What is the required height above the hull of a masthead light on a vessel of 20 metres or more?

The required height for a masthead light on a vessel of 20 metres or more is stipulated to be not less than 6 metres above the hull, or a height equivalent to the breadth of the hull, with an upper limit of 12 metres. This requirement is in place to ensure that the light is visible over a significant distance and is adequately positioned to avoid obstruction from the vessel's superstructure or other parts of the hull.

This standard is grounded in the need to ensure that vessels are easily identifiable at sea, particularly in low visibility conditions. The height requirement helps differentiate performance and capability among vessels of various sizes while maintaining uniformity in navigation practices. Thus, by ensuring that the masthead light is properly elevated, it aids in promoting safe navigation and collision avoidance—fundamental aspects of maritime safety.