Environmental radon and radon daughters

Measurements have been made on radon and radon daughters since the fall of 1977. An account is given of the measurement methods used and results obtained in the current year. Monthly average radon concentrations at Chester, measured at elevations of 1 and 10 meters above ground, follow the same pattern. The average concentration of radon at 10 meters was found to be 40% lower than that found near the ground. Results indicate that most of the radon and radon daughters near the ground are of local origin, and some radon daughter plateout is occurring. The radon concentration and flux were compared to meteorological parameters. One parameter that seems to exert influence on radon concentration is wind speed, a factor observed in two successive years of study. Another factor that seems to affect radon emanation and radon concentration is the temperature of the soil (not measured at Chester), often showing a substantial reduction in flux (factor of 4 lower than annual mean) during the cold months when the soil freezes