The X-ray Ordinance of 1973 defines the legal terms "controlled area" (sec. 15) and "X-ray room" (sec. 16) differently, serving different legal purposes. For the application and interpretation the two terms are to be distinguished. The competence to locate the limits of the "controlled area" lies with the radiation protection officer according to secs. 11, 12, and 15 of the X-Ray Ordinance. He is authorized to enlarge the "controlled area" and to make its limits identical with those of the X-ray room. The State authorities may intervene in this primary competence of the radiation protection officer only in exceptional cases (15 subsec. 4). The competent State authority may ask the radiation protection officer to enlarge a "controlled area" if it seems necessary for the protection of individuals or of the public. However, a general order of the supervisory authority implicating identical definition of "controlled area" and "X-ray room" would be inconsistent with the explicit provisions of the X-ray Ordinance and therefore unlawful.