Abstract: An air treatment system comprising a plurality of excimer lamps, said system is arranged such that at least 90% of air flowing through the air treatment system will be exposed, to photons emitted from the excimer lamps, whereby the excimer lamps provides a large emission area in which high energy ultraviolet (UV) photons is provided at low cost. The photons will upon contact with contaminants in the air break down said contaminants through the process of photolysis, which is highly effective at removing different organic compounds, e.g. odours from the air. The system can be designed with different wavelengths, making the system a simple and inexpensive air treatment system both for use in large area industrial applications and for domestic uses.