Patent ID: 8066802

Claim:
Method for providing a zone of clean air at an operation area by means of an air treatment device, wherein a lighting device is provided for illuminating the operation area wherein: the air treatment device and the lighting device and/or the operation area are/is brought or have/has been brought to a functional position such that the air treatment device and the lighting device are located above the operation area and between said operation area and the ceiling in the operation premises in which the operation area is situated, air is received or taken in into the air treatment device from upper portions of the operation premises, air is filtered in the air treatment device for providing clean air which shall define the zone of clean air, air is cooled in the air treatment device to a temperature that is lower than the temperature of the air in the operation premises in order to allow clean air which shall define the zone of clean air to have such lower temperature than impure air surrounding the zone of clean air, that said clean air descends slowly downwards towards the operation area, and clean air which shall define the zone of clean air in and around the operation area is emitted or discharged from the air treatment device as laminar flows of clean air.