A device for dry ice treatment and, in particular, for dry ice cleaning of surfaces, wherein the device comprises: - a dry ice source for supplying dry ice, in particular in the form of dry ice particles; - a mixing unit fluidly connected or connectable to the dry ice source; and - a compressed air source fluidly connected or connectable to the mixing unit for supplying compressed air to the mixing unit, in which a dry ice particle-compressed air mixture is generated with the supplied compressed air and the supplied dry ice, which can be applied to the surface to be treated for dry ice treatment and, in particular, for dry ice cleaning, wherein the compressed air source is assigned a conditioning unit for conditioning the compressed air supplied to the mixing unit as required or depending on the application, namely with regard to the size and concentration of solid particles still comprised in the supplied compressed air, with regard to the pressure dew point and the moisture content of the supplied compressed air, and with regard to a residual amount of oil aerosols and hydrocarbons that may still be comprised in the supplied compressed air, characterised in that the conditioning unit can be operated alternatively in one of the following operating states: - in a first operating state in which the compressed air supplied by the compressed air source may still comprise solid particles having a size greater than 5 μm; or - in a second operating state, in which the compressed air supplied by the compressed air source may still comprise solid particles having a size of up to a maximum of 5 μm according to ISO 8573-1:2010, and that the conditioning unit comprises a filter device, wherein the filter device comprises at least one pre-filter and at least one post-filter, wherein depending on the selected operating state of the conditioning unit, selectively or as required, at least the at least one post-filter can be switched on or off for compressed air conditioning. - a dry ice source for supplying dry ice, in particular in the form of dry ice particles; - a mixing unit fluidly connected or connectable to the dry ice source; and - a compressed air source fluidly connected or connectable to the mixing unit for supplying compressed air to the mixing unit, in which a dry ice particle-compressed air mixture is generated with the supplied compressed air and the supplied dry ice, which can be applied to the surface to be treated for dry ice treatment and, in particular, for dry ice cleaning, wherein the compressed air source is assigned a conditioning unit for conditioning the compressed air supplied to the mixing unit as required or depending on the application, namely with regard to the size and concentration of solid particles still comprised in the supplied compressed air, with regard to the pressure dew point and the moisture content of the supplied compressed air, and with regard to a residual amount of oil aerosols and hydrocarbons that may still be comprised in the supplied compressed air, characterised in that the conditioning unit can be operated alternatively in one of the following operating states: - in a first operating state in which the compressed air supplied by the compressed air source may still comprise solid particles having a size greater than 5 μm; or - in a second operating state, in which the compressed air supplied by the compressed air source may still comprise solid particles having a size of up to a maximum of 5 μm according to ISO 8573-1:2010, - in a first operating state in which the compressed air supplied by the compressed air source may still comprise solid particles having a size greater than 5 μm; or - in a second operating state, in which the compressed air supplied by the compressed air source may still comprise solid particles having a size of up to a maximum of 5 μm according to ISO 8573-1:2010, and that the conditioning unit comprises a filter device, wherein the filter device comprises at least one pre-filter and at least one post-filter, wherein depending on the selected operating state of the conditioning unit, selectively or as required, at least the at least one post-filter can be switched on or off for compressed air conditioning.