文摘
Dose reduction factor (RF) was summarized from measurements around 200 houses in a less contaminated area of Fukushima. Reductions in indoor dose rates were found to occur with the existence of an uncontaminated area. In this study, this effect was referred to as the “uncontaminated effect”. For measurement of outdoors, a man-borne survey around the house was an effective way to obtain the detailed distribution. It is imperative to recognize that RF fluctuates with various factors related to a house and its surrounding environment.