Science.gov

Sample records for indoor radon concentration

  1. Predicting indoor radon-222 concentration

    SciTech Connect

    Stowe, M.H.

    1994-12-31

    Radon, a cause of lung cancer among miners, is being investigated as a source of lung cancer in the general population due to long-term low-level exposures in residences. Assessment of cumulative residential radon exposure entails measurements in past residences, some of which no longer exist or are not accessible. Estimates of radon concentrations in these missing homes are necessary for analysis of the radon-lung cancer association. Various approaches have been used by researchers attempting to predict the distribution of radon measurements in homes from specified geological and building characteristics. This study has modelled the set of basement radon measurements of 3788 Connecticut homes with several of these approaches, in addition to a descriptive tree method not previously utilized, and compared their validity on a random subset of homes not used in model construction. Each geographical and geological variable was more predictive of radon concentration than any of the housing characteristics. The single variable which explained the largest fraction of the variability in radon readings was the mean radon concentration for the zipcode area in which the house was located (R{sup 2} = .157). Soil characteristics at individual housing sites were not available for these analyses. They would be expected to increase the predictive power of the models. Multiple regression models, both additive and multiplicative, were not able to explain more than 22% of the variation in radon readings. Variables found to be significant in these models were zipcode mean, residential radon mean of bedrock unit, building age, type of foundation walls, type of water supply, aeroradioactivity reading, and lithology of the bedrock. A site potential index, based upon a classification of the bedrock underlying the house, was a better predictor of indoor radon level than other single geological variables, yet only explained 8% of the radon variability.

  2. Unusually high indoor radon concentrations

    NASA Astrophysics Data System (ADS)

    Ennemoser, O.; Ambach, W.; Brunner, P.; Schneider, P.; Oberaigner, W.; Purtscheller, F.; Stingl, V.

    Measurements of indoor radon concentrations in the village Umhausen (2600 inhabitants, Ötztal valley, Tyrol, Austria) revealed unusually high indoor radon concentrations up to 274,000 Bq m -3. The medians measured on the basements were 3750 Bq m -3 in winter and 361 Bq m -3 in summer, those on the ground floors were 1180 Bq m -3 and 210 Bq m -3, respectively. Seventy-one per cent of the houses showed basement radon concentrations above the Austrian action level of 400 Bq m -3 in winter, 33% in summer. There are indications that the high radon concentrations are due to a giant rock slide about 8700 years ago. The unusually high radon concentrations in Umhausen coincide with a statistically significant increase in lung cancer mortality. For the period 1970-1991 the age and sex standardized mortality rate is 3.85 (95% confidence interval: 2.9 to 5.1). The control population is the total population of Tyrol (630,000 inhabitants).

  3. Indoor radon concentration forecasting in South Tyrol.

    PubMed

    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.

  4. Indoor radon concentrations in Adana, Turkey.

    PubMed

    Degerlier, M; Celebi, N

    2008-01-01

    The indoor radon concentration in Adana, Turkey was measured in living rooms of 52 houses during winter 2005 and 57 houses during summer 2005. Forty-four houses were selected for both winter and summer researches for estimating seasonal variations. Indoor radon concentrations were measured seasonally over hotter and colder 2 months over the whole year, using CR-39 passive nuclear track radon detectors. The radon concentrations were ranged from 15 to 97 Bq m(-3) on January-February 2005 for 60 d and from 5 to 70 Bq m(-3) on June-July 2005 for 60 d. The average summer concentration measured was 25.8 Bq m(-3) and the average winter concentration was 48.9 Bq m(-3) in 44 houses that observed seasonal variations. The differences between winter and summer periods were ranged from 1 to 77 Bq m(-3). The average value in both winter and summer periods is 37 Bq m(-3) in 44 houses that observed seasonal variations. This value is below the worldwide indoor radon concentration distribution of 46 Bq m(-3). The annual effective dose equivalent from (222)Rn was 0.9 mSv y(-1).

  5. A review on mathematical models for estimating indoor radon concentrations.

    PubMed

    Park, Ji Hyun; Kang, Dae Ryong; Kim, Jinheum

    2016-01-01

    Radiation from natural sources is one of causes of the environmental diseases. Radon is the leading environmental cause of lung cancer next to smoking. To investigate the relationship between indoor radon concentrations and lung cancer, researchers must be able to estimate an individual's cumulative level of indoor radon exposure and to do so, one must first be able to assess indoor radon concentrations. In this article, we outline factors affecting indoor radon concentrations and review related mathematical models based on the mass balance equation and the differential equations. Furthermore, we suggest the necessities of applying time-dependent functions for indoor radon concentrations and developing stochastic models. PMID:26925235

  6. Anti-radon coating for mitigating indoor radon concentration

    NASA Astrophysics Data System (ADS)

    Gao, Grace W. W.; Tang, Y. H.; Tam, C. M.; Gao, X. F.

    Sufficient data has proven that radon and its decay products are the principal noso-genesis to lung and other related cancers. To reduce and control the effects of radon pollution, standards to limit indoor radon concentration have been issued in China and other countries or regions. To echo this, an anti-radon coating has been studied and developed with partial funding support from the Innovation and Technology Fund of the Government of the Hong Kong Special Administrative Region. The coating had been experimented in a newly constructed building where the recorded maximum and average hourly background radon concentrations were recorded at 130,000 Bq m -3 and 100,000 Bq m -3 respectively under a concealed condition. The experimental results from application of the coating have shown an anti-radon efficiency of up to 99.85%, which decreases the indoor radon background concentration down to a safe level in a 72-h measurement. The coating still remains in a good condition currently and effective in anti-radon three years after the application.

  7. Indoor radon and decay products: Concentrations, causes, and control strategies

    SciTech Connect

    Nero, A.V.; Gadgil, A.J.; Nazaroff, W.W.; Revzan, K.L.

    1990-11-01

    This report is another in the on going technical report series that addresses various aspects of the DOE Radon Research Program. It provides an overview of what is known about the behavior of radon and its decay products in the indoor environment and examines the manner in which several important classes of factors -- structural, geological, and meteorological -- affect indoor radon concentrations. Information on US indoor radon concentrations, currently available monitoring methods and novel radon control strategies are also explored. 238 refs., 22 figs., 9 tabs.

  8. Indoor radon

    SciTech Connect

    Rabkin, M.A.; Bodansky, D.

    1988-12-31

    The first awareness of radon as a health hazard came from observations of increased lung cancer incidence among uranium and other miners. During the past decade there has been increasing recognition of the importance of radon in the indoor environment as well. Extrapolations from radon exposures in mines to those in homes indicate that radon will cause a significant number of lung cancer deaths among the general population if its effects are linearly proportional to the magnitude of the exposure. For example, in the United States roughly 5000 to 20,000 lung cancer deaths per year are now attributed to indoor radon. Consistent with this, the effective dose equivalent from indoor radon is larger than the dose from any other radiation source for most people in temperate climates. Radon is a noble gas and can diffuse freely through the air. The most important isotope of radon, Rn-222, is produced in the alpha-particle decay of Ra-226, which is present in all soil and rock as a product of the U-238 decay series. In consequence, radon is present in both the outdoor and indoor environments, primarily due to its escape from the soil into the open air or into houses. The indoor concentrations are usually much higher than the outdoor concentrations, because the radon that enters into houses escapes relatively slowly. 120 refs., 12 tabs.

  9. Distribution of indoor radon concentrations in Pennsylvania, 1990-2007

    USGS Publications Warehouse

    Gross, Eliza L.

    2013-01-01

    Median indoor radon concentrations aggregated according to geologic units and hydrogeologic settings are useful for drawing general conclusions about the occurrence of indoor radon in specific geologic units and hydrogeologic settings, but the associated data and maps have limitations. The aggregated indoor radon data have testing and spatial accuracy limitations due to lack of available information regarding testing conditions and the imprecision of geocoded test locations. In addition, the associated data describing geologic units and hydrogeologic settings have spatial and interpretation accuracy limitations, which are a result of using statewide data to define conditions at test locations and geologic data that represent a broad interpretation of geologic units across the State. As a result, indoor air radon concentration distributions are not proposed for use in predicting individual concentrations at specific sites nor for use as a decision-making tool for property owners to decide whether to test for indoor radon concentrations at specific property locations.

  10. Indoor radon.

    PubMed

    Polpong, P; Bovornkitti, S

    1998-01-01

    The naturally radioactive but chemically inert gas, radon, is formed from the radioactive decay of radium which is part of the uranium series. Radon gas, which has a half life of 3.8 days, must escape from soil particles through air-filled pores in order to enter the atmosphere following the decay of radium. The concentration of radon in the atmosphere varies, depending on the place, time, height above the ground and meteorological conditions. It is thus an inescapable source of radiation exposure, both at home and at work. The potential hazards posed by exposure to radiation from indoor radon gas and its daughter products are of great concern worldwide. Noting of an excessive lung cancer risk among several groups of underground miners exposed to radon and its daughter products, studies on radon concentrations in the workplace and in dwellings have been conducted in many countries. The results have shown that the distribution of radon concentrations are approximately lognormal from which population weighted; the arithmetic mean of radon concentration of 40 Bq.m-3 has been adopted worldwide for dwellings and workplaces. The principal methods for reducing a high indoor radon concentration are: reducing the radon supply by reversing the pressure difference between the building and the soil; raising the resistance of the foundations to soil gas entry; removing the radon sources such as water or underlying soil; diluting the concentration by increasing the ventilation rate; and reducing the concentration of radon progeny by filtering and increasing the circulation of indoor air. Buildings which have a radon concentration higher than 200 Bq.m-3 should be investigated by the national authorities concerned; meanwhile, householders should be advised to take simple temporary precautions, such as increasing ventilation, until a permanent remedy can be effected. PMID:9470322

  11. Indoor radon.

    PubMed

    Polpong, P; Bovornkitti, S

    1998-01-01

    The naturally radioactive but chemically inert gas, radon, is formed from the radioactive decay of radium which is part of the uranium series. Radon gas, which has a half life of 3.8 days, must escape from soil particles through air-filled pores in order to enter the atmosphere following the decay of radium. The concentration of radon in the atmosphere varies, depending on the place, time, height above the ground and meteorological conditions. It is thus an inescapable source of radiation exposure, both at home and at work. The potential hazards posed by exposure to radiation from indoor radon gas and its daughter products are of great concern worldwide. Noting of an excessive lung cancer risk among several groups of underground miners exposed to radon and its daughter products, studies on radon concentrations in the workplace and in dwellings have been conducted in many countries. The results have shown that the distribution of radon concentrations are approximately lognormal from which population weighted; the arithmetic mean of radon concentration of 40 Bq.m-3 has been adopted worldwide for dwellings and workplaces. The principal methods for reducing a high indoor radon concentration are: reducing the radon supply by reversing the pressure difference between the building and the soil; raising the resistance of the foundations to soil gas entry; removing the radon sources such as water or underlying soil; diluting the concentration by increasing the ventilation rate; and reducing the concentration of radon progeny by filtering and increasing the circulation of indoor air. Buildings which have a radon concentration higher than 200 Bq.m-3 should be investigated by the national authorities concerned; meanwhile, householders should be advised to take simple temporary precautions, such as increasing ventilation, until a permanent remedy can be effected.

  12. Indoor radon concentrations in the town of Niksic, Montenegro.

    PubMed

    Antovic, N; Vukotic, P; Zekic, R; Ilic, R

    2007-01-01

    Indoor radon was systematically surveyed in the town of Niksic-the second largest town in Montenegro-which has some of its settlements built above red bauxite deposits. The radon concentrations were measured in 55 homes in 2002/03, in the summer and winter period, using CR-39 etched track detectors. The average annual radon concentrations were found to be lognormally distributed (geometric mean = 66.2 Bq m(-3), geometric standard deviation = 3.0) within the range from 10 to 966 Bq m(-3), with arithmetic mean of 122.7 Bq m(-3) and median of 61.7 Bq m(-3). Although the annual mean radon concentrations above the action level of 400 Bq m(-3) are found only in four dwellings, the indoor radon levels in the town of Niksic are relatively high when compared with the average in the South European countries, as well as with indoor radon levels in other regions in Montenegro.

