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Sample records for radon diffusion studies

  1. Experimental study of radon and thoron diffusion through barriers

    Energy Technology Data Exchange (ETDEWEB)

    Durcik, M; Havlik, F [Inst. of Preventive and Clinical Medicine, 83301 Bratislava (Slovakia)

    1996-12-31

    The measurement results of diffusion parameters for radon (radon-222) and thoron (radon-220) through barriers, experimental equipment and theoretical background of diffusion are presented in this paper. The diffusion barriers are used for measuring radon and thoron by passive detectors in order to test the reduction techniques in houses. Six samples (filter paper, rubber, polyethylene, glass laminate, polypropylene) were studied for radon diffusion. The thickness barriers were from 0.012 mm to 2 mm, the diffusion area was 16 cm{sup 2} and the volume V{sub 2} was 30 dm{sup 3}. The diffusion constants D were obtained using given expressions and the data from measurements. The procedures used in experiments are useful for study of diffusion ability of radon and thoron in barriers and determination diffusion parameters from short term measurements. (J.K.). 2 figs., 1 tab., 3 refs.

  2. Experimental study of radon and thoron diffusion through barriers

    International Nuclear Information System (INIS)

    Durcik, M.; Havlik, F.

    1995-01-01

    The measurement results of diffusion parameters for radon (radon-222) and thoron (radon-220) through barriers, experimental equipment and theoretical background of diffusion are presented in this paper. The diffusion barriers are used for measuring radon and thoron by passive detectors in order to test the reduction techniques in houses. Six samples (filter paper, rubber, polyethylene, glass laminate, polypropylene) were studied for radon diffusion. The thickness barriers were from 0.012 mm to 2 mm, the diffusion area was 16 cm 2 and the volume V 2 was 30 dm 3 . The diffusion constants D were obtained using given expressions and the data from measurements. The procedures used in experiments are useful for study of diffusion ability of radon and thoron in barriers and determination diffusion parameters from short term measurements. (J.K.). 2 figs., 1 tab., 3 refs

  3. Radon diffusion studies in air, gravel, sand, soil and water

    International Nuclear Information System (INIS)

    Singh, B.; Singh, S.; Virk, H.S.

    1993-01-01

    Radon isotopes are practically inert and have properties of gases under conditions of geological interest. During their brief lives their atoms are capable of moving from sites of their generation. Radon diffusion studies were carried out in air, gravel, sand, soil and water using silicon diffused junction electronic detector, Alphameter-400. Diffusion constant and diffusion length is calculated for all these materials. (author)

  4. Study of the factors affecting radon diffusion through building materials

    International Nuclear Information System (INIS)

    Chauhan, R.P.

    2011-01-01

    Radon appears mainly by diffusion processes from the point of origin following - decay of 226 Ra in underground soil and building materials used, in the construction of floors, walls, and ceilings. The diffusion of radon in dwellings is a process determined by the radon concentration gradient across the building material structure and can be a significant contributor to indoor radon inflow. Radon can originate from the deeply buried deposit beneath homes and can migrate to the surface of earth. Radon diffusion and transport through different media is a complex process and is affected by several factors. It is well known that for building construction materials the porosity, permeability and the diffusion coefficient are the parameters, which can quantify the materials capability to hinder the flow of radon soil gas. An increase in porosity will provide more air space within the material for radon to travel, thus reducing its resistance to radon transport. The permeability of material describes its ability to act as a barrier to gas movement when a pressure gradient exists across it and is closely related to the porosity of material. The radon diffusion coefficient of a material quantifies the ability of radon gas to move through it when a concentration gradient is the driving force. This parameter depends upon the porosity and permeability of the medium. As diffusion process is the major contributor to indoor levels, therefore, the factors affecting the diffusion process need to be kept in consideration. Keeping this in mind the experimental arrangements have been made for control study of radon diffusion through some building materials to observe the effects of different factors viz.; compaction, grain size, temperature, humidity and the mixing of these materials etc. For the present study alpha sensitive LR-115 type II solid-state nuclear track detectors (SSNTDs) have been used for the recording of alpha tracks caused by radon gas after its diffusion through the

  5. Radon diffusion coefficients for soils. Previous studies and their application to uranium-bearing wastes

    International Nuclear Information System (INIS)

    Sasaki, Tomozo; Gunji, Yasuyoshi; Iida, Takao

    2008-01-01

    Radon diffusion in soils has been studied over the years by many researchers. The application of such studies to the evaluation of radiation exposure caused by radon from uranium-bearing wastes disposed in a shallow land site is very important. The present paper surveyed closely relevant studies and elucidated the inherent nature of radon diffusion in terms of the definition of radon diffusion coefficients. Then, basic features of measurement methods for determining radon diffusion coefficients in soils were explained. Furthermore, theoretical aspects of radon diffusion in soils were discussed in terms of microscopic radon diffusion in soils and large-scale radon diffusion through cover soil defects for uranium mill tailings. Finally, in order to apply the radon diffusion studies to uranium-bearing waste disposal in shallow land sites, new challenges were presented: elucidation of radon diffusion in uranium-bearing wastes and cover-soil cracks, and demonstration of the validity of applying only radon diffusion in the evaluation of radiation exposure caused by radon, which would come through Japanese cover soils for uranium-bearing waste disposal. (author)

  6. Radon diffusion studies in some building materials using solid state nuclear track detectors

    CERN Document Server

    Singh, S; Singh, B; Singh, J

    1999-01-01

    LR-115 plastic track detector has been used to study radon diffusion through some building materials, viz. cement, soil, marble chips, sand and lime as well as air. Diffusion constant and diffusion length is calculated for all these materials.

  7. Study of radon diffusion from RHA-modified ordinary Portland cement using SSNTD technique

    International Nuclear Information System (INIS)

    Narula, A.K.; Goyal, S.K.; Chauhan, R.P.; Chakarvarti, S.K.

    2013-01-01

    The diffusion coefficient of radon is a very important factor in estimating the rate of indoor radon inflow. The aim of this work is to develop and assess the potential of radon resistant construction materials in residential buildings. Of late, rice husk ash (RHA) has been used as a component in cement. The X-ray diffraction of RHA indicates that the RHA contains mainly amorphous materials while the X-ray fluorescence analysis shows that the major percentage of it is composed of silica. The amorphous silica present in the RHA is responsible for the pozzolonic activity of the ash. The results of the present study indicate that the RHA when mixed with cement initially reduces radon diffusion coefficient, followed by enhancement when the percentage of RHA is increased above 30% by weight. - Highlights: ► Radon diffusion coefficient has been measured in Portland cement with different percentage of rice husk ash (RHA). ► The mixing of RHA to cement changes the radon diffusion coefficient. ► The mixture of cement and RHA can be used to make building materials more resistant to radon entry through diffusion

  8. Radon diffusion chamber

    International Nuclear Information System (INIS)

    Pretzsch, G.; Boerner, E.; Lehmann, R.; Sarenio, O.

    1986-01-01

    The invention relates to the detection of radioactive gases emitting alpha particles like radon, thoron and their alpha-decaying daughters by means of a diffusion chamber with a passive detector, preferably with a solid state track detector. In the chamber above and towards the detector there is a single metallized electret with negative polarity. The distance between electret and detector corresponds to the range of the alpha particles of radon daughters in air at the most. The electret collects the positively charged daughters and functions as surface source. The electret increases the sensitivity by the factor 4

  9. A Monte Carlo study of radon detection in cylindrical diffusion chambers

    Energy Technology Data Exchange (ETDEWEB)

    Rickards, Jorge, E-mail: rickards@fisica.unam.m [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica, Ciudad Universitaria, Delegacion Coyoacan, 04520 Mexico, D.F. (Mexico); Golzarri, Jose-Ignacio, E-mail: golzarri@fisica.unam.m [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica, Ciudad Universitaria, Delegacion Coyoacan, 04520 Mexico, D.F. (Mexico); Espinosa, Guillermo, E-mail: espinosa@fisica.unam.m [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito de la Investigacion Cientifica, Ciudad Universitaria, Delegacion Coyoacan, 04520 Mexico, D.F. (Mexico)

    2010-05-15

    The functioning of radon diffusion chambers was studied using the Monte Carlo code RAMMX developed here. The alpha particles from radon are assumed randomly produced in the volume of the cylinder, and those from the progeny are assumed to originate randomly at the cylindrical surface. The energy spectrum, the distribution of incident angles, and the distribution of path lengths of the alpha particles on the detector were obtained. These quantities vary depending on input parameters such as initial alpha particle energy, radius and depth of the diffusion chamber, detector size and atmospheric pressure. The calculated energy spectrum for both {sup 222}Rn and {sup 220}Rn was compared with experiment, permitting the identification of each peak and its origin, and a better understanding of radon monitoring. Three aspects not considered in previous calculations are progeny alphas coming from surfaces of the monitor, taking into account the atmospheric pressure, and including the isotope {sup 220}Rn.

  10. Study on the measurement method of diffusion coefficient for radon in the soil. 2

    International Nuclear Information System (INIS)

    Iida, Takao

    2000-03-01

    To investigate radon behavior in the soil at Ningyo Pass, the radon concentrations in the soil and the radon exhalation rate from soil surface were measured by four continuous soil radon monitoring systems, soil gas sampling method, and accumulation method. The radon concentrations in the soil measured with continuous soil radon monitoring systems varied form 5000 Bq·m -3 to 15000 Bq·m -3 at 10 cm to 40 cm depth. On the other hand, the radon concentrations measured by soil gas sampling method was 15000 Bq·m -3 at 15 cm depth. The accumulation method gives the vales of 0. 36∼0.68 Bq·m -2 ·s -1 for radon exhalation rate from soil surface. To simulate the radon transport in soil, the following parameters of the soil are important: radon diffusion coefficients, dry density, wet density, soil particle density, true density, water content and radium concentration. The measured radon diffusion coefficients in the soil were (1.61±0.09)x10 -6 m 2 s -1 , (8.68±0.23)x10 -7 m 2 s -1 ∼ (1.53±0.12)x10 -6 m 2 s -1 and (2.99±0.32)x10 -6 m 2 s -1 ∼ (4.39±0.43)x10 -6 m 2 s -1 for sandy soils of the campus of Nagoya University, Tsuruga peninsula, and Ningyo Pass, respectively. By using these parameters, the radon transport phenomena in the soil of two layers were calculated by analytical and numerical methods. The radon profile calculated by numerical method agrees fairly well with measured values. By covering of 2 m soil, the radon exhalation rate decreases to 1/4 by analytical method, and 3/5 by numerical method. The covering of normal soil is not so effective for reducing the radon exhalation rate. (author)

  11. Influence of moisture content on radon diffusion in soil

    International Nuclear Information System (INIS)

    Singh, M.; Ramola, R.C.; Singh, S.; Virk, H.S.

    1990-01-01

    Radon diffusion from soil has been studied as a function of the moisture content of the soil. A few simple experiments showed that up to a certain moisture content the radon diffusion increased with increasing moisture. A sharp rise in radon concentration occurred as the moisture was increased from the completely dry state to 13% water by weight. The radon flux was measured for columns of dry, moist and water saturated soil. The highest flux came from the column filled with moist soil. Water saturated soil gave the lowest flux because of the much lower diffusion coefficient of radon through water. (author)

  12. Using the thermal diffusion cloud chamber to study the ion-induced nucleation by radon decay

    International Nuclear Information System (INIS)

    Wu, Yefei.

    1991-01-01

    Thermal diffusion cloud chamber is steady-state device and has been extensively used for nucleation research. In order to study the ion-induced nucleation by radon decay, a new chamber was designed with improved both upper and bottom plates, the system of circulating fluid, the gasketting, the temperature measurement and the insulation. An alternative method of using oxygen as carrier gas was examined. Therefore, the heavy carrier gas including nitrogen, oxygen, neon, argon and air can be used to study radon radiolysis-induced nucleation for the water or organic compounds in the TDCC. The effects of the pressure and temperature ranges on the density, supersaturation, temperature and partial pressure profile for the water-oxygen-helium in the TDCC have been examined. Based on the classical theory, the rate profile of ion-induced nucleation by radon decays was calculated and compared with the homogeneous nucleation. From measured indoor concentrations of Volatile Organic Compounds (VOC), thermodynamic theory models were used to assess the possibility that these compounds will form ultrafine particles in indoor air by ion-induced nucleation. The energy, number of molecules and equilibrium radius of clusters have been calculated based on Such and Thomson theories. These two sets of values have been compared. Ion cluster radii corresponding to 1--3 VOC molecules are in range of 3--5 x 10 -8 cm. 43 refs., 18 figs., 5 tabs

  13. Natural radon as a limnological tracer for the study of vertical and horizontal eddy diffusion

    International Nuclear Information System (INIS)

    Imboden, D.M.

    1979-01-01

    Radon-222 (half-life 3.8 d) has been used successfully as a geochemical tracer for vertical near bottom mixing in the ocean. The parent nuclide radium-226 (half-life 1600 a) occurs in far greater quantities in sediments than in the water column, thus providing a boundary source for emanation of radon. Vertical mixing in lakes may be of central importance for the evolution of chemical and biological processes. Most lakes pass through a stagnation period during which the euphotic zone continuously loses nutrients by sedimentation of plankton through the thermocline. The return flux of nutrients from the sediments through the hypolimnion and thermocline to the euphotic layer can only be understood and quantified if vertical mixing processes are known. The traditional means by which vertical eddy diffusion is calculated is the temperature method. However, temperature changes near the bottom of deep lakes are often too small to be measured. Among various (natural or man-made) geochemical tracers radon-222 seems to be especially suitable for the study of vertical mixing since its 'memory' of about one week very often allows measured activities to be interpreted in terms of a relatively simple steady-state model

  14. The effect of laterite density on radon diffusion behavior.

    Science.gov (United States)

    Li, Yongmei; Tan, Wanyu; Tan, Kaixuan; Liu, Zehua; Fang, Qi; Lv, Junwen; Duan, Xianzhe; Liu, Zhenzhong; Guo, Yueyue

    2018-02-01

    Radon generated in porous media such as soils and rocks migrates into indoor and outdoor air mainly by diffusion, possessing significant hazards to human health. In order to reduce these hazards of radon, it is of great importance to study the diffusion behavior of radon. In this study, we systematically measured the radon diffusion coefficient of laterite with the density ranging from 0.917gcm -3 to 2.238gcm -3 , and studied the effect of laterite density on the radon diffusion. The results show that the radon diffusion coefficient of the laterite generally decreases with the increasing laterite density. In addition, three possible relationships between the radon diffusion coefficient and the laterite density are found out as follows: (1) the linear correlation with a slope of -4.48 × 10 -6 for laterite with density ranging from 0.917 to 1.095gcm -3 , (2) the exponential correlation for laterite with density from 1.095 to 1.63gcm -3 , (3) linear correlation with a slope of -3.1 × 10 -7 for laterite with density from 1.63 to 2.238gcm -3 . The complex relationship between the radon diffusion coefficient and density is caused by the change of porosity and tortuosity of the laterite. Therefore, we suggest that a suitable density should be adopted while using the laterite to effectively cover uranium tailings or economically produce building materials that can curb the radon exhalation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Multidimensional simulation of radon diffusion through earthen covers

    International Nuclear Information System (INIS)

    Mayer, D.W.; Gee, G.W.

    1983-01-01

    The purpose of this report is to document applications of the RADMD model used at PNL to perform analyses of radon diffusion through uranium mill tailings cover systems. The accuracy of the numerical formulation of the RADMD model was demonstrated through a comparison with a two-dimensional analytic solution to the radon diffusion equation. Excellent agreement was obtained between two-dimensional radon concentration profiles predicted by RADMD and those obtained with the analytic solution. A simulation was made of radon diffusion into a test canister using the two dimensional capabilities of RADMD. The radon flux profile was computed and illustrates the effects of the canister on the surface radon flux. The influence of the canister on the radon flux was shown to be significant under certain circumstances. Defects in earthen cover systems were evaluated using the three dimensional capabilities of RADMD. The results support the expectation that defective covers can increase the surface flux from a covered talings pile. Compared to a cover with no defects, radon flux could be elevated by as much as a factor of three when 20% of the radon control layer area contained pockets of reduced moisture. The effects of temporal and spatial variations in moisture content have been modeled by coupling RADMD with a variable saturated flow model. Two dimensional simulations were made of the time dependence of radon flux from a tailings site before and after cover placement. The results demonstrated the expected flux reduction produced by a thick earthen cover. Time dependence of the radon flux after cover placement was attributed to slight changes in moisture content of the cover material with time. The particular cover studied had a compacted clay layer that effectively attenuated the radon

  16. Radon exhalation rates corrected for leakage and back diffusion – Evaluation of radon chambers and radon sources with application to ceramic tile

    Directory of Open Access Journals (Sweden)

    M. Abo-Elmagd

    2014-10-01

    Full Text Available The natural radon decay, leakage and back diffusion are the main removal processes of radon from its container. Ignoring these processes leads to underestimate the measured value of radon related parameters like exhalation rate and radium content. This work is aimed to evaluate two different radon chambers through determining their leakage rate λv and evaluation of radon source by determine its back diffusion rate λb inside the evaluated radon chambers as well as a small sealed cup. Two different methods are adapted for measuring both the leakage rate and the back diffusion rate. The leakage rate can be determined from the initial slope of the radon decay curve or from the exponential fitting of the whole decay curve. This can be achieved if a continuous monitoring of radon concentration inside the chamber is available. Also, the back diffusion rate is measured by sealing the radon source in the chamber and used the initial slope of the buildup curve to determine λb and therefore the exhalation rate of the source. This method was compared with simple equation for λb based on the ratio of the source to the chamber volume. The obtained results are applied to ceramic tile as an important radon source in homes. The measurement is targeted the ceramic glaze before and after firing as well as the obtained tile after adhere the glaze on the tile main body. Also, six different tile brands from Egyptian market are subjected to the study for comparison.

  17. Inverse method for determining radon diffusion coefficient and free radon production rate of fragmented uranium ore

    International Nuclear Information System (INIS)

    Ye, Yong-jun; Wang, Li-heng; Ding, De-xin; Zhao, Ya-li; Fan, Nan-bin

    2014-01-01

    The radon diffusion coefficient and the free radon production rate are important parameters for describing radon migration in the fragmented uranium ore. In order to determine the two parameters, the pure diffusion migration equation for radon was firstly established and its analytic solution with the two parameters to be determined was derived. Then, a self manufactured experimental column was used to simulate the pure diffusion of the radon, the improved scintillation cell method was used to measure the pore radon concentrations at different depths of the column loaded with the fragmented uranium ore, and the nonlinear least square algorithm was used to inversely determine the radon diffusion coefficient and the free radon production rate. Finally, the solution with the two inversely determined parameters was used to predict the pore radon concentrations at some depths of the column, and the predicted results were compared with the measured results. The results show that the predicted results are in good agreement with the measured results and the numerical inverse method is applicable to the determination of the radon diffusion coefficient and the free radon production rate for the fragmented uranium ore. - Highlights: • Inverse method for determining two transport parameters of radon is proposed. • A self-made experimental apparatus is used to simulate radon diffusion process. • Sampling volume and position for measuring radon concentration are optimized. • The inverse results of an experimental sample are verified

  18. Radon diffusion through multilayer earthen covers: models and simulations

    International Nuclear Information System (INIS)

    Mayer, D.W.; Oster, C.A.; Nelson, R.W.; Gee, G.W.

    1981-09-01

    A capability to model and analyze the fundamental interactions that influence the diffusion of radon gas through uranium mill tailings and cover systems has been investigated. The purpose of this study is to develop the theoretical basis for modeling radon diffusion and to develop an understanding of the fundamental interactions that influence radon diffusion. This study develops the theoretical basis for modeling radon diffusion in one, two and three dimensions. The theory has been incorporated into three computer models that are used to analyze several tailings and cover configurations. This report contains a discussion of the theoretical basis for modeling radon diffusion, a discussion of the computer models used to analyze uranium mill tailings and multilayered cover systems, and presents the results that have been obtained. The study has been conducted using a four-phase approach. The first phase develops the solution to the steady-state radon-diffusion equation in one-dimensieered barriers; disposal charge analysis; analysis of spent fuel policy implementation; spent f water. Field measurements and observations are reported for each site. Analytical data and field measurements are presented in tables and maps. Uranium concentrations in the sediments which were above detection limits ranged from 0.10 t 51.2 ppM. The mean of the logarithms of the uranium concentrations was 0.53. A group of high uranium concentrations occurs near the junctions of quadrangles AB, AC, BB, a 200 mK. In case 2), x-ray studies of isotopic phase separation in 3 He-- 4 He bcc solids were carried out by B. A. Fraass

  19. Study of radon transport through concrete modified with silica fume

    International Nuclear Information System (INIS)

    Chauhan, R.P.; Kumar, Amit

    2013-01-01

    The concentration of radon in soil usually varies between a few kBq/m 3 and tens or hundreds of kBq/m 3 depending upon the geographical region. This causes the transport of radon from the soil to indoor environments by diffusion and advection through the pore space of concrete. To reduce indoor radon levels, the use of concrete with low porosity and a low radon diffusion coefficient is recommended. A method of reducing the radon diffusion coefficient through concrete and hence the indoor radon concentration by using silica fume to replace an optimum level of cement was studied. The diffusion coefficient of the concrete was reduced from (1.63 ± 0.3) × 10 −7 to (0.65 ± 0.01) × 10 −8 m 2 /s using 30% substitution of cement with silica fume. The compressive strength of the concrete increased as the silica-fume content increased, while radon exhalation rate and porosity of the concrete decreased. This study suggests a cost-effective method of reducing indoor radon levels. -- Highlights: • Radon diffusion study through silica fume modified concrete was carried out. • Radon diffusion coefficient of concrete decreased with increase of silica fume contents. • Compressive strength increased with increase of silica fume. • Radon exhalation rates and porosity of samples decreased with addition of silica fume. • Radon diffusion coefficient decreased to 2.6% by 30% silica fume substitution

  20. Use of radon-222 as a tracer in the study of atmospheric diffusion

    International Nuclear Information System (INIS)

    Ikebe, Y.; Yamada, H.; Nishimura, T.; Kojima, S.; Shimo, M.; Yamanishi, H.; Tojyo, K.; Iida, T.; Chino, M.

    1991-01-01

    222 Rn is one of the most useful tracer for studying the atmospheric diffusion. In this report, first we report analytical treatments about temporal variation of Rn concentration in the atmosphere to clarify origin and transport of Rn. Secondly we report the numerical simulation of the behavior of Rn. The results is compared with the observed Rn concentration for confirming the validity of the simulation. Based on the results of numerical analysis of a diffusion equation, we assumed that Rn concentration measured at Nagoya can be divided into the following two components: (I) Rn atom originated near from the measuring site, which is denoted by 'diurnal variation component'. For this, it was shown that the measured temporal variation can be explained by using ordinary non-steady state one dimensional diffusion equation. (II) Rn atoms originated far from the measuring site (including Chinese Continent), which is denoted by 'background component'. For this component, we propose a one layer transport model using air mass trajectory technique. By this model we can explain well the temporal variation of back-ground component and seasonal variation of Rn at Nagoya. A numerical simulation of the temporal variation of Rn was carried out for meso-regional scale (200kmx200kmx1km). The results was compared with the continuous measurements of Rn concentration at Nagoya, and fairly good agreements was obtained. We have obtained horizontal distributions of Rn around Nagoya (150kmx150km) for each season by using a passive method. The linear relationship between Rn concentration and measured Rn exhalation rate supports the transport model mentioned above and gives us other interesting informations. (author)

  1. Radon diffusion through sandy construction materials: effect of temperature and grain size

    International Nuclear Information System (INIS)

    Narula, A.K.; Goyal, S.K.; Jain, Ravinder; Kant, Krishan; Yadav, Mani Kant; Chauhan, R.P.; Chakarvarti, S.K.

    2013-01-01

    Radon appears mainly by diffusion process from the point of origin, say, under ground soil and building materials used in construction of house following alpha decay of radium. The radon diffusion through different building construction materials can be compared by calculating radon diffusion coefficient for them. In the present work, we studied the effect of temperature and grain size on radon diffusion of coarse sand as construction material. The coarse sand was collected from Yamuna river bed, originated from Himalayas. For this study, a steel pipe of diameter 10 cm and length 30 cm., divided into four sectors of equal size, was filled in different sectors with different grain sized (800, 600 and 425 μm) sand as building construction material. A number LR-115 type-II particle track detectors were placed with inter-detector distance of 10 cm in the sectorial compartments. The bottom end of steel pipe assembly was fixed with a radon chamber containing radon source with upper end sealed with a cap. The whole arrangement was then placed into a sand-clay pipe wrapped around by a controlled heating filament, resulting into temperature variations from 25℃ to 60℃. After 100 days interval, the detectors were retrieved processed, and the α - tracks counted for the calculation of radon concentration. It is observed that the radon diffusion coefficient increases with the increase in temperature and decreases with decrease in grain size of the coarse sand. (author)

  2. Experimental Setup for Measuring Diffusive and Advective Transport of Radon through Building Materials

    NARCIS (Netherlands)

    Pal, van der M.; Graaf, van der E.R.; Meijer, de R.J.; Wit, de M.H.; Hendriks, N.A.

    2000-01-01

    This study describes an approach for measuring and modelling diffusive and advective transport of radon through building materials. The goal of these measurements and model calculations is to improve our understanding concerning the factors influencing the transport of radon through building

  3. Experimental setup for radon exposure and first diffusion studies using gamma spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Maier, Andreas, E-mail: a.maier@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt (Germany); Beek, Patrick van [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt (Germany); Technical University Darmstadt, Hochschulstraße 6, 64289 Darmstadt (Germany); Hellmund, Johannes [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt (Germany); Durante, Marco [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt (Germany); Technical University Darmstadt, Hochschulstraße 6, 64289 Darmstadt (Germany); Schardt, Dieter; Kraft, Gerhard; Fournier, Claudia [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstraße 1, 64291 Darmstadt (Germany)

    2015-11-01

    In order to measure the uptake and diffusion of {sup 222}Rn in biological material, an exposure chamber was constructed where cell cultures, biological tissues and mice can be exposed to {sup 222}Rn-activities similar to therapy conditions. After exposure, the material is transferred to a gamma spectrometer and the decay of {sup 214}Pb and {sup 214}Bi is analyzed. From the time kinetics of these decays the total amount of the initial {sup 222}Rn concentration can be calculated. In this paper the design and construction as well as first test measurements are reported.

  4. Indoor radon epidemiological study

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, E; Tomasek, L; Mueller, T [National Radiation Protection Institute, Prague (Czech Republic); Placek, V [Inst. for Expertises and Emergencies, Pribram-Kamenna (Czech Republic); Matzner, J; Heribanova, A [State Office for Nuclear Safety, Prague (Czech Republic)

    1996-12-31

    The study is a long-term prospective cohort study of lung cancer and possibility other causes of death. The study population includes inhabitants of the area, who had resided there for at three years and at least one of these between 1.1.1960 and 21.12.1989. A total of 11865 inhabitants satisfied these criteria. The cumulative exposure of each respondent is being assessed on the basis of measurements in dwellings, time spent there and estimation of previous exposure levels by a model accounting for constructional changes in buildings. One year lasting measurements of radon daughter products by integral dosimeters (Kodak film LR 115) were performed in practically all dwellings of the specified area. Radon measurements in houses in term of equilibrium concentration are compared with the results of a pilot study in Petrovice in 1990-91 which gave the stimulus for the epidemiological study. The distribution of death causes and ratio of observed (O) to expected (E) cases among collected death cases in the cohort, generally, somewhat lower ratios than one reflect the non-industrial character of the region, with the exception of lung cancer in man. The differences in the O/E ratios for lung cancer among the separate communities indicate that even in the situation of generally lower mortality, the dependence of lung cancer mortality on radon.

  5. The analysis of radon diffusion through the buildings materials

    International Nuclear Information System (INIS)

    Grujic, S.; Radukin-Kosanovic, A.; Bikit, I.; Mrdja, D.; Forkapic, S.

    2009-01-01

    Since people most of the time spent indoors it is of great importance to analyse the radon diffusion through different types of materials, in order to prevent the increase of its concentration in the interior of buildings. The paper examined six different types of materials used in construction, mainly in the insulating purposes, in order to determine the material, or a combination of appropriate type and thickness of material which have a smaller value of diffusion coefficient of radon. (author) [sr

  6. EPA's radon study results

    International Nuclear Information System (INIS)

    Dowd, R.M.

    1988-01-01

    Last winter, in cooperation with agencies in 10 states and two metropolitan area counties, EPA measured the indoor air radon concentrations of 14,000 houses, some chosen statistically at random and some by request of the homeowner. Passive measurement methodologies were used, such as exposing a charcoal canister to the air for a few days and allowing the air to migrate in to the charcoal naturally. To reduce dilution of radon by the outside air, the protocol required that the house be shut up; therefore, the study was conducted during winter. The measuring device was placed in the lowest livable area (usually the basement) of each house to maximize potential concentration. It should be noted that these procedures are generally considered to be screening tests because they result in a worst-case measurement rather than a best value. The results of these findings are presented

  7. Method for measurement of radon diffusion and solubility in solid materials

    Science.gov (United States)

    Maier, Andreas; Weber, Uli; Dickmann, Jannis; Breckow, Joachim; van Beek, Patrick; Schardt, Dieter; Kraft, Gerhard; Fournier, Claudia

    2018-02-01

    In order to study the permeation i.e. the diffusion and solubility of radon gas in biological material, a new setup was constructed and a novel analysis was applied to obtain diffusion and solubility coefficients. Thin slabs of solid materials were installed between detector housing and the surrounding radon exposure chamber of 50 Ls volume. In this setup radon can diffuse through thin test samples into a cylindrical volume of 5 mm height and 20 mm diameter and reach an α-particle detector. There the 5.49 MeV α-decay of the penetrating radon atoms is measured by a silicon surface barrier detector. The time dependent activities inside the small detector volume are recorded after injection of a known radon activity concentration into the outer chamber. Analyzing the time behavior of the integral α-activity from radon in the small vessel, both, the diffusion coefficient and solubility of the test material can be determined, based on a new mathematical model of the diffusion process concerning the special boundary conditions given by the experimental setup. These first measurements were intended as proof of concept for the detection system and the data analysis. Thin polyethylene foils (LDPE) were selected as material for the diffusion measurements and the results were in agreement with data from literature. In further measurements, we will concentrate on biological material like bone, fat and other tissues.

  8. Radon studies in Indian dwellings

    International Nuclear Information System (INIS)

    Khan, A.J.

    2000-01-01

    The indoor radon ( 222 Rn) concentration has been measured by Solid State Nuclear Track Detectors (SSNTDs) in large number of Indian dwellings. Radon concentrations were measured in different parts of the country. In the first study, radon concentrations were measured in 143 dwellings of Udaipur, Bikaner and Banswara towns of Rajasthan province. The distributions of the time-averaged indoor radon concentration in these three towns of the Rajasthan fit an approximately log normal distribution. The geometric mean (GM) values of radon concentrations in these three places were found to be 74 Bq m -3 , 46 Bq m -3 and 66 Bq m -3 with a geometric standard deviation (GSD) of 2.2, 2.2 and 2.5 respectively. In another study, radon concentrations were measured in about 150 dwellings of hilly regions of the country. The measurements were carried out in Kohima (Nagaland), Baijnath and Palampur (Himachal Pradesh). The distribution of radon concentration in Kohima dwellings was found to be approximately log normal, however, the radon distribution in Baijnath and Palampur dwellings seems to be bimodal. The GM values of the radon concentrations for 65 dwellings in Kohima and 43 dwellings in Baijnath and Palampur were 88 Bq m -3 and 134 Bq m -3 with GSD of 1.7 and 2.5 respectively. The results are discussed in detail. (author)

  9. Calibration of diffusion barrier charcoal detectors and application to radon sampling in dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Montero C, M.E.; Colmenero S, L.; Villalba, L.; Saenz P, J.; Cano J, A.; Moreno B, A.; Renteria V, M.; Herrera P, E.F. [Cento de Investigacion en Materiales Avanzados, S. C. Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua, (Mexico); Cruz G, S. De la [Facultad de Enfermeria y Nutriologia, Universidad Autonoma de Chihuahua, Av. Politecnico Nacional 2714, Chihuahua, (Mexico); Lopez M, A. [Instituto Nacional de Investigaciones Nucleares, Apartado Postal 18-1027, 11801 Mexico D.F. (Mexico)

    2003-07-01

    Some calibration conditions of diffusion barrier charcoal canister (DBCC) detectors for measuring radon concentration in air were studied. A series of functional expressions and graphs were developed to describe relationship between radon concentration in air and the activity adsorbed in DBCC, when placed in small chambers. A semi-empirical expression for the DBCC calibration was obtained, based on the detector integration time and the adsorption coefficient of radon on activated charcoal. Both, the integration time for 10 % of DBCC of the same batch, and the adsorption coefficient of radon for the activated charcoal used in these detectors, were experimentally determined. Using these values as the calibration parameters, a semi-empirical calibration function was used for the interpretation of the radon activities in the detectors used for sampling more than 200 dwellings in the major cities of the state of Chihuahua, Mexico. (Author)

  10. Calibration of diffusion barrier charcoal detectors and application to radon sampling in dwellings

    International Nuclear Information System (INIS)

    Montero C, M.E.; Colmenero S, L.; Villalba, L.; Saenz P, J.; Cano J, A.; Moreno B, A.; Renteria V, M.; Herrera P, E.F.; Cruz G, S. De la; Lopez M, A.

    2003-01-01

    Some calibration conditions of diffusion barrier charcoal canister (DBCC) detectors for measuring radon concentration in air were studied. A series of functional expressions and graphs were developed to describe relationship between radon concentration in air and the activity adsorbed in DBCC, when placed in small chambers. A semi-empirical expression for the DBCC calibration was obtained, based on the detector integration time and the adsorption coefficient of radon on activated charcoal. Both, the integration time for 10 % of DBCC of the same batch, and the adsorption coefficient of radon for the activated charcoal used in these detectors, were experimentally determined. Using these values as the calibration parameters, a semi-empirical calibration function was used for the interpretation of the radon activities in the detectors used for sampling more than 200 dwellings in the major cities of the state of Chihuahua, Mexico. (Author)

  11. Study of underground radon transport

    International Nuclear Information System (INIS)

    Csige, I.; Hakl, J.; Lenart, L.

    1990-01-01

    The soil gas radon content measurements with solid state nuclear track detectors (SSNTDs) are widely used in geoscience, for instance in uranium exploration and earthquake prediction. In these applications the radon frequently is used as a natural tracer of underground fluid transport processes. Obviously, to get the soil radon measuring method more and more effective the study of these transport processes in deeper part of the Earth is fundamental. The Track Detector Group in the Institute of Nuclear Research of the Hungarian Academy of Sciences in Debrecen has been performing environmental radon activity concentration measurements since 1977 with alpha sensitive SSNTDs. These types of measurements were initiated and widely used by the late head of the group Dr. G. Somogyi, who devoted his life to better understanding of the nature. The measurements in caves, springs and drilled wells proved to be effective to study these underground radon transport processes. We are glad to present some results of our investigations. 7 refs, 7 figs

  12. Measurement of exhalation and diffusion parameters of radon in solids by plastic track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, G.; Haffez, A.-F.; Hunyadi, I.; Toth-Szilagyi, M.

    1986-01-01

    There are large discrepancies in data available in the literature for the exhalation and diffusion behaviour of radon in various materials. Therefore there is a need for more studies in this field. For this purpose we have developed and used track methods to measure mass and areal exhalation rates of radon from different fly ashes and sand. In addition, methods were also developed to determine the diffusion length of radon and the porosity of materials. For getting the radon emanation coefficient we have applied the autoradiographic method and the ''can-technique'' for determining the real and effective radium contents. The disturbing effect expected from the geometry of measuring cans and samples is discussed. Relations are derived for the correction of such effect.

  13. Study on radon geological potential of Beijing city

    International Nuclear Information System (INIS)

    Liu Qingcheng; Wu Xinmin; Liu Yujuan; Yang Yaxin; Zhang Ye

    2009-01-01

    According to elemental geochemistry in Beijing, the uranium content in the area was measured, and distribution of radon concentration was predicted. Based on the uranium-radium equilibrium coefficient, porosity and diffusion coefficient, which were either measured or calculated, the radon geological potential of Beijing city was studied using γ-ray spectroscopy or mass spectroscopy and certain models were used to calculate the relation between radon geological potential and lithology and geological structure. The results showed that radon geological potential of Beijing city could be divided into four zones, tend of every zone coincides with the main structure, and the potential values nearly relate with geological factors. (authors)

  14. Evaluation of diffusion parameters of radon in porous material by flow-through diffusion experiment

    International Nuclear Information System (INIS)

    Chunnan Hsu; Shihchin Tsai; Shihming Liang

    1994-01-01

    The effectiveness of a material in reducing the fluence rate of Rn from soil was assessed in this study by using a flow-through diffusion experiment to evaluate the diffusion parameters -apparent diffusion coefficient and capacity factor - of radon (Rn) in a porous material. An improved method based on the nonlinear least-squares and Marquardt's method (NLSM method) was proposed to provide more reliable analyses of experimental data than the graphical method. The NLSM method was confirmed by the experimental results to be capable of estimating the diffusion parameters, even if the process was transient. This method was also demonstrated to correlate sufficiently with the results by the conventional method while the process had already reached steady-state. Natural mordenite was employed in this study as a testing material because it has more effective sorption for noble gas than any other earthen material. (author)

  15. Radon in soils: intercomparative studies

    International Nuclear Information System (INIS)

    Segovia, N.; Galle, C.; Seidel, J.-L.; Monnin, M.

    1988-01-01

    Two kinds of experiments were designed to evaluate some of the variations that can be expected from radon in soil concentrations as monitored by closely spaced solid state nuclear track detectors (SSNTDs). Measurements were performed by the Insituto Nacional de Investigations Nucleares in Mexico and the Laboratoire de Physique Corpusculaire in France. The first experimental design consisted of a series of 15 day exposures of twenty monitoring devices placed inside a single bore hole. Fluctuations obtained in the radon levels at the twenty closely spaced monitoring sites ranged from 9% to 33%. The second experiment was performed with 4 pairs of radon monitoring devices located at 4 different sites at the summit of the Nevado de Toluca volcano. Results show that the SSNTD technique is well suited for radon measurements intended for geophysical studies. (author)

  16. Radon in soils: intercomparative studies

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, N.; Galle, C. (Instituto Nacional de Investigaciones Nucleares, Mexico City (Mexico)); Seidel, J.-L.; Monnin, M. (Clermont-Ferrand-2 Univ., 63 - Aubiere (France). Lab. de Physique Corpusculaire)

    1988-01-01

    Two kinds of experiments were designed to evaluate some of the variations that can be expected from radon in soil concentrations as monitored by closely spaced solid state nuclear track detectors (SSNTDs). Measurements were performed by the Insituto Nacional de Investigations Nucleares in Mexico and the Laboratoire de Physique Corpusculaire in France. The first experimental design consisted of a series of 15 day exposures of twenty monitoring devices placed inside a single bore hole. Fluctuations obtained in the radon levels at the twenty closely spaced monitoring sites ranged from 9% to 33%. The second experiment was performed with 4 pairs of radon monitoring devices located at 4 different sites at the summit of the Nevado de Toluca volcano. Results show that the SSNTD technique is well suited for radon measurements intended for geophysical studies. (author).

  17. Diffusion coefficients of decay products of radon and thoron

    International Nuclear Information System (INIS)

    Raghunath, B.; Kotrappa, P.

    1979-01-01

    The diffusion coefficients of the decay products of radon and thoron have relevance in the evaluation of inhalation hazards in uranium and thorium processing industries. A recently developed diffusion sampler, based on Mercer's theory of diffusional deposition between the concentric circular plates, has been used for determining the diffusion coefficients of the unattached decay products of radon and thoron (RaA, RaB, RaC and ThB). Experiments were conducted at different ventilation rates (6 and 60 changes/hr) at different relative humidities (10 and 90%) and both in air and argon atmospheres. Diffusion coefficients were found to increase with increasing ventilation rates and were found to decrease at higher relative humidities, the effect being more marked at lower ventilation rates. Both of these effects were less pronounced in argon than in air. Results are discussed in light of the known properties of these decay products. (author)

  18. Diffusion of radon through varying depths of cement

    International Nuclear Information System (INIS)

    Takriti, S.; Shweikani, R.; Ali, A.F.; Hushari, M.; Kheitou, M.

    2001-01-01

    Portland cement was mixed with different concentrations of radium chloride (1200, 2400 and 3600 Bq) to produce radioactive sources. These sources were surrounded with cement of different thickness (1, 2 and 4 cm). The release of radon from these sources (before and after being surrounded) was studied. The results showed that radon release from the sources itself was less then its release from the same source after being surrounded by cement, and the release did not change with the thickness of cement. Samples were covered with a thin layer of polyethylene before being surrounded with cement. It was found that this additional layer reduced the radon exhalation. This thin layer stopped any reaction between the source and the surrounding cement during solidification of the cement layers. These reactions are thought to be the reason for the increase of radon exhalation from the sources surrounded by cement

  19. Radon progeny distribution in cylindrical diffusion chambers

    International Nuclear Information System (INIS)

    Pressyanov, Dobromir S.

    2008-01-01

    An algorithm to model the diffusion of radioactive decay chain atoms is presented. Exact mathematical solutions in cylindrical geometry are given. They are used to obtain expressions for the concentrations of 222 Rn progeny atoms in the volume and deposited on the wall surface in cylindrical diffusion chambers. The dependence of volume fractions of 222 Rn progeny and chamber sensitivity on the coefficient of diffusion of 222 Rn progeny atoms in air is modeled.

  20. Radon diffusion in candidate soils for covering uranium mill tailings

    International Nuclear Information System (INIS)

    Silker, W.B.; Kalkwarf, D.R.

    1983-04-01

    Diffusion coefficients were measured for radon in 34 soils that had been identified by mill personnel as candidate covers for their tailings piles in order to reduce radon emission. These coefficients referred to diffusion in the total pore space of the soils. They were measured in the laboratory by a steady-state method using soil columns compacted to greater than 80% of their Proctor maximum packing densities but with moisture contents generally less than would be expected at a tailings site. An empirical equation was used to extrapolate measured coefficients to value expected at soil-moisture contents representative of tailings sites in the western United States. Extrapolated values for silty sands and clayey sands ranged from 0.004 to 0.06 cm 2 /s. Values for inorganic silts and clays ranged from 0.001 to 0.02 cm 2 /s

  1. Numerical and analytical assessment of radon diffusion in various media and potential of charcoal as radon detector

    Science.gov (United States)

    Rybalkin, Andrey

    Numerical assessments of radon diffusion together with analytical estimates for short-time and long-time exposure were the first objective of this thesis with the goal to demonstrate how radon propagates in various media. Theoretical predictions were compared to numerical simulations, and obtained values of total radon activities inside each material match quite well with the analytical estimates. These estimates, for activated and nonactivated charcoal, were then used to evaluate the possibility of designing a charcoal system to be used as a radon detector. Another objective was to use nonactivated charcoal samples and measure the level of radon accumulation, and use these data to estimate radon diffusion and adsorption coefficients. The analytical approach was developed to estimate these values. Radon adsorption coefficient in nonactivated charcoal was found to be from 0.2 to 0.4 m3/kg. Radon diffusion coefficient for nonactivated charcoal is in the range of 1.2×10-11 to 5.1×10-10 m2/s in comparison to activated charcoal with adsorption coefficient of 4 m3/kg and diffusion coefficient of 1.43×10-9 m2/s. The third objective was to use GEANT4 numerical code to simulate decay of 238U series and 222Rn in an arbitrary soil sample. Based on that model, the goal was to provide a guideline for merging GEANT4 radioactive decay modeling with the diffusion of radon in a soil sample. It is known that radon can be used as an earthquake predictor by measuring its concentration in groundwater, or if possible, along the faults. Numerical simulations of radon migration by diffusion only were made to estimate how fast and how far radon can move along the fault strands. Among the known cases of successful correlations between radon concentration anomalies and earthquake are the 1966 Tashkent and 1976 Songpan-Pingwu earthquakes. Thus, an idea of radon monitoring along the Wasatch Fault, using system of activated/nonactivated charcoals together with solid state radon detectors is

  2. Effective diffusion coefficient of radon in concrete, theory and method for field measurements

    International Nuclear Information System (INIS)

    Culot, M.V.J.; Olson, H.G.; Schiager, K.J.

    1976-01-01

    A linear diffusion model serves as the basis for determination of an effective radon diffusion coefficient in concrete. The coefficient was needed to later allow quantitative prediction of radon accumulation within and behind concrete walls after application of an impervious radon barrier. A resolution of certain discrepancies noted in the literature in the use of an effective diffusion coefficient to model diffusion of a radioactive gas through a porous medium is suggested. An outline of factors expected to affect the concrete physical structure and the effective diffusion coefficient of radon through it is also presented. Finally, a field method for evaluating effective radon diffusion coefficients in concrete is proposed and results of measurements performed on a concrete foundation wall are compared with similar published values of gas diffusion coefficients in concrete. (author)

  3. Modelling uncertainties in the diffusion-advection equation for radon transport in soil using interval arithmetic.

    Science.gov (United States)

    Chakraverty, S; Sahoo, B K; Rao, T D; Karunakar, P; Sapra, B K

    2018-02-01

    Modelling radon transport in the earth crust is a useful tool to investigate the changes in the geo-physical processes prior to earthquake event. Radon transport is modeled generally through the deterministic advection-diffusion equation. However, in order to determine the magnitudes of parameters governing these processes from experimental measurements, it is necessary to investigate the role of uncertainties in these parameters. Present paper investigates this aspect by combining the concept of interval uncertainties in transport parameters such as soil diffusivity, advection velocity etc, occurring in the radon transport equation as applied to soil matrix. The predictions made with interval arithmetic have been compared and discussed with the results of classical deterministic model. The practical applicability of the model is demonstrated through a case study involving radon flux measurements at the soil surface with an accumulator deployed in steady-state mode. It is possible to detect the presence of very low levels of advection processes by applying uncertainty bounds on the variations in the observed concentration data in the accumulator. The results are further discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Experimental and theoretical study of radon levels in a house

    International Nuclear Information System (INIS)

    Ameon, R.; Dupuis, M.; Marie, L.; Diez, O.; LionS, J.; Tymen, G.

    2006-01-01

    Full text of publication follows: Radon being a radioactive gas of natural origin is omnipresent everywhere at the surface of earth. It is created by the radium decay issued from the uranium contained in the earth crust and more specifically in granitic and volcanic subsoils. Because of the dilution due to air masses, its concentration in open air is low. On the other hand, radon may accumulate in the confined atmosphere of buildings and achieve high concentration levels. Across France, it has been estimated that 300 000 individual dwellings present concentration higher than the French reference level of 400 Bq.m -3 and that 60 000 other ones would exhibit concentration above 1 000 Bq.m -3 , the French warning threshold. Indoor radon concentration may vary significantly for various reasons, including design of buildings, radium content and texture of the soil in contact with the building's slab and walls, the under pressure value between the inside and outside and the fresh air supply rate. These considerations have led the I.R.S.N. to develop a code called R.A.D.O.N. 2 for conducting simple and methodical studies of indoor radon concentrations, to take into account the above-mentioned factors. But, the achievement of an effective diagnosis and risk management -aiding tool requires to first check its validity on the phenomenological model at the origin of the code. A 3-year experimental follow-up was, thus, conducted within an unoccupied house built on an uranium-bearing geological formation. After characterization of the subsoil, the instrumentation was implemented on site to continuously monitor the following parameters: - the radon source term in the building (exhalation rate of 222 Rn at the ground/building interface and at soil surface, radon concentration at the soil and in outdoor air), - the radon penetration by advection (differential pressure in the house basement), - the driving mechanisms for natural ventilation in the house (weather conditions, indoor

  5. Experimental and theoretical study of radon levels in a house

    Energy Technology Data Exchange (ETDEWEB)

    Ameon, R.; Dupuis, M.; Marie, L.; Diez, O.; LionS, J. [Institute for Radiological Protection and Nuclear Safety, Fontenay-aux-roses (France); Tymen, G. [LARAAH, Universite de Bretagne Occidentale, Brest (France)

    2006-07-01

    Full text of publication follows: Radon being a radioactive gas of natural origin is omnipresent everywhere at the surface of earth. It is created by the radium decay issued from the uranium contained in the earth crust and more specifically in granitic and volcanic subsoils. Because of the dilution due to air masses, its concentration in open air is low. On the other hand, radon may accumulate in the confined atmosphere of buildings and achieve high concentration levels. Across France, it has been estimated that 300 000 individual dwellings present concentration higher than the French reference level of 400 Bq.m{sup -3} and that 60 000 other ones would exhibit concentration above 1 000 Bq.m{sup -3}, the French warning threshold. Indoor radon concentration may vary significantly for various reasons, including design of buildings, radium content and texture of the soil in contact with the building's slab and walls, the under pressure value between the inside and outside and the fresh air supply rate. These considerations have led the I.R.S.N. to develop a code called R.A.D.O.N. 2 for conducting simple and methodical studies of indoor radon concentrations, to take into account the above-mentioned factors. But, the achievement of an effective diagnosis and risk management -aiding tool requires to first check its validity on the phenomenological model at the origin of the code. A 3-year experimental follow-up was, thus, conducted within an unoccupied house built on an uranium-bearing geological formation. After characterization of the subsoil, the instrumentation was implemented on site to continuously monitor the following parameters: - the radon source term in the building (exhalation rate of {sup 222}Rn at the ground/building interface and at soil surface, radon concentration at the soil and in outdoor air), - the radon penetration by advection (differential pressure in the house basement), - the driving mechanisms for natural ventilation in the house (weather

  6. Czech studies of lung cancer and radon

    International Nuclear Information System (INIS)

    Tomasek, L.

    2002-01-01

    According to the International Agency for Research on Cancer, there is a significant evidence to classify radon as a carcinogen. Using extrapolations from occupational studies, it can be shown that for some countries environmental exposure to radon is the second most important cause of lung cancer in the general population after cigarette smoking. Czech studies among uranium miners, established in 1970 by Josef Sevc, and in the general population aim to contribute to knowledge on the risk from radon, particularly by evaluating temporal factors and interaction of radon exposure and smoking

  7. Low-Cost Radon Reduction Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Rose, William B. [Partnership for Advanced Residential Retrofit, Champaign, IL (United States); Francisco, Paul W. [Partnership for Advanced Residential Retrofit, Champaign, IL (United States); Merrin, Zachary [Partnership for Advanced Residential Retrofit, Champaign, IL (United States)

    2015-09-01

    The aim of the research was to conduct a primary scoping study on the impact of air sealing between the foundation and the living space on radon transport reduction across the foundation-living space floor assembly. Fifteen homes in the Champaign, Illinois area participated in the study. These homes were instrumented for hourly continuous radon measurements and simultaneous temperature and humidity the foundation was improved. However, this improved isolation did not lead to significant reductions in radon concentration in the living space. Other factors such as outdoor temperature were shown to have an impact on radon concentration.

  8. Semi-empirical approach for calibration of CR-39 detectors in diffusion chambers for radon measurements

    Energy Technology Data Exchange (ETDEWEB)

    Pereyra A, P.; Lopez H, M. E. [Pontificia Universidad Catolica del Peru, Av. Universitaria 1801, San Miguel Lima 32 (Peru); Palacios F, D.; Sajo B, L. [Universidad Simon Bolivar, Laboratorio de Fisica Nuclear, Apartado 89000 Caracas (Venezuela, Bolivarian Republic of); Valdivia, P., E-mail: ppereyr@pucp.edu.pe [Universidad Nacional de Ingenieria, Av. Tupac Amaru s/n, Rimac, Lima 25 (Peru)

    2016-10-15

    Simulated and measured calibration of PADC detectors is given for cylindrical diffusion chambers employed in environmental radon measurements. The method is based on determining the minimum alpha energy (E{sub min}), average critical angle (<Θ{sub c}>), and fraction of {sup 218}Po atoms; the volume of the chamber (f{sub 1}), are compared to commercially available devices. Radon concentration for exposed detectors is obtained from induced track densities and the well-established calibration coefficient for NRPB monitor. Calibration coefficient of a PADC detector in a cylindrical diffusion chamber of any size is determined under the same chemical etching conditions and track analysis methodology. In this study the results of numerical examples and comparison between experimental calibration coefficients and simulation purpose made code. Results show that the developed method is applicable when uncertainties of 10% are acceptable. (Author)

  9. Semi-empirical approach for calibration of CR-39 detectors in diffusion chambers for radon measurements

    International Nuclear Information System (INIS)

    Pereyra A, P.; Lopez H, M. E.; Palacios F, D.; Sajo B, L.; Valdivia, P.

    2016-10-01

    Simulated and measured calibration of PADC detectors is given for cylindrical diffusion chambers employed in environmental radon measurements. The method is based on determining the minimum alpha energy (E min ), average critical angle (<Θ c >), and fraction of 218 Po atoms; the volume of the chamber (f 1 ), are compared to commercially available devices. Radon concentration for exposed detectors is obtained from induced track densities and the well-established calibration coefficient for NRPB monitor. Calibration coefficient of a PADC detector in a cylindrical diffusion chamber of any size is determined under the same chemical etching conditions and track analysis methodology. In this study the results of numerical examples and comparison between experimental calibration coefficients and simulation purpose made code. Results show that the developed method is applicable when uncertainties of 10% are acceptable. (Author)

  10. Radon

    Science.gov (United States)

    ... radon-resistant features. These features include gravel and plastic sheeting below the foundation, along with proper sealing ... lower the radon level. Detailed information about radon reduction in your home or building can be found ...

  11. Comparison of radon diffusion coefficients measured by transient-diffusion and steady-state laboratory methods

    International Nuclear Information System (INIS)

    Kalwarf, D.R.; Nielson, K.K.; Rich, D.C.; Rogers, V.C.

    1982-11-01

    A method was developed and used to determine radon diffusion coefficients in compacted soils by transient-diffusion measurements. A relative standard deviation of 12% was observed in repeated measurements with a dry soil by the transient-diffusion method, and a 40% uncertainty was determined for moistures exceeding 50% of saturation. Excellent agreement was also obtained between values of the diffusion coefficient for radon in air, as measured by the transient-diffusion method, and those in the published literature. Good agreement was also obtained with diffusion coefficients measured by a steady-state method on the same soils. The agreement was best at low moistures, averaging less than ten percent difference, but differences of up to a factor of two were observed at high moistures. The comparison of the transient-diffusion and steady-state methods at low moistures provides an excellent verification of the theoretical validity and technical accuracy of these approaches, which are based on completely independent experimental conditions, measurement methods and mathematical interpretations

  12. New method and installation for rapid determination of radon diffusion coefficient in various materials.

    Science.gov (United States)

    Tsapalov, Andrey; Gulabyants, Loren; Livshits, Mihail; Kovler, Konstantin

    2014-04-01

    The mathematical apparatus and the experimental installation for the rapid determination of radon diffusion coefficient in various materials are developed. The single test lasts not longer than 18 h and allows testing numerous materials, such as gaseous and liquid media, as well as soil, concrete and radon-proof membranes, in which diffusion coefficient of radon may vary in an extremely wide range, from 1·10(-12) to 5·10(-5) m(2)/s. The uncertainty of radon diffusion coefficient estimation depends on the permeability of the sample and varies from about 5% (for the most permeable materials) to 40% (for less permeable materials, such as radon-proof membranes). Copyright © 2014. Published by Elsevier Ltd.

  13. Effects of radon in indoor air studied

    International Nuclear Information System (INIS)

    Auvinen, A.

    1994-01-01

    Radon is an odorless, tasteless and colourless radioactive noble gas that enters indoor air from the ground. Radon causes lung cancer. A committee set up to evaluate the health risks of chemical substances has been drafting a report on radon, which will compile the major research findings on the lung cancer risk posed by radon. Animal tests have shown that even small doses of radon can cause lung cancer. Smokers seem to contract radon-induced lung cancer more readily than non-smokers. Because research findings have been conflicting, however, it is not known exactly how high the risk of lung cancer caused by indoor radon exposure really is. Several major research projects are under way to obtain increasingly accurate risk assessments. An on-going European joint project brings together several studies - some already finished, some still being worked on. In this way it will be possible to get more accurate risk assessments than from individual studies. In order to prevent lung cancer, it is important to continue the work of determining and reducing radon connects and to combat smoking. (orig.)

  14. Diffusive transport of radon in a homogeneous column of dry sand

    NARCIS (Netherlands)

    van der Spoel, W.H.; van der Graaf, E.R.; de Meijer, R.J.

    To validate a model for radon transport in soil, measurements of diffusive radon transport under well-defined and controlled conditions have been made in a homogeneous column of dry sand with an air-filled volume on top. This volume simulates a crawl space. The measurements concern time-dependent

  15. New method and installation for rapid determination of radon diffusion coefficient in various materials

    International Nuclear Information System (INIS)

    Tsapalov, Andrey; Gulabyants, Loren; Livshits, Mihail; Kovler, Konstantin

    2014-01-01

    The mathematical apparatus and the experimental installation for the rapid determination of radon diffusion coefficient in various materials are developed. The single test lasts not longer than 18 h and allows testing numerous materials, such as gaseous and liquid media, as well as soil, concrete and radon-proof membranes, in which diffusion coefficient of radon may vary in an extremely wide range, from 1·10 −12 to 5·10 −5 m 2 /s. The uncertainty of radon diffusion coefficient estimation depends on the permeability of the sample and varies from about 5% (for the most permeable materials) to 40% (for less permeable materials, such as radon-proof membranes). - Highlights: • The new method and installation for determination of radon diffusion coefficient D are developed. • The measured D-values vary in an extremely wide range, from 5×10 -5 to 1×10 -12 m 2 /s. • The materials include water, air, soil, building materials and radon-proof membranes. • The duration of the single test does not exceed 18 hours. • The measurement uncertainty varies from 5% (in permeable materials) to 40% (in radon gas barriers)

  16. Two new methods of determining radon diffusion in fish otoliths

    International Nuclear Information System (INIS)

    Whitehead, N.E.; Ditchburn, R.G.

    1995-01-01

    Otoliths are bony structures found in the ears of fish and used in the 210 Pb/ 226 Ra dating method for age determination. This paper checks the assumption that 222 Rn is not lost from or added to orange roughy fish otoliths by diffusion, which would invalidate the technique. The first method of monitoring diffusion relies on measuring the gamma activity of daughter radionuclides. Otoliths were exposed to an atmosphere enriched in 222 Rn for 10 days, and the supported gamma activity inside them measured allowing for various decay corrections. The calculated radon addition was (0.5 ±0.5)% of the activity of the 226 Ra present. The second method used an alpha spectrometer and attempted to detect 222 Rn directly outguessed from otoliths in the detector vacuum chamber. The results were consistent within errors with those of the first method and showed no loss or gain of 222 Rn, supporting previous estimates of a long life-span for the orange rough y. In contrast it was found that approximately 10% of 222 Rn formed in orange roughy fish scales was lost to an evacuated environment, (hence perhaps to an aqueous environment) and that for this species it could be difficult to base a dating method on analysis of scales. Nevertheless a preliminary minimum age of 57 years was obtained. The methods could be used with non-biological samples to determine 222 Rn diffusion rates. (author). 17 refs., 5 figs

  17. Radon as a natural geochemical tracer for study of groundwater discharge into lakes

    International Nuclear Information System (INIS)

    Schmidt, Axel

    2008-01-01

    In the presented work the suitability of the naturally occurring radioactive noble gas isotope radon-222 for qualitative and quantitative description of groundwater discharge into lakes was studied. Basis of these investigations was the development of two innovative techniques for the on-site determination of radon in water. In the ex-situ radon measurement procedure, water from the source concerned is taken up in an exchange cell used for this purpose. Inside this cell, the radon dissolved in water is transferred via diffusion into a closed counter-flow of air and subsequently detected by a radon-in-air monitor. Where the in-situ radon determination is concerned, a module composed of a semipermeable membrane is introduced into a water column. Subsequently, the radon dissolved in the water body diffuses through the membrane into the corresponding air flow, by means of which it is transferred into a radon-in-air monitor and is detected. Combination of the developed mobile radon extraction techniques with a suitable and portable radon monitor allow the detection of radon-222 with sufficient accuracy (smaller 20 %) in groundwater as well as in surface waters, i.e., within a broad range of concentrations. Radon-222 was subsequently used to characterize groundwater discharge into a meromictic and a dimictic lake, i.e. two types of lake basically distinct from each other with respect to their water circulation properties were investigated. The use of the noble gas isotope radon-222 as a geochemical tracer makes the application of on-site detection techniques possible and that this in turn permits a rapid, reliable, and cost-effective assessment of groundwater discharge rates into lake water bodies

  18. Radon as a natural geochemical tracer for study of groundwater discharge into lakes

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Axel

    2008-06-27

    In the presented work the suitability of the naturally occurring radioactive noble gas isotope radon-222 for qualitative and quantitative description of groundwater discharge into lakes was studied. Basis of these investigations was the development of two innovative techniques for the on-site determination of radon in water. In the ex-situ radon measurement procedure, water from the source concerned is taken up in an exchange cell used for this purpose. Inside this cell, the radon dissolved in water is transferred via diffusion into a closed counter-flow of air and subsequently detected by a radon-in-air monitor. Where the in-situ radon determination is concerned, a module composed of a semipermeable membrane is introduced into a water column. Subsequently, the radon dissolved in the water body diffuses through the membrane into the corresponding air flow, by means of which it is transferred into a radon-in-air monitor and is detected. Combination of the developed mobile radon extraction techniques with a suitable and portable radon monitor allow the detection of radon-222 with sufficient accuracy (smaller 20 %) in groundwater as well as in surface waters, i.e., within a broad range of concentrations. Radon-222 was subsequently used to characterize groundwater discharge into a meromictic and a dimictic lake, i.e. two types of lake basically distinct from each other with respect to their water circulation properties were investigated. The use of the noble gas isotope radon-222 as a geochemical tracer makes the application of on-site detection techniques possible and that this in turn permits a rapid, reliable, and cost-effective assessment of groundwater discharge rates into lake water bodies.

  19. Comparative study of radon in Sudan

    International Nuclear Information System (INIS)

    Gharbi, Shaza Ismail Mohammed

    2014-07-01

    This study was conducted primarily to contribute radon data for radon map in Sudan and identify regions with elevated radon levels and improve data collection and analysis for the future radon levels evaluation. This study partially covered three states of Sudan ( Red Sea - Khartoum - South Khordofan). Previous work done has been considered in this study which focused and investigated the levels of radon concentration in ( indoor radon gas and water) by using gamma spectrometry equipped with ( HPGe detector) or (Na1 (T1) detector). The results obtained are within the acceptable levels and dose not poses any risk from radiation protection point of view. Red Sea state ( port-sudan): (124.39±6.21) Bq/m 3 . Khartoum state ( Suba): (151.52) Bq/m 3 . (Omdurman): ( 127±23) Bq/m 3 . Radon in water: (59) Bq/L. South Kordofan State: (102.8) Bq/m 3 . In water (Kadugli): (3 1 39)) Bq/L.(Author)

  20. A study of radon 222 transfer indoors

    International Nuclear Information System (INIS)

    Maximilien, R.; Robe, M.C.; Archimbaud, M.

