Signs to be placed only on specified types of road
15.—(1) The signs shown in diagrams 823, 824, 825, 868, 868.1, 872.1, 873, 874, 875, 876 and 2713 may be placed only on or near—
(a)a motorway when the colour of the background of the sign is blue;
(b)a primary route when the colour of the background of the sign is green; or
(c)a non-primary route when the colour of the background of the sign is white.
(2) The sign shown in diagram 872.1 may only be placed on a dual carriageway road or a one-way road.
(3) The sign shown in diagram 877 may be placed only on or near—
(a)a motorway exit slip road when the colour of the background of the sign is blue;
(b)a primary route when the colour of the background of the sign is green; or
(c)a non-primary route when the colour of the background of the sign is white.