Ionizing radiation from operation of particle accelerators and protection therefrom

An analysis was made of accelerated proton and electron interactions showing that a radiation field exists in the immediate area of accelerators consisting of photons and neutrons. The contribution of the respective components depends on the accelerator specifications, such as the type and energy of accelerated particles, particle density in the beam, the type of shielding, etc. Significant doses may only be expected within limited spaces near the accelerator in case of a random beam release. Nuclear reactions induce radioactivity in targets, collimators, deflectors and their vicinity. Remote control systems are therefore used for handling these components and their repairs. Basic specifications are given for the accelerator shielding design. The exposure of accelerator operators is low; 85% of personnel receive a monthly dose lower than 0.6 mJkg-1. With a correctly designed shielding the environmental impact of accelerator operation is practically nonmeasurable. (Ha)