Papers by Keyword: Radon

Abstract: The research is primarily focused on the determination of humidity on radon volume activity in different soil gas permeabilities in a given land. The research also included the detrermination of the radon index in the given land. The mean concentrations of radon in soil gas during the drought ranged from 15.9 - 24.1 kBq/m³ and in the precipitation period 16.3 - 26.7 kBq/m³. The first area was characterized by low gas permeability of soils, where a low radon index was determined during the dry season and a medium radon index was determined in the precipitation period. The second area, the medium gas permeability of the soils was determined from the analysis of the collected soil samples. The values of the third quartile in both cases measurements of radon volume activity in soil gas fall into the middle class of radon index. The third location would be determined by high gas permeability of soils. The radon index of the given land during the drought was determined as the medium, as in the case of measurement of radon volume activity in soil gas in the period with added moisture in the soil profile. The analysis confirmed the effect of moisture on the volume activity of radon.

Abstract: In article results of a complex research of activity of natural radionuclides in construction raw materials of the Volgograd region are stated. The analysis of frequency distribution of effective specific activity of natural radionuclides in construction materials was carried out. It was revealed that the population of the Volgograd region is more exposed to radiation from construction materials, than on average across Russia. The radiation control while developing and marketing of construction materials to is a possible way to decrease a dosage power in premises.

Abstract: Three of Light Foamed Concrete (LFC) have been obtain by using different formula of Cement:Aggregates. The brick was locate into a closed Perspex box and the net of 222Rn concentration level have been measured for 5 consecutive days. The results show the LFC 3 has produced the lowest of net 222Rn concentration level in air, followed by LFC 2 and LFC 1, respectively. The result also show the 222Rn concentration level have been influenced by the temperature and relative humidity in air.

Abstract: Leakages of hydrocarbon reservoirs often increase the radon concentration on the soil surface through distinct pathways; gas migration results in either prolific macro-seeps or micro-seeps. Soil gases, including radon, are recognized as potential tracers in geoscience. The surficial radiometric anomalies over hydrocarbon reservoirs provide the oil community with a complementary survey tool for oil exploration through the use of nuclear track methodology. The Solid State Nuclear Track Detector (SSNTD) is one of the recognized techniques to be employed advantageously in radon surveys for hydrocarbon exploration and occurrence of natural gas seeps. The nuclear track method provides information on the nature of radioactive gas sources, emanations from the soil and their transport pathways. Latent track etching conditions and their analysis are included.

Abstract: The present paper studies the indoor radon variations in two similar dwellings, one of them occupied and the other unoccupied, from the same residential building. In particular, the research study was carried out in two new dwellings in Madrid. Radon concentration and ambient parameters were measured three-hourly from 11 May to 12 December 2014. Solid state detectors, Radon Scout, were used for the radon monitoring. Simultaneously, two atmospheric variables were acquired from NOAA Air Research Laboratory. The results show that radon level is slightly higher in the unoccupied dwelling than in the other one. From the analysis developed in this study, it is found that a specific seasonal pattern exists in the indoor radon concentration. Besides, the anthropogenic influence is also analysed. Nearly periodical patterns could be observed in specific periods whether dwelling is occupied or not.

Abstract: The article presents the most important results of radon research in Poland. Large-scale research, launched in this country in the early 1950s, was originally linked to using radon dissolved in groundwater in balneotherapy as well as to uranium ore exploration and mining. This early research focused on the area of the Sudetes and nowadays it is also south-western Poland where most radon research is being conducted. This is chiefly due to the geological structure of the Sudetes and the Fore-Sudetic block, which is propitious to radon accumulation in many environments. Radon research in Poland has been developing dynamically since the 1990s. A lot of research teams and centres have been formed, all of them using a variety of methods and advanced measurement equipment enabling research into radon occurrence in all geospheres and all spheres of human activity. The author presents the contribution of Polish science to broadening human knowledge of the geochemistry of radon, particularly of ²²²Rn isotope. The article also presents the ranges and mean values of ²²²Rn activity concentration measured in different environments in Poland including the atmospheric air, the air in buildings and underground hard-coal and copper mines, the cave air, the air in underground tourist sites and abandoned uranium mines, as well as soil air and groundwater.

