Page:UK Traffic Signs Manual - Chapter 4 - Warning Signs. 2013.pdf/12



Signs to diagrams 504.1 to 507.1 indicate the presence of a junction. The priority route is indicated by the thicker route symbol. This may not necessarily be a route of the same status or with the same route number. The signs may be used only on the priority route, i.e. the width of the part of the symbol indicating the approach arm must not be varied. Diagram 505.1 must not be used on an approach that does not have priority at the junction. Where advance warning of the junction is considered necessary on the non-priority approach, diagram 501 with the appropriate distance plate should be used.

Diagrams 505.1, 506.1 and 507.1 may be reversed. Diagrams 504.1, 506.1 and 507.1 may be varied so that the thicker symbol indicates the priority route, except that in diagrams 504.1 and 507.1 the thicker symbol must not indicate that a priority route is crossing ahead; the STOP or GIVE WAY sign to diagram 601.1 or 602 should be used in these circumstances. Details of the variants are shown on the working drawings (see para 1.8). No other modifications are permitted.

The sign to diagram 507.1 should be used only in the following circumstances:

(i) where the 85th percentile speed of traffic is 30 mph or less and the stagger does not exceed 50 m, or

(ii) where the 85th percentile speed of traffic is greater than 30 mph and the stagger does not exceed 120m.

If the priority route is itself the staggered route through the junction, diagram 507.1 must not be used, but a map-type advance direction sign might be beneficial. In all other cases, the two junctions should be signed individually with signs to diagram 506.1.

A supplementary distance plate to diagram 572 (see section 18) should be provided at the second sign in cases where the siting distance shown in column 4 of the table in Appendix A is greater than the distance between the two junctions.

Warning signs should not generally be used where the indication of a junction is given by a map-type advance direction sign. Nor is a warning sign normally required when a stack-type advance direction sign is used, except where the layout will not otherwise be apparent, eg at a staggered 11