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International COLREGs Study Companion
Direct answer
International COLREGs decisions, lights, shapes, sound signals, and mixed scenarios with national-rule boundaries kept explicit. Compass provides independent knowledge preparation only. It does not administer an official examination, award certification, demonstrate practical competence, or replace current instructions from an authorized provider or authority. National enactments, inland rules, local regulations, and current notices remain separate.
- Price
- £14.99 once
- Course size
- 10 modules
- Access
- Lifetime access
- Format
- Independent online study companion
Product tour
Try the revision loop here
This is a working, course-specific sample. Read one rule, answer a real-style question, flip a recall card, and see how the next action is chosen.
Open the full free moduleLookout, risk, and early action
One rule, explained clearly
COLREGs decisions start with an effective lookout and an honest assessment of collision risk. A steady bearing can be important evidence, but the full picture includes range, aspect, vessel status, visibility, traffic, and the limits of every sensor. Any avoiding action must be early, substantial, safe, and checked to confirm that it works.
Course route
Learn the knowledge, then take it afloat with an instructor
Scope, Responsibility, and Definitions
Where the international rules apply, responsibilities under Rules 1 and 2, vessel-status definitions, and why no memorized hierarchy removes the need for seamanship.
Open moduleLookout, Safe Speed, Risk, and Action
Rules 5–8: lookout, safe speed, risk of collision, radar evidence, early substantial action, and verifying that action works.
Open moduleOvertaking, Head-On, and Crossing
Rules 13–17 in sight of one another, including classification, give-way action, stand-on duties, and escalation when the expected action does not occur.
Open moduleSailing Vessels, Channels, and Traffic Separation
Sailing-vessel encounters, responsibilities between vessels, narrow channels, traffic separation schemes, and the distinction between keep-clear and do-not-impede duties.
Open moduleRestricted Visibility
Rule 19 conduct when vessels are not in sight, safe speed, engines readiness, radar detection, avoiding-action cautions, fog signals, and action on hearing a signal forward of the beam.
Open moduleNavigation Lights
Rules 20–31, light arcs, aspect, making-way lights, vessel status, length-dependent additions, and distinguishing a recipe from a complete identification.
Open moduleDay Shapes
Balls, cones, diamonds, cylinders, combinations, vessel conditions, making-way context, and matching daytime and nighttime signals.
Open moduleSound Signals
Short and prolonged blasts, manoeuvring signals in sight, restricted-visibility signals, bell and gong patterns, intervals, and listening decisions.
Open moduleDistress and Attention Signals
Annex IV distress signals, Rule 36 attention signals, avoiding confusion with navigation aids, and the practical boundary between recognition and emergency operation.
Open moduleMixed Scenarios and National Boundaries
Integrated encounter decisions, changing visibility, vessel-status uncertainty, local and inland rules, national modifications, and briefing defensible action.
Open moduleWhat the companion includes
Clear knowledge and practical boundaries
- Original lessons and explanations
- At least 18 explained questions and 12 flashcards per module
- Three 40-question mixed knowledge assessments
- Worldwide terminology, jurisdiction, and primary-source context
- Practical-awareness prompts clearly separated from assessed knowledge
Not included
- A national licence, certificate, endorsement, or official examination
- National inland rules, prescriptions, notices, or sailing instructions
- Copied rulebook, chart, assessment, or official diagram content
- A substitute for lookout, seamanship, or current local information
- A guarantee of acceptance by an authority, club, school, or operator
Editorial record
Primary-source review
International principles are reviewed against current primary sources. National law, prescriptions, sailing instructions, equipment requirements, and local notices must be checked separately.
- IMO COLREGs convention overview
Primary convention structure for steering, sailing, lights, shapes, sound, and distress-signal review.
- USCG Navigation Rules
International and Inland Navigation Rules source and U.S. boundary context.