The purpose of the present invention is to detect and remove causes of microparticles in a room so as to suppress the generation of microparticles having adverse health effects. This air cleaner is provided with a casing 1, a suction inlet 2, a blowing outlet 3, a blower 4, a cleaning means 5, an odor detection means 6, a light detection means 7, a reactive species detection means 8, a control unit 9, etc. The control unit 9 controls the blower 4 on the basis of the concentration of odors, the presence or absence of light, and the presence or absence of reactive species including ions or radicals, and executes an air cleaning capability-boosting operation as needed. Thus substances which would have led to the generation of microparticles that are difficult to detect with a dust detection means 13 or the like can be removed before such microparticles are generated. Hence, the generation of microparticles having adverse health effects can be efficiently suppressed, and the interior of a room can be kept in a clean condition.
