Module 5 of 17
COLREGs
International Regulations for Preventing Collisions at Sea — steering rules, lights, and shapes.
What Are the COLREGs?
The International Regulations for Preventing Collisions at Sea are known as COLREGs or IRPCS. They are the rules of the road at sea and explain how vessels should keep a lookout, assess collision risk, give way, stand on, display lights and shapes, and make sound signals.
COLREGs apply to all vessels on the high seas and connected navigable waters. As a Day Skipper, you need full knowledge of the steering and sailing rules, especially Rules 5, 7, 8, 9, 10, and 12-19.
The regulations are divided into parts: Part A (General), Part B (Steering and Sailing Rules), Part C (Lights and Shapes), Part D (Sound and Light Signals), and Part E (Exemptions). In exam questions, always identify the situation first: overtaking, head-on, crossing, sailing vessel, narrow channel, restricted visibility, or special vessel type.
Key Points
- COLREGs apply to ALL vessels on navigable waters
- Part B (Steering and Sailing Rules) requires full knowledge
- Rules exist to prevent collisions — both vessels share responsibility
| Rule / part | Topic | Day Skipper exam focus |
|---|---|---|
| Rule 5 | Look-out | Sight, hearing, radar, AIS, and all available means |
| Rule 7 | Risk of collision | Constant bearing, decreasing range means danger |
| Rule 8 | Action to avoid collision | Act early, positively, and obviously |
| Rules 12-15 | Sailing, overtaking, head-on, crossing | Who gives way in common encounter situations |
| Rule 18 | Vessel hierarchy | Power, sail, fishing, NUC, RAM, constrained by draught |
| Part C | Lights and shapes | Identify vessel type and status by day or night |
| Part D | Sound and light signals | Restricted visibility and manoeuvring signals |
Common Questions
What does COLREGs stand for?
COLREGs stands for the International Regulations for Preventing Collisions at Sea. They are also known as IRPCS.
Which COLREGs rules are most important for Day Skipper?
Day Skipper candidates need especially strong knowledge of the steering and sailing rules, including Rules 5, 7, 8, 9, 10, and 12-19.
Do COLREGs apply to sailing yachts?
Yes. COLREGs apply to all vessels, including sailing yachts. A sailing yacht using its engine is treated as a power-driven vessel.
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 (including radar), so as to make a full appraisal of the situation and the risk of collision.
This is one of the most fundamental rules. A good look-out means using your eyes, ears, radar, AIS, and any other means. It applies in all conditions, day and night.
Key Points
- Look-out by sight AND hearing at all times
- Use all available means including radar and AIS
- Applies in all weather and visibility conditions
7 more sections in this module — full lesson, quizzes, flashcards, and interactive tools with Day Skipper Revision (£4.99).
Unlock the complete module
Get every section, quizzes, spaced-repetition flashcards, and mock exams — one-time purchase.