1.1 This specification covers centrifugal and axial fans and blowers with airstream components fabricated of fiber-reinforced thermoset plastics (FRP) for corrosion resistance. Internal structures may include encapsulated metal fastening devices, hubs, and shafts. 1.2 Reinforcing materials other than fibrous glass may be used in the fabrication, provided the fans and blowers produced meet all the requirements of this specification. 1.3 The term “