    1985-01-01

    Indoor exposure can vary considerably depending upon the natural environment (geology, climate), man-made arrangements (building materials, insulation and ventilation systems...) or way of living. In order to specify the sources and assess their respective contribution in a given dwelling, a good knowledge of radon transfer and dispersion processes is required as well as a heavy experimental device (continuous radon and ventilation monitoring...). The study must be limited to some cases selected by a systematic measurement program either because they are representative of dwelling conditions, or preferably on account of their high radon level, the origin of which will be investigated. As a consequence, countermeasures can be developed. A pilot study has been carried out on radon transport in two houses of the Rhone river valley. The two houses -selected among 131 other ones for their high radon levels- are built with the same architectural approach and located very close to each other, yet the factors accounting for domestic exposure are quite different. Indoor parameters are at the origin of various radon concentrations in the case of low natural ventilation; conversely, outdoor parameters only seem to act in the case of high ventilation. For a larger part, however, radon seems to emanate from under the foundations of both houses [fr

  1. Temporal signatures of advective versus diffusive radon transport at a geothermal zone in Central Nepal

    International Nuclear Information System (INIS)

    Richon, Patrick; Perrier, Frederic; Koirala, Bharat Prasad; Girault, Frederic; Bhattarai, Mukunda; Sapkota, Soma Nath

    2011-01-01

    Temporal variation of radon-222 concentration was studied at the Syabru-Bensi hot springs, located on the Main Central Thrust zone in Central Nepal. This site is characterized by several carbon dioxide discharges having maximum fluxes larger than 10 kg m -2 d -1 . Radon concentration was monitored with autonomous Barasol TM probes between January 2008 and November 2009 in two small natural cavities with high CO 2 concentration and at six locations in the soil: four points having a high flux, and two background reference points. At the reference points, dominated by radon diffusion, radon concentration was stable from January to May, with mean values of 22 ± 6.9 and 37 ± 5.5 kBq m -3 , but was affected by a large increase, of about a factor of 2 and 1.6, respectively, during the monsoon season from June to September. At the points dominated by CO 2 advection, by contrast, radon concentration showed higher mean values 39.0 ± 2.6 to 78 ± 1.4 kBq m -3 , remarkably stable throughout the year with small long-term variation, including a possible modulation of period around 6 months. A significant difference between the diffusion dominated reference points and the advection-dominated points also emerged when studying the diurnal S 1 and semi-diurnal S 2 periodic components. At the advection-dominated points, radon concentration did not exhibit S 1 or S 2 components. At the reference points, however, the S 2 component, associated with barometric tide, could be identified during the dry season, but only when the probe was installed at shallow depth. The S 1 component, associated with thermal and possibly barometric diurnal forcing, was systematically observed, especially during monsoon season. The remarkable short-term and long-term temporal stability of the radon concentration at the advection-dominated points, which suggests a strong pressure source at depth, may be an important asset to detect possible temporal variations associated with the seismic cycle. - Graphical

  2. Laboratory measurements of radon diffusion through multilayered cover systems for uranium tailings

    International Nuclear Information System (INIS)

    Nielson, K.K.; Rogers, V.C.; Rich, D.C.; Nederhand, F.A.; Sandquist, G.M.; Jensen, C.M.

    1981-12-01

    Laboratory measurements of radon fluxes and radon concentration profiles were conducted to characterize the effectiveness of multilayer cover systems for uranium tailings. The cover systems utilized soil and clay materials from proposed disposal sites for the Vitro, Durango, Shiprock, Grand Junction and Riverton tailings piles. Measured radon fluxes were in reasonable agreement with values predicted by multilayer diffusion theory. Results obtained by using air-filled porosities in the diffusion calculations were similar to those obtained by using total porosities. Measured diffusion coefficients were a better basis for predicting radon fluxes than were correlations of diffusion coefficient with moisture or with air porosity. Radon concentration profiles were also fitted by equations for multilayer diffusion in the air-filled space. Layer-order effects in the multilayer cover systems were examined and estimated to amount to 10 to 20 percent for the systems tested. Quality control measurements in support of the multilayer diffusion tests indicated that moisture absorption was not a significant problem in radon flux sampling with charcoal canisters, but that the geometry of the sampler was critical. The geometric design of flux-can samplers was also shown to be important. Enhanced radon diffusion along the walls of the test columns was examined and was found to be insignificant except when the columns had been physically disturbed. Additional moisture injected into two test columns decreased the radon flux, as expected, but appeared to migrate into surrounding materials or to be lost by evaporation. Control of moisture content and compaction in the test columns appeared to be the critical item affecting the accuracies of the experiments

  3. Radon

    International Nuclear Information System (INIS)

    1990-01-01

    This leaflet in the At-a-Glance Series, describes what radon is, where it is found, why it presents a risk to health, the official advice, and the remedies that are available to reduce radon levels. (author)

  4. Radon measurement studies in Kazakhstan

    International Nuclear Information System (INIS)

    Sevost'yanov, V.N.

    2003-01-01

    Today, one has to admit that despite the important role and certain achievements in providing the radiation control in Kazakhstan, radon measurements still present some problems related to clear definition of physical quantities applied, correct use of methods, and application of adequate measuring devices to meet requirements of regulatory documents currently in effect, such as NRB-99. The paper provides some data on radon measurements, describes the problem status in Kazakhstan and proposes ways to solve it. (author)

  5. A Radon Micro Study of Salthill, Galway

    International Nuclear Information System (INIS)

    Boyle-Tobin Ann

    2006-01-01

    This project presents a study of radon gas, when it enters from the ground into the built environment. In order to further inform the present body of knowledge on this potentially dangerous gas, a radon micro study is carried out in the area of Salthill, Galway. A total of 51 households are measured for radon. The results indicate a high variation in the levels recorded, with over a third of the houses measuring above the national safe standard of 200 becquerels per cubic meter, with a small percentage of houses exhibiting very high levels. The results are spatially analysed against the local geology, as radon is a by-product of the breakdown of uranium in rocks. Householders' knowledge and awareness of radon is explored to inform the reasons why more people are not testing their homes for radon, and not installing remedial measures when high levels are detected. The findings indicate significant gaps in householders' knowledge of radon. A certain complacency is noted, which may indicate that people still do not recognise a need to know about this invisible threat. As ways to encourage further testing and remediation levels are equally explored, the government is viewed to play a central role in these processes through partial state funding. Further evidence supports continued and more effective and widespread advertising of radon issues, through all types of media, with emphasis at local level. Incidents of lung cancer and lung disease of long term residents are recorded in an attempt to find out if there is a correlation between them. The results indicate no correlation; however, not all households could participate in this part of the survey as it was limited to long-term residents only

  6. Influence of radon diffusion on the 210Pb distribution in sediments

    International Nuclear Information System (INIS)

    Imboden, D.M.; Stiller, M.

    1982-01-01

    A mathematical model is presented which describes the distribution of radon 222 in sediments having a constant or variable depth distribution of radium 226. The model is extended to the distribution of lead 210, taking into account the mobility of radon (the precursor of 210 Pb) within the sediment column. The 210 Pb model is compared, at constant radium activity, with the conventional approach which disregards the radon diffusion when estimating sedimentation rates by the 210 Pb method. The ratio between apparent and real sedimentation rate, s'/s, expressed as a function of three dimensionless parameters, demonstrates the importance of the radon diffusion effect. This effect is particularly important for sediments with small initial excess 210 Pb activity, small sedimentation rate, large radon diffusivity, or a combination of these factors. Applied to Lake Geneva, the sedimentation is estimated to be larger by 30--50% than the original value by Krishnaswami et al, (1971). In sediments which are mixed at the surface (physical mixing or bioturbation), the 210 PB activity in the mixed layer is diminished compared to that in the settling sediment material (Robbins et al., 1977), and radon diffusion makes the activity difference even larger, especially for low initial excess 210 Pb activity, small sedimentation rate, and large mixing intensity. This result may be of importance for the balance of 210 Pb in an aquatic system if the calculations are based on activities measured in the sediment

  7. Radon studies in selected workplaces

    International Nuclear Information System (INIS)

    Randle, M.W.

    2000-01-01

    Radon progeny levels were measured in coal mines, a hard rock mine and two underground hydro power stations, to indicate if there is a health problem associated with exposure to radon and radon progeny in these workplaces. The average alpha concentrations ranged from 37 to 276 Bq m -3 , with the highest levels being found in a mine with no ventillation that was being decommissioned. Average dosages were calculated to be 0.1 - 0.7 mSv y -1 . Radon progeny levels in coal mines measured in the return air circuit are indicative of levels to which a worker at the face would be exposed. They were well below international guidelines for intervention in New Zealand mines, as were the slightly higher levels in two underground hydro power stations. These results confirm that radon levels in New Zealand are low. Even in the extreme situation represented by the Sullivan mine with no ventillation the levels do not warrant concern. 11 refs., 2 tabs

  8. IN-SITU MEASURING METHOD OF RADON AND THORON DIFFUSION COEFFICIENT IN SOIL

    Directory of Open Access Journals (Sweden)

    V.S. Yakovleva

    2014-06-01

    Full Text Available A simple and valid in-situ measurement method of effective diffusion coefficient of radon and thoron in soil and other porous materials was designed. The analysis of numerical investigation of radon and thoron transport in upper layers of soil revealed that thoron flux density from the earth surface does not depend on soil gas advective velocity and varies only with diffusion coefficient changes. This result showed the advantages of thoron using versus radon using in the suggested method. The comparison of the new method with existing ones previously developed. The method could be helpful for solving of problems of radon mass-transport in porous media and gaseous exchange between soil and atmosphere.

  9. Radon

    Energy Technology Data Exchange (ETDEWEB)

    Weigel, F [Muenchen Univ. (Germany, F.R.). Inst. fuer Anorganische Chemie

    1978-09-01

    The noble gas radon, formerly called emanation, was discovered a few years after radium. /sup 222/Rn, the longest-lived isotope, has a half-life of 3,82 days. This half life is so short that the experimental techniques available at present (1978) are not sufficient for a characterization of defined radon compounds, even though there are definite indications for the existence of such compounds, and one may expect such radon compounds to be even more stable than the numerous known xenon compounds. - The radon isotopes /sup 219/Rn (Actinon), /sup 220/Rn (Thoron), and /sup 222/Rn (Radon) occur in nature despite their rather short half-lives, because they are continously generated from their mothers /sup 223/Ra, /sup 224/Ra, and /sup 226/Ra, which are in secular equilibrium with long-lived isotopes /sup 235/U, /sup 238/U, and /sup 232/Th, and are in turn continously formed from these long-lived isotopes. Since the radon isotopes are gases, they enter the atmosphere and are carried for long distances with air currents. - Because radon is so short-lived, its practical applications are rather limited. For medical applications, small sealed glass tubes filled with radon are used as radiation sources after the radon has decayed, because the whole series of Po-, Bi-, and Pb-isotopes of the radium decay chain are formed, whose penetrating radiation is useful for therapy. When solids are spiked with Ra isotopes, radon is evolved at a constant rate. On heating such solids, phase transitions show up by sudden increased radon evolution (Hahn's emanation method). - On the basis of nuclear theoretical calculations, there is hardly a chance for the discovery of a long-lived radon species. Therefore, major progress in radon chemistry is hardly to be expected in the near future.

  10. Comparison of field-measured radon diffusion coefficients with laboratory-measured coefficients

    International Nuclear Information System (INIS)

    Lepel, E.A.; Silker, W.B.; Thomas, V.W.; Kalkwarf, D.R.

    1983-04-01

    Experiments were conducted to compare radon diffusion coefficients determined for 0.1-m depths of soils by a steady-state method in the laboratory and diffusion coefficients evaluated from radon fluxes through several-fold greater depths of the same soils covering uranium-mill tailings. The coefficients referred to diffusion in the total pore volume of the soils and are equivalent to values for the quantity, D/P, in the Generic Environmental Impact Statement on Uranium Milling prepared by the US Nuclear Regulatory Commission. Two soils were tested: a well-graded sand and an inorganic clay of low plasticity. For the flux evaluations, radon was collected by adsorption on charcoal following passive diffusion from the soil surface and also from air recirculating through an aluminum tent over the soil surface. An analysis of variance in the flux evaluations showed no significant difference between these two collection methods. Radon diffusion coefficients evaluated from field data were statistically indistinguishable, at the 95% confidence level, from those measured in the laboratory; however, the low precision of the field data prevented a sensitive validation of the laboratory measurements. From the field data, the coefficients were calculated to be 0.03 +- 0.03 cm 2 /s for the sand cover and 0.0036 +- 0.0004 cm 2 /s for the clay cover. The low precision in the coefficients evaluated from field data was attributed to high variation in radon flux with time and surface location at the field site

  11. Build up of radon, /sup 218/Po and /sup 214/Po in a Karlsruhe diffusion chamber as a function of time

    International Nuclear Information System (INIS)

    Fazal-ur-Rehman; Jamil, K.; Ali, S.; Khan, H.A.

    1996-01-01

    Passive radon /sup 222/Rn dosimeters employing particle detectors are widely used in concentration (p Ci/l) measurement in houses, mines and other areas of activity. These dosimeters yield track density which is needed to be converted into physically meaningful parameter of radon concentration in either p Ci/l or Bq m/sup -3/. Therefore, it is required to know the separate contributions of /sup 222/Rn and its progeny. In the present study we have measured the concentration of /sup 222/Rn and its daughters (/sup 218/Po and /sup 214/Po) separately in the Karlsruhe diffusion chamber radon dosimeter, with and without a filter, as a function of time by an active method using a surface barrier detector. The build up behavior of radon and its two daughters (/sup 218/Po and /sup 214/Po) as a function of time was studied by plotting the area under each peak versus collection time. The differential curves and the relative concentration of radon daughters as a function of time were also studied. The concentration of radon and its daughters shows a somewhat linear build up as a function of time for the presently studied time periods. The results of this experiment are expected to be useful in converting the integrated alpha track density as measured by a particle track detector, (used in passive radon dosimetry) to radon concentration levels and for determination of equilibrium factor. (author)

  12. A study of radon indoor concentration

    International Nuclear Information System (INIS)

    Pena, P.; Ruiz, W.; Segovia, N.; Ponciano, G.

    2000-01-01

    It was realized a study of radon concentration in houses of Mexico City and in a laboratory of the Nuclear Centre of Salazar, State of Mexico. The radon determination in air was realized with solid nuclear track detectors and with Honeywell and Alpha guard automatic equipment. The results show that the majority of houses have values under 148 Bq/m 3 obtaining some housings with upper values located in the Lomas zone. A study in smokers houses and another of controls showed very similar distributions. It was studied the day time fluctuations finding that radon increases considerably during the dawn. Some upper values obtained in a laboratory of the Nuclear Centre were remedied with ventilation. (Author)

  13. A study of radon variation in dwelling during 1988

    International Nuclear Information System (INIS)

    Shaikh, A.N.; Ramachandran, T.V.; Muraleedharan, T.S.; Subbaramu, M.C.

    1989-01-01

    Natural radioactivity due to radon and its progeny levels indoors contributes significantly to the total radiation to man. The main source of radon and its progeny in a dwelling is the emanation of radon gas from soil. The temperature and ventilation vary in a dwelling during the year. These parameters influence the indoor radon levels. The seasonal variation of radon was studied in a dwelling as well as in the outside air. The filter paper method and alpha counting, and the solid state track detector technique and track counting were used to study the radon levels. The geometric mean of radon daughters concentrations were 0.5 mWL and 0.8 mWL measured by filter-paper method and SSNTD method respectively. The geometric mean of radon concentrations were 6.2 Bqm -3 and 10.0 Bqm -3 by filter-paper method and SSNTD method respectively. (author). 3 figs., 3 tabs., 13 refs

  14. Radon anomalies prior to earthquakes (1). Review of previous studies

    International Nuclear Information System (INIS)

    Ishikawa, Tetsuo; Tokonami, Shinji; Yasuoka, Yumi; Shinogi, Masaki; Nagahama, Hiroyuki; Omori, Yasutaka; Kawada, Yusuke

    2008-01-01

    The relationship between radon anomalies and earthquakes has been studied for more than 30 years. However, most of the studies dealt with radon in soil gas or in groundwater. Before the 1995 Hyogoken-Nanbu earthquake, an anomalous increase of atmospheric radon was observed at Kobe Pharmaceutical University. The increase was well fitted with a mathematical model related to earthquake fault dynamics. This paper reports the significance of this observation, reviewing previous studies on radon anomaly before earthquakes. Groundwater/soil radon measurements for earthquake prediction began in 1970's in Japan as well as foreign countries. One of the most famous studies in Japan is groundwater radon anomaly before the 1978 Izu-Oshima-kinkai earthquake. We have recognized the significance of radon in earthquake prediction research, but recently its limitation was also pointed out. Some researchers are looking for a better indicator for precursors; simultaneous measurements of radon and other gases are new trials in recent studies. Contrary to soil/groundwater radon, we have not paid much attention to atmospheric radon before earthquakes. However, it might be possible to detect precursors in atmospheric radon before a large earthquake. In the next issues, we will discuss the details of the anomalous atmospheric radon data observed before the Hyogoken-Nanbu earthquake. (author)

  15. Studies of radon mitigation in well water by aeration

    International Nuclear Information System (INIS)

    Mafra, Karina Cristina; Paschuk, Sergei A.; Denyak, Valeriy; Reque, Marilson; Correa, Janine Nicolosi; Barbosa, Laercio

    2011-01-01

    The 222 Rn concentration in natural water in different countries usually is about few Bq/L and is the subject of the National legislation as well as International norms and recommendations. The United States Environmental Protection Agency (USEPA) established a limit of 11.1 Bq/L for the radon level in drinking water and this limit is considered as guideline in Canada and many countries of the European Union. This work presents the results of study of radon ( 222 Rn) concentration reduction in well water using the aeration process developed at the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR). The water samples were collected from a well at Pinheirinho region of Curitiba in 2011. Experimental setup was based on the Radon Monitor (AlphaGUARD). The 222 Rn concentration was analyzed using the software DataEXPERT by Genitron Instruments, taking into account the volume of water sample, its temperature, atmospheric pressure and the total volume of the air in the vessels. Initial concentration of radon in water samples was 28,67 Bq/L which is bigger than maximum concentration recommended by USEPA. The mitigation was performed by means of diffusion aeration of water samples of 15L during the time interval of 24 hours following a period of 4 days. The efficiency of aeration mitigation was controlled by comparing the activity of radon in aerated water with reference water samples that were not aerated. Obtained results show very satisfactory decrease of 222 Rn activity in water samples even after few hours of intense aeration. (author)

  16. Determination of the diffusion coefficient and solubility of radon in plastics.

    Science.gov (United States)

    Pressyanov, D; Georgiev, S; Dimitrova, I; Mitev, K; Boshkova, T

    2011-05-01

    This paper describes a method for determination of the diffusion coefficient and the solubility of radon in plastics. The method is based on the absorption and desorption of radon in plastics. Firstly, plastic specimens are exposed for controlled time to referent (222)Rn concentrations. After exposure, the activity of the specimens is followed by HPGe gamma spectrometry. Using the mathematical algorithm described in this report and the decrease of activity as a function of time, the diffusion coefficient can be determined. In addition, if the referent (222)Rn concentration during the exposure is known, the solubility of radon can be determined. The algorithm has been experimentally applied for different plastics. The results show that this approach allows the specified quantities to be determined with a rather high accuracy-depending on the quality of the counting equipment, it can be better than 10 %.

  17. Indoor Radon Concentration Related to Different Radon Areas and Indoor Radon Prediction

    Science.gov (United States)

    Juhásová Šenitková, Ingrid; Šál, Jiří

    2017-12-01

    Indoor radon has been observed in the buildings at areas with different radon risk potential. Preventive measures are based on control of main potential radon sources (soil gas, building material and supplied water) to avoid building of new houses above recommended indoor radon level 200 Bq/m3. Radon risk (index) estimation of individual building site bedrock in case of new house siting and building protection according technical building code are obligatory. Remedial actions in buildings built at high radon risk areas were carried out principally by unforced ventilation and anti-radon insulation. Significant differences were found in the level of radon concentration between rooms where radon reduction techniques were designed and those where it was not designed. The mathematical model based on radon exhalation from soil has been developed to describe the physical processes determining indoor radon concentration. The model is focused on combined radon diffusion through the slab and advection through the gap from sub-slab soil. In this model, radon emanated from building materials is considered not having a significant contribution to indoor radon concentration. Dimensional analysis and Gauss-Newton nonlinear least squares parametric regression were used to simplify the problem, identify essential input variables and find parameter values. The presented verification case study is introduced for real buildings with respect to various underground construction types. Presented paper gives picture of possible mathematical approach to indoor radon concentration prediction.

  18. Measurements on, and modelling of diffusive and advective radon transport in soil

    DEFF Research Database (Denmark)

    Graff, E.R. van der; Witteman, G.A.A.; Spoel, W.H. van der

    1994-01-01

    Results are presented of measurements on radon transport in soil under controlled conditions with a laboratory facility consisting of a stainless steel vessel (height and diameter 2 m) filled with a uniform column of sand. At several depths under the sand surface, probes are radially inserted...... into the vessel to measure the radon concentration in the soil gas. To study advective radon transport a perforated circular box is placed in the sand close to the bottom of the vessel. By pressurising this box, an air flow through the sand column is induced. Radon concentration profiles were measured without...... an air flow as a function of time, and for several values of the air flow, equilibrium radon concentration profiles were measured....

  19. Low-cost Radon Reduction Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Rose, William B. [Univ. of Illinois, Urbana-Champaign, IL (United States); Francisco, Paul W. [Univ. of Illinois, Urbana-Champaign, IL (United States); Merrin, Zachary [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2015-09-01

    The U.S. Department of Energy's Building America research team Partnership for Advanced Residential Retrofits conducted a primary scoping study on the impact of air sealing between the foundation and the living space on radon transport reduction across the foundation and living space floor assembly. Fifteen homes in the Champaign, Illinois, area participated in the study. These homes were instrumented for hourly continuous radon measurements and simultaneous temperature and humidity measurements. Blower door and zone pressure diagnostics were conducted at each house. The treatments consisted of using air-sealing foams at the underside of the floor that separated the living space from the foundation and providing duct sealing on the ductwork that is situated in the foundation area. The hypothesis was that air sealing the floor system that separated the foundation from the living space should better isolate the living space from the foundation; this isolation should lead to less radon entering the living space from the foundation. If the hypothesis had been proven, retrofit energy-efficiency programs may have chosen to adopt these isolation methods for enhanced radon protection to the living space.

  20. Some characteristics of the AEOI [Atomic Energy Organisation of Iran] passive radon diffusion dosimeter

    International Nuclear Information System (INIS)

    Sohrabi, M.; Solaymanian, A.R.

    1988-01-01

    A passive radon diffusion dosimeter was developed for large-scale radon level measurements in Iran. It consists of a plastic cup with a polycarbonate alpha detector in the middle, a plastic tip cover with an opening holding a fiberglass filter and a hard aluminium mesh for protection and support. A new design for our multi-chamber electro-chemical etching (ECE) system was used for multiple foil etching. The effects of pre-etching and ECE times, chamber volume, filter diameter and foil position inside the chamber were investigated. The optimized geometries included 9.5 cm height, 296 cm 3 volume and 2-3 cm filter diameter with the PC foil mounted in the middle. A sensitivity of 0.05±0.007 tracks.cm -2 /Bq.m -3 .day or 1.86±0.28 tracks.cm -2 /pCi.1 -1 .day was obtained at optimized conditions. In this paper, the design and the characteristics of the dosimeter as well as some results of the optimization studies are reported and discussed. (author)

  1. Development of diffusion-based radon daughter dosimeters

    International Nuclear Information System (INIS)

    Phillips, C.R.; Khan, A.; Leung, H.

    1983-07-01

    The objective of this work is to investigate the possible application of the mechanisms of thermophoresis and electrostatic collection via electrets to the collection of radon daughters with reference to personal alpha dosimeters for use in uranium mines. The potential advantage accruing from adoption of either one of these collection mechanisms is that collection is passive and does not depend upon the use of a pump (active), and is, therefore, intrinsically much more reliable

  2. Study of the radon released from open drill holes

    International Nuclear Information System (INIS)

    Pacer, J.C.

    1981-06-01

    The radon emanating from three open drill holes was measured at a site of known uranium mineralization in the Red Desert of south central Wyoming. The radon flux from the soil and drill holes was measured by the accumulator method with activated charcoal cartridges. The surface soil was found to release radon at an average rate of 0.41 atoms/cm 2 /sec; the radon emanating from the holes was more variable than that from the soil. The three holes studied released an average of 47 atoms/cm 2 /sec of radon. This average is equivalent to the radon released to the atmosphere by 14.5 ft 2 of soil. The data indicate that the radon emanated from an open drill hole is not as significant as other possible activities at a drill site (i.e. digging a trench or drilling a hole) or from household activities involving the usage of water

  3. Radon

    International Nuclear Information System (INIS)

    Holmen, R.W.

    1987-01-01

    The discovery that radon enters into residential and commercial structures and produces adverse health consequences to occupants thereof has raised issues for the real estate profession in connection with transactions involving affected structures. The legal responsibilities of real estate professionals in relation to such structures have not yet been clearly defined. Moreover, consistent and reliable testing methods and results, clear identification of circumstances where testing is necessary, and consensus as to health risks suggested by various radon levels have yet to be achieved. When these legal and technical questions are clarified, real estate buyer and sellers as well as agents and brokers will be greatly benefited

  4. Indoor radon level measurements in Iran using AEOI passive dosimeters

    International Nuclear Information System (INIS)

    Sohrabi, M.; Solaymanian, A.R.

    1988-01-01

    A passive radon diffusion dosimeter was developed at the RPD of AEOI for nationwide indoor radon level measurements. Several parameters of the dosimeter were studied. Radon levels were determined in about 250 houses in Ramsar (a high natural radiation area), Tehran, Babolsar and Gonabad. In this paper, the results of some dosimeter parameters as well as radon levels in indoor air are reported

  5. Radon removal equipment based on aeration: A literature study of tests performed in Sweden between 1981 and 1996

    International Nuclear Information System (INIS)

    Mjoenes, L.

    2000-02-01

    In Sweden some principles to reduce the radon concentration in drinking water were tested in the beginning of the 1980s. Spray aeration under atmospheric pressure, diffused bubble aeration, aeration in the pressure tank and different combinations of these principles were studied. Aeration in the drill hole and adsorption on granulated activated char-coal were also tested. The best results, about 70 % reduction, were obtained with aeration in the pressure tank with a spray system combined with diffused air bubbling. The Oerebro project in the beginning of the 1990s included on site testing of five different aeration solutions: Aeration in the drill hole, aeration in the storage tank, ejector aeration, shallow tray aeration and packed column aeration. The radon removal efficiency varied between 20 % and 99 %. In 1994 a study intended to test the radon removal capacity of different water treatment equipment was performed. Six units of radon separators were included but most of the tested equipment was installed for other water treatment purposes. The performed measurements showed that the only types of equipment that reduce the radon concentration efficiently are radon separators and reverse osmosis filters. The radon removal capacity of the radon separators varied between 23 % and 97 %. In 1996 the nine most common radon separators on the Swedish market were tested. The results showed that the tested radon removal equipment worked well, although the technical quality and chosen technical solutions were not always the best. The radon removal capacity of the units participating in this test was in most cases between 96 and 99 %. In some cases the capacity exceeded 99 %. In order to reach this radon removal capacity the water must be recirculated in a storage tank under atmospheric pressure

  6. Radon removal equipment based on aeration: A literature study of tests performed in Sweden between 1981 and 1996

    Energy Technology Data Exchange (ETDEWEB)

    Mjoenes, L

    2000-02-01

    In Sweden some principles to reduce the radon concentration in drinking water were tested in the beginning of the 1980s. Spray aeration under atmospheric pressure, diffused bubble aeration, aeration in the pressure tank and different combinations of these principles were studied. Aeration in the drill hole and adsorption on granulated activated char-coal were also tested. The best results, about 70 % reduction, were obtained with aeration in the pressure tank with a spray system combined with diffused air bubbling. The Oerebro project in the beginning of the 1990s included on site testing of five different aeration solutions: Aeration in the drill hole, aeration in the storage tank, ejector aeration, shallow tray aeration and packed column aeration. The radon removal efficiency varied between 20 % and 99 %. In 1994 a study intended to test the radon removal capacity of different water treatment equipment was performed. Six units of radon separators were included but most of the tested equipment was installed for other water treatment purposes. The performed measurements showed that the only types of equipment that reduce the radon concentration efficiently are radon separators and reverse osmosis filters. The radon removal capacity of the radon separators varied between 23 % and 97 %. In 1996 the nine most common radon separators on the Swedish market were tested. The results showed that the tested radon removal equipment worked well, although the technical quality and chosen technical solutions were not always the best. The radon removal capacity of the units participating in this test was in most cases between 96 and 99 %. In some cases the capacity exceeded 99 %. In order to reach this radon removal capacity the water must be recirculated in a storage tank under atmospheric pressure.

  7. Comparative study on radon effects and thermal effects on humans in radon hot spring therapy

    International Nuclear Information System (INIS)

    Yamaoka, K.; Mitsunobu, F.; Hanamoto, K.; Tanizaki, Y.; Sugita, K.; Kohima, S.

    2003-01-01

    Full text: The radon therapy is used radon ( 222 Rn) gas, which mainly emits alpha-rays, and induces a small amount of active oxygen in the body. Because most of the diseases to which the radon therapy as well as the thermal therapy is applied are related to activated oxygen, in this study the effects of the radioactivity of radon and thermal effects were compared under the room or the hot spring condition with the similar chemical component, using as the parameters which are closely involved in the clinical for radon therapy. In the results, the radon and thermal therapy enhanced the antioxidation function, such as the activities of superoxide dismutase (SOD) and catalase, which inhibit lipid peroxidation and total cholesterol produce in the body. Moreover the therapy enhanced concanavalin A (ConA)-induced mitogen response, and increased the level of CD4, which is the marker of helper T cell, and decreased the level of CD8, which is the common marker of killer T cell and supresser T cell, in the white cell differentiation antigen (CD4/CD8) assay. Furthermore, the therapy increased the levels of alpha atrial natriuretic polypeptide (alpha ANP), beta endorphin, adrenocorticotropic hormone (ACTH), insulin and glucose-phosphate dehydrogenase (G-6-PDH), and decreased the vasopression level. The results were on the whole larger in the radon group than in the thermal group. The findings suggest that the radon therapy more contributes to the prevention of life style-related diseases related to peroxidation reactions and immune depression than thermal therapy. Moreover these indicate what may be a part of the mechanism for the alleviation of hypertension, osteoarthritis (pain) and diabetes mellitus brought about more radon therapy than thermal therapy

  8. Occupational exposure to radon in Australian Tourist Caves an Australian-wide study of radon levels

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, S B; Langroo, R; Peggie, J R [Australian Radiation Laboratory. Yallambie, VIC (Australia); Lyons, R G [University of Auckland, Auckland, (New Zealand). Department of Physics; James, J M [University of Sydney, Sydney, NSW (Australia). Department of Chemisty

    1996-02-01

    The study described in this report sets out to determine which Australian show caves have long- term radon levels in excess of the proposed action level of 1000 Bq m{sup -3}. The collaborative study between the Australian Radiation Laboratory (ARL), the University of Sydney and the University of Auckland, was carried out with the support of a Research Grant from Worksafe Australia. The aims of this study were to measure radon levels for each season over a period of one year, at representative sites in all developed show caves around Australia, to determine yearly average radon levels for each cave tour, based on these site measurements, to estimate the radiation doses to the tour guides employed in these caves, and to identify caves with radon concentrations in excess of the action level. (authors) 7 refs., 10 tabs., 2 figs.

  9. Occupational exposure to radon in Australian Tourist Caves an Australian-wide study of radon levels

    International Nuclear Information System (INIS)

    Solomon, S.B.; Langroo, R.; Peggie, J.R.; Lyons, R.G.; James, J.M.

    1996-02-01

    The study described in this report sets out to determine which Australian show caves have long- term radon levels in excess of the proposed action level of 1000 Bq m -3 . The collaborative study between the Australian Radiation Laboratory (ARL), the University of Sydney and the University of Auckland, was carried out with the support of a Research Grant from Worksafe Australia. The aims of this study were to measure radon levels for each season over a period of one year, at representative sites in all developed show caves around Australia, to determine yearly average radon levels for each cave tour, based on these site measurements, to estimate the radiation doses to the tour guides employed in these caves, and to identify caves with radon concentrations in excess of the action level. (authors)

  10. A study on the risk from indoor radon 220 and radon 222 exposures

    International Nuclear Information System (INIS)

    Rannou, A.

    1986-12-01

    The hazards from radon (radon 220 and 222) in dwelling atmospheres have been studied. In the first part devoted to the present state of the problem, an analysis is made of the formation mechanisms and the evolution of radon and its daughters indoors. The main physical and dosimetric quantities required for the risk evaluation are defined. The theoretical and experimental analysis of the methods of measurements of radon and its daughters used in the measurement campaign are considered in the second part. The progress and the result of the national survey are developed in the third part. The effects of several factors on indoor levels are discussed. The conclusions of a particular study in the Finistere ''department'' are presented. The data collected make it possible to assess the mean exposure of man to natural radiation [fr

  11. A new method for studying the transport of radon and thoron in various building materials using CR-39 and LR-115 solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Misdaq, M.A.; Ktata, A.; Bakhchi, A.

    2000-01-01

    Radon ( 222 Rn) and thoron ( 220 Rn) α-activities per unit volume were measured inside and outside different building materials by using two types of solid state nuclear track detectors (SSNTD) (CR-39 and LR-115 type II). In addition, the radon and thoron emanation coefficients of the studied materials were evaluated. Based on these data, the transport of radon and thoron across parallelepipedic blocks of the building materials could be investigated and radon and thoron global α-activities per unit volume outside different building material blocks were determined. Moreover, the diffusion length and the effective diffusion coefficient of radon in the building materials were evaluated and the total alpha activity due to radon in the atmospheres of different rooms consisting of different building materials was studied

  12. Study of the effects of radon in three biological systems

    International Nuclear Information System (INIS)

    Tavera, L.; Balcazar, M.; Lopez, A.; Brena, M.; Rosa, M.E. De la; Villalobos P, R.

    2002-01-01

    The radon and its decay products are responsible of the 3/4 parts of the exposure of the persons to the environmental radiation. The discovery at the end of XIX Century of the illnesses, mainly of cancer, which appeared in the presence of radon, lead to an accelerated growing of the radon studies: monitoring, dosimetry, effects on the persons, etc. Several epidemiological studies of radon in miners and population in general have been realized; advancing in the knowledge about the concentration-lung cancer risk relationship, but with discrepancies in the results depending on the concentration levels. Therefor, studies which consuming time, efforts and money go on doing. The research of the radon effects in biological systems different to human, allows to realize studies in less time, in controlled conditions and generally at lower cost, generating information about the alpha radiation effects in the cellular field. Therefor it was decided to study the response of three biological systems exposed to radon: an unicellular bacteria Escherichia Coli which was exposed directly to alpha particles from an electrodeposited source for determining the sensitivity limit of the chose technique. A plant, Tradescantia, for studying the cytogenetic effect of the system exposed to controlled concentrations of radon. An insect, Drosophila Melanogaster, for studying the genetic effects and the accumulated effects in several generations exposed to radon. In this work the experimental settlements are presented for the expositions of the systems and the biological results commenting the importance of these. (Author)

  13. Radon-222 measurements aboard an airplane for the description of atmospheric diffusion

    International Nuclear Information System (INIS)

    Bogen, J.

    1973-01-01

    Radon-222 is absorbed aboard an airplane in tubes filled with 50 g of selected charcoal and cooked in Dewars by carbon dioxide and freon. After air collection at different heights up to 5 km, the tubes are evacuated and heated in the laboratory for desorption of the gas molecules and for transfer into a decay chamber covered with zinc-sulfide serving as a scintillator for the detection of alpha activity from radon-222 and its daughters. In general, the measurements show an exponential decrease of the concentration up to 5 km in height, if there is no cloud layer. The height for a reduction by a factor of two is about 900 meters. Assuming a constant diffusion coefficient K 0 up to 5 km, the measurements yield a K 0 of approximately 3.7 x 10 4 cm 2 s -1 . For flights in stratiform clouds a decrease is observed of the concentration up to a certain height, then radon-222 is again increasing or remains constant. This must be explained with respect to the meteorological situation. Assuming only a constant value for K 0 between the different flying heights, it was possible to appraise the development of the eddy diffusion coefficient with height

  14. Comparative study of radon exposure in Canadian homes and uranium mines - a discussion on the importance of national radon program

    International Nuclear Information System (INIS)

    Chen, Jing

    2017-01-01

    The history of lung cancer in uranium miners is well known for over hundreds of years when the disease was referred to as 'miner's disease' or 'mountain sickness'. Radon levels in uranium mines have decreased significantly over the past 30 years as a result of effective radiation protection measures at workplaces. For the most recent 10-year period, the average radon concentrations to underground and surface workers in Canadian uranium mines were 111 and 11 Bq m -3 , respectively. Based on the recent radon survey carried out in roughly 14 000 homes in 121 health regions across Canada and the more recent radon and thoron survey in 33 Canadian cities and 4000 homes, the average radon concentration in Canadian homes is 77 Bq m -3 . This study demonstrates that, nowadays, workers are exposed to radon in underground mines at a comparable radon level to what Canadians are exposed to at home. Since exposure to indoor radon is the main source of natural radiation exposure to the population, it is important for the National Radon Program to further increase radon awareness, and to encourage more Canadians to take appropriate actions to reduce radon exposure. (authors)

  15. Study and treatment of situations implying radon

    International Nuclear Information System (INIS)

    Robe, M.Ch.

    2005-01-01

    The radon is a radioactive gas with a natural origin. It comes from a disintegration of uranium and radium present in the soils. It comes from granitic and volcanic subsoils. The radon can accumulate in buildings. It is the principal source of natural exposure and the second one after medical exposures. It is the only one source of radiations on which man is susceptible to act. Ventilation and airtightness are solutions to reduce radon concentration. (N.C.)

  16. The use of track registration detectors to reconstruct contemporary and historical airborne radon ( sup 2 sup 2 sup 2 Rn) and radon progeny concentrations for a radon-lung cancer epidemiologic study

    CERN Document Server

    Steck, D J

    1999-01-01

    Epidemiologic studies that investigate the relationship between radon and lung cancer require accurate estimates for the long-term average concentrations of radon progeny in dwellings. Year-to-year and home-to-home variations of radon in domestic environments pose serious difficulties for reconstructing an individual's long-term radon-related exposure. The use of contemporary radon gas concentrations as a surrogate for radon-related dose introduces additional uncertainty in dose assessment. Studies of glass exposed in radon chambers and in a home show that radon progeny deposited on, and implanted in, glass hold promise for reconstructing past radon concentrations in a variety of atmospheres. We developed an inexpensive track registration detector for the Iowa Radon Lung Cancer Study (IRLCS) that simultaneously measures contemporary airborne radon concentrations, surface deposited alpha activity density, and implanted sup 2 sup 1 sup 0 Po activity density. The implanted activity is used to reconstruct the cum...

  17. Study on the influence factors about the soil radon measurement

    International Nuclear Information System (INIS)

    Wu Zixiang; Liu Yanbin; Jia Yuxin; Mai Weiji; Liu Xiaolian; Yang Yuhua

    2006-01-01

    Objective: To explore relevant factors about the soil radon measurement and provide gist of formulating correct measure method by studying the way of the soil radon measurement. Methods: Deflation-ionization room standard is adopted. Results: The concentration of soil radon becomes higher with the sample's volume added, it also augmented with the measure depth increased in certain degree; The concentration of soil radon changes little when sample's depth is above 60 cm; The time of deflation has no obvious influence on the concentration of soil radon, but microwave show serious effect on it; The results will be lowered when the desiccant is humidified, raining has the same affection on it; Plant has some impact on it. Conclusion: The measured results will be affected by microwave, oscillate and plant. Sample's volume and depth, soil's humidity can influence it too. The result's veracity can be guaranteed by choosing appropriate sample and measure condition. (authors)

  18. Analysis of soil radon data in earthquake precursory studies

    Directory of Open Access Journals (Sweden)

    Hari Prasad Jaishi

    2014-10-01

    Full Text Available Soil radon data were recorded at two selected sites along Mat fault in Mizoram (India, which lies in the highest seismic zone in India. The study was carried out during July 2011 to May 2013 using LR-115 Type II films. Precursory changes in radon concentration were observed prior to some earthquakes that occurred around the measuring sites. Positive correlation was found between the measured radon data and the seismic activity in the region. Statistical analysis of the radon data together with the meteorological parameters was done using Multiple Regression Method. Results obtained show that the method employed was useful for removing the effect of meteorological parameters and to identify radon maxima possibly caused by seismic activity.

  19. A study of radon indoor concentration; Un estudio de concentracion de radon intramuros

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Ruiz, W.; Segovia, N.; Ponciano, G. [ININ, Gerencia de Ciencias Ambientales, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    It was realized a study of radon concentration in houses of Mexico City and in a laboratory of the Nuclear Centre of Salazar, State of Mexico. The radon determination in air was realized with solid nuclear track detectors and with Honeywell and Alpha guard automatic equipment. The results show that the majority of houses have values under 148 Bq/m{sup 3} obtaining some housings with upper values located in the Lomas zone. A study in smokers houses and another of controls showed very similar distributions. It was studied the day time fluctuations finding that radon increases considerably during the dawn. Some upper values obtained in a laboratory of the Nuclear Centre were remedied with ventilation. (Author)

  20. Detailed analysis of radon flux studies at Australian uranium projects

    International Nuclear Information System (INIS)

    Mudd, Gavin M.

    2005-01-01

    The release of radon gas and radon progeny from uranium projects is a major issue during operation as well as for the design of rehabilitation works. In Australia, there have been a number of premining radon flux studies as part of the environmental investigation and potential development of recent uranium projects. There is also an increasing amount of operational data on radon fluxes and loads from various aspects of projects, such as tailings, waste rock and mills. Thus there exists much useful measured data which can be used to assess the design radon flux and load targets for rehabilitation. The main projects for which radon data exists includes Ranger, Olympic Dam, Beverley, Honeymoon, Jabiluka, Yeelirrie, Lake Way, Koongarra, Moline, Coronation Hill, Rockhole, Nabarlek, Rum Jungle, Port Pirie and Ben Lomond. To date, much of this data has not been systematically evaluated. The need to compile and assess this data is twofold. Firstly, to assess the loads released from uranium production as an input into life-cycle analyses of the nuclear fuel cycle, such as those undertaken by UNSCEAR and industry groups. Secondly, there is a need to set suitable design standards for radon flux for the rehabilitation of former and current uranium projects. This paper will present such a detailed compilation of radon fluxes and loads which can then be used as the basis for both life-cycle analyses as well as setting appropriate site-specific rehabilitation criteria for radon. The implications for former and current projects is then discussed as well as future data needs. Ultimately, there is a critical need for thorough baseline surveys prior to mining to ensure accurate assessments of changes to radon fluxes and loads. The data and analysis presented is considered applicable to all uranium projects in Australia, as well as being a useful model for considering such issues internationally

  1. Diffusion of radon in candidate soils for covering uranium-mill tailings

    International Nuclear Information System (INIS)

    Kalkwarf, D.R.; Silker, W.B.

    1984-01-01

    Diffusion coefficients were measured for radon in 34 soils that had been identified by uranium mill personnel as candidate soils for covering their tailings piles in order to reduce radon emission. The coefficients referred to diffusion in the total pore space of the soils. They were measured by a steady-state method using soil columns compacted to greater than 80% of their Proctor maximum packing densities, but with moisture contents generally less than would be expected at a tailings site. Three published empirical equations relating diffusion coefficients to soil moisture and porosity were tested with these data. The best fit was obtained with the equation: D = 0.70 exp [-4(m-mP - +m 5 )] in which P is the dry porosity of the soil and m is its moisture saturation, e.e. the fraction of pore volume filled with water. This equation was used to extrapolate measured coefficients to values expected at soil-moisture contents representative of tailings sites in the western United States. Extrapolated values for silty sands and clayey sands ranged from 0.004 to 0.06 cm 2 /s where w, the weight ratio of water to dry soil, is expected to vary from 0.04 to 0.09. Values for inorganic silts and clays ranged from 0.001 to 0.02 cm 2 /s where w is expected to vary from 0.10 to 0.13

  2. Diffusion coefficients of radon in candidate soils for covering uranium mill tailings

    International Nuclear Information System (INIS)

    Kalkwarf, D.R.; Silker, W.B.

    1983-10-01

    Diffusion coefficients were measured for radon in 34 soils that had been identified by uranium mill personnel as candidate soils for covering their tailings piles in order to reduce radon emission. The coefficients referred to diffusion in the total pore space of the soils. They were measured by a steady-state method using soil columns compacted to greater than 80% of their Proctor maximum packing densities, but with moisture contents generally less than would be expected at a tailings site. Three published empirical equations relating diffusion coefficients to soil moisture and porosity were tested with these data. The best fir was obtained with the equation: D = 0.70 exp [-4(m-mP 2 +m 5 )] in which P is the dry porosity of the soil and m is its moisture saturation, i.e. the fraction of pore volume filled with water. This equation was used to extrapolate measured coefficients to values expected at soil-moisture contents representative of tailings sites in the western United States. Extrapolated values for silty sands and clayey sands range from 0.004 to 0.06 cm 2 /s where w, the weight ratio of water to dry soil, is expected to vary from 0.04 to 0.09. Values for inorganic silts and clays ranged from 0.001 to 0.02 cm 2 /s where w is expected to vary from 0.10 to 0.13. 8 references, 1 figure, 1 table

  3. Measurements of indoor radon and radon progeny in Mexico City

    International Nuclear Information System (INIS)

    Cheng, Y.S.; Rodriguez, G.P.

    1996-01-01

    Indoor radon has been a public concern associated with increased lung cancer risks. Radon decay products interact with indoor aerosols to form progeny with different size distributions, which may influence the lung dosimetry when the progeny are inhaled. Air pollution in Mexico City is a serious problems with high particulate concentrations, but there are few reports of indoor radon measurement. The purposes of this study were to measure the aerosol concentration, radon concentration, and radon activity size distribution in the living area of three houses in Mexico City. The radon concentration was monitored by a RGM-3 radon gas monitor (Eberline, Inc., Santa Fe, NM). A graded diffusion battery was used to determine the progeny concentration and activity size distribution. The concentration and size distribution of the indoor aerosols were monitored by a quartz, crystal microbalance cascade impactor. Our measurements showed high concentrations of indoor aerosols (20-180 gg m -3 ). However, the radon concentrations-were low ( -1 ), but showed a clear diurnal pattern with peak concentrations from 2-10 AM. The activity size distributions of radon progeny were trimodal, with peaks of 0.6 nm, 4-5 nm, and 100 rim. Most activities were associated with large particle sizes. Our results indicated that indoor radon concentration was not high, due in part to a relatively high air exchange with outdoor air. The high aerosol concentration may also play an important part in the activity size distribution of radon progeny

  4. A reconnaissance study of radon concentrations in Hamadan city, Iran

    Directory of Open Access Journals (Sweden)

    G. K. Gillmore

    2010-04-01

    Full Text Available This paper presents results of a reconnaissance study that used CR-39 alpha track-etch detectors to measure radon concentrations in dwellings in Hamadan, western Iran, significantly, built on permeable alluvial fan deposits. The indoor radon levels recorded varied from 4 (i.e. below the lower limit of detection for the method to 364 Bq/m3 with a mean value of 108 Bq/m3 which is 2.5 times the average global population-weighted indoor radon concentration – these data augment the very few published studies on indoor radon levels in Iran. The maximum radon concentration in Hamadan occurs during the winter period (January to March with lower concentrations during the autumn. The effective dose equivalent to the population in Hamadan is estimated from this study to be in the region of 2.7 mSv/y, which is above the guidelines for dose to a member of the public of 1 mSv/y suggested by the International Commission on Radiological Protection (ICRP in 1993. This study supports other work in a number of countries that indicates such permeable "surficial" deposits as being of intermediate to high radon potential. In western Iran, the presence of hammered clay floors, the widespread presence of excavated qanats, the textural properties of surficial deposits and human behaviour intended to cope with winds are likely to be important factors influencing radon concentrations in older buildings.

  5. Radon in Syrian houses

    International Nuclear Information System (INIS)

    Othman, I.; Hushari, M.; Raja, G.; Alsawaf, A.

    1996-01-01

    A nationwide investigation of radon levels in Syrian houses was carried out during the period 1991-1993. Passive radon diffusion dosemeters using polycarbonate detectors were distributed in houses all over Syria. Detectors were subjected to electrochemical etching to reveal latent tracks of alpha particles. The mean radon concentration in Syrian houses was found to be 45 Bq m -3 with some values several times higher. This investigation indicated that there were a few houses in Syria that require remedial action. Most houses that have high levels of radon were found in the southern area, especially in the Damascus governorate. The study also indicated that radon concentrations were higher in old houses built from mud with no tiling. (author)

  6. Review of high-sensitivity Radon studies

    Science.gov (United States)

    Wojcik, M.; Zuzel, G.; Simgen, H.

    2017-10-01

    A challenge in many present cutting-edge particle physics experiments is the stringent requirements in terms of radioactive background. In peculiar, the prevention of Radon, a radioactive noble gas, which occurs from ambient air and it is also released by emanation from the omnipresent progenitor Radium. In this paper we review various high-sensitivity Radon detection techniques and approaches, applied in the experiments looking for rare nuclear processes happening at low energies. They allow to identify, quantitatively measure and finally suppress the numerous sources of Radon in the detectors’ components and plants.

  7. A reconnaissance study of radon concentrations in Hamadan city, Iran

    OpenAIRE

    Gillmore, G.; Jabarivasal, N.

    2010-01-01

    This paper presents results of a reconnaissance study that used CR-39 alpha track-etch detectors to measure radon concentrations in dwellings in Hamadan, western Iran, significantly, built on permeable alluvial fan deposits. The indoor radon levels recorded varied from 4 (i.e. below the lower limit of detection for the method) to 364 Bq/m3 with a mean value of 108 Bq/m3 which is 2.5 times the average global population-weighted indoor radon concent...

  8. Occupational studies of radon daughters and lung cancer

    International Nuclear Information System (INIS)

    Hornung, R.W.; Ballew, M.A.

    1988-01-01

    The relationship between exposure to radon daughters and lung cancer mortality has been established. The purpose of this paper is to review some of the major studies of the health effects due to exposure to the decay products of radon gas and to discuss their potential implications with regard to risk associated with indoor radon. There has been much recent interest in the health hazards associated with radon largely motivated by the discovery of high levels of this radioactive gas in the Reading Prong (a geological area in Pennsylvania and New Jersey) and subsequently throughout the United States. Although at least three studies in the U.S. have been initiated to better estimate the lung cancer risks from low level indoor radon exposure, the results will not be known for several years. Consequently, present knowledge concerning such risks is almost entirely derived from studies of underground exposure to miners. Those studies effectively exclude women and children; therefore, assumptions must be made with regard to risk to a large segment of the population. Before discussing current health studies of radon daughter exposure, some background information is presented

  9. Radon and lung cancer: an epidemiological study in Norway

    International Nuclear Information System (INIS)

    Stranden, E.; Strand, T.; Magnus, K.; James, A.C.; Green, B.M.R.

    1988-01-01

    The objectives and strategy of an epidemiological study on the effects of exposure to radon in Norwegian dwellings is presented. The study is a cooperation between the National Institute of Radiation Hygiene and the Norwegian Cancer Registry in Norway and the National Radiological Protection Board of the United Kingdom, with funding by the Norwegian Cancer Society. Measurements of radon are being made in 10,000 dwellings representing all Norwegian municipalities. The potential for detecting an effect of radon exposure by such a study in Norway is unique because: (1) Radon concentrations are high and there are large regional variations. (2) Data from the Norwegian Cancer Registry is of high quality: all cancers have been subject to compulsory reporting since 1955. These data can be broken down according to municipality, sex and age. (3) In 1964/1965 a large scale survey of smoking habits was carried out in Norway. These data can also be broken down according to municipality, sex and age, and by types of smoking and smoking rate. It is intended to examine the correlation between lung cancer incidence and geographical variation in radon levels after making allowance for smoking habits. Radon measurements were started in early 1987 and the results of the study are expected to be published in 1989. (author)

  10. Study of the effects of radon in three biological systems; Estudio de los efectos del radon en tres sistemas biologicos

    Energy Technology Data Exchange (ETDEWEB)

    Tavera, L. [Instituto Mexicano del Petroleo, Av. Eje Central Lazaro Cardenas No. 152, Edif. 23, Col. San Mateo Atepehuacan, 07730 Mexico D.F. (Mexico); Balcazar, M.; Lopez, A.; Brena, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Rosa, M.E. De la [Facultad de Quimica, UNAM, 04510 Mexico D.F. (Mexico); Villalobos P, R. [Centro de Estudios de la Atmosfera, UNAM, 04510 Mexico D.F. (Mexico)

    2002-07-01

    The radon and its decay products are responsible of the 3/4 parts of the exposure of the persons to the environmental radiation. The discovery at the end of XIX Century of the illnesses, mainly of cancer, which appeared in the presence of radon, lead to an accelerated growing of the radon studies: monitoring, dosimetry, effects on the persons, etc. Several epidemiological studies of radon in miners and population in general have been realized; advancing in the knowledge about the concentration-lung cancer risk relationship, but with discrepancies in the results depending on the concentration levels. Therefor, studies which consuming time, efforts and money go on doing. The research of the radon effects in biological systems different to human, allows to realize studies in less time, in controlled conditions and generally at lower cost, generating information about the alpha radiation effects in the cellular field. Therefor it was decided to study the response of three biological systems exposed to radon: an unicellular bacteria Escherichia Coli which was exposed directly to alpha particles from an electrodeposited source for determining the sensitivity limit of the chose technique. A plant, Tradescantia, for studying the cytogenetic effect of the system exposed to controlled concentrations of radon. An insect, Drosophila Melanogaster, for studying the genetic effects and the accumulated effects in several generations exposed to radon. In this work the experimental settlements are presented for the expositions of the systems and the biological results commenting the importance of these. (Author)

  11. Transport studies of radon in limestone underlying houses

    International Nuclear Information System (INIS)

    Gammage, R.B.; Dudney, C.S.; Wilson, D.L.; Saultz, R.J.

    1990-01-01

    In hilly limestone terrains of the southern Appalachians, subterranean networks of solution cavities and fissures present circulatory systems facilitating convective and advective transport of radon-bearing gas. Evidence suggests that the primary driving forces for transport are aerostatic pressure differentials created by the difference between the underground and the outside air temperatures. Examples are presented of houses experiencing elevated indoor radon levels as a consequence of communicating with such subsurface transportation systems. The location of a house near the upper or lower end of a subterranean-circulatory system seems to produce amplification of indoor radon levels in winter or summer, respectively. The transport mechanism for radon-bearing air in karst and its impact on indoor radon need better understanding, both in regard to evaluating the geographical prevalence of the phenomenon and the induced spatial and temporal effects that are possible. This paper reports field studies made at houses in karst regions at Oak Ridge, Tennessee, and Huntsville, Alabama. A primary radon-transport mechanism is advocated of ascending or descending subsurface columns of air whose flows are largely driven by aerostatic pressure gradients created by the inground-outdoor air temperature differentials. 5 refs., 5 figs., 1 tab

  12. A study of radon levels in the soil of Nasir's College of Agriculture - Yemen

    International Nuclear Information System (INIS)

    Ali, Taher M.; Ahmed, Hayel A.; Zumalian, Abubaker A.

    2000-01-01

    The radon diffusion in the atmosphere and dwelling interior comes from one source, it is the soil. Emitting alpha particles, radon daughters may be deposited in to the lungs and cause health hazards, so for this reason, estimation of radon levels in soil and dwelling were done in may countries. in the present work, we have used the passive dosimeters (SSNTD s ) containing (Cr-39) detectors. The dosimeters were distributed at the surface of the ground, in the soil horizontally (at depth 50 cm) and in soil with depth. The overall mean for radon levels in soil horizontally was (1.28 ± 0.05) KBq/m 3 and the mean radon concentration at the surface of the ground was (0.42 ± 0.03) KBq/m 3 . It is found that radon concentration increases as the depth increases up to (90 cm) depth after that radon levels decrease as the depth increases. (author)

  13. Pilot study of the application of Tellus airborne radiometric and soil geochemical data for radon mapping

    Energy Technology Data Exchange (ETDEWEB)

    Appleton, J.D. [British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom)], E-mail: jda@bgs.ac.uk; Miles, J.C.H.; Green, B.M.R. [Health Protection Agency (HPA) - Radiation Protection Division, Chilton, Didcot, Oxon OX11 0RQ (United Kingdom); Larmour, R. [Environment and Heritage Service, Department of the Environment, Belfast BT7 2JA (United Kingdom)

    2008-10-15

    The scope for using Tellus Project airborne gamma-ray spectrometer and soil geochemical data to predict the probability of houses in Northern Ireland having high indoor radon concentrations is evaluated, in a pilot study in the southeast of the province, by comparing these data statistically with in-house radon measurements. There is generally good agreement between radon maps modelled from the airborne radiometric and soil geochemical data using multivariate linear regression analysis and conventional radon maps which depend solely on geological and indoor radon data. The radon maps based on the Tellus Project data identify some additional areas where the radon risk appears to be relatively high compared with the conventional radon maps. One of the ways of validating radon maps modelled on the Tellus Project data will be to carry out additional indoor measurements in these areas.

  14. Earthquake forecasting studies using radon time series data in Taiwan

    Science.gov (United States)

    Walia, Vivek; Kumar, Arvind; Fu, Ching-Chou; Lin, Shih-Jung; Chou, Kuang-Wu; Wen, Kuo-Liang; Chen, Cheng-Hong

    2017-04-01

    For few decades, growing number of studies have shown usefulness of data in the field of seismogeochemistry interpreted as geochemical precursory signals for impending earthquakes and radon is idendified to be as one of the most reliable geochemical precursor. Radon is recognized as short-term precursor and is being monitored in many countries. This study is aimed at developing an effective earthquake forecasting system by inspecting long term radon time series data. The data is obtained from a network of radon monitoring stations eastblished along different faults of Taiwan. The continuous time series radon data for earthquake studies have been recorded and some significant variations associated with strong earthquakes have been observed. The data is also examined to evaluate earthquake precursory signals against environmental factors. An automated real-time database operating system has been developed recently to improve the data processing for earthquake precursory studies. In addition, the study is aimed at the appraisal and filtrations of these environmental parameters, in order to create a real-time database that helps our earthquake precursory study. In recent years, automatic operating real-time database has been developed using R, an open source programming language, to carry out statistical computation on the data. To integrate our data with our working procedure, we use the popular and famous open source web application solution, AMP (Apache, MySQL, and PHP), creating a website that could effectively show and help us manage the real-time database.

  15. Radon in drinking water in Co. Wicklow. A pilot study

    International Nuclear Information System (INIS)

    Ryan, T.P.; Sequeira, S.; McKittrick, L.; Colgan, P.A.

    2003-02-01

    Attention has been focused on the issue of radon in drinking water by a European Commission recommendation proposing that surveys should be undertaken in Member States to determine the scale and nature of exposures caused by radon in domestic drinking water supplies. The Commission recommends 1000 Bq/l as the radon activity concentration in private drinking water supplies above which remedial action to reduce the concentration should be taken. The logic behind the proposed action level is that it would broadly correspond to the risk posed to an individual from exposure to radon in the home at the current Reference Level of 200 Bq/m3 in air. A pilot study to assess the distribution and concentrations of radon in private ground water supplies was recently completed in Co. Wicklow. County Wicklow was selected for the study primarily on the basis that the underlying geology is predominantly granite with elevated uranium content. Furthermore, there is an estimated 1200 to 5000 private ground water supplies in use in the county and high radon activity concentrations in air in a significant number of dwellings have previously been predicted. As part of the pilot study, a number of scientific issues were addressed in order to underpin the results obtained and these are also discussed in the report. Radon activity concentrations were measured in the private ground water supplies of 166 houses in Co. Wicklow. In all cases the ground water was the principal source of drinking water for the house occupants. Four supplies had activity concentrations in excess of the Recommended EC action level of 1000 Bq/l, fifteen had activity concentrations between 500 and 1000 Bq/l, 51 were between 100 and 500 Bq/l and 96 had activity concentrations below 100 Bq/l. The doses estimated for the ingestion of radon bearing water vary significantly with the quantity of drinking water consumed and the degree to which the water has been processed prior to consumption. However dose estimates based

  16. Radon in drinking water in Co. Wicklow. A pilot study

    International Nuclear Information System (INIS)

    Ryan, T.P.; Sequeira, S.; McKittrick, L.; Colgan, P.A.

    2003-01-01

    Attention has been focused on the issue of radon in drinking water by a European Commission recommendation proposing that surveys should be undertaken in Member States to determine the scale and nature of exposures caused by radon in domestic drinking water supplies. The Commission recommends 1000 Bq/l as the radon activity concentration in private drinking water supplies above which remedial action to reduce the concentration should be taken. The logic behind the proposed action level is that it would broadly correspond to the risk posed to an individual from exposure to radon in the home at the current Reference Level of 200 Bq/m 3 in air. A pilot study to assess the distribution and concentrations of radon in private ground water supplies was recently completed in Co. Wicklow. County Wicklow was selected for the study primarily on the basis that the underlying geology is predominantly granite with elevated uranium content. Furthermore, there is an estimated 1200 to 5000 private ground water supplies in use in the county and high radon activity concentrations in air in a significant number of dwellings have previously been predicted. As part of the pilot study, a number of scientific issues were addressed in order to underpin the results obtained and these are also discussed in the report. Radon activity concentrations were measured in the private ground water supplies of 166 houses in Co. Wicklow. In all cases the ground water was the principal source of drinking water for the house occupants. Four supplies had activity concentrations in excess of the Recommended EC action level of 1000 Bq/l, fifteen had activity concentrations between 500 and 1000 Bq/l, 51 were between 100 and 500 Bq/l and 96 had activity concentrations below 100 Bq/l. The doses estimated for the ingestion of radon bearing water varies significantly with the quantity of drinking water consumed and the degree to which the water has been processed prior to consumption. However dose estimates

  17. Determination of 222Rn levels in houses, schools and hotels of Ramsar by AEOI passive radon diffusion dosimeters

    International Nuclear Information System (INIS)

    Sohrabi, M.; Zainali, H.; Mahdi, Sh.; Solaymanian, A.R.; Salehi, M.

    1993-01-01

    Radon-222 levels were determined in 473 rooms of about 350 houses, 16 schools in Ramsar and its high-level natural radiation areas (HLNRAs) as well as in 89 rooms and many locations of old and new Ramsar Hotels. The AEOI (Atomic Energy Organization of Iran) Radon Diffusion Dosimeters applying electrochemical etching of polycarbonate detectors were used indoors during different seasons. The levels measured ranged from 20 to 3700 Bq.m -3 , detected in Talesh Mahalleh which has the highest natural radiation level in the area, corresponding to effective dose equivalents (H e ) up to 98.5 mSv.a -1 . The mean radon levels determined in different regions were 615 Bq.m -3 in Talesh Mahalleh, 326 Bq.m -3 in Chaparsar, 258 Bq.m -3 in schools of Ramsar and its HLNRAs, 246 Bq.m -3 in Ramak, 111 Bq.m -3 in Rasmar city, 50 Bq.m -3 in Sadat Mahalleh and Katalom, 49 Bq.m -3 Tonekabon and 27 Bq.m -3 in Talesh Mahalleh of Katalom; and 90 Be.m -3 in old and 50 Bq.m -3 in new Ramsar Hotels. It was found that houses built at a higher level above the ground even in the areas with the highest gamma exposures have lower radon levels compared to those built directly on the ground. The results of the radon levels determined in the above regions indoors are presented. (author). 10 refs, 9 figs, 3 tabs

  18. Characterizing the source of radon indoors

    International Nuclear Information System (INIS)

    Nero, A.V.; Nazaroff, W.W.

    1983-09-01

    Average indoor radon concentrations range over more than two orders of magnitude, largely because of variability in the rate at which radon enters from building materials, soil, and water supplies. Determining the indoor source magnitude requires knowledge of the generation of radon in source materials, its movement within materials by diffusion and convection, and the means of its entry into buildings. This paper reviews the state of understanding of indoor radon sources and transport. Our understanding of generation rates in and movement through building materials is relatively complete and indicates that, except for materials with unusually high radionuclide contents, these sources can account for observed indoor radon concentrations only at the low end of the range observed. Our understanding of how radon enters buildings from surrounding soil is poorer, however recent experimental and theoretical studies suggest that soil may be the predominant source in many cases where the indoor radon concentration is high. 73 references, 3 figures, 1 table

  19. Interaction of radon progeny with atmospheric aerosols

    International Nuclear Information System (INIS)

    Morawska, Lidia

    1994-01-01

    The radiological health hazard due to the airborne radon progeny depends on three factors (i) radon concentration in the air, (ii) radon progeny concentration, and (iii) active particle size distribution. Conclusions as to the health hazard cannot be drawn without full understanding of the interaction mechanisms between radon progeny and atmospheric aerosols. The aim of this work was to study the interaction mechanisms between radon progeny, natural environmental aerosols and environmental tobacco smoke (ETS). The experiments were performed under controlled laboratory conditions of radon concentration (1.85 and 3.70 Bq m -3 ), relative humidity (35, 50, 75 and 95%) and ETS generation. The size distribution of radioactivity carrying aerosols was measured using a wire screen diffusion battery system and size distribution of all airborne aerosols using a differential mobility particle sizer. The paper presents and discusses the results of activity size distribution and radon progeny concentration measurements for different environmental conditions. 7 refs., 2 tabs

  20. Radon exhalation study in cements and other building materials

    International Nuclear Information System (INIS)

    Singh, J.; Sharma, N.

