Evacuation provision for safe egress using pressurized vestibules for upgrade of Louis-Hippolyte La Fontaine Tunnel

Providing a safe path of egress for tunnel occupants during an emergency scenario is critical. Especially, smokiness the fire escape route poses safety hazard during emergency evacuations. This paper highlights the benefit of pressurized airlocks in the evacuation safety in the case study of Lafontaine Road tunnel. Smoke ingress is effectively prevented by the airlocks which connect the evacuation corridors to the traffic tunnels of Lafontaine tunnel. Furthermore, the paper discusses relevant design procedures and provisions to set and achieve adequate ventilation criteria for safe egress from the tunnel through the airlocks and evacuation corridor. The performance of the pressurized system is quantified as a function of pressure gradient between the traffic tunnel and the evacuation corridor with varying configurations of number of open exits, leakages, and operational profiles. The challenges and lesson-learned are also discussed in this study.