HNTB tunnel ventilation practice is one of the largest and most experienced team of experts in the industry. Tunnel infrastructure projects require a successful incorporation of ventilation and fire life safety systems ensuring comfortable and safe operations for all users. HNTB brings decades of experience to help identify and execute solutions that balance stakeholder interests and provide benefit to the owner and community.

Featured Tunnel Ventilation Projects

SR99 Tunnel Project

Designed to enhance safety and emergency vehicle access, the SR99 Tunnel features a two-level roadway tunnel to replace the earthquake damaged Alaskan Way Viaduct. At 57.5 feet in diameter and nearly 2 miles long, the tunnel in downtown Seattle is the world’s second-largest soft ground, machine-bored tunnel featuring state-of- the-art ventilation, fire detection and suppression systems designed by the HTNB Ventilation and Fire Life Safety Team. Analysis, represented by the image at left, determined ventilation operations to effectively mitigate carbon emissions during normal and congested tunnel operations.

Boston South Station Expansion

The $37 million South Station Expansion (SSX) project is part of the vision for the New England High-Speed and Intercity Rail Network. Under the direction of MassDOT’s Office of Transportation Planning, and in cooperation with the Federal Railroad Administration, HNTB completed all Preliminary engineering for the expansion of Boston’s South Station and development of rail vehicle layover facilities; including fire life safety analysis for proposed and existing facilities. Analyses performed by the HTNB Tunnel Ventilation and Fire Life Safety Team also helped guide diesel locomotive operating protocols to optimize occupant safety and comfort and meet regulatory requirements.

Tunnel Ventilation Experts

Ana Maria Ruiz Jimenez, Ph.D.

Principal Engineer, National Tunnel Practice

Sean Cassady

Principal Engineer

Bernd Hagenah

Principal Engineer, Tunnel Ventilation

Jesse Harder

Engineering Department Manager

Tunnel Ventilation News and Insights