MEA Computer Controlled Personal Access System

The computer based personal access system (PAS) overlooks eight separate entrances of the MEA linac and experimental areas, it eliminates the interference of the safety staff and and demands limited discipline of the users. The PAS is roughly based on: 1. Machine conditions. The status of magnets, beam stoppers, Etc., controls the access to the rooms by means of conventional electronic door control-units. 2. Room conditions. The result of the automatic measurement of the levels of the gamma radiation or the ozone contents of the air dominates the door controls. 3. Personal registration, based on the use of one lock-cabin per entrance and linked to a central computer. On permitted passage through the lock-cabin the computer authorizes and registers each passerby individually. In addition to keeping book of the total number of people present in the rooms an independent electromechanical device provides authorization at each lock-cabin. A weighing system guarantees passage of only one person at the time. Safe access of either the beam or a person is secured by this purely instrumental system.