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Sample records for high radon emanation

  1. High sensitivity radon emanation measurements.

    Science.gov (United States)

    Zuzel, G; Simgen, H

    2009-05-01

    The presented radon detection technique employs miniaturized ultra-low background proportional counters. (222)Rn samples are purified, mixed with a counting gas and filled into a counter using a special glass vacuum line. The absolute sensitivity of the system is estimated to be 40 microBq (20 (222)Rn atoms). For emanation investigations two metal sealed stainless steel vessels and several glass vials are available. Taking into account their blank contributions, measurements at a minimum detectable activity of about 100 microBq can be performed.

  2. Radon emanation from low-grade uranium ore.

    Science.gov (United States)

    Sahu, Patitapaban; Mishra, Devi Prasad; Panigrahi, Durga Charan; Jha, Vivekanand; Patnaik, R Lokeswara

    2013-12-01

    Estimation of radon emanation in uranium mines is given top priority to minimize the risk of inhalation exposure due to short-lived radon progeny. This paper describes the radon emanation studies conducted in the laboratory as well as inside an operating underground uranium mine at Jaduguda, India. Some of the important parameters, such as grade/(226)Ra activity, moisture content, bulk density, porosity and emanation fraction of ore, governing the migration of radon through the ore were determined. Emanation from the ore samples in terms of emanation rate and emanation fraction was measured in the laboratory under airtight condition in glass jar. The in situ radon emanation rate inside the mine was measured from drill holes made in the ore body. The in situ(222)Rn emanation rate from the mine walls varied in the range of 0.22-51.84 × 10(-3) Bq m(-2) s(-1) with the geometric mean of 8.68 × 10(-3) Bq m(-2) s(-1). A significant positive linear correlation (r = 0.99, p 222)Rn emanation rate and the ore grade was observed. The emanation fraction of the ore samples, which varied in the range of 0.004-0.089 with mean value of 0.025 ± 0.02, showed poor correlation with ore grade and porosity. Empirical relationships between radon emanation rate and the ore grade/(226)Ra were also established for quick prediction of radon emanation rate from the ore body.

  3. Radon emanation from radium specific adsorbents.

    Science.gov (United States)

    Alabdula'aly, Abdulrahman I; Maghrawy, Hamed B

    2010-01-01

    Pilot studies were undertaken to quantify the total activity of radon that is eluted following no-flow periods from several Ra-226 adsorbents loaded to near exhaustion. The adsorbents studied included two types of barium sulphate impregnated alumina (ABA-8000 and F-1) and Dowex MSC-1 resin treated by either barium hydroxide or barium chloride. In parallel, radium loaded plain activated aluminas and Dowex MSC-1 resin were similarly investigated. The results revealed that radon was quantitatively eluted during the first few bed volumes of column operation after no-flow periods. Although similar radon elution profiles were obtained, the position of the radon peak was found to vary and depended on the adsorbent type. Radon levels up to 24 and 14 kBq dm(-3) were measured after a rest period of 72h from radium exhausted Dowex MSC-1 treated with barium chloride and F-1 impregnated alumina with barium sulphate, respectively. The eluted radon values measured experimentally were compared to those calculated theoretically from accumulated radium quantities for the different media. For plain adsorbents, an agreement better than 10% was obtained. For treated resin-types a consistency within 30% but for impregnated alumina-types high discrepancy between respective values were obtained.

  4. 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.

  5. Radon emanation fractions from concretes containing fly ash and metakaolin

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Lange, Sarah C., E-mail: taylorlanges@utexas.edu [Department of Civil, Architectural, and Environmental Engineering, 1 University Station C1748, The University of Texas at Austin, Austin, TX 78712 (United States); Juenger, Maria C.G. [Department of Civil, Architectural, and Environmental Engineering, 1 University Station C1748, The University of Texas at Austin, Austin, TX 78712 (United States); Siegel, Jeffrey A. [Department of Civil, Architectural, and Environmental Engineering, 1 University Station C1748, The University of Texas at Austin, Austin, TX 78712 (United States); Department of Civil Engineering, 35 St. George Street, University of Toronto, Toronto, ON, M5S 1A4 (Canada)

    2014-01-01

    Radon ({sup 222}Rn) and progenies emanate from soil and building components and can create an indoor air quality hazard. In this study, nine concrete constituents, including the supplementary cementitious materials (SCMs) fly ash and metakaolin, were used to create eleven different concrete mixtures. We investigated the effect of constituent radium specific activity, radon effective activity and emanation fraction on the concrete emanation fraction and the radon exhalation rate. Given the serious health effects associated with radionuclide exposure, experimental results were coupled with Monte Carlo simulations to demonstrate predictive differences in the indoor radon concentration due to concrete mixture design. The results from this study show that, on average, fly ash constituents possessed radium specific activities ranging from 100 Bq/kg to 200 Bq/kg and emanation fractions ranging from 1.1% to 2.5%. The lowest emitting concrete mixture containing fly ash resulted in a 3.4% reduction in the concrete emanation fraction, owing to the relatively low emanation that exists when fly ash is part of concrete. On average, the metakaolin constituents contained radium specific activities ranging from 67 Bq/kg to 600 Bq/kg and emanation fractions ranging from 8.4% to 15.5%, and changed the total concrete emanation fraction by roughly ± 5% relative to control samples. The results from this study suggest that SCMs can reduce indoor radon exposure from concrete, contingent upon SCM radionucleotide content and emanation fraction. Lastly, the experimental results provide SCM-specific concrete emanation fractions for indoor radon exposure modeling. - Highlights: • Fly ash or metakaolin SCMs can neutralize or reduce concrete emanation fractions. • The specific activity of constituents is a poor predictor of the concrete emanation fraction. • Exhalation from fly ash concretes represents a small fraction of the total indoor radon concentration.

  6. Anomalous radon emanation linked to preseismic electromagnetic phenomena

    Directory of Open Access Journals (Sweden)

    Y. Omori

    2007-10-01

    Full Text Available Anomalous emanation of radon (222Rn was observed preceding large earthquakes and is considered to be linked to preseismic electromagnetic phenomena (e.g. great changes of atmospheric electric field and ionospheric disturbances. Here we analyze atmospheric radon concentration and estimate changes of electrical conditions in atmosphere due to preseismic radon anomaly. The increase of radon emanation obeys crustal damage evolution, following a power-law of time-to-earthquake. Moreover, the radon emanation decreases the atmospheric electric field by 40%, besides influencing the maximum strength of atmospheric electric field by 104–105 V/m enough to trigger ionospheric disturbances. These changes are within the ranges observed or explaining electromagnetic phenomena associated with large earthquakes.

  7. Radon emanation fractions from concretes containing fly ash and metakaolin.

    Science.gov (United States)

    Taylor-Lange, Sarah C; Juenger, Maria C G; Siegel, Jeffrey A

    2014-01-01

    Radon ((222)Rn) and progenies emanate from soil and building components and can create an indoor air quality hazard. In this study, nine concrete constituents, including the supplementary cementitious materials (SCMs) fly ash and metakaolin, were used to create eleven different concrete mixtures. We investigated the effect of constituent radium specific activity, radon effective activity and emanation fraction on the concrete emanation fraction and the radon exhalation rate. Given the serious health effects associated with radionuclide exposure, experimental results were coupled with Monte Carlo simulations to demonstrate predictive differences in the indoor radon concentration due to concrete mixture design. The results from this study show that, on average, fly ash constituents possessed radium specific activities ranging from 100 Bq/kg to 200 Bq/kg and emanation fractions ranging from 1.1% to 2.5%. The lowest emitting concrete mixture containing fly ash resulted in a 3.4% reduction in the concrete emanation fraction, owing to the relatively low emanation that exists when fly ash is part of concrete. On average, the metakaolin constituents contained radium specific activities ranging from 67 Bq/kg to 600 Bq/kg and emanation fractions ranging from 8.4% to 15.5%, and changed the total concrete emanation fraction by roughly ±5% relative to control samples. The results from this study suggest that SCMs can reduce indoor radon exposure from concrete, contingent upon SCM radionucleotide content and emanation fraction. Lastly, the experimental results provide SCM-specific concrete emanation fractions for indoor radon exposure modeling.

  8. Radon emanation from phosphogypsum and related mineral samples in Cyprus

    Energy Technology Data Exchange (ETDEWEB)

    Lysandrou, M. [Geological Survey Department, Ministry of Agriculture, Natural Resources and Environment (Cyprus); Department of Chemistry, University of Cyprus, P.O. Box 20537, Cy-1678 Lefkosia (Cyprus); Charalambides, A. [Geological Survey Department, Ministry of Agriculture, Natural Resources and Environment (Cyprus); Pashalidis, I. [Department of Chemistry, University of Cyprus, P.O. Box 20537, Cy-1678 Lefkosia (Cyprus)], E-mail: pspasch@ucy.ac.cy

    2007-10-15

    Radon emanation rates from phosphogypsum samples have been determined to assess the radiological impact of radon emanated from a phosphogypsum disposal site. For comparison corresponding measurements were conducted with samples of phosphate rock, fertilizer, natural gypsum, and calcite. The experimental data show that phosphate rock and phosphogypsum samples emanate radon in significantly higher rates (up to almost two orders of magnitude). The exhalation rates determined for samples obtained from a phosphogypsum stack in Cyprus range from 0.35 to 1.1Bqh{sup -1}. This, consequently, may result in increased radon levels in dwellings build and excessive radiation exposure to workers residing on the stack, which could reach in extreme cases values up to 17mSvy{sup -1}.

  9. Study of radon emanation from uranium mill tailings. Relations between radon emanating power and physicochemical properties of the material; Etude de l'emanation du radon a partir de residus de traitement de minerais d'uranium. Mise en evidence de relations entre le facteur d'emanation et les caracteristiques du materiau

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, D

    1999-07-01

    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)

  10. Mechanisms of radon loss from zircon: Microstructural controls on emanation and diffusion

    Science.gov (United States)

    Eakin, Marty; Brownlee, S. J.; Baskaran, M.; Barbero, L.

    2016-07-01

    Understanding how radon escapes from minerals is important for many fields in Earth science, yet few studies have focused on the mechanisms for radon escape. We measured radon emanation rate and radon loss upon heating for crushed aliquots of three large zircon crystals from three localities: Mud Tank (Australia), Bancroft (Canada), and Malawi (Africa). Our study, in conjunction with published data, shows that the room temperature radon emanation coefficient (REC) varies over 5 orders of magnitude in zircon. For low U zircon, Mud Tank, there are variations in REC that appear to be related to annealing at different temperatures, possibly due to annealing of fission tracks, however, all REC values for Mud Tank zircon are within error of one another. Bancroft and Malawi zircons have higher U content and do not show any systematic relationship of REC to annealing temperature. Results from Mud Tank zircon suggest that partial annealing of fission tracks decreases REC, but when all fission tracks are annealed REC reaches a maximum. REC in zircons with high U content, Bancroft and Malawi, is slightly higher than in zircon with lower U, although results are within error. Results of measurements of radon loss upon heating suggest that radon diffusion is slow, ∼30% of the radon is lost during heating at 975 °C for 48 h. Samples heated a second time yield less fractional radon loss, ∼10%, suggesting that diffusion parameters are changed during heating at temperatures ⩾975 °C, which is likely the result of annealing of radiation damage. Diffusion parameters calculated from the fractional loss experiments reflect diffusion in highly radiation damaged or metamict zircons. Our results indicate that internal microstructures in zircon, such as fission tracks and alpha-radiation damage, influence radon escape for diffusion and recoil mechanisms, and hence if these effects can be further characterized, measurements of 222Rn escape have the potential to be useful for probing

  11. EVALUATION OF RADON EMANATION FROM SOIL WITH VARYING MOISTURE CONTENT IN A SOIL CHAMBER

    Science.gov (United States)

    The paper describes measurements to quantitatively identify the extent to which moisture affects radon emanation and diffusive transport components of a sandy soil radon concentration gradient obtained in the EPA test chamber. The chamber (2X2X4 m long) was constructed to study t...

  12. A comparison between active and passive techniques for measurements of radon emanation factors

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Coto, I. [Dept. Fisica Aplicada, University of Huelva, Huelva (Spain)], E-mail: Israel.lopez@dfa.uhu.es; Mas, J.L. [Dept. de Fisica Aplicada I, E.U.P., University of Seville, Seville (Spain); San Miguel, E.G.; Bolivar, J.P. [Dept. Fisica Aplicada, University of Huelva, Huelva (Spain); Sengupta, D. [Department of Geology and Geophysics, I.I.T. Kharagpur, West Bengal (India)

    2009-05-15

    Some radon related parameters have been determined through two different techniques (passive and active) in soil and phosphogypsum samples. Emanation factors determined through these techniques show a good agreement for soil samples while for phosphogympsum samples appear large discrepancies. In this paper, these discrepancies are analyzed and explained if non-controlled radon leakages in the passive technique are taken into account.

  13. EVALUATION OF RADON EMANATION FROM SOIL WITH VARYING MOISTURE CONTENT IN A SOIL CHAMBER

    Science.gov (United States)

    The paper describes measurements to quantitatively identify the extent to which moisture affects radon emanation and diffusive transport components of a sandy soil radon concentration gradient obtained in the EPA test chamber. The chamber (2X2X4 m long) was constructed to study t...

  14. Radon in the DRIFT-II directional dark matter TPC: emanation, detection and mitigation

    CERN Document Server

    Battat, J B R; Daw, E; Dorofeev, A; Ezeribe, A C; Fox, J R; Gauvreau, J -L; Gold, M; Harmon, L J; Harton, J L; Landers, J M; Lee, E R; Loomba, D; Matthews, J A J; Miller, E H; Monte, A; Murphy, A StJ; Paling, S M; Phan, N; Pipe, M; Robinson, M; Sadler, S W; Scarff, A; Snowden-Ifft, D P; Spooner, N J C; Telfer, S; Walker, D; Warner, D; Yuriev, L

    2014-01-01

    Radon gas emanating from materials is of interest in environmental science and also a major concern in rare event non-accelerator particle physics experiments such as dark matter and double beta decay searches, where it is a major source of background. Notable for dark matter experiments is the production of radon progeny recoils (RPRs), the low energy (~100 keV) recoils of radon daughter isotopes, which can mimic the signal expected from WIMP interactions. Presented here are results of measurements of radon emanation from detector materials in the 1 metre cubed DRIFT-II directional dark matter gas time projection chamber experiment. Construction and operation of a radon emanation facility for this work is described, along with an analysis to continuously monitor DRIFT data for the presence of internal 222Rn and 218Po. Applying this analysis to historical DRIFT data, we show how systematic substitution of detector materials for alternatives, selected by this device for low radon emanation, has resulted in a f...

  15. A novel application for 222Rn emanation standards: radon-cryptophane host chemistry.

    Science.gov (United States)

    Laureano-Perez, L; Collé, R; Jacobson, D R; Fitzgerald, R; Khan, N S; Dmochowski, I J

    2012-09-01

    In collaboration with the University of Pennsylvania, a (222)Rn emanation source was used for the determination of the binding affinity of radon to a cryptophane molecular host. This source was similar to a (222)Rn emanation standard that was developed and disseminated by the National Institute of Standards and Technology (NIST). The novel experimental design involved performing the reactions at femtomole levels, developing exacting gravimetric sampling methods and making precise (222)Rn assays by liquid scintillation counting. A cryptophane-radon association constant was determined, K(A)=(49,000±12,000) L mol(-1) at 293 K, which was the first measurement of radon binding to a molecular host.

  16. Influencing effect of heat-treatment on radon emanation and exhalation characteristic of red mud.

    Science.gov (United States)

    Sas, Zoltán; Szántó, János; Kovács, János; Somlai, János; Kovács, Tibor

    2015-10-01

    The reuse of industrial by-products is important for members of numerous industrial sectors. However, though the benefits of reuse are evident from an economical point of view, some compounds in these materials can have a negative effect on users' health. In this study, the radon emanation and exhalation features of red mud were surveyed using heat-treatment (100-1200 °C). As a result of the 1200°C-treated samples, massic radon exhalation capacity reduced from 75 ± 10 mBq kg(-1) h(-1) to 7 ± 4 mBq kg(-1) h(-1), approximately 10% of the initial exhalation rate. To find an explanation for internal structural changes, the porosity features of the heat-treated samples were also investigated. It was found that the cumulative pore volume reduced significantly in less than 100 nm, which can explain the reduced massic exhalation capacity in the high temperature treated range mentioned above. SEM snapshots were taken of the surfaces of the samples as visual evidence for superficial morphological changes. It was found that the surface of the high temperature treated samples had changed, proving the decrement of open pores on the surface.

  17. Optimized measurement of radium-226 concentration in liquid samples with radon-222 emanation.

    Science.gov (United States)

    Perrier, Frédéric; Aupiais, Jean; Girault, Frédéric; Przylibski, Tadeusz A; Bouquerel, Hélène

    2016-06-01

    Measuring radium-226 concentration in liquid samples using radon-222 emanation remains competitive with techniques such as liquid scintillation, alpha or mass spectrometry. Indeed, we show that high-precision can be obtained without air circulation, using an optimal air to liquid volume ratio and moderate heating. Cost-effective and efficient measurement of radon concentration is achieved by scintillation flasks and sufficiently long counting times for signal and background. More than 400 such measurements were performed, including 39 dilution experiments, a successful blind measurement of six reference test solutions, and more than 110 repeated measurements. Under optimal conditions, uncertainties reach 5% for an activity concentration of 100 mBq L(-1) and 10% for 10 mBq L(-1). While the theoretical detection limit predicted by Monte Carlo simulation is around 3 mBq L(-1), a conservative experimental estimate is rather 5 mBq L(-1), corresponding to 0.14 fg g(-1). The method was applied to 47 natural waters, 51 commercial waters, and 17 wine samples, illustrating that it could be an option for liquids that cannot be easily measured by other methods. Counting of scintillation flasks can be done in remote locations in absence of electricity supply, using a solar panel. Thus, this portable method, which has demonstrated sufficient accuracy for numerous natural liquids, could be useful in geological and environmental problems, with the additional benefit that it can be applied in isolated locations and in circumstances when samples cannot be transported.

  18. Dependence of radon emanation of red mud bauxite processing wastes on heat treatment.

    Science.gov (United States)

    Jobbágy, V; Somlai, J; Kovács, J; Szeiler, G; Kovács, T

    2009-12-30

    Natural radioactivity content, radon emanation and some other physical characteristics of red mud were investigated, so that to identify the possibilities of the safe utilization of such material as a building material additive. Based on the radionuclide concentration, red mud is not permitted to be used directly as a building material, however, mixing of a maximum 20% red mud and 80% clay meets the requirements. The main aim of this work was to determine the dependence of the emanation factor of red mud firing temperature and some other parameters. The relevant experimental procedure was carried out in two different ways: without any additional material, and by adding a known amount of sawdust (5-35 wt%) then firing the sample at a given temperature (100-1000 degrees C). The average emanation factor of the untreated dry red mud was estimated to 20%, which decreased to about 5% at a certain heat treatment. Even lower values were found using semi-reductive atmosphere. It has been concluded that all emanation measurements results correlate well to the firing temperature, the specific surface and the pore volume.

  19. Theoretical aspects of the Semkow fractal model in the radon emanation in solids; Aspectos teoricos del modelo fractal de Semkow en la emanacion de radon en solidos

    Energy Technology Data Exchange (ETDEWEB)

    Cruz G, H.S. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    The basic elements of the Fractals theory are developed. The physical basis of radon emission in solids are described briefly. It is obtained that the emanation power E{sub R} of mineral grains is scaled as r{sub 0} {sup D-3} (r{sub 0} : grain radius). From a logarithmic graph E{sub R} versus grain size is deduced the fractal dimension of the emanation surface. The experimental data of different materials give an interval in the fractal dimension D between 2.1 and 2.8 (Author)

  20. Correlation between radon gas emanation and porosity in ornamental stones; Correlacao entre emanacao de gas radonio e porosidade de rochas ornamentais do Estado do Ceara, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, Leiliane Rufina Pereira de; Artur, Antonio Carlos; Bonotto, Daniel Marcos, E-mail: leili_ane@hotmail.com, E-mail: acartur@rc.unesp.br, E-mail: dbonotto@rc.unesp.br [Universidade Estadual Paulista (UNESP), Rio Claro, SP (Brazil); Nogueira Neto, Jose de Araujo, E-mail: nogueira@ufc.br [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Geologia

    2014-01-15

    This article makes correlations between levels of gas {sup 222}Rn emanation and corresponding porosity for thirteen samples of granitic rocks ornamental state of Ceara. For both determinations of physical indexes (bulk density, apparent porosity and water absorption, the levels of U, monitoring emanation of radon gas are made for a period of 25 days in confinement conditions of the samples under vacuum and petrographic studies of the characteristics rocks, with emphasis on the microfissural state. The sampled rocks provided low values of radon gas emanation between U 0,2 ppm and 13.6 ppm. The correlations between the various results show that the microporous network of the rock is determinant in the rate of emanation of radon gas, overlapping, including the influence of own levels of U present in the rocks. The results also show that the amount of radon gas emanating from the rock is small enough compared to the decay caused by the amount of {sup 238}U. The proposition of gas emanating relative to the total generated by rocks ranging between 0.4% and a maximum of 4.2%. (author)

  1. Emanation Study of Gas Radon on the Ancient Cuexcomate Geyser in Puebla City, Mexico

    Directory of Open Access Journals (Sweden)

    J. A. Monarca Serrano

    2016-08-01

    Full Text Available Radon measurements were collected over a period of nine months in the area of the ancient Cuexcomate geyser, in Puebla City. For measuring radon, the passive method of nuclear tracks in solids was used, using polycarbonate CR-39 as radiation sensitive material. Radon concentrations varied in strong anti-correlation with the rainfall intensity. And are lower compared to other locations, in concordance with the stratigraphic composition, as travertine and deposits of volcanic origin, corresponding to the geyser chemical composition and the active environment in the north part of the Trans-Mexican Volcanic Belt with an andesitic and basalt composition.

  2. Seasonal emanation of radon at Ghuttu, northwest Himalaya: Differentiation of atmospheric temperature and pressure influences.

    Science.gov (United States)

    Kamra, Leena

    2015-11-01

    Continuous monitoring of radon along with meteorological parameters has been carried out in a seismically active area of Garhwal region, northwest Himalaya, within the frame work of earthquake precursory research. Radon measurements are carried out by using a gamma ray detector installed in the air column at a depth of 10m in a 68m deep borehole. The analysis of long time series for 2006-2012 shows strong seasonal variability masked by diurnal and multi-day variations. Isolation of a seasonal cycle by minimising short-time by 31 day running average shows a strong seasonal variation with unambiguous dependence on atmospheric temperature and pressure. The seasonal characteristics of radon concentrations are positively correlated to atmospheric temperature (R=0.95) and negatively correlated to atmospheric pressure (R=-0.82). The temperature and pressure variation in their annual progressions are negatively correlated. The calculations of partial correlation coefficient permit us to conclude that atmospheric temperature plays a dominant role in controlling the variability of radon in borehole, 71% of the variability in radon arises from the variation in atmospheric temperature and about 6% of the variability is contributed by atmospheric pressure. The influence of pressure variations in an annual cycle appears to be a pseudo-effect, resulting from the negative correlation between temperature and pressure variations. Incorporation of these results explains the varying and even contradictory claims regarding the influence of the pressure variability on radon changes in the published literature. Temperature dependence, facilitated by the temperature gradient in the borehole, controls the transportation of radon from the deep interior to the surface.

  3. Physical Parameters Affecting the Emanation of RADON-222 from Coal Ash.

    Science.gov (United States)

    Barton, Terence Patrick

    The Rn-222 emanation coefficients for coal ash and parameters which affected them were measured. Samples of ash from both stoker fired and pulverized coal fired boilers were obtained. The stoker ash samples were mechanically separated into size fractions. The pulverized samples were too fine for mechanical sizing and were categorized qualitatively according to origin. Bulk density of the stoker fractions was measured and ranged from .488 to .944 g-cm('-3), increasing as a function of decreasing particle size. Bulk density of the pulverized ash ranged from 1.254 to 1.520 g-cm('-3). Specific gravity of the stoker fractions ranged from 2.017 to 2.390 g-cm('-3), also increasing as a function of decreasing particle size. Specific gravity of the pulverized ash ranged from 2.357 to 2.588 g-cm(' -3). Ra-226 content of the samples was determined by gamma spectrometric analysis of the 352-KeV gamma of Pb -214 and the 609-KeV gamma of Bi-214 from sealed samples of ash. Ra-226 concentrations in the stoker fractions ranged from 11.82 to 16.77 dpm-g('-1), increasing as a function of decreasing particle size. Ra-226 concentrations in the pulverized ash ranged from 6.44 to 7.59 dpm-g(' -1). Scintillation cells were constructed out of commonly available materials and a commercial preparation of ZnS(Ag) scintillator. Emanation chambers which allowed for moderately large sample masses were constructed. The procedure used to measure emanation coefficients was shown to be insensitive to ingrowth time at greater than 3 days ingrowth and relatively insensitive to variations in sample porosity. Emanation coefficients of the stoker fractions were measured at moisture contents of 0, 1.0, 10, 20, and 40 percent by weight. Within each size fraction the emanation coefficient increased as a function of moisture content, ranging from 9.58 x 10('-4) to 4.13 x 10('-2) between 0 and 20 percent moisture, respectively. Emanation coefficients also increased as a function of decreasing particle size

  4. Evaluation of U, Th, K and emanated radon in some NORM and TENORM samples

    Energy Technology Data Exchange (ETDEWEB)

    El Afifi, E.M. [Hot Laboratories and Waste Management Center (HLWMC), Atomic Energy Authority, P.O. Box No. 13759, Cairo (Egypt)]. E-mail: em_afifi@yahoo.com; Hilal, M.A. [Hot Laboratories and Waste Management Center (HLWMC), Atomic Energy Authority, P.O. Box No. 13759, Cairo (Egypt); Khalifa, S.M. [Hot Laboratories and Waste Management Center (HLWMC), Atomic Energy Authority, P.O. Box No. 13759, Cairo (Egypt); Aly, H.F. [Hot Laboratories and Waste Management Center (HLWMC), Atomic Energy Authority, P.O. Box No. 13759, Cairo (Egypt)

    2006-05-15

    Activity concentrations of {sup 226}Ra (of U-series), {sup 228}Ra (of Th-series) and potassium ({sup 40}K) in some heavy minerals and building materials were determined and evaluated in some selected heavy mineral sands and building materials. Three heavy mineral sands (monazite, zircon and black sand) of industrial interest were used. Building materials used here include phosphogypsum (PG) wastes, natural gypsum, ceramics, granite, marble, cement and iron slag wastes associated with iron and steel production. The measurements were carried out using {gamma}-ray spectrometry. The activity concentrations varied widely depending on sample origin. The results indicated that the high activity levels, radium equivalent activity, absorbed-gamma dose rate and effective annual dose rate were found in monazite, zircon and PG wastes as compared to the other materials. The mean activity concentrations in monazite were 40580+/-1370, 182425+/-9870 and 11300+/-9570Bqkg{sup -1} for {sup 238}U, {sup 232}Th and {sup 40}K, respectively. This activity is equivalent to 0.39, 5.1 and 4.5wt% for uranium as U{sub 3}O{sub 8}, thorium as ThO{sub 2} and potassium-40 as K{sub 2}O, respectively. The radium equivalent activity, absorbed-gamma dose rate and effective annual dose rate in monazite were 3.0x10{sup 5}Bqkg{sup -1}, 1.3x10{sup 5}nGyh{sup -1} and 163mSvyr{sup -1}, respectively. The emanation coefficient (EC) of {sup 222}Rn was less than 20%. The average Rn EC was 18% for cement samples and {approx}14% for granite and ceramic samples. It concluded that the Rosetta beach could be considered a valuable source for some metallurgical processes of industrial interest, but with special precautions. Most of the studied building materials can be used without restrictions except PG wastes, granite and ceramic.

  5. Radon emanation based material measurement and selection for the SuperNEMO double beta experiment

    Energy Technology Data Exchange (ETDEWEB)

    Cerna, Cédric, E-mail: cerna@cenbg.in2p3.fr; Soulé, Benjamin; Perrot, Frédéric [Centre d’Études Nucléaires de Bordeaux Gradignan, UMR 5797, F-33170 Gradignan (France)

    2015-08-17

    The SuperNEMO Demonstrator experiment aims to study the neutrinoless double beta decay of 7 kg of {sup 82}Se in order to reach a limit on the light Majorana neutrino mass mechanism T{sub 1/2} (ββ0ν) > 6.5 10{sup 24} years (90%CL) equivalent to a mass sensitivity mβ{sub β} < 0.20 - 0.40 eV (90%CL) in two years of data taking. The detector construction started in 2014 and its installation in the Laboratoire Souterrain de Modane (LSM) is expected during the course of 2015. The remaining level of {sup 226}Ra ({sup 238}U chain) in the detector components can lead to the emanation of {sup 222}Rn gas. This isotope should be controlled and reduced down to the level of a 150 µBq/m{sup 3} in the tracker chamber of the detector to achieve the physics goals. Besides the HPGe selection of the detector materials for their radiopurity, the most critical materials have been tested and selected in a dedicated setup facility able to measure their {sup 222}Rn emanation level. The operating principle relies on a large emanation tank (0.7m{sup 3}) that allows measuring large material surfaces or large number of construction pieces. The emanation tank is coupled to an electrostatic detector equipped with a silicon diode to perform the alpha spectroscopy of the gas it contains and extract the {sup 222}Rn daughters. The transfer efficiency and the detector efficiency have been carefully calibrated through different methods. The intrinsic background of the system allows one to measure 222Rn activities down to 3 mBq, leading to a typical emanation sensitivity of 20 µBq/m{sup 2}/day for a 30 m{sup 2} surface sample. Several construction materials have been measured and selected, such as nylon and aluminized Mylar films, photomultipliers and tracking of the SuperNEMO Demonstrator.

  6. Measurements of size distributions of radon progeny for improved quantification of the lung cancer risk emanating from exposure to radon decay products; Messungen der Groessenverteilungen von Radon-Folgeprodukten zur Verbesserung der Quantifizierung des durch Radonexposition verursachten Lungenkrebsrisikos

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T.

    1997-12-31

    A major issue in radiation protection is to protect the population from the harmful effects of exposure to radon and radon progeny. Quantification of the lung cancer risk emanating from exposure to radon decay products in residential and working environments poses problems, as epidemiologic studies yield information deviating from the results obtained by the indirect method of assessment based on dosimetric respiratory tract models. One important task of the publication here was to characterize the various exposure conditions and to quantify uncertainties that may result from application of the ``dose conversion convention``. A special aerosol spectrometer was therefore designed and built in order to measure the size distributions of the short-lived radon decay products in the range between 0.5 nm and 10 000 nm. The aerosol spectrometer consists of a three-step diffusion battery with wire nets, an 11-step BERNER impactor, and a detector system with twelve large-surface proportional detectors. From the measured size distributions, dose conversion coefficients, E/P{sup eq}, were calculated using the PC software RADEP; the RADEP program was developed by BIRCHALL and JAMES and is based on the respiratory tract model of the ICRP. The E/P{sup eq} coefficients indicate the effective dose E per unit exposure P{sup eq} to radon decay products. (orig./CB) [Deutsch] Eines der groessten Probleme des Strahlenschutzes ist der Schutz der Bevoelkerung vor einer Strahlenexposition durch Radon und seine Folgeprodukte. Die Quantifizierung des Lungenkrebsrisikos, das durch Radonexpositionen in Wohnungen und an Arbeitsplaetzen verursacht wird, ist ein grosses Problem, weil epidemiologische Studien ein anderes Ergebnis liefern, als die indirekte Methode der Abschaetzung mit dosimetrischen Atemtrakt-Modellen. Eine wichtige Aufgabe der vorliegenden Arbeit war es, unterschiedliche Expositionsbedingungen zu charakterisieren und die Unsicherheiten zu quantifizieren, die sich aus der

  7. Measurements of size distributions of radon progeny for improved quantification of the lung cancer risk emanating from exposure to radon decay products; Messungen der Groessenverteilungen von Radon-Folgeprodukten zur Verbesserung der Quantifizierung des durch Radonexposition verursachten Lungenkrebsrisikos

    Energy Technology Data Exchange (ETDEWEB)

    Haninger, T.

    1997-12-31

    A major issue in radiation protection is to protect the population from the harmful effects of exposure to radon and radon progeny. Quantification of the lung cancer risk emanating from exposure to radon decay products in residential and working environments poses problems, as epidemiologic studies yield information deviating from the results obtained by the indirect method of assessment based on dosimetric respiratory tract models. One important task of the publication here was to characterize the various exposure conditions and to quantify uncertainties that may result from application of the ``dose conversion convention``. A special aerosol spectrometer was therefore designed and built in order to measure the size distributions of the short-lived radon decay products in the range between 0.5 nm and 10 000 nm. The aerosol spectrometer consists of a three-step diffusion battery with wire nets, an 11-step BERNER impactor, and a detector system with twelve large-surface proportional detectors. From the measured size distributions, dose conversion coefficients, E/P{sup eq}, were calculated using the PC software RADEP; the RADEP program was developed by BIRCHALL and JAMES and is based on the respiratory tract model of the ICRP. The E/P{sup eq} coefficients indicate the effective dose E per unit exposure P{sup eq} to radon decay products. (orig./CB) [Deutsch] Eines der groessten Probleme des Strahlenschutzes ist der Schutz der Bevoelkerung vor einer Strahlenexposition durch Radon und seine Folgeprodukte. Die Quantifizierung des Lungenkrebsrisikos, das durch Radonexpositionen in Wohnungen und an Arbeitsplaetzen verursacht wird, ist ein grosses Problem, weil epidemiologische Studien ein anderes Ergebnis liefern, als die indirekte Methode der Abschaetzung mit dosimetrischen Atemtrakt-Modellen. Eine wichtige Aufgabe der vorliegenden Arbeit war es, unterschiedliche Expositionsbedingungen zu charakterisieren und die Unsicherheiten zu quantifizieren, die sich aus der

  8. High resolution single particle refinement in EMAN2.1.

    Science.gov (United States)

    Bell, James M; Chen, Muyuan; Baldwin, Philip R; Ludtke, Steven J

    2016-05-01

    EMAN2.1 is a complete image processing suite for quantitative analysis of grayscale images, with a primary focus on transmission electron microscopy, with complete workflows for performing high resolution single particle reconstruction, 2-D and 3-D heterogeneity analysis, random conical tilt reconstruction and subtomogram averaging, among other tasks. In this manuscript we provide the first detailed description of the high resolution single particle analysis pipeline and the philosophy behind its approach to the reconstruction problem. High resolution refinement is a fully automated process, and involves an advanced set of heuristics to select optimal algorithms for each specific refinement task. A gold standard FSC is produced automatically as part of refinement, providing a robust resolution estimate for the final map, and this is used to optimally filter the final CTF phase and amplitude corrected structure. Additional methods are in-place to reduce model bias during refinement, and to permit cross-validation using other computational methods.

  9. On the generation of electric field and infrared radiation in aerosol clouds due to radon emanation in the atmosphere before earthquakes

    Directory of Open Access Journals (Sweden)

    V. A. Liperovsky

    2008-10-01

    Full Text Available The non-stationary Frenkel model of the generator of spikes of the local electric field with time scales of 1–100 min in the atmosphere near seismic fracture regions some days before strong earthqukes is analysed. The model suggests an aerosol cloud, an increased ionisation velocity (e.g. by radon emanation, and an upward flow of air. It was found that during times of earthquake activity (that means a few days before an earthquake, for realistic increases of the ionization intensity of the atmosphere, mosaic-likely occurring and disappearing pulses of local electric fields with intensities of the order of 103−3×103 Vm−1 should be observable. These electric fields would also cause spikes of non-equilibrium IR emissions (0.7–20 μm and local spikes of the magnetic field. The authors propose to perform special complex Earth-based observations of the night-time emissions of the atmosphere in the IR region and of the magnetic as well as quasi-stationary electric fields at some points near to fracture regions in seismo-active belts.

  10. Radon

    Science.gov (United States)

    Exposure to radon is the second leading cause of lung cancer after smoking. Radon is a colorless, odorless, tasteless and invisible gas produced by the decay of naturally occurring uranium in soil and water.

  11. Radon

    Science.gov (United States)

    ... can move to air, groundwater, and surface water. Radon-222 has a radioactive half-life of about 4 ... concerns. The main isotope of health concern is radon-222 ( 222 Rn). Many scientists believe that the alpha ...

  12. Comparison of retrospective and contemporary indoor radon measurements in a high-radon area of Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Zunic, Z.S. [Institute of Nuclear Sciences ' Vinca' , Belgrade (Serbia); Yarmoshenko, I.V. [Institute of Industrial Ecology, Ural Branch of Russian Academy of Sciences, Ekaterinburg (Russian Federation)], E-mail: ivy@ecko.uran.ru; Kelleher, K. [Radiological Protection Institute of Ireland, Dublin (Ireland); Paridaens, J. [SCK.CEN Mol (Belgium); Mc Laughlin, J.P. [School of Physics, University College Dublin (Ireland); Celikovic, I.; Ujic, P. [Institute of Nuclear Sciences ' Vinca' , Belgrade (Serbia); Onischenko, A.D. [Institute of Industrial Ecology, Ural Branch of Russian Academy of Sciences, Ekaterinburg (Russian Federation); Jovanovic, S.; Demajo, A. [Institute of Nuclear Sciences ' Vinca' , Belgrade (Serbia); Birovljev, A. [Radonlab Ltd., Oslo (Norway); Bochicchio, F. [Italian National Institute of Health, Rome (Italy)

    2007-11-15

    In Niska Banja, Serbia, which is a high-radon area, a comparison was made between two retrospective radon measuring methods and contemporary radon measurements. The two retrospective methods derive the radon concentrations that occurred in dwellings over longer periods in the past, based on the amount of trapped {sup 210}Po on the surface of glass objects (surface traps, ST) or in the bulk of porous materials (volume traps, VT). Both surface implanted {sup 210}Po in glass objects and contemporary radon in air were measured in 46 rooms, distributed in 32 houses of this radon spa-town, using a dual alpha track detector configuration (CR-39 and LR115) and CR-39 track etched detectors, respectively. In addition to the use of surface trap measurements, in 18 rooms (distributed in 15 houses) VT samples of suitable material were also collected, allowing to compare ST and VT retrospective radon concentration estimates. For each room, contemporary annual radon concentrations (CONT) were measured or estimated using seasonal correction factors. The distribution of the radon concentration in all data sets was found to be close to lognormal (Chi-square test > 0.05). Geometric means (GM) are similar, ranging from 1040 to 1380 Bq m{sup -3}, whereas geometric standard deviations (GSD) for both the retrospective methods are greater than for the CONT method, showing reasonable agreement between VT, ST and CONT measurements. A regression analysis, with respect to the lognormal distribution of each data set, shows that for VT-ST the correlation coefficient r is 0.85, for VT-CONT r is 0.82 and for ST-CONT r is 0.73. Comparison of retrospective and contemporary radon concentrations with regard to supposed long-term indoor radon changes further supports the principal agreement between the retrospective and conventional methods.

  13. Comparison of retrospective and contemporary indoor radon measurements in a high-radon area of Serbia.

    Science.gov (United States)

    Zunić, Z S; Yarmoshenko, I V; Kelleher, K; Paridaens, J; Mc Laughlin, J P; Celiković, I; Ujić, P; Onischenko, A D; Jovanović, S; Demajo, A; Birovljev, A; Bochicchio, F

    2007-11-15

    In Niska Banja, Serbia, which is a high-radon area, a comparison was made between two retrospective radon measuring methods and contemporary radon measurements. The two retrospective methods derive the radon concentrations that occurred in dwellings over longer periods in the past, based on the amount of trapped (210)Po on the surface of glass objects (surface traps, ST) or in the bulk of porous materials (volume traps, VT). Both surface implanted (210)Po in glass objects and contemporary radon in air were measured in 46 rooms, distributed in 32 houses of this radon spa-town, using a dual alpha track detector configuration (CR-39 and LR115) and CR-39 track etched detectors, respectively. In addition to the use of surface trap measurements, in 18 rooms (distributed in 15 houses) VT samples of suitable material were also collected, allowing to compare ST and VT retrospective radon concentration estimates. For each room, contemporary annual radon concentrations (CONT) were measured or estimated using seasonal correction factors. The distribution of the radon concentration in all data sets was found to be close to lognormal (Chi-square test>0.05). Geometric means (GM) are similar, ranging from 1040 to 1380 Bq m(-3), whereas geometric standard deviations (GSD) for both the retrospective methods are greater than for the CONT method, showing reasonable agreement between VT, ST and CONT measurements. A regression analysis, with respect to the lognormal distribution of each data set, shows that for VT-ST the correlation coefficient r is 0.85, for VT-CONT r is 0.82 and for ST-CONT r is 0.73. Comparison of retrospective and contemporary radon concentrations with regard to supposed long-term indoor radon changes further supports the principal agreement between the retrospective and conventional methods.

  14. Radon in Himalayan springs: a geohydrological control

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M.; Bartarya, S.K. [Wadia Inst. of Himalayan Geology, Dehra Dun (India); Ramola, R.C. [Garhwal Univ., Srinagar, Uttar Pradesh (India). Dept. of Physics

    2000-04-01

    This paper presents the results of radon measurements in springs of the Himalayan region by using radon emanometry technique. The radon was measured in different springs, draining from different geohydrological setups, and from stream water in order to find the geohydrological control over radon concentration in groundwater emanating in the form of spring. The radon values were found to vary from 0.4 Bq/l to 887 Bq/l, being observed lowest for a turbulent stream and highest for the spring. The radon values were recorded highest in the springs draining through gneiss, granite, mylonite, etc. Radon concentrations have been related with four spring types viz. fracture-joint related spring, fault-lineament related spring, fluvial related spring and colluvial related spring, showing geohydrological characteristics of the rocks through which they are emanating. The high radon concentration in fracture-joint and fault-lineament springs is related to increased ratio of rock surface area to water volume and uranium mineralisation in the shear zones present in the close vicinity of fault and thrust. The low concentration of radon in fluvial and colluvial springs is possibly because of high transmissivity and turbulent flow within such deposits leading to natural de-emanation of gases. (orig.)

  15. Radon metrology

    Energy Technology Data Exchange (ETDEWEB)

    Naismith, S.; Howarth, C. [National Radiological Protection Board, Chilton (United Kingdom)

    1996-09-01

    NRPB carries out calibrations of various types of radon and radon decay product measurement systems for its own purposes and for laboratories throughout Europe. There are currently two radon calibration facilities at NRPB: a 43 m{sup 3} radon chamber and the Fast Radon Exposure Device (FRED), a sealed steel drum. The radon chamber is used for active radon detection systems and the calibration of large numbers of passive detectors. Fred has a high radon concentration and is used to calibrate small numbers of passive radon gas detectors in a short period. (Author).

  16. Radon exhalation from building materials used in Libya

    Science.gov (United States)

    Saad, A. F.; Al-Awami, Hend H.; Hussein, N. A.

    2014-08-01

    Radon exhalation rates have been determined for various different samples of domestic and imported building materials available in the Libyan market for home construction and interior decoration. Radon exhalation rates were measured by the sealed-can technique based on CR-39 nuclear track detectors (NTDs). The results show that radon exhalation rates from some imported building materials used as foundations and for decoration are extremely high, and these samples are the main sources of indoor radon emanation. Radium contents and annual effective doses have also been estimated.

  17. Measurements of radon around closed uranium mines

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Sadaaki E-mail: furuta@ningyo.jnc.go.jp; Ito, Kimio; Ishimori, Yuu

    2002-07-01

    There are several waste rock yards at closed uranium mines around Ningyo-toge, in the Western Honshu Island of Japan, and measurements of radon were carried out by both the passive method and the sampling method around these yards. As comparatively high radon concentrations were observed in two districts through routine measurements, more detailed measurements were made by the passive method in these districts. The impact of radon emanation from the waste rock yards was small for both residential districts and around these yards when considering the natural background level of radon. In addition, by simultaneous continuous measurements of radon and its progeny at two locations, it was estimated that the effective dose caused by the representative uranium waste rock yards was less than the public effective dose limit of 1 mSv year{sup -1} at the fenced boundary of the waste rock site.

  18. High-resolution radon monitoring and hydrodynamics at Mount Vesuvius

    Science.gov (United States)

    Cigolini, Corrado; Salierno, Francesco; Gervino, Gianpiero; Bergese, Paolo; Marino, Ciro; Russo, Massimo; Prati, Paolo; Ariola, Vincenzo; Bonetti, Roberto; Begnini, Stefania

    A yearlong high-resolution radon survey has been carried on at Mount Vesuvius, starting in May 1998. Radon activities were acquired by exposing charcoal canisters and track-etch detectors. Sampling stations were deployed along two major summit faults and around the caldera bottom. Volcanically-related earthquakes, with MD ≥ 2.5, may be discriminated from regional seismic events since their cumulative radon anomalies are recorded from stations located along all the above structural features. On the contrary, radon anomalies correlated to regional earthquakes, with MD ≥ 4, are essentially recorded by the sampling sites located along the two summit faults (whose roots extend deeper into the Tertiary basement rocks that underlay the volcano). Radon migration to the surface is ruled by convection within a porous medium of relatively low porosity (ϕ ≈ 10-5), suggesting that fluid motion is strongly localised along fractures. It is suggested that fluid pressure build up, followed by fluid release and migration during incipient fracturing of the porous medium, precede the onset of volcanically-induced earthquakes.

  19. Systematic effects in radon mitigation by sump/pump remediation

    Energy Technology Data Exchange (ETDEWEB)

    Groves-Kirkby, C.J.; Denman, A.R. [Northampton General Hospital, Medical Physics Dept. (United Kingdom); Groves-Kirkby, C.J.; Woolridge, A.C. [Northampton Univ., School of Health (United Kingdom); Woolridge, A.C.; Phillips, P.S.; Crockett, R.G.M. [Northampton Univ., School of Applied Sciences (United Kingdom); Tornberg, R. [Radon Centres Ltd., Grove Farm, Moulton, Northampton (United Kingdom)

    2006-07-01

    Sump/Pump remediation is widely used in the United Kingdom to mitigate indoor radon gas levels in residential properties. To quantify the effectiveness of this technology, a study was made of radon concentration data from a set of 173 homes situated in radon Affected Areas in and around Northamptonshire, U.K., re-mediated using conventional sump/pump tology. This approach is characterised by a high incidence of satisfactory mitigation outcomes, with more than 75% of the sample exhibiting mitigation factors (defined as the ratio of radon concentrations following and prior to remediation) of 0.2 or better. There is evidence of a systematic trend, where houses with higher initial radon concentrations have higher mitigation factors, suggesting that the total indoor radon concentration within a dwelling can be represented by two components, one susceptible to mitigation by sump/pump remediation, the other remaining essentially unaffected by these remediation strategies. The first component can be identified with ground-radon emanating from the subsoil and bedrock geologies, percolating through the foundations of the dwelling as a component of the soil-gas, potentially capable of being attenuated by sump/pump or radon-barrier remediation. The second contribution is attributed to radon emanating from materials used in the construction of the dwelling, principally concrete and gypsum plaster-board, with a further small contribution from the natural background level, and is essentially unaffected by ground-level remediation strategies. Modelling of such a two-component radon dependency using realistic ground-radon attenuation factors in conjunction with typical structural-radon levels yields behaviour in good agreement with the observed inverse-power dependence of mitigation factor on initial radon concentration. (authors)

  20. Polycarbonates: a long-term highly sensitive radon monitor

    CERN Document Server

    Pressyanov, D; Poffijn, A; Meesen, G; Deynse, A V

    2000-01-01

    An approach for long-term (either retrospective or prospective) sup 2 sup 2 sup 2 Rn measurements is proposed that is based on the combination of the high radon absorption ability of some polycarbonates with their alpha track-etch properties. The detection limit is projected to be <10 Bq m sup - sup 3 for an exposure time of 20 yr.

  1. sup 2 sup 2 sup 6 Ra measurement in Mo, Cd and Nd sub 2 O sub 3 samples with the emanation method

    CERN Document Server

    Barabash, A S; Kornoukhov, V N; Orekhov, I V

    2001-01-01

    Measurements of sup 2 sup 2 sup 6 Ra content in materials and chemical reagents used to construct the double beta decay sources in the NEMO-3 experiment have been done with the emanation method technique. Three different radon emanation technologies were used in these studies. The first was the 'traditional' method of dissolving the sample. The second was an extraction of Rn from a melted sample and finally a technique of heating fine-grained powder was used. It is shown that there is good agreement of the data received with the emanation method and low background high purity germanium detectors. The sensitivity of this method is 0.02 mBq/l of solution (for the 'standard' emanation method) or 0.02 mBq/kg (for methods in which radon is extracted from a powder or melt).

  2. Radon as a groundwater tracer in Forsmark and Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Grolander, Sara

    2009-10-15

    caused by the homogenous radon concentrations measured in the Laxemar area. The radon concentrations in near surface water measured in Forsmark showed large variability with both low and high radon concentrations. This large variability in radon concentration could not be explained by the flow pattern of the groundwater since no clear correlation between radon concentration and recharge/discharge classification was found. The radon concentration was also measured at different depths in the soil profile at three locations in the Forsmark area. The results showed large differences with increasing radon concentration with increasing depth. This gradient of radon concentration can be explained largely by the radon emanation potential of the local soil type at different depths. High radon concentrations were found in wells with higher radon emanation potential like till and bedrock. These observations showed the importance of the radon emanation potential of the local soil for the radon concentration in groundwater. The main purpose of this study has been to evaluate the use of radon as a tracer for groundwater flow patterns. The method is based on the ingrowth of radon from its progenitor radium according to the law of radioactive decay. According to this law the radon concentration in groundwater will reach equilibrium conditions after approximately 30 days in contact with the surrounding soil. The equilibrium radon concentration of the near surface groundwater was measured at several location in the Forsmark area and a range of the steady state radon concentration was calculated. The measured steady state radon concentration was then used to evaluate the radon concentrations measured in near surface groundwater in the area. A recharge/discharge classification of the wells was done based on the range of steady state radon concentration and the measured radon concentrations in groundwater. All wells with radon concentration below the steady state radon concentration were

  3. A comparison of contemporary and retrospective radon gas measurements in high radon dwellings in Ireland

    Energy Technology Data Exchange (ETDEWEB)

    Kelleher, K.; McLaughlin, J.P. [University College Dublin (Ireland); Fenton, D.; Colgan, P.A. [Radiological Protection Institute of Ireland, Dublin (Ireland)

    2006-07-01

    Little correlations has been found between contemporary radon gas measurements made in the past and retrospective radon gas measurements in Irish dwellings. This would suggest that these two techniques would result in two significantly different cumulative radon exposure estimates. Contemporary radon gas measurements made a few years apart in the same room of a dwelling were found to be significantly different. None of these differences could be explained by known changes to the rooms themselves., such ventilation or structural alterations to the room. This highlights the limitations of the contemporary radon gas measurements as a surrogate measurement for use in residential radon epidemiology. The contemporary radon gas measurements made by the Radiological Protection Institute of Ireland (R.P.I.I.) and University College of Dublin (U.C.D.) do not cover the same exposure period as the retrospective estimates and so the accuracy of the retrospective measurements cannot be demonstrated. A weak correlation can be seen between the retrospective radon gas estimates and a combination of the two contemporary radon gas estimates. It is not unreasonable to expect improvement in the correlation if further contemporary radon gas measurements were made in these rooms. (N.C.)

  4. Identifying areas with potential for high indoor radon levels: analysis of the national airborne radiometric reconnaissance data for California and the Pacific Northwest

    Energy Technology Data Exchange (ETDEWEB)

    Moed, B.A.; Nazaroff, W.W.; Nero, A.V.; Schwehr, M.B.; Van Heuvelen, A.

    1984-04-01

    Radon-222 is an important indoor air pollutant which, through the inhalation of its radioactive decay products, accounts for nearly half of the effective dose equivalent to the public from natural ionizing radiation. Indoor radon concentrations vary widely, largely because of local and regional differences in the rate of entry from sources. The major sources are soil and rock near building foundations, earth-based building materials, and domestic water; of these, soil and rock are thought to be predominant in many buildings with higher-than-average concentrations. Thus, one key factor in determining radon source potential is the concentration of radium, the progenitor of radon, in surficial rocks and soils. Aerial radiometric data were analyzed, collected for the National Uranium Resource Evaluation Program, for seven Western states to: (1) provide information on the spatial distribution of radium contents in surficial geologic materials for those states; and (2) investigate approaches for using the aerial data, which have been collected throughout the contiguous United States and Alaska, to identify areas where high indoor radon levels may be common. Radium concentrations were found to be relatively low in central and western portions of Washington, Oregon, and northern California; they were found to be relatively high in central and southern California. A field validation study, conducted along two flight-line segments near Spokane, Washington, showed close correspondence between the aerial data, in situ measurements of both radium content and radon flux from soil, and laboratory measurements of both radium content of and radon emanation rate from soil samples. 99 references, 11 figures, 3 tables.

  5. Preliminary results regarding the first map of residential radon in some regions in Romania.

    Science.gov (United States)

    Cosma, C; Cucoş Dinu, A; Dicu, T

    2013-07-01

    Radon represents the most important contribution of population exposure to natural ionising radiation. This article presents the first indoor radon map in some regions of Romania based on 883 surveyed buildings in the Ştei-BăiŢa radon-prone region and 864 in other regions of Romania. Indoor radon measurements were performed in the last 10 y by using CR-39 nuclear track detectors exposed for 3-12 months on ground floor levels of dwellings. Excluding the Ştei-BăiŢa radon-prone region, an average indoor radon concentration of 126 Bq m(-3) was calculated for Romanian houses. In the Ştei-BăiŢa radon-prone area, the average indoor concentration was 292 Bq m(-3). About 21 % of the investigated dwellings in the Ştei-BăiŢa radon-prone region exceed the threshold of 400 Bq m(-3), while 5 % of the dwellings in other areas of Romania exceed the same threshold. As expected, indoor radon concentration is not uniformly distributed throughout Romania. The map shows a high variability among surveyed regions, mainly due to the differences in geology. The radon emanation rate is substantially influenced by the soil characteristics, such as the soil permeability and soil gas radon concentration. Since higher permeability enables the increased migration of soil gas and radon from the soil into the building, elevated levels of indoor radon can be expected in more permeable soil environments.

  6. Radon variability in borehole from Multi-Parametric Geophysical Observatory of NW Himalaya in relation to meteorological parameters.

    Science.gov (United States)

    Kamra, Leena; Choubey, V M; Kumar, Naresh; Rawat, Gautam; Khandelwal, D D

    2013-02-01

    Radon has been measured continuously at an interval of 15 min at 10 m depth in a 68 m deep borehole. Five years of high resolution data of radon sampled at 15 min shows a complex trend with strong seasonal and diurnal trends. This temporal variation of radon has high emanation during summer and low concentration in winter. Diurnal radon variability was observed mainly during March-June and September-November each year. The existence of these diurnal periodicities in radon is related to the borehole temperature gradient i.e. difference between external atmospheric and internal borehole temperature at 10 m depth in the air column. The measured radon values are characterized by a diurnal cycle with a maximum in the afternoon and a minimum in the morning in all the seasons except in winter and during rainy periods. Minimum radon variations are recorded in the winter months primarily in December and January. Sudden unsystematic jumps in radon counts are observed each year in the rainy period (July and August). The atmospheric temperature was found to positively correlate with radon emanation. The data set of the borehole indicates a good correlation between atmospheric temperature and radon concentration that is observed throughout the year except in the rainy season. The spectra of radon and atmospheric temperature time series of 5 years data clearly show prominent and clear peaks at 1 and 2 cycles per day.

  7. 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.

  8. The effects of high ambient radon on thermoluminescence dosimetry readings.

    Science.gov (United States)

    Harvey, John A; Kearfott, Kimberlee J

    2011-11-01

    The effect of a high level of ambient (222)Rn gas on thermoluminescence dosemeters (TLDs) is examined. Groups of LiF:Mg,Ti and CaF(2):Dy TLDs were exposed to (222)Rn under controlled environmental conditions over ∼7 d using a luminous (226)Ra aircraft dial. LiF:Mg,Ti TLDs were tested bare, and both types were tested mounted in cards used for environmental dosimetry and mounted in cards enclosed in plastic badges. A passive continuous radon monitor was used to measure the (222)Rn level in the small chamber during the experiments. The data were analysed to determine the relationship between the integrated (222)Rn level and the TLD response. Although both LiF:Mg,Ti and CaF(2):Dy TLDs showed a strong response to (222)Rn, the badges prevented measurable radon detection by the TLDs within. The TLDs were not used to directly measure the radon concentration; rather, a correction for its influence was desired.

  9. Radon exhalation rate from soil samples of South Kumaun Lesser Himalayas, India

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Yogesh; Prasad, Ganesh; Gusain, G.S. [Department of Physics, H.N.B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal 249 199 (India); Choubey, V.M. [Wadia Institute of Himalayan Geology, Dehradun 248 001 (India); Ramola, R.C. [Department of Physics, H.N.B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal 249 199 (India)], E-mail: rcramola@gmail.com

    2008-08-15

    Ionizing radiation exposure experienced by the general population is mainly due to the indoor radon. Major part of radon comes from the top layer of the earth. The radon emanation is associated with radon in soil and sleepy back radium in the soil. Both field and laboratory measurements were carried out for the instantaneous and integrated radon concentration in soil-gas. The radon exhalation rate from collected soil samples was measured using LR-115 Type II plastic track detector. The soil-gas radon concentration was measured with the help of radon Emanometry method. The effective radium content of the soil samples was also calculated. The correlation coefficient between radium contents in collected soil samples and soil-gas radon from the same locations was calculated as 0.1, while it is 0.2 between radon exhalation rate and soil-gas radon concentration. The results show weak positive correlation due to the geological disturbance in the equilibrium conditions and high mobility of radon in the same geological medium.

  10. The use of SSNTDs in the retrospective assessment of radon exposure in high radon rural communities in Yugoslavia

    CERN Document Server

    Zunic, Z S; Walsh, C; Benderac, R

    1999-01-01

    A description is given of the field application of a technique using CR-39 and LR 115 detectors to determine alpha recoil implanted sup 2 sup 1 sup 0 Po surface activity on domestic glass artefacts in dwellings. These investigations took place in two small stable rural communities in uraniferous areas of Yugoslavia where between 32% and 74% of contemporary indoor radon levels were found to be above the commonly used Action Level of 200 Bq m sup - sup 3 and individual levels as high as 8700 Bq m sup - sup 3 were measured. The sup 2 sup 1 sup 0 Po data is used to retrospectively estimate radon exposures in these communities. Comparisons between the retrospectively estimated radon exposures and those being received at present are made.

  11. Functional test of a Radon sensor based on a high-resistivity-silicon BJT detector

    Energy Technology Data Exchange (ETDEWEB)

    Dalla Betta, G.F., E-mail: dallabe@disi.unitn.it [DISI, Università di Trento, and INFN Trento, Trento (Italy); RSens srl, Modena (Italy); Tyzhnevyi, V. [DISI, Università di Trento, and INFN Trento, Trento (Italy); Bosi, A.; Bonaiuti, M. [RSens srl, Modena (Italy); Angelini, C.; Batignani, G.; Bettarini, S.; Bosi, F.; Forti, F.; Giorgi, M.A.; Morsani, F.; Paoloni, E.; Rizzo, G.; Walsh, J. [Dipartimento di Fisica, Università di Pisa, and INFN Pisa, Pisa (Italy); Lusiani, A. [Scuola Normale Superiore and INFN Pisa, Pisa (Italy); Ciolini, R.; Curzio, G.; D' Errico, F.; Del Gratta, A. [Dipartimento di Ingegneria Meccanica, Nucleare e della Produzione, Università di Pisa, Pisa (Italy); Bidinelli, L. [En and tech, Università di Modena e Reggio Emilia, Reggio Emilia (Italy); RSens srl, Modena (Italy); and others

    2013-08-01

    A battery-powered, wireless Radon sensor has been designed and realized using a BJT, fabricated on a high-resistivity-silicon substrate, as a radiation detector. Radon daughters are electrostatically collected on the detector surface. Thanks to the BJT internal amplification, real-time α particle detection is possible using simple readout electronics, which records the particle arrival time and charge. Functional tests at known Radon concentrations, demonstrated a sensitivity up to 4.9 cph/(100 Bq/m{sup 3}) and a count rate of 0.05 cph at nominally-zero Radon concentration.

  12. Radon survey in the high natural radiation region of Niska Banja, Serbia.

    Science.gov (United States)

    Zunic, Z S; Yarmoshenko, I V; Birovljev, A; Bochicchio, F; Quarto, M; Obryk, B; Paszkowski, M; Celiković, I; Demajo, A; Ujić, P; Budzanowski, M; Olko, P; McLaughlin, J P; Waligorski, M P R

    2007-01-01

    A radon survey has been carried out around the town of Niska Banja (Serbia) in a region partly located over travertine formations, showing an enhanced level of natural radioactivity. Outdoor and indoor radon concentrations were measured seasonally over the whole year, using CR-39 diffusion type radon detectors. Outdoor measurements were performed at 56 points distributed over both travertine and alluvium sediment formations. Indoor radon concentrations were measured in 102 living rooms and bedrooms of 65 family houses. In about 50% of all measurement sites, radon concentration was measured over each season separately, making it possible to estimate seasonal variations, which were then used to correct values measured over different periods, and to estimate annual values. The average annual indoor radon concentration was estimated at over 1500 Bq/m3 and at about 650 Bq/m3 in parts of Niska Banja located over travertine and alluvium sediment formations, respectively, with maximum values exceeding 6000 Bq/m3. The average value of outdoor annual radon concentration was 57 Bq/m3, with a maximum value of 168 Bq/m3. The high values of indoor and outdoor radon concentrations found at Niska Banja make this region a high natural background radiation area. Statistical analysis of our data confirms that the level of indoor radon concentration depends primarily on the underlying soil and building characteristics.

  13. Radon survey in the high natural radiation region of Niska Banja, Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Zunic, Z.S. [Institute of Nuclear Sciences ' Vinca' , P.O. Box 522, 11000 Belgrade (Serbia); Yarmoshenko, I.V. [Institute of Industrial Ecology, Ural Branch of Russian Academy of Sciences Ekaterinburg (Russian Federation)]. E-mail: ivy@ecko.uran.ru; Birovljev, A. [Radonlab Ltd., Akersveien 24C, 0177 Oslo (Norway); Bochicchio, F. [Istituto Superiore di Sanita - Italian National Institute of Health, Department of Technology and Health, Rome (Italy); Quarto, M. [Istituto Superiore di Sanita - Italian National Institute of Health, Department of Technology and Health, Rome (Italy); Obryk, B. [Institute of Nuclear Physics (IFJ), Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); Paszkowski, M. [Institute of Geological Sciences, Polish Academy of Sciences, Senacka 1, 31-342 Cracow (Poland); Celikovic, I. [Institute of Nuclear Sciences ' Vinca' , P.O. Box 522, 11000 Belgrade (Serbia); Demajo, A. [Institute of Nuclear Sciences ' Vinca' , P.O. Box 522, 11000 Belgrade (Serbia); Ujic, P. [Institute of Nuclear Sciences ' Vinca' , P.O. Box 522, 11000 Belgrade (Serbia); Budzanowski, M. [Institute of Nuclear Physics (IFJ), Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); Olko, P. [Institute of Nuclear Physics (IFJ), Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); McLaughlin, J.P. [University College Dublin, Belfield, Dublin 4 (Ireland); Waligorski, M.P.R. [Institute of Nuclear Physics (IFJ), Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); Maria Sklodowska-Curie Memorial Centre of Oncology, Cracow (Poland)

    2007-07-01

    A radon survey has been carried out around the town of Niska Banja (Serbia) in a region partly located over travertine formations, showing an enhanced level of natural radioactivity. Outdoor and indoor radon concentrations were measured seasonally over the whole year, using CR-39 diffusion type radon detectors. Outdoor measurements were performed at 56 points distributed over both travertine and alluvium sediment formations. Indoor radon concentrations were measured in 102 living rooms and bedrooms of 65 family houses. In about 50% of all measurement sites, radon concentration was measured over each season separately, making it possible to estimate seasonal variations, which were then used to correct values measured over different periods, and to estimate annual values. The average annual indoor radon concentration was estimated at over 1500 Bq/m{sup 3} and at about 650 Bq/m{sup 3} in parts of Niska Banja located over travertine and alluvium sediment formations, respectively, with maximum values exceeding 6000 Bq/m{sup 3}. The average value of outdoor annual radon concentration was 57 Bq/m{sup 3}, with a maximum value of 168 Bq/m{sup 3}. The high values of indoor and outdoor radon concentrations found at Niska Banja make this region a high natural background radiation area. Statistical analysis of our data confirms that the level of indoor radon concentration depends primarily on the underlying soil and building characteristics.

