The invention relates to a method for cleaning at least one optical component of at least one irradiation system comprising a vacuum chamber which contains at least one radiation source generating, in particular, far ultraviolet radiation and/or soft x-rays of which the rays are guided through said optical component and onto a workpiece. The optical component is at least partially soiled with an inorganic substance introduced by the radiation source. In said method, at least one reagent (124) substantially translucent or transparent to the rays (118) is added through a supply system (126), depending on the prevailing reaction conditions. The reagent chemically reacts with the soiling deposits (128) to remove them from the optical component (110).