After more than 35 years operation the uranium mining and milling facilities near Pécs city in Hungary were finally shut down in 1997. One of the most important and most complicated tasks is the remediation of tailings ponds because of the complexity of c

In Hungary and Slovenia a lot of thermal water occurrences providing mineral water for spas are used for curative therapeutic purposes in cases of locomotor and gastrointestinal diseases. In these balneotherapeutic facilities the atmosphere can contain radon and radon daughters at high concentrations. Radon diffusing from the pores and cracks of the minerals being dissolved in underground waters is taken up by spa wells and in the spas the radon emanates from the water.

The aim of this study is to evaluate the efficiency of different ventilation strategies for a house and fora subfloor void to reduce the radon concentration level of the indoor air.A steady-state analytical ventilation model is derived to estimate the indoor air radon concentration inhouses on ground floor or with subfloor voids.

Radon and thoron and their decay products are the most important sources of radiation exposure to thegeneral public, contributing on average about half of the total effective dose equivalent received fromnatural and man-made radioactivity, such situation is encountered also in Poland. The short-liveddecay products of 222Rn decay to 210Pb with half-life of 22 years contribute to the inhaled effectivedose of man.The estimation of radon risk in Poland is made on the basis of radon concentration in soil gas.

The effect on fertility of chronic exposure of female Wistar rats in “Avram Iancu” uranium mine to high Radon-222 and Radon-222 progeny concentrations in air was investigated. Time variations of fertility index as well as the histological aspect of ovarie

CRR, the Regional Center for Radioactivity, is monitoring Veneto, a region in the north-east of Italy, to trace a map of areas with elevated indoor radon levels. This survey is based on analysis of territorial distribution of radon concentration in dwellings. Maps of potential risk are searched in the upper part of the region based on the indication of a previous survey. Percentage of dwellings exceeding reference levels are estimated on the base of log-normal data distribution. Normalizations to ground floor or average housing type are produced.

This paper presents the experimental results of utilizing Electro-Osmotic Pulsing Technology toreduce the diffusion of radon soil gas through a concrete slab. A laboratory system with state-of-theartinstrumentation has been used to measure the diffusion coefficient of radon soil gas through 30.5cm diameter, 10.2 cm thick standard composition concrete samples (w/c = 0.5 and cement:sand:gravel= 1:2:4). Within these concrete samples, a triple titanium anode configuration is embedded while anexternal copper rod is used as the cathode.

This paper presents the experimental results of utilizing a flexible thin-film membrane as a passivebarrier to radon gas diffusion. Nine commercially available membranes of various compositions andthicknesses were evaluated as retardant to radon gas diffusion. The radon gas concentration ratiosacross the thin-film membranes alone and in combination with an adjacent concrete sample (effectivediffusion coefficient) were measured in a laboratory system with state-of-the-art instrumentation.

The first Norwegian study of historic radon concentrations in 17 dwellings in the high radon areas inNorway has been conducted as part of an international field intercomparison during 1998. Theinvestigation is part of SINI (an acronym for Sweden, Italy, Norway and Ireland) internationalcollaboration on retrospective radon measurements in several European countries having differentclimates and living conditions.

Ventilation systems are known to influence radon concentrations indoors considerably. However, the initial results of the largest radon survey in 3660 Norwegian kindergartens conducted during heating seasons from 1996 to 1998 showed marginal effect of such systems. Clarification of this surprising result required a more detailed secondary investigation in a smaller group of kindergartens with balanced ventilation systems operating under special ventilation regime.