How does COLREGs define a “vessel”?

• A. An object that cannot move and is used for marks.
• B. Any floating device that does not navigate.
• C. A vessel associated with a navy.
• D. A craft or structure capable of navigation and meeting at sea or inland waters (as defined in the conventions).

Answer: (D)

COLREGs define vessel as any watercraft used or capable of being used as a means of transportation on the water, spanning all forms that can navigate on sea or inland waters. This broad idea includes ships, boats, sailing craft, seaplanes, and even floating structures that can actually move and be used for transporting people or goods. The key points are the ability to navigate and the geographic scope—sea and inland waters as defined by the conventions. That’s why the phrasing describing a craft or structure capable of navigation and meeting on sea or inland waters best matches the official definition. Im Moves that cannot navigate aren’t vessels, and things limited to marks or to navy-only use don’t fit the universal, transport-capable scope of COLREGs.