Module 5 of 17
International Regulations for Preventing Collisions at Sea — steering rules, lights, and shapes.
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The International Regulations for Preventing Collisions at Sea (COLREGs, also known as IRPCS) are the 'rules of the road' at sea. They apply to all vessels on the high seas and connected...
Rule 2 underpins every other rule. It states that nothing in the COLREGs shall exonerate any vessel, owner, master, or crew from the consequences of neglecting the rules, or neglecting an...
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 t...
You must use all available means to determine if a risk of collision exists. If there is any doubt, assume it does exist.
Any action taken to avoid collision must be positive, made in ample time, and large enough to be readily apparent to the other vessel. Small, indecisive course changes are dangerous — the...
Rule 12 (Sailing vessels): When two sailing vessels meet, the vessel on port tack gives way to the vessel on starboard tack. If both are on the same tack, the windward vessel gives way. I...
Rule 18 establishes a hierarchy of who gives way based on vessel type. In general, more manoeuvrable vessels give way to less manoeuvrable ones.
Rule 16 (Give-way vessel): Must take early and substantial action to keep well clear.
Rule 9 (Narrow Channels): Keep to the starboard side. Vessels under 20m or sailing vessels must not impede vessels that can only navigate within the channel. Do not cross a narrow channel...
Power-driven vessels display: masthead light(s) (white, 225°), sidelights (red port, green starboard, each 112.5°), and a stern light (white, 135°). Vessels over 50m show two masthead lig...
Day shapes are black shapes hoisted where they can best be seen during daylight to indicate a vessel's status or activity. They supplement or replace lights during the day and are require...
Rule 19 applies to vessels not in sight of one another when navigating in or near an area of restricted visibility (fog, heavy rain, snow, etc.). It replaces Rules 12–18 when vessels cann...
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