FAN FILTER UNIT

PROBLEM TO BE SOLVED: To provide a fan filter unit which has a simplified configuration and in which a prefilter is attached so that the fan filter unit can be installed at a place where space is extremely scarce.SOLUTION: A configuration of a filter fixation guide 12 is configured by a top surface 13 and a side surface 14 forming an L-shaped cross section, and a bottom of the side surface 14 has a plurality of claws 15 protruding in the direction opposite from the top surface 13. Also, a second claw 17 is provided at a short side part 16, which is orthogonal from both ends of the side surface 14 and fixed, and at a bottom of the short side part 16 in this configuration. With this configuration, the thickness of a prefilter 11 and the height of the side surface 14 can be made to be equal, so that dimension in a thickness direction of a product is suppressed to the necessary minimum in a fan filter unit. Therefore, this is extremely useful as the fan filter unit which can be installed at a place where space is extremely scarce.