MODIFICATION OF A MEDICAL LINAC TO A POLYMER IRRADIATION FACILITY

A linear accelerator for X-ray therapy has been modified to generate a 5 MeV pulsed electron beam. The main objective is to irradiate polyme ric materials in open air in order to alter their chemical and mechani cal properties. To meet the radiation protection standards a shielding has been built round the target. Safety is guaranteed by a fail-safe secured programmable logic controller (PLC) monitored by a personal co mputer. The accelerator can be monitored and controlled by a graphics oriented and menu driven program running on the personal computer. In addition, a control panel has been designed and built to show warning signals and to set various linac parameters. A description of the acce lerator modification and of the new control system is presented.