  13. Daily variations of indoor air-ion and radon concentrations.

    PubMed

    Kolarz, P M; Filipović, D M; Marinković, B P

    2009-11-01

    Air-ions and radon are two atmospheric trace constituents which have two opposite effects on human health: the ions are beneficial, and radon gas is potentially lethal as it increases the risk of lung cancer. In the lower troposphere, radon is the most important generator of the air-ions. Ionization by cosmic rays and radioactive minerals is almost constant in daily cycles, and variation of air-ion concentrations is attributed to changes of the radon activity. Air-ion and radon concentrations in outdoor and indoor space and their vertical gradients in residential buildings were measured. Gerdien type air-ion detector "CDI-06" made in our laboratory and radon monitor "RAD7" were utilized for these measurements. Correlation coefficient between positive air-ion and Rn indoor concentrations was approximately 0.7. Outdoor and indoor peak values were simultaneous while vertical gradient of concentrations in indoor measurements was evident. The indoor experiments showed that positive air-ion concentration could be an alternative method of radon activity concentration evaluation. PMID:19700332

  14. Problems with Estimating Annual Mean Indoor Radon Concentrations

    NASA Astrophysics Data System (ADS)

    Marušiaková, Miriam; Hůlka, Jińrí

    2010-09-01

    Radon and its progeny in dwellings is responsible for the majority of the total radiation dose among the general population. The indoor radon concentration varies considerably during the daytime, individual days, seasons and even years. It is affected by many factors such as ventilation, soil concentration, quality of house insulation and others. The annual mean value of the radon concentration in buildings is important in order to estimate the effective dose to inhabitants. However, it is not always possible to perform radon measurements over a period of one year. Thus estimates based on short-term continuous measurements are suggested. We analyse hourly radon measurements obtained from one uninhabited rural house in Telecí in the Czech Republic. We study the behaviour of the radon concentration with time and its relationship to meteorological variables such as outdoor temperature, wind speed or pressure. Further we discuss various estimates of the annual mean radon concentration and their properties.

  15. Problems with Estimating Annual Mean Indoor Radon Concentrations

    SciTech Connect

    Marusiakova, Miriam; Hulka, Jiri

    2010-09-30

    Radon and its progeny in dwellings is responsible for the majority of the total radiation dose among the general population. The indoor radon concentration varies considerably during the daytime, individual days, seasons and even years. It is affected by many factors such as ventilation, soil concentration, quality of house insulation and others.The annual mean value of the radon concentration in buildings is important in order to estimate the effective dose to inhabitants. However, it is not always possible to perform radon measurements over a period of one year. Thus estimates based on short-term continuous measurements are suggested.We analyse hourly radon measurements obtained from one uninhabited rural house in Teleci in the Czech Republic. We study the behaviour of the radon concentration with time and its relationship to meteorological variables such as outdoor temperature, wind speed or pressure. Further we discuss various estimates of the annual mean radon concentration and their properties.

  16. Bayesian Prediction of Mean Indoor Radon Concentrations for Minnesota Counties

    SciTech Connect

    Price, P.N.; Nero, A.V.; Gelman, A.

    1995-08-01

    Past efforts to identify areas having higher than average indoor radon concentrations by examining the statistical relationship between local mean concentrations and physical parameters such as the soil radium concentration have been hampered by the noise in local means caused by the small number of homes monitored in some or most areas, In the present paper, indoor radon data from a survey in Minnesota are analyzed in such a way as to minimize the effect of finite sample size within counties, in order to determine the true county-to-county variation of indoor radon concentrations in the state and the extent to which this variation is explained by the variation in surficial radium concentration among counties, The analysis uses hierarchical modeling, in which some parameters of interest (such as county geometric mean (GM) radon concentrations) are assumed to be drawn from a single population, for which the distributional parameters are estimated from the data. Extensions of this technique, known as a random effects regression and mixed effects regression, are used to determine the relationship between predictive variables and indoor radon concentrations; the results are used to refine the predictions of each county's radon levels, resulting in a great decrease in uncertainty. The true county-to-county variation of GM radon levels is found to be substantially less than the county-to-county variation of the observed GMs, much of which is due to the small sample size in each county. The variation in the logarithm of surficial radium content is shown to explain approximately 80% of the variation of the logarithm of GM radon concentration among counties. The influences of housing and measurement factors, such as whether the monitored home has a basement and whether the measurement was made in a basement, are also discussed. This approach offers a self-consistent statistical method for predicting the mean values of indoor radon concentrations or other geographically

  17. Measurement of Indoor Radon-222 and Radon-220 Concentrations in Central Japan

    SciTech Connect

    Oka, Mitsuaki; Shimo, Michikuni; Tokonami, Shinji; Sorimachi, Atsuyuki; Takahashi, Hiromichi; Ishikawa, Tetsuo

    2008-08-07

    A passive-type radon/thoron detector was used for measuring indoor radon and thoron concentrations at 90 dwellings in Aichi and Gifu prefectures in central Japan during 90 days from December, 2006 to March, 2007. The radon and thoron concentrations were 21.1 Bq/m3 and 25.1 Bq/m3, respectively. The dose due to radon and thoron in dwellings was roughly evaluated as 0.7 mSv/y and 2.4 mSv/y, respectively. The examination of the geological factor and house condition having an effect on indoor radon concentration was performed.

  18. Bayesian Prediction of Mean Indoor Radon Concentrations for Minnesota Counties

    SciTech Connect

    Price, P.N.; Nero, A.V.; Gelman, A.

    1996-02-01

    Past efforts to identify areas with higher than average indoor radon concentrations by examining the statistical relationship between local mean concentrations and physical parameters such as the soil radium concentration have been hampered by the variation in local means caused by the small number of homes monitored in most areas. In this paper, indoor radon data from a survey in Minnesota are analyzed to minimize the effect of finite sample size within counties, to determine the true county-to-county variation of indoor radon concentrations in the state, and to find the extent to which this variation is explained by the variation in surficial radium concentration among counties. The analysis uses hierarchical modeling, in which some parameters of interest (such as county geometric mean (GM) radon concentrations) are assumed to be drawn from a single population, for which the distributional parameters are estimated from the data. Extensions of this technique, known as a random effects regression and mixed effects regression, are used to determine the relationship between predictive variables and indoor radon concentrations; the results are used to refine the predictions of each county's radon levels, resulting in a great decrease in uncertainty. The true county-to-county variation of GM radon levels is found to be substantially less than the county-to-county variation of the observed GMs, much of which is due to the small sample size in each county. The variation in the logarithm of surficial radium content is shown to explain approximately 80% of the variation of the logarithm of GM radon concentration among counties. The influences of housing and measurement factors, such as whether the monitored home has a basement and whether the measurement was made in a basement, are also discussed. The statistical method can be used to predict mean radon concentrations, or applied to other geographically distributed environmental parameters.

  19. Variance of indoor radon concentration: Major influencing factors.

    PubMed

    Yarmoshenko, I; Vasilyev, A; Malinovsky, G; Bossew, P; Žunić, Z S; Onischenko, A; Zhukovsky, M

    2016-01-15

    Variance of radon concentration in dwelling atmosphere is analysed with regard to geogenic and anthropogenic influencing factors. Analysis includes review of 81 national and regional indoor radon surveys with varying sampling pattern, sample size and duration of measurements and detailed consideration of two regional surveys (Sverdlovsk oblast, Russia and Niška Banja, Serbia). The analysis of the geometric standard deviation revealed that main factors influencing the dispersion of indoor radon concentration over the territory are as follows: area of territory, sample size, characteristics of measurements technique, the radon geogenic potential, building construction characteristics and living habits. As shown for Sverdlovsk oblast and Niška Banja town the dispersion as quantified by GSD is reduced by restricting to certain levels of control factors. Application of the developed approach to characterization of the world population radon exposure is discussed. PMID:26409145

  20. Variance of indoor radon concentration: Major influencing factors.

    PubMed

    Yarmoshenko, I; Vasilyev, A; Malinovsky, G; Bossew, P; Žunić, Z S; Onischenko, A; Zhukovsky, M

    2016-01-15

    Variance of radon concentration in dwelling atmosphere is analysed with regard to geogenic and anthropogenic influencing factors. Analysis includes review of 81 national and regional indoor radon surveys with varying sampling pattern, sample size and duration of measurements and detailed consideration of two regional surveys (Sverdlovsk oblast, Russia and Niška Banja, Serbia). The analysis of the geometric standard deviation revealed that main factors influencing the dispersion of indoor radon concentration over the territory are as follows: area of territory, sample size, characteristics of measurements technique, the radon geogenic potential, building construction characteristics and living habits. As shown for Sverdlovsk oblast and Niška Banja town the dispersion as quantified by GSD is reduced by restricting to certain levels of control factors. Application of the developed approach to characterization of the world population radon exposure is discussed.

  1. Reconstruction of national distribution of indoor radon concentration in Russia using results of regional indoor radon measurement programs.

    PubMed

    Yarmoshenko, I; Malinovsky, G; Vasilyev, A; Zhukovsky, M

    2015-12-01

    The aim of the paper is a reconstruction of the national distribution and estimation of the arithmetic average indoor radon concentration in Russia using the data of official annual 4-DOZ reports. Annual 4-DOZ reports summarize results of radiation measurements in 83 regions of Russian Federation. Information on more than 400,000 indoor radon measurements includes the average indoor radon isotopes equilibrium equivalent concentration (EEC) and number of measurements by regions and by three main types of houses: wooden, one-storey non-wooden, and multi-storey non-wooden houses. To reconstruct the national distribution, all-Russian model sample was generated by integration of sub-samples created using the results of each annual regional program of indoor radon measurements in each type of buildings. According to indoor radon concentration distribution reconstruction, all-Russian average indoor radon concentration is 48 Bq/m(3). Average indoor radon concentration by region ranges from 12 to 207 Bq/m(3). The 95-th percentile of the distribution is reached at indoor radon concentration 160 Bq/m(3). PMID:26313426

  2. Reconstruction of national distribution of indoor radon concentration in Russia using results of regional indoor radon measurement programs.

    PubMed

    Yarmoshenko, I; Malinovsky, G; Vasilyev, A; Zhukovsky, M

    2015-12-01

    The aim of the paper is a reconstruction of the national distribution and estimation of the arithmetic average indoor radon concentration in Russia using the data of official annual 4-DOZ reports. Annual 4-DOZ reports summarize results of radiation measurements in 83 regions of Russian Federation. Information on more than 400,000 indoor radon measurements includes the average indoor radon isotopes equilibrium equivalent concentration (EEC) and number of measurements by regions and by three main types of houses: wooden, one-storey non-wooden, and multi-storey non-wooden houses. To reconstruct the national distribution, all-Russian model sample was generated by integration of sub-samples created using the results of each annual regional program of indoor radon measurements in each type of buildings. According to indoor radon concentration distribution reconstruction, all-Russian average indoor radon concentration is 48 Bq/m(3). Average indoor radon concentration by region ranges from 12 to 207 Bq/m(3). The 95-th percentile of the distribution is reached at indoor radon concentration 160 Bq/m(3).

  3. Predictors of Indoor Radon Concentrations in Pennsylvania, 1989–2013

    PubMed Central

    Casey, Joan A.; Ogburn, Elizabeth L.; Rasmussen, Sara G.; Irving, Jennifer K.; Pollak, Jonathan; Locke, Paul A.

    2015-01-01

    Background Radon is the second-leading cause of lung cancer worldwide. Most indoor exposure occurs by diffusion of soil gas. Radon is also found in well water, natural gas, and ambient air. Pennsylvania has high indoor radon concentrations; buildings are often tested during real estate transactions, with results reported to the Department of Environmental Protection (PADEP). Objectives We evaluated predictors of indoor radon concentrations. Methods Using first-floor and basement indoor radon results reported to the PADEP between 1987 and 2013, we evaluated associations of radon concentrations (natural log transformed) with geology, water source, building characteristics, season, weather, community socioeconomic status, community type, and unconventional natural gas development measures based on drilled and producing wells. Results Primary analysis included 866,735 first measurements by building, with the large majority from homes. The geologic rock layer on which the building sat was strongly associated with radon concentration (e.g., Axemann Formation, median = 365 Bq/m3, IQR = 167–679 vs. Stockton Formation, median = 93 Bq/m3, IQR = 52–178). In adjusted analysis, buildings using well water had 21% higher concentrations (β = 0.191, 95% CI: 0.184, 0.198). Buildings in cities (vs. townships) had lower concentrations (β = –0.323, 95% CI: –0.333, –0.314). When we included multiple tests per building, concentrations declined with repeated measurements over time. Between 2005 and 2013, 7,469 unconventional wells were drilled in Pennsylvania. Basement radon concentrations fluctuated between 1987 and 2003, but began an upward trend from 2004 to 2012 in all county categories (p < 0.001), with higher levels in counties having ≥ 100 drilled wells versus counties with none, and with highest levels in the Reading Prong. Conclusions Geologic unit, well water, community, weather, and unconventional natural gas development were associated with indoor radon

  4. Measurement of indoor radon concentration in kindergartens in Sofia, Bulgaria.

    PubMed

    Ivanova, Kremena; Stojanovska, Zdenka; Tsenova, Martina; Badulin, Viktor; Kunovska, Bistra

    2014-11-01

    As a part of the systematic survey of indoor radon in Bulgaria, the indoor radon concentration was measured in 296 kindergarten buildings of Sofia city during 3 months (February to April 2013) using the CR-39 nuclear tract detectors. In 256 buildings at least two frequently occupied rooms (mainly playrooms) were observed. Altogether, 922 measurements were performed. The frequency distribution was well described by the lognormal function. The measured radon concentrations range between 9 and 1415 Bq m(-3) with a geometric mean of 101 Bq m(-3) (2.08) and an arithmetic mean 132 Bq m(-3) with a standard deviation of 118 Bq m(-3). The radon concentrations obtained in this survey were compared with that in Sofia city dwellings obtained from a previous study. A detailed statistical analysis of the building factors was presented.