  14. Development of a highly sensitive radon-222 amplifier (HiSRA) for low-level atmospheric measurements.

    Science.gov (United States)

    Topin, Sylvain; Richon, Patrick; Thomas, Vincent; Gréau, Claire; Pujos, Julie; Moulin, Julien; Hovesepian, Alexandre; Deliere, Ludovic

    2017-05-01

    Radon ((222)Rn), a radioactive gas with a half-life of 3.82 days, is continuously emanated from soil, rocks, and water by the radioactive decay of (226)Ra. Radon-222 is released from the ground into the atmosphere, where it is transported mainly by turbulent diffusion or convection. For precise measurement of radon-222 atoms in the atmosphere, the detectors typically used present a small volume or surface area and are therefore not very sensitive, especially for online measurements and short sample intervals (Radon Amplifier (HiSRA) consisting in an enrichment system placed prior to a classic radon-222 analyzer. This system uses permeation membranes that make it possible to treat large quantities of air online (30 m(3) h(-1)). The radon-222 concentration is increased instantaneously by at least a factor of 30 across the HiSRA system. Therefore, in this study, when coupling to an ionization chamber (AlphaGUARDTM) at the outlet of the HiSRA system, the detection limit of the overall system is multiplied by factor of 30 and induces a new LD for a radon 222 gas analyzer lower than 1 Bq m(-3) for an integrating time of 10 min and 0.1 Bq m(-3) for 1 h. We constructed one radon amplifier prototype that provided the preliminary results for amplification efficiency and the initial measurements presented herein. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Soil radon dynamics in the Amer fault zone: An example of very high seasonal variations.

    Science.gov (United States)

    Moreno, V; Bach, J; Font, Ll; Baixeras, C; Zarroca, M; Linares, R; Roqué, C

    2016-01-01

    Soil radon levels of the Amer fault zone have been measured for a 4 year-period with the aim of checking seasonal fluctuations obtained in previous studies and to understand radon origin and dynamics. In this manuscript additional results are presented: updated continuous and integrated soil radon measurements, radionuclide content of soil materials and a detailed analysis of an urban profile by means of the electrical resistivity imaging technique and punctual soil radon, thoron and CO2 measurements. Integrated and continuous measurements present a wide range of values, [0.2-151.6] kBq m(-3) for radon, [4.5-39.6] kBq m(-3) for thoron and [4.0-71.2] g m(-2) day(-1) for CO2. The highest soil radon levels in the vicinity of the Amer fault (>40 kBq m(-3)) are found close to the fractured areas and present very important fluctuations repeated every year, with values in summer much higher than in winter, confirming previous studies. The highest radon values, up to 150 kBq m(-3), do not have a local origin because the mean value of radium concentration in this soil (19 ± 5 Bq kg(-1)) could not explain these values. Then soil radon migration through the fractures, influenced by atmospheric parameters, is assumed to account for such a high seasonal fluctuation. As main conclusion, in fractured areas, seasonal variations of soil radon concentration can be very important even in places where average soil radon concentration and radium content are not especially high. In these cases the migration capability of the soil is given not by intrinsic permeability but by the fracture structure. Potential risk estimation based on soil radon concentration and intrinsic permeability must be complemented with geological information in fractured systems.

  16. Development of a high efficiency personal/environmental radon dosimeter using polycarbonate detectors.

    Science.gov (United States)

    Taheri, M; Jafarizadeh, M; Baradaran, S; Zainali, Gh

    2006-12-01

    Passive radon dosimeters, based on alpha particle etched track detectors, are widely used for the assessment of radon exposure. These methods are often applied in radon dosimetry for long periods of time. In this research work, we have developed a highly efficient method of personal/environmental radon dosimetry that is based upon the detection of alpha particles from radon daughters, (218)Po and (214)Po, using a polycarbonate detector (PC). The radon daughters are collected on the filter surface by passing a fixed flow of air through it and the PC detector, placed at a specified distance from the filter, is simultaneously exposed to alpha particles. After exposure, the latent tracks on the detector are made to appear by means of an electrochemical etching process; these are proportional to the radon dose. The air flow rate and the detector-filter distance are the major factors that can affect the performance of the dosimeter. The results obtained in our experimental investigations have shown that a distance of 1.5 cm between the detector and the filter, an absorber layer of Al with a thickness of 12 microm and an air flow rate of 4 l min(-1) offer the best design parameters for a high efficiency radon dosimeter. Then, the designed dosimeter was calibrated against different values of radon exposures and the obtained sensitivity was found to be 2.1 (tracks cm(-2)) (kBq h m(-3))(-1). The most important advantages of this method are that it is reliable, fast and convenient when used for radon dose assessment. In this paper, the optimized parameters of the dosimeter structure and its calibration procedure are presented and discussed.

  17. XENON1T radon assay

    Energy Technology Data Exchange (ETDEWEB)

    Bruenner, Stefan [MPIK, Heidelberg (Germany); Collaboration: XENON-Collaboration

    2016-07-01

    The radioactive isotope {sup 222}Rn is one of the most dominant intrinsic background sources for experiments dealing with a low event rate like the XENON1T Dark Matter detector. Being part of the primordial decay chain of {sup 238}U the noble gas {sup 222}Rn permanently emanates from almost all materials. Therefore, it is crucial to determine the radon emanation rate of those detector components that will be in contact with the xenon target. The technique of the radon emanation measurements, making use of ultra low background proportional counters is presented as well as selected results for XENON1T.

  18. Application of activated charcoal radon collectors in high humidity environments

    Energy Technology Data Exchange (ETDEWEB)

    Iimoto, Takeshi E-mail: iimoto@rcnst.u-tokyo.ac.jp; Tokonami, Shinji; Morishita, Yasuaki; Kosako, Toshiso

    2004-09-01

    Most commercially based activated charcoal radon collectors were designed for use in indoor environments. However, at present, they are often used for research in radon surveys in unique environments, such as in the bathrooms, underground areas, mines, caves and tunnels. In these environments, the relative humidity would be around 100%, and a change in the sensitivity of cpm(Bq m{sup -3}){sup -1}(radon) would occur. For this study, the reduction in the sensitivity of activated charcoal radon collector due to environmental humidity was investigated, and the data correction was discussed. Here, ST-100 (Pico-Rad) was selected as an example of a familiar activated charcoal radon collector. According to our performance test, the humidity of 90% (20 deg. C) resulted in a 15% reduction of the sensitivity for 24 h collection. The ST-100 user should discuss the necessity of data correction by comparing the change of sensitivity with other levels of estimation errors.

  19. Application of activated charcoal radon collectors in high humidity environments.

    Science.gov (United States)

    Iimoto, Takeshi; Tokonami, Shinji; Morishita, Yasuaki; Kosako, Toshiso

    2005-01-01

    Most commercially based activated charcoal radon collectors were designed for use in indoor environments. However, at present, they are often used for research in radon surveys in unique environments, such as in the bathrooms, underground areas, mines, caves and tunnels. In these environments, the relative humidity would be around 100%, and a change in the sensitivity of cpm(Bq m(-3))(-1)(radon) would occur. For this study, the reduction in the sensitivity of activated charcoal radon collector due to environmental humidity was investigated, and the data correction was discussed. Here, ST-100 (Pico-Rad) was selected as an example of a familiar activated charcoal radon collector. According to our performance test, the humidity of 90% (20 degrees C) resulted in a 15% reduction of the sensitivity for 24 h collection. The ST-100 user should discuss the necessity of data correction by comparing the change of sensitivity with other levels of estimation errors.

  20. Geology and geochemistry of radon in shear zones: End of year progress report

    Energy Technology Data Exchange (ETDEWEB)

    Gundersen, L.C.S.; Schultz, A.P.; Wanty, R.B.; Gates, A.E.; Crespi, J.M.

    1989-01-01

    The objective of this project is to understand the geology of radon gas behavior in areas where shared fault zones cause localized, anomalously high concentrations of radon. Sheared fault zones in bedrock have been identified as the cause of some of the highest indoor radon and water borne radon problems recorded in the United States. This study will provide detailed geological and geochemical models of the processes that create high concentration of radon in shear zones. The main research goals are to: (1) characterize and quantify uranium enrichment in shear zones by examining the chemical and deformational processes involved; (2) develop predictive models that will identify severe radon occurrences by rock type, amount of deformation (shear strain), deformational style, and amount of radionuclide enrichment; (3) characterize and quantify the effect of deformation on the development of soils, permeability, radon migration and emanation, alteration, and radium distribution; (4) characterize and quantify the rock-water equilibria within shear zones that produce the extreme concentrations of radon in water derived from sheared rock aquifers, and examine the contribution of radon in water to indoor radon concentrations. 4 refs.

  1. Radon in the water from drilled wells. Results from an investigation in Oerebro; Radon i vatten fraan bergborrade brunnar. Resultat fraan en undersoekning i oerebro kommun

    Energy Technology Data Exchange (ETDEWEB)

    Liden, E.; Andersson, Lennart [Regionsjukhuset, Oerebro (Sweden). Yrkes- och miljoemedicinska kliniken; Linden, A. [Svensk Geofysik AB, Falun (Sweden); Aakerblom, G. [Statens Straalskyddsinstitut, Stockholm (Sweden); Aakesson, T. [Miljoe- och haelsoskyddsfoervaltningen, Oerebro (Sweden)

    1995-09-01

    In 1991 a drilled well containing water with a radon count of about 20,000 Bq/l was found in the city of Oerebro in southern Sweden. A study was started to develop measures to decrease the radon content of water, investigate public health risks and determine the prevalence of high-radon waters in Sweden. 1991-94 various techniques were tested to reduce the concentration of radon in water. The efficiency of aerating high-radon drinking water was studied under field conditions using two modified aerators in a well, in a pressure tank, and in a column of pellets. The efficiency varied from 20 to 99%. A survey of radon in water from 269 drilled wells was conducted in the Municipality of Oerebro. In water from 78 wells, the mean concentration of radon was 1336 Bq/l. The emanation of radon during normal household activities was studied in a home supplied with water from a drilled well whose radon count was approx 20,000 Bq/l. A geological investigation revealed the presence of thin Uranium-loaded fissures in the bedrock (granite) surrounding the well. 130 refs, 16 figs, 14 tabs.

  2. Identification of high radon areas with passive methods and geological assessments in some Italian regions

    Science.gov (United States)

    Rossetti, Marta; Bartolomei, Paolo; Esposito, Massimo; Marrocchino, Elena; Vaccaro, Carmela

    2010-05-01

    geological knowledge of the high concentration macro-areas identified in this work in order to better determine them. This study has allowed to point out not negligible radon concentrations also in traditionally no-risk zone; moreover the application of the developed methodology will be useful to give advices in order to fill Italian legislation gaps or to draft urban development plans. In particular, the correlation between radon concentrations and some geological features has been proved in Lombardia and some hypothesis have been formulated to understand the geological origin of the radon source. The high radon concentrations in the North of the Region are related to the high uranium content in different rock types distributed in these areas. For the flat area in correspondence of the Milan Province and the city of Milan, traditionally considered a no-risk zone, we have done some hypothesis of correlation between radon and the geochemical processes occurred in this area and soil permeability and fracturation by means of the existing geological sections. The application of the developed methodology will be useful to give advices to fill legislation gaps or to draft urban development plans.

  3. Estimation of the radon production rate in granite rocks and evaluation of the implications for geogenic radon potential maps: A case study in Central Portugal.

    Science.gov (United States)

    Pereira, A; Lamas, R; Miranda, M; Domingos, F; Neves, L; Ferreira, N; Costa, L

    2017-01-01

    The goal of this study was to estimate radon gas production rate in granitic rocks and identify the factors responsible for the observed variability. For this purpose, 180 samples were collected from pre-Hercynian and Hercynian rocks in north and central Portugal and analysed for a) (226)Ra activity, b) radon ((222)Rn) per unit mass activity, and c) radon gas emanation coefficient. On a subset of representative samples from the same rock types were also measured d) apparent porosity and e) apparent density. For each of these variables, the values ranged as follows: a) 15 to 587 Bq kg(-1), b) 2 to 73 Bq kg(-1), c) 0.01 to 0.80, d) 0.3 to 11.4 % and e) 2530 to 2850 kg m(-3). Radon production rate varied between 40 to 1386 Bq m(-3) h(-1). The variability observed was associated with geologically late processes of low and high temperature which led to the alteration of the granitic rock with mobilization of U and increase in radon (222)Rn gas emanation. It is suggested that, when developing geogenic radon potential maps, data on uranium concentration in soils/altered rock should be used, rather than data obtained from unaltered rock. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. A primary standard source of radon-222 based on the HPGe detector.

    Science.gov (United States)

    Mostafa, M Y A; Vasyanovich, M; Zhukovsky, M

    2017-02-01

    The present paper describes the prototype of a calibration standard system for radon concentrations to be used in establishing the traceability of radon concentration measurements in dwellings. Radon gas was generated with a radium-226 solid source in a certified volume as a closed system. The activity of the radon that was released in the closed system was determined from the difference between the absolute activity of the standard radium solid source and the residual radon decay products ((214)Bi or (214)Pb). A high-purity germanium (HPGe) detector, which was calibrated using gamma reference standard sources, was used to measure the activity of a radium solid source and radon decay products ((214)Bi or (214)Pb). The emanation factor of the (226)Ra source was controlled online with the HPGe detector. Radon activity was achieved at ~1500±45Bq from the radium source at 3.95±0.2kBq under equilibrium conditions. After this activity, the radon gas was transferred into the closed system producing radon activity concentrations of 31.1±0.3kBq/m(3). Systematic errors were found of less than 4% with a random error around 0.5%. The random error is generally associated with the estimation of the count rate of the measured radon progenies ((214)Po and (214)Po for alpha measurements or (214)Pb and (214)Bi for gamma measurements), but systematic errors are associated with the errors introduced by the instrumentation and measurement technique. The system that was developed has a high degree of accuracy and can be recommended as a national or regional prototype standard of radon activity concentration to calibrate different working radon measurement devices.

  5. Radon Guide for Tenants

    Science.gov (United States)

    This guide is for people who rent their apartments or houses. The guide explains what radon is, and how to find out if there is a radon problem in your home. The guide also talks about what you can do if there are high radon levels in your home.

  6. 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+.

  7. Multiple attenuation using λ-f domain high-resolution Radon transform

    Science.gov (United States)

    Li, Zhi-Na; Li, Zhen-Chun; Wang, Peng; Xu, Qiang

    2013-12-01

    The parabolic Radon transform has been widely used in multiple attenuation. To further improve the accuracy and efficiency of the Radon transform, we developed the λ-f domain high-resolution Radon transform based on the fast and modified parabolic Radon transform presented by Abbad. The introduction of a new variable λ makes the transform operator frequency-independent. Thus, we need to calculate the transform operator and its inverse operator only once, which greatly improves the computational efficiency. Besides, because the primaries and multiples are distributed on straight lines with different slopes in the λ-f domain, we can easily choose the filtering operator to suppress the multiples. At the same time, the proposed method offers the advantage of high-resolution Radon transform, which can greatly improve the precision of attenuating the multiples. Numerical experiments suggest that the multiples are well suppressed and the amplitude versus offset characteristics of the primaries are well maintained. Real data processing results further verify the effectiveness and feasibility of the method.

  8. Multiple attenuation usingλ-f domain high-resolution Radon transform

    Institute of Scientific and Technical Information of China (English)

    Li Zhi-Na; Li Zhen-Chun; Wang Peng; Xu Qiang

    2013-01-01

    The parabolic Radon transform has been widely used in multiple attenuation. To further improve the accuracy and efficiency of the Radon transform, we developed theλ-f domain high-resolution Radon transform based on the fast and modified parabolic Radon transform presented by Abbad. The introduction of a new variable λ makes the transform operator frequency-independent. Thus, we need to calculate the transform operator and its inverse operator only once, which greatly improves the computational efficiency. Besides, because the primaries and multiples are distributed on straight lines with different slopes in theλ-f domain, we can easily choose the filtering operator to suppress the multiples. At the same time, the proposed method offers the advantage of high-resolution Radon transform, which can greatly improve the precision of attenuating the multiples. Numerical experiments suggest that the multiples are well suppressed and the amplitude versus offset characteristics of the primaries are well maintained. Real data processing results further verify the effectiveness and feasibility of the method.

  9. Experimental study of effectiveness of four radon mitigation solutions, based on underground depressurization, tested in prototype housing built in a high radon area in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Frutos Vazquez, Borja, E-mail: borjafv@ietcc.csic.e [Eduardo Torroja Institute for Construction Science (a Spanish National Research Council body), C/Serreno Galvache 4, 28033 Madrid (Spain); Olaya Adan, Manuel [Eduardo Torroja Institute for Construction Science (a Spanish National Research Council body), C/Serreno Galvache 4, 28033 Madrid (Spain); Santiago Quindos Poncela, Luis; Sainz Fernandez, Carlos; Fuente Merino, Ismael [Medical Physics, Chair of the Faculty of Medicine, University of Cantabria, Cardenal Herrera Oria s/n, 39011 Santander (Spain)

    2011-04-15

    The present paper discusses the results of an empirical study of four approaches to reducing indoor radon concentrations based on depressurization techniques in underground sumps. The experiments were conducted in prototype housing built in an area of Spain where the average radon concentration at a depth of 1 m is 250 kBq m{sup -3}. Sump effectiveness was analysed in two locations: underneath the basement, which involved cutting openings into the foundation, ground storey and roof slabs, and outside the basement walls, which entailed digging a pit alongside the building exterior. The effectiveness of both sumps was likewise tested with passive and forced ventilation methods. The systems proved to be highly efficient, lowering radon levels by 91-99%, except in the solution involving passive ventilation and the outside sump, where radon levels were reduced by 53-55%. At wind speeds of over 8 m/s, however, passive ventilation across an outside sump lowered radon levels by 95% due to a Venturi effect induced drop in pressure. - Highlights: {yields} This experience can help to delimit effectiveness of this kind of depressurization solutions because all of them has been tested in the same radon exhalation rate conditions and in the same building. In this sense this paper constitute an original work and even more if we note that initial radon concentration were very high, in order of 40 kBq m{sup -3} in the basement {yields} Radon reduction up to 300 Bq m{sup -3} from 40 kBq m{sup -3} (initial conditions inside the building) {yields} The systems proved to be highly efficient, reducing radon levels by 91-99%, with the exception of the outside sump-natural convection combination, where rates declined on the order of 53-55% {yields} The effectiveness of the sump located outside the basement walls rose by 40 percentage points (from 53 to 93%) when forced rather than passive extraction was used. {yields} The natural convection extraction systems proved to be 40% more

  10. Effects of barium chlorine treatment of uranium ore on /sup 222/Rn emanation and /sup 226/Ra leachability from mill tailings

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, S.A.; Church, S.L.; Whicker, F.W.

    1985-01-01

    The purpose of this laboratory study was to investigate the effectiveness of barium chloride treatment of uranium ore on /sup 222/Rn emanation from mill tailings, /sup 226/Ra level in waste-water, and the leachability of radium from tailings. It has been shown that barium sulfate is an excellent carrier for radium and that barium sulfate crystals have high retention capacity for radon gas produced by radium trapped within the lattice. Ground uranium ore from a mine in Wyoming was mixed with water to form a 1:1 ratio before barium and potassium chlorides were added at concentrations of 0, 10, 25, 50, and 100 mg per liter of slurry. The ore was then subjected to a simulated mill process using sulfuric acid leaching. The liquid representing tailings pond water was separated and analyzed for /sup 226/Ra and the solid fraction, representing mill tailings, was tested for radon emanation and the leachability of radium by deionized water. This study suggests that barium treatment of uranium ore prior to sulfuric acid leaching could be effective in reducing radon emanation from tailings and also in reducing the /sup 226/Ra concentration of waste-water. Leachability of radium from treated tailings was markedly reduced.

  11. High concentrations of radon. Specifically affected buildings; Hohe Radonkonzentrationen. Besonders betroffene Gebaeudetypen

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Winfried [Bundesamt fuer Strahlenschutz, Berlin (Germany)

    2015-07-01

    The paper presents a concept for the prognosis of exceeding probabilities of thresholds of radon in dwellings in different building types. A transfer model for the interface subsoil - building was used as a basis. The partial datasets obtained by stratification of five relevant building characteristics can be de-scribed by a 3-parametric-lognormal distribution good in most times. The available data permit statistical predictions to 60 combinations of building characteristics for the region ''east'' and 85 combinations of building characteristics for the region ''West''. The uncertainties for the probability of exceeding a threshold were estimated from the data with bootstrapping. The importance of different building characteristics for the presence of enhanced radon concentrations can be predicted from the results of this estimation. Therefore, targeting of affected buildings is possible on this basis. Regional prognoses of exceeding probabilities for building types with high presence can also be created by the use of transfer factors. A Strategy to reduce the health risk from radon in the long run might be derived, where alongside the delineation of radon prone areas, special attention should be paid to a set out building characteristics, also outside the radon prone areas.

  12. Assessment of (222)Rn emanation from ore body and backfill tailings in low-grade underground uranium mine.

    Science.gov (United States)

    Mishra, Devi Prasad; Sahu, Patitapaban; Panigrahi, Durga Charan; Jha, Vivekanand; Patnaik, R Lokeswara

    2014-02-01

    This paper presents a comparative study of (222)Rn emanation from the ore and backfill tailings in an underground uranium mine located at Jaduguda, India. The effects of surface area, porosity, (226)Ra and moisture contents on (222)Rn emanation rate were examined. The study revealed that the bulk porosity of backfill tailings is more than two orders of magnitude than that of the ore. The geometric mean radon emanation rates from the ore body and backfill tailings were found to be 10.01 × 10(-3) and 1.03 Bq m(-2) s(-1), respectively. Significant positive linear correlations between (222)Rn emanation rate and the (226)Ra content of ore and tailings were observed. For normalised (226)Ra content, the (222)Rn emanation rate from tailings was found to be 283 times higher than the ore due to higher bulk porosity and surface area. The relative radon emanation from the tailings with moisture fraction of 0.14 was found to be 2.4 times higher than the oven-dried tailings. The study suggested that the mill tailings used as a backfill material significantly contributes to radon emanation as compared to the ore body itself and the (226)Ra content and bulk porosity are the dominant factors for radon emanation into the mine atmosphere.

  13. Radon screening for XENON1T

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, Sebastian [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    2015-07-01

    Radon with its isotope {sup 222}Rn is one of the dominant sources of internal background in liquid xenon detectors searching for low energetic rare events like WIMP-nucleon scattering. In my talk I briefly review the problem posed by {sup 222}Rn and motivate the screening strategy followed by XENON1T. I introduce the radon emanation technique making use of ultra low background proportional counters and present selected results obtained during the design and construction phases of XENON1T. Finally, I sketch advances in radon emanation assay techniques and give a short outlook on upcoming measurements.

  14. Radon-thoron discriminative measurements in the high natural radiation areas of southwestern Cameroon.

    Science.gov (United States)

    Saïdou; Tokonami, Shinji; Janik, Miroslaw; Samuel, Bineng Guillaume; Abdourahimi; Joseph Emmanuel, Ndjana Nkoulou I I

    2015-12-01

    Although indoor radon was initially measured in the uranium regions of Poli and Lolodorf using Electret Ionization Chambers, discriminative RADUET detectors were deployed in 70 houses of the high natural radiation areas of Bikoue and Ngombas in the uranium region of Lolodorf in Southwestern Cameroon. Radon and thoron concentrations were determined using Image-J and Microscope Methods for track evaluation. Radon and thoron concentrations follow lognormal distributions and ranged respectively from 27 ± 26 to 937 ± 5 Bq m(-3) and from 48 ± 40 to 700 ± 128 Bq m(-3). The arithmetic means of radon and thoron concentrations were found to be 92 ± 3 Bq m(-3) and 260 ± 13 Bq m(-3.) Less than 2% of houses have indoor radon above the reference level of 300 Bq m(-3) and 30% of houses have thoron concentrations above 300 Bq m(-3.) Inhalation doses due to radon and thoron range respectively between 0.6-17.7 mSv yr(-1) and 0.2-3 mSv yr(-1) with the mean values of 1.4 mSv yr(-1) and 1 mSv yr(-1). The contribution of indoor thoron to the total inhalation dose ranges between 15%- 78.5% with the mean value of 47%. Thus thoron cannot be neglected when assessing radiation dose.

  15. Novel method of measurement of radon exhalation from building materials.

    Science.gov (United States)

    Awhida, A; Ujić, P; Vukanac, I; Đurašević, M; Kandić, A; Čeliković, I; Lončar, B; Kolarž, P

    2016-11-01

    In the era of the energy saving policy (i.e. more air tight doors and windows), the radon exhaled from building materials tends to increase its concentration in indoor air, which increases the importance of the measurement of radon exhalation from building materials. This manuscript presents a novel method of the radon exhalation measurement using only a HPGe detector or any other gamma spectrometer. Comparing it with the already used methods of radon exhalation measurements, this method provides the measurement of the emanation coefficient, the radon diffusion length and the radon exhalation rate, all within the same measurement, which additionally defines material's radon protective properties. Furthermore it does not necessitate additional equipment for radon or radon exhalation measurement, which simplifies measurement technique, and thus potentially facilitates introduction of legal obligation for radon exhalation determination in building materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. The radon indicator

    Science.gov (United States)

    Samuelsson, L.

    2005-11-01

    The radon indicator is an efficient instrument for measuring the radon daughter concentrations in a house or dwelling. Physics or environmental science students could build a radon indicator as a student project. Another possibility would be to use a radon indicator in a student investigation of radon levels in different houses. Finally the radon indicator is an excellent device for producing a radioactive source, free of charge, for the study of α-, β- and γ-radiation. The half-life of the activity collected is approximately 40 min. The radon indicator makes use of an electrostatic method by which charged particles are drawn to a small aluminium plate with a high negative voltage (-5 kV), thus creating a strong electric field between the plate and a surrounding copper wire. The radioactivity on the plate is subsequently measured by a GM-counter and the result calculated in Bq m-3. The collecting time is just 5.5 min and therefore the instrument is only suitable for use in a short-time method for indicating the radon concentration. An improved diagram, ground-radon and/or wall-radon in houses, is presented on the basis of the author's measurements recorded with the radon indicator over many years. This diagram is very useful when discussing how to reduce radiation levels in homes.

  17. Radon and radioactivity at a town overlying Uranium ores in northern Greece.

    Science.gov (United States)

    Kourtidis, K; Georgoulias, A K; Vlahopoulou, M; Tsirliganis, N; Kastelis, N; Ouzounis, K; Kazakis, N

    2015-12-01

    Extensive measurements of (222)Rn in the town of Xanthi in N Greece show that the part of the town overlying granite deposits and the outcrop of a uranium ore has exceptionally high indoor radon levels, with monthly means up to 1500 Bq m(-3). A large number of houses (40%) in this part of the town exhibit radon levels above 200 Bq m(-3) while 11% of the houses had radon levels above 400 Bq m(-3). Substantial interannual variability as well as the highest in Europe winter/summer ratios (up to 12) were observed in this part of the town, which consist of traditional stone masonry buildings of the late 19th-early 20th century. Measurements of (238)U and (232)Th content of building materials from these houses as well as radionuclide measurements in different floors show that the high levels of indoor radon measured in these buildings are not due to high radon emanation rates from the building materials themselves but rather due to high radon flux from the soil because of the underlying geology, high radon penetration rates into the buildings from underground due to the lack of solid concrete foundations in these buildings, or a combination thereof. From the meteorological variables studied, highest correlation with indoor (222)Rn was found with temperature (r(2) = 0.65). An indoor radon prognostic regression model using temperature, pressure and precipitation as input was developed, that reproduced indoor radon with r(2) = 0.69. Hence, meteorology is the main driving factor of indoor radon, with temperature being the most important determinant. Preliminary flux measurements indicate that the soil-atmosphere (222)Rn flux should be in the range 150-250 Bq m(-2) h(-1), which is in the upper 10% of flux values for Europe.

  18. Radon as a tracer for soil-gas entry into a house located next to a contaminated dry-cleaning property; Radon som sporgas for jordluftindtraengning til hus ved forurenet renserigrund

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, C.E

    2001-07-01

    This study applies the naturally occurring radioactive gas radon-222 as a tracer for soil-gas entry into a house located next to a dry-cleaners shop. This is possible because the concentration of radon in the soil below the house is about 1000 times higher than the concentration in outdoor air. The study is based on continuous indoor measurement of radon, differential pressures, barometric pressure and temperatures and grab samples of radon below the slab and in the soil in the vicinity of the house. During the investigation, vacuum extraction were used to remove chlorinated solvents (perchloroethylene, PCE) from the unsaturated zone. The study shows that the vacuum extraction influences the radon concentration in and below the house. When the vacuum pump is on, the indoor radon concentration is only 10 Bq/m{sup 3} corresponding to the contribution from radon in outdoor air and exhalation from building materials. When the vacuum pump is set off, the average indoor radon concentration increases to 30 Bq/m{sup 3}. It is believed that the increase is caused by radon entry from the soil. Regression analysis demonstrates that changes in the indoor radon concentration can be explained by changes in indoor-outdoor pressure differences and changes in the atmospheric pressure. This suggests that advection is the primary mode of entry. Under some highly simplifying assumptions the soil-gas entry is found to be around 1 m{sup 3}/h. This, however, is most likely an overestimate. Based on the measured radon concentration in the exhaust air from the vacuum system and a typical radon emanation rate for Danish soil, it is estimated that the soil vapor extraction system ventilates about 10000 m{sup 3} of soil. The investigation is supported by numerical model calculations with the finite-volume model Rnmod3d. (au)

  19. Radon exhalation from Libyan soil samples measured with the SSNTD technique.

    Science.gov (United States)

    Saad, A F; Abdallah, R M; Hussein, N A

    2013-02-01

    Radon concentrations in soil samples collected from the cities of Benghazi and Al-Marj, located in northeastern Libya, were measured using the sealed-can technique based on the CR-39 SSNTDs. Mass and areal radon exhalation rates, radium content and radon concentration contribute to indoor radon, and annual effective doses were determined. The results indicate mostly normal rates, but there were some higher levels of radon concentration and emanation in samples collected from Al-Marj and one sample from Benghazi.

  20. Development of a predictive methodology for identifying high radon exhalation potential areas; Mise au point d'une methodologie predictive des zones a fort potentiel d'exhalation du radon

    Energy Technology Data Exchange (ETDEWEB)

    Ielsch, G

    2001-07-01

    Radon 222 is a radioactive natural gas originating from the decay of radium 226 which itself originates from the decay of uranium 23 8 naturally present in rocks and soil. Inhalation of radon gas and its decay products is a potential health risk for man. Radon can accumulate in confined environments such as buildings, and is responsible for one third of the total radiological exposure of the general public to radiation. The problem of how to manage this risk then arises. The main difficulty encountered is due to the large variability of exposure to radon across the country. A prediction needs to be made of areas with the highest density of buildings with high radon levels. Exposure to radon varies depending on the degree of confinement of the habitat, the lifestyle of the occupants and particularly emission of radon from the surface of the soil on which the building is built. The purpose of this thesis is to elaborate a methodology for determining areas presenting a high potential for radon exhalation at the surface of the soil. The methodology adopted is based on quantification of radon exhalation at the surface, starting from a precise characterization of the main local geological and pedological parameters that control the radon source and its transport to the ground/atmosphere interface. The methodology proposed is innovative in that it combines a cartographic analysis, parameters integrated into a Geographic Information system, and a simplified model for vertical transport of radon by diffusion through pores in the soil. This methodology has been validated on two typical areas, in different geological contexts, and gives forecasts that generally agree with field observations. This makes it possible to identify areas with a high exhalation potential within a range of a few square kilometers. (author)

  1. Radon in Soil Gas Above Bedrock Fracture Sets at the Shepley’s Hill Superfund Site

    Energy Technology Data Exchange (ETDEWEB)

    J.R. Giles; T.L. McLing; M.V. Carpenter; C.J. Smith; W. Brandon

    2012-12-01

    The Idaho National Laboratory (INL) recently provided technical support for ongoing environmental remediation activities at the Shepley’s Hill remediation site near Devens, MA (Figure 1). The technical support was requested as follow-on work to an initial screening level radiation survey conducted in 2008. The purpose of the original study was to assess the efficacy of the INL-developed Backpack Sodium Iodide System (BaSIS) for detecting elevated areas of natural radioactivity due to the decay of radon-222 gases emanating from the underlying fracture sets. Although the results from the initial study were mixed, the BaSIS radiation surveys did confirm that exposed bedrock outcrops have higher natural radioactivity than the surficial soils, thus a high potential for detecting elevated levels of radon and/or radon daughter products. (INL 2009) The short count times associated with the BaSIS measurements limited the ability of the system to respond to elevated levels of radioactivity from a subsurface source, in this instance radon gas emanating from fracture sets. Thus, it was postulated that a different methodology be employed to directly detect the radon in the soil gases. The CR-39 particle track detectors were investigated through an extensive literature and technology search. The relatively long deployment or “detection” time of several days, as well as the sensitivity of the measurement and robustness of the detectors made the CR-39 technology promising for deployment at the Shepley’s Hill site.

  2. RELATED GENES IN LUNG CANCER TISSUES ASSOCIATED WITH RESIDENTIAL HIGH RADON EXPOSURE

    Institute of Scientific and Technical Information of China (English)

    夏英; 杨梅英; 张守志; 叶常青

    2002-01-01

    Objective: To investigate the related genes in lung cancer tissues associated with residential high radon exposure. Methods: Differentially expressed gene fragments in lung cancer and normal lung tissues were discovered by differential display and reverse Northern blot hybridization method. The fragments positive in lung cancer and negative in normal lung tissue were determined. Results: Seven differential displayed fragments were sequenced. One of them named NA7 is 95% homologous with AI208667 in EAT of Genbank. Another fragment named NG2 is up to 98% homologous with five fragments. The remained one CA1 may be a new gene fragment. Conclusion: 3 gene fragments were discovered from lung cancer and normal lung tissues of high radon exposure resident.

  3. Survey of Gamma Dose and Radon Exhalation Rate from Soil Surface of High Background Natural Radiation Areas in Ramsar, Iran

    Directory of Open Access Journals (Sweden)

    Rouhollah Dehghani

    2013-09-01

    Full Text Available Background: Radon is a radioactive gas and the second leading cause of death due to lung cancer after smoking. Ramsar is known for having the highest levels of natural background radiation on earth. Materials and Methods: In this research study, 50 stations of high radioactivity areas of Ramsar were selected in warm season of the year. Then gamma dose and radon exhalation rate were measured.Results: Results showed that gamma dose and radon exhalation rate were in the range of 51-7100 nSv/hr and 9-15370 mBq/m2s, respectively.Conclusion: Compare to the worldwide average 16 mBq/m2s, estimated average annual effective of Radon exhalation rate in the study area is too high.

  4. Development of a technique for the measurement of the radon exhalation rate using an activated charcoal collector

    Energy Technology Data Exchange (ETDEWEB)

    Iimoto, Takeshi [Graduate School of Engineering, University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)], E-mail: iimoto@n.t.u-tokyo.ac.jp; Akasaka, Yoshinori [Graduate School of Engineering, University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Koike, Yuya [Radioisotope Center, University of Tokyo (Japan); Kosako, Toshiso [Graduate School of Engineering, University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)

    2008-04-15

    A simple system to evaluate the {sup 222}Rn (radon) exhalation rate from soil has been improved. A sampling cuvette of 2.1 L is placed so that it covers the targeted ground soil, and radon emanating from the soil accumulates within the cuvette for 24 h. Its internal radon concentration is measured by the combination of an activated charcoal (PICO-RAD) and a liquid scintillation counting system. This study shows variations of the conversion factor (CF: unit Bq m{sup -3}/cpm) of PICO-RAD. The range of CF due to temperature (10-30 deg. C) was between -21% and +69%, and this due to humidity (30-90%) was between 0% and -15%. Humidity and radon concentration in the cuvette covering soil tended to saturate in a few hours. The above information was used to correct the CF for the evaluation. The improved system shows high reliability and can be easily applied to natural environments.

  5. Development of a technique for the measurement of the radon exhalation rate using an activated charcoal collector.

    Science.gov (United States)

    Iimoto, Takeshi; Akasaka, Yoshinori; Koike, Yuya; Kosako, Toshiso

    2008-04-01

    A simple system to evaluate the 222Rn (radon) exhalation rate from soil has been improved. A sampling cuvette of 2.1 L is placed so that it covers the targeted ground soil, and radon emanating from the soil accumulates within the cuvette for 24 h. Its internal radon concentration is measured by the combination of an activated charcoal (PICO-RAD) and a liquid scintillation counting system. This study shows variations of the conversion factor (CF: unit Bq m(-3)/cpm) of PICO-RAD. The range of CF due to temperature (10-30 degrees C) was between -21% and +69%, and this due to humidity (30-90%) was between 0% and -15%. Humidity and radon concentration in the cuvette covering soil tended to saturate in a few hours. The above information was used to correct the CF for the evaluation. The improved system shows high reliability and can be easily applied to natural environments.

  6. Indoor radon; Le radon dans les batiments

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    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.

  7. Variation of radon-222 concentration in exposure systems air under different conditions of exposure

    Science.gov (United States)

    Mamoon, A.; Abdul-Fattah, A. A.; Qari, T. M.

    1994-07-01

    Simplified, laboratory scale systems, namely ordinary laboratory desiccators and cylindrical containers were tested with regard to their reliability as exposure systems for determining certain parameters of radon emanation from locally obtained crushed granite rock samples. The samples were placed inside the exposure systems. Activity concentration of emanated radon in the exposure systems air increased with increase of mass of granite sample in the desiccator and with length of the exposure period. Activity concentration of radon was high near the granitic source but decreased with vertical distance from it when the exposure system was semiclosed but activity was homogeneous when the system was completely closed. The cylindrical exposure system was used in assessing Ra-226 content in some crushed granitic samples identified as altered alkali granite and found to be: 0.024 Bq g-1 (0.65 pCig-1). Rn-222 emanation rate from the same samples was: 0.013 Bq m-2 s-1 (0.34 pCi m-2 s-1). Saturation density thickness for a mixed sample of pure and alkali granites was found to be 116 g cm-2. The results agree in general with reported observations and support the reliability of the exposure systems used.

  8. Factors influencing upstairs and downstairs radon levels in two-storey dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Denman, A.R.; Groves-Kirkby, C.J.; Groves-Kirkby, N.P. [Northampton General Hospital, Medical Physics Dept. (United Kingdom); Crockett, R.G.M.; Phillips, P.S.; Woolridge, A.C. [Northampton Univ., School of Applied Sciences (United Kingdom); Woolridge, A.C. [Northampton Univ., School of Health (United Kingdom)

    2006-07-01

    Environmental radon exposure of residents of two-storey domestic premises is generally estimated on the basis of the measured radon concentrations in, and the relative occupancies of, the principal living-room and bed-room, assuming 45% and 55% occupancy of these two locations respectively. In practice, however, significant case-to-case variability exists, both in the relative periods that individuals spend in the upstairs and downstairs rooms of storey homes, and in the relative radon levels in these two areas. Moreover, while it is assumed that radon levels in upper storeys of multi-storey homes will be intrinsically lower than at ground level, this is not always the case, since radon exhalation from the materials from which the house is constructed may contribute significantly to indoor levels. While studies on radon level variability in the individual units in apartment blocks have been reported, the situation in two-storey low-rise dwellings appears not to have been considered. To investigate this, detailed extended measurements of radon concentrations were made in a set of thirty-four homes situated in areas of Northamptonshire known to exhibit high radon levels and declared a radon Affected Area by the United Kingdom (UK) National Radiological Protection Board (NRPB) in 1992. All homes were of typical UK construction of brick/block/stone walls under a pitched tile/slate roof. Approximately 50% of the sample were detached houses, the remainder being semidetached (duplex) or terraced (row-house). Around 25% of the sample possessed cellars, while 12% were single-storey dwellings. In two-storey homes, all monitored bedrooms were on the upper floor. Distribution of the ratios of bedroom/living-room radon levels in individual properties was left-skewed (mean 0.67, median 0.73, range 0.05 to 1.05). The mean is consistent with the outcome of early NRPB studies in England, while the variability depends principally on the characteristics of the property, and not on

  9. Measuring radon-222 in soil gas with high spatial and temporal resolution.

    Science.gov (United States)

    Huxtable, Darren; Read, David; Shaw, George

    2017-02-01

    In order to exploit (222)Rn as a naturally-occurring tracer in soils we need to sample and measure radon isotopes in soil gas with high spatial and temporal resolution, without disturbing in situ activity concentrations and fluxes. Minimisation of sample volume is key to improving the resolution with which soil gas can be sampled; an analytical method is then needed which can measure radon with appropriate detection limits and precision for soil gas tracer studies. We have designed a soil gas probe with minimal internal dead volume to allow us to sample soil gas volumes of 45 cm(3). Radon-222 is extracted from these samples into a mineral oil-based scintillation cocktail before counting on a conventional liquid scintillation counter. A detection limit of 320 Bq m(-3) (in soil gas) is achievable with a 1 h count. This could be further reduced but, in practice, is sufficient for our purpose since (222)Rn in soil gas typically ranges from 2000-50,000 Bq m(-3). The method is simple and provides several advantages over commonly used field-portable instruments, including smaller sample volumes, speed of deployment and reliability under field conditions. The major limitation is the need to count samples in a liquid scintillation counter within 2-3 days of collection, due to the short (3.824 day) radioactive half-life of (222)Rn. The method is not applicable to the very short-lived (55 s half-life) (220)Rn.

  10. World History Of Radon Research And Measurement From The Early 1900's To Today

    Science.gov (United States)

    George, A. C.

    2008-08-01

    In 1900, Dorn discovered the emanation in the uranium series that eventually became the well-known gas 222Rn. From 1900 through 1908, it was demonstrated that 222Rn is a radioactive gas found in tap water, highly condensable at low temperatures with a half-life of approximately 3.7 days and can be collected on charcoal by adsorption. Although, radon was discovered in 1900, the effects of prolonged exposure had been suspected and noted 300 years earlier among underground miners who developed lung cancer. During the period from 1924-1932, it was suggested that radon was the cause of high lung cancer incidence. In 1951, researchers at the university of Rochester N.Y. pointed out that the lung cancer health hazard was from the alpha radiation dose delivered by the radon decay products that deposited in the respiratory tract. The findings of the BEIR Committee Report VI, which was based on epidemiological studies in different groups of mines in the 1950's and 1960's and on laboratory studies, showed that from 60,000 miners over 2,600 developed lung cancer where only 750 were expected. Since 1998, the epidemiological study conducted in Iowa US, showed beyond any reasonable doubt that radon decay products cause lung cancer among women who lived at least twenty years in their homes. This paper will cover early radon measurements in soil, building material, ground water and in different air environments such as in the atmosphere, caves spas, underground mines and in residential indoor air environment. Radon measurements were conducted in many areas for diagnostic purposes. Radon was used as natural tracer to study air masses, vertical diffusion, and atmospheric studies, in earthquake prediction, and as a geological indicator for radium and uranium. In the early radon measurements, electroscopes, electrometers and primitive ionization chambers were used for many years. In the 1940's fast pulse ionization chambers replaced total ionization chambers. From the mid 1950's

  11. Is radon a potential risk in geothermal fields?

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar, M.; Tavera, L.; Lopez, A. [Instituto Nacional de Investigaciones Nucleares, Mexico City (Mexico)

    1998-12-31

    Some environmental groups in Mexico have shown concern, by the fact that natural radon emanation in geothermal fields could be considered as a potential risk for human health. As part of the studies recommended by the Ministry of Energy and to provide technical answers to the request of environmental groups, a study of the radon emanation and its impact to human health was carried out at the Primavera Mexican geothermal energy field under prospecting. It was found that radon concentration decreases with temperature of geothermal fluids and increases with the enthalpy of the well. In any case, using the appropriate corrections, radon values were similar to those of ground water. Radon values in the atmosphere of the field show no potential risk for human health. (author)

  12. Radon release from granites in south-west England

    CERN Document Server

    Poole, J

    2001-01-01

    accessory minerals. The enhancement of surface area was attributed to the alteration of feldspar to sericite. This has implications for the release of radon. It is thought that the large surface area provides a sink for the adsorption of radon, retaining it in the rock structure. This radon retention explains the paradoxical decline in radon release at small particle size/large specific surface area. Various mechanisms for radon emanation are discussed with reference to the Cornubian granites. It is shown that, based on the measured specific surface areas, inter-crystalline diffusion is a slow process and not a significant contributor to overall radon release (0.01%). Approximately 1% of the total radon produced can be attributed to direct recoil processes, based on the calculated recoil ranges (36 nm). The remainder was attributed to diffusion processes through crystal imperfections and dislocations. The microscopic scale model developed here is extended to the macroscopic scale through examination of the la...

  13. Radon as an Anthropogenic Indoor Air Pollutant

    Science.gov (United States)

    Gillmore, Gavin; Crockett, Robin

    2016-04-01

    Radon is generally regarded as a naturally occurring radiological hazard but we report here measurements of significant, hazardous radon concentrations that arise from man-made sources, including granite ornaments/artefacts, uranium glass and glazed objects as well radium dial watches. This presentation concerns an examination and assessment of health risks from radium and uranium found in historical artefacts, many of which were once viewed as everyday items, and the radon that emanates from them. Such objects were very popular in industrialised countries such as the USA, UK and European countries) particularly between and including the two World Wars but are still readily available. A watch collection examined gave rise to a hazardous radon concentration of 13.24 kBq•m-3 approximately 67 times the Domestic Action Level of 200 Bq•m-3.The results for an aircraft altimeter are comparable to those of the watches, indicating radon activity equivalent to several watches, and also indicate an equilibrium concentration in the 16.3 m3 room ca. 33 times the UK domestic Action Level. Results from a granite block indicate a radon emanation of 19.7 Bq•kg-1, but the indicated equilibrium concentration in the 16.3 m3 room is only ca. 1.7% of the UK domestic Action Level. Uranium-glazed crockery and green uranium glass were scoped for radon activity. The former yielded a radon concentration of ca. 44 Bq•m-3 in a small (7 L) sealed container. The latter yielded a lower radon concentration in a larger (125 L) sealed container of ca. 6 Bq•m-3. This is barely above the background radon concentration in the laboratory, which was typically ca. 1-2 Bq•m-3. Individual items then are capable of giving rise to radon concentrations in excess of the UK Domestic Action Level in rooms in houses, particularly if poorly ventilated. We highlight the gap in the remediation protocols, which are focused on preventing radon entering buildings from outside, with regard to internally

  14. Environmental radon studies in Mexico.

    Science.gov (United States)

    Segovia, N; Gaso, M I; Armienta, M A

    2007-04-01

    Radon has been determined in soil, groundwater, and air in Mexico, both indoors and outdoors, as part of geophysical studies and to estimate effective doses as a result of radon exposure. Detection of radon has mainly been performed with solid-state nuclear track detectors (SSNTD) and, occasionally, with active detection devices based on silicon detectors or ionization chambers. The liquid scintillation technique, also, has been used for determination of radon in groundwater. The adjusted geometric mean indoor radon concentration (74 Bq m-3) in urban developments, for example Mexico City, is higher than the worldwide median concentration of radon in dwellings. In some regions, particularly hilly regions of Mexico where air pollution is high, radon concentrations are higher than action levels and the effective dose for the general population has increased. Higher soil radon levels have been found in the uranium mining areas in the northern part of the country. Groundwater radon levels are, in general, low. Soil-air radon contributing to indoor atmospheres and air pollution is the main source of increased exposure of the population.

  15. Radon exhalation rates from some soil samples of Kharar, Punjab

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, Vimal [Deptt of Physics, M. M. University, Mullana (Ambala)-133 207 (India); Deptt of Physics, Punjabi University, Patiala- 147 001 (India); Singh, Tejinder Pal, E-mail: tejinders03@gmail.com [Deptt of Physics, S.A. Jain (P.G.) College, Ambala City- 134 003 (India); Chauhan, R. P. [Deptt of Physics, National Institute of Technology, Kurukshetra- 136 119 (India); Mudahar, G. S. [Deptt of Physics, Punjabi University, Patiala- 147 001 (India)

    2015-08-28

    Radon and its progeny are major contributors in the radiation dose received by general population of the world. Because radon is a noble gas, a large portion of it is free to migrate away from radium. The primary sources of radon in the houses are soils and rocks source emanations, emanation from building materials, and entry of radon into a structure from outdoor air. Keeping this in mind the study of radon exhalation rate from some soil samples of the Kharar, Punjab has been carried out using Can Technique. The equilibrium radon concentration in various soil samples of Kharar area of district Mohali varied from 12.7 Bqm{sup −3} to 82.9 Bqm{sup −3} with an average of 37.5 ± 27.0 Bqm{sup −3}. The radon mass exhalation rates from the soil samples varied from 0.45 to 2.9 mBq/kg/h with an average of 1.4 ± 0.9 mBq/kg/h and radon surface exhalation rates varied from 10.4 to 67.2 mBq/m{sup 2}/h with an average of 30.6 ± 21.8 mBq/m{sup 2}/h. The radon mass and surface exhalation rates of the soil samples of Kharar, Punjab were lower than that of the world wide average.

  16. Radon content in Danish till deposits: relationship with redox conditions and age

    Energy Technology Data Exchange (ETDEWEB)

    Gravesen, P.; Roll Jakobsen, P.

    2010-07-15

    This paper presents some results concerning the radon content and emanation rates in different Danish till deposits of Saalian and Weichselian age from a study carried out by the Geological Survey of Denmark and Greenland (GEUS). (LN)

  17. Legal issues in radon affairs

    Energy Technology Data Exchange (ETDEWEB)

    Massuelle, M.H. [Inst. de Protection et de Surete Nucleaire, Fontenay aux Roses (France)

    1999-12-01

    In France, it was only recently that cases related to high radon concentrations in dwellings received substantial publicity. This irruption of radon as a public health issue came with the general progress of scientific knowledge and the availability of a research capacity in France able to develop expertise. We are interested here in the legal implications of issues that arise from the lag between the activity of expertsand the regulatory activity in the domain of radon. We use the term expertise very broadly, to cover the practical application of research findings, the relation of the researchers with the community, and finally the acts by which experts provide their knowledge to the community. We first examine the course by which science developed the radon issue and the way they organized to move from research to expertise; here we try to characterize the various needs for radon expertise. We then discuss the legal difficulties associated with radon expertise.

  18. Radon mapping strategies in Austria.

    Science.gov (United States)

    Gruber, V; Ringer, W; Wurm, G; Friedmann, H

    2015-11-01

    According to current European and international recommendations (e.g. by IAEA, WHO and European Union), countries shall identify high radon areas. In Austria, this task was initiated already in the early 1990s, which yielded the first Austrian Radon Potential Map. This map is still in use, updated with recent indoor radon data in 2012. The map is based on radon gas measurements in randomly selected dwellings, normalised to a standard situation. To meet the current (legal) requirements, uncertainties in the existing Austrian radon map should be reduced. A new indoor radon survey with a different sampling strategy was started, and possible mapping methods are studied and tested. In this paper, the methodology for the existing map as well as the planned strategies to improve this map is discussed.

  19. Legal issues in radon affairs

    Energy Technology Data Exchange (ETDEWEB)

    Massuelle, M.H. [Inst. de Protection et de Surete Nucleaire, Fontenay aux Roses (France)

    1999-12-01

    In France, it was only recently that cases related to high radon concentrations in dwellings received substantial publicity. This irruption of radon as a public health issue came with the general progress of scientific knowledge and the availability of a research capacity in France able to develop expertise. We are interested here in the legal implications of issues that arise from the lag between the activity of expertsand the regulatory activity in the domain of radon. We use the term expertise very broadly, to cover the practical application of research findings, the relation of the researchers with the community, and finally the acts by which experts provide their knowledge to the community. We first examine the course by which science developed the radon issue and the way they organized to move from research to expertise; here we try to characterize the various needs for radon expertise. We then discuss the legal difficulties associated with radon expertise.

  20. 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 inho

  1. 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 inho

  2. Correlation analysis of the natural radionuclides in soil and indoor radon in Vojvodina, Province of Serbia.

    Science.gov (United States)

    Forkapic, S; Maletić, D; Vasin, J; Bikit, K; Mrdja, D; Bikit, I; Udovičić, V; Banjanac, R

    2017-01-01

    The most dominant source of indoor radon is the underlying soil, so the enhanced levels of radon are usually expected in mountain regions and geology units with high radium and uranium content in surface soils. Laboratory for radioactivity and dose measurement, Faculty of Sciences, University of Novi Sad has rich databases of natural radionuclides concentrations in Vojvodina soil and also of indoor radon concentrations for the region of Vojvodina, Northern Province of Serbia. In this paper we present the results of correlative and multivariate analysis of these results and soil characteristics in order to estimate the geogenic radon potential. The correlative and multivariate analysis were done using Toolkit for Multivariate Analysis software package TMVA package, within ROOT analysis framework, which uses several comparable multivariate methods for our analysis. The evaluation ranking results based on the best signal efficiency and purity, show that the Boosted Decision Trees (BDT) and Multi Layer Preceptor (MLP), based on Artificial Neural Network (ANN), are multivariate methods which give the best results in the analysis. The BDTG multivariate method shows that variables with the highest importance are radio-nuclides activity on 30 cm depth. Moreover, the multivariate regression methods give a good approximation of indoor radon activity using full set of input variables. On several locations in the city of Novi Sad the results of indoor radon concentrations, radon emanation from soil, gamma spectrometry measurements of underlying soil and geology characteristics of soil were analyzed in detail in order to verify previously obtained correlations for Vojvodina soil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. ERRICCA radon model intercomparison exercise

    DEFF Research Database (Denmark)

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

    1999-01-01

    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 morefundamental studies of radon transport. To ascertain ......, 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....

  4. High annual radon concentration in dwellings and natural radioactivity content in nearby soil in some rural areas of Kosovo and Metohija

    Directory of Open Access Journals (Sweden)

    Gulan Ljiljana R.

    2013-01-01

    Full Text Available Some previous studies on radon concentration in dwellings of some areas of Kosovo and Metohija have revealed a high average radon concentration, even though the detectors were exposed for three months only. In order to better design a larger study in this region, the annual measurements in 25 houses were carried out as a pilot study. For each house, CR-39-based passive devices were exposed in two rooms for the two consecutive six-month periods to account for seasonal variations of radon concentration. Furthermore, in order to correlate the indoor radon with radium in nearby soil and to improve the knowledge of the natural radioactivity in the region, soil samples near each house were collected and 226Ra, 232Th, 40K activity concentration were measured. The indoor radon concentration resulted quite high from the average (163 Bq/m3 and generally it did not differ considerably between the two rooms and the two six-month periods. The natural radionuclides in soil resulted to be distributed quite uniformly. Moreover, the correlation between the226Ra content in soil and radon concentration in dwellings resulted to be low (R2=0.26. The annual effective dose from radon and its short-lived progeny (5.5 mSv, in average was calculated by using the last ICRP dose conversion factors. In comparison, the contribution to the annual effective dose of outdoor gamma exposure from natural radionuclides in soil is nearly negligible (66 mSv. In conclusion, the observed high radon levels are only partially correlated with radium in soil; moreover, a good estimate of the annual average of radon concentration can be obtained from a six-month measurement with a proper choice of exposure period, which could be useful when designing large surveys.

  5. Association of School District Policies for Radon Testing and Radon-Resistant New Construction Practices with Indoor Radon Zones.

    Science.gov (United States)

    Foster, Stephanie; Everett Jones, Sherry

    2016-12-13

    Radon is a naturally occurring, colorless, odorless, and tasteless radioactive gas. Without testing, its presence is unknown. Using nationally representative data from the 2012 School Health Policies and Practices Study, we examined whether the prevalence of school district policies for radon testing and for radon-resistant new construction practices varied by district location in relation to the U.S. Environmental Protection Agency Map of Radon Zones. Among school districts located in counties with high predicted average indoor radon, 42.4% had policies for radon testing and 37.5% had policies for radon-resistant new construction practices. These findings suggest a critical need for improved awareness among policy makers regarding potential radon exposure for both students and school staff.

  6. Radon migration in the soils of the Irno Valley (Southern Italy inferred from radioactive disequilibrium

    Directory of Open Access Journals (Sweden)

    P. Gasparini

    1995-06-01

    Full Text Available Radon migration along vertical profiles in the soils of Irno River alluvial Valley (Southern Italy was studied using radioactive disequilibrium between 226 Ra and 210 Pb. Fractional Radon loss, migration length, diffusion and emanation coefficient and Radon flux density were determined. Our results are in agreement with a migra- tion model by simple diffusion. The migration parameters are within typical values, except the Radon flux density, which is about one order of magnitude higher than the values reported in literature. The values of fractional Radon loss are sensitive to changes in the physical properties of the soil.

  7. A Novel Low Background Cryogenic Detector for Radon in Gas

    Science.gov (United States)

    Wójcik, Marcin; Zuzel, Grzegorz

    2007-03-01

    A prototype of a new detector for measurements of radon in gases and radon emanation investigations is presented. It is based on the low-temperature collection of 222Rn on a stainless steel plate and the following counting of emitted alpha particles using a standard ORTEC semiconductor detector for alpha spectroscopy. A low background of the constructed system was achieved, in the order of 25 counts per day for the 222Rn energy window. Relatively high detection efficiency of 32 % in 2π geometry, and large volume of the detector allow radon concentration measurements at the level of 12 mBq/m3 with a 30 % accuracy. The detector can be also used to measure short-lived 220Rn. In the next step we plan to improve the system so that we could reach the sensitivity of 1 mBq/m3. This can be achieved by reducing the background, improving the detection efficiency and/or increasing the active volume of the detector (with respect to the prototype).

  8. Low air exchange rate causes high indoor radon concentration in energy-efficient buildings.

    Science.gov (United States)

    Vasilyev, A V; Yarmoshenko, I V; Zhukovsky, M V

    2015-06-01

    Since 1995, requirements on energy-efficient building construction were established in Russian Building Codes. In the course of time, utilisation of such technologies became prevailing, especially in multi-storey building construction. According to the results of radon survey in buildings constructed meeting new requirements on energy efficiency, radon concentration exceeds the average level in early-constructed buildings. Preponderance of the diffusion mechanism of radon entry in modern multi-storey buildings has been experimentally established. The experimental technique of the assessment of ventilation rate in dwellings under real conditions was developed. Based on estimates of average ventilation rate, it was approved that measures to increase energy efficiency lead to reduction in ventilation rate and accumulation of higher radon concentrations indoors. Obtained ventilation rate values have to be considered as extremely low.

  9. Radon monitoring of microseismicity in the Kangra and Chambra valleys of Himachal Pradesh, India

    Energy Technology Data Exchange (ETDEWEB)

    Virk, H.S. [Guru Nanak Dev Univ., Amritsar (India). Dept. of Physics

    1995-04-01

    Data on radon emanation collected in soil-gas and groundwater at Palampur in the Kangra valley and Dalhausie in the Chamba valley of Himachal Pradesh is reported. Radon anomalies exhibit correspondence with some of the seismic events that occurred in the region along the Himalayan thrust faults. The study has proven the usefulness of radon as a precursor micro-seismic activity along the major faults. (author).

  10. A statistical evaluation of the influence of housing characteristics and geogenic radon potential on indoor radon concentrations in France.

    Science.gov (United States)

    Demoury, C; Ielsch, G; Hemon, D; Laurent, O; Laurier, D; Clavel, J; Guillevic, J

    2013-12-01

    Radon-222 is a radioactive natural gas produced by the decay of radium-226, known to be the main contributor to natural background radiation exposure. Effective risk management needs to determine the areas in which the density of buildings with high radon levels is likely to be highest. Predicting radon exposure from the location and characteristics of a dwelling could also contribute to epidemiological studies. Beginning in the nineteen-eighties, a national radon survey consisting in more than 10,000 measurements of indoor radon concentrations was conducted in French dwellings by the Institute for Radiological Protection and Nuclear Safety (IRSN). Housing characteristics, which may influence radon accumulation in dwellings, were also collected. More recently, the IRSN generated a French geogenic radon potential map based on the interpretation of geological features. The present study analyzed the two datasets to investigate the factors influencing indoor radon concentrations using statistical modeling and to determine the optimum use of the information on geogenic radon potential that showed the best statistical association with indoor radon concentration. The results showed that the variables associated with indoor radon concentrations were geogenic radon potential, building material, year of construction, foundation type, building type and floor level. The model, which included the surrounding geogenic radon potential (i.e. the average geogenic radon potential within a disc of radius 20 km centered on the indoor radon measurement point) and variables describing house-specific factors and lifestyle explained about 20% of the overall variability of the logarithm of radon concentration. The surrounding geogenic radon potential was fairly closely associated with the local average indoor radon concentration. The prevalence of exposure to radon above specific thresholds and the average exposures to radon clearly increased with increasing classes of geogenic radon

  11. Investigation of some factors affecting on release of radon-222 from phosphogypsum waste associated with phosphate ore processing.

    Science.gov (United States)

    Hilal, M A; El Afifi, E M; Nayl, A A

    2015-07-01

    The aim of this study is oriented to investigate the influence of some physicochemical factors such as radium distribution, grain size, moisture content and chemical constituents on releases of radon-222 from the accumulated phosphogypsum (PG) waste. The emanation fraction, activity concentration in the pore and the surface exhalation rate of radon-222 in the bulk PG waste are 34.5 ± 0.3%, 238.6 ± 7.8 kBq m(-3) and 213 ± 6.9 mBq m(-2) s(-1), respectively. These values were varied and enhanced slightly in the fine grain sizes (F1 radon from residue PG waste was controlled positively by radium (Ra-226), calcium (CaSO4) and strontium (SrO). About 67% of radon release attributed to the grain size below 0.5 mm, while 33% due to the large grain size above 0.5 mm. The emanation fraction of Rn-222 is increased with moisture content and the maximum emanation is ∼43% of moisture of 3-8%. It reduced slowly with the continuous increase in moisture till 20%. Due to PG waste in situ can be enhancing the background to the surround workers and/or public. Therefore, the environmental negative impacts due to release of Rn-222 can be minimized by legislation to restrict its civil uses, or increasing its moisture to ∼10%, or by the particle size separation of the fine fraction containing the high levels of Ra-226 followed by a suitable chemical treatment or disposal; whereas the low release amount can be diluted and used in cement industry, roads or dam construction.

  12. Pumping time required to obtain tube well water samples with aquifer characteristic radon concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Ricardo, Carla Pereira; Oliveira, Arno Heeren de, E-mail: heeren@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Escola de Engenharia. Dept. de Engenharia Nuclear; Rocha, Zildete; Palmieri, Helena E.L.; Linhares, Maria G.M.; Menezes, Maria Angela B.C., E-mail: rochaz@cdtn.br, E-mail: help@cdtn.br, E-mail: mgml@cdtn.br, E-mail: menezes@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Radon is an inert noble gas, which comes from the natural radioactive decay of uranium and thorium in soil, rock and water. Radon isotopes emanated from radium-bearing grains of a rock or soil are released into the pore space. Radon that reaches the pore space is partitioned between the gaseous and aqueous phases. Thus, the groundwater presents a radon signature from the rock that is characteristic of the aquifer. The characteristic radon concentration of an aquifer, which is mainly related to the emanation, is also influenced by the degree of subsurface degassing, especially in the vicinity of a tube well, where the radon concentration is strongly reduced. Looking for the required pumping time to take a tube well water sample that presents the characteristic radon concentration of the aquifer, an experiment was conducted in an 80 m deep tube well. In this experiment, after twenty-four hours without extraction, water samples were collected periodically, about ten minutes intervals, during two hours of pumping time. The radon concentrations of the samples were determined by using the RAD7 Electronic Radon Detector from Durridge Company, a solid state alpha spectrometric detector. It was realized that the necessary time to reach the maximum radon concentration, that means the characteristic radon concentration of the aquifer, is about sixty minutes. (author)

  13. Theoretical modeling of indoor radon concentration and its validation through measurements in South-East Haryana, India.

    Science.gov (United States)

    Singh, Prabhjot; Sahoo, B K; Bajwa, B S

    2016-04-15

    A three dimensional semi-empirical model deduced from the existing 1-D model has been used to predict indoor radon concentration with theoretical calculations. Since the major contributor of radon concentration in indoors originates from building materials used in construction of walls and floor which are mostly derived from soil. In this study different building materials have been analyzed for radon exhalation, diffusion length along with physical dimensions of observation area to calculate indoor radon concentration. Also calculated values have been validated by comparing with experimental measurements. The study has been carried out in the mud, brick and cement houses constructed from materials available locally in South-East region of Haryana. This region is also known for its protruding land structure consisting volcanic, felsite and granitic rocks in plane. Further, exhalation (Jw) ratio from wall and floor comparison has been plotted for each selected village dwelling to identify the high radon emanating source (building material) from the study region. All those measured factors might be useful in building construction code development and selection of material to be used in construction.

  14. Indoor radon (Rn-222) concentration measurements in Cyprus using high-sensitivity portable detectors

    CERN Document Server

    Anastasiou, T; Christofides, S; Christodoulides, G

    2003-01-01

    Using high--sensitivity radon (Rn-222) portable detectors, the airborne Rn-222 concentration in the interior of various Cypriot buildings and dwellings was measured. For each preselected building and dwelling, a calibrated detector was put into a closed room, and the Rn-222 concentration was registered in sampling intervals of 2 to 4 hours for a total counting time of typically 48 hours. Rn-222 activity concentrations were found to be in the range of 6.2 to 102.8 Bq/m**3, with an overall arithmetic mean value of (19.3 +- 1.6) Bq/m**3. This value is by a factor of two below the world average (population-weighted) value of 39 Bq/m**3. The total annual effective dose equivalent to the Cypriot population was calculated to be between 0.16 and 2.6 mSv with an overall arithmetic mean value of (0.49 +- 0.04) mSv.

  15. Rayleigh-wave mode separation by high-resolution linear radon transform

    Science.gov (United States)

    Luo, Y.; Xia, J.; Miller, R.D.; Xu, Y.; Liu, J.; Liu, Q.

