Recognizable Layout Of Roads; Final Report Of The Predictability Projects In SWOV's 2003-2006 Research Programme

Herkenbare vormgeving van wegen; Eindrapport van de herkenbaarheidsprojecten in het SWOV-programma 2003-2006

This final report summarizes what is known about the recognizability of roads and what recent SWOV research on this has produced. It first explains what the underlying idea is of the Sustainable Safety principle of predictability. Then it sketches the current situation in practice and considers how the Essential Recognizability Characteristics ('EHK') guideline materialized and was implemented. Much of the information comes from an inventory study about recognizable layout and predictable behaviour. This inventory study was the first one in the SWOV project on the predictability of roads (part of the research programme 2003-2006). SWOV carried out two empirical studies based on this inventory study. This involved a study on how recognizable rural roads currently are for road users, and a study about how a recognizable road environment can affect driving behaviour. Besides this, the authors studied the extent to which public information can contribute towards roads being better recognizable. The results of these studies showed that, at the present, the various road types in the Netherlands are not yet sufficiently distinguishable from each other for road users and that it will not automatically be the case with only the EHK marking. On the one hand this has to do with a lack of uniformity in the design within road types, and with the chosen design elements, especially on rural distributor roads and regional through-roads. People indicate that, with regard to road categories, they mainly pay attention to the type of road marking, the road width, and the 'design speed'. Of these characteristics, the non-compulsory cycle lanes on access roads clearly distinguish them from other road types, and also evoke the correct expectations about the possible presence of bicycles and mopeds on the road. On rural distributor roads and regional through-roads, much more attention is paid to the separation of driving directions because this indicates the overtaking rules. What does not or hardly receive any attention is the edge marking on these road types, whereas this is the only characteristic that is uniform within these road types. With this characteristic, a distinction could be made between rural distributor roads and regional through-roads. In order to achieve the desired driving behaviour, it is not only important that roads can be distinguished from each other, which is why a uniform road design within road types must be carried out, but also which design elements achieve this uniformity. To do this, knowledge about credible speed limits, for example, can be applied. In order to achieve a complete sustainably safe infrastructure, other Sustainable Safety principles would also have to be included in the ultimate road layout. Public information can contribute to making roads recognizable. This applies to both distinguishing the correct road types as well as evoking the correct expectations. However, the authors have not been able to show that such information also influences driving behaviour. This is directly influenced by the road layout. Based on the results of the studies, the authors recommend a greater degree of layout uniformity per road category to achieve a better recognizability of roads in the future. This uniformity is especially important for those elements that road users pay attention to. For rural distributor roads and through-roads this is not so much the edge marking but more the separation of driving directions. Furthermore, to achieve the desired driving behaviour it is essential to have uniformity using those elements that can influence this behaviour. For example, knowledge of credible speed limits could be used. For a real sustainably safe traffic system, it is important that ultimately, all Sustainable Safety principles are integrally included in the road design. Again, the authors would like to emphasize how important it is to achieve Essential Characteristics and not to limit ourselves to Essential Recognizability Characteristics. Additional information can help to make roads more recognizable for road users. Information is less useful for achieving the desired driving behaviour. In this report the authors also make recommendations for further research. As yet there are no guidelines for transitions from one road type to an other. The layout of such transition areas can make road users aware that other behaviour is expected from them and that they themselves should have other expectations about other road users. Such further research about the recognizability of transition areas would be an interesting subject for the coming years.


  • Dutch

Media Info

  • Media Type: Web
  • Pagination: 38p

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Filing Info

  • Accession Number: 01052035
  • Record Type: Publication
  • Report/Paper Numbers: R-2006-18
  • Files: TRIS
  • Created Date: Jun 27 2007 5:56PM