Abstract
Radon mass exhalation rate of soil samples was measured using an exhalation chamber of 10 dm3 volume and a Lucas cell. The results show that mass of sample, grain size and water content influence the radon mass exhalation rate. For soil of 226Ra activity concentration about 2500 Bq kg1 and samples within the range from 0.20 kg to 0.50 kg, the radon mass exhalation rate values are higher than those for samples of other masses. The observed radon exhalation rate is an inverse function of the average grain size. At the water content about 6% by weight, the radon mass exhalation rate reaches maximum, then it decreases with both increasing and decreasing of the water content in the sample. 2005 Elsevier Ltd. All rights reserved.
Keywords: Radon mass exhalation rate; Sample mass; Grain size; Water content
1. Introduction
Contribution of radon (and its progenies) in air to the total effective dose due to natural radioactivity exceeds 50%, (UNSCEAR, 2000; Porstendo¨ rfer, 1993), so
* Corresponding author.
0265-931X/$ - see front matter 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.jenvrad.2005.02.006
AbstractRadon mass exhalation rate of soil samples was measured using an exhalation chamber of 10 dm3 volume and a Lucas cell. The results show that mass of sample, grain size and water content influence the radon mass exhalation rate. For soil of 226Ra activity concentration about 2500 Bq kg1 and samples within the range from 0.20 kg to 0.50 kg, the radon mass exhalation rate values are higher than those for samples of other masses. The observed radon exhalation rate is an inverse function of the average grain size. At the water content about 6% by weight, the radon mass exhalation rate reaches maximum, then it decreases with both increasing and decreasing of the water content in the sample. 2005 Elsevier Ltd. All rights reserved.Keywords: Radon mass exhalation rate; Sample mass; Grain size; Water content1. IntroductionContribution of radon (and its progenies) in air to the total effective dose due to natural radioactivity exceeds 50%, (UNSCEAR, 2000; Porstendo¨ rfer, 1993), so* Corresponding author.0265-931X/$ - see front matter 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.jenvrad.2005.02.006
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