    2009-01-01

    Multichannel analysis of surface waves (MASW) method is an effective tool for obtaining vertical shear wave profiles from a single non-invasive measurement. One key step of the MASW method is generation of a dispersion image and extraction of a reliable dispersion curve from raw multichannel shot records. Because different Rayleigh-wave modes normally interfere with each other in the time and space domain, it is necessary to perform mode separation and reconstruction to increase the accuracy of phase velocities determined from a dispersion image. In this paper, we demonstrate the effectiveness of high-resolution linear Radon transform (LRT) as a means of separating and reconstructing multimode, dispersive Rayleigh-wave energy. We first introduce high-resolution LRT methods and Rayleigh-wave mode separation using high-resolution LRT. Next, we use synthetic data and a real-world example to demonstrate the effectiveness of Rayleigh-wave mode separation using high-resolution LRT. Our synthetic and real-world results demonstrate that (1) high-resolution LRT successfully separates and reconstructs multimode dispersive Rayleigh-wave energy with high resolution allowing the multimode energy to be more accurately determined. The horizontal resolution of the Rayleigh-wave method can be increased by extraction of dispersion curves from a pair of traces in the mode-separated shot gather and (2) multimode separation and reconstruction expand the usable frequency range of higher mode dispersive energy, which increases the depth of investigation and provides a means for accurately determining cut-off frequencies. ?? 2009 The Authors Journal compilation ?? 2009 RAS.

  16. MEASUREMENT OF RADON CONCENTRATION IN DWELLINGS IN THE REGION OF HIGHEST LUNG CANCER INCIDENCE IN INDIA.

    Science.gov (United States)

    Zoliana, B; Rohmingliana, P C; Sahoo, B K; Mishra, R; Mayya, Y S

    2016-10-01

    Indoor radon/thoron concentration has been measured in Aizawl district, Mizoram, India, which has the highest lung cancer incidence rates among males and females in India. Simultaneously, radon flux emanated from the surrounding soil of the dwellings was observed in selected places. The annual average value of concentration of radon(thoron) of Aizawl district is 48.8(22.65) Bq m(-3) with a geometric standard deviation of 1.25(1.58). Measured radon flux from the soil has an average value of 22.6 mBq m(-2) s(-1) These results were found to be much below the harmful effect or action level as indicated by the World Health Organisation. On the other hand, food habit and high-level consumption of tobacco and its products in the district have been found to increase the risk of lung cancer incidence in the district. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Radon Measurements in Soils along the Coast of Accra from Teshie to Nyanyano, Southeastern Ghana

    Directory of Open Access Journals (Sweden)

    Paulina Ekua Amponsah

    2015-10-01

    Full Text Available A study has been undertaken along the coast of Accra (Teshie to Nyanyano in the Greater Accra Metropolitan Area to investigate the emission of soil radon gas in the area using Lenin Resin (LR 115 cellulose nitrate detectors. Twenty seven sampling points were considered for the investigation. A set of detectors were buried at a time and were replaced fortnightly for a period of 2 weeks. Three exposures were made at each location. Due to logistics constraints, the detectors were buried in phases over a period of 15 weeks. After the exposure period, the detectors were etched, air dried in the laboratory and the registered alpha tracks were counted using the Spark counter. The track density was calculated and the radon gas concentration was computed. The radon concentrations ranged from 1.40 kBqm-3 to 282.87 kBqm-3 for the period of monitoring. The average soil radon concentration measured during the period of the survey was 24.41 kBqm-3. Local earthquakes of magnitude ranging from 1.1 to 2.8 on the Richter scale were recorded during the study. Continuous monitoring of the gas could confirm high emanation with the activity of the coastal boundary fault.DOI: http://dx.doi.org/10.5755/j01.erem.71.2.7063

  18. Mapping of radon in Danish soils 1. Collection of basis data; Kortlaegning af radon i danske jordarter 1. Indsamling af grunddata

    Energy Technology Data Exchange (ETDEWEB)

    Gravesen, P.; Roll Jakobsen, P.; Kelstrup, N.; Ernstsen, V

    2000-07-01

    Danish soils are characterised as regards content of uranium, thorium, radium and radon. This has been done to supplement earlier collected data, to give an overview of the radon emanation from Danish soils, which is reasonably adequate for area and for the common soils. To supply the analysis of soil samples from the field, an airborne measurements of the radioactive radiation on Bornholm, has been carried out which can combine the point measurements, represented by the samples. The aim of the activities has been to prepare the geological basis to describe a radon potential map, where other radon data will to be included. 158 samples have been analysed. (EHS)

  19. Radon monitoring and hazard prediction in Ireland

    Science.gov (United States)

    Elio, Javier; Crowley, Quentin; Scanlon, Ray; Hodgson, Jim; Cooper, Mark; Long, Stephanie

    2016-04-01

    Radon is a naturally occurring radioactive gas which forms as a decay product from uranium. It is the largest source of natural ionizing radiation affecting the global population. When radon is inhaled, its short-lived decay products can interact with lung tissue leading to DNA damage and development of lung cancer. Ireland has among the highest levels of radon in Europe and eighth highest of an OECD survey of 29 countries. Every year some two hundred and fifty cases of lung cancer in Ireland are linked to radon exposure. This new research project will build upon previous efforts of radon monitoring in Ireland to construct a high-resolution radon hazard map. This will be achieved using recently available high-resolution airborne gamma-ray spectrometry (radiometric) and soil geochemistry data (http://www.tellus.ie/), indoor radon concentrations (http://www.epa.ie/radiation), and new direct measurement of soil radon. In this regard, legacy indoor radon concentrations will be correlated with soil U and Th concentrations and other geogenic data. This is a new approach since the vast majority of countries with a national radon monitoring programme rely on indoor radon measurements, or have a spatially limited dataset of soil radon measurements. Careful attention will be given to areas where an indicative high radon hazard based on geogenic factors does not match high indoor radon concentrations. Where such areas exist, it may imply that some parameter(s) in the predictive model does not match that of the environment. These areas will be subjected to measurement of radon soil gas using a combination of time averaged (passive) and time dependant (active) measurements in order to better understand factors affecting production, transport and accumulation of radon in the natural environment. Such mapping of radon-prone areas will ultimately help to inform when prevention and remediation measures are necessary, reducing the radon exposure of the population. Therefore, given

  20. Radon Testing for Safe Schools Act. Report (To Accompany S. 1697) from the Committee on Environment and Public Works, United States Senate, One Hundred First Congress, Second Session.

    Science.gov (United States)

    Congress of the U.S., Washington, DC. Senate Committee on Environment and Public Works.

    This report was written to accompany the Radon Testing for Safe Schools Act (S.1697), a bill that provides for radon testing of schools located in high risk radon areas and provides limited financial assistance to schools for mitigation of high levels of radon. A description of radon, its harmful effects, and the radon levels detected in schools…

  1. High radiation and desiccation tolerance of nitrogen-fixing cultures of the cyanobacterium Anabaena sp. strain PCC 7120 emanates from genome/proteome repair capabilities.

    Science.gov (United States)

    Singh, Harinder; Anurag, Kirti; Apte, Shree Kumar

    2013-10-12

    The filamentous nitrogen-fixing cyanobacterium, Anabaena sp. strain PCC 7120 was found to tolerate very high doses of (60)Co-gamma radiation or prolonged desiccation. Post-stress, cells remained intact and revived all the vital functions. A remarkable capacity to repair highly disintegrated genome and recycle the damaged proteome appeared to underlie such high radioresistance and desiccation tolerance. The close similarity observed between the cellular response to irradiation or desiccation stress lends strong support to the notion that tolerance to these stresses may involve similar mechanisms.

  2. Shallow circulation groundwater - the main type of water containing hazardous radon concentration

    Science.gov (United States)

    Przylibski, Tadeusz

    2010-05-01

    surface water forming a stream, radon very quickly escapes to the atmosphere. This is the main reason, that even in regions, where the bottoms of streams and rivers are formed by the rocks containing high amounts of radium (and uranium), surface waters very quickly lose radon escaping to the atmosphere. Concluding, surface waters cannot be the source of hazardous radon concentration. One may expect completely different situation in the case of groundwater. When the groundwater is exploited without any contact with the atmosphere, it contains higher concentration of Rn-222, than surface water in the same neighbourhood with regard to geological structure. Concentration of radon dissolved in groundwater depends first of all on the emanation coefficient of the reservoir rock. This coefficient may be calculated taking into account a few parameters, like cancentration of parent Ra-226 isotope in the reservoir rocks, effective porosity of the rock and the density of the grain framework of the rock. The way of radium atoms disposition in crystals or mineral grains of rock with reference to the pores and cracks filled with groundwater is also an important parameter. Calculations made by the author for more than 100 intakes of groundwater proove, that the highest values of emanation coefficient are characteristic for the rocks in the weathering zone - on the depths between surface level and 30 - 50 m below surface level. Groundwater exploited from the rocks of this zone contains the highest concentration of Rn-222. On the greater depths even high Ra-226 content in the reservoir rock does not affect to the Rn-222 concentration in groundwater flowing through this rock. Summing up, potentially the great radon concentration may contain groundwater of shallow circulation (up to ~50 m b.s.l.), flowing through weathered resrvoir rock with high content of parent Ra-226 isotope.

  3. Design, construction and testing of a radon experimental chamber; Diseno, construccion y pruebas de una camara experimental de radon

    Energy Technology Data Exchange (ETDEWEB)

    Chavez B, A.; Balcazar G, M

    1991-10-15

    To carry out studies on the radon behavior under controlled and stable conditions it was designed and constructed a system that consists of two parts: a container of mineral rich in Uranium and an experimentation chamber with radon united one to the other one by a step valve. The container of uranium mineral approximately contains 800 gr of uranium with a law of 0.28%; the radon gas emanated by the mineral is contained tightly by the container. When the valve opens up the radon gas it spreads to the radon experimental chamber; this contains 3 accesses that allow to install different types of detectors. The versatility of the system is exemplified with two experiments: 1. With the radon experimental chamber and an associated spectroscopic system, the radon and two of its decay products are identified. 2. The design of the system allows to couple the mineral container to other experimental geometries to demonstrate this fact it was coupled and proved a new automatic exchanger system of passive detectors of radon. The results of the new automatic exchanger system when it leave to flow the radon freely among the container and the automatic exchanger through a plastic membrane of 15 m. are shown. (Author)

  4. Ground-roll noise extraction and suppression using high-resolution linear Radon transform

    Science.gov (United States)

    Hu, Yue; Wang, Limin; Cheng, Feng; Luo, Yinhe; Shen, Chao; Mi, Binbin

    2016-05-01

    Ground-roll is a main type of strong noises in petroleum seismic exploration. Suppression of this kind of noise is essential to improve the signal-to-noise ratio of seismic data. In the time-offset (t-x) domain, the ground-roll noise and the effective waves (e.g., direct waves, reflections) overlap with each other in terms of time and frequency, which make it difficult to suppress ground roll noise in exploration seismic data. However, significant different features shown in the frequency-velocity (f-v) domain make it possible to separate ground roll noise and effective waves effectively. We propose a novel method to separate them using high-resolution linear Radon transform (LRT). Amplitude and phase information is preserved during the proposed quasi-reversible transformation. The reversibility and linearity of LRT provide a foundation for ground-roll noise suppression in the f-v domain. We extract the energy of ground-roll noise in the f-v domain, and transform the extracted part back to the t-x domain to obtain the ground-roll noise shot gather. Finally, the extracted ground-roll noise is subtracted from the original data arithmetically. Theoretical tests and a real world example have been implemented to illustrate that the ground-roll noise suppression can be achieved with negligible distortion of the effective signals. When compared with the adaptive ground-roll attenuation method and the K-L transform method, the real world example shows the superiority of our method in suppressing the ground-roll noise and preserving the amplitude and phase information of effective waves.

  5. Geological factors controlling radon hazardous concentration in groundwater

    Science.gov (United States)

    Przylibski, T. A.

    2009-04-01

    Radon waters are classified as waters containing more than 100 Bq/L of Rn-222. In many regions radon groundwaters are commonly used as a tap waters. Exploitation of radon groundwater without removing radon out of water in the intake may be hazardous for the consumers. Radon removing is relatively simple and cheap, and may be achieved trough the degassing of tapped water. The following factors are crucial for the genesis of radon (Rn-222) and changes in its concentration in groundwaters: the content of parent Ra-226 in the reservoir rock, the emanation coefficient of the reservoir rock, mixing of various groundwater components. Simplifying the geochemical characterisctics of Ra-226, one can say that the highest radium contents outside uranium deposits could be expected above all in crystalline rocks such as granites, ryolites and gneisses, and among sedimentary rocks - in fine-grained rocks - mudstones and clay rocks. Therefore the highest content of Rn-222 is characteristic of groundwaters flowing through the abovementioned rocks. What is very important for the genesis of groundwater dissolved Rn-222 is not only the total content of Ra-226 in the aquifer, but also the distribution of this isotope's atoms in relation to the surface of mineral grains (crystals) and crack surfaces. Only if Ra-226 atoms lie in the outer zone of grains (crystals), they can be the source of Rn-222 atoms released directly or indirectly into pores and fissures. If the pores and fissures are filled with free groundwater, then the radon dissolved in this water can migrate with it. Therefore particularly high Rn-222 concentration values can be expected in groundwaters circulating in zones of strongly cracked reservoir rocks, i.e. in the weathering zone, reaching the depth of several dozen meters below ground surface, as well as in zones of brittle tectonic deformations. The number of Rn-222 atoms formed in groundwater as a result of the decay of Ra-226 ion (Ra2+) dissolved in this water

  6. Methodology developed to make the Quebec indoor radon potential map.

    Science.gov (United States)

    Drolet, Jean-Philippe; Martel, Richard; Poulin, Patrick; Dessau, Jean-Claude

    2014-03-01

    This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal-Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal-Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m(3) in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists.

  7. A compressive sensing approach to the high-resolution linear Radon transform: application on teleseismic wavefields

    Science.gov (United States)

    Aharchaou, M.; Levander, A.

    2016-11-01

    We propose a new approach to the linear Radon transform (LRT) based on compressive sensing (CS) theory. This method can be used to extract signals of interest embedded in teleseismic measurements recorded by regional seismic arrays. We pose the problem of enhancing the resolution of the LRT as an inverse problem formulated in the frequency domain and solved according to a CS framework. We show how irregularity in the measurements along with sparsity constraints can be used to reach very compact and meaningful representations in the Radon domain, offering a benefit for both signal isolation and spatial interpolation during data reconstruction. We demonstrate the effectiveness of our approach and its benefits on both synthetic and USArray seismograms. This CS-based version of the LRT presents a valuable tool relevant for both global and exploration seismic processing, and which can be used as a basis for signal enhancement techniques exploiting irregularly sampled data.

  8. Natural radioactivity and radon specific exhalation rate of zircon sands

    Energy Technology Data Exchange (ETDEWEB)

    Righi, S.; Verita, S.; Bruzzi, L. [Bologna Univ., Centro Interdipartimentale di Ricerca per le Scienze Ambientali and Dipt. di Fisica, Ravenna (Italy); Albertazzi, A. [Italian Ceramic Center, Bologna (Italy)

    2006-07-01

    The study focuses on the radon emanation from zircon sands and their derivatives, which are widely used in many sectors of industry. In particular, the results obtained by experimental measurements on samples of zircon sands and zircon flours commonly used in Italian ceramic industries are reported. Zircon sands contain a significant concentration of natural radioactivity because Th and U may substitute zirconium in the zircon crystal lattice. The relevant routes of exposure of workers to T.E.N.O.R.M. from zircon materials are external radiation and internal exposure, either by inhalation of aerosols in dusty working conditions or by inhalation of radon in workplaces. The main objective of this investigation is to provide experimental data able to better calculate the internal exposure of workers due to radon inhalation. Zircon samples were surveyed for natural radioactivity, radon specific exhalation rate and emanation fraction. Measurements of radioactivity concentration were carried out using {gamma}-spectrometry. Methods used for determining radon consisted in determining the {sup 222}Rn activity accumulated in a vessel after a given accumulation build-up time. The average activity concentrations of {sup 238}U and {sup 232}Th in samples result about 2600 and 550 Bq kg-1, respectively; these concentrations are significantly higher than the world average noticed in soils, rocks and Earth crust. The {sup 222}Rn specific exhalation rates result very low probably due to the low porosity of the material and the consequent difficulty for radon to be released from the zircon crystal lattice. (author)

  9. Long-term measurements of residential radon, thoron, and thoron progeny concentrations around the Chhatrapur placer deposit, a high background radiation area in Odisha, India.

    Science.gov (United States)

    Omori, Yasutaka; Prasad, Ganesh; Sorimachi, Atsuyuki; Sahoo, Sarata Kumar; Ishikawa, Tetsuo; Vidya Sagar, Devulapalli; Ramola, Rakesh Chand; Tokonami, Shinji

    2016-10-01

    The Chhatrapur placer deposit is found in a high background radiation area which has been recently identified on the southeastern coast of India. Previously, some geochemical studies of this area were carried out to assess external dose from radionuclides-bearing heavy mineral sands. In this study, radon, thoron and thoron progeny concentrations were measured in about 100 dwellings during three seasons (autumn-winter, summer, and rainy) in a 10- to 12-month period and annual doses due to inhalation of them were evaluated. The measurements were made by passive-type radon-thoron discriminative detectors and thoron progeny detectors in which solid state nuclear track detectors were deployed. The results show that radon and thoron concentrations differ by one order of magnitude depending on exposure periods, while thoron progeny concentration is nearly constant throughout the year. Since thorium-rich sand is distributed in the studied area, exposure to thoron is equal to, or exceeds, exposure to radon and is not negligible for dose evaluation. Based on the measurements, doses due to inhalation of radon and thoron are evaluated as 0.1-1.6 mSv y(-1) and 0.2-3.8 mSv y(-1), respectively. The total dose is 0.8-4.6 mSv y(-1), which is the same order of magnitude as the worldwide value. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Methodology developed to make the Quebec indoor radon potential map

    Energy Technology Data Exchange (ETDEWEB)

    Drolet, Jean-Philippe, E-mail: jean-philippe.drolet@ete.inrs.ca [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Martel, Richard [Institut national de la recherche scientifique, Eau Terre Environnement Research Centre (ETE-INRS), 490 de la Couronne, G1K 9A9 Quebec (Canada); Poulin, Patrick [Institut national de santé publique du Québec (INSPQ), 945 avenue Wolfe, G1V 5B3 Quebec (Canada); Dessau, Jean-Claude [Agence de la santé et des services sociaux des Laurentides, 1000 rue Labelle, J7Z 5 N6 Saint-Jérome (Canada)

    2014-03-01

    This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal–Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal–Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m{sup 3} in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists. - Highlights: • 5 radiogeochemical datasets were used to map the geogenic indoor radon potential. • An indoor radon potential was determined for

  11. los servicios en redes E-MAN

    Directory of Open Access Journals (Sweden)

    Eduardo de la Cruz Gámez

    2006-01-01

    Full Text Available Ethernet, al evolucionar a través del tiempo, ha presentado la necesidad de un mejor desempeño en el tráfico de datos; propuestas como la implementación del protocolo 802.1p ofrecen hasta cierta medida un control de la calidad de los servicios (QoS, pero al crecer la red Ethernet a ambientes metropolitanos (e-man, surgen nuevos retos. Este trabajo evalúa los parámetros de desempeño necesarios para caracterizar la red e-man, y analiza un nuevo procedimiento para abordar los problemas de la calidad de los servicios; este trabajo también analiza el comportamiento del desempeño de un modelo de simulación basado en el núcleo de backbone de una red metropolitana rpr.

  12. Shallow circulation groundwater – the main type of water containing hazardous radon concentration

    Directory of Open Access Journals (Sweden)

    T. A. Przylibski

    2011-06-01

    Full Text Available The main factors affecting the value of 222Rn activity concentration in groundwater are the emanation coefficient of reservoir rocks (Kem, the content of parent 226Ra in these rocks (q, changes in the volume and flow velocity as well as the mixing of various groundwater components in the circulation system. The highest values of 222Rn activity concentration are recorded in groundwaters flowing towards an intake through strongly cracked reservoir rocks undergoing weathering processes. Because of these facts, waters with hazardous radon concentration levels, i.e. containing more than 100 Bq dm−3 222Rn, could be characterised in the way that follows. They are classified as radon waters, high-radon waters and extreme-radon waters. They belong to shallow circulation systems (at less than a few dozen metres below ground level and are contemporary infiltration waters, i.e. their underground flow time ranges from several fortnights to a few decades. Because of this, these are usually poorly mineralised waters (often below 0.2–0.5 g dm−3. Their resources are renewable, but also vulnerable to contamination.

    Waters of this type are usually drawn from private intakes, supplying water to one or at most a few households. Due to an increased risk of developing lung tumours, radon should be removed from such waters when still in the intake. To achieve this aim, appropriate legislation should be introduced in many countries.

  13. Radiological risk assessment of environmental radon

    Science.gov (United States)

    Khalid, Norafatin; Majid, Amran Ab; Yahaya, Redzuwan; Yasir, Muhammad Samudi

    2013-11-01

    Measurements of radon gas (222Rn) in the environmental are important to assess indoor air quality and to study the potential risk to human health. Generally known that exposure to radon is considered the second leading cause of lung cancer after smoking. The environmental radon concentration depends on the 226Ra concentration, indoor atmosphere, cracking on rocks and building materials. This study was carried out to determine the indoor radon concentration from selected samples of tin tailings (amang) and building materials in an airtight sealed homemade radon chamber. The radiological risk assessment for radon gas was also calculated based on the annual exposure dose, effective dose equivalent, radon exhalation rates and fatal cancer risk. The continuous radon monitor Sun Nuclear model 1029 was used to measure the radon concentration emanates from selected samples for 96 hours. Five types of tin tailings collected from Kampar, Perak and four samples of building materials commonly used in Malaysia dwellings or building constructions were analysed for radon concentration. The indoor radon concentration determined in ilmenite, monazite, struverite, xenotime and zircon samples varies from 219.6 ± 76.8 Bq m-3 to 571.1 ± 251.4 Bq m-3, 101.0 ± 41.0 Bq m-3 to 245.3 ± 100.2 Bq m-3, 53.1 ± 7.5 Bq m-3 to 181.8 ± 9.7 Bq m-3, 256.1 ± 59.3 Bq m-3 to 652.2 ± 222.2 Bq m-3 and 164.5 ± 75.9 Bq m-3 to 653.3 ± 240.0 Bq m-3, respectively. Whereas, in the building materials, the radon concentration from cement brick, red-clay brick, gravel aggregate and cement showed 396.3 ± 194.3 Bq m-3, 192.1 ± 75.4 Bq m-3, 176.1 ± 85.9 Bq m-3 and 28.4 ± 5.7 Bq m-3, respectively. The radon concentration in tin tailings and building materials were found to be much higher in xenotime and cement brick samples than others. All samples in tin tailings were exceeded the action level for radon gas of 148 Bq m-3 proposed by EPA except monazite 0.15 kg, struverite 0.15 kg and 0.25 kg. Whereas

  14. Radon risk in the house; Il rischio radon nelle abitazioni

    Energy Technology Data Exchange (ETDEWEB)

    Bressa, G. [Padua Univ., Padua (Italy). Dipt. di Farmacologia e Anestesiologia, Lab. di Tossicologia

    2001-04-01

    Radon was discovered in 1900, but its potential dangerousness for man was fully understood only in 1950. Being a radioactive natural gas - and therefore particularly dangerous - radon results from the long decay chain of radionuclides, such as thorium and radium. Some igneous rocks (granite, tufa and lava) as well as coal are considered to be the main sources of this radionuclide. A number of epidemiologic studies have shown the carcinogenicity of this element, particularly among miners and workers subjected to high level exposure in confined spaces such as basements, garages, cellars, etc. There are, however, some techniques to remove radon in order to reduce exposure to minimum values. [Italian] Il radon fu scoperto nel 1900, ma solo nel 1950 si comprese la sua potenziale pericolosita' per l'uomo. Il radon e' particolarmente pericoloso essendo un gas naturale radioattivo. Esso proviene dalla lunga catena di decadimento di radionuclidi come il torio e di radio. Sorgenti di tale radionuclide sono da considerarsi principalmente alcune rocce ignee (graniti, tufi e lave) e il carbone. Diversi studi epidemiologici hanno evidenziato la cancerogenicita' di tale elemento, specie tra i minatori e soggetti esposti ad alti livelli in ambienti confinati quali scantinati, garage sotterranei, ecc.. Esistono comunque tecniche di intervento per la rimozione del gas radon in modo tale da ridurre l'esposizione a valori minimi.

  15. Radon Like atmospheric pollutant; El gas Radon como contaminante atmosferico

    Energy Technology Data Exchange (ETDEWEB)

    Quindos Poncela, L. S.; Sainz Fernandez, C.; Quindos Lopez, L.; Fuente Merino, I.; Arteche, J. L.

    2008-07-01

    In this work different aspects about the problem of the radon in dwellings are approached. This gas of natural origin is virtually present in all the soils in the earths crust due to the presence of uranium and radium in the composition of them. Depending on architectural factors and of occupancy habits of the house, high concentrations of this gas can be reached indoors. In these situations, there is a quantifiable increment of the risk of developing lung cancer in the inhabitants of the housing. In the last years the methodological improvements in the realization of epidemiologic studies have led to the obtaining of scientific evidence about the relationship between the presence of indoor radon and the risk of lung cancer. This relationship fund years ago in workers of uranium mines, has been corroborated in the case of the residential radon by the light of several recent meta-analysis performed on groups of epidemiologic studies. More than 4000 radon measurements have been carried out in spain during the las 25 years. A summary of the results obtained from the main national radon surveys are also presented, as well as the criteria recently established by the Spanish Nuclear Safety Council concerning radon action levels in dwellings and workplaces. (Author) 18 refs.

  16. Long term continuous radon monitoring in a seismically active area

    CERN Document Server

    Piersanti, A; Galli, G

    2015-01-01

    We present the results of a long term, continuous radon monitoring experiment started in April 2010 in a seismically active area, affected during the 2010-2013 data acquisition time window by an intense micro seismic activity and by several small seismic events. We employed both correlation and cross-correlation analyses in order to investigate possible relationship existing between the collected radon data, seismic events and meteorological parameters. Our results do not support the feasibility of a robust one-to-one association between the small magnitude earthquakes characterizing the local seismic activity and single radon measurement anomalies, but evidence significant correlation patterns between the spatio-temporal variations of seismic moment release and soil radon emanations, the latter being anyway dominantly modulated by meteorological parameters variations.

  17. The Reference Laboratory for Radon Gas Activity Concentration Measurements at PSI; Das Referenzlabor fuer Radongas-Konzentrationsmessungen am PSI

    Energy Technology Data Exchange (ETDEWEB)

    Schuler, Christoph

    1998-09-01

    Active or passive radon gas measuring instruments are exposed during intercomparison exercises in the radon chamber of the Reference Laboratory for Radon Gas Concentration Measurements at Paul Scherrer Institut: The traceability of radon gas measurements to nationally and internationally acknowledged standards is inspected in the reference atmosphere of the chamber with calibrated {sup 222}Rn activity concentration. The use of secondary standards guarantees the traceability of the radon chamber reference atmosphere. Besides the principal secondary standard, a radon gas standard (secondary standard I), a {sup 226}Ra standard solution (secondary standard II) and a {sup 222}Rn emanation standard (secondary standard III) are used. The {sup 222}Rn activity delivered by one of these standards is quantitatively transferred into a reference volume and hence converted to an activity concentration serving for the calibration of a measuring instrument transfer standard consisting of scintillation cell and counter. By this way, the transfer standard calibration is related and traceable to the internationally acknowledged primary standard laboratories National Institute of Standards and Technology, Gaithersburg, Maryland (U.S.A.) or National Physical Laboratory, Teddington, Middlesex (UK). The calibrated transfer standard is then used to calibrate the radon gas activity concentration in the radon chamber. For a single grab sampling determination of the {sup 222}Rn activity concentration in the radon chamber with the transfer standard, the estimation of Type A and Type B uncertainties yields a relative expanded uncertainty (95% confidence level) of minimum 3% for high concentration levels (10 kBqm{sup -3}) and maximum 30% for low concentration levels (0.2 kBqm{sup -3}). Extended evaluations of the reproducibility of calibration factor measurements obtained by calibration of the transfer standard with the secondary standards I, II and III show a very good reproducibility quality

  18. Multidisciplinary analysis of Finnish esker sediment in radon source identification.

    Science.gov (United States)

    Breitner, Dániel; Turtiainen, Tuukka; Arvela, Hannu; Vesterbacka, Pia; Johanson, Bo; Lehtonen, Marja; Hellmuth, Karl-Heinz; Szabó, Csaba

    2008-11-01

    In order to define the naturally-occurring radioactive materials that are the source of radon in natural environments, a comprehensive analytical (geochemical, physical and chemical) methodology was employed to study sand samples from the Hollola esker in the city of Hollola (Lahti area, Finland). Techniques such as gamma-spectrometry, emanation measurements, sequential chemical extraction, scanning electron microscopy (SEM), electron probe microanalyses (EPMA) and inductively-coupled plasma mass spectrometry (ICP-MS) were used to determine the potential source of radon. Monazite and xenotime, uranium- and thorium-bearing minerals and potential radon sources, occurred in significant amounts in the samples and were also the main reason for the distribution of uranium and thereby radium in separate grain-size fractions. Following deposition, the esker sand has been exposed to no significant weathering, and radium has not therefore been much separated from uranium. However, considering its non-compatibility with crystal lattices, it was recognized rather in easily leachable species (44% of the total (226)Ra) than uranium (21% of the total (238)U) in our analyses. The smallest grain-size fraction of the esker sand had a higher emanation power (0.24) than the other fractions (around 0.17). Due to the small relative proportion of this fraction, however, it contributed only slightly to the total emanation (4%). The emanation power of the leachable species was about three times higher (ca. 0.20) than that of the species tightly bound to the crystal lattice (ca. 0.07).

  19. Experimental assessment of indoor radon and soil gas variability: the RADON project

    Science.gov (United States)

    Barbosa, S. M.; Pereira, A. J. S. C.; Neves, L. J. P. F.; Steinitz, G.; Zafrir, H.; Donner, R.; Woith, H.

    2012-04-01

    Radon is a radioactive noble gas naturally present in the environment, particularly in soils derived from rocks with high uranium content. Radon is formed by alpha decay from radium within solid mineral grains, but can migrate via diffusion and/or advection into the air space of soils, as well as into groundwater and the atmosphere. The exhalation of radon from the pore space of porous materials into the atmosphere of indoor environments is well known to cause adverse health effects due to the inhalation of radon's short-lived decay products. The danger to human health is particularly acute in the case of poorly ventilated dwellings located in geographical areas of high radon potential. The RADON project, funded by the Portuguese Science Foundation (FCT), aims to evaluate the temporal variability of radon in the soil and atmosphere and to examine the influence of meteorological effects in radon concentration. For that purpose an experimental monitoring station is being installed in an undisturbed dwelling located in a region of high radon potential near the old uranium mine of Urgeiriça (central Portugal). The rationale of the project, the set-up of the experimental radon monitoring station, and preliminary monitoring results will be presented.

  20. Environmental effect of radon from waste rock piles at closed uranium mine

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Sadaaki; Ito, Kimio; Ishimori, Yuu; Nakajima, Yuuji [Power Reactor and Nuclear Fuel Development Corp., Kamisaibara, Okayama (Japan). Ningyo Toge Works

    1997-04-01

    The radon concentrations at working area had been measured during uranium exploration by Power Reactor and Nuclear Fuel Development Corporation (PNC). Although the uranium exploration was closed by 1987, the measurements of environmental radon and the confirmation of public dose under 1 mSv/year out of supervising area has been necessary by the regulation since 1989, the year of the change of Japanese mine safety law. However radon exists in natural environment, it`s quite difficult to distinguish the radon from closed uranium mine from natural`s. Therefore the effective doses were estimated by the calculations using the atmospheric dispersion models, and by the measurements of radon emanation from the waste rock area of closed uranium mines. The radon influence from the waste rock was also investigated by the tracer gas dispersion experiments. Consequently the effective doses from the mining facilities were confirmed under the public limits 1 mSv/year of the regulations by this study. (author)

  1. Laboratory research on tailings stabilization methods and their effectiveness in radiation containment. [Uranium, reduction of radon exhalation

    Energy Technology Data Exchange (ETDEWEB)

    Macbeth, P.J.; Jensen, C.M.; Rogers, V.C.; Overmyer, R.F.

    1978-04-01

    This report describes a study of various methods, techniques, and materials for stabilizing uranium mill tailings to reduce radon exhalation. Radon emanation from tailings particles, radon exhalation from tailings, and methods that could be used to reduce radon exhalation from tailings piles are discussed. Surface radon flux and soil gas concentrations were measured in experiment chambers or columns consisting of uranium tailings and various types and thicknesses of cover materials. The applicability of diffusion theory was examined and effective diffusion coefficients were determined for clay, soil, and sand. The variation of radon flux with atmospheric effects and moisture also was investigated. The effectiveness of several types of chemical stabilizers for both volumetric and surface application in reducing radon exhalation is reported. Some volumetric stabilizers reduced radon flux by 90 percent or more. Radon flux was determined through the use of charcoal gas mask canisters, and flux accumulation chambers sampled by Lucas cells. Both of these techniques are described. Soil gas concentration was sampled with Lucas cells and counted with a sodium iodide scintillation spectrometer system. Emanating power of uranium tailings was measured for several particle sizes and found to be relatively constant at about 20 percent. Two types of grasses were found that would grow in tailings if sufficient water and fertilizer were provided. The effect of vegetation on radon exhalation was not determined.

  2. The Pollino 2012 seismic sequence: clues from continuous radon monitoring

    Science.gov (United States)

    Piersanti, Antonio; Cannelli, Valentina; Galli, Gianfranco

    2016-09-01

    The 2012 Pollino (Calabria, Italy) seismic sequence, culminating in the Mw 5.2 earthquake of 25 October 2012, is investigated, exploiting data collected during a long-term continuous radon monitoring experiment performed in the epicentral area from late 2011 to the end of 2014. We analyse data collected both using a phenomenological approach based on quantitative evidence and a purely numerical analysis including the following: (i) correlation and cross-correlation investigations; (ii) an original approach aimed at limiting the impact of meteorological parameters variations on the interpretation of measured radon levels; (iii) a change point analysis; (iv) the implementation of an original detection algorithm aimed at highlighting the connections between radon emission variations and major seismic events occurrence. Results from both approaches suggest that radon monitoring stations can be subject to massive site effects, especially regarding rainfall, making data interpretation harder. The availability of long-term continuous measurements is crucial to precisely assess those effects. Nevertheless, statistical analysis shows a viable approach for quantitatively relating radon emanation variations to seismic energy release. Although much work is still needed to make radon time series analysis a robust complement to traditional seismological tools, this work has identified a characteristic variation in radon exhalation during the preparation process of large earthquakes.

  3. Radon in homes of the Portland, Oregon Area: Radon data from local radon testing companies collected by CRM (Continuous Radon Measurement) machines

    Science.gov (United States)

    Whitney, H.; Lindsey, K.; Linde, T.; Burns, S. F.

    2013-12-01

    Students from the Department of Geology at Portland State University paired up with the Oregon Health Authority to better understand radon gas values in homes of the Portland metropolitan area. This study focuses on radon values collected by continuous radon measurement (CRM) machines, taken by local radon testing companies. The local companies participating in this study include Alpha Environmental Services, Inc., Cascade Radon, Environmental Works, The House Detectives, LLC, and Soil Solutions Environmental Services, Inc. In total, 2491 radon readings spanning across 77 zip codes were collected from local companies in the Portland metropolitan area. The maximum value, average value, percentage of homes greater than 4 pCi/L and total rank sum was calculated and used to determine the overall radon potential for each zip code (Burns et al., 1998). A list and four maps were produced showing the results from each category. Out of the total records, 24 zip codes resulted in high radon potential and the average reading for the entire Portland Metropolitan area was 3.7 pCi/L. High potential zip codes are thought to be a result of sand and gravel (Missoula Flood deposits) and faults present in the subsurface. The CRM data was compared with both long-term and short-term data provided by the Oregon Health Authority to validate radon potentials in each zip code. If a home is located in a zip code with high or moderate radon potential across two types of data sets, it is recommended that those homes be tested for radon gas.

  4. Assessment of indoor radon gas concentration change of college

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hoon Hee; Jeong, Eui Hwan; Kim, Hak Jae; Lyu, Kang Yeul [Dept. of of Radiological Technology, Shingu College, Seongnam (Korea, Republic of); Lee, Ju Young [Dept. of Radiological Technology, Songho College, Hoengseong (Korea, Republic of)

    2017-03-15

    The purpose of this study was to assess the impact by comparing the concentration of indoor radon and look for ways to lower the concentration of indoor radon gas measurements of three variables, the year of completion, volume of the building and ventilation. Measurement target is six classrooms on the sixth floor of building that was constructed in 1973 and was extended in 2011. Selected classroom's volume is different. Four classrooms were selected to compare the radon concentration in accordance with the year of completion, Classrooms that is same year of completion were selected to compare the radon concentration in accordance with the volume, six classroom was performed closure and ventilation to compare radon concentration according to ventilation. Radon concentrations in accordance with the year of building completion showed a high concentration of radon in a building recently built. Also, Radon concentration in volume is high the smaller the volume. Radon concentration change according to ventilation showed a reduction of about 80% when the ventilation than during closing. Especially, The radon concentrations were high detected while the recently year of building completion and the smaller volume. Ventilation of the three variables is considered that can be expected to exposure reduction effect by radon affecting the greatest radon concentration reduction.

  5. Radon Reduction Methods: A Homeowner's Guide.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    The U.S. Environmental Protection Agency (EPA) is studying the effectiveness of various ways to reduce high concentrations of radon in houses. This booklet was produced to share what has been learned with those whose radon problems demand immediate action. The booklet describes nine methods that have been tested successfully--by EPA and/or other…

  6. Radon in soil concentration levels in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, N.; Tamez, E.; Mena, M

    1991-09-15

    Radon in soil surveys in Mexico have been carried out since 1974 both for uranium prospectus and to correlate mean values of the gas emanation with local telluric behaviour. The mapping includes the northern uranium mining region, the Mexican Neo volcanic Belt, the coastal areas adjacent to the zone of subduction of the Cocos Plate under the North American Plate, some of the active volcanoes of Southern Mexico and several sedimentary valleys in Central Mexico. Recording of {sup 222} Rn alpha decay is systematically performed with LR115 track detectors. Using mean values averaged over different observation periods at fixed monitoring stations, a radon in soil map covering one third of the Mexican territory is presented. The lowest mean values have been found in areas associated with active volcanoes. The highest levels are found in uranium ore zones. Intermediate values are obtained in regions with enhanced hydrothermal activity and stations associated with intrusive rocks. (Author)

  7. Method for radon measurement in the subsoil in geothermal prospectus; Metodos de medicion de radon en el subsuelo en prospeccion geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar G, M

    1991-02-15

    The present formless describe the technique for radon measurement in the underground, being able to be used as an additional study in the geothermal prospecting. This methodology has been developed in the National Institute of Nuclear Research of Mexico using a film of cellulose nitrate to detect those emanated alpha particles, by the Rn (222). By means of the trace account in this films its settle down the present radon levels in the underground. The present method thinks about as an alternating one to overcome in it leaves the limitations found in the development of the methodology using a radon emanometer ETR-1, of the trade mark SCINTREX. The radon detected by plastics is also an integral method of measuring in a geothermal field that avoids the problems of variations of radon to pluvial precipitations and barometric variations. These variations affect the results strongly when it is used the punctual sampler as it is the ETR-1. (Author)

  8. Field experience with soil gas mapping using Japanese passive radon/thoron discriminative detectors for comparing high and low radiation areas in Serbia (Balkan Region).

    Science.gov (United States)

    Zunić, Zora S; Janik, Miroslaw; Tokonami, Shinji; Veselinović, Nenad; Yarmoshenko, Ilia V; Zhukovsky, Michael; Ishikawa, Tetsuo; Ramola, Rakesh C; Ciotoli, Giancarlo; Jovanović, Peter; Kozak, Krzysztof; Mazur, Jadwiga; Celiković, Igor; Ujić, Predrag; Onischenko, Aleksandra; Sahoo, Sarat K; Bochicchio, Francesco

    2009-07-01

    Based on results of fieldwork in the Balkan Region of Serbia from 2005 to 2007, soil gas radon and thoron concentrations as well as gamma dose rates were measured. Campaigns were conducted in two different geological regions: Niska Banja, considered a high natural radiation area, and Obrenovac around the TentB Thermal Power Plant (TPP), a low natural radiation area. Radon and thoron gas measurements were made by using two types of Japanese passive radon/thoron detectors, which included GPS data and gamma dose rates. The concentrations of soil radon gas in Niska Banja ranged from 1.8 to 161.1 kBq m(-3), whereas the concentrations for soil thoron gas ranged from 0.9 to 23.5 kBq m(-3). The gamma dose rates varied from 70 to 320 nGy h(-1). In the TentB area, radon concentration was found to range from 0.8 to 24.9 kBq m(-3) and thoron from 0.6 to 1.9 kBq m(-3). The gamma dose rate ranged from 90 to 130 nGy h(-1). In addition, the natural radioactivity of the soil was investigated at the low background area. The radium and thorium contents in collected soil samples ranged from 23 to 58 and 33 to 67 Bq kg(-1), respectively. As a result of correlation analyses between the measured values, the highest correlation coefficient (R > 0.95) was found for thorium in the soil and the thoron gas concentration.

  9. Evaluation of the open vial method in the radon measurement; Evaluacion del metodo del vial abierto en la medicion de radon

    Energy Technology Data Exchange (ETDEWEB)

    Lopez del Rio, H.; Davila R, J. I.; Mireles G, F., E-mail: hlopezdelrio@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-10-15

    The open vial method is a simple technique, under-utilized but that take advantage of the great radon solubility in organic solvents, therefore applies in the measurement of the radon concentration exhaled in soil. The method consists on the exposition to the gas radon of an open vial with scintillating solution. An integral mathematical model for indoors that describes the emanation processes and gas radon exhalation was developed, as well as the radon dissolution in the scintillation liquid, besides obtaining the characteristic parameters of the experimental system proposed for the radon concentration calculation exhaled by soils. Two experimental arrangements were designed with exposition cameras of 12 and 6 L and quantity of different soil. The open vial was prepared with a mixture of 8 ml of deionized water and 12 ml of scintillation liquid OptiPhase Hi Safe 3 in polyethylene vials; the measurements of the dissolved radon were carried out in scintillation liquid equipment. As a result, on average 2.0% of the exhaled radon is dissolved in the open vial and the dissolved fraction is independent of the experimental arrangement. Also was observed that the exposition time does not affect the radon dissolution significantly, in correspondence with the reported in the literature. (Author)

  10. Workshop on dosimetry for radon and radon daughters

    Energy Technology Data Exchange (ETDEWEB)

    Turner, J.E.; Holoway, C.F.; Loebl, A.S. (eds.)

    1978-05-01

    Emphasis is placed on the dosimetry for radon and daughters, rather than on monitoring and instrumentation. The objectives of the meeting were to exchange scientific information, to identify problem areas in radon-daughter dosimetry, and to make any observations or recommendations by the participants through issuance of this report. The discussion topics included the history of dosimetry for radon and daughters, human data, aerosols, deposition and movement in the respiratory tract, dose calculations, dose-to-working-level-month (WLM) conversion factors, animal experiments, and the development of regulations and remedial criteria for reducing population exposures to radon daughters. This report contains a summary of Workshop discussions plus individual statements contributed by several of the participants. The outstanding problem areas from the standpoint of dosimetry appear to involve the appropriate lung organ mass to be used (average lung-tissue dose vs. high-level local dose); recognition of the discrete, rather than continuous, structure of the mucus; lack of knowledge about lung clearance; the variability of dose with the degree of disequilibrium and the unattached fraction of radon daughters for a given WLM; and questions about the character of uranium mine atmospheres actually breathed in the older mines from which much of the epidemiological information originates. The development of criteria for taking remedial action to reduce exposures involves additional concerns of basing long-term risk assessment on short-term sampling and applying WLM data for miners to general populations.

  11. Development of a low-level radon reference chamber; Entwicklung einer Low-Level-Radon-Referenzkammer

    Energy Technology Data Exchange (ETDEWEB)

    Linzmaier, Diana

    2013-01-04

    The naturally occurring, radioactive noble gas radon-222 exists worldwide in different activity concentrations in the air. During the decay of radon-222, decay products are generated which are electrically charged and attach to aerosols in the air. Together with the aerosols, the radon is inhaled and exhaled by humans. While the radon is nearly completely exhaled, ca. 20 % of the inhaled aerosols remain in the lungs in one breath cycle. Due to ionizing radiation, in a chain of events, lung cancer might occur. Consequently, radon and its decay products are according to the current findings the second leading cause of lung cancer. At the workplace and in the home measurements of radon activity concentration are performed to determine the radiation exposition of humans. All measurement devices for the determination of radon activity concentration are calibrated above 1000 Bq/m{sup 3}, even though the mean value of the present investigation in Germany shows only 50 Bq/m{sup 3}. For the calibration of measurement devices in the range below 1000 Bq/m{sup 3} over a long time period, the generation of a stable reference atmosphere is presented in this work. Due to a long term calibration (t>5 days) of the measurement devices, smaller uncertainties result for the calibration factor. For the calibration procedure, a so-called low-level radon reference chamber was set up and started operation. The generation of a stable reference atmosphere is effected by means of emanation sources which consist of a radium-226 activity standard. On the basis of {gamma}-spectrometry, the effective emanation coefficient ofthe emanation sources is determined. The traceability of the activity concentration in the reference volume is realized via the activity ofthe radium-226, the emanation coefficient and the volume. With the emanation sources produced, stable reference atmospheres within the range of 150 Bq/m{sup 3} to 1900 Bq/m{sup 3} are achieved. For the realization, maintenance and

  12. The Radon Monitoring System in Daya Bay Reactor Neutrino Experiment

    CERN Document Server

    Chu, M C; Kwok, M W; Kwok, T; Leung, J K C; Leung, K Y; Lin, Y C; Luk, K B; Pun, C S J

    2016-01-01

    We developed a highly sensitive, reliable and portable automatic system (H$^{3}$) to monitor the radon concentration of the underground experimental halls of the Daya Bay Reactor Neutrino Experiment. H$^{3}$ is able to measure radon concentration with a statistical error less than 10\\% in a 1-hour measurement of dehumidified air (R.H. 5\\% at 25$^{\\circ}$C) with radon concentration as low as 50 Bq/m$^{3}$. This is achieved by using a large radon progeny collection chamber, semiconductor $\\alpha$-particle detector with high energy resolution, improved electronics and software. The integrated radon monitoring system is highly customizable to operate in different run modes at scheduled times and can be controlled remotely to sample radon in ambient air or in water from the water pools where the antineutrino detectors are being housed. The radon monitoring system has been running in the three experimental halls of the Daya Bay Reactor Neutrino Experiment since November 2013.

  13. Radon exposure and oropharyngeal cancer risk.

    Science.gov (United States)

    Salgado-Espinosa, Tania; Barros-Dios, Juan Miguel; Ruano-Ravina, Alberto

    2015-12-01

    Oropharyngeal cancer is a multifactorial disease. Alcohol and tobacco are the main risk factors. Radon is a human carcinogen linked to lung cancer risk, but its influence in other cancers is not well known. We aim to assess the effect of radon exposure on the risk of oral and pharyngeal cancer through a systematic review of the scientific literature. This review performs a qualitative analysis of the available studies. 13 cohort studies were included, most of them mortality studies, which analysed the relationship between occupational or residential radon exposure with oropharyngeal cancer mortality or incidence. Most of the included studies found no association between radon exposure and oral and pharyngeal cancer. This lack of effect was observed in miners studies and in general population studies. Further research is necessary to quantify if this association really exists and its magnitude, specially performing studies in general population, preferably living in areas with high radon levels.

  14. Radon and thoron concentrations in public workplaces in Brisbane, Australia.

    Science.gov (United States)

    Alharbi, Sami H; Akber, Riaz A

    2015-06-01

    Radon and thoron are radioactive gases that can emanate from soil and building materials, and it can accumulate in indoor environments. The concentrations of radon and thoron in the air from various workplace categories in Brisbane, Australia were measured using an active method. The average radon and thoron concentrations for all workplace categories were 10.5 ± 11.3 and 8.2 ± 1.4 Bq m(-3), respectively. The highest radon concentration was detected in a confined area, 86.6 ± 6.0 Bq m(-3), while the maximum thoron level was found in a storage room, 78.1 ± 14.0 Bq m(-3). At each site, the concentrations of radon and thoron were measured at two heights, 5 cm and 120 cm above the floor. The effect of the measurement heights on the concentration level was significant in the case of thoron. The monitoring of radon and thoron concentrations showed a lower radon concentration during work hours than at other times of the day. This can be attributed to the ventilation systems, including the air conditioner and natural ventilation, which normally operate during work hours. The diurnal variation was less observed in the case of thoron, as the change in its concentration during and after the working hours was insignificant. The study also investigated the influence of the floor level and flooring type on indoor radon and thoron concentrations. The elevated levels of radon and thoron were largely found in basements and ground floor levels and in rooms with concrete flooring.

  15. STUDY OF RADON FLUX FROM SOIL IN BUDHAKEDAR REGION USING SRM.

    Science.gov (United States)

    Bourai, A A; Aswal, Sunita; Kandari, Tushar; Kumar, Shiv; Joshi, Veena; Sahoo, B K; Ramola, R C

    2016-10-01

    In the present study, the radon flux rate of the soil is measured using portable radon monitor (scintillation radon monitor) in the Budhakedar region of District Tehri, India. The study area falls along a fault zone named Main Central Thrust, which is relatively rich in radium-bearing minerals. Radon flux rate from the soil is one of the most important factors for the evaluation of environmental radon levels. The earlier studies in the Budhakedar region shows a high level of radon (>4000 Bq m(-3)). Hence, it is important to measure the radon flux rate. The aim of the present study is to calculate the average estimate of the surface radon flux rate as well as the effective mass exhalation rate. A positive correlation of 0.54 was found between radon flux rate and radon mass exhalation rate. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Health Risk of Radon

    Science.gov (United States)

    ... Radon in Homes EPA 402-R-03-003. Summary Fact Sheet on the updated risk assessment . Top of Page Former U.S. Surgeon General ... WHO) launched an international radon project to help countries increase ... reduce radon-related risks. The U.S. EPA is one of several government ...

  17. An assessment of gas emanation hazard using a geographic information system and geostatistics.

    Science.gov (United States)

    Astorri, F; Beaubien, S E; Ciotoli, G; Lombardi, S

    2002-03-01

    This paper describes the use of geostatistical analysis and GIS techniques to assess gas emanation hazards. The Mt. Vulsini volcanic district was selected for this study because of the wide range of natural phenomena locally present that affect gas migration in the near surface. In addition, soil gas samples that were collected in this area should allow for a calibration between the generated risk/hazard models and the measured distribution of toxic gas species at surface. The approach used during this study consisted of three general stages. First data were digitally organized into thematic layers, then software functions in the GIS program "ArcView" were used to compare and correlate these various layers, and then finally the produced "potential-risk" map was compared with radon soil gas data in order to validate the model and/or to select zones for further, more-detailed soil gas investigations.

  18. Durability of radon remedial actions

    Energy Technology Data Exchange (ETDEWEB)

    Naismith, S. [National Radiological Protection Board, Chilton (United Kingdom)

    1997-10-01

    In the UK, approximately 3600 householders are believed to have taken action to reduce high radon concentrations in their homes. In 1993 a number of those householders who had taken successful remedial actions were invited to participate in a study of durability of radon remedial actions. This involved the radon concentration being remeasured annually. Results for 26 such homes where a complete set of data are available and a further 32 with incomplete data are discussed here. All remedial actions were shown to remain durable during a period of 5 years. The largest variation in effectiveness was found in houses with natural ventilation of the underfloor void. The failure rate for all remedial measures was found to be 4.0% per annum, but in most cases the problems were noticed by the householder and corrected. The frequency of failures which were not noticed until a remeasurement was carried out was 0.4% per annum. (Author).

  19. Radon concentration in houses over a closed Hungarian uranium mine

    Energy Technology Data Exchange (ETDEWEB)

    Somlai, Janos; Kovacs, Tibor [University of Veszprem Department of Radiochemistry, H-8200, Veszprem P.O.B.: 158 (Hungary); Gorjanacz, Zoran [Mecsek Ore Environmental Protection Co. H-7614, Pecs, P.O.B.: 121 (Hungary); Varhegyi, Andras [Mecsek-OEko Environmental Protection Co. H-7614, Pecs, P.O.B.: 121 (Hungary)

    2006-08-31

    High radon concentration (average 410 kBq m{sup -3}) has been measured in a tunnel of a uranium mine, located 15-55 m below the village of Kovagoszolos, Hungary. The mine was closed in 1997; the artificial ventilation of the tunnel was then terminated and recultivation works begun. In this paper, a study has been made as to whether the tunnel has an influence on the radon concentration of surface dwellings over the mining tunnel. At different distances from the surface projection of the mining tunnel, radon concentration, the gamma dose, radon exhalation and radon concentration of soil gas were measured. The average radon concentration in the dwellings was 483 Bq m{sup -3}. Significantly higher radon concentrations (average 667 Bq m{sup -3}) were measured in houses within +/-150 m from the surface projection of the mining tunnel +50 m, compared with the houses further than the 300-m belt (average 291 Bq m{sup -3}). The average radon concentration of the soil gas was 88.8 kBq m{sup -3}, the average radon exhalation was 71.4 Bq m{sup -2} s{sup -1} and higher values were measured over the passage as well. Frequent fissures crossing the passage and running up to the surface and the high radon concentration generated in the passage (average 410 kBq m{sup -3}) may influence the radon concentration of the houses over the mining tunnel. (author)

  20. Radon measurements in soil and water and its relation with geology, Garhwal Himalaya, India

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M. [Wadia Institute of Himalayan Geology, Dehra Dun (India)

    1998-12-31

    Radon concentrations were measured in soil and spring water in the Garhwal Himalaya using radon emanometer. The measurements were made in the Berinag, Bhatwari and Munsiari Formations. The main rock types in the area are sheared granitic gneiss, porphyritic gneiss, chlorite schist, mica schist, mylonite, slate, phyllite, quartzite and metabasic. The radon concentrations were found to vary from 1.2 kBq/m{sup 3} to 56.5 kBq/m{sup 3} in soil and 0.4 Bq/l to 887 Bq/l in water. The results suggest that the radon emanation is controlled not only by uranium content of the rock and soil but also by structural zones (thrust, fault, etc.) which help in the easy migration of radon from the deeper parts of the earth crust. (author)

  1. Indoor radon measurements and radon prognosis for the province of Kymi, southeastern Finland; Huoneilman radonmittaukset Kymen laeaenissae: Tilannekatsaus ja radonennuste

    Energy Technology Data Exchange (ETDEWEB)

    Pennanen, M.; Maekelaeinen, I.; Voutilainen, A.

    1996-12-01

    The purpose of the regional radon prognosis is to classify areas with different levels of radon risk. The radon prognosis gives the percentages of future homes expected to have indoor radon concentrations exceeding the levels of 200 and 400 Bq/m{sup 3}. It is assumed that no protection against the entry of radon is used in construction. In this study about 5900 indoor radon measurements made in single family houses, semi-detached houses and row houses were used. Data on the location, geology and construction of buildings were determined from maps and questionnaires. An empirical statistical model, the adjusted indoor radon measurements and geological data were used to assess the radon risk from soil and bedrock in different areas. The building sites of the province of Kymi were divided into thirteen sub-areas. The radon prognosis are calculated for the most radon-prone foundation types including (1) houses with a slab-on-grade and (2) houses with a basement or hillside houses with open stairwells between basement and first floor. The radon levels are generally greater in the western part of the area. The radon risk is highest in gravel-dominated esker areas in southwestern, western (in Pyhtaa, Kotka, Anjalankoski, litti, Valkeala) and central (Taipalsaari) parts of the area. The radon risk is also high in some bedrock and till areas, also in southwestern and western parts of the area. In these areas the level of 200 Bq/m{sup 3} will be exceeded in 80 % of new houses. About half of the future houses in these areas will have indoor radon concentrations exceeding 400 Bq/m{sup 3}. The radon risk is lowest in the eastern part of the province of Kymi in every soil type. In this area the level of 200 Bq/m{sup 3} will be exceeded in 30 % of new houses. Below 10 % will exceed 400 Bq/m{sup 3}. (orig.) (14 refs.).

  2. Development of a low-level radon reference atmosphere.

    Science.gov (United States)

    Linzmaier, Diana; Röttger, Annette

    2013-11-01

    In order to calibrate measurement devices for the activity concentration of Rn-222 (radon) in air below 1,000 Bq/m(3), a constant for long time (>5d), homogeneous reference atmosphere is created by a certified activity in a certified volume. The PTB developed this reference atmosphere from 150 Bq/m(3) to 2,000 Bq/m(3) based on the precisely known emanation of Rn-222 from a Ra-226 activity standard. This set-up reduces uncertainties and increases the range of traceability for commercial radon measurement devices. Thus, a gap in radon metrology is closed. The new primary standard for reference atmospheres is realised with a combined relative standard uncertainty of 1.1%.

  3. Radon exhalation study of manganese clay residue and usability in brick production.

    Science.gov (United States)

    Kovács, Tibor; Shahrokhi, Amin; Sas, Zoltán; Vigh, Tamás; Somlai, János

    2017-03-01

    The reuse of by-products and residue streams is an important topic due to environmental and financial aspects. Manganese clay is a residue of manganese ore processing and is generated in huge amounts. This residue may contain some radionuclides with elevated concentrations. In this study, the radon emanation features and the massic exhalation rate of the heat-treated manganese clay were determined with regard to brick production. From the manganese mud depository, 20 samples were collected and after homogenization radon exhalation characteristics were determined as a function of firing temperatures from 100 to 750 °C. The major naturally occurring radionuclides (40)K, (226)Ra and (232)Th concentrations were 607 ± 34, 52 ± 6 and 40 ± 5 Bq kg(-1), respectively, comparable with normal clay samples. Similar to our previous studies a strong correlation was found between the internal structure and the radon emanation. The radon emanation coefficient decreased by ∼96% from 0.23 at 100 °C to 0.01 at 750 °C. The massic radon exhalation rate of samples fired at 750 °C reduced by 3% compared to samples fired at 100 °C. In light of the results, reusing of manganese clay as a brick additive is possible without any constraints.

  4. Efficacy of radon remedial measures

    Energy Technology Data Exchange (ETDEWEB)

    Naismith, S. (National Radiological Protection Board, Chilton (United Kingdom))

    1994-04-01

    About 2000 householders in the UK have taken remedial action to reduce high radon levels in their homes. Some 800 of these householders have sought measurements to confirm the effectiveness of the action. Results for 528 such homes are discussed. (author).

  5. Radon in the soil air of Estonia.

    Science.gov (United States)

    Petersell, Valter; Täht-Kok, Krista; Karimov, Mark; Milvek, Heli; Nirgi, Siim; Raha, Margus; Saarik, Krista

    2017-01-01

    Several investigations in Estonia during 1996¬-1999 have shown that permissible level (200 Bq/m(3)) of radon (222Rn) in indoor air is exceeded in 33% of the inspected dwellings. This makes Estonia one of the five countries with highest radon risk in Europe (Fig 1). Due to correlation between the soil radon risk level and radon concentration in houses, small scale radon risk mapping of soil air was carried out (one study point per 70-100 km(2)). It turned out that one-third of Estonian mainland has high radon risk potential, where radon concentration in soil air exceeds safe limit of 50 kBq/m(3). In order to estimate radon content in soil air, two different methods developed in Sweden were used simultaneously. Besides measuring radon content from soil air at the depth of 80 cm with an emanometer (RnM), maximum potential content of radon in soil (RnG) was estimated based on the rate of eU (226Ra) concentration in soil, which was acquired by using gamma-ray spectrometer. Mapping and following studies revealed that simultaneously measured RnG and RnM in study points may often differ. To inspect the cause, several monitoring points were set up in places with different geological conditions. It appeared that unlike the RnG content, which remains close to average level in repeated measurements, the RnM content may differ more than three times periodically. After continuous observations it turned out that concentration of directly measured radon depended on various factors being mostly controlled by mineral composition of soil, properties of topsoil as well as different factors influencing aeration of soil. The results of Rn monitoring show that reliable level of radon risk in Estonian soils can only be acquired by using calculated Rn-concentration in soil air based on eU content and directly measured radon content of soil air in combination with interpreting specific geological and geochemical situations in the study points. Copyright © 2016 Elsevier Ltd. All rights

  6. A methodology for assessing the maximum expected radon flux from soils in northern Latium (central Italy).

    Science.gov (United States)

    Voltaggio, Mario; Masi, Umberto; Spadoni, Massimo; Zampetti, Giorgio

    2006-12-01

    Northern Latium (Italy) is an area where the Rn risk rate is potentially high because of the extensive outcropping of Neogene U-rich volcanics and the presence of major active tectonic lineaments. The lack of data on Rn risk rates in that area, which is undergoing major urban and industrial development, has prompted this study. It proposes a methodology to evaluate the maximum potential diffusive Rn flux from soils based on the measurement of (226)Ra, (232)Th and (40)K activities by gamma-ray spectrometry, and the measurement of main soil parameters influencing the Rn emanation. This methodology provides a simple, reliable and low-cost tool for drawing up radon flux maps useful to both public planners and private individuals, who want to operate safely in the study area. The proposed methodology may also be applied to other geographic areas outside the prescribed study area.

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

    Science.gov (United States)

    Appleton, J D; Miles, J C H; Green, B M R; Larmour, R

    2008-10-01

    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.

  8. Consumer's Guide to Radon Reduction

    Science.gov (United States)

    ... Radon Share Facebook Twitter Google+ Pinterest Contact Us Consumer's Guide to Radon Reduction: How to Fix Your ... See EPA’s About PDF page to learn more. Consumer's Guide to Radon Reduction: How to Fix Your ...

  9. Seasonal and daily variation of radon at 10 m depth in borehole, Garhwal Lesser Himalaya, India.

    Science.gov (United States)

    Choubey, V M; Arora, B R; Barbosa, S M; Kumar, Naresh; Kamra, Leena

    2011-07-01

    Mostly accepted and widely reported radon (Rn(222)) measurements, a tool for earthquake precursor research, is a part of multi-parametric geophysical observation in the Garhwal Lesser Himalaya for earthquake related studies. Radon is being recorded continuously at an interval of 15 min at 10 m depth in a 68 m deep borehole. Three years high resolution 15 min data at 10 m depth shows a complex trend and has a strong seasonal effect along with some diurnal, semi-diurnal and multi-day recurring trends. A well-defined seasonal pattern is prominent with a high emanation in summer and low values in winter accounting for about a 30% decrease in count values in winter when the atmospheric temperature is very low at this station located 1.90 km above mean sea level. Diurnal, semi-diurnal and multi-day trends in this time-series are mainly observed during April-May and October-November. This is the period of spring and autumn when there is a high contrast in day-night atmospheric temperature. Hence the high fluctuation in Rn concentration is mainly caused by the temperature contrast between the air-column inside the borehole and the atmosphere above the earth's surface.

  10. Seasonal and daily variation of radon at 10 m depth in borehole, Garhwal Lesser Himalaya, India

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M., E-mail: vchoubey@wihg.res.i [Wadia Institute of Himalayan Geology, 33, General Mahadeo Singh Road, Dehradun-248001 (India); Arora, B.R. [Wadia Institute of Himalayan Geology, 33, General Mahadeo Singh Road, Dehradun-248001 (India); Barbosa, S.M. [University of Lisbon, IDL, Campo Grande, Edificio C8, 1749-016 Lisboa (Portugal); Kumar, Naresh; Kamra, Leena [Wadia Institute of Himalayan Geology, 33, General Mahadeo Singh Road, Dehradun-248001 (India)

    2011-07-15

    Mostly accepted and widely reported radon (Rn{sup 222}) measurements, a tool for earthquake precursor research, is a part of multi-parametric geophysical observation in the Garhwal Lesser Himalaya for earthquake related studies. Radon is being recorded continuously at an interval of 15 min at 10 m depth in a 68 m deep borehole. Three years high resolution 15 min data at 10 m depth shows a complex trend and has a strong seasonal effect along with some diurnal, semi-diurnal and multi-day recurring trends. A well-defined seasonal pattern is prominent with a high emanation in summer and low values in winter accounting for about a 30% decrease in count values in winter when the atmospheric temperature is very low at this station located 1.90 km above mean sea level. Diurnal, semi-diurnal and multi-day trends in this time-series are mainly observed during April-May and October-November. This is the period of spring and autumn when there is a high contrast in day-night atmospheric temperature. Hence the high fluctuation in Rn concentration is mainly caused by the temperature contrast between the air-column inside the borehole and the atmosphere above the earth's surface.

