Dose rates were not dangerously high in many areas of Fukushima that were subject to decontamination. In fact,doses were relatively lowin the first year following the accident (less than 12,000 µSv), and these levels decreased significantly in subsequent years.
These levels fall within thenatural range people are exposed tofrom radioactivity in rocks, soils, building materials and cosmic radiation worldwide (typically between 1,000 µSv and 10,000 µSv per year, but sometimes higher).