What is the minimum range of all-round lights on vessels under 12 meters?

The minimum range of all-round lights on vessels under 12 meters in length is indeed 2 miles. According to the COLREGs (International Regulations for Preventing Collisions at Sea), the requirements for navigation lights are specified to enhance visibility and safety at sea. For vessels under 12 meters, the regulations stipulate that all-round lights must be visible for at least 2 nautical miles. This range ensures that smaller vessels are visible to other boats and can effectively signal their presence, especially in conditions where visibility may be reduced.

The other distances mentioned, 3 miles, 4 miles, and 6 miles, exceed the required minimum visibility range for these smaller vessels. Larger vessels have different regulations that may require lights with a greater visibility range, but for vessels under 12 meters, adhering to the 2-mile range is sufficient and compliant with the safety standards established by the COLREGs.