  11. Observations of surface radon in Central Italy

    Science.gov (United States)

    Carlo, Piero Di; Pitari, Giovanni; de Luca, Natalia; Battisti, Domenico

    2009-07-01

    Two years of in situ radon concentration measurements in the atmospheric surface layer have been collected in a central Italy town (L’Aquila), located in the Aterno river valley. These data have been analyzed in order to study the controlling mechanisms of surface radon abundance; observations of coincident meteorological parameters confirmed the role of dynamics on the local removal rate of this tracer. The relatively high negative correlation of hourly data of surface wind speed and radon activity concentration ( R = -0.54, on annual scale) suggests that dynamical removal of radon is one of the most important controlling processes of the tracer accumulation in the atmospheric surface layer. An attempt is made to quantify the precipitation impact on radon soil fluxes. No anticorrelation of radon and precipitation comes out from the data ( R = -0.15), as in previous studies. However, since the main physical parameter affecting the ground radon release is expected to be the soil accumulation of water, snow or ice, the emission flux has also been correlated with soil moisture; in this way a much clearer anticorrelation is found ( R = -0.54).

  12. Soil gas radon mapping of Muzaffarabad city, Pakistan

    Directory of Open Access Journals (Sweden)

    Tareen Aleem Dad Khan

    2016-01-01

    Full Text Available Soil-based radon investigations are of value in correlating radon production and its transportation into buildings through the processes of convection and diffusion. Such studies can help in identifying land areas that pose special concerns. We present preliminary results of soil radon gas measurements at 60 different locations in an attempt to map out the geohazard zone of the city of Muzaffarabad. The seismic geohazard microzonation for the area includes five microzones based on different hazard parameters: a very high hazard zone, a high hazard zone, a moderate hazard zone, a low hazard zone, and a safe zone. Measurements were taken with an active radon monitoring system at the depths of 30, 40, 50, and 60 cm below the ground surface. The results obtained were explained by the lithology of the area. Average soil radon gas concentrations were correlated with the depth from the ground surface and indoor radon values for the study area. No significant correlation was found between soil radon gas and meteorological parameters, however soil radon gas increases as the depth from the surface of the ground grows. The results showed a linear relation between soil radon concentrations with depth from ground surface (R2 = 0.9577. The minimum soil radon concentration (68.5 Bq/m3 was found at a depth of 30 cm in the very high hazard zone, the maximum value (53.300 Bq/m3 at a depth of 60 cm in the seismically safe zone. Measured soil gas radon concentrations at depths of 30, 40, 50, and 60 cm were mapped for high, moderate, and low radon concentrations. Elevated soil radon gas concentrations were found in the safe zone, otherwise considered to be suitable for any type of construction.

  13. Determination of the radon concentration in soil and ground water and its association with the seismicity; Determinacion de la concentracion del radon en suelo y agua subterranea y su asociacion con la sismicidad

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Segovia, N. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico)

    2003-07-01

    one could observe that the flaw area the one that had values bigger than the radon concentration was. Some variations of the concentration of the radon could be correlated with the meteorological parameters and those characteristic geologic. The anomalies of the values of the concentration of the radon were presented in general during the rainy season. In the coast of the Pacific one observes an intense seismic activity (M>4) in the period of sampling. The concentration of the radon in floor measured in long periods of time didn't respond with picks one to one to the local earthquakes, but it showed a global increase in an area of high seismic activity. The variations of the radon concentration and of the radiation gamma they showed a strong correlation among if. The differences in the composition of the rocks were reflected in you differ so much in the radon emanation like in the levels of radiation gamma in the area studied. The fluctuations of the concentration of the radon in floor showed occasionally dependence with the meteorological parameters, the same as in the area of the Gulf, the maximum values were obtained mainly in the rainy season. (Author)

  14. Comparison of radon levels in building basements and above- ground floors

    Energy Technology Data Exchange (ETDEWEB)

    Cazula, C.; Campos, M.; Mazzilli, B. [IPEN/CNEN-SP, Sao Paulo (Brazil)

    2014-07-01

    Radon-222, a decay product of Ra-226, is a natural radioactive noble gas that can be found in soil, water and air. Radon and its short-lived decay products in the atmosphere are the most important contributors to human exposure from natural sources. Radon is recognized as the second most significant risk for lung cancer after tobacco smoking. The World Health Organization established a concentration of 100 Bq m{sup -3} for radon in air, in order to limit its hazards. The main source of radon exposition indoors comes from Ra-226, a decay product of the U-238 natural series, present in rocks and soils underneath the building and, to a lesser extent, in the building materials. The dynamics of radon production in rocks and soil and its subsequent indoors emanation is quite complex. It is controlled by factors such as soil permeability and water content, meteorological variability, building foundation characteristics and the usual positive differential pressure between the soil and the indoor environment. This is normally sufficient to bring soil gas from the ground into the building. Radon gas can enter a building by several mechanisms, but the most significant ones are diffusion and pressure-driven flow from the ground. Usually, cracks and holes in the floor and walls and gaps around service pipes are the main entrance for the radon gas. Studies indicated that indoor radon concentration present significant variation on the basement, ground floor and upper floors. The aim of this study is to determine the radon levels in building basements and above- ground floors in the city of Sao Paulo. Radon measurements were carried out through the passive method with solid-state nuclear- track detectors (CR-39), because of their simplicity and long-term integrated read-out. The exposure period was, at least, three months, covering one year minimum, in order to determine the seasonal variation of indoor radon concentration. Document available in abstract form only. (authors)

  15. A model to explain simultaneously the {sup 222}Rn and {sup 220}Rn emanation from thin electrodeposited sources

    Energy Technology Data Exchange (ETDEWEB)

    Vargas, M.J.M. Jurado. E-mail: mjv@unex.es

    2000-06-11

    In thin radioactive sources, loss of radon by emanation is a very common phenomenon, especially in sources made by electrodeposition. A quantification of this effect in radium sources can be easily developed by using a simple model that assumes a radon diffusion term in the ingrowth equations. By measuring the corresponding Rn/Ra activity ratio, a constant diffusion factor can be determined which represents the Rn emanation from the whole source. However, this simple model cannot explain simultaneously the {sup 222}Rn and {sup 220}Rn diffusion produced in a thin source, because it gives diffusion factors that are different by many orders of magnitude for these two isotopes, while these values must be fairly close. In this paper, a new model of diffusion is proposed, which includes a linear dependence of the diffusion factor on the depth of Rn nuclides in the source. This new model has been applied to radium electrodeposited sources and allows us to explain satisfactorily both the {sup 220}Rn/{sup 224}Ra and {sup 222}Rn/{sup 226}Ra activity ratios observed in thin sources.

  16. 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.

  17. Radon-Instrumentation; Radon-Instrumentacion

    Energy Technology Data Exchange (ETDEWEB)

    Moreno y Moreno, A. [Departamento de Apoyo en Ciencias Aplicadas, Benemerita Universidad Autonoma de Puebla, 4 Sur 104, Centro Historico 72000 Puebla (Mexico)

    2003-07-01

    The presentation of the active and passive methods for radon, their identification and measure, instrumentation and characteristics are the objectives of this work. Active detectors: Active Alpha Cam Continuous Air Monitor, Model 758 of Victoreen, Model CMR-510 Continuous Radon Monitor of the Signature Femto-Tech. Passive detectors: SSNTD track detectors in solids Measurement Using Charcoal Canisters, disk of activated coal deposited in a metallic box Electrets Methodology. (Author)

  18. Probabilistic Assessment of Radon Transport at the Monticello, Utah Uranium Mill Tailings Disposal Site

    Science.gov (United States)

    Arnold, B. W.; Ho, C. K.; Cochran, J. R.; Taira, R. Y.

    2001-12-01

    One objective of the cover design at the Monticello site is attenuation of the radon emanation from the mill tailings to the atmosphere. The landfill cover acts as a diffusion barrier, allowing time for the decay of the relatively short-lived Rn-222 gas during migration through the pore spaces of the cover soil. The conceptual model of radon migration through the landfill cover is one-dimensional upward transport driven by the difference in concentration in the tailings and the atmosphere. The processes affecting transport are molecular diffusion and radioactive decay. Uncertainty in the radon emanation rate from the tailings, as well as uncertainties in the effective diffusion coefficient and moisture content for individual layers in the landfill cover are assessed for both present and future conditions. Transport of radon gas by diffusion is enhanced at higher moisture content because of the reduced air phase volume in the soil under these conditions. In a competing manner, higher moisture content results in a lower effective diffusion coefficient for radon gas. Multiple realizations of the system and simulations of radon transport were performed using the RAECOM and FRAMES computer programs. Results indicate a very low probability of exceeding the regulatory limit of 20 pCi/m2/s under present conditions and a low probability of exceedence for future conditions. Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

  19. U.S. laboratory and field trials of metofluthrin (SumiOne) emanators for reducing mosquito biting outdoors.

    Science.gov (United States)

    Lucas, J R; Shono, Y; Iwasaki, T; Ishiwatari, T; Spero, N; Benzon, G

    2007-03-01

    Metofluthrin (SumiOne is a novel, vapor-active pyrethroid that is highly effective against mosquitoes. Laboratory and field trials were conducted in the United States to evaluate the mosquito repellent activity of metofluthrin-treated paper substrates ("emanators"). Initial studies were conducted to evaluate the field performance of 900-cm(2) paper fan emanators impregnated with 160 mg metofluthrin, where Aedes canadensis was the predominant species. Emanators reduced landing rates on human volunteers by between 85% and 100% compared to untreated controls. Subsequent tests with 4,000-cm(2) paper strip emanators impregnated with 200 mg metofluthrin were conducted in a wind tunnel as a precursor to conducting field trials using human bait and laboratory-reared Aedes aegypti. Paper strips, which were pre-aged in a fume hood to determine duration of protection, gave 89-91% reductions in landing rates compared with controls. Similar reductions in biting activity were also noted. Following these tests, field trials to assess effect on landing rates were conducted with emanators positioned 1.22 m on either side of volunteers protected from biting by Tyvek suits, with pre- and posttreatment counts being made. In Florida (predominantly Ochlerotatus spp.) 91-95% reductions were noted 10-30 min after emanators were deployed, while in Washington State (mostly Aedes vexans) 95-97% reductions were observed. These results demonstrate that metofluthrin-treated emanators are highly effective at repelling mosquitoes.

  20. Uranium distribution and radon exhalation from Brazilian dimension stones

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, P.G.Q.; Galembeck, T.M.B. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Bonotto, D.M., E-mail: danielbonotto@yahoo.com.br [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Artur, A.C. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)

    2012-04-15

    This paper provides evaluations of the radiometric behavior and exhalation patterns of radon gas in decorative and dimension stones explored in the Brazilian states of Minas Gerais and Espirito Santo, given the importance of determining radon gas concentrations in human-inhabited environments. A total of 10 silicate rock types were studied, featuring different petrographic/petrophysical characteristics given by seven magmatic rocks (three of which are granitic pegmatites) and three metamorphic rocks. The study, comprising radiometric data of U and monitoring of {sup 222}Rn gas exhalation, shows a strong correlation between petrographic parameters and the physical properties of rocks. U levels ranged between 2.9 and 37 ppm, revealing a good coherence between the presence and the absence of radioactive element-bearing accessory minerals for each rock type. The rate of radon exhalation from the stones is related to the petrographic/petrophysical features of each material. By comparing the {sup 222}Rn level generated by a rock to the amount effectively emanated by it, the rate of emanated gas proves to be insignificant; also, a rock that produces more Rn will not always emanate more. Simulations performed to estimate the radon levels inside residences or any given indoor environment showed that nine samples attained values below the 4 pCi/L EPA limit, whereas one was above that limit. - Highlights: Black-Right-Pointing-Pointer Integration of distinct radiometric data acquired in dimension stones. Black-Right-Pointing-Pointer Dimension stones are extensively commercialized abroad. Black-Right-Pointing-Pointer Rn exhalation above the EPA threshold limit of 4 pCi/L.

  1. Radon dosimetry occupational safety in working area of Sanpaolo IMI organization; Individuazione e dosimetria del radon presso i presidi operativi del gruppo Sanpaolo IMI: parte 1

    Energy Technology Data Exchange (ETDEWEB)

    Scielzo, Giuseppe; Bresciani, Sara [ASO Ordine Mauriziano, Torino (Italy); Coggiola, Maurizio [Torino Univ., Torino (Italy). DTP Traumatologia, ortopedia e medicina del lavoro; Magnone, Maurizio; Chiaberto, Enrico [Arpa Piemonte, Torino (Italy)

    2005-05-15

    The Radon 222 is a natural radioactive gas present inside rocks, soil and building materials. Its decay produce ionizing Alpha radiation. The OMS Organization classified the Radon as cancerogenic substance of group 1 at most high cancerogenicity. In Italy the Radon risk is regulated in law 230 and its modifications.

  2. Novel Radon Sub-Slab Suctioning System

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    2013-01-01

    the zone below the ground-floor construction. For this purpose a new system of prefabricated lightweight elements is introduced. The effectiveness of the system is demonstrated for the case of a ground-floor reinforced concrete slab situated on top of a rigid insulation layer (consisting of a thermal......A new principle for radon protection is currently presented which makes use of a system of horizontal pressurised air ducts located within the lower part of the rigid insulation layer of the ground-floor slab. The function of this system is based on the principles of pressure reduction within...... a grid of horizontal air ducts with low pressure which are able to remove air and radon from the ground. Results showed the system to be effective in preventing radon infiltrating from the ground through the ground-floor slab, avoiding high concentrations of radon being accumulated inside houses...

  3. Distribution of indoor radon levels in Mexico

    CERN Document Server

    Espinosa, G; Rickards, J; Gammage, R B

    1999-01-01

    Our laboratory has carried out a systematic monitoring and evaluation of indoor radon concentration levels in Mexico for ten years. The results of the distribution of indoor radon levels for practically the entire country are presented, together with information on geological characteristics, population density, socioeconomic levels of the population, and architectural styles of housing. The measurements of the radon levels were made using the passive method of nuclear tracks in solids with the end-cup system. CR-39 was used as the detector material in combination with a one-step chemical etching procedure and an automatic digital- image counting system. Wherever a high level was measured, a confirming measurement was made using a dynamic method. The results are important for future health studies, including the eventual establishment of patterns for indoor radon concentration, as it has been done in the USA and Europe.

  4. Radium activity and radon exhalation rates from phosphate ores using CR-39 on-line with an electronic radon gas analyzer 'Alpha GUARD'

    Energy Technology Data Exchange (ETDEWEB)

    Saad, A.F. [Physics Department, Faculty of Science, Zagazig University, Zagazig (Egypt)], E-mail: abdallahsaad@hotmail.com

    2008-08-15

    Nuclear track detectors (NTDs) have seen a major expansion in application to general physical and geological problems reflecting its advances in understanding the exhalation dependence of radon as well as radon and radium concentration distributions in the earth's crust. However, considerable uncertainties still persist, in particular, concerning the detection efficiency of track detectors which are not calibrated precisely to a standard method or an active detector of a unique efficiency. In this investigation, CR-39 NTDs and an electronic radon gas analyzer 'Alpha GUARD' were used for the measurement of radon exhalation rate and radium concentration in phosphate samples collected from two different mines of El-Sobaeya and El-Suez, Egypt. The phosphate sample was loaded into an emanation container (Genitron Instruments GmbH) equipped with a PC-based radon gas analyzer. The CR-39 track detectors were mounted inside a diffusion cup used simultaneously with the Alpha GUARD radon gas analyzer. Radium activity in phosphate samples was found to vary from 1.8 to 361.3kBqkg{sup -1}. The radon exhalation rates in these samples were found to vary from 0.020 (0.003) to 4.125Bqm{sup -2}h{sup -1}(0.658Bqkg{sup -1}h{sup -1})

  5. On the influence of environmental factors on radon levels in caves of Ribeira valley state parks, SP and evaluation of radioactive equilibrium and equilibrium factor between radon and its progeny; Sobre a influencia de fatores ambientais nos niveis de radonio em cavernas dos parques estaduais do vale do Ribeira, SP e avaliacao do equilibrio radioativo e fator de equilibrio entre radonio e seus descendentes

    Energy Technology Data Exchange (ETDEWEB)

    Alberigi, Simone

    2011-07-01

    In the present study it was carried out the monitoring of radon in caves distributed among three state parks of Sao Paulo. The radon concentration were determinate in Morro Preto and Santana caves, located at PETAR - Parque Estadual Turistico do Alto Ribeira (High Ribeira River Tourist State Park), Diabo cave, situated in PEJ - Parque Estadual de Jacupiranga (Jacupiranga State Park) and Colorida cave located in PEI - Parque Estadual Intervales (Intervales State Park PEI). The monitoring covered measurements between April 2009 and June 2010. Radon concentrations were carried out by using the technique of passive detection with CR-39 solid state nuclear track detectors and NRPB diffusion chambers. The detectors were exposed in periods ranging from 30 to 150 days. Radon concentrations varied from 132 Bq/m{sup 3} to 9456 Bq/m{sup 3}. The values of radon concentrations were analyzed together with information about rainfall and internal and external temperature values of the Santana cave environment and regional literature values for a possible relationship between radon variations and weather information. Both the determinations of {sup 22}'6Ra in water samples collected in some caves and rivers and radon emanation from a stalactite collected at Santana cave allowed to verify that the radon in the caves comes from the walls rocks. The verification of the radioactive equilibrium between {sup 222}Rn, {sup 218}Po and '2{sup 14}Po in the exposed detectors was prejudiced by the high tracks densities, committing the methodology effectiveness. The annual effective dose was calculated for three values obtained from the literature for the equilibrium factor. Considering the most realistic scenario, with equilibrium factor of 0.5 and 52 working weeks, the annual effective dose was 5.1 mSv/y. Concerning the worst scenario, which simulates an extreme case, adopting an equilibrium factor equal to 1 and 52 weeks of work per year, the annual effective dose is 10.2 m

  6. LARGE BUILDING RADON MANUAL

    Science.gov (United States)

    The report summarizes information on how bilding systems -- especially the heating, ventilating, and air-conditioning (HVAC) system -- inclurence radon entry into large buildings and can be used to mitigate radon problems. It addresses the fundamentals of large building HVAC syst...

  7. Radon and Cancer

    Science.gov (United States)

    ... exposure and lung cancer: the Iowa Radon Lung Cancer Study. American Journal of Epidemiology 2000; 151(11):1091–1102. [PubMed Abstract] Frumkin H, Samet JM. Radon. CA: A Cancer Journal for Clinicians 2001; 51(6):337–344. [ ...

  8. LARGE BUILDING RADON MANUAL

    Science.gov (United States)

    The report summarizes information on how bilding systems -- especially the heating, ventilating, and air-conditioning (HVAC) system -- inclurence radon entry into large buildings and can be used to mitigate radon problems. It addresses the fundamentals of large building HVAC syst...

  9. Estimation of radon concentration in dwellings in and around Guwahati

    Science.gov (United States)

    Dey, Gautam Kumar; Das, Projit Kumar

    2012-02-01

    It has been established that radon and its airborne decay products can present serious radiation hazards. A long term exposure to high concentration of radon causes lung cancer. Besides, it is also known that out of the total radiation dose received from natural and man-made sources, 60% of the dose is due to radon and its progeny. Taking this into account, an attempt has been made to estimate radon concentration in dwellings in and around Guwahati using aluminium dosimeter cups with CR-39 plastic detectors. Results of preliminary investigation presented in this paper show that the mean concentration is 21.31 Bq m - 3.

  10. Estimation of radon concentration in dwellings in and around Guwahati

    Indian Academy of Sciences (India)

    Gautam Kumar Dey; Projit Kumar Das

    2012-02-01

    It has been established that radon and its airborne decay products can present serious radiation hazards. A long term exposure to high concentration of radon causes lung cancer. Besides, it is also known that out of the total radiation dose received from natural and man-made sources, 60% of the dose is due to radon and its progeny. Taking this into account, an attempt has been made to estimate radon concentration in dwellings in and around Guwahati using aluminium dosimeter cups with CR-39 plastic detectors. Results of preliminary investigation presented in this paper show that the mean concentration is 21.31 Bq m−3.

  11. Soil gas and indoor radon studies in Doon Valley, India

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M.; Sharma, K.K. (Wadia Inst. of Himalayan Geology, Dehra Dun (India)); Ramola, R.C. (Garhwal University, Tehri Garhwal (India). Dept. of Physics)

    1994-02-01

    Radon studies have been carried out in the soil and in dwellings around the Doon Valley, north-west India, using Kodak LR-115 Type II plastic track detectors. Soil gas radon concentrations were found to be higher in carbonaceous shales of the Infra-Krol and in the sandstone of the middle Siwaliks. High values of radon were also observed along prominent tectonic zones, such as the Main Boundary Thrust and the Main Frontal Thrust. In dwellings, the radon values were found to depend on the geology of the area, on the building materials and on the type and construction of the houses. (Author).

  12. Radon exhalation rates and gamma doses from ceramic tiles.

    Science.gov (United States)

    O'Brien, R S; Aral, H; Peggie, J R

    1998-12-01

    This study was carried out to assess the possible radiological hazard resulting from the use of zircon in glaze applied to tiles used in buildings. The 226Ra content of various stains and glazing compounds was measured using gamma spectroscopy and the 222Rn exhalation rates for these materials were measured using adsorption on activated charcoal. The radon exhalation rates were found to be close to or less than the minimum detectable values for the equipment used. This limit was much lower than the estimated exhalation rates, which were calculated assuming that the parameters controlling the emanation and diffusion of 222Rn in the materials studied were similar to those of soil. This implied that the 222Rn emanation coefficients and/or diffusion coefficients for most of the materials studied were very much lower than expected. Measurements on zircon powders showed that the 222Rn emanation coefficient for zircon was much lower than that for soil, indicating that only a small fraction of the 222Rn produced by the decay of 226Ra was able to escape from the zircon grains. The estimated increase in radon concentration in room air and the estimated external gamma radiation dose resulting from the use of zircon glaze are both much lower than the relevant action level and dose limit.

  13. The radon gas. An air pollutant

    Directory of Open Access Journals (Sweden)

    Luis Santiago Quindós Poncela

    2010-12-01

    Full Text Available In this work different aspects about the problem of the radon in dwellings are approached. This gas of natural origin is virtually present in all the soils in the earth’s crust due to the presence of uranium and radium in the composition of them. Depending on architectural factors and of occupancy habits of the house, high concentrations of this gas can be reached indoors. In these situations, there is a quantifiable increment of the risk of developing lung cancer in the inhabitants of the housing. In the last years the methodological improvements in the realization of epidemiologic studies have led to the obtaining of scientific evidences about the relationship between the presence of indoor radon and the risk of lung cancer. This relationship, found years ago in workers of uranium mines, has been corroborated in the case of the residential radon by the light of several recent meta-analysis performed on groups of epidemiologic studies. More than 6.000 radon measurements have been carried out in Spain during the last 25 years. A summary of the results obtained from the main national radon surveys are also presented, as well as the criteria recently established by the Spanish Nuclear Safety Council concerning radon action levels in dwellings and workplaces.

  14. Mutagenicity of radon and radon daughters

    Energy Technology Data Exchange (ETDEWEB)

    Evans, H.H.

    1991-01-01

    The objective of our research is to investigate the dose-response relationship of the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose rate dependence and the nature of the DNA lesion will be studied, using the thymidine kinase and HPRT loci to measure mutation frequency. A deficiency in DNA repair is shown to lead to a greater proportion of mutants with intergenic lesions. The cytotoxic effects of radon and its daughters are similar in human TK6 lymphoblasts and mouse L5178Y lymphoblasts, the cell line used in previous experiments. The results of molecular analysis of four spontaneous and 25 X-radiation induced HPRT{sup {minus}} mutants. Eleven radon-induced HPRT{sup {minus}} mutants have been isolated, and will be analyzed in a similar fashion. 9 figs.

  15. Field fluxes and speciation of arsines emanating from soils.

    Science.gov (United States)

    Mestrot, Adrien; Feldmann, Joerg; Krupp, Eva M; Hossain, Mahmud S; Roman-Ross, Gabriela; Meharg, Andrew A

    2011-03-01

    The biogeochemical cycle of arsenic (As) has been extensively studied over the past decades because As is an environmentally ubiquitous, nonthreshold carcinogen, which is often elevated in drinking water and food. It has been known for over a century that micro-organisms can volatilize inorganic As salts to arsines (arsine AsH(3), mono-, di-, and trimethylarsines, MeAsH(2), Me(2)AsH, and TMAs, respectively), but this part of the As cycle, with the exception of geothermal environs, has been almost entirely neglected because of a lack of suited field measurement approaches. Here, a validated, robust, and low-level field-deployable method employing arsine chemotrapping was used to quantify and qualify arsines emanating from soil surfaces in the field. Up to 240 mg/ha/y arsines was released from low-level polluted paddy soils (11.3 ± 0.9 mg/kg As), primarily as TMAs, whereas arsine flux below method detection limit was measured from a highly contaminated mine spoil (1359 ± 212 mg/kg As), indicating that soil chemistry is vital in understanding this phenomenon. In microcosm studies, we could show that under reducing conditions, induced by organic matter (OM) amendment, a range of soils varied in their properties, from natural upland peats to highly impacted mine-spoils, could all volatilize arsines. Volatilization rates from 0.5 to 70 μg/kg/y were measured, and AsH(3), MeAsH(2), Me(2)AsH, and TMAs were all identified. Addition of methylated oxidated pentavalent As, namely monomethylarsonic acid (MMAA) and dimethylarsinic acid (DMAA), to soil resulted in elevated yearly rates of volatilization with up to 3.5% of the total As volatilized, suggesting that the initial conversion of inorganic As to MMAA limits the rate of arsine and methylarsines production by soils. The nature of OM amendment altered volatilization quantitatively and qualitatively, and total arsines release from soil showed correlation between the quantity of As and the concentration of dissolved organic

  16. Determination of Radon concentration in air using scinti-cell radon monitor

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Taeko [Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst; Morishima, Hiroshige; Arai, Naoki; Shiraishi, Masatoshi; Shigehara, Makiko [Dept. of Nuclear Engineering, School of Science and Technology, Kinki Univ., Higashi-Osaka, Osaka(Japan); Mifune, Masaaki

    2000-01-01

    This study is carried out the methodology characteristics of {sup 222}Rn (Radon) concentration in air using the scinti-cell radon monitor (Trace environmental level detector (PMT-TEL) and Lucas cell (300 A), Pylon Co. and the determination of Radon concentrations in air on Misasa spa area in Tottori pref. and Ikeda spa in Shimane pref. on November 1995 and 1996. We have reached to the following results; (1) Minimum detectable Radon concentrations in air using the scinti-cell monitor are 7.6 Bq/m{sup 3} with 23% of accuracy (relative standard deviation) on the grab sampling of Lucas cell and 0.58 Bq/m{sup 3} with that of 17% on the continuous measuring of PMT-TEL, when it measured after 3.5 hours on the air sampling to determine the mean radon concentrations. The radon concentrations by the PMT-TEL method is about ten times more detectable than those by Lucas cell, that the former is the most sensitive among the detectors used on this research and is able to detect low level environmental concentrations, particularly outdoor and the later is valuable to use conveniently and portably on grab spot sampling of high level radon concentrations indoor air. (2) On the comparison of characteristics on spot monitoring of radon in air, a pico-rad method is suitable for the determination of the mean concentration for continuous sampling period by PMT-TEL and Lucas cell 300 A, and the variation of radon concentration can be observed on elapse of time course. (author)

  17. Radon as geological tracer

    Energy Technology Data Exchange (ETDEWEB)

    Lacerda, T.; Anjos, R.M. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Inst. de Fisica; Valladares, D.L.; Rizzotto, M.; Velasco, H.; Ayub, J. Juri [Universidad Nacional de San Luis (Argentina). Inst. de Matematica Aplicada San Luis (IMASL); Silva, A.A.R. da; Yoshimura, E.M. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

    2012-07-01

    Full text: This work presents measurements of {sup 222}Rn levels performed in La Carolina gold mine and Los Condores tungsten mine at the province of San Luis, Argentina, today used for tourist visitation, and can evaluate the potential use of such radioactive noble gas as tracer or marker for geological processes in underground environments. By concentrations of {sup 40}K, {sup 232}Th and {sup 23}'8U were also measured in the walls of tunnels were determined the rocks mineral composition, what indicated that the mines have the same composition. In this sense, we used nuclear trace plastic detectors CR-39, gamma spectrometry of rock samples and Geiger-Muller (GM) monitors The patterns of radon gas transportation processes revealed that La Carolina could be interpreted through a model based on a radioactive gas confined into a single entrance tube, with constant cross section and air velocity. Los Condores, which has a second main entrance, could be interpreted through a model based on a radioactive gas confined into a two entrance tube, allowing a chimney effect for air circulation. The results showed the high potential of using {sup 222}Rn as a geological tracer. In what concerns the occupational hazard, in summer (time of more intense tourist activity in the mine) La Carolina presented a mean concentration of the radioactive noble gas that exceeds in four times the action level of 1,5 kBq m{sup -3} recommended by the International Commission of Radiological Protection (ICRP). The chimney effect shows the low mean concentration of radon in Los Condores. (author)

  18. EFFECTIVENESS OF RADON CONTROL FEATURES IN NEW HOUSE CONSTRUCTION - SOUTH CENTRAL FLORIDA

    Science.gov (United States)

    The report gives results of a study to evaluate the effectiveness of two slab types (monolithic and slab-in-stem wall) in retarding radon entry in new homes built in accordance with the State of Florida's proposed radon standard for new construction over high radon potential soil...

  19. Monitoring trends in civil engineering and their effect on indoor radon.

    Science.gov (United States)

    Ringer, W

    2014-07-01

    In this paper, the importance of monitoring new building concepts is discussed. The effect of energy-efficient construction technologies on indoor radon is presented in more detail. Comparing the radon levels of about 100 low-energy and passive houses in Austria with radon levels in conventional new houses show that, in energy-efficient new houses, the radon level is about one-third lower than in conventional new houses. Nevertheless, certain features or bad practice may cause high radon levels in energy-efficient new houses. Recommendations to avoid adverse effects were set up. Furthermore, the paper deals with the effect of thermal retrofitting on indoor radon. Results from a Swiss study where 163 dwellings were measured before and after thermal retrofit yield an increase of the radon level of 26% in average. Among the various retrofit measures, replacing windows has the greatest impact on the indoor radon level.

  20. Strategy for the reduction of radon exposure in Norway

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    Elevated indoor radon concentrations are a more extensive problem in Norway than in many other countries. It has been estimated that indoor radon causes approximately 300 deaths from lung cancer each year in Norway. On average, avoiding lung cancer increases life expectancy by 14 to 18 years. Radon is a radioactive noble gas formed continually is a decay product from uranium. Uranium is a natural constituent existing in varying concentrations in bedrock, minerals and soils. For this reason, both the soil air and groundwater contain radon. Radon in buildings normally originates from the soil air in the underlying ground. Indoor air pressure is often low, so that radon-containing air from the surrounding ground gets sucked in through cracks in the building foundations. Elevated indoor radon concentrations can be due to household water drawn from groundwater wells, and radon gas can also be emitted from building materials such as certain types of stone or concrete containing high levels of natural radioactivity. Norway, Sweden and Finland are among the the countries in the world with the highest average indoor radon concentrations. Geological conditions and the cool climate pose a big challenge, but the radon problem can be solved in a cost-effective way. Radon is the most common cause of lung cancer after active smoking. At a radon concentration of 100 Bq/m3, which is not far from the estimated average for Norwegian housing, the risks of dying of radon-induced lung cancer before the age of 75 are 0.1 % for non-smokers and 2 % for smokers, respectively. Many buildings in Norway have radon levels that exceed this. The most important health impact of radon exposure is the increased risk of lung cancer. This increase in risk is assumed to be linear in relation to radon concentration (i.e., the risk is 10 times higher at 1000 Bq/m3 compared to 100 Bq/m3). The risk also increases linearly with exposure time, i.e. there is a tenfold greater risk of contracting lung cancer

  1. Strategy for the reduction of radon exposure in Norway

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    Elevated indoor radon concentrations are a more extensive problem in Norway than in many other countries. It has been estimated that indoor radon causes approximately 300 deaths from lung cancer each year in Norway. On average, avoiding lung cancer increases life expectancy by 14 to 18 years. Radon is a radioactive noble gas formed continually is a decay product from uranium. Uranium is a natural constituent existing in varying concentrations in bedrock, minerals and soils. For this reason, both the soil air and groundwater contain radon. Radon in buildings normally originates from the soil air in the underlying ground. Indoor air pressure is often low, so that radon-containing air from the surrounding ground gets sucked in through cracks in the building foundations. Elevated indoor radon concentrations can be due to household water drawn from groundwater wells, and radon gas can also be emitted from building materials such as certain types of stone or concrete containing high levels of natural radioactivity. Norway, Sweden and Finland are among the the countries in the world with the highest average indoor radon concentrations. Geological conditions and the cool climate pose a big challenge, but the radon problem can be solved in a cost-effective way. Radon is the most common cause of lung cancer after active smoking. At a radon concentration of 100 Bq/m3, which is not far from the estimated average for Norwegian housing, the risks of dying of radon-induced lung cancer before the age of 75 are 0.1 % for non-smokers and 2 % for smokers, respectively. Many buildings in Norway have radon levels that exceed this. The most important health impact of radon exposure is the increased risk of lung cancer. This increase in risk is assumed to be linear in relation to radon concentration (i.e., the risk is 10 times higher at 1000 Bq/m3 compared to 100 Bq/m3). The risk also increases linearly with exposure time, i.e. there is a tenfold greater risk of contracting lung cancer

  2. Indoor radon in Slovenia

    Directory of Open Access Journals (Sweden)

    Vaupotič Janja

    2003-01-01

    Full Text Available The Slovenian Radon Programme started in 1990. Since then, radon and radon short-lived decay products have been surveyed in 730 kindergartens, 890 schools, 1000 randomly selected homes, 5 major spas, 26 major hospitals, 10 major municipal water supply plants, and 8 major wineries. Alpha scintillation cells, etched track detectors, electret-based detectors and various continuously measuring devices have been used. On the basis of estimated effective doses, decisions were made on appropriate mitigation. In total, 35 buildings have been appropriately modified. The programme is displayed and results reviewed chronologically and discussed.

  3. The reliability of radon as seismic precursor

    Science.gov (United States)

    Emilian Toader, Victorin; Moldovan, Iren Adelina; Ionescu, Constantin; Marmureanu, Alexandru

    2016-04-01

    Our multidisciplinary network (AeroSolSys) located in Vrancea (Curvature Carpathian Mountains) includes radon concentration monitoring in five stations. We focus on lithosphere and near surface low atmosphere phenomena using real-time information about seismicity, + / - ions, clouds, solar radiation, temperature (air, ground), humidity, atmospheric pressure, wind speed and direction, telluric currents, variations of the local magnetic field, infrasound, variations of the atmospheric electrostatic field, variations in the earth crust with inclinometers, electromagnetic activity, CO2 concentration, ULF radio wave propagation, seismo-acoustic emission, animal behavior. The main purpose is to inform the authorities about risk situation and update hazard scenarios. The radon concentration monitoring is continuously with 1 hour or 3 hours sample rate in locations near to faults in an active seismic zone characterized by intermediate depth earthquakes. Trigger algorithms include standard deviation, mean and derivative methods. We correlate radon concentration measurements with humidity, temperature and atmospheric pressure from the same equipment. In few stations we have meteorological information, too. Sometime the radon concentration has very high variations (maxim 4535 Bq/m3 from 106 Bq/m3) in short time (1 - 2 days) without being accompanied by an important earthquake. Generally the cause is the high humidity that could be generated by tectonic stress. Correlation with seismicity needs information from minimum 6 month in our case. For 10605 hours, 618 earthquakes with maxim magnitude 4.9 R, we have got radon average 38 Bq/m3 and exposure 408111 Bqh/m3 in one station. In two cases we have correlation between seismicity and radon concentration. In other one we recorded high variation because the location was in an area with multiple faults and a river. Radon can be a seismic precursor but only in a multidisciplinary network. The anomalies for short or long period of

  4. Comparison of seasonal variability in European domestic radon measurements

    Directory of Open Access Journals (Sweden)

    C. J. Groves-Kirkby

    2010-03-01

    Full Text Available Analysis of published data characterising seasonal variability of domestic radon concentrations in Europe and elsewhere shows significant variability between different countries and between regions where regional data is available. Comparison is facilitated by application of the Gini Coefficient methodology to reported seasonal variation data. Overall, radon-rich sedimentary strata, particularly high-porosity limestones, exhibit high seasonal variation, while radon-rich igneous lithologies demonstrate relatively constant, but somewhat higher, radon concentrations. High-variability regions include the Pennines and South Downs in England, Languedoc and Brittany in France, and especially Switzerland. Low-variability high-radon regions include the granite-rich Cornwall/Devon peninsula in England, and Auvergne and Ardennes in France, all components of the Devonian-Carboniferous Hercynian belt.

  5. A Protostellar Jet Emanating from a Hypercompact HII Region

    CERN Document Server

    Guzmán, Andrés E; Rodríguez, Luis F; Contreras, Yanett; Dougados, Catherine; Cabrit, Sylvie

    2016-01-01

    We present radio continuum observations of the high-mass young stellar object (HMYSO) G345.4938+01.4677 made using the Australia Telescope Compact Array (ATCA) at 5, 9, 17, and 19 GHz. These observations provide definite evidence that the outer and inner pairs of radio lobes consist of shock ionized material being excited by an underlying collimated and fast protostellar jet emanating from a hypercompact HII region. By comparing with images taken 6 yr earlier at 5 and 9 GHz using the same telescope, we assess the proper motions of the radio sources. The outer West and East lobes exhibit proper motions of $64\\pm12$ and $48\\pm13$ milliarcsec yr$^{-1}$, indicating velocities projected in the plane of the sky and receding from G345.4938+01.4677 of $520$ and $390$ km s$^{-1}$, respectively. The internal radio lobes also display proper motion signals consistently receding from the HMYSO, with magnitudes of $17\\pm11$ and $35\\pm10$ milliarcsec yr$^{-1}$ for the inner West and East lobes, respectively. The morphology ...

  6. Radon Optical Processing in Radon Space.

    Science.gov (United States)

    1986-06-15

    yields one line through the three-dimensional Fourier transform 1. Radon, J., " Uber die Bestimmung von Funktiontn of the three-dimensional function (3...Alamos, New Mexico , April 11-15. 1983.a 6. W. G. Wee, "Application of projection techniques to image image. Figure 1(a) has approximately 8.0 bits/pixel

  7. Radon exposure in homes: is the contribution of {sup 220}Rn (thoron) to dose always negligible?

    Energy Technology Data Exchange (ETDEWEB)

    Tschiersch, J.; Muesch, M. [GSF-National Research Center for Environment and Health, Inst. of Radiation Protection, Neuherberg (Germany)

    2005-07-01

    {sup 222}Rn (half-life 3.8 d) which emanates from the soil or building material into the indoor air has enough time for diffusion into the room and to become well mixed in the room atmosphere. In contrast, {sup 222}Rn (thoron) which has the short half-life of only 56 s has a lower emanation from soil and may be prevented by simple diffusion barriers on top of the building material to enter the room atmosphere. In general, the effective dose resulting from thoron is estimated to be only about 10% of that of radon (UNSCEAR 2000) and is therefore often not considered in the dose estimates at all. But there are circumstances in which the contribution of thoron to the inhalation dose is much higher. Such a case was investigated at the Loess plateau of Gansu, China, in a pilot study. The dwellings in that area are cut directly into the porous loess or built of adobe on the loess ground. The enhanced emanation from the porous building material and the large emanating surface caused considerably concentrations of thoron and thoron decay products. In 6 different dwellings measurements were performed for 1 day. The mean thoron concentrations ranged 40 - 490 Bq/m{sup 3} (thoron gas) and 0.9 - 13 Bq/m{sup 3} (thoron EEC), whereas the mean radon concentrations ranged 44 - 220 Bq/m{sup 3} (radon gas) and 26 - 190 Bq/m{sup 3} (radon EEC). If we compare the decay product concentration of thoron and radon on the dose relevant basis of the potential alpha-energy concentration (PAEC) (which is expressed in J/m{sup 3}) we have to take into account that the thoron/radon PAEC ratio is higher by a factor of 13.7 than the thoron/radon EEC ratio. This means for our case that the contribution of thoron to the inhalation dose has the same order of magnitude as the contribution of radon. Therefore, thoron should not be neglected in inhalation dose assessments for dwellings with the same exhalation characteristics as the dwellings in this study. (orig.)

  8. Probing the application of Fourier Transform Infrared (FTIR) spectroscopy for assessment of deposited flux of Radon and Thoron progeny in high exposure conditions

    Science.gov (United States)

    Mishra, R.; Sapra, B. K.; Rout, R. P.; Prajith, R.

    2016-12-01

    Direct measurement of Radon and Thoron progeny in the atmosphere and occupational environments such as Uranium mines, Uranium and Thorium handling facilities has gained importance because of its radiological significance in inhalation dose assessment. In this regard, Radon and Thoron Progeny sensors (DTPS and DRPS) are the only passive solid state nuclear track detector (SSNTD, LR115) based devices which are being extensively used for time integrated direct progeny measurements. An essential component of the analysis is the chemical etching of the detectors, followed by spark counting of tracks and then estimation of the inhalation dose using appropriate calibration factors. Alternatively, the tracks may be counted using image analysis techniques. However, under high exposure conditions, both these methods have inherent limitations and errors arising due to increased frequency of tracks. In the present work, we probe the use of Fourier Transform Infra Red (FTIR) spectroscopy to analyse the deposited fluence of the progeny particulates based on change in transmittance of the nitric group vibrational bands of the LR115. A linear relationship between the transmittance and the deposited fluence was observed, which can be used to estimate the deposited fluence rate and the inhalation dose. This alternative method of analysis will provide a faster and non-destructive technique for inhalation dose assessment, specially for routine large scale measurements.

  9. Inhalation exposures due to radon and thoron ((222)Rn and (220)Rn): Do they differ in high and normal background radiation areas in India?

    Science.gov (United States)

    Mishra, Rosaline; Sapra, B K; Prajith, R; Rout, R P; Jalaluddin, S; Mayya, Y S

    2015-09-01

    In India, High Background Radiation Areas (HBRAs) due to enhanced levels of naturally occurring radionuclides in soil (thorium and, to a lesser extent, uranium), are located along some parts of the coastal tracts viz. the coastal belt of Kerala, Tamilnadu and Odisha. It is conjectured that these deposits will result in higher emissions of radon isotopes ((222)Rn and (220)Rn) and their daughter products as compared to Normal Background Radiation Areas (NBRAs). While the annual external dose rates contributed by gamma radiations in these areas are about 5-10 times higher, the extent of increase in the inhalation dose rates attributable to (222)Rn and (220)Rn and their decay products is not well quantified. Towards this, systematic indoor surveys were conducted wherein simultaneous measurements of time integrated (222)Rn and (220)Rn gas and their decay product concentrations was carried out in around 800 houses in the HBRAs of Kerala and Odisha to estimate the inhalation doses. All gas measurements were carried out using pin-hole cup dosimeters while the progeny measurements were with samplers and systems based on the Direct radon/thoron Progeny sensors (DRPS/DTPS). To corroborate these passive measurements of decay products concentrations, active sampling was also carried out in a few houses. The results of the surveys provide a strong evidence to conclude that the inhalation doses due to (222)Rn and (220)Rn gas and their decay products in these HBRAs are in the same range as observed in the NBRAs in India.

  10. Indoor Radon Measurement in Van

    Science.gov (United States)

    Kam, E.; Osmanlioglu, A. E.; Dogan, I.; Celebi, N.

    2007-04-01

    In this study, indoor radon concentrations obtained from the radon surveys conducted in the Van. Radon monitoring was performed by applying a passive, time-integrating measuring technique. For this purpose, CR-39 nuclear track detectors were installed in dwellings for 2 months. After the monitoring period, detectors were collected. In order to make the alpha tracks visible, chemical etching was applied to the exposed detectors. Nuclear track numbers and the corresponding indoor radon concentrations were determined. Annual effective dose equivalents and the risk probabilities caused by indoor radon inhalation were calculated, and the found results compared with the indoor radon concentrations' data measured in different provinces of Turkey.

  11. ROE Radon Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — The polygon dataset represents predicted indoor radon screening levels in counties across the United States. These data were provided by EPA’s Office of Radiation...

  12. Radon in Schools

    Science.gov (United States)

    ... strategy below. Top of Page Testing and Mitigation Standards for Schools Copies of the following Radon Standards ... control is a critical component of any comprehensive indoor air quality (IAQ) management program, l earn how to manage ...

  13. Radon i danske lejeboliger

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Skytte Clausen, Louise

    I denne undersøgelse kortlægges radonindholdet i indeluften og det undersøges, hvordan indholdet af radon i indeluften er fordelt og spredes i en ejendom, og om det er muligt at pege på en bygningsdel eller en bygningskomponent som en spredningsvej for radon i boliger. Boligerne er lejeboliger og...... ligger i etageejendomme, kæde- og rækkehuse tilhørende bygningstyper opført fra 1850 og frem. De udvalgte ejendomme ligger i områder af landet, hvor der ved tidligere undersøgelser har vist sig at være en stor andel af huse med et højt indhold af radon i indeluften. Koncentrationen af radon er målt over...

  14. MODELNG RADON ENTRY INTO FLORIDA HOUSES WITH CONCRETE SLABS AND CONCRETE-BLOCK STEM WALLS, FLORIDA RADON RESEARCH PROGRAM

    Science.gov (United States)

    The report discusses results of modeling radon entry into a typical Florida house whose interior is slightly depressurized. he model predicts that the total radon entry rate is relatively low unless the soil or backfill permeability or radium content is high. ost of the factors c...

  15. Extremely high radon activity concentration in two adits of the abandoned uranium mine 'Podgórze' in Kowary (Sudety Mts., Poland).

    Science.gov (United States)

    Fijałkowska-Lichwa, Lidia

    2016-12-01

    the public occurred as soon as after spending 1 h inside the workings. The minimum monthly effective radiation dose received by every employee in the tourist adit no. 19 in Kowary was higher than 1/5 (4 mSv) of the annual effective dose allowed by Polish law (20 mSv/year). In the non-tourist adit no. 19, the minimum monthly radiation dose was more than 3 times as high as the allowed value of 4 mSv. Due to the highly disturbing and unfavourable, from a radiological protection point of view, conditions inside the disused uranium mine 'Podgórze' in Kowary, the mine manager decided to increase the efficiency of the designed mechanical ventilation system and launch measurements of radon activity concentration in the workplace. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Geology of radon occurrence around Jari in Parvati Valley, Himachal Pradesh, India

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M. [Wadia Inst. of Himalayan Geology, Dehra Dun (India); Sharma, K.K.; Ramola, R.C. [H.N.B. Garhwal Univ., Tehri Garhwal (India). Dept. of Physics

    1997-02-01

    Soil gas and indoor radon concentrations have been measured around Jari in Parvati Valley, Himachal Pradesh, India, to study their relationship with the local geology. Both soil gas and indoor radon concentrations were found to be higher near structurally controlled uranium mineralization. Indoor radon levels in the houses of the study area are considerably higher than the ICRP recommended value of 200 Bq m{sup -3}. The high indoor radon concentration found may be attributed to the geology of the area. This area needs more detailed investigation as it may be one of the areas of high radon risk in India. (Author).

  17. Radon og boligen

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    Radon er en radioaktiv og sundhedsskadelig luftart, som ved indånding øger risikoen for lungekræft. Der er ingen dokumenteret nedre grænse for, hvornår radon er ufarligt. Derfor anbefales det, at man tilstræber et så lavt radonindhold i indeluften som muligt. Man kan hverken lugte, se, høre eller...... smage radon, så vil du vide, om du har radon i din bolig, må du måle radonindholdet i indeluften. Radon forekommer naturligt i jorden og kan suges ind sammen med jordluft, hvis der inde er et undertryk, og hvis konstruktionerne mod jord er utætte. Jordluft trænger ind gennem revner og utætte samlinger......, fx omkring rør til kloak, vand og varmeforsyning. Koncentrationen af radon i jorden varierer meget fra sted til sted, også lokalt og gennem året. Tidligere undersøgelser har vist, at der kan forekomme høje koncentrationer i Sydgrønland, specielt i området syd for Narsalik ved Paamiut, 61°30’N....

  18. Systematic grid-wise radon concentration measurements and first radon map in Cyprus

    CERN Document Server

    Theodoulou, G; Parpottas, Y; 10.1016/j.radmeas.2012.03.019

    2012-01-01

    A systematic study of the indoor airborne radon concentration in the central part of the Nicosia district was conducted, using high-sensitivity active radon portable detectors of the type "RADIM3A". From a total of 108 measurements in 54 grids of 1 km^2 area each, the overall mean value is 20.6 \\pm 13.2 Bq m^-3 (A.M.\\pm S.D.). That is almost twice less than the corresponding average worldwide value. The radon concentration levels in drinking water were also measured in 24 sites of the residential district, using the high-sensitivity radon detector of the type "RADIM3W". The mean value obtained from these measurements is 243.8 \\pm 224.8 mBq L^-1, which is relatively low compared to the corresponding internationally accepted level. The associated annual effective dose rates to each measurement were also calculated and compared to the corresponding worldwide values. From the geographical coordinates of the measuring sites and the corresponding radon concentration values, the digital radon map of the central part...

  19. Radon measurements with a PIN photodiode

    Energy Technology Data Exchange (ETDEWEB)

    Martin-Martin, A. [Laboratorio de Investigacion en Baja Radiactividad (LIBRA), Edificio I-D, Campus Miguel Delibes, Universidad de Valladolid, Valladolid 47011 (Spain) and Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, Valladolid 47011 (Spain)]. E-mail: alonsomm@libra.uva.es; Gutierrez-Villanueva, J.L. [Laboratorio de Investigacion en Baja Radiactividad (LIBRA), Edificio I-D, Campus Miguel Delibes, Universidad de Valladolid, Valladolid 47011 (Spain); Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, Valladolid 47011 (Spain); Munoz, J.M. [Departamento de Electricidad y Electronica, Universidad de Valladolid, Valladolid 47011 (Spain); Garcia-Talavera, M. [Laboratorio de Investigacion en Baja Radiactividad (LIBRA), Edificio I-D, Campus Miguel Delibes, Universidad de Valladolid, Valladolid 47011 (Spain); Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, Valladolid 47011 (Spain); Adamiec, G. [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, Valladolid 47011 (Spain); Iniguez, M.P. [Departamento de Fisica Teorica, Atomica y Optica, Universidad de Valladolid, Valladolid 47011 (Spain)

    2006-10-15

    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 {sup 218}Po and {sup 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.

  20. AlphaGUARD, the new reference for continuous radon monitoring in air, soil, gas, water and material; AlphaGUARD, die neue Referenz fuer die kontinuierliche Messung der Radonkonzentration in Luft, Boden, Wasser und Baumaterial

    Energy Technology Data Exchange (ETDEWEB)

    Roessler, F.; Buerkin, W. [Saphymo GmbH, Frankfurt am Main (Germany); Villert, J. [Bertin Technologies, Montigny (France)

    2016-07-01

    The company Saphymo GmbH has more than 25 years of experience in the field of radon measurement. More than 20 years ago Saphymo developed the professional and robust radon monitor AlphaGUARD, quickly recognized as a standard for reliable and continuous measurements of the radon concentration. Today AlphaGUARD is internationally established as the reference in radon measurement. Following up on this success story the new generation of AlphaGUARD can now be presented. Based on the excellent measurement characteristics of its predecessor the new AlphaGUARD combines the well-proven principle of the pulse ionisation chamber with new and additional features. The robust housing is oriented on the well-proven design of the predecessor and includes now an integrated flow controlled and powerful pump. The instrument can be operated in flow as well as in diffusion mode (without pump). Via the new large display and the intuitive menu navigation all measurement data can be retrieved. The presentation of time series in charts is possible as well as the parametrisation of the instrument. A wide range of accessories, developed in cooperation with various radon experts of universities and laboratories, enables the user a varied and flexible application of the AlphaGUARD: Measurement of the radon concentration in air (radon, thoron, radon progenies), in water (sampling and time resolved measurements) and in soil (soil gas measurements, exhalation measurements), emanation measurements from material, multi spot measurement, online measurement with remote data transmission via Ethernet/DSL, Bluetooth, Wi-Fi, GPRS/3G or satellite. Due to its high sensitivity and its fast and linear response over a large measuring range the AlphaGUARD is excellently suited for calibration laboratories. Furthermore the AlphaGUARD enables ideal prerequisites for field applications: robust housing for operations under harsh conditions, long battery life for the measurement at any location, low

  1. A new method specifically designed to expose cells isolated in vitro to radon and its decay products.

    Science.gov (United States)

    Petitot, F; Morlier, J P; Debroche, M; Pineau, J F; Chevillard, S

    2002-06-01

    A system was set up to provide direct exposure of cells cultured in vitro to radon and its decay products. Radon gas emanating from a uranium source was introduced at a measured concentration in a closed 10-m(3) exposure chamber. Cells were cultured on the microporous membrane of an insert that was floating over the culture medium in a six-well cluster plate. Plates with cells were placed in an open thermoregulated bath within the chamber. Under these conditions, cells were irradiated by direct deposition of radon and radon decay products. During exposure, all parameters, including radon gas concentrations, decay product activities, and potential alpha-particle energy concentrations, were determined by periodic air-grab samplings inside the chamber. The energy spectrum of deposited decay products was characterized. An estimation of alpha-particle flux density on the area containing cells was performed using CR-39 detector films that were exposed in cell-free wells during the cell exposure. The number of alpha-particle traversals per cell was deduced both from the mean number of CR-39 tracks per surface unit and from measurements of entire cells or nuclear surfaces. This paper describes the design of experiment, the dosimetry of radon and radon decay product, and the procedures for aerosol measurements. Our preliminary data show the usefulness of the in vitro cell culture approach to the study of the early cellular effects of radon and its decay products.

  2. Precursory signatures in the radon and geohydrological borehole data for M4.9 Kharsali earthquake of Garhwal Himalaya

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M., E-mail: vchoubey@wihg.res.in [Wadia Institute of Himalayan Geology, 33 General Mahadeo Singh Road, Dehradun 248001 (India); Kumar, Naresh; Arora, B.R. [Wadia Institute of Himalayan Geology, 33 General Mahadeo Singh Road, Dehradun 248001 (India)

    2009-11-01

    Continuous recording of different geophysical parameters incorporated at a single location as a unified effort for earthquake precursory through geodynamical changes initiated for the first time in the Garhwal Himalaya, India. A 68 m deep borehole, penetrating into the water table is operated for continuous radon monitoring along with meteorological/geohydrological observations at two points, one at 10 m (in the air column) and the second one at 50 m (within water column) depths from surface. Preliminary studies reveal diagnostic short duration anomalies in radon concentration recorded few days before the occurrence of a nearby moderate M4.9 earthquake at Kharsali on the 23rd of July, 2007. For nearly half of the year, radon emanation at 10 m depth in the closed air column showed definite pattern of daily variations that may be due to the influence of tidal forces, meteorological and other geodynamical phenomena. This pattern is totally missing during June and July, 2007 when few anomalies for small durations were observed out of which two are unique. These two anomalies exceed 2{sigma} (standard deviation) from average radon concentration in both positive and negative sides. However, its emanation at 50 m depth (water radon) is almost constant throughout the year 2007 except some disturbances observed to the ending of June and during July. These abnormalities in radon emanation and other parameters in the borehole may be considered precursory to the M4.9 Kharsali earthquake of July 23, 2007 having an epicenter distance of 60 km. The empirical relation used for amount of radon anomaly with the epicenter distance predicts an earthquake of M4.6 and M4.7 with the observed anomaly at 10 m and 50 m observation points respectively after taking a 60 km epicenter distance.

  3. Radon in land use planning; Radon i arealplanlegging

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-11-01

    Radon poses a health risk. Therefore, it is important that the municipality takes into account radon, in land use planning. This Radiation Info provides an overview of what makes an additional radon prone area and what tools are available to assess this. The background is the Planning and Building Act provisions on risk analysis (ROS) and zones. (eb)

  4. Radon as a hydrological indicator

    Energy Technology Data Exchange (ETDEWEB)

    Komae, Takami [National Research Inst. of Agricultural Engineering, Tsukuba, Ibaraki (Japan)

    1997-02-01

    The radon concentration in water is measured by a liquid scintillation method. After the radioactive equilibrium between radon and the daughter nuclides was attained, the radon concentration was determined by the liquid scintillation analyzer. {alpha}-ray from radon, then two {beta}- and two {alpha}-ray from the daughter nuclei group were released, so that 500% of the apparent counting efficiency was obtained. The detector limit is about 0.03 Bq/l, the low value, which corresponds to about 5.4x10{sup -15} ppm. By determining the radon concentration in groundwater, behavior of radon in hydrological process, the groundwater exchange caused by pumping and exchange between river water and groundwater were investigated. The water circulation analysis by means of radon indicator in the environment was shown. By using the large difference of radon concentration between in river water and in groundwater, arrival of injected water to the sampling point of groundwater was detected. (S.Y.)

  5. Temporal relationships between the variations of diffuse gaseous emanations and the explosive activity of some active volcanoes of Costa-Rica, examples at the Arenal, Irazu and at the Rincon de la Vieja; Relations temporelles entre les variations des emanations gazeuses diffuses et l`activite explosive de quelques volcans actifs du Costa-Rica, exemples a l`Arenal, l`Irazu et au Rincon de la Vieja

    Energy Technology Data Exchange (ETDEWEB)

    Baubron, J.C. [BRGM, 45 - Orleans (France); Allard, P. [CEA Centre d`Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere; Fernandez, E. [Obviscori, Heridia (Costa Rica); Hammouya, G. [Observatoire de la Soufriere, IPG-P, le Houelmont, 97 - Gourgeyre (France); Soto, G.J. [ICE, San Jose (Costa Rica)

    1996-12-31

    The surveillance of the temporal evolution of radon and helium concentrations in the carbon dioxide of crater fumaroles and gaseous emanations is performed since 1992 on the Irazu, Arenal, Poas and Rincon de la Vieja volcanoes in Costa-Rica. The {sup 3}He/{sup 4}He ratio is used as an indicator of the deep origin of the volcanic gas while radon is an indicator of the CO{sub 2} flux. Radon measurements performed on the Irazu show a continuous decay of radon concentration in the intra-crater fumaroles with an important increase of the gaseous flux since 1992. On the contrary, the external fumaroles on the NW flank were characterized by an important increase in radon concentration in 1994 with a stable flux. The radon surveillance performed in soils around the volcano has shown an intense increase of the diffuse gaseous flows probably linked to the micro-seismic activity of the volcano. Similar observations are reported for the Rincon de la Vieja volcano and correlated with its eruptive history and its phreatic and phreato-magmatic activity. Short paper. (J.S.).

  6. Methods of radon remediation in Finnish dwellings; Asuntojen radonkorjauksen menetelmaet

    Energy Technology Data Exchange (ETDEWEB)

    Arvela, H.

    1995-12-01

    A study was made of remedial measures taken in dwellings with high indoor radon concentrations and the results obtained. The data regarding the remedial measures taken in 400 dwellings was obtained from a questionnaire study. The mean annual average indoor radon concentration before the remedies was 1.500 Bq/m{sup 3}, the concentration exceeding in nearly every house the action level of 400 Bq/m{sup 3}. After the measures were taken the mean indoor radon concentration was 500 Bq/m{sup 3}. The resulting indoor radon concentration was less than 400 Bq/m{sup 3} in 60 percent of the dwellings. The best results were achieved using sub-slab-suction and radon well. These methods effectively decrease both the flow of radon bearing air from soil into dwellings and the radon concentration of leakage air. Typical reduction rates in radon concentration were 70-95 percent. The action level was achieved in more than 70 percent of the houses. Sealing the entry routes and improvement of the ventilation resulted typically in reduction rates of 10-50 percent. The goal of the report is to give useful information for the house owners, the do-it-yourself-mitigators, the mitigation firms and the local authorities. The report includes practical guidance, price information and examples of remedial measures. (13 refs., 10 figs., 2 tabs.).

  7. Molecular dynamics simulations of radon accumulation in water and oil

    Energy Technology Data Exchange (ETDEWEB)

    Pafong, Elvira; Drossel, Barbara [Institut fuer Festkoerperphysik, Technische Universitaet Darmstadt (Germany)

    2016-07-01

    Radon is a radioactive gas that can enter the human body from air or from ground water. Radon can accumulate to levels that considerably rise the risk of lung cancer while it is also known as a a treatment of various ailments, most notably rheumatoid arthritis. The accumulation of radon differs between tissues, with particularly high concentrations in fatty cells. In order to understand the mechanisms responsible for the different solubility of radon in water and fat, we perform molecular dynamics simulations of radon gas at ambient conditions in contact with a bulk material consisting either of water or oil. We evaluate the diffusion coefficient of radon in both media as well as the equilibrium concentration. The crucial point here is to understand the hydrophobic interaction between water and radon as compared to the dispersive interaction between radon and oil. Therefore, we artificially vary the water charges (i.e., the hydrophobicity) as well as the parameters of the van-der-Waals interaction.

  8. Least-squares reverse time migration with radon preconditioning

    KAUST Repository

    Dutta, Gaurav

    2016-09-06

    We present a least-squares reverse time migration (LSRTM) method using Radon preconditioning to regularize noisy or severely undersampled data. A high resolution local radon transform is used as a change of basis for the reflectivity and sparseness constraints are applied to the inverted reflectivity in the transform domain. This reflects the prior that for each location of the subsurface the number of geological dips is limited. The forward and the adjoint mapping of the reflectivity to the local Radon domain and back are done through 3D Fourier-based discrete Radon transform operators. The sparseness is enforced by applying weights to the Radon domain components which either vary with the amplitudes of the local dips or are thresholded at given quantiles. Numerical tests on synthetic and field data validate the effectiveness of the proposed approach in producing images with improved SNR and reduced aliasing artifacts when compared with standard RTM or LSRTM.

  9. Detection of earthquake induced radon precursors by Hilbert Huang Transform

    Science.gov (United States)

    Barman, Chiranjib; Ghose, Debasis; Sinha, Bikash; Deb, Argha

    2016-10-01

    Continuous measurement of radon-222 concentration in soil was carried out across duration of one year at a geologically faulted area having high regional heat flow to detect anomalies caused by seismic activities. The data reveals a range of periodicities present in the radon time series. To identify seismic induced radon changes we treat the time series data through various filtering methods to remove inherent periodicities. The Ensemble Empirical Mode Decomposition (EEMD) is deployed to decompose the signal into its characteristic modes. Hilbert Huang Transform (HHT) is applied for the first time on the physically significant modes obtained by EEMD to represent time-energy-frequency of the recorded soil radon time series. After removing the periodic and quasi-periodic constituents from the original time series, the simulated result shows a forceful correlation in recorded radon-222 anomalies with regional and local seismic events.

  10. A theoretical treatment of adsorption of radon gas on charcoal

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ding; Chiang, Hai-Pang; Shiau, Yuo-Hsien; Tse, Wan-Sun [Academia Sinica, Taipei, TW (China). Inst. of Physics; Skrable, K.; Li, Kuang-Pang

    1997-09-01

    The use of an activated charcoal sampler for radon monitoring has become popular in recent years because of its passiveness and low price. Dynamics of adsorption on a passive sampler have been described with theoretical models. However, extrapolation of the measured results of radon on charcoal to the diurnal fluctuations of the ambient radon concentration is often difficult and even misleading because of the oversimplification of these models. A more generalized approach is undertaken by treating the diurnal variations in radon concentrations as poly-exponential functions and by solving for explicit particular solutions of Fick`s equation. The application of these solutions to various practical situations is explored. This includes their use for charcoal sampler calibration. Estimated values of the adsorption coefficients, k, and diffusion constant, D, appear to be agreeable with corresponding reported values. A triple-sampler protocol is also proposed for radon survey in areas of high diurnal fluctuations. (author)

  11. Geologic influence on indoor radon concentrations and gamma radiation levels in Norwegian dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Sundal, Aud Venche

    2003-09-01

    Indoor radon levels in 1618 Norwegian dwellings located in different geological settings were compared with geological information in order to determine potential correlations between geological factors and indoor radon concentrations in Norway and to establish whether geological information is useful in radon risk analysis. In two geographically limited areas, Kinsarvik and Fen, detailed geological and geochemical investigations were carried out in order to explain their elevated natural radiation environment. Significant correlations between geology and indoor radon concentrations in Norway are found when the properties of both the bedrock and the overburden are taken into account. Areas of high radon risk in Norway include 1) exposed bedrock with elevated levels of radium (mainly alum shale and granites) and b) highly permeable unconsolidated sediments derived from all rock types (mainly glaciofluvial and fluvial deposits) and moderately permeable sediments containing radium rich rock fragments (mainly basal till). More than 20 % of Norwegian dwellings located in the high-risk areas can be expected to contain radon levels exceeding 200 Bq/m3. The elevated radon risk related to penneable building grounds is illustrated in Kinsarvik where the highly permeable sediments and the large vadose zone underlying the Huse residential area enable the transport of radon from large volumes into the dwellings resulting in enhanced indoor radon concentrations. Subterranean air flows caused by temperature/pressure differences between soil air and atmospheric air and elevations differences within the Huse area are shown to strongly affect the annual variations in indoor radon concentrations. The marked contrasts in radon risk potential between different types of building grounds are clearly illustrated in the Fen area where outcrops of the radium rich Fen carbonatites represent areas of high radon risk while only low levels of both indoor radon concentrations and indoor gamma

  12. Radiological risk of building materials using homemade airtight radon chamber

    Energy Technology Data Exchange (ETDEWEB)

    Khalid, Norafatin; Majid, Amran Ab.; Yahaya, Redzuwan; Yasir, Muhammad Samudi [Nuclear Science Programme, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2014-02-12

    Soil based building materials known to contain various amounts of natural radionuclide mainly {sup 238}U and {sup 232}Th series and {sup 40}K. In general most individuals spend 80% of their time indoors and the natural radioactivity in building materials is a main source of indoor radiation exposure. The internal exposure due to building materials in dwellings and workplaces is mainly caused by the activity concentrations of short lived {sup 222}Radon and its progenies which arise from the decay of {sup 226}Ra. In this study, the indoor radon concentration emanating from cement brick, red-clay brick, gravel aggregate and Portland cement samples were measured in a homemade airtight radon chamber using continuous radon monitor 1029 model of Sun Nuclear. Radon monitor were left in the chamber for 96 hours with an hour counting time interval. From the result, the indoor radon concentrations for cement brick, red-clay brick, gravel aggregate and Portland cement samples determined were 396 Bq m{sup −3}, 192 Bq m{sup −3}, 176 Bq m{sup −3} and 28 Bq m{sup −3}, respectively. The result indicates that the radon concentration in the studied building materials have more than 100 Bq m{sup −3} i.e. higher than the WHO action level except for Portland cement sample. The calculated annual effective dose for cement brick, red-clay brick, gravel aggregate and Portland cement samples were determined to be 10 mSv y{sup −1}, 4.85 mSv y{sup −1}, 4.44 mSv y{sup −1} and 0.72 mSv y{sup −1}, respectively. This study showed that all the calculated effective doses generated from indoor radon to dwellers or workers were in the range of limit recommended ICRP action levels i.e. 3 - 10 mSv y{sup −1}. As consequences, the radiological risk for the dwellers in terms of fatal lifetime cancer risk per million for cement brick, red-clay brick, gravel aggregate and Portland cement were calculated to be 550, 267, 244 and 40 persons respectively.

