For the disinfection of a room a method and a device are proposed by which aqueous biocides with polymer containing active substances are discharged in the form of mist with a mean particle size of less than 10 µm into a room by means of ultrasound technology. To be able to discharge the mist gently into the room in a way that saves energy it is proposed that the aqueous polymer containing biocide is firstly atomized on an ultrasound membrane after which the atomized aqueous polymer containing biocide is discharged into the room by at least one fan with air as carrier medium.
