Consulting, expert opinion and research

We provide professional consultancy services in all relevant aspects on tunnel ventilation, aerodynamic, climate, safety and risk analysis, tunnel equipment, and pollution dispersion. We prepare expert opinions in these areas on behalf of constructors and public authorities. We draw on our long-term experience of more than 1000 international projects and the continuous engagement in research and development.

Research and development

New or adapted norms and guidelines lead to changing requirements for tunnel constructions. Changes of the usage requirements can lead to new performance requirements. With the check of the functional and safety requirements of existing tunnels by HBI, the safety level is determined and the need for action and the measures to be realized are demonstrated.

Safety check​​​​​​


Lötschberg base tunnel

Ventilation and safety concept


Young Dong railway tunnel

Ventilation and risk control


Tunnel Groene Hart, Dordtsche Kil and Rotterdam Noordrand

Efficiency of the emergency ventilation


Stuttgart city railway: U12 Hallschlag-Münster

Safety and ventilation concept


Augsburg mobility hub

Safety and ventilation concept


Tunnel Rheinufer Düsseldorf

Smoke extraction and keeping smoke-free


City Tunnel Freiburg

Technical safety risk analysis


Tunnel Böhämmer

Safety analysis


Arlberg Street Tunnel

Expert opinion on tunnel safety


Gallery of Dormagen-Horrem

Risk-based safety evaluation