Inoue K, Arai M, Tsuruoka H, Saito K, Fujisawa M, Nakazawa S, Veerasamy N, Fukushi M
Department of Radiological Sciences, Tokyo Metropolitan University, 7-2-10 Higashiogu, Arakawa-ku, Tokyo, Japan.
Department of Radiological Sciences, Tsukuba International University, 6-20-1 Manabe, Tsuchiura, Ibaraki, Japan.
Radiat Prot Dosimetry. 2019 Oct 1;184(3-4):500-503. doi: 10.1093/rpd/ncz073.
Absorbed dose rates in air were measured for the whole area of the Kanto region in 2015, 2016 and 2017 (n = 31 147). The mean absorbed dose rates in air for each prefecture measured by car-borne surveys were from 44 to 67 nGy h-1 (13-289 nGy h-1). The absorbed dose rate in air from artificial radionuclides (134Cs + 137Cs) measured by fixed-point observation (n = 507) was from 1 to 14 nGy h-1 (0-105 nGy h-1), and meaning that the contribution ratios of 134Cs and 137Cs were 3-22%. The deposited location of artificial radionuclides was less than 1000 m from ground level and depended on the topography, wind direction and precipitation field.
2015年、2016年和2017年对关东地区全域的空气吸收剂量率进行了测量(n = 31147)。通过车载调查测量的各都道府县空气中的平均吸收剂量率为44至67纳戈瑞每小时(13 - 289纳戈瑞每小时)。通过定点观测测量的人工放射性核素(134铯 + 137铯)在空气中的吸收剂量率为1至14纳戈瑞每小时(0 - 105纳戈瑞每小时),这意味着134铯和137铯的贡献率为3% - 22%。人工放射性核素的沉积位置距离地面不到1000米,且取决于地形、风向和降水场。