Principles of Smoke Ventilation

What is a smoke control system?

An effective smoke control system ensures smoke can be vented from escape routes within high-rise buildings including corridors, lobbies and especially staircases. Designed to operate on a floor by floor basis, the detection of smoke within any of the protected areas triggers the smoke control system which automatically opens smoke doors and Automatic Opening Vents (AOVs) to allow smoke to be removed from the affected area and keep escape routes clear.

Smoke ventilation allows the creation of a smoke free layer by removing smoke. This improves the conditions for safe escape and permits the fire to be fought in its early stages. Smoke can be vented naturally or mechanically. Natural smoke ventilation uses the inherent buoyancy of hot smoke and airflow dynamics of smoke and air to remove smoke using the building façade.

A mechanical system uses powered elements such as fans to force the movement of smoke and allow it to escape through dampers, grills and vents. Mechanical systems generally utilise a smoke shaft and are useful where space is at a premium and/or where natural airflow is insufficient to achieve the required performance.

With Smoke Ventilation

With Smoke Ventilation


What happens if there is a smoke ventilation system?

1. ln the event of a fire, actuators open high level smoke vents and low level fresh air inlet vents.

2. This allows cool air into the building, forcing the hot air and smoke out via the roof, providing a smoke free layer for safe escape.

3. The smoke free layer allows safe access for the fire to be fought and extinguished.

Without Smoke Ventilation

Without Smoke Ventilation

What happens if there is no means of smoke ventilation?


1. In an unventilated room, smoke will rise directly to the ceiling.

2. The smoke will begin to fill the space available moving laterally instead of vertically.

3. Convection of the smoke will cause it to be drawn back down to low level reducing visibility and the chances of a safe escape.

4. Temperatures will continue to rise causing the potential flash over and collapse of the building.

Smoke Control Systems and AOV/Smoke Vent Actuators.

Our products are tested in accordance with the relevant EN12101 harmonised suite of standards for smoke control compliance and designed in accordance with BS7346-8 Code of Practice for planning, design, installation, commissioning and maintenance of smoke control systems.

Case Studies.

View our wide range of completed smoke control projects from across the world.


Online Video - Mechanical Smoke Ventilation

Mechanical Smoke Ventilation: Successfully Keeping the Escape Route Free of Smoke.

Watch Video

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