Smoke and heat ventilation systems
Smoke and heat extraction systems (RWA systems) are used to ventilate smoke and heat from a building in the event of a fire. These systems (commonly used in locations such as parking garages) are automatically activated and extract smoke and heat mechanically using fans. In addition, fresh air is supplied naturally to ensure proper ventilation.
The ventilation system is designed to:
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Ensure access to the fire source (by creating a smoke-free pathway) to allow the fire brigade to operate efficiently.
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Prevent the spread of smoke to minimize smoke damage to the building.
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Remove heat to reduce post-fire damage to the building.
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Create and maintain a pleasant air quality in the building (CO).
Operating Principle of the Ventilation System
The ventilation system ensures optimal air circulation in the garage and consists of two components:
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Daily ventilation combined with CO/NO₂ ventilation in case of elevated CO/NO₂ emissions. When vehicles circulate in an enclosed parking garage, the CO/NO₂ levels naturally rise. The system ensures optimal air quality throughout the entire garage, including all corners. A dedicated CO/NO₂ detection system is therefore essential.
The ventilation is linked to CO/NO₂ detection using CO detectors and NO₂ detectors placed at height. When CO/NO₂ levels reach the highest threshold (emergency level 120 ppm), the system triggers an alarm via double-text warning signs.
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Controlled Smoke and Heat Extraction (RWA) in the event of a fire in the parking garage. In this case, the ventilation system ensures that the required air volume, as defined by the applicable standards, is directed over the smoke control opening(s) with an air velocity of at least 1.3 m/s. Only the jet fans strictly necessary for smoke extraction will be activated.
Smoke and heat extraction will be initiated according to a predefined scenario, depending on the RWA zone in which the fire is detected. A designated smoke detection system is essential in this setup.
Benefits
- Reduction of structural damage to the building above the fire source, thanks to the significant cooling effect of high airflows.
- Guaranteed safe evacuation of individuals.
- Continued accessibility to the fire source for emergency and rescue services.
- No air duct system required, resulting in a minimal loss of space.
- Thanks to the optimal use of automatic smoke curtains, the building maintains an open character during daily use.
- No risk of backdraft due to air supply.
- Improved ventilation in all parts and corners of parking garages due to the induction effect of jet fans.
