New model for dwelling dose calculation using Monte Carlo integration

Abstract

A new methodology and computer model using Monte Carlo simulation for indoor dose calculation are developed. A room model of six rectangular slabs of finite thickness with door or window in each slab was used. Point-kernel photon transport model with self-absorption correction was applied for dose calculations. New software was designed and programmed using Pascal programming language, which was evaluated for standard room design. The calculated dose due to natural radionuclides in the concert walls has differences from the average model results of 0.21% for (238)U, 12.3% for (232)Th and 13.9% for (40)K; and the variability of specific dose rate with changing position density and composition of walls was studied. The new model has more flexibility for real dose calculation of any room structure and tailing, which is not given in the published models.

Activity concentrations and dose rates from decorative granite countertops

“…Overviews of the different approaches and direct comparisons of their results are available in Refs. (Markkanen, 1995;Markkanen, 1999;Ahmad et al, 1998;Máduar and Hiromoto, 2004;Allam, 2009;Risica et al, 2001). Generally, the predictions from the different A&B approaches are consistent to the 10e15% level.…”

“…(Koblinger, 1978;Stranden, 1979;Mustonen, 1985a,b) have been developed with slightly different assumptions in Fortran Markkanen, 1995;Markkanen, 1999;Mirza et al, 1991;Ahmad et al, 1998;Máduar and Hiromoto, 2004), Maple (Ademola and Farai, 2005), and Pascal (Allam, 2009). Overviews of the different approaches and direct comparisons of their results are available in Refs.…”

Precise Assessment of gamma absorbed dose rates using different techniques.

“…Risica (2001) [8] has improved the calculations, making use of the γ line 1461 keV for 40 K, weighted mean energy of 810 keV for 238 U and the 2614 keV γ line for 232 Th. Allam (2009) [9] has calculated the indoor absorbed dose conversion factors making use of 24 γ lines in the 238 U chain, 32 γ lines in the 232 Th chain and the 1460 keV γ lines for 40 K applying the same markkanen , s room model dimensions which are 5 x 4 x 2.8 m and floor, wall and ceiling thickness of 0.2m. Accordingly, the aim of the present work is to obtain precise values of the outdoor and indoor absorbed doses using γ-spectroscopy and thermo luminescence techniques, taking into considerations all the detected γ lines attributed to the natural radioactive series and 40 K along with the application of a convenient theoretical model to evaluate the dependence of the γ indoor absorbed dose conversion factors on the configuration of the room.…”