Investigation and evaluation of radon concentrations in coal mines in Shandong province

Investigation and measurement were carded out of the radon concentrations, γ radiation dose rate and naturally occurring radionuclides in coal in the selected 22 different types of coal mines in Shandong Province, together with estimating the radiation dose to the underground miners. The measured data shows that the radon concentration, γ radiation dose rate and annual effective dose to the underground miners were (48.53 ± 45.87)Bq/m3, (0.199 ± 0.017) μGy/h and 0.571 mSv in the state-owned large and medium-sized coal mines, 63.97 ± 89.18) Bq/m3, (0.144 ± 0.026) μGy/h and 0.601 mSv in local small and medium-sized coal mines. These results show that the level of radon concentration and γ radiation dose in coal mines in Shandong Province are low. (authors)