    2012-01-01

    Radon is a radioactive inert gas, which is produced during the decay of radium, an element present in the naturally occurring uranium series. In the recent past, environmental scientists all over the world have been expressing great concern about the radiation hazard from radon and its short lived daughter products inside buildings. The radon concentration inside a building depends upon the radon exhalation from the building materials used for the construction and the soil underneath the building. In the present investigations, a comparative study for radon exhalation rate has been carried out in some Indian and Pakistani cements and other building materials being used locally such as sand, soil, bricks, marbles, CaCO 3 , POPs by using Track Etch Technique. The Pakistani cement with the trade name 'Elephant' shows the minimum mass exhalation rate while the Indian 'Birla White' cement has shown the maximum. Among the other building materials studied, CaCO 3 has shown the minimum, while local soil the maximum mass exhalation rate. Out of the fired clay bricks, roof tiles, floor tiles and different marbles, floor tiles have the minimum areal exhalation rate while roof tiles the maximum. (author)

  1. A study of indoor radon levels and radon effective dose in dwellings of some cities of Gezira State in Sudan

    Directory of Open Access Journals (Sweden)

    Elzain Abd-Elmoniem Ahmed

    2014-01-01

    Full Text Available Exposure to natural sources of radiation, especially 222Rn and its short-lived daughter products has become an important issue throughout the world because sustained exposure of humans to indoor radon may cause lung cancer. The indoor radon concentration level and radon effective dose rate were carried out in the dwellings of Medani, El Hosh, Elmanagil, Haj Abd Allah, and Wad Almahi cities, Gezira State - Central Sudan, in 393 measurements, using passive integrated solid-state nuclear track devices containing allyl diglycol carbonate plastic detectors. The radon concentration in the corresponding dwellings was found to vary from (57 ± 8 Bq/m3 in Medani to 41 ± 9 Bq/m3 in Wad Almahi, with an average of 49 ± 10 Bq/m3. Assuming an indoor occupancy factor of 0.8 and 0.4 for the equilibrium factor of radon indoors, we found that the annual effective dose rate from 222Rn in the studied dwellings ranges from 1.05 to 1.43 mSv per year and the relative lung cancer risk for radon exposure was 1.044%. In this research, we also correlated the relationship of radon concentration and building age. From our study, it is clear that the annual effective dose rate is larger than the “normal” background level as quoted by UNSCEAR, lower than the recommended action level of ICRP, and less than the maximum permissible dose defined by the International Atomic Energy Agency.

  2. Experimental study of ion-induced nucleation by radon decay

    International Nuclear Information System (INIS)

    He, F.; Hopke, P.K.

    1993-01-01

    In the environment, the presence of ions from natural radioactivity may increase the rate of new particle formation through ion-induced nucleation. A thermal diffusion cloud chamber (TDCC) has been built to experimentally study ion-induced nucleation where the ions are produced by gaseous radioactive sources. The critical supersaturation values and nucleation rates for methanol, ethanol, 1-propanol, and 1-butanol vapors on ions produced within the volume of the chamber by alpha decay of 222 Rn have been measured quantitatively at various radioactivity concentrations and supersaturations. The presence of ion tracks and the effect of an external electric field were also investigated. The alpha tracks and ion-induced nucleation formed by 222 Rn decay become visible at the critical supersaturation that is below the value needed for homogeneous nucleation. At this supersaturation, the nucleation rates increase substantially with increasing 222 Rn at low activity concentrations, but attain limiting values at higher concentrations. The experimental results indicate that the ionization by radon decay will promote ion-cluster formation and lower the free energy barriers. The formation of visible droplets is strongly dependent on the supersaturation. This study also confirms that the external electric field has a significant effect on the observed rates of nucleation

  3. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report describes studies on the chemical and physical behavior of the [sup 218]Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and its dose to the cells in the respiratory tract are to be fully assessed. The specific tasks of the controlled laboratory studies are to determine the formation rates of [center dot]OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO[sub 2] ethylene, and H[sub 2]S to lower vapor pressure compounds and determine the role of gas phase additives such as H[sub 2]O and NH[sub 3] in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of [sup 218]Po[sub x][sup +] in O[sub 2] at low radon concentrations. Tasks of the exposure studies in occupied indoor spaces are to initiate measurements of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants, to initiate a prospective study of the utility of measurement of deposited [sup 210]Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon, and to develop the methodology to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  4. Experimental animal studies of radon and cigarette smoke

    International Nuclear Information System (INIS)

    Cross, F.T.; Dagle, G.E.; Gies, R.A.; Smith, L.G.; Buschbom, R.L.

    1992-01-01

    Cigarette-smoking is a dominant cause of lung cancer and confounds risk assessment of exposure to radon decay products. Evidence in humans on the interaction between cigarette-smoking and exposure to radon decay products, although limited, indicates a possible synergy. Experimental animal data, in addition to showing synergy, also show a decrease or no change in risk with added cigarette-smoke exposures. This article reviews previous animal data developed at Compagnie Generale des Matieres Nucleaires and Pacific Northwest Laboratory (PNL) on mixed exposures to radon and cigarette smoke, and highlights new initiation-promotion-initiation (IPI) studies at PNL that were designed within the framework of a two-mutation carcinogenesis model. Also presented are the PNL exposure system, experimental protocols, dosimetry, and biological data observed to date in IPI animals

  5. Studies on deposition of radon daughters on glass surface

    International Nuclear Information System (INIS)

    Loerinc, M.; Feher, I.; Palfalvi, J.

    1998-01-01

    In a certain village in Northern Hungary, in some houses the radon concentration was found to be in the order of kBq.m -3 . In an attempt to decide whether an earthquake or the near-by mining activity is to blame, past radon concentration was studied making use of radon daughters embedded in the surface layer of glass sheets. In the investigation several conclusions were reached: drastic changes in Rn concentration could be excluded, ie., the high Rn concentration existed over the last 50 years; the continuing deposition of dirt on the glass surface and the occasional cleaning had no significant effect; the effect of corrosion processes at the glass surface should be further investigated. (A.K.)

  6. Review of epidemiological studies on hazards of radon daughters

    International Nuclear Information System (INIS)

    Myers, D.K.; Stewart, C.G.; Johnson, J.R.

    1981-01-01

    A review, with nearly 100 references, of the biological effects of radon and radon daughters is presented. Calculations of the relative dose from daughter products, as well as of the variation in dose with such things as unattached fraction, particle size, age and breathing rate are discussed. Estimates of annual risk of lung cancer in miners after inhalation of thoron daughters are given, and compared with hazards of employment in various US industries. The implications of these epidemiological studies for future regulations are discussed

  7. A detailed study of inexpensive radon control techniques in New York state houses

    International Nuclear Information System (INIS)

    Nitschke, I.A.; Wadach, J.B.; Clarke, W.A.; Traynor, G.W.; Adams, G.P.; Rizzuto, J.E.

    1984-01-01

    As part of a comprehensive indoor air quality and infiltration field study, radon concentrations were measured in 60 houses in upstate New York using passive integrating monitors. Indoor air radon concentrations ranged from 0.2 pCi/l to 50 pCi/l. Four houses with the highest radon levels were then extensively monitored using real-time continuous instruments for the measurement of radon, radon daughters, respirable particles, infiltration, inside-outside pressure difference, and weather parameters. Several inexpensive radon mitigation techniques were tested in these four houses. Their effectiveness ranged widely. Techniques identified as effective were permanently installed in 14 houses having indoor air radon concentration above 2 pCi/l. Finally, the long-term effectiveness of the installed control techniques is being tested using passive integrating radon monitors. (Author)

  8. Radon transport from uranium mill tailings via plant transpiration. Final report

    International Nuclear Information System (INIS)

    Lewis, B.A.G.

    1985-01-01

    Radon exhalation by vegetation planted on bare or soil-covered uranium mill wastes was studied based on an assumption that radon transport from soil to atmosphere via plants takes place in the transpiration stream. Results show that radon exhalation by plants is inversely related to water transpired, primarily a dilution effect. Radon released appeared directly related to leaf area, suggesting that radon is carried into the plant by mass flow in water; however, once within the plant, radon very likely diffuses through the entire leaf cuticle, while water vapor diffuses primarily through open stomates. Application of a computerized model for water transpiration to radon exhalation is not immediately useful until the role of water in radon transport is defined throughout the continuum from rooting medium to the atmosphere. Until then, a simple calculation based on leaf area index and Ra-226 concentration in the rooting medium can provide an estimate of radon release from revegetated wastes containing radium

  9. Modelling and experimental study of the behavior of radon and radon decay products in an enclosure. Application to houses

    International Nuclear Information System (INIS)

    Gouronnec, A.M.

    1995-01-01

    Since the eighties, more and more studies were performed about radon and its decay products in houses with one of the aim being the estimation of the dose received by their inhabitants. Then, the principal objective of this work is to describe the behaviour of radon and its decay products within a dwelling. In the first part to the report, a few definitions are given and data from literature give an idea of indoor radon and radon decay products activities and/or size distribution. Aspects of dosimetry are presented too. In the second part of the work, a mathematical model, called 'PRADDO' of Physic of Radon and radon Decay products in Domestic environment is developed on the basis of the classical model written by Jacobi in 1972. On the one hand, it has to predict radon decay products activities in systems consisting in one or more enclosure(s), from radon activity and from ambient aerosol concentration and size distribution. On the other hand, one part of the model is assigned to study the influence of the entry model parameters variation on the calculated quantities. Then, in the third part of the work, two experimental studies are realised in order to compare measurements to modelization. The first experimentation is a laboratory work, made on the test bench ICARE from IPSN, and the second one consists in describing the basement of an occupied house from Brittany. In the two cases, the comparison between experiments and modelling shows a good agreement if particles are present in the air, but any conclusion is made when is no aerosol in the enclosure. (author). 158 refs., 81 figs., 42 tabs

  10. Realization of a simulator for radon-222 underground migration studies

    International Nuclear Information System (INIS)

    Tidjani, A.; Seidel, J.L.; Monnin, M.; Isabelle, D.B.

    1987-01-01

    To study under controlled conditions the underground movements of radon gas a simulator has been built. It was designed in order to vary independently the different geophysical parameters such as pressure, temperature, humidity, type of soil and its granulometry, etc.. The first tests, described in this paper, have demonstrated the usefullness of such a simulator. (orig.)

  11. Progress in indoor radon measurement. Review of previous research (July 1981-February 1985)

    International Nuclear Information System (INIS)

    1985-01-01

    Research progress in the following areas is reported: (1) scintillation cell development and applications, (2) charcoal adsorption development and applications; (3) surveys with Terradex detectors; (4) radon carcinogenesis epidemiology; (5) large scale surveys of radon concentrations in randomly selected houses; (6) ventilation rate studies; (7) soil studies; (8) diffusion of radon through materials other than soil; and (9) test house studies

  12. ERRICCA radon model intercomparison exercise

    International Nuclear Information System (INIS)

    Andersen, C.E.; Albarracin, D.; Csige, I.; Graaf, E.R. van der; Jiranek, M.; Rehs, B.; Svoboda, Z.; Toro, L.

    1999-04-01

    Numerical models based on finite-difference or finite-element methods are used by various research groups in studies of radon-222 transport through soil and building materials. Applications range from design of radon remediation systems to more fundamental studies of radon transport. To ascertain that results obtained with these models are of good quality, it is necessary that such models are tested. This document reports on a benchmark test organized by the EU project ERRICCA: European Research into Radon in Construction Concerted Action. The test comprises the following cases: 1) Steady-state diffusive radon profiles in dry and wet soils, 2) steady-state entry of soil gas and radon into a house, 3) time-dependent radon exhalation from a building-material sample. These cases cover features such as: soil heterogeneity, anisotropy, 3D-effects, time dependency, combined advective and diffusive transport of radon, flux calculations, and partitioning of radon between air and water in soil pores. Seven groups participated in the intercomparison. All groups submitted results without knowing the results of others. For these results, relatively large group-to-group discrepancies were observed. Because of this, all groups scrutinized their computations (once more) and engaged in follow-up discussions with others. During this debugging process, problems were indeed identified (and eliminated). The accordingly revised results were in better agreement than those reported initially. Some discrepancies, however, still remain. All in all, it seems that the exercise has served its purpose and stimulated improvements relating to the quality of numerical modelling of radon transport. To maintain a high quality of modelling, it is recommended that additional exercises are carried out. (au)

  13. Studies of Radon and Radon Progeny in Air Conditioned Rooms in Hospitals

    International Nuclear Information System (INIS)

    Marley, F.; Denman, A.R.; Phillips, P.S.

    1998-01-01

    A series of continuous real-time radon and radon progeny measurements together with passive etched track detector measurements were performed in hospital premises during 1996. In one small room, detailed measurements over several weeks showed that both the radon concentration and the Equilibrium Factor depended on the intermittent operation of a filtered positive pressure displacement air-conditioning system, which was designed to conform to operating theatre standards. The average radon level measured while the air-conditioning was off was almost four times higher than that recorded whilst it was on. The progeny level was over five times higher than that whilst it was on. Thus, the Equilibrium Factor (F), was significantly lower when the air-conditioning was on. Measurements in similar rooms in two hospitals, confirmed that the reduction in radon level was a general finding. Thus staff working in such environments receive significantly lower radiation dose from radon than staff working in nearby normally ventilated rooms. (author)

  14. Studies on spatial distribution of indoor radon concentration at Mysore city, India

    International Nuclear Information System (INIS)

    Pruthvi Rani, K.S.; Chandrashekara, M.S.; Paramesh, L.

    2016-01-01

    Radon is a radioactive inert gas, with a half life of 3.82 days. Radium present in soil rocks and building material are the sources of atmospheric radon. Radon and its short-lived decay products ( 218 Po, 214 Pb, 214 Bi, and 214 Po) can be deposited in the lung tissues and give rise to higher radiation doses. Radon is now recognized as the second most important cause of lung cancer after smoking in the general population. In the present investigation a systematic study of the distribution of radon concentration has been carried out in a small room at different co-ordinates and time scales

  15. A study of radon levels in NHS premises in affected areas around the UK

    International Nuclear Information System (INIS)

    Denman, A.R.; Lewis, G.T.R.; Brennen, S.E.

    2002-01-01

    Radon gas contributes a significant fraction of the natural background radiation dose, and in some areas raised levels are found in buildings, both homes and the workplace. Different UK Action Levels apply to homes and the workplace, because of the diurnal variation of radon. This study reviews the results for a number of hospitals throughout England and Wales, and suggests that the likelihood of finding raised radon levels is similar in the workplace and homes in the same area. Radon measurements and consequent remediation of any raised levels are appropriate in all workplaces in radon Affected Areas with over 5% of houses above the UK domestic Action Level of 200 Bq m -3

  16. Human Lung Cancer Risks from Radon – Part III - Evidence of Influence of Combined Bystander and Adaptive Response Effects on Radon Case-Control Studies - A Microdose Analysis

    Science.gov (United States)

    Leonard, Bobby E.; Thompson, Richard E.; Beecher, Georgia C.

    2012-01-01

    Since the publication of the BEIR VI (1999) report on health risks from radon, a significant amount of new data has been published showing various mechanisms that may affect the ultimate assessment of radon as a carcinogen, in particular the potentially deleterious Bystander Effect (BE) and the potentially beneficial Adaptive Response radio-protection (AR). The case-control radon lung cancer risk data of the pooled 13 European countries radon study (Darby et al 2005, 2006) and the 8 North American pooled study (Krewski et al 2005, 2006) have been evaluated. The large variation in the odds ratios of lung cancer from radon risk is reconciled, based on the large variation in geological and ecological conditions and variation in the degree of adaptive response radio-protection against the bystander effect induced lung damage. The analysis clearly shows Bystander Effect radon lung cancer induction and Adaptive Response reduction in lung cancer in some geographical regions. It is estimated that for radon levels up to about 400 Bq m−3 there is about a 30% probability that no human lung cancer risk from radon will be experienced and a 20% probability that the risk is below the zero-radon, endogenic spontaneous or perhaps even genetically inheritable lung cancer risk rate. The BEIR VI (1999) and EPA (2003) estimates of human lung cancer deaths from radon are most likely significantly excessive. The assumption of linearity of risk, by the Linear No-Threshold Model, with increasing radon exposure is invalid. PMID:22942874

  17. Radon problems

    International Nuclear Information System (INIS)

    Cohen, B.L.

    1985-01-01

    This chapter examines the health hazards resulting from the release of naturally occurring radioactive gas derived from the decay of uranium. It is estimated that random inhalation is now causing about 10,000 fatal lung cancers per year in the US. Radon is constantly being generated in rocks and soils (in which uranium is naturally present) and in materials produced from them (e.g., brick, stone, cement, plaster). It is emphasized that radon levels in buildings are typically 5 times higher than outdoors because radon diffusing up from the ground below or out of bricks, stone, cement, or plaster is trapped inside for a relatively long time

  18. Study of the calibration of the medical physics department - radon dosimeter in a radon facility

    International Nuclear Information System (INIS)

    Nikololpoulos, D.; Louizi, A.; Papadimitriou, D.; Proukakis, C.

    1997-01-01

    Several techniques have been developed to measure radon indoors.The use of a Solid State Nuclear Track Detector closed in a cup, has turned out to be the most appropriate for long term measurements. The Medical Physics Department of the Athens University is carrying out radon measurements in dwellings, apartments, outdoor air and mines since 1996. For this purpose a simple device, the so called Medical Physics Department radon dosimeter, has been constructed, which measures the radon concentration averaged over a long period of time. In the present paper the calibration technique introduced and the results of the calibration of the Medical Physics Department. (authors)

  19. An electrical circuit model for simulation of indoor radon concentration.

    Science.gov (United States)

    Musavi Nasab, S M; Negarestani, A

    2013-01-01

    In this study, a new model based on electric circuit theory was introduced to simulate the behaviour of indoor radon concentration. In this model, a voltage source simulates radon generation in walls, conductivity simulates migration through walls and voltage across a capacitor simulates radon concentration in a room. This simulation considers migration of radon through walls by diffusion mechanism in one-dimensional geometry. Data reported in a typical Greek house were employed to examine the application of this technique of simulation to the behaviour of radon.

  20. Continuous measurements of soil radon under regular field conditions

    International Nuclear Information System (INIS)

    Font, LL

    1999-01-01

    Continuous soil radon measurements were performed in the frame of an European Community-radon network using the Clipperton II detector. It has been found that in some periods, soil radon levels obtained with one Clipperton II probe are very different from those obtained with another probe placed at the same depth but a short distance apart. It has been also found that the response of the probes to a sudden change of radon concentration is controlled by the diffusion process along the bottom tube of the probe. Therefore, this study shows that the experimental data can be attributed to the natural behaviour of soil radon

  1. An improved model for the reconstruction of past radon exposure.

    Science.gov (United States)

    Cauwels, P; Poffijn, A

    2000-05-01

    If the behavior of long-lived radon progeny was well understood, measurements of these could be used in epidemiological studies to estimate past radon exposure. Field measurements were done in a radon-prone area in the Ardennes (Belgium). The surface activity of several glass sheets was measured using detectors that were fixed on indoor glass surfaces. Simultaneously the indoor radon concentration was measured using diffusion chambers. By using Monte Carlo techniques, it could be proven that there is a discrepancy between this data set and the room model calculations, which are normally used to correlate surface activity and past radon exposure. To solve this, a modification of the model is proposed.

  2. Determination of equilibrium factor between radon and its progeny using surface barrier detector for various shapes of passive radon dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Jamil, K. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Fazal-ur-Rehman [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Ali, S. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group; Khan, H.A. [PINSTECH, Islamabad (Pakistan). Environ. Radiat. Group

    1997-03-21

    In the field of radon dosimetry, it is customary to measure radon ({sup 222}Rn) concentration while potential health hazard is due to the radon short-lived progeny. When radon is in secular equilibrium, the measured activity of radon equals the activity of radon`s progeny. However, in practical cases an inequilibrium between radon and its progeny exists which is measured in terms of the equilibrium factor. To determine the equilibrium factor between radon and its progeny in a closed environment various shapes of passive dosimeters based upon solid state nuclear track detectors (SSNTDs) are employed. In order to observe the dependence of equilibrium factor upon shapes or effective volumes, experiments have been performed replacing the SSNTDs with a surface barrier detector in Karlsruhe diffusion chamber, pen-type and box-type dosimeters. Using the collected alpha spectra, the equilibrium factor has been determined for a radon-air mixture in a custom designed radon chamber simulating a closed environment of a room. The results show that the radon equilibrium factor is about 0.20 for different shapes of dosimeters studied in this research. It is concluded that the determination of equilibrium factor between radon and its progeny does not depend upon effective volume or shape of the passive dosimeters using alpha spectroscopic data acquired by surface barrier detector. (orig.).

  3. The measurement of activity-weighted size distributions of radon progeny: methods and laboratory intercomparison studies

    International Nuclear Information System (INIS)

    Hopke, P.K.; Strydom, R.; Ramamurthi, M.; Knutson, E.O.; Tu, K.W.; Scofield, P.; Holub, R.F.; Cheng, Y.S.; Su, Y.F.; Winklmayr, W.

    1992-01-01

    Over the past 5 y, there have been significant improvements in measurement of activity-weighted size distributions of airborne radon decay products. The modification of screen diffusion batteries to incorporate multiple screens of differing mesh number, called graded screen arrays, have permitted improved size resolution below 10 nm such that the size distributions can now be determined down to molecular sized activities (0.5 nm). In order to ascertain the utility and reliability of such systems, several intercomparison tests have been performed in a 2.4 m3 radon chamber in which particles of varying size have been produced by introducing SO2 and H2O along with the radon to the chamber. In April 1988, intercomparison studies were performed between direct measurements of the activity-weighted size distributions as measured by graded screen arrays and an indirect measurement of the distribution obtained by measuring the number size distribution with a differential mobility analyzer and multiplying by the theoretical attachment rate. Good agreement was obtained in these measurements. A second set of intercomparison studies among a number of groups with graded screen array systems was made in April 1989 with the objective of resolving spectral structure below 10 nm. Again, generally good agreement among the various groups was obtained although some differences were noted. It is thus concluded that such systems can be constructed and can be useful in making routine measurements of activity-weighted size distributions with reasonable confidence in the results obtained

  4. Design issues in studies of radon and lung cancer: Implications of the joint effect of smoking and radon

    International Nuclear Information System (INIS)

    Upfal, M.; Divine, G.; Siemiatycki, J.

    1995-01-01

    Many case-control studies have been undertaken to assess whether and to what extent residential radon exposure is a risk factor for lung cancer. Nearly all these studies have been conducted in populations including smokers and nonsmokers. In this paper, we show that, depending on the nature of the joint effect of radon and tobacco on lung cancer risk, it may be very difficult to detect a main effect due to radon in mixed smoking and nonsmoking populations. If the joint effect is closer to additive than multiplicative, the most cost-effective way to achieve adequate statistical power may be to conduct a study among never-smokers. Because the underlying joint effect is unknown, and because many studies have been carried out among mixed smoker and nonsmoker populations, it would be desirable to conduct some studies with adequate power among never-smokers only. 30 refs., 4 figs., 2 tabs

  5. Relationship between indoor radon and lung cancer: a study of feasibility of an epidemiological study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, S.; Neuberg, D.; DuMouchel, W.; Kleitman, D.; Chernoff, H.

    1981-01-01

    This report describes a study to assess the feasibility of an epidemiologic investigation of the relationship between residential radon exposure and lung cancer. Field measurements of residential radon levels in the State of Maine are described. Using these radon measurements and BEIR, 1980 risk assessments, it is estimated that at most 10% of lung cancers in Maine can be considered attributable to residential radon exposure. Calculations are made of sample sizes necessary for a case-control study of radon and lung cancer, for several levels of radon and smoking health effects. The effects of misclassification of exposure variables on the probability of detecting a radon health effect are discussed. A comparison is made of three different mathematical models which could be used for sample size estimation. Dollar cost estimates are given for conducting an epidemiologic case-control study of the relationship between residential radon exposure and lung cancer.

  6. Relationship between indoor radon and lung cancer: a study of feasibility of an epidemiological study. Final report

    International Nuclear Information System (INIS)

    Rasmussen, S.; Neuberg, D.; DuMouchel, W.; Kleitman, D.; Chernoff, H.

    1981-01-01

    This report describes a study to assess the feasibility of an epidemiologic investigation of the relationship between residential radon exposure and lung cancer. Field measurements of residential radon levels in the State of Maine are described. Using these radon measurements and BEIR, 1980 risk assessments, it is estimated that at most 10% of lung cancers in Maine can be considered attributable to residential radon exposure. Calculations are made of sample sizes necessary for a case-control study of radon and lung cancer, for several levels of radon and smoking health effects. The effects of misclassification of exposure variables on the probability of detecting a radon health effect are discussed. A comparison is made of three different mathematical models which could be used for sample size estimation. Dollar cost estimates are given for conducting an epidemiologic case-control study of the relationship between residential radon exposure and lung cancer

  7. MODEL FOR UNSTEADY OF DIFFUSION –ADVECTION OF RADON IN SOIL – ATMOSPHERE

    Directory of Open Access Journals (Sweden)

    Parovik R.I.

    2010-04-01

    Full Text Available We consider a mathematical model for unsteady transport of radon from the constant coefficients in the soil – atmosphere. An explicit analytical solution for this model and built at different times of his profiles.

  8. Study of probes for geophysical process analysis. Radon-emanometry

    International Nuclear Information System (INIS)

    Tidjani, A.

    1984-09-01

    This study concerns mainly the measurement of radon-222 concentration in the ground, as an indicator of underground gas displacements. With nuclear track solid state detectors (SSNTD), it has been shown that the use of a radon source, buried at 180 cm depth, provides an increase of sensitivity. In order to automatize the in-field measurements, electronic detectors (scintillators, semi-conductors) have been developed. These detectors have been used for preliminary studies in the field for further applications to the prevision of earthquakes and volcanic eruption, and on a simulation set-up to analyse the possible influence of atmospheric parameters (pressure, temperature, ...) on underground gas displacement. Some tests have been done on the use of SSNTD for tracer analysis [fr

  9. Indoor radon

    International Nuclear Information System (INIS)

    1997-12-01

    The radon, a natural radioactive gas, is present almost everywhere on the earth's surface. It can be accumulated at high concentration in confined spaces (buildings, mines, etc). In the last decades many studies conducted in several countries showed that inhaling important amounts of radon rises the risk of lung cancer. Although, the radon is a naturally appearing radioactive source, it may be the subject of a human 'enhancement' of concentration. The increasing radon concentration in professional housing constitutes an example of enhanced natural radioactivity which can induce health risks on workers and public. Besides, the radon is present in the dwelling houses (the domestic radon). On 13 May 1996, the European Union Council issued the new EURATOM Instruction that establishes the basic standards of health protection of population and workers against the ionizing radiation hazards (Instruction 96/29/EURATOM, JOCE L-159 of 29 June 1996). This instruction does not apply to domestic radon but it is taken into consideration by another EURATOM document: the recommendation of the Commission 90/143/EURATOM of 21 February 1990 (JOCE L-80 of 27 March 1990). The present paper aims at establishing in accordance to European Union provisions the guidelines for radon risk management in working places, as well as in dwelling houses, where the implied risk is taken into account. This document does not deal with cases of high radon concentration on sites where fabrication, handling or storage of radium sources take place. These situations must be treated by special studies

  10. Mechanisms of radon injury

    International Nuclear Information System (INIS)

    Cross, F.T.

    1988-01-01

    In this new project, they conduct molecular, cellular and whole-animal research relevant to understanding the inhalation toxicology of radon and radon-daughter exposures. The work specifically addresses the exposure-rate effect in radon-daughter carcinogenesis; the induction-promotion relationships associated with exposure to radon and cigarette-smoke mixtures; the role of oncogenes in radon-induced cancers; the effects of radon on DNA as well as on DNA repair processes; and the involvement of growth factors and their receptors in radon-induced carcinogenesis. Preliminary experiments showed that oncogenes are activated in radon-induced lung tumors. They have therefore begun further exposures pertinent to the oncogene and growth-factor studies. An in vitro radon cellular-exposure system was designed, and cell exposures were initiated. Initiation-promotion-initiation studies with radon and cigarette-smoke mixtures have also begun; and they are compiling a radon health-effects bibliography

  11. Study of radon 222 permeation through plastic membranes. Application to a measurement method of radon in water

    International Nuclear Information System (INIS)

    Labed, V.; Rannou, A.; Robe, M.C.

    1990-01-01

    Gaseous permeation is a complex phenomenon of gas transfer through some polymers. Original in respect of conventional studies where permeation occurs between two gaseous phases, the present study concerns radon 222 transfer between water and air through a membrane. Polypropylene membranes are tested with an experimental device following time evolution of the phenomenon by measurement of volume activity in water and in air. An application of this study to a method for determination of radon concentration in water by measurement of concentration in air is discussed [fr

  12. Utilization of rice husk ash to enhance radon resistant potential of concrete

    International Nuclear Information System (INIS)

    Jain, Ravinder; Kant, Krishan; Yadav, Mani Kant; Chauhan, R.P.

    2013-01-01

    The radiological and health implication posed by radon and their decay products are well known. The soil containing varying amount of radionuclides is the primary source of indoor radon. The indoor radon level depends upon its entrance through the pores of the ground and floor. Thus it is necessary to restrict the radon from soil to enter indoors by application of materials with low radon diffusion coefficient. The method used for radon shielding purpose in present study utilizes the rice husk ash for substitution with cement to achieve low diffusion coefficient. The study describes the method to optimize the condition of preparation of rice husk ash using X-ray diffraction and fluorescence spectroscopy techniques. The rice husk substitution with cement was optimized by compressive and porosity test of concrete cubes. The diffusion coefficient through concrete modified by rice husk ash was carried out by scintillation radon monitor and specially design radon diffusion chamber. The radon exhalation rates from concrete carried out using active technique decreasing radon emanation from concrete with increase of rice husk ash. The result of present study suggest substitution of 20-30% rice husk ash with cement to achieve lower radon diffusion and exhalation rates with higher compressive strength as compared to control concrete. (author)

  13. Radon and radon progeny in 70 houses in the Tennessee Valley area: study design and measurement methods

    International Nuclear Information System (INIS)

    Dudney, C.S.; Hawthorne, A.R.; Monar, K.P.; Quillen, J.L.; Clark, C. Jr.; Doane, R.W.; Wallace, R.G.; Reed, R.P.

    1986-01-01

    Levels of radon and its short-lived airborne progeny are being measured in a year-long study of 70 houses in four states in the Tennessee Valley. Various methods were used to solicit volunteers with differing degrees of success. Criteria for selection of houses in the study included presence of a lower level with cement floor and one or more block walls in contact with the soil, absence of obvious indications of technologically enhanced sources of radium, and proximity to one of four cities, (Knoxville, Chattanooga, Birmingham, or Florence). By design, most houses in the study are in the same neighborhood as at least one other house in the study. Houses range in age from newly constructed to about 40 years old. Most of the houses have more than 2000 square feet of finished floor space. The lower level encompasses a garage in most cases. More complete information pertaining to house characteristics will be gathered in the course of the study. Measurements are being made to obtain information on both location- and season-dependent variation of radon and radon progeny. Simultaneous measurements are made quarterly on both upper and lower levels of each house. Grab samples of air are collected and analyzed for radon using a modified Lucas cell technique. Short-term (10-minute) samples of airborne particulate material are collected and analyzed for radon progeny. One-week integrated measurements of working levels are made once each quarter using modified thermoluminescent dosimeters. Both three- and twelve-month integrated measurements of radon using track-etch monitors are being made. 19 references, 1 figures

  14. A study of the dilution potential of the planetary boundary layer over India and adjoining oceans using radon measurements

    International Nuclear Information System (INIS)

    Rangarajan, C; Eapen, C.D.

    1990-01-01

    A comparison is made of the dilution potential of the Planetary Boundary Layer (PBI) at surface and high altitude locations in India and over the oceans of the Arabian Sea, Bay of Bengal region, using radon as a tracer. The significant difference in the diffusive properties of the PBL at these locations and their variations through the seasons are discussed and the use of these studies for plant siting pointed out. (author)

  15. Study of radon emanation from uranium mill tailings. Relations between radon emanating power and physicochemical properties of the material

    International Nuclear Information System (INIS)

    Pellegrini, D.

    1999-01-01

    The uranium extraction from ores leads to large amounts of mill tailings still containing radionuclides, such as thorium-230 and radium-226, which generate radon-222. Without protective action, radon exposition may be high enough to cause concern for health of populations living in the vicinity of an uranium mill tailings disposal. This exposition pathway has therefore to be taken into account in the radiological impact studies. The emanating power, i.e. the part of radon atoms which escape from the solid particles, is directly involved in the radon source term evaluation. It may be determined for a given material by laboratory measurements. Emanating powers from 0.08 to 0.33 have been obtained for mill tailings from Jouac (Limousin, France), at various moisture contents. In order to reduce the relations of dependence between some of the emanation parameters, more simple phases, kaolinite and polymeric resins, have been studied. Those experiments have led us to the selection of the mechanisms and the parameters to consider for the development of an emanation modelling. The whole of the results obtained point out the radon sorption, in various proportions depending on the materials. The moisture content influence on the emanation from materials containing fine particles have been confirmed: the emanation increases with this parameter until a continuous water film surrounding the particles have been formed, and then become constant. This 'water effect' occurs in a moisture content range, which depends on the material porosity. Elsewhere, the presence of amorphous phases may led to a high radon emanation. (author)

  16. Determination of equilibrium factor between radon and its progeny using surface barrier detector for various shapes of passive radon dosimeters

    International Nuclear Information System (INIS)

    Jamil, K.; Fazal-ur-Rehman; Ali, S.; Khan, H.A.

    1997-01-01

    In the field of radon dosimetry, it is customary to measure radon ( 222 Rn) concentration while potential health hazard is due to the radon short-lived progeny. When radon is in secular equilibrium, the measured activity of radon equals the activity of radon's progeny. However, in practical cases an inequilibrium between radon and its progeny exists which is measured in terms of the equilibrium factor. To determine the equilibrium factor between radon and its progeny in a closed environment various shapes of passive dosimeters based upon solid state nuclear track detectors (SSNTDs) are employed. In order to observe the dependence of equilibrium factor upon shapes or effective volumes, experiments have been performed replacing the SSNTDs with a surface barrier detector in Karlsruhe diffusion chamber, pen-type and box-type dosimeters. Using the collected alpha spectra, the equilibrium factor has been determined for a radon-air mixture in a custom designed radon chamber simulating a closed environment of a room. The results show that the radon equilibrium factor is about 0.20 for different shapes of dosimeters studied in this research. It is concluded that the determination of equilibrium factor between radon and its progeny does not depend upon effective volume or shape of the passive dosimeters using alpha spectroscopic data acquired by surface barrier detector. (orig.)

  17. Radon movement simulation in overburden by the 'Scattered Packet Method'

    International Nuclear Information System (INIS)

    Marah, H.; Sabir, A.; Hlou, L.; Tayebi, M.

    1998-01-01

    The analysis of Radon ( 222 Rn) movement in overburden needs the resolution of the General Equation of Transport in porous medium, involving diffusion and convection. Generally this equation was derived and solved analytically. The 'Scattered Packed Method' is a recent mathematical method of resolution, initially developed for the electrons movements in the semiconductors studies. In this paper, we have adapted this method to simulate radon emanation in porous medium. The keys parameters are the radon concentration at the source, the diffusion coefficient, and the geometry. To show the efficiency of this method, several cases of increasing complexity are considered. This model allows to follow the migration, in the time and space, of radon produced as a function of the characteristics of the studied site. Forty soil radon measurements were taken from a North Moroccan fault. Forward modeling of the radon anomalies produces satisfactory fits of the observed data and allows the overburden thickness determination. (author)

  18. Measurements of radon and chemical elements: Popocatepetl volcano; Mediciones de radon y elementos quimicos: Volcan Popocatepetl

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Armienta, M.A.; Valdes, C.; Mena, M. [IGFUNAM, Ciudad Universitaria, 04510 Mexico D.F. (Mexico); Seidel, J.L.; Monnin, M. [UMR 5569 CNRS Hydrosciences, Montpellier (France)

    2002-07-01

    The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

  19. The radon anomaly of Porcheresse (Ardennes, Belgium). A case study

    International Nuclear Information System (INIS)

    Charlet, J.M.; Zhu, H.C.; Poffijn, A.

    1999-01-01

    From a very high radon concentration in a dwelling of the village of Porcheresse (Belgium), the paper discusses on of the significance of the numerous radon indoor anomalies detected in the Southern part of Belgium

  20. A study of Radon-Concentration Distribution in Buildings in Gyeong-ju

    Energy Technology Data Exchange (ETDEWEB)

    Park, C. H.; Jang, S. Y.; Jung, O. J.; Moon, J. H. [Dongguk University, Gyeongju (Korea, Republic of)

    2010-10-15

    Radon({sup 222}Rn) gas is the natural radiation generated by radioactive decay of uranium({sup 238}U) nuclide. The radon which exists in ground flows into the inside by the atmospheric temperature, the differential-pressure or a gap of building underground and a ejection by a drywall with a phosphoric In Korea, Korean Institute of Nuclear Safety had been studied about the inside-radon radioactivity investigation over the nation. In the area around the nuclear power plant, it is possible to exist both of a radioactivity nuclide and a natural. Therefore it is necessary to investigate the radon radioactivity in surrounding area of nuclear power plants. In this study, it is purpose to develop the method of establishing the on-line monitoring system to minimize the radiological effect due to radon gas, based on the real state of radon exposure in Gyeong-ju surrounding Nuclear Power Plant

  1. Behaviors of radon in indoor environment

    International Nuclear Information System (INIS)

    Mochizuki, Sadamu; Shimo, Michikuni.

    1987-01-01

    The source of radon ( 222 Rn) in the atmosphere is radioactive nuclide, uranium ( 238 U), which exists fairly common throughout the earth's crust. Radium ( 226 Ra) descended from uranium produce radon ( 222 Rn) of noble gas by decay. After formation in the ground, radon diffuses into the atmosphere. Without exception radon decay products are heavy metals which soon become attached to natural aerosols. Therefore, radon and its daughters (decay products) appear also in indoor environment, and generally, their concentration levels become higher than that of outdoor air due to build-up effects in the closed indoor environments. With the progress of the study on the influence of radon and its daughers on human health, it has become clear that they act effectively as an exciting cause of lung cancer. So, the study on the risk evaluation of them in room air has become to be very important. Concequently, the behaviors of radon and its daughters in indoor environment, first of all, should be studied in detail for the accurate estimation of the risk caused by them. In this special edition, fundamental characteristics of radon and its daughters, some measuring methods, theoretical considerations and some observational evidences obtained from various circumstances of indoor environment are described inorder to grasp and understand the behaviors of radon and its daughters in the indoor environment. (author)

  2. Theoretical and experimental study of radon measurement with designing and calibration domestic canister with active charcoal

    International Nuclear Information System (INIS)

    Urosevic, V.; Nikezic, D.; Zekic, R.

    2005-01-01

    Radon concentration in air may change significantly large variation due to atmospheric variation. Measurement with active charcoal can be inaccurate because the variation in radon concentration. We made model to simulate radon measurements with active charcoal in order to optimize and improve integration characteristic. A numerical method and computer code based on the method of finite elements is developed for the case of variable radon concentration in air. This program simulates radon adsorption by the activated charcoal bed, enabling determination of sensitivity. The dependence of sensitivity on different parameters, such as temperature, thickness of the charcoal, etc. was studied using this program. Using results of theoretical investigation we designed and calibrated our canister with active charcoal for radon measurements. (author)

  3. Study on radon and thoron levels in different types of granitic work industries around Tumkur city

    International Nuclear Information System (INIS)

    Nagabhushan, S.R.; Ningappa, C.; Srilatha; Shekar, Usha; Sannappa, J.

    2011-01-01

    Radon is a naturally occurring radioactive noble gas generated by the decay of uranium and thorium bearing minerals in rocks, soils and building materials. Radon and decay products are the major contributors to human exposure from natural radiation sources. Epidemiological evidence indicates that indoor radon and thoron were responsible for a substantial number of lung cancer in publics. UNSCEAR reported recently indicates that there is a remarkable coherence between the risk estimates developed from epidemiological studies from miners and residential case-control radon studies. Hence to select the study area for the estimation of dose due to radon and thoron to the publics and workers, concentration of radon, thoron and their progeny were measured by using SSNTD. Since, activity concentration in granite more, higher concentrations of radon and thoron have been observed in the dwellings near to granite industry and lesser concentration of radon and thoron have been observed in the dwellings near brick industries of Tumkur city. From the study, the concentration of radon and thoron varied from 31 to 70.4 Bq.m 3 and 11.6 to 46.3 Bq.m 3 , respectively. Corresponding progeny level varied from 0.11 to 2.5 mWL and 1.1 to 3.4 mWL, respectively. (author)

  4. A passive monitor for radon using electrochemical track etch detector

    International Nuclear Information System (INIS)

    Massera, G.E.; Hassib, G.M.; Piesch, E.

    1980-01-01

    A passive, inexpensive monitor for radon detection and dosimetry is described in detail. It consists of a Makrofoil track etch detector inside a diffusion chamber which is sealed by a fibreglass filter through which radon may diffuse while radon daughters and aerosols are retained on the surface of the filter. The α-particle tracks are revealed by etching the Makrofoil in KOH. The lower detection limit of the radon dosimeter is equivalent to a mean dose in the lung of 130 mrem. After an exposure period of 3 months, a mean radon concentration of 0.3 pCi/l can be detected. The instrument is intended for use in a study to measure the long-term radon exposure in buildings in West Germany. (UK)

  5. Theoretical calculation on CR-39 response for radon measurements and optimum diffusion chambers dimensions

    Energy Technology Data Exchange (ETDEWEB)

    Askari, H.R.; Ghandi, Kh. [Department of Physics, Faculty of Science, Vali-e-Asr University, Rafsanjan 7713936417 (Iran, Islamic Republic of); Rahimi, M. [Department of Physics, Faculty of Science, Vali-e-Asr University, Rafsanjan 7713936417 (Iran, Islamic Republic of)], E-mail: rahimi_bam@yahoo.com; Negarestani, A. [International Center for Science and High Technology and Environmental Sciences, Kerman (Iran, Islamic Republic of)

    2008-11-11

    One method to measure radon gas concentration in the air with a long time of radiation is trace chemical etching technique. There is a direct proportion between the number of traces on solid-state nuclear track detectors (SSNTDs) and activity concentration of radon. In this paper, calibration constant for a cylindrical chamber with CR-39 detector has been measured analytically. Using this measurement, trace curves on the base of concentration for chambers with different heights and radii have been drawn. The results show that to measure radon gas concentration, the optimum chamber should have a height between 3.5 and 4 cm and a radius between 2.5 and 3.2 cm.

  6. Theoretical calculation on CR-39 response for radon measurements and optimum diffusion chambers dimensions

    International Nuclear Information System (INIS)

    Askari, H.R.; Ghandi, Kh.; Rahimi, M.; Negarestani, A.

    2008-01-01

    One method to measure radon gas concentration in the air with a long time of radiation is trace chemical etching technique. There is a direct proportion between the number of traces on solid-state nuclear track detectors (SSNTDs) and activity concentration of radon. In this paper, calibration constant for a cylindrical chamber with CR-39 detector has been measured analytically. Using this measurement, trace curves on the base of concentration for chambers with different heights and radii have been drawn. The results show that to measure radon gas concentration, the optimum chamber should have a height between 3.5 and 4 cm and a radius between 2.5 and 3.2 cm.

  7. A combined analysis of North American case-control studies of residential radon and lung cancer.

    Science.gov (United States)

    Krewski, Daniel; Lubin, Jay H; Zielinski, Jan M; Alavanja, Michael; Catalan, Vanessa S; Field, R William; Klotz, Judith B; Létourneau, Ernest G; Lynch, Charles F; Lyon, Joseph L; Sandler, Dale P; Schoenberg, Janet B; Steck, Daniel J; Stolwijk, Jan A; Weinberg, Clarice; Wilcox, Homer B

    2006-04-01

    Cohort studies have consistently shown underground miners exposed to high levels of radon to be at excess risk of lung cancer, and extrapolations based on those results indicate that residential radon may be responsible for nearly 10-15% of all lung cancer deaths per year in the United States. However, case-control studies of residential radon and lung cancer have provided ambiguous evidence of radon lung cancer risks. Regardless, alpha-particle emissions from the short-lived radioactive radon decay products can damage cellular DNA. The possibility that a demonstrated lung carcinogen may be present in large numbers of homes raises a serious public health concern. Thus, a systematic analysis of pooled data from all North American residential radon studies was undertaken to provide a more direct characterization of the public health risk posed by prolonged radon exposure. To evaluate the risk associated with prolonged residential radon exposure, a combined analysis of the primary data from seven large scale case-control studies of residential radon and lung cancer risk was conducted. The combined data set included a total of 4081 cases and 5281 controls, representing the largest aggregation of data on residential radon and lung cancer conducted to date. Residential radon concentrations were determined primarily by a-track detectors placed in the living areas of homes of the study subjects in order to obtain an integrated 1-yr average radon concentration in indoor air. Conditional likelihood regression was used to estimate the excess risk of lung cancer due to residential radon exposure, with adjustment for attained age, sex, study, smoking factors, residential mobility, and completeness of radon measurements. Although the main analyses were based on the combined data set as a whole, we also considered subsets of the data considered to have more accurate radon dosimetry. This included a subset of the data involving 3662 cases and 4966 controls with a-track radon

  8. Study of radon emanation variations in Morocco soil, correlations with seismic activities and atmospheric parameters

    International Nuclear Information System (INIS)

    Boukhal, H.; Cherkaoui, T.E.; Lferde, M.

    1994-01-01

    In order to verify the possibility of radon signal use in earthquake prediction, a study of radon emanation variation in soil was undertaken. Regular measurements have been carried out in five cities of Morocco ( Rabat, Tetouan, Ifrane, Khouribga, Berchid). The measuring method is based on the solid state nuclear track detectors technique. The good correlation between the different seismic activities and the variations of radon emanation rate in the five stations, have shown the interest of radon use in the earthquake prediction. 1 tab., 2 figs., 2 refs. (author)

  9. A 2-year study of seasonal indoor radon variations in northern Virginia

    International Nuclear Information System (INIS)

    Mose, D.G.; Mushrush, G.W.; Chrosniak, C.E.

    1991-01-01

    The concentrations of indoor radon in the basements of homes located in northern Virginia average about 1.4 times the first-floor radon concentrations. Basement indoor radon concentrations exhibit seasonal variations that can be related to home use patterns of the occupants. Little indoor radon difference was seen between homes that have concrete block basement walls and poured concrete basement walls, but homes that use oil or gas furnaces for heating have ∼ 25% lower indoor radon than homes that use electrical heating systems. Particular geological units seem to be associated with elevated indoor radon concentrations, and several units are associated with indoor radon concentrations that exceed 4 pCi/l (the U.S. Environmental Agency action level) at some time in more than 40% of the homes. Comparative studies between indoor radon and total gamma aeroradioactivity show that aeroradioactivity can be accurately used to estimate community radon hazards. When combined with information about the home heating system, geology and aeroradioactivity can be used to identify problem homes

  10. MEASUREMENTS ON, AND MODELING OF DIFFUSIVE AND ADVECTIVE RADON TRANSPORT IN SOIL

    NARCIS (Netherlands)

    VANDERGRAAF, ER; WITTEMAN, GAA; VANDERSPOEL, WH; ANDERSEN, CE; DEMEIJER, RJ

    1994-01-01

    Results are presented of measurements on radon transport in soil under controlled conditions with a laboratory facility consisting of a stainless steel vessel (height and diameter 2 m) filled with a uniform column of sand. At several depths under the sand surface, probes are radially inserted into

  11. Mass spectrometric studies of the cluster formation of radon progeny

    International Nuclear Information System (INIS)

    Gong, S.L.

    1993-01-01

    A new experimental system is developed to study the cluster formation of radon progeny with neutral molecules in the environment, which includes a modified mass spectrometer and a surface barrier detector. With the system, the cluster research is carried out at molecular level at which the mass of individual cluster formed is measured. A theory is also proposed to treat the cluster formation as a discrete process based on the ion-dipole and dipole-dipole interactions. Comparison between the theory and experiment is given. (author). 16 refs., 6 figs

  12. Mass spectrometric studies of the cluster formation of radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Gong, S L [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry

    1994-12-31

    A new experimental system is developed to study the cluster formation of radon progeny with neutral molecules in the environment, which includes a modified mass spectrometer and a surface barrier detector. With the system, the cluster research is carried out at molecular level at which the mass of individual cluster formed is measured. A theory is also proposed to treat the cluster formation as a discrete process based on the ion-dipole and dipole-dipole interactions. Comparison between the theory and experiment is given. (author). 16 refs., 6 figs.

  13. Radon as a geophysical tracer on Mars: study of its transport, first evidence and development of an instrument for its measurement

    International Nuclear Information System (INIS)

    Meslin, Pierre-Yves

    2008-01-01

    Radon-222, an inert and radioactive gas stemming from the uranium decay series, and its progeny are often used as tracers to study transfers in soils and in the atmosphere. They have also been studied on the surface of the Moon in connection with lunar outgassing. On Mars, where radon has never been studied nor measured so far, we show that their measurement could provide new insight and constraints on the chemical nature of the hydrogen measured in the Martian soil, in surface-atmosphere exchange processes, in atmospheric transport and, finally, in the dust cycle. Our approach is based on a coupled soil-atmosphere transport model implemented into the Global Circulation Model LMDZ. It includes the source term, the diffusion and adsorption of radon within the soil, and its atmospheric transport. The model input parameters are derived either experimentally (emanation factor and adsorption coefficient extrapolated to low temperatures) or by realistic models of porous media (diffusion coefficient at low pressure and as a function of the water saturation level). The model yields predictive maps of the radon exhalation rate as well as 3D fields of concentration in the soil and atmosphere, which will allow direct comparison with bismuth-214 measurements made by the GRS onboard the Mars Odyssey orbiter. We present preliminary results on this subject. An analysis of alpha spectra acquired by the APXS of the rover Opportunity is also presented, which shows evidence of a polonium-210 deposit on atmospheric dust, providing the first indirect proof of the presence of radon in the Martian atmosphere. We propose a simplified dust cycle model that enables us to infer an estimate of the global average radon exhalation rate on Mars. Lastly, we simulate the performance of an alpha spectrometer aimed at measuring radon and its progeny on the surface of the planet. (author)

  14. Study on radon concentrations in Antarctica's instrumentation and analysis

    International Nuclear Information System (INIS)

    Silva, H.E. da.

    1990-04-01

    Continuos measurements of the natural radioactive gas sup(222)Rn are made at the Brazilian Antarctic station Comandante Ferraz (62 sup(0)S, 58 sup(0)W) to study the continental influence of air masses over the Antarctic peninsula. The technique employed in the measurements is base on the process of electrostatic collection of the ionized Polonium isotopes (the Radon decay products). The efficiency of collection is of the order of 50% to 57% for an applied electric potential of 17 kV. The collection chamber has a hemispheric shape in order to optimize the collection yield. The observed radioactivity at the Ferraz station for the period March to November 1986 and 1987 exhibited different behaviors. The year 1986 showed an average radioactivity of (2.6 ± 1.8) x 10 sup(-2) Bq.m sup(-3), while in 1987 a 50% decrease in the concentration was observed with a value of (1.44 ± 0.8) x 10 sup(-2) Bq.m sup(-3). Associated variations of wind velocity and continental aerosol loads were also observed. Periodicities in the radon time series displayed more intense peaks at 25 to 30 day periods. No seasonal trend was observed. Transient increases of radon correlated with short deicing periods. The average flux of Rn were calculated from a sampling network consisting of 20 points spread over the exposed regoliths and outcrops of the King George island, with values of 250 atoms m sup(-2) s sup(-1) for the sup(220)Rn and 7500 atoms m sup(-2) s sup(-1) for the sup(222)Rn isotope. (author)

  15. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Final project report

    International Nuclear Information System (INIS)

    Hopke, P.K.

    1996-09-01

    This report completes Clarkson University's study of the chemical and physical behavior of the 218 Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. In order to pursue this general goal, two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical processes that affect the progeny's atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. Thus, two sets of specific goals have been established for this project. The specific tasks of the controlled laboratory studies are (1) Determine the formation rates of circ OH radicals formed by the radiolysis of air following radon decay; (2) Examine the formation of particles by the radiolytic oxidation of substances like SO 2 , ethylene, and H 2 S to lower vapor pressure compounds and determine the role of gas phase additives such as H 2 O and NH 3 in determining the particle size; (3) Measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and (4) Measure the neutralization rate of 218 PoO x + in O 2 at low radon concentrations

  16. A study of some factors which are related to indoor radon concentrations in Greece

    International Nuclear Information System (INIS)

    Louizi, A.; Nikolopoulos, D.; Lobotesi, E.; Mavroudaki, E.; Koukouliou, V.K.; Chanioti, M.; Papadimitriou, D.; Yiakoumakis, M.; Proukakis, C.

    1997-01-01

    The Medical Physics Department of the University of Athens is conducting radon-222 measurements in Greek dwellings. It is well known that the concentration of radon gas indoors, are related to various factors. A study of these factors has started and first results are reported. (authors)

  17. Planning meeting combined analysis, North America residential radon studies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    This report describes the Third International Department of Energy/ Commission of European Communities Workshop on Residential Radon Epidemiology held in February 1995 in Baltimore, MD. This culminates a major effort begun 1988, co-sponsored by the DOE and the CEC Radiation Protection Programme to identify and bring together all those scientists worldwide performing epidemiological case control studies of residential radon and lung cancer. Two prior meetings were held in 1989 and 1991. The goal of this effort is to work with the investigators and to pool these studies to increase their limited statistical power and to maximize any information that could be gained from them. That goal has now been met. At this Workshop the task moved from planning and agreement to implementation, as many of the studies were finally being completed and published. This report provides a summary of the Workshop as well as that of the first implementation workgroup meeting hosted by Health Canada. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  18. Overview of current radon and radon daughter research at LBL

    International Nuclear Information System (INIS)

    1983-01-01

    This report provides a brief summary of radon and radon daughter research at Lawrence Berkeley Laboratory. The radon and radon daughter research program has two broad goals: (1) the study of sources of radon and its subsequent transport into houses, and (2) research on the behavior of radon daughters in indoor environments. Additional research effort is directed to several auxiliary areas, including development of instrumentation and monitoring techniques, studies of indoor air movement, and measurement and control of indoor particulate concentrations

  19. The diffusion mechanism and convective transport in the formation of surface anomalies of RADON-222 generated at depth

    International Nuclear Information System (INIS)

    Pereira, E.B.; Hamza, V.M.

    1982-01-01

    A preliminar study on the importance of a thermally-activated convective transport of radon is made in order to explain radon anomalies at surface generated at great depth. It is theoretically shown that convective currents should be of the order of 10 μm/s or larger to explain such anomalies. The influence of surface temperature changes on the convective transport is also discussed. Seasonal changes in temperature typical of climates such as that of southern Brazil can develop thermal inversion layers at depths up to 20 metres. The optimum period of the year for the employment of surface emanometric techniques is during the second and the third months after the winter peak when the thermal inversion barriers are less intense. (Author) [pt

  20. Computer program for the sensitivity calculation of a CR-39 detector in a diffusion chamber for radon measurements

    Energy Technology Data Exchange (ETDEWEB)

    Nikezic, D., E-mail: nikezic@kg.ac.rs; Stajic, J. M. [Faculty of Science, University of Kragujevac, R. Domanovica 12, Kragujevac 34000 (Serbia); Yu, K. N. [Department of Physics and Materials Science, City University of Hong Kong, 83 Tat Chee Avenue (Hong Kong)

    2014-02-15

    Computer software for calculation of the sensitivity of a CR-39 detector closed in a diffusion chamber to radon is described in this work. The software consists of two programs, both written in the standard Fortran 90 programming language. The physical background and a numerical example are given. Presented software is intended for numerous researches in radon measurement community. Previously published computer programs TRACK-TEST.F90 and TRACK-VISION.F90 [D. Nikezic and K. N. Yu, Comput. Phys. Commun. 174, 160 (2006); D. Nikezic and K. N. Yu, Comput. Phys. Commun. 178, 591 (2008)] are used here as subroutines to calculate the track parameters and to determine whether the track is visible or not, based on the incident angle, impact energy, etching conditions, gray level, and visibility criterion. The results obtained by the software, using five different V functions, were compared with the experimental data found in the literature. Application of two functions in this software reproduced experimental data very well, while other three gave lower sensitivity than experiment.

  1. Development of a model for radon concentration in indoor air

    International Nuclear Information System (INIS)

    Jelle, Bjørn Petter

    2012-01-01

    A model is developed for calculation of the radon concentration in indoor air. The model takes into account various important parameters, e.g. radon concentration in ground, radon diffusion resistance of radon barrier, air permeance of ground, air pressure difference between outdoor ground and indoor at ground level, ventilation of the building ground and number of air changes per hour due to ventilation. Characteristic case studies are depicted in selected 2D and 3D graphical plots for easy visualization and interpretation. The radon transport into buildings might be dominated by diffusion, pressure driven flow or a mixture of both depending on the actual values of the various parameters. The results of our work indicate that with realistic or typical values of the parameters, most of the transport of radon from the building ground to the indoor air is due to air leakage driven by pressure differences through the construction. By incorporation of various and realistic values in the radon model, valuable information about the miscellaneous parameters influencing the indoor radon level is gained. Hence, the presented radon model may be utilized as a simple yet versatile and powerful tool for examining which preventive or remedial measures should be carried out to achieve an indoor radon level below the reference level as set by the authorities. - Highlights: ► Model development for calculation of radon concentration in indoor air. ► Radon model accounting for various important parameters. ► Characteristic case studies depicted in 2D and 3D graphical plots. ► May be utilized for examining radon preventive measures.

  2. Diffusive Soil Degassing of Radon and Carbon Dioxide at Ilopango Caldera, El Salvador, Central America

    Science.gov (United States)

    Ransom, L.; Lopez, D. L.; Hernandez, P.

    2001-12-01

    Ilopango Caldera lies 10 Km east of San Salvador, El Salvador and holds Ilopango Lake, the largest body of fresh water in El Salvador. There is currently no observed fumarolic activity within the caldera system. However, the last eruption occurred in 1880. In November - December, 1999, radon gas concentrations (pCi/l) were measured using a Pylon AB5 radon monitor, and flux of CO2 (g/m2/day) was determined using the accumulation chamber method at 106 sampling stations around the lake, along and across the caldera walls. Gas samples were also collected to determine the isotopic composition of C in CO2. CO2 fluxes did not show high values characteristic of other volcanic systems, values ranged from 0.7 to 9.2 g/m2/day with an average value of 3.9. These values are similar to the low values of the background population observed in nearby San Salvador volcano. Highest values are observed to the east and west of the lake. Isotopic values for C in soil gases do not show an important magmatic component. Radon concentrations present three distinct populations with the highest values occurring to the southwest. Thoron concentrations are higher close to the caldera walls than inside the caldera due to the possible higher rock fracturing in that region. Measurements taken in March 2001, after the January 13 and February 13, 2001 earthquakes did not show significant variations in CO2 fluxes. However, radon concentrations varied due to the high seismicity that lasted several months after these earthquakes. These results suggest that the magmatic system of Ilopango Caldera is not emitting high fluxes of CO2 to the atmosphere throughout the caldera soils. Subaquatic emissions of CO2 have not been evaluated. However, subaquatic hydrothermal discharges have not been identified at this calderic lake.

  3. Robustness study in SSNTD method validation: indoor radon quality

    International Nuclear Information System (INIS)

    Dias, D.C.S.; Silva, N.C.; Bonifácio, R.L.

    2017-01-01

    Quality control practices are indispensable to organizations aiming to reach analytical excellence. Method validation is an essential component to quality systems in laboratories, serving as a powerful tool for standardization and reliability of outcomes. This paper presents a study of robustness conducted over a SSNTD technique validation process, with the goal of developing indoor radon measurements at the highest level of quality. This quality parameter indicates how well a technique is able to provide reliable results in face of unexpected variations along the measurement. In this robustness study, based on the Youden method, 7 analytical conditions pertaining to different phases of the SSNTD technique (with focus on detector etching) were selected. Based on the ideal values for each condition as reference, extreme levels regarded as high and low were prescribed to each condition. A partial factorial design of 8 unique etching procedures was defined, where each presented their own set of high and low condition values. The Youden test provided 8 indoor radon concentration results, which allowed percentage estimations that indicate the potential influence of each analytical condition on the SSNTD technique. As expected, detector etching factors such as etching solution concentration, temperature and immersion time were identified as the most critical parameters to the technique. Detector etching is a critical step in the SSNTD method – one that must be carefully designed during validation and meticulously controlled throughout the entire process. (author)

  4. Robustness study in SSNTD method validation: indoor radon quality

    Energy Technology Data Exchange (ETDEWEB)

    Dias, D.C.S.; Silva, N.C.; Bonifácio, R.L., E-mail: danilacdias@gmail.com [Comissao Nacional de Energia Nuclear (LAPOC/CNEN), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas

    2017-07-01

    Quality control practices are indispensable to organizations aiming to reach analytical excellence. Method validation is an essential component to quality systems in laboratories, serving as a powerful tool for standardization and reliability of outcomes. This paper presents a study of robustness conducted over a SSNTD technique validation process, with the goal of developing indoor radon measurements at the highest level of quality. This quality parameter indicates how well a technique is able to provide reliable results in face of unexpected variations along the measurement. In this robustness study, based on the Youden method, 7 analytical conditions pertaining to different phases of the SSNTD technique (with focus on detector etching) were selected. Based on the ideal values for each condition as reference, extreme levels regarded as high and low were prescribed to each condition. A partial factorial design of 8 unique etching procedures was defined, where each presented their own set of high and low condition values. The Youden test provided 8 indoor radon concentration results, which allowed percentage estimations that indicate the potential influence of each analytical condition on the SSNTD technique. As expected, detector etching factors such as etching solution concentration, temperature and immersion time were identified as the most critical parameters to the technique. Detector etching is a critical step in the SSNTD method – one that must be carefully designed during validation and meticulously controlled throughout the entire process. (author)

  5. Study of a Greek area with enhanced indoor radon concentrations

    International Nuclear Information System (INIS)

    Louizi, A.; Nikolopoulos, D.; Koukouliou, V.; Kehagia, K.

    2003-01-01

    In this paper the focus is on Arnea Chalkidikis, an area in Greece with granitic geological background and indications of possible elevated radon concentration indoors. Data are reported of indoor radon measurements with etched track detectors and those used for dosimetric estimations. Moreover, data are reported on soil gas and soil radon concentrations in Arnea, as well as radon and uranium concentrations in water samples. From the measured radon concentrations in water samples the contribution to the overall dose has been calculated. For a period of 1 month, indoor radon and progeny activity has also been monitored in the dwelling that has the maximum indoor radon concentration in Greece. This dwelling is in Arnea and the dose delivered to the inhabitants has been calculated. Mean annual effective dose due to indoor radon was 4.5 mSv and about 11% of this was due to the use of water. Mean soil gas concentration and soil radon concentration were (90 ± 30) kBq m -3 (P -3 (P -1 (P<0.05). (author)

  6. Study of radon dispersion in typical dwelling using CFD modeling combined with passive-active measurements

    Science.gov (United States)

    Rabi, R.; Oufni, L.

