COLREGS Rules of the Road Practice Test: What to Know Before Exam Day

More candidates fail the Rules of the Road module than any other section of the USCG licensing exam. That's not because it's conceptually hard — it's because the NMC questions are precision instruments designed to catch exactly the candidates who understand the rule in general but don't know it cold. One-word differences between Rules matter on this exam.

This is a guide to how COLREGS practice tests actually work, what categories of questions appear most frequently, and how to build the kind of knowledge that holds up under exam pressure.

The COLREGS Framework

The International Regulations for Preventing Collisions at Sea, 1972 (COLREGS 1972) is the foundational international convention. The U.S. Inland Navigation Rules (33 CFR Part 83) apply on U.S. inland waters — rivers, bays, sounds, and the Great Lakes — and differ from COLREGS in specific, tested ways.

For near coastal licensing exams (OUPV near coastal, Master 100 GT near coastal, Master 200 GT), you need to know both COLREGS and Inland Rules, and you need to know where they differ.

The Rules of the Road module: 50 questions, 70% passing score, separate from all other modules.

How the 38 Rules Are Organized

Understanding the structure prevents you from getting lost in individual rule text:

Part A — General (Rules 1-3): Application, definitions, and responsibility. Rule 2 (Responsibility) is often tested: nothing in the Rules exonerates a vessel from negligence or from the consequences of deviation.

Part B — Steering and Sailing Rules (Rules 4-19):

• Rules 4-10: Conduct of vessels in any condition of visibility — lookout, safe speed, risk of collision, action to avoid collision, narrow channels, traffic separation
• Rules 11-18: Conduct of vessels in sight of one another — sailing vessel priority, overtaking, head-on, crossing, action by give-way, action by stand-on, responsibilities between vessels

Part C — Lights and Shapes (Rules 20-31): When lights must be shown, arc widths, lights for every vessel category.

Part D — Sound and Light Signals (Rules 32-37): Definitions, maneuvering signals, restricted visibility signals, distress signals.

Annex I-IV: Positioning of lights, additional signals, technical specifications.

The Most Commonly Tested Rules

Rule 5 — Look-Out

"Every vessel shall at all times maintain a proper look-out by sight and hearing as well as by all available means appropriate in the prevailing circumstances and conditions so as to make a full appraisal of the situation and of the risk of collision."

The NMC loves to test what "all available means" includes (radar, VHF, AIS) and what circumstances affect look-out requirements (restricted visibility, high traffic density).

Rule 8 — Action to Avoid Collision

The requirement that any action taken to avoid collision must be large enough to be readily apparent to the other vessel. A small course change in a crossing situation is specifically called out as improper. Questions often test whether a given action meets the "readily apparent" standard.

Rule 9 — Narrow Channels

A consistent exam favorite. Key points:

• A vessel proceeding along the course of a narrow channel shall keep as near to the outer limit of the channel which lies on her starboard side as is safe and practicable
• A vessel of less than 20 meters shall not impede the passage of a vessel that can safely navigate only inside a narrow channel
• COLREGS and Inland differ here: the Inland Rules specifically address vessels navigating downbound on rivers and the Western Rivers rules for meeting situations

Rules 13, 14, 15 — Overtaking, Head-On, Crossing

Rule 13 (Overtaking): Any vessel coming up with another from a direction more than 22.5 degrees abaft the beam is overtaking. The overtaking vessel must keep clear — even if it's technically a sailing vessel with right of way over a power-driven vessel in normal circumstances. This override is a common exam point.

Rule 14 (Head-On): When two power-driven vessels are meeting head-on, both shall alter course to starboard. The exam often asks about the determination — if you're uncertain whether a situation is head-on or crossing, treat it as head-on.

Rule 15 (Crossing): The vessel that has the other on her starboard side is the give-way vessel. Tested question: what is the give-way vessel required to do (avoid passing ahead of the stand-on vessel), and what is the stand-on vessel permitted to do when the give-way vessel isn't taking action (Rule 17 — take action when collision is imminent).

Rule 18 — Responsibilities Between Vessels

The hierarchy: power-driven vessels give way to sailing vessels, sailing vessels give way to vessels not under command, vessels not under command are considered above vessels restricted in ability to maneuver. Know this hierarchy cold, and know the exceptions (Rule 18 doesn't relieve vessels being overtaken of the obligation to keep clear).

Rules 23-31 — Lights

The light rules are tested by three methods:

1. Describe the lights for vessel type X (power-driven vessel under 50m underway, trawler fishing, vessel being towed, etc.)
2. You see these lights — what is the vessel? (three-option identification)
3. Are these lights correct/incorrect for this vessel? (error-spotting)

Arc widths you must know without thinking:

• Masthead light: 225° (112.5° either side of dead ahead)
• Sidelights: 112.5° each (112.5° forward of the beam on each side)
• Sternlight: 135° (67.5° either side of dead astern)
• All-round light: 360°
• Yellow towing light: 135° (same as sternlight)

Where Inland Rules Differ from COLREGS

The NMC specifically tests candidates on these divergences for near coastal exams:

Sound signals in sight of one another: COLREGS specifies that whistle signals indicate actual course changes (1 short blast = I am altering course to starboard). Inland Rules retain the proposal-and-agreement format (1 short = I intend to leave you on my port side; answer = same signal means agreement). This is one of the most frequently tested differences.

Traffic separation schemes: COLREGS Rule 10 applies in TSS areas worldwide. The U.S. Inland Rules have a different rule structure for river traffic on the Western Rivers.

Bends: Inland Rule 9 specifies sound signals when approaching bends (1 prolonged blast). COLREGS do not have this specific requirement.

Overtaking in narrow channels: Inland Rules have a specific signal exchange procedure (2 prolonged + 1 short to indicate intent to overtake on starboard, 2 prolonged + 2 short to indicate intent to overtake on port).

Study Strategy for Rules of the Road

Read the Rules once in full before drilling questions. Don't start practicing before you have a mental map of the 38-rule structure.

Then drill by category: Do all of Part B (steering and sailing) first, then all of Part C (lights), then Part D (sound signals). Cross-category confusion is a common problem that drilling by category solves.

Do every question in the NMC bank at least twice. The bank is public. Questions don't change. Understanding why each wrong answer is wrong is as important as knowing the right answer — the exam uses the same distractors.

Pay special attention to exceptions and overrides. The exam is designed around these. The base rule isn't usually what's tested — it's the exception to the rule, or the rule that overrides another rule.

Practice Test Scoring Goals

Before you sit for the actual exam, you should be consistently scoring 82-85% or higher on practice tests. At 70% required, you want a buffer. The exam environment creates performance drops — time pressure, unfamiliar environment, the test anxiety of knowing this is the real thing.

If you're consistently scoring below 75% on practice tests in the final two weeks before your exam date, consider deferring. A failed module means re-sitting, paying the fee again, and potentially waiting weeks for an appointment.

Practice with Binnacle School

The Rules of the Road module rewards systematic, specific practice — not just reading the Rules and hoping. [Binnacle School](/school) gives you COLREGS practice tests organized by rule category, with explanations that tell you why each answer is right or wrong and flag where Inland Rules differ from COLREGS.

Drill the Rules the way the NMC asks them. Start your Rules of the Road practice session →

Binnacle AI is not affiliated with the U.S. Coast Guard or the NMC. COLREGS 1972 and U.S. Inland Navigation Rules (33 CFR Part 83) are the governing documents — always refer to the current official text. This article is informational, not legal advice.