[297010] Artigo – CBMRI – Congresso Brasileiro de Metrologia das Radiações Ionizantes

Resumo:  This study contributes to the efforts aimed at obtaining licensing for the Gamma Calibration Laboratory at the Technology Center of the Brazilian Army (LCG/CTEx) from the Testing and Calibration Services Evaluation Committee (in Portuguese: Comitê De Avaliação de Serviços de Ensaio e Calibração – CASEC) of the Institute of Radioprotection and Dosimetry (in Portuguese: Instituto de Radioproteção e Dosimetria – IRD) under the National Commission of Nuclear Energy (CNEN). As a certified calibration laboratory, it is equipped to offer services to both the Brazilian army and external customers. As part of this process, the ABNT NBR ISO 4037 standard addresses various aspects that need to be characterized for this laboratory, one of which is the contribution of scattered radiation in the calibration measurements conducted there. This work greatly benefitted from utilizing the Monte Carlo (MC) simulation method to model this laboratory and to determine the dose rates at the work points. The MCNP code calculated the flux in a point detector, which was then converted into the operational quantity ambient dose equivalent 𝐻∗(10)using the conversion factor provided by ICRP 74. Through the simulation, it was possible to identify the shield wall as the primary reflective area causing scattered radiation, but it remains within the limits defined by the standard.