This week I've invited a guest, that I was looking to talk to for a good while... Dr Ingo Riess from Riess Ingenieur-GmbH is someone I look up to in the field of tunnel fire safety, in which I am very active in the last few years. In this chat, we had the chance to go through the concept of tunnel resiliency and calculate the risk related to the whole road network, rather than just a tunnel on its own. This is such a refreshing concept, in which the goal - maximizing public safety - is well defined, and thanks to that, smart decisions can be made. And these decisions are not always to make the tunnel a bit safer - in some cases, it may be just better to invest in other safety infrastructure. This holistic view opens new pathways and possibilities and makes investments in fire safety really reasonable. I absolutely love it, and it is something I wish we can implement in my own country.  Outside resilience, we also had a good chance to discuss the ventilation and modelling, design fires and some tough choices the engineers have to make when refurbishing tunnels. If you have anything to do with tunnels, this episode is definitely for you. And if you do not, still can be inspiring, as the world of tunnels is one the forefront of applying risk-based concepts in performance-based engineering. Something, that the rest of the world must eventually catch up.Make sure to check Ingo's ResearchGate, where he stores all the magnificent reports we have talked about (and many more we did not).https://www.researchgate.net/profile/Ingo-RiessAlso, give a chance to the Graz  Tunnel Safety and Ventilation conference, which always delivers the best content related to the fire safety of tunnels:https://www.tunnel-graz.at/