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 are known as COLREGs or IRPCS. They are the rules of the road at sea and explain how vessels should keep a lookout, assess c...
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...
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