Revise with instant feedback: the moment you pick an answer you see whether it was right, with the explanation where available. Untimed — ideal before you sit a mock exam. Questions you miss keep coming back until you know them.
Exam-day conditions: no feedback until you submit, each module scored separately so you can see your weak areas, plus an overall score against the pass mark, with a full question-by-question review at the end.
The real exam is passed module by module: Rules of the Road requires 90%, most other modules 70%. Chart-plotting modules are taken on paper and not included.
The free sample is 20 questions, spread across every module in the same proportions as the real exam. The full bank contains every question from the NMC's current published sample examinations for this credential, with written explanations on the popular small-vessel credentials, one-off $29, lifetime access on up to 3 devices, all credentials included.
| Delivered by | US Coast Guard National Maritime Center; exams are sat at Coast Guard Regional Exam Centers (RECs) |
|---|---|
| Official exam | Merchant Mariner Credential (MMC) endorsement examinations |
| Questions | Set per credential in your Approval to Test letter; the NMC does not publish module question counts |
| Time | Each module is sat in a 3½-hour examination period; modules are taken in consecutive periods |
| Passing score | Rules of the Road 90%; Deck General and Deck Safety 70% (NMC notice, January 2018) |
| Exam fee | Set by 46 CFR 10.219: for an original officer endorsement, evaluation $100, examination $95 (lower level) or $110 (upper level), issuance $45 |
| Pre-licensing or eligibility | Apply to the Coast Guard first; you need the NMC's Approval to Test letter before you can book. The application stays valid for 12 months |
| Book your exam | dco.uscg.mil/nmc/Examinations |
Checked 11 October 2026 from the official sources below. Rules and fees change, so confirm with US Coast Guard National Maritime Center; exams are sat at Coast Guard Regional Exam Centers (RECs) before you book.
Wheelhouse is a $29 question bank built from the Coast Guard's own sample exams, not an approved course. Here is how it compares with the courses and tools mariners usually consider, including where they are the better choice. See the comparison with Mariners Learning System, Sea School, MPT and others.
You must pass each module separately. Most modules require 70% to pass.
The exam covers 2 modules: Tankship Dangerous Liquids, Tankship Liquefied Gases.
This page includes free sample questions drawn from the official USCG sample examinations, with a full bank of around 99 questions across all modules available with lifetime access.
Every question comes from the U.S. Coast Guard National Maritime Center's published sample examinations, which are U.S. government works in the public domain. Wheelhouse Prep is not affiliated with or endorsed by the U.S. Coast Guard.
No. The free practice tests work in your browser with no signup. Your score history is saved on your own device.
Last updated 12 June 2026. The bank is refreshed whenever the Coast Guard publishes revised sample examinations.
A selection of free questions from the official USCG sample examinations. Use the interactive modules above for timed, scored drills.
How can you determine which grades of cargo a tank vessel is permitted to carry?
What causes the most frequent incidents of pollution during tanker operations?
46 CFR directs the location of fuel oil sounding tubes and access openings for fuel oil tanks on cargo vessels. Where can the tubes be located?
Who enforces the U.S. pollution regulations that apply to ships?
Your vessel is taking on cargo oil when a small leak develops in the hose. You order the pumping stopped. What action should you take before you resume pumping?
Who must supervise functions aboard a tanker or tank barge such as connecting, disconnecting, and topping off?
When you notice oil on the water near your vessel while taking on fuel, what should your first action be?
If you observe any situation which presents a safety or pollution hazard during the fuel transfer operations, which action should you take FIRST?
What term is not considered a "discharge" as it applies to the U.S. pollution regulations?
What do the emergency shutdown requirements of U.S. regulations apply to?
When loading bulk liquid cargo, what is the FIRST action you should take if a cargo valve jammed open?
Which statement is TRUE concerning combustible gas indicators?
Oil product samples should be taken at the commencement and completion of loading operations. As the person in charge, where should the final samples be taken?
What is the primary hazard of liquefied petroleum gas and liquefied natural gas?
U.S. regulations require an emergency means of stopping the flow of oil or LNG during transfer operations. The emergency means may be which of the following?
Which of the following is the pipe used to connect two separate piping systems on a tank vessel?
Which of the following describes a liquefied gas?
In what condition is LNG transported?
Which of the following is a safety consideration when dealing with Liquefied Gas?
What is the lowest temperature at which a liquid will give off sufficient vapors to form a flammable mixture with air?