  13. STUDY ON RADON CONCENTRATION AT THE WORK PLACES OF MYSURU, BENGALURU AND KOLAR DISTRICTS OF KARNATAKA STATE, SOUTH INDIA.

    Science.gov (United States)

    Ningappa, C; Hamsa, K S; Reddy, K Umesha; Niranjan, R S; Rangaswamy, D R; Sannappa, J

    2016-10-01

    Concentrations of radon, thoron and their progeny inside the working place depend on the activity of radionuclides in the soil, building materials, atmospheric conditions, construction of the building, type of work and ventilation condition. Radon is a radioactive noble gas, and it is emanated from (226)Ra present in earth crest and building material. Based on the type of work, construction of the building and ventilation condition, concentrations of radon, thoron and their progeny have been measured in 60 workplaces at 10 locations of Mysuru, Bengaluru and Kolar districts of Karnataka state using Solid-State Nuclear Track Detector technique. From the study, variations of radon, thoron and their progeny have been observed with the nature of work. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Radon data processing and outputs for the needs of the State Office for Nuclear Safety (according to the Czech Radon Programme

    Directory of Open Access Journals (Sweden)

    I. Barnet

    2005-06-01

    Full Text Available Much of the population living in the Czech Republic is exposed to radiation from natural sources, especially to the radon effect. The aim of geological research defined by the State Office for Nuclear Safety (SONS was to detect areas with estimated high radon concentration in soil gas. A uniform method of measurements and uniform methodology of radon risk category assessment of geological units and a centralized radon database was established. Radon risk classification was based on statistical evaluation of soil gas radon concentration and permeability in investigated geological units. Prognostic radon risk maps in various scales were the main outputs of this research. With the help of GIS tools spatial analyses were found a correlation between soil gas radon values in selected geological units and indoor measurements in dwellings. After verification of the efficiency of track etch detectors placed in dwellings with the help of prognostic maps 75% reliability of these maps was proven. This reliability of analyses induced the SONS to widely use radon risk maps to determine areas with predicted high radon risk category.

  15. Radon Sources and Associated Risk in terms of Exposure and Dose

    Directory of Open Access Journals (Sweden)

    Efstratios Gregory Vogiannis

    2015-01-01

    Full Text Available Radon concern the international scientific community from early 20th century. Initially as radium emanation, almost the second half of the century as severe harmful to human health. Initial brilliant period of use as medicine, followed by a period of intense concern for its health effects. Primary target groups surveyed were miners early in Europe later in U.S. There is now compelling evidence that radon and its progeny can cause lung cancer. Human activities may create or modify pathways increasing indoor radon concentration compared to outdoor background. These pathways can be controlled by preventive and corrective actions. Indoor Radon and its short-lived progeny attached on aerosol particles or free compose an air mixture that carry a significant energy amount (PAEC. Exposure on PAEC and dose delivered reviewed in detail. Special attention was paid to the case of water workers because lack of adequate data. Radon risk assessment and current legislation regulates dose from radon and its progeny, also were reviewed.

  16. Soil features and indoor radon concentration prediction: radon in soil gas, pedology, permeability and 226Ra content.

    Science.gov (United States)

    Lara, E; Rocha, Z; Santos, T O; Rios, F J; Oliveira, A H

    2015-11-01

    This work aims at relating some physicochemical features of soils and their use as a tool for prediction of indoor radon concentrations of the Metropolitan Region of Belo Horizonte (RMBH), Minas Gerais, Brazil. The measurements of soil gas radon concentrations were performed by using an AlphaGUARD monitor. The (226)Ra content analysis was performed by gamma spectrometry (high pure germanium) and permeabilities were performed by using the RADON-JOK permeameter. The GEORP indicator and soil radon index (RI) were also calculated. Approximately 53 % of the Perferric Red Latosols measurement site could be classified as 'high risk' (Swedish criteria). The Litholic Neosols presented the lowest radon concentration mean in soil gas. The Perferric Red Latosols presented significantly high radon concentration mean in soil gas (60.6 ± 8.7 kBq m(-3)), high indoor radon concentration, high RI, (226)Ra content and GEORP. The preliminary results may indicate an influence of iron formations present very close to the Perferric Red Latosols in the retention of uranium minerals.

  17. The radon EDM apparatus

    Science.gov (United States)

    Tardiff, E. R.; Rand, E. T.; Ball, G. C.; Chupp, T. E.; Garnsworthy, A. B.; Garrett, P.; Hayden, M. E.; Kierans, C. A.; Lorenzon, W.; Pearson, M. R.; Schaub, C.; Svensson, C. E.

    2014-01-01

    The observation of a permanent electric dipole moment (EDM) at current experimentally accessible levels would provide clear evidence of physics beyond the Standard Model. EDMs violate CP symmetry, making them a possible route to explaining the size of the observed baryon asymmetry in the universe. The Radon EDM Experiment aims to search for an EDM in radon isotopes whose sensitivity to CP-odd interactions is enhanced by octupole-deformed nuclei. A prototype apparatus currently installed in the ISAC hall at TRIUMF includes a gas handling system to move radon from a collection foil to a measurement cell and auxiliary equipment for polarization diagnostics and validation. The features and capabilities of the apparatus are described and an overview of the experimental design for a gamma-ray-anisotropy based EDM measurement is provided.

  18. Radon: a bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Lepman, S.R.; Boegel, M.L.; Hollowell, C.D.

    1981-01-01

    The Lawrence Berkeley Laboratory, with the support of the Department of Energy, has developed a computerized database to manage research information in the area of building ventilation and indoor air quality. This literature survey contains references pertaining to the physical properties of radon and its daughters, instrumentation for their measurement, health effects, surveys and measurements, and regulatory information. The references in the bibliography are sequenced in alphabetical order and abstracts are included when supplied by the author. The objective of this report is to disseminate the bibliographic references compiled at the laboratory relating to radon research portion of the program. Interested database users are encouraged to contact the laboratory to receive instructions for direct database acess. A flyer describing the database is supplied at the end of the bibliography and a brief overview of the Radon Research porgram is given.

  19. Radon in Dwellings in the Republic of Kalmykia

    Energy Technology Data Exchange (ETDEWEB)

    Aakerblom, Gustav (Aakerblom och Aakerblom HP, Skaerholmen (Sweden)); German, Olga; Soederman, Ann-Louise (Swedish Radiation Safety Authority, Stockholm (Sweden)); Stamat, Ivan; Venkov, Vladimir (Research Inst. of Radiation Hygiene, St. Petersburg (Russian Federation))

    2009-02-15

    concrete footing. The floor is usually made of wooden planks with quite large visible gaps between them, which makes it easy for radon to penetrate into the air of the living space. A 20-30 centimeter high non-ventilated crawl space is quite usual. Ventilation is provided by the gaps around the windows and doors and the natural draught through the holes. The heating stoves are usually placed in the middle of the houses; coal, wood, sheep and cow dung are used as fuel. The gamma radiation from the building materials is approximately 0.1 muSv/h which indicates that they do not contribute to the radon in the indoor air. The water is stored in cisterns outdoors and this means that it can also be excluded as a source of radon in the indoor air. The measurements showed very few extreme radon values, but the mean value is relatively high. In order to prevent high radon levels indoors, the radon risks should always be taken into account when constructing a building and to prevent the penetration of radon gas by laying a sheet of plastic over the ground in the crawl space or by sealing the openings and cracks in the floor. It is important that the local authorities are aware of the radon problems so that they can advise on the health risks and their mitigation

  20. Radon programmes and health marketing.

    Science.gov (United States)

    Fojtikova, Ivana; Rovenska, Katerina

    2011-05-01

    Being aware of negative health effects of radon exposure, many countries aim for the reduction of the radon exposure of their population. The Czech radon programme was commenced >20 y ago. Since then experts have gathered a lot of knowledge, necessary legislation has been enacted, tens of thousands of inhabitants have been offered free measurement and subsidy for the mitigation. Despite the effort, the effectiveness of the radon programme seems to be poor. Newly built houses still exhibit elevated radon concentrations and the number of houses mitigated is very low. Is it possible to enhance the effectivity of radon programme while keeping it on a voluntary basis? One possible way is to employ health marketing that draws together traditional marketing theories and science-based strategies to prevention. The potential of using marketing principles in communication and delivery of radon information will be discussed.

  1. Effects of air exchange property of passive-type radon-thoron discriminative detectors on performance of radon and thoron measurements.

    Science.gov (United States)

    Omori, Y; Janik, M; Sorimachi, A; Ishikawa, T; Tokonami, S

    2012-11-01

    Pairs of diffusion chambers with different air exchange rates are used in a large-scale survey to determine radon and thoron, separately. When they are enclosed in radon-proof bags for keeping after the exposure, since radon does not escape out immediately from the low-diffusion chamber, it leads to further exposure in the bags and disturbs the estimation of radon and thoron concentrations. In this study, the effects of the different air exchange properties of the radon-thoron discriminative detectors with CR-39 chips on the estimations of radon and thoron concentrations were investigated. The commercially available and frequently used detectors, Raduet, are examined in this study. The result shows that radon escapes out in 10 h. When degassing is not enough after the exposure in a calibration experiment or high-background radiation area, the residual radon causes the overestimation of the radon concentration and increase in the uncertainty in the thoron concentration, i.e. a low-performance quality of radon and thoron measurements.

  2. Newton's Metaphysics of Space as God's Emanative Effect

    Science.gov (United States)

    Jacquette, Dale

    2014-09-01

    In several of his writings, Isaac Newton proposed that physical space is God's "emanative effect" or "sensorium," revealing something interesting about the metaphysics underlying his mathematical physics. Newton's conjectures depart from Plato and Aristotle's metaphysics of space and from classical and Cambridge Neoplatonism. Present-day philosophical concepts of supervenience clarify Newton's ideas about space and offer a portrait of Newton not only as a mathematical physicist but an independent-minded rationalist philosopher.

  3. Radon as a natural tracer for underwater cave exploration.

    Science.gov (United States)

    Csondor, Katalin; Erőss, Anita; Horváth, Ákos; Szieberth, Dénes

    2017-07-01

    The Molnár János cave is one of the largest hypogenic caves of the Buda Thermal Karst (Budapest, Hungary) and mainly characterized by water-filled passages. The major outflow point of the waters of the cave system is the Boltív spring, which feeds the artificial Malom Lake. Previous radon measurements in the cave system and in the spring established the highest radon concentration (71 BqL(-1)) in the springwater. According to previous studies, the origin of radon was identified as iron-hydroxide containing biofilms, which form where there is mixing of cold and thermal waters, and these biofilms efficiently adsorb radium from the thermal water component. Since mixing of waters is responsible for the formation of the cave as well, these iron-hydroxide containing biofilms and the consequent high radon concentrations mark the active cave forming zones. Based on previous radon measurements, it is supposed that the active mixing and cave forming zone has to be close to the spring, since the highest radon concentration was measured there. Therefore radon mapping was carried out with the help of divers in order to get a spatial distribution of radon in the cave passages closest to the spring. Based on our measurements, the highest radon activity concentration (84 BqL(-1)) was found in the springwater. Based on the distribution of radon activity concentrations, direct connection was established between the spring and the István-room of the cave, which was verified by an artificial tracer. However, the distribution of radon in the cave passages shows lower concentrations (18-46 BqL(-1)) compared to the spring, therefore an additional deep inflow from hitherto unknown cave passages is assumed, from which waters with high radon content arrive to the spring. These passages are assumed to be in the active cave formation zone. This study proved that radon activity concentration distribution is a useful tool in underwater cave exploration. Copyright © 2016 Elsevier Ltd. All

  4. Indoor Radon Gas Management For Multi-Site Companies: How To Screen For Potentially High-Risk Sites By Studying The Local Geology

    Science.gov (United States)

    Ruggeri, Rudi; Gigliuto, Andrea; Minnei, Tiziana; Savini, Raffaella

    2008-08-01

    In this article, ENSR presents an evaluation tool for Radon gas monitoring programs that companies with large portfolios of properties will find useful in reducing their efforts and expenditures. The World Health Organization (WHO) considers Radon gas the second cause of lung cancer and the first source of natural radiations affecting the human population. In Italy, Legal Decree No. 230 (0/17/95) is the laws that regulate gas Radon concentrations in work places. Hereunder we present the ENSR approach to executing preliminary geologic studies aimed at planning an instrumental monitoring program for companies.

  5. Description of the behavior of an aquifer by using continuous radon monitoring in a thermal spa

    Energy Technology Data Exchange (ETDEWEB)

    Sainz, Carlos, E-mail: sainzc@unican.es; Rábago, Daniel; Fuente, Ismael; Celaya, Santiago; Quindós, Luis Santiago

    2016-02-01

    Radon ({sup 222}Rn) levels in air and water have been analyzed continuously for almost a year in Las Caldas de Besaya thermal spa, north Spain. Radon is a naturally occurring noble gas from the decay of radium ({sup 226}Ra) both constituents of radioactive uranium 238 series. It has been recognized as a lung carcinogen by the World Health Organization (WHO) and International Agency for Research on Cancer (IARC). Furthermore the Royal Decree R.D 1439/2010 of November, 2010 establishes the obligation to study occupational activities where workers and, where appropriate, members of the public are exposed to inhalation of radon in workplaces such as spas. Together with radon measures several physico-chemical parameters were obtained such as pH, redox potential, electrical conductivity and air and water temperature. The devices used for the study of the temporal evolution of radon concentration have been the RTM 2100, the Radon Scout and gamma spectrometry was complementarily used to determine the transfer factor of the silicone tubes in the experimental device. Radon concentrations obtained in water and air of the spa are high, with an average of 660 Bq/l and 2900 Bq/m{sup 3} respectively, where water is the main source of radon in the air. Radiation dose for workers and public was estimated from these levels of radon. The data showed that the thermal processes can control the behavior of radon which can be also influenced by various physical and chemical parameters such as pH and redox potential. - Highlights: • Radon in water is the major source of indoor air radon concentration in thermal facilities. • Radon in water has been used to characterize the origin of water used for treatments in a spa. • Preliminary dose assessment from radon exposure has been performed.

  6. Evaluation of radon-222 concentration in air of workplaces at Curitiba/PR, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Del Claro, Flavia; Correa, Janine N.; Paschuk, Sergei A.; Kappke, Jaqueline; Perna, Allan F.N.; Reque, Marilson, E-mail: flaviadelclaro@gmail.com, E-mail: spaschuk@gmail.com, E-mail: janine_nicolosi@hotmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Denyak, Valeriy, E-mail: denyak@gmail.com [Instituto de Pesquisa Pele Pequeno Principe (IPPP), Curitiba, PR (Brazil); Rocha, Zildete; Santos, Talita O., E-mail: rocha@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    The isotope Rn-222 is a noble gas that is responsible for approximately half of the effective annual dose received by the world population, and has very high probability to induce the lung cancer. The goal of present research is to evaluate the activity concentration of Rn-222 in the air of workplaces at Curitiba, Parana State. Simultaneously there were performed the measurements of Rn-222 emanation from soil and building materials occurred at evaluated workplaces. Indoor measurements of Rn-222 activity were performed using CR-39 detectors. The instant radon detector AlphaGUARD (Saphymo GmbH) was used in the measurements of the average concentrations of Rn-222 in soil gas and building materials. The average concentration of indoor Rn-222 obtained in the measurements of workplaces vary between 36+/-49 Bq/m³ and 164+/-51 Bq/m³. These values are considered within the reference limit of 200 Bq/m³ established by international agencies such as the United Nations Scientific Committee on the Effects of Atomic Radiation and the International Commission on Radiological Protection, but slightly above the limit of 148 Bq/m³ established by the United States Environmental Protection Agency. The measurements involving building materials presented the concentration values of Rn-222 in a range from 427+/-310 Bq/m³ to 2053+/-700 Bq/m³. The Rn-222 concentrations in soil ranged from 31+/-2 kBq/m³ to 35+/-4 kBq/m³ and the average values of Rn-220 are found in a range of 41+/-6 kBq/m³ and 25+/-11 kBq/m³, thus the concentrations of radon gas soil are below the swedish criterion of 50 kBq/m³ that represent the minimum value for high-risk situation. (author)

  7. Radon (222Rn) in ground water of fractured rocks: A diffusion/ion exchange model

    Science.gov (United States)

    Wood, W.W.; Kraemer, T.F.; Shapiro, A.

    2004-01-01

    Ground waters from fractured igneous and high-grade sialic metamorphic rocks frequently have elevated activity of dissolved radon (222Rn). A chemically based model is proposed whereby radium (226Ra) from the decay of uranium (238U) diffuses through the primary porosity of the rock to the water-transmitting fracture where it is sorbed on weathering products. Sorption of 226Ra on the fracture surface maintains an activity gradient in the rock matrix, ensuring a continuous supply of 226Ra to fracture surfaces. As a result of the relatively long half-life of 226Ra (1601 years), significant activity can accumulate on fracture surfaces. The proximity of this sorbed 226Ra to the active ground water flow system allows its decay progeny 222Rn to enter directly into the water. Laboratory analyses of primary porosity and diffusion coefficients of the rock matrix, radon emanation, and ion exchange at fracture surfaces are consistent with the requirements of a diffusion/ion- exchange model. A dipole-brine injection/withdrawal experiment conducted between bedrock boreholes in the high-grade metamorphic and granite rocks at the Hubbard Brook Experimental Forest, Grafton County, New Hampshire, United States (42??56???N, 71??43???W) shows a large activity of 226Ra exchanged from fracture surfaces by a magnesium brine. The 226Ra activity removed by the exchange process is 34 times greater than that of 238U activity. These observations are consistent with the diffusion/ion-exchange model. Elutriate isotopic ratios of 223Ra/226Ra and 238U/226Ra are also consistent with the proposed chemically based diffusion/ion-exchange model.

  8. Unexpected Daily Peaks in a Laboratory Simulation Experiment of Radon Signals

    Science.gov (United States)

    Bezaly, Orr Rose; Steinitz, Gideon; Israelevich, Peter; Kotlarsky, Peter; Piatibratova, Oksana; Malik, Uri; Asperil, Tal; Marco, Shmuel

    2017-04-01

    Radon is a noble radioactive gas of special interest in earth sciences due to both its unique chemical and physical properties and its natural abundance. The most stable isotope of radon, 222Rn, has a half-life of 3.823 days and is the only gas-phase atom in the 238U decay series. Radon could be considered as a possible tracer for tectonic and volcanic processes, yet the physical mechanisms that influence radon emanation from rock and transport are unclear. Our team strives to observe and analyse radon signals in monitored environments. Simulation of radon signals and investigation of their characteristics in laboratory experiments are conducted using radon in an enclosed chamber, termed "Enhanced Confined Mode" (ECM). An ECM experiment will be described; its arrangement comprises of two 222Rn sources of activity ˜105Bq each. The sources are connected in parallel via tube to a horizontal stainless steel cylinder (˜570cm3) that contains air at atmospheric pressure. Direct count rate measurements were performed using a NaI (2x2") gamma-ray scintillation detector aligned along the cylinder's axis, at one minute resolution, for over 60 days. Radon is supplied into the ECM chamber by diffusion and it disintegrates as it undergoes radioactive decay. A priori, a steady state of diffusion and radioactive decay rates is expected. However, our results show evident deviations from this expected steady state, namely fluctuations that are significant relative to the uncertainty in measurements. Predominant daily peaks characterise the data. Signal processing and analysis of these daily peaks will be presented.

  9. Publications about Radon

    Science.gov (United States)

    There is no known safe level of exposure to radon. EPA strongly recommends that you fix your home if your test shows 4 picocuries (pCi/L) or more. These publications and resources will provide you with the information you need to fix your home.

  10. What Is Radon?

    Science.gov (United States)

    ... in both cigarette smoke and radon. In some animals, the risk of certain other cancers was also increased. In lab studies using human ... cancer grow is called a carcinogen .) The American Cancer Society looks to these ... laboratory, animal, and human research studies. Based on animal and ...

  11. The Chemistry of Radon

    Science.gov (United States)

    Avrorin, V. V.; Krasikova, R. N.; Nefedov, V. D.; Toropova, M. A.

    1982-01-01

    We shall review the discovery of this element, studies of its chemical nature, and modern ideas on its chemical and physical properties. Possible chemical and nuclear-chemical methods of synthesising new radon compounds and of determining their properties and their identity will be discussed, using information published up to May 1980. 121 references.

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

    Science.gov (United States)

    Gillmore, G. K.; Jabarivasal, N.

    2010-04-01

    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 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.

  13. 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.

  14. The NIST Primary Radon-222 Measurement System

    OpenAIRE

    Collé, R.; Hutchinson, J. M. R.; Unterweger, M. P.

    1990-01-01

    Within the United States, the national standard for radon measurements is embodied in a primary radon measurement system that has been maintained for over 50 years to accurately measure radon (222Rn) against international and national radium (226Ra) standards. In turn, all of the radon measurements made at the National Institute of Standards and Technology (NIST) and the radon transfer calibration standards and calibration services provided by NIST are directly related to this national radon ...

  15. RESIDENTIAL RADON AND BIRTH DEFECTS: A POPULATION-BASED ASSESSMENT

    Science.gov (United States)

    Langlois, Peter H; Lee, MinJae; Lupo, Philip J; Rahbar, Mohammad H; Cortez, Ruben K

    2015-01-01

    BACKGROUND Associations have been reported between maternal radiation exposure and birth defects. No such studies were found on radon. Our objective was to determine if there is an association between living in areas with higher radon levels and birth defects. METHODS The Texas Birth Defects Registry provided data on all birth defects from 1999–2009 from the entire state. Mean radon levels by geologic region came from the Texas Indoor Radon Survey. The association between radon and birth defects was estimated using multilevel mixed effect Poisson regression. RESULTS Birth defects overall were not associated with residential radon levels. Of the 100 other birth defect groups with at least 500 cases, 14 were significantly elevated in areas with high mean radon level in crude analyses, and 9 after adjustment for confounders. Cleft lip with/without cleft palate had an adjusted prevalence ratio (aPR) of 1.16 per 1 picoCurie/liter (pCi/l) increase in exposure to region mean radon, 95% confidence interval (CI) 1.08, 1.26. Cystic hygroma / lymphangioma had an aPR of 1.22 per 1 pCi/l increase, 95% CI 1.02, 1.46. Other associations were suggested but not as consistent: three skeletal defects, Down syndrome, other specified anomalies of the brain, and other specified anomalies of the bladder and urethra. CONCLUSIONS In the first study of residential radon and birth defects, we found associations with cleft lip w/wo cleft palate and cystic hygroma / lymphangioma. Other associations were suggested. The ecological nature of this study and multiple comparisons suggest that our results be interpreted with caution. PMID:25846606

  16. Radon and lung cancer; Radon et cancer du poumon

    Energy Technology Data Exchange (ETDEWEB)

    Baysson, H; Billon, S.; Catelinois, O.; Gambard, J.P.; Laurier, D.; Rogel, A.; Tirmarche, M

    2004-12-01

    Radon is a natural radioactive gas that tends to accumulate in indoor environments; its concentration is highest in areas with granite sub-soils. Epidemiologic studies of uranium miners and animal data demonstrate the radon inhalation increases the risk of lung cancer. The objective of this paper is to present the available data on the French population's exposure to radon and the current epidemiologic knowledge of its effects, from cohort studies of uranium miners and indoor radon case-control studies.

  17. Mapping of gas radon in soil of the Fresnillo City, Zacatecas; Mapeo de gas radon en suelo de la Ciudad de Fresnillo, Zacatecas

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Q, I. S.; Lopez del R, H.; Davila R, J. I.; Mireles G, F., E-mail: hlopezdelrio@hotmail.com [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2012-10-15

    With the purpose of locating areas with high rates of gas radon exhalation, it has begun to measure the radon flow in soil for residence use in the Fresnillo City, Zacatecas State, Mexico, applying the method of the open vial and liquid scintillation. The gas radon accumulation is made in a camera situated to a depth between 25 and 35 cm. In this work the partial results of the research in course are presented. The values obtained for the radon exhalation have varied of <2.25 up to 14.42 Bq/m{sup 2}{center_dot}h. (Author)

  18. Evaluation of the effect of a cover layer on radon exhalation from uranium mill tailings: transient radon flux analysis.

    Science.gov (United States)

    Ferry, Cécile; Richon, Patrick; Beneito, Alain; Robé, Marie-Christine

    2002-01-01

    An experimental study concerning the transport of 222Rn in uranium mill tailings (UMTs) and in the cover layer was launched in 1997 with the participation of the French uranium mining company (COGEMA). Evaluation of the cover layer's effectiveness in reducing 222Rn flux emanating from UMTs was one of its objectives. In the first phase, the 222Rn flux densities were measured regularly on a UMT layer. In the second phase, the UMT was covered with a one-meter layer of compacted material consisting of crushed waste rock derived from mining activities. Radon-222 flux was then measured at the surface of this cover layer. Observations were compared with radon flux calculated using TRACI, a model for vertical water and gas flow and radon transport. The results show that the calculations bear a fair resemblance to the observations in both cases. They also show that the effectiveness of the cover layer calculated with TRACI, using the thickness and textural properties of the cover material, is very close to the measured effectiveness.

  19. Radon contents in groundwater and the uncertainty related to risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Fukui, Masami [Kyoto Univ. (Japan)

    1997-02-01

    The United States has proposed 11 Bq/l (300 pCi/l) as the maximum contaminant levels (MCLs) of radon. Japan has not set up the standards for drinking water. The problems about evaluation of effects of radon on organism and MCLs of radon in groundwater and drinking water in 12 countries were reported. The local area content the high concentrations of radon, but generally it`s low levels were observed in Nigeria, China and Mexico. The countries which content high concentration of radon were Greek, Slovakia, Bornholm Island and Scotland. There are high and low concentration area in US and Japan. I proposed an uncertainty scheme on risk assessment for the exposure by radon. (S.Y.)

  20. Relationship among cancer,indoor radon and geology from Gejiu area

    Institute of Scientific and Technical Information of China (English)

    卢伟; 王任重; 等

    1996-01-01

    The mortality of lung cancer in Gejiu has reached the peak in the world.The indoor radon levels in Gejiu are measured by SSNTD.The results indicate that a higher indoor radon level widely exists in Gejiu area;the radon level in houses situated in geologic fault zone is 6 times as high as 2km from fault zone;the radon level in soil in faults is 6-8 times as high as 1km from faults;the radon level of the cancer patients' houses is 1.45 times as high as healths'.The relationship between indoor radon level and incidence of lung cancer is given for the firest time.

  1. On the air-filled effective porosity parameter of Rogers and Nielson's (1991) bulk radon diffusion coefficient in unsaturated soils.

    Science.gov (United States)

    Saâdi, Zakaria

    2014-05-01

    The radon exhalation rate at the earth's surface from soil or rock with radium as its source is the main mechanism behind the radon activity concentrations observed in both indoor and outdoor environments. During the last two decades, many subsurface radon transport models have used Rogers and Nielson's formula for modeling the unsaturated soil bulk radon diffusion coefficient. This formula uses an "air-filled effective porosity" to account for radon adsorption and radon dissolution in the groundwater. This formula is reviewed here, and its hypotheses are examined for accuracy in dealing with subsurface radon transport problems. The author shows its limitations by comparing one dimensional steady-state analytical solutions of the two-phase (air/water) transport equation (Fick's law) with Rogers and Nielson's formula. For radon diffusion-dominated transport, the calculated Rogers and Nielson's radon exhalation rate is shown to be unrealistic as it is independent of the values of the radon adsorption and groundwater dissolution coefficients. For convective and diffusive transport, radon exhalation rates calculated using Fick's law and this formula agree only for high values of gas-phase velocity and groundwater saturation. However, these conditions are not usually met in most shallow subsurface environments where radon migration takes place under low gas phase velocities and low water saturation.

  2. Evaluation of radon occurrence in groundwater from 16 geologic units in Pennsylvania, 1986–2015, with application to potential radon exposure from groundwater and indoor air

    Science.gov (United States)

    Gross, Eliza L.

    2017-05-11

    Results from 1,041 groundwater samples collected during 1986‒2015 from 16 geologic units in Pennsylvania, associated with 25 or more groundwater samples with concentrations of radon-222, were evaluated in an effort to identify variations in radon-222 activities or concentrations and to classify potential radon-222 exposure from groundwater and indoor air. Radon-222 is hereafter referred to as “radon.” Radon concentrations in groundwater greater than or equal to the proposed U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) for public-water supply systems of 300 picocuries per liter (pCi/L) were present in about 87 percent of the water samples, whereas concentrations greater than or equal to the proposed alternative MCL (AMCL) for public water-supply systems of 4,000 pCi/L were present in 14 percent. The highest radon concentrations were measured in groundwater from the schists, gneisses, and quartzites of the Piedmont Physiographic Province.In this study, conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Health and the Pennsylvania Department of Environmental Protection, groundwater samples were aggregated among 16 geologic units in Pennsylvania to identify units with high median radon concentrations in groundwater. Graphical plots and statistical tests were used to determine variations in radon concentrations in groundwater and indoor air. Median radon concentrations in groundwater samples and median radon concentrations in indoor air samples within the 16 geologic units were classified according to proposed and recommended regulatory limits to explore potential radon exposure from groundwater and indoor air. All of the geologic units, except for the Allegheny (Pa) and Glenshaw (Pcg) Formations in the Appalachian Plateaus Physiographic Province, had median radon concentrations greater than the proposed EPA MCL of 300 pCi/L, and the Peters Creek Schist (Xpc), which is in the Piedmont

  3. Radon Concentrations in Drinking Water in Beijing City, China and Contribution to Radiation Dose

    Science.gov (United States)

    Wu, Yun-Yun; Ma, Yong-Zhong; Cui, Hong-Xing; Liu, Jian-Xiang; Sun, Ya-Ru; Shang, Bing; Su, Xu

    2014-01-01

    222Rn concentrations in drinking water samples from Beijing City, China, were determined based on a simple method for the continuous monitoring of radon using a radon-in-air monitor coupled to an air-water exchanger. A total of 89 water samples were sampled and analyzed for their 222Rn content. The observed radon levels ranged from detection limit up to 49 Bq/L. The calculated arithmetic and geometric means of radon concentrations in all measured samples were equal to 5.87 and 4.63 Bq/L, respectively. The average annual effective dose from ingestion of radon in drinking water was 2.78 μSv, and that of inhalation of water-borne radon was 28.5 μSv. It is concluded that it is not the ingestion of waterborne radon, but inhalation of the radon escaping from water that is a substantial part of the radiological hazard. Radon in water is a big concern for public health, especially for consumers who directly use well water with very high radon concentration. PMID:25350007

  4. Radon Concentrations in Drinking Water in Beijing City, China and Contribution to Radiation Dose

    Directory of Open Access Journals (Sweden)

    Yun-Yun Wu

    2014-10-01

    Full Text Available 222Rn concentrations in drinking water samples from Beijing City, China, were determined based on a simple method for the continuous monitoring of radon using a radon-in-air monitor coupled to an air-water exchanger. A total of 89 water samples were sampled and analyzed for their 222Rn content. The observed radon levels ranged from detection limit up to 49 Bq/L. The calculated arithmetic and geometric means of radon concentrations in all measured samples were equal to 5.87 and 4.63 Bq/L, respectively. The average annual effective dose from ingestion of radon in drinking water was 2.78 μSv, and that of inhalation of water-borne radon was 28.5 μSv. It is concluded that it is not the ingestion of waterborne radon, but inhalation of the radon escaping from water that is a substantial part of the radiological hazard. Radon in water is a big concern for public health, especially for consumers who directly use well water with very high radon concentration.

  5. Analysis of the Difference of Radon Concentration between Water Treatment Plant and Tap water in house

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jeongil; Yoo, Donghan; Kim, Heereyoung [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2013-05-15

    As importance for the health, measurements and analysis about radon is active recently. Especially, radon concentration measurement about underground water which people drink was been carried out by the environment organizations in Korea and has been hot-issued because of the high radon concentration in water source. In present study, the difference of radon concentration among water source, water treatment plant and tap water in house is analyzed. It makes sense that the radon concentration in water treatment plant can represent the radon concentration in the tap water. Through the above experiments, the difference of the radon concentration between water treatment plant and tap water in house is figured out. It contributes to confirm more specific basis for estimating the annual radon exposure for the public. With further experiments and analysis, it is thought that it will be used as tool to assess more qualitatively for the radon concentration in tap water. Finally, this Fundamental approach will help in making new regulations about radon.

  6. Radon concentrations in drinking water in Beijing City, China and contribution to radiation dose.

    Science.gov (United States)

    Wu, Yun-Yun; Ma, Yong-Zhong; Cui, Hong-Xing; Liu, Jian-Xiang; Sun, Ya-Ru; Shang, Bing; Su, Xu

    2014-10-27

    (222)Rn concentrations in drinking water samples from Beijing City, China, were determined based on a simple method for the continuous monitoring of radon using a radon-in-air monitor coupled to an air-water exchanger. A total of 89 water samples were sampled and analyzed for their (222)Rn content. The observed radon levels ranged from detection limit up to 49 Bq/L. The calculated arithmetic and geometric means of radon concentrations in all measured samples were equal to 5.87 and 4.63 Bq/L, respectively. The average annual effective dose from ingestion of radon in drinking water was 2.78 μSv, and that of inhalation of water-borne radon was 28.5 μSv. It is concluded that it is not the ingestion of waterborne radon, but inhalation of the radon escaping from water that is a substantial part of the radiological hazard. Radon in water is a big concern for public health, especially for consumers who directly use well water with very high radon concentration.

  7. Description of the behavior of an aquifer by using continuous radon monitoring in a thermal spa.

    Science.gov (United States)

    Sainz, Carlos; Rábago, Daniel; Fuente, Ismael; Celaya, Santiago; Quindós, Luis Santiago

    2016-02-01

    Radon ((222)Rn) levels in air and water have been analyzed continuously for almost a year in Las Caldas de Besaya thermal spa, north Spain. Radon is a naturally occurring noble gas from the decay of radium ((226)Ra) both constituents of radioactive uranium 238 series. It has been recognized as a lung carcinogen by the World Health Organization (WHO) and International Agency for Research on Cancer (IARC). Furthermore the Royal Decree R.D 1439/2010 of November, 2010 establishes the obligation to study occupational activities where workers and, where appropriate, members of the public are exposed to inhalation of radon in workplaces such as spas. Together with radon measures several physico-chemical parameters were obtained such as pH, redox potential, electrical conductivity and air and water temperature. The devices used for the study of the temporal evolution of radon concentration have been the RTM 2100, the Radon Scout and gamma spectrometry was complementarily used to determine the transfer factor of the silicone tubes in the experimental device. Radon concentrations obtained in water and air of the spa are high, with an average of 660 Bq/l and 2900 Bq/m(3) respectively, where water is the main source of radon in the air. Radiation dose for workers and public was estimated from these levels of radon. The data showed that the thermal processes can control the behavior of radon which can be also influenced by various physical and chemical parameters such as pH and redox potential.

  8. The use of mapped geology as a predictor of radon potential in Norway.

    Science.gov (United States)

    Watson, Robin J; Smethurst, Mark A; Ganerød, Guri V; Finne, Ingvild; Rudjord, Anne Liv

    2017-01-01

    Radon exposure is considered to cause several hundred fatalities from lung-cancer each year in Norway. A national map identifying areas which are likely to be exposed to elevated radon concentrations would be a useful tool for decision-making authorities, and would be particularly important in areas where only few indoor radon measurements exist. An earlier Norwegian study (Smethurst et al. 2008) produced radon hazard maps by examining the relationship between airborne gamma-ray spectrometry, bedrock and drift geology, and indoor radon. The study was limited to the Oslo region where substantial indoor radon and airborne equivalent uranium datasets were available, and did not attempt to test the statistical significance of relationships, or to quantify the confidence of its predictions. While it can be anticipated that airborne measurements may have useful predictive power for indoor radon, airborne measurement coverage in Norway is at present sparse; to provide national coverage of radon hazard estimates, a good understanding of the relationship between geology and indoor radon is therefore important. In this work we use a new enlarged (n = 34,563) form of the indoor radon dataset with national coverage, and we use it to examine the relationship between geology and indoor radon concentrations. We use this relationship to characterise geological classes by their radon potential, and we produce a national radon hazard map which includes confidence limits on the likelihood of areas having elevated radon concentrations, and which covers the whole of mainland Norway, even areas where little or no indoor radon data are available. We find that bedrock and drift geology classes can account for around 40% of the total observed variation in radon potential. We test geology-based predictions of RP (radon potential) against locally-derived estimates of RP, and produce classification matrices with kappa values in the range 0.37-0.56. Our classifier has high predictive value

  9. (Mutagenicity of radon and radon daughters)

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The current objective of our research is to investigate the dose-response relationship of the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose-rate dependence will be studied, as well as the nature of the DNA lesions. The effect of DNA repair on the lethal and mutagenic effects of exposure and on the character of the DNA lesions will be investigated by comparing the response of L5178Y strains which differ in their ability to rejoin X radiation-induced DNA double-strand breaks. This report discusses progress incurred from 4/1/1988--10/1/1990. 5 refs., 9 figs., 6 tabs.

  10. Measurement of radon concentration in water by means of {alpha}, {gamma} spectrometry. Radon concentration in ground and spring water in Hiroshima Prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Shizuma, Kiyoshi [Hiroshima Univ. (Japan)

    1997-02-01

    Radon ({sup 222}Rn, T{sub 1/2}=3.8235{+-}0.0003d) is {alpha}-ray releasing nuclide, so that it can not be detected by {gamma}-ray measurement. But, the daughter nuclides {sup 214}Pb (T{sub 1/2}=26.8 min) and {sup 214}Bi (T{sub 1/2}=19.9 min) release {gamma}-ray, accordingly they are measured by Ge detector. Their radioactive equilibrium is kept in the closed vessel, because their half-lives are shorter than that of radon. We developed a measurement method of radon concentration by means of {gamma}-spectrometry. We applied this method to catch radon in the atmosphere by active carbon. The same principle can be applied to radon in water. Radon concentrations in the ground water were measured in 22 points in the Higashi-Hiroshima city and 82 points in the Hiroshima prefecture. The efficiencies of {gamma}-ray were determined. The radon concentration showed between 11 and 459 Bq/l and the average was 123 Bq/l. The high concentration of radon was distributed in the spring of granitic layer and higher concentration of radon were observed in the ground water of fault. (S.Y.)

  11. Mapping geogenic radon potential by regression kriging.

    Science.gov (United States)

    Pásztor, László; Szabó, Katalin Zsuzsanna; Szatmári, Gábor; Laborczi, Annamária; Horváth, Ákos

    2016-02-15

    Radon ((222)Rn) gas is produced in the radioactive decay chain of uranium ((238)U) which is an element that is naturally present in soils. Radon is transported mainly by diffusion and convection mechanisms through the soil depending mainly on the physical and meteorological parameters of the soil and can enter and accumulate in buildings. Health risks originating from indoor radon concentration can be attributed to natural factors and is characterized by geogenic radon potential (GRP). Identification of areas with high health risks require spatial modeling, that is, mapping of radon risk. In addition to geology and meteorology, physical soil properties play a significant role in the determination of GRP. In order to compile a reliable GRP map for a model area in Central-Hungary, spatial auxiliary information representing GRP forming environmental factors were taken into account to support the spatial inference of the locally measured GRP values. Since the number of measured sites was limited, efficient spatial prediction methodologies were searched for to construct a reliable map for a larger area. Regression kriging (RK) was applied for the interpolation using spatially exhaustive auxiliary data on soil, geology, topography, land use and climate. RK divides the spatial inference into two parts. Firstly, the deterministic component of the target variable is determined by a regression model. The residuals of the multiple linear regression analysis represent the spatially varying but dependent stochastic component, which are interpolated by kriging. The final map is the sum of the two component predictions. Overall accuracy of the map was tested by Leave-One-Out Cross-Validation. Furthermore the spatial reliability of the resultant map is also estimated by the calculation of the 90% prediction interval of the local prediction values. The applicability of the applied method as well as that of the map is discussed briefly. Copyright © 2015 Elsevier B.V. All rights

  12. Radon - environmental pollutant from underground. Radon - Umweltgift aus dem Erdreich

    Energy Technology Data Exchange (ETDEWEB)

    Obertreis, R.

    1988-01-01

    Radon is responsible for about 50% of the natural radiation load of 200 mrem/a in the Federal Republic of Germany. This implies that approximately 190.000 households with about 600.000 citizens of the Federal Republic face an increased risk of lung cancer. Hints are given as to the reduction of radon values in cellars and living rooms. (DG).

  13. Radon levels in the volcanic region of La Garrotxa, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Baixeras, C. [Grup de Fisica de les Radiacions. Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)]. E-mail: carmen.baixeras@uab.es; Bach, J. [Unitat de Geodinamica Externa. Departament de Geologia. Edifici Cs, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Amgarou, K. [Grup de Fisica de les Radiacions. Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Moreno, V. [Grup de Fisica de les Radiacions. Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Font, Ll. [Grup de Fisica de les Radiacions. Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)

    2005-11-15

    A preliminary survey in the city of Olot, the main town of the volcanic region of La Garrotxa, showed that dwellings built on volcanic formations present higher indoor radon levels than dwellings on non-volcanic materials. The soil of the area is not especially rich in radium. However, some of the volcanic materials present very high permeability and therefore radon entering the houses might have travelled over long distances. In this paper we present indoor radon values measured in a larger survey carried out during April-July 2004. The influence of the volcanic materials found in the preliminary survey has been confirmed. The results obtained suggest the possibility that radon comes from the degassification of mantle through active faults. The values obtained in working places do not constitute a relevant radiological risk for workers.

  14. Residential radon and lung cancer incidence in a Danish cohort

    DEFF Research Database (Denmark)

    Bräuner, Elvira Vaclavik; Andersen, Claus Erik; Sørensen, Mette

    2012-01-01

    non-smokers. We found no evidence of effect modification.We find a positive association between radon and lung cancer risk consistent with previous studies but the role of chance cannot be excluded as these associations were not statistically significant. Our results provide valuable information......High-level occupational radon exposure is an established risk factor for lung cancer. We assessed the long-term association between residential radon and lung cancer risk using a prospective Danish cohort using 57,053 persons recruited during 1993–1997. We followed each cohort member for cancer...... occurrence until 27 June 2006, identifying 589 lung cancer cases. We traced residential addresses from 1 January 1971 until 27 June 2006 and calculated radon at each of these addresses using information from central databases regarding geology and house construction. Cox proportional hazards models were used...

  15. Mapping radon-prone areas - a geophysical approach

    Energy Technology Data Exchange (ETDEWEB)

    Shirav, M. [Geological Survey of Israel, Jerusalem (Israel); Vulkan, U. [Soreq Nuclear Research Center, Yavne (Israel)

    1997-06-01

    Radon-prone areas in Israel were mapped on the basis of direct measurements of radon ({sup 222}Rn) in the soil/rock gas of all exposed geological units, supported by the accumulated knowledge of local stratigraphy and sub-surface geology. Measurements were carried out by a modified alpha-track detection system, resulting in high radon levels mainly in rocks of the Senonian-Paleocene-aged Mount Scopus Group, comprised of chert-bearing marly chalks, rich in phosphorite which acts as the major uranium source. Issues of source depth, seasonal variations and comparison with indoor radon levels are addressed as well. This approach could be applied to other similar terrains, especially the Mediterranean Phosphate Belt. (orig.)

  16. Radon, water chemistry and pollution check by volatile organic compounds in springs around Popocatepetl volcano, Mexico

    OpenAIRE

    Mena, M.; Cisniega, G.; Lopez, B.; M. A. Armienta; Valdés, C; Peña, P.; N. Segovia

    2005-01-01

    Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs were analysed as a function of the 2002-2003 volcanic activity. The measurements of soil radon indicated fluctuations related to both the meteorological and sporadic explosive events. Groundwater radon showed essential differences in concentration d...

  17. Environmental radon with RAD7 detector; Radon ambiental con detector RAD7

    Energy Technology Data Exchange (ETDEWEB)

    Lopez M, A.; Balcazar, M. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Fernandez G, I. M.; Capote F, E., E-mail: arturo.lopez@inin.gob.mx [Centro de Proteccion e Higiene de las Radiaciones, Carretera La Victoria II Km 2.5 e/ Monumental y Final, Guanabacoa, La Habana (Cuba)

    2016-09-15

    Experimental results of the radon detection with the equipment RAD7 are presented. The use of a solid state detector placed in a semi-spherical chamber with an electric field allows a high sensitivity of 0.4 cpm/P Ci/l. Radon detection is achieved by the spectroscopy of its decay products. In accordance with a table of errors for various ranges of counts and radon concentrations, reported by the manufacturer, an equation was obtained that allows establishing operation criteria of the equipment. For radon detection at ambient concentrations as low as 30 Bq m{sup -3}, is shown that short counts of 10 minutes are good enough to make decisions on radiation protection matter. In places where concentrations are close to 200 Bq m{sup -3}, counting intervals of the order of 0.5 hours will have an acceptable counting error of the order of 20%. The determination of radon in soil was, according to the expected, on the order of 10 kBq m{sup -3}, and was found that even with the recommended counting times of 5 minutes, there is a risk of increased humidity inside the detector above 20% Rh, with associated reduction of detection efficiency, if the desiccant is not used properly. The equipment was subjected to a radon exposure in air of 13, 373 Bq m{sup -3} ± 3.7%, contained within a controlled chamber, with a variation in temperature of (19-21) degrees Celsius and in the relative humidity of (5-7) %, the good stability of the chamber allows to propose calibration processes of these equipment s by assessing the concentration by means of a Ge (Hp) detector. (Author)

  18. Measurement of airborne radon concentrations at several sites in a radioactivity research laboratory.

    Science.gov (United States)

    Shimizu, M; Anzai, I

    1999-06-01

    Radon-222 is a natural, gaseous, radioactive nuclide released from the ground and building materials into the air. Radon and its daughter nuclides can be an important disturbance factor for the measurement of environmental radioactivity. Radon concentrations in air in a radiation laboratory were measured with PICO-RAD detectors, which directly adsorb radon gas on activated charcoal. Generally, radon concentration increased in the absence of ventilation; a high concentration was observed in a radioisotope storage room without ventilation. Concentrations were low in other rooms used for experiments and measurement, which suggests that the radiation control practice in this laboratory is satisfactory and that the influence of natural radon gas on the measurement of radioactivity is negligible.

  19. Comprehensive investigation of radon exposure in Austrian tourist mines and caves.

    Science.gov (United States)

    Gruber, V; Ringer, W; Gräser, J; Aspek, W; Gschnaller, J

    2014-11-01

    According to Austrian Law, dose assessments in workplaces with potentially enhanced radon exposures are mandatory since 2008, including tourist mines and caves. A pilot study was carried out to evaluate the situation to test the measurement methods and to specify the main parameters controlling the radon concentration in tourist mines and caves. Radon was measured in six mines and three caves for 1 y, along with determining thoron and equilibrium factors and taking into account climatic, geological and site-related effects. The radon concentrations have a seasonal dependence with maximum in summer and minimum in winter, related to natural ventilation. Radon concentrations in the karst caves were quite low, as it was in the salt mine, whereas radon concentrations in copper and silver mines were high. The dose assessment of the employees yielded doses above 6 mSv a(-1) only in the copper mine.

  20. A survey of radon concentrations in a monazite rich region

    Energy Technology Data Exchange (ETDEWEB)

    Magalhaes, Maisa H.; Melo, Vicente de Paula; Lauria, Dejanira C. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)]. E-mail: maisa@ird.gov.br

    2005-03-15

    This paper concerns to radon concentration in indoor and outdoor environments in a monazite rich regional and compares the obtained data with those from another Brazilian high radiation area, Pocos de Caldas region, and the radon concentration in a normal background radiation area, Rio de Janeiro city. The survey was performed by integrated measurements of radon in a period of three months in indoor and outdoor environments in Buena village, using a Solid State Nuclear Track Detectors Technique (SSNTD). The radon gas concentration in dwellings ranged from 28 Bq.m{sup -3} to 400 Bq.m{sup -3} and from 32 Bq.m{sup -3} to 300 Bq.m{sup -3} in outdoor environment. The high ventilation rate in the houses can explain the similar concentrations found indoor and outdoor. The median radon concentration in Buena dwellings (94 Bq.m{sup -3}) is twice higher than that one one of Rio de Janeiro city (40 Bq.m{sup -3}), whereas Pocos de Caldas region is twice higher (204 Bq.m{sup -3}) than Buena. The value of the median of radon outdoor concentration in Pocos de Caldas (130 Bq.m{sup -3}) is one and half higher than the Buena (89 Bq.m{sup -3}). (author)

  1. APPLICATION OF RADON REDUCTION METHODS

    Science.gov (United States)

    The document is intended to aid homeowners and contractors in diagnosing and solving indoor radon problems. It will also be useful to State and Federal regulatory officials and many other persons who provide advice on the selection, design and operation of radon reduction methods...

  2. Generation and control of thoron emanated from lantern mantles

    Science.gov (United States)

    Sorimachi, Atsuyuki; Sahoo, Sarata Kumar; Tokonami, Shinji

    2009-01-01

    This paper describes the performance of a thoron (R220n) flowthrough source made of a commercially available lantern mantle. This R220n source is easy to construct and operate and has a negligible radon (R222n) gas generated when the air was passed through the source. We studied the R220n concentration generated from the lantern mantles in terms of the variability in concentration associated with both the total weight of the lantern mantles used in the source and the air flow rate used in the experimental chamber. We found that the concentration of R220n generated in air ranged from 0.9 to 150 kBq m-3 and exponentially depended on the absolute humidity. The R220n concentration increased linearly with increasing total weight of the lantern mantles, but variations in the rate of air flow passed through the source had no influence on the observed R220n concentration.

  3. Modern state of radon chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Avrorin, V.V.; Krasikova, R.N.; Nefedov, V.D.; Toropova, M.A. (Leningradskij Gosudarstvennyj Univ. (USSR))

    1982-01-01

    A review of works on radon chemistry published up to May, 1980, is presented. Physical properties of the element, are described as well as peculiarities in the field of its chemical investigations connected with unfavourable nuclear-physical characteristics of radon isotopes, with specificity of its electron structure. Characteristics of the known radon compounds, including impurity compounds, their stability, are given. Possible chemical and nuclear-chemical approaches to the solution of problems of synthesis, determination of properties, and identification of its new compounds are discussed. The advantage of using electron capture processes for radon compound synthesis, possibility to use nuclear reactions induced by accelerated elementary particles, are pointed out. Possible applications of radon compounds are considered.

  4. Indoor radon exposure and lung cancer: a review of ecological studies.

    Science.gov (United States)

    Yoon, Ji Young; Lee, Jung-Dong; Joo, So Won; Kang, Dae Ryong

    2016-01-01

    Lung cancer has high mortality and incidence rates. The leading causes of lung cancer are smoking and radon exposure. Indeed, the World Health Organization (WHO) has categorized radon as a carcinogenic substance causing lung cancer. Radon is a natural, radioactive substance; it is an inert gas that mainly exists in soil or rock. The gas decays into radioactive particles called radon progeny that can enter the human body through breathing. Upon entering the body, these radioactive elements release α-rays that affect lung tissue, causing lung cancer upon long-term exposure thereto. Epidemiological studies first outlined a high correlation between the incidence rate of lung cancer and exposure to radon progeny among miners in Europe. Thereafter, data and research on radon exposure and lung cancer incidence in homes have continued to accumulate. Many international studies have reported increases in the risk ratio of lung cancer when indoor radon concentrations inside the home are high. Although research into indoor radon concentrations and lung cancer incidence is actively conducted throughout North America and Europe, similar research is lacking in Korea. Recently, however, studies have begun to accumulate and report important data on indoor radon concentrations across the nation. In this study, we aimed to review domestic and foreign research into indoor radon concentrations and to outline correlations between indoor radon concentrations in homes and lung cancer incidence, as reported in ecological studies thereof. Herein, we noted large differences in radon concentrations between and within individual countries. For Korea, we observed tremendous differences in indoor radon concentrations according to region and year of study, even within the same region. In correlation analysis, lung cancer incidence was not found to be higher in areas with high indoor radon concentrations in Korea. Through our review, we identified a need to implement a greater variety of

  5. A reconnaissance study of radon concentration in Hamadan city, Iran.

    Science.gov (United States)

    Gillmore, G. K.; Jabari Vasal, Naghi

    2009-04-01

    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 to 364 Bq/m3 with a mean value of 107.87 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 reconnaissance 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, although further work is required to confirm these results. 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 to distribute water underground, 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. Keywords: Radon; health; dwellings; clay floors; alluvial fan; surficial geology; Hamadan; Iran

  6. Residential radon and lung cancer incidence in a Danish cohort

    Energy Technology Data Exchange (ETDEWEB)

    Braeuner, Elvira V., E-mail: ole@cancer.dk [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Danish Building Research Institute, Aalborg University (Denmark); Andersen, Claus E. [Center for Nuclear Technologies, Radiation Research Division, Riso National Laboratory for Sustainable Energy, Technical University of Denmark, Roskilde (Denmark); Sorensen, Mette [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Jovanovic Andersen, Zorana [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Center for Epidemiology Screening, Department of Public Health, University of Copenhagen (Denmark); Gravesen, Peter [Geological Survey of Denmark and Greenland, Copenhagen (Denmark); Ulbak, Kaare [National Institute of Radiation Protection, Herlev (Denmark); Hertel, Ole [Department of Environmental Science, Aarhus University, Aarhus (Denmark); Pedersen, Camilla [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark); Overvad, Kim [Department of Epidemiology, School of Public Health, Aarhus University, Aarhus (Denmark); Tjonneland, Anne; Raaschou-Nielsen, Ole [Diet, Genes and Environment, Danish Cancer Society Research Centre, Copenhagen (Denmark)

    2012-10-15

    High-level occupational radon exposure is an established risk factor for lung cancer. We assessed the long-term association between residential radon and lung cancer risk using a prospective Danish cohort using 57,053 persons recruited during 1993-1997. We followed each cohort member for cancer occurrence until 27 June 2006, identifying 589 lung cancer cases. We traced residential addresses from 1 January 1971 until 27 June 2006 and calculated radon at each of these addresses using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate ratios (IRR) and 95% confidence intervals (CI) for lung cancer risk associated with residential radon exposure with and without adjustment for sex, smoking variables, education, socio-economic status, occupation, body mass index, air pollution and consumption of fruit and alcohol. Potential effect modification by sex, traffic-related air pollution and environmental tobacco smoke was assessed. Median estimated radon was 35.8 Bq/m{sup 3}. The adjusted IRR for lung cancer was 1.04 (95% CI: 0.69-1.56) in association with a 100 Bq/m{sup 3} higher radon concentration and 1.67 (95% CI: 0.69-4.04) among non-smokers. We found no evidence of effect modification. We find a positive association between radon and lung cancer risk consistent with previous studies but the role of chance cannot be excluded as these associations were not statistically significant. Our results provide valuable information at the low-level radon dose range.

  7. Residential radon and lung cancer incidence in a Danish cohort.

    Science.gov (United States)

    Bräuner, Elvira V; Andersen, Claus E; Sørensen, Mette; Andersen, Zorana Jovanovic; Gravesen, Peter; Ulbak, Kaare; Hertel, Ole; Pedersen, Camilla; Overvad, Kim; Tjønneland, Anne; Raaschou-Nielsen, Ole

    2012-10-01

    High-level occupational radon exposure is an established risk factor for lung cancer. We assessed the long-term association between residential radon and lung cancer risk using a prospective Danish cohort using 57,053 persons recruited during 1993-1997. We followed each cohort member for cancer occurrence until 27 June 2006, identifying 589 lung cancer cases. We traced residential addresses from 1 January 1971 until 27 June 2006 and calculated radon at each of these addresses using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate ratios (IRR) and 95% confidence intervals (CI) for lung cancer risk associated with residential radon exposure with and without adjustment for sex, smoking variables, education, socio-economic status, occupation, body mass index, air pollution and consumption of fruit and alcohol. Potential effect modification by sex, traffic-related air pollution and environmental tobacco smoke was assessed. Median estimated radon was 35.8 Bq/m(3). The adjusted IRR for lung cancer was 1.04 (95% CI: 0.69-1.56) in association with a 100 Bq/m(3) higher radon concentration and 1.67 (95% CI: 0.69-4.04) among non-smokers. We found no evidence of effect modification. We find a positive association between radon and lung cancer risk consistent with previous studies but the role of chance cannot be excluded as these associations were not statistically significant. Our results provide valuable information at the low-level radon dose range.

  8. Measurement of the deposited activity of the short-lived radon progeny in the human respiratory tract

    Energy Technology Data Exchange (ETDEWEB)

    Vezzu, G.; Butterweck-Dempewolf, G.; Schuler, C. [Paul Scherrer Inst., Villigen (Switzerland). Div. for Radiation Protection and Waste Management

    1998-12-31

    Volunteers were exposed in the radon chamber at Paul Scherrer Institut to an atmosphere enriched with highly unattached radon progeny. The deposited radon progeny activity in the respiratory tract of the volunteers was determined using a low level in-vivo counter. The detector arrangement and its calibration for the measurement of deposited radon progeny activity is described and the results for a mouth and a nose breathing volunteer are presented. For the nose breathing volunteer 55% of the deposited radon progeny activity was located in the head and the remaining 45% in the chest whereas for the mouth breathing volunteer 25% was located in the head and the remaining 75% in the chest. A mean clearance half-life for the deposited radon progeny from the respiratory tract of (2{+-}1) h was obtained from the analyses of the temporal behaviour of the deposited radon progeny activity in the head. (orig.)

  9. Anomalous radon concentration in a nuclear research facility

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar, M.; Pena, P., E-mail: miguel.balcazar@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-08-15

    Radon monitoring in more than 60 selected points were part of surveillance radiation activities in the nuclear center of Mexico; three major facilities were inspected, the TRIGA Mark III research reactor, the Tandem Van de Graaff Accelerator and the Pelletron electron Accelerator. During a major maintenance activities in the research reactor, the air extraction system was not functioning for more than a month causing of a radon build up exhaled from the massive concrete of the building, reaching concentrations in some places up to 2.1 kb m{sup -3}. The irradiation room at the Tandem Accelerator presented high radon concentrations up to nearly 5 kb m{sup -3}, manly in the trenches were pipes and electric wires are located, the radon source was identified as originated from small caves under the floor. Low radon concentrations were found inside a similar building where a Pelletron accelerator is located. The reasons for the abnormal radon concentrations and the mitigation actions to remove any risk for the worker are discussed in detail in this paper. (author)

  10. Radon in groundwater of eastern Doon valley, Outer Himalaya

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M. E-mail: vchoubey1@rediffmail.com; Bartarya, S.K.; Ramola, R.C

    2003-06-01

    The radon content in water may serve as a useful tracer for several geohydrological processes. The hydrodynamic factor, presence of radium in host rocks, as well as the soil porosity and permeability control its concentration in groundwater. In order to understand the factors that control the occurrence of radon in groundwater of Doon valley in Outer Himalaya, a total of 34 groundwater samples were collected from handpumps and tubewells covering three hydrogeological units/areas in the eastern part of Doon valley. Radon variation in tubewells and handpumps varies from 25.4{+-}1.8 to 92.5{+-}3.4 Bq/l with an average of 53.5{+-}2.6 Bq/l. A significant positive correlation between radon concentration and depth of the wells was observed in the Doiwala-Dudhli and Jolleygrant areas suggesting that radon concentration increases with drilling depth in areas consisting of sediments of younger Doon gravels, whereas samples of the Ganga catchment show negative correlation. The high radon levels at shallower depths in the Ganga catchment (consisting of fluvial terraces of Ganga basin) indicate uranium-rich sediments at shallower depth.

  11. Tracing and quantifying groundwater inflow into lakes using radon-222

    Directory of Open Access Journals (Sweden)

    T. Kluge

    2007-06-01

    Full Text Available Due to its high activities in groundwater, the radionuclide 222Rn is a sensitive natural tracer to detect and quantify groundwater inflow into lakes, provided the comparatively low activities in the lakes can be measured accurately. Here we present a simple method for radon measurements in the low-level range down to 3 Bq m−3, appropriate for groundwater-influenced lakes, together with a concept to derive inflow rates from the radon budget in lakes. The analytical method is based on a commercially available radon detector and combines the advantages of established procedures with regard to efficient sampling and sensitive analysis. Large volume (12 l water samples are taken in the field and analyzed in the laboratory by equilibration with a closed air loop and alpha spectrometry of radon in the gas phase. After successful laboratory tests, the method has been applied to a small dredging lake without surface in- or outflow in order to estimate the groundwater contribution to the hydrological budget. The inflow rate calculated from a 222Rn balance for the lake is around 530 m3 per day, which is comparable to the results of previous studies. In addition to the inflow rate, the vertical and horizontal radon distribution in the lake provides information on the spatial distribution of groundwater inflow to the lake. The simple measurement and sampling technique encourages further use of radon to examine groundwater-lake interaction.

  12. Citizen's Guide to Radon: The Guide to Protecting Yourself and Your Family from Radon

    Science.gov (United States)

    ... Agency Search Search Radon Contact Us Share A Citizen's Guide to Radon: The Guide to Protecting Yourself ... EPA’s About PDF page to learn more. A Citizen's Guide to Radon - Revised December 2016 (PDF) (16 ...

  13. 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 cra

  14. 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 cra

  15. Radon concentration variations between and within buildings of a research institute

    Energy Technology Data Exchange (ETDEWEB)

    Antignani, S., E-mail: sara.antignani@iss.i [Istituto Superiore di Sanita (Italian National Institute of Health), Viale Regina Elena, 299, I-00161 Roma (Italy); Bochicchio, F.; Ampollini, M.; Venoso, G.; Bruni, B.; Innamorati, S.; Malaguti, L.; Stefano, A. [Istituto Superiore di Sanita (Italian National Institute of Health), Viale Regina Elena, 299, I-00161 Roma (Italy)

    2009-10-15

    Radon concentration in indoor air has been measured in many countries in a large number of buildings - mainly in houses but also in apartments and workplaces - mostly as a result of the application of radon policies and regulation requirements. However, few systematic analyses are available on radon concentration variations within buildings and between close buildings, especially as regards workplaces; such variations can have a significant impact on indoor radon exposure evaluation, and ultimately on the assessment of the dose from radon received by workers. Therefore, a project was started in 2006 aimed to study the spatial variation of radon concentration among and within about 40 buildings of the Istituto Superiore di Sanita (ISS), a research institute of public health located in Rome over a small area of less than 1 km{sup 2}. Nuclear track detectors (CR-39) were used to measure radon concentration for two consecutive six-month periods, in more than 700 rooms of the surveyed buildings. The paper describes the project in detail and preliminary results regarding 558 rooms in 29 buildings. Coefficient of variation (CV) was calculated as a measure of relative variation of radon concentration between buildings, between floors, and between rooms on the same floor. The CV between buildings resulted quite high (88%), a lower CV (42%) was found for variation between floors, whereas room-to-room CV on the same floor ranged from 25% at first floor level to 48% at basement level. Floor mean ratios, with ground floor as the reference level, were calculated for each building in order to study the correlation between radon concentration and floor levels. Although no clear trend was observed, the average basement/ground floor ratio of radon concentrations resulted about 2.0, whereas the average sixth floor/ground floor ratio of radon concentrations was 0.5. Some discussion on the potential impact of the results of this study on policies and radon regulations are also included

  16. Radon measurements by nuclear track detectors in secondary schools in Oke-Ogun region, Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Obed, R.I., E-mail: rachelobed@yahoo.com [Department of Physics, University of Ibadan, Ibadan (Nigeria); Ademola, A.K. [Department of Physical Sciences, Bells University of Technology, Ota (Nigeria); Vascotto, M. [Italian National Institute of Nuclear Physics (INFN), Trieste (Italy); Giannini, G. [The Italian National Institute of Nuclear Physics (INFN), Trieste (Italy); Department of Physics, University of Trieste, Trieste (Italy)

    2011-11-15

    Radon measurements were performed in secondary schools in the Oke-Ogun area, South-west, Nigeria, by solid state nuclear track detectors (SSNTDs). About seventy CR-39 detectors were distributed in 35 high schools of the Oke-Ogun area. The CR-39 detectors were exposed in the schools for 3 months and then etched in NaOH 6 N solution at 90 deg. C for 3 h. The tracks were counted manually at the microscope and the radon concentration was determined at the Radioactivity Laboratory, Department of Physics, University of Trieste, Trieste, Italy. The overall average radon concentration in the surveyed area was 45 {+-} 27 Bq m{sup -3}. The results indicate no radiological health hazard. The research also focused on parameters affecting radon concentrations such as the age of the building in relation to building materials and floor number of the classrooms. The results show that radon concentrations in ground floors are higher than in upper floors. - Highlights: > We measured radon concentration levels in a sample of schools in Oke-Ogun, Nigeria. > We analyzed the main factors that affect indoor radon levels. > Dependence of radon concentrations on floor levels confirmed the influence of soil as main source of indoor radon.