  5. Indoor Radon Concentration Levels in Najran Region, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Alyami, S. H.; Al-Ghamdi, S. S.; Baig, M. R.; Al-Garawi, M. S.

    2010-07-01

    Measurement of indoor radon concentration was performed in Najran region in the south west of Saudi Arabia, using CR-39 dosimeter. Despite many previous studies on indoor radon concentrations in Saudi Arabia, the data available are still limited. The objective of this study, which is the first of its kind in the region, is to have preliminary data of radon in this region. Such measurement will contribute towards further studies in this region of Saudi Arabia. The indoor radon concentration was measured in the villages of Fara Al-Jabal and Badr Al-Janoob (about 2000 m above sea level), Hadadah and Al-Khanig (about 1700 m above sea level). It was found that radon distribution in these villages is normal skewed to the right, with a range of 9±5 to 163±32 Bqm-3 and an average of 49±2 Bqm-3. It was also found that the average radon concentration is independent of altitude. Our findings show that the values are below the safe limit of 150 Bqm-3 set by the Environmental Protection Agency (EPA) of the USA

  6. Indoor Radon Concentration Levels in Najran Region, Saudi Arabia

    SciTech Connect

    Alyami, S. H.; Al-Ghamdi, S. S.; Baig, M. R.; Al-Garawi, M.S.

    2010-07-07

    Measurement of indoor radon concentration was performed in Najran region in the south west of Saudi Arabia, using CR-39 dosimeter. Despite many previous studies on indoor radon concentrations in Saudi Arabia, the data available are still limited. The objective of this study, which is the first of its kind in the region, is to have preliminary data of radon in this region. Such measurement will contribute towards further studies in this region of Saudi Arabia. The indoor radon concentration was measured in the villages of Fara Al-Jabal and Badr Al-Janoob (about 2000 m above sea level), Hadadah and Al-Khanig (about 1700 m above sea level). It was found that radon distribution in these villages is normal skewed to the right, with a range of 9{+-}5 to 163{+-}32 Bqm{sup -3} and an average of 49{+-}2 Bqm{sup -3}. It was also found that the average radon concentration is independent of altitude. Our findings show that the values are below the safe limit of 150 Bqm{sup -3} set by the Environmental Protection Agency (EPA) of the USA

  7. Correlation of indoor radon concentration to commonly available geologic data

    NASA Astrophysics Data System (ADS)

    Burkhart, James F.; Huber, Thomas P.

    1993-03-01

    Over the last several years, the inhalation of decay products coming from radon-222 has become a national health concern. It is estimated that somewhere between 16,000 and 20,000 people die annually in the United States from lung cancer due to exposure to these decay products. Nationwide, 95% of all homes have not been tested for radon, and so it would seem that any methodology that could give a general idea of indoor radon concentrations (without actually testing the house itself) might be useful. While not intended to replace a radon test, which is both simple and inexpensive, our project attempts to predict indoor radon concentrations based on easily obtainable information from Soil Conservation Service county soil surveys and US Geological Survey surficial geology maps. We have chosen four parameters: soil permeability, surficial geology, soil shrink-swell potential, and distance to the nearest geologic fault. Of these four variables, surficial geology and distance to fault correlated well to winter indoor radon concentrations as measured by short-term (48-h) tests. While it is understood that there are limits to this methodology, primarily because of map scale problems, the correlations mentioned above were very strong and suggest further study would be useful.

  8. Factors affecting indoor radon concentration in Norwegian homes

    SciTech Connect

    Strand, T.

    1995-12-31

    The indoor radon concentration may vary by more than an order of magnitude over a few days period, and often there is a significant difference in the radon level between summer and winter. The variation pattern gives important information about the source characteristics which is often needed when remedial measures are introduced. Short-term and long-term variations of the radon concentration in twenty typical Norwegian single family houses were studied in detail by continuous measurements and monthly passive measurements by nuclear track detectors. The radon measurements were correlated with meteorological data, building characteristics and information from the householders about ventilation habits. The main results of these studies will be presented in this paper.

  9. An integrated compartmental model for prediction of indoor radon concentrations

    SciTech Connect

    Al-Ahmady, K.K.; Hintenlang, D.E.

    1995-12-31

    A carefully selected, heavily instrumented, and fully controlled experimental facility dedicated to research was used to investigate the interaction and effects of key parameters related to the indoor radon problem. Mechanistic and empirical models have been developed in which they return pressure differentials in response to indoor radon driving forces inputs. A semi-diurnal natural pumping model of radon-rich soil gas was based on an exponentially damped response of the sub-slab air volume pressure to changes in atmospheric pressure. A wind-induced pressure differentials model was based on the conservation of energy of the wind speed between the main stream and the structure shell corrected to the effect of wind fluctuation and direction. A temperature-induced pressure differential model was based on the linear approximation of the weakly exponentially-dependent pressures between two temperature zones under hydrostatic equilibrium. Mathematical frameworks were developed to incorporate driving force models into an integrated compartmental model allowed predictions of time-integrated and time-dependent indoor radon concentrations. The integrated predictions are in good agreement with the observed concentrations at the research site.

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

    PubMed

    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. Unusually high indoor radon concentrations from a giant rock slide.

    PubMed

    Ennemoser, O; Ambach, W; Brunner, P; Schneider, P; Oberaigner, W; Purtscheller, F; Stingl, V; Keller, G

    1994-07-18

    In a village in western Tyrol, Austria (Umhausen, approximately 2600 inhabitants) unusually high indoor radon concentrations were measured. The medians were found to be 3750 Bq/m3 (basements) and 1160 Bq/m3 (ground floors) in winter, and 361 Bq/m3 (basements) and 210 Bq/m3 (ground floors) in summer. Maximum radon concentrations of up to 274,000 Bq/m3 were registered. The unusually high radon concentrations are due to the geology of the locality. The part of Umhausen with the highest radon concentrations is built on an alluvial fan of a giant rock slide (granitic gneiss). Measurements of the radon exhalation rate from soil showed a median of 0.4 Bq/m2/s, measurements of the radium content of rock samples yielded a median of 125 Bq/kg. The material of the rock slide is heavily fractured so that an elevated emanating power and an increased diffusion coefficient for radon in soil must be assumed. Given a diffusion coefficient of 8 x 10(-6) m2/s and an emanating power of 0.3, the median exhalation rate of 0.4 Bq/m2/s is obtained at a radium concentration of 125 Bq/kg. The rock slide is therefore considered to be the main source of radon. The abnormally high radon concentrations in Umhausen coincide with a statistically significant increase in lung cancer mortality (age and sex standardized mortality rate = 3.9, 95% C.I.: 2.9-5.1); the control population is the population of the entire Tyrol (630,000 inhabitants). PMID:8085147

  12. Estimating the radon concentration in water and indoor air.

    PubMed

    Maged, A F

    2009-05-01

    The paper presents the results of radon concentration measurements in the vicinity of water, indoor air and in contact to building walls. The investigations were carried out using CR-39 track detectors. Samples of ground water flowing out of many springs mostly in Arabian Gulf area except one from Germany have been studied. The results are compared with international recommendations and the values are found to be lower than the recommended value. Measuring the mean indoor radon concentrations in air and in contact to building walls in the dwellings of Kuwait University Campus were found 24.2 +/- 7.7, and 462 +/- 422 Bq m(-3) respectively. These values lead to average effective dose equivalent rates of 1.3 +/- 0.4 and 23 +/- 21 mSv year(-1), respectively.

  13. An investigation of the potential causes for the seasonal and annual variations in indoor radon concentrations.

    PubMed

    Barazza, F; Gfeller, W; Palacios, M; Murith, C

    2015-11-01

    Indoor radon concentrations exhibit strong variations on short and long timescales. Besides human influences, meteorological factors significantly affect the radon concentrations indoors as well as outdoors. In this article, long-term measurements showing strong annual variations are presented, which take a very similar course in different buildings located in largely separated regions in Switzerland. Also, seasonal variations can be very significant. In general, variations in indoor radon levels can primarily be attributed to human influences. On the other hand, specific weather conditions can have a significant impact on indoor radon levels. In order to further investigate the connection between indoor radon levels and meteorological factors, a measuring campaign has been started in two buildings located in two different regions in Switzerland exhibiting different climatic characteristics. Preliminary results of these investigations are presented, which provide evidence for correlations between indoor radon levels and in particular outdoor temperatures, contributing to seasonal and annual as well as short-term variations in indoor radon concentrations.

  14. Indoor radon concentration in geothermal areas of central Italy.

    PubMed

    Ciolini, R; Mazed, D

    2010-09-01

    The indoor radon ((222)Rn) activity concentration was measured between January and June in the schools of two geothermal areas in Tuscany, central Italy. One of these areas (the Larderello area) is characterized by a large number of geothermal power plants, covering about 9% of the world's geothermal power production. In contrast, the other area, Monte Pisano, has not any such facilities. About 250 measurements were made using track etch detectors. Only a slight difference in the concentrations between the two major sampling areas (98 Bq m(-3) for Larderello area and 43 Bq m(-3) for Monte Pisano area) was found, and this was related to different geological characteristics of the ground and not the presence of the geothermal plants. The measured radon concentrations were always well below the intervention levels in both areas, and health risks for students and personnel in the examined schools were excluded.

  15. Variation of indoor radon concentration and ambient dose equivalent rate in different outdoor and indoor environments.

    PubMed

    Stojanovska, Zdenka; Boev, Blazo; Zunic, Zora S; Ivanova, Kremena; Ristova, Mimoza; Tsenova, Martina; Ajka, Sorsa; Janevik, Emilija; Taleski, Vaso; Bossew, Peter

    2016-05-01

    Subject of this study is an investigation of the variations of indoor radon concentration and ambient dose equivalent rate in outdoor and indoor environments of 40 dwellings, 31 elementary schools and five kindergartens. The buildings are located in three municipalities of two, geologically different, areas of the Republic of Macedonia. Indoor radon concentrations were measured by nuclear track detectors, deployed in the most occupied room of the building, between June 2013 and May 2014. During the deploying campaign, indoor and outdoor ambient dose equivalent rates were measured simultaneously at the same location. It appeared that the measured values varied from 22 to 990 Bq/m(3) for indoor radon concentrations, from 50 to 195 nSv/h for outdoor ambient dose equivalent rates, and from 38 to 184 nSv/h for indoor ambient dose equivalent rates. The geometric mean value of indoor to outdoor ambient dose equivalent rates was found to be 0.88, i.e. the outdoor ambient dose equivalent rates were on average higher than the indoor ambient dose equivalent rates. All measured can reasonably well be described by log-normal distributions. A detailed statistical analysis of factors which influence the measured quantities is reported. PMID:26943159

  16. A mathematical approach for predicting long-term indoor radon concentrations from short-term measurements

    SciTech Connect

    Al-Ahmady, K.K.; Hintenlang, D.E.

    1995-12-31

    Assessment of long-term radon concentrations from short-term testing results are of significant importance when radon risk assessment and liability issues are considered. These issues are based on the figure of annual exposure to indoor radon while radon measurement practices are mainly followed the EPA short-term testing protocols. A mathematical framework has been developed that facilities non-statistical approach to construct the relationship between the short-term indoor radon measurements and the long term annual indoor radon levels. This approach was based on the application of the time-dependent indoor radon concentrations calculated from the corresponding contributions of indoor radon driving forces for different time periods having a reference starting time. The approach utilizes an analytical procedure that is based on the solutions of the mass balance equation for the radon gas in the indoor environment. The solutions are applied through semi-analytical modeling of time-dependent indoor radon concentrations. This treatment provides a powerful tool and procedure to assess long-term indoor radon concentrations from short-term testing results.

  17. Influence of indoor air conditions on radon concentration in a detached house.

    PubMed

    Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

    2013-02-01

    Radon is released from soil and building materials and can accumulate in residential buildings. Breathing radon and radon progeny for extended periods hazardous to health and can lead to lung cancer. Indoor air conditions and ventilation systems strongly influence indoor radon concentrations. This paper focuses on effects of air change rate, indoor temperature and relative humidity on indoor radon concentrations in a one family detached house in Stockholm, Sweden. In this study a heat recovery ventilation system unit was used to control the ventilation rate and a continuous radon monitor (CRM) was used to measure radon levels. FLUENT, a computational fluid dynamics (CFD) software package was used to simulate radon entry into the building and air change rate, indoor temperature and relative humidity effects using a numerical approach. The results from analytical solution, measurements and numerical simulations showed that air change rate, indoor temperature and moisture had significant effects on indoor radon concentration. Increasing air change rate reduces radon level and for a specific air change rate (in this work Ach = 0.5) there was a range of temperature and relative humidity that minimized radon levels. In this case study minimum radon levels were obtained at temperatures between 20 and 22 °C and a relative humidity of 50-60%.