    2017-10-01

    Inhalation of radon (222Rn) and its decay products are a major source of natural radiation exposure. It is known from recent surveys in many countries that radon and its progeny contribute significantly to total inhalation dose and it is fairly established that radon when inhaled in large quantity causes lung disorder. Indoor air conditions and ventilation systems strongly influence the indoor radon concentration. This study focuses on investigating both numerically and experimentally the influence of environmental conditions on the indoor radon concentration and spatial distribution. The numerical results showed that ventilation rate, temperature and humidity have significant impacts on both radon content and distribution. The variations of radon concentration with the ventilation, temperature and relative humidity are discussed. The measurement results show the diurnal variations of the indoor radon concentration are found to exhibit a positive correlation with relative humidity and negatively correlate with the air temperature. The analytic solution is used to validate the numeric results. The comparison amongst analytical, numerical and measurement results shows close agreement.

  7. Comparative study of short- and long-term indoor radon measurements

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jarallah, M.I. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)], E-mail: mibrahim@kfupm.edu.sa; Fazal-ur-Rehman,; Abdalla, Khalid [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2008-08-15

    Short-term indoor radon measurements are used widely. Therefore, it is interesting to find out a correlation between these measurements and long-term measurements which reflect a better average radon concentration of individual measurement. To find the correlation between the two measurements of indoor radon concentrations at low radon levels, a study was carried out at 34 locations of King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia using active and passive methods. In the short-term active method, a radon gas analyzer (AlphaGUARD) was used for a duration of 24 h in each measurement. In the long-term passive method, CR-39 based radon dosimeters were utilized for a period of 6 months, from January 2006 to June 2006. The short-term active measurements showed that the average, minimum and maximum radon concentrations were 19, 8 and 58Bqm{sup -3}, respectively, with a standard deviation of 8.6Bqm{sup -3}. The long-term passive measurements showed that the average, minimum and maximum radon concentrations were 25, 10 and 67Bqm{sup -3}, respectively, with a standard deviation of 12Bqm{sup -3}. The two measurements showed a poor correlation (R{sup 2}=0.38). The long-term measurements showed on the average higher concentrations by a factor of 1.3.

  8. Study of Behavior and detection of radon in environmental samples by scintillation method. Application for radium

    International Nuclear Information System (INIS)

    ZAFIMANJATO, J.L.R.

    2007-01-01

    Radon is considered as the major source of radiological exposure of natural radiations to the population. On an international scale, it represents about the half of exposures of natural radiation sources (UNSCEAR, 1993) Radon gets into human body with inhaled air and sometimes with drinking water. Then, the objective of this work is to know the radon concentrations in water and in indoor atmosphere, and the risk in order to set up a method of monitoring and to identify high radon level areas. A specific method of detection using liquid scintillation with special emphasis on α/β discrimination, the use of solvent extractive and enrichment of radionuclides have been developed for the determination of both 222 Rn and 226 Ra in water. The method is simple, rapid and sensitive. In a pilot project for a monitoring of drinking water in Madagascar, it was shown that the proposed method was suitable for a large scale monitoring and routine analysis. Considerable concentrations of radon were found in water and air samples from Vinaninkarena. Radon concentrations obtained by in situ and in laboratory measurements have been compared to the results of an international intercomparison campaigns organised by the German Society for Liquid Scintillation Spectrometry in 2011. A theoretical study of the behavior of radon is porous material containing radium is detailed in order to describe its exhalation phenomena. An assessment model of the dose due to ingestion and liberation of radon from water is presented and compared with other models especially to the Crawford Brown's model. [fr

  9. Study on radon and thoron progeny levels in Gudalore in South India

    International Nuclear Information System (INIS)

    Selvasekarapandian, S.; Sivakumar, R.; Mugunthamanikandan, N.; Meenakshisundaram, V.; Santhanam, R.

    2000-01-01

    One of the important route of radiation exposure to man is through inhalation of air containing radioisotopes. A major contribution to inhalation dose comes from radon, thoron and its progenies. The indoor radon and thoron progeny levels are determined by two count method. In this method the radon and thoron progenies are collected on a glass fiber filter paper using volume air sampler (Staplex) and counted for alpha activity in ZnS (Ag) alpha counting system. It is observed that thoron working level is higher than the radon working level in all houses except few houses with stone walls and mosaic floor. Behavior of indoor radon and thoron working levels for different seasons at different houses are determined and discussed in detail. Radon and thoron working levels are measured high in winter, autumn, and low in summer and rainy seasons. Among all seasons highest value is measured in winter and low in summer and rainy seasons. Radon progeny working level varies from 1.659 to 6.675 mWL, whereas thoron progeny working level varies from 1.670 to 12.671 mWL. The geometric mean values of radon and thoron progeny concentration in the present study are 2.836 and 4.133 mWL. The high thoron progeny level observed in this is attributed to the high thorium content observed in soils of this area. (author)

  10. Application of studies of miners to radon problem in homes

    International Nuclear Information System (INIS)

    Radford, E.P.; Clair Renard, K.G.S.

    1984-01-01

    The lung cancer risk from exposure in homes to short-lived daughters of radon-222 can be estimated from results for underground miners, if differences in epidemiologic and exposure variables between mining populations and the general public can be assessed. Our study of Swedish iron miners exposed at low dose rates and with long follow-up time has enabled us to determine smoking-specific risk coefficients, and to rule out other factors in the mine atmosphere as contributing to lung cancer risk. Miners differ from the population at large in the following characteristics: sex, age at exposure, dose rate, dust conditions in mines and homes, smoking, volume breathed per unit time and proportion of the year exposed. The last two factors affect the conversion of air concentrations to cumulative yearly doses, and from present evidence dose rate, sex and age should not alter risk factors to a great extent. For persons aged 60 about 30% of lung cancers in non-smokers may be attributed to radon daughters, and about 6% in smokers. The percentage may be higher at older ages if the relative risk is found to be constant at these ages. (Author)

  11. Uranium City radiation reduction program: further studies on remedial measures and radon infiltration routes for houses with block walls

    International Nuclear Information System (INIS)

    Leung, M.K.

    1980-01-01

    This report describes the results of tests of partial sealing of concrete block walls to prevent radon infiltration into houses in Uranium City, and gives the results of studies of radon migration through concrete block walls. Results of some laboratory tests on the effectiveness of concrete blocks as a radon barrier are included

  12. Contribution to the study of radon risk assessment - Use of Solid State Nuclear Tracks Detectors (SSNTD) for the measurement of radon in buildings

    International Nuclear Information System (INIS)

    RALAIARISOA, H.L

    2004-01-01

    222 Rn is a natural radioactive gas, originating from the decay of 226 Ra. Both of these radionuclides are elements of 238 U series. Uranium is naturally present in the rocks and soils, therefore radon is always present too because it is a soil gas. Radon takes the most important part in man exposure to natural sources of ionizing radiations. Moreover, it causes lung cancer. It can accumulate in confined environments such as buildings, so that its inhalation is a potential risk for human health. Thus radon measurement is necessary for radiation protection. Integrated measurement using Solid State Nuclear Tracks Detector (SSNTD) is a very common method for radon measurement in buildings because of the low cost of the detectors and their easy application. The measurement technics are based on the interaction of alpha particles emitted by radon with a polymer. Alpha particles produce in the polymer latent tracks, which need chemical revelation to be observable with optical microscopy. The number of revealed tracks is proportionnal to the average volumic activity of 222 Rn corresponding to the time exposure of the detectors.The aim of this thesis work is the continuation of previous study on the preliminary investigations of radon levels in the city of Antananarivo, and to extend this study in Antsirabe, which has been shown as a region of interest. The levels of radon measured in buildings in Antananarivo and Antsirabe are typical values of indoor radon concentration. The average values of concentrations are inferior to 60 Bq.m - 3. The health risk is negligible but not nul. A typical protocol of radon level measurement in Malagasy buildings is suggested to allow the implementation of a risk management policy related to radon within the Malagasy context. [fr

  13. A study of the physico-chemical characteristics of a solid radon 222 source

    International Nuclear Information System (INIS)

    Chuiton, G.

    1990-01-01

    A solid radon 222 source is described; it is made of a manganese oxide impregnated acrylic felt disc on which radium 226 is fixed. The disc is incorporated into a scanning device allowing the passage through the felt of a radon 222 free gas (air or nitrogen) previously led to a relative humidity of air near to saturation. At the device outlet, a stable activity of radon 222 is obtained. The preparation, characteristics and radiochemical stability conditions of the 226 radium source are presented. Following a description of the scanning device, the radon 222 emanation coefficient is studied as a function of the relative humidity of air. The reliability of the device is assessed by an uncertainty calculation for the utilisation conditions recommended. Finally, an approach to the physico-chemical processes governing radon 222 emanation rate in the device is set forth [fr

  14. Microclimatic effects on outdoor radon and its progeny in a long-term study

    International Nuclear Information System (INIS)

    Schuetz, M.; Keller, G.; Kappel, R.J.A.

    1994-01-01

    The dose due to the long term radon exposure is estimated from the radon concentration and from an equilibrium factor that in the literature is reported with a wide uncertainty. Therefore the radon equilibrium factor outdoors and its dependence on climatic effects should be investigated in a long-term study. Both the outdoor concentrations of radon and of its progeny near Ellweiler/Hunsrueck were measured continuously during 12 months and the resulting equilibrium factors were determined. Simultaneously to the every 2 hour's radon data many meterological parameters as temperature and relative to humidity of the air, barometric pressure and duration and amount of rainfall were recorded. At a height of 6 meters above ground and in 10 minute intervals the local wind direction and velocity were registered. By that a set of more than 3000 single measurements of the equilibrium factor and of the corresponding weather conditions was collected

  15. Studies on the migration rule and mechanism of radon and its daughters

    International Nuclear Information System (INIS)

    Jia Wenyi; Fang Fang; Zhou Rongsheng; Ma Yingjie; Qiu Yuande; Hou Xinsheng; Wu Yunping; Zu Xiulan; Wang Xiaoqin

    2000-01-01

    By using very precise, highly sensitive, static accumulated, easily repeated CD-1 α-cup, the migration rule and mechanism of radon and its daughters was studied. Significant results were obtained: (1) Under laboratory conditions, the vertical component of migration of radon and its daughters was much greater than the horizontal component, the former was over 90% and the latter was less than 10%. (2) Despite the very big specific gravity of radon and its daughters, the descending component of migration was less than 45%, while the ascending component was more than 45%. (3) After α-particles (emitted from radon and its daughters) being slowed down. 4 He combined with the radon and its daughters to form clusters. When the density of the cluster was less than that of the air, the self-ascending would occur

  16. Uranium prospecting through radon detection; La prospection de l'uranium par le radon

    Energy Technology Data Exchange (ETDEWEB)

    Pradel, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1956-07-01

    Prospecting rests on the determination of the concentration of ground air in radon. Radon diffusing from deep uranium bearing layers is detected in upper ground layers. (author) [French] La prospection est basee sur l'etude de la concentration en radon dans l'air du sol. Dans les terrains superficiels, on decele le radon qui diffuse a partir des couches profondes uraniferes. (auteur)

  17. A universal laboratory method for determining physical parameters of radon migration in dry granulated porous media.

    Science.gov (United States)

    Ye, Yong-Jun; Zhang, Yun-Feng; Dai, Xin-Tao; Ding, De-Xin

    2017-10-01

    The particle size and heaped methods of exhalation media have important effects on physical parameters, such as the free radon production rate, porosity, permeability, and radon diffusion coefficient. However, existing methods for determining those parameters are too complex, and time-consuming. In this study, a novel, systematic determining method was proposed based on nuclide decay, radon diffusion migration theory, and the mass conservation law, and an associated experimental device was designed and manufactured. The parameters of uranium ore heap and sandy soil of radon diffusion coefficient (D), free radon production rate (α), media permeability (k), and porosity (ε) were obtained. At the same time, the practicality of the novel determining method was improved over other methods, with the results showing that accuracy was within the acceptable range of experimental error. This novel method will be of significance for the study of radon migration and exhalation in granulated porous media. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Czech miner studies of lung cancer risk from radon

    International Nuclear Information System (INIS)

    Tomasek, L.

    2002-01-01

    Epidemiological evidence of lung cancer risk from radon is based mainly on studies of miners. Two such studies among Czech uranium miners were established in 1970 and 1980. A subcohort of 5002 miners and a nested-in case-control study contribute to a joint European project. In this paper, the subcohort of miners with 495 lung cancers is described. The excess relative risk depends linearly on cumulative exposure incurred more than 5 years before. The relative effect from exposures in the distant past decreases by 62% per decade. Simultaneously, the excess relative risk is lower by 43% per decade in dependence on age at exposure. The effect of smoking, partly analysed in the study, suggests a twofold elevation in the relative risk coefficient among non-smokers, but this difference is not significant. (author)

  19. Environmental radon studies using solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Singh, Surinder; Sharma, Dinesh Kumar; Kumar, Ajay

    2004-01-01

    The results of radon activity recorded in 70 dwellings of Nurpur area, Kangra district, Himachal Pradesh, India are reported. LR-115 Type 2 films in the bare mode were exposed for four seasons of three months each covering a period of one year for the measurement of indoor radon levels. The calibration constant of 0.020 tracks cm -2 d -1 per Bq m -3 has been used to express radon activity in Bq m -3 . The annual average indoor radon concentrations in 17 different villages of the area are found to vary from 168±46 to 429±71 Bq m -3 . Most of the indoor radon values lie in the range of action levels (200-600 Bq m -3 ) recommended by International Commission on Radiological Protection

  20. Radon study in underground buildings in Chongqing, China

    International Nuclear Information System (INIS)

    Deng Wen; Jiang Rende; Liu Yigang

    1993-01-01

    Radon concentration measurements using a scintillation detector were conducted in 51 large underground buildings, which have been used as hotels, entertainment halls, restaurants, shops and factories, etc, in Chongqing, China. The results showed that the radon concentrations in these underground buildings ranged from 3.2 to 616.2 Bqm -3 . The arithmetic mean was 57.6 Bqm -3 , which was about 4 times as much as the mean radon concentration in ground buildings in Chongqing. The underground buildings with the highest radon concentrations were correlated with the high content of radium-226 in building materials, mechanical ventilation through interior circulatory ducts, underground depth of the building, and particularly, fissures in the walls. Measures of radon mitigation in underground buildings were recommended. (orig.). (3 refs., 5 tabs.)

  1. Measurements of radon and chemical elements: Popocatepetl volcano

    International Nuclear Information System (INIS)

    Pena, P.; Segovia, N.; Lopez, B.; Reyes, A.V.; Armienta, M.A.; Valdes, C.; Mena, M.; Seidel, J.L.; Monnin, M.

    2002-01-01

    The Popocatepetl volcano is a higher risk volcano located at 60 Km from Mexico City. Radon measurements on soil in two fixed seasons located in the north slope of volcano were carried out. Moreover the radon content, major chemical elements and tracks in water samples of three springs was studied. The radon of soil was determined with solid detectors of nuclear tracks (DSTN). The radon in subterranean water was evaluated through the liquid scintillation method and it was corroborated with an Alpha Guard equipment. The major chemical elements were determined with conventional chemical methods and the track elements were measured using an Icp-Ms equipment. The radon on soil levels were lower, indicating a moderate diffusion of the gas across the slope of the volcano. The radon in subterranean water shown few changes in relation with the active scene of the volcano. The major chemical elements and tracks showed a stable behavior during the sampling period. (Author)

  2. Radon diffusion in polymer vessels using CR-39 solid state nuclear track detector

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Andre Cavalcanti; Menezes, Maria Angela de B.C.; Rocha, Zildete; Pereira, Marcio Tadeu, E-mail: andreccarneiro@gmail.com, E-mail: menezes@cdtn.br, E-mail: zildete@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Santos, Talita de Oliveira; Lara, Evelise Gomes; Braga, Mario Roberto Martins S.S., E-mail: mariomartins@gmail.com, E-mail: evelise.lara@gmail.com, E-mail: talitaolsantos@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2015-07-01

    At CDTN/CNEN, the method to determine {sup 226}Ra in several matrices by gamma spectrometry is already established; however, the method should be improved. This paper is about the first step of this improvement. Several polymer vessels were studied verifying the effect of radiolysis on the walls of the vessel. A test about the diffusion of {sup 222}Rn through the walls was carried out using the CR-39 solid state nuclear track detector. The results pointed out that the vessel made up by acrylic material is the best candidate to replace the vessel actually used. (author)

  3. Determination of detection efficiency for radon and radon daughters with CR 39 track detector - a Monte Carlo study

    International Nuclear Information System (INIS)

    Nikezic, D.

    1994-01-01

    The detection effciency, ρ, (or a calibration coefficient k) for radon measurements with a solid state nuclear track detector CR 39 was determined by many authors. There is a considerable discrepancy among reported values for ρ. This situation was a challenge to develop a software program to calculation ρ. This software is based on Bethe-Bloch's expression for the stopping power for heavy charged particles in a medium, as wll as on the Monte Carlo Method. Track parameters were calculated by using an iterative procedure as given in G. Somogyi et al., Nucl. Instr. and Meth. 109 (1973) 211. Results for an open detector and for the detector in a diffusion chamber were presented in this article. (orig.)

  4. Study of different factors which can explain the radon exhalation potential of soils; Recherche de differents parametres caracterisant le potentiel d`exhalation en radon des sols

    Energy Technology Data Exchange (ETDEWEB)

    Demongeot, St

    1997-10-27

    Radon is a natural radioactive gas belonging to the Uranium-238 chain, which is present in the earth crust and produced by the disintegration of radium-226. It is considered as the major source of radiological exposure of man to natural radiation because it can accumulate in indoor atmosphere. So, this health risk must be take into account.The aim of this study is to find some tools in order to identify high radon level area. The first part of this study has consisted in measurement of radon emission from different not sufficient for the estimation of the radon exhalation potential in a given area. In the second part of this work, we have studied the variations of in situ radon concentration as a function of different geological and pedologic parameters of the site. With the results obtained, we have determined the data which have to be considered, and the methodology to be applied for the determination of the radon exhalation of a given area. Furthermore, by the mean of numerical simulations (TRACH Model), it was possible to know the scale of radon flux variation in a given point versus the hydric state of the ground and thus the permeability: these parameters are not easy to measure because of their variabilities with time. The methodology ESPERAS (EStimation du Potential d`Exhalation en Radon des Sols) developed during this work was applied first, at a local scale and then to greater area. The values estimated by this way are in a good agreement with the results of measurements. So, we can determine the areas which are affected by high radon levels. (author)

  5. Radon in buildings: instrumentation of an experimental house

    International Nuclear Information System (INIS)

    Ameon, R.; Diez, O.; Dupuis, M.; Merle-Szeremeta, A.

    2004-01-01

    IRSN decided to develop a code called RADON 2 for conducting simple and methodical studies of indoor radon concentrations. Since a validity check must be performed of the phenomenological model on which the code is based, an experimental program was initiated in 2002, within which a house in Brittany, located on a well-characterized uranium-bearing geological formation, was fitted with special instruments. After characterizing the soil underlying the house, the instrumentation implemented on site continuously monitors a number of parameters to characterize: the radon source term in the building (exhalation rate of 222 Rn at the ground/building interface and at soil surface, radon concentration in the soil and in outdoor air); radon penetration by advection (differential pressure in the house basement); the driving mechanisms for natural ventilation in the house (weather conditions, indoor temperature and relative humidity); radon distribution throughout the house by air flow and radon diffusion (indoor radon concentration at each floor of the house). Using the experimental data acquired over the past two years, the phenomena governing radon penetration inside the house (wind and stack effect) and radon extraction (fresh air supply rate) have been characterized to lay down the bases for validating the newly developed code

  6. Case-control study of radon and lung cancer in New Jersey

    International Nuclear Information System (INIS)

    Wilcox, H. B.; Al-Zoughool, M.; Garner, M. J.; Jiang, H.; Klotz, J. B.; Krewski, D.; Nicholson, W. J.; Schoenberg, J. B.; Villeneuve, P. J.; Zielinski, J. M.

    2008-01-01

    Radon is known to cause lung cancer in humans; however, there remain uncertainties about the effects associated with residential exposures. This case-control study of residential radon and lung cancer was conducted in five counties in New Jersey and involved 561 cases and 740 controls. A yearlong α-track detector measurement of radon was completed for ∼93% of all residences lived in at the time of interview (a total of 2063). While the odds ratios (ORs) for whole data were suggestive of an increased risk for exposures >75 Bq m -3 , these associations were not statistically significant. The adjusted excess OR (EOR) per 100 Bq m -3 was -0.13 (95% CI: -0.30 to 0.44) for males, 0.29 (95% CI: -0.12 to 1.70) for females and 0.05 (95% CI: -0.14 to 0.56) for all subjects combined. An analysis of radon effects by histological type of lung cancer showed that the OR was strongest for small/oat cell carcinomas in both males and females. There was no statistical heterogeneity of radon effects by demographic factors (age at disease occurrence, education level and type of respondent). Analysis by categories of smoking status, frequency or duration did not modify the risk estimates of radon on lung cancer. The findings of this study are consistent with an earlier population-based study of radon and lung cancer among New Jersey women, and with the North American pooling of case control radon seven studies, including the previous New Jersey study. Several uncertainties regarding radon measurements and assumptions of exposure history may have resulted in underestimation of a true exposure-response relationship. (authors)

  7. Study of different factors which can explain the radon exhalation potential of soils

    International Nuclear Information System (INIS)

    Demongeot, St.

    1997-01-01

    Radon is a natural radioactive gas belonging to the Uranium-238 chain, which is present in the earth crust and produced by the disintegration of radium-226. It is considered as the major source of radiological exposure of man to natural radiation because it can accumulate in indoor atmosphere. So, this health risk must be take into account.The aim of this study is to find some tools in order to identify high radon level area. The first part of this study has consisted in measurement of radon emission from different not sufficient for the estimation of the radon exhalation potential in a given area. In the second part of this work, we have studied the variations of in situ radon concentration as a function of different geological and pedologic parameters of the site. With the results obtained, we have determined the data which have to be considered, and the methodology to be applied for the determination of the radon exhalation of a given area. Furthermore, by the mean of numerical simulations (TRACH Model), it was possible to know the scale of radon flux variation in a given point versus the hydric state of the ground and thus the permeability: these parameters are not easy to measure because of their variabilities with time. The methodology ESPERAS (EStimation du Potential d'Exhalation en Radon des Sols) developed during this work was applied first, at a local scale and then to greater area. The values estimated by this way are in a good agreement with the results of measurements. So, we can determine the areas which are affected by high radon levels. (author)

  8. Outlines of a study of some indicators of exposure of underground workers to radon in Slovakia

    Energy Technology Data Exchange (ETDEWEB)

    Beno, M; Nikodemova, D; Vladar, M; Fueloep, M; Vicanova, M [Inst. of Preventive and Clinical Medicine, Bratislava (Slovakia)

    1996-12-31

    In this paper some indicators of exposure of underground workers to radon in Slovakia which will be used for determination of miners radiation burden and for the radon dose estimate was explained. The projected study has a dose-effect scaffold and its projected goals are on the side of dose assessment: 1) to determine the professional exposure of underground workers to radon by personal dosimetry and to establish a database of integrated personal doses for future epidemiological studies; 2) to introduce the method of counting the radionuclide {sup 210}Pb in the bones and skulls of underground workers. On the side of effect assessment the goals are: 1) to find out if a dependence of the number of chromosomal aberrations (CA) and micronuclei in the lymphocytes from radon dose exists. The measurements of radon in mines, preferentially those by personal dosimeters as well as an existing database of radon concentration measurements in dwellings and caves will serve for the radon dose estimate; 2) to compare the DNA-repair rate in the lymphocytes of people professionally exposed to radon in Slovak caves with the same rate as assessed in unexposed people; 3) to find out the proportional role of confounding factors such as smoking, alcohol abuse, exposure to dust etc., which might influence upon the interpretation of the dose from radon to health response relationship; 4) to establish a central database of lung cancer cases in professionally exposed underground workers for future epidemiological studies. The direct method will rely upon determination of miners radiation burden based on the {sup 210}Pb activity deposited in skeleton. The experimental design to assess the effects will have three main methodological parts: 1) determination of the count of chromosomal aberrations and micronuclei using classical methods; 2) determination of the chromosomal changes using the fluorescent in situ hybridization method; 3) determination of the DNA-repair rate. (J.K.) 8 refs.

  9. Earthquake precursory studies in Kangra valley of North West Himalayas, India, with special emphasis on radon emission

    International Nuclear Information System (INIS)

    Kumar, Arvind; Singh, Surinder; Mahajan, Sandeep; Bajwa, Bikramjit Singh; Kalia, Rajeev; Dhar, Sunil

    2009-01-01

    The continuous soil gas radon monitoring is carried out at Palampur and the daily monitoring of radon concentration in water is carried out at Dharamshala region of Kangra valley of North West Himalayas, India, a seismic zone V, to study the correlation of radon anomalies in relation to seismic activities. In this study, radon monitoring in soil was carried out by using barasol probe manufactured by Algade France, whereas the radon content in water was recorded using RAD 7 radon monitoring system of Durridge Company USA. The effect of meteorological parameters viz. temperature, pressure, wind velocity, rainfall, and humidity on radon emission has been studied. The seasonal average value and standard deviation of radon in soil and water is calculated to find the radon anomaly to minimize the effect of meteorological parameters on radon emission. The radon anomalies observed in the region have been correlated with the seismic events of M≥2 reported by Wadia Institute of Himalayas Geology Dehradoon and Indian Meteorological Department, New Delhi in NW Himalayas within 250 km distance from the monitoring stations.

  10. RADON MITIGATION IN SCHOOLS: CASE STUDIES OF RADON MITIGATION SYSTEMS INSTALLED BY EPA IN FOUR MARYLAND SCHOOLS ARE PRESENTED

    Science.gov (United States)

    The first part of this two-part paper discusses radon entry into schools, radon mitigation approaches for schools, and school characteristics (e.g., heating, ventilation, and air-conditioning -- HVAC-- system design and operation) that influence radon entry and mitigation system ...

  11. A study on surveillance of environmental factors affecting the variation of indoor radon concentration

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Shin Ae; Kim, Ok Ja; Lee, Mi Kyeong; Cho, Eun Ok; Choi, Yun Sun; Choi, Jin Kyeong; Park, Seon Hye; Han, Hyeon Sun [Hankook Research, Seoul (Korea, Republic of)

    2000-03-15

    Before the main survey, a preliminary survey was carried out to decide the most suitable type of a radon detector the most appropriate places to install such a radon detector. To this end, three types of detectors were set up in 108 locations, approximately 3% of 3,000 to measure the radon levels, and 102 detectors(94%) were collected. As a result of the preliminary survey, Radtrack was chosen as a radon detector for the main survey, and bedrooms on the first floor of houses and the first floor of public buildings were decided to be the places for the first installment of detectors. It is most desirable to survey the radon concentrations in all houses nationwide. Considering the survey period and budgets, however, 3,000 spots were targeted for the main survey at the recommendation of the Korea Institute of Nuclear Safety in charge of this study. As it is important to maintain the same panels for a year to measure the radon concentrations at 3,000 locations, a total of 3,237 panels, 10% more than the target sample number, were surveyed considering the possible loss of panels during the survey period. The first radon detector was installed in each of 3,237 spots in December 1999, and collected three months later in March 2000, followed by the installment of the second detector.

  12. Is environmental radon gas associated with the incidence of neurodegenerative conditions? A retrospective study of multiple sclerosis in radon affected areas in England and Wales

    International Nuclear Information System (INIS)

    Groves-Kirkby, Christopher J.; Denman, Antony R.; Campbell, Jackie; Crockett, Robin G.M.; Phillips, Paul S.; Rogers, Stephen

    2016-01-01

    To test whether an association exists between radon gas concentration in the home and increased multiple sclerosis (MS) incidence, a retrospective study was undertaken of MS incidence in known areas of raised domestic radon concentration in England and Wales, using The Health Improvement Network (THIN) clinical research database. The study population comprised 20,140,498 person-years of clinical monitoring (males: 10,056,628: 49.93%; females: 10,083,870: 50.07%), representing a mean annual population of 2.5 million individuals. To allow for the possible latency of MS initiation following exposure, data extraction was limited to patients with at least five years registration history with the same GP practice before first diagnosis. Patient records were allocated to one of nine radon concentration bands depending on the average radon level in their postcode sector. MS incidence was analysed by searching for patients with first MS diagnosis over the eight calendar years 2005–2012 inclusive. 1512 new MS cases were diagnosed, 1070 females, 442 males, equivalent to raw incidence rates of 7.51, 10.61 and 4.40 per 10 5 person-years respectively, comparable to previously reported results. Of these new cases, 115 could be allocated to one of the radon bands representing high radon areas. Standardising to the UK 2010 population, excess relative risk (ERR) figures for MS were calculated for each radon band. Linear regression of ERR against mean band radon concentration shows a positive gradient of 0.22 per 100 Bq·m −3 (R 2  = 0.25, p = 0.0961) when forced through the origin to represent a linear-no-threshold response. The null hypothesis falls inside the 95% confidence interval for the linear fit and therefore this fit is not statistically significant. We conclude that, despite THIN sampling around 5% of the population, insufficient data was available to confirm or refute the hypothesised association between MS incidence and radon concentration. - Highlights:

  13. Models for retrospective quantification of indoor radon exposure in case-control studies

    International Nuclear Information System (INIS)

    Gerken, M.; Kreienbrock, L.; Wellmann, J.; Kreuzer, M.; Wichmann, H.E.

    2000-01-01

    In epidemiologic studies on lung cancer risk due to indoor radon the quantification of individual radon exposure over a long time period is one of the main issues. Therefore, radon measurements in one or more dwellings, which in total have been inhabited by the participants for a sufficient time-period, are necessary as well as consideration of changes of building characteristics and ventilation habits, which influence radon concentration. Given data on 1-y alpha-track measurements and personal information from 6,000 participants of case-control studies in West and East Germany, and improved method is developed to assess individual radon exposure histories. Times spent in different rooms of the dwelling, which are known from a personal questionnaire, are taken into account. The time spent outside the house varies substantially among the participants. Therefore, assuming a substantially lower radon exposure outside the dwelling, the residence time constitutes an important aspect of total radon exposure. By means of an analysis of variance, important determinants of indoor radon are identified, namely constant conditions such as type of house, type of construction, year of construction, floor and type of basement, and changeable conditions such as heating system, window insulation, and airing habits. A correction of measurements in former dwellings by factors derived from the analysis is applied if current living conditions differ from those of the participants at the time when they were living in the particular dwellings. In rare cases the adjustment for changes leads to a correction of the measurements with a factor of about 1.4, but a reduction of 5% on average only. Exposure assessment can be improved by considering time at home and changes of building and ventilation conditions that affect radon concentration. The major concern that changes in ventilation habits and building conditions lead to substantial errors in exposure assessment cannot be confirmed in the

  14. A study on the environmental behavior of global air pollutants based on the continuous measurements of atmospheric radon concentrations

    International Nuclear Information System (INIS)

    Iida, Takao; Yamazawa, Hiromi

    2003-01-01

    Radon is a useful natural radioactive tracer of air transportation of atmospheric pollution, since radon is a noble gas and chemically inert. The atmospheric radon concentration is usually measured by a high-sensitivity electrostatic collection method or a two-filter method. The variations of radon concentrations observed over a solitary island and in the upper atmosphere are suitable for comparing with those of air pollutants. Some numerical simulation models were used to study the radon global transport in the atmosphere. In East Asia, atmospheric radon and air pollutants are transported with the air stream from the continent of China to the Northwestern Pacific Ocean. It is necessary to clarify the transport mechanism from both radon observations at various locations and numerical simulation. (author)

  15. Radon dose and aerosols

    International Nuclear Information System (INIS)

    Planinic, J.; Radolic, V.; Faj, Z.; Vukovic, B.

    2000-01-01

    The equilibrium factor value (F) was measured in the NRPB radon chamber and the corresponding track density ratio (r = D/D 0 ) of bare (D) and diffusion (D 0 ) LR-115 nuclear track detectors was determined, as well as the regression equation F(r). Experiments with LR-115 nuclear track detectors and aerosol sources (burning candle and cigarette) were carried out in the Osijek University radon chamber and afterwards an empirical relationship between the equilibrium factor and aerosol concentration was derived. For the purpose of radon dose equivalent assessment, procedures for determining the unattached fraction of radon progeny were introduced using two nuclear track detectors. (author)

  16. Public perceptions of radon risk

    International Nuclear Information System (INIS)

    Mainous, A.G. III; Hagen, M.D.

    1993-01-01

    Since 1984, a significant amount of media attention has focused on health threats from radon gas exposure. Using a probability telephone survey of adults (n = 685), we studied public perceptions of risk from radon exposure versus other environmental health risks. The results indicated that 92% of those individuals who had heard of radon believe radon to be a health risk, although only 4% believe they are currently exposed to high levels of radon gas. Perception of risk from radon was positively related to other perceptions of environmental risks. Younger and less educated individuals were more likely to perceive radon as a health risk. Women were three-and-one-half times as likely as men to perceive risk from radon. However, there was no significant relationship between perceived risk from radon and cigarette smoking. Media attention has apparently led to public awareness of radon hazards, but further attention is needed to improve smokers' awareness of their special risks from radon

  17. Studying the possibility of recharging E-Perm for radon measurement in air

    International Nuclear Information System (INIS)

    Shweikani, R.; Bardan, R.

    2011-03-01

    In this work recharging electret detectors and studying their responding for radioactive gases (radon gas) was studied and the results were compared with solid state nuclear detectors (CR-39). After several experiments we found that using a metal nozzle which is connected to a high voltage supply (poling method) was useful to polarize the electret material and get a stable electrostatic charge. The stability of electret was studied after each experiment ,the results showed that the best charging parameters were: (7 mm as a nozzle height.- 15 sec as a charging time.- 5 kV as a charging voltage). Depending on the charging and stability studying results the electrets were calibrated in radon calibration cell and the calibration factors were defined The charged electrets were examined to measure radon concentration in the open environmental and were compared with CR-39 detectors; the charged electrets appeared a liner response for radon gas as CR-39 detectors.(author)

  18. Study on the influence of CR-39 detector size on radon progeny detection in indoor environments

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L. A.; Hadler, J. C.; Lixandrão F, A. L.; Guedes, S.; Takizawa, R. H. [Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas, SP (Brazil)

    2014-11-11

    It is well known that radon daughters up to {sup 214}Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based on the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination.

  19. Geochemical studies of potential source minerals of radon: case studies in Hungary

    Energy Technology Data Exchange (ETDEWEB)

    Rajnai, G.; Nagy-Balogh, J.; Gal-Solymos, K.; Konc, Z.; Breitner, D.; Barabas, A.; Szabo, C. [Eotvos Univ., Lithosphere Fluid Research Lab, Dept. of Petrology and Geochemistry, Budapest (Hungary); Barabas, A. [Eotvos Univ., Dept. of Geophysics, Budapest (Hungary)

    2006-07-01

    In Hungary, during the past decade five distinct regions have been chosen to find possible explanations of the uncommonly high radon background radiation values. The main aim of the research is to study U- and Th-bearing minerals in petrographic and geochemical characters. Besides the microscopic techniques, whole rock and in situ geochemical analytical methods were applied to determine the bulk U and Th content of the studied geological samples. We assume that some of the radon measured is related to the U and Th contents of the samples. (authors)

  20. A study of radon 222 permeation through plastic membranes. Application to a method of radon measurement in water and saturated soils

    International Nuclear Information System (INIS)

    Labed, V.

    1991-04-01

    In order to improve the BARASOL R device and to use it in water-saturated soils and in pressure constraint conditions, we have studied radon 222 permeation through plastic membranes. While the permeation process usually takes place between two media being in the same state, most often gaseous, the present study describes the transfer of radon 222 from the water to the air via a membrane. Polypropylene membranes have been tested with an experimental set-up by monitoring the evolution of radon concentrations in water and in air. The permeation coefficient and the activation energy were calculated in various conditions. With a second experimental set-up, we have tested the polyethylene membrane which has been adapted on the BARASOL. In these conditions, we have shown that it is possible to measure radon in water at concentrations around 10 3 Bq.m -3 [fr

  1. A study of radon activity inside some houses in Bangladesh

    International Nuclear Information System (INIS)

    Islam, G.S.; Islam, M.A.; Farid, S.M.; Rahman, A.

    1988-01-01

    The solid state nuclear track detector CR-39 has been used for long term measurements of the radon-222 emanation from building materials and the resultant activity inside houses in Bangladesh. Particular attention is paid to a special type of house with thick walls made entirely of mud. The radon-exhalation rate of the walls of these mud-built houses is found to be consistently higher than that of brick-built houses. (author)

  2. Paloma-radon: Atmospheric radon-222 as a geochemical probe for water in the Martian subsoil.

    Science.gov (United States)

    Sabroux, J.-C.; Michielsen, N.; Voisin, V.; Ferry, C.; Richon, P.; Pineau, J.-F.; Le Roulley, J.-C.; Chassefière, E.

    2003-04-01

    Radon exhalation from a porous soil is known to depend strongly on the soil moisture content: a minute amount of water, or water ice, in the pore space increases dramatically the possibility for radon to migrate far from its parent mineral. We propose to take advantage of this characteristic by using atmospheric radon-222 as a geochemical probe for water in the Martian soil, at least one order of magnitude deeper than the current Mars Odyssey neutron data. Strong thermal inversions during the Martian night will accumulate radon in the lowest atmospheric boundary layer, up to measurable levels despite the comparatively high environmental (cosmic and solar) background radiation and the assumed low uranium content of the upper crust of the planet. Preliminary studies and development of an instrument for the measurement of the Martian atmospheric alpha radioactivity is part of the CNES-supported PALOMA experiment. Two test benches have been implemented, one of them allowing differential measurements of the diffusion of radon in the Martian soil simulant NASA JSC Mars-1, under relevant temperatures and pressures. The other, a 1 m^3 radon-dedicated test bench, aims to characterize the instrument that will measure radon in the Mars environment (7 mb CO_2). Tests on several nuclear radiation detectors show that semiconductor alpha-particle detectors (PIPS) are the best option (already on board the Mars Pathfinder Rover and other platforms). In addition, the detection volume is left open in order to capitalize upon the long (ca. 4 m) alpha track at this low pressure. A stationary diffusion model was developed in order to assess the radon flux at the Mars soil surface. Diffusion of gas in Martian soil is governed by Knudsen diffusion. The radon Knudsen diffusion coefficient was estimated, depending on the soil moisture and relevant structural properties, leading to a radon diffusion length of the order of 20 m. The landed platform PALOMA-Radon instrument will consist of a

  3. Paloma-radon: atmospheric radon 222 as a geochemical probe for water in the martian subsoil

    International Nuclear Information System (INIS)

    Sabroux, J.Ch.; Michielsen, N.; Voisin, V.

    2003-01-01

    Radon exhalation from a porous soil is known to depend strongly on the soil moisture content: a minute amount of water, or water ice, in the pore space increases dramatically the possibility for radon to migrate far from its parent mineral. We propose to take advantage of this characteristic by using atmospheric radon 222 as a geochemical probe for water in the Martian soil, at least one order of magnitude deeper than the current Mars Odyssey neutron data. Strong thermal inversions during the Martian night will accumulate radon in the lowest atmospheric boundary layer, up to measurable levels despite the comparatively high environmental (cosmic and solar) background radiation and the assumed low uranium content of the upper crust of the planet. Preliminary studies and development of an instrument for the measurement of the Martian atmospheric alpha radioactivity is part of the CNES supported PALOMA experiment. Two test benches have been implemented, one of them allowing differential measurements of the diffusion of radon in the Martian soil simulant NASA JSC Mars-1, under relevant temperatures and pressures. The other, a 1 m3 radon-dedicated test bench, aims to characterize the instrument that will measure radon in the Mars environment (7 mb CO 2 ). Tests on several nuclear radiation detectors show that semiconductor alpha-particle detectors (PIPS) are the best option. In addition, the detection volume is left open in order to capitalize upon the long (ca. 4 m) alpha track at this low pressure. A stationary diffusion model was developed in order to assess the radon flux at the Mars soil surface. Diffusion of gas in Martian soil is governed by Knudsen diffusion. The radon Knudsen diffusion coefficient was estimated, depending on the soil moisture and relevant structural properties, leading to a radon diffusion length of the order of 20 m. The landed platform PALOMA-Radon instrument will consist of a set of alpha detectors connected to an electronic spectrometer, a

  4. Paloma-radon: atmospheric radon 222 as a geochemical probe for water in the martian subsoil

    Energy Technology Data Exchange (ETDEWEB)

    Sabroux, J.Ch.; Michielsen, N.; Voisin, V

    2003-07-01

    Radon exhalation from a porous soil is known to depend strongly on the soil moisture content: a minute amount of water, or water ice, in the pore space increases dramatically the possibility for radon to migrate far from its parent mineral. We propose to take advantage of this characteristic by using atmospheric radon 222 as a geochemical probe for water in the Martian soil, at least one order of magnitude deeper than the current Mars Odyssey neutron data. Strong thermal inversions during the Martian night will accumulate radon in the lowest atmospheric boundary layer, up to measurable levels despite the comparatively high environmental (cosmic and solar) background radiation and the assumed low uranium content of the upper crust of the planet. Preliminary studies and development of an instrument for the measurement of the Martian atmospheric alpha radioactivity is part of the CNES supported PALOMA experiment. Two test benches have been implemented, one of them allowing differential measurements of the diffusion of radon in the Martian soil simulant NASA JSC Mars-1, under relevant temperatures and pressures. The other, a 1 m3 radon-dedicated test bench, aims to characterize the instrument that will measure radon in the Mars environment (7 mb CO{sub 2}). Tests on several nuclear radiation detectors show that semiconductor alpha-particle detectors (PIPS) are the best option. In addition, the detection volume is left open in order to capitalize upon the long (ca. 4 m) alpha track at this low pressure. A stationary diffusion model was developed in order to assess the radon flux at the Mars soil surface. Diffusion of gas in Martian soil is governed by Knudsen diffusion. The radon Knudsen diffusion coefficient was estimated, depending on the soil moisture and relevant structural properties, leading to a radon diffusion length of the order of 20 m. The landed platform PALOMA-Radon instrument will consist of a set of alpha detectors connected to an electronic spectrometer

  5. Studies on indoor radon concentrations in Karimanagar district of Telangana State, India

    International Nuclear Information System (INIS)

    Srinivas Reddy, G.; Vinay Kumar Reddy, K.; Sreenivasa Reddy, B.; Ch Gopal Reddy, P.; Yadagiri Reddy, P.; Rama Reddy, K.

    2015-01-01

    Karimnagar district of Telangana state in India falls geologically under the Karimnagar Granulite Terrain (KGT) and, is well known for several types of granites. Studies revealed that the radiation levels are elevated with these granitic rocks. The indoor radon concentrations are estimated in about 80 dwellings, selected randomly in Karimnagar district, using LR-115 Type-II Solid State Nuclear Track Detectors based Twin Chamber Cup dosimeters for a period of one year on quarterly basis. The dose rates due to the radon concentrations are calculated. The seasonal variations of the indoor radon concentrations have been studied. Further, the dependency of indoor radon concentrations on different types of dwellings is also discussed in the present paper. (author)

  6. The ORNL Indoor Air Quality Study: Re-cap, Context, and Assessment on Radon

    Energy Technology Data Exchange (ETDEWEB)

    Tonn, Bruce Edward [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rose, Erin M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ternes, Mark P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-10-01

    As part of the retrospective evaluation of the U.S. Department of Energy s low-income Weatherization Assistance Program that was led by Oak Ridge National Laboratory (ORNL), an assessment of the impacts of weatherization on indoor air quality (IAQ) was conducted. This assessment included nearly 500 treatment and control homes across the country. Homes were monitored for carbon monoxide, radon, formaldehyde, temperature and humidity pre- and post-weatherization. This report focuses on the topic of radon and addresses issues not thoroughly discussed in the original IAQ report. The size, scope and rigor of the radon component of the IAQ study are compared to previous studies that assessed the impacts of weatherization on indoor radon levels. It is found that the ORNL study is by far the most extensive study conducted to date, though the ORNL results are consistent with the findings of the other studies. However, the study does have limitations related to its reliance on short-term measurements of radon and inability to attribute changes in radon levels in homes post-weatherization to specific weatherization measures individually or in combination.

  7. Modelling and experimental study of the behavior of radon and radon decay products in an enclosure. Application to houses; Modelisation et etude experimentale du comportement du radon et de ses descendants dans une enceinte confinee. Application a une habitation

    Energy Technology Data Exchange (ETDEWEB)

    Gouronnec, A M

    1995-02-03

    Since the eighties, more and more studies were performed about radon and its decay products in houses with one of the aim being the estimation of the dose received by their inhabitants. Then, the principal objective of this work is to describe the behaviour of radon and its decay products within a dwelling. In the first part to the report, a few definitions are given and data from literature give an idea of indoor radon and radon decay products activities and/or size distribution. Aspects of dosimetry are presented too. In the second part of the work, a mathematical model, called `PRADDO` of Physic of Radon and radon Decay products in Domestic environment is developed on the basis of the classical model written by Jacobi in 1972. On the one hand, it has to predict radon decay products activities in systems consisting in one or more enclosure(s), from radon activity and from ambient aerosol concentration and size distribution. On the other hand, one part of the model is assigned to study the influence of the entry model parameters variation on the calculated quantities. Then, in the third part of the work, two experimental studies are realised in order to compare measurements to modelization. The first experimentation is a laboratory work, made on the test bench ICARE from IPSN, and the second one consists in describing the basement of an occupied house from Brittany. In the two cases, the comparison between experiments and modelling shows a good agreement if particles are present in the air, but any conclusion is made when is no aerosol in the enclosure. (author). 158 refs., 81 figs., 42 tabs.

  8. Indoor radon and risk of lung cancer: an epidemiological study in Finland

    International Nuclear Information System (INIS)

    Ruosteenoja, E.

    1991-03-01

    The main aim of the present study was to establish whether high radon concentrations in dwellings in Finland had increased the risk of lung cancer. Previous studies had shown an association between the α-active radon daughters and elevated lung cancer risk among miners. Convincing evidence of the risk among the general population exposed to radon indoors was, however, lacking. A descriptive analysis was first conducted in an area in southern Finland with high indoor radon exposure. In 18 rural municipalities this analysis yielded no significant correlation between the average radon exposure and incidence of male lung cancer. A case-control study within a cohort of the same rural population was then designed. The data included 238 male cases of lung cancer diagnosed in 1980-85 and 434 controls (390 smokers and 44 nonsmokers) from the male population. Radon exposure was measured, when possible, in all the dwellings occupied by a case or control in 1950-1975. Measurements were available for the total 25-year period, or for a proportion of it, for 164 cases and 334 controls; for the rest only estimates were available. In spite of the fact that the controls were mainly selected among smokers, the amount smoked still appeared to be the most important lung cancer risk factor in the data, the risk increasing linearly with the quantity of cigarettes smoked in a lifetime. The risk of lung cancer was not associated with the radon exposure level when the whole data were studied. In heavy smokers, however, a positive though not significant, effect on the risk from radon exposure was found. In the range of uncertainty the findings do not conflict with most of those observed among miners or the general population so far. (orig.)

  9. A comparison study between radon concentration in schools and other workplaces

    International Nuclear Information System (INIS)

    Clouvas, A.; Xanthos, S.

    2012-01-01

    The Nuclear Technology Laboratory of the Aristotle Univ. of Thessaloniki has since 1999 an open research project of indoor radon measurements in Greek workplaces. Since now 1380 measurements in 690 workplaces have been performed. Most (75 %) of the workplaces were offices in schools. The remaining 25 % were offices, mainly in public buildings. In the present study, a possible correlation between radon concentration in schools and other workplaces is investigated and discussed. (authors)

  10. Radon in the workplace: Implications of studies of post-remediation monitoring

    International Nuclear Information System (INIS)

    Denman, A. R.; Parkinson, S.; Johnstone, M.; Crockett, R. G. M.; Phillips, P. S.

    2004-01-01

    Radon gas has been shown to cause an increased incidence of lung cancer. In affected areas, levels in the overground workplace can be sufficiently high to be a health risk and remediation is required. In the UK, the workplace Action Level is 400 Bq m -3 . The variation of radon levels in the workplace was studied both before and after remediation. In most rooms, remediation resulted in a greater reduction at night than during the working day. The dose reduction, and therefore the health benefit, to workers is less than that predicted by the drop in radon averaged over 24 h. In order to obtain a health benefit to 75% of workers in our series, the 24 h average radon level in each room must be reduced to -3 . It is recommended that UK Regulatory Agencies adopt a post-remediation workplace Action Level of 225 Bq m -3 . (authors)

  11. Study on absolute humidity influence of NRL-1 measuring apparatus for radon

    International Nuclear Information System (INIS)

    Shan Jian; Xiao Detao; Zhao Guizhi; Zhou Qingzhi; Liu Yan; Qiu Shoukang; Meng Yecheng; Xiong Xinming; Liu Xiaosong; Ma Wenrong

    2014-01-01

    The absolute humidity and temperature's effects on the NRL-1 measuring apparatus for radon were studied in this paper. By controlling the radon activity concentration of the radon laboratory in University of South China and improving the temperature and humidity adjust strategy, different correction factor values under different absolute humidities were obtained. Moreover, a correction curve between 1.90 and 14.91 g/m"3 was also attained. The results show that in the case of absolute humidity, when it is less than 2.4 g/m"3, collection efficiency of the NRL-1 measuring apparatus for radon tends to be constant, and the correction factor of the absolute humidity closes to 1. However, the correction factor increases nonlinearly along with the absolute humidity. (authors)

  12. Study of radon progeny distribution and radiation dose rate in the atmosphere

    International Nuclear Information System (INIS)

    Fujinami, Naoto

    2009-01-01

    The absorbed dose rate in air of airborne gamma-ray and the concentration of radon progeny in surface air have been observed continuously in Maizuru, Japan. When data observed on fine days were plotted, with dose rate as ordinate and contraction as abscissa, these points traced with a lapse of time illustrated an anticlockwise looping for each day. This result suggests that the variation of absorbed dose rate lags behind that of concentration of radon progeny; this is due to the delay time incurred as the concentration level gradually varies from ground surface to upper air. Radon progeny concentrations in precipitation and in surface air have been observed there in order to study the relationship between the two concentrations and the influence of precipitation patterns on the concentration in precipitation. Results obtained from analysis of the observed data suggest that radon progeny in precipitation originate mainly from scavenging within the cloud (rainout) and not from that below the cloud (washout). (author)

  13. Study on radon concentration monitoring using activated charcoal canisters in high humidity environments

    International Nuclear Information System (INIS)

    Wang Yuexing; Wang Haijun; Yang Yifang; Qin Sichang; Wang Zhentao; Zhang Zhenjiang

    2009-01-01

    The effects of humidity on the sensitivity using activated charcoal canisters for measuring radon concentrations in high humidity environments were studied. Every canister filled with 80 g of activated charcoal, and they were exposed to 48 h or 72 h in the relative humidity of 68%, 80%, 88% and 96% (28 degree C), respectively. The amount of radon absorbed in the canisters was determined by counting the gamma rays from 214 Pb and 214 Bi (radon progeny). The results showed that counts decreased with the increase of relative humidity. There was a negative linear relationship between count and humidity. In the relative humidity range of 68%-96%, the sensitivity of radon absorption decreased about 2.4% for every 1% (degree)rise in humidity. The results also showed that the exposure time of the activated charcoal canisters should be less than 3 days. (authors)

  14. Intercomparison of passive radon-detectors under field conditions in epidemiological studies.

    Science.gov (United States)

    Kreienbrock, L; Poffijn, A; Tirmarche, M; Feider, M; Kies, A; Darby, S C

    1999-05-01

    The Ardennes and Eifel region is a geologically distinct area covering parts of Germany, Belgium, France, and Luxembourg where enhanced concentrations of radon occur in some houses and other buildings. An international case-control study is being conducted to examine the role of radon in the etiology of lung cancer in this area. The radon detectors used are issued by different laboratories involving a variety of detector types and processes. A series of intercomparisons in houses was therefore conducted under similar conditions of exposure in the field. In most situations the different detectors gave similar results. Nevertheless, in some situations open and closed detectors yielded different results. Therefore, estimates of radon exposure have to be adjusted if results are to be pooled.

  15. Potential study of bed filtration characteristics in impressed boreholes by radon tracer technique

    International Nuclear Information System (INIS)

    Litvinov, A.A.; Pinkenzon, D.B.; Makarov, M.S.; Vinarskij, M.S.

    1977-01-01

    Potential study of bed filtration characteristics in impressed boreholes by radon tracer method is shown. Effects recorded by radon tracer result from gamma radiation of short-living radon decay daughter products. During filtration of tracer through punched holes, cement stone, and rocks the products are deposited and cause a local effect for 2-3 hours. There is a shortage of short-living products in filtrated radon liquid and for some time (which is necessary for production of notable quantity of new decay products) it is practically not a gamma emitter. It is shown that the feature of effect formation governs the technique for well logging as well as interpretation of the results obtained

  16. Comparative study of different types of granular activated carbon in removing medium level radon from water

    International Nuclear Information System (INIS)

    Alabdula'aly, A.I.; Maghrawy, H.B.

    2011-01-01

    Granular activated carbon (GAC) has proven its effectiveness in removing radon from water supplies. Laboratory and pilot plant studies were carried out using three different types of activated carbons (F-300, F-400, and HD-4000) to remove radon from water supply. From the experimental kinetic study, the data indicated that at least 6 h are needed to attain equilibrium between radon activity adsorbed onto carbon and its concentration in the aqueous phase. Also, it showed that HD-4000 has higher capacity for removing radon than the other two investigated carbons F-300 and F-400. The adsorption isotherms were satisfactorily explained by Freundlich equation. In the pilot plant study, the performance of the three activated carbons in removing radon at medium concentration (∼111 Bq dm -3 ) was evaluated over 60 days of continuous water flow. Four empty-bed contact times (EBCTs) corresponding to four bed depths were continuously monitored and the corresponding steady state adsorption-decay constant values were calculated and the efficiency of each carbon was used to provide a facet for comparison. The γ-radiation exposure rate distribution throughout each GAC bed was measured and compared. This study, despite paucity of literature in this field, is useful for designing a GAC adsorption system for the removal of medium level radon concentration from water supplies. (author)

  17. Studies on radon concentration in underground water samples in and around Kabini river basin

    International Nuclear Information System (INIS)

    Yashaswini, T.; Ningappa, C.; Niranjan, R.S.; Sannappa, J.

    2017-01-01

    Radon is a radioactive inert gas, a decay product of radium, causes environmental health problems like lung cancer. Radium present in the earth crest continuously releases radon into underground water. From the point view of health, the study of radon concentration level in underground water base line data is important. In the present study, radon concentration in underground water have been measured in 40 underground water samples collected in and around Kabini River of Karnataka State by using Emanometry technique. The radon concentration in the study area varies from 21.2 to 168.2Bq.l -1 with a geometrical mean value of 73.3 Bq.l -1 . The physicochemical parameters of water such as chloride, Fluoride, nitrite, sulphate, TDS are measured in the same samples in order to know about the impact of these parameters on radon concentration and their health risks to the general public. The experimental techniques and results obtained are discussed in the presentation. (author)

  18. Study of temporal variation of radon concentrations in public drinking water supplies

    International Nuclear Information System (INIS)

    York, E.L.

    1995-01-01

    The Environmental Protection Agency (EPA) has proposed a Maximum Contaminant Level (MCL) for radon-222 in public drinking water supplies of 300 pCi/L. Proposed monitoring requirements include collecting quarterly grab samples for the first year, then annual samples for the remainder of the compliance cycle provided first year quarterly samples average below the MCL. The focus of this research was to study the temporal variation of groundwater radon concentrations to investigate how reliably one can predict an annual average radon concentration based on the results of grab samples. Using a open-quotes slow-flowclose quotes collection method and liquid scintillation analysis, biweekly water samples were taken from ten public water supply wells in North Carolina (6 month - 11 month sampling periods). Based on study results, temporal variations exist in groundwater radon concentrations. Statistical analysis performed on the data indicates that grab samples taken from each of the ten wells during the study period would exhibit groundwater radon concentrations within 30% of their average radon concentration

  19. A radon (thoron) daughter personal alpha-dosimeter of the passive type using a diffused-junction detector and an electrostatic collector

    International Nuclear Information System (INIS)

    Bigu, J.; Frattini, A.

    1984-05-01

    A solid-state alpha-dosimeter has been designed and found to be suitable for personal and environmental radon-thoron daughter monitoring. The dosimeter basically consists of an electrostatic collector and an alpha-particle counting system with spectroscopy capabilities. The sensitive volume (∼20 cm 3 ) of the electrostatic collector consists of a cylindrically-shaped metal wire screen and a diffused-junction silicon alpha-detector covered with a thin aluminized mylar sheet. A DC voltage (∼450 V) is applied between the wire screen and the mylar sheet, the latter held at negative potential relative to the metal screen. Data can be retrieved during or after sampling by means of a micro-computer (Epson HX20) via a RS-232 communcation interface unit. The dosimeter has been calibrated in a large (26 m 3 ) radon/thoron test facility. A linear relationship was found between radon gas concentration and radon daughter Working Level, and the dosimeter's alpha-count. The dosimeter is mounted on top of an ordinary miner's cap lamp battery and is ideally suited for personal monitoring in underground uranium mines and other working areas. The dosimeter presented here is a considerably improved version of an earlier prototype

  20. Some characteristics of the Atomic Energy Organization of Iran (AEOI) passive radon diffusion dosimeter for indoor exposure determination of public in Iran

    International Nuclear Information System (INIS)

    Sohrabi, M.; Solaymanian, A.R.

    1989-01-01

    A Passive Radon diffusion dosimeter (PRDD) was developed at the Radiation Protection Department of the Atomic Energy Organization of Iran (AEOI) for large scale radon level measurements in Iran. It consists of a plastic cup with a polycarbonate alpha detector in the middle, a plastic top cover with an opening holding a fiberglass filter and a hard aluminium mesh for protection and support. A new design of our multi-chamber system was used for multiple foil etching. The effects of pre-etching and ECE times, chamber volume, filter diameter and foil position inside the chamber were investigated. The optimized geometries include 9.5 cm height, 269 cm 3 volume and 2-3 cm filter diameter with the polycarbonate foil mounted in the middle. A sensitivity of 0.05+-0.007 tracks cm -2 /Bq.m -3 day or 1.96+-0.28 tracks cm -2 /pCi.1 -1 day was obtained at optimized conditions. The characteristics of the dosimeter as well as some preliminary results of indoor radon level measurements for determination of public exposure in 250 houses in different cities of Iran including Tehran, Ramsar, Babolsar and Gonabad are presented. The highest radon levels were found in high natural areas of Ramsar

  1. Experimental study of the combined effects of inhalation of radon daughter products and tobacco smoke

    International Nuclear Information System (INIS)

    Chameaud, J.; Perraud, R.; Chretien, J.; Masse, R.; Lafuma, J.

    1979-01-01

    For 10 years, over 500 lung cancers have been induced in rats by inhalations of radon daughter products at various concentrations and cumulated doses. Considering several points and the dose-effect relationship especially, such cancers can be compared with human cancers. This type of experiments, fully mastered, has made it possible to undertake under good conditions the study of the co-carcinogenic effect of various inhaled pollutants such as tobacco smoke. In a first experiment, 100 rats were exposed to a 4000WLM cumulated dose of radon daughter products, knowing that this level induces some 30% of lung cancers. 50 animals were then administered tobacco smoke by inhalation in a fume box during 5 months (350 h.) In the group inhaling radon only, 17 cancers appeared; in the radon -tobacco group 32 cancers bigger and more invasive were observed. Under the same conditions, tobacco smoke was inhaled by rats previously exposed to lower doses of radon daughter products (2 groups of 30 rats, 500 and 100 WLM respectively). Again, the number of cancers observed was higher that the number of cancers expected if the rats had inhaled radon only. This co-carcinogenic and potentiating action of tobacco was clearly demonstrated. Further experiments are considered in order to determine the processes involved

  2. A comparative study of indoor radon concentrations between dwellings and schools

    International Nuclear Information System (INIS)

    Kapdan, E.; Altinsoy, N.

    2012-01-01

    The aim of this study is to determine the relationship of radon concentrations between dwellings and the schools located in the same regions and to obtain related indoor average radon concentration dwelling–school correction factor for similar locations. The research has been carried out by determining indoor radon concentrations at schools and dwellings located at the same districts in the selected two separate research fields called The Former Adapazari region and The New Adapazari region in the city of Adapazari using a total of 81 Cr-39 passive radon detectors for 75 days. The average radon concentrations have been determined for the dwellings and the schools in 15 districts of the Former Adapazari region as 59.9 Bq m −3 and 57.1 Bq m −3 , respectively. The results in 4 districts of the New Adapazari region were 63.5 Bq m −3 for the dwellings and 61.0 Bq m −3 for the schools. Moreover, the annual effective doses were calculated as 1.33 mSv/y and 1.41 mSv/y for the dwellings of Former Adapazari and New Adapazari, respectively. It was seen that the doses received in the dwellings are about four times the doses received in the schools. The indoor radon concentration dwelling–school correction factor was found to be 1.04±0.01 for the research area.

  3. A Laboratory for studying radon mitigation methods in high-rise office buildings in Hong Kong

    International Nuclear Information System (INIS)

    Leung, J.K.C.; Hung, L.C.; Tso, M.Y.W.

    1996-01-01

    A territory-wide survey of indoor radon level in 1993 showed that 17% of offices Hong Kong have radon concentrations above 200 Bq m -3 compared with 4% for dwellings. Consequently, the Radioisotope Unit Radon Analysis Laboratory (RURAL) is being built for studying radon mitigation methods applicable to high-rise office buildings. The laboratory consists of three rooms; the main exposure room is built of concrete and is surrounded by the buffer room; and all controls and operations are done inside the control room. The exposure room can, with the aid of the buffer room, simulate any environmental conditions that can be faced by a real building. The pressure, temperature and humidity can be adjusted to any meteorological conditions that can be found in Hong Kong. Pressure differential and temperature differential can be adjusted to simulate the arrival of fronts, troughs or typhoons. Aerosol concentration and distribution inside the exposure room are controllable as well as the ventilation conditions. Various mitigation methods will be tested under different conditions. Passive methods include application of radon barriers to building structures and active methods include the use of air cleaners; techniques to increase radon daughters plateout or reduce their attachment to aerosols; and various modifications to the ventilation systems. Mitigation techniques involving modifications to the building strictures and building services will also be developed with the help of the RURAL. (author)

  4. Development of a radon chamber and measurement of the radon solubility in tissues; Entwicklung einer Radonkammer und Messung der Radonloeslichkeit in Gewebe

    Energy Technology Data Exchange (ETDEWEB)

    Maier, Andreas

    2015-04-22

    Every year thousands of patients with inflammatory diseases of the musculoskeletal system undergo radon therapy, but the molecular mechanism and the risk of this therapy are not understood. To study the effects of radon exposure in vitro and in vivo we constructed a radon exposure chamber in the framework of the GREWIS project. With this device we are able to expose samples under controlled and reproducible conditions including the radon galleries in Austria and Germany. Adjustable parameters are radon activity-concentration, temperature, humidity and exposure time. These parameters are permanently monitored and controlled. During experiments with cell cultures it is also possible to adjust the CO{sub 2}-concentration. In addition, experiments with mice can be performed with this setup. To measure the radon kinetics in different types of tissue we exposed tissue samples like fat or muscle and mice in the radonchamber. Afterwards we measured the -spectra of the short living radon decay products lead-214 and bismuth-214 in the exposed samples with a HPGe-Detector. We recorded the spectra at different time points after exposure and calculated the initial amount of radon at the end of the exposure period in the sample and investigated the diffusion of the radon out of it. We compared the results from different types of tissue but also activated coal. In an activated coal sample the radon is bound to it via Van-der-Waals-force and the decay spectra are governed by the life time of the bound radon (3,8 days). In contrast in the biological samples the primary radon diffuses out of the samples in less than 20 minutes and the spectra follow the kinetics of the decay of the daughter products. These measurements where performed for the first time under therapy conditions like in radon galleries and also with higher radon concentration. In our experiments we could see an enhanced accumulation of radon and its decay products in fatty tissue compared to muscle tissue. Also in

  5. Attachment of radon progeny to cigarette-smoke aerosols

    International Nuclear Information System (INIS)

    Biermann, A.H.; Sawyer, S.R.