Abstract: The importance of measuring the decay products of ²²²Rn (radon) and ²²⁰Rn (Thoron) is being realized by researchers as these are the major inhalation dose givers to the general population. Basically the decay products are radioisotopes of Polonium, Bismuth and Lead, which are solid particles. Upon inhalation, these particles deposit in different parts of the respiratory tract, undergo radioactive decay and irradiate the nearby tissues. So, the study of the behavior of the decay products in indoor air is important for assessing the natural background radiation exposures received by general populations through the inhalation route. Although the inhalation doses are predominantly due to decay products yet it had been the usual practice to measure the gas concentration rather than the decay products because of the complexities involved in their detection. The most common method is to derive the progeny concentration from the measured gas concentration using an assumed equilibrium factor. While this is fairly justified for radon in view of the short-lived nature of the progeny as compared to the gas, this approach is beset with serious limitations in thoron-rich environments. However, the development of passive detection system for the decay products known as deposition-based Direct Radon and Thoron Progeny Sensors, has provided a solution to the long standing problem of measuring the time integrated decay product activity concentration. These deposition sensors are calibrated against active measurement techniques, and provide an easy to use method for passive and simultaneous time integrated decay product measurement. In addition, for multi-parametric study, the different modes of these passive sensors, like flow-mode and wire-mesh capped mode, are also used. These are further discussed in the manuscript.

Abstract: Solid State Nuclear Track Detectors (SSNTDs) have been widely used for time integrated radon measurements due to their cost effectiveness, portability and easy-to-use feature. In order to obtain a proper measurement of radon using SSNTDs, it is necessary to select a proper exposure mode. The various modes in which the SSNTDs can be exposed are: (i) bare mode, (ii) single cup mode, and (iii) twin cup mode. This paper addresses the merits and demerits of SSNTDs used in each type of mode of exposure for radon monitoring. The paper analyses the results of the conventional bare mode as well as the latest twin cup mode of SSNTDs. The paper also analyses the performance comparison of single entrance vis a vis double entrance type twin cup dosimeter. Design and features of the newly developed pinhole based single entrance twin cup dosimeter have been discussed. A protocol has been proposed for the selection of houses and deployment of the dosimeter. Some of the important findings from laboratory and field experiments of the new device have been presented.

Abstract: In this paper we present the preliminary results of a study of the radon and thoron (²²²Rn and ²²⁰Rn) and their progeny, concentration distribution inside the cellar as recorded by a 200×200 cm mesh of CR-39 bare detectors. The mesh comprised one hundred and sixty two 1.9×0.9 cm CR-39 (Lantrack^®) polycarbonate chips. The distribution of radon and thoron shows a complex pattern. Both sides of the mesh displayed a significant concentration gradient of radon and thoron levels, with a maximum near to the top and bottom of the detection grid, and minimum around the center. This spatially inhomogeneous distribution recorded by the detectors could be the result of the distance from the walls, gas kinematics, diffusion coefficient, room geometrical configuration, aerosol behaviors, and objects inside the room, among others. It suggests that the analysis of these complex distribution patterns may be applicable for the estimation and evaluation of indoor radon concentration levels, considering each particular location and characteristics of the place.

Abstract: This study aims to determine permeable zones (i.e. fault or fracture zones) in the Rajabasa geothermal field using radon isotopes. Radon concentration of soil gas was measured by Scintrex Radon detector RDA 200 consisting of 123 measurement station. The measurement site spacing are between 200 m and 350 m. The Radon concentration was classified based on a statistical approach, i.e. low, high and very high. Very high value of Radon concentration, called Radon anomaly, associated with permeable zones. From the Radon anomaly contour map, a 2D Radon migration from the source to the surface was modelled by means of numerical simulation. Finally, the Radon contour map was overlaid with the surface geological map and the resistivity contour map in the area of study. It suggests that the Radon anomaly correlates with the location of permeable zone in the centre part of the study area i.e. mud pool manifestation at the Kunjir and the Cugung (Bulakan) fumarole. Based on numerical simulation, the width of the fault is 2,800 m; velocity of fluid is 0.08 m/s and the Radon concentration is 860,000 Beq/m³. The resistivity contour map results low resistivity value of 0 Wm – 100 Wm indicating the conductive zone coincide with permeable zones based on Radon measurements. Furthermore, the peak of the profile curve of Radon concentration could be an indication of fault systems in this area.