  18. Influence of indoor air conditions on radon concentration in a detached house.

    PubMed

    Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

    2013-02-01

    Radon is released from soil and building materials and can accumulate in residential buildings. Breathing radon and radon progeny for extended periods hazardous to health and can lead to lung cancer. Indoor air conditions and ventilation systems strongly influence indoor radon concentrations. This paper focuses on effects of air change rate, indoor temperature and relative humidity on indoor radon concentrations in a one family detached house in Stockholm, Sweden. In this study a heat recovery ventilation system unit was used to control the ventilation rate and a continuous radon monitor (CRM) was used to measure radon levels. FLUENT, a computational fluid dynamics (CFD) software package was used to simulate radon entry into the building and air change rate, indoor temperature and relative humidity effects using a numerical approach. The results from analytical solution, measurements and numerical simulations showed that air change rate, indoor temperature and moisture had significant effects on indoor radon concentration. Increasing air change rate reduces radon level and for a specific air change rate (in this work Ach = 0.5) there was a range of temperature and relative humidity that minimized radon levels. In this case study minimum radon levels were obtained at temperatures between 20 and 22 °C and a relative humidity of 50-60%. PMID:23159846

  19. Radon in indoor concentrations and indoor concentrations of metal dust particles in museums and other public buildings.

    PubMed

    Carneiro, G L; Braz, D; de Jesus, E F; Santos, S M; Cardoso, K; Hecht, A A; Dias da Cunha, Moore K

    2013-06-01

    The aim of this study was to evaluate the public and occupational exposure to radon and metal-bearing particles in museums and public buildings located in the city of Rio de Janeiro, Brazil. For this study, four buildings were selected: two historic buildings, which currently house an art gallery and an art museum; and two modern buildings, a chapel and a club. Integrated radon concentration measurements were performed using passive radon detectors with solid state nuclear track detector-type Lexan used as nuclear track detector. Air samplers with a cyclone were used to collect the airborne particle samples that were analyzed by the particle-induced X-ray emission technique. The average unattached-radon concentrations in indoor air in the buildings were above 40 Bq/m(3), with the exception of Building D as measured in 2009. The average radon concentrations in indoor air in the four buildings in 2009 were below the recommended reference level by World Health Organization (100 Bq/m(3)); however, in 2011, the average concentrations of radon in Buildings A and C were above this level, though lower than 300 Bq/m(3). The average concentrations of unattached radon were lower than 148 Bq/m(3) (4pCi/L), the USEPA level recommended to take action to reduce the concentrations of radon in indoor air. The unattached-radon average concentrations were also lower than the value recommended by the European Union for new houses. As the unattached-radon concentrations were below the international level recommended to take action to reduce the radon concentration in air, it was concluded that during the period of sampling, there was low risk to human health due to the inhalation of unattached radon in these four buildings.

  20. Indoor Radon Measurement in Van

    NASA Astrophysics Data System (ADS)

    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.

  1. Indoor Radon Measurement in Van

    SciTech Connect

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

    2007-04-23

    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.

  2. Indoor Radon and Its Decay Products: Concentrations, Causes, and Control Strategies

    SciTech Connect

    Nero, A.V.; Gadgil, A.J.; Nazaroff, W.W.; Revzan, K.L.

    1990-01-01

    This report is an introduction to the behavior of radon 222 and its decay products in indoor air. This includes review of basic characteristics of radon and its decay products and of features of the indoor environment itself, all of which factors affect behavior in indoor air. The experimental and theoretical evidence on behavior of radon and its decay products is examined, providing a basis for understanding the influence of geological, structural, and meteorological factors on indoor concentrations, as well as the effectiveness of control techniques. We go on to examine three important issues concerning indoor radon. We thus include (1) an appraisal of the concentration distribution in homes, (2) an examination of the utility and limitations of popular monitoring techniques and protocols, and (3) an assessment of the key elements of strategies for controlling radon levels in homes.

  3. Anomalous indoor radon concentration in a dwelling in Qatif City, Saudi Arabia.

    PubMed

    Al-Jarallah, M I; Fazal-ur-Rehman

    2005-01-01

    An indoor radon survey was carried out recently in nine cities of Saudi Arabia using nuclear track detectors (NTD)-based passive radon detectors. The survey included Qatif City in the Eastern Province of Saudi Arabia, where 225 detectors were collected back successfully. It was found that the average indoor radon concentration in the dwellings was 22 +/- 15 Bq m(-3). However, one of the dwellings showed an anomalous radon concentration of 535 +/- 23 Bq m(-3). This finding led to a detailed investigation of this dwelling using active and passive techniques. In the active technique, an AlphaGUARD 2000 PRQ radon gas analyser was used. In the passive technique, CR-39 based passive radon detectors were used in all the rooms of the dwelling. Radon exhalation from the wall and the floor was also measured using the can technique. The active measurement confirms the passive one. Before placing the passive radon detectors in all the rooms of the two-storey building, the inhabitant was advised to ventilate his house regularly. The radon concentration in the different rooms was found to vary from 124 to 302 Bq m(-3). Radon exhalation from the floor and the wall of the room with the anomalous radon concentration was found to vary from 0.5 to 0.8 Bq m(-2) h(-1). These low radon exhalation rates suggest that the anomalous radon concentration is most probably due to underground radon diffusion into the dwelling through cracks and joints in the concrete floor.

  4. Anomalous indoor radon concentration in a dwelling in Qatif City, Saudi Arabia.

    PubMed

    Al-Jarallah, M I; Fazal-ur-Rehman

    2005-01-01

    An indoor radon survey was carried out recently in nine cities of Saudi Arabia using nuclear track detectors (NTD)-based passive radon detectors. The survey included Qatif City in the Eastern Province of Saudi Arabia, where 225 detectors were collected back successfully. It was found that the average indoor radon concentration in the dwellings was 22 +/- 15 Bq m(-3). However, one of the dwellings showed an anomalous radon concentration of 535 +/- 23 Bq m(-3). This finding led to a detailed investigation of this dwelling using active and passive techniques. In the active technique, an AlphaGUARD 2000 PRQ radon gas analyser was used. In the passive technique, CR-39 based passive radon detectors were used in all the rooms of the dwelling. Radon exhalation from the wall and the floor was also measured using the can technique. The active measurement confirms the passive one. Before placing the passive radon detectors in all the rooms of the two-storey building, the inhabitant was advised to ventilate his house regularly. The radon concentration in the different rooms was found to vary from 124 to 302 Bq m(-3). Radon exhalation from the floor and the wall of the room with the anomalous radon concentration was found to vary from 0.5 to 0.8 Bq m(-2) h(-1). These low radon exhalation rates suggest that the anomalous radon concentration is most probably due to underground radon diffusion into the dwelling through cracks and joints in the concrete floor. PMID:15944144

  5. Dependence of indoor radon concentration on the year of house construction

    SciTech Connect

    Fujimoto, K.; Sanada, T.

    1999-10-01

    The dependence of indoor radon concentration on the year of house construction was studied using the results of two nationwide indoor radon surveys in Japan. The data of radon concentration in the surveys were classified into structure type as well as year of construction to obtain the current radon concentration for each structure type as a function of year of construction. The indoor radon concentration in wooden houses was found to be relatively constant with year of house construction until 1960, and then decreased, whereas the radon concentration in concrete houses increased sharply in houses constructed after 1970. The concentration in concrete houses built before 1975 was almost the same as that in contemporary wooden houses. However, the concentration in concrete houses built at present was about two times higher than that in wooden houses. The time trends found for wooden and concrete houses in the first nationwide indoor radon survey were confirmed by the second nationwide survey. In addition, these same time trends were mostly observed in the data classified into 7 districts in Japan. The increase of indoor radon concentration in concrete houses provides relatively high dose, and this increasing trend seems to continue, judging from the results of two nationwide surveys.

  6. Procedure for the characterization of radon potential in existing dwellings and to assess the annual average indoor radon concentration.

    PubMed

    Collignan, Bernard; Powaga, Emilie

    2014-11-01

    Risk assessment due to radon exposure indoors is based on annual average indoor radon activity concentration. To assess the radon exposure in a building, measurement is generally performed during at least two months during heating period in order to be representative of the annual average value. This is because radon presence indoors could be very variable during time. This measurement protocol is fairly reliable but may be a limiting in the radon risk management, particularly during a real estate transaction due to the duration of the measurement and the limitation of the measurement period. A previous field study defined a rapid methodology to characterize radon entry in dwellings. The objective of this study was at first, to test this methodology in various dwellings to assess its relevance with a daily test. At second, a ventilation model was used to assess numerically the air renewal of a building, the indoor air quality all along the year and the annual average indoor radon activity concentration, based on local meteorological conditions, some building characteristics and in-situ characterization of indoor pollutant emission laws. Experimental results obtained on thirteen individual dwellings showed that it is generally possible to obtain a representative characterization of radon entry into homes. It was also possible to refine the methodology defined in the previous study. In addition, numerical assessments of annual average indoor radon activity concentration showed generally a good agreement with measured values. These results are encouraging to allow a procedure with a short measurement time to be used to characterize long-term radon potential in dwellings. PMID:25011073

  7. Procedure for the characterization of radon potential in existing dwellings and to assess the annual average indoor radon concentration.

    PubMed

    Collignan, Bernard; Powaga, Emilie

    2014-11-01

    Risk assessment due to radon exposure indoors is based on annual average indoor radon activity concentration. To assess the radon exposure in a building, measurement is generally performed during at least two months during heating period in order to be representative of the annual average value. This is because radon presence indoors could be very variable during time. This measurement protocol is fairly reliable but may be a limiting in the radon risk management, particularly during a real estate transaction due to the duration of the measurement and the limitation of the measurement period. A previous field study defined a rapid methodology to characterize radon entry in dwellings. The objective of this study was at first, to test this methodology in various dwellings to assess its relevance with a daily test. At second, a ventilation model was used to assess numerically the air renewal of a building, the indoor air quality all along the year and the annual average indoor radon activity concentration, based on local meteorological conditions, some building characteristics and in-situ characterization of indoor pollutant emission laws. Experimental results obtained on thirteen individual dwellings showed that it is generally possible to obtain a representative characterization of radon entry into homes. It was also possible to refine the methodology defined in the previous study. In addition, numerical assessments of annual average indoor radon activity concentration showed generally a good agreement with measured values. These results are encouraging to allow a procedure with a short measurement time to be used to characterize long-term radon potential in dwellings.

  8. Characterization of radon entry rates and indoor concentrations in underground structures

    SciTech Connect

    Borak, T.B.; Whicker, F.W.; Fraley, L.; Gadd, M.S.; Ibrahim, S.A.; Monette, F.A.; Morris, R.; Ward, D.C.

    1992-12-31

    An experimental facility has been designed to comprehensively determine the influence of soil and meterological conditions on the transport of radon into underground structures. Two identical basements are equipped to continuously monitor pressure differentials, temperatures, soil moisture, precipitation, barometric pressure, wind speed, wind direction, natural ventiliation rates, and radon concentrations. A computerized data acquisition system accumulates and processes data at the rate of 6000 points per day. The experimental design is based on performing experiments in one structure, with the other used as a control. Indoor radon concentrations have temporal variations ranging from 150 to 1400 Bq m{sup -3}. The corresponding entry rate of radon ranges from 300 to 10,000 Bq h{sup -1}. When the radon entry rate is high, the indoor radon concentration decreases, whereas elevated radon concentrations seem to be associated with slow but persistent radon entry rates. This inverse relationship is partially due to compensation from enhanced natural ventilation during periods when the radon entry rate is high. Correlations between measured variables in the soil and indoor-outdoor atmospheres are used to interpret these data. This laboratory has the capability to generate essential data required for developing and testing radon transport models.

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

    PubMed

    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.

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

    PubMed

    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. PMID:25920786

  11. Correction factors for determination of annual average radon concentration in dwellings of Poland resulting from seasonal variability of indoor radon.

    PubMed

    Kozak, K; Mazur, J; Kozłowska, B; Karpińska, M; Przylibski, T A; Mamont-Cieśla, K; Grządziel, D; Stawarz, O; Wysocka, M; Dorda, J; Zebrowski, A; Olszewski, J; Hovhannisyan, H; Dohojda, M; Kapała, J; Chmielewska, I; Kłos, B; Jankowski, J; Mnich, S; Kołodziej, R

    2011-10-01

    The method for the calculation of correction factors is presented, which can be used for the assessment of the mean annual radon concentration on the basis of 1-month or 3-month indoor measurements. Annual radon concentration is an essential value for the determination of the annual dose due to radon inhalation. The measurements have been carried out in 132 houses in Poland over a period of one year. The passive method of track detectors with CR-39 foil was applied. Four thermal-precipitation regions in Poland were established and correction factors were calculated for each region, separately for houses with and without basements.

