FFU is a combination of a fan and a filter, and can also be called a filter device with a fan. The FFU is usually installed at the air supply end of the clean room and is typically placed on a hoisted "dry" gasket seal keel frame. The upper part of the FFU is a fan module, and the lower part is a filter. Depending on the cleanliness requirements, the filter can be a different grade of high efficiency (HEPA) or ultra high efficiency (ULPA) filter to provide clean air to the clean room. In addition to overcoming the resistance of the high-efficiency filter in the lower part of the FFU, the fan module must overcome the resistance of all the passage parts of the entire circulating air to maintain the set operating wind speed. The FFU system has the characteristics of simple design and construction, flexible wind speed adjustment and easy change of clean area, so it has become one of the popular system forms of industrial clean room.
The FFU unit is designed to be flexible and easy to use with a dedicated ceiling frame and other suitable skeletons. When the filter adopts a knife-edge frame, the unit can also be used for the tank seal ceiling frame. According to the design specifications, it can easily fit any ceiling frame to meet the cleanliness level. The outer frame can be made of aluminum or stainless steel, each with its own characteristics. With this unit, high quality air can be delivered to the clean room and the air is well circulated. It is suitable for manufacturers of semiconductors, electronics, flat panel displays and disk drives, as well as optical, bio-industry and other places where strict control of air pollution is required.