Zig-zag lines
10.—(1) The pattern of the central zig-zag lines may be reversed or, on a road having a carriageway not more than 6 metres wide, those lines may be omitted altogether so long as they are replaced by the road marking shown in diagram 1004 in Schedule 6 to the 1994 Regulations.
(2) Subject to sub-paragraph (4) the number of marks in a zig-zag line shall not be less than 8 nor more than 18 and a zig-zag line need not contain the same number of marks as any other zig-zag line.
(3) Each mark in a zig-zag line shall be coloured white and may be illuminated by retroreflecting material.