G. Khoury and &. , Global approach to tunnel safety (part of Workpackage 5 -Evaluation of safety levels and upgrading of existing tunnels -D56) available at http://www.uptun.net/, deliverable of UPTUN ? Upgrading existing tunnels for fire safety -Final Technical Report, 2006.

F. Amberg, Harmonising safety and security research for underground infrastructure in Europe, Proceedings of the ISTSS 2008, pp.12-14, 2008.

R. Leucker, D.4.2.2 Report for Service Life Cost Model, 2006.

J. A. Volpe, FTA Transit Security Design Considerations. Final Report available at http://transitsafety .fta.dot.gov/security, 2004.

A. Venetsanos, Initial Guidance for Using Hydrogen in Confined Spaces - Results from InsHyde, 2009.