This study explored changes in spatial radiation dose rate both indoor and outdoor associated with a decontamination operation for a wooden house in a high dose rate region in Fukushima. As a result, the averaged spatial dose rate at 1m height from the floor before the decontamination was 1.73μSv/h and the dose rate after the decontamination was 0.86μSv/h. Furthermore, the results of a comparison of the dose rate between pre- and post-decontamination indicates a decrease in the dose rate at almost all points. The reduction rate of spatial dose-rate was 40 to 50% at the center of the house.
