ABSTRACT
REGULATIONS governing X-ray irradiators are basically the same as those for electron beam irradiators because both technologies have at the heart
of their operations high-power electron beam accelerators. As is the case for electron beam irradiators, X-ray irradiators are regulated by the state in which the irradiator is located rather than by a federal agency. Other than controls the OSHA or the EPA may apply, the individual state has responsibility for overseeing all radiation safety-related aspects of the operation. Criteria for designing the radiation shield follow the same guidelines as those for electron beam irradiators [85]. In both cases, shielding of X-rays is the key factor that needs to be taken into account in design of the shield. A conversion target is used to produce X-rays in X-ray irradiators, while in electron beam irradiators, the X-rays are generated from the irradiated material and from scattering of electrons in surrounding materials. The walls and ceiling of the cell must be sufficiently thick to keep X-rays and scattered electrons from escaping the irradiation room. A maze or similar structure is used to prevent leakage of radiation from entrances and exits to the cell. Radiation safety systems, equipment for removing ozone from the cell and procedures for training personnel are similar to those employed at electron beam facilities.
