Which of the following vessels are exempt from showing lights when at anchor in specific conditions?

Vessels under 20 meters in length are indeed subject to specific exemptions regarding the display of anchor lights under certain conditions. According to the International Regulations for Preventing Collisions at Sea (commonly known as COLREGs), vessels that are less than 20 meters in length may be exempt from the requirement to show anchor lights if they are not engaged in fishing or are anchored in areas where they are not likely to interfere with other vessels.

This exemption is based on practical considerations; smaller vessels may not have the means to display the lights due to their size and the intended use of their anchorage space, especially in quiet or less trafficked waters. Additional guidelines may apply depending on their activity or location.

In contrast, vessels like commercial fishing vessels, yachts over 30 meters, and government vessels typically do not have such exemptions and are required to display appropriate anchor lights to ensure they are visible to other vessels in the vicinity, regardless of their operational status. This is part of maintaining safe navigation and preventing collisions on the waterways.