Fans are mechanical units designed for air transportation in the ducts, direct air supply or air exhaust from the premises for ventilation and pressurization applications. Air is moved due to the pressure drop between the fan inlet and outlet vent. Fans are classified according to requirement as normal exhaust fans, Fresh Air Fans, Fire Rated Fans, Pressurization Fans etc in commercial and Industrial Applications. Axial and centrifugal forms of Fans are available. Application for ventilation fans are mainly for Kitchen , Toilet, Car parking Ventilation, etc.