    1995-05-01

    The daughter products of radon gas are now recognized as a significant contributor to radiation exposure to the general public. It is also suspected that a synergistic effect exists with the combination cigarette smoking and radon exposure. We have conducted an experimental investigation to determine the physical nature of radon progeny interactions with cigarette smoke aerosols. The size distributions of the aerosols are characterized and attachment rates of radon progeny to cigarette-smoke aerosols are determined. Both the mainstream and sidestream portions of the smoke aerosol are investigated. Unattached radon progeny are very mobile and, in the presence of aerosols, readily attach to the particle surfaces. In this study, an aerosol chamber is used to contain the radon gas, progeny and aerosol mixture while allowing the attachment process to occur. The rate of attachment is dependent on the size distribution, or diffusion coefficient, of the radon progeny as well as the aerosol size distribution. The size distribution of the radon daughter products is monitored using a graded-screen diffusion battery. The diffusion battery also enables separation of the unattached radon progeny from those attached to the aerosol particles. Analysis of the radon decay products is accomplished using alpha spectrometry. The aerosols of interest are size fractionated with the aid of a differential mobility analyzer and cascade impactor. The measured attachment rates of progeny to the cigarette smoke are compared to those found in similar experiments using an ambient aerosol. The lowest attachment coefficients observed, ∼10 -6 cm 3 /s, occurred for the ambient aerosol. The sidestream and mainstream smoke aerosols exhibited higher attachment rates in that order. The results compared favorably with theories describing the coagulation process of aerosols

  6. Studies on the diffusional and electrical transport of the daughter aerosols of radon and thoron in moving gases

    International Nuclear Information System (INIS)

    Mayya, Y.S.; Sahni, D.C.

    1994-01-01

    This report presents a detailed theoretical study of the transport characteristics of the daughter products of radon and thoron gases in channel flow devices. Specific aspects examined include: (i) development of the Green's function of the convective-diffusion operator and its boundary layer forms with and without axial diffusion, (ii) transport probabilities of recoil atoms (RaB) emitted into stagnant and moving gases, due to alpha decays of the parent atoms (RaA) deposited on surfaces, (iii) a comprehensive theory of double filter systems and (iv) microscopic theory of particle transport in moving fluids based on the Fokker-Planck equation. Both uniform and parabolic velocity profiles are considered. Various applications of the solutions in interpreting the measured data are presented. Chief among them is the application of the advanced theory of double-filter systems employed in Trombay studies for the measurements of thoron in the exhaled breath of thorium workers. (author). 130 refs., 4 figs

  7. Measurements of radon in soil gas

    International Nuclear Information System (INIS)

    Paschuk, Sergei A.; Correa, Janine Nicolosi; Schelin, Hugo R.; Barbosa, Laercio; Sadula, Tatyana; Matsuzaki, Cristiana A.

    2009-01-01

    Full text: After the decades of systematic and numerous studies performed at different countries of the World, it has been concluded that radon as well as its progeny is the main cause of lung cancer. It is well known that more than 50% of the effective annual radiation dose received by a human being is related to the radon and its progenies. Among the principle mechanisms that bring the radon inside the dwelling is the soil exhalation as well as exhalation and release from the water. Radon concentration in the soil and its transport (emanation, diffusion, advection and adsorption) to the surface depends on different physical, geological and ambient parameters such as the geology of the area, geochemical composition of the soil, its porosity and permeability, grain size, soil humidity, bottom sediments and inputs from streams, temperature, atmospheric pressure, etc. Since the main part of indoor radon originates in the soil, the measurements of radon concentration in soil gas have to be considered as an important tool and indicator of probable high levels of radon inside the dwellings. Present work describes the radon in soil gas measurements performed during the last two years in cooperation between the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR), the Nuclear Technology Development Center (CDTN) and the Institute of Radiation Protection and Dosimetry (IRD) from the Brazilian Nuclear Energy Commission (CNEN). Following previously concluded measurements of radon concentration in dwellings and the measurements of 222 Rn activity in drinking water collected at artesian bores of Curitiba urban area, present step of activities has been dedicated to measurements of radon concentration in soil gas. Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specially developed for such measurements Soil Gas Probe through the air pump and filter system. The equipment was adjusted with air flow of 0

  8. Some basic facts about radioactive radon

    International Nuclear Information System (INIS)

    Duval, J.S.; Tanner, A.B.

    1990-01-01

    This article presents some basic facts about 222 Rn. These facts include: half-life; diffusion patterns; how radon enters a house; health risks; and means of definition and estimation of radon hazard potential

  9. Factors influencing radon attenuation by tailing covers

    International Nuclear Information System (INIS)

    Silker, W.B.; Rogers, V.C.

    1981-07-01

    The US NRC, in its Generic Environmental Impact Statement on uranium milling has specified that the radon flux escaping a uranium mill tailings pile will be reduced to pCi/m 2 s by application of covering layers of soils and clays. These covers present a radon diffusion barrier, which sufficiently increases the time required for radon passage from the tailings to the atmosphere to allow for decay of 222 Rn within the cover. The depth of cover necessary to reduce the escaping radon flux to the prescribed level is to be determined by calculation, and requires precise knowledge of the radon diffusion coefficient in the covering media. A Radon Attenuation Test Facility was developed to determine rates of radon diffusion through candidate cover materials. This paper describes this facility and its application for determining the influence of physical properties of the soil column on the radon diffusion coefficient

  10. Comparative study of radon concentration in selected modern and traditional building at Kenyatta University

    International Nuclear Information System (INIS)

    Chege, W.M.; Rathore, I.V.S.; Chhabra, S.C.; Mustapha, A.O.

    2010-01-01

    Radon is leading source of radiation exposure to the public and increases risk of cancer (UNSCEAR, 2000). There is general lack of data on indoor radon in Kenya especially on building design-traditional versus modern. In rural Kenya traditional mud huts coexist with modern stone building. Indoor radon found to vary widely in Kenya: Mustapha et al (2002): 5-1200 Bqm3, Maina et al (2004): 5-704 Bqm3. None of previous works indicates radon variation with building design. The aim of the current study is to compare radon concentrations in coexisting stone buildings and mud huts. Such data would be useful in formulation of policies regarding housing, as part of radon data base in Kenya Experimental Techniques Characteristic of selected buildings: Traditional Huts: Single roomed, Wall made of wood and plastered using mud, bare floor and no ceiling, grass-thatched or mud plastered, doors and windows remained open during the sampling period. Modern Buildings: (Classes used to represent modern building). Those made of natural stone, wooden floor, ceiling, doors and windows remained shut during the sampling period. Measurement of Radon Concentration Radon sampling was done using Charcoal canisters (EPA type). They were activated, and then exposed simultaneously at sampling sites for 48 hours. Analysis and data acquisition was done using NaI(Tl) gamma-ray spectrometer. Radon concentration was calculated based on gamma rays emitted by 214Pb (295 and 352 keV) and 214Bi (609 keV). 13 Results and Discussion Radon levels were higher in classrooms and significantly high in huts. Mean (Bqm-3 ) Minimum (Bqm-3 ) Maximum (Bqm-3 ). Traditional huts had 170.3 15.6 30.2 315.4 while modern buildings had 193 ±19.3 115.76 257.2. There were higher levels in classroom despite lower levels of 226Ra (50.18 Bqkg-1) in natural stone. Possible source of high concentrations: - radon seeping in through floor boards building up over time as building more closed up - Radon concentration was more varied

  11. A study of indoor radon in greenhouses in Mexico City, Mexico

    International Nuclear Information System (INIS)

    Guillermo Espinosa; Allan Chavarria; Jose-Ignacio Golzarri

    2013-01-01

    Enclosed spaces in contact with soil, the main source of radon, like greenhouses have potentially high radon ( 222 Rn) concentrations. Greenhouses are frequented by visitors and also are workplaces. The study of radon concentrations in greenhouses is, thus, a relevant concern for public health and environmental radiation authorities. For this study, the radon concentrations in 12 greenhouses in different locations within Mexico City were measured using nuclear track methodology. The detectors used for the study consisted of the well-known closed-end cup device, with CR-39 Lantrack R as detector material. The measurements were carried out over a period of one year, divided into four three-month sub-periods. The lowest and highest annual mean radon concentrations found in individual greenhouses were 17.0 and 45.1 Bq/m 3 , respectively. The annual mean averaged over all 12 greenhouses was 27.3 Bq/m 3 . No significant seasonal variation was observed. Using the highest annual mean radon concentration found in an individual greenhouse, and an equilibrium factor of 0.4, the effective dose from 222 Rn and its progenies was calculated to be 339.9 nSv/h. This corresponds to an annual dose rate of 679.8 μSv/y (0.057 WLM/y) for a worker spending 4 h a day, 5 days a week, 50 weeks a year, inside the greenhouse. For a visitor spending 12 h a year inside the greenhouse the annual dose is 2.469 μSv/y. The study of indoor radon concentrations in closed buildings such as greenhouses, which are both workplaces and open to visitors, is an important public health consideration. (author)

  12. An experimental setup for measuring generation and transport of radon in building materials

    NARCIS (Netherlands)

    van der Pal, M.; Hendriks, N.A.; de Meijer, R.J.; van der Graaf, E.R.; de Wit, M.H.

    2001-01-01

    This study describes an approach for measuring and modelling diffusive and advective transport of radon through building materials. The goal of these measurements and model calculations is to improve our understanding concerning the factors influencing the transport of radon through building

  13. Scope of radon monitoring for earthquake-studies in India

    International Nuclear Information System (INIS)

    Virk, H.S.

    1994-01-01

    In India, there is scope for investigating and exploiting radon as a precursor for earthquakes and for exploration of hydrocarbon deposits. This report mainly deals with the investigations carried out in Kangra and Chamba valleys of Himachal Pradesh under Himalayan Seismicity Project of Department of Science and Technology, Govt. of India. 20 refs., 4 figs., 1 tab

  14. Radon-222 Study in Ceramics and Indoor Air

    International Nuclear Information System (INIS)

    Moussa, N.L.A.A.

    2011-01-01

    A total 50 samples of 13 different ceramic tiles companies collected from the Egyptian market for the measurements of radon exhalation rate. Three homes include twenty rooms were selected. The period of the survey was in range 2-3 months for homes for each season while it was about 15 days for ceramic tiles. The radon exhalation rate of ceramic tiles (clay and glaze) and indoor radon activity concentration were measured by alpha tracks technique. The average radon exhalation rate in three homes was observed to be in the range 2.2-5.2 mBq.m -2 .h -1 . The average of Ra-226 activity for all ceramic tiles either the floor or wall tile is in the range 16-64 Bq.kg -1 . The porosity of ceramic tiles is found in the range 0.19-0.29. The effective dose in all rooms is found in the range 0.9- 1.3 mSv.y -1 .

  15. Study and development of microporous organic compounds for radon adsorption and his application in particle physics

    International Nuclear Information System (INIS)

    Noel, Raymond

    2015-01-01

    The neutrino is one of the twelve elementary particles from the standard model. It is characterize by a neutral electrical charge and an extremely low mass. Many experiments have been set up in order to study the properties of neutrino. Despite scientific breakthrough, the nature of this particle is still unknown up to now. The NEMO collaboration is studying the neutrinoless double beta decay, a very rare radioactive process, to find out the nature of neutrino and to know if the neutrino is equivalent to the antineutrino. Today, the NEMO collaboration is building a new detector called SuperNEMO. The gas inside the detector need to have a concentration in radon below 100 μBq/m"3, to minimize the radioactive background. The purification of this gas is achieved from the adsorption of radon by microporous material. In this work, we have developed in CPPM a bench test to measure the radon adsorption by various materials, in order to propose an adsorption model, and to reach the purity condition needed for SuperNEMO. Along with the study on adsorbents available and to better understand the radon adsorption, we synthesized and studied at CINaM star-shape poly-aromatic hydrocarbons and branched or dendritic aromatic polymers, incorporating sulfur, to adsorb radon [fr

  16. A study of the influence of a gravel subslab layer on radon entry rate using two basement structures

    International Nuclear Information System (INIS)

    Robinson, A.L.; Sextro, R.G.; Fisk, W.J.; Garbesi, K.; Wooley, J.; Wollenberg, H.A.

    1993-01-01

    In buildings with elevated radon concentrations, the dominant transport mechanism of radon is advective flow of soil gas into the building substructure. However, the building-soil system is often complex, making detailed studies of the radon source term difficult. In order to examine radon entry into buildings, the authors have constructed two room-size, precisely-fabricated basement structures at a site with relatively homogeneous, moderately permeable soil. The basements are identical except that one lies directly on native soil whereas the other lies on a high permeability aggregate layer. The soil pressure field and radon entry rate have been measured for different basement pressures and environmental conditions. The subslab gravel layer greatly enhances the advective entry of radon into the structure; when the structures are depressurized, the radon entry rate into the structure with the subslab gravel layer is more than a factor of 3 times the radon entry rate into the other structure for the same depressurization. The gravel subslab layer also spreads the pressure field around the structure, extending the field of influence of the structure and the region from which it draws radon

  17. A study of indoor radon, thoron and their exhalation rates in the environment of Fazilka district, Punjab, India

    Science.gov (United States)

    Narang, Saurabh; Kumar, Deepak; Sharma, Dinesh Kumar; Kumar, Ajay

    2018-02-01

    Over the last few decades, the study of radioactive radon gas has gained huge momentum due to its possible role in health related hazards. In the present work, pin-hole twin chamber single entrance dosimeters have been used for track measurements of radon and thoron. The annual average radon concentration varies from 50.3 to 204 Bq/m3 at all locations. Almost all the values are below the safe range provided by ICRP. Radon concentration is found to be higher in winter as compared to other seasons. Variation of radon with quality of dwellings is also discussed. The values of annual effective dose due to radon and thoron are also well within the range provided by ICRP and WHO. Radon and thoron exhalation rates are measured using SMART RnDuo monitor. The radon mass exhalation rates ranged from 11 to 71 mBq/kg/h while the thoron surface values ranged from 36 to 2048 Bq/m2/h. All the values are on the lower side. A weak correlation is found between radon and thoron concentrations and their exhalation rates. When compared with the values of other parts of northern India, the values of present investigation are on higher side.

  18. A study of the influence of a gravel subslab layer on radon entry rate using two basement structures

    International Nuclear Information System (INIS)

    Robinson, A.L.; Sextro, R.G.; Fisk, W.J.; Garbesi, K.; Wooley, J.; Wollenberg, H.A.

    1993-01-01

    In buildings with elevated radon concentrations, the dominant transport mechanism of radon is advective flow of soil gas into the building substructure. However, the building-soil system is often complex, making detailed studies of the radon source term difficult. In order-to examine radon entry into buildings, we have constructed two room-size, precisely-fabricated basement structures at a site with relatively homogeneous, moderately permeable soil. The basements are identical except that one lies directly on native soil whereas the other lies on a high permeability aggregate layer. The soil pressure field and radon entry rate have been measured for different basement pressures and environmental conditions. The subslab gravel layer greatly enhances the advective entry of radon into the structure; when the structures are depressurized, the radon entry rate into the structure with the subslab gravel layer is more than a factor of 3 times the radon entry rate into the other structure for the same depressurization. The gravel subslab layer also spreads the pressure field around the structure, extending the field of influence of the structure and the region from which it draws radon. (orig.). (7 refs., 3 figs.)

  19. ERRICCA radon model intercomparison exercise

    DEFF Research Database (Denmark)

    Andersen, C.E.; Albarracín, D.; Csige, I.

    1999-01-01

    -state diffusive radon profiles in dry and wet soils, (2) steady-state entry of soil gas and radon into a house, (3) time-dependent radon exhalation from abuilding-material sample. These cases cover features such as: soil heterogeneity, anisotropy, 3D-effects, time dependency, combined advective and diffusive......, still remain. All in all, it seems that the exercise has served its purpose and stimulated improvements relating to the quality of numerical modelling of radon transport. To maintain a high quality of modelling, it is recommendedthat additional exercises are carried out....

  20. Concentration variation of radon in the room

    International Nuclear Information System (INIS)

    Komaruzaman Mohd Noor; Haziman Hassan; Rosli Mahat; Yusof Md Amin

    1995-01-01

    The study was carried out to determine the variation of radon concentration in the room. Radon detector used was solid nuclear tracks detector (SSNTD) LR-115. From this result, suitable points to make radon measurement was determined

  1. Diffusion

    International Nuclear Information System (INIS)

    Kubaschewski, O.

    1983-01-01

    The diffusion rate values of titanium, its compounds and alloys are summarized and tabulated. The individual chemical diffusion coefficients and self-diffusion coefficients of certain isotopes are given. Experimental methods are listed which were used for the determination of diffusion coefficients. Some values have been taken over from other studies. Also given are graphs showing the temperature dependences of diffusion and changes in the diffusion coefficient with concentration changes

  2. A modeling study of the effect of depth of burial of depleted uranium and thorium on radon gas flux at a dry desert alluvial soil radioactive waste management site (RWMS)

    International Nuclear Information System (INIS)

    Lindstrom, F.T.; Cawlfield, D.E.; Emer, D.F.; Shott, G.J.

    1993-08-01

    An integral part of designing low-level waste (LLW) disposal pits and their associated closure covers in very dry desert alluvium is the use of a radon gas transport and fate model. Radon-222 has the potential to be a real heath hazard. The production of radon-222 results from the radioactive decay (a particle emission) of radium-226 in the uranium-235 and 238 Bateman chains. It is also produced in the thorium-230 series. Both long lived radionuclides have been proposed for disposal in the shallow land burial pits in Area 5 RWMS compound of Nevada Test Site (NTS). The constructed physics based model includes diffusion and barometric pressure-induced advection of an M-chain of radionuclides. The usual Bateman decay mechanics are included for each radionuclide. Both linear reversible and linear irreversible first order sorption kinetics are assumed for each radionuclide. This report presents the details of using the noble gas transport model, CASCADR9, in an engineering design study mode. Given data on the low-level waste stream, which constitutes the ultimate source of radon-222 in the RWMS, CASCADR9 is used to generate the surface flux (pCi/cm 2 -sec) of radon-222 under the realistic atmospheric and alluvial soil conditions found in the RWMS at Area 5, of the NTS. Specifically, this study examines the surface flux of radon-222 as a function of the depth of burial below the land surface

  3. Experimental and Monte Carlo simulation studies of open cylindrical radon monitoring device using CR-39 detector

    Energy Technology Data Exchange (ETDEWEB)

    Rehman, Fazal-ur- E-mail: fazalr@kfupm.edu.sa; Jamil, K.; Zakaullah, M.; Abu-Jarad, F.; Mujahid, S.A

    2003-07-01

    There are several methods of measuring radon concentrations but nuclear track detector cylindrical dosimeters are widely employed. In this investigation, the consequence of effective volumes of the dosimeters on the registration of alpha tracks in a CR-39 detector was studied. In a series of experiments an optimum radius for a CR-39-based open cylindrical radon dosimeter was found to be about 3 cm. Monte Carlo simulation techniques hav been employed to verify the experimental results. In this context, a computer code Monte Carlo simulation dosimetry (MOCSID) was developed. Monte Carlo simulation experiments gave the optimum radius of the dosimeters as 3.0 cm. The experimental results are in good agreement with those obtained by Monte Carlo design calculations. In addition to this, plate-out effects of radon progeny were also studied. It was observed that the contribution of radon progeny ({sup 218}Po and {sup 214}Po) plated-out on the wall of the dosimeters increases with an increase of dosimeter radii and then decrease to 0 at a radius of about 3 cm if a point detector has been installed at the center of the dosimeter base. In the code MOCSID different types of random number generators were employed. The results of this research are very useful for designing an optimum size of radon dosimeters.

  4. Experimental and Monte Carlo simulation studies of open cylindrical radon monitoring device using CR-39 detector

    International Nuclear Information System (INIS)

    Rehman, Fazal-ur-; Jamil, K.; Zakaullah, M.; Abu-Jarad, F.; Mujahid, S.A.

    2003-01-01

    There are several methods of measuring radon concentrations but nuclear track detector cylindrical dosimeters are widely employed. In this investigation, the consequence of effective volumes of the dosimeters on the registration of alpha tracks in a CR-39 detector was studied. In a series of experiments an optimum radius for a CR-39-based open cylindrical radon dosimeter was found to be about 3 cm. Monte Carlo simulation techniques hav been employed to verify the experimental results. In this context, a computer code Monte Carlo simulation dosimetry (MOCSID) was developed. Monte Carlo simulation experiments gave the optimum radius of the dosimeters as 3.0 cm. The experimental results are in good agreement with those obtained by Monte Carlo design calculations. In addition to this, plate-out effects of radon progeny were also studied. It was observed that the contribution of radon progeny ( 218 Po and 214 Po) plated-out on the wall of the dosimeters increases with an increase of dosimeter radii and then decrease to 0 at a radius of about 3 cm if a point detector has been installed at the center of the dosimeter base. In the code MOCSID different types of random number generators were employed. The results of this research are very useful for designing an optimum size of radon dosimeters

  5. Residential radon exposure and lung cancer risk in Misasa, Japan. A case-control study

    International Nuclear Information System (INIS)

    Sobue, Tomotaka; Lee, Valerie S.; Ye, Weimin; Tanooka, Hiroshi; Mifune, Masaaki; Suyama, Akihiko; Koga, Taeko; Morishima, Hiroshige; Kondo, Sohei

    2000-01-01

    In order to investigate an association between residential radon exposure and risk of lung cancer, a case-control study was conducted in Misasa Town, Tottori Prefecture, Japan. The case series consisted of 28 people who had died of lung cancer in the years 1976-96 and 36 controls chosen randomly from the residents in 1976, matched by sex and year of birth. Individual residential radon concentrations were measured for 1 year with alpha track detectors. The average radon concentration was 46 Bq/m 3 for cases and 51 Bq/m 3 for controls. Compared to the level of 24 or less Bq/m 3 , the adjusted odds ratios of lung cancer associated with radon levels of 25-49, 50-99 and 100 or more Bq/m 3 , were 1.13 (95% confidence interval; 0.29-4.40), 1.23 (0.16-9.39) and 0.25 (0.03-2.33), respectively. None of the estimates showed statistical significance, due to small sample size. When the subjects were limited to only include residents of more than 30 years, the estimates did not change substantially. This study did not find that the risk pattern of lung cancer, possibly associated with residential radon exposure, in Misasa Town differed from patterns observed in other countries. (author)

  6. Environmental radon

    International Nuclear Information System (INIS)

    Majumdar, S.K.; Schmalz, R.F.; Miller, E.W.

    1990-01-01

    This book covers many aspects of environmental radon, including: historical perspectives; occurrence and properties; detection, measurement, and mitigation, radon and health; and political, economic, and legislative impacts

  7. Study on indoor radon exposure and its effect on human health

    International Nuclear Information System (INIS)

    Lu Xinwei

    2005-01-01

    Radon and its daughters relate to people health. Radon widely exists in the nature. The paper discusses the source, exposure and activity level of indoor radon, systematically analyzes the hazards and dose-response of residential radon exposure, and at last indicates the concrete method of controlling residential radon concentration. By interdicting radon pollution source and ventilation might effectively reduce indoor radon concentration and improve environmental air quality. (authors)

  8. Soil gas radon response to environmental and soil physics variables

    International Nuclear Information System (INIS)

    Thomas, D.M.; Chen, C.; Holford, D.

    1991-01-01

    During the last three years a field study of soil gas radon activities conducted at Poamoho, Oahu, has shown that the primary environmental variables that control radon transport in shallow tropical soils are synoptic and diurnal barometric pressure changes and soil moisture levels. Barometric pressure changes drive advective transport and mixing of soil gas with atmospheric air; soil moisture appears to control soil porosity and permeability to enhance or inhibit advective and diffusive radon transport. An advective barrier test/control experiment has shown that advective exchange of soil gas and air may account for a substantial proportion of the radon loss from shallow soils but does not significantly affect radon activities at depths greater than 2.3 m. An irrigation test/control experiment also suggests that, at soil moisture levels approaching field capacity, saturation of soil macroporosity can halt all advective transport of radon and limit diffusive mobility to that occurring in the liquid phase. The results of the authors field study have been used to further refine and extend a numerical model, RN3D, that has been developed by Pacific Northwest Laboratories to simulate subsurface transport of radon. The field data have allowed them to accurately simulate the steady state soil gas radon profile at their field site and to track transient radon activities under the influence of barometric pressure changes and in response to changes in soil permeability that result from variations in soil moisture levels. Further work is continuing on the model to enable it to properly account for the relative effects of advective transport of soil gas through cracks and diffusive mobility in the bulk soils

  9. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process that affect the progeny's atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. This report describes the progress toward achieving these objectives.

  10. Diurnal measurement of equilibrium equivalent radon/thoron concentration using time integrated flow mode grab sampler

    International Nuclear Information System (INIS)

    Pant, P.; Kandari, T.; Ramola, R.C.; Semwal, C.P.; Prasad, M.

    2018-01-01

    The basic processes which influenced the concentration of radon and thoron decay products are- attachment, recoil and deposition and by the room specific parameters of radon exhalation and ventilation. The freshly formed decay products have a high diffusivities (especially in air) and ability to stick to surfaces. According to UNSCEAR 1977, radon daughters may be combined as the so called equilibrium equivalent concentration which is related to the potential alpha energy distribution concentration. In the present study an effort has been made to see the diurnal variation of radon and thoron progeny concentration using time integrated flow mode sampler

  11. Measurement of radon permeability through polyethylene membrane using scintillation detector

    Energy Technology Data Exchange (ETDEWEB)

    Ashry, A.H.; Abou-Leila, M. [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Abdalla, A.M., E-mail: aymanabdalla62@hotmail.co [Department of Physics, Faculty of Education, Ain Shams University, Cairo (Egypt); Department of Physics, Faculty of Sciences and Arts, Najran University, Najran, P.O. Box. 11001 (Saudi Arabia); Advanced Materials and Nano-Engineering Laboratory (AMNEL), Centre for Advanced Materials and Nano-Engineering (CAMNE), Najran University, Najran, P.O. Box. 11001 (Saudi Arabia)

    2011-01-15

    The permeability of Radon 222 through polyethylene membranes has been studied using activated charcoal technique. The permeability constant of Radon 222 through low-density polyethylene, linear low-density Polyethylene and high density polyethylene samples has been measured. There is a considerable agreement between the values obtained by our method and the method suggested by W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211], and SSNTD technique suggested by A. Hafez and G. Somogyi [1986. Determination of radon and thoron permeability through some plastics by track technique. Int. J. Radiat. Appl. Instrum. Nucl. Track Radiat. Meas. 12 (1-6), 697-700]. In this work Radon permeability through different polyethylene membranes has been measured using three different methods, i.e. solid state nuclear track technique, W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211]method and our proposed method. In addition to this, in this study, the diffusion coefficient of radon in charcoal as well as solubility of Radon in polyethylene membrane has been taken into consideration.

  12. Measurement of radon permeability through polyethylene membrane using scintillation detector

    International Nuclear Information System (INIS)

    Ashry, A.H.; Abou-Leila, M.; Abdalla, A.M.

    2011-01-01

    The permeability of Radon 222 through polyethylene membranes has been studied using activated charcoal technique. The permeability constant of Radon 222 through low-density polyethylene, linear low-density Polyethylene and high density polyethylene samples has been measured. There is a considerable agreement between the values obtained by our method and the method suggested by W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211], and SSNTD technique suggested by A. Hafez and G. Somogyi [1986. Determination of radon and thoron permeability through some plastics by track technique. Int. J. Radiat. Appl. Instrum. Nucl. Track Radiat. Meas. 12 (1-6), 697-700]. In this work Radon permeability through different polyethylene membranes has been measured using three different methods, i.e. solid state nuclear track technique, W. Arafa [2002. Permeability of radon 222 through some materials. Radiat. Meas. 35, 207-211] method and our proposed method. In addition to this, in this study, the diffusion coefficient of radon in charcoal as well as solubility of Radon in polyethylene membrane has been taken into consideration.

  13. A study on the indoor radon concentrations in hospitals in the Shillong region, Meghalaya

    International Nuclear Information System (INIS)

    Sharma, Yubaraj; Maibam, Deveshwori; Saxena, Atul; Ram, Priya P.; Walia, Devesh

    2015-01-01

    In this paper, we report our findings on radon survey in indoor environment which consists of around 105 rooms in 8 major hospitals in Shillong region and also present experimental estimates on the associated annual effective doses and life-time fatality risks. The survey has been undertaken using LR-115 Type 2 detectors. Radon activity concentration values were found to range from 65.66 Bq.m -3 to 783.77 Bq.m -3 with an arithmetic mean value of 260.4±138.3 Bq.m -3 and a geometric mean value of 228.4±1.67 Bq.m -3 . Distribution analysis of the radon activity concentration measured at the hospital rooms has been carried out. Of the total rooms surveyed, 60% have radon concentration more than the ICRP prescribed lower limit of 200 Bq.m -3 and about 4% of the rooms higher than the upper limit of 600 Bq.m -3 . Floor-wise study has been done and a decrease in radon concentration with increase in floor-number has been observed. (author)

  14. A compact multiparameter acquisition system for radon concentration studies

    Science.gov (United States)

    Pugliese; Baiano; Boiano; D'Onofrio; Roca; Sabbarese; Vollaro

    2000-07-01

    A compact device suitable to acquire and display, at the same time, radon concentrations in a given atmosphere, and the environmental parameters characterising the atmosphere, is presented and described. It consists of two main blocks: (i) a detection section including a set of sensors for measuring pressure, humidity and temperature, and a set of silicon surface barrier detectors mounted in electrostatic cells collecting the ionised radon daughters; (ii) a single NIM module featuring an eight channel 12 bit ADC and the linear electronics to shape the signals from the silicon detectors. The system is controlled by a computer via a RS232 port. The software, implemented in Visual Basic, allows to display the energy distribution of the pulses coming from the alpha detectors and to initialise and control all phases of the acquisition. The results of preliminary tests show the high reliability of the system.

  15. A compact multiparameter acquisition system for radon concentration studies

    International Nuclear Information System (INIS)

    Pugliese, M.; Baiano, G.; Boiano, A.; D'Onofrio, A.; Roca, V.; Sabbarese, C.; Vollaro, P.

    2000-01-01

    A compact device suitable to acquire and display, at the same time, radon concentrations in a given atmosphere, and the environmental parameters characterising the atmosphere, is presented and described. It consists of two main blocks: (i) a detection section including a set of sensors for measuring pressure, humidity and temperature, and a set of silicon surface barrier detectors mounted in electrostatic cells collecting the ionised radon daughters; (ii) a single NIM module featuring an eight channel 12 bit ADC and the linear electronics to shape the signals from the silicon detectors. The system is controlled by a computer via a RS232 port. The software, implemented in Visual Basic, allows to display the energy distribution of the pulses coming from the alpha detectors and to initialise and control all phases of the acquisition. The results of preliminary tests show the high reliability of the system

  16. A study of radon-222 concentrations in North Carolina groundwater

    International Nuclear Information System (INIS)

    Evans, J.P.

    1992-01-01

    The groundwater of 400 North Carolina homes was sampled to ascertain the distribution and extent of 222 Rn in North Carolina groundwater. Arithmetic mean (AM) and geometric mean (GM) concentrations of 1,816 pCi L -1 and 656 pCi L -1 were found for the state. These results indicate that two-thirds of 114 degree C. homes served by groundwater exceed the EPA proposed 300 pCi L -1 maximum contaminant level (MCL). Only 2% of NC homes exceeded 10,000 pCi L-1. The Eastern region had the lowest radon concentrations by far, with a GM of 2-)0 pCi L -1 . The Central region and Western region had GM's of 794 pCi L -1 and 1,032 pCi L -1 respectively. The groundwater data approached a log normal distribution. No consistent trends were noted in the relationship between indoor radon concentrations and groundwater radon concentrations. A correlation coefficient of 0.00921 revealed a very weak linear relationship

  17. Improved radon-flux-measurement system for uranium-tailings pile measurement

    International Nuclear Information System (INIS)

    Freeman, H.D.

    1981-10-01

    The Pacific Northwest Laboratory (PNL) is developing cover technology for uranium mill tailings that will inhibit the diffusion of radon to the atmosphere. As part of this cover program, an improved radon flux measurement system has been developed. The radon measurement system is a recirculating, pressure-balanced, flow-through system that uses activated carbon at ambient temperatures to collect the radon. With the system, an area of 0.93 m 2 is sampled for periods ranging from 1 to 12 h. The activated carbon is removed from the radon trap and the collected radon is determined by counting the 214 Bi daughter product. Development of the system included studies to determine the efficiency of activated carbon, relative calibration measurements and field measurements made during 1980 at the inactive tailings pile in Grand Junction, Colorado. Results of these studies are presented

  18. The significance of radon in radioactive pollution of environment. Pt. 2. Radon effect on living organism

    International Nuclear Information System (INIS)

    Kossakowski, S.; Dziura, A.; Kossakowski, A.

    1998-01-01

    Authors review the history of radon monitoring. Epidemiological studies of lung cancer and its correlation to radon concentration in mines and buildings are described. The influence of radon on animals living in the buildings built from waste materials is described. Authors review plans concerning creation of radon monitoring system in Poland. The necessity of monitoring influence of radon on animals is described

  19. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, July 1, 1992--March 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report describes studies on the chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and its dose to the cells in the respiratory tract are to be fully assessed. The specific tasks of the controlled laboratory studies are to determine the formation rates of {center_dot}OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO{sub 2} ethylene, and H{sub 2}S to lower vapor pressure compounds and determine the role of gas phase additives such as H{sub 2}O and NH{sub 3} in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of {sup 218}Po{sub x}{sup +} in O{sub 2} at low radon concentrations. Tasks of the exposure studies in occupied indoor spaces are to initiate measurements of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants, to initiate a prospective study of the utility of measurement of deposited {sup 210}Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon, and to develop the methodology to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  20. [Experimental study on the influence of natural and artificial ventilation on indoor radon concentration].

    Science.gov (United States)

    Remetti, R; Gigante, G E

    2010-01-01

    The study presents the results of a campaign of measurements on the daily radon concentration using a Genitron Alpha Guard spectrometer. All the measurements have been intended to highlight the radon concentration variability during the 24 hours of the day and trying to find correlations with other ambient parameters such as temperature and pressure or local conditions such as the presence or not of a forced ventilation system. The main part of the measurements have been carried in the area of the Nuclear Measurement Laboratory of the Department of Basic and Applied Sciences for Engineering of "Sapienza" University of Rome. Results show a rapid rise of radon concentration in the night, when the artificial ventilation system was off and with door and windows closed. In the morning, after the opening of door and windows, the concentration falls down abruptly. With artificial ventilation system in function concentration never reaches significant values.

  1. Effect of local geology on indoor radon levels: a case study

    International Nuclear Information System (INIS)

    Hawthorne, A.R.; Gammage, R.B.; Dudney, C.S.

    1984-01-01

    This paper presents the results of radon monitoring in 40 East Tennessee homes that were a component of a larger study to evaluate indoor air quality. Measurements were conducted during two 3-month time periods with passive integrating track etch monitors in each of the forty homes. In a subset of homes, measurements were also conducted with a real-time monitor that provided readings on an hourly basis. The results of the monitoring indicate that about 30% of the homes had radon levels greater that 4 pCi/L in the living space. Homes with elevated radon levels were associated with local variations in geology; most of the homes having higher levels were located on the porous dolomite ridge partially surrounding Oad Ridge, Tennessee. (Author)

  2. Radon concentration studies in houses on the territory of the former German Democratic Republic

    International Nuclear Information System (INIS)

    Lehmann, R.

    1993-01-01

    In cooperation with the Federal Institute of Water, Soil and Air Hygiene, studies have been made since March 1990 in mining centers in the South of the former GDR territory on radon concentration in as many differently used houses as possible, predominantly in dwelling houses, but also in plant buildings, schools, kindergartens, recreation homes, etc. Under this program, measurements were performed until October 1990 in the cities of Schneeberg, Johanngeorgenstadt and Ronneburg and in the municipality of Schlema. The results obtained from this radon screening covering almost the whole affected area, qualitatively correspond to those obtained from small random samples taken under a regional measuring program performed in the respective muncipalities. A summary presentation is given of the range of radon concentration in houses to be expected in East Germany, relating it to geologically different areas in accordance with the present state of knowledge. (orig./DG) [de

  3. Swiss radon programme 'RAPROS'

    International Nuclear Information System (INIS)

    Zeller, W.

    1992-03-01

    The results of the five-year radon research program RAPROS presented in this report, allow for scientifically valid statements on the origin of elevated levels of indoor radon in Switzerland. These results form a basis for recommendations and for actions to be taken. Indoor radon concentrations have been measured in more than 4000 living-rooms and 2000 basements; a sampling density of about 0.2% of the Swiss housing stock. According to these measurements radon leads to an estimated average annual effective dose of 2 milli-Sievert, although in some regions the annual dose may be much higher. Extrapolation of the existing data shows that in about 10'000 Swiss houses radon may exceed 1000 Bq/m 3 . For these houses remedial actions are recommended. There seems to be no radon problem in the large cities in the Swiss Plateau. High indoor radon concentrations in Switzerland are due to the soil beneath the buildings. Data from the study indicated that the most important soil characteristic influencing indoor radon concentrations was its gas permeability. Because natural ventilation in a heated house creates a slight underpressure in the lower levels with respect to surrounding soils, radon is driven from the soil into the building. Weatherization of the houses to reduce energy consumption had in most cases no effect on the indoor radon concentrations. Radon from tap water or from building materials does not contribute significantly to indoor radon levels in Switzerland. The high levels in the Jura Mountains are thought to be associated with karstic limestone bedrock. Several houses within Switzerland have now been modified to reduce radon levels. The most successful mitigation technique combined forced-air ventilation with tightening of the basement to decrease or prevent air infiltration from the soil. (author) figs., tabs., refs

  4. Radon 10 x 10 project: Implantation of geographic information systems in studies of radon in homes and geology catalans

    International Nuclear Information System (INIS)

    Amado Sanjuan, J. L.; Bach Plaza, J.; Baixeras divar, C.; Font Guiteras, L. L.; Moreno Balta, V.

    2013-01-01

    This methodology provides a useful tool to establish relationships between different data in order to identify areas in which to assess the radiological risk that represents radon in the Catalan population and gagging. (Author)

  5. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, May 1, 1993--January 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1993-01-01

    Progress is reported on the chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical processes that affect the progeny`s atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. The specific tasks addressed were to determine the formation rates of {center_dot}OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO{sub 2}, ethylene, and H{sub 2}S to lower vapor pressure compounds and determine the role of gas phase additives such as H{sub 2}O and NH{sub 3} in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of {sup 218}PoO{sub x}{sup +} in O{sub 2} at low radon concentrations. Initial measurements were conducted of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants. A prospective study of the utility of measurement of deposited {sup 210}Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon are described. Methodology was developed to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  6. Calculation of radon emanation from a radiferous pile

    International Nuclear Information System (INIS)

    Zettwoog, Pierre.

    1980-07-01

    The theory of unidimensional diffusion of radon in a porous medium, either radiferous or not, is presented taking into account the effects of humidity and the adsorption of radon on the medium. Experimental procedures for determining the two main characteristics of diffusion in a medium, the relaxation length of the diffusion of radon and the emanating power, are described [fr

  7. Epidemiological study on the cancer mortality in an area with elevated radon daughter exposure

    International Nuclear Information System (INIS)

    Pohl-Rueling, J.

    1983-07-01

    In many countries water containing considerable amounts of Radon-222 is used in so-called ''Radon Spas'' for therapeutical purposes. In the Austrian radon spas Badgastein and Bad Hofgastein many detailed studies of the environmental natural radioactivity have been carried out for about 20 years. The accumulated annual doses to the basal cells of the segmental and subsegmental bronchiols (receiving the highest dose at inhalation of radon and daughters, and target for lung cancer) were calculated for several population groups in this area. The researcher calculated the exposure to radon and daughter accumulated over a lifetime for each single person who lived in Badgastein for at least 10 years and died between 1947 and 1980. The lifetime bronchial doses of 1366 residents who died between 1947 and 1980 from several causes of death were calculated. Altogether 56 lung cancer cases occurred. From that the annual lung cancer incidence rate for Badgastein (30 and 108 per 10 5 living people of all ages and for persons over 40 years respectively) is not statistically different from the mean observed lung cancer cases in the whole Federal Province of Salzburg (32 and 98 respectively). A case-control study has also been carried out to compare the mean annual lifetime exposure of lung cancer deaths with those of other. It can be seen that for the higher exposed population groups and even more so for the miners, the persons who died of lung cancer received a higher dose than those who died of other cancer and other causes. Therefore radon daughter inhalation may be responsible for lung cancer induction even in a non-mining environment

  8. Study of the behavior of automatic track detectors for radon determination

    International Nuclear Information System (INIS)

    Moreno C, A.

    1997-01-01

    Both the alpha decay and the alpha and beta emitting radon daughters, may affect the living cells. In this thesis, experiments have been performed to study the response of environmental radon using different alpha particle detectors. A study was performed both in the laboratory and in the field of two kinds of detectors: a) Passive solid state nuclear track detectors, LR 115 type II, capable to integrate the alpha particles in a given period of time and, b) an automatic active detector, Clipperton, that continuously accumulate the alpha counting from radon decay. LR-115 track detectors were exposed in the laboratory to alpha particles from a radioactive source and a controlled radon atmosphere. The detectors were also exposed to electrons from an electron accelerator. The number of alpha tracks in the detectors were evaluated with two kinds of spark counters. The response of the track detectors as a function of the number of alpha tracks showed a reproducibility of 92%, and the effect of electron doses showed that the bulk etching velocity varied as a function of the electron dose. Additionally some changes were introduced in an SSNTD exchanger, exposed to the radon chamber in order to reduce the background in the non exposed positions. A conversion factor of 0.016 tracks/cm 2 . 10h per Bq/m 3 was obtained. The response of the two spark counters was similar. Field soil radon determinations were performed with track detectors during 11 months and with the active detector during 5 months with exposures each month and each hour respectively. When calculated for the same time periods exposure the response of both systems was similar. However differences were quite striking in the patterns of short and long term exposure periods since short term fluctuations are explicitly shown with the active detector while integrated within the passive one. (Author)

  9. In-vivo measurements of Pb-210 to determine cumulative exposure to radon daughters: A pilot study

    International Nuclear Information System (INIS)

    Laurer, G.R.; Cohen, N.; Stark, A.; Ju, C.

    1991-05-01

    The objective of this study is to demonstrate the feasibility of estimating cumulative exposure of individuals to low concentrations of radon by measuring the amount of Pb-A-10 in their skeletons. This report presents progress to date establishing the validity of an vivo technique to measure skeletal burdens of Pb-210, accumulated from exposure to radon and radon progeny. With the skeletal content of Pb--210 and a model for Pb metabolism, cumulative exposure to radon and its short-lived daughters (radon/daughters) may be calculated for use in deriving a dose-response relationship between lung cancer and exposure to radon/daughters. Data are presented for 29 subjects exposed to ''above-average'' radon concentrations in their homes, showing the correlation between measured Pb--210 burdens, and measured pCi/l and WLM exposure estimates. Their results are compared to measurements of a population of 24 subject's presumed exposed to average concentrations. Measurements of a Pennsylvania family exposed for a year in a home with an extremely high radon content are also presented. Update of results of an ongoing study of the biological half-time of Pb--210 in man involving measurements, of a retired radiation worker with a 40 year old skeletal burden of Pb-210

  10. Radon exhalation rates of concrete modified with fly ash and silica fumes

    International Nuclear Information System (INIS)

    Amit Kumar; Chauhan, R.P.; Mehta, Vimal; Kant, K.

    2013-01-01

    The radiological impact of the environmental gas radon to the health of general public is of concern since many decades. Cement used for the construction blended with fly ash and silica fumes is recommended by Government in order to avoid the soil and environmental pollution. But these addition step-up the Indoor radon level in the dwelling due to radioactivity contents. The exhalation of radon from concrete blended with silica fumes and fly ash depends upon addition level, porosity, moisture and radioactivity content. In order to optimize the level of substitution of silica fumes and fly ash, measurements of radon exhalation rates from the concrete blended with different proportions of fly ash and silica fumes was carried out using active scintillation radon monitor. The effect of porosity, moisture, back diffusion and radioactivity content of the concrete on exhalation rates is studied. The measured exhalation rates were extrapolated for indoor radon concentration and effective dose equivalent using ICRP, 1987 recommendations. (author)

  11. Radon analyser

    International Nuclear Information System (INIS)

    1981-01-01

    The process claimed includes the steps of transferring radon gas produced by a sample to a charcoal trap, cooled to a temperature whereby the radon is absorbed by the charcoal, heating the charcoal trap to a sufficient temperature to release the radon, and transferring the radon to a counting device where the gas particles are counted

  12. Predicting radon flux from uranium mill tailings

    International Nuclear Information System (INIS)

    Freeman, H.D.; Hartley, J.N.

    1983-11-01

    Pacific Northwest Laboratory (PNL), under contract to the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) office, is developing technology for the design of radon barriers for uranium mill tailings piles. To properly design a radon cover for a particular tailings pile, the radon flux emanating from the bare tailings must be known. The tailings characteristics required to calculate the radon flux include radium-226 content, emanating power, bulk density, and radon diffusivity. This paper presents theoretical and practical aspects of estimating the radon flux from an uranium tailings pile. Results of field measurements to verify the calculation methodology are also discussed. 24 references, 4 figures, 4 tables

  13. Integrated source-risk model for radon: A definition study

    International Nuclear Information System (INIS)

    Laheij, G.M.H.; Aldenkamp, F.J.; Stoop, P.

    1993-10-01

    The purpose of a source-risk model is to support policy making on radon mitigation by comparing effects of various policy options and to enable optimization of counter measures applied to different parts of the source-risk chain. There are several advantages developing and using a source-risk model: risk calculations are standardized; the effects of measures applied to different parts of the source-risk chain can be better compared because interactions are included; and sensitivity analyses can be used to determine the most important parameters within the total source-risk chain. After an inventory of processes and sources to be included in the source-risk chain, the models presently available in the Netherlands are investigated. The models were screened for completeness, validation and operational status. The investigation made clear that, by choosing for each part of the source-risk chain the most convenient model, a source-risk chain model for radon may be realized. However, the calculation of dose out of the radon concentrations and the status of the validation of most models should be improved. Calculations with the proposed source-risk model will give estimations with a large uncertainty at the moment. For further development of the source-risk model an interaction between the source-risk model and experimental research is recommended. Organisational forms of the source-risk model are discussed. A source-risk model in which only simple models are included is also recommended. The other models are operated and administrated by the model owners. The model owners execute their models for a combination of input parameters. The output of the models is stored in a database which will be used for calculations with the source-risk model. 5 figs., 15 tabs., 7 appendices, 14 refs

  14. Daily fluctuations in radon concentration in a Cordoba factory complex

    International Nuclear Information System (INIS)

    Germanier, A.; Perez, R.; Rubio, M.

    1998-01-01

    Full text: This work shows the fluctuations of indoor radon concentration in some rooms placed inside a Cordoba Factory Complex. The measurements were performed by Victoreen Radon Monitor. The system was shaped to sample single radon concentration values after one hour integration. It utilizes a passive diffusion chamber and a silicon diffused junction detector. A portion of decay products will plate-out onto the detector and emit alpha particles into the depletion region of a diffused junction detector. The alpha energy is deposited in the detector in the form of ionization which generates a charge pulse. Only alpha pulses of an energy level similar Po-218 and Po-214 are detected. The study of the meteorological parameters shows that the daily fluctuations of the radon concentration respond to the transport and dispersion processes of radon gas through the air. Air temperature, wind's direction and speed are found to be fundamentals parameters in the observed time behavior. The meteorological data were obtained by a portable station (Davis Weathe Monitor II). The radon concentration present a maximum value (1850 Bq/m 3 ) at the night and a minimum value (150 Bq/m 3 ) at the day. (author) [es

  15. Residential radon and lung cancer: a cohort study in Galicia, Spain

    Directory of Open Access Journals (Sweden)

    Raquel Barbosa-Lorenzo

    Full Text Available Case-control studies show an association between residential radon and lung cancer. The aim of this paper is to investigate this association through a cohort study. We designed an ambispective cohort study using the Galician radon map, Spain, with controls drawn from a previous case-control study. Subjects were recruited between 2002 and 2009. The data were cross-checked to ascertain lung cancer incidence and then analysed using a Cox regression model. A total of 2,127 subjects participated; 24 lung cancer cases were identified; 76.6% of subjects were drawn from the radon map. The adjusted hazard ratio was 1.2 (95%CI: 0.5-2.8 for the category of subjects exposed to 50Bq/m3 or more. This risk rose when subjects from the case-control study were analyzed separately. In conclusion, we did not observe any statistically significant association between residential radon exposure and lung cancer; however, it appears that with a sample of greater median age (such as participants from the case-control study, the risk of lung cancer would have been higher.

  16. Monitoring of radon concentration in dwellings

    International Nuclear Information System (INIS)

    Kurosawa, Ryuhei

    1991-01-01

    Radon problems in dwellings have recently received much attention. Radon concentration in dwellings, as well as in the general environment, varies with various factors such as meteorological conditions and soil components. Therefore, a long term monitoring of radon concentration is required to obtain an average concentration. This paper reviews a passive type radon monitor that is handy and allows a long term radon monitoring. It provides the structure and principle of the radon monitor, covering the type, filter function, sensitivity of diffusion collecting type (cup type), electrostatic collecting type, adsorption collecting type, and detector of radon monitor. Actual examples of the radon monitor are also given. Radon daughter nuclides will have become major foci of exposure countermeasures. In the future, the development of a passive type monitor for determining potential alpha energy concentration is required. (N.K.)

  17. Prospect of radon as a tracer in studying of landslide forecast

    International Nuclear Information System (INIS)

    Zhang Huifeng; Ding Dexin

    2004-01-01

    Radon, as a chemical element of radioactivity, is widely used in the fields of earth-quake monitoring, prospecting mine and exploring resource. This paper discussed the theory of radon's separating out from the soil and the theory and means of surveying radon. It also relates the radon anomaly in the measuring process of soil radon, caused by the interferring of the environmental factors in measurement results. It further clarifies the wilde application of radon as a tracer in landslide forecast. (authors)

  18. Radon and radon progeny in 70 houses in the Tennessee Valley area: study design and measurement methods

    International Nuclear Information System (INIS)

    Dudney, C.S.; Hawthorne, A.R.; Monar, K.P.; Quillen, J.L.; Clark, C. Jr.; Doane, R.W.; Wallace, R.G.; Reed, R.P.

    1986-01-01

    Levels of radon and its short-lived airborne progeny are being measured in a year-long study of 70 houses in four states in the Tennessee Valley. Various methods were used to solicit volunteers with differing degrees of success. Criteria for selection of houses in the study included presence of a lower level with cement floor and one or more block walls in contact with the soil, absence of obvious indications of technologically enhanced sources of radium, and proximity to one of four cities (Knoxville, Chattanooga, Birmingham, or Florence). By design, most houses in the study are in the same neighborhood as at least one other house in the study. Houses range in age from newly constructed to about 40 years old. Most of the houses have more than 2000 square feet of finished floor space. The lower level encompasses a garage in most cases. More complete information pertaining to house characteristics will be gathered in the course of the study. 19 refs., 1 fig

  19. Study on radon concentration in nursery school in the mining region

    International Nuclear Information System (INIS)

    Skowronek, J.; Wysocka, M.; Mielnikow, A.

    1999-01-01

    Study on children exposure from natural radon background has been performed on the example of nursery schools being localized in Piekary Slaskie in the coal mining region of Silesia. Indoor air contamination has been measured as well as soil air and air outside the houses. In none of examined places the exposure do not exceeded the IAEA acceptable level

  20. Residential radon exposure and risk of incident hematologic malignancies in the Cancer Prevention Study-II Nutrition Cohort

    Energy Technology Data Exchange (ETDEWEB)

    Teras, Lauren R., E-mail: lauren.teras@cancer.org [Epidemiology Research Program, American Cancer Society, Atlanta, GA (United States); Diver, W. Ryan [Epidemiology Research Program, American Cancer Society, Atlanta, GA (United States); Turner, Michelle C. [Centre for Research in Environmental Epidemiology (CREAL), Barcelona (Spain); Universitat Pompeu Fabra (UPF), Barcelona (Spain); CIBER Epidemiología y Salud Pública (CIBERESP), Madrid (Spain); McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa (Canada); Krewski, Daniel [McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa (Canada); School of Epidemiology, Public Health and Disease Prevention, University of Ottawa, Ottawa, Ontario (Canada); Sahar, Liora [Statistics and Evaluation Center, American Cancer Society, Atlanta, GA (United States); Ward, Elizabeth [Intramural Research, American Cancer Society, Atlanta, GA (United States); Gapstur, Susan M. [Epidemiology Research Program, American Cancer Society, Atlanta, GA (United States)

    2016-07-15

    Dosimetric models show that radon, an established cause of lung cancer, delivers a non-negligible dose of alpha radiation to the bone marrow, as well as to lymphocytes in the tracheobronchial epithelium, and therefore could be related to risk of hematologic cancers. Studies of radon and hematologic cancer risk, however, have produced inconsistent results. To date there is no published prospective, population-based study of residential radon exposure and hematologic malignancy incidence. We used data from the American Cancer Society Cancer Prevention Study-II Nutrition Cohort established in 1992, to examine the association between county-level residential radon exposure and risk of hematologic cancer. The analytic cohort included 140,652 participants (66,572 men, 74,080 women) among which 3019 incident hematologic cancer cases (1711 men, 1308 women) were identified during 19 years of follow-up. Cox proportional hazard regression was used to calculate multivariable-adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for radon exposure and hematologic cancer risk. Women living in counties with the highest mean radon concentrations (>148 Bq/m{sup 3}) had a statistically significant higher risk of hematologic cancer compared to those living in counties with the lowest (<74 Bq/m{sup 3}) radon levels (HR=1.63, 95% CI:1.23–2.18), and there was evidence of a dose-response relationship (HR{sub continuous}=1.38, 95% CI:1.15–1.65 per 100 Bq/m{sup 3}; p-trend=0.001). There was no association between county-level radon and hematologic cancer risk among men. The findings of this large, prospective study suggest residential radon may be a risk factor for lymphoid malignancies among women. Further study is needed to confirm these findings. - Highlights: • This is the first prospective, general population study of residential radon and risk of hematologic cancer. • Findings from this study suggest that residential radon exposure may be a risk factor

  1. Residential radon exposure and risk of incident hematologic malignancies in the Cancer Prevention Study-II Nutrition Cohort

    International Nuclear Information System (INIS)

    Teras, Lauren R.; Diver, W. Ryan; Turner, Michelle C.; Krewski, Daniel; Sahar, Liora; Ward, Elizabeth; Gapstur, Susan M.

    2016-01-01

    Dosimetric models show that radon, an established cause of lung cancer, delivers a non-negligible dose of alpha radiation to the bone marrow, as well as to lymphocytes in the tracheobronchial epithelium, and therefore could be related to risk of hematologic cancers. Studies of radon and hematologic cancer risk, however, have produced inconsistent results. To date there is no published prospective, population-based study of residential radon exposure and hematologic malignancy incidence. We used data from the American Cancer Society Cancer Prevention Study-II Nutrition Cohort established in 1992, to examine the association between county-level residential radon exposure and risk of hematologic cancer. The analytic cohort included 140,652 participants (66,572 men, 74,080 women) among which 3019 incident hematologic cancer cases (1711 men, 1308 women) were identified during 19 years of follow-up. Cox proportional hazard regression was used to calculate multivariable-adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for radon exposure and hematologic cancer risk. Women living in counties with the highest mean radon concentrations (>148 Bq/m 3 ) had a statistically significant higher risk of hematologic cancer compared to those living in counties with the lowest (<74 Bq/m 3 ) radon levels (HR=1.63, 95% CI:1.23–2.18), and there was evidence of a dose-response relationship (HR continuous =1.38, 95% CI:1.15–1.65 per 100 Bq/m 3 ; p-trend=0.001). There was no association between county-level radon and hematologic cancer risk among men. The findings of this large, prospective study suggest residential radon may be a risk factor for lymphoid malignancies among women. Further study is needed to confirm these findings. - Highlights: • This is the first prospective, general population study of residential radon and risk of hematologic cancer. • Findings from this study suggest that residential radon exposure may be a risk factor for lymphoid

  2. Radon in Antarctica

    International Nuclear Information System (INIS)

    Ilic, R.; Rusov, V.D.; Pavlovych, V.N.; Vaschenko, V.M.; Hanzic, L.; Bondarchuk, Y.A.

    2005-01-01

    The paper reviews results of radon measurements obtained in Antarctic research stations in the last 40 years by both active and passive radon monitors. A brief description of the radon laboratory set-up in the Ukrainian Academician Vernadsky station on the Antarctic Peninsula (W 64 o 16 ' , S 65 o 15 ' ), where radon is measured by two types of etched track Rn dosimeter and 4 types of continuous radon monitoring devices is presented. Some selected results of research work are described related to: (i) analysis of radon storms, defined as an abrupt increase of 222 Rn during the occurrence of a cyclone, and its applicability for the study of the transport of air masses of continental origin to Antarctica; (ii) a study of the correlation of changes of radon concentration and geomagnetic field induced by tectonic activity and its application to predicting tectonomagnetic anomalies, and (iii) verification of a newly developed theoretical model based on noise analysis of the measured radon signal for earthquake prediction. Suggestions for future utilization of radon for basic research in Antarctica (and not only in Antarctica) conclude the contribution. conclude the contribution

  3. Radon Measurements in Vojvodina

    International Nuclear Information System (INIS)

    Bikit, I.; Bikit, K.; Forkapic, S.; Mrda, D.; Nikolov, J.; Todorovic, N.; Veskovic, M.

    2013-01-01

    Recent analyses of epidemiological studies of lung cancer risk from residential exposures demonstrate a statistically significant increase per unit of exposure below average annual concentrations of about 200 Bq/m 3 . Indoor radon measurements performed in Novi Sad in about 400 houses and flats are presented and discussed in this paper. By measuring gamma-activity of radon daughters, radon activity concentration was determined to be 50 Bq/m 3 . In Vojvodina region indoor radon levels were measured by alpha track detectors CR-39 on about 3000 locations during the winter seasons in the period of three years (2003-2005). The main aim of the present study was to explore the critical group of population for radon exposure and to estimate maximal annual doses. Existing radon maps which identify regions with elevated radon levels will improve data collection and analysis for the future radon campaigns. Collaboration on the JRC program of European indoor radon map and implementation of grid system are also discussed.(author)

  4. Small area mapping of domestic radon, smoking prevalence and lung cancer incidence – A case study in Northamptonshire, UK

    International Nuclear Information System (INIS)

    Denman, Antony R.; Rogers, Stephen; Ali, Akeem; Sinclair, John; Phillips, Paul S.; Crockett, Robin G.M.; Groves-Kirkby, Christopher J.

    2015-01-01

    Smoking and radon both cause lung cancer, and together the risk is significantly higher. UK public health campaigns continue to reduce smoking prevalence, and other initiatives identify houses with raised radon (radon-222) levels and encourage remedial action. Smoking prevalence and radon levels in the UK have been mapped at Primary Care Trust level. This paper extends that work, using a commercial socio-demographic database to estimate smoking prevalence at the postcode sector level, and to predict the population characteristics at postcode sector level for 87 postcode sectors in Northamptonshire. Likely smoking prevalence in each postcode sector is then modelled from estimates of the smoking prevalence in the different socio-economic groups used by the database. Mapping estimated smoking prevalence, radon potential and average lung cancer incidence for each postcode sector suggested that there was little correlation between smoking prevalence and radon levels, as radon potential was generally lower in urban areas in Northamptonshire, where the estimates of smoking prevalence were highest. However, the analysis demonstrated some sectors where both radon potential and smoking prevalence were moderately raised. This study showed the potential of this methodology to map estimated smoking prevalence and radon levels to inform locally targeted public health campaigns to reduce lung cancer incidence. - Highlights: • We use a commercial socio-demographic database to estimate smoking prevalence in small areas in Northamptonshire, UK. • We map the estimated smoking prevalence and average domestic radon levels in these small areas. • We estimate annual average lung cancer incidence in these small areas. • The methodology is useful to evaluate and plan localised public health campaigns to reduce lung cancer incidence.

  5. Study on calculation models and distribution rules of the radon concentration and its progenies concentration in blind roadway with forced-exhaust ventilation

    International Nuclear Information System (INIS)

    Ye Yongjun; Wang Liheng; Zhou Xinghuo; Li Xiangyang; Zhong Yongming; Wang Shuyun; Ding Dexin

    2014-01-01

    The forced-exhaust ventilation is an important way to control the concentration of radon and its progenies in long-distance blind driving roadway. It is of great significance for guiding the design of ventilation and radiation protection to study distribution characteristics of the concentration of radon and its progenies in the wind of roadway adopting the forced-exhaust ventilation. Therefore, according to the decay relationship of radon and its progenies, a simplified mathematical calculation model was built, which relates to the radon activity concentration and the potential alpha concentration of radon progenies. The paper also analyzed the sources of radon and its progenies in the limited space of the blind roadway. Then, based on the turbulence mass transfer theory of ventilation air flow, the paper established mathematical calculation models of distribution characteristics of the radon activity concentration and the potential alpha concentration of radon progenies in blind roadway with forced-exhaust ventilation, respectively. Finally, the paper applied the calculation models to a special blind roadway, and discussed the influence of the ventilation air inflow and the radon exhalation rate of rock wall on the distribution of radon concentration and the potential alpha concentration of radon progenies in the roadway. Meanwhile, some protective measurements were put forward to reduce the radiation dose of worker caused by radon and its progenies in the blind roadway. (authors)

  6. Study of radon-222 emanation from sedimentary phosphates and corresponding phosphogypsum. Temperature effect

    International Nuclear Information System (INIS)

    Boujrhal, F.M.

    1993-01-01

    The aim of this study is to examine the effect of temperature on radon emanation from the phosphates of various regions of Morocco, from corresponding phosphogypsum and from teeth fossilized of Youssoufia phosphate. The interpretation of obtained results was carried out by the physicochemical studies with various approaches; the X-ray diffraction analysis, the measurement of the specific surface area and porousness, the determination of the oxygen content by activation analysis with 14 MeV neutron. The thermal treatment between 100 and 900 degrees C conducted to the following points: - An increase of the radon degassing rate, which is first slow when the temperature increase from 20 to 600 degrees C, then becomes brutal beyond this temperature. We attributed this variation to the training effect ( transport effect ) of radon by the others gas susceptible to be released with thermal effect, particularly the CO sub 2. - The reduction of the radon emanation power versus temperature. We could demonstrate a linear correlation between the power emanation and the specific surface area. 122 refs., 102 figs., 20 tabs. (Author)

  7. Radon in Schools

    Science.gov (United States)

    ... Search Search Radon Contact Us Share Radon in Schools Related Information Managing Radon in Schools Radon Measurement ... Radon Could Be a Serious Threat to Your School Chances are you've already heard of radon - ...

  8. Study of lung cancer and residential radon in the Czech Republic

    International Nuclear Information System (INIS)

    Tomasek, L.; Mueller, T.; Kunz, E.; Heribanova, A.; Matzner, J.; Placek, V.; Burian, I.; Holecek, J.

