Quantification of radio-photoluminescence glass dosimeter with different radionuclide beams

MSc (Applied Radiation Science), North-West University, Mafikeng CampusHuman beings, animals, and the environment need to be protected against natural radiation sources and man-made radioactive materials. Radiation detectors are pivotal instruments in detecting radiation, be it personal exposure or environmental exposure. Now, valid calibrated radiation detectors are even more important to show accurate the response of the instruments to radiation. Thus, this information can be used to take necessary measures that should be implemented in case of high exposure risk detected to reduce radiation exposure levels to as low as reasonably achievable (ALARA). Radio-photoluminescence glass dosimeters (RPLGDs) are part of the luminescence family of dosimeters just like the Thermoluminescence dosimeters (TLDs). For years now, Panasonic thermoluminescence dosimeters have been used for both personal monitoring and environmental monitoring in South Africa and have limitations. TLDs are used to monitor different types of radiations. The quantity which is measured when TLDs are used for personal monitoring is personal dose equivalent, and for environmental monitoring is ambient dose. Thus, the same techniques as TLDs can be explored with RPLGDs since they both use the thermoluminescence phenomenon. Three radiation sources (i.e. Cs-137, Co-60 & Am-241) were used to characterize the response of RPLGDs when exposed to different radiation doses. The ability of RPLGDs to be read more than once without losing original signal was studied. RPLGDs were investigated for their ability to measure both personal and environmental monitoring. Substitution method was used to determine the reference measurements on all radiation source setups. Reference detectors were positioned in the radiation beam to measure prescribed doses at the calculated time obtained from the dose rate and prescribed doses. Three radiation detectors (i.e. cylindrical ionization chamber, farmer ionization chamber and RPLGDs) were used. Two ionization chambers were used as reference detectors and RPLGDs as the unit under test (UUT) on each radiation source setup. Dose rates were used to determine the time of the prescribed radiation doses. RPLGDs were exposed to the same time as the reference detectors to accumulate radiation signal which was corrected to determine the absorbed dose. All the corrections that affected the response of UUT were implemented on the final readings of the RPLGDs to compare with the prescribed dose.Master