Method and device for providing a zone of clean air at an operation area and use of said device

A device 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 in a functional position provided 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,
• the air treatment device has at least one air inlet which is provided for receiving or taking in air from upper parts of the operation premises,
• a filter device is provided in the air treatment device in order to filter air for providing clean air which shall define the zone of clean air,
• a device for cooling air to a lower temperature than the temperature of the air in the operation premises is provided in the air treatment device 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 a device is provided in the air treatment device in order to emit or discharge laminar flows of clean air which shall define the zone of clean air in and around the operation area.