During which two conditions are lights required to be displayed on vessels?

Lights are required to be displayed on vessels during night and restricted visibility conditions to ensure safety on the water. At night, the illumination of navigation lights helps in identifying the presence and type of vessel, as well as its direction and status. This is critical for avoiding collisions in the dark.

Restricted visibility refers to conditions where visibility is significantly limited, such as during fog, heavy rain, or snow. In these situations, vessels must display their navigation lights to be seen by other vessels nearby, as well as to demonstrate their own course and activities, helping all mariners make informed decisions.

Displaying lights in these situations is mandated by the International Regulations for Preventing Collisions at Sea (COLREGs), reinforcing the importance of visibility and communication between vessels to reduce the risk of accidents.