Open Access Library Journal 2018, Volume 5, e4741 ISSN Online: 2333-9721 ISSN Print: 2333-9705 Developing a Methodology for Determining Design and Operating Requirements for Contracting Tunnel Works Nikolaos Vagiokas Enalos PC, Athens, Greece Abstract Directive 2004/54/EC [1] on minimum safety requirements for tunnels in the trans-European road network sets the bases for establishing an accepta- ble safety level for tunnel users across EU member states. Furthermore, many EU member states enforce stricter safety requirements for tunnels in their territory. The lack of a methodology for determining design and op- erating requirements for tunnels leads many times to an expensive over-design for tunnel works and thereafter operation and maintenance, throughout the tunnel lifetime without the expected increase in safety le- vels. In the present paper a methodology has been developed in order to as- sist all parties involved in contracting tunnel works to establish the opti- mum design and operating requirements. The methodology combines re- sults of risk analysis with cost benefit analysis in different time periods throughout the tunnel design life. The results from implementing the aforementioned methodology include the optimum set of design and oper- ating requirements for each tunnel under consideration. Concluding, the necessary contribution of each beneficiary to the funding of the different sets of design and operating requirements for certain time periods throughout tunnel lifetime, is soundly estimated and justified. The proposed methodolo- gy is an excellent tool since it can be used regardless of specific risk acceptance criteria. Subject Areas Transport, Safety Keywords Tunnel Safety, Tunnel Operation, Tunnel Maintenance, Cost Benefit Analysis How to cite this paper: Vagiokas, N. (2018) Developing a Methodology for Determining Design and Operating Requirements for Contracting Tunnel Works. Open Access Library Journal, 5: e4741. https://doi.org/10.4236/oalib.1104741 Received: June 26, 2018 Accepted: July 10, 2018 Published: July 13, 2018 Copyright © 2018 by authors and Open Access Library Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ Open Access DOI: 10.4236/oalib.1104741 Jul. 13, 2018 1 Open Access Library Journal