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A wind deflector for a smoke ventilation system can sometimes be a legal requirement. It helps to dissipate smoke even when wind conditions aren't ideal. Therefore, it reduces the risk of occupants of the building inhaling smoke in the event of a fire.

The wind detector allows you to comply with aerodynamic smoke ventilation requirements or geometrical area requirements.


  • Geometrical opening area, Av [m²]
  • Aerodynamic area with wind deflector (KWU) , Aa [m²]


  • The KAS smoke ventilation window, without a wind deflector, is used when the only legal requirement is geometrical area
  • The KWU wind deflector should be used when an aerodynamic free area is legally required. This may depend on the application and the local legislation.
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