There are many uses for the continuous flow of air or gas that industrial fans generate, including combustion, ventilation, aeration, particulate transport, exhaust, cooling, air-cleaning and drying. The industries served include electrical power production, pollution control, metal manufacturing and processing, cement production, mining, petrochemical, food processing, cryogenics and clean room. Most industrial fans may be categorized into general types such as centrifugal fans, axial fans, ventilation fans, exhaust fans, compact fans and blower fans.