Clause 2 Vertical positioning and spacing of lights

(1) On a power-driven vessel of 20 metres or more in length, the masthead lights must be placed as follows—

(a) the forward masthead light or, if only one masthead light is carried, then that light, at a height above the hull of not less than 6 metres, AND if the breadth of vessel exceeds 6 metres, then at a height above the hull not less than such breadth,

BUT the light need not be placed at a greater height above the hull than 12 metres; and

(b) when two masthead lights are carried the after one must be at least 4.5 metres vertically higher than the forward one.

(2) The vertical separation of masthead lights of power-driven vessels must be such that in normal conditions of trim the after light will be seen over and separate from the forward light at a distance of 1000 metres from the stem when viewed from sea-level.

(3) The masthead light of a power-driven vessel of 12 or more metres but less than 20 metres in length must be placed at a height above the gunwale of not less than 2.5 metres.

(4) A power-driven vessel of less than 12 metres in length may carry the uppermost light at a height of less than 2.5 metres above the gunwale. However when a masthead light is carried in addition to sidelights and a sternlight or the all-round light prescribed in rule 22.23(3)(a) is carried in addition to sidelights, then such a masthead light or all-round light must be carried at least 1 metre higher than the sidelights.

(5) One of the two or three masthead lights prescribed for a power-driven vessel engaged in towing or pushing another vessel must be placed in the same position as either the forward masthead light or the after masthead light,

BUT, if carried on the aftermast, the lowest after masthead light must be 4.5 metres vertically higher than the forward masthead light.

(6) Subject to Appendix 1.12, the masthead light or lights prescribed in rule 22.23(1) must be so placed as to be above and clear of all other lights and obstructions,

EXCEPT that when it is impracticable to carry the all-round lights prescribed by rules 22.27(2)(a) or 22.28 (all-round lights for vessels restricted in their ability to manoeuvre and vessels constrained by their draught) below the masthead lights, they may be carried—

(a) above the after masthead light(s); or

(b) vertically in between the forward masthead light(s) and after masthead light(s), provided that the requirement of Appendix 1.3(3) (relating to horizontal distance) is complied with.

(7) The sidelights of a power-driven vessel must be placed at a height above the hull not greater than three-quarters of that of the forward masthead light. They must not be so low as to be interfered with by deck lights.

(8) The sidelights, if in a combined lantern and carried on a power-driven vessel of less than 20 metres in length, must be placed not less than 1 metre below the masthead light.

(9) If these rules prescribe two or three lights to be carried in a vertical line, they must be spaced as follows—

(a) on a vessel of 20 metres in length or more, such lights must be spaced not less than 2 metres apart, and the lowest of these lights must, except where a towing light is required, be placed at a height of not less than 4 metres above the hull; and

(b) on a vessel of less than 20 metres in length, such lights must be spaced not less than 1 metre apart and the lowest of these lights must, except where a towing light is required, be placed at a height of not less than 2 metres above the gunwale; and

(c) when three lights are carried, they must be equally spaced.

(10) The lower of the two all-round lights prescribed for a vessel when engaged in fishing must be at a height above the sidelights not less than twice the distance between the two vertical lights.

(11) The forward anchor light prescribed in rule 22.30(1), when two are carried, must not be less than 4.5 metres above the after one. On a vessel of 50 metres or more in length, this forward anchor light must be placed at a height of not less than 6 metres above the hull.