Abstract: An apparatus for generating an aerosol is provided which includes an atomizing chamber, an aerating wheel and an annular bacteria filter each of which must be sterilized in an autoclave or sterilizer, connected into a modular unit and releasably disposed of through a plug connection on the outer side of the housing. The air supply openings formed in the wall of the aerating wheel chamber, which serve to establish communication between the annular filter chamber and the aerating wheel chamber, may be reduced in a stepless manner by a slidable closure ring. By this regulation of the air supply, the mechanism can also be used for respiration.