inland, the U.S. Coast Guard National Maritime Center examination pathway (GLI02) for a Mate of Unlimited Tonnage, Great Lakes and Inland. It is unrelated to other credentials that happen to share the acronym.
No. A full initial Great Lakes and Inland route ordinarily has six modules and an Inland-only route has five. The two Rules modules, Q100 and Q300, are alternatives rather than a universal pair.
Q100 covers watchkeeping, the COLREGS and the Inland Navigational Rules, and is specified for Great Lakes and Inland. Q300 covers watchkeeping and the Inland Rules only; an Inland applicant who requests it receives a geographic COLREGS limitation.
No. The six headings are module and topic groups, not percentage weights, and no weighting is published in the source material. Prepare for every module that applies to your route.
Q312 applies to the Great Lakes route and is omitted from Inland-only routes. Increasing from an Inland credential to Great Lakes and Inland requires Q312, plus Q100 if the existing credential has a COLREGS limitation.