ABSTRACT
The rising number of new-to-build tunnels and the recent tunnel disasters in European countries force us to evaluate the safety level of tunnels. The Dutch legislation does not contain concrete determination methods to measure and evaluate the safety level. It is in practice negotiated in a decision making process. As the safety level cannot be evaluated directly, it has to be evaluated indirectly by judging the decision making process. A reconstruction of the decision making process on the safety level of the Westerschelde tunnel has been made and its process and content have been evaluated by an especially developed framework [5]. This framework consists of five criteria: completeness of safety measures, recognition of interactions, commitment of parties, use of knowledge, and cost-effectiveness. The scores of the criteria have been summed to result in an overall score for the decision making process on user safety in the Westerschelde tunnel.