  17. Use of a geographic information system (GIS) for targeting radon screening programs in South Dakota.

    Science.gov (United States)

    Kearfott, Kimberlee J; Whetstone, Zachary D; Rafique Mir, Khwaja M

    2016-01-01

    Because (222)Rn is a progeny of (238)U, the relative abundance of uranium may be used to predict the areas that have the potential for high indoor radon concentration and therefore determine the best areas to conduct future surveys. Geographic Information System (GIS) mapping software was used to construct maps of South Dakota that included levels of uranium concentrations in soil and stream water and uranium deposits. Maps of existing populations and the types of land were also generated. Existing data about average indoor radon levels by county taken from a databank were included for consideration. Although the soil and stream data and existing recorded average indoor radon levels were sparse, it was determined that the most likely locations of elevated indoor radon would be in the northwest and southwest corners of the state. Indoor radon levels were only available for 9 out of 66 counties in South Dakota. This sparcity of data precluded a study of correlation of radon to geological features, but further motivates the need for more testing in the state. Only actual measurements should be used to determine levels of indoor radon because of the strong roles home construction and localized geology play in radon concentration. However, the data visualization method demonstrated here is potentially useful for directing resources relating to radon screening campaigns.

  18. Fractal and Chaos Analysis for Dynamics of Radon Exhalation from Uranium Mill Tailings

    Science.gov (United States)

    Li, Yongmei; Tan, Wanyu; Tan, Kaixuan; Liu, Zehua; Xie, Yanshi

    2016-08-01

    Tailings from mining and milling of uranium ores potentially are large volumes of low-level radioactive materials. A typical environmental problem associated with uranium tailings is radon exhalation, which can significantly pose risks to environment and human health. In order to reduce these risks, it is essential to study the dynamical nature and underlying mechanism of radon exhalation from uranium mill tailings. This motivates the conduction of this study, which is based on the fractal and chaotic methods (e.g. calculating the Hurst exponent, Lyapunov exponent and correlation dimension) and laboratory experiments of the radon exhalation rates. The experimental results show that the radon exhalation rate from uranium mill tailings is highly oscillated. In addition, the nonlinear analyses of the time series of radon exhalation rate demonstrate the following points: (1) the value of Hurst exponent much larger than 0.5 indicates non-random behavior of the radon time series; (2) the positive Lyapunov exponent and non-integer correlation dimension of the time series imply that the radon exhalation from uranium tailings is a chaotic dynamical process; (3) the required minimum number of variables should be five to describe the time evolution of radon exhalation. Therefore, it can be concluded that the internal factors, including heterogeneous distribution of radium, and randomness of radium decay, as well as the fractal characteristics of the tailings, can result in the chaotic evolution of radon exhalation from the tailings.

  19. Synoptic estimates of diffuse groundwater seepage to a spring-fed karst river at high spatial resolution using an automated radon measurement technique

    Science.gov (United States)

    Khadka, Mitra B.; Martin, Jonathan B.; Kurz, Marie J.

    2017-01-01

    Groundwater (GW) seepage can provide a major source of water, solutes, and contaminants to rivers, but identifying magnitudes, directions and locations of seepage is complicated by its diffuse and heterogeneous distributions. However, such information is necessary to develop programs and policies for protecting ecosystems and managing water resources. Here, we assess GW seepage to the Ichetucknee River, a spring-fed, low gradient, gaining stream in north-central Florida, through automated longitudinal surveys of radon (222Rn) activities at three different flow conditions. A 222Rn mass balance model, which integrates groundwater and spring water end member 222Rn activities and longitudinal 222Rn distributions in river water, shows that diffuse groundwater seepage represents about 16% of the total river baseflow, consistent with previous results obtained from ion (Ca2+, Cl-, SRP and Fe) mass balances and dye tracer methods. During high river stage, the contribution from seepage increases to 18-23% of the river flow. The spatial distribution of GW seepage is more variable in the upper 2.2-km reach of the river than the lower 2.8-km reach, regardless of river flow conditions. The upper reach has a narrower flood plain than the lower reach, which limits evapotranspiration and increases hydraulic gradients toward the river following storm events. Seepage in the lower reach is also limited by hydrologic damming by the receiving river, which inundates the floodplain during high flow conditions, and reduces the hydraulic head gradient. These results demonstrate the variable nature of seepage to a gaining river in both time and space and indicate that multiple synoptic analyses of GW seepage are required to assess seepage rates, determine time-averaged solute fluxes, and develop optimal management policies for riverine ecosystems.

  20. Mapping geogenic radon potential by regression kriging

    Energy Technology Data Exchange (ETDEWEB)

    Pásztor, László [Institute for Soil Sciences and Agricultural Chemistry, Centre for Agricultural Research, Hungarian Academy of Sciences, Department of Environmental Informatics, Herman Ottó út 15, 1022 Budapest (Hungary); Szabó, Katalin Zsuzsanna, E-mail: sz_k_zs@yahoo.de [Department of Chemistry, Institute of Environmental Science, Szent István University, Páter Károly u. 1, Gödöllő 2100 (Hungary); Szatmári, Gábor; Laborczi, Annamária [Institute for Soil Sciences and Agricultural Chemistry, Centre for Agricultural Research, Hungarian Academy of Sciences, Department of Environmental Informatics, Herman Ottó út 15, 1022 Budapest (Hungary); Horváth, Ákos [Department of Atomic Physics, Eötvös University, Pázmány Péter sétány 1/A, 1117 Budapest (Hungary)

    2016-02-15

    Radon ({sup 222}Rn) gas is produced in the radioactive decay chain of uranium ({sup 238}U) which is an element that is naturally present in soils. Radon is transported mainly by diffusion and convection mechanisms through the soil depending mainly on the physical and meteorological parameters of the soil and can enter and accumulate in buildings. Health risks originating from indoor radon concentration can be attributed to natural factors and is characterized by geogenic radon potential (GRP). Identification of areas with high health risks require spatial modeling, that is, mapping of radon risk. In addition to geology and meteorology, physical soil properties play a significant role in the determination of GRP. In order to compile a reliable GRP map for a model area in Central-Hungary, spatial auxiliary information representing GRP forming environmental factors were taken into account to support the spatial inference of the locally measured GRP values. Since the number of measured sites was limited, efficient spatial prediction methodologies were searched for to construct a reliable map for a larger area. Regression kriging (RK) was applied for the interpolation using spatially exhaustive auxiliary data on soil, geology, topography, land use and climate. RK divides the spatial inference into two parts. Firstly, the deterministic component of the target variable is determined by a regression model. The residuals of the multiple linear regression analysis represent the spatially varying but dependent stochastic component, which are interpolated by kriging. The final map is the sum of the two component predictions. Overall accuracy of the map was tested by Leave-One-Out Cross-Validation. Furthermore the spatial reliability of the resultant map is also estimated by the calculation of the 90% prediction interval of the local prediction values. The applicability of the applied method as well as that of the map is discussed briefly. - Highlights: • A new method

  1. Radon risk management. Construction solutions

    Directory of Open Access Journals (Sweden)

    Borja Frutos Vázquez

    2011-12-01

    Full Text Available Radon gas is a radioactive element that appears in nature by the decay of radium found in terrestrial soils. This gas is able to travel between the pores of the ground and enter into the buildings where the concentration can increase and becoming a health risk to occupants from inhaling. The World Health Organization rate the radon gas as a level 1 carcinogen agent. According to this organization, radon is the second leading cause of lung cancer contraction after tobacco. Based on the perception of risk derived from epidemiological medical studies, some countries have established radon concentration values as safety limits, above which is recommended or required an architectural intervention to reduce levels. From an architectural perspective, there have been studies of several radon protection techniques to reduce radon immission in buildings or to evacuate it, in order to reduce the radon levels below the safety limits. This article develops some protection strategies that have been being used for these purposes, some of which have been tested in Spain thanks to a research project funded by the Nuclear Safety Council, and developed by the Eduardo Torroja Institute and the University of Cantabria.

  2. Determination of Geogenic Radon Potential (GEORP) in Pocos de Caldas - Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Marcelo T.; Silva, Nivaldo C.; Guerrero, Eder T.Z., E-mail: apoc@cnen.gov.br [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas; Navarro, Fabiano C.; Oliveira, Rodrigo J., E-mail: campus.pcaldas@unifal-mg.edu.br [Universidade Federal de Alfenas (UNIFAL), Pocos de Caldas, MG (Brazil). Instituto de Ciencia e Tecnologia

    2015-07-01

    The noble gas {sup 222}Rn is a radioactive isotope of the element radon that can be found in atmospheric air, among others gases, at broad range of concentration. This isotope decays from {sup 238}U series, which is normally found in soil and rocks, especially in fault zones and fractures, where uranium presents greater mobility. The atmospheric high concentration of this gas is frequently related to confined environments including dwellings and other buildings with low air ventilation rate. Inhalation of this gas is acknowledged by international agencies such as WHO, as the second leading cause of lung cancer, being the first among the non-smoker population. That is the reason why, some countries have defined their regions with high radon potential where it is justified the implementation of construction techniques to reduce indoor radon concentration. This paper uses the Geogenic Radon Potential (GEORP) approach aiming to identify radon prone areas in the urban zone of Pocos de Caldas - Brazil. GEORP encompasses simultaneous measurements of the soil gas permeability and radon soil gas concentration. This investigation was accomplished using RADON-JOK permeameter, a device specially developed for in situ soil gas permeability, and ALPHAGUARD, a professional radon monitor. A large variability was observed in both radon soil concentration and soil gas permeability. Some areas have presented low gas permeability due to clayey soil characteristics thus medium GEORP. The majority of the points in this paper have been identified with high radon soil gas concentration showing values that reached 1,000 kBq.m{sup -3} and presenting high radon index. (author)

  3. Map showing radon potential of rocks and soils in Montgomery County, Maryland

    Science.gov (United States)

    Gundersen, L.C.; Reimer, G.M.; Wiggs, C.R.; Rice, C.A.

    1988-01-01

    This report summarizes the radon potential of Montgomery County in the context of its geology. Radon is a naturally occurring gas produced by the radioactive decay of uranium. Radon produced by uraniferous rocks and soils may enter a house through porous building materials and through openings in walls and floors. Radon gases has a tendency to move from the higher pressure commonly existing in the soil to the lower pressure commonly existing in the house. The U.S. Environmental Protection Agency (U.S. EPA, 1986a) estimates that elevated levels of indoor radon may be associated with 5,000 to 20,000 of the 130,000 lung cancer deaths per year. They also estimate that 8 to 12 percent of the homes in the United States will have annual average indoor radon levels exceeding 4 picoCuries per liter of air (pCi/L). Above this level, the U.S. EPA recommends homeowners take remedial action. May factors control the amount of radon which may enter a home from the geologic environment. Soil drainage, permeability, and moisture content effect the amount of radon that can be released from rocks and soils (known as the emmanation) and may limit or increase how far it can migrate. Well drained, highly permeable soils facilitate the movement of radon. Soils with water content in the 8 to 15 percent range enhance the emmanation of radon (Lindmark, 1985). Daily and seasonal variations in soil and indoor radon can be caused by meteorologic factors such as barometric pressure, temperature, and wind (Clements and Wilkening, 1974; Schery and other, 1984). Construction practices also inhibit or promote entry of radon into the home (U.S. EPA, 1986b). In general, however, geology controls the source and distribution of radon (Akerblom and Wilson, 1982; Gundersen and others, 1987, 1988; Sextro and others, 1987; U.S. EPA, 1983; Peake, 1988; Peake and Hess, 1988). The following sections describe: 1) the methods used to measure radon and equivalent uranium (eU) in soil; 2) the radon potential

  4. A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies

    OpenAIRE

    Ogoma Sheila B; Moore Sarah J; Maia Marta F

    2012-01-01

    Abstract Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and ...

  5. A Systematic Review of Mosquito Coils and Passive Emanators: Defining Recommendations for Spatial Repellency Testing Methodologies.

    OpenAIRE

    Ogoma, SB; Moore, SJ; Maia, MF

    2012-01-01

    Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propos...

  6. 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.

  7. Guidance on Radon Resistant Construction and Radon Mitigation

    Science.gov (United States)

    This Unnumbered Letter regarding radon gas mitigation applies to all housing and community facilities, low-rise buildings and dwellings for the mentioned programs. Its intention is to guide staff to best serve our borrowers and protect their health.

  8. Geohydrological control on radon availability in groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Yogesh; Prasad, Ganesh [Department of Physics, H. N. B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal 249 199 (India); Choubey, V.M. [Wadia Institute of Himalayan Geology, Dehradun 248001 (India); Ramola, R.C. [Department of Physics, H. N. B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal 249 199 (India)], E-mail: rcramola@gmail.com

    2009-01-15

    The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fractured planes of bedrock. In this study, radon concentration in springs and hand pumps of Kumaun and Garhwal Himalaya, India was measured using radon emanometry technique. The study shows that radon concentration in springs and hand pumps is controlled by geohydrological characteristics, which in turn is also governed by tectonic processes.

  9. Neutron activation analysis of ceramic tiles and its component and radon exhalation rate

    Institute of Scientific and Technical Information of China (English)

    A. El-Shershaby; A. Sroor; F. Ahmed; A.S. Abdel-Haleem; Z. Abdel

    2004-01-01

    The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiated with reactor for 4 h( in the Second The gamma-ray spectra obtained were measured for several times by means of the hyper pure germanium detection system( HPGe).Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure the emanation rate of radon for these samples. The radium concentrations were found to vary from 0.39-3.59 ppm and the emanation rates were found to vary from (0.728-5.688) x 10-4The elemental analysis of the ceramic tiles and ceramic composites have a great importance in assigning the physical properties and in turn the quality of the material.

  10. VENTILATION INFLUENCE UPON INDOOR AIR RADON LEVEL

    Institute of Scientific and Technical Information of China (English)

    田德源

    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 indraft> exhaust plus indraft.

  11. Evolution of radon dose evaluation

    Directory of Open Access Journals (Sweden)

    Fujimoto Kenzo

    2004-01-01

    Full Text Available The historical change of radon dose evaluation is reviewed based on the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR reports. Since 1955, radon has been recognized as one of the important sources of exposure of the general public. However, it was not really understood that radon is the largest dose contributor until 1977 when a new concept of effective dose equivalent was introduced by International Commission on Radiological Protection. In 1982, the dose concept was also adapted by UNSCEAR and evaluated per caput dose from natural radiation. Many researches have been carried out since then. However, lots of questions have remained open in radon problems, such as the radiation weighting factor of 20 for alpha rays and the large discrepancy of risk estimation among dosimetric and epidemiological approaches.

  12. A Physician's Guide to Radon

    Science.gov (United States)

    This booklet has been developed for physicians by the U.S. Environmental Protection Agency in consultation with the American Medical Association (AMA). Its purpose is to enlist physicians in the national effort to inform the American public about radon.

  13. A Radon Progeny Deposition Model

    CERN Document Server

    Guiseppe, V E; Hime, A; Rielage, K; Westerdale, S

    2011-01-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly Rn-222) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of Pb-210 on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to depos...

  14. Is radon emission in caves causing deletions in satellite DNA sequences of cave-dwelling crickets?

    Directory of Open Access Journals (Sweden)

    Giuliana Allegrucci

    Full Text Available The most stable isotope of radon, 222Rn, represents the major source of natural radioactivity in confined environments such as mines, caves and houses. In this study, we explored the possible radon-related effects on the genome of Dolichopoda cave crickets (Orthoptera, Rhaphidophoridae sampled in caves with different concentrations of radon. We analyzed specimens from ten populations belonging to two genetically closely related species, D. geniculata and D. laetitiae, and explored the possible association between the radioactivity dose and the level of genetic polymorphism in a specific family of satellite DNA (pDo500 satDNA. Radon concentration in the analyzed caves ranged from 221 to 26,000 Bq/m3. Specimens coming from caves with the highest radon concentration showed also the highest variability estimates in both species, and the increased sequence heterogeneity at pDo500 satDNA level can be explained as an effect of the mutation pressure induced by radon in cave. We discovered a specific category of nuclear DNA, the highly repetitive satellite DNA, where the effects of the exposure at high levels of radon-related ionizing radiation are detectable, suggesting that the satDNA sequences might be a valuable tool to disclose harmful effects also in other organisms exposed to high levels of radon concentration.

  15. Radon,Lung Cancer Risk and Environmental Geology in Gejiu Area

    Institute of Scientific and Technical Information of China (English)

    卢伟; 王任重; 等

    1997-01-01

    The incidence of lung cancer in the Gejiu area of Yunnan Province ranks the first in the world.The radon level(indoor,soil) was measured in the Gejiu area by the SSNTD method from 1990 to 1996,The result indicates an extensive high-level of indoor radon in that area though U and Th are lower in local limestones,The indoor radon level of houses located in the geologic fault zone is 6 times high that 2km far from the fault zone.The reason probably is that the radon level of soil in the fault is 6-8 times high that 1 km far from the faults.our data indicate that a lower range of radon levels,0-100Bq.m-3,exists in healthy families.However,a higher radon level,over 800 Bq.m-3,is often found corresponding to that of cancer patients' homes(the house-owners are suffering from either lung cancer or leukaemia or liver cancer),Obviously,an increase in lung cancer incidence follows an increase in indoor radon level,The risk of cancer induced by indoor radon is no longer an inference,but a fact.

  16. Radon-safe building - questioning to municipal authorities; Radonturvallinen rakentaminen - kysely kuntien viranomaisille

    Energy Technology Data Exchange (ETDEWEB)

    Voutilainen, A.; Vesterbacka, K.; Arvela, H

    1998-12-01

    The study was carried out to find out radon prevention practices in municipalities with high indoor radon concentration. The investigated area consists of most of the Province of Southern Finland and the Regional Council of Tampere region. The questioning was made by phone to 95 municipal building authorities and to 55 health authorities in municipalities or joint of municipalities. The results were also compared to earlier questionings. About three of four of the investigated municipalities demanded or recommended to react to radon at least in certain area of the municipality, and only 30% of municipalities recommended to do so in the whole area. Most of the building authorities gave advises orally. More than half of them distributed copies of radon technical guides. The most important prevention measure against radon, radon tight foundation construction, was recommended only in a few municipalities. The existing guidance in writing is felt too difficult to decipher. Only about fifth of the municipalities verified that the builders were succeeded in the radon-safe construction by measuring indoor radon concentration in at least some of the new houses. As a proposal for action it is presented in the report that radon-safe construction should be recommended to all builders in the study area regardless of the soil type. The radon technical plans should be presented as drawings already when applying for the building permit. The success of the radon-safe building should be verified by check-up measurement on the municipality`s initiative. The co-operation with building and health authorities should be enhanced and the obligations clarified, and especially for building authorities tightened, so that healthier homes would be build in Finland. (author) 21 refs.

  17. Characterization of the Oum Er Rbia (Morocco) high basin karstic water sources by using solid state nuclear track detectors and radon as a natural tracer.

    Science.gov (United States)

    Khalil, N; Misdaq, M A; Berrazzouk, S; Mania, J

    2002-06-01

    Uranium and thorium contents as well as radon alpha-activities per unit volume were evaluated inside different water samples by using a method based on calculating the CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs) detection efficiencies for the emitted alpha-particles and measuring the resulting track density rates. The validity of the SSNTD technique utilized was checked by analysing uranyl nitrate (UO2(NO3)26H2O) standard solutions. A relationship between water radon concentration and water transmission of different water sources belonging to two regions of the Middle Atlas (Morocco) water reservoir was found. The influence of the water flow rate as well as the permeability and fracture system of the host rocks of the sources studied was investigated.

  18. Characterization of the Oum Er Rbia (Morocco) high basin karstic water sources by using solid state nuclear track detectors and radon as a natural tracer

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, N.; Misdaq, M.A. E-mail: misdaq@ucam.ac.ma; Berrazzouk, S.; Mania, J

    2002-06-01

    Uranium and thorium contents as well as radon {alpha}-activities per unit volume were evaluated inside different water samples by using a method based on calculating the CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs) detection efficiencies for the emitted {alpha}-particles and measuring the resulting track density rates. The validity of the SSNTD technique utilized was checked by analysing uranyl nitrate (UO{sub 2}(NO{sub 3}){sub 2}6H{sub 2}O) standard solutions. A relationship between water radon concentration and water transmission of different water sources belonging to two regions of the Middle Atlas (Morocco) water reservoir was found. The influence of the water flow rate as well as the permeability and fracture system of the host rocks of the sources studied was investigated.

  19. Effects of vegetation of radon transport processes in soil: The origins and pathways of {sup 222}Rn entering into basement structures. Final report, March 15, 1987--May 15, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Borak, T.B.

    1992-08-01

    The entry rate of {sup 22}Rn into a basement structure was measured continuously. These measurements demonstrated that radon entry did not vanish even when the structure was slightly pressurized. This persistent entry has been determined to be dominated by diffusion through the floor and walls and a combination of diffusion and convection through the floor-wall joint. The highest indoor radon concentrations occurred during calm periods when the pressure differentials between the inside and outside of the structure were small. The objectives of this work were to identify the origins of the radon and investigate the entry pathways. The radon could originate either in the concrete or in the soil surrounding the structure. Entry pathways into the basement were through the concrete floor and walls as well as through the floor-wall joint. The contributions of the origins and entry pathways were determined by continuously measuring the radon entry rate into the basement, using a trace gas system, and the flux density through portions of the floor and walls. Radon entry through the floor-wall joint could be controlled using a baseboard barrier system. Results indicated that, during calm conditions with wind speeds less than 1 m s{sup {minus}1}, 25 % of the radon enters through the floor-wall joint and 75 % enters through the concrete. About 30 % of the radon originated in the concrete floor and walls. A method for in-situ determination of the diffusion length and emanation fraction of radon in concrete was developed. For the concrete used in the structure, the average diffusion length and emanation fraction were 27{plus_minus}4 cm and 0.19{plus_minus}0.02 respectively.

  20. Quaternary deposits and weathered bedrock material as a source of dangerous radon emissions in Estonia

    Directory of Open Access Journals (Sweden)

    Petersell Valter

    2015-06-01

    Full Text Available The risk of dangerous radon emissions in Estonia is high, being among the highest in Europe. In almost 33 per cent of Estonian land area, the content of radon in soil-contained air exceeds the safe limit for unrestricted construction (50 kBq/m3. In such high radon-risk areas the concentration of radon in soil-contained air ranges from 50 to 400 kBq/m3, in a few cases reaching up to 2,100 kBq/m3 exceeding the permitted level for residential areas. The situation is particularly serious in the northernmost part of the country, where uranium-rich graptolite argillite (Dictyonema shale and the Obolus phosphorite are close to ground surface and their particles are constituent parts of Quaternary deposits. Radon emissions from bedrock have been investigated in detail, but to date Quaternary strata as a source of radon emissions are poorly studied. According to our measurements the highest concentrations of radon are related to tills containing clasts and fines of graptolite argillite and phosphorite. Glacial deposits include also granitoidal material, containing U, Th and K, which have been transported by glaciers from the outcrop areas of crystalline basement rocks in Finland and the Gulf of Finland. Due to weathering, outwash and repeated redeposition other genetic types are poorer in radioactive elements and they are weaker sources of radon.

  1. The influence of thoron on measurement results of radon exhalation rate

    CERN Document Server

    Xiao De Tao; Ling Qiu; Leung, J K C

    2002-01-01

    Because of thoron exhalation, the measurement results of radon exhalation rate using a local still method is usually larger than the true value of radon flux rate of the monitored material surface. The influence of sup 2 sup 1 sup 6 Po(ThA) on radon exhalation rate can be eliminated for sensitive radon monitors. Theoretical evaluations of the influence of sup 2 sup 1 sup 2 Bi(ThC) and sup 2 sup 1 sup 2 Po(ThC')on radon exhalation rate are carried out in a sampler with diameter of 188 mm, and height of 125 mm, and supplied electrostatic field inside (generated by high voltage and electret) under following conditions: the sampling time are 1, 2, 3 h, respectively, thoron exhalation rate is 100 times of radon's. The calculation results indicate that the measurement results of radon flux rate are possibly 35.5% larger than true value due to the influence of thoron for fast and multifunctional radon monitors with electret, high voltage, respectively and using CR-39 SSNTD as detector, but this influence is negligib...

  2. Estimating large-scale fractured rock properties from radon data collected in a ventilated tunnel

    Energy Technology Data Exchange (ETDEWEB)

    Unger, Andre; Finsterle, Stefan; Bodvarsson, Gudmundur S.

    2003-05-12

    To address regulatory issues regarding worker safety, radon gas concentrations have been monitored as part of the operation of a deep tunnel excavated from a highly fractured tuff formation. The objective of this study was to examine the potential use of the radon data to estimate large-scale formation properties of fractured rock. An iTOUGH2 model was developed to predict radon concentrations for prescribed ventilation rates. The numerical model was used (1) to estimate the permeability and porosity of the fractured formation at the length scale of the tunnel and extending tens of meters into the surrounding rock, and (2) to understand the mechanism leading to radon concentrations that potentially exceed the regulatory limit. The mechanism controlling radon concentrations in the tunnel is a function of atmospheric barometric fluctuations propagated down the tunnel. In addition, a slight suction is induced by the ventilation system. The pressure fluctuations are dampened in the fractured formation according to its permeability and porosity. Consequently, as the barometric pressure in the tunnel drops, formation gases from the rock are pulled into the opening, resulting in high radon concentrations. Model calibration to both radon concentration data measured in the tunnel and gas phase pressure fluctuations observed in the formation yielded independent estimates of effective, large-scale fracture permeability and porosity. The calibrated model was then used as a design tool to predict the effect of adjusting the ventilation-system operation strategy for reducing the probability that radon gas concentrations will exceed the regulatory limit.

  3. Modeling Joint Exposures and Health Outcomes for Cumulative Risk Assessment: The Case of Radon and Smoking

    Directory of Open Access Journals (Sweden)

    Jonathan I. Levy

    2011-09-01

    Full Text Available Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case example, given its large attributable risk, effect modification due to smoking, and significant variability in radon concentrations and smoking patterns. In spite of this fact, no study to date has estimated geographic and sociodemographic patterns of both radon and smoking in a manner that would allow for inclusion of radon in community-based cumulative risk assessment. In this study, we apply multi-level regression models to explain variability in radon based on housing characteristics and geological variables, and construct a regression model predicting housing characteristics using U.S. Census data. Multi-level regression models of smoking based on predictors common to the housing model allow us to link the exposures. We estimate county-average lifetime lung cancer risks from radon ranging from 0.15 to 1.8 in 100, with high-risk clusters in areas and for subpopulations with high predicted radon and smoking rates. Our findings demonstrate the viability of screening-level assessment to characterize patterns of lung cancer risk from radon, with an approach that can be generalized to multiple chemical and non-chemical stressors.

  4. Measurement of the radon concentration in an underground public facility and dose assessment. Fukuoka Tenjin Shopping Center

    Energy Technology Data Exchange (ETDEWEB)

    Narazaki, Yukinori [Fukuoka Inst. of Health and Environmental Sciences, Dazaifu (Japan); Tokonami, Shinji; Sanada, Tetsuya; Kanno, Nobuyuki; Yamada, Yuji

    2000-12-01

    Radon concentrations were measured with a passive radon detector from April 1998 through June 1999 in the Fukuoka Tenjin Underground Shopping Center to assess the dose affecting workers because of radon progeny inhalation. The radon concentration during the period was distributed from a range of 1.9 to 13.6 Bq/m{sup 3}. The arithmetic average concentration was estimated to be 6.9{+-}2.4 Bq/{sup 3}. The radon level was lower than that in dwellings in Japan and other countries. No spatial distribution of radon concentration was found in that area. From continuous measurement, the radon concentration was found to be high from midnight to noon and low in the afternoon. Little difference was noted between the daily average radon concentration and that during working hours. There was no seasonal variation. The equilibrium factor of 0.21{+-}0.10 was obtained during working hours. The activity-weighted size distribution of radon progeny was evaluated by using the number distribution of ambient aerosols and the classical attachment theory. Consequently, the activity median diameter was 150 nm. The unattached fraction of radon progeny was estimated to be 0.025 with an empirical equation. The annual effective dose of workers at the Tenjin center was calculated with the dose conversion factor from the UNSCEAR 1993 report and estimated to be 0.024 mSv/y. (author)

  5. 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.

  6. Radon in Estonian dwellings - Results from a National Radon Survey

    Energy Technology Data Exchange (ETDEWEB)

    Pahapill, Lia; Rulkov, Anne; Rajamaee, Raivo [Estonian Radiation Protection Centre (Kiirguskeskus), Tallinn (Spain); Aakerblom, Gustav [Swedish Radiation Protection Authority, Stockholm (Sweden)

    2003-10-01

    A countrywide survey of radon concentrations in Estonian dwellings was carried out during the period 1998-2001. The survey formed a part of the cooperation program on radiation protection between the Estonian Radiation Protection (Kiirguskeskus) Centre and the Swedish Radiation Protection Authority (SSI). The survey included measurements in a number of dwellings representative for Estonia in detached houses and multifamily buildings (only dwellings on the bottom floor were included in the survey). Altogether, radon concentrations were measured in 515 dwellings, a number large enough to be statistically significant. All measurements were made with alphatrack film detectors of the same type that SSI uses in Sweden. The measurements were made during a 2-3 month period during the winter half-year. Two detectors were used in each dwelling. In Estonia there are 0.17 million dwellings in detached houses and 0.45 million in multi apartment buildings. Of the 1.26 million inhabitants in Estonia. 0.36 million live in detached houses and 0.90 million in multi apartment buildings. Most of the latter were built during the Soviet occupation. Of the dwellings in multifamily buildings 30 % are assumed to be situated on the first floor. The mean radon concentration in dwellings in detached hoses, according to the survey results, is 103 Bq/m{sup 3}, in dwellings on the bottom floor in multi apartment buildings it is 78 Bq/m{sup 3}. In 1% of the dwellings the radon concentration exceeded 400 Bq/m{sup 3}. The highest radon concentration found in the study was 1040 Bq/m{sup 3}. Based on the assumption that the average radon concentration in the dwellings in multi-apartment buildings that are not situated on the bottom floor is 30 Bq/m{sup 3}, and that these dwellings constitute 70% of all dwellings in multi apartment buildings, the mean radon concentration in dwellings in multi apartment buildings is calculated to be 44 Bq/m{sup 3}. The mean value for all Estonia dwellings is calculated

  7. Radon legislation and national guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Aakerblom, G

    1999-07-01

    The International Commission on Radiological Protection (ICRP) and The Council of the European Union have recommended the Member States to take action against radon in homes and at workplaces. Within the EU project European Research into Radon in Construction Concerted Action, ERRICCA, the Topic Group on Legal and Building Code Impact was designated to study the current radon legislation and give advice regarding future enactment of laws and recommendations. On behalf of the Group, a questionnaire on radon legislation was sent out to nearly all European states and a selection of non-European states. Questions were asked regarding reference levels for dwellings, workplaces and drinking water, and about regulations or recommendations for building materials and city planning. All 15 EU Member States, 17 non-EU European countries and 10 non-European countries responded to the questionnaire. Their answers are considered current as of the end of 1998. Most European States and many non-European countries have recommended reference levels for dwellings and workplaces, and some have guidelines for measures against radon incorporated in their building codes and guidelines for construction techniques. However, only a few countries have enforced reference levels or regulations for planning and construction. The reference levels for indoor radon concentration in existing and new dwellings or workplaces are within the range 150-1000 Bq/m{sup 3}. Sweden is the only country (Out of 15 EU member states) which has enforced limits for existing dwellings. Sweden and the UK have both enforced levels for new dwellings. 7 non-European countries (Out of 17 responding countries) have enforced levels for existing dwellings and 9 have them for new dwellings. At the end of 1998, only Finland, Sweden, the Czech Republic, Romania, Russia and the Slovak Republic had limits for radon in water, although 8 countries were planning to introduce such limits. The present limits are within the range for

  8. Indoor radon, geogenic radon surrogates and geology - Investigations on their correlation.

    Science.gov (United States)

    Friedmann, H; Baumgartner, A; Bernreiter, M; Gräser, J; Gruber, V; Kabrt, F; Kaineder, H; Maringer, F J; Ringer, W; Seidel, C; Wurm, G

    2017-01-01

    The indoor radon concentration was measured in most houses in a couple of municipalities in Austria. At the same time the activity concentration of radium in soil, the soil gas radon concentration, the permeability of the ground and the ambient dose equivalent rate were also measured and the geological situations (geological units) were recorded too. From the indoor radon concentration and different house and living parameters a radon potential (Austrian radon potential) was derived which should represent the radon concentration in a standard room. Another radon potential (Neznal radon potential) was calculated from the soil gas radon concentration and the permeability. The aim of the investigation was to correlate all the different variables and to test if the use of surrogate data (e.g. geological information, ambient dose equivalent rate, etc.) can be used to judge the radon risk for an area without performing numerous indoor measurements.

  9. The Austrian radon activities on the way to the national radon action plan.

    Science.gov (United States)

    Gruber, V; Ringer, W; Wurm, G; Haider, W

    2014-07-01

    Based on the new Euratom Basic Safety Standards (BSS), all EU member states will be obliged to design a strategy to address long-term risks from radon exposure, which is laid down in the 'national radon action plan'. In Austria, the National Radon Centre is responsible for the development of the action plan. This paper presents the current and planned radon protection activities on the way to establish the radon action plan--like the national radon database, the definition of radon risk areas by improving the existing radon map, as well as strategies and activities to increase the radon awareness of the public and decision-makers and to involve the building sector. The impact of and the need for actions caused by the BSS requirements on the Austrian radon legislation, strategy and programme are discussed.

  10. Thermo-diffusional radon waves in soils.

    Science.gov (United States)

    Minkin, Leonid; Shapovalov, Alexander S

    2016-09-15

    A new theoretical framework for diurnal and seasonal oscillations of the concentration of radon in soil and open air is proposed. The theory is based on the existing temperature waves in soils and thermo-diffusional gas flux in porous media. As soil is a non-isothermal porous medium, usually possessing a large fraction of microscopic pores belonging to Knudsen's free molecular field, a thermo-diffusional gas flow in soil has to arise. The radon mass transfer equation in soil for sinusoidal temperature oscillations at the soil-atmosphere boundary is solved, which reveals that radon concentration behaves as a damped harmonic wave. The amplitude of radon concentration oscillations and phase shift between radon concentration oscillations and soil temperature depend on the radon diffusion coefficient in soil, rate of radon production, soil thermal conductivity, average soil temperature, decay constant, and heat of radon transfer. Primarily numerical calculations are presented and comparisons with experimental data are shown.

  11. 在高湿度环境下用活性炭盒测量氡浓度的研究%STUDY ON RADON CONCENTRATION MONITORING USING ACTIVATED CHARCOAL CANISTERS IN HIGH HUMIDITY ENVIRONMENTS

    Institute of Scientific and Technical Information of China (English)

    王月兴; 王海军; 杨翊方; 秦思昌; 王震涛; 张振江

    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℃),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.%本文研究了在高湿度环境中使用活性炭盒测量氡浓度时湿度对灵敏度的影响.所用的活性炭盒为圆柱形,每一个盒内装80 g活性炭.活性炭盒在相对湿度为68%、80%、88%和96%环境中(28℃)暴露48 h和72 h.在盒内被吸收的氡的量用氡子体214 Ph和214 Bi的γ射线计数确定.实验结果表明,在湿度相同情况下,计数随湿度的增高而降低,两个变量之间呈现负线性相关.在相对湿度68%到96%之间,湿度每增加1%,吸收氡的灵敏度减少约2.4%.在高湿度环境中,活性炭盒的暴露时间不宜超过3天.

  12. Measurements of indoor radon concentrations in Chaiya and Tha Chana districts, Surat Thani province, Thailand

    Science.gov (United States)

    Titipornpun, K.; Titipornpun, A.; Sola, P.; Bhongsuwan, T.

    2015-05-01

    Chaiya and Tha Chana districts of Surat Thani province are located in the areas with high levels of equivalent uranium at the ground surface, which have been identified as sources of radon. A survey measurement of indoor radon concentrations was carried out in 248 houses, using CR-39 detectors in closed cups. The geometric mean of indoor radon concentrations in Chaiya and Tha Chana districts were 26 ± 2 Bq·m-3 and 30 ± 2 Bq·m-3, respectively. Although the minimum radon concentration was 4 Bq·m-3 in both locations, the maximum radon concentration was found to be 159 Bq·m-3 in Tha Chana district, while it was 88 Bq·m-3 in Chaiya district. The level of radon concentrations above the action level (148 Bq·m-3) recommended by the United States Environmental Protection Agency was only found in two houses, which accounted for 1% of the total buildings surveyed in this present study. The majority of houses, which accounted for 94% of the total buildings surveyed, showed the radon concentration below the action level. As these houses had access to air flow during the daytime through open doors and windows, it is likely that such ventilation was sufficient to keep radon at a low concentration.

  13. Evaluation of Radon Pollution in Underground Parking Lots by Discomfort Index

    Directory of Open Access Journals (Sweden)

    AH Bu-Olayan

    2016-06-01

    Full Text Available Introduction Recent studies of public underground parking lots showed the influence of radon concentration and the probable discomfort caused by parking cars. Materials and Methods Radon concentration was measured in semi-closed public parking lots in the six governorates of Kuwait, using Durridge RAD7radon detector (USA. Results The peak radon concentration in the parking lots of Kuwait governorates was relatively higher during winter (63.15Bq/m3 compared to summer (41.73 Bq/m3. Radon in the evaluated parking lots revealed a mean annual absorbed dose (DRn: 0.02mSv/y and annual effective dose (HE: 0.06mSv/y.  Conclusion This study validated the influence of relative humidity and temperature as the major components of discomfort index (DI. The mean annual absorbed and effective dose  of radon in the evaluated parking lots were found below the permissible limits. However, high radon DRn and HE were reported when the assessment included the parking lots, the surrounding residential apartments, and office premises. Furthermore, the time-series analysis indicated significant variations of the seasonal and site-wise distribution of radon concentrations in the indoor evaluated parking lots of the six Kuwait governorates

  14. Development of radon {center_dot} thoron exhalation measuring system and its application

    Energy Technology Data Exchange (ETDEWEB)

    Saegusa, Jun; Yamasaki, Keizo; Yoshimoto, Takaaki; Okamoto, Kenichi; Tsujimoto, Tadashi [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.; Shimo, Michikuni

    1995-02-01

    As representative methods to determine radon/thoron exhalation rate from the surface of ground, we have used `accumulation method`, `adsorption method` or `vertical profile method`. These methods, however, are complicated in their procedures and not always measure radon/thoron activities directly. To make up for these weakness, we developed a radon/thoron exhalation in-situ measuring system with large-sized ZnS(Ag) scintillator. This system is basically composed of, skirt part which covers the ground, scintillation detector (30cmx40cm), light guide, photomultiplier tube, digital ratemeter, recorder (hand-held computer) and printer. The nuclides which accumulate in the skirt and contribute to counts are {sup 222}Rn, {sup 218}Po, and {sup 214}Po in the U-series, {sup 220}Rn, {sup 216}Po, in the Th-series. Each count due to radon and thoron can be distinguished from the difference of half time. We can assess exhalation rates readily and speedy using the counts of alpha particles from these nuclides. The calibration of the system was performed by the comparison with the accumulation method or the `flow method`. We applied this system on the spot located at Tsuruga district of Fukui prefecture in Japan. Radon/thoron concentrations at this spot is very high. To investigate the source of radon we used this system and the PICO-RAD system, and the relation between radon concentrations and radon exhalation rates will be reported. (author).

  15. Single-Particle Refinement and Variability Analysis in EMAN2.1.

    Science.gov (United States)

    Ludtke, S J

    2016-01-01

    CryoEM single-particle reconstruction has been growing rapidly over the last 3 years largely due to the development of direct electron detectors, which have provided data with dramatic improvements in image quality. It is now possible in many cases to produce near-atomic resolution structures, and yet 2/3 of published structures remain at substantially lower resolutions. One important cause for this is compositional and conformational heterogeneity, which is both a resolution-limiting factor and presenting a unique opportunity to better relate structure to function. This manuscript discusses the canonical methods for high-resolution refinement in EMAN2.12, and then considers the wide range of available methods within this package for resolving structural variability, targeting both improved resolution and additional knowledge about particle dynamics.

  16. Measurement of radon concentration in super-Kamiokande's buffer gas

    Science.gov (United States)

    Nakano, Y.; Sekiya, H.; Tasaka, S.; Takeuchi, Y.; Wendell, R. A.; Matsubara, M.; Nakahata, M.

    2017-09-01

    To precisely measure radon concentrations in purified air supplied to the Super-Kamiokande detector as a buffer gas, we have developed a highly sensitive radon detector with an intrinsic background as low as 0.33 ± 0.07 mBq /m3 . In this article, we discuss the construction and calibration of this detector as well as results of its application to the measurement and monitoring of the buffer gas layer above Super-Kamiokande. In March 2013, the chilled activated charcoal system used to remove radon in the input buffer gas was upgraded. After this improvement, a dramatic reduction in the radon concentration of the supply gas down to 0.08 ± 0.07 mBq /m3 . Additionally, the Rn concentration of the in-situ buffer gas has been measured 28.8 ± 1.7 mBq /m3 using the new radon detector. Based on these measurements we have determined that the dominant source of Rn in the buffer gas arises from contamination from the Super-Kamiokande tank itself.

  17. Scavenging of radon daughters by precipitation from the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Fujinami, Naoto [Kyoto Prefectural Inst. of Hygienic and Environmental Sciences (Japan)

    1997-02-01

    By the continuous measurement of the radon daughters concentration in the rain and snow water and atmosphere and the data analysis, the following results were obtained. The radon daughters concentration was almost constant in the rain and snow water in spite of the length during weather without precipitation. It has not tendency to show the high concentration of radon daughters in precipitation and snow during beginning of them. When the precipitation intensity is constant, it`s concentration does not change during precipitation and snowfall. The concentration does not depend on the amount of precipitation, but on the precipitation intensity. We did not observe a correlation between the radon daughters concentration in the rain and snow water and that in the surface air. The atmospheric concentration was decreased by precipitation and snowfall, but that of rain and snow water did not decrease. The above results seems to show that the contribution of washout under the cloud to radon daughters in rain and snow water is small and that of rainout in the cloud is large. This result is agreement with the Jacob`s experimental results. (S.Y.)

  18. Radon in Groundwater of the Northeastern Gran Canaria Aquifer

    Directory of Open Access Journals (Sweden)

    Héctor Alonso

    2015-05-01

    Full Text Available 222Rn has been detected in 28 groundwater samples from the northeast of Gran Canaria (Canary Islands, Spain utilizing a closed loop system consisting of an AlphaGUARD monitor that measures radon activity concentration in the air by means of an ionization chamber, and an AquaKIT set that transfers dissolved radon in the water samples to the air within the circuit. Radon concentration in the water samples studied varies between 0.3 and 76.9 Bq/L. Spanish radiological protection regulations limit the concentration of 222Rn for drinking water to 100 Bq/L, therefore the values obtained for all the analyzed samples are below this threshold. The hydrogeological study reveals a significant correspondence between the radon activity concentration and the material characteristics of the aquifer. For a selected group of samples with high radon concentrations, gross alpha activity has been determined to have values higher than the prescriptive screening level (0.1 Bq/L.

  19. Sampling and analysis for radon-222 dissolved in ground water and surface water

    Science.gov (United States)

    DeWayne, Cecil L.; Gesell, T.F.

    1992-01-01

    Radon-222 is a naturally occurring radioactive gas in the uranium-238 decay series that has traditionally been called, simply, radon. The lung cancer risks associated with the inhalation of radon decay products have been well documented by epidemiological studies on populations of uranium miners. The realization that radon is a public health hazard has raised the need for sampling and analytical guidelines for field personnel. Several sampling and analytical methods are being used to document radon concentrations in ground water and surface water worldwide but no convenient, single set of guidelines is available. Three different sampling and analytical methods - bubbler, liquid scintillation, and field screening - are discussed in this paper. The bubbler and liquid scintillation methods have high accuracy and precision, and small analytical method detection limits of 0.2 and 10 pCi/l (picocuries per liter), respectively. The field screening method generally is used as a qualitative reconnaissance tool.

  20. Determination of indoor radon concentrations at the elementary schools of Fatih district in Istanbul

    Science.gov (United States)

    Kurt, A.; Yalcin, L. Sahin; Oktem, Y.; Akkus, B.; Bozkurt, E.; Hafizoglu, N.; Ozturk, F. C.; Aytan, O.; Ertoprak, A.

    2016-03-01

    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 222Rn 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/m3. This results compared with Turkey's limits (400 Bq/m3) are low, conversely higher compared with WHO's limits (100 Bq/m3).

  1. A passive radon dosimeter based on the combination of a track etch detector and activated charcoal

    CERN Document Server

    Deynse, A V; Poffijn, A

    1999-01-01

    The aim of this work is to test a combination of a Makrofol track detector with a new type of charcoal (Carboxen-564) to design a personal radon dosimeter. The intention is to use this dosimeter as a personal radon dosimeter to measure the monthly radon exposure in workplaces, especially when the occupancy is not exactly known. The proposed combination was exposed to low and high concentrations of radon in a large range of relative humidity (RH). For the optimal layer thickness, a charcoal bed of 2.2 mm, a specific track density of 5.1 tracks cm sup - sup 2 /kBq h m sup - sup 3 was obtained. For a monthly working exposure (170 h) at an average radon concentration of 100 Bq/m sup 3 , this means 87 tracks/cm sup 2 or 10 times the background of the Makrofol detector, with a statistical uncertainty of 15%.

  2. Daily and seasonal variations in radon activity concentration in the soil air.

    Science.gov (United States)

    Műllerová, Monika; Holý, Karol; Bulko, Martin

    2014-07-01

    Radon activity concentration in the soil air in the area of Faculty of Mathematics, Physics and Informatics (FMPI) in Bratislava, Slovak Republic, has been continuously monitored since 1994. Long-term measurements at a depth of 0.8 m and short-term measurements at a depth of 0.4 m show a high variability in radon activity concentrations in the soil. The analysis of the data confirms that regular daily changes in radon activity concentration in the soil air depend on the daily changes in atmospheric pressure. It was also found that the typical annual courses of the radon activity concentration in the soil air (with summer minima and winter maxima) were disturbed by mild winter and heavy summer precipitation. Influence of precipitation on the increase in the radon activity concentration in the soil air was observed at a depth of 0.4 m and subsequently at a depth of 0.8 m.

  3. Measurements of 222Rn and 220Rn with a Large Size Collector of Radon Progeny

    Institute of Scientific and Technical Information of China (English)

    Wu Qifan; Jia Wenyi; Fang Fang; Wang Jun; Cheng Jianping; Liu Guilin; Zhu Li

    2003-01-01

    Radon concentrations in high background radiation areas in the south are higher than those of others in China, especially 220Rn concentration is significantly high. Therefore, measurements of 222Rn and 220 Rn concentrations should be carried out there. This paper introduces a large size collector of radon progeny and its applications. The collector is a sheet of polyvinyl chloride fiber with electrostatics of (-500 V) - ( -700 V). Its size (60 mm in diameter) is larger than those of others (26 mm in diameter) that work with the same principle. The collector is more effective to adsorb radon progeny than most of others. The equipment of ZnS(Ag) Scintillation Counting System is available for large size collectors to detect radon progeny. Therefore, its sensitivity of measurement is higher than that of others.According to the different half lives of radon progeny, and based on both theory and experiments, a formula for discrimination and calculation of 222 Rn and 220Rn concentrations is deduced. The 222Rn and 220Rn concentrations were surveyed with electrostatic collectors of radon progeny on the campus of com-mercial school and some other areas in Hainan, southern China. Neither 222Rn nor 220Rn concentration was found significantly high. However, several faults underground were delineated. The collector is also used to study radon transportation. Results indicate that radon changes regularly with date when it has transported for a certain distance. Velocities of radon migration in the four media are quite different.Radon migrates more quickly in vertical tube than in the horizontal tube.

  4. Modelling of radon transport in porous media

    NARCIS (Netherlands)

    van der Graaf, E.R.; de Meijer, R.J.; Katase, A; Shimo, M

    1998-01-01

    This paper aims to describe the state of the art of modelling radon transport in soil on basis of multiphase radon transport equations. Emphasis is given to methods to obtain a consistent set of input parameters needed For such models. Model-measurement comparisons with the KVI radon transport Facil

  5. Modelling of radon transport in porous media

    NARCIS (Netherlands)

    van der Graaf, E.R.; de Meijer, R.J.; Katase, A; Shimo, M

    1998-01-01

    This paper aims to describe the state of the art of modelling radon transport in soil on basis of multiphase radon transport equations. Emphasis is given to methods to obtain a consistent set of input parameters needed For such models. Model-measurement comparisons with the KVI radon transport Facil

  6. Reducing Radon in Schools: A Team Approach.

    Science.gov (United States)

    Ligman, Bryan K.; Fisher, Eugene J.

    This document presents the process of radon diagnostics and mitigation in schools to help educators determine the best way to reduce elevated radon levels found in a school. The guidebook is designed to guide school leaders through the process of measuring radon levels, selecting the best mitigation strategy, and directing the efforts of a…

  7. The Applicability of Traditional Protection Methods to Lines Emanating from VSC-HVDC Interconnectors and a Novel Protection Principle

    Directory of Open Access Journals (Sweden)

    Shimin Xue

    2016-05-01

    Full Text Available Voltage source converter (VSC-based high voltage direct current (VSC-HVDC interconnectors can realize accurate and fast control of power transmission among AC networks, and provide emergency power support for AC networks. VSC-HVDC interconnectors bring exclusive fault characteristics to AC networks, thus influencing the performance of traditional protections. Since fault characteristics are related to the control schemes of interconnectors, a fault ride-through (FRT strategy which is applicable to the interconnector operating characteristic of working in four quadrants and capable of eliminating negative-sequence currents under unbalanced fault conditions is proposed first. Then, the additional terms of measured impedances of distance relays caused by fault resistances are derived using a symmetrical component method. Theoretical analysis shows the output currents of interconnectors are controllable after faults, which may cause malfunctions in distance protections installed on lines emanating from interconnectors under the effect of fault resistances. Pilot protection is also inapplicable to lines emanating from interconnectors. Furthermore, a novel pilot protection principle based on the ratio between phase currents and the ratio between negative-sequence currents flowing through both sides is proposed for lines emanating from the interconnectors whose control scheme aims at eliminating negative-sequence currents. The validity of theoretical analysis and the protection principle is verified by PSCAD/EMTDC simulations.

  8. 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)

  9. Canadian Lung Cancer Relative Risk from Radon Exposure for Short Periods in Childhood Compared to a Lifetime

    Directory of Open Access Journals (Sweden)

    Jing Chen

    2013-05-01

    Full Text Available Long-term exposure to elevated indoor radon concentrations has been determined to be the second leading cause of lung cancer in adults after tobacco smoking. With the establishment of a National Radon Program in Canada in 2007 thousands of homes across the country have been tested for radon. Although the vast majority of people are exposed to low or moderate radon concentrations; from time to time; there are homes found with very high concentrations of radon. Among those living in homes with very high radon concentrations, it is typically parents of young children that demonstrate a great deal of concern. They want to know the equivalent risk in terms of the lifetime relative risk of developing lung cancer when a child has lived in a home with high radon for a few years. An answer to this question of risk equivalency is proposed in this paper. The results demonstrate clearly that the higher the radon concentration; the sooner remedial measures should be undertaken; as recommended by Health Canada in the Canadian radon guideline.

  10. Comparison of radon doses based on different radon monitoring approaches.

    Science.gov (United States)

    Vaupotič, Janja; Smrekar, Nataša; Žunić, Zora S

    2017-04-01

    In 43 places (23 schools, 3 kindergartens, 16 offices and one dwelling), indoor radon has been monitored as an intercomparison experiment, using α-scintillation cells (SC - Jožef Stefan Institute, Slovenia), various kinds of solid state nuclear track detectors (KfK - Karlsruhe Institute of Technology, Germany; UFO - National Institute of Radiological Sciences, Chiba, Japan; RET - University College Dublin, Ireland) and active electronic devices (EQF, Sarad, Germany). At the same place, the radon levels and, consequently, the effective doses obtained with different radon devices differed substantially (by a factor of 2 or more), and no regularity was observed as regards which detector would show a higher or lower dose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Mutagenicity of radon and radon daughters. Annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Evans, H.H.

    1991-12-01

    The objective of our research is to investigate the dose-response relationship of the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose rate dependence and the nature of the DNA lesion will be studied, using the thymidine kinase and HPRT loci to measure mutation frequency. A deficiency in DNA repair is shown to lead to a greater proportion of mutants with intergenic lesions. The cytotoxic effects of radon and its daughters are similar in human TK6 lymphoblasts and mouse L5178Y lymphoblasts, the cell line used in previous experiments. The results of molecular analysis of four spontaneous and 25 X-radiation induced HPRT{sup {minus}} mutants. Eleven radon-induced HPRT{sup {minus}} mutants have been isolated, and will be analyzed in a similar fashion. 9 figs.

  12. The history, development and the present status of the radon measurement programme in the United States of America.

    Science.gov (United States)

    George, A C

    2015-11-01

    The US radon measurement programme began in the late 1950s by the US Public Health Service in Colorado, New Mexico and Utah during the uranium frenzy. After the 1967 Congressional Hearings on the working conditions in uranium mines, the US Atomic Energy Commission (AEC) was asked to conduct studies in active uranium mines to assess the exposure of the miners on the Colorado Plateau and in New Mexico. From 1967 to 1972, the Health and Safety Laboratory of the US AEC in New York investigated more than 20 uranium mines for radon and radon decay product concentrations and particle size in 4 large uranium mines in New Mexico. In 1970, the US Environmental Protection Agency (EPA) was established and took over some of the AEC radon measurement activities. Between 1975 and 1978, the Environmental Measurements Laboratory of the US Department of Energy conducted the first detailed indoor radon survey in the USA. Later in 1984, the very high concentrations of radon found in Pennsylvania homes set the wheels in motion and gave birth to the US Radon Industry. The US EPA expanded its involvement in radon issues and assumed an active role by establishing the National Radon Proficiency Program to evaluate the effectiveness of radon measurement and mitigation methods. In 1998, due to limited resources EPA privatised the radon programme. This paper presents a personal perspective of past events and current status of the US radon programme. It will present an update on radon health effects, the incidence rate of lung cancer in the USA and the number of radon measurements made from 1988 to 2013 using short-term test methods. More than 23 million measurements were made in the last 25 y and as a result more than 1.24 million homes were mitigated successfully. It is estimated that radon measurements performed in the USA are made using long-term testing devices. The number of homes above the US action level of 148 Bq m(-3) (4 pCi l(-1)) may be ∼8.5 million because ∼50 million homes

  13. Indoor air radon concentration in schools in Prizren, Kosovo.

    Science.gov (United States)

    Bahtijari, Meleq; Stegnar, Peter; Shemsidini, Zahadin; Kobal, Ivan; Vaupotic, Janja

    2006-01-01

    Indoor air radon ((222)Rn) concentrations were measured in spring and winter in 30 rooms of 9 elementary schools and 19 rooms of 6 high schools in Prizren, Kosovo, using alpha scintillation cells. Only in three rooms of elementary schools and four rooms of high schools did winter concentrations exceed 400 Bq m(-3).

  14. Instruments to measure radon-222 activity concentration or exposure to radon-222. Intercomparison 2014; Messgeraete zur Bestimmung der Radon-222-Aktivitaetskonzentration oder der Radon-222-Exposition. Vergleichspruefung 2014

    Energy Technology Data Exchange (ETDEWEB)

    Foerster, Elisabeth; Beck, Thomas; Buchroeder, Helmut; Doering, Joachim; Schmidt, Volkmar

    2014-10-15

    According to the Directive 96/29/EURATOM the monitoring of occupational radiation exposures shall base on individual measurements carried out by an approved dosimetric service. Pursuant to the European Directive an approved dosimetric service is a body responsible for the calibration, reading or interpretation of individual monitoring devices.., whose capacity to act in this respect is recognized by the competent authorities. This concept will also be applied to radon services issuing passive radon measurement devices. Passive radon measurement devices{sup 1} using solid state nuclear track detectors or electrets are recommended for individual monitoring of exposures to radon. German regulations lay down that radon measuring devices are appropriate for purposes of occupational radiation monitoring if the devices are issued by recognized radon measurement services, and the measurement service submits devices of the same type issued for radon monitoring to regular intercomparisons conducted by the Bundesamt fuer Strahlenschutz (BfS). A radon measuring service is recognized by the competent authority if it proves its organisational and technical competence, e. g. by accreditation. These regulations have been introduced in the area of occupational radiation exposures. Nevertheless, it is recommended that radon measuring services which carry out radon measurements in other areas (e.g. dwellings) should subject themselves to these measures voluntarily. The interlaboratory comparisons comprise the organization, exposure, and evaluation of measurements of radon activity concentration or exposure to radon. The comparisons only concern radon-222; radon-220 is not in the scope. Radon services being interested can get further information from the European Information System on Proficiency Testing Schemes (EPTIS) and from the BfS websites.

  15. Correlation between geology and radon levels in groundwater, soil and indoor air in Bhilangana Valley, Garhwal Himalaya, India

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, V.M. [Wadia Inst. of Himalayan Geology, Dehra Dun (India); Ramola, R.C. [Dept. of Physics, H.N.B. Garhwal Univ. Campus, Tehri Garhwal (India)

    1997-11-01

    Radon concentrations were measured in soil, air and groundwater in Bhilangana Valley, Garhwal Himalaya, India by using an LR-115 plastic track detector and radon emanometer. Radon concentrations were found to vary from 1 KBq/m{sup 3} to 57 KBq/m{sup 3} in soil, 5 Bq/l to 887 Bq/l in water and 95 Bq/m{sup 3} to 208 Bq/m{sup 3} in air. The recorded values are quite high due to associated uranium mineralization in the area. Radon concentration was also found to depend on the tectonic structure and geology of the area. (orig.)

  16. Study on migration of radon in geologic environment by SSNTD

    Institute of Scientific and Technical Information of China (English)

    卢伟

    1996-01-01

    There is a high incidence of lung cancer in Gejiu area of Yunnan Province.Using method of SSNTD(solid state nuclear track detector),469 data of radon in the indoor or soil have been obtained.There is 471.9Bq.m-3 on an average in houses situated in geologic fault zone.None of ore of uranium or thorium has been found here.The migration of radon seems not"diffusion” bot“suction effect”。

  17. Update of Ireland's national average indoor radon concentration - Application of a new survey protocol.

    Science.gov (United States)

    Dowdall, A; Murphy, P; Pollard, D; Fenton, D

    2017-04-01

    In 2002, a National Radon Survey (NRS) in Ireland established that the geographically weighted national average indoor radon concentration was 89 Bq m(-3). Since then a number of developments have taken place which are likely to have impacted on the national average radon level. Key among these was the introduction of amending Building Regulations in 1998 requiring radon preventive measures in new buildings in High Radon Areas (HRAs). In 2014, the Irish Government adopted the National Radon Control Strategy (NRCS) for Ireland. A knowledge gap identified in the NRCS was to update the national average for Ireland given the developments since 2002. The updated national average would also be used as a baseline metric to assess the effectiveness of the NRCS over time. A new national survey protocol was required that would measure radon in a sample of homes representative of radon risk and geographical location. The design of the survey protocol took into account that it is not feasible to repeat the 11,319 measurements carried out for the 2002 NRS due to time and resource constraints. However, the existence of that comprehensive survey allowed for a new protocol to be developed, involving measurements carried out in unbiased randomly selected volunteer homes. This paper sets out the development and application of that survey protocol. The results of the 2015 survey showed that the current national average indoor radon concentration for homes in Ireland is 77 Bq m(-3), a decrease from the 89 Bq m(-3) reported in the 2002 NRS. Analysis of the results by build date demonstrate that the introduction of the amending Building Regulations in 1998 have led to a reduction in the average indoor radon level in Ireland. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Indoor radon measurements in Turkey dwellings.

    Science.gov (United States)

    Celebi, N; Ataksor, B; Taskın, H; Bingoldag, N Albayrak

    2015-12-01

    In this work, indoor radon radioactivity concentration levels have been measured in dwellings of Turkey within the frame of the National Radon Monitoring Programme. The (222)Rn concentrations were measured with time-integrating passive nuclear etched track detectors in 7293 dwellings in 153 residential units of 81 provinces, and the radon map of Turkey was prepared. Indoor radon concentrations were distributed in the range of 1-1400 Bq m(-3). The arithmetic mean of the radon gas concentration was found to be 81 Bq m(-3); the geometric mean was 57 Bq m(-3) with a geometric standard deviation of 2.3.

  19. Thermo-diffusional radon waves in soils

    Energy Technology Data Exchange (ETDEWEB)

    Minkin, Leonid, E-mail: lminkin@pcc.edu [Portland Community College, 12000 SW 49th Ave, Portland, OR 97219 (United States); Shapovalov, Alexander S. [Saratov State University, 83 Astrakhanskay Street, Saratov 410012 (Russian Federation)

    2016-09-15

    A new theoretical framework for diurnal and seasonal oscillations of the concentration of radon in soil and open air is proposed. The theory is based on the existing temperature waves in soils and thermo-diffusional gas flux in porous media. As soil is a non-isothermal porous medium, usually possessing a large fraction of microscopic pores belonging to Knudsen's free molecular field, a thermo-diffusional gas flow in soil has to arise. The radon mass transfer equation in soil for sinusoidal temperature oscillations at the soil–atmosphere boundary is solved, which reveals that radon concentration behaves as a damped harmonic wave. The amplitude of radon concentration oscillations and phase shift between radon concentration oscillations and soil temperature depend on the radon diffusion coefficient in soil, rate of radon production, soil thermal conductivity, average soil temperature, decay constant, and heat of radon transfer. Primarily numerical calculations are presented and comparisons with experimental data are shown. - Highlights: • Temperature oscillations in atmosphere generate radon waves in soil. • Radon flux in atmosphere is a harmonic function of time. • Radon concentration waves in soil have the same frequency as the temperature waves.

  20. 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})

  1. 30 CFR 57.5046 - Protection against radon gas.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection against radon gas. 57.5046 Section... Protection against radon gas. Where radon daughter concentrations exceed 10 WL, respirator protection against radon gas shall be provided in addition to protection against radon daughters. Protection against...

  2. Survey: Knowledge level of the population about radon in Switzerland; Enquete: niveau de connaissance de la population au sujet du radon en Suisse

    Energy Technology Data Exchange (ETDEWEB)

    Gruson, M.; Murith, C. [Office Federal de la Sante Publique, Section Risques Radiologiques, Berne (Switzerland); Rumo, S. [CBC Marketing Research, Berne (Switzerland)

    2010-01-15

    In 1995, a survey was conducted in order to investigate levels of knowledge about radon among the Swiss population. In 2008, a second survey, using a similar methodology, was carried out by the F.O.P.H.. The new study showed that about 40% of the Swiss population has heard of radon, which represents an increase of 8% over the 1995 survey. Most of the respondents knew that radon causes lung cancer, but believed that the gas also produces other health effects (in particular, migraine and skin conditions). In addition, older people, those with a high level of education and property owners tended to be more familiar with the radon issue than the public at large. The inhabitants of high-risk regions achieved markedly better results, which demonstrate that information campaigns in these regions have been successful. At the same time, additional communication efforts are required in low- and medium-risk municipalities, where the majority of the population lives. (authors)

  3. 76 FR 72006 - Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon...

    Science.gov (United States)

    2011-11-21

    ... COMMISSION Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon... Recovery Facility Surveys of Radon and Radon Progeny in Air and Demonstrations of Compliance with 10 CFR 20... that existing guidance does not sufficiently detail how the NRC staff reviews surveys of radon and...

