Radiological Protection Control at a Cyclotron Facility

摘要

High energy cyclotrons in use by several decades for the production of radionuclides in the diagnosisof diseases have been applied, particularly to supply the short-lived products to nuclear medicine services. Thecyclotrons operate at relatively high beam currents which result in high dose rates in the vaults and there ispotential risk of acute exposure of personnel. The cyclotron staff was identified among the higher exposuregroups in the Instituto de Pesquisas Energéticas e Nucleares – IPEN – CNEN/SP. The radiological protectionstaff has established a radiological protection program whose purpose is providing an adequate occupationalworker protection system in agreement to national and international radiological protection standards. The goalof this paper is to review the characteristics of unusual events occurred in the workplaces at cyclotron facilityduring the year of 2007. In addition, another objective is also to relate the main causes of unusual eventsoccurred in the workplaces that resulted some worker irradiation or workstation contamination. The data analysisincluded the radiological protection records and reports examination, provided by radiation protectionsupervisor, complemented by interviews with radiation protection technician and workers involved in theprocesses. It was verified that in the period of study occurred nine events. Improved technology and dosimetrysystems, the use of dose mapping techniques, innovative approaches to task analysis and the application ofmanagement skills to the planning of maintenance work have all contributed to this success. A major gain hasbeen made but continues procedures reviews to cyclotron group are recommended according to the ALARAprogram.