Activation of medical accelerator components and radioactive waste classification based on low beam energy model Clinac 2300
Magdalena Długosz‐Lisiecka, Michał Biegała, Teresa Jakubowska
Abstract
The medical linear accelerator, used in Nicolaus Copernicus Hospital in Lodz is integrated system used for photonuclear therapy. The accelerator shows presence of radioactive impurities produced by activation process, by the beam interactions take place and result in residual radioactivity that lasts even after operation and dismantling of the accelerator. The radioactive material management, after disposing or replacing components of the medical accelerator, presents some technical challenges, due to the lack of the clear standards for radioactive waste management in Poland. In practice, most radioactive wastes were stored within the institution or by the manufacturer. After 10 years of operating the medical linear accelerator, the majority of the resulting radioactive waste has been dismantled and each eliminated part has been controlled by verifying the contact dose rates for the pilot analysis with the objective to establish a radioactive waste classification procedure for low beam energy below 35 MeV accelerators. Six accelerator structural elements with elevated surface dose rate values were submitted to radiometric analysis for proper analysis of materials as radioactive wastes. Identification of radionuclide impurities in the construction of an accelerator is the only possible method of proper classification of activated materials, due to the safety assessment of the storage facility.