  4. Measurements of {sup 222}Rn and{sup 220}Rn with a large size collector of radon progeny

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Qifan; Cheng, Jianping; Liu, Guilin; Zhu, Li [Tsinghua Univ., Beijing (China); Ja, Wenyi; Fang, Fang [Chengdu Univ. of Technology, Chengdu (China)

    2002-07-01

    People have paid more attention to radon since 1980s. Radon concentrations in high background radiation areas in the south are higher than others in China, especially {sup 220} Rn concentration is significantly high. Therefore, measurement of {sup 222} Rn and {sup 220} Rn concentration should be carried out there. I will introduce a large size collector of radon progeny and its applications in this paper. The collector is a sheet of polyvinyl chloride fibre with electrostatics of -500V {approx} -700V. Its size (60mm in diameter) is larger than others (26mm in diameter) that work as the same principle. The collector is more effective to adsorb radon progeny than most of others. The equipment of ZnS(Ag) Scintillation Counting System is available for large size collectors to detect radon progeny. Therefore its sensitivity of measurement is high than others. According to the different half life of radon progeny and based on both theory and experiment, a formula for discrimination and calculation of {sup 222} Rn and {sup 220} Rn concentrations was deduced. The {sup 222} Rn and {sup 220} Rn concentrations were surveyed with electrostatic collectors of radon progeny on the campus of commercial school and some other areas in Hainan, southern China. Neither {sup 222} Rn nor {sup 220} Rn concentrations were found significant high. However several faults underground were delineated. The collector is also used to study radon transportation. Results indicate that radon changes regularly with date when it has transported for a certain distance. Velocities of radon migration in the four media are quite different. Radon migrates more quickly in vertical tube than in the horizontal tube.

  5. Origin of radon concentration of Csalóka Spring in the Sopron Mountains (West Hungary).

    Science.gov (United States)

    Freiler, Ágnes; Horváth, Ákos; Török, Kálmán; Földes, Tamás

    2016-01-01

    We examined the Csalóka Spring, which has the highest radon concentration in the Sopron Mountains (West Hungary) (, yearly average of 227 ± 10 Bq L(-1)). The main rock types here are gneiss and micaschist, formed from metamorphism of former granitic and clastic sedimentary rocks respectively. The aim of the study was to find a likely source of the high radon concentration in water. During two periods (2007-2008 and 2012-2013) water samples were taken from the Csalóka Spring to measure its radon concentration (from 153 ± 9 Bq L(-1) to 291 ± 15 Bq L(-1)). Soil and rock samples were taken within a 10-m radius of the spring from debrish and from a deformed gneiss outcrop 500 m away from the spring. The radium activity concentration of the samples (between 24.3 ± 2.9 Bq kg(-1) and 145 ± 6.0 Bq kg(-1)) was measured by gamma-spectroscopy, and the specific radon exhalation was determined using radon-chamber measurements (between 1.32 ± 0.5 Bq kg(-1) and 37.1 ± 2.2 Bq kg(-1)). Based on these results a model calculation was used to determine the maximum potential radon concentration, which the soil or the rock may provide into the water. We showed that the maximum potential radon concentration of these mylonitic gneissic rocks (cpot = 2020 Bq L(-1)) is about eight times higher than the measured radon concentration in the water. However the maximum potential radon concentration for soils are significantly lower (41.3 Bq L(-1)) Based on measurements of radon exhalation and porosity of rock and soil samples we concluded that the source material can be the gneiss rock around the spring rather than the soil there. We determined the average radon concentration and the time dependence of the radon concentration over these years in the spring water. We obtained a strong negative correlation (-0.94 in period of 2007-2008 and -0.91 in 2012-2013) between precipitation and radon concentration.

  6. Regulatory developments in the control of exposure to radon in Spain; Avances reguladores en el control de la exposicion al radon en Espana

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Talavera, M.; Matarranz, J. L.; Salas, R.; Sanz, T.; Ramos, L.

    2013-06-01

    In this work, we give an overview on the current Spanish framework for the control of indoor radon exposure. CSN legislation is in line with the newest epidemiological evidences from Europe, China and North America and with ICRP new approach on radon. The concept of reference level has been has been used, with an emphasis on optimisation below it, and values of 600 Bq m{sup -}3 for, respectively, workplaces and dwellings have been set. Furthermore, because a key issue in national strategies to reduce radon exposure is the identification of areas most a risk for high levels indoors, we present the methodology followed to identify radon-prone areas in Spain. (Author) 20 refs.

  7. Radon safety in terms of energy efficiency classification of buildings

    Science.gov (United States)

    Vasilyev, A.; Yarmoshenko, I.; Zhukovsky, M.

    2017-06-01

    According to the results of survey in Ekaterinburg, Russia, indoor radon concentrations above city average level have been found in each of the studied buildings with high energy efficiency class. Measures to increase energy efficiency were confirmed to decrease the air exchange rate and accumulation of high radon concentrations indoors. Despite of recommendations to use mechanical ventilation with heat recovery as the main scenario for reducing elevated radon concentrations in energy-efficient buildings, the use of such systems did not show an obvious advantage. In real situation, mechanical ventilation system is not used properly both in the automatic and manual mode, which does not give an obvious advantage over natural ventilation in the climate of the Middle Urals in Ekaterinburg. Significant number of buildings with a high class of energy efficiency and built using modern space-planning decisions contributes to an increase in the average radon concentration. Such situation contradicts to “as low as reasonable achievable” principle of the radiation protection.

  8. Radon in indoor environments - a cost-benefit analysis of adoption of the new recommendations of WHO for radon limits; Radon i inomhusmiljoen - en konsekvensanalys av att infoera WHO:s nya rekommendationer paa radonvaerden

    Energy Technology Data Exchange (ETDEWEB)

    2010-10-15

    The report's goal is to investigate the consequences of the authorities to adopt the new WHO recommended limit and guideline for radon in homes of 100 Bq/m3. The report's purpose is to provide a basis for decision if the radon and radon guideline limit should be lowered. 400,000 houses and 230,000 apartments in Sweden have a radon concentration of 100-200 Bq/m3, and thus must be decontaminated of radon if the guideline value would be raised. This corresponds to about 1.3 million residents. The cost of such a radon mitigation is estimated at 14-19 billion SEK (2-3 billion USD). The increase in operating costs is estimated at 500 million SEK per year. Remediation measures are not economically reasonable. For the cost to be reasonable, 65-85 lung cancer cases should be prevented per year. Reduction in lung cancer cases, with a reduction in guideline value is estimated at 40 cases. Remediation costs for individual buildings with blue concrete can be very high. Close to 5000 people each year move into newly built homes with radon levels higher than 100 Bq/m3 under the 2010 construction forecast. The cost of mitigation measures necessary to bring down radon below 100 Bq/m3 for new constructions is estimated at 130 million SEK for 2010. These measures are not economically reasonable. For the cost to be reasonable 0.45 lung cancer cases should be prevented per year. The decrease in the number of lung cancers, with a reduction in the limit is estimated at 0.15 cases or new buildings. The Radon Coordinating Group recommends retaining the current target and limit for radon in dwellings of 200 Bq/m3. It is not economically reasonable to implement a tightening of the guide and limit values. The benchmark and the limit for radon should be remain unaltered. To have different guidelines and limits for old and new dwellings will create confusion in the industry and can lead to decreased respect for the limits. It is unclear whether there are ways to get down radon

  9. Low Radon Cleanroom at the University of Alberta

    Science.gov (United States)

    Grant, Darren; Hallin, Aksel; Hanchurak, Stephen; Krauss, Carsten; Liu, Shengli; Soluk, Richard

    2011-04-01

    A cleanroom laboratory designed to create and maintain a low concentration of radon in the air has been designed and is now under construction. We describe the clean room, the radon stripping system, and various radon monitoring tools.

  10. Radon, volatile organic compounds and water chemistry in springs around Popocatepetl volcano, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Segovia, N.; Pena, P.; Lopez, M.B.E.; Cisniega, G. [Inst. Nacional de Investigaciones Nucleares, Mexico D.F. (Mexico); Valdes, C.; Armienta, M.A.; Mena, M. [Inst. de Geofisica, UNAM, Ciudad Univ., Mexico D.F. (Mexico)

    2003-07-01

    Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs is analysed as a function of the 2002-2003 volcanic activity. Soil radon indicated fluctuations related both to the meteorological and sporadic explosive events. Groundwater radon showed essentially differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed also stability along the monitoring period indicating differences between springs. No anthropogenic pollution from volatile organic compounds was observed. (orig.)

  11. Risk assessment of exposure to radon decay products

    Energy Technology Data Exchange (ETDEWEB)

    Monchaux, G

    1999-07-01

    HRTM have been developed. These models form the basis of what would be required to calculate the equivalent dose to each of the rats used in the animal experiments. The main objective for the Human Studies Group was to conduct inhalation studies with human volunteers under well-defined conditions, to obtain a better experimental data base for dose calculations for inhaled radon progeny. The specific properties of the airborne radon progeny were characterised by two different modes to be studied, the unattached fraction, which has a size of about 1 nm, and the attached fraction where ambient aerosol particles are associated to radon progeny atoms. The studies included deposition patterns of the unattached fraction and the dependence of deposition on age and gender, the transfer or inhaled radon progeny to blood and the comparison of total deposition of radon progeny for adults and children in the domestic environment. In particular, the absorption half-time of unattached radon progeny from the respiratory tract to the blood was found to be shorter than the ICRP default value of 10 hours. In the Animal Studies Group, new series of experiments were carried out to investigate the influence of exposure-rate on lung cancer induction in rats at relatively low cumulative exposures. The preliminary results indicate that at relatively low cumulative exposures comparable to lifetime exposures in high-radon houses or current underground mining exposures, the risk of lung cancer in rats decreases with decreasing PAEC, i.e., exposure-rates. These data suggest that in terms of risk of induction of lung cancer, there is a complex interplay between cumulative exposure and exposure rate, resulting in an optimal exposure rate at a given exposure level. A positive dose rate response was seen for proliferating epithelial cells at relatively high exposure levels. The response of proliferating epithelial cells was found to depend on dose rate at higher doses, whereas at lower cumulative

  12. Characterization of blowholes as radon and thoron sources in the volcanic region of La Garrotxa, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, V., E-mail: victoria.moreno@uab.ca [Grup de Fisica de les Radiacions, Departament de Fisica, Edifici Cc, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain); Bach, J. [Unitat de Geodinamica Externa i d' Hidrogeologia, Departament de Geologia, Edifici Cs, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain); Baixeras, C.; Font, Ll. [Grup de Fisica de les Radiacions, Departament de Fisica, Edifici Cc, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)

    2009-10-15

    In the volcanic region of La Garrotxa there are natural holes in the soil from which a flow of air can reach the outdoor/indoor environment. In a previous study, these holes (called blowholes) have been found to have a big influence on indoor radon levels in a couple of houses. This finding triggered the interest to characterize these blowholes as radon/thoron sources. In this work, a total of 26 holes have been identified and characterized by geological field observations and by measuring their dimensions, air speed, temperature, humidity, and radon and thoron concentrations. Radon has been measured with passive (Makrofol) and active detectors (monitors PRASSI and RAD 7, being the latter used also to measure thoron). One of the indoor blowholes has been studied in detail and important temporal variations have been found, showing that radon levels are clearly correlated with the soil-outdoor temperature difference. There is not a significant radiological risk for the inhabitants and workers of the studied homes and workplaces with indoor blowholes. However, taking into account that in warm seasons buildings with blowholes in pyroclastic materials from volcanoes or in volcanic scoria under a compact lava flow may have high indoor radon levels (up to 1.5 kBq m{sup -3}) we conclude that volcanic regions with similar geological features and with presence of blowholes should be considered as areas with a potential radon/thoron radiological risk.

  13. Pooled analysis of two German studies on the lung cancer risk by radon in homes

    Energy Technology Data Exchange (ETDEWEB)

    Schaffrath Rosario, A.; Heid, I.M.; Kreuzer, M.; Heinrich, J.; Kreienbrock, L.; Wichmann, H.E. [GSF-National Research Center for Environment and Health, Inst. of Epidemiology, Neuherberg (Germany)

    2005-07-01

    Studies on underground miners have shown an increased risk of lung cancer after exposure to high doses of radon and radon daughters. However, in the range of typical indoor radon exposures, there are still some uncertainties about the strength of the association between radon exposure and the risk of lung cancer. Since 1990, population-based epidemiological studies have been performed in various countries in North America, Europe, and China. The pooled analysis of two large German case-control studies on the lung cancer risk due to radon in homes is described. The analysis is based on an extended dataset compared to previous publications, including 2,963 lung cancer cases and 4,232 population controls. A linear increase in the relative lung cancer risk of 0.10 (95% CI -0.02 to 0.39) is found. The risk estimates tend to be higher when measurement error in the radon concentrations is reduced. Furthermore, an outlook is given on the activities regarding the pooling of radon studies worldwide. (orig.)

  14. Human exposure to indoor radon: a survey in the region of Guarda, Portugal.

    Science.gov (United States)

    Louro, Alina; Peralta, Luís; Soares, Sandra; Pereira, Alcides; Cunha, Gilda; Belchior, Ana; Ferreira, Luís; Monteiro Gil, Octávia; Louro, Henriqueta; Pinto, Paulo; Rodrigues, António Sebastião; Silva, Maria João; Teles, Pedro

    2013-04-01

    Radon ((222)Rn) is a radioactive gas, abundant in granitic areas, such as the city of Guarda at the northeast of Portugal. This gas is recognised as a carcinogenic agent, being appointed by the World Health Organization as the second leading cause of lung cancer after tobacco smoke. Therefore, the knowledge of radon concentrations inside the houses (where people stay longer) is important from the point of view of radiological protection. The main goal of this study was to assess the radon concentration in an area previously identified with a potentially high level of residential radon. The radon concentration was measured using CR-39 detectors, exposed for a period of 2 months in 185 dwellings in the Guarda region. The radon concentration in studied dwellings, ranged between 75 and 7640 Bq m(-3), with a geometric mean of 640 Bq m(-3) and an arithmetic mean of 1078 Bq m(-3). Based on a local winter-summer radon concentration variation model, these values would correspond to an annual average concentration of 860 Bq m(-3). Several factors contribute to this large dispersion, the main one being the exact location of housing construction in relation to the geochemical nature of the soil and others the predominant building material and ventilation. Based on the obtained results an average annual effective dose of 15 mSv y(-1) is estimated, well above the average previously estimated for Portugal.

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

    Science.gov (United States)

    López-Coto, I; Mas, J L; Vargas, A; Bolívar, J P

    2014-09-15

    Nearly 1.0 × 10(8) tonnes of phosphogypsum were accumulated during last 50 years on a 1,200 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 (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 Bqm(-2)s(-1)) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bqm(-2)s(-1)).

  16. Radon Exposure, IL-6 Promoter Variants, and Lung Squamous Cell Carcinoma in Former Uranium Miners

    OpenAIRE

    2015-01-01

    Background: High radon exposure is a risk factor for squamous cell carcinoma, a major lung cancer histology observed in former uranium miners. Radon exposure can cause oxidative stress, leading to pulmonary inflammation. Interleukin-6 (IL-6) is a pro-carcinogenic inflammatory cytokine that plays a pivotal role in lung cancer development. Objectives: We assessed whether single nucleotide polymorphisms (SNPs) in the IL6 promoter are associated with lung cancer in former uranium miners with high...

  17. 9th Saxonian radon day. 11th meeting on radon safe structural engineering; 9. Saechsischer Radontag. 11. Tagung radonsicheres Bauen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    The proceedings of the meeting in radon-safe structural engineering covers contributions on the following issues: implementation of the EU standards, radon protection in underground cavities, radon protection at working places, reports on experiences.

  18. Study on the solubility of radon in tissues; Untersuchung der Loeslichkeit von Radon in Gewebe

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, Claudia; Kraft, Gerhard; Maier, Andreas; Beek, Patrick van [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)

    2016-08-01

    At the GSI Helmholtz Center in Darmstadt a radon chamber with conditions similar to the radon galleries was built for studies on the solubility of radon in tissues using cell cultures and animals. The samples are investigated using gamma spectroscopy following the radon exposure measuring Pb-214 and Bi-214. The original concentration of Rn-222 in the sample is determined by the time dependence of the decay rates of Rn-222. The experimental conditions and preliminary measurements are described.

  19. A European-wide 222Radon and 222Radon progeny comparison study

    OpenAIRE

    Schmithüsen, Dominik; Chambers, Scott; Fischer, Bernd; Gilge, Stefan; Hatakka, Juha; Kazan, Victor; Neubert, Rolf; Paatero, Jussi; Ramonet, Michel; Schlosser, Clemens; Schmid, Sabine; Vermeulen, Alex; Levin, Ingeborg

    2016-01-01

    A European-wide 222Radon/222Radon progeny comparison study has been conducted in order to determine correction factors that could be applied to existing atmospheric 222Radon data sets for quantitative use of this tracer in atmospheric transport model validation. Two compact and easy-to-transport Heidelberg Radon Monitors (HRM) were moved around to run for at least one month at each of the nine European measurement stations that were included in the comparison. Linear regressions between paral...

  20. The radon: evaluation and risk management; Le radon: evaluation et gestion du risque

    Energy Technology Data Exchange (ETDEWEB)

    Lacoste, A.C. [Direction Generale de la Surete Nucleaire et de la Radioprotection, 75 - Paris (France); Masse, R. [Academie des Technologies, 75 - Paris (France); Aurengo, A. [Hopital Pitie-Salpetriere, Service de Medecine Nucleaire, 75 - Paris (France); Erich Wichmann, H. [Neuberberg Munich Univ. (Germany); Timarche, M.; Laurier, D.; Robe, M.Ch. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Clamart (France); Baubron, J.C.; Bonijoly, D. [BRGM, 75 - Paris (France); Collignan, B. [Centre Scientifique et Technique du Batiment, (CSTB), 75 - Paris (France); Berrier, H. [Direction Gle de l' Urbanisme de l' Habitat et de la Construction, 75 - Paris (France); Jaouen, J. [Direction Departementale des Affaires Sanitaires et Sociales de la Haute-Vienne (France); Caamano, D. [Direction Departementale des Affaires Sanitaires et Sociales de l' Essonne, 91 (France); Guiot, F. [Direction Departementale des Affaires Sanitaires et Sociales de la Haute-Marne (France); Grall, B. [Direction Departementale des Affaires Sanitaires et Sociales de Bretagne (France); Frutos Vasquez, B.; Olaya Adan, M. [Istituto de Ciencias de la Construction (Italy); Garcia Cadierno, J.P.; Martin Matarranz, J.L.; Serrano Renedo, J.; Suarez Mahou, E. [Consejo de Seguridad Nuclear, Madrid (Spain); Fernandez, J.A. [ENUSA Industrias Avanzadas (Spain); Mjones, L.; Pirard, P. [Institut de veille sanitaire, 94415 - Saint-Maurice (France); Godet, J.L.; Rougy, Ch. [Direction Gle de la Surete Nucleaire et de la Radioprotection, 75 - Paris (France)

    2003-06-15

    The radon exposure constitutes for the French population the first cause of natural irradiation among the different natural sources of irradiation. It is possible to have a significant action on it, either by making draught proof in order to avoid to radon to get inside houses, either by ventilating in order to dispel the radon and improve air quality. (N.C.)

  1. Radon concentration measurements in bituminous coal mines.

    Science.gov (United States)

    Fisne, Abdullah; Okten, Gündüz; Celebi, Nilgün

    2005-01-01

    Radon measurements were carried out in Kozlu, Karadon and Uzülmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m(-3). It is suggested that the ventilation rates should be rearranged to reduce the radon concentration.

  2. Radon measurements in the Catalagzi Thermal Power Plant, Turkey.

    Science.gov (United States)

    Aytekin, H; Bayata, S; Baldik, R; Celebi, N

    2008-01-01

    The Catalağzi Thermal Power Plant (CTPP) (41(0)30'48.4('')N and 0.31(0)53'41.5('')E) is located at nearly 13 km North-east of Zonguldak city, which is located at the West Black Sea coast in Turkey. The middling products with high ash content of bituminous coals are used in this plant. Seasonal radon concentration measurements have been carried out by using CR-39 plastic track detectors in and around the CTPP. The annual average radon concentration has been found to vary from a minimum of 39.8 +/- 28.9 Bq m(-3) in the ash area to a maximum of approximately 75.0 +/- 15.7 Bq m(-3) in the service building of the power plant. The annual average radon concentration in the dwellings of the thermal power plant colony of the plant is 71.0 +/- 33.4 Bq m(-3). The effective dose has been found to vary from 0.38 to 0.71 mSv y(-1) with a mean value of 0.56 mSv y(-1), which is lower than the effective dose values 3-10 mSv given as the range of action levels recommended by International Commission on Radiological Protection: Protection against radon-222 at home and at work, ICRP Publication 65 (1993).

  3. Radon measurements in the Catalagzi Thermal Power Plant, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Aytekin, H.; Bayata, S.; Baldik, R.; Celebi, N. [Zonguldak Karaelmas University, Zonguldak (Turkey). Dept. of Physics

    2008-01-15

    The Catalagzi Thermal Power Plant (CTPP) is located at nearly 13 km North-east of Zonguldak city, which is located at the West Black Sea coast in Turkey. The middling products with high ash content of bituminous coals are used in this plant. Seasonal radon concentration measurements have been carried out by using CR-39 plastic track detectors in and around the CTPP. The annual average radon concentration has been found to vary from a minimum of 39.8 {+-} 28.9 Bq m{sup -3}) in the ash area to a maximum of about to 75.0 {+-} 15.7 Bq m{sup -3} in the service building of the power plant. The annual average radon concentration in the dwellings of the thermal power plant colony of the plant is 71.0 {+-} 33.4 Bq m{sup -3}. The effective dose has been found to vary from 0.38 to 0.71 mSv y{sup -1} with a mean value of 0.56 mSv y{sup -1}, which is lower than the effective dose values 3-10 mSv given as the range of action levels recommended by International Commission on Radiological Protection: Protection against radon-222 at home and at work, ICRP Publication 65 (1993).

  4. Radon exposure and tumors of the central nervous system.

    Science.gov (United States)

    Ruano-Ravina, Alberto; Dacosta-Urbieta, Ana; Barros-Dios, Juan Miguel; Kelsey, Karl T

    2017-03-15

    To review the published evidence of links between radon exposure and central nervous system tumors through a systematic review of the scientific literature. We performed a thorough bibliographic search in Medline (PubMed) and EMBASE. We combined MeSH (Medical Subject Heading) terms and free text. We developed a purpose-designed scale to assess the quality of the included manuscripts. We have included 18 studies, 8 performed on miners, 3 on the general population and 7 on children, and the results have been structured using this classification. The results are inconclusive. An association between radon exposure and central nervous system tumors has been observed in some studies on miners, but not in others. The results observed in the general adult population and in children are also mixed, with some research evincing a statistically significant association and others showing no effect. We cannot conclude that there is a relationship between radon exposure and central nervous system tumors. The available studies are extremely heterogeneous in terms of design and populations studied. Further research is needed in this topic, particularly in the general population residing in areas with high levels of radon. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. A perspective on risks from radon

    Energy Technology Data Exchange (ETDEWEB)

    Higson, D. J., E-mail: higsond@bigpond.net.a [Australasian Radiation Protection Society, PO Box 7108, Upper Ferntree Gully, Victoria 3156 (Australia)

    2010-10-15

    In its Statement on Radon (November 2009), the International Commission on Radiological Protection (ICRP) has reduced the upper reference level for radon gas in dwellings to 300 Bq m{sup -3}. The recommended level for workplaces is 1000 Bq m{sup -3}. A risk coefficient of 8 x 10{sup -10} per Bq h m{sup -3} is recommended without reference to smoking habits. On the basis of these figures: 1) The estimated risk of fatal cancer from exposure to radon at home and at work could be greater than the observed risk of accidental death from travelling by car, which would be surprising if true. 2) The estimated risk of lung cancer from radon could be greater than the observed risk of lung cancer from all causes, which is actually known to be dominated by smoking. The author is not aware of any direct evidence of risks from inhaling radon in Australian dwellings, 99% of which have radon levels below 50 Bq m{sup -3}. Evidence available from other countries shows that: 1) The effects of radon in the incidences of lung cancer are uncertain at levels less then about 50-100 Bq m{sup -3}. 2) The estimation of risks at levels below 200 Bq m{sup -3} depends on extrapolation from risks observed at higher levels. 3) Risks to non-smokers from radon are 25 times less than risks to smokers. Its concluded that the ICRP Statement on Radon and radon policies in the US and UK have the potential to cause unwarranted concern. Some people may be made to feel they need to spend money modifying their homes and workplaces to protect occupants from exposure to radon when there is no compelling reason to show that this is necessary. The vast majority of non-smokers do not need to be protected from radon. (Author)

  6. The radon influence of SAGE results

    CERN Document Server

    Gavrin, V N; Mirmov, I N

    2002-01-01

    The method for evaluating systematic errors, connected with radon, is described in the experiment on determining the SAGE solar neutrino flux. The systematic error by the measured neutrino capture rate in the gallium 75 SNU target does not exceed 0.3 SNU. The obtained value (0.3 SNU) is the upper limit of the radon systematic error. Its low value means, that radon does not contribute significantly to the SAGE result

  7. A Fuzzy Radon Transform for Track Recognition

    CERN Document Server

    De Laat, C T A M; CERN. Geneva; Lourens, W; Kamermans, R

    1993-01-01

    In this contribution a fuzzy Radon transform is shown for application in ALICE and ATLAS (typical track density of 8000 in one unit of rapidity). Resolution is introduced by the "broadening" of the matching tracks in the Radon transform, which is obtained by making a convolution of the matching tracks with Gaussian kernel. In a good approximation, an analytical expression for the fuzzy Radon transform is given. An example of two track separation with noisy input is added.

  8. Preliminary indoor radon risk assessment at the Pocos de Caldas Plateau, MG - Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Veiga, L.H.S. E-mail: Iene@ird.gov.br; Koifman, S.; Melo, V.P.; Sachet, I.; Amaral, E.C.S

    2003-07-01

    This paper aims to present an assessment of the environmental radiological exposure at a Brazilian area of high natural radiation and discusses the indoor radon exposure risk. A survey of inhabitant exposures arising from the inhalation of radon progeny and external gamma exposure was conducted in urban and rural areas of the Pocos de Caldas Plateau, which is recognized worldwide as a high natural radiation region. The results of this survey indicated that highest radiation exposure was restricted to the rural area of Pocos de Caldas. The radiation exposure in urban locations was quite similar to the values observed in normal background areas in some Brazilian counties. By the application of a constant relative risk model, an additional 20% in the lifetime risk of lung cancer mortality due to the exposure to radon progeny was estimated at Pocos de Caldas. It was also estimated that 16% of all lung cancer deaths at Pocos de Caldas county could be attributable to radon exposure.

  9. Spanish experience on the design of radon surveys based on the use of geogenic information.

    Science.gov (United States)

    Sainz Fernández, C; Quindós Poncela, L S; Fernández Villar, A; Fuente Merino, I; Gutierrez-Villanueva, J L; Celaya González, S; Quindós López, L; Quindós López, J; Fernández, E; Remondo Tejerina, J; Martín Matarranz, J L; García Talavera, M

    2017-01-01

    One of the requirements of the recently approved EU-BSS (European Basic Safety Standards Directive, EURATOM, 2013) is the design and implementation of national radon action plans in the member states (Annex XVIII). Such plans require radon surveys. The analysis of indoor radon data is supported by the existing knowledge about geogenic radiation. With this aim, we used the terrestrial gamma dose rate data from the MARNA project. In addition, we considered other criterion regarding the surface of Spain, population, permeability of rocks, uranium and radium contain in soils because currently no data are available related to soil radon gas concentration and permeability in Spain. Given that, a Spanish radon map was produced which will be part of the European Indoor Radon Map and a component of the European Atlas of Natural Radiation. The map indicates geographical areas with high probability of finding high indoor radon concentrations. This information will support legislation regarding prevention of radon entry both in dwellings and workplaces. In addition, the map will serve as a tool for the development of strategies at all levels: individual dwellings, local, regional and national administration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. A cost-effect analysis of an intervention against radon in homes

    Directory of Open Access Journals (Sweden)

    Hein Stigum

    2009-10-01

    Full Text Available Background  Key words  : Radon exposure, lung cancer, cost-effect analysis, attributable risk, models-mathematical: Radon is a radioactive gas that may leak into buildings from the ground. Radon exposure is a risk factor for lung cancer. An intervention against radon exposure in homes may consist of locating homes with high radon exposure (above 200 Bq m-3 and improving these, and of protecting future houses. The purpose of this paper is to calculate the costs and the effects of this intervention. Methods: We performed a cost-effect analysis from the perspective of the society, followed by an uncertainty and sensitivity analysis. The distribution of radon levels in Norwegian homes is lognormal with mean=74.5 Bq/m3, and 7.6% above 200 Bq/m3. Results: The preventable attributable fraction of radon on lung cancer was 3.8% (95% uncertainty interval: 0.6%, 8.3%. In cumulative present values the intervention would cost $238 (145, 310 million and save 892 (133, 1981 lives, each life saved costs $0.27 (0.09, 0.9 million. The cost-effect ratio was sensitive to the radon risk, the radon exposure distribution, and the latency period of lung cancer. Together these three parameters explained 90% of the variation in the cost-effect ratio. Conclusions: Reducing the radon concentration in present and future homes to below 200 Bq/m3 will cost $0.27 (0.09, 0.9 million per life saved. The uncertainty in the estimated cost per life is large, mainly due to uncertainty in the risk of lung cancer from radon. Based on estimates from road construction, the Norwegian society has been willing to pay $1 million to save a life. We therefore conclude that the intervention against radon in homes is justifiable. The willingness to pay is also larger that the upper uncertainty limit of the cost per life. Our conclusion is therefore robust against the uncertainties in the parameters.

  11. Radon atlas of Finland; Suomen radonkartasto

    Energy Technology Data Exchange (ETDEWEB)

    Voutilainen, A.; Maekelaeinen, I.; Pennanen, M.; Reisbacka, H.; Castren, O.

    1997-11-01

    The most efficient means of reducing indoor radon exposure is to locate and mitigate dwellings with radon concentration exceeding the action level of 400 Bq/m{sup 3} and to build new houses so that radon concentrations do not exceed 200 Bq/m{sup 3}. The maps and tables in this report are useful tools for those who plan and decide what kind of radon mitigation measures are needed in municipalities. STUK (The Radiation and Nuclear Safety Authority) has an indoor radon database of 52 000 dwellings, for which the indoor radon concentration and construction details are known. The building site soil type of about 38 000 dwellings is known. This atlas is a summary of all indoor radon measurements made by STUK in lowrise dwellings and in first-floor flats. The results are shown as arithmetic means of 5- or 10-km squares on maps of the provinces. Three radon maps have been made for each province. On one map the data consist of all measurements the position coordinates of which are known. On the two other maps the building sites of houses are classified into permeable and low-permeable soil types. The tables show statistics for all indoor radon measurements by municipality and building site soil type. (orig.). 11 refs. The publication contains all texts both in Finnish and in English.

  12. Radon transfer and intracorporal deposition of radon decay products under balneotherapeutic conditions; Radon-Transfer und intrakorporale Deposition von Radon-Folgeprodukten unter balneotherapeutischen Bedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Grunewald, Wolfgang A. [Kurmittelhaus Sibyllenbad, Neualbenreuth (Germany); Just, Guenther [Forschungsbuero Radon, Grosspoesna (Germany); Petzold, Juergen [Klinik und Poliklinik fuer Nuklearmedizin, Universitaetsklinikum, Leipzig (Germany); Philipsborn, Henning von [Radiometrisches Seminar, Univ. Regensburg (Germany)

    2009-07-01

    The intracorporal deposition of radon decay products was determined on four persons after 40 and 30 min respectively in radon water with about 1500 Bq/L by whole-body gamma spectrometry. The measurements started about 2 1/2h after exposure. In addition, the radon activity concentration of inspiratory and expiratory air was measured on one person during and after exposure and the deposition of radon decay products on the skin was measured on another person. The radon activity leaving the body with the expiratory air during exposure in the water (called ''radon transfer'') amounts to about 800 Bq. An intracorporal radon activity immediately after therapeutic exposure of about 3000 Bq was obtained as a result of first measurements by extrapolation from measurements starting about 2 1/2 hours later. Additional studies are necessary. There are indications that both the radon transfer and the intracorporal deposition can be increased by exposure in mixed radon-CO{sub 2} water. (orig.)

  13. 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.

  14. Indoor Radon in Micro-geological Setting of an Indigenous Community in Canada: A Pilot Study for Hazard Identification.

    Science.gov (United States)

    Sarkar, Atanu; Wilton, Derek Hc; Fitzgerald, Erica

    2017-04-01

    Radon is the second leading cause of lung cancer after smoking. In Canada, the health authorities have no access to comprehensive profile of the communities built over uranium-rich micro-geological settings. The present indoor radon monitoring guideline is unable to provide an accurate identification of health hazards due to discounting several parameters of housing characteristics. To explore indoor radon levels in a micro-geological setting known for high uranium in bedrock and to develop a theoretical model for a revised radon testing protocol. We surveyed a remote Inuit community in Labrador, located in the midst of uranium belt. We selected 25 houses by convenience sampling and placed electret-ion-chamber radon monitoring devices in the lowest levels of the house (basement/crawl space). The standard radon study questionnaire developed and used by Health Canada was used. 7 (28%) houses had radon levels above the guideline value (range 249 to 574 Bq/m(3)). Housing characteristics, such as floors, sump holes, ventilation, and heating systems were suspected for high indoor radon levels and health consequences. There is a possibility of the existence of high-risk community in a low-risk region. The regional and provincial health authorities would be benefited by consulting geologists to identify potentially high-risk communities across the country. Placing testing devices in the lowest levels provides more accurate assessment of indoor radon level. The proposed protocol, based on synchronized testing of radon (at the lowest level of houses and in rooms of normal occupancy) and thorough inspection of the houses will be a more effective lung cancer prevention strategy.

  15. Indoor Radon in Micro-geological Setting of an Indigenous Community in Canada: A Pilot Study for Hazard Identification

    Directory of Open Access Journals (Sweden)

    Atanu Sarkar

    2017-04-01

    Full Text Available Background: Radon is the second leading cause of lung cancer after smoking. In Canada, the health authorities have no access to comprehensive profile of the communities built over uranium-rich micro-geological settings. The present indoor radon monitoring guideline is unable to provide an accurate identification of health hazards due to discounting several parameters of housing characteristics. Objective: To explore indoor radon levels in a micro-geological setting known for high uranium in bedrock and to develop a theoretical model for a revised radon testing protocol. Methods: We surveyed a remote Inuit community in Labrador, located in the midst of uranium belt. We selected 25 houses by convenience sampling and placed electret-ion-chamber radon monitoring devices in the lowest levels of the house (basement/crawl space. The standard radon study questionnaire developed and used by Health Canada was used. Results: 7 (28% houses had radon levels above the guideline value (range 249 to 574 Bq/m3. Housing characteristics, such as floors, sump holes, ventilation, and heating systems were suspected for high indoor radon levels and health consequences. Conclusion: There is a possibility of the existence of high-risk community in a low-risk region. The regional and provincial health authorities would be benefited by consulting geologists to identify potentially high-risk communities across the country. Placing testing devices in the lowest levels provides more accurate assessment of indoor radon level. The proposed protocol, based on synchronized testing of radon (at the lowest level of houses and in rooms of normal occupancy and thorough inspection of the houses will be a more effective lung cancer prevention strategy.

  16. Durability of radon remedial actions

    Energy Technology Data Exchange (ETDEWEB)

    Naismith, S. [National Radiological Protection Board, Chilton (United Kingdom)

    1997-07-01

    It is estimated that at least 3600 householders in the UK have taken remedial action to reduce radon concentrations found to be above the government Action Level. A study has been carried out on the durability of these remedial actions. It involved annual reassessment of the radon levels in a number of homes. The results for 26 of these homes where data over five years are available show that in general the remedial actions remained effective. The remedy with the largest variation in efficacy was natural ventilation of the underfloor void. The failure rate was found to be 4.0% per annum for all measures, but in the majority of cases the failure was discovered by the householder and rectified. The rate of failures not noticed by the householders was 0.4% per annum. (UK).

  17. Activity of radon (222Rn) in the lower atmospheric surface layer of a typical rural site in south India

    Science.gov (United States)

    Kumar, K. Charan; Prasad, T. Rajendra; Ratnam, M. Venkat; Nagaraja, Kamsali

    2016-09-01

    Analysis of one year measurements of in situ radon (222Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth's surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5∘N and 79.2∘E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon in relation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence of rocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon (R = - 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be 12.01±0.66 Bq m-3 and 4.25±0.18 Bq m-3 for its progenies, in the study period.

  18. Activity of radon (222Rn) in the lower atmospheric surface layer of a typical rural site in south India

    Science.gov (United States)

    Kumar, K. Charan; Prasad, T. Rajendra; Ratnam, M. Venkat; Nagaraja, Kamsali

    2016-10-01

    Analysis of one year measurements of in situ radon (222Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth's surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5∘N and 79.2∘E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon in relation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence of rocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon ( R = - 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be 12.01±0.66 Bq m-3 and 4.25±0.18 Bq m-3 for its progenies, in the study period.

  19. Activity of radon ($^{222}$Rn) in the lower atmospheric surface layer of a typical rural site in south India

    Indian Academy of Sciences (India)

    K Charan Kumar; T Rajendra Prasad; M Venkat Ratnam; Nagaraja Kamsali

    2016-10-01

    Analysis of one year measurements of in situ radon ($^{222}$Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth’s surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5◦N and 79.2◦E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon inrelation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence ofrocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon (R = – 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be12.01±0.66 Bq m$^{−3}$ and 4.25±0.18 Bq m$^{−3}$ for its progenies, in the study period.

  20. Preparation and emanation properties of an ion-exchanged solid thoron source.

    Science.gov (United States)

    Tang, F; Zhuo, W; He, L; Zhao, C; Xu, Y

    2012-11-01

    For the calibration purpose of thoron ((220)Rn) measurements, solid sources with constant (220)Rn emanation are generally desired. In this study, Th(4+) in the thorium nitrate powder was successfully exchanged to the surfaces of sodium benzenesulphonate resins with a bead diameter of ∼0.5 mm by using the ion-exchange method. Tests of (220)Rn emanating from the ion-exchanged resin indicated that the emanation rates were nearly constant, provided both the air humidity and air temperature were controlled. As the resin can be easily prepared to be of various sizes and activities of sources, the ion-exchanged resin is considered as a promising standard source for calibrations of (220)Rn measurements.

  1. Lung Cancer Mortality and Radon Concentration in a Chronically Exposed Neighborhood in Chihuahua, Mexico: A Geospatial Analysis

    Directory of Open Access Journals (Sweden)

    Octavio R. Hinojosa de la Garza

    2014-01-01

    Full Text Available This study correlated lung cancer (LC mortality with statistical data obtained from government public databases. In order to asses a relationship between LC deaths and radon accumulation in dwellings, indoor radon concentrations were measured with passive detectors randomly distributed in Chihuahua City. Kriging (K and Inverse-Distance Weighting (IDW spatial interpolations were carried out. Deaths were georeferenced and Moran’s I correlation coefficients were calculated. The mean values (over n=171 of the interpolation of radon concentrations of deceased’s dwellings were 247.8 and 217.1 Bq/m3, for K and IDW, respectively. Through the Moran’s I values obtained, correspondingly equal to 0.56 and 0.61, it was evident that LC mortality was directly associated with locations with high levels of radon, considering a stable population for more than 25 years, suggesting spatial clustering of LC deaths due to indoor radon concentrations.

  2. Lung cancer mortality and radon concentration in a chronically exposed neighborhood in Chihuahua, Mexico: a geospatial analysis.

    Science.gov (United States)

    Hinojosa de la Garza, Octavio R; Sanín, Luz H; Montero Cabrera, María Elena; Serrano Ramirez, Korina Ivette; Martínez Meyer, Enrique; Reyes Cortés, Manuel

    2014-01-01

    This study correlated lung cancer (LC) mortality with statistical data obtained from government public databases. In order to asses a relationship between LC deaths and radon accumulation in dwellings, indoor radon concentrations were measured with passive detectors randomly distributed in Chihuahua City. Kriging (K) and Inverse-Distance Weighting (IDW) spatial interpolations were carried out. Deaths were georeferenced and Moran's I correlation coefficients were calculated. The mean values (over n = 171) of the interpolation of radon concentrations of deceased's dwellings were 247.8 and 217.1 Bq/m(3), for K and IDW, respectively. Through the Moran's I values obtained, correspondingly equal to 0.56 and 0.61, it was evident that LC mortality was directly associated with locations with high levels of radon, considering a stable population for more than 25 years, suggesting spatial clustering of LC deaths due to indoor radon concentrations.

  3. Occurrences of Uranium and Radon-222 in Groundwaters from Various Geological Environments in the Hoengseong Area

    Science.gov (United States)

    Jeong, Chan Ho; Lee, Yu Jin; Lee, Young Cheon; Choi, Hyeon Young; Yang, Jae Ha

    2016-04-01

    Groundwaters in granite, gneiss, and two-mica granite formations, including faults, in the Hoengseong area are examined to determine the relationship between their uranium and radon-222 contents and rock types. The chemical compositions of 38 groundwater samples and four surface water samples collected in the study area were analyzed. Sixteen of the samples showing high uranium and radon-222 contents were repeatedly analyzed. Surface radioactivities were measured at 30 points. The uranium and radon-222 concentrations in the groundwater samples were in the ranges of 0.02-49.3 μg/L and 20-906 Bq/L, respectively. Four samples for uranium and 35 samples for radon had concentrations exceeding the alternative maximum contaminant level of the US EPA. The chemical compositions of groundwaters indicated Ca(Na)-HCO3 and Ca(Na)-NO3(HCO3+Cl) types. The pH values ranged from 5.71 to 8.66. High uranium and radon-222 contents in the groundwaters occurred mainly at the boundary between granite and gneiss, and in the granite area. The occurrence of uranium did not show any distinct relationship to that of radon-222. The radon-222, an inert gas, appeared to be dissolved in the groundwater of the aquifer after wide diffusion along rock fractures, having been derived from the decay of uranium in underground rocks. The results in this study indicate that groundwater of neutral or weakly alkaline pH, under oxidizing conditions and with a high bicarbonate content is favorable for the dissolution of uranium and uranium complexes such as uranyl or uranyl-carbonate. Key word: uranium, radon-222, geological boundary, groundwater, chemical characteristics, surface radioactivity

  4. Persistence of radon-222 flux during monsoon at a geothermal zone in Nepal.

    Science.gov (United States)

    Girault, Frédéric; Koirala, Bharat Prasad; Perrier, Frédéric; Richon, Patrick; Rajaure, Sudhir

    2009-11-01

    The Syabru-Bensi hydrothermal zone, Langtang region (Nepal), is characterized by high radon-222 and CO(2) discharge. Seasonal variations of gas fluxes were studied on a reference transect in a newly discovered gas discharge zone. Radon-222 and CO(2) fluxes were measured with the accumulation chamber technique, coupled with the scintillation flask method for radon. In the reference transect, fluxes reach exceptional mean values, as high as 8700+/-1500 gm(-2)d(-1) for CO(2) and 3400+/-100 x 10(-3) Bq m(-2)s(-1) for radon. Gases fluxes were measured in September 2007 during the monsoon and during the dry winter season, in December 2007 to January 2008 and in December 2008 to January 2009. Contrary to expectations, radon and its carrier gas fluxes were similar during both seasons. The integrated flux along this transect was approximately the same for radon, with a small increase of 11+/-4% during the wet season, whereas it was reduced by 38+/-5% during the monsoon for CO(2). In order to account for the persistence of the high gas emissions during monsoon, watering experiments have been performed at selected radon measurement points. After watering, radon flux decreased within 5 min by a factor of 2-7 depending on the point. Subsequently, it returned to its original value, firstly, by an initial partial recovery within 3-4h, followed by a slow relaxation, lasting around 10h and possibly superimposed by diurnal variations. Monsoon, in this part of the Himalayas, proceeds generally by brutal rainfall events separated by two- or three-day lapses. Thus, the recovery ability shown in the watering experiments accounts for the observed long-term persistence of gas discharge. This persistence is an important asset for long-term monitoring, for example to study possible temporal variations associated with stress accumulation and release.

  5. Comparative study of various techniques for environmental radon, thoron and progeny measurements.

    Science.gov (United States)

    Ramola, R C; Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Gusain, G S; Mishra, Rosaline; Sahoo, S K; Tokonami, S

    2015-11-01

    Long-term average concentrations of radon, thoron and progeny were measured in normal and high background radiation areas in India using different techniques. Radon, thoron and progeny concentrations were measured using Raduet, Pin-Hole dosimeter, deposition-based CR-39 and deposition-based direct radon/thoron progeny sensor (DRPS/DTPS) detector system. All these techniques were used at a same time inside an individual dwelling. Radon concentration was recorded higher than thoron concentration in Garhwal Homes (NBRA) while thoron concentration was found relatively higher in the houses of Chhatarpur area (HBRA) in Odisha, India. The values measured with the CR-39 detector-based technique were found comparable with the values measured with the LR-115 detector-based technique. The comparisons of results using various techniques and their usefulness in radiation measurements are discussed in detail.

  6. Radon emissions related to the granitic Precambrian shield in southern Brazil.

    Science.gov (United States)

    Fianco, Ana C B; Roisenberg, Ari; Bonotto, Daniel M

    2013-01-01

    The equivalent uranium (eU) activity concentration was analysed in selected granite samples at several sites in Porto Alegre, Southern Brazil, to obtain information on the radon ((222)Rn) generation by the aquifer rock matrices. Radon analyses of ground water and soil samples were also performed. Several samples exhibited a dissolved (222)Rn activity concentration exceeding the World Health Organization maximum limit of 100 Bq l(-1). The dissolved radon content in ground waters from the Fractured Precambrian Aquifer System exhibited a direct significant correlation with the eU in the rock matrices, which is a typical result of water-rock interactions. Variation in the soil's porosity was confirmed as an important factor for (222)Rn release, as expected, due to its gaseous nature. Thus, although the calcic-alkaline to alkaline Precambrian granitoid rocks of the study area are important reservoirs for underground resources, they can release high amounts of radon gas into the liquid phase.

  7. Correlative and multivariate analysis of increased radon concentration in underground laboratory.

    Science.gov (United States)

    Maletić, Dimitrije M; Udovičić, Vladimir I; Banjanac, Radomir M; Joković, Dejan R; Dragić, Aleksandar L; Veselinović, Nikola B; Filipović, Jelena

    2014-11-01

    The results of analysis using correlative and multivariate methods, as developed for data analysis in high-energy physics and implemented in the Toolkit for Multivariate Analysis software package, of the relations of the variation of increased radon concentration with climate variables in shallow underground laboratory is presented. Multivariate regression analysis identified a number of multivariate methods which can give a good evaluation of increased radon concentrations based on climate variables. The use of the multivariate regression methods will enable the investigation of the relations of specific climate variable with increased radon concentrations by analysis of regression methods resulting in 'mapped' underlying functional behaviour of radon concentrations depending on a wide spectrum of climate variables. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Search for correlation of radon levels and incidence of salivary gland tumors

    Energy Technology Data Exchange (ETDEWEB)

    Miller, A.S.; Harwick, R.D.; Alfaro-Miranda, M.; Sundararajan, M. (Temple Univ. School of Medicine, Philadelphia, PA (United States))

    1993-01-01

    Studies were undertaken to determine if there is a statistical correlation between randon levels and the incidence of salivary gland tumors because of high levels of radon in Pennsylvania. In Part I of the study, the incidence of minor salivary gland tumors accessioned by Temple University, Emory University, and University of Southern California from 1986 to 1988 were correlated with average radon levels in the three locations with the use of standard statistical analyses. In Part II, the occurrence of malignant salivary gland tumors was obtained for each of the 67 counties in Pennsylvania from 1986 to 1988 and correlated statistically with radon levels and population figures in each of those counties. A statistically significant correlation between radon levels and incidence of salivary gland tumors could not be demonstrated in either case.

  9. A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies

    Directory of Open Access Journals (Sweden)

    Ogoma Sheila B

    2012-12-01

    Full Text Available Abstract Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propose scientific consensus on terminologies and methodologies used for evaluation of product formats that could contain spatial chemical actives, including indoor residual spraying (IRS, long lasting insecticide treated nets (LLINs and insecticide treated materials (ITMs. PubMed, (National Centre for Biotechnology Information (NCBI, U.S. National Library of Medicine, NIH, MEDLINE, LILAC, Cochrane library, IBECS and Armed Forces Pest Management Board Literature Retrieval System search engines were used to identify studies of pyrethroid based coils and emanators with key-words “Mosquito coils” “Mosquito emanators” and “Spatial repellents”. It was concluded that there is need to improve statistical reporting of studies, and reach consensus in the methodologies and terminologies used through standardized testing guidelines. Despite differing evaluation methodologies, data showed that coils and emanators induce mortality, deterrence, repellency as well as reduce the ability of mosquitoes to feed on humans. Available data on efficacy outdoors, dose–response relationships and effective distance of coils and emanators is inadequate for developing a target product profile (TPP, which will be required for such chemicals before optimized implementation can occur for maximum benefits in disease control.

  10. Current state of radon chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Avrorin, V.V.; Krasikova, R.N.; Nefedov, V.D.; Toropova, M.A.

    1982-01-01

    This article summarizes the data available prior to May 1980 on the physical, chemical and radioactive properties of radon. Tables include a list of the known isotopes together with the half-lives, types of emitted radiation and daughter products and a list of the inert gases Rn, Xe, Kr, Ar and Ne together with the hydrate stability, ionization potential, ionic character of bonding, dissociation energy, electronegativity and others. Experimental difficulties of working with radon, such as its short half-life and its fugitive nature, are mentioned. The compound RNF/sub 2/ can be prepared from several different fluorinating reagents such as ClF/sub 3/, KrF/sub 3/, BrF/sub 3/, K/sub 2/NiF/sub 6/ in HF and others. Until now it has not been possible to prepare organic compounds of inert gases using classical techniques. Noble gas compounds may also be prepared via radiochemical techniques. Some applications of radon compounds, such as in decontamination of reactor and mine effluents, are discussed.

  11. Calibration of radon-222 detectors using closed circuit radium-226 sources; Calibracao de detectores de radonio-222 atraves do uso de fontes de radio-222 em circuito fechado

    Energy Technology Data Exchange (ETDEWEB)

    Perna, Allan Felipe Nunes; Paschuk, Sergei Anatolyevich; Correa, Janine Nicolosi; Del Claro, Flavia, E-mail: allan_perna@hotmail.com, E-mail: sergei@utfpr.edu.br, E-mail: janine@utfpr.edu.br, E-mail: flavia_delclaro@yahoo.com.br [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil)

    2012-07-01

    This paper presents the results of the calibration of the Radon-222 detectors used by the Laboratories specializing in measuring natural radiation from this gas. The research was conducted in collaboration between UTFPR, CDTN/CNEN, UFRN and IRD/CNEN. During the calibration the detectors were exposed in isolated chambers with radioactive calibrated sources. The calibration procedure was supported with four instant radon monitors AlphaGUARD (SAPHYMO Co.) responsible for radon activity measurements in the experimental chamber. The calibration procedure resulted an equation that relates the number of tracks found in solid-state detector CR-39 (Track-Etch detector) with the concentration of radon in the atmosphere. Obtained results are compatible with previously performed calibration at the National Institute of Radiological Sciences (NIRS, Japan) using high activity levels of radon in air. Present results of calibration give the possibility to expand the calibration curve of CR-39 for medium and low activity levels of radon. (author)

  12. Radon exposure of the skin: I. Biological effects

    Energy Technology Data Exchange (ETDEWEB)

    Charles, M W [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2007-09-15

    Radon progeny can plate out on skin and give rise to exposure of the superficial epidermis from alpha emitters Po-218 (7.7 MeV, range {approx}66 {mu}m) and Po-214 (6 MeV, range {approx}44 {mu}m). Dose rates from beta/gamma emitters Pb-214 and Bi-214 are low and only predominate at depths in excess of the alpha range. This paper reviews the evidence for a causal link between exposure from radon and its progeny, and deterministic and stochastic biological effects in human skin. Radiation induced skin effects such as ulceration and dermal atrophy, which require irradiation of the dermis, are ruled out for alpha irradiation from radon progeny because the target cells are considerably deeper than the range of alpha particles. They have not been observed in man or animals. Effects such as erythema and acute epidermal necrosis have been observed in a few cases of very high dose alpha particle exposures in man and after acute high dose exposure in animals from low energy beta radiations with similar depth doses to radon progeny. The required skin surface absorbed doses are in excess of 100 Gy. Such effects would require extremely high levels of radon progeny. They would involve quite exceptional circumstances, way outside the normal range of radon exposures in man. There is no definitive identification of the target cells for skin cancer induction in animals or man. The stem cells in the basal layer which maintain the epidermis are the most plausible contenders for target cells. The majority of these cells are near the end of the range of radon progeny alpha particles, even on the thinnest body sites. The nominal depth of these cells, as recommended by the International Commission on Radiological Protection (ICRP), is 70 {mu}m. There is evidence however that some irradiation of the hair follicles and/or the deeper dermis, as well as the inter-follicular epidermis, is also necessary for skin cancer induction. Alpha irradiation of rodent skin that is restricted to the

  13. Domestic Radon Exposure and Risk of Childhood Cancer: A Prospective Census-Based Cohort Study

    Science.gov (United States)

    Hauri, Dimitri; Spycher, Ben; Huss, Anke; Zimmermann, Frank; Grotzer, Michael; von der Weid, Nicolas; Weber, Damien; Spoerri, Adrian; Kuehni, Claudia E.

    2013-01-01

    Background: In contrast with established evidence linking high doses of ionizing radiation with childhood cancer, research on low-dose ionizing radiation and childhood cancer has produced inconsistent results. Objective: We investigated the association between domestic radon exposure and childhood cancers, particularly leukemia and central nervous system (CNS) tumors. Methods: We conducted a nationwide census-based cohort study including all children radon levels were estimated for each individual home address using a model developed and validated based on approximately 45,000 measurements taken throughout Switzerland. Data were analyzed with Cox proportional hazard models adjusted for child age, child sex, birth order, parents’ socioeconomic status, environmental gamma radiation, and period effects. Results: In total, 997 childhood cancer cases were included in the study. Compared with children exposed to a radon concentration below the median (radon exposure is associated with childhood cancer, despite relatively high radon levels in Switzerland. Citation: Hauri D, Spycher B, Huss A, Zimmermann F, Grotzer M, von der Weid N, Weber D, Spoerri A, Kuehni C, Röösli M, for the Swiss National Cohort and the Swiss Paediatric Oncology Group (SPOG). 2013. Domestic radon exposure and risk of childhood cancer: a prospective census-based cohort study. Environ Health Perspect 121:1239–1244; http://dx.doi.org/10.1289/ehp.1306500 PMID:23942326

  14. Find a Radon Test Kit or Measurement and Mitigation Professional

    Science.gov (United States)

    Find a qualified radon service professional to fix or mitigate your home. If you have questions about a radon, you should contact your state radon contact and/or contact one or both of the two privately-run National Radon Proficiency Programs

  15. Systematic radon survey over active volcanoes

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, J.L.; Monnin, M.; Garcia Vindas, J.R. [Centre National de la Recherche Cientifique, Montpellier (France). Lab. GBE; Ricard, L.P.; Staudacher, T. [Observatoire Volcanologique Du Pitou de la Fournaise, La Plaine des Cafres (France)

    1999-08-01

    Data obtained since 1993 on Costa Rica volcanos are presented and radon anomalies recorded before the eruption of the Irazu volcano (December 8, 1994) are discussed. The Piton de la Fournaise volcano is inactive since mid 1992. The influence of the external parameters on the radon behaviour is studied and the type of perturbations induced on short-term measurements are individuate.

  16. Radon Measurements in Schools: An Interim Report.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Radiation Programs.

    Radon-222 is a colorless, odorless, tasteless, radioactive gas that occurs naturally in soil, rocks, underground water, and air. The United States Environmental Protection Agency (EPA) and other scientific organizations have identified an increased risk of lung cancer associated with exposure to elevated levels of radon in homes. Schools in many…

  17. Domestic Radon and Childhood Cancer in Denmark

    DEFF Research Database (Denmark)

    Raaschou-Nielsen, Ole; Andersen, Claus Erik; Andersen, Helle P.

    2008-01-01

    Background: Higher incidence rates of childhood cancer and particularly leukemia have been observed in regions with higher radon levels, but case-control studies have given inconsistent results. We tested the hypothesis that domestic radon exposure increases the risk for childhood cancer. Methods...

  18. Removal of Radon from Household Water.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC. Office of Research and Development.

    By far, the greatest risk to health from radon occurs when the gas enters the house from underlying soil and is inhaled. The U.S. Environmental Protection Agency (EPA) is studying ways to reduce radon in houses, including methods to remove the gas from water to prevent its release in houses when the water is used. While this research has not…

  19. Radon Risk Communication Strategies: A Regional Story.

    Science.gov (United States)

    Cheng, Winnie

    2016-01-01

    Risk communication on the health effects of radon encounters many challenges and requires a variety of risk communication strategies and approaches. The concern over radon exposure and its health effects may vary according to people's level of knowledge and receptivity. Homeowners in radon-prone areas are usually more informed and have greater concern over those not living in radon-prone areas. The latter group is often found to be resistant to testing. In British Columbia as well as many other parts of the country, some homes have been lying outside of the radon-prone areas have radon levels above the Canadian guideline, which is the reason Health Canada recommends that all homes should be tested. Over the last five years, the Environment Health Program (EHP) of Health Canada in the British Columbia region has been using a variety of different approaches in their radon risk communications through social media, workshops, webinars, public forums, poster contests, radon distribution maps, public inquiries, tradeshows and conference events, and partnership with different jurisdictions and nongovernmental organizations. The valuable lessons learned from these approaches are discussed in this special report.

  20. Radon Measurement in Schools. Revised Edition.

    Science.gov (United States)

    Environmental Protection Agency, Washington, DC.

    The Environmental Protection Agency (EPA) and other major national and international scientific organizations have concluded that radon is a human carcinogen and a serious environmental health problem. The EPA has conducted extensive research on the presence and measurement of radon in schools. This report provides school administrators and…

  1. Radon progeny monitoring at the Eastern North Atlantic (ENA), Graciosa Island ARM facility and a potential earthquake precursory signal

    Science.gov (United States)

    Barbosa, Susana; Mendes, Virgilio B.; Azevedo, Eduardo B.

    2016-04-01

    Radon has been considered a promising earthquake precursor, the main rationale being an expected increase in radon exhalation in soil and rocks due to stress associated with the preparatory stages of an earthquake. However, the precursory nature of radon is far from being convincingly demonstrated so far. A major hindrance is the many meteorological and geophysical factors diving radon temporal variability, including the geophysical parameters influencing its emanation (grain size, moisture content, temperature), as well as the meteorological factors (atmospheric pressure, moisture, temperature, winds) influencing its mobility. Despite the challenges, radon remains one of the strongest candidates as a potential earthquake precursor, and it is of crucial importance to investigate the many factors driving its variability and its potential association with seismic events. Continuous monitoring of radon progeny is performed at the Eastern North Atlantic (ENA) facility located in the Graciosa island (Azores, 39N; 28W), a fixed site of the Atmospheric Radiation Measurement programme (ARM), established and supported by the Department of Energy (DOE) of the United States of America with the collaboration of the local government and University of the Azores. The Azores archipelago is associated with a complex geodynamic setting on the Azores triple junction where the American, Eurasian and African litospheric plates meet, resulting in significant seismic and volcanic activity. A considerable advantage of the monitoring site is the availability of a comprehensive dataset of concurrent meteorological observations performed at the ENA facility and freely available from the ARM data archive, enabling a detailed analysis of the environmental factors influencing the temporal variability of radon's progeny. Gamma radiation is being measured continuously every 15 minutes since May 2015. The time series of gamma radiation counts is dominated by sharp peaks lasting a few hours and

  2. Indoor radon survey in the Vojvodina region

    Energy Technology Data Exchange (ETDEWEB)

    Forkapic, S.; Todorovic, N.; Bikit, I.; Mrda, D.; Slivka, J.; Veskovic, M. [Department of Physics, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovica 4, 21000 Novi Sad (Serbia)

    2010-07-01

    The results of an indoor radon survey in the Vojvodina region (Serbia) are presented. Long-term average radon measurements in an existing building can be measured relatively simply and inexpensively using a passive device, such as an alpha track detector. Houses in the suburbs were chosen as the target locations of the present investigations. Indoor radon concentrations were measured with CR-39 alpha track detectors at {approx}1000 locations in Vojvodina during the winter period. Effect of floor level, space under the rooms, boarding and the heating system on radon accumulation are discussed in this paper. For the dwellings typical of such regions, we measure a mean annual radon activity concentration of 112 Bq/m{sup 3} (747 measurements using the alpha track detector CR-39). (authors)

  3. Indoor radon risk potential of Hawaii

    Science.gov (United States)

    Reimer, G.M.; Szarzi, S.L.

    2005-01-01

    A comprehensive evaluation of radon risk potential in the State of Hawaii indicates that the potential for Hawaii is low. Using a combination of factors including geology, soils, source-rock type, soil-gas radon concentrations, and indoor measurements throughout the state, a general model was developed that permits prediction for various regions in Hawaii. For the nearly 3,100 counties in the coterminous U.S., National Uranium Resource Evaluation (NURE) aerorad data was the primary input factor. However, NURE aerorad data was not collected in Hawaii, therefore, this study used geology and soil type as the primary and secondary components of potential prediction. Although the radon potential of some Hawaiian soils suggests moderate risk, most houses are built above ground level and the radon soil potential is effectively decoupled from the house. Only underground facilities or those with closed or recirculating ventilation systems might have elevated radon potential. ?? 2005 Akade??miai Kiado??.

  4. Radon in houses and soil of Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Radolic, V.; Vukovic, B.; Stanic, D.; Miklavcic, I.; Planinic, J. [Osijek Univ., Dept. of Physics (Croatia)

    2006-07-01

    Long-term indoor radon measurements in thousand Croatian homes, randomly selected, were performed by the LR-115 track etch detectors during a year 2003/2004. The obtained values of arithmetic means of radon concentrations in 20 Croatian counties were in range from 33 to 198 Bq/m{sup 3}, while the arithmetic and geometric means for Croatia were 68 and 50 Bq/m{sup 3}, respectively. Indoor radon concentrations follow log-normal distribution and the percentage of dwellings with concentrations above 400 Bq/m{sup 3} was 1.8 %. Radon concentrations in soil gas, at depth of 0.8 m, were measured by 'Alphaguard' measuring system. Association between levels of indoor and soil radon was investigated. (authors)

  5. A complete low cost radon detection system.

    Science.gov (United States)

    Bayrak, A; Barlas, E; Emirhan, E; Kutlu, Ç; Ozben, C S

    2013-08-01

    Monitoring the (222)Rn activity through the 1200 km long Northern Anatolian fault line, for the purpose of earthquake precursory, requires large number of cost effective radon detectors. We have designed, produced and successfully tested a low cost radon detection system (a radon monitor). In the detector circuit of this monitor, First Sensor PS100-7-CER-2 windowless PIN photodiode and a custom made transempedence/shaping amplifier were used. In order to collect the naturally ionized radon progeny to the surface of the PIN photodiode, a potential of 3500 V was applied between the conductive hemi-spherical shell and the PIN photodiode. In addition to the count rate of the radon progeny, absolute pressure, humidity and temperature were logged during the measurements. A GSM modem was integrated to the system for transferring the measurements from the remote locations to the data process center.

  6. Assessment of indoor radon doses received by the students in the Azad Kashmir schools, Pakistan.

    Science.gov (United States)

    Rafique, Muhammad; Rahman, S U; Rahman, Said; Matiullah; Shahzad, M Ikram; Ahmed, Navid; Iqbal, Javid; Ahmed, Basharat; Ahmed, Tanveer; Akhtar, Nadeem

    2010-12-01

    Several epidemiological studies conducted on thousands of underground miners suggest that long- term exposure to high radon concentration can increase the risk of lung cancer. Keeping in view the importance of the subject, numerous studies throughout the world have been carried out to measure indoor radon concentration and its resulting doses at occupational and non-occupational sites. The purpose of the current study was to measure indoor radon concentration and its resulting doses received by the students of Azad Kashmir government schools. For this purpose, CR-39 radon detectors were installed in 80 carefully selected schools. The detectors were placed at a height of 3-5 ft. (depending upon average height of students in particular class) from the ground. After exposure of 90 d detectors were etched for 9 h in 6 M NaOH at 70°C and the observed track densities were related to radon concentrations. The measured indoor radon concentration ranged from 22 ± 9 to 228 ± 3 Bq m(-3) with a mean value of 78 ± 5 Bq m(-3). Based on the measured indoor radon data, the annual effective doses were found to vary from 0.55 ± 0.04 to 0.71 ± 0.03 mSv y(-1). The overall mean effective dose for the studied area was found to be 0.63 ± 0.04 mSv y(-1). Reported values for radon concentrations and corresponding doses are lower than ICRP recommended limits for workplaces.

