Estimation of Rn-222 release from the phosphogypsum board used in housing panels

Phosphogypsum board is a popular construction material used for housing panels in Korea. Phosphogypsum often contains Ra-226 which decays into Rn-222 through an a transformation. Rn-222 emanated from the Ra-226-bearing phosphogypsum board has drawn the public concern due to its potential radiological impacts to indoor occupants. The emanation rate of Rn-222 from the board is estimated in this paper. A mathematical model of the emanation rate of Rn-222 from the board is presented and validated through a series of experiments. The back diffusion effect due to accumulation of Rn-222-laden air was incorporated in the model and found to have a strong impact on the Rn-222 emanation characteristics. (C) 2004 Published by Elsevier Ltd.