Adaptation and security validation of an irradiator suitable for use of cesium-137 sources

With the aim of offering a new application for 137Cs sources that were previously used in brachytherapy, we developed an irradiator for TL and OSL dosimeters by adapting a shielded storage container; this irradiator was named SOPHIA. It was assembled from a cubic iron casing, filled with lead, with external dimensions of 25 × 25 × 25 cm3. It has three different drawers with two sample holders suitable for samples or dosimeters with dimensions of up to 2 cm. Dose distribution of the surface of sample holder was obtained with EBT-3 radiochromic film and detectors thermoluminescent CaSO4: Dy. Regarding the security conditions of irradiation, the whole routine procedure for placement and removal of samples was simulated using Monte Carlo code. The equipment presented proper security conditions and the doses received by users during procedures for placement and extraction of the samples are in accordance with international standards