Buildings, Tunnels & Fire Safety

What we work on

• Wind comfort around buildings and pedestrian-level flow
• Wind loading on tall buildings and stack plume dispersion
• Ventilation design for road and metro tunnels
• Tunnel fire: smoke control, critical velocity and evacuation time
• Smoke extraction in malls, stadiums, atria and metro stations
• Layout and capacity verification of jet fans and pressurisation systems

Typical problems

Here, analysis is rarely a performance improvement exercise — it is usually a life safety verification. The question is not "how efficient" but "can people get out before the smoke layer descends".

Tunnel ventilation below the critical velocity lets smoke travel back against the airflow (backlayering) and blocks the escape route. In large enclosures the height of the smoke layer directly sets the time available for evacuation. At urban scale, wind governs pedestrian comfort and the build-up of pollutants around buildings.

How we work

The fire scenario, the heat release rate (HRR) curve and the acceptance criteria are agreed in writing up front, together with the standard the work will be judged against. Results are reported against visibility distance, smoke layer height and temperature criteria — not as a single colourful picture.

Evacuation time and smoke development are assessed together; looked at separately, either one misleads.