Tunnel ventilation

Tunnel ventilation is critical for a variety of reasons – for example to ensure an adequate air quality, to control the spread of smoke in case of fire, or to reduce temperatures to acceptable limits.  The function of the ventilation relates to the type of tunnel in question. Vehicular tunnels (road, rail and metro) generally require high air quality during normal operation and smoke control in case of fire, while cable tunnels require cooling, smoke control and a certain amount of air exchange. Mine tunnels and station tunnels also require adequate ventilation for physiological, cooling and smoke control requirements.

A number of alternative tunnel ventilation systems are available, including transverse, semi-transverse and longitudinal. For short tunnels that are 3 km or less in length, longitudinal ventilation systems are generally preferred due to their modest construction cost. Depending on fire risk mitigation and the maintenance of adequate air quality, longitudinal ventilation systems can be installed in much longer tunnels – for example in the proposed 18 km Fehmarnbelt Tunnel connecting Germany to Denmark.

Mosen has extensive experience in all types of tunnel ventilation systems, for both vehicular and non-vehicular tunnels. We have been involved in the design and review of well over 100 tunnel ventilation systems worldwide, and have the full range of capabilities to undertake the full range of required design and commissioning activities.

To download some useful software to estimate the required ventilation capacity for smoke ventilation, please click on this link.

To download some useful software to estimate the critical velocity for smoke control, please click on this link.