Apparatus for exhausting dust (ventilation); Apparatus for exhausting fumes (ventilation); Apparatus for exhausting gases (ventilation); Apparatus for exhausting mists (ventilation); Apparatus for exhausting particles (ventilation); Apparatus for extracting dust (ventilation); Apparatus for extracting fumes (ventilation); Apparatus for extracting gases (ventilation); Apparatus for extracting mists (ventilation); Apparatus for extracting particles (ventilation); Dust extraction installations (ventilation); Dust removing installations for ventilation; Extractor units (ventilation); Extractors (ventilation or air conditioning); Industrial ventilation apparatus; Process ventilation apparatus; Propellers (fans) for ventilation apparatus; Ventilation apparatus