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

    NASA Astrophysics Data System (ADS)

    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. Prediction of indoor radon concentration based on residence location and construction

    SciTech Connect

    Maekelaeinen, I.; Voutilainen, A.; Castren, O.

    1992-12-31

    We have constructed a model for assessing indoor radon concentrations in houses where measurements cannot be performed. It has been used in an epidemiological study and to determine the radon potential of new building sites. The model is based on data from about 10,000 buildings. Integrated radon measurements were made during the cold season in all the houses; their geographic coordinates were also known. The 2-mo measurement results were corrected to annual average concentrations. Construction data were collected from questionnaires completed by residents; geological data were determined from geological maps. Data were classified according to geographical, geological, and construction factors. In order to describe different radon production levels, the country was divided into four zones. We assumed that the factors were multiplicative, and a linear concentration-prediction model was used. The most significant factor in determining radon concentration was the geographical region, followed by soil type, year of construction, and type of foundation. The predicted indoor radon concentrations given by the model varied from 50 to 440 Bq m{sup -3}. The lower figure represents a house with a basement, built in the 1950s on clay soil, in the region with the lowest radon concentration levels. The higher value represents a house with a concrete slab in contact with the ground, built in the 1980s, on gravel, in the region with the highest average radon concentration.

  14. Preliminary Results of Indoor Radon/thoron Concentrations and Terrestrial Gamma Doses in Gejiu, Yunnan, China

    SciTech Connect

    Ishikawa, Tetsuo; Tokonami, Shinji; Kobayashi, Yosuke; Yoshinaga, Shinji; Sun Quafu; Min Xiangdong

    2008-08-07

    A preliminary survey on indoor radon/thoron and external gamma ray dose rate was conducted for houses in Gejiu city and its neighboring village in Yunnan Province, China. As a result of the radon/thoron measurements for about 50 houses, very high thoron concentrations were found in some hoses (maximum: 7,900 Bq/m{sup 3}). The mean annual dose from thoron decay products was estimated to be larger than that from radon decay products (2.9 mSv vs. 1.6 mSv). Further dosimetric and epidemiological studies are needed to investigate the possible effects of radon and thoron.

  15. Indoor radon concentration data: Its geographic and geologic distribution, an example from the Capital District, NY

    SciTech Connect

    Thomas, J.J.; Overeynder, H.M.; Thomas, B.R.

    1995-09-01

    Most studies of the geographic distribution of indoor radon levels are plotted by county or ZIP code. This method is used for the radon potential maps produced by the U.S. Environmental Protection Agency (EPA) and the New York State Department of Health (NYSDOH). The basis for the mapping is the mean or median indoor radon count for all the data provided by NYSDOH within each geographic area. While testing the indoor radon analyses provided to the authors by CMT Independent Laboratories, we discovered data that deviated markedly from the EPA and NYSDOH means for the Capital District of New York (Albany and surrounding counties). Their screening indoor radon average concentrations in pCi/L, indicate low potential for Schenectady (3.0), Saratoga (3.2), and Albany (3.7) counties; and moderate potential for Rensselaer (6.4) and Columbia (7.0) counties. Our database of over 3,000 analyses contains over 800 records of indoor radon counts above 4 pCi/L (14-47% of each county`s analyses), many high enough to be rated as a serious health hazard. In order to obtain greater precision of information, the authors plotted their indoor radon data by street address using MapInfo, a geographic Information System (GIS), and StreetInfo, MapInfo`s TIGER address database. We compared the geographic distribution of our data to both the Bedrock Geology and Surficial Geology Maps of New York State. The results show a striking relationship of radon concentrations to bedrock, faults and permeability of surficial material. Data being compiled and mapped by street address by the NYSDOH in Erie County in western New York, confirm our results.

  16. Indoor radon concentration measurement in the dwellings of district Poonch (Azad Kashmir), Pakistan.

    PubMed

    Rafique, Muhammad; Rahman, Said; Rahman, S U; Jabeen, Shahida; Shahzad, M Ikram; Rathore, Mumtaz H; Matiullah

    2010-02-01

    The present study deals with measurement of indoor radon concentrations in dwellings of the district Poonch of the state of Azad Jammu and Kashmir, Pakistan. In this context, CR-39-based box-type radon detectors were installed in drawing rooms and bedrooms of 80 selected houses and were exposed to indoor radon for 3 months. After exposure, the CR-39 detectors were etched for 9 h in 6 mol NaOH at 70 degrees C and the observed track densities were related to radon concentrations. Measured indoor radon concentrations in the studied area ranged from 27 +/- 6 to 169 +/- 4, 29 +/- 6 to 196 +/- 4 and 31 +/- 5 to 142 +/- 2 Bq m(-3) in the drawing rooms and 74 +/- 5 to 172 +/- 3, 32 +/- 6 to 191 +/- 4 and 27 +/- 5 to 155 +/- 2 Bq m(-3) in bedrooms of the Abbaspur, Hajira and Rawalakot regions of the district Poonch, respectively; whereas weighted average radon concentration ranged from 93 +/- 6 to 159 +/- 4, 33 +/- 5 to 118 +/- 3 and 31 +/- 6 to 155 +/- 5 Bq m(-3) in the dwellings of Abbaspur, Hajira and Rawalakot, respectively. Estimated doses due to the indoor radon ranged from 2.35 +/- 0.15 to 4.00 +/- 0.10, 0.83 +/- 0.08 to 2.98 +/- 0.08 and 0.78 +/- 0.15 to 3.91 +/- 0.13 mSv y(-1) for Abbaspur, Rawalakot and Hajira, respectively. Comparing the current indoor radon results with those of the Health Protection Agency UK and US EPA (i.e. 200 and 148 Bq m(-3)) limits, majority of the houses surveyed in the present study are within the safe limits.

  17. Assessment of indoor radon concentration in phosphate fertilizer warehouses in Nigeria

    NASA Astrophysics Data System (ADS)

    Okeji, Mark C.; Agwu, Kenneth K.

    2012-03-01

    Indoor radon concentration level was measured in twelve selected phosphate fertilizer warehouses in Nigeria in order to establish potential hazards to persons using such warehouses as offices. The fertilizer warehouses were selected based on the brand of fertilizers stored, size, ventilation pattern and the number of workers in the warehouses during working hours. Electret Ion Chamber Technology (EIC) with the trade name E-PERM TM was employed for the measurement of radon concentration in the warehouses. Average radon concentration in the warehouses range between 33.6 Bq m -3 and 117 Bq m -3with an arithmetic mean of 91.62±5.9 Bq m -3.

  18. High variability of indoor radon concentrations in uraniferous bedrock areas in the Balkan region.

    PubMed

    Zunić, Z S; Ujić, P; Nađđerđ, L; Yarmoshenko, I V; Radanović, S B; Komatina Petrović, S; Celiković, I; Komatina, M; Bossew, P

    2014-12-01

    In this work the strong influence of geological factors on the variability of indoor radon is found in two of three geologically very different regions of South-Eastern Europe. A method to estimate the annual mean concentration when one seasonal measurement is missing is proposed. Large differences of radon concentrations in different rooms of the same house and significant difference in radon concentrations in one season comparing it to the others are noted in certain cases. Geological factors that can lead to such behavior are discussed.

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

    NASA Astrophysics Data System (ADS)

    Kapdan, E.; Altinsoy, N.

    2012-04-01

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

  20. Indoor gamma radiation and radon concentrations in a Norwegian carbonatite area.

    PubMed

    Sundal, A V; Strand, T

    2004-01-01

    Results of indoor gamma radiation and radon measurements in 95 wooden dwellings located in a Norwegian thorium-rich carbonatite area using thermoluminescent dosemeters and CR-39 alpha track detectors, respectively, are reported together with a thorough analysis of the indoor data with regard to geological factors. Slightly enhanced radium levels and thorium concentrations of several thousands Bq kg(-1) in the carbonatites were found to cause elevated indoor radon-222 levels and the highest indoor gamma dose rates ever reported from wooden houses in Norway. An arithmetic mean indoor gamma dose rate of 200 nGy h(-1) and a maximum of 620 nGy h(-1) were obtained for the group of dwellings located directly on the most thorium-rich bedrock. PMID:15312702

  1. Indoor radon concentrations and assessment of doses in four districts of the Punjab Province - Pakistan.

    PubMed

    Ur-Rahman, Saeed; Rafique, Muhammad; Matiullah; Anwar, Javaid

    2009-11-01

    Seasonal indoor radon measurement studies have been carried out in four districts, namely, Jhelum, Chakwal, Rawalpindi and Attock of the Punjab Province. In this regard, CR-39 based detectors were installed in bedrooms, drawing rooms and kitchens of 40 randomly selected houses in each district. After exposing to radon in each season, CR-39 detectors were etched in 6M NaOH at 80 degrees C and counted under an optical microscope. Indoor radon activity concentrations in the houses surveyed ranged from 15 +/- 4 to 176 +/- 7 Bq m(-3) with an overall average value of 55 +/- 31 Bq m(-3). The observed annual average values are greater than the world average of 40 Bq m(-3). Maximum indoor radon concentration levels were observed in winter season whereas minimum levels were observed in summer season. None of the measured radon concentration value exceeded the action level of 200-400 Bq m(-3). The season/annual ratios for different type of dwellings varied from 0.87 +/- 0.93 to 1.14 +/- 1.10. The mean annual estimated effective dose received by the residents of the studied area was found to be 1.39 +/- 0.78 mSv. The annual estimated effective dose is less than the recommended action level (3-10 mSv).

  2. Seasonal variation in indoor radon concentrations in dwellings in six districts of the Punjab province, Pakistan.

    PubMed

    Faheem, Munazza; Mati, N; Matiullah

    2007-12-01

    An indoor radon measurement survey has been carried out in six districts of the Punjab province. These included Gujranwala, Gujrat, Hafizabad, Sialkot, Narowal and Mandibahauddin districts. In each district, 40 representative houses were chosen and indoor radon levels were measured in these dwellings in autumn, winter, spring and summer seasons using CR-39 based NRPB radon dosimeters. After exposure to radon, the CR-39 detectors were etched in 25% NaOH at 80 degrees C and track densities were related to radon concentration levels. From the observed data, average radon concentration levels and a seasonal correction factor were calculated. The average 222Rn concentration level was found to vary from 40 +/- 15 to 160 +/- 32 Bq m(-3) and 38 +/- 17 to 141 +/- 26 Bq m(-3) in the bedrooms and living rooms of the houses surveyed, respectively. The annual mean effective dose received by the occupants has been calculated using ICRP (1993 Ann. ICRP 23) and UNSCEAR (2000 Sources and Effects of Ionizing Radiation (New York: United Nations)); it varied from 1.2 to 1.7 mSv and from 1.8 to 2.4 mSv, respectively.

  3. Variation of indoor radon concentrations in two-storey houses in Nowshera District, Pakistan.

    PubMed

    Khan, F; Wazir, Z; Tufail, M; Nusrat, M

    2015-01-01

    A study was performed for the measurement of indoor radon concentration in two-storey houses in district Nowshera in the Khyber Pakhtunkhwa province of Pakistan. This area was not previously surveyed for such kind of study. The aim was to find some correlation of radon levels in first and second storey houses in the area. The measurements were carried out for 1 y from 1 December 2012 to 30 November 2013 using CR-39 detector. The area was divided into four parts, namely, Jhangera, Nowshera city, Akora Khattak and Pabbi. In the first storey houses, radon concentration ranged from 29 to 103 Bq m(-3) with the mean value of 64 ± 12 Bq m(-3) and that in the second storey houses ranged from 25 to 92 Bq m(-3) with the mean value of 56 ± 11 Bq m(-3). Relatively higher values of indoor radon levels in the first stories than the second stories were observed in all four parts of the study area. The effective doses received by the residents of the area were estimated for each part. The mean annual effective doses received by the inhabitants of the area from indoor radon ranged from 0.68 to 2.88 mSv with the mean value of 1.68 ± 0.32 mSv. The doses received by the people of the area were within the ICRP-65 recommended range (3-10 mSv).

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

    PubMed

    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.

  5. Indoor radon activity concentration measurements in the great historical museums of University of Naples, Italy.

    PubMed

    Quarto, Maria; Pugliese, Mariagabriella; Loffredo, Filomena; La Verde, Giuseppe; Roca, Vincenzo

    2016-01-01

    Indoor radon activity concentrations were measured in seven Museums of University of Naples, very old buildings of great historical value. The measurements were performed using a time-integrated technique based on LR-115 solid-state nuclear track detectors. The annual average concentrations were found to range from 40 up to 1935 Bq m(-3) and in 26 % of measurement sites, the values were higher than 500 Bq m(-3) which is the limit value of Italian legislation for workplace. Moreover, we analysed the seasonal variations of radon concentrations observing the highest average in cold weather than in warm.

  6. Evaluation of indoor aerosol control devices and their effects on radon progeny concentrations. Revision

    SciTech Connect

    Sextro, R.G.; Offermann, F.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.L.; Yater, J.

