1. The triangular sign must not be placed unless placed with a plate showing the applicable first plate legend indicated in column 4 of the sign table in Part 2 at the item number in question.
2. The sign may be fitted to the rear of a road maintenance vehicle.
3. The two triangular signs must be placed together (with or without an associated plate).
4. The triangular sign must be placed with its upper associated plate (whether or not the lower plate is also included).
5.—(1) The sign (“an edge of carriageway sign”) must be placed so that the top of the sign is not less than 550 mm nor more than 1000 mm above the surface of the adjacent carriageway.
(2) Where an edge of carriageway sign is mounted on a post specifically provided for the purpose that part of the post which extends above ground level may be—
(a)of any single colour; or
(b)coloured black and white in alternate horizontal bands, each band being not less than 225 mm or more than 350 mm deep.
(3) An edge of carriageway sign must be erected to display—
(a)the colour red on the left hand edge of the carriageway as viewed by the drivers of approaching vehicles; and
(b)the colour white on the right hand edge of the carriageway when so viewed, unless the edge is the edge of the carriageway of a dual carriageway road or a one-way road when the colour amber must be displayed.