  7. The distribution of indoor radon in Transylvania (Romania) - influence of the natural and anthropogenic factors

    Science.gov (United States)

    Cucos Dinu, Alexandra; Baciu, Calin; Dicu, Tiberius; Papp, Botond; Moldovan, Mircea; Bety Burghele, Denissa; Tenter, Ancuta; Szacsvai, Kinga

    2017-04-01

    (residential, soil, water) was observed, both as individual values, average values over the grid or county level. The highest concentrations of indoor radon were found in Bihor, Mures, Brasov, and Cluj. In these regions further investigation is needed on the factors influencing the accumulation of radon in high concentrations in indoor air, such as soil type and geology, ventilation, or constructive and architectural features. Acknowledgements: The research is supported by the project ID P_37_229, Contract No. 22/01.09.2016, with the title „Smart Systems for Public Safety through Control and Mitigation of Residential Radon linked with Energy Efficiency Optimization of Buildings in Romanian Major Urban Agglomerations SMART-RAD-EN" of the POC Programme.

  8. Least-squares reverse time migration with local Radon-based preconditioning

    KAUST Repository

    Dutta, Gaurav

    2017-03-08

    Least-squares migration (LSM) can produce images with better balanced amplitudes and fewer artifacts than standard migration. The conventional objective function used for LSM minimizes the L2-norm of the data residual between the predicted and the observed data. However, for field-data applications in which the recorded data are noisy and undersampled, the conventional formulation of LSM fails to provide the desired uplift in the quality of the inverted image. We have developed a leastsquares reverse time migration (LSRTM) method using local Radon-based preconditioning to overcome the low signal-tonoise ratio (S/N) problem of noisy or severely undersampled data. A high-resolution local Radon transform of the reflectivity is used, and sparseness constraints are imposed on the inverted reflectivity in the local Radon domain. The sparseness constraint is that the inverted reflectivity is sparse in the Radon domain and each location of the subsurface is represented by a limited number of geologic dips. The forward and the inverse mapping of the reflectivity to the local Radon domain and vice versa is done through 3D Fourier-based discrete Radon transform operators. The weights for the preconditioning are chosen to be varying locally based on the relative amplitudes of the local dips or assigned using quantile measures. Numerical tests on synthetic and field data validate the effectiveness of our approach in producing images with good S/N and fewer aliasing artifacts when compared with standard RTM or standard LSRTM.

  9. Tracing and quantifying groundwater inflow into lakes using a simple method for radon-222 analysis

    Directory of Open Access Journals (Sweden)

    T. Kluge

    2007-09-01

    Full Text Available Due to its high activities in groundwater, the radionuclide 222Rn is a sensitive natural tracer to detect and quantify groundwater inflow into lakes, provided the comparatively low activities in the lakes can be measured accurately. Here we present a simple method for radon measurements in the low-level range down to 3 Bq m−3, appropriate for groundwater-influenced lakes, together with a concept to derive inflow rates from the radon budget in lakes. The analytical method is based on a commercially available radon detector and combines the advantages of established procedures with regard to efficient sampling and sensitive analysis. Large volume (12 l water samples are taken in the field and analyzed in the laboratory by equilibration with a closed air loop and alpha spectrometry of radon in the gas phase. After successful laboratory tests, the method has been applied to a small dredging lake without surface in- or outflow in order to estimate the groundwater contribution to the hydrological budget. The inflow rate calculated from a 222Rn balance for the lake is around 530 m³ per day, which is comparable to the results of previous studies. In addition to the inflow rate, the vertical and horizontal radon distribution in the lake provides information on the spatial distribution of groundwater inflow to the lake. The simple measurement and sampling technique encourages further use of radon to examine groundwater-lake water interaction.

  10. Radon concentrations in abandoned mines, Cumbria, UK: safety implications for industrial archaeologists

    Directory of Open Access Journals (Sweden)

    G. Gillmore

    2011-05-01

    Full Text Available This paper presents a number of surveys performed in a geographical area of the UK, part of which until recently was considered low radon risk. The Cumbrian region was identified by the Building Research Establishment (BRE in its 1999 guide as an area without a significant radon problem in the built environment. The geology of the region, which includes the Northern Pennine Orefield is varied, but consists of granites, andesites, tuffs, carbonates, sandstones and shales. Mineralisation has taken place (mostly lead and copper ores primarily along fault and fracture zones, one example being Copper Valley, northwest of Coniston village. This work quantifies the risk of exposure to radon in a number of abandoned mine environments. High radon levels, up to 28 589 Bq m−3, have been measured in parts of one mine. This study demonstrates that industrial archaeologists (such as the Cumbrian Amenity Trust Mining History Society or CATMHS members and explorers of abandoned mines can be at risk from radon exposure and it proposes a management scheme to allow industrial archaeologists to continue exploration whilst minimising the risk to health from radon.

  11. Soil radon as a possible earthquake precursor: Preliminary results from Ileia (Greece)

    Science.gov (United States)

    Petraki, Ermioni; Nikolopoulos, Dimitrios; Louizi, Anna; Zisos, Athanasios

    2010-05-01

    Radon (222Rn) is a naturally occurring radioactive gas which is directly produced by the decay of the 238U series. It is significant for the studies of Earth, in hydrogeology and atmosphere. Radon is used as a trace gas due to the long half-life (3.82-days) which allows migration at long distances. In addition, it is an alpha emitter, fact which enables detection of low levels of radon. Anomalies of radon impending earthquakes of a variety of magnitudes have been observed in soil gas, ground- and thermal-waters and in underground tunnels. Increasing is the scientific interest in this field during the last two years. However, the majority of the published papers refer to data of rather long time intervals between sequential measurements (~2-4 weeks).On the other hand, it is justified, both on laboratory and geophysical scale, that when a heterogeneous material is strained acoustic and electromagnetic (EM) emissions occur in a wide frequency spectrum, ranging from very low to very high frequencies. These emissions are considered as precursors of general fracture. In the search of soil radon as a possible earthquake precursor, a station for quick and continuous monitoring of soil radon has been installed in a very active tectonic site in Greece (Ileia, Peloponnese, SW Greece). The monitoring site is Kardamas Ileias, located 3 km south from Amaliada which is the second highly populated city. The instrumental and felt seismicity of Ileia is dominated by extensional active seismicity structures (e.g. Alfeios, Neda, Melpeia, Kiparissia-Aetos) and has shown more than 600 earthquakes of magnitude greater than 4.0 R in the last 100 years. Two earthquakes were very destructive (5.8 R on 26/3/93 and 6.8 R on 8/6/08 respectively). The station consists of a high precision active instrument (Alpha Guard-AG, Genitron Ltd.), equipped with an appropriate unit designed for pumping and measurement of radon in soil gas (Soil gas Unit, Genitron Ltd.). Soil radon is continuously pumped

  12. Using radon-222 to study coastal groundwater/surface-water interaction in the Crau coastal aquifer (southeastern France)

    Science.gov (United States)

    Mayer, Adriano; Nguyen, Bach Thao; Banton, Olivier

    2016-11-01

    Radon has been used to determine groundwater velocity and groundwater discharge into wetlands at the southern downstream boundary of the Crau aquifer, southeastern France. This aquifer constitutes an important high-quality freshwater resource exploited for agriculture, industry and human consumption. An increase in salinity occurs close to the sea, highlighting the need to investigate the water balance and groundwater behavior. Darcy velocity was estimated using radon activities in well waters according to the Hamada "single-well method" (involving comparison with radon in groundwater in the aquifer itself). Measurements done at three depths (7, 15 and 21 m) provided velocity ranging from a few mm/day to more than 20 cm/day, with highest velocities observed at the 15-m depth. Resulting hydraulic conductivities agree with the known geology. Waters showing high radon activity and high salinity were found near the presumed shoreline at 3,000 years BP, highlighting the presence of ancient saltwater. Radon activity has also been measured in canals, rivers and ponds, to trace groundwater discharges and evaluate water balance. A model of the radon spatial evolution explains the observed radon activities. Groundwater discharge to surface water is low in pond waters (4 % of total inputs) but significant in canals (55 l/m2/day).

  13. Risk assessment of exposure to radon decay products

    Energy Technology Data Exchange (ETDEWEB)

    Monchaux, G

    1999-07-01

    HRTM have been developed. These models form the basis of what would be required to calculate the equivalent dose to each of the rats used in the animal experiments. The main objective for the Human Studies Group was to conduct inhalation studies with human volunteers under well-defined conditions, to obtain a better experimental data base for dose calculations for inhaled radon progeny. The specific properties of the airborne radon progeny were characterised by two different modes to be studied, the unattached fraction, which has a size of about 1 nm, and the attached fraction where ambient aerosol particles are associated to radon progeny atoms. The studies included deposition patterns of the unattached fraction and the dependence of deposition on age and gender, the transfer or inhaled radon progeny to blood and the comparison of total deposition of radon progeny for adults and children in the domestic environment. In particular, the absorption half-time of unattached radon progeny from the respiratory tract to the blood was found to be shorter than the ICRP default value of 10 hours. In the Animal Studies Group, new series of experiments were carried out to investigate the influence of exposure-rate on lung cancer induction in rats at relatively low cumulative exposures. The preliminary results indicate that at relatively low cumulative exposures comparable to lifetime exposures in high-radon houses or current underground mining exposures, the risk of lung cancer in rats decreases with decreasing PAEC, i.e., exposure-rates. These data suggest that in terms of risk of induction of lung cancer, there is a complex interplay between cumulative exposure and exposure rate, resulting in an optimal exposure rate at a given exposure level. A positive dose rate response was seen for proliferating epithelial cells at relatively high exposure levels. The response of proliferating epithelial cells was found to depend on dose rate at higher doses, whereas at lower cumulative

  14. 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)

  15. Radon, Smoking, and Lung Cancer: The Need to Refocus Radon Control Policy

    Science.gov (United States)

    Mendez, David; Philbert, Martin A.

    2013-01-01

    Exposure to radon is the second leading cause of lung cancer, and the risk is significantly higher for smokers than for nonsmokers. More than 85% of radon-induced lung cancer deaths are among smokers. The most powerful approach for reducing the public health burden of radon is shaped by 2 overarching principles: public communication efforts that promote residential radon testing and remediation will be the most cost effective if they are primarily directed at current and former smokers; and focusing on smoking prevention and cessation is the optimal strategy for reducing radon-induced lung cancer in terms of both public health gains and economic efficiency. Tobacco control policy is the most promising route to the public health goals of radon control policy. PMID:23327258

  16. A Rapid Method for Radon Determination

    Energy Technology Data Exchange (ETDEWEB)

    Enkhbat, N.; Shin, S. G.; Key, Y. U.; Cho, M. H. [POSTECH, Pohang (Korea, Republic of); Norov, N. [National University of Mongolia, Ulaanbaatar (Mongolia); Kim, G. [Kungpook National University, Daegu (Korea, Republic of); Namkung, W.; Lee, H. S. [Pohang Accelerator Laboratory, Pohang (Korea, Republic of)

    2015-05-15

    Research carried out in last decades has shown that more than 70% of a total annual radioactive dose received by people originates from natural sources of ionizing radiation, whereby 40% is due to inhalation and ingestion of natural radioactive gas radon {sup 222}Rn and its progeny. Radon has 3.5 days of half-life. However, its progeny is dangerous than Radon in the view of radiation protection. Radon measurement is commonly used in controlling radon concentration in underground mine, closed room and in forecasting earthquake. Radon gas emission rate in the immediate opening of the west ventilation shaft depends on the operation of the ventilation system, duration of ventilation system operation, and the air flow rate through the underground development. Specific activity of radon progeny in air (RaA (Po-218), RaB (Pb-214) and RaC (Bi-214)) and Ra-222 in radioactive equilibrium was calculated by formula 1 and 2, respectively. We include result of measurement carried out in the air around a mining. In Fig.2 shown that the distribution of Po-218, Pb-214, Bi-214 and Ra-222 isotopes releasing from west ventilation shaft in Gurvanbulag underground uranium mine in the eastern part of Mongolia.

  17. Radiological and material characterization of high volume fly ash concrete.

    Science.gov (United States)

    Ignjatović, I; Sas, Z; Dragaš, J; Somlai, J; Kovács, T

    2017-03-01

    The main goal of research presented in this paper was the material and radiological characterization of high volume fly ash concrete (HVFAC) in terms of determination of natural radionuclide content and radon emanation and exhalation coefficients. All concrete samples were made with a fly ash content between 50% and 70% of the total amount of cementitious materials from one coal burning power plant in Serbia. Physical (fresh and hardened concrete density) and mechanical properties (compressive strength, splitting tensile strength and modulus of elasticity) of concrete were tested. The radionuclide content ((226)Ra, (232)Th and (40)K) and radon massic exhalation of HVFAC samples were determined using gamma spectrometry. Determination of massic exhalation rates of HVFAC and its components using radon accumulation chamber techniques combined with a radon monitor was performed. The results show a beneficial effect of pozzolanic activity since the increase in fly ash content resulted in an increase in compressive strength of HVFAC by approximately 20% for the same mass of cement used in the mixtures. On the basis of the obtained radionuclide content of concrete components the I -indices of different HVFAC samples were calculated and compared with measured values (0.27-0.32), which were significantly below the recommended 1.0 index value. The prediction was relatively close to the measured values as the ratio between the calculated and measured I-index ranged between 0.89 and 1.14. Collected results of mechanical and radiological properties and performed calculations clearly prove that all 10 designed concretes with a certain type of fly ash are suitable for structural and non-structural applications both from a material and radiological point of view. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. A study on the correlation between soil radon potential and average indoor radon potential in Canadian cities.

    Science.gov (United States)

    Chen, Jing; Ford, Ken L

    2017-01-01

    Exposure to indoor radon is identified as the main source of natural radiation exposure to the population. Since radon in homes originates mainly from soil gas radon, it is of public interest to study the correlation between radon in soil and radon indoors in different geographic locations. From 2007 to 2010, a total of 1070 sites were surveyed for soil gas radon and soil permeability. Among the sites surveyed, 430 sites were in 14 cities where indoor radon information is available from residential radon and thoron surveys conducted in recent years. It is observed that indoor radon potential (percentage of homes above 200 Bq m(-3); range from 1.5% to 42%) correlates reasonably well with soil radon potential (SRP: an index proportional to soil gas radon concentration and soil permeability; average SRP ranged from 8 to 26). In five cities where in-situ soil permeability was measured at more than 20 sites, a strong correlation (R(2) = 0.68 for linear regression and R(2) = 0.81 for non-linear regression) was observed between indoor radon potential and soil radon potential. This summary report shows that soil gas radon measurement is a practical and useful predictor of indoor radon potential in a geographic area, and may be useful for making decisions around prioritizing activities to manage population exposure and future land-use planning. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  19. Ingredients for a Dutch radon action plan, based on a national survey in more than 2500 dwellings.

    Science.gov (United States)

    Smetsers, R C G M Ronald; Blaauboer, R O Roelf; Dekkers, S A J Fieke

    2016-12-01

    A new Euratom directive demands that Member States establish a national action plan for indoor radon. Important requirements are a national reference level for the radon concentration in dwellings, actions to identify dwellings with radon concentrations that might exceed this reference level and the encouragement of appropriate measures to reduce the radon concentrations in dwellings where these are high. This paper provides ingredients and recommendations for a national action plan for radon in dwellings, applicable to the Netherlands. The approach presented here, which may serve as a model for other countries or regions with a comparatively favourable indoor radon situation, is based on the analysis of radon data from a national survey in more than 2500 Dutch dwellings, built since 1930. The annual average activity concentration of radon in dwellings in the Netherlands equals 15.6 ± 0.3 Bq m(-3). The 50th and 95th percentiles were found to be 12.2 and 38.0 Bq m(-3), respectively. In 0.4 per cent of the dwellings we found values above 100 Bq m(-3). Radon concentrations showed correlations with type of dwelling, year of construction, ventilation system, soil type and smoking behaviour of inhabitants. The survey data suggest that it is feasible for the Netherlands to adopt a national reference level for radon in dwellings of 100 Bq m(-3), in line with recommendations by WHO and ICRP. We were able to predict dwellings with a moderate probability for radon concentrations above 100 Bq m(-3) by applying a combination of three selection criteria: location, type of dwelling and manner of ventilation. Of the existing 6.2 million dwellings in the Netherlands (built since 1930), approximately 23-24 thousand are suspected to exceed this level. Some 80% of these are found in the group of naturally ventilated single-family dwellings in either the southern part of Limburg (approx. 13 thousand) or the Meuse-Rhine-Waal river delta (approx. six thousand). This selected

  20. Temperature calibration of Pico-Rad detectors for radon measurement.

    Science.gov (United States)

    Bem, H; Bem, E M; Chruścielewski, W; Skalski, H

    2000-01-01

    A simple mathematical equation linking the activity of adsorbed radon in the vials to the time and temperature of its exposure is discussed. The calibration coefficient--Ks, defined as activity measured in cpm after saturation time, corresponding to radon air concentration of 1 Bq m-3, was determined for four temperatures: 284, 291, 294 and 298 K. A linear relationship of ln Ks values versus T-1 was found. The relatively high difference in Ks values: 2.12 and 1.24 cpm/Bq m-3 for the temperatures of 284 and 298 K, respectively, was observed. It indicates that temperature fluctuations during Pico-Rad vial exposure may lead to erroneous results if the constant average temperature of exposure is introduced into a commonly used computer programme for calculating Rn concentration.

  1. Temperature calibration of PICO-RAD detectors for radon measurement

    Energy Technology Data Exchange (ETDEWEB)

    Bem, H.; Bem, E.M.; Chruscielewski, W.; Skalski, H. [Politechnika Lodzka, Lodz (Poland)

    1996-10-01

    A simple mathematical equation linking the activity of adsorbed radon in the vials to the time of its exposure has been discussed. The calibration coefficient K{sub s}, defined as a measured activity in cpm after a saturation time, corresponding to a radon air concentration of 1 Bq m{sup -3} has been determined for four temperatures: 284, 291, 294 and 298 K. A linear relationship of ln K{sub s} values versus T{sup -1} has been found. The relatively high difference in K{sub s} values: 2.12 and 1.24 cpm/Bq m{sup 3} for the temperatures of 284 and 298 K, respectively, was observed. It indicates that temperature fluctuations during Pico-Rad vial exposure may lead to erroneous results if the constant average temperature of exposure is introduced into a commonly used computer program for calculating Rn concentration. (author). 6 refs, 4 figs.

  2. Radon in the indoor of habitable and workable zones in the Estado de Mexico; Radon en el interior de zonas habitacionales y laborables del Estado de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Segovia, N.; Gaso, M.I.; Ponciano, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2003-07-01

    The levels of the radon concentration and of suspended particles in the air of the indoor house-room and of laboratories, like part of a study related with the impact of the components of the tobacco smoke in the health of the active and passive smokers. The measures of the radon concentration were carried out with Honeywell A9000A systems and the fluctuations in the concentration and particle size they were determined with a Personal Measurer for the Data Acquisition of Particles in Real Time. The average value of the radon concentration inside the house-room was of 40 Bq m{sup -3}, observing frequently radon peaks superior to 148 Bq m{sup -3}. In the offices and laboratories, especially in those with little ventilation, the radon gas concentration showed superior values to the internationally established limits. The average value in 24 hours, of the particles (PM{sub 10}) inside the houses of smokers it was of 0. 751 {+-} 0.420 mg m{sup -3}, being reached concentrations so high as 1. 6 mg m{sup -3}, which is an order of superior magnitude to the maximum permissible limit of PM{sub 10} (0.150 mg m{sup -3}), settled down by the Mexican Legislation. (Author)

  3. Determination of concentration of radon, volatile organic compounds (VOC) and water chemistry in springs near to Popocatepetl volcano; Determinacion de la concentracion de radon, VOCs y Quimica del agua en manantiales cercanos al volcan Popocatepetl

    Energy Technology Data Exchange (ETDEWEB)

    Pena, P.; Segovia, N.; Lopez M, B.E.; Cisniega, G. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Valdes, C.; Armienta, M.A.; Mena, M. [Instituto de Geofisica, UNAM, 04510 Mexico D.F. (Mexico)

    2004-07-01

    Popocatepetl volcano is a high-risk active volcano in Central Mexico where the highest population density in the country is settled. Radon in the soil and groundwater together with water chemistry from samples of nearby springs is analysed as a function of the 2002-2003 volcanic activity. Soil radon indicated fluctuations related both the meteorological parameters and sporadic explosive events. Groundwater radon showed essentially differences in concentration due to the specific characteristics of the studied springs. Water chemistry showed stability along the monitoring period indicating also differences between springs. No anthropogenic pollution from volatile organic compounds was observed. (Author)

  4. Soil radon levels across the Amer fault

    Energy Technology Data Exchange (ETDEWEB)

    Font, Ll. [Grup de Fisica de les Radiacions, Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)], E-mail: lluis.font@uab.cat; Baixeras, C.; Moreno, V. [Grup de Fisica de les Radiacions, Edifici Cc, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Bach, J. [Unitat de Geodinamica externa, Departament de Geologia, Edifici Cs, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)

    2008-08-15

    Soil radon levels have been measured across the Amer fault, which is located near the volcanic region of La Garrotxa, Spain. Both passive (LR-115, time-integrating) and active (Clipperton II, time-resolved) detectors have been used in a survey in which 27 measurement points were selected in five lines perpendicular to the Amer fault in the village area of Amer. The averaged results show an influence of the distance to the fault on the mean soil radon values. The dynamic results show a very clear seasonal effect on the soil radon levels. The results obtained support the hypothesis that the fault is still active.

  5. Risks related to exposure to radon

    Directory of Open Access Journals (Sweden)

    Juan Miguel Barros Dios

    2010-12-01

    Full Text Available They discuss the different scientific evidence that radon and its short half-life descendants are responsible for the appearance of a considerable number of lung cancers among the exposed population in homes and public buildings (occupational exposure. It also draws a small glimpse at the road traveled by this knowledge and acceptance difficult administrations in many countries and, in particular, of Spain, as well as the various investigations that the team do Galego Radon and Radon Laboratory from Galicia, the area of Public Health, University of Santiago de Compostela (USC, are contributing to scientific knowledge. Finally, they appreciate the few legislative initiatives on the problem in Spain.

  6. Indoor radon concentration forecasting in South Tyrol.

    Science.gov (United States)

    Verdi, L; Weber, A; Stoppa, G

    2004-01-01

    In this paper a modern statistical technique of multivariate analysis is applied to an indoor radon concentration data base. Several parameters are more or less significant in determining the radon concentration inside a building. The elaboration of the information available on South Tyrol makes it possible both to identify the statistically significant variables and to build up a statistical model that allows us to forecast the radon concentration in dwellings, when the values of the same variables involved are given. The results confirm the complexity of the phenomenon.

  7. Radon - kilder og måling

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Wraber, Ida Kristina

    Når man skal vurdere en bygnings indeklima er det vigtigt at have viden om radonindholdet. Denne viden får man ved måling, da radon hverken kan ses, lugtes, høres, smages eller føles. Denne anvisning redegør for radons oprindelse og indvirkning på menneskers sundhed. Anvisningen beskriver metoder...... til måling og analyse af radonindholdet i en bygnings indeluft. Læseren får indsigt i, hvordan man relativt let med standardiserede metoder kan eftervise, om en bygning opfylder bygningsreglementets krav til radon i indeluften. Anvisningen henvender sig til bygningsejere, bygherrer, projekterende og...

  8. Coprecipitation of radon oxide with cesium fluoroxenate

    Energy Technology Data Exchange (ETDEWEB)

    Avrorin, V.V.; Krasikova, R.N.; Nefedov, V.D.; Toropova, M.A.

    1986-03-01

    This paper presents a study of the processes of coprecipitation of radon oxide with cesium fluoroxenate in aqueous solutions. It has been shown that the reason for the coprecipitation in the case at hand is the occurrence of a process of isomorphous cocrystallization. The results obtained are examined as a confirmation of the suggestion that the hydrolysis product of the radon fluoride which is formed on thermal initiation of reaction in the rn-F2-BrF5-NaF system is radon trioxide, Rno3.

  9. Soil radon and electromagnetic anomalies before the Ileia(Greece) M6.8 earthquake

    Science.gov (United States)

    Nikolopoulos, D.; Vogiannis, E.; Louizi, A.; Zisos, A.

    2009-04-01

    Radon (222Rn) is a radioactive gas generated by the decay of the naturally occurring 238U series. It is considered very important from radiological point of view, since it accounts for more than half of the natural exposure of the general public. Radon has been used as trace gas in several studies of Earth, hydrogeology and atmosphere, due to its 3.82-day half-life (which allows migration at long distances) and its alpha decay (which enables low level of detection). It has been accounted in the search of earthquake precursors, volcanic processes, fluid circulation in karstic sources and in the study of natural ventilation of underground cavities. Radon anomalies impending great earthquakes have been observed in groundwater, thermal waters soil gas and in underground tunnels. Ileia is a very active tectonic site located in SW Greece, dominated by extensional active seismicity structures (e.g. Alfeios, Neda, Melpeia, Kiparissia-Aetos). Its instrumental and felt seismicity is very high, with more than 600 earthquakes of magnitude greater than 4.0 R in the last 100 years two of which occurred during the last 15 years and were very destructive (5.8 R on 26/3/93 and 6.8 R on 8/6/08 respectively). Hence, it is an area benefiting from the installation of a geophysical monitoring station, where radon exhalation associated with the accumulation or release of tectonic strain can be studied. In the aforementioned consensus, a station for the surveillance of soil radon has been installed in Kardamas Ileias, 3 km south from Amaliada which is the second highly populated city. The station consists of a high precision (calibration certified) active instrument (Alpha Guard-AG, Genitron Ltd.), equipped with an appropriate unit designed for pumping and measurement of radon in soil gas (Soil gas Unit, Genitron Ltd.). Soil radon is driven into AG via a 1-m probe (to minimize meteorological influences) and a 25-m radon proof 25-mm tube (to avoid simultaneous measurement of soil 220Rn

  10. DETERMINATION OF RADIUM AND RADON CONCENTRATIONS IN SOME ROCK SAMPLES

    OpenAIRE

    BAYKARA, Oktay

    2006-01-01

    The concentrations of radium (226Ra), radon (222Rn) and radon exhalation rate in nine rock samples have been determined using solid-state nuclear track detectors (CR-39). The measured maximum values of radium, radon and radon exhalation rate in rock samples were found to be 24.62 Bq/kg, 4911.32 Bq/m3 and 4,86 Bqm-2h-1, respectively. Linear correlation was observed among radon concentration, radon exhalation and radium concentration. The linear correlation coefficient between radium content an...

  11. Thorough investigations on indoor radon in Baita radon-prone area (Romania)

    Energy Technology Data Exchange (ETDEWEB)

    Cucos, Alexandra; Cosma, Constantin [Faculty of Environmental Science and Engineering, ' Babes-Bolyai' University, Fantanele No. 30, 400294, Cluj-Napoca (Romania); Dicu, Tiberius, E-mail: tiberius.dicu@ubbcluj.ro [Faculty of Environmental Science and Engineering, ' Babes-Bolyai' University, Fantanele No. 30, 400294, Cluj-Napoca (Romania); Begy, Robert; Moldovan, Mircea; Papp, Botond; Nita, Dan; Burghele, Bety [Faculty of Environmental Science and Engineering, ' Babes-Bolyai' University, Fantanele No. 30, 400294, Cluj-Napoca (Romania); Sainz, Carlos [Faculty of Environmental Science and Engineering, ' Babes-Bolyai' University, Fantanele No. 30, 400294, Cluj-Napoca (Romania); Department of Medical Physics, Faculty of Medicine, University of Cantabria, c/Herrera Oria s/n., 39011, Santander (Spain)

    2012-08-01

    A comprehensive radon survey has been carried out in Baita radon-prone area, Transylvania, Romania, in 4 localities (Baita, Nucet, Finate, and Cimpani) situated in the vicinity of former Romanian uranium mines. Indoor radon concentrations have been measured in 1128 ground floor rooms and cellars of 303 family houses by using CR-39 diffusion type radon detectors. The annual average of indoor radon concentration for Baita area was found to be 241 {+-} 178 Bq m{sup -3}, which is about two times higher than the average value of 126 Bq m{sup -3}, computed for Romania. About 28% of investigated houses exceed the reference level of radon gas in dwellings of 300 Bq m{sup -3}. The indoor radon measurements on each house have been carried out in several rooms simultaneously with the aim of obtaining a more detailed picture on the exposure to radon in the studied area. An analysis on the variability of radon levels among floors (floor-to-floor variation) and rooms (room-to-room variation) and also the influence of factors like the presence of cellar or the age of the building is presented. The coefficient of variation (CV) within ground floor rooms of the same house (room-to-room variation) ranged between 0.9 and 120.8%, with an arithmetic mean of 46.2%, a large variability among rooms within surveyed dwellings being clearly identified. The mean radon concentration in bedrooms without cellar was higher than in bedrooms above the cellar, the difference being statistically significant (t test, one tail, p < 0.001, n = 82). For houses built during 1960-1970 an increasing trend for radon levels was observed, but overall there was no significant difference in indoor radon concentrations by age of dwelling (one-way ANOVA test, p > 0.05). - Highlights: Black-Right-Pointing-Pointer The annual average of indoor radon concentration for Baita area was 241 {+-} 178 Bq m{sup -3}. Black-Right-Pointing-Pointer A large variability among rooms within surveyed dwellings was clearly evidenced

  12. Thorough investigations on indoor radon in Băiţa radon-prone area (Romania).

    Science.gov (United States)

    Cucoş Dinu, Alexandra; Cosma, Constantin; Dicu, Tiberius; Begy, Robert; Moldovan, Mircea; Papp, Botond; Niţă, Dan; Burghele, Bety; Sainz, Carlos

    2012-08-01

    A comprehensive radon survey has been carried out in Băiţa radon-prone area, Transylvania, Romania, in 4 localities (Băiţa, Nucet, Fînaţe, and Cîmpani) situated in the vicinity of former Romanian uranium mines. Indoor radon concentrations have been measured in 1128 ground floor rooms and cellars of 303 family houses by using CR-39 diffusion type radon detectors. The annual average of indoor radon concentration for Băiţa area was found to be 241±178 Bq m(-3), which is about two times higher than the average value of 126 Bq m(-3), computed for Romania. About 28% of investigated houses exceed the reference level of radon gas in dwellings of 300 Bq m(-3). The indoor radon measurements on each house have been carried out in several rooms simultaneously with the aim of obtaining a more detailed picture on the exposure to radon in the studied area. An analysis on the variability of radon levels among floors (floor-to-floor variation) and rooms (room-to-room variation) and also the influence of factors like the presence of cellar or the age of the building is presented. The coefficient of variation (CV) within ground floor rooms of the same house (room-to-room variation) ranged between 0.9 and 120.8%, with an arithmetic mean of 46.2%, a large variability among rooms within surveyed dwellings being clearly identified. The mean radon concentration in bedrooms without cellar was higher than in bedrooms above the cellar, the difference being statistically significant (t test, one tail, pradon levels was observed, but overall there was no significant difference in indoor radon concentrations by age of dwelling (one-way ANOVA test, p>0.05).

  13. Radon measurements in some areas in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Hamid Khan, M.A. [Physics Division, Atomic Energy Centre, Bangladesh Atomic Energy Commission, P.O. Box 164, Dhaka-1000 (Bangladesh)], E-mail: hamidkhan1950@yahoo.com; Chowdhury, M.S. [Physics Department, Dhaka University, Dhaka-1000 (Bangladesh)

    2008-08-15

    A survey of radon level measurements using CR-39 has been carried out in some of urban and rural residential areas and one gas explosion area in Bangladesh. The lowest level of radon concentration was found to be 49Bqm{sup -3} inside a hospital in Cox's Bazar district and the highest level was found to be 835Bqm{sup -3} inside a mud-made old residential house in Sylhet city. It was observed that old residential houses were found to have higher levels of radon concentrations compared to newly built houses. The radon level at the gas explosion area at Magurchara in Moulvibazar district was found to be 408{+-}98Bqm{sup -3}.

  14. GEOMETRICALLY INVARIANT WATERMARKING BASED ON RADON TRANSFORMATION

    Institute of Scientific and Technical Information of China (English)

    Cai Lian; Du Sidan; Gao Duntang

    2005-01-01

    The weakness of classical watermarking methods is the vulnerability to geometrical distortions that widely occur during normal use of the media. In this letter, a new imagewatermarking method is presented to resist Rotation, Scale and Translation (RST) attacks. The watermark is embedded into a domain obtained by taking Radon transform of a circular area selected from the original image, and then extracting Two-Dimensional (2-D) Fourier magnitude of the Radon transformed image. Furthermore, to prevent the watermarked image from degrading due to inverse Radon transform, watermark signal is inversely Radon transformed individually.Experimental results demonstrate that the proposed scheme is able to withstand a variety of attacks including common geometric attacks.

  15. Dependency of radon entry on pressure difference

    Science.gov (United States)

    Kokotti, H.; Kalliokoski, P.; Jantunen, M.

    Radon levels, ventilation rate and pressure differences were monitored continuously in four apartment houses with different ventilation systems. Two of them were ventilated by mechanical exhaust, one by mechanical supply and exhaust, and one by natural ventilation. The two-storey houses were constructed from concrete elements on a slab and located on a gravel esker. It was surprising to find that increasing the ventilation rate increased levels of radon in the apartments. Increased ventilation caused increased outdoor-indoor pressure difference, which in turn increased the entry rate of radon and counteracted the diluting effect of ventilation. The increase was significant when the outdoor-indoor pressure difference exceeded 5 Pa. Especially in the houses with mechanical exhaust ventilation the pressure difference was the most important factor of radon entry rate, and contributed up to several hundred Bq m -3 h -1.

  16. Radon measurement using a liquid scintillation spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Taeko; Morishima, Hiroshige; Kawai, Hiroshi; Kondo, Sohei (Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst.); Mifune, Masaki; Konishi, Masanobu; Shirai, Chiaki

    1992-12-01

    A convenient radon detecting device for the purpose of estimating natural radiation exposure is described. The [alpha] radioactivity of radon gas absorbed in fine active carbon particles exposed to air is measured with a liquid scintillation spectrometer (Packard-PICO-RAD system). Its detection limits are 2mBq/l in air and 0.5 Bq/l in water with an accuracy of about 10 %. Radon concentrations at Misasa hot springs in Tottori prefecture were measured using this method. They were 0.16 [approx] 7.7 Bq/l in a bath room and 0.057 [approx] 0.36 Bq/l outdoors. Radon concentrations of the hot springs were 82 [approx] 1,700 Bq/l. (author).

  17. Radon Transform and Light-Cone Distributions

    Science.gov (United States)

    Teryaev, O. V.

    2016-08-01

    The relevance of Radon transform for generalized and transverse momentum dependent parton distributions is discussed. The new application for conditional (fracture) parton distributions and dihadron fragmentation functions is suggested.

  18. Radon in private drinking water wells.

    Science.gov (United States)

    Otahal, P; Merta, J; Burian, I

    2014-07-01

    At least 10% of inhabitants in the Czech Republic are supplied with water from private sources (private wells, boreholes). With the increasing cost of water, the number of people using their own sources of drinking water will be likely to increase. According to the Decree of the State Office for Nuclear Safety about the Radiation Protection 307/2002 as amended by Decree 499/2005, the guideline limit for the supplied drinking water ('drinking water for public supply') for radon concentration is 50 Bq·l(-1). This guideline does not apply to private sources of drinking water. Radon in water influences human health by ingestion and also by inhalation when radon is released from water during showering and cooking. This paper presents results of measurements of radon concentrations in water from private wells in more than 300 cases. The gross concentration of alpha-emitting radionuclides and the concentrations of radium and uranium were also determined.

  19. El gas radon y la hormesis

    National Research Council Canada - National Science Library

    Garzon Valencia, Gustavo

    2006-01-01

    ..., el cual sale desde el interior de la Tierra. Una construccion con poca ventilacion puede servir de lugar de acumulacion del gas radon y por lo tanto puede aumentar las dosis efectivas de radiactividad sobre el organismo de sus residentes...

  20. Radon Exhalation Considered in Building Material Standard

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>In order to investigate the relationship between radon exhalation and specific activity of natural nuclides in building material, here different kinds of samples of building materials were measured by the

  1. Attenuated radon transform: theory and application in medicine and biology

    Energy Technology Data Exchange (ETDEWEB)

    Gullberg, G.T.

    1979-06-01

    A detailed analysis is given of the properties of the attenuated Radon transform and of how increases in photon attenuation influence the numerical accuracy and computation efficiency of iterative and convolution algorithms used to determine its inversion. The practical applications for this work involve quantitative assessment of the distribution of injected radiopharmaceuticals and radionuclides in man and animals for basic physiological and biochemical studies as well as clinical studies in nuclear medicine. A mathematical structure is developed using function theory and the theory of linear operators on Hilbert spaces which lends itself to better understanding the spectral properties of the attenuated Radon transform. The continuous attenuated Radon transform reduces to a matrix operator for discrete angular and lateral sampling, and the reconstruction problem reduces to a system of linear equations. For the situation of variable attenuation coefficient frequently found in nuclear medicine applications of imaging the heart and chest, the procedure developed in this thesis involves iterative techniques of performing the generalized inverse. For constant attenuation coefficient less than 0.15 cm/sup -1/, convolution methods can reliably reconstruct a 30 cm object with 0.5 cm resolution. However, for high attenuation coefficients or for the situation where there is variable attenuation such as reconstruction of distribution of isotopes in the heart, iterative techniques developed in this thesis give the best results. (ERB)

  2. Radon gamma-ray spectrometry with YAP:Ce scintillator

    CERN Document Server

    Plastino, W; De Notaristefani, F

    2002-01-01

    The detection properties of a YAP:Ce scintillator (YAlO sub 3 :Ce crystal) optically coupled to a Hamamatsu H5784 photomultiplier with standard bialkali photocathode have been analyzed. In particular, the application to radon and radon-daughters gamma-ray spectrometry was investigated. The crystal response has been studied under severe extreme conditions to simulate environments of geophysical interest, particularly those found in geothermal and volcanic areas. Tests in water up to a temperature of 100 deg.C and in acids solutions such as HCl (37%), H sub 2 SO sub 4 (48%) and HNO sub 3 (65%) have been performed. The measurements with standard radon sources provided by the National Institute for Metrology of Ionizing Radiations (ENEA) have emphasized the non-hygroscopic properties of the scintillator and a small dependence of the light yield on temperature and HNO sub 3. The data collected in this first step of our research have pointed out that the YAP:Ce scintillator can allow high response stability for rad...

  3. Effects of residential mobility on individual versus population risk of radon-related lung cancer.

    Science.gov (United States)

    Warner, K E; Courant, P N; Mendez, D

    1995-12-01

    The U.S. Environment Protection Agency (EPA) does not consider the effects of normal patterns of residential mobility in estimating individual radon-related lung cancer risks. As a consequence, the EPA's population risk estimates may have little bearing on individual risks, and remediation of high-radon homes may have only small health benefits for the individual who remediate their homes. Through a stimulation analysis, we examine the effects of residential mobility on random exposure and lung cancer risk. Given normal mobility, only 7% of eventual radon-related mortality among current 30 year old will occur in the 5% currently living in homes above pCi/l (the EPA's action level for remediation) in contrast with you estimate of 31% of deaths when mobility's ignored. About 10 pCi/l the no-mobility assumption implies 10.3% of deaths, compared to only 0.4% when mobility taken into account. We conclude that knowledge of one's current random exposure not necessarily a useful guide to one's risk, especially for residents of the high-radon homes targeted for remediation by the EPA. The risk of such individuals is like to be substantially lower than that implied in the EPA's risk charts. If people currently living in high radon homes remediate their houses, the majority of the resulting health benefits will accrue to future occupants of their homes.

  4. Radon risk mapping in southern Belgium: an application of geostatistical and GIS techniques.

    Science.gov (United States)

    Zh, H C; Charlet, J M; Poffijn, A

    2001-05-14

    A data set of long-term radon measurements in approximately 2200 houses in southern Belgium has been collected in an on-going national radon survey. The spatial variation of indoor Rn concentrations is modelled by variograms. A radon distribution map is produced using the log-normal kriging technique. A GIS is used to digitise, process and integrate a variety of data, including geological maps, Rn concentrations associated with house locations and an administrative map, etc. It also allows evaluation of the relationships between various spatial data sets with the goal of producing radon risk maps. Based on geostatistical mapping and spatial analysis, we define three categories of risk areas: high risk, medium risk and low risk area. The correlation between radon concentrations and geological features is proved in this study. High and medium Rn risk zones are dominantly situated in bedrock from the Cambrian to Lower Devonian, although a few medium risk zones are within the Jurassic. It is evident that high-risk zones are related to a strongly folded and fractured context.

  5. RADON AND CARCINOGENIC RISK IN MOSCOW

    Directory of Open Access Journals (Sweden)

    S. M. Golovanev

    2015-01-01

    Full Text Available Objective: comparative evaluation of carcinogenic risk inMoscowfrom radon in indoor and atmospheric pollutants.Materials and methods: the lung cancer incidence in Moscow; radiation-hygienic passport of the territory; .U.S. EPA estimated average age at all and radon induced deaths, years of life lost; Report of UNSCEAR 2006 and WHO handbook on indoor radon, 2009. Trend analysis of incidence; evaluation of the excess relative risk; assessment of ratio radon-induced population risk and published values оf total population carcinogenic risk from chemical carcinogens.Results: it is shown that the 304 cases of lung cancer per year (1. 85 10-3 on average from 2006 to 2011 (21280diseases for 70 years in addition to background level induced by radon; the differences in average trends of all lungcancer incidence in the districts can exceed 25%.Conclusion. The potential of risk reduction by measures of mitigation radon concentration exceeds 5 times the cost efficiency to reduce emissions from vehicles and can reduce cancer incidence, on average 236 cases per year; population risk 16520 cases over 70 years or save not less than 2832 person-years of life per year. The annual effect of reducing losses from not-survival of 12 years as a result of radon-induced lung cancer deaths exceeds 14160000 dollars. The evaluating of the carcinogenic risk from radon in accordance with the definition of population risk increases the predictive evaluation of the effectiveness of preventive measures more than twice.

  6. Neutron activation analysis of ceramic tiles and its component and radon exhalation rate.

    Science.gov (United States)

    El-Shershaby, A; Sroor, A; Ahmed, F; Abdel-Haleem, A S; Abdel, Z

    2004-01-01

    The concentrations of 20 trace elements in several ceramics tiles and ceramic composites used in Egypt were elementally analyzed by neutron activation analysis(NAA) technique. The samples and standard were irradiated with reactor for 4 h (in the Second Research Egyptian Reactor(Et-RR-2)) with thermal neutron flux 5.9 x 10(13) n/(cm2 x s). The gamma-ray spectra obtained were measured for several times by means of the hyper pure germanium detection system(HPGe). Also a solid state nuclear track detector(SSNTD) CR-39, was used to measure the emanation rate of radon for these samples. The radium concentrations were found to vary from 0.39-3.59 ppm and the emanation rates were found to vary from (0.728-5.688) x 10(-4) kg/(m2 x s). The elemental analysis of the ceramic tiles and ceramic composites have a great importance in assigning the physical properties and in turn the quality of the material.

  7. Evaluation of the atmospheric transport in a GCM using radon measurements: sensitivity to cumulus convection parameterization

    Directory of Open Access Journals (Sweden)

    K. Zhang

    2008-05-01

    Full Text Available The radioactive species radon (222Rn has long been used as a test tracer for the numerical simulation of large scale transport processes. In this study, radon transport experiments are carried out using an atmospheric GCM with a finite-difference dynamical core, the van Leer type FFSL advection algorithm, and two state-of-the-art cumulus convection parameterization schemes. Measurements of surface concentration and vertical distribution of radon collected from the literature are used as references in model evaluation.

    The simulated radon concentrations using both convection schemes turn out to be consistent with earlier studies with many other models. Comparison with measurements indicates that at the locations where significant seasonal variations are observed in reality, the model can reproduce both the monthly mean surface radon concentration and the annual cycle quite well. At those sites where the seasonal variation is not large, the model is able to give a correct magnitude of the annual mean. In East Asia, where radon simulations are rarely reported in the literature, detailed analysis shows that our results compare reasonably well with the observations.

    The most evident changes caused by the use of a different convection scheme are found in the vertical distribution of the tracer. The scheme associated with weaker upward transport gives higher radon concentration up to about 6 km above the surface, and lower values in higher altitudes. In the lower part of the atmosphere results from this scheme does not agree as well with the measurements as the other scheme. Differences from 6 km to the model top are even larger, although we are not yet able to tell which simulation is better due to the lack of observations at such high altitudes.

  8. Evaluation of the atmospheric transport in a GCM using radon measurements: sensitivity to cumulus convection parameterization

    Directory of Open Access Journals (Sweden)

    K. Zhang

    2008-02-01

    Full Text Available The radioactive species radon (222Rn has long been used as a test tracer for the numerical simulation of large scale transport processes. In this study, radon transport experiments are carried out using an atmospheric GCM with a finite-difference dynamical core, the van Leer type FFSL advection algorithm and two state-of-the-art cumulus convection parameterization schemes. Measurements of surface concentration and vertical distribution of radon collected from literature are used as references in model evaluation.

    The simulated radon concentrations using both convection schemes turn out to be consistent with earlier studies with many other models. Comparison with measurements indicates that at the locations where significant seasonal variations are observed in reality, the model can reproduce both the monthly mean surface radon concentration and the annual cycle quite well. At those sites where the seasonal variation is not large, the model is able to give a correct magnitude of the annual mean. In East Asia, where radon simulations are rarely reported in literature, detailed analysis shows that our results compare reasonably well with the observations.

    The most evident changes caused by the use of a different convection scheme are found in the vertical distribution of the tracer. The scheme associated with a weaker upward transport gives higher radon concentration up to about 6 km above the surface, and lower values in higher altitudes. In the lower part of the atmosphere results from this scheme does not agree as well with the measurements as the other scheme. Differences from 6 km to the model top are even larger, although we are not yet able to tell which simulation is better due to the lack of observations at such high altitudes.

  9. Filtering of the Radon transform to enhance linear signal features via wavelet pyramid decomposition

    Science.gov (United States)

    Meckley, John R.

    1995-09-01

    wavelet coefficient energy. The detection algorithm provides an estimate of the line offset, orientation, and length that is then used to index the appropriate filter shape. Additional wavelet pyramid decomposition is performed in areas of high energy to refine the line position estimate. After filtering, the new Radon transform is generated by inverting the wavelet pyramid. The Radon transform is then inverted by filtered backprojection to produce the final 2D signal estimate with the enhanced linear features. The wavelet-based method is compared to both the Fourier and the nonlinear filtering with examples of sparse and dense shapes in imaging, acoustics and medical tomography with test images of noisy concentric lines, a real spectrogram of a blow fish (a very nonstationary spectrum), and the Shepp Logan Computer Tomography phantom image. Both qualitative and derived quantitative measures demonstrate the improvement of wavelet-based filtering. Additional research is suggested based on these results. Open questions include what level(s) to use for detection and filtering because multiple-level representations exist. The lower levels are smoother at reduced spatial resolution, while the higher levels provide better response to edges. Several examples are discussed based on analytical and phenomenological arguments.

  10. Personal radon dosimetry from eyeglass lenses.

    Science.gov (United States)

    Fleischer, R L; Meyer, N R; Hadley, S A; MacDonald, J; Cavallo, A

    2001-01-01

    Eyeglass lenses are commonly composed of allyl-diglycol carbonate (CR-39), an alpha-particle detecting plastic, thus making such lenses personal radon dosemeters. Samples of such lenses have been obtained, etched to reveal that radon and radon progeny alpha tracks can be seen in abundance, and sensitivities have been calibrated in radon chambers as a primary calibration, and with a uranium-based source of alpha particles as a convenient secondary standard. With one exception natural, environmental (fossil) track densities ranged from less than 3,000 to nearly 70,000 per cm2 for eyeglasses that had been worn for various times from one to nearly five years. Average radon concentrations to which those wearers were exposed are inferred to be in the range 14 to 130 Bq x m(-3) (0.4 to 3.5 pCi x l(-1)). A protocol for consistent, meaningful readout is derived and used. In the exceptional case the fossil track density was 1,780,000 cm(-2) and the inferred (24 h) average radon concentration was 6500 Bq x m(-3) (175 pCi x l(-1)) for a worker at an inactive uranium mine that is used for therapy.

  11. The influence of chemical etching time on efficiency of radon detection using CR-39

    Energy Technology Data Exchange (ETDEWEB)

    Reway, Adriana P.; Kappke, Jaqueline; Narloch, Danielle C., E-mail: adrireway@hotmail.com, E-mail: jaquelinekappke@gmail.com, E-mail: daninarloch@hotmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Departamento Academico de Fisica; Del Claro, Flavia; Paschuk, Sergei A., E-mail: flaviadelclaro@gmail.com, E-mail: spaschuk@gmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Programa de Pos-Graduaca em Engenharia Eletrica e Informatica Industrial; Correa, Janine N., E-mail: janine_nicolosi@hotmail.com [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Departamento Academico de Construcao Civil

    2015-07-01

    Natural radiation is the principal source of human exposure to ionizing radiation. Radon is noble radioactive gas that emanates from the soil and rocks entering the atmosphere of dwellings where it could be accumulated. The inhalation of {sup 222}Rn represents a significant health risk. Solid-State Nuclear Track Detectors (SSNTD) represents an efficient method for alpha particle detection and measurements of the activity concentration of {sup 222}Rn. The aim of present work was to study the etching time impact on CR-39 efficiency in radon activity measurements. The investigation was performed using 80 CR-39 detectors, which were exposed to a source of radon. After the exposition, alpha particle tracks development was achieved by chemical etching using 6.25M NaOH solution and ethanol (2%) at 70°C. Etching alpha particle tracks were identified and counted manually using the optical microscope with magnification of 100x and glass overlay mask. The etching time ranged from 7 to 14 hours. The results show that there is an increase in the number of visible tracks with increased etching time. The number of traces obtained for 7 hours and 8 hours of revelation was 1430 +/- 90 and 2090 +/- 160, respectively. However, for etching time of 13 and 14 hours was not observed statistical increase in the number of visible tracks. The number of tracks in this situation was 3630 +/- 180 and 3870 +/- 160 to 13 and 14 hours etching. Thus, for assumed etching parameters, the etching optimal time was observed 14 hours. (author)

  12. RADON REDUCTION AND RADON-RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK - VOLUME 2: APPENDICES

    Science.gov (United States)

    Growing concern about health risks associated with exposure to indoor radon, a radioactive gas found in varying amounts in nearly all houses, has underscored the need for dependable radon reduction methods in existing and newly constructed houses. Responding to this need, the U....

  13. Radon and radon-daughter concentrations in air in the vicinity of the Anaconda Uranium Mill

    Energy Technology Data Exchange (ETDEWEB)

    Momeni, M H; Lindstrom, J B; Dungey, C E; Kisieleski, W E

    1979-11-01

    Radon concentration, working level, and meteorological variables were measured continuously from June 1977 through June 1978 at three stations in the vicinity of the Anaconda Uranium Mill with measurements integrated to hourly intervals. Both radon and daughters show strong variations associated with low wind velocities and stable atmospheric conditions, and diurnal variations associated with thermal inversions. Average radon concentration shows seasonal dependence with highest concentrations observed during fall and winter. Comparison of radon concentrations and working levels between three stations shows strong dependence on wind direction and velocity. Radon concentrations and working-level distributions for each month and each station were analyzed. The average maximum, minimum, and modal concentration and working levels were estimated with observed frequencies. The highest concentration is 11,000 pCi/m/sup 3/ on the tailings. Working-level variations parallel radon variations but lag by less than one hour. The highest working levels were observed at night when conditions of higher secular radioactive equilibrium for radon daughters exist. Background radon concentration was measured at two stations, each located about 25 km from the mill, and the average is 408 pCi/m/sup 3/. Average working-level background is 3.6 x 10/sup -3/.

  14. Determination of air-loop volume and radon partition coefficient for measuring radon in water sample.

    Science.gov (United States)

    Lee, Kil Yong; Burnett, William C

    A simple method for the direct determination of the air-loop volume in a RAD7 system as well as the radon partition coefficient was developed allowing for an accurate measurement of the radon activity in any type of water. The air-loop volume may be measured directly using an external radon source and an empty bottle with a precisely measured volume. The partition coefficient and activity of radon in the water sample may then be determined via the RAD7 using the determined air-loop volume. Activity ratios instead of absolute activities were used to measure the air-loop volume and the radon partition coefficient. In order to verify this approach, we measured the radon partition coefficient in deionized water in the temperature range of 10-30 °C and compared the values to those calculated from the well-known Weigel equation. The results were within 5 % variance throughout the temperature range. We also applied the approach for measurement of the radon partition coefficient in synthetic saline water (0-75 ppt salinity) as well as tap water. The radon activity of the tap water sample was determined by this method as well as the standard RAD-H2O and BigBottle RAD-H2O. The results have shown good agreement between this method and the standard methods.

  15. Application of a radon model to explain indoor radon levels in a Swedish house

    CERN Document Server

    Font, L; Jönsson, G; Enge, W; Ghose, R

    1999-01-01

    Radon entry from soil into indoor air and its accumulation indoors depends on several parameters, the values of which normally depend on the specific characteristics of the site. The effect of a specific parameter is often difficult to explain from the result of indoor radon measurements only. The adaptation of the RAGENA (RAdon Generation, ENtry and Accumulation indoors) model to a Swedish house to characterise indoor radon levels and the relative importance of the different radon sources and entry mechanisms is presented. The building is a single-zone house with a naturally-ventilated crawl space in one part and a concrete floor in another part, leading to different radon levels in the two parts of the building. The soil under the house is moraine, which is relatively permeable to radon gas. The house is naturally-ventilated. The mean indoor radon concentration values measured with nuclear track detectors in the crawl-space and concrete parts of the house are respectively 75+-30 and 200+-80 Bq m sup - sup 3...

  16. RADON REDUCTION AND RADON-RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK - VOLUME 2: APPENDICES

    Science.gov (United States)

    Growing concern about health risks associated with exposure to indoor radon, a radioactive gas found in varying amounts in nearly all houses, has underscored the need for dependable radon reduction methods in existing and newly constructed houses. Responding to this need, the U....

  17. A campaign of discrete radon concentration measurements in soil of Niska Banja town, Serbia

    Energy Technology Data Exchange (ETDEWEB)

    Zunic, Z.S. [Institute of Nuclear Sciences ' Vinca' , ECE LAB, P.O. Box 522, 11001 Belgrade, Serbia (Serbia); Kozak, K. [Henryk Niewodniczanski Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland)], E-mail: Krzysztof.Kozak@ifj.edu.pl; Ciotoli, G. [Department of Earth Sciences, University of Rome ' La Sapienza' , Piazzale A. Moro, 5-00185 Rome (Italy); Ramola, R.C. [Department of Physics, H.N.B. Garhwal University, Badshahi Thaul Campus, Tehri Garhwal 249 199 (India); Kochowska, E. [Henryk Niewodniczanski Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland); Ujic, P.; Celikovic, I. [Institute of Nuclear Sciences ' Vinca' , ECE LAB, P.O. Box 522, 11001 Belgrade (Serbia); Mazur, J.; Janik, M. [Henryk Niewodniczanski Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland); Demajo, A. [Institute of Nuclear Sciences ' Vinca' , ECE LAB, P.O. Box 522, 11001 Belgrade (Serbia); Birovljev, A. [RADONLAB, Forskningsveien 3 B, 0373 Oslo (Norway); Bochicchio, F. [Italian National Institute of Health, Department of Technology and Health, Unit of Radioactivity and Related Health Effects, Viale Regina Elena 299, 00161 Rome (Italy); Yarmoshenko, I.V. [Radiation Laboratory Institute of Industrial Ecology, Ural Branch of Russian Academy of Sciences, 20A S. Kovalevskoy Street, Ekaterinburg 620219 (Russian Federation); Kryeziu, D. [Low-level Counting Laboratory, Faradaygasse 3, Arsenal Objekt 214, A-1030 Vienna (Austria); Olko, P. [Henryk Niewodniczanski Institute of Nuclear Physics PAN, ul. Radzikowskiego 152, PL-31-342 Cracow (Poland)

    2007-11-15

    The first radon soil gas survey in Serbia, using passive detectors (SSNTD, CR-39), was carried out in June 2005 at field sites in Niska Banja town. The aim of the survey was to identify risk zones characterised by high levels of this radioactive gas. Radon measurements were made at the depth of 50 cm, in the ground according to a systematic grid pattern. Furthermore, at all 48 measurement points, the surface gamma dose rates in the air was also measured at the same locations and soil samples were collected for gamma spectrometric analysis for the radionuclides {sup 226}Ra, {sup 228}Th and {sup 40}K. Radon concentrations were found to range from 1270 to 155000Bqm{sup -3} with an average of 33765Bqm{sup -3} and a median value of 12626Bqm{sup -3}. The geometrical mean value and geometrical standard deviation were calculated as 16160Bqm{sup -3} and 3.5Bqm{sup -3}, respectively. Gamma dose rate varies from 92 to 316nGyh{sup -1}, with an average of 132nGyh{sup -1}. The radium content in collected soil samples ranges from 24 to 1810Bqkg{sup -1} with an average of 187Bqkg{sup -1}. High correlations (r{sup 2}>0.8) between soil gas radon concentration, gamma dose rate and {sup 226}Ra content in soil were found for each pair. The distribution of radon concentrations in soil gas shows bimodal shape.

  18. How to Ensure Low Radon Concentrations in Indoor Environments

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn; Wraber, Ida Kristina

    2011-01-01

    This paper focuses on methods for measuring radon levels in the indoor air in buildings as well as on concrete solutions that can be carried out in the building to prevent radon leakage and to lower the radon concentration in the indoor air of new buildings. The radon provision in the new Danish...... Building Regulations from 2010 has been tightened as a result of new recommendations from the World Health Organization. Radon can cause lung cancer and it is not known whether there is a lower limit for its harmfulness. It is therefore important to reduce the radon concentration as much as possible in new...... buildings. The airtightness is a major factor when dealing with radon in buildings. Above the ground it is important to build airtight in compliance with energy requirements and against the ground it is important to prevent radon from seeping into the building. There is a direct connection between...

  19. 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.

  20. Radon removal from gaseous xenon with activated charcoal

    Science.gov (United States)

    Abe, K.; Hieda, K.; Hiraide, K.; Hirano, S.; Kishimoto, Y.; Kobayashi, K.; Koshio, Y.; Liu, J.; Martens, K.; Moriyama, S.; Nakahata, M.; Nishiie, H.; Ogawa, H.; Sekiya, H.; Shinozaki, A.; Suzuki, Y.; Takachio, O.; Takeda, A.; Ueshima, K.; Umemoto, D.; Yamashita, M.; Hosokawa, K.; Murata, A.; Otsuka, K.; Takeuchi, Y.; Kusaba, F.; Motoki, D.; Nishijima, K.; Tasaka, S.; Fujii, K.; Murayama, I.; Nakamura, S.; Fukuda, Y.; Itow, Y.; Masuda, K.; Nishitani, Y.; Takiya, H.; Uchida, H.; Kim, Y. D.; Kim, Y. H.; Lee, K. B.; Lee, M. K.; Lee, J. S.; Xmass Collaboration

    2012-01-01

    Many low background experiments using xenon need to remove radioactive radon to improve their sensitivities. However, no method of continually removing radon from xenon has been described in the literature. We studied a method to remove radon from xenon gas through an activated charcoal trap. From our measurements we infer a linear relationship between the mean propagation velocity vRn of radon and vXe of xenon in the trap with vRn/vXe=(0.96±0.10)×10-3 at -85 °C. As the mechanism for radon removal in this charcoal trap is its decay, knowledge of this parameter allows us to design an efficient radon removal system for the XMASS experiment. The verification of this system found that it reduces radon by a factor of 0.07, which is in line with its expected average retention time of 14.8 days for radon.

  1. Radon-safe new buildings, documentation and technology development. Main report; Radonsikring i nybyggeri, dokumentation og teknologiudvikling. Hovedrapport

    Energy Technology Data Exchange (ETDEWEB)

    Breddam Overgaard, L.; Bruun Petersen, J.; Neerup Jeppesen, M.

    2011-07-01

    The project is carried out as three separate subprojects, with subproject 1 as the principal project. Subproject 1A (field tests of radon penetration). In subproject 1, the resilience to radon of six different house designs has been investigated (totalling 23 houses). The study includes both practical experiences (what happens on site) and radon measurements in the completed houses. The practical study of the subproject points out, a high risk of errors in implementing radon mitigation actions in the construction phase, and of subsequent disregard by various contractors. For instance the documentary radon measurements surprisingly show the greatest radon infiltration in the full floor membrane house design. Furthermore the investigations indicate that a radon cavity barrier placed above the concrete slab (house design 3 and 5) does not provide the same impermeability as a barrier placed below the slab. Moreover, it appears that leakages at service installations are of critical importance. In 8 of all 16 dwellings the annual average radon concentration was found above 100 Bq/m3 which represents the recommended maximum concentration for new constructions in the Danish Building Code 2010. Subproject 1B (sub slab ventilation). The effect of passive ventilation in the sub slab capillary break layer has been studied in three houses. The investigations demonstrate an indoor radon concentration reduction of 20-42 %. Furthermore a sub slab radon concentration reduction of 40-99.6 % is demonstrated. Overall it is assessed that considerable radon exposure reductions can be achieved by establishing passive ventilation of the sub slab capillary break layer. Subproject 2 (laboratory tests of material and design permeability). An experimental setup has been developed to measure the amount of gas penetrating a given structural detail, at a known differential pressure and gas concentration. In the study it is concluded that the relatively inexpensive method of sealing service

  2. Radon potential mapping of the Tralee-Castleisland and Cavan areas (Ireland) based on airborne gamma-ray spectrometry and geology.

    Science.gov (United States)

    Appleton, J D; Doyle, E; Fenton, D; Organo, C

    2011-06-01

    The probability of homes in Ireland having high indoor radon concentrations is estimated on the basis of known in-house radon measurements averaged over 10 km × 10 km grid squares. The scope for using airborne gamma-ray spectrometer data for the Tralee-Castleisland area of county Kerry and county Cavan to predict the radon potential (RP) in two distinct areas of Ireland is evaluated in this study. Airborne data are compared statistically with in-house radon measurements in conjunction with geological and ground permeability data to establish linear regression models and produce radon potential maps. The best agreement between the percentage of dwellings exceeding the reference level (RL) for radon concentrations in Ireland (% > RL), estimated from indoor radon data, and modelled RP in the Tralee-Castleisland area is produced using models based on airborne gamma-ray spectrometry equivalent uranium (eU) and ground permeability data. Good agreement was obtained between the % > RL from indoor radon data and RP estimated from eU data in the Cavan area using terrain specific models. In both areas, RP maps derived from eU data are spatially more detailed than the published 10 km grid map. The results show the potential for using airborne radiometric data for producing RP maps.

  3. The Influence of Internal Wall and Floor Covering Materials and Ventilation Type on Indoor Radon and Thoron Levels in Hospitals of Kermanshah, Iran

    Science.gov (United States)

    Pirsaheb, Meghdad; Najafi, Farid; Haghparast, Abbas; Hemati, Lida; Sharafi, Kiomars; Kurd, Nematullah

    2016-01-01

    Background Building materials and the ventilation rate of a building are two main factors influencing indoor radon and thoron levels (two radioactive gases which have the most important role in human natural radiation exposure within dwellings). Objectives This analytical descriptive study was intended to determine the relationship between indoor radon and thoron concentrations and the building materials used in interior surfaces, as well as between those concentrations and the type of ventilation system (natural or artificial). Materials and Methods 102 measurements of radon and thoron levels were taken from different parts of three hospital buildings in the city of Kermanshah in the west of Iran, using an RTM-1688-2 radon meter. Information on the type of building material and ventilation system in the measurement location was collected and then analyzed using Stata 8 software and multivariate linear regression. Results In terms of radon and thoron emissions, travertine and plaster were found to be the most appropriate and inappropriate covering for walls, respectively. Furthermore, granite and travertine were discovered to be inappropriate materials for flooring, while plastic floor covering was found suitable. Natural ventilation performed better for radon, while artificial ventilation worked better for thoron. Conclusions Internal building materials and ventilation type affect indoor radon and thoron concentrations. Therefore, the use of proper materials and adequate ventilation can reduce the potential human exposure to radon and thoron. This is of utmost importance, particularly in buildings with a high density of residents, including hospitals.

  4. Radon

    Science.gov (United States)

    ... face' showdown over Obama-era tailpipe rule Blog: Yoga, Tai Chi and Your Lungs: The Benefits of ... list_name').hide(); } $("#local_list_xml").quickPagination(); }, error: function() { console.log("An error occurred while processing XML ...

  5. Assessment and prevention of radioactive risk due to 222Radon on University Premises in Genoa, Italy.

    Science.gov (United States)

    Panatto, D; Gasparini, R; Benatti, U; Gallelli, G

    2006-12-01

    From October 2004 to September 2005, Radon222 activity in high-risk indoor spaces used by employees and students at the University of Genoa was measured with CR-39 nuclear track detectors. The mean concentration in winter (78.9 Bq/m3 +/- 74.92 S.D.) was low in relation to the microenvironment considered. When data were broken down by type and location of the spaces, no significant differences were found, despite the fact that the Genoa conurbation lies on soil of variable geological composition. The dose absorbed by employees was 0.42 mSv/year, with a relative risk of 4.2/1000 cases of Radon-related lung cancer. The dose absorbed by students was 0.28 mSv/year, with a relative risk of 2.5/1000 cases of Radon-related lung cancer. The level of radon activity detected never exceeded the limit of 500 Bq/m3 established by Italian law. Nevertheless, the value of the compound uncertainty index suggested that the real level of Radon contamination could have exceeded 400 Bq/m3 in selected spaces, a value requiring annual concentration tests.