    2001-01-01

    The lung cancer mortality study was designed as a follow-up study of the population (N = 12,004) in a radon-prone area in the Czech Republic, covering the 1960-1999 period. Information on the vital status and causes of death was mostly obtained from local authorities and extracted from the national population registry. Exposure estimates were based on one-year measurements of radon progeny in the majority of houses within the study area (74 %). Exposures outside the area (16%) were based on radon mapping of the Czech Republic. The mean concentration, 509 Bq/m 3 , is five-fold higher than the country-wide average. By 1999, a total of 210 lung cancers had been observed, which is somewhat more than the nationally expected value (O/E = 1.10), as compared to the generally low numbers regarding cancer types other than lung cancer (O/E = 0.81). The excess relative risk for the standard radon concentration (100 Bq/m 3 ) was 0.087 (90 % CI: 0.017-0.208), which is consistent with the risk coefficients derived from other indoor studies. The increased lung cancer incidence was found to depend linearly on exposure in terms of the mean radon concentration during the past 5-34 years. The estimate was not affected appreciably by adjustment to smoking; although the risk coefficient was higher for non-smokers than for smokers (0.130 vs 0.069), the difference was not statistically significant

  9. Does balneotherapy with low radon concentration in water influence the endocrine system? A controlled non-randomized pilot study.

    Science.gov (United States)

    Nagy, Katalin; Berhés, István; Kovács, Tibor; Kávási, Norbert; Somlai, János; Bender, Tamás

    2009-08-01

    Radon bath is a well-established modality of balneotherapy for the management of degenerative musculoskeletal disorders. The present study was conducted to ascertain whether baths of relatively low (80 Bq/l) radon concentration have any influence on the functioning of the endocrine system. In the study, a non-randomized pilot study, 27 patients with degenerative musculoskeletal disorders received 30-min radon baths (of 31-32 degrees C temperature and 80 Bq/l average radon concentration) daily, for 15 days. Twenty-five patients with matching pathologies were subjected to balneotherapy according to the same protocol, using thermal water with negligible radon content (6 Bq/l). Serum thyroid stimulating hormone, prolactin, cortisol, adrenocorticotropic hormone, and dehydroepiandrosterone levels were measured before and after a balneotherapy course of 15 sessions. Comparison of the accumulated data using the Wilcoxon test did not reveal any significant difference between pre- and post-treatment values or between the two patient groups. It is noted that while the beneficial effects of balneotherapy with radon-containing water on degenerative disorders is widely known, only few data have been published in the literature on its effect on endocrine functions. The present study failed to demonstrate any substantial effect of thermal water with relatively low radon content on the functioning of the endocrine system.

  10. Comparative survey of outdoor, residential and workplace radon concentrations

    International Nuclear Information System (INIS)

    Barros, Nirmalla; Field, R. William; Field, Dan W.; Steck, Daniel J.

    2015-01-01

    This study investigated radon concentrations in above-ground (i.e. first floor) workplace in Missouri and compared them with above-ground radon concentrations in nearby homes and outdoor locations. This study also examined the potential utility of using home and outdoor radon concentrations to predict the radon concentration at a nearby workplace (e.g. county agencies and schools). Even though workplace radon concentrations were not statistically different from home radon concentrations, the radon concentration at a particular home, or outdoor location, was a poor predictor of the radon concentration at a nearby workplace. Overall, 9.6 and 9.9 % of homes and workplace, respectively, exhibited radon concentrations of ≥148 Bq m -3 . Because of the percentage of workplace with elevated radon concentrations, the results suggest that additional surveys of workplace radon concentrations are needed, especially in areas of high radon potential, to assess the contribution of workplace radon exposure to an individual's overall radon exposure. (authors)

  11. Controlled study of the evolution of radon and its decay products in radioactive mine environments

    International Nuclear Information System (INIS)

    Calizaya A, F.

    1985-01-01

    This thesis discusses three aspects related to radon emissions and control of radon decay products in mine environments: (1) measurement of the effects of environmental parameters on radiation levels, (2) analysis of the data using ordinary linear regression and transfer function models and (3) prediction of the concentration of radioactive contaminants in the mine air. In-mine and laboratory experiments were conducted to develop the research data. In mine tests were conducted in a bulkhead isolated mine drift containing low grade uranium ore at the Colorado School of Mines, Experimental Mine with the US Bureau of Mines - Spokane Research Center (USBM, SRC) micro-computer based radiation monitoring system. Parameters such as amount of ore, amount of condensation nuclei in the mine air, temperature, air velocity, and barometric pressure were studied. The laboratory tests were conducted in an air-tight radon chamber equipped with a container of the radioactive material, various monitors, and the USBM, SRC Data Acquisition System. The effect of parameters such as ore grade, particle size, rock moisture, air temperature and relative humidity on radon concentrations were measured in the laboratory. Radiation levels, together with parameters affecting these levels, were measured over a period of one year (June 1984-July 1985) both in the laboratory model and in the field

  12. Experimental study of the combined effect of cigarette smoke and an active burden of radon-222

    International Nuclear Information System (INIS)

    Chameaud, J.; Perraud, R.; Chretien, J.; Masse, R.; Lafuma, J.

    1978-01-01

    Previous studies on the carcinogenic effect of radon-222 derivatives have yielded accurate relationships, for each radon dose, between the dose value and the frequencies and latency times of lung cancers. In the present work, one hundred rats were subjected, over one-and-a-half months, to a total dose of 3600 WLM, chosen because it corresponds to a 30% occurrence of cancers. Fifty of these animals then inhaled cigarette smoke during 50 ten-minute sessions per week. The total time for these inhalations was 350 hours spread over about six months. In the 'radon' group (50 rats), 17 animals were found to have lung cancer. In the 'radon + tobacco' group (50 rats), 32 cancers were observed; moreover, the tumours in this group were much more extensive, multifocal and invasive. Animals subjected to cigarette smoke alone have never shown lung cancer. The effect of tobacco as a co-factor in carcinogenesis has thus been varified experimentally, although inhaled cigarette smoke alone is not carcinogenic in rats. (author)

  13. Study on radon concentration in groundwater of Sira and Tiptur taluk of Tumkur district, Karnataka, India

    Directory of Open Access Journals (Sweden)

    M B Karthik Kumar

    2017-01-01

    Full Text Available A study on radon concentration in groundwater samples collected from different villages of Sira and Tiptur taluk of Tumkur district has been conducted using emanometry method, and the effective dose to the public was estimated. The geometric mean of the activity concentration of dissolved radon was found to be 39.13 ± 1.99 and 3.78 ± 0.05 Bq/L for Sira and Tiptur taluk, respectively. The total annual effective dose for adult, children, and infants was also estimated and was found to be 0.20, 0.18, and 0.31 mSv/year, respectively, in Sira taluk and 0.019, 0.017, and 0.029 mSv/year in Tiptur taluk, respectively. Water samples were also analyzed for the physicochemical parameters to assess the quality of drinking water and also to understand the influence of these parameters on dissolved radon concentration. Poor correlation was observed between dissolved radon concentration and pH in both taluks.

  14. Studies on possibility for alleviation of lifestyle diseases by low-dose irradiation or radon inhalation

    International Nuclear Information System (INIS)

    Kataoka, T.; Sakoda, A.; Yoshimoto, M.; Nakagawa, S.; Toyota, T.; Nishiyama, Y.; Yamato, K.; Ishimori, Y.; Kawabe, A.; Hanamoto, K.; Taguchi, T.; Yamaoka, K.

    2011-01-01

    Our previous studies showed the possibility that activation of the anti-oxidative function alleviates various oxidative damages, which are related to lifestyle diseases. Results showed that, low-dose X-ray irradiation activated superoxide dismutase and inhibits oedema following ischaemia-reperfusion. To alleviate ischaemia-reperfusion injury with transplantation, the changes of the anti-oxidative function in liver graft using low-dose X-ray irradiation immediately after exenteration were examined. Results showed that liver grafts activate the anti-oxidative function as a result of irradiation. In addition, radon inhalation enhances the anti-oxidative function in some organs, and alleviates alcohol-induced oxidative damage of mouse liver. Moreover, in order to determine the most effective condition of radon inhalation, mice inhaled radon before or after carbon tetrachloride (CCl 4 ) administration. Results showed that radon inhalation alleviates CCl 4 -induced hepatopathy, especially prior inhalation. It is highly possible that adequate activation of anti-oxidative functions induced by low-dose irradiation can contribute to preventing or reducing oxidative damages, which are related to lifestyle diseases. (authors)

  15. Numerical study of turbulent diffusion

    International Nuclear Information System (INIS)

    McCoy, M.G.

    1975-01-01

    The problem of the numerical simulation of turbulent diffusion is studied. The two-dimensional velocity fields are assumed to be incompressible, homogeneous and stationary, and they are represented as stochastic processes. A technique is offered which creates velocity fields accurately representing the input statistics once a two point correlation function or an energy spectrum is given. Various complicated energy spectra may be represented utilizing this model. The program is then used to extract information concerning Gaussian diffusion processes. Various theories of other workers are tested including Taylor's classical representation of dispersion for times long compared with the Lagrangian correlation time. Also, a study is made of the relation between the Lagrangian and the Eulerian correlation function and a hypothesis is advanced and successfully tested. Questions concerning the relation between small eddies and the energy spectrum are considered. A criterion is advanced and successfully tested to decide whether small scale flow can be detected within the large eddies for any given spectrum. A method is developed to determine whether this small scale motion is in any sense periodic. Finally, the relation between two particle dispersion and the energy spectrum is studied anew and various theories are tested

  16. Radon 10 x 10 project: Implantation of geographic information systems in studies of radon in homes and geology catalans; Proyecto radon 10x10: aplicacion de los sistemas de informacion geografica en estudios de radon y geologia en viviendas catalanas

    Energy Technology Data Exchange (ETDEWEB)

    Amado Sanjuan, J. L.; Bach Plaza, J.; Baixeras divar, C.; Font Guiteras, L. L.; Moreno Balta, V.

    2013-07-01

    This methodology provides a useful tool to establish relationships between different data in order to identify areas in which to assess the radiological risk that represents radon in the Catalan population and gagging. (Author)

  17. Radon in the Houses of Virovitica and Podravina County

    International Nuclear Information System (INIS)

    Varga Pajtler, M.; Miklavcic, I.; Poje, M.; Radolic, V.; Vukovic, B.; Ivkovic, I.; Jurisic, D.

    2011-01-01

    222Ra is the gaseous radioactive product of the decay of radium isotope 226Ra which is present in soil. Radon atoms that are released from the ground are transported by diffusion and then released in the atmosphere. Radon entries into buildings by advection that is driven by the pressure difference between the building and the ground around the foundation. The aim of this study was to measure radon concentrations in the houses of Virovitica and Podravina county. The measurements were performed by means of two passive track detectors LR-115 (Kodak-Pathe, France), one of which (the open detector) detected total number of alpha-particles of radon and its short-lived progeny, while the other (diffusion detector) registerd tracks only of alpha particles emitted by radon. After being exposed to radiation, the LR-115 detectors were etched in 10 % NaOH aqueous solution at 60 degrees of C for 120 minutes and the detector tracks were counted. Radon concentrations in air were determined according to equation (1), where D 0 was the number of tracks per one day of exposure of the open detector and k is the sensitivity coefficient od the person that counted the tracks. For the track densities D and D 0 of the open and diffusion detectors, respectively, the equilibrium factor was calculated according to equation (2), with the parameters a = 0,50, and b = -0,53. Obtained value for the equilibrium factor was 0,85. Measurements gave radon concentrations in the range of 5.7 - 187.7 Bq m -3 . Average annual effective radon dose for population of Virovitica and Podravina county is 1,5 mSv. (author)

  18. Study of the behaviour of radon in soil and the interpretation of radon anomalies in the exploration for uranium

    International Nuclear Information System (INIS)

    Bhatnagar, A.S.

    1975-04-01

    The report presents detailed tables of data on radon distribution patterns to enable an interpretation of the anomalies to be carried out in the process of exploration for uranium. The distribution of radon in soils fits into a lognormal pattern. In places where uranium mineralization exists, the distribution pattern is a two lognormal one. This method can be used to classify areas and delineate them according to the distribution pattern found over them. The field work was carried out in the Delhi area, in Turumdih and in Udaisagar

  19. Radon exhalation study from cement, cement slabs and concrete slabs with variation in fly ash

    International Nuclear Information System (INIS)

    Sharma, Nisha; Singh, Jaspal

    2012-01-01

    Fly ash is a waste product from coal-fired power plants. Fly ash has become a subject of world-wide interest in recent years because of its diverse uses, e.g. in the manufacture of concrete for building purposes, for the filling of underground cavities, or as a component of building material. The fly ash may contain enhanced levels of the natural radionuclides in the uranium and thorium series and by using the fly ash in building materials, the radiation levels in houses may thus be technologically enhanced. Because of its relatively high radionuclide contents (including 226 Ra), fly ash may, however, present a potential hazard to the population through its radon emanation, which would be highly undesirable. Since fly ash is frequently used as a building material, the idea of the experiment was to mix fly ash in different proportions in the cement in the powder form, cemented slabs and concrete slabs to study the combined behaviors. Alpha sensitive LR-115 type II plastic track detector, commonly known as Solid State Nuclear Track Detectors (SSNTDs), were used to measure the radon concentration. The alpha particles emitted from the radon causes the radiation damaged tracks. The chemical etching in NaOH at 60°C for about 90 minutes was done to reveal these latent tracks, which were then scanned and counted by an optical microscope of suitable magnification. By calculating the track density of registered tracks, the radon concentrations were determined. In case of cement in the powder form and in cemented slab, starting from the pure cement, fly ash was added up to 70% by weight. In this case the radon exhalation rate has increased by addition of fly ash in the cement and in case of concrete slabs by the addition of fly ash in the cement the radon exhalation increases up to 60% and then decreases. Therefore, on the basis of our investigations we concluded that in general radon exhalation rate increases with the addition of fly ash. (author)

  20. Radon generation and transport. A journey though matter

    Energy Technology Data Exchange (ETDEWEB)

    Cozmuta, I. [Beckman Institute 139-74 Caltech, Pasadena, CA 91125 (United States)

    2001-12-07

    The transport of radon in concrete takes place through the complicated network of interconnected pores that is, at any time, the result of the process of hydration of cement and of moisture distribution and transport. Initially the microstructure of concrete depends on the mix proportions and curing conditions, its time-evolution being conditioned by its surrounding environment. Radon transport will be consequently a function of time, as it is influenced by the changing microstructure (total porosity and its distribution) and by the amount and distribution of the moisture contained in the pore system. A selection of information from the large amount of literature available on concrete is presented in chapter 2. A model that describes the process of hydration, of microstructure development and of moisture transport is presented in chapter 3. The physics of radon diffusion in homogeneous porous materials is outlined in chapter 4. The coupling of the numerical implementation of the hydration and radon transport (chapter 6) offers the possibility to achieve calculated values for porosity and moisture content thus, reducing the number of material parameters in the radon-transport equation that have to be determined experimentally. Chapter 7 covers the experimental methods and techniques. Chapter 5 presents a survey of the information available in literature on radon release from concrete and on radon barriers. This chapter also summarises results of several experimental studies investigating the radon reduction efficiency and also the permeability of various covers. On basis of this information, a selection was made for the covering materials to be assessed in this thesis. Radon-release rates of uncovered and completely covered concrete samples were measured. From these measurements the reduction efficiencies of various sealants (epoxy glue, double-sided aluminised polyethylene foil, soluble glass) were calculated (chapter 12). Also, as a result of the collaboration

  1. Radon generation and transport. A journey though matter

    International Nuclear Information System (INIS)

    Cozmuta, I.

    2001-01-01

    The transport of radon in concrete takes place through the complicated network of interconnected pores that is, at any time, the result of the process of hydration of cement and of moisture distribution and transport. Initially the microstructure of concrete depends on the mix proportions and curing conditions, its time-evolution being conditioned by its surrounding environment. Radon transport will be consequently a function of time, as it is influenced by the changing microstructure (total porosity and its distribution) and by the amount and distribution of the moisture contained in the pore system. A selection of information from the large amount of literature available on concrete is presented in chapter 2. A model that describes the process of hydration, of microstructure development and of moisture transport is presented in chapter 3. The physics of radon diffusion in homogeneous porous materials is outlined in chapter 4. The coupling of the numerical implementation of the hydration and radon transport (chapter 6) offers the possibility to achieve calculated values for porosity and moisture content thus, reducing the number of material parameters in the radon-transport equation that have to be determined experimentally. Chapter 7 covers the experimental methods and techniques. Chapter 5 presents a survey of the information available in literature on radon release from concrete and on radon barriers. This chapter also summarises results of several experimental studies investigating the radon reduction efficiency and also the permeability of various covers. On basis of this information, a selection was made for the covering materials to be assessed in this thesis. Radon-release rates of uncovered and completely covered concrete samples were measured. From these measurements the reduction efficiencies of various sealants (epoxy glue, double-sided aluminised polyethylene foil, soluble glass) were calculated (chapter 12). Also, as a result of the collaboration

  2. Studying radon exhalation rates variability from phosphogypsum piles in the SW of Spain

    Energy Technology Data Exchange (ETDEWEB)

    López-Coto, I., E-mail: israel.lopez@dfa.uhu.es [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain); Mas, J.L. [Dpto. Física Aplicada I. Escuela Politécnica Superior, University of Sevilla, C/Virgen de Africa 7, 41012 Sevilla (Spain); Vargas, A. [Universitat Politècnica de Catalunya, Instituto de Técnicas Energéticas, Campus Sud Edificio ETSEIB, Planta 0, Pabellón C, Av. Diagonal 647, 08028 Barcelona (Spain); Bolívar, J.P. [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain)

    2014-09-15

    Highlights: • Variability of radon exhalation rates from PG piles has been studied using numerical simulation supported by experimental data. • Most relevant parameters controlling the exhalation rate are radon potential and moisture saturation. • Piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. • A proposed cover here is expected to allow exhalation rates reductions up to 95%. - Abstract: Nearly 1.0 × 10{sup 8} tonnes of phosphogypsum were accumulated during last 50 years on a 1200 ha disposal site near Huelva town (SW of Spain). Previous measurements of exhalation rates offered very variable values, in such a way that a worst case scenario could not be established. Here, new experimental data coupled to numerical simulations show that increasing the moisture contents or the temperature reduces the exhalation rate whilst increasing the radon potential or porosity has the contrary effect. Once the relative effects are compared, it can be drawn that the most relevant parameters controlling the exhalation rate are radon potential (product of emanation factor by {sup 226}Ra concentration) and moisture saturation of PG. From wastes management point of view, it can be concluded that piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. Furthermore, a proposed cover here is expected to allow exhalation rates reductions up to 95%. We established that the worst case scenario corresponds to a situation of extremely dry winter. Under these conditions, the radon exhalation rate (0.508 Bq m{sup −2} s{sup −1}) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bq m{sup −2} s{sup −1})

  3. A retrospective study of radon daughter concentrations in the workplace in the fluorspar mines of St. Lawrence, Newfoundland

    International Nuclear Information System (INIS)

    Corkhill, D.A.; Dory, A.B.

    1984-07-01

    Fluorspar mining began in St. Lawrence, Newfoundland in the early thirties. In the early years the existing economic and social conditions resulted in poor health and safety practices in the mines. A high incidence of many types of pulmonary diseases, including lung cancer, among the miners was investigated by the Department of National Health and Welfare, and by 1960 radiation in the mines was recognized as the major cause. The original epidemiological study used radon daughter exposure estimates determined from a limited number of radon daughter measurements in one of the mines. Insufficient experience existed at that time to allow a proper technical assessment of the mines and to modify the estimated radon daughter concentrations accordingly. A review of the environmental conditions in the early years of mining and a revision of the estimates of radon daughter concentrations in those mines is presented. Environmental working conditions were determined based on a review of maps, inspectors' reports, Commission hearings, recollections of former workers and of the authors. Comparison to the conditions in the mines in later years, when radiation samples were taken more frequently allowed estimations of the probable radon daughter concentrations that would have existed in the mines earlier. Ranges of estimated average concentrations were made by mines for each year and wherever possible for broad types of job classes. Rather than attempting to propose single numbers for radon daughter concentrations, which in turn might have implied an accuracy that did not exist, ranges of average radon daughter concentrations were estimated

  4. A study on the radon concentrations in water in Jeddah (Saudi Arabia) and the associated health effects

    International Nuclear Information System (INIS)

    Tayyeb, Z.A.; Kinsara, A.R.; Farid, S.M.

    1998-01-01

    Several studies have shown that water-borne 222 Rn contributes to indoor air concentrations. A passive radon measurement method was employed to determine radon activity concentrations in the water of Jeddah city (Saudi Arabia). Tap water, flushing water and drinking water, including natural mineral water, artificial mineral water and distilled water, have been investigated for their radon concentrations. It is observed that the radon concentration in natural mineral water samples is the highest and that in flush water, it is the lowest. From these measurements, the corresponding annual effective dose for the stomach and the lung are determined. It is found that the annual effective dose resulting from direct consumption of water is far greater than that due to inhalation of radon emanated from tap water and flushing water. Moreover, it is also seen that the annual effective dose resulting from inhalation of radon emanated from tap water and flushing water is negligible compared to the total annual effective dose for indoor radon in Jeddah. (author)

  5. The effect and the amendment of thermoregulation to the stability of radon concentration in radon chamber

    International Nuclear Information System (INIS)

    Zhang Xiongjie; Wang Renbo; Qu Jinhui; Tang Bin; Zhu Zhifu; Man Zaigang

    2010-01-01

    When the temperature in the airtight radon chamber was adjusted, it would induce the frequent changes of the air pressure in chamber, then the radon concentration in the radon chamber would continuously reduce, which could seriously destroy the stability of the radon concentration in radon chamber. In this paper, on the study of the effect reasons to the stability of radon concentration in airtight radon chamber due to the thermoregulation, a new amendment scheme was put forward, and the solutions of the relevant parameters were discussed. The amendment scheme had been successfully applied to HD-6 radon chamber, and achieved good results. (authors)

  6. Experimental methods for studying the diffusion of radioactive gases in solids. VII. Sorption method

    International Nuclear Information System (INIS)

    Bekman, I.N.

    1983-01-01

    The details of the use of a sorption method in the study of the diffusion of gasses and vapors labeled with radioactive tracers in solids have been considered. Three variants of diffusion systems, which permit the determination of the diffusion coefficient and the solubility constant of gases both from the increase in the amount of diffusate in the sample and from the decrease in its amount in the reservoir, have been tested. Different ways of conducting the experiment have been discussed. A universal method for taking into account the processes of the absorption and scattering of radiation in the material of the sample has been proposed. The experimental results were treated with the aid of a specially developed program package, which is realized on computers of the BESM-6 type. Various mathematical models of the diffusion of gases in solids have been analyzed. Solutions of the diffusion equations under the boundary conditions of the sorption method for the cases of diffusion with trapping, dissociative diffusion, and diffusion in a plate containing spherical inclusions have been obtained. The method has been tested in the example case of the diffusion of a radiative inert gas, viz., radon-22, in low-density polyethylene

  7. Radon determination by activated charcoal adsorption and liquid scintillation measurement

    International Nuclear Information System (INIS)

    Lopez, F.O.; Canoba, A.C.

    1998-01-01

    A passive diffusion method for the determination of radon concentration has been optimised and calibrated. The device consists of a scintillation vial containing activated charcoal, a diffusion barrier and a desiccant agent. The response to diverse atmospheric humidity and variable exposure intervals was studied. The result is a detector, which is independent of atmospheric humidity for at least (up to) 7 days of exposure. The method was compared with electret detectors (US EPA) with very satisfactory results. The advantages of this method are its simplicity, low cost, low detection limit, the total automatization of the measurement and its total independence of humidity to measure in a wide range of radon concentrations. (author) [es

  8. Radon in the Houses of Slavonski Brod-Posavina County

    International Nuclear Information System (INIS)

    Poleto, Z.; Varga, M.; Radolic, V.; Poje, M.; Vukovic, B.

    2008-01-01

    Radon is a noble alpha-emitting radioactive gas produced by the decay od radium. The aim of this study was to measure radon concentrations in the houses of Slavonski Brod-Posavina county. The measurements were performed by means of the passive track etching method with strippable LR-115 SSNDT film, type II (Kodak-Pathe, France). The cylindrical plastic vessel of detector, with the diameter and the length of 11 and 7 cm, respectively, was covered with a paper filter of 0.078 kg/m 3 surface density. Inside, of the bottom of the vessel, a LR-115 film that presented a diffusion detector was fixed.Outside, on the cylindrical shell of the vessel, another film, that presented the open detector was fixed. The open LR-115 detector registers the total number of alpha-particles of radon and its short-lived progeny, while the diffusion detector registers tracks only of alpha particles emitted by radon. Measurements gave radon concentrations in the range of 14-404 Bq m -3 . Average annual effective radon dose for population of Slavonski Brod-Posavina county is 2.91 mSv

  9. Radon measurements with a PIN photodiode

    International Nuclear Information System (INIS)

    Martin-Martin, A.; Gutierrez-Villanueva, J.L.; Munoz, J.M.; Garcia-Talavera, M.; Adamiec, G.; Iniguez, M.P.

    2006-01-01

    Silicon photodiodes are well suited to detect alphas coming from different sources as neutron reactions or radon daughters. In this work a radon in air detecting device, using an 18x18 mm silicon PIN photodiode is studied. The ionized airborne decay products formed during radon diffusion were focused by an accelerating high voltage to the PIN surface. Several conducting rings were disposed inside a cylindrical PVC vessel in such a way that they reproduced the electric field created by a punctual charge located behind PIN position. Alpha spectra coming from the neutral and ionized species deposited on the PIN surface, dominated by 218 Po and 214 Po progeny peaks, were recorded for varying conditions. Those include radon concentration from a Pylon source, high voltage (thousands of volts) and PIN inverse bias voltage. Different parameters such as temperature and humidity were also registered during data acquisition. The increase in the particle collection efficiency with respect to zero electric field was compared with the corresponding to a parallel plates configuration. A discussion is made in terms of the most appropriate voltages for different radon concentrations

  10. Accumulation of radon in the underground detector cups

    International Nuclear Information System (INIS)

    Qiu Yuanhuo.

    1985-01-01

    Theoretical calculations based on the radon migration mechanism (i. e. diffusion, convection and atmospheric pumping etc) show that the balance of radon concentration in underground detector cups buried and in surrounding soil gas requires about 0.7-10 hours. However, the equilibrium of radon with its daughter products in the cups needs about 4 hours. Therefore, it is considered that 4.5-12 hours are needed for these two processes. It takes 3-4 days for Tn to reach radioactive equilibrium with its short-lived daughter products. When thorium concentration is higher than background exposure time of the detector cups should be over 3-4 days. Using buried detector cups, field experiments give correlative results compared with those of theoretical calculations. The study is oriented both for optimizing the burial time of the detector cup and interpretation of radon anomalies detected

  11. Indoor radon variations in central Iran and its geostatistical map

    Science.gov (United States)

    Hadad, Kamal; Mokhtari, Javad

    2015-02-01

    We present the results of 2 year indoor radon survey in 10 cities of Yazd province in Central Iran (covering an area of 80,000 km2). We used passive diffusive samplers with LATEX polycarbonate films as Solid State Nuclear Track Detector (SSNTD). This study carried out in central Iran where there are major minerals and uranium mines. Our results indicate that despite few extraordinary high concentrations, average annual concentrations of indoor radon are within ICRP guidelines. When geostatistical spatial distribution of radon mapped onto geographical features of the province it was observed that risk of high radon concentration increases near the Saqand, Bafq, Harat and Abarkooh cities, this depended on the elevation and vicinity of the ores and mines.

  12. Health effects of water-borne radon: review of a proposed study. Final report

    International Nuclear Information System (INIS)

    1986-01-01

    The Science Advisory Board's Radiation Advisory Committee was requested to review the scientific merit of a proposal to conduct an epidemiological study of radon in indoor air. The Board accepted the request and formed a Radioepidemiology Subcommittee which responded to two overriding scientific issues: Can further epidemiological study contribute to an understanding of the risks of lung cancer associated with household exposures. The Subcommittee concludes that scientific uncertainties in current epidemiological studies (chiefly studies of uranium miners) could be further reduced through direct investigations of the domestic population. Is the proposed study under review by the Office of Research and Development, entitled Health Effects of Waterborne Radon, appropriately designed to address the risk. For reasons cited in the attached report, the Subcommittee concludes that it is not appropriately designed

  13. Laboratory studies on the removal of radon-born lead from KamLAND's organic liquid scintillator

    Science.gov (United States)

    Keefer, G.; Grant, C.; Piepke, A.; Ebihara, T.; Ikeda, H.; Kishimoto, Y.; Kibe, Y.; Koseki, Y.; Ogawa, M.; Shirai, J.; Takeuchi, S.; Mauger, C.; Zhang, C.; Schweitzer, G.; Berger, B. E.; Dazeley, S.; Decowski, M. P.; Detwiler, J. A.; Djurcic, Z.; Dwyer, D. A.; Efremenko, Y.; Enomoto, S.; Freedman, S. J.; Fujikawa, B. K.; Furuno, K.; Gando, A.; Gando, Y.; Gratta, G.; Hatakeyama, S.; Heeger, K. M.; Hsu, L.; Ichimura, K.; Inoue, K.; Iwamoto, T.; Kamyshkov, Y.; Karwowski, H. J.; Koga, M.; Kozlov, A.; Lane, C. E.; Learned, J. G.; Maricic, J.; Markoff, D. M.; Matsuno, S.; McKee, D.; McKeown, R. D.; Miletic, T.; Mitsui, T.; Motoki, M.; Nakajima, Kyo; Nakajima, Kyohei; Nakamura, K.; O`Donnell, T.; Ogawa, H.; Piquemal, F.; Ricol, J.-S.; Shimizu, I.; Suekane, F.; Suzuki, A.; Svoboda, R.; Tajima, O.; Takemoto, Y.; Tamae, K.; Tolich, K.; Tornow, W.; Watanabe, Hideki; Watanabe, Hiroko; Winslow, L. A.; Yoshida, S.

    2015-01-01

    The removal of radioactivity from liquid scintillator has been studied in preparation of a low background phase of KamLAND. This paper describes the methods and techniques developed to measure and efficiently extract radon decay products from liquid scintillator. We report the radio-isotope reduction factors obtained when applying various extraction methods. During this study, distillation was identified as the most efficient method for removing radon-born lead from liquid scintillator.

  14. Laboratory studies on the removal of radon-born lead from KamLAND's organic liquid scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Keefer, G., E-mail: gregkeefer@llnl.gov [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States); Grant, C. [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States); Piepke, A. [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa 277-8583 (Japan); Ebihara, T.; Ikeda, H. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Kishimoto, Y. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa 277-8583 (Japan); Kibe, Y.; Koseki, Y.; Ogawa, M.; Shirai, J.; Takeuchi, S. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Mauger, C.; Zhang, C. [W.K. Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States); Schweitzer, G. [Department of Chemistry, University of Tennessee, Knoxville, TN 37996 (United States); Berger, B.E. [Department of Physics, Colorado State University, Fort Collins, CO 80523 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa 277-8583 (Japan); Dazeley, S. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Decowski, M.P. [Physics Department, University of California, Berkeley, Berkeley, CA 94720 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa 277-8583 (Japan); Detwiler, J.A. [Physics Department, University of California, Berkeley, Berkeley, CA 94720 (United States); Djurcic, Z. [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States); and others

    2015-01-01

    The removal of radioactivity from liquid scintillator has been studied in preparation of a low background phase of KamLAND. This paper describes the methods and techniques developed to measure and efficiently extract radon decay products from liquid scintillator. We report the radio-isotope reduction factors obtained when applying various extraction methods. During this study, distillation was identified as the most efficient method for removing radon-born lead from liquid scintillator.

  15. Membrane barriers for radon gas flow restrictions

    International Nuclear Information System (INIS)

    Archibald, J.F.

    1984-08-01

    Research was performed to assess the feasibility of barrier membrane substances, for use within mining or associated high risk environments, in restricting the diffusion transport of radon gas quantities. Specific tests were conducted to determine permeability parameters of a variety of membrane materials with reference to radon flow capabilities. Tests were conducted both within laboratory and in-situ emanation environments where concentrations and diffusion flows of radon gas were known to exist. Equilibrium radon gas concentrations were monitored in initially radon-free chambers adjacent to gas sources, but separated by specified membrane substances. Membrane barrier effectiveness was demonstrated to result in reduced emanation concentrations of radon gas within the sampling chamber atmosphere. Minimum gas concentrations were evidenced where the barrier membrane material was shown to exhibit lowest radon permeability characteristics

  16. Radon in Croatian spas

    International Nuclear Information System (INIS)

    Radolic, V.; Vukovic, B.; Planinic, J.

    2004-01-01

    There are ten thermal spas in Croatia and all of them provide health services for patients and visitors. Radon measurements were performed since there is a lack of data concerning natural radioactivity originated from radon and its short-lived progenies in such environments. The thermal water at two different sites (the indoor swimming pool with geothermal water and the spring) in each spa was sampled and radon concentrations were measured by AlphaGUARD radon measuring system. The obtained values were in the range of 0.7 to 19 Bq.dm -3 and 2 to 94 Bq.dm -3 for indoor swimming pools and springs, respectively. Integrated measurements of radon concentration in air were performed by two solid state nuclear track detectors LR-115 II (open and diffusion one) thus enabling estimation of equilibrium factor between radon and its daughters. The annual effective doses received by spa workers were found to be about 1 mSv/y (below the lower limit value of 3 mSv/y recommended by ICRP 65). The doses of patients and visitors were one or two order of magnitude lower than that of the personnel. (author)

  17. Residential radon exposure, diet and lung cancer: a case-control study in a Mediterranean region.

    Science.gov (United States)

    Bochicchio, Francesco; Forastiere, Francesco; Farchi, Sara; Quarto, Maria; Axelson, Olav

    2005-05-10

    We performed a case-control study in Lazio, a region in central Italy characterized by high levels of indoor radon, Mediterranean climate and diet. Cases (384) and controls (404) aged 35-90 years were recruited in the hospital. Detailed information regarding smoking, diet and other risk factors were collected by direct interview. Residential history during the 30-year period ending 5 years before enrollment was ascertained. In each dwelling, radon detectors were placed in both the main bedroom and the living room for 2 consecutive 6-month periods. We computed odds ratios (ORs) and 95% confidence intervals (CIs) for time-weighted radon concentrations using both categorical and continuous unconditional logistic regression analysis and adjusting for smoking, diet and other variables. Radon measurements were available from 89% and 91% of the time period for cases and controls, respectively. The adjusted ORs were 1.30 (1.03-1.64), 1.48 (1.08-2.02), 1.49 (0.82-2.71) and 2.89 (0.45-18.6) for 50-99, 100-199, 200-399 and 400+ Bq/m(3), respectively, compared with 0-49 Bq/m(3) (OR = 1; 0.56-1.79). The excess odds ratio (EOR) per 100 Bq/m(3) was 0.14 (-0.11, 0.46) for all subjects, 0.24 (-0.09, 0.70) for subjects with complete radon measurements and 0.30 (-0.08, 0.82) for subjects who had lived in 1 or 2 dwellings. There was a tendency of higher risk estimates among subjects with low-medium consumption of dietary antioxidants (EOR = 0.32; -0.19, 1.16) and for adenocarcinoma, small cell and epidermoid cancers. This study indicates an association, although generally not statistically significant, between residential radon and lung cancer with both categorical and continuous analyses. Subjects with presumably lower uncertainty in the exposure assessment showed a higher risk. Dietary antioxidants may act as an effect modifier.

  18. A retrospective mortality study of workers exposed to radon in a Brazilian coal mine

    International Nuclear Information System (INIS)

    Veiga, Lene Holanda Sadler

    2004-08-01

    High levels of radon concentration were found in the underground workplace of an underground coal mine in Parana state, which has been in activity since 1942. Many of these workers were exposed for a long period of time to a work atmosphere with high radon, and radon decay products concentration. Taking this into account, it was decided to carry on a historical cohort, study with the workers' of this mining universe (underground and surface) in. order to evaluate the possible health effects related to this exposure, by means of a retrospective study of mortality. Through multiple strategies, it was possible to trace the vital status of 90% of the cohort. The causes of the deaths were identified by active search, of Death Declarations in the Health Office of Parana state and also in and other states. The success rate of cause of death identification was 100%. The final, cohort included 1946 underground workers and 910 surface workers. Standard mortality ratio (SMR) analysis showed lower mortality from all causes for both underground (SMR-88, 95%CI=78-98) and surface workers (SMR=96, 95%CI=81- 113). A highly significant SMR was observed for pneumonia cause of death among surface ((SMR=284, 95%CI=118-684) and underground miners (SMR-254, 95%CI=140-459), while a highly significant lung cancer mortality risk was observed only for underground miners (SMR=177, 95%CI=105-299) with a significant trend in relation to years of underground work (duration of exposure). Taking into account that mortality from smoking-related cancers other than lung cancer is not elevated in underground workers and diesel equipment were not used at this mine, the results suggest that the exposure to radon daughters may have been responsible for the lung cancer excess among underground workers. This work consists of the first historical Brazilian cohort involving miners exposed to radon and one of the few historical cohorts built in Brazil. It should be considered the fact that many workers of

  19. Risks from radon

    International Nuclear Information System (INIS)

    Doll, Richard

    1992-01-01

    The best estimate of risk to which everyone is exposed from natural radon in buildings is now obtained by extrapolation from observations on men exposed to radon in mines. The relationship between dose and effect derived by the US National Research Council implies that about 6% of the current life-time risk of developing the disease in the UK is attributable to radon, but for residents of some houses it will be much greater. This estimate is dependent on many assumptions, some of which are certainly wrong, and reliable estimates can be obtained only by direct observations on people living in different houses. It is possible that radon may also cause some risk of other cancers, notably leukaemia, but such risks, if real, are certainly small. Studies in progress should provide reliable estimates of all radon induced risks within a few years. (author)

  20. Chemical properties of radon

    International Nuclear Information System (INIS)

    Stein, L.

    1986-01-01

    Radon is frequently regarded as a totally inert element. It is, however, a ''metalloid'' - an element which lies on the diagonal of the Periodic Table between the true metals and nonmetals and which exhibits some of the characteristics of both. It reacts with fluorine, halogen fluorides, dioxygenyl salts, fluoro-nitrogen salts, and halogen fluoride-metal fluoride complexes to form ionic compounds. Several of the solid reagents can be used to collect radon from air but must be protected from moisture, since they hydrolyze readily. Recently, solutions of nonvolatile, cationic radon have been produced in nonaqueous solvents. Ion-exchange studies have shown that the radon can be quantitatively collected on columns packed with either Nafion resins or complex salts. In its ionic state, radon is able to displace H + , Na + , K + , Cs + , Ca 2+ , and Ba 2+ ions from a number of solid materials. 27 refs., 6 figs

  1. Standardization of radon measurements

    International Nuclear Information System (INIS)

    Matuszek, J.M.; Hutchinson, J.A.; Lance, B.H.; Virgil, M.G.; Mahoney, R.J.

    1988-01-01

    Radon escaping from soil into homes appears to present the single greatest source of radiation exposure that most people will ever face. Measurement protocols for the relatively inert gas inextricably link the method of collection with the counting of the specimen. The most commonly used methods depend on the measurement of dislocation sites on plastic α-track detectors or on the adsorption of radon onto activated charcoal for subsequent counting of the γ-rays produced by decay of the radon progeny. The uncertainties inherent to the radon-measurement methods used commercially in the United States are far greater than those for measurements of other environmental radionuclides. The results of this preliminary study raise doubts as to whether existing proficiency-testing programs can provide assurance that radon-measurement methods are representative of actual conditions in any dwelling. 17 refs., 1 figs., 4 tabs

  2. Radon therapy; Radon in der Therapie

    Energy Technology Data Exchange (ETDEWEB)

    Spruck, Kaija [Technische Hochschule Mittelhessen, Giessen (Germany). Inst. fuer Medizinische Physik und Strahlenschutz

    2017-04-01

    Radon therapies are used since more than 100 years in human medicine. Today this method is controversially discussed due to the possible increase of ionizing radiation induced tumor risk. Although the exact mode of biological radiation effect on the cell level is still not known new studies show the efficiency of the radon therapy without side effect for instance for rheumatic/inflammatory or respiratory disorders.

  3. Radon surveys and their implications

    International Nuclear Information System (INIS)

    Miles, J.C.H.; Cliff, K.D.; Dixon, D.W.; Green, B.M.R.; Strong, J.C.

    1989-01-01

    In the UK, as in other countries, radon daughter inhalation is the most significant cause of human exposure to ionising radiation either at home or at work whether one considers the mean or the maximum dose. Substantial studies of radon are under way in the UK, and the importance of radon is recognised in several spheres. NRPB investigations of the radon levels in buildings and mines are reported, the distributions of doses presented and risk factors calculated. The bases of radon limitation for workers and members of the public are given and the means of compliance discussed. (author)

  4. Health effects of radon

    International Nuclear Information System (INIS)

    Easterly, C.

    1994-01-01

    Exposure of people to radon has taken on increased interest during the last decade because of the understanding that buildings can serve to trap radon and its daughters, and thereby build up undesirable concentrations of these radioactive elements. Numerous studies of underground miners (often uranium miners) have shown an increased risk of lung cancer in comparison with nonexposed populations. Laboratory animals exposed to radon daughters also develop lung cancer. The abundant epidemiological and experimental data have established the carcinogenicity of radon progeny. Those observations are of considerable importance, because uranium, from which radon and its progeny arise, is ubiquitous in the earth's crust, including coal mines. Risk estimates of the health effects of long-term exposures at relatively low levels require continued development, especially to address the potential health effects of radon and radon daughters in homes and occupational settings where the exposure levels are less than levels in underground uranium and other metal mines that have been the subject of epidemiological studies. Two approaches can be used to characterize the lung-cancer risks associated with radon-daughter exposure: mathematical representations of the respiratory tract that model radiation doses to target cells and epidemiological investigation of exposed populations, mainly underground uranium miners. The mathematically-based dosimetric approach provides an estimate of lung cancer risk related to radon-daughter exposure based specifically on modeling of the dose to target cells. The various dosimetric models all require assumptions, some of which are not subject to direct verification, as to breathing rates; the deposition of radon daughters in the respiratory tract; and the type, nature, and location of the target cells for cancer induction. The most recent large committee effort drawn together to evaluate this issue was sponsored by the National Research Council

  5. Radon in homes and risk of lung cancer: 13 collaborative analyses of individual data from European case-control studies

    International Nuclear Information System (INIS)

    Darby, S.; Hill, D.; Doll, R.; Auvinen, A.; Barros Dios, J.M.; Ruano Ravina, A.; Baysson, H.; Tirmarche, M.; Bochicchio, F.; Deo, H.; Falk, R.; Forastiere, F.; Hakama, M.; Heid, I.; Schaffrath Rosario, A.; Wichmann, H.E.; Kreienbrock, L.; Kreuzer, M.; Lagarde, F.; Pershagen, G.; Makelainen, I.; Ruosteenoja, E.; Muirhead, C.; Oberaigner, W.; TomaBek, L.; Whitley, E.

    2007-01-01

    Objective: To determine the risk of lung cancer associated with exposure at home to the radioactive disintegration products of naturally occurring radon gas. Design: Collaborative analysis of individual data from 13 case-control studies of residential radon and lung cancer. Setting: Nine European countries. Subjects: 7148 cases of lung cancer and 14 208 controls. Main outcome measures: Relative risks of lung cancer and radon gas concentrations in homes inhabited during the previous 5-34 years measured in becquerels (radon disintegrations per second) per cubic metre (Bq/m3) of household air. Results: The mean measured radon concentration in homes of people in the control group was 97 Bq/m3, with 11% measuring > 200 and 4% measuring > 400 Bq/m3. For cases of lung cancer the mean concentration was 104 Bq/m3. The risk of lung cancer increased by 8.4% (95% confidence interval 3.0% to 15.8%) per 100 Bq/m3 increase in measured radon (P=0.0007). This corresponds to an increase of 16% (5% to 31%) per 100 Bq/m3 increase in usual radon- that is, after correction for the dilution caused by random uncertainties in measuring radon concentrations. The dose-response relation seemed to be linear with no threshold and remained significant (P = 0.04) in analyses limited to individuals from homes with measured radon < 200 Bq/m3. The proportionate excess risk did not differ significantly with study, age, sex, or smoking. In the absence of other causes of death, the absolute risks of lung cancer by age 75 years at usual radon concentrations of 0, 100, and 400 Bq/m3 would be about 0.4%, 0.5%, and 0.7%, respectively, for lifelong non-smokers, and about 25 times greater (10%, 12%, and 16%) for cigarette smokers. Conclusions: Collectively, though not separately, these studies show appreciable hazards from residential radon, particularly for smokers and recent ex-smokers, and indicate that it is responsible for about 2% of all deaths from cancer in Europe. (author)

  6. Radon emanation from backfilled mill tailings in underground uranium mine.

    Science.gov (United States)

    Sahu, Patitapaban; Mishra, Devi Prasad; Panigrahi, Durga Charan; Jha, Vivekananda; Patnaik, R Lokeswara; Sethy, Narendra Kumar

    2014-04-01

    Coarser mill tailings used as backfill to stabilize the stoped out areas in underground uranium mines is a potential source of radon contamination. This paper presents the quantitative assessment of radon emanation from the backfilled tailings in Jaduguda mine, India using a cylindrical accumulator. Some of the important parameters such as (226)Ra activity concentration, bulk density, bulk porosity, moisture content and radon emanation factor of the tailings affecting radon emanation were determined in the laboratory. The study revealed that the radon emanation rate of the tailings varied in the range of 0.12-7.03 Bq m(-2) s(-1) with geometric mean of 1.01 Bq m(-2) s(-1) and geometric standard deviation of 3.39. An increase in radon emanation rate was noticed up to a moisture saturation of 0.09 in the tailings, after which the emanation rate gradually started declining with saturation due to low diffusion coefficient of radon in the saturated tailings. Radon emanation factor of the tailings varied in the range of 0.08-0.23 with the mean value of 0.21. The emanation factor of the tailings with moisture saturation level over 0.09 was found to be about three times higher than that of the absolutely dry tailings. The empirical relationship obtained between (222)Rn emanation rate and (226)Ra activity concentration of the tailings indicated a significant positive linear correlation (r = 0.95, p < 0.001). This relationship may be useful for quick prediction of radon emanation rate from the backfill material of similar nature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Biological basis of inhalation exposure of radon and its daughters

    International Nuclear Information System (INIS)

    Matsuoka, Osamu

    1989-01-01

    Since inhalation exposure by radon and its daughters is very specific type of internal exposure, it is necessary to understand its characteristic nature. The specificity originates from the nuclear feature of radon daughters and the biological micro-environment in the respiratory tract. Inhaled radon and its daughters exist in the respiratory tract as ions attached to air dusts and deposit on the mucus surface of the respiratory tract by various mechanisms such as impaction, sedimentation and diffusion. Deposition of radon daughters is predominant around the site of the fourth generation according to Weibel's model. Deposited particles with radon daughters are cleared by muco-ciliary transportation. Its speed is estimated to be about 1.0 cm/min, at the upper region. Alpha decay will happen during transportation in the respiratory tract. Radon has no tissue affinity metabolically. Therefore, the irradiation is limited to the epithelial cells of respiratory tract. The cell components within 30-70 micron in depth are irradiated with alpha particle. Biological effectiveness of alpha radiation is very high compared with beta or gamma radiation. The target cell for carcinogenesis by radon exposure is considered to be the basal cell of epithelium. Lung cancer induced by radon inhalation is recognized to be squamous cell carcinoma, small cell carcinoma, or oat-cell carcinoma and adenocarcinoma. The modification factors which influence the effect of radon exposure are co-inhalation of ore dust and smoking habit. According to epidemiological studies on lung cancer which occurred in uranium miners, it is suggested that the smoking habit strongly promotes lung cancer induction. (author)

  8. Study on seasonal variation of indoor radon, thoron and their progeny levels in Hassan District of Karnataka, India

    International Nuclear Information System (INIS)

    Srinivasa, E.; Rangswamy, D.R.; Sannappa, J.

    2015-01-01

    Radon, thoron and their progeny concentrations have been measured in different types of buildings at different locations for different seasons in Hassan city using time-integrated passive radon dosimeters containing LR-115 Type II solid state nuclear track detector exposed for four seasons of 3 months each covering a period of one year from October 2012 to September 2013. The radon and thoron activity concentration in summer season in the corresponding dwellings has been found to vary from 7.4 to 45.7 Bq m -3 and 5.4 to 34.9 Bqm -3 with a median of 23.59±11 Bqm -3 and 1447±8 Bq -3 respectively. The radon progeny concentrations varies from 0.4 to 4.1 mWL with an average value of 1.83±1 mWL, while thoron progeny concentrations vary from 0.3 to 3.2 mWL with an average value of 1.12±0.7 mWL respectively. The annual effective dose received due to radon, thoron and its progeny by the inhabitants in the dwellings under study has also been calculated which is found to vary from 0.320±0.4 to 1.860 ±1.1 mSv y -1 with an average value of 0.9576 ± 0.8 mSv y -1 . In general, the level of radon-thoron was observed highest in winter and lowest in summer. A detail analysis of radon and thoron distribution in different houses with seasonal variation is presented in this paper. From this study it is observed that, bathrooms and kitchens have significantly higher radon concentrations as compared to other rooms in the dwellings. (author)

  9. Effect of local geology on indoor radon levels: a case study

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, A.R.; Gammage, R.B.; Dudney, C.S.

    1984-01-01

    This paper presents the results of radon monitoring in 40 East Tennessee homes that were a component of a larger study to evaluate indoor air quality. Measurements were conducted during two 3-month time periods with passive integrating track etch monitors in each of the forty homes. In a subset of homes, measurements were also conducted with a real-time monitor that provided readings on an hourly basis. The results of the monitoring indicate that about 30% of the homes had radon levels were associated with local variations in geology; most of the homes having higher levels were located on the porous dolomite ridge partially surrounding Oak Ridge, Tennessee. 7 references, 3 figures, 2 tables.

  10. Effect of local geology on indoor radon levels: a case study

    International Nuclear Information System (INIS)

    Hawthorne, A.R.; Gammage, R.B.; Dudney, C.S.

    1984-01-01

    This paper presents the results of radon monitoring in 40 East Tennessee homes that were a component of a larger study to evaluate indoor air quality. Measurements were conducted during two 3-month time periods with passive integrating track etch monitors in each of the forty homes. In a subset of homes, measurements were also conducted with a real-time monitor that provided readings on an hourly basis. The results of the monitoring indicate that about 30% of the homes had radon levels were associated with local variations in geology; most of the homes having higher levels were located on the porous dolomite ridge partially surrounding Oak Ridge, Tennessee. 7 references, 3 figures, 2 tables

  11. Animal study on biological responses by radon inhalation making use of waste rock which contains feeble activity of uranium (Joint research)

    International Nuclear Information System (INIS)

    Ishimori, Yuu; Sakoda, Akihiro; Tanaka, Hiroshi; Mitsunobu, Fumihiro; Yamaoka, Kiyonori; Kataoka, Takahiro; Yamato, Keiko; Nishiyama, Yuichi

    2013-06-01

    Okayama University and the Japan Atomic Energy Agency (JAEA) have carried out the collaborative study of physiological effects of inhaled radon for the low-dose range. Main assignments were as follows. Based on the clinical knowledge, Misasa Medical Center (Okayama University Hospital) clarified the issues that should be addressed. Graduate School of Health Sciences (Okayama University) supervised the research and studied the biological responses. The JAEA made the development and control of a facility for radon inhalation experiments and the investigation of biokinetics and absorbed doses of radon. From 2007 to 2011, the following results were obtained. (1) Literature on effects of radon for the low-dose range was surveyed to determine the present tasks. (2) The first Japanese large-scale facility was developed for radon inhalation experiments with small animals. (3) Relationships between radon concentration and inhalation time were widely examined to understand the change in antioxidative functions due to radon, which are the most basic parameters. (4) Inhibitory effects of radon on oxidative damages were observed using model mice with reactive oxygen- or free radical-related diseases like alcohol-induced oxidative damages and type I diabetes. (5) In order to discuss biological responses quantitatively following radon inhalation, the biokinetics of inhaled radon was examined and the model for calculation of absorbed doses for organs and tissues was obtained. (author)

  12. Radon in workplaces

    International Nuclear Information System (INIS)

    Reichelt, A.; Lehmann, K.-H.; Reineking, A.; Porstendoerfer, J.; Schwedt, J.; Streil, T.

    2000-01-01

    The radiological assessment of the results of radon measurements in dwellings is not automatically applicable to workplaces due to different forms of utilization, constructional conditions, time of exposure, heating and ventilation conditions, additional aerosol sources, aerosol parameters, chemical substances, etc. In order to investigate the peculiarities of the radon situation in workplaces located inside buildings compared with that in dwellings, long-time recordings of radon, attached radon progeny and unattached radon progeny concentrations ( 218 Po, 214 Pb, 214 Bi) are carried out at several categories of workplaces (e.g. offices, social establishments, schools, production rooms, workshops, kitchens, agricultural facilities). 36 workplaces have been investigated. There have been carried out at least 2-3 long-time recordings for each workplace during different seasons. At the same time the gamma dose rate, meteorological conditions, aerosol particle concentrations have been registered. Many special dates from the workplaces and the buildings have been recorded. Activity size distribution of the aerosol-attached and unattached fraction of short-lived radon decay products have been determinated in 20 workplaces. Mainly the following measurement systems were used: Radon- and Radon Progeny Monitor EQF 3020, SARAD GmbH, Germany. Alpha-Track Radon Detectors, BfS Berlin, Germany. Screen Diffusion Batteries with Different Screens, University of Goettingen, Germany. Low-Pressure Cascade Impactor, Type BERNER. Condensation Nuclei Counter, General Electric, USA. PAEC-f p -Rn-Monitor, University of Goettingen, Germany. Through the measurements, many peculiarities in the course of the radon-concentration, the equilibrium factor F, the unattached fraction f p and the activity size distribution have been determined. These amounts are influenced mainly by the working conditions and the working intervals. The influence of these peculiarities in workplaces on the dose have

  13. Studies on radon concentration at the work places of Mysuru, Bengaluru, Tumkuru and Kolar Districts of Karnataka State, South India

    International Nuclear Information System (INIS)

    Ningappa, C.; Reddy, K. Umesha; Rangaswamy, D.R.; Sannappa, J.

    2015-01-01

    Radon is a radioactive noble gas and is the decay product of naturally occurring uranium. It decays into radioactive metal ions polonium-218 and polonium-214 by alpha radiation, which are harmful to the human health. The concentrations of radon and its progeny inside a given working place depends on activity of radium both in the soil surrounding the workplace and in the building materials, atmospheric conditions, design of the workplace, porosity of the surrounding soil, building layout, and the ventilation habits of the inhabitants of the building. The estimation of dose due to radon and its progeny to the general public and workers at work places are very important. Thus, concentration of radon and its progeny and dose due to radon and its progeny to the public and workers were measured at sixty workplaces of Mysuru, Bengaluru, Tumkur and Kolar districts based on geology and willingness of the workplace owner using twin cup dosimeter based on Solid State Nuclear Track Detectors (SSNTDs) and results are discussed in the present study. The values measured indoor radon in the area of study ranged from a 11.6 to 284.8 Bq.m -3 . (author)

  14. Radon Research Program, FY 1991

    International Nuclear Information System (INIS)

    1992-03-01

    The scientific information being sought in this program encompasses research designed to determine radon availability and transport outdoors, modeling transport into and within buildings, physics and chemistry of radon and radon progeny, dose response relationships, lung cancer risk, and mechanisms of radon carcinogenesis. The main goal of the DOE/OHER Radon Research Program is to develop information to reduce these uncertainties and thereby provide an improved health risk estimate of exposure to radon and its progeny as well as to provide information useful in radon control strategies. Results generated under the Program were highlighted in a National Research Council report on radon dosimetry. The study concluded that the risk of radon exposure is 30% less in homes than in mines. This program summary of book describes the OHER FY-1991 Radon Research Program. It is the fifth in an annual series of program books designed to provide scientific and research information to the public and to other government agencies on the DOE Radon Research Program

  15. Determination of indoor radon concentrations at the elementary schools of Fatih district in Istanbul

    Energy Technology Data Exchange (ETDEWEB)

    Kurt, A., E-mail: aziz.kurt@istanbul.edu.tr; Yalcin, L. Sahin, E-mail: latife.sahin@gmail.com; Oktem, Y., E-mail: sgyks@istanbul.edu.tr; Akkus, B., E-mail: akkus@istanbul.edu.tr; Bozkurt, E., E-mail: enginbozkurt88@gmail.com; Hafizoglu, N., E-mail: nurgulhfz87@gmail.com; Ozturk, F. C., E-mail: fcaglaozturk@gmail.com; Aytan, O., E-mail: ozgur@aytan.net; Ertoprak, A., E-mail: aysegulertoprak@gmail.com [Istanbul University, Science Faculty, Physics Department, 34134, Istanbul (Turkey)

    2016-03-25

    Radon is an odorless, tasteless, colorless noble radioactive gas which is produced within the radioactive decay chain of Uranium. The Radon forms in rocks, diffuses into soil and then escapes into atmosphere. When human exposure to high concentration of radon gas from inside, risk of developing lung cancer is increased. There are many methods to determine {sup 222}Rn concentration in the air. In this study, radon concentration of confined air spaces were measured by using LR-115 solid state nuclear track detectors. 509 LR-115 nuclear trace detectors were placed to 25 schools in Fatih District and they effective dose values were calculated. The results of measurements showed that the radon concentration varies between 40-395 Bq/m{sup 3}. This results compared with Turkey’s limits (400 Bq/m{sup 3}) are low, conversely higher compared with WHO’s limits (100 Bq/m{sup 3}).

  16. Distribution of radon and radium in the ocean and its bearing on some oceanographic problems

    International Nuclear Information System (INIS)

    Miyake, Y.; Sugimura, Y.; Saruhashi, K.

    1980-01-01

    Radon and radium contents in seawater near the ocean floor and in the surface layer of the ocean were studied. The results showed a fairly large amount of excess of radon over radium (1520 to 315%) near the ocean floor. The vertical eddy-diffusion coefficient, D, near the seabed was calculated from a vertical distribution of the excess amount of radon. In the surface layer of the ocean, a remarkable deficiency of radon with respect to radium (50 to 70%) was observed. The mass balance of radium in the mixed layer was considered using a box model. The results showed that the residence time of radon in the mixed layer was about 8 days

  17. Comparative study on the inhibitory effects of antioxidant vitamins and radon on carbon tetrachloride-induced hepatopathy

    International Nuclear Information System (INIS)

    Kataoka, Takahiro; Nishiyama, Yuichi; Yamato, Keiko; Teraoka, Junichi; Morii, Yuji; Taguchi, Takehito; Yamaoka, Kiyonori; Sakoda, Akihiro; Ishimori, Yuu

    2012-01-01

    We have previously reported that radon inhalation activates anti-oxidative functions and inhibits carbon tetrachloride (CCl 4 )-induced hepatopathy. It has also been reported that antioxidant vitamins can inhibit CCl 4 -induced hepatopathy. In the current study, we examined the comparative efficacy of treatment with radon, ascorbic acid and α-tocopherol on CCl 4 -induced hepatopathy. Mice were subjected to intraperitoneal injection of CCl 4 after inhaling approximately 1000 or 2000 Bq/m 3 radon for 24 h, or immediately after intraperitoneal injection of ascorbic acid (100, 300, or 500 mg/kg bodyweight) or α-tocopherol (100, 300, or 500 mg/kg bodyweight). We estimated the inhibitory effects on CCl 4 -induced hepatopathy based on hepatic function-associated parameters, oxidative damage-associated parameters and histological changes. The results revealed that the therapeutic effects of radon inhalation were almost equivalent to treatment with ascorbic acid at a dose of 500 mg/kg or α-tocopherol at a dose of 300 mg/kg. The activities of superoxide dismutase, catalase, and glutathione peroxidase in the liver were significantly higher in mice exposed to radon than in mice treated with CCl 4 alone. These findings suggest that radon inhalation has an anti-oxidative effect against CCl 4 -induced hepatopathy similar to the anti-oxidative effects of ascorbic acid or α-tocopherol due to the induction of anti-oxidative functions. (author)

  18. Radon and thoron levels, their spatial and seasonal variations in adobe dwellings - a case study at the great Hungarian plain.

    Science.gov (United States)

    Szabó, Zsuzsanna; Jordan, Gyozo; Szabó, Csaba; Horváth, Ákos; Holm, Óskar; Kocsy, Gábor; Csige, István; Szabó, Péter; Homoki, Zsolt

    2014-06-01

    Radon and thoron isotopes are responsible for approximately half of the average annual effective dose to humans. Although the half-life of thoron is short, it can potentially enter indoor air from adobe walls. Adobe was a traditional construction material in the Great Hungarian Plain. Its major raw materials are the alluvial sediments of the area. Here, seasonal radon and thoron activity concentrations were measured in 53 adobe dwellings in 7 settlements by pairs of etched track detectors. The results show that the annual average radon and thoron activity concentrations are elevated in these dwellings and that the proportions with values higher than 300 Bq m(-3) are 14-17 and 29-32% for radon and thoron, respectively. The calculated radon inhalation dose is significantly higher than the world average value, exceeding 10 mSv y(-1) in 7% of the dwellings of this study. Thoron also can be a significant contributor to the inhalation dose with about 30% in the total inhalation dose. The changes of weather conditions seem to be more relevant in the variation of measurement results than the differences in the local sedimentary geology. Still, the highest values were detected on clay. Through the year, radon follows the average temperature changes and is affected by the ventilation, whereas thoron rather seems to follow the amount of precipitation.

  19. Study of the background of the neutrinoless double {beta} decay with the detector NEMO 2: contribution arising from the radon diffusion and internal pollution of the source {sup 214}Bi have been estimated; Etude du bruit de fond de la double-desintegration {beta} sans emission de neutrino dans le detecteur NEMO 2: contribution du radon ambiant et mesure de la pollution interne de la source en {sup 214}Bi

    Energy Technology Data Exchange (ETDEWEB)

    Mauger, F.

    1995-02-01

    The NEMO experiment is designed to understand the nature of the neutrino by studying the double beta decay of Mo-100 which is related to the Majorana neutrino effective mass. In this kind of experiment a good understanding of the different sources of background is crucial as only few events are expected per year at the required level of sensitivity. In this thesis we present the main theoretical and experimental aspects of the measurement of the neutrinoless double beta decay of Mo-100 with the prototype detector NEMO2. The goal of this study is to obtain a realistic interpretation of the few events detected at high energy in the two-electron channel as a background to neutrinoless double beta decay. In particular, the contribution arising from Bi-214 has been investigated. These events have been selected and analysed by means of the beta-alpha decays of Bi-214 into Pb-210. The events are characterized by a delayed track in the wire chamber and the corresponding signal is rather clean. The study has demonstrated the diffusion of Rn-222 into the detector and its contribution to Bi-214 pollution has been estimated. A measurement of the Bi-214 internal contamination of the source has been made as well as an estimation of the Bi-214 deposit due to Rn-222. As a result of this study it appears that, under the conditions of the NEMO2 experiment, the Bi and Rn contributions are of the same order of magnitude as the background induced at high energy by two-neutrino double beta decay. In conclusion, the backgrounds of the neutrinoless double beta decay of Mo-100 are well understood in the NEMO2 experiment leading to an extrapolation for the NEMO3 experiment. (authors).

  20. Preliminary Study for 3D Radon Distribution Modelling in the Room

    Energy Technology Data Exchange (ETDEWEB)

    Lee, ChoongWie; Kim, HeeReyoung [UNIST, Ulsan (Korea, Republic of)

    2016-10-15

    Radon exists in the form of noble gas, which comes from decay of {sup 238}U, becoming stable {sup 206}Pb going through 4 alpha and 4 beta decays. If this process occurred in human body after inhalation, lung could be damaged by interaction with these radiations causing lung cancer. Most radon in indoor air comes from soil (85 - 97%) through crack of the wall but it also came from wall (2 - 5%) itself in home. Due to its hazardous and unpredictable characteristic, radon became one of the concerning nuclides in indoor air. Hence, the number of survey and research about radon has been increased. Although accurate radon measurement is important to evaluate health risk, it is hard to actually achieve because radon is affected by many conditions, where its concentration can vary easily. Moreover, radon concentration can vary according to the height because of density of radon in the spatial aspect. 3D distribution modelling in the room of radon with aerodynamic features and sources variations was carried out to find average and maximum radon concentration. 3D radon distribution in the room would be find through this computational analysis and it is thought to be possible to correct measured radon concentration with spatial variation to fit the height of nose where inhalation occur. The methodological concept for 3D modelling was set up to solve transport equation for radon behavior by using computational fluid dynamics (CFD) software such as FLUENT.

