PROBLEM TO BE SOLVED: To solve the problems that it is important to concentratedly expose a ceiling plane and a floor surface to ozone-containing air in order to effectively perform deodorization, sterilization and pest generation prevention by ozone generation, but a conventional diffusion-type device cannot effectively expose a ceiling side and a floor side as the main objects thereof to ozone-containing.SOLUTION: A device includes increasing the effects of deodorization, sterilization, and pest prevention function through ozone by: supplying heated ozone-containing air and cooled ozone-containing air for making a cold retention air layer of a floor part existing inside a room, and a heat retention air layer of a ceiling part； confirming an environmental state allowing stably constructing the upper and lower heat retention air layers； individually supplying ozone-containing air which is set to higher than an existing air temperature at a ceiling side and lower than an existing air temperature at a floor side； and forcibly substituting an existing air layer for an air layer with a high ozone concentration.SELECTED DRAWING: Figure 2
