Including safety effects in cost benefits analysis.

This study considers how safety effects can preferably be measured, valued economically and be presented amongst other project effects in the evaluation of transport infrastructure. The newly developed framework aims at improving the transparency and consistency of the current framework on the evaluation of transport projects in the Netherlands, by including in the equation risks on traffic safety, on transport and storage of dangerous goods, and on personal safety. Since 2000, the Dutch Ministry of Transport prescribes the OEI assessment framework as the standard for the evaluation of transport infrastructure projects. The guidelines in this framework are based on the principles of social cost benefit analysis, and cover all economic and societal effects relevant to transport infrastructure. In recent years structuring the pros and cons of an investment decision by performing a cost-benefit analysis following the OEI-guidelines has become unavoidable for infrastructure planners. Moreover, basic principles in the OEI-guidelines have been adapted by other Ministries, to be used in the appraisal of any decision on a project that is considered of national importance. Since 2005, the original OEI-assessment framework has been updated and extended with a series of seven Appendices. The Appendix on Safety Effects will complete this series of Appendices with methods and guidelines on the evaluation of safety effects. Following the OEI-guidelines, all potentially relevant project effects must be taken into account, including the relevant effects on safety. The Appendix on Safety Effects discusses the safety effects which are most relevant in the evaluation of transport infrastructure projects. Three main fields of safety are identified: traffic safety; societal safety (transport and storage of hazardous goods); and personal safety (safety of the individual in transport systems). For these three main fields, methods for measuring and valuation of safety effects are defined, including the presentation of effects in a concluding scheme. The Appendix aims at measurement and valuation: to measure an effect without a market price like safety in its own units, and in a second step, if possible, assign an economic value to the effect. If certain situations prove this impossible, at minimum a qualitative approach is required by describing the possible effects in words. The first note is that the method of cost-benefit analysis puts a high standard on the quantitative quality of the data used. The evaluation of safety effects will have to focus on changes of the safety level. In other words: the changed accident or incident risk, resulting from the project. To be able to assign an economic value to this change of risk, it is necessary that some minimum of quantitative measure exists. If the risk is unknown, or fluctuating, is may be less useful to assign a monetary value to the effect. For the covering abstract see ITRD E137145.