    1984-11-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. The experiments were conducted in a room-size chamber using cigarette smoke and radon injection from an external source. Of the devices examined the electrostatic precipitators and extended surface filters had significant particle removal rates, while the particle removal rates for several small panel-filters, an ion-generator, and a pair of mixing fans were found to be essentially negligible. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in reducing radon progeny concentrations. At the low particle concentrations, deposition of the unattached radon progeny on room surfaces was found to be a significant removal mechanism. Deposition rates of attached and unattached progeny have been estimated from these data, and were used to calculate the equilibrium factors for total and unattached progeny concentrations as a function of particle concentration. While particle removal reduces total airborne radon progeny concentrations, the relative alpha decay dose to the lungs appears to change very little as the particle concentration decreases due to the greater radiological importance of unattached progeny.

  7. Predicting New Hampshire Indoor Radon Concentrations from geologic information and other covariates

    SciTech Connect

    Apte, M.G.; Price, P.N.; Nero, A.V.; Revzan, K.L.

    1998-05-01

    Generalized geologic province information and data on house construction were used to predict indoor radon concentrations in New Hampshire (NH). A mixed-effects regression model was used to predict the geometric mean (GM) short-term radon concentrations in 259 NH towns. Bayesian methods were used to avoid over-fitting and to minimize the effects of small sample variation within towns. Data from a random survey of short-term radon measurements, individual residence building characteristics, along with geologic unit information, and average surface radium concentration by town, were variables used in the model. Predicted town GM short-term indoor radon concentrations for detached houses with usable basements range from 34 Bq/m{sup 3} (1 pCi/l) to 558 Bq/m{sup 3} (15 pCi/l), with uncertainties of about 30%. A geologic province consisting of glacial deposits and marine sediments, was associated with significantly elevated radon levels, after adjustment for radium concentration, and building type. Validation and interpretation of results are discussed.

  8. Influence of ventilation strategies on indoor radon concentrations based on a semiempirical model for Florida-style houses

    SciTech Connect

    Hintenlang, D.E.; Al-Ahmady, K.K.

    1994-04-01

    Measurements in a full-scale experimental facility are used to benchmark a semiempirical model for predicting indoor radon concentrations for Florida-style houses built using slab-on-grade construction. The model is developed to provide time-averaged indoor radon concentrations from quantitative relationships between the time-dependent radon entry and elimination mechanisms that have been demonstrated to be important for this style of residential construction. The model successfully predicts indoor radon concentrations in the research structure for several pressure and ventilation conditions. Parametric studies using the model illustrate how different ventilation strategies affect indoor radon concentrations. It is demonstrated that increasing house ventilation rates by increasing the effective leakage area of the house shell does not reduce indoor radon concentrations as effectively as increasing house ventilation rates by controlled duct ventilation associated with the heating, ventilating, and air conditioning system. The latter strategy provides the potential to minimize indoor radon concentrations while providing positive control over the quality of infiltration air. 9 refs., 5 figs.

  9. Distribution of indoor radon concentrations and elements of a strategy for control

    SciTech Connect

    Nero, A.V. Jr.

    1986-05-01

    Indoor radon concentrations vary widely in the US housing stock, with normal concentrations estimated to cause a significant risk of lung cancer by comparison with environmental exposures normally considered, and high concentrations causing risks that exceed even those from cigarette smoking. The probability distribution, i.e., the number of houses at various concentrations, can be estimated from an analysis of the US indoor radon data accumulated to date. Such an analysis suggests that in about a million houses, occupants are receiving exposures greater than those experienced by uranium miners. The form of the frequency distribution, including not only the average concentration, but also the number of houses with high levels, has substantial influence on strategies for control of indoor radon. Such strategies require three major elements: formulation of control objectives in terms of guidelines for remedial action and for new houses; selection of means for identifying homes with high concentrations; and a framework for deciding what types of control measures are appropriate to particular circumstances and how rapidly they should be employed.

  10. Hierarchical modeling of indoor radon concentration: how much do geology and building factors matter?

    PubMed

    Borgoni, Riccardo; De Francesco, Davide; De Bartolo, Daniela; Tzavidis, Nikos

    2014-12-01

    Radon is a natural gas known to be the main contributor to natural background radiation exposure and only second to smoking as major leading cause of lung cancer. The main concern is in indoor environments where the gas tends to accumulate and can reach high concentrations. The primary contributor of this gas into the building is from the soil although architectonic characteristics, such as building materials, can largely affect concentration values. Understanding the factors affecting the concentration in dwellings and workplaces is important both in prevention, when the construction of a new building is being planned, and in mitigation when the amount of Radon detected inside a building is too high. In this paper we investigate how several factors, such as geologic typologies of the soil and a range of building characteristics, impact on indoor concentration focusing, in particular, on how concentration changes as a function of the floor level. Adopting a mixed effects model to account for the hierarchical nature of the data, we also quantify the extent to which such measurable factors manage to explain the variability of indoor radon concentration.

  11. Quality control of mitigation methods for unusually high indoor radon concentrations.

    PubMed

    Huber, J; Ennemoser, O; Schneider, P

    2001-08-01

    The present study's objective was to control the quality of different mitigation methods for unusually high indoor radon (222Rn) concentrations of up to 274,000 Bq m(-3) in a village (Umhausen, 2,600 inhabitants) in western Tyrol, Austria. Five years after mitigation, five different remedial actions were examined on their quality by means of measuring indoor radon concentrations with charcoal liquid scintillation radon detectors and with a continuously recording AlphaGuard detector. Mitigation method in house 1--a mechanical intake and outlet ventilation system with heat exchanger in the basement, combined with a soil depressurization system--was characterized by long-term stability. With most favorable air pressure (+100 Pa) in the basement, mean basement radon concentrations in the winter were reduced from 200,000 Bq m(-3) to 3,000 Bq m(-3) by this method 5 y after mitigation. Acting against experts' instructions, the inhabitants had switched off the ventilation system most of the time to minimize power consumption although it had been proven that ventilation reduced mean basement radon concentration by a factor of about 3 in the winter and about 15 in the summer. Mitigation method in house 2-soil depressurization with two fans and loops of drainage tubes to withdraw radon from the region below the floor and outside the basement walls, and from soil below that part of the house with no basement-had been the most successful remedial measure until the winter of 1999 (i.e., 6 y after mitigation), when micro-cracks opened and consequently mean basement radon concentration increased from 250 Bq m(-3) to 1,500 Bq m(-3). Measures to block these microcracks and to minimize soil drying are being developed. Five years after mitigation, the remedial method used in house 3--a multilayer floor construction, where a fan was used to suck radon from a layer between bottom slab and floor-reduced winter mean radon concentration from 25,000 Bq m(-3) to 1,200 Bq m(-3), with the

  12. Measurements of indoor radon concentration levels in dwellings in Bethlehem, Palestine.

    PubMed

    Leghrouz, Amin A; Abu-Samreh, Mohammad M; Shehadeh, Ayah K

    2013-02-01

    Indoor radon level measurements were carried out in 42 dwellings in Bethlehem, Palestine, using CR-39 solid state nuclear track detectors. The measurements were performed during winter and spring seasons of the year 2010, for a period ranging from 97-118 d using a total of 100 detectors. The detectors were installed in living rooms, bedrooms, kitchens, and storage areas of 39 houses, as well as in three schools, selected randomly in the surveyed area. The results of indoor radon levels and the annual effective dose in houses were found to vary from 26 - 611 Bq m(-3) and 0.65 - 14.1 m Sv y(-1), with average values of 117.0 Bq m(-3) and 2.95 m Sv y(-1), respectively. The mean values of radon concentration levels in bedrooms, kitchens, living rooms, basements, and storage areas are, respectively, 106.5, 113.1, 101.5, and 164.2 Bq m(-3). The corresponding mean values of annual effective dose for the bedrooms, kitchens, living rooms, basements, and storage areas are 2.66, 2.83, 2.54, 14.1 m Sv y(-1), respectively. In schools, the radon levels are found to vary from 31 - 400 Bq m(-3) with an average value of 125.1 Bq m(-3). The average annual effective dose in schools is found to be 3.12 mSv y(-1). This value is higher than the assigned international value. In general, the results show that radon concentration levels in 83% of the investigated dwellings are lower than the indoor radon action level of 150 Bq m(-3) for the United States.

  13. Comparative studies of indoor radon concentration levels in Jordan using CR-39 based bag and cup dosimeters.

    PubMed

    Ahmad, N; Matiullah; Khatibeh, A J

    1998-07-01

    Indoor radon concentration levels have been measured in 9 major cities of Jordan using CR(-3)9 detectors placed in punched polyethylene bags to measure both radon and thoron, and in cups to measure radon only. The average value of indoor radon and thoron concentration levels measured with bag dosimeters vary from 32 to 107 Bq m(-3) and the indoor radon concentration levels measured with cup dosimeters vary from 27 to 88 Bq m(-3). The indoor radon concentration levels in Irbid and Zaraka are comparable to the world average of 27 Bq m(-3). In Ajloun, Jerash, Salt, Tafilah and Amman, the indoor radon levels are greater than the world average by a factor of up to 2, and in Madaba and Karak these levels are greater than the world average by a factor of more than 3. The large variation in the measured radon levels may be attributed to the large variation in the 226Ra activity in the soil of the region.

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

    SciTech Connect

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

    1996-06-01

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

  15. Influence of local geology on the concentration of indoor radon in Maryland

    SciTech Connect

    Mose, D.G.; Mushrush, G.W.

    1999-10-01

    Approximately 58,000 indoor radon measurements are available for homes in Maryland. A comparative study between compilations of activated-charcoal and alpha-track measurements of indoor radon in zip-code-size geographic areas indicated that both of these methods are useful and are equally able to estimate regional indoor radon. Indoor radon measurements compiled according to zip code areas can be used to create state-size radon hazard maps. In Maryland the area with the highest indoor radon (mostly composed of zip code areas that average over 8 pCi/L) is the western half of the Piedmont Province and the eastern side of the Coastal Plain Province. The eastern half of the Piedmont and the eastern half of the Valley and Ridge mostly have intermediate and high indoor radon levels (4--8 and >8 pCi/L). The Blue Ridge, western side of the Valley and Ridge, and Plateau Province each has relatively few zip code areas, but the data suggest a range from low to high indoor radon levels. The western side of the Coastal Plain has the lowest indoor radon (most of the zip code areas average less than 4 pCi/L).

  16. Natural radioactivity, radon exhalation rates and indoor radon concentration of some granite samples used as construction material in Turkey.

    PubMed

    Aykamis, Ahmet S; Turhan, Seref; Aysun Ugur, F; Baykan, Umut N; Kiliç, Ahmet M

    2013-11-01

    It is very important to determine the levels of the natural radioactivity in construction materials and radon exhalation rate from these materials for assessing potential exposure risks for the residents. The present study deals with 22 different granite samples employed as decoration stones in constructions in Turkey. The natural radioactivity in granite samples was measured by gamma-ray spectrometry with an HPGe detector. The activity concentrations of (226)Ra, (232)Th and (40)K were found to be in the range of 10-187, 16-354 and 104-1630 Bq kg(-1), respectively. The radon surface exhalation rate and the radon mass exhalation rate estimated from the measured values of (226)Ra content and material properties varied from 1.3 to 24.8 Bq m(-2) h(-1) with a mean of 10.5±1.5 Bq m(-2) h(-1) and 0.03-0.64 Bq kg(-1) h(-1) with a mean of 0.27±0.04 Bq kg(-1) h(-1), respectively. Radon concentrations in the room caused from granite samples estimated using a mass balance equation varied from 23 to 461 Bq m(-3) with a mean of 196±27 Bq m(-3). Also the gamma index (Iγ), external indoor annual effective dose (Eγ) and annual effective dose due to the indoor radon exposure (ERn) were estimated as the average value of 1.1±0.1, 0.16±0.02 mSv and 5.0±0.7 mSv, respectively, for the granite samples. PMID:23633647

  17. Natural radioactivity, radon exhalation rates and indoor radon concentration of some granite samples used as construction material in Turkey.

    PubMed

    Aykamis, Ahmet S; Turhan, Seref; Aysun Ugur, F; Baykan, Umut N; Kiliç, Ahmet M

    2013-11-01

    It is very important to determine the levels of the natural radioactivity in construction materials and radon exhalation rate from these materials for assessing potential exposure risks for the residents. The present study deals with 22 different granite samples employed as decoration stones in constructions in Turkey. The natural radioactivity in granite samples was measured by gamma-ray spectrometry with an HPGe detector. The activity concentrations of (226)Ra, (232)Th and (40)K were found to be in the range of 10-187, 16-354 and 104-1630 Bq kg(-1), respectively. The radon surface exhalation rate and the radon mass exhalation rate estimated from the measured values of (226)Ra content and material properties varied from 1.3 to 24.8 Bq m(-2) h(-1) with a mean of 10.5±1.5 Bq m(-2) h(-1) and 0.03-0.64 Bq kg(-1) h(-1) with a mean of 0.27±0.04 Bq kg(-1) h(-1), respectively. Radon concentrations in the room caused from granite samples estimated using a mass balance equation varied from 23 to 461 Bq m(-3) with a mean of 196±27 Bq m(-3). Also the gamma index (Iγ), external indoor annual effective dose (Eγ) and annual effective dose due to the indoor radon exposure (ERn) were estimated as the average value of 1.1±0.1, 0.16±0.02 mSv and 5.0±0.7 mSv, respectively, for the granite samples.

