Dose response of the environmental OSL dosimeter to the X ray 80 kV exposure

OSL dosimeter as a passive radiation measuring dosimeter can be an option to replace radiation measurement instrument containing electronic circuit. In this study, dose response on environmental OSL (optically stimulated luminescence) dosimeters to industrial and medical at tube potential 80 kV X ray exposure and their linearity were tested. The effect of fading on reading repeatability after the OSL dosimeters stored were examined. Forty-eight OSL dosimeters were annealed and read to ensure that the dose information was reset to zero. Then they were packed using Al foil to prevent light exposure. The dosimeters are divided into 2 groups, namely 24 dosimeters for irradiation of industrial X ray and the rest for medical X ray. Each of them is divided into 6 groups consisting of 4 dosimeters each. The five groups were irradiated at 0.5 mSv, 1 mSv, 2.5 mSv, 5 mSv and 10 mSv at a distance of 200 cm with an additional filter of 0.59 mm Cu for industrial X ray and 0.3 mm Cu for medical X ray. While the rest consisting of 8 dosimeters were as control dosimeters. All dosimeters were read using the OSL microStar Reader. The result shows that the ratio of the measured dose to the exposure dose on industrial X ray is ≥0.89 for≥2.5 mSv exposure. It was different when it compared to the response with 1 mSv and 0.5 mSv exposure that the ratio is ≤0.61. Moreover, the smaller the dose of exposure, the deviation of the measured dose to the exposure dose is greater. Meanwhile, ratio measured dose to exposure dose in the medical X ray did not show a tendency as in the industrial X-ray exposure. Deviation of the measured dose to exposure dose in medical X ray is ≤22%. The fading effect of OSL dosimeter on the 12th day reading dose on industrial X ray was ≤6% while for medical X-ray showed a fading ≤7% on 14th day. It can be seen that the fading effect on the OSL dosimeter to X ray is relatively small. Linearity curve shows that the correlation between the measured dose to the exposure dose at industrial X-ray is linear with a correlation factor (R2)≥0.999. Meanwhile, linearity on medical X ray indicates R2 value≥0.997. The experiment showed that the relationship between measured dose to exposure dose on industrial and medical at tube potential 80 kV X ray was linier. After 2 weeks stored the fading effect of OSLD was relatively small.