The Potential Use of Car Windscreens for Post-Accident Dose Reconstruction in the Periphery of Nuclear Installations

Abstract

Cars of a variety of brands are usually parked at a fixed but increasing distance in the periphery of nuclear installations. Herein we focus on the potential use of car windscreens for post-accident dose reconstruction from unplanned nuclear events and natural disasters, also in regard to unexpected events arising during large-scale use of radioactive and nuclear materials. The situation requires identification of analytical techniques that could both readily and reliably be used to assess absorbed dose, sufficient to prompt remedial action where necessary. Samples from three widely used car brands—Honda, Toyota and Proton—are studied in respect of their thermoluminescence (TL) yield. Key TL dosimetric features in the gamma-ray dose range of 1–100 Gy are examined. An ERESCO model 200 MF4-RW X-ray machine has also been used for energy response studies; a Harshaw 3500 TLD reader equipped with WinREMS software was used for the luminescence measurements. All brands exhibit linearity of TL yield versus dose, the samples from Honda showing the greatest response followed by that of the Toyota and Proton brands. The marked energy dependence reflects the effect of the strongly Z-dependent photoelectric effect. Signal fading was investigated over a period of 28 days, the Toyota and Proton brand windshield glass showing a relatively low loss at 52.1% and 52.6% respectively compared to a 56.7% loss for that of the Honda samples. This work forms the first such demonstration of the potential of car windshield glass as a retrospective accident dosimeter.

Thermoluminescence dosimetric attributes of Yb3+‐doped BaO–ZnO–LiF–B2O3 glass material after Er3+ co‐doping

“…Preferably, a TLD should possess a dosimetric peak temperature that is sufficiently large to prevent anomalous fading, while avoiding problems associated with infrared heating cavity emission. [ 7 ] The ZLBBY0.1 glass presented the highest integrated TL intensity among the ZLBBY(0/0.1/0.5/0.7/1) glass samples with the composition 10BaO–20ZnO–20LiF–(50– x )B 2 O 3 – x Yb 2 O 3 at different molar percentages when all were irradiated with 3 kGy gamma dose. [ 16 ] The glow curve of these glass samples peaked at a temperature of ~500 K, and even contained a shoulder peaking ~410 K. The inclusion of 0.1 mol% Yb 2 O 3 in temperatures between 323 and 660 K produced an integrated TL intensity of the ZLBBY0 glass sample that was 26 times higher than its original value.…”

“…The glow curve area, or the integrated TL intensity per unit mass of the dosimeter per unit dose also indicated the TL sensitivity. [ 7 ] The TL sensitivity of the ZLBBY0.1E0.1 glass as presented in Figure 5 was 60,841 counts −1 g −1 kGy −1 , which was significantly less than that of the ZLBBY0.1 glass [ 16 ] (198,992 counts −1 g −1 kGy −1 ). This reduction in the TL sensitivity, without a change in the linearity range, was due to the diminished TL intensity after co‐doping the ZLBBY0.1 glass with Er 3+ ions.…”

“…For a material with a homogenous composition, the radiation interaction is dependent on its atomic number ( , whereas for a material with heterogenous composition or a multielement material such as glass, a parameter called the ‘effective atomic number’ ( is analogous to [ 7,8 ] The is the key in seeking an accurate estimation of the absorbed dose. [ 7 ] The can be calculated from the density of the heterogenous composition medium. The density of the ZLBBY0.1E0.1 glass was obtained as 2.9966 g cm −3 .…”

“…The thermal fading parameter, which measures the post‐irradiation stability of the TL signal, is crucial to specify the radiation monitoring application of a TLD. [ 7 ] While the TLD is stored, environmental circumstances such as temperature and humidity effect the fading rate of the absorbed dose. [ 24 ] A negligible fading rate guarantees a high degree of accuracy when the TLD is read out after its time in storage.…”

“…For retrospective dosimetry applications extending over weeks, months, or even years, a highly thermally stable TLD material with deep‐seated electron traps is preferable. [ 7 ] The results suggest that the thermal stability of the ZLBBY0.1 glass can be optimally modified by the introduction of 0.1 mol% Er 2 O 3 , making the glass system suitable for radiation monitoring.…”