tunnel fan

Tunnel fans are high-capacity axial or jet fans installed in tunnel portals or intermediate shafts to supply fresh air or extract exhaust and smoke during normal operation or emergencies.

They deliver up to 1,000,000 CFM at static pressures to 10 kPa, ensuring rapid smoke clearance in fire scenarios and maintaining acceptable CO₂ and particulate levels during traffic flow.

Integrated variable frequency drives (VFDs) enable traffic-responsive control, modulating airflow based on tunnel occupancy, pollutant sensors, and fire detection systems to optimize energy use and safety.

Maintenance features include access platforms, vibration-damping supports, and remote condition monitoring. Tunnel fans are critical for regulatory compliance and emergency response in modern underground infrastructure.