  1. Radon and Lung Cancer Case-Control Study in Middle Ural

    International Nuclear Information System (INIS)

    Kirdin, I.A.; Lezhnin, V.L.; Yarmoshenko, I.V.; Ekidin, A.

    2001-01-01

    Full text: The pilot phase of radon and lung cancer case-control study has been performed in Karpinsk and Pervouralsk towns of Middle Ural region of Russia. The case group consists of 341 persons with lung cancer and living in that towns at least five previous years. The lung cancer diagnoses were carefully verified by instrumental techniques and 70% of its were morphologically validated. The persons for the control group (448) were chosen from the population living in that towns at least five years taking into account the age and sex. The special epidemiological questionnaire was developed which includes the items by the groups of factors as follow: clinical data, social factors, chronic lung diseases, life habit, tobacco smoking, alcohol drinking, diet preference etc. The epidemiological questionnaires were fulfilled for each member of case and control groups. Radon gas concentration and thoron equilibrium equivalent concentration measurements had been performed using nuclear track detectors and grab sampling accordingly in the dwellings of case and control groups members. By preliminary estimation the odds ratios are 1, 0.91, 1.2, 1.1 in the ranges of radon and thoron equilibrium equivalent concentration 0-6, 3-13, 13-36 and 36-370 Bq/m 3 respectively. The deeper and more rigorous analysis as well as different independent approaches will be discussed in the paper.(author)

  2. Design, characterization and use of replicate human upper airways for radon dosimetry studies

    International Nuclear Information System (INIS)

    Swift, D.L.; Cheng, Y.S.; Su, Y.F.; Yeh, H.C.

    1992-01-01

    The size distribution of inhaled radon progeny aerosols is a significant factor in dosimetry. The role of the airways above the trachea is an important determinant of the respiratory distribution of both attached and unattached progeny aerosols. In order to provide information on the effect of particle size and breathing conditions on the overall and local deposition, we have developed a method to produce a replicate airway model from an in vivo magnetic resonance imaging coronal scan. The model consists of a sandwich of methacrylate elements, each element having the thickness of the scan interval. The transition between successive scan outlines traced on the front and back surfaces of each element is handsculpted in the plastic. The hollow model of the nasal passages thus produced has been characterized both morphologically and fluid-mechanically and has a flow resistance typical of a normal adult. The model has several distinct advantages for studies of radon progeny aerosol deposition. After exposure to a radioaerosol (or to an aerosol of an otherwise measurable substance) the individual elements can be separated to determine local deposition. The dimensions of specific upper-airway regions can be changed by replacing a small number of elements. The model has been incorporated in an exposure system for determining overall nandregional deposition of aerosols whose median diameter is approximately 1.7 nm. Measurements at several flow rates are presented to demonstrate use of the model in radon dosimetry. The model should also be useful for determining the airway deposition of other environmental aerosols

  3. Indoor radon and radon daughters survey at Campinas-Brazil using CR-39: First results

    International Nuclear Information System (INIS)

    Guedes, S.; Hadler, J.C.N.; Iunes, P.J.; Navia, L.M.S.; Neman, R.S.; Paulo, S.R.; Rodrigues, V.C.; Souza, W.F.; Tello, C.A.S.; Zuniga, A.

    1999-01-01

    The first results of a radon and radon daughters (RD) survey performed at Campinas-SP, Brazil, are presented. We employed a technique that, potentially, makes possible to measure the radon and RD activity in the air and to separate from this result the activity of radon, alone. In this preliminary paper only the former activity is studied

  4. Indoor radon and radon daughters survey at Campinas-Brazil using CR-39: First results

    CERN Document Server

    Guedes, S; Iunes, P J; Navia, L M S; Neman, R S; Paulo, S R; Rodrigues, V C; Souza, W F; Tello, C A S; Zúñiga, A G

    1999-01-01

    The first results of a radon and radon daughters (RD) survey performed at Campinas-SP, Brazil, are presented. We employed a technique that, potentially, makes possible to measure the radon and RD activity in the air and to separate from this result the activity of radon, alone. In this preliminary paper only the former activity is studied.

  5. Sign of Radon for locate geothermic sources

    International Nuclear Information System (INIS)

    Gonzalez Teran, D.

    1991-01-01

    Evaluation of a geothermic field is based upon geological, geophysical and geochemical studies that enable the evaluation of the deposit potential, that is to say, the amount of energy per unit mass, the volume of the trapped fluid, vapor fraction and fluid chemistry. This thesis has as its objective the evaluation of radon gas emanation in high potential geothermic zones in order to utilize the results as a low cost and easy to manage complimentary tool in geothermic source prospection. In chapter I the importance and evaluation of a geothermic deposit is discussed. In chapter II the general characteristics of radon are discussed: its radioactivity and behavior upon diffusion over the earth's surface> Chapter III establishes the approach used in the geothermic field of Los Azufres, Michoacan, to carry out samplings of radon and the laboratory techniques that were used to evaluate the concentration of radon in the subsoil. Finally in chapter IV measurements of radon in the field are compared to geological faults in the area under study. The sampling zones were: low geothermic potential zone of the northern and the southern zone having a greater geothermic potential than that in the north. The study was carried out at different sampling times using plastics detectors of from 30 to 46 days from February to July. From the results obtained we concluded that the emission of radon was greater in the zones of greatest geothermic potential than in the low geothermic potential zones it was also affected by the fault structure and the time of year in which sampling was done. (Author)

  6. The radon

    International Nuclear Information System (INIS)

    1998-01-01

    This booklet is intended to answer briefly the most important questions about the nature and sources of radon, its pathways from environment to organism, as well as the ways to minimize its concentration in the habitat's atmosphere. The radon is a naturally appearing radioactive gas, produced through the decay of uranium and radium present in the terrestrial crust. It can be found everywhere on the planet's surface and it is emitted particularly from the granite and volcanic underground rocks as well as from certain construction materials. It is one of the agents producing pulmonary cancer, although not so dangerous as the tobacco is. The following items are elaborated in this booklet: - the place of radon in the average exposure to ionizing radiations of the French population; - the risk; - the radon in the environment (the meteorological conditions, the nature of the rocks); - radon in dwellings (radon measurements in the French dwellings, the entrance pathways of radon, the dependence of radon concentration on the profession and way of life of the inhabitants); - radon measurements; - how to reduce the radon concentration in dwellings

  7. Radon in public buildings

    International Nuclear Information System (INIS)

    Schulz, H.; Flesch, K.; Hermann, E.; Loebner, W.; Leissring, B.

    2009-01-01

    From the Free State of Saxony, a study was commissioned to survey how reliable measurements to characterize the radon situation in public buildings at a reasonable financial and human effort can be carried out to reduce radiation exposure in public buildings. The study approach was for 6 objects. To characterize the radon situation the time evolution measurement of radon concentrations of more than 1 to 2 weeks turned out to be sufficient. A novel data analysis enables the identification of a ''typical daily alteration of the radon concentration'' depending on the ventilation conditions and the daily use of the offices or class rooms. The identification of typical diurnal radon variations for the working time and weekends or holidays is of fundamental importance for assessing the exposure situation in public buildings. It was shown that the radon concentration during working time are in general much lower than in the times when the buildings (offices) are unused. It turned out that the long-term radon measurements with nuclear track detectors within distinct time regimes (day / night, working hours / leisure time) by utilizing switch modules are very efficient to estimate the actual exposure. (orig.)

  8. Assessment of radon build up pattern in a closed room with minimal ventilation disturbance

    International Nuclear Information System (INIS)

    Singh, M.K.; Patnaik, R.L.; Jha, V.N.; Ravi, P.M.; Tripathi, R.M.

    2016-01-01

    Radon is ubiquitous in nature. The immediate source of Radon is 226 Ra is present in building materials underneath earth due to presence of natural uranium in terrestrial region. 222 Ra gas continuously diffused out into room atmosphere through the pores, cracks and fissures if any. The buildup of this 222 Rn is anticipated in a closed room lack of proper ventilation. A study was done to see the build up pattern of radon concentration by two different measurement techniques in a closed room of ESL, Jaduguda. Present paper summarizes the result of buildup study of 222 Rn in a closed room of lab for a period of 3 months

  9. Radon thematic days - Conference proceedings

    International Nuclear Information System (INIS)

    2011-03-01

    This document brings together the available presentations given at the Radon thematic days organized by the French society of radiation protection (SFRP). Twenty five presentations (slides) are compiled in the document and deal with: 1 - General introduction about radon (Sebastien Baechler, IRA); 2 - Survey of epidemiological studies (Dominique Laurier, IRSN); 3 - Dosimetric model (Eric Blanchardon, Estelle Davesne, IRSN); 4 - Radon issue in Franche-Comte: measurement of the domestic exposure and evaluation of the associated health impact (Francois Clinard, InVS); 5 - WHO's (World Health Organization) viewpoint in limiting radon exposure in homes (Ferid Shannoun, OMS); 6 - Radon measurement techniques (Roselyne Ameon, IRSN); 7 - Quality of radon measurements (Francois Bochud, IRA); 8 - International recommendations (Jean-Francois Lecomte, IRSN); 9 - Radon management strategy in Switzerland - 1994-2014 (Christophe Murith, OFSP); 10 - 2011-2015 action plan for radon risk management (Jean-Luc Godet, Eric Dechaux, ASN); 11 - Radon at work place in Switzerland (Lisa Pedrazzi, SUVA); 12 - Strategies of radiation protection optimization in radon exposure situations (Cynthia Reaud, CEPN); 13 - Mapping of the radon potential of geologic formations in France (Geraldine Ielsch, IRSN); 14 - Radon database in Switzerland (Martha Gruson, OFSP); 15 - Radon 222 in taps water (Jeanne Loyen, IRSN); 16 - Buildings protection methods (Bernard Collignan, CSTB, Roselyne Ameon, IRSN); 17 - Preventive and sanitation measures in Switzerland (Claudio Valsangiacomo, SUPSI); 18 - Training and support approach for building specialists (Joelle Goyette-Pernot, Fribourg engineers and architects' school); 19 - Status of radon bulk activity measurements performed between 2005-2010 in public areas (Cyril Pineau, ASN); 20 - Neuchatel Canton experiments (Didier Racine, SENE); 21 - Montbeliard region experience in the radon risk management (Isabelle Netillard, Pays de Montbeliard Agglomeration); 22

  10. Characterisation of non-aerosol-bound fractions of radon decay products under environmental conditions

    International Nuclear Information System (INIS)

    Pagelkopf, P.; Porstendoerfer, J.

    2004-01-01

    Dose-relevant factors such as the concentration and size distribution of radon decay products are strongly influenced by the charge-carrying fraction and state of charge of the first radon decay product, 2 18Po. The charge of 2 18Po influences its own mobility and hence its attachment to aerosols and deposition on surfaces, also referred to as ''plating out''. The mobility of 2 18Po can be described in terms of its diffusion coefficient. The goal of the present study was to determine theoretically as well as practically the charge-carrying fraction of radon decay products 2 18Po and 2 14Pb under room air conditions and to design and construct an electrical mobility spectrometer. The spatial model developed by Jacobi and modified by Porstendoerfer for calculating the concentration of unattached radon decay products in indoor and outdoor air under steady-state conditions was extended to permit a differentiated description of the charge-carrying and neutral unattached fractions of radon decay products 2 18Po and 2 14Pb. An 8 m 2 chamber permitting chamber air control in terms of radon gas concentration and humidity was built in order to study the behaviour of radon decay products. The charge-carrying fraction of unattached radon decay products 218 Po and 214 Pb was measured in this chamber. A technique referred to as the online backscreen technique (OBST) was developed to permit the continuous measurement of unattached decay products. The technique involves the diffusive deposition of unattached radon decay products from a laminar flow onto a wire lattice and their subsequent measurement. The total fraction of decay products is then determined by means of the filtration method. Furthermore, all parameters required for modelling such as radon gas, decay product and aerosol concentrations as well as air humidity, temperature and ion dose rate were measured [de

  11. Contribution of radon and radon daughters to respiratory cancer

    International Nuclear Information System (INIS)

    Harley, N.; Samet, J.M.; Cross, F.T.; Hess, T.; Muller, J.; Thomas, D.

    1986-01-01

    This article reviews studies on the contribution of radon and radon daughters to respiratory cancer and proposes recommendations for further research, particularly a national radon survey. The steady-state outdoor radon concentration averages 200 pCi/m3, and indoor levels are about 4 times higher. The primary source of radon in homes is the underlying soil; entry depends on multiple variables and reduced ventilation for energy conservation increases indoor radon levels. Occupational exposures are expressed in units of radon daughter potential energy concentration or working level (WL). Cumulative exposure is the product of the working level and the time exposed. The unit for cumulative exposure is the working level month (WLM). The occupational standard for radon exposure is 4 WLM/year, and 2 WLM/year has been suggested as a guideline for remedial action in homes. Epidemiologic studies show that miners with cumulative radon daughter exposures somewhat below 100 WLM have excess lung cancer mortality. Some 3% to 8% of miners studied have developed lung cancer attributable to radon daughters. All of the underground mining studies show an increased risk of lung cancer with radon daughter exposure. All cell types of lung cancer increased with radon exposure. If radon and smoking act in a multiplicative manner, then the risk for smokers could be 10 times that for nonsmokers. The potential risk of lung cancer appears to be between 1 and 2 per 10,000/WLM, which yields a significant number of lung cancers as some 220 million persons in the United States are exposed on average to 10 to 20 WLM/lifetime

  12. Case-control study on radon exposure and lung cancer in an Italian region. Preliminary results

    International Nuclear Information System (INIS)

    Bochicchio, F; Nuccetelli, C.; Forastiere, F.; Mallone, S.; Sera, F.

    2000-01-01

    The present estimates of the lung cancer risk for the general population due to radon exposure in dwellings are generally obtained by extrapolating the risk estimates derived from epidemiologic studies on miner cohorts. However, due to uncertainties related to this extrapolation, numerous case-control studies in Europe and North America were planned to estimate directly the risk in dwellings. Most of these studies are still underway and, thanks to their similar design and compatible protocols, it will be possible to perform a pooled analysis in order to improve statistical power. One of these projects is being conducted in the Lazio region of Italy, which is one of the Italian regions with the highest levels of radon indoors. A total of 408 cases and 424 controls older than 34 years, who lived for 25 years or longer in the Lazio Region, were recruited in a hospital of Rome. Detailed information regarding smoking, and occupational exposure of the subjects were collected by interviews in hospital. Residential histories (periods and addresses) during the 35 years preceding the enrolment were ascertained for all study members from the local Register and from a short questionnaire to the subjects or to the next-of-kin, resulting in 2068 dwellings to be monitored within the Lazio region. The distribution of the number of dwellings among cases and controls was the following: 25.7% of the cases and 27.3% of the controls had lived all the preceding 35 years in a single dwelling, whereas only a minority (7.9%) changed five addresses or more. The mean number of dwellings was very similar among cases (2.47) and controls (2.50). In each dwelling, radon dosemeters were placed in both the main bedroom and living room for two consecutive six-month periods. In the second six-month period, two thermoluminescent dosemeters were also collocated in each monitored room to measure gamma radiation emitted by the building materials, in order to evaluate more comprehensively the exposure of

  13. Measurement of radon concentration in Taiz city dwellings-yemen

    International Nuclear Information System (INIS)

    Ali, Taher M.; Ahmed, Hayel A.; Ismail, Rokhsana M.

    2001-01-01

    Radon gas considered being a high part of natural radiation background. Emitting alpha particles; radon daughters may be deposited into the lungs and cause health hazards. For this reason, estimation of radon levels in dwellings was done in many countries. In our country, Radon group in the Department of physics, University of Aden has been studied radon level in Aden dwelling. The present study is about the radon level in Taiz City - Yemen. Passive diffusion dosimeters containing (SSNTD s ) Cr - 39 detectors were used in the present work. 125 dosimeters were distributed into dwellings of ten regions in Taiz City. Results obtained show that Rn 222 levels vary between 4 Bq/m 3 and 99 Bq/m 3 . The average concentration in Al-Hasseb district is 23 Bq/m 3 and in Algumhuri hospital district is 53 Bq/m 3 . In other regions it varies between the two values. Whereas the general average in the Taiz City is 34 Bq/m 3 . (author)

  14. Study of the effects of atmospheric parameters on ground radon concentration by track technique

    International Nuclear Information System (INIS)

    Tidjani, Adams

    1988-01-01

    Radon emanation was continuously monitored for 24 months, accompanied by measurements of atmospheric parameters. Integrated measurments of radon concentrations have been performed with LR-115 cellulose nitrate track detectors. The monitoring was conducted at 16 sites distributed around the Dakar University area. Observed changes in radon concentration are interpreted as being caused by changes in meteorological conditions and ocean tides. (author)

  15. Failure of preventive measures against radon penetration from the ground in a new-built family house - a case study

    International Nuclear Information System (INIS)

    Neznal, M.; Neznal, M.; Jiranek, M.; Fronka, A.

    2006-01-01

    A system of preventive protection of houses against radon penetration from the ground [1] has been in operation for more than 15 years in the Czech Republic. The determination of a so-called radon index of the building site represents the first step. The assessment is based on measurements of soil gas radon concentration and on the determination of soil permeability. During the years, the method was modified several times, especially the recommendation dealing with the classification of soil permeability, but the base remains stable: The soil characteristics are measured in-situ and protective measures are designed with respect to the measured properties of the soil and to the dwelling design. The site-specific, individual approach should enable to propose an optimal preventive strategy corresponding to local conditions. If the radon index is other than low (i.e. medium, or high), the building must be protected against radon in accordance with the Czech Atomic Law. Protective measures should be designed and installed according to the Czech National Standard [2]. Basic principles of the protection can be summarized in the following way: If the radon index of a building site is low, no special provisions are required. Normal damp-proofing that is designed in accordance with hydro-geological conditions provides sufficient building protection. Nevertheless, the insulation has to be installed over the whole ground area of the building. It is also recommended that the corridor with stairs leading from the underground floor to the upper floors should be separated by the door. In case of medium radon index of a building site, each high-quality and long life damp-proofing, with the measured radon diffusion coefficient, may be considered as radon-proof insulation in compliance with C.S.N. 73 06 01. A required insulation thickness is calculated using the known value of radon diffusion coefficient. The insulation must be laid down continuously on the whole area of the

  16. Lung Cancer Risk from Occupational and Environmental Radon and Role of Smoking in Two Czech Nested Case-Control Studies

    Directory of Open Access Journals (Sweden)

    Ladislav Tomasek

    2013-03-01

    Full Text Available The aim of the present study was to evaluate the risk of lung cancer from combined exposure to radon and smoking. Methodologically, it is based on case-control studies nested within two Czech cohort studies of nearly 11,000 miners followed-up for mortality in 1952–2010 and nearly 12,000 inhabitants exposed to high levels of radon in homes, with mortality follow-up in 1960–2010. In addition to recorded radon exposure, these studies use information on smoking collected from the subjects or their relatives. A total of 1,029 and 370 cases with smoking information have been observed in the occupational and environmental (residential studies, respectively. Three or four control subjects have been individually matched to cases according to sex, year of birth, and age. The combined effect from radon and smoking is analyzed in terms of geometric mixture models of which the additive and multiplicative models are special cases. The resulting models are relatively close to the additive interaction (mixing parameter 0.2 and 0.3 in the occupational and residential studies, respectively. The impact of the resulting model in the residential radon study is illustrated by estimates of lifetime risk in hypothetical populations of smokers and non-smokers. In comparison to the multiplicative risk model, the lifetime risk from the best geometric mixture model is considerably higher, particularly in the non-smoking population.

  17. Radon transport modelling: User's guide to RnMod3d

    DEFF Research Database (Denmark)

    Andersen, Claus Erik

    2000-01-01

    RnMod3d is a numerical computer model of soil-gas and radon transport in porous media. It can be used, for example, to study radon entry from soil into houses in response to indoor-outdoor pressure differences or changes in atmospheric pressure. It canalso be used for flux calculations of radon...... decay, diffusion and advection of radon can be solved. Moisture is included in the model, and partitioning ofradon between air, water and soil grains (adsorption) is taken into account. Most parameters can change in time and space, and transport parameters (diffusivity and permeability) may...... be anisotropic. This guide includes benchmark tests based on simpleproblems with known solutions. RnMod3d has also been part of an international model intercomparison exercise based on more complicated problems without known solutions. All tests show that RnMod3d gives results of good quality....

  18. Determination of radon and thoron permeability through some plastics by track technique

    Energy Technology Data Exchange (ETDEWEB)

    Hafez, A.-F.; Somogyi, G.

    1986-01-01

    Experiments have been performed to study the usefulness of several types of plastic foils as filter to separate radon and thoron. Time-integrated alpha-activity measurements have been carried out by using the so-called ''can-technique'' equipped with both LR-115 and CR-39 track detectors. The track density observed on the detectors, taken as a measure of radon activity concentration, has been determined as a function of the thickness of filter foils. The radon permeability and the thoron separation factors have been determined. It is shown that various plastic foils exhibit considerable differences in radon diffusion coefficient owing to their different chemical structures. Among the plastic foils investigated the polyethylene proved to have the highest gas diffusion coefficient.

  19. A calibration facility for radon fluxmeter

    International Nuclear Information System (INIS)

    Li Xianjie; Qiu Shoukang; Zhou Jianliang; Liu Chunkui; Pan Jialin; Yang Mingli

    1998-01-01

    Calibration facilities for radon fluxmeter with three kinds of different emanation medium have been developed. The stability of radon flux is 5%, 9% (RSD) respectively. The uniformity of radon flux is 4.5%, 8.5% (RSD) respectively. These specifications fulfill the calibration requirement for radon fluxmeter. The determination of radon flux of facility takes full account of eliminating the main error source-attenuation effect (including leakage and back diffusion etc.): not only prevent attenuation and make a relevant correction. Therefore the accuracy of determination is assured. The calibration, intercomparison of radon flux meter and the quantitatively evaluation on the measurement method of radon flux are made to be possible by the successful establishment of this facility. (author)

  20. Animal study on biological responses by radon inhalation making use of waste rock which contains feeble activity of uranium (2) (Joint research)

    International Nuclear Information System (INIS)

    Ishimori, Yuu; Sakoda, Akihiro; Tanaka, Hiroshi; Mitsunobu, Fumihiro; Yamaoka, Kiyonori; Kataoka, Takahiro; Etani, Reo

    2016-03-01

    Okayama University and the Japan Atomic Energy Agency (JAEA) have carried out the collaborative study of physiological effects of inhaled radon for the low-dose range. Main assignments were as follows. Based on the clinical knowledge, Misasa Medical Center (Okayama University Hospital) clarified the issues that should be addressed. Graduate School of Health Sciences (Okayama University) supervised the research and studied the biological responses. The JAEA made the development and control of a facility for radon inhalation experiments and the investigation of biokinetics and exposure doses of radon. From 2009 to 2013, the following results were obtained. (1) Literature on drinking effects of radon hot spring water was surveyed to determine the present tasks. (2) Under the present experimental conditions, drinking of hot spring water into which radon was intentionally introduced using the equipment in the facility did not have significant effects on mice. (3) Inhibitory effects of antioxidant pre-supplements (Vitamins C and E) and radon pre-inhalation on hepatic or renal oxidative damage were examined to make the comparison. (4) In order to discuss biological responses quantitatively following radon inhalation, the biokinetics of inhaled radon were studied. (5) Some exposure routes due to inhalation of radon or its progeny were modeled to calculate organ doses in mice. (author)

  1. Radon -- an environmental hazard

    International Nuclear Information System (INIS)

    Faheem, M.; Rahman, R.; Rahman, S.; Matiullah

    2005-01-01

    Humans have always been exposed throughout its period of experience to naturally occurring sources of ionizing radiation or natural background radiation, It is an established fact that even these low background doses are harmful to man and cause increased cancer risk. About half of our radiation comes from radon, a radioactive gas coming from normal materials in the ground. Several building materials such as granite, bricks, sand, cement etc., contain uranium in various amounts. The radioactive gas /sup 222/Rn produced in these materials due to decay of 226Ra is transported to indoor air through diffusion and convective flow. It seeps out of soil and rocks, well water, building materials and other sources at a varied rate. Amongst the naturally occurring radioisotopes, radon is the most harmful one that can be a cause of lung cancer. Radon isotopes are born by the decay of radium and radium production in turns comes from uranium or thorium decay. For humans the greatest importance among Radon isotopes is attributed to /sup 222/Rn because it is the longest lived of the three naturally produced isotopes. Drinking water also poses a threat. Radon gas is dissolved in water and is released into the air via water faucets, showerheads, etc. the lack of understanding has so far lead to speculative estimates of pollutant related health hazards. (author)

  2. The Assessment of the Integrated Antioxidant System of the Body in the Course of Radon Therapy: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Jadwiga Kuciel-Lewandowska

    2018-01-01

    Full Text Available Introduction. The sources of Reactive Oxidative Species (ROS in the organism are the respiratory processes occurring in cells catalyzed by different enzymes. Operation of ROS is balanced by antioxidants, the compounds; although present in low concentrations, they significantly inhibit the degree of oxidation of particular molecules. The Aim of the Study. The aim of this study was to assess the changes in the integrated antioxidant system under the influence of radon therapy in osteoarthritis patients. Material and Methods. Observation included 35 patients suffering from degenerative joints and disc disease (mean age 56.5 years undergoing radon water therapy and control group that consisted of 15 osteoarthritis patients (mean age 54.2 without contact with radon water. Before therapy and after 18 days of treatment, serum total antioxidant status (TAS was assessed with the use of standard colorimetric assay. Results. In the study group, we observed trends to increase TAS concentration, whereas, in the control group, TAS concentration was decreasing. Conclusions. (1 Radon waters treatment influenced the level of TAS of osteoarthritis patients treated with the radon water. (2 The change in TAS concentrations in the study group may be the result of low doses of ionizing radiation, but further studies on larger patient’s groups are demanded. This study is registered with number NCT03274128.

  3. An Organizational Diffusion Study on Distance Education

    Science.gov (United States)

    Smith, Lillian Upton; Richter, Donna L.; Miner, Kathleen R.; Watkins, Ken; Usdan, Stuart

    2005-01-01

    This research explored the diffusion process of distance education in schools of public health to determine best practices in the planning and implementation of future programs. The researcher traced the diffusion process by utilizing a multiple-case study methodology using a semi-structured interview to collect the perceptions of Distance…

  4. Study on singular radon releases from mining residues and the impact on the outdoor radon concentration; Untersuchungen zu singulaeren Radonfreisetzungen aus bergbaulichen Hinterlassenschaften und ihre Auswirkungen auf die Radonkonzentration im Freien

    Energy Technology Data Exchange (ETDEWEB)

    Kahnt, Rene; Martin, Mirko; Pinka, Jana

    2012-03-15

    The G.E.O.S. mbH was assigned by the Bundesamt fuer Strahlenschutz to perform time resolved measurements of the radon release and time and spatial resolved studies on the atmospheric dispersion dependent on the topographic and meteorological conditions in the area of Haiden. The report includes data on the radon release from mining residues at the site Johanngeorgenstadt and measurements in other areas.

  5. Study of properties of active charcoal used for measuring of low radon activities

    International Nuclear Information System (INIS)

    Muellerova, M.; Holy, K.

    2011-01-01

    We used the German charcoal Silicarbon for adsorption of radon from the air. From the column with activated carbon arranged in a row, we obtain cut-off dependence of radon on activated carbon at various temperatures, cooling and also at different speeds, drawing radon air through activated charcoal. From information we have chosen the most appropriate combination of temperature and cooling flow in order to maximize capture efficiency of radon in the first column of active charcoal. To change active carbon and optimization of operation allows us to measure the radon exhalation rate from various materials up to the level of 3·10 -9 Bq/s. (authors)

  6. Radon risk communication research: Practical lessons

    International Nuclear Information System (INIS)

    Fisher, A.; Johnson, F.R.

    1990-01-01

    Those responsible for state and local radon programs often express frustration about the small share of homes that have been tested for radon, and the small share of those with high readings that have been mitigated. There are now a number of completed studies that have examined how well alternative ways of communicating about radon risk have accomplished the goals of motivating appropriate testing and mitigation. This paper summarizes the research results that are most crucial for planning and implementing effective radon risk communication programs. We identify six reasons why people do not respond to radon as a serious threat and provide some remedies suggested by radon studies

  7. The Montana Radon Study: Social Marketing via Digital Signage Technology for Reaching Families in the Waiting Room

    Science.gov (United States)

    2015-01-01

    Objectives. I tested a social marketing intervention delivered in health department waiting rooms via digital signage technology for increasing radon program participation among priority groups. Methods. I conducted a tri-county, community-based study over a 3-year period (2010–2013) in a high-radon state by using a quasi-experimental design. We collected survey data for eligible participants at the time of radon test kit purchase. Results. Radon program participation increased at the intervention site (t38 = 3.74; P = .001; 95% confidence interval [CI] = 4.8, 16.0) with an increase in renters (χ21,228 = 4.3; P = .039), Special Supplementary Nutrition Program for Women, Infants, and Children families (χ21,166 = 3.13; P = .077) and first-time testers (χ21,228 = 10.93; P = .001). Approximately one third (30.3%; n = 30) attributed participation in the radon program to viewing the intervention message. The intervention crossover was also successful with increased monthly kit sales (t37 = 2.69; P = .01; 95% CI = 1.20, 8.47) and increased households participating (t23 = 4.76; P marketing message was an effective population-based intervention for increasing radon program participation. The results prompted policy changes for Montana radon programming and adoption of digital signage technology by 2 health departments. PMID:25121816

  8. Error in measuring radon in soil gas by means of passive detectors

    International Nuclear Information System (INIS)

    Tanner, A.B.

    1991-01-01

    Passive detection of radon isotopes depends on diffusion of radon atoms from the sites of their generation to the location of the detecting or collecting device. Because some radon decays en route to a passive detector in soil, the radon concentration measured by the detector must be less than the concentration in those soil pores where it is undiminished by diffusion to the detector cavity. The true radon concentration may be significantly underestimated in moist soils. (author)

  9. The radon 222 transport in soils. The case of the storage of residues coming from uranium ores processing; La migration du radon 222 dans un sol. Application aux stockages de residus issus du traitement des minerais d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, C

    2000-07-01

    Uranium Mill Tailings (UMT) contain comparatively large quantities of radium-226. This radionuclide yields, by radioactive decay, the radioactive gas radon-222. Tailing piles are routinely covered to reduce the radon release-rate into the atmosphere. In order to assess the long term environmental impact of a UMT repository, mechanisms governing radon exhalation at the soil surface must be deciphered and understood. A model of radon transport in the unsaturated zone is developed for this purpose: water- and air-flow in the porous material are determined, as well as radon transport by diffusion in the pore space and advection by the gas phase. The radon transport model in the unsaturated zone - TRACI (which stands, in French, for Radon Transport within the Unsaturated Layer) - calculates moisture contents in the soil, Darcy's velocities of the liquid and gas phases, radon concentrations in the gas phase and radon flux at the soil surface. TRACI's results are compared with observations carried out on a UMT and a cover layer. Input parameters are derived from the textural analysis of the material under study, whereas upper boundary conditions are given by meteorological data. If we consider measurement errors and uncertainties on the porous medium characterisation, model's results are generally in good agreement with observations, at least on the long run. Moreover, data analysis shows hat transient phenomena are understood as well, in most situations. (author)

  10. A feasibility study of geogenic indoor radon mapping from airborne radiometric survey in northern Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Wattananikorn, K. [Department of Physics, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)], E-mail: kittic@science.cmu.ac.th; Emharuthai, S. [Department of Physics, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Wanaphongse, P. [Office of Atoms for Peace, Bangkok (Thailand)

    2008-01-15

    Experiments were carried out in seven test sites on three Quaternary alluvial and terrace deposit basins of northern Thailand, to test the possibility of using airborne equivalent uranium to predict geogenic indoor radon values of the region. The methodology was based on the correlation among soil gas permeability, soil radon concentration and indoor radon, as well as a relationship between soil radon and airborne uranium values. The methodology established works rather well when tested in areas of known indoor radon. Based on the predicted values that were obtained from this method, indoor radon in most areas of alluvial and terrace deposit basins of northern Thailand is less than 44Bq/m{sup 3}. There is no area in these basins where predicted indoor radon exceeds 74Bq/m{sup 3}.

  11. Radon exposure and lung cancer

    International Nuclear Information System (INIS)

    Planinic, J.; Vukovic, B.; Faj, Z.; Radolic, V.; Suveljak, B.

    2003-01-01

    Although studies of radon exposure have established that Rn decay products are a cause of lung cancer among miners, the lung cancer risk to the general population from indoor radon remains unclear and controversial. Our epidemiological investigation of indoor radon influence on lung cancer incidence was carried out for 201 patients from the Osijek town. Ecological method was applied by using the town map with square fields of 1 km 2 and the town was divided into 24 fields. Multiple regression study for the lung cancer rate on field, average indoor radon exposure and smoking showed a positive linear double regression for the mentioned variables. Case-control study showed that patients, diseased of lung cancer, dwelt in homes with significantly higher radon concentrations, by comparison to the average indoor radon level of control sample. (author)

  12. A model to predict radon exhalation from walls to indoor air based on the exhalation from building material samples

    International Nuclear Information System (INIS)

    Sahoo, B.K.; Sapra, B.K.; Gaware, J.J.; Kanse, S.D.; Mayya, Y.S.

    2011-01-01

    In recognition of the fact that building materials are an important source of indoor radon, second only to soil, surface radon exhalation fluxes have been extensively measured from the samples of these materials. Based on this flux data, several researchers have attempted to predict the inhalation dose attributable to radon emitted from walls and ceilings made up of these materials. However, an important aspect not considered in this methodology is the enhancement of the radon flux from the wall or the ceiling constructed using the same building material. This enhancement occurs mainly because of the change in the radon diffusion process from the former to the latter configuration. To predict the true radon flux from the wall based on the flux data of building material samples, we now propose a semi-empirical model involving radon diffusion length and the physical dimensions of the samples as well as wall thickness as other input parameters. This model has been established by statistically fitting the ratio of the solution to radon diffusion equations for the cases of three-dimensional cuboidal shaped building materials (such as brick, concrete block) and one dimensional wall system to a simple mathematical function. The model predictions have been validated against the measurements made at a new construction site. This model provides an alternative tool (substitute to conventional 1-D model) to estimate radon flux from a wall without relying on 226 Ra content, radon emanation factor and bulk density of the samples. Moreover, it may be very useful in the context of developing building codes for radon regulation in new buildings. - Research highlights: → A model is proposed to predict radon flux from wall using flux of building material. → It is established based on the diffusion mechanism in building material and wall. → Study showed a large difference in radon flux from building material and wall. → Model has been validated against the measurements made at

  13. Radon, smoking and human papilloma virus as risk factors for lung cancer in an environmental epidemiological study

    Directory of Open Access Journals (Sweden)

    G. P. Malinovsky

    2017-01-01

    Full Text Available The aim of the study: to analyze the risk of lung cancer caused by exposure to indoor radon using an environmental study, taking into account recent data on the possible effect of Human Papillomavirus, based on lung cancer mortality and radon exposure in the Russian regions.Materials and methods: in the analysis, linear dependencies of lung cancer against influencing factors were used. The average radon concentration for the regions of Russia was earlier reconstructed on the basis of the annual reports of the form 4-DOZ. Information on morbidity and mortality from malignant neoplasms in Russia was obtained from annual reports issued by the Р. Hertsen Moscow Oncology Research Institute. As a surrogate of the level of infection with Human Papillomavirus, the incidence of cervix cancer was used. The smoking prevalence was estimated applying data on the incidence of tongue cancer.Results: taking into account smoking and infection with Human Papillomavirus, it is possible to obtain estimates of lung cancer excess relative risk when induced by radon in dwellings consistent with the results of case-control studies.Conclusion: the analysis of regionally aggregated data on deaths from lung cancer in Russia, the average level of indoor radon concentrations and significant risk factors for lung cancer confirms the linear threshold-free concept of radiation-induced carcinogenesis.

  14. Ventilation influence upon indoor air radon level

    International Nuclear Information System (INIS)

    Tian Deyuan

    1995-01-01

    Levels of indoor radon in air are studied by a continuous electrostatic radon monitor under normal living conditions to evaluate the influence of air conditioned ventilation on indoor air radon level. Results show that the indoor air radon concentrations are not much more than those without household conditioner living condition, although using household conditioner requires a sealed room which should lead to a higher radon level. Turning on air conditioner helps lower indoor radon level. Therefore, the total indoor air Rn levels are normal > ventilation > exhaust or in-draft > exhaust plus in-draft

  15. A cost-effectiveness analysis of radon protection methods in domestic properties: a comparative case study in Brixworth, Northamptonshire, UK

    International Nuclear Information System (INIS)

    Coskeran, Thomas; Denman, Antony; Phillips, Paul; Tornberg, Roger

    2006-01-01

    Building regulations in the UK have since 1992 required that radon-proof membranes be installed in new domestic properties to protect residents against the adverse effects of radon. This study compares the cost-effectiveness of the current regulatory regime with an alternative that would entail new properties being tested for radon after construction, and being remediated if necessary. The alternative regime is found to be more cost-effective for a sample of properties in Brixworth, Northamptonshire, UK. For this regime, the central estimate of cost per quality-adjusted life-year gained, the measure of cost-effectiveness used, is Pounds 2869 compared to Pounds 6182 for installing membranes, results suggesting a case for re-examining the current regulations on radon protection in new properties. Pilot studies will, however, be needed to consider how different means of protecting residents of new properties against radon might operate in practice and to provide improved evidence on their relative cost-effectiveness

  16. Study of the contribution of the radon in the measurement with an automatic gamma probe

    International Nuclear Information System (INIS)

    Caveda Ramos, C.A.; Dominguez Levy, O.; Alonso Abad, D.; Montalvan Estrada, A.; Fabelo Bonet, O.

    2008-01-01

    In this work, study about the influence of the radon in the daily measurements of the dose rate absorbed in air due to the environmental gamma radiation is achieved. This magnitude is measured each ten minutes for the Gamma Tracer probe, which is located in the western station of the National Network of Environmental Radiological Surveillance of the Republic of Cuba, this station belongs to the Center of Protection and Hygiene of the Radiations (CPHR). For achieving such study approximately 157 680 measurements of the gamma dose rate corresponding the period 2004-2006 were analyzed. The gamma probe used has two independent counter channels which are both complemented with a Geiger-Muller detector; also it can only detect gamma radiation and perform measurements of the gamma dose rate between 8.7 n Gy/h and 8.7 mGy/h. This probe is located at the height of 3.5 m and is exposed to the sun rays directly. For improving the interpretation of the data, the average of all the values of gamma dose rate was calculated, for each hour of the 365 days of the year. The values were also monthly averaged out. The data were processed by employing the software Gamma Red which was improved by adding some options. A comparison between the results obtained and the annual radon variation internationally published was made. With the present study, it was proved that the main contribution to the daily measurements of the dose rate absorbed in the air due to environmental gamma radiation, on stable weather conditions, is associated with the radon daughters which emit gamma radiation. (author)

  17. Some comments on the feasibility of an epidemiological study on incidence of lung cancer due to exposure to radon daughters

    International Nuclear Information System (INIS)

    Elsasser, U.

    1988-01-01

    For two different designs of a study - cohort and case control study - estimates of required sample size have been made on the basis of lung cancer risk assessment data for exposure to radon and radon daughters. The estimates have shown that a cohort study is not feasible for reasons of unjustifiably high requirements. A case control study, however, may contribute to clarifying the lung cancer risk, especially if the basic overall entity is limited to the population group of over 50 years of age. (orig.) [de

  18. Scopingsreport Radon

    NARCIS (Netherlands)

    Blaauboer RO; Vaas LH; Hesse JM; Slooff W

    1989-01-01

    Dit scopingsrapport vormt een onderdeel van de voorbereiding tot het opstellen van het basisdocument radon. Het doel van dit rapport is het algemene kennisniveau van de deelnemers aan de scopingsbijeenkomst aangaande radon op eenzelfde peil te brengen en discussie- en beslispunten inzake de

  19. The Montana Radon Study: social marketing via digital signage technology for reaching families in the waiting room.

    Science.gov (United States)

    Larsson, Laura S

    2015-04-01

    I tested a social marketing intervention delivered in health department waiting rooms via digital signage technology for increasing radon program participation among priority groups. I conducted a tri-county, community-based study over a 3-year period (2010-2013) in a high-radon state by using a quasi-experimental design. We collected survey data for eligible participants at the time of radon test kit purchase. Radon program participation increased at the intervention site (t38 = 3.74; P = .001; 95% confidence interval [CI] = 4.8, 16.0) with an increase in renters (χ(2)1,228 = 4.3; P = .039), Special Supplementary Nutrition Program for Women, Infants, and Children families (χ(2)1,166 = 3.13; P = .077) and first-time testers (χ(2)1,228 = 10.93; P = .001). Approximately one third (30.3%; n = 30) attributed participation in the radon program to viewing the intervention message. The intervention crossover was also successful with increased monthly kit sales (t37 = 2.69; P = .01; 95% CI = 1.20, 8.47) and increased households participating (t23 = 4.76; P signage technology by 2 health departments.

  20. A study of environmental radon levels in rammed earth dwellings in the south west of Western Australia

    International Nuclear Information System (INIS)

    Walsh, M.; Jennings, P.

    2002-01-01

    Indoor radon and thoron progeny Equilibrium Equivalent Concentrations (EEC) were measured with a portable 'Radon Sniffer' in 10 rammed earth dwellings and 10 conventional dwellings in Margaret River in the South West of Western Australia. Natural background gamma radiation was also measured within the dwellings. The results of this study show that the mean indoor radon progeny concentrations in rammed earth and non-rammed earth dwellings was 24 Bq m -3 EEC and 9.3 Bq m -3 EEC respectively. The mean indoor thoron progeny concentrations in rammed earth and non-rammed earth dwellings was 3.9 Bq m -3 EEC and 0.8 Bq m -3 EEC respectively. The ranges of combined indoor radon and thoron progeny concentrations in rammed earth and non-rammed earth dwellings were between 2.1 and 76 Bq m -3 EEC and 2.0 and 27 Bq m -3 EEC respectively. The mean annual effective radiation dose equivalents from combined indoor radon and thoron progeny concentrations EEC using UNSCEAR's (1982) conversion factors in rammed earth and non-rammed earth dwellings were 4.1 mSv y -1 and 2.2 mSv y -1 respectively. Copyright (2002) Australasian Radiation Protection Society Inc

  1. Project Radon

    International Nuclear Information System (INIS)

    Ekholm, S.

    1988-01-01

    The project started in March 1987. The objective is to perform radon monitoring in 2000 dwellings occupied by people employed by State Power Board and to continue to contribute to the development of radon filters. The project participates in developing methods for radon measurement and decontamination and in adapting the methods to large scale application. About 400 so called radon trace measurements (coarse measurement) and about 10 action measurements (decontamination measurement) have been made so far. Experience shows that methods are fully applicable and that the decontamination measures recommended give perfectly satisfactory results. It is also established that most of the houses with high radon levels have poor ventilation Many of them suffer from moisture and mould problems. The work planned for 1988 and 1989 will in addition to measurements be directed towards improvement of the measuring methods. An activity catalogue will be prepared in cooperation with ventilation enterprises. (O.S.)

  2. Technique and equipment for measuring volume activity of radon in the air of radon laboratories and clinics

    International Nuclear Information System (INIS)

    Vorob'ev, I.B.; Krivokhatskij, A.S.; Nekrasov, E.V.; Nikolaev, V.A.; Potapov, V.G.; Terent'ev, M.V.

    1990-01-01

    Usability of a new equipment-technique combination for measuring radon activity in the air of radon laboratories and balneological clinics is studied. The complex includes nitrate-cellulose detector, radon chamber, Aist, Istra type spark counters and technique of spark counting. The method sensitivity is 50 Bqxm 3 , the error is 30%. Usability and advisability of track method in radon laboratories and balneological clinics for simultaneous measurement in several points of integral volumetric radon activities are confirmred. The method permits to carry out rapid and accurate bulk investigations. The results of determining mean volumetric radon activity in the air in different points of radon laboratory and radon clinics are presented

  3. Aerosol microphysics of indoor radon

    International Nuclear Information System (INIS)

    1989-01-01

    To provide an improved description for the deposition of charge on ultrafine aerosol particles, we have introduced for the first time into aerosol studies the ''jellium'' model potential to quantitatively describe the interaction energy at long range between a conducting particle and an ion (here modeled as a point charge). The benefit of utilizing this potential, in its linearized approximation, is that it accounts for the response of the particle's conduction electrons to the field of the ion rather than relying upon a macroscopic picture whose validity is nuclear for sufficiently small particles. In the limit of large separations or of larger particles, the jellium and image potentials converge rapidly implying that no inconsistency exists between the generally-accepted approach for larger particles and our contribution. As a part of our work, we have given an accurate fit to the experimental data in the literature on the charging rate of neutral particles in the 4--50 nm range of radii without the need for assumptions other than of the charging ion properties. The results of this work will contribute to the ability to model charged radon daughter cluster ion attachment to high-diffusivity particles and conversely to the ability to model charge attachment on high-diffusivity uncharged particles containing a radon daughter

  4. Experimental Investigation of Radio-Turbulence Induced Diffusion -- Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Spitz, H. B.; Usman, S.

    2005-07-07

    The outcome of this research project suggests that the transport of radon in water is significantly greater than that predicted solely by molecular diffusion. The original study was related to the long term storage of {sup 226}Ra-bearing sand at the DOE Fernald site and determining whether a barrier of water covering the sand would be effective in reducing the emanation of {sup 222}Rn from the sand. Initial observations before this study found the transport of radon in water to be greater than that predicted solely by molecular diffusion. Fick's law on diffusion was used to model the transport of radon in water including the impact associated with radioactive decay. Initial measurements suggested that the deposition of energy in water associated with the radioactive decay process influences diffusion and enhances transport of radon. A multi-region, one-dimensional, steady-state transport model was used to analyze the movement of radon through a sequential column of air, water and air. An effective diffusion coefficient was determined by varying the thickness of the water column and measuring the time for transport of {sup 222}Rn through of the water barrier. A one-region, one-dimensional transient diffusion equation was developed to investigate the build up of radon at the end of the water column to the time when a steady-state, equilibrium condition was achieved. This build up with time is characteristic of the transport rate of radon in water and established the basis for estimating the effective diffusion coefficient for {sup 222}Rn in water. Several experiments were conducted using different types and physical arrangements of water barriers to examine how radon transport is influenced by the water barrier. Results of our measurements confirm our theoretical analyses which suggest that convective forces other than pure molecular diffusion impact the transport of {sup 222}Rn through the water barrier. An effective diffusion coefficient is defined that

  5. Radon balneotherapy and physical activity for osteoporosis prevention: a randomized, placebo-controlled intervention study.

    Science.gov (United States)

    Winklmayr, Martina; Kluge, Christian; Winklmayr, Wolfgang; Küchenhoff, Helmut; Steiner, Martina; Ritter, Markus; Hartl, Arnulf

    2015-03-01

    Low-dose radon hyperthermia balneo treatment (LDRnHBT) is applied as a traditional measure in the non-pharmacological treatment of rheumatic diseases in Europe. During the last decades, the main approach of LDRnHBT was focused on the treatment of musculoskeletal disorders, but scientific evidence for the biological background of LDRnHBT is weak. Recently, evidence emerged that LDRnHBT influences bone metabolism. We investigated, whether combined LDRnHBT and exercise treatment has an impact on bone metabolism and quality of life in a study population in an age group at risk for developing osteoporosis. This randomized, double-blind, placebo-controlled trial comprised guided hiking tours and hyperthermia treatment in either radon thermal water (LDRnHBT) or radon-free thermal water (PlaceboHBT). Markers of bone metabolism, quality of life and somatic complaints were evaluated. Statistics was performed by linear regression and a linear mixed model analysis. Significant changes over time were observed for most analytes investigated as well as an improvement in self-assessed health in both groups. No significant impact from the LDRnHBT could be observed. After 6 months, the LDRnHBT group showed a slightly stronger reduction of the osteoclast stimulating protein receptor activator of nuclear kB-ligand compared to the PlaceboHBT group, indicating a possible trend. A combined hyperthermia balneo and exercise treatment has significant immediate and long-term effects on regulators of bone metabolism as well as somatic complaints. LDRnHBT and placeboHBT yielded statistically equal outcomes.

  6. Study of epidemiological risk of lung cancer in Mexico due indoor radon exposure

    Science.gov (United States)

    Ángeles, A.; Espinosa, G.

    2014-07-01

    In this work the lifetime relative risks (LRR) of lung cancer due to exposure to indoor 222Rn on the Mexican population is calculated. Cigarette smoking is the number one risk factor for lung cancer (LC), because that, to calculate the number of cases of LC due to exposure to 222Rn is necessary considers the number of cases of LC for smoking cigarette. The lung cancer mortality rates published by the "Secretaría de Salud" (SSA), the mexican population data published by the "Consejo Nacional de Población" (CONAPO), smoking data in the mexican population, published by the "Comisión Nacional Contra las Adicciones" (CONADIC), the "Organización Panamericana de la Salud" (OPS) and indoor 222Rn concentrations in Mexico published in several recent studies are used. To calculate the lifetime relative risks (LRR) for different segments of the Mexican population, firstly the Excess Relative Risk (ERR) is calculated using the method developed by the BEIR VI committee and subsequently modified by the USEPA and published in the report "EPA Assessment of Risks from Radon in Homes". The excess relative risks were then used to calculate the corresponding lifetime relative risks, again using the method developed by the BEIR VI committee. The lifetime relative risks for Mexican male and female eversmokers and Mexican male and female never-smokers were calculated for radon concentrations spanning the range found in recent studies of indoor radon concentrations in Mexico. The lifetime relative risks of lung cancer induced by lifetime exposure to the mexican average indoor radon concentration were estimated to be 1.44 and 1.40 for never-smokers mexican females and males respectively, and 1.19 and 1.17 for ever-smokers Mexican females and males respectively. The Mexican population LRR values obtained in relation to the USA and Canada LRR published values in ever-smokers for both gender are similar with differences less than 4%, in case of never-smokers in relation with Canada

  7. Treatment technology for removing radon from small community water supplies

    International Nuclear Information System (INIS)

    Kinner, N.E.; Quern, P.A.; Schell, G.S.; Lessard, C.E.; Clement, J.A.

    1989-01-01

    Radon contamination of drinking water primarily affects individual homeowners and small communities using ground-water supplies. Presently, three types of treatment processes have been used to remove radon: granular activated carbon adsorption (GAC), diffused-bubble aeration, and packed-tower aeration. In order to obtain data on these treatment alternatives for small communities water supplies, a field evaluation study was conducted on these three processes as well as on several modifications to aeration of water in storage tanks considered to be low cost/low technology alternatives. The paper presents the results of these field studies conducted at a small mobile home park in rural New Hampshire. The conclusion of the study was that the selection of the appropriate treatment system to remove radon from drinking water depends primarily upon: (1) precent removal of process; (2) capital operating and maintenance costs; (3) safety (radiation); and (4) raw water quality (Fe, Mn, bacteria and organics)

  8. Initial study on the quantitative determination of radon in varied construction dwllings in the province of Pichincha, Ecuador

    International Nuclear Information System (INIS)

    Ayala, Maria; Penaherrera, Patricio; Munoz, Victor

    1993-01-01

    This research involves data from dwellings built up with different types of raw materials found spread in the province of Pichincha - Ecuador. The SSNTD method using a cellulose nitrate sensible film LR-115 was used for the research. The incidence of temperature, altitude, ventilation on the concentration gas radon-222 were also subject of a qualitative study. Eventually, the results show that the adobe dwellings and/or poorly ventilated dwellings prodece maximum concentration of radon-222 than first or second floor, meaning that, the gas is also coming up from the ground. In any case the level of radon-222 concentration is less than the acceptet limit, 200 Bq/m 3, by UNCEAR. Only places, such as Mindo and Calderon, surpass the limit

  9. Surface diffusion studies by optical diffraction techniques

    International Nuclear Information System (INIS)

    Xiao, X.D.

    1992-11-01

    The newly developed optical techniques have been combined with either second harmonic (SH) diffraction or linear diffraction off a monolayer adsorbate grating for surface diffusion measurement. Anisotropy of surface diffusion of CO on Ni(l10) was used as a demonstration for the second harmonic dim reaction method. The linear diffraction method, which possesses a much higher sensitivity than the SH diffraction method, was employed to study the effect of adsorbate-adsorbate interaction on CO diffusion on Ni(l10) surface. Results showed that only the short range direct CO-CO orbital overlapping interaction influences CO diffusion but not the long range dipole-dipole and CO-NI-CO interactions. Effects of impurities and defects on surface diffusion were further explored by using linear diffraction method on CO/Ni(110) system. It was found that a few percent S impurity can alter the CO diffusion barrier height to a much higher value through changing the Ni(110) surface. The point defects of Ni(l10) surface seem to speed up CO diffusion significantly. A mechanism with long jumps over multiple lattice distance initiated by CO filled vacancy is proposed to explain the observed defect effect

  10. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon

    International Nuclear Information System (INIS)

    Weinberg, C.R.

    1995-01-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of α-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining α-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting open-quotes measurement confoundingclose quotes can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. 18 refs., 4 figs

  11. Is radon 222 an appropriate tracer for the study of seismic precursors?

    International Nuclear Information System (INIS)

    Richon, P.; Heritier, T.; Sebe, O.; Maffat, I.; Holtzappfel, T.; Le Hesran, E.; Geber, O.; Ulziibat, M.; Demberel, S.; Oyun-Erdene, M.; Bilguun, M.

    2015-01-01

    Radon 222 is a natural radionuclide that can be measured in air, water, and soil in very, very small quantities. Experiments performed in laboratories have shown that a local strain on a rock has an impact on the mobility of the radon gas and as local strains increase with the approach of an earthquake, it is considered that radon abnormal measurements may help predicting earthquakes. The first stage to extrapolate laboratory results to large-scale application is to master the metrology of the radon gas. A campaign of measurements achieved in Mongolia on the Emeelt site has allowed an optimization of radon metrology and of the positioning of the probes. Preliminary results have shown that abnormal values of radon concentrations that are not correlated with local meteorology, appear a few days before local seismic activity resumes

  12. Basic study on positive effects of radon inhalation on pet's health

    International Nuclear Information System (INIS)

    Kataoka, Takahiro; Sakoda, Akihiro; Kawabe, Atsushi; Hanamoto, Katsumi; Yamaoka, Kiyonori; Tokunaga, Rikizo

    2012-01-01

    Radon inhalation using our radon exposure device activated anti-oxidative function in some organs of mouse. To assess the possibility of its application to veterinary care, healthy dogs and cats with chronic renal failure were inhaled radon at a concentration of 5500 Bq/m 3 for 30 minutes every 2 days for 30 days. In result, radon inhalation within a relatively long time period significantly decreased the triglyceride level of dogs. On the other hand, some cats increased the volume of drinking water by radon inhalation and the creatinine level in blood of these cats was decreased to normal level. These findings suggest that radon inhalation may have curative properties against chronic renal failure. (author)

  13. Diffusion studies of anamorphic GRIN lenses

    Science.gov (United States)

    Sekh, Md. Asraful; SoodBiswas, Nisha; Sarkar, Samir; Basuray, Amitabha

    2016-12-01

    The present paper reports the diffusion study of cylindrical GRIN rod with elliptical cross section, developed by ion exchange process. The diffusion equation takes the form of Mathieu equations when transform into elliptic coordinate system and the solutions are derived in terms of angular and radial Mathieu functions. Computations of eigenvalues and expansion coefficients as well as angular and radial Mathieu functions are made which shows good agreement with the existing results. Simpler expression for ionic concentration is derived using asymptotic formulae of the functions which are used for final computation of ionic concentration of diffusing cations in elliptic GRIN. The plot of change in concentration versus diffusion depth along different directions approximately correlates with the results obtained by an earlier experimental study.

  14. An active radon sampling device for high humidity places

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F. [Department of Nuclear Engineering and Fluid Mechanics, University of the Basque Country (UPV/EHU), Alameda Urquijo s/n 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Department of Nuclear Engineering and Fluid Mechanics, University of the Basque Country (UPV/EHU), Alameda Urquijo s/n 48013 Bilbao (Spain); Alegria, N.; Herranz, M. [Department of Nuclear Engineering and Fluid Mechanics, University of the Basque Country (UPV/EHU), Alameda Urquijo s/n 48013 Bilbao (Spain)

    2010-01-15

    An active radon measurement device has been developed to be used in workplaces with a relative humidity of 100% for spot measurements of radon concentration. A mathematical model based on the convective-diffusive transport equation is used in the design of this system, which has been used to measure the radon concentration in the Pozalagua cave (Biscay, at Northern of Spain). From the obtained radon values the public and workers doses have been obtained.

  15. Radon concentration in a house of Calvados

    International Nuclear Information System (INIS)

    Leleyter, L.; Riffault, B.; Mazenc, B.

    2010-01-01

    Recent studies indicate a link between the risk of lung cancer and residential radon exposure. However, in France, awareness of this problem was made relatively late. Accordingly this study examines the radon concentration in a private home in Calvados (Normandy region). Findings show that the presence of a fireplace in a house can accelerate radon convective transfer, and that simple adjustments to interior and exterior accommodation can significantly reduce radon concentrations in the home. (authors)

  16. Particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist Route "Liczyrzepa" Mine in Kowary Adit

    Science.gov (United States)

    Wołoszczuk, Katarzyna; Skubacz, Krystian

    2018-01-01

    Central Laboratory for Radiological Protection, in cooperation with Central Mining Institute performed measurements of radon concentration in air, potential alpha energy concentration (PAEC), particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist-Educational Route "Liczyrzepa" Mine in Kowary Adit. A research study was developed to investigate the appropriate dose conversion factors for short-lived radon progeny. The particle size distribution of radon progeny was determined using Radon Progeny Particle Size Spectrometer (RPPSS). The device allows to receive the distribution of PAEC in the particle size range from 0.6 nm to 2494 nm, based on their activity measured on 8 stages composed of impaction plates or diffusion screens. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometres to about 20 micrometres using Aerodynamic Particle Sizer (APS) spectrometer and the Scanning Mobility Particle Sizer Spectrometer (SMPS).

  17. Radon problem in uranium industry

    International Nuclear Information System (INIS)

    Khan, A.H.; Raghavayya, M.

    1991-01-01

    Radon emission is invariably associated with the mining and processing of uranium ores. Radon (sup(222)Rn) enters mine atmosphere through diffusion from exposed ore body, fractures and fissures in the rocks and is also brought in by ground water. Being the progenitor of a series of short lived radioisotopes it contributes over 70% of the radiation dose to mine workers and thus accounts for nearly 30% of the total radiation doses received by workers in the whole nuclear industry. This paper summarises the data on radon emanation from the ore body, backfilled sands and mine water. Radon and its progeny concentrations in different haulage levels and stopes of the Jaduguda uranium mine are presented to emphasise the need for a well planned ventilation system to control radiation exposure of miners. Results of radon monitoring from a few exploratory uranium mines are included to indicate the need for a good ventilation system from inception of the mining operations. Relative contribution of mine exhaust and tailings surfaces to the environmental radon are also given. Some instruments developed locally for monitoring of radon and its progeny in mines and in the environment are briefly described to indicate the progress made in this field. (author). 17 refs., 2 figs., 6 tabs

  18. A hypothetical high level of radon output before a major geophysical event: a theoretical study

    International Nuclear Information System (INIS)

    Monnin, M.; Seidel, J.L.

    1988-01-01

    Variation of radon concentration may play the role of a precursor for seisms and volcanic eruptions. This variation depends on the motion of interstitial gases. A numerical model is presented. It describes the steady states of the radon concentration and mainly the transient states between two different steady states. For an up-flow of gases, it predicts the formation of an intense emission of radon over a short period of time, called a 'kludon' [fr

  19. Spatial and vertical distribution of radon and thoron in a typical Indian dwelling

    International Nuclear Information System (INIS)

    Vinay Kumar Reddy, K.; Gopal Reddy, Ch.; Yadagiri Reddy, P.; Rama Reddy, K.

    2012-01-01

    Radon and thoron have been identified as potential radiological health hazard and the dose estimation due to their exposure is an important task. Understanding their behavior in indoor environment helps in calculating the inhalation doses due to them. Present study aims at the distribution of radon and thoron concentrations in a typical Indian dwelling. Solid state nuclear track detectors are employed in the study. The concentration of radon is found to be invariant in indoor environment. The thoron concentration is found to decrease exponentially as a function of distance from the source (wall/floor). Solution of one dimensional diffusion equation is used for regression fittings for thoron variation, from which the diffusion constants and the exhalation rates were calculated. The diffusion constants varied from 0.00195 to 0.00540 m 2 s -1 . (author)

  20. Indoor and underground radon activity in the northern part of Bangladesh: a preliminary study

    International Nuclear Information System (INIS)

    Haque, A.K.F.; Islam, G.S.; Islam, M.A.

    1991-01-01

    CR-39 solid state nuclear track detectors were used to determine the indoor and underground radon activity at three locations in the northern part of Bangladesh. The indoor radon activity at Naogaon was found to be higher than that at Rajshahi and Ruppur. Radon concentration in the mud-built houses at Naogaon was estimated to be ∼ 500 Bq m -3 (14pCi 1 -1 ) which is more than three times the recommended limit. The underground radon emanation at Naogaon was found to be one order of magnitude higher than that at the other two places. (author)

  1. Study on radon and thoron levels in different types of granitic work industries around Tumkur city

    International Nuclear Information System (INIS)

    Nagabhushan, S.R.; Ujjinappa; Srilatha; Sannappa, J.

    2013-01-01

    Radon, Thoron and its progeny monitoring has become a global phenomenon due to its health hazards on human being. The concentration of radon, thoron and their progeny levels have been measured in different types of Granite and brick work industries around Tumkur city by using LR-115 type II Solid State Nuclear Track Detectors (SSNTDs) have been used for the measurement of these gases. The higher concentration of radon, thoron and their progeny were observed in the dwellings near brick industries compared to Granite cutting and polishing industries. The inhalation dose due to Radon, Thoron and their progeny to the workers and public living near these industries have been estimated. (author)

  2. A comparative study of indoor radon levels and inhalation dose in some areas of Punjab and Haryana, India

    International Nuclear Information System (INIS)

    Bajwa, B.S.; Singh, Harmanjit; Singh, Joga; Singh, Surinder

    2009-01-01

    Indoor radon concentrations have been measured for two consecutive half-year periods in a wide range of dwellings of some regions of Punjab and Haryana states. The objective was to find correlation between the variations of indoor radon levels with the sub-soil, local geology, type of building materials, etc. of the two regions. So keeping this in view the indoor radon measurements have been carried out in the dwellings of different villages around the Tusham ring complex, Bhiwani District, Haryana, known to be composed of acidic volcanics and the associated granites along with some villages of Amritsar District, Punjab. The indoor radon concentration in the dwellings around Tusham (Haryana) have been found to be varying from 120.5±95 to 915.2±233 Bq m -3 , whereas it ranges from 60.0±37 to 235.6±96 Bq m -3 for the dwellings of Punjab. The 222 Rn concentration observed at most of locations particularly around Tusham ring complex region is higher than that of all the villages studied in Punjab region. Local geology including embedded granitic rocks, sub-soil, etc. as well as building materials having higher radioactive content are the major contributors for the higher indoor radon levels observed in the dwelling around Tusham, where few dwellings have higher radon concentrations than the ICRP, 1993 recommendations. The annual effective dose equivalent has also been estimated for each location of the both regions, which has been found to be varying from 1.0 to 17.2 mSv/y. (author)

  3. Effects of periodic atmospheric pressure variation on radon entry into buildings

    Science.gov (United States)

    Tsang, Y. W.; Narasimhan, T. N.

