The report itself is from 2013. I am not sure about the legal subjects but I am sure it is fairly up to date on the technical side. I've got it at the university library, but you can download it at PIARC site if you like.

https://www.piarc.org/en/order-library/19376-en-Risk%20evaluation,%20current%20practice%20for%20risk%20evaluation%20for%20road%20tunnels

Excerpt from their website:

This report is intended to provide discussion on the various established strategies for the evaluation of the results of a risk analysis for the risk assessment of road tunnels.

After a presentation of background information on risk evaluation, the principles of the different approaches, both qualitative and quantitative, are explained and discussed. Evaluation of quantitative approaches for societal risk forms the main focus of this report which considers evaluations against absolute or relative criteria.

Current practice of risk analysis for road tunnels and practical methods specifically applicable for the transport of dangerous goods are presented for a number of different countries.

Finally, the report considers the legal implications of risk analysis.