  18. Characterizing the source of radon indoors

    SciTech Connect

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

    1983-09-01

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

  19. Prediction of indoor radon concentrations in dwellings in the Oslo region - a model based on geographical information systems

    NASA Astrophysics Data System (ADS)

    Kollerud, R.; Blaasaas, K.; Ganerød, G.; Daviknes, H. K.; Aune, E.; Claussen, B.

    2013-06-01

    The purpose of this study was to develop a method to estimate the radon concentration inside each dwelling in the Oslo region, Norway. The model was based on indoor radon measurements from dwellings at predefined distances from the unmeasured dwellings. The results were evaluated by comparing them with actual indoor measurements, airborne gamma ray spectrometry measurements and bedrock geology. It is the first study to evaluate the reliability between estimated indoor radon in each dwelling with airborne measurements (eK, eTh and eU) and underlying geology around the house in a large population. A total of 28 396 indoor radon measurements showed that 42.2% of the dwellings had a radon value higher than the threshold limit of 100 Bq m-3. 18.9% of the dwellings were above the maximum action level of 200 Bq m-3. A positive correlation was found between indoor radon concentration, bedrock geology and airborne gamma measurements (Pearson correlation: eK: 0.42, eTh: 0.67 and eU: 0.65). Highest correlation was found in areas with alum shale (eU: 0.74). Intraclass Correlation Coefficients (ICCs) showed a good agreement between radon estimates from our method and radon estimates from the regression model with ICC values between 0.54 and 0.67.

  20. Effect of soil moisture on seasonal variation in indoor radon concentration: modelling and measurements in 326 Finnish houses.

    PubMed

    Arvela, H; Holmgren, O; Hänninen, P

    2016-02-01

    The effect of soil moisture on seasonal variation in soil air and indoor radon is studied. A brief review of the theory of the effect of soil moisture on soil air radon has been presented. The theoretical estimates, together with soil moisture measurements over a period of 10 y, indicate that variation in soil moisture evidently is an important factor affecting the seasonal variation in soil air radon concentration. Partitioning of radon gas between the water and air fractions of soil pores is the main factor increasing soil air radon concentration. On two example test sites, the relative standard deviation of the calculated monthly average soil air radon concentration was 17 and 26%. Increased soil moisture in autumn and spring, after the snowmelt, increases soil gas radon concentrations by 10-20 %. In February and March, the soil gas radon concentration is in its minimum. Soil temperature is also an important factor. High soil temperature in summer increased the calculated soil gas radon concentration by 14%, compared with winter values. The monthly indoor radon measurements over period of 1 y in 326 Finnish houses are presented and compared with the modelling results. The model takes into account radon entry, climate and air exchange. The measured radon concentrations in autumn and spring were higher than expected and it can be explained by the seasonal variation in the soil moisture. The variation in soil moisture is a potential factor affecting markedly to the high year-to-year variation in the annual or seasonal average radon concentrations, observed in many radon studies.

  1. Indoor radon survey in Visegrad countries.

    PubMed

    Műllerová, Monika; Kozak, Krzysztof; Kovács, Tibor; Smetanová, Iveta; Csordás, Anita; Grzadziel, Dominik; Holý, Karol; Mazur, Jadwiga; Moravcsík, Attila; Neznal, Martin; Neznal, Matej

    2016-04-01

    The indoor radon measurements were carried out in 123 residential buildings and 33 schools in Visegrad countries (Slovakia, Hungary and Poland). In 13.2% of rooms radon concentration exceeded 300Bqm(-3), the reference value recommended in the Council Directive 2013/59/EURATOM. Indoor radon in houses shows the typical radon behavior, with a minimum in the summer and a maximum in the winter season, whereas in 32% of schools the maximum indoor radon was reached in the summer months. PMID:26774389

  2. Predicted indoor radon concentrations from a Monte Carlo simulation of 1,000,000 granite countertop purchases.

    PubMed

    Allen, J G; Zwack, L M; MacIntosh, D L; Minegishi, T; Stewart, J H; McCarthy, J F

    2013-03-01

    Previous research examining radon exposure from granite countertops relied on using a limited number of exposure scenarios. We expanded upon this analysis and determined the probability that installing a granite countertop in a residential home would lead to a meaningful radon exposure by performing a Monte Carlo simulation to obtain a distribution of potential indoor radon concentrations attributable to granite. The Monte Carlo analysis included estimates of the probability that a particular type of granite would be purchased, the radon flux associated with that type, the size of the countertop purchased, the volume of the home where it would be installed and the air exchange rate of that home. One million countertop purchases were simulated and 99.99% of the resulting radon concentrations were lower than the average outdoor radon concentrations in the US (14.8 Bq m(-3); 0.4  pCi l(-1)). The median predicted indoor concentration from granite countertops was 0.06 Bq m(-3) (1.59 × 10(-3) pCi l(-1)), which is over 2000 times lower than the US Environmental Protection Agency's action level for indoor radon (148 Bq m(-3); 4 pCi l(-1)). The results show that there is a low probability of a granite countertop causing elevated levels of radon in a home. PMID:23295242

  3. Predicted indoor radon concentrations from a Monte Carlo simulation of 1,000,000 granite countertop purchases.

    PubMed

    Allen, J G; Zwack, L M; MacIntosh, D L; Minegishi, T; Stewart, J H; McCarthy, J F

    2013-03-01

    Previous research examining radon exposure from granite countertops relied on using a limited number of exposure scenarios. We expanded upon this analysis and determined the probability that installing a granite countertop in a residential home would lead to a meaningful radon exposure by performing a Monte Carlo simulation to obtain a distribution of potential indoor radon concentrations attributable to granite. The Monte Carlo analysis included estimates of the probability that a particular type of granite would be purchased, the radon flux associated with that type, the size of the countertop purchased, the volume of the home where it would be installed and the air exchange rate of that home. One million countertop purchases were simulated and 99.99% of the resulting radon concentrations were lower than the average outdoor radon concentrations in the US (14.8 Bq m(-3); 0.4  pCi l(-1)). The median predicted indoor concentration from granite countertops was 0.06 Bq m(-3) (1.59 × 10(-3) pCi l(-1)), which is over 2000 times lower than the US Environmental Protection Agency's action level for indoor radon (148 Bq m(-3); 4 pCi l(-1)). The results show that there is a low probability of a granite countertop causing elevated levels of radon in a home.

  4. Indoor radon measurements in Turkey dwellings.

    PubMed

    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.

  5. Comparisons between soil radon and indoor radon

    SciTech Connect

    Mose, D.G.; Mushrush, G.W.

    1999-10-01

    Several thousand indoor radon measurements have been obtained for homes in northern Virginia. Compilations of these data according to the geologic units under the homes show that some units have relatively high or relatively low medium indoor radon levels, and that these differences persist through all four seasons. An attempt to determine if soil radon and soil permeability could yield similar results, in terms of relative indoor radon, was not successful. Care should be taken in using such measurements to characterize the potential for radon problems in established communities and in areas of as-yet undeveloped property.

  6. Indoor/outdoor radon decay products associated aerosol particle-size distributions and their relation to total number concentrations.

    PubMed

    Moriizumi, Jun; Yamada, Shinya; Xu, Yang; Matsuki, Satoru; Hirao, Shigekazu; Yamazawa, Hiromi

    2014-07-01

    The activity size distributions of indoor and outdoor radioactive aerosol associated with short-lived radon decay products were observed at Nagoya, Japan, for some periods from 2010 to 2012, following the indoor observation by Mostafa et al. [Mostafa, A. M. A., Tamaki, K., Moriizumi, J., Yamazawa, H. and Iida, T. The weather dependence of particle size distribution of indoor radioactive aerosol associated with radon decay products. Radiat. Prot. Dosim. 146: (1-3), 19-22 (2011)]. The tendency of smaller indoor activity median aerodynamic diameter (AMAD) after rainfalls showed in the previous study was not consistently obtained, while the consistent tendency of less indoor radioactive particles with diameters in the accumulation mode was observed again after rainfalls. The indoor aerosols showed activity size distributions similar to the outdoor ones. Non-radioactive aerosol particle concentrations measured with a laser particle counter suggested a somewhat liner relationship with AMAD.

  7. Indoor and outdoor Radon concentration measurements in Sivas, Turkey, in comparison with geological setting.

    PubMed

    Mihci, Metin; Buyuksarac, Aydin; Aydemir, Attila; Celebi, Nilgun

    2010-11-01

    Indoor and soil gas Radon ((222)Rn) concentration measurements were accomplished in two stages in Sivas, a central eastern city in Turkey. In the first stage, CR-39 passive nuclear track detectors supplied by the Turkish Atomic Energy Authority (TAEA) were placed in the selected houses throughout Sivas centrum in two seasons; summer and winter. Before the setup of detectors, a detailed questionnaire form was distributed to the inhabitants of selected houses to investigate construction parameters and properties of the houses, and living conditions of inhabitants. Detectors were collected back two months later and analysed at TAEA laboratories to obtain indoor (222)Rn gas concentration values. In the second stage, soil gas (222)Rn measurements were performed using an alphameter near the selected houses for the indoor measurements. Although (222)Rn concentrations in Sivas were quite low in relation with the allowable limits, they are higher than the average of Turkey. Indoor and soil gas (222)Rn concentration distribution maps were prepared seperately and these maps were applied onto the surface geological map. In this way, both surveys were correlated with the each other and they were interpreted in comparison with the answers of questionnaire and the geological setting of the Sivas centrum and the vicinity.

  8. Time-Averaged Indoor Radon Concentrations and Infiltration RatesSampled in Four U.S. Cities

    SciTech Connect

    Doyle, S.M.; Nazaroff, W.W.; Nero, A.V.

    1983-09-01

    Indoor radon concentrations, measured in 58 houses over a four to five month period during the winter and spring of 1981-1982, varied from 0.1 to 16 pCi 1{sup -1} (4-590 Bq m{sup -3}). Average infiltration rates were determined for each house over the same period, based on a measurement of the effective leakage area and an infiltration model, and found to range from 0.2 to 2.2 air changes per hour (hr{sup -1}). Indoor radon concentrations correlated poorly with infiltration rates for houses within each city as well as for the entire sample. Differences in radon entry rates among houses thus appear to be more important than differences in infiltration rates in determining whether a house has high indoor radon levels, consistent with previous indications from grab-sample measurements. Radon entry rates and indoor radon concentrations were generally higher in houses in Fargo, ND and Colorado Springs, CO than in houses in Portland, ME and Charleston, NC.

  9. Study of Relation between Indoor Radon in Multi-storey Building and Outdoor Factors

    SciTech Connect

    Muellerova, Monika; Holy, Karol

    2010-01-05

    A continuous radon monitoring in indoor and outdoor air was carried out for the period of one year. The relation between indoor radon and indoor-outdoor temperature difference, as well as between indoor radon and outdoor radon was investigated. The best correlation was obtained between indoor and outdoor radon concentrations.

  10. Study of Relation between Indoor Radon in Multi-storey Building and Outdoor Factors

    NASA Astrophysics Data System (ADS)

    Müllerová, Monika; Holý, Karol

    2010-01-01

    A continuous radon monitoring in indoor and outdoor air was carried out for the period of one year. The relation between indoor radon and indoor-outdoor temperature difference, as well as between indoor radon and outdoor radon was investigated. The best correlation was obtained between indoor and outdoor radon concentrations.

  11. High indoor radon concentrations in an Alpine region of western Tyrol.

    PubMed

    Ennemoser, O; Ambach, W; Auer, T; Brunner, P; Schneider, P; Oberaigner, W; Purtscheller, F; Stingl, V

    1994-08-01

    In a village in western Tyrol, Austria (Umhausen, 2,600 inhabitants), unusually high indoor radon concentrations were measured, and the lung cancer mortality rate was found to be higher than that of the total population of Tyrol (620,000 inhabitants). Annual means of radon concentrations were found to be particularly high in the area between the two rivers Otztaler Ache and Hairlachbach, geologically an alluvial fan of a giant rock slide of granitic gneisses (area A, median of annual means on the ground floors: 1,868 Bq m-3); radon concentrations were comparatively low in the rest of the village (area B, median of annual means on the ground floors: 182 Bq m-3). On the basis of these medians, the annual exposures were calculated according to the ICRP model (area A: 58.8 x 10(5) Bq h m-3; area B: 5.7 x 10(5) Bq h m-3). Data taken from the Cancer Registry of Tyrol were used to determine the age- and sex-standardized lung cancer mortality rate (area A: 6.17; area B: 1.43). PMID:8026968

  12. Seasonal Variation of Indoor Radon Concentration in the Tropics: Comparative studies between Kuala Lumpur, Malaysia and Kerala, India

    NASA Astrophysics Data System (ADS)

    Mahat, R. H.; Jojo, P. J.; Pereira, C. E.; Amin, Y. M.

