気中自然放射能測定における測定地点の地域代表性
1981 年 16 巻 2 号 p. 123-133
詳細
1981 年 16 巻 2 号 p. 123-133
The air concentration of radon short-lived daughter products (Rn-Dts) differs considerably with location and time. This fact is the reason why the estimation of radiation doses to the respiratory system due to Rn-Dts is difficult from the viewpoint of population doses. Hence, we attempted to define an equiconcentration area with a uniform air concentration of Rn-Dts. Many points at which we measured Rn-Dts concentration were selected at the inner area within a 30km radius around the reference pointof the campus. Measurements of Rn-Dts concentrations have been carried out between the reference point and a point for comparison at same time. Similar measurements have been continued successively. The values observed at every point within the 15km radius around the reference point were consistent with that observed at the reference point with an error of 20 percent of the concentration ratio of Rn-Dts and above the correlation coefficient of 0.80. The values obtained at every point, excerpt for two points on the granits zone and 100m above sea level, agreed with that observed atthe reference point within an error of 50 percent of concentration ratio of Rn-Dts and over the correlation coefficient of 0.45.
