Comparison of Dose Rates from Four Surveys around the Fukushima Daiichi Nuclear Power Plant for Location Factor Evaluation

Background: The radionuclides released by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident 9 years ago are still being monitored various research teams and Japanese government. Comparison of different surveys’ results could help evaluate exposure doses mechanism radiocesium behavior in urban environment area. In this study, we clarified relationship between land use temporal changes ambient dose rates (air rates) using big data.Materials Methods: We set a series 1 × km2 meshes within 80 km zone FDNPP to compare survey results. then prepared an analysis dataset from all analyze change air rate. selected included data types (airborne, fixed point, backpack, carborne) obtained through all-time campaigns.Results Discussion: characteristics each survey’s were evaluated dataset, as they depended on measurement object. revealed that, for example, carborne smaller than those other surveys because field view was limited paved roads. location factor uses also considering four methods. Nine after accident, ranged 0.26 0.49, while half-life rate 1.2 1.6.Conclusion: found that decreasing trend similar Chernobyl accident. These parameters will be useful prediction future at post-accident.