Additional Dual Carriageway Signs 818

I'm looking for thoughts on providing an additional dual carriageway sign within 50m of the nose of an approaching dual carriageway (national speed limit applies). There already are signs, as required by TSRGD Ch4 at appendix A distance on both sides of the carriageway, but there is pressure for an additional sign. Anybody think it's OK to place the additional sign? is there a reference or precedent?
Many thanks


  • I think it depends upon where the 'pressure' is coming from and whether it has any engineering basis. What is the problem that an additional sign attempts to solve? The new TSM Chapter 1 is very much of the view that each sign needs a clear reason for being there.

    But if there is a definite safety issue that an extra sign would help to mitigate, then my opinion is go for it. Where would the extra sign be put?
  • Thanks Simon, I appreciate your thoughts, the sign would be put where the final decision point would be in order to stop drivers taking the wrong side of the dual c/w, the police are for it, I think the sign would help mitigate the problem, but I don't want a clash with design guidance.
  • I think if there is a significant risk of drivers going down the wrong carriageway, additional or larger regulatory signs should be considered, rather than the informatory diag. 818.

    What about a larger or higher 610 'keep left' arrow at the start of the central reserve, and/or a pair of 616 'no entries' on the wrong carriageway? Or possibly double while lines or hatching to keep traffic on the correct side of the road before the DC starts? All just ideas that may or may not work for your particular situation.
  • Thanks again Simon,
    too narrow for a larger 610, but I'm happier now with the additional 818 plus the road marking we propose. I'll feedback to the designer and the asset team and let them decide as it's a bit of a grey area, so erring on the side of caution is better.
  • Thanks everyone, decision made now.
Sign In or Register to comment.

Welcome to the forum

Please sign in or register. You don't need to be an IHE member to take part.