Abstract: A pre-conditioned air (PCA-) device is provided for conditioning air in an interior of a cabin of a parked aircraft (12) and for sanitizing an air and surfaces in the interior of the cabin. The PCA-device includes an air pre-conditioning (PCA-) unit (1) for forming a stream of pre-conditioned air (5c); a photo catalytic oxidation unit (2) for forming reactive oxygen species (ROS) in the stream of pre-conditioned air including dry hydrogen peroxide at a concentration below 1 ppm, thus forming a stream of peroxided air (5p); and an air distribution ducting (3) for injecting the peroxided air (5p) into an internal air circulation duct of an aircraft, wherein the photo catalytic oxidation unit (2) includes a source of ultraviolet (UV-) light (2uv) configured for irradiating a UV-volume with UV-light; and a catalyst (2c) located within the UV-volume and intersecting the stream of pre-conditioned air.