An external exposure from 137Cs deposited on the surface soil is one of the important exposure pathways after an accident in a nuclear facility. In our previous study, it was found that the ratio of rapid component to total activity was most important parameter for dose estimation by using a 2-component removal model from surface soil. In this study, the differences of the probability density functions of the ratios of rapid components due to soil types was investigated by using the monitoring data on the concentration of 137Cs in the surface soil layers around the Chernobyl Nuclear Power Plant. It was discovered that the probability density functions of the ratios of rapid components vary with the soil types and these differences cause the differences in estimated values of integrated dose. This result indicated that information on soil types was useful for the reduction of uncertainty of dose estimation.
Low-level proton beams from a van de Graaff accelerator operated at 1-3MeV with proton dose from 1.48 to 94.56mGy using the Rutherford backscattering method were used to study the response of thermoluminescence dosimeter CaF2: Tm. The glow curves, TL output and sensitivity obtained were analyzed with respect to proton energy, dose and dose rate. The experimental results indicate that TLD CaF2: Tm may also be used as a proton dosimeter in the low energy range.