Document Type



Environmental Radon, Radon Measurements, Environmental Radon Sources


Radon concentrations in air in main floor areas of 213 houses in Central and Eastern Iowa were measured with alpha track detectors integrating over periods of five months to one year. Forty-two houses in Central Iowa had significantly higher radon concentrations (lognormal distribution with geometric mean 2.1 pCi/L, geometric standard deviation 2.2, and arithmetic mean 2.75 pCi/L) than 171 houses studied in Eastern Iowa (geometric mean 1.6 pCi/L, geometric standard deviation 2.2, arithmetic mean 2.1 pCi/L). Significant differences in radon levels were found among different categories of houses with regard to ventilation rate, basement construction, and cracks and openings in basements. Almost every category with more than a few houses in it contained houses with annual average main-floor radon levels over 4.0 pCi/L. Liquid scintillation measurements of radon in the water supplies of the houses showed, for 50 private wells: high 1700, average 490, and geom. mean 350 pCi/L, with geom. st'd. dev. 2.8; and for 21 public supplies: high 740, average 210, and geom. mean 130 pCi/L, with geom. st'd. dev. 3.1. Radon in the water supplies was not correlated with radon in the air in the houses. A method for measuring radon in the soil gas was developed and with it the soil-gas radon was measured near 40 of the houses in Central Iowa. Soil gas radon levels ranged from 40 to 1200 pCi/L, with average 380 and geom. Mean 290 pCi/L, and geom. st'd. dev. 2.2. Radon in soil gas was not correlated with radon in air in the houses.

Publication Date

September 1990

Journal Title

Journal of the Iowa Academy of Science





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© Copyright 1990 by the Iowa Academy of Science, Inc.



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