International Regulations for Preventing Collisions at Sea

The International Regulations for Preventing Collisions at Sea 1972, also known as Collision Regulations (COLREG), are published by the International Maritime Organization (IMO) and set out, among other things, the "rules of the road" or navigation rules to be followed by ships and other vessels at sea to prevent collisions between two or more vessels. COLREG can also refer to the specific political line that divides inland waterways, which are subject to their own navigation rules, and coastal waterways which are subject to international navigation rules.

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