Alternate Method for Calibration of PRDs by Means of Gamma Radiation Emitted by Radionuclides
- Science and Technology of Nuclear Installations : 1-8
Résumé
adioactive sources have many beneficial uses across various socioeconomic sectors, but these sources pose safety and security risks. The detection and measurement of ionizing radiation constitute an important pillar not only to ensure radioprotection but above all to prevent illicit trafficking of radioactive materials. However, to guarantee the reliability of data from measuring equipment, these devices should be subjected to periodic calibration. The aim of our study is to undertake alternative calibration of radiation survey meters for calibration factor determination by means of gamma radiation emitted by the 137Cs radionuclide. To do that, calibration equipment has been designed and fully locally set up, and then calibration protocols and procedures have been established. Thirteen (13) survey meters were locally calibrated, and for evaluation of the performance of our designed calibration system, four (04) of them were sent to Ghana Secondary Standard Dosimetry Laboratory (SSDL) for calibration factor comparison purposes. For each survey meter, four (04) series of measurements have been carried out. The results showed calibration factors varying from 1.02 ± 0.10 to 2.24 ± 0.12. The designed calibration tool demonstrates good stability, with a coefficient of variation less than 05%. In addition, according to the statistical indicators criteria, all calibration factors below 1.50 were consistent with SSDL results, whereas the only calibration factor above this value was not. Therefore, the designed calibration tool, together with the calibration protocol and procedures, complies with ISO 4037-3:2019 requirements.
Mots-clés
ambient equivalent dose, calibration factor, conventional true value, radionuclide, survey meter