Brookhaven Tandem Facility Radiation Safety System

A system of personnel protection has been developed for the Brookhaven Tandem Accelerator Facility which imposes a minimum of inconvenience upon the experimentalist. The amount of required security (and attendant restriction on personnel) is kept commensurate with the potential radiation exposure and does not seriously interfere with nonhazardous modes of operation. Radiation areas are divided into zones which permit selective access into low-risk areas. Personnel are excluded from radiation areas on a zone-by-zone basis as the radiation intensity rises. A perimeter consisting of zones and additional barriers surrounding the entire radiation area provides secondary protection against unauthorized access regardless of radiation levels. Violation of the perimeter causes the ion beam to be intercepted before it enters the accelerator. Violation of a high-radiation zone causes shutdown of the accelerator.