Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8081801 | Journal of Environmental Radioactivity | 2016 | 8 Pages |
Abstract
A car-borne survey was made in metropolitan Tokyo, Japan, in December 2014 to estimate external dose. This survey was conducted for all municipalities of Tokyo and the results were compared with measurements done in 2003. The ambient dose rate measured in the whole area of Tokyo in December 2014 was 60 nGy hâ1 (23-142 nGy hâ1), which was 24% higher than the rate in 2003. Higher dose rates (>70 nGy hâ1) were observed on the eastern and western ends of Tokyo; furthermore, the contribution ratio from artificial radionuclides (134Cs and 137Cs) to ambient dose rate in eastern Tokyo was twice as high as that of western Tokyo. Based on the measured ambient dose rate, the effective dose rate after the accident was estimated to be 0.45 μSv hâ1 in Tokyo. This value was 22% higher than the value before the accident as of December 2014.
Related Topics
Physical Sciences and Engineering
Energy
Nuclear Energy and Engineering
Authors
Kazumasa Inoue, Hiroshi Tsuruoka, Tan Van Le, Moeko Arai, Kyoko Saito, Masahiro Fukushi,