ANWB has initiated a project to improve the safety of the cycling infrastructure in the Netherlands – and, in the longer term, also in other countries: the Safe Cycling Network project. This project was inspired in part by the international European Road Assessment Programme (EuroRAP/iRAP). The objective is to develop a system of expertise, an expert system, to help road authorities assess the cycling infrastructure (and therefore bicycle safety). To this end it is especially important to proactively take a survey of unsafe cycling infrastructure and take measures. ANWB asked SWOV to provide the scientific justification of the project, which is embodied in this report.
The system came about as a result of a number of phases, the first of which comprised a desk study and consultation with bicycle safety experts (road authorities). This focused principally on the importance of risk-enhancing factors for cyclists. Based on this a set of indicators for lack of safety in the cycling infrastructure was selected. It was then determined how road authorities can use these indicators to assess the cycling infrastructure in practice. Pilot projects were launched in two municipalities (Harderwijk and Goes) to gain practical experience of the system. Additionally, a perception survey was carried out in which cyclists assessed the safety of bicycle facilities. These new practical insights improved the practicability of the expert system.
The result of the project is a system that is described in Appendix A. To be able to apply the expert system, a working method involving two instruments was chosen. Firstly, a checklist (interface) was developed with indicators that impact on the safety of the cycling infrastructure. Secondly, a procedure was developed that allows road authorities to assess the cycling infrastructure on the basis of the interface and 360-degree panoramic images of the cycling infrastructure (supplied by CycloMedia).
In practice, the system proved useful for the systematic gathering of data on the safety of the cycling infrastructure and comparing this data. The system is also suitable for identifying locations that (based on indicators) are assessed as unsafe.
Furthermore, the expert system needs to be expanded or data need to be entered for the following topics:
- Insight into the relationship between a location that is assessed as unsafe and the risk of a cycling crash (validity of the system). In particular, there is a lack of essential data on:
- the volume of bicycle traffic (exposure);
- the location, facts and consequences of cycling crashes;
- weighting factors of indicators with which a final score can be determined for the safety of the cycling infrastructure;
- the degree of validity of the expert system: is there a correlation between the final score of locations and the risk of cycling crashes at those locations when making safety predictions (cycling crashes);
- formula in which the indicators and weighting factors are incorporated in a single final score for each road section (the output of the system).
- Knowledge about the extent to which different people encode the indicators of cycling infrastructure in the same manner (reliability).
- Applying the system outside the Netherlands to ensure that it is also valid for the local cycling infrastructure in other countries.
The following recommendations are made on the basis of the conclusions:
- Seek alliance with the EuroRAP method
This offers the following possibilities:
- Interchange of knowledge for the purpose of further developing the system;
- Application of the expert system outside the Netherlands and adapting it to the prevailing situation there;
- Management of the system so that it is possible to compare research results (inside and outside the Netherlands).
- Decide the validity (relationship between the safety score and the risk of a cycling crash) of the system.
To determine the validity we recommend:
- ensuring that regional and local government make more data available on dynamic factors, in particular the volume (exposure) of bicycle traffic;
- ensuring that cycling crashes are properly registered (location, facts, consequences). for example, ANWB can encourage research into the application of mobile technology and services that allow cyclists to register crashes with a hotline;
- testing the safety score empirically (determine the correlation between the safety score and the risk of a cycling crash).
- Establish whether the indicators have been coded reliably by finding out whether they are consistent if they have been set by different people.
- Ensure that road authorities are involved in further developing the safety score of the system by carrying out pilots in practice, such as the pilots in Fryslân.