SIAV & VTB Series are the only dry positive displacement blowers capable of attaining 28" Hg (93% vacuum). Our vacuum blowers SIAVVTB are also available in Atex category 2 version, on request (Atex II 2 GD c IIB T3 160°C) Applications S.I.A.V. series blowers are engineered primarily for vacuum applications. They can alternatively be used for pressure unloading. Standard applications are: Vacuum trucks (industrial, septic, municipal, etc.); Fly ash vacuum pneumatic conveying Evaporation, Centralized plant vacuum Soil remediation