The worst case accident scenario and personnel protection: editorial

A brief editorial discusses recent US Department of Energy Advisory Panel on Accelerator Radiation Safety (APARS) reports which focused on the need for beam shutoff instruments in accidents involving the accelerated beam and the reliability of these instruments. It is concluded that in the absence of the ability to quantify the reliability of personal safety beam shutoff equipment, a limit of reliance on its use should be established. Accelerator shield design should protect both against the worst case accident to some limit as 0.1 Sv per hour in areas potentially occupied by radiation workers and to a much lower level in areas that might be accessible to the general public, as well as against normal operating conditions. (UK)