EFFECTIVE INDOOR DOSE OF GAMMA RADIATION FROM BUILDING MATERIALS: COMPARISON OF SEVERAL METHODS FOR ESTIMATION AND POSSIBLE UNDERESTIMATE.

This paper compares several methods for estimation of the effective indoor dose of gamma radiation from building materials. It was found that specific dose ratios proposed for 3 cm thick layers in one recommendation gives 2.8 times lower value of gamma dose than other methods. The most common case is that granite has an elevated content of natural radionuclides and it is usually used in the form of decorative layers. If the decision about restricted or non-restricted use of granite as a building material is based on method which underestimate gamma dose, there is reasonable concern that materials having elevated concentrations of natural radionuclides than allowed will be used in dwellings. In addition, it is pointed out that existing regulations allow in some cases non-restricted use of building materials even in the case when their activity concentrations exceed exception limits.

Impact of climate change on soil thermal and moisture regimes in Serbia: An analysis with data from regional climate simulations under SRES-A1B.

We considered temporal and spatial variations to the thermal and moisture regimes of the most common RSGs (Reference Soil Groups) in Serbia under the A1B scenario for the 2021-2050 and 2071-2100 periods, with respect to the 1961-1990 period. We utilized dynamically downscaled global climate simulations from the ECHAM5 model using the coupled regional climate model EBU-POM (Eta Belgrade University-Princeton Ocean Model). We analysed the soil temperature and moisture time series using simple statistics and a Kolmogorov complexity (KC) analysis. The corresponding metrics were calculated for 150 sites. In the future, warmer and drier regimes can be expected for all RSGs in Serbia. The calculated soil temperature and moisture variations include increases in the mean annual soil temperature (up to 3.8°C) and decreases in the mean annual soil moisture (up to 11.3%). Based on the KC values, the soils in Serbia are classified with respect to climate change impacts as (1) less sensitive (Vertisols, Umbrisols and Dystric Cambisols) or (2) more sensitive (Chernozems, Eutric Cambisols and Planosols).

Beryllium-7 and (210)Pb atmospheric deposition measured in moss and dependence on cumulative precipitation.

This paper focuses on analysis of the time series of (7)Be and (210)Pb activity measured in moss, and the amount, as well as duration of precipitation, to gain a better understanding of the possible relationships between airborne radionuclide deposition and precipitation. Here we consider whether the amount of these airborne radionuclides in moss samples is a cumulative measure of radionuclide deposition and decay, and a new approach for analyses of the relationships between precipitation and moss activity concentrations is suggested. Through these analyses it was shown that comparison of cumulative activity measured at one location using moss, normalized by values of cumulative amount or duration of precipitation, showed different regimes of airborne radionuclide deposition.

A complexity measure based method for studying the dependance of 222Rn concentration time series on indoor air temperature and humidity.

We have suggested a complexity measure based method for studying the dependence of measured (222)Rn concentration time series on indoor air temperature and humidity. This method is based on the Kolmogorov complexity (KL). We have introduced (i) the sequence of the KL, (ii) the Kolmogorov complexity highest value in the sequence (KLM) and (iii) the KL of the product of time series. The noticed loss of the KLM complexity of (222)Rn concentration time series can be attributed to the indoor air humidity that keeps the radon daughters in air.