A system comprising: - a radiation body comprising a radiation exit window, wherein the radiation body is configured to receive radiation that at least comprises UV radiation, and wherein the radiation exit window is capable of allowing at least part of the radiation to pass to the exterior of the radiation body; - at least one radiation source configured to provide the radiation; - at least one detector configured to detect an internal radiation intensity in the radiation body; and - a controller arrangement, functionally coupled to the at least one radiation source and the at least one detector, configured to set a normal state of the at least one radiation source in which the at least one radiation source provides the radiation with an intensity at an operational level as a default, and to set an adapted state of the at least one radiation source in which the at least one radiation source provides the radiation with an intensity at an adapted level that is reduced relative to the operational level after occurrence of a disturbance incident involving a change of the internal radiation intensity detected by the at least one detector characterised in that the system is configured to apply a safety algorithm after occurrence of a disturbance incident that involves setting an evaluation state of the at least one radiation source during evaluation periods separated by evaluation intervals (E 1, E 2), in which evaluation state the at least one radiation source provides the radiation with an intensity at an evaluation level that is increased relative to the adapted level, and setting the adapted state of the at least one radiation source outside of the evaluation periods, and that involves determining a value of the internal radiation intensity during the evaluation periods, and to abort the safety algorithm and to restore the normal state of the at least one radiation source when the value of the internal radiation intensity is inside an evaluation reference range of values. - a radiation body comprising a radiation exit window, wherein the radiation body is configured to receive radiation that at least comprises UV radiation, and wherein the radiation exit window is capable of allowing at least part of the radiation to pass to the exterior of the radiation body; - at least one radiation source configured to provide the radiation; - at least one detector configured to detect an internal radiation intensity in the radiation body; and - a controller arrangement, functionally coupled to the at least one radiation source and the at least one detector, configured to set a normal state of the at least one radiation source in which the at least one radiation source provides the radiation with an intensity at an operational level as a default, and to set an adapted state of the at least one radiation source in which the at least one radiation source provides the radiation with an intensity at an adapted level that is reduced relative to the operational level after occurrence of a disturbance incident involving a change of the internal radiation intensity detected by the at least one detector characterised in that the system is configured to apply a safety algorithm after occurrence of a disturbance incident that involves setting an evaluation state of the at least one radiation source during evaluation periods separated by evaluation intervals (E 1, E 2), in which evaluation state the at least one radiation source provides the radiation with an intensity at an evaluation level that is increased relative to the adapted level, and setting the adapted state of the at least one radiation source outside of the evaluation periods, and that involves determining a value of the internal radiation intensity during the evaluation periods, and to abort the safety algorithm and to restore the normal state of the at least one radiation source when the value of the internal radiation intensity is inside an evaluation reference range of values. configured to set a normal state of the at least one radiation source in which the at least one radiation source provides the radiation with an intensity at an operational level as a default, and to set an adapted state of the at least one radiation source in which the at least one radiation source provides the radiation with an intensity at an adapted level that is reduced relative to the operational level after occurrence of a disturbance incident involving a change of the internal radiation intensity detected by the at least one detector characterised in that the system is configured to apply a safety algorithm after occurrence of a disturbance incident that involves setting an evaluation state of the at least one radiation source during evaluation periods separated by evaluation intervals (E 1, E 2), in which evaluation state the at least one radiation source provides the radiation with an intensity at an evaluation level that is increased relative to the adapted level, and setting the adapted state of the at least one radiation source outside of the evaluation periods, and that involves determining a value of the internal radiation intensity during the evaluation periods, and to abort the safety algorithm and to restore the normal state of the at least one radiation source when the value of the internal radiation intensity is inside an evaluation reference range of values.