    1992-06-01

    Using a mathematical model, we have investigated the temporal variations of radon entry into a house basement in the presence of time-dependent periodic variations of barometric pressure as well as a persistent small steady depressurization within the basement. The tool for our investigation is an integral finite difference numerical code which can solve for both diffusive and advective flux of radon in the soil gas which is treated as a slightly compressible fluid. Two different boundary conditions at the house basement are considered: (1) a dirt floor basement so that diffusion is equally or more important than advective transport, and (2) an "impermeable" cement basement except for a 1-cm-wide crack near the perimeter of the basement floor; in which case, advective transport of radon flux dominates. Two frequencies of barometric pressure fluctuation with representative values of amplitudes, based on a Fourier decomposition of barometric pressure data, were chosen in this study: one with a short period of 0.5 hour with pressure amplitude of 50 Pa, the other a diurnal variation with a period of 24 hours with the typical pressure amplitude of 250 Pa. For a homogeneous soil medium with soil permeability to air between 10-13 and 10-10 m2, we predict that the barometric fluctuations increase the radon entry into the basement by up to 120% of the steady radon inflow into the basement owing to a steady depressurization of 5 Pa. If soil permeability heterogeneity is present, such as the presence of a thin layer of higher permeability aggregate immediately below the basement floor, radon flux due to atmospheric pumping is further increased. Effects of pressure pumping on radon entry are also compared to diffusion-only transport when the steady depressurization is absent. It is found that contribution to radon entry is significant for the basement crack configuration. In particular, for pressure pumping at 0.5-hour period and for a homogeneous medium of permeability of 10

  4. Measurement and comparison of indoor radon levels in new and old buildings in the city of Muzaffarabad (Azad Kashmir), Pakistan. A pilot study

    International Nuclear Information System (INIS)

    Rafique, Muhammad; Jabeen, Shahida; Bukhari, Shujaht; Rahman, Saeed ur; Shahzad, Muhammad Ikram; Matiullah; Rahman, Said; Nasir, Tabassum

    2009-01-01

    Indoor radon concentrations have been measured in a limited number of dwellings in the state capital of Azad Jammu and Kashimir, Muzaffarabad city after the devastating earthquake of 2005. Radon detectors (CN-85 based box-type) were placed in the drawing rooms, bedrooms and kitchens of 35 houses, selected on the basis of their location and design as well as willingness and cooperation of householders from mid May to mid July 2007. The average radon concentrations were found to vary from 24 to 518 Bq m -3 , 41 to 380 Bq m -3 and 32 to 467 Bq m -3 in the bedrooms, drawing rooms and kitchens, respectively. The weighted average radon concentration in older houses was found to vary from 51 to 334 Bq m -3 and for newly constructed houses a considerable decrease in measured values (ranging from 14 to 102 Bq m -3 ) have been found. As Pakistan does not currently have a national reference (or action level) for radon in homes, therefore the present data has been compared with the data reported for other countries. Some of the houses studied were found to have higher radon concentrations. These higher values of indoor radon levels may be due to the poor ventilation and influence of the earthquake in creating new fissures and therefore new pathways for radon to enter into the buildings. (author)

  5. Measurement and comparison of indoor radon levels in new and old buildings in the city of Muzaffarabad (Azad Kashmir), Pakistan. A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Rafique, Muhammad; Jabeen, Shahida; Bukhari, Shujaht [Dept. of Physics, Univ. of Azad Jammu and Kashmir Muzaffarabad, Azad Kashmir (Pakistan); Rahman, Saeed ur [Dept. of Physics, COMSATS Inst. of Information Technology, Islamabad (Pakistan); Shahzad, Muhammad Ikram; Matiullah, [Physics Division, PINSTECH, Islamabad (Pakistan); Rahman, Said [SPAS Division, SPARCENT, SUPARCO HQs, Karachi (Pakistan); Nasir, Tabassum [Dept. of Physics, Gomal Univ., Dera Ismail Khan (Pakistan)

    2009-11-15

    Indoor radon concentrations have been measured in a limited number of dwellings in the state capital of Azad Jammu and Kashimir, Muzaffarabad city after the devastating earthquake of 2005. Radon detectors (CN-85 based box-type) were placed in the drawing rooms, bedrooms and kitchens of 35 houses, selected on the basis of their location and design as well as willingness and cooperation of householders from mid May to mid July 2007. The average radon concentrations were found to vary from 24 to 518 Bq m{sup -3}, 41 to 380 Bq m{sup -3} and 32 to 467 Bq m{sup -3} in the bedrooms, drawing rooms and kitchens, respectively. The weighted average radon concentration in older houses was found to vary from 51 to 334 Bq m{sup -3} and for newly constructed houses a considerable decrease in measured values (ranging from 14 to 102 Bq m{sup -3}) have been found. As Pakistan does not currently have a national reference (or action level) for radon in homes, therefore the present data has been compared with the data reported for other countries. Some of the houses studied were found to have higher radon concentrations. These higher values of indoor radon levels may be due to the poor ventilation and influence of the earthquake in creating new fissures and therefore new pathways for radon to enter into the buildings. (author)

  6. Radon and risk of cancer

    International Nuclear Information System (INIS)

    Rootwelt, K.

    1988-01-01

    The article reviews present knowledge on the possible detriment to health of radon in homes. It is concluded that inducement of lung cancer has neither been proved nor disproved. Large-scale epidemiological studies are in progress. Until the results of these studies have been reported, frightening anti-radon propaganda should be discouraged

  7. Results of the first 5 years of a study on year-to-year variations of radon concentration in Italian dwellings

    International Nuclear Information System (INIS)

    Bochicchio, F.; Ampollini, M.; Antignani, S.; Bruni, B.; Quarto, M.; Venoso, G.

    2009-01-01

    Radon concentration in air is subject to significant variations at different time scales, owing to several factors. In general, the shorter the time period considered, the larger the variations in radon concentration, e.g., day-to-day variations are usually higher than month-to-month variations. An average over 12 consecutive months is generally considered the best estimate of the long-term average radon concentration. Due to practical reasons, however, very few data are available on year-to-year variations. Year-to-year variations can have quite a relevant impact on radon policies and on the assessment of health risks from exposures to radon. Therefore, a project was started in 1996 aimed to evaluate year-to-year variations in a sample of dwellings. Systematic radon measurements have been made with LR 115 based radon detectors (closed type) in the living room and one bedroom of a sample of dwellings in Rome (Italy). The analysis of the results of the first five consecutive years of measurements, regarding the 76 dwellings included in the final analysis, showed relatively low year-to-year variations, with a median coefficient of variation of 14% (range 3%-42%), smaller than that observed in studies from other European countries. Therefore, in the analyzed sample, 12-month measurements can be considered a good estimate of the average radon concentration, at least within a 5-year period. This is quite important for radon regulations and policies, e.g. annual measurements could be recommended and repetition of radon measurements could not be necessary within periods of 5 years. Moreover, the impact of the observed year-to-year variations on the lung cancer risk estimated in the Italian epidemiological study is expected to be not high, if variations on periods up to about 30 years can be assumed similar to those observed in this study.

  8. Reduction of radon concentration in a basement workplace: study of the problem and characterization of the main parameters affecting the radon concentration

    International Nuclear Information System (INIS)

    Chiaberto, E.M.; Magnoni, M.; Righino, F.; Costa Laia, R.

    2002-01-01

    In this work is described the method used for the mitigation of high radon concentrations found in a basement workplace, the ARPA laboratory used for the metrology of EMF. In this lab was in fact measured a radon concentration up to 1900 Bq/m 3 , a value largely exceeding the Italian limit for workplaces (500 Bq/m 3 ). The basement workplace affected by radon is a room of around 500 m 3 with no windows and only one door, during work usually close, and therefore with a very low ventilation rate. In this workplace, usually two persons spent about 6 hour per day. Therefore their exposure to the radon and its decay products can attain a considerable value. For this people, accordingly to the accepted dosimetric models, an effective dose of several mSv per year could be estimated (ICRP Publication n. 65, 1993). It is thus important to reduce the radon concentration to acceptable levels, i.e. at least lower than 500 Bq/m 3 . This paper deals not only with the simple method used for the remedial action, but also to the investigation of the relevant parameters affecting the radon concentration. In particular, the monitoring of the radon concentration before and after the remedial action, allowed the calculation of the radon entry rates (Bq/s) and the ventilation rates (s-1) in the different experimental condition

  9. Radon reduction

    International Nuclear Information System (INIS)

    Hamilton, M.A.

    1990-01-01

    During a radon gas screening program, elevated levels of radon gas were detected in homes on Mackinac Island, Mich. Six homes on foundations with crawl spaces were selected for a research project aimed at reducing radon gas concentrations, which ranged from 12.9 to 82.3 pCi/l. Using isolation and ventilation techniques, and variations thereof, radon concentrations were reduced to less than 1 pCi/l. This paper reports that these reductions were achieved using 3.5 mil cross laminated or 10 mil high density polyethylene plastic as a barrier without sealing to the foundation or support piers, solid and/or perforated plastic pipe and mechanical fans. Wind turbines were found to be ineffective at reducing concentrations to acceptable levels. Homeowners themselves installed all materials

  10. Residential Radon Exposure and Incidence of Childhood Lymphoma in Texas, 1995–2011

    Directory of Open Access Journals (Sweden)

    Erin C. Peckham

    2015-09-01

    Full Text Available There is warranted interest in assessing the association between residential radon exposure and the risk of childhood cancer. We sought to evaluate the association between residential radon exposure and the incidence of childhood lymphoma in Texas. The Texas Cancer Registry (n = 2147 provided case information for the period 1995–2011. Denominator data were obtained from the United States Census. Regional arithmetic mean radon concentrations were obtained from the Texas Indoor Radon Survey and linked to residence at diagnosis. Exposure was assessed categorically: ≤25th percentile (reference, >25th to ≤50th percentile, >50th to ≤75th percentile, and >75th percentile. Negative binomial regression generated adjusted incidence rate ratios (aIRR and 95% confidence intervals (CI. We evaluated lymphoma overall and by subtype: Hodgkin (HL; n = 1248, Non-Hodgkin excluding Burkitt (non-BL NHL; n = 658, Burkitt (BL; n = 241, and Diffuse Large B-cell (DLBCL; n = 315. There was no evidence that residential radon exposure was positively associated with lymphoma overall, HL, or BL. Areas with radon concentrations >75th percentile had a marginal increase in DLBCL incidence (aIRR = 1.73, 95% CI: 1.03–2.91. In one of the largest studies of residential radon exposure and the incidence of childhood lymphoma, we found little evidence to suggest a positive or negative association; an observation consistent with previous studies.

  11. Geographical associations between radon and cancer: is domestic radon level a marker of socioeconomic status?

    International Nuclear Information System (INIS)

    Wolff, S.P.; Stern, G.

    1991-01-01

    Previous studies showing a geographical association between radon and various cancers, particularly the leukaemias and lymphomas, appear to be confounded by the role of radon levels as a surrogate for socioeconomic status. Higher socioeconomic status (at least at the UK county level) is correlated with higher levels of domestic radon. Controlling for the relationship between socioeconomic status and radon removes the correlation between radon exposure and lymphoproliferative disease. Reported associations between radon and lymphoproliferative disease (and possibly other cancers) may be secondary to socioeconomic variables. (author)

  12. Mechanisms and sources of radon entry in buildings constructed with modern technologies

    International Nuclear Information System (INIS)

    Zhukovsky, M.V.; Vasilyev, A.V.

    2014-01-01

    To investigate the influence of modern building construction technologies on the accumulation of radon indoor, 20 rooms in buildings constructed using mostly monolithic concrete or aerated concrete blocks have been studied. Dominance of the diffusion mechanism of radon entry in buildings constructed with modern technologies has been established. As a result of computer simulations it was found that the main contribution to the variability of radon concentration was made by changes in the ventilation rate. At a low ventilation rate ( -1 ) radon concentration above 200 Bq m -3 can be observed for residential buildings. There is a need for the regulation of the radium-specific activity in building materials. According to the estimates of this study, the content of 226 Ra in building materials should not exceed the value of 100 Bq kg -1 . (authors)

  13. Radon and lung cancer in Bangalore Metropolitan, India

    International Nuclear Information System (INIS)

    Sathish, L.A.; Nethravathi, K.S.; Ramachandran, T.V.

    2012-01-01

    Radon is a radioactive gas released from the normal decay of 238 U in rocks and soil. It is an invisible, odorless, tasteless gas that seeps up through the ground and diffuses into the air. In a few areas, depending on local geology, radon dissolves into ground water and can be released into the air when the water is used. Radon gas usually exists at very low levels outdoors. However, in areas without adequate ventilation, such as underground mines, radon can accumulate to levels that substantially increase the risk of lung cancer. Radon decays quickly, giving off tiny radioactive particles. When inhaled, these radioactive particles can damage the cells that line the lung. Long-term exposure to radon can lead to lung cancer, the only cancer proven to be associated with inhaling radon. Public interest in radon has been occasionally piqued by articles in the general press. Considerable attention has been given to the high radon levels that were uncovered in the Reading Prong region of Pennsylvania, following the discovery in late 1984 of extremely high levels in one home. Several epidemiological study programmes in different countries are in progress to estimate the population exposures due to natural radiation with a view to obtain the radiation risk coefficients at low dose rate levels. In this regard, radiation surveys in high background areas (HBRAs) can provide excellent settings for epidemiological studies relating to the effects of low doses of radiation. In view of these, a comprehensive estimate of the natural inhalation dose requires both 222 Rn and 220 Rn levels in the indoor atmosphere. In this outlook an attempt is made to investigate the 222 Rn and 220 Rn levels in dwellings of Bangalore Metropolitan, India. Three year results shows that the activity concentrations of 226 Ra, 232 Th, radon in ground water, the concentrations 222 Rn and 220 Rn and the dose rate (mSvy -1 ) are at alarming levels for the environment of Bangalore Metropolitan, India. The

  14. Radon/helium studies for earthquake prediction N-W Himalaya

    International Nuclear Information System (INIS)

    Virk, H.S.

    1999-01-01

    The paper presents the preliminary data of radon monitoring stated in the Himalayan orogenic belt. Radon anomalies are correlated with microseismic activity in the N-W Himalaya. The He/Rn ratio will be used as a predictive tool for earthquakes

  15. Entry of soil gas and radon into houses

    International Nuclear Information System (INIS)

    Andersen, C.E.

    1992-04-01

    Entry of soil gas and radon into houses has been investigated by experiments conducted at radon test structures and numerical or analytical modelling. The numerical model solves the steady-state equations for Darcy flow of soil-gas and combined diffusive and advective transport of radon. Model calculations were compared with results from field experiments conducted at Risoe National Laboratory, and it was found that there was good agreement between measured and modelled pressure coupling and radon concentration profiles. Discrepancies regarding absolute values of soil-gas entry rates and radon concentrations were observed. The numerical model has been used to study the importance of soil and building related factors on radon entry rates into slab-on-grade houses. It was found that, for a house with a 3 mm perimeter crack along the floor-wall joint, the entry was mainly determined by the soil permeability and building related factors such as house depressurization and presence of a capillary breaking layer of gravel below the slab. In a house with a bare soil floor, the diffusivity of the soil was found to be of principal importance for the entry rate even for moderate permeabilities. An analytical model was developed for the purpose of studying soil-gas entry rates into houses in response to non-static driving forces. It is based on the analogy between a 'buried drain' and a basement house with a perimeter crack. The structure was depressurized sinusoidally in time and the frequency dependent pressure couplings were measured. There was fairly good agreement between theoretical and experimental results. (LN) (26 tabs., 30 ills., 66 refs.)

  16. Radon measurements at IC-09 well of Chingshui geothermal field (Taiwan): A case study

    International Nuclear Information System (INIS)

    Chen, Y.; Kuo, T.; Fan, K.; Liang, H.; Tsai, C.; Chiang, C.; Su, C.

    2011-01-01

    Radon concentration was monitored during the flow tests of well IC-09 at the Chingshui geothermal field. The radon concentration was found to increase from 54 ± 29 to 983 ± 65 Bq/m 3 as a step function of production time, or cumulative production. The observed radon behavior can be explained by a radial composite model with the carbonate scales deposited in the skin zone near the well. The radius of skin zone near well IC-09 can be estimated with radon data at about 20 m using a plug flow model. Monitoring natural radon during the well flow tests is a helpful tracer to diagnose the formation damage near the well.

  17. Certain problems about radon. Pt.1

    International Nuclear Information System (INIS)

    Wu Huishan

    2005-01-01

    Discussion has been made on certain pointed out problems which presently influence the work and development of radon survey, and certain specific problems have been put forward which should be paid much attention and taken measures. Among the problems, some come from cognition, i.e. two kinds of balance and examination about radon, chief culprit of radon's daughter, multiply control and migration, the significance of radon in the water and soil, important standards for designing and evaluating the sites of construction projects, thoughts on the mechanism of the harm of radon and its daughters, diseases causing of both high and low radon, difficulty of emanation of indoor radon, normal low radon from natural marble; and others must be resolved specifically, i.e. establishment of national radon standards as quickly as possible, improvement of on-the-spot examination technique, national-wide radon survey with multiple disciplines and technology, the research on the mechanism of radon's harm and the establishment national radon study center. (authors)

  18. Experience gained with a case control study of risk factors in bronchial carcinoma - would the approach be suitable for assessment of the radon problem?

    International Nuclear Information System (INIS)

    Wichmann, H.E.

    1988-01-01

    In the USA and in Sweden, case control studies are being done for investigating the incidence of lung cancer and a possible association with indoor exposure to radon daughters. In the F.R.G., methods and results of a case control study of other risk factors in bronchial carcinoma are available, and the question currently discussed is whether the data obtained by this study, together with additional measurements, could be used to assess the radon problem, or whether an individual radon study should be done, and what its requirements would be. (orig.) [de

  19. Radon transport modelling: User's guide to RnMod3d

    International Nuclear Information System (INIS)

    Andersen, C.E.

    2000-08-01

    RnMod3d is a numerical computer model of soil-gas and radon transport in porous media. It can be used, for example, to study radon entry from soil into houses in response to indoor-outdoor pressure differences or changes in atmospheric pressure. It can also be used for flux calculations of radon from the soil surface or to model radon exhalation from building materials such as concrete. The finite-volume model is a technical research tool, and it cannot be used meaningfully without good understanding of the involved physical equations. Some understanding of numerical mathematics and the programming language Pascal is also required. Originally, the code was developed for internal use at Risoe only. With this guide, however, it should be possible for others to use the model. Three-dimensional steady-state or transient problems with Darcy flow of soil gas and combined generation, radioactive decay, diffusion and advection of radon can be solved. Moisture is included in the model, and partitioning of radon between air, water and soil grains (adsorption) is taken into account. Most parameters can change in time and space, and transport parameters (diffusivity and permeability) may be anisotropic. This guide includes benchmark tests based on simple problems with known solutions. RnMod3d has also been part of an international model intercomparison exercise based on more complicated problems without known solutions. All tests show that RnMod3d gives results of good quality. (au)

  20. Radon transport modelling: User's guide to RnMod3d

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, C.E

    2000-08-01

    RnMod3d is a numerical computer model of soil-gas and radon transport in porous media. It can be used, for example, to study radon entry from soil into houses in response to indoor-outdoor pressure differences or changes in atmospheric pressure. It can also be used for flux calculations of radon from the soil surface or to model radon exhalation from building materials such as concrete. The finite-volume model is a technical research tool, and it cannot be used meaningfully without good understanding of the involved physical equations. Some understanding of numerical mathematics and the programming language Pascal is also required. Originally, the code was developed for internal use at Risoe only. With this guide, however, it should be possible for others to use the model. Three-dimensional steady-state or transient problems with Darcy flow of soil gas and combined generation, radioactive decay, diffusion and advection of radon can be solved. Moisture is included in the model, and partitioning of radon between air, water and soil grains (adsorption) is taken into account. Most parameters can change in time and space, and transport parameters (diffusivity and permeability) may be anisotropic. This guide includes benchmark tests based on simple problems with known solutions. RnMod3d has also been part of an international model intercomparison exercise based on more complicated problems without known solutions. All tests show that RnMod3d gives results of good quality. (au)

  1. Studies on radon exhalation rate from building materials of Mysuru district, Karnataka

    International Nuclear Information System (INIS)

    Chandini, M.; Lavanya, B.S.K.; Chandrashekara, M.S.; Pruthvi Rani, K.S.

    2017-01-01

    In the present study, mass exhalation rate of 222 Rn from soil and building materials was studied using scintillation based Smart Radon Monitor (SRM) and also using Solid State Nuclear Track Detectors (SSNTD) employing Can Technique, following standard procedure. Mass exhalation rate of 222 Rn from various building material samples such as brick, sand, cement, concrete and from different types of flooring materials was determined. The results obtained from these methods were compared and analysed. The samples of construction materials were collected from various locations of Mysuru city. The city has an area of about 128 sq km with population of about 1 million. Mining industries of magnetite, dunite and lime stone are located around Mysuru city. In addition to this, quarrying and crushing of granite stones for building activities also exist nearby

  2. Radon measurements in indoor workplaces

    International Nuclear Information System (INIS)

    Tokonami, S.; Matsumoto, M.; Furukawa, M.; Fujimoto, K.; Fujitaka, K.; Pan, J.; Kurosawa, R.

    1996-01-01

    Radon measurements in several office buildings located in Tokyo were carried out with two types of device to study the time-dependent radon concentration in indoor workplaces. Both types of device use the electrostatic field for the collection of 218 Po onto the electrode of the detector. One provides an average radon concentration throughout the day. The other, in which a weekly timer is installed in the circuit of the electrode of the device, provides an average radon concentration during working hours (9:00-17:00, Monday-Friday). Although radon concentrations in Japanese dwellings have been found to be generally low, relatively high concentrations were observed in the office buildings. No consistent seasonal variation was recognised in this study. Little difference of average radon concentrations between working hours and the whole day was found throughout the year in two offices. On the other hand, a significant difference was observed in other offices. The operation of an air conditioner might change the radon concentration during working hours. From the results of radon measurements the average effective dose in the workplace was estimated to be 0.23 mSv for 2000 working hours in a year. (Author)

  3. CONTRIBUTION OF RADON FLOWS AND RADON SOURCES TO THE RADON CONCENTRATION IN A DWELLING

    NARCIS (Netherlands)

    DEMEIJER, RJ; STOOP, P; PUT, LW

    1992-01-01

    In this paper a model is presented for analysis of the radon concentrations in a compartment in terms of contributions from transport by flows of air between compartments and from radon sources in the compartment. Measurements were made to study the effect of increased natural ventilation of the

  4. Radon decay product in-door behaviour - parameter, measurement method, and model review

    International Nuclear Information System (INIS)

    Scofield, P.

    1988-01-01

    This report reviews parameters used to characterize indoor radon daughter behavior and concentrations. Certain parameters that affect indoor radon daughter concentrations are described and the values obtained experimentally or theoretically are summarized. Radon daughter measurement methods are reviewed, such as, PAEC, unattached daughters, particle size distributions, and plateout measurement methods. In addition, certain radon pressure driven/diffusion models and indoor radon daughter models are briefly described. (orig.)

  5. Experimental study on the aging process of the LR 115 cellulose nitrate radon detector

    International Nuclear Information System (INIS)

    Siems, M.; Freyer, K.; Treutler, H.-C.; Joensson, G.; Enge, W.

    2001-01-01

    An experimental determination of the aging process of cellulose nitrate detector material was based on the examination of special properties of the LR 115 solid state nuclear track detectors (SSNTDs) of various ages up to 18 years. The examined relevant parameters are the bulk etching rate v b and the track etching rate v t . These parameters are responsible for the appearance, the size and the registration efficiency of tracks of α-particles from radon gas in the detector. To find a correlation between these material parameters and the detector sensitivity an experimental calibration of indoor room and outdoor soil detector devices based on LR 115 took place at the Umweltforschungszentrum Leipzig-Halle (Germany). To avoid routine calibration work in external radon exposure facilities a correction of the age dependent calibration factors with the material parameters measured in one's own laboratory was targeted. In this study a general age dependence, however, was not found. The following statements for practical applications can be made. (i) the bulk etching rate v b for detectors of the same batch has a depth dependence and this dependence is constant over 2 years (LR 115 September 1994). (ii) detectors of different batches older than 5 years and stored at room temperature show an odd v b behaviour when v b is used for describing track shapes. (iii) the calibration factor of detectors of different batches that were stored at about +4 deg. C is constant over 5 years (LR 115 September 1994 and February 1999, Table 2). The conclusion is that LR 115 detectors not older than 5 years and stored in a refrigerator at about +4 deg. C should be preferred for radon measurements. Furthermore these detectors should be recalibrated every year and the microscope work of this calibrations should be performed by the same person who performs the measurements. In addition, a phenomenon related to fundamental track formation mechanisms was found, that the time straggling of the

  6. Radon exhalation rates of some granites used in Serbia

    Directory of Open Access Journals (Sweden)

    Nikolić Mladen D.

    2015-01-01

    Full Text Available In order to address concern about radon exhalation in building material, radon exhalation rate was determined for different granites available on Serbian market. Radon exhalation rate, along with mass exhalation rate and effective radium content were determined by closed chamber method and active continuous radon measurement technique. For this research, special chambers were made and tested for back diffusion and leakage, and the radon concentrations measured were included in the calculation of radon exhalation. The radon exhalation rate ranged from 0.161 Bq/m2h to 0.576 Bq/m2h, the mass exhalation rate from 0.167 Bq/kgh to 0.678 Bq/kgh, while the effective radium content was found to be from 12.37 Bq/kg to 50.23 Bq/kg. The results indicate that the granites used in Serbia have a low level of radon exhalation.

  7. Report of the special committee for the study of physiological effects of radon in human

    International Nuclear Information System (INIS)

    1998-01-01

    This report outlines the activities of the committee for the study of physiological effects of radon in human based on the presentation in the meetings by the members in the period, 1996-1998. The methods to estimate the exposed dose of radon (Rn) have been considerably improved now. But it is necessary to consider living conditions such as housing conditions, respiratory ratio as well as physical measurements such as Rn concentration, its balance factor, the ratio of non-absorbed component, for accurate evaluation of the physiological effects of Rn. This committee was established aiming to investigate the physiological effects of Rn in human bodies and solve the problems in this area. In a period from 1996 to 1998, meeting was held nine times by the committee. The respective main themes were as follows: the purpose of this committee and the plans of activities in future for the first meeting, indoor Rn level and balance factor for the second, outdoor Rn level and aerosol of its daughter nuclides for the third, respiratory air movement model for the 4th, Rn inhalation, epidemiological study of Rn for the 5th, epidemiological study of Rn for the 6th, problems in Rn level survey for the 7th, behaviors of Rn and its daughter nuclides in occupational environment for 9th, and variance in dose calibration factor and biological effects of α-ray for 10th. At present, dose evaluation and risk evaluation for Rn exposure include considerable uncertainty. Accurate dose evaluation for Rn is necessary to determine the limitation dose for human bodies to repress the physiological effects. (M.N.)

  8. Radon concentration and working level in the Exploratory Studies Facility (ESF)

    International Nuclear Information System (INIS)

    Stiver, J.H.; Tung, Chao-Hsiung.

    1995-01-01

    Radon-222 ( 222 Rn) and 222 Rn progeny WL monitoring in the Exploratory Studies Facility (ESF) was initiated to support regulatory compliance. Measurements were taken over two periods, in Test Alcove No. 1 of the ESF, about 60 m from the tunnel entrance. For both periods, 222 Rn concentration was less than 10% of the Derived Air Concentration (DAC) set forth in DOE Order 5480.11. Thus, these assessments were sufficient to demonstrate regulatory compliance. Based on these findings, quarterly 222 Rn and 222 Rn progeny monitoring was initiated. Two systems each were employed for 222 Rn and 222 Rn progeny measurement. No significant differences were observed between the respective systems. An interesting finding was that at the time the measurements were taken, barometric pressure appeared to be the predominant factor controlling 222 Rn concentration in the ESF. This was true even during periods of ventilation shutdown

  9. STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND THEIR PROGENY IN THE INDOOR ENVIRONMENT OF RAJPUR REGION OF UTTARAKHAND HIMALAYA.

    Science.gov (United States)

    Kandari, Tushar; Aswal, Sunita; Prasad, Mukesh; Pant, Preeti; Bourai, A A; Ramola, R C

    2016-10-01

    In the present study, the measurements of indoor radon, thoron and their progeny concentrations have been carried out in the Rajpur region of Uttarakhand, Himalaya, India by using LR-115 solid-state nuclear track detector-based time-integrated techniques. The gas concentrations have been measured by single-entry pin-hole dosemeter technique, while for the progeny concentrations, deposition-based Direct Thoron and Radon Progeny Sensor technique has been used. The radiation doses due to the inhalation of radon, thoron and progeny have also been determined by using obtained concentrations of radon, thoron and their progeny in the study area. The average radon concentration varies from 75 to 123 Bq m -3 with an overall average of 89 Bq m -3 The average thoron concentration varies from 29 to 55 Bq m -3 with an overall average of 38 Bq m -3 The total annual effective dose received due to radon, thoron and their progeny varies from 2.4 to 4.1 mSv y -1 with an average of 2.9 mSv y -1 While the average equilibrium factor for radon and its progeny was found to be 0.39, for thoron and its progeny, it was 0.06. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Radon and progeny sourced dose assessment of spa employees in balneological sites

    International Nuclear Information System (INIS)

    Kemal Uzun, Sefa; Demiroez, Isik

    2016-01-01

    This study was conducted in the scope of IAEA project with the name 'Establishing a Systematic Radioactivity Survey and Total Effective Dose Assessment in Natural Balneological Sites' (TUR/9/018), at the Health Physics department of Saraykoey Nuclear Research and Training Center (SANAEM). The aim of this study is estimation of radon and progeny sourced effective dose for the people who are working at the spa facilities by measuring radon activity concentration (RAC) at the ambient air of indoor spa pools and dressing rooms. As it is known, the source of the radon gas is the radium content of the earth crust. Therefore, thermal waters coming from ground may contain dissolved radon and the radon can diffuse water to air. So the ambient air of spa pools can contain serious RAC that depends on a lot of parameters. In this regard, RAC measurements were executed at the 70 spa facilities in Turkey. The measurements were done with both active and passive methods at ambient air of spa pools and dressing rooms. Thus, active measurements were carried out by using the Alphaguard R with diffusion mode during half an hour, and passive measurements were carried out by using the humidity resistive CR-39 radon detectors during 2 months. Results show that RAC values at ambient air of spa pools varies between 13 Bq m -3 and 10 kBq m -3 . Because long-term measurements are more reliable, if it is available, for dose calculations passive radon measurements (with CR-39 detectors) at ambient air of spa pools and dressing rooms were used, otherwise active measurement results were used. With the measurement by the conversion coefficients of ICRP 65 and occupational data of the employees has got from questionnaire forms, effective dose values were calculated. According to the calculations, spa employees are exposed to annual average dose between 0.05 and 29 mSv because of radon and progeny. (authors)

  11. Studying the Variation of Radon Level in Some Houses in Alexandria City, Egypt

    International Nuclear Information System (INIS)

    Abd El-Zaher, M.; Fahmi, N.M.

    2009-01-01

    Inhalation of indoor radon has been recognized as one of the health hazards. In the present work a set of indoor radon measurements was carried out, in different Egyptian houses in Alexandria city, built of the same type of building materials, using time-integrated passive radon dosimeters containing LR-115 Type II solid state nuclear track detector. Measurements were carried out from October 2007 to June 2008. The results show that, the radon concentrations and the annual effective dose in these houses varied from (38.62 to 120.39) Bq m-3 and (0.96 to 3.06) mSv y-1 respectively. The mean values of radon concentrations in living rooms, bedrooms, bathrooms, and kitchens were: (50.93±7.14), (63.75±7.63), (105.3± 14.67) and (82.38±8.35) Bq m -3 respectively. Also the mean values of annual effective dose were (1.26±0.17), (1.58±0.185), (2.63±0.36) and (2.0± 0.20) mSv y -1 , respectively. This data shows that, bathrooms and kitchens have significantly higher radon concentrations and annual radon dose

  12. Environmental and indoor study of Radon concentration in San Joaquin area, Queretaro, Mexico, first results

    International Nuclear Information System (INIS)

    Hinojo Alonso, N.A.; Kotsarenko, A.; Yutsis, V.; Hernandez Silva, G.; Perego, P.; Fazio, M.; Grimalsky, V.; Koshevaya, S.; Foglia, F.; Cortes Silva, A.; García Martínez, R.; Martínez Reyes, J.; Norini, G.; Groppelli, G.

    2013-01-01

    A highly contaminated zone with a maximum over 57,000 Bq/m 3 was discovered in a populated community “Agua de Venados” during the 2009–2011 soil Radon survey in San Joaquin, Queretaro State, Mexico. The indoor Radon monitoring accomplished in 2 different époques in a nearby 4 dwellings has shown an increased Radon hazard in 1 of the 4 buildings (about 300 Bq/m 3 ) during a rainy season and highly elevated indoor Radon levels (over 400 Bq/m 3 ) already in 3 buildings during a dry season. The averaged diurnal indoor Radon variations are in a correlation with the atmospheric pressure and the air humidity and are independent on the air temperature. The maximum indoor Radon hazard for dwellings is estimated for the morning interval 5–10 a.m. - Highlights: ► Emanative zone of 57,000 Bq/m 3 was found in area “Agua de Venados”. ► Indoor Radon level in a nearby dwellings elevates during a dry season. ► Maximum risk for residents was estimated during the daily interval 5–10 a.m

  13. Relation between residential radon concentrations and housing characteristics. The Cracow study

    International Nuclear Information System (INIS)

    Jedrychowski, W.; Flak, E.; Wesolowski, J.; Liu Kaishen

    1995-01-01

    The survey on indoor radon exposure was undertaken to explain whether the excess in lung cancer deaths in the Cracow city center may be attributed to this particular exposure. A total of 310 detectors was placed in households randomly chosen from three homogeneous strata of residential buildings. The first stratum included houses in the old city center constructed predominantly from stone bricks. The second stratum covered the city area with big apartment condominiums built from concrete blocks. The third stratum consisted of single family houses located in a suburban area. From each of these residency strata a random sample of an equal number of households was chosen, and the radon detectors were placed in households located at various levels of the buildings. The three-month radon sampling data were used to determine the distribution of various levels of radon in the households. In the measurement of radon exposure, Landauer α-track samplers were used. The data collected show that the type of building was the best single predictor of indoor radon concentrations. Other variables found to be associated significantly with indoor concentrations were the household level in the building and the house age. In general, residences with concrete slabs and dwellings with rarely-opened windows were found to have slightly higher radon concentrations. (author) 2 tabs., 15 refs

  14. A numerical study on the performance evaluation of ventilation systems for indoor radon reduction

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ji Eun; Park, Hoon Chae; Choi, Hang Seok; Cho, Seung Yeon; Jeong, Tae Young; Roh, Sung Cheoul [Yonsei University, Wonju (Korea, Republic of)

    2016-03-15

    Numerical simulations were conducted using computational fluid dynamics to evaluate the effect of ventilation conditions on radon ({sup 222}Rn) reduction performance in a residential building. The results indicate that at the same ventilation rate, a mechanical ventilation system is more effective in reducing indoor radon than a natural ventilation system. For the same ventilation type, the indoor radon concentration decreases as the ventilation rate increases. When the air change per hour (ACH) was 1, the indoor radon concentration was maintained at less than 100 Bq/m{sup 3}. However, when the ACH was lowered to 0.01, the average indoor radon concentration in several rooms exceeded 148 Bq/ m{sup 3}. The angle of the inflow air was found to affect the indoor air stream and consequently the distribution of the radon concentration. Even when the ACH was 1, the radon concentrations of some areas were higher than 100 Bq/m{sup 3} for inflow air angles of 5 .deg. and 175 .deg.

  15. Radon levels in Oslo schools

    International Nuclear Information System (INIS)

    Birovlev, A.

    2004-01-01

    Radon measurements using passive CR-39 detectors have been conducted in all schools in Oslo municipality during winter 2003/2004. Results are presented and discussed in the light of qualitative and quantitative factors, some of which are specific for schools as workplaces. Analysis is conducted with respect to factors relating to building construction type, ventilation principle, age of building, building size etc. The influence of ventilation type on radon levels is studied, and problems of investigations based purely on conventional passive radon detectors are noted. Over-estimation of radon concentration by passive detectors and day-night variations of indoor radon levels in buildings with mechanical ventilation systems are discussed. Several guiding principles for planning similar investigations based on above discussions are outlined. (author)

  16. Ion climate and radon concentration

    International Nuclear Information System (INIS)

    Busbarna, L.

    1981-01-01

    Characteristic values of radon concentration in natural ion climate and in open air were compared and the effect of artificially produced negative ion excess on the radon concentration of air was studied. The results show that the radon concentration measurable at the rise of negative ion excess is smaller than that in the case of natural equilibrium. This effect can be utilized lowering the background of the scintillation chambers, thus increasing their sensitivity. The negative ions of the artificial ion climate lower radon concentration in closed space. The question arises whether only the ion climate is responsible for the effects on the organism and on the nervous system or the radon concentration of the air also contributes to them. (author)

  17. Radon - To mobilise civil society

    International Nuclear Information System (INIS)

    2016-01-01

    As radon is one of the two main sources of exposure of population to ionizing radiations in France, is notably said to be responsible of 1.000 to 3.000 deaths for lung cancer per year, and could be at the origin of other cancers like child leukaemia, this set of articles evokes the different factors which promote radon transfer from soils to buildings, studies performed to better identify geological sources of radon, actions implemented to assess radon presence in dwellings (distribution of 'radon kits' in Brittany), the performance of radiological expertise by the IRSN on the request of public authorities, the project of dwelling inventory and population information. A second article reports examples of intervention by the IRSN to inform local authorities, inhabitants, academics, public utilities, building professions, and even children. Technical solutions adopted in the United Kingdom are briefly evoked

  18. Radon and its importance for animal hygiene

    International Nuclear Information System (INIS)

    Janowski, T.M.; Tombarkiewicz, B.

    1995-01-01

    Reconnaissance studies on radon concentration were carried out for various species of animal in animal housing in the Cracow region. It was found that the level of radon inside the livestock houses depended on the type of housing and animal species. In a cow shed the concentration of radon was higher by 25% than in the atmosphere, whereas in a piggery the radon level exceeded twice that in the ambient air. However, in a poultry house the radon concentration was over 20% lower then outside. (author). 9 refs

  19. Measurements of radon concentrations in dwelling houses

    International Nuclear Information System (INIS)

    Birkholz, W.; Klink, T.

    1993-01-01

    Radon and its daughter products gain in importance in health protection and radiation safety. Especially in the southern region of Saxony radon concentrations in dwellings may be high by former silver and uranium mines. We found radon contents of about 20.000 Bq/m 3 in dwellings. To redevelop such houses it is necessary to know intrude path of radon. In present work we studied different measuring systems, active and passive detectors, short and long term integrating devices. By means of investigation of radon sources several redeveloping methods are rates as well from radiological as from civil engineering point of view. (author)

  20. Application of nuclear track detectors for radon related measurments

    International Nuclear Information System (INIS)

    Abu-Jarad, F.A.

    1988-01-01

    The application of nuclear track detectors for radon related measurements is discussed. The ''Can Technique'', used for measuring radon emanation from building materials, walls and soil; the ''Working Level Monitor'', used for measuring short period working levels of radon daughters in houses; and ''Passive Radon Dosimeters'', used to measure radon levels in houses for long term (few months) periods are described. Application of nuclear track detectors for measuring the radon daughters plate-out on the surface of mixing fan blades and walls are discussed. The uranium content of some wall papers was found to be 6 ppm. The variation of radon progeny concentration in the same room was measured and supported by another study through Gas Chromatograph measurements. The independence of radon concentration on room level in high-rise buildings was established. The effect of sub-floor radon emanation on radon concentration in houses is dependent on whether there is sub-floor ventilation or not. (author)

  1. Radon penetration of concrete slab cracks, joints, pipe penetrations, and sealants

    NARCIS (Netherlands)

    Nielson, KK; Rogers, VC; Holt, RB; Pugh, TD; Grondzik, WA; deMeijer, RJ

    1997-01-01

    Radon movement through 12 test slabs with different cracks, pipe penetrations, cold joints, masonry blocks, sealants, and tensile stresses characterized the importance of these anomalous structural domains, Diffusive and advective radon transport were measured with steady-state air pressure

  2. Impact of structural parameters on the radon exhalation of building materials: Preliminary study

    International Nuclear Information System (INIS)

    Roelofs, L.M.M.

    1993-01-01

    Samples of mortar and sand-lime pieces with different percentages of fly ash are hardened at different relative humidities. The porosity distribution, the moisture and the radon exhalation of these samples are determined. Based on the data of the above-mentioned analyses, the thickness of the adsorbed water layer in the water-filled pores is estimated. The correlation between the structural parameters and the radon exhalation is investigated. If the radon exhalation process can be modelled, the radiation risk of applying fly ash in building materials can be controlled or reduced. The results do not yet show a clear indication. The applied methods have to be considered in more detail

  3. A study of diurnal variations of radon and thoron concentrations in different indoor environmental conditions

    International Nuclear Information System (INIS)

    Pant, Preeti; Prasad, Mukesh; Ramola, R.C.

    2015-01-01

    The measurements for diurnal variations in radon ( 222 Rn) and thoron ( 220 Rn) concentrations were performed in the different indoor conditions of Tehri Garhwal, Uttarakhand, India by using AlphaGUARD, Portable Radon Monitor and RAD7. While selecting the dwellings, the ventilation conditions, building materials, life style of the inhabitants and their exposure time indoors were also considered. The behavior of indoor radon and thoron concentrations was observed for different type of dwellings with different environmental conditions. The measurement techniques, results obtained and comparison of the results are discussed in details. (author)

  4. Preliminary study of the contamination by Radon Gas in dwelling enclosures in Costa Rica

    International Nuclear Information System (INIS)

    Loria, L.G.; Jimenez, R.; Gallardo, M.C.

    1993-01-01

    The use of Solid State Nuclear Track detectors (SSNTD), LR-115 type II-Quick, is one of the convenient technique to assess the average radiation levels of alpha activities in the environment. This technique has been used to assess the Radon concentration in some areas of San Jose, Costa Rica. Exposed SSNTD films are chemically etched in an alkaline solution and the density of alpha tracks are given as concentration (pCi/L) of Radon. The only known health effect associated with exposure to elevated levels of Radon is an increased risk of developing lung cancer. (authors). 10 refs, 4 figs, 3 tabs

  5. Radon measurements in Greece

    International Nuclear Information System (INIS)

    Georgiou, E.; Ntalles, K.; Molfetas, M.; Athanassiadis, A.; Proukakis, C.

    1988-01-01

    Studies of radon concentration in greek spas, in a cave, in constituents of the greek cement, in building materials in Greece and in greek mines have been published. Some preliminary studies of radon concentration in greek dwellings have been published. In order to get an idea of the problem in Greece we decided to carry out a national survey. Two different sites were selected: Athens, where domicile about 40% of the greek population and Domatia, a small village in northern Greece 600Km from Athens, located in an area known to have soil with increased uranium concentrations

  6. Evaluation of the performance characteristics of radon and radon-daughter concentration measurement devices under controlled environmental conditions

    International Nuclear Information System (INIS)

    Pearson, M.D.

    1989-04-01

    The Technical Measurements Center (TMC) conducted a study to expose 10 radon and 7 radon-daughter concentration measurement devices in the DOE/GJPO Radon/Radon-Daughter Environmental Chamber for a series of 24 controlled-environment tests. The tests evaluated the devices' response to temperature, relative humidity, dew point, condensation-nuclei concentration, radon-daughter/radon equilibrium ratio, and non-uniform radon and radon-daughter concentration. Devices were evaluated for linear response as a function of concentration. In addition to response to environmental parameters, the evaluation included determining the utility of the devices in providing reasonable assurance of compliance with the radon and radon-daughter concentration standards for DOE remedial action programs. This reasonable assurance criterion is based on a coefficient of variation of 25 percent for devices deployed for year-long measurements and a coefficient of variation of 18 percent for devices deployed for intermittent sampling. 39 refs., 65 figs., 33 tabs

  7. Alpha scintillation radon counting

    International Nuclear Information System (INIS)

    Lucas, H.F. Jr.

    1977-01-01

    Radon counting chambers which utilize the alpha-scintillation properties of silver activated zinc sulfide are simple to construct, have a high efficiency, and, with proper design, may be relatively insensitive to variations in the pressure or purity of the counter filling. Chambers which were constructed from glass, metal, or plastic in a wide variety of shapes and sizes were evaluated for the accuracy and the precision of the radon counting. The principles affecting the alpha-scintillation radon counting chamber design and an analytic system suitable for a large scale study of the 222 Rn and 226 Ra content of either air or other environmental samples are described. Particular note is taken of those factors which affect the accuracy and the precision of the method for monitoring radioactivity around uranium mines

  8. Radon: an environmental pollutant

    International Nuclear Information System (INIS)

    Mills, W.A.

    1979-01-01

    Radiological concerns with the disposal and use of mining and milling residues have heightened to the point that federal agencies are asking or being asked to formulate new regulactions for controlling radon daughters from a variety of sources - radioactivity previously considered to be part of our natural environment. Based on information derived from epidemiologic studies of underground miners, particularly uranium miners, the health impact on the general public is being projected. Depending on the assumptions made, these projections vary widely. Because of these variations in health risks, decisions on control measures have even wider implications on economic and social considerations. Thus the question: is radon an environmental pollutant. While not fully answering the question, recognizing the uncertainties in assessing and controlling radon daughters can put the question in better perspective

  9. Studies of ionic diffusion in crystalline rock

    International Nuclear Information System (INIS)

    Ohlsson, Yvonne

    2001-01-01

    Matrix diffusion is of great importance in delaying radionuclides escaping from a deep geologic repository, on their way to the biosphere. There are, however, poorly understood mechanisms related to transport in pores with charged pore surfaces. Ions are affected by this charge and may be repelled or attracted by it. The rate of transport may be reduced, or even enhanced, as a result of this. Transport of ions is studied by traditional diffusion experiments, but mainly by a faster electrical conductivity method. With this method the pore connectivity, the formation factor variability and its relation to the porosity, as well as the surface conductivity are investigated. The method is compared. with traditional diffusion experiments, and an in-situ application is suggested and qualitatively tested. Furthermore, surface diffusion is studied by evaluating literature data and recently developed diffusion models. The pore connectivity reached to a depth of at least 15 cm in the rocks studied. The formation factor did not generally decrease with increasing sample length. It was also found that not only cations in the free pore water add to the electrical conductivity, but also at least part of those sorbed to the pore surfaces of the minerals. This surface conductivity influences the determination of the formation factor in low ionic strength pore waters, and was also found to be a function of the formation factor. It was furthermore dependent on the type of ion at the surface, giving for example a higher conductivity for Na + than for Cs + . It is not fully understood which part of the sorbed ions that are mobile. A simple model was developed assigning the mobile ions to the diffuse layer, and this model explained experimental data for diffusion of Cs + in clay well. This is contradicted by surface conductivity measurements that have shown that most mobile ions are found behind the Stern layer. The in-situ formation factor determination method seems promising. The most

  10. Remedial measures in Swedish and Norwegian houses - application of radon and radon decay product measurements

    International Nuclear Information System (INIS)

    Just, G.; Philipsborn, H. von; Matolin, M.; Molzahn, D.

    1998-01-01

    Houses and apartments in Sweden and Norway with excessive indoor radon concentrations were studied in detail with a variety of methods, standard and novel ones recently developed. For suitable remediation it is necessary to distinguish soil radon and exhalation from blue (porous) concrete. Our CARBOTEST-S is a simple, sensitive, in-situ method to quantify radon exhalation from existing walls, as well as radon permeability of different protective foils and final quality control of foils applied to existing walls. (orig.) [de

  11. Studies about diffusion through grain boundary

    International Nuclear Information System (INIS)

    Allevato, C.E.

    1983-01-01

    Samples with layers of gold-silver and silver-chromium were deposited in high vacuum (10 -5 -10 -6 Torr) on glass and sodium chloride substrates. After deposition, these films were annealed at different temperatures and analysed by Rutherford Backscattering, Auger Spesctroscopy and Transmission Electron Microscopy. A simulated convolution was done using a computer in order to evalute the precision of the particle detector employed in the backscattering. The concentration profiles used to determine the diffusion coefficient were obtained by Auger electron spectroscopy. This technique demanded a study of sputtering rate to convert time of sputtering in thickness. This rate was determined by two methods. Analyses of the samples of silver-chromium, heated up to 250 0 C, by transmission electron microscopy and Auger electron spectroscopy, indicated the presence of oxide in small isolated regions, as crystallites. Values of the diffusion coefficient and activation energy related to the diffusion through the volume and by the grain boundary were determined by Suzuoka's method. The system Ag/Cr, due to its high grain boundary density, led to an increase of the diffusion coefficient so that this coefficient and the activation energy were obtained only from the grain boundary. (Author) [pt

  12. Scopingreport radon

    International Nuclear Information System (INIS)

    Blaauboer, R.O.; Vaas, L.H.; Hesse, J.M.; Slooff, W.

    1989-09-01

    This report contains general information on radon concerning the existing standards, sources and emissions, the exposure levels and effect levels. lt serves as a basis for the discussion during the exploratory melting to be held in November/December 1989, aimed at determining the contents of the Integrated Criteria Document Radon. Attention is focussd on Rn-222 (radon) and Rn-220 (thoron), presently of public interest because of radon gas pollution in private homes. In the Netherlands air quality standards nor product standards for the exhalation rate of building materials have been recommended. The major source of radon in the Netherlands is the soil gas (> 97%), minor sources are phosphate residues and building materials (> 2% in total). Hence, the major concern is the transfer through the inhalation of air, the lung being the most critical organ at risk to develop cancer. Compared to risks for humans, the risks of radon and its daughters for aquatic and terrestric organisms, as well as for agricultural crops and livestock, are assumed to be limited. In the Netherlands the average dose for man due to radon and thoron progeny is appr. 1.2 mSv per year, the estimated dose range being 0.1-3.5 mSv per year. This dose contributes for about 50% to rhe total exposure due to all sources of ionizing radiation. Of this dose respectively 80% is caused by radon and about 90% is received indoor. The estimated dose for the general population corresponds to a risk for inducing fatal cancers of about 15 x 10-6 per year, ranging from 1.2 x 10-6 to 44 x 10-6 which exceeds the risk limit of 1 x 10-6 per year -as defined in the standardization policy in the Netherlands for a single source of ionizing radiation-with a factor 15 (1- 44). Reduction of exposure is only possible in the indoor environment. Several techniques have been described to reduce the indoor dose, resulting from exhalation of the soil and building materials. )aut- hor). 37 refs.; 3 figs.; 8 tabs

  13. Combined effect of radon exposure and smoking on lung cancer risk - result of a case-control study among Czech miners

    International Nuclear Information System (INIS)

    Tomasek, Ladislav

    2010-01-01

    Because of the predominant role of cigarette smoking as a cause of lung cancer, an understanding of the joint effect of smoking and radon exposure is needed for the assessment of the risk from radon. The aim of the present work is to verify differences in smoking specific risk coefficients observed earlier (BEIR VI). The present study includes two cohorts of uranium miners in west and central Bohemia and one cohort of burnt clay miners exposed to radon. In the nested study, for each case of lung cancer (observed in 1954-2007) with smoking data up to three controls were selected from all cohort members matched by year of birth, age, and the cohort. Data on smoking in the study were collected from subjects in person, from medical records, and from relatives. The statistical assessment of the study was based on conditional logistic regression with linear dependence of estimated relative risk on radon exposure

  14. Radon assay for SNO+

    Energy Technology Data Exchange (ETDEWEB)

    Rumleskie, Janet [Laurentian University, Greater Sudbury, Ontario (Canada)

    2015-12-31

    The SNO+ experiment will study neutrinos while located 6,800 feet below the surface of the earth at SNOLAB. Though shielded from surface backgrounds, emanation of radon radioisotopes from the surrounding rock leads to back-grounds. The characteristic decay of radon and its daughters allows for an alpha detection technique to count the amount of Rn-222 atoms collected. Traps can collect Rn-222 from various positions and materials, including an assay skid that will collect Rn-222 from the organic liquid scintillator used to detect interactions within SNO+.

  15. Particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist Route “Liczyrzepa” Mine in Kowary Adit

    Directory of Open Access Journals (Sweden)

    Wołoszczuk Katarzyna

    2018-01-01

    Full Text Available Central Laboratory for Radiological Protection, in cooperation with Central Mining Institute performed measurements of radon concentration in air, potential alpha energy concentration (PAEC, particle size distribution of the radon progeny and ambient aerosols in the Underground Tourist-Educational Route “Liczyrzepa” Mine in Kowary Adit. A research study was developed to investigate the appropriate dose conversion factors for short-lived radon progeny. The particle size distribution of radon progeny was determined using Radon Progeny Particle Size Spectrometer (RPPSS. The device allows to receive the distribution of PAEC in the particle size range from 0.6 nm to 2494 nm, based on their activity measured on 8 stages composed of impaction plates or diffusion screens. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometres to about 20 micrometres using Aerodynamic Particle Sizer (APS spectrometer and the Scanning Mobility Particle Sizer Spectrometer (SMPS.

  16. Radon in public buildings; Radon in oeffentlichen Gebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, H.; Flesch, K. [IAF - Radiooekologie GmbH, Dresden (Germany); Hermann, E. [B.P.S. Engineering GmbH, Zwickau (Germany); Loebner, W. [Wismut GmbH, Chemnitz (Germany); Leissring, B. [Bergtechnisches Ingenieurbuero GEOPRAX, Chemnitz (Germany)

    2009-07-01

    From the Free State of Saxony, a study was commissioned to survey how reliable measurements to characterize the radon situation in public buildings at a reasonable financial and human effort can be carried out to reduce radiation exposure in public buildings. The study approach was for 6 objects. To characterize the radon situation the time evolution measurement of radon concentrations of more than 1 to 2 weeks turned out to be sufficient. A novel data analysis enables the identification of a ''typical daily alteration of the radon concentration'' depending on the ventilation conditions and the daily use of the offices or class rooms. The identification of typical diurnal radon variations for the working time and weekends or holidays is of fundamental importance for assessing the exposure situation in public buildings. It was shown that the radon concentration during working time are in general much lower than in the times when the buildings (offices) are unused. It turned out that the long-term radon measurements with nuclear track detectors within distinct time regimes (day / night, working hours / leisure time) by utilizing switch modules are very efficient to estimate the actual exposure. (orig.)

  17. Contribution of waterborne radon to home air quality

    International Nuclear Information System (INIS)

    Deb, A.K.

    1994-01-01

    Radon-222 is a member of the uranium decay chain and is formed from the decay of radium-226. Radon and its decay products emit alpha particles during the decay process. If radon is inhaled, alpha particles emitted from inhaled radon and its daughters increase the risk of lung cancer. Radon is soluble in water; thus when radon comes in contact with groundwater it dissolves. The radon concentration in groundwater may range from 100 pCi/L to 1,000,000 pCi/L. When water with a high radon level is used in the home, radon is released from the water to the air and thus can increase indoor air radon concentration. Considering the estimated health risk from radon in public water supply systems, EPA has proposed a maximum contaminant level (MCL) of 300 pCi/L for radon in public drinking water supplies. To address the health risks of radon in water and the proposed regulations, the American Water Works Association Research Foundation (AWWARF) initiated a study to determine the contribution of waterborne radon to radon levels in indoor household air

  18. Diffusion Modeling: A Study of the Diffusion of “Jatropha Curcas ...

    African Journals Online (AJOL)

    Consequently, the study recommended the use of diffusion networks which integrate interpersonal networks, and multimedia strategies for the effective diffusion of innovation such as Jacodiesel in Adamawa State and other parts of the country. Keywords: Sustainability, Diffusion, Innovation, Communicative Influence, ...

  19. The measurement of radon and thoron by solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Khan, H.A.; Akhwand, R.A.; Bukhari, K.M.; Saddarudin, A.

    1976-01-01

    Experiments have been conducted to study a) the development and annealing properties of the latent damage trails produced by radon/thoron alpha particles in plastic Solid State Nuclear Track Detectors (SSNTDs), and b) the diffusion properties of radon and thoron in various media by using SSNTDs. The information thus obtained has been employed for a) the optimization of the conditions for the construction of radon/thoron dosimeters for uranium/thorium mines, and b) the use of SSNTDs for the prospection and estimation of uranium and thorium. The results indicate that these gases can diffuse even through rocks, and cellulose nitrate detectors, LR-115 and CA80-15, can be profitably employed in dosimetry, prospection, and for the discrimination between uranium and thorium deposits. (orig.) [de

  20. Managing Radon in Schools

    Science.gov (United States)

    EPA recommends testing all schools for radon. As part of an effective IAQ management program, schools can take simple steps to test for radon and reduce risks to occupants if high radon levels are found.

  1. Metrology of radon and thoron concentrations

    International Nuclear Information System (INIS)

    Durcik, M; Vicanova, M.

    1998-01-01

    The alpha spectrometry measurements of radon (radon-222) and thoron (radon-220) concentrations by ionisation chamber, used only in laboratory conditions are described in this paper. For the measurements of radon and thoron in dwellings and work areas was proposed diffusion double chamber detector with track detector. The described dosimeter is very useful for routine measurement and would be applied in measuring of radon and thoron concentrations in caves and dwellings. Big disadvantage of the dosimeter is small holes in cover and it could not be used in dusty areas. From previous measurements of the equilibrium equivalent thoron concentrations by semiconductor detector the measured values ranged from 0.1 to 5.6 Bq m -3 in the Slovak kindergartens were obtained

  2. Measurement of exhalation rate of radon and radon concentration in air using open vial method

    International Nuclear Information System (INIS)

    Horiuchi, Kimiko; Ishii, Tadashi.

    1991-01-01

    It was recognized that more than half of total exposure dose on human subject is caused by radon and its decay products which originate from naturally occurring radioactive substances (1988 UNSCEAR). Since then the exhalation of radon from the ground surface has received increasing attention. The authors have developed a new method for the determination of radon in natural water using toluene extraction of radon and applying a liquid scintillation counter of an integral counting technique which is able to get the absolute counting of radon. During these studies, the authors found out that when a counting vial containing of Liquid scintillator (LS)-toluene solution, without a lid, is exposed to the atmosphere for a while, dissolution of radon clearly occurs due to high solubility of radon into toluene layer. To extend this finding for the determination of radon in the atmosphere, the authors devised a new method to actively collect the atmosphere containing radon in a glass bottle by discharging a definite amount of water in it, which is named as open-vial dynamic method. The radon concentration can be easily calculated after the necessary corrections such as the partition coefficient and others. Applying proposed method to measure the radon exhalation rate from the ground surface and radon concentration in air of the dwelling environment, radioactive mineral spring zone and various geological formation such as granitic or sedimentary rocks. (author)

  3. Meta-analysis of thirty-two case-control and two ecological radon studies of lung cancer.

    Science.gov (United States)

    Dobrzynski, Ludwik; Fornalski, Krzysztof W; Reszczynska, Joanna

    2018-03-01

    A re-analysis has been carried out of thirty-two case-control and two ecological studies concerning the influence of radon, a radioactive gas, on the risk of lung cancer. Three mathematically simplest dose-response relationships (models) were tested: constant (zero health effect), linear, and parabolic (linear-quadratic). Health effect end-points reported in the analysed studies are odds ratios or relative risk ratios, related either to morbidity or mortality. In our preliminary analysis, we show that the results of dose-response fitting are qualitatively (within uncertainties, given as error bars) the same, whichever of these health effect end-points are applied. Therefore, we deemed it reasonable to aggregate all response data into the so-called Relative Health Factor and jointly analysed such mixed data, to obtain better statistical power. In the second part of our analysis, robust Bayesian and classical methods of analysis were applied to this combined dataset. In this part of our analysis, we selected different subranges of radon concentrations. In view of substantial differences between the methodology used by the authors of case-control and ecological studies, the mathematical relationships (models) were applied mainly to the thirty-two case-control studies. The degree to which the two ecological studies, analysed separately, affect the overall results when combined with the thirty-two case-control studies, has also been evaluated. In all, as a result of our meta-analysis of the combined cohort, we conclude that the analysed data concerning radon concentrations below ~1000 Bq/m3 (~20 mSv/year of effective dose to the whole body) do not support the thesis that radon may be a cause of any statistically significant increase in lung cancer incidence.

  4. Diffusion in liquids a theoretical and experimental study

    CERN Document Server

    Tyrrell, H J V

    1984-01-01

    Diffusion in Liquids: A Theoretical and Experimental Study aims to discuss the principles, applications, and advances in the field of diffusion, thermal diffusion, and thermal conduction in liquid systems. The book covers topics such as the principles of non-equilibrium thermodynamics; diffusion in binary and multicompetent systems; and experimental methods of studying diffusion processes in liquids. Also covered in the book are topics such as the theoretical interpretations of diffusion coefficients; hydrodynamic and kinetic theories; and diffusion in electrolyte systems. The text is recommen

  5. Uranium mill tailings and radon

    International Nuclear Information System (INIS)

    Hanchey, L.A.

    1981-01-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the US may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action Program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100

  6. Uranium mill tailings and radon

    Energy Technology Data Exchange (ETDEWEB)

    Hanchey, L A

    1981-04-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the United States may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

  7. Uranium mill tailings and radon

    Energy Technology Data Exchange (ETDEWEB)

    Hanchey, L A

    1981-01-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the US may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action Program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

  8. Assessing the effectiveness of slab flooring as a barrier to soil gas and radon infiltration

    International Nuclear Information System (INIS)

    Williamson, A.D.; Fowler, C.S.; McDonough, S.E.

    1995-01-01

    Experimental studies on the entry of soil gas and radon into slab-on-grade buildings have been carried out in instrumented, single-zone test structures. This work, as part of the Florida Radon Research Program, focused on the effectiveness of slab flooring variants as barriers to soil gas/radon entry. A second objective was the study of the role of subslab fill soil as both a potential source of and barrier to radon entry. Studies were made in well-sealed (∼ 600 mm 2 ELA) unoccupied test buildings placed on well-characterized, radium-bearing sandy fill soil. The buildings were instrumented with data acquisition systems to continuously monitor indoor radon concentrations, differential pressures at several subsurface locations, weather conditions, and soil moisture. The response of the structures to mechanical depressurization as well as natural driving forces was measured. Limited measurements were made regarding direct diffusive transport of radon through apparently intact concrete slabs, as well as transport through cracks in the floor structure

  9. Experimental study of diffuse auroral precipitations

    International Nuclear Information System (INIS)

    Mouaia, K.

    1983-01-01

    First chapter is devoted to low energy electron precipitation in the evening sector of the auroral magnetosphere, during quiet and disturbed magnetic periods. Four subjects are studied in detail: the latitude distribution of the varied auroral forms and their relations to external magnetosphere; the time coefficients related to precipitations, the form and the dynamic of the diffuse precipitation equatorial frontier; the precipitation effect on the ionosphere concentration. The last part of the chapter shows that the plasma convection in the magnetosphere, associated to wave-particle interactions near the equatorial accounts for the principal characteristics of the evening sector diffuse electronic precipitations. The second chapter deals with subauroral precipitations of low energy ions, after the magnetospheric substorms, in the high latitude regions of the morning sector [fr

  10. Current status of radon and radium monitoring at the Federal University of Technology (UTFPR), PR, Brazil

    International Nuclear Information System (INIS)

    Paschuk, Sergei A.; Correa, Janine N.; Kappke, Jaqueline; Schelin, Hugo R.; Denyak, Valeriy; Barbosa, Laercio; Perna, Allan F.N.

    2011-01-01

    Numerous and systematic studies performed in different countries for many decades resulted in the explicit conclusion that radon exposure, as well as its progeny, is the main cause of lung cancer among non-smokers. All three natural radon isotopes ( 222 Rn, 220 Rn and 219 Rn) are produced in the three principal natural radioactive decay chains. Specifically, the 222 Rn is produced by the decay series of 238 U and proceeded from α-decay of 226 Ra. Current work describes the present status and obtained results concern