    2011-03-01

    The radiation dose received by man from indoor radon and its progeny is the largest at more than 50% of total dose received. The seasonal variation of indoor radon concentration in Kerala, India and Kuala Lumpur, Malaysia were studied. The Southwest coast of the Kerala state in India is known to have very high levels of natural background radiation owing to the rare earths rich monazite sand available in large amount. Kuala Lumpur, Malaysia used to be a famous tin mining area where it was done using open cast system. One-year measurements of radon concentration in houses were done for these two regions. It was found that there is considerable seasonal variation in the levels of radon in Kerala but the variation in Kuala Lumpur is only less than 10%.

  13. Seasonal Variation of Indoor Radon Concentration in the Tropics: Comparative studies between Kuala Lumpur, Malaysia and Kerala, India

    SciTech Connect

    Mahat, R. H.; Amin, Y. M.; Jojo, P. J.; Pereira, C. E.

    2011-03-30

    The radiation dose received by man from indoor radon and its progeny is the largest at more than 50% of total dose received. The seasonal variation of indoor radon concentration in Kerala, India and Kuala Lumpur, Malaysia were studied. The Southwest coast of the Kerala state in India is known to have very high levels of natural background radiation owing to the rare earths rich monazite sand available in large amount. Kuala Lumpur, Malaysia used to be a famous tin mining area where it was done using open cast system. One-year measurements of radon concentration in houses were done for these two regions. It was found that there is considerable seasonal variation in the levels of radon in Kerala but the variation in Kuala Lumpur is only less than 10%.

  14. Multi-scale variability and long-range memory in indoor Radon concentrations from Coimbra, Portugal

    NASA Astrophysics Data System (ADS)

    Donner, Reik V.; Potirakis, Stelios; Barbosa, Susana

    2014-05-01

    The presence or absence of long-range correlations in the variations of indoor Radon concentrations has recently attracted considerable interest. As a radioactive gas naturally emitted from the ground in certain geological settings, understanding environmental factors controlling Radon concentrations and their dynamics is important for estimating its effect on human health and the efficiency of possible measures for reducing the corresponding exposition. In this work, we re-analyze two high-resolution records of indoor Radon concentrations from Coimbra, Portugal, each of which spans several months of continuous measurements. In order to evaluate the presence of long-range correlations and fractal scaling, we utilize a multiplicity of complementary methods, including power spectral analysis, ARFIMA modeling, classical and multi-fractal detrended fluctuation analysis, and two different estimators of the signals' fractal dimensions. Power spectra and fluctuation functions reveal some complex behavior with qualitatively different properties on different time-scales: white noise in the high-frequency part, indications of some long-range correlated process dominating time scales of several hours to days, and pronounced low-frequency variability associated with tidal and/or meteorological forcing. In order to further decompose these different scales of variability, we apply two different approaches. On the one hand, applying multi-resolution analysis based on the discrete wavelet transform allows separately studying contributions on different time scales and characterize their specific correlation and scaling properties. On the other hand, singular system analysis (SSA) provides a reconstruction of the essential modes of variability. Specifically, by considering only the first leading SSA modes, we achieve an efficient de-noising of our environmental signals, highlighting the low-frequency variations together with some distinct scaling on sub-daily time-scales resembling

  15. Indoor radon in New York State schools

    SciTech Connect

    Condon, W.; Ort, S.V.; Rimawi, K.; Papura, T.

    1995-12-31

    New York State participated in a project to study radon in schools funded in part through a grant from the Environmental Protection Agency (EPA). Candidate schools were selected from areas in which existing information suggested there may be a high risk for indoor radon. These schools were invited to participate in an indoor radon survey that included short-term, confirmatory, long-term and post-mitigation measurements. Additionally, the soils under and around eighteen of the schools were measured for indoor radon potential through soil gas measurements and examined for correlation with indoor radon concentrations. Fifty-nine schools were surveyed during the project. Thirty-four of the schools were found to have one or more rooms with long-term radon levels exceeding EPA guidelines. Five of the thirty-four schools have successfully completed mitigation measures.

  16. The results of integration measurements of indoor radon activity concentration in houses in Ružomberok town (Northern Slovakia)

    NASA Astrophysics Data System (ADS)

    Smetanová, Iveta; Műllerová, Monika; Holý, Karol; Moravcsík, Attila; Kovács, Tibor; Csordás, Anita; Neznal, Martin; Neznal, Matej; Kozak, Krzysztof; Mazur, Jadwiga; Grzadziel, Dominik

    2015-03-01

    Integration measurements of indoor radon in houses were performed within the framework of the project "Harmonization of determining the radiation dose of the population originating from radon in V4 countries". In Slovakia, the survey was performed in three localities: Záhorská Bystrica, Mochovce and Ružomberok. Monitoring started in March 2012 and lasted for one year. In Ružomberok ten houses were selected for monitoring purposes. The houses built before 1990 were predominantly chosen for the investigation. In selected houses in Ružomberok, radon activity concentration rarely exceeded 400 Bq/m3 in a three month period, in this case the inhabitants were advised how to lower radon exposure. No house was found with an annual radon activity concentration of more than 400 Bq/m3.

  17. Exposure to unusually high indoor radon levels

    SciTech Connect

    Rasheed, F.N. )

    1993-03-27

    Unusually high indoor radon concentrations were reported in a small village in western Tyrol, Austria. The authors have measured the seasonal course of indoor radon concentrations in 390 houses of this village. 71% of houses in winter and 33% in summer, showed radon values on the ground floor above the Austrian action level of 400 Bq/cm[sup 3]. This proportion results in an unusually high indoor radon exposure of the population. The radon source was an 8,700-year-old rock slide of granite gneiss, the largest of the alpine crystalline rocks. It has a strong emanating power because its rocks are heavily fractured and show a slightly increased uranium content. Previous reports show increased lung cancer mortality, myeloid leukemia, kidney cancer, melanoma, and prostate cancer resulting from indoor radon exposure. However, many studies fail to provide accurate information on indoor radon concentrations, classifying them merely as low, intermediate, and high, or they record only minor increases in indoor radon concentrations. Mortality data for 1970-91 were used to calculate age and sex standardized mortality rates (SMR) for 51 sites of carcinoma. The total population of Tyrol were controls. A significantly higher risk was recorded for lung cancer. The high SMR for lung cancer in female subjects is especially striking. Because the numbers were low for the other cancer sites, these were combined in one group to calculate the SMR. No significant increase in SMR was found for this group.

  18. Survey of Indoor Radon Concentrations in California Elementary Schools. Final Report.

    ERIC Educational Resources Information Center

    Zhou, Joey Y.; Liu, Kai-Shen; Waldman, Jed

    This paper reports on the concentrations of radon found within a sample of 378 elementary schools in California. Long-term alpha-track radon detectors were placed in 6,485 classrooms within participating schools to detect radon levels for between 220 to 366 days. Only classrooms were tested. Results show that about 5.6 percent of the schools…

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

    PubMed

    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. PMID:26874612

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

    PubMed

    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.

  1. Indoor concentration of radon, thoron and their progeny around granite regions in the state of Karnataka, India.

    PubMed

    Sannappa, J; Ningappa, C

    2014-03-01

    An extensive studies on the indoor activity concentrations of thoron, radon and their progeny in the granite region in the state of Karnataka, India, has been carried out since, 2007 in the scope of a lung cancer epidemiological study using solid-state nuclear track detector-based double-chamber dosemeters (LR-115, type II plastic track detector). Seventy-four dwellings of different types were selected for the measurement. The dosemeters containing SSNTD detectors were fixed 2 m above the floor. After an exposure time of 3 months (90 d), films were etched to reveal tracks. From the track density, the concentrations of radon and thoron were evaluated. The value of the indoor concentration of thoron and radon in the study area varies from 16 to 170 Bq m(-3) and 18 to 300 Bq m(-3) with medians of 66 and 82.3 Bq m(-3), respectively, and that of their progeny varies from 1.8 to 24 mWL with a median of 3.6 mWL and 1.6 to 19.6 mWL, respectively. The concentrations of indoor thoron, radon and their progeny and their equivalent effective doses are discussed. PMID:24106330

  2. Indoor concentration of radon, thoron and their progeny around granite regions in the state of Karnataka, India.

    PubMed

    Sannappa, J; Ningappa, C

    2014-03-01

    An extensive studies on the indoor activity concentrations of thoron, radon and their progeny in the granite region in the state of Karnataka, India, has been carried out since, 2007 in the scope of a lung cancer epidemiological study using solid-state nuclear track detector-based double-chamber dosemeters (LR-115, type II plastic track detector). Seventy-four dwellings of different types were selected for the measurement. The dosemeters containing SSNTD detectors were fixed 2 m above the floor. After an exposure time of 3 months (90 d), films were etched to reveal tracks. From the track density, the concentrations of radon and thoron were evaluated. The value of the indoor concentration of thoron and radon in the study area varies from 16 to 170 Bq m(-3) and 18 to 300 Bq m(-3) with medians of 66 and 82.3 Bq m(-3), respectively, and that of their progeny varies from 1.8 to 24 mWL with a median of 3.6 mWL and 1.6 to 19.6 mWL, respectively. The concentrations of indoor thoron, radon and their progeny and their equivalent effective doses are discussed.

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

    NASA Astrophysics Data System (ADS)

    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).

  4. Indoor radon in the region of Brussels

    SciTech Connect

    Tondeur, F.; Gerardy, I.; Christiaens, D.; Hallez, S.; Flemal, J.M.

    1999-12-01

    The indoor radon ({sup 222}Rn) concentration has been measured by charcoal detectors in 278 buildings in the region of Brussels, Belgium. The correlation with the nature of the subsoil can be studied in detail thanks to the available geotechnical map. With a geometrical mean indoor radon concentration of 19 Bq m{sup {minus}3}, Brussels can be considered as generally unaffected by the radon problem. No value higher than 400 Bq m{sup {minus}3} (the EU reference level for existing houses) was measured in an occupied room. However, two factors that may enhance the risk are identified: the absence of a basement or a ventilated crawl space, and the presence of loess, under the house. About one third of the houses without basements or ventilated crawl spaces built on loess show an indoor radon concentration above 200 Bq m{sup {minus}3} (the EU reference level for new houses).

  5. A critical analysis of climatic influences on indoor radon concentrations: Implications for seasonal correction.

    PubMed

    Groves-Kirkby, Christopher J; Crockett, Robin G M; Denman, Antony R; Phillips, Paul S

    2015-10-01

    Although statistically-derived national Seasonal Correction Factors (SCFs) are conventionally used to convert sub-year radon concentration measurements to an annual mean, it has recently been suggested that external temperature could be used to derive local SCFs for short-term domestic measurements. To validate this approach, hitherto unanalysed radon and temperature data from an environmentally-stable location were analysed. Radon concentration and internal temperature were measured over periods totalling 1025 days during an overall period of 1762 days, the greatest continuous sampling period being 334 days, with corresponding meteorological data collected at a weather station 10 km distant. Mean daily, monthly and annual radon concentrations and internal temperatures were calculated. SCFs derived using monthly mean radon concentration, external temperature and internal-external temperature-difference were cross-correlated with each other and with published UK domestic SCF sets. Relatively good correlation exists between SCFs derived from radon concentration and internal-external temperature difference but correlation with external temperature, was markedly poorer. SCFs derived from external temperature correlate very well with published SCF tabulations, confirming that the complexity of deriving SCFs from temperature data may be outweighed by the convenience of using either of the existing domestic SCF tabulations. Mean monthly radon data fitted to a 12-month sinusoid showed reasonable correlation with many of the annual climatic parameter profiles, exceptions being atmospheric pressure, rainfall and internal temperature. Introducing an additional 6-month sinusoid enhanced correlation with these three parameters, the other correlations remaining essentially unchanged. Radon latency of the order of months in moisture-related parameters suggests that the principal driver for radon is total atmospheric moisture content rather than relative humidity. PMID:26093853

  6. A critical analysis of climatic influences on indoor radon concentrations: Implications for seasonal correction.

    PubMed

    Groves-Kirkby, Christopher J; Crockett, Robin G M; Denman, Antony R; Phillips, Paul S

    2015-10-01

    Although statistically-derived national Seasonal Correction Factors (SCFs) are conventionally used to convert sub-year radon concentration measurements to an annual mean, it has recently been suggested that external temperature could be used to derive local SCFs for short-term domestic measurements. To validate this approach, hitherto unanalysed radon and temperature data from an environmentally-stable location were analysed. Radon concentration and internal temperature were measured over periods totalling 1025 days during an overall period of 1762 days, the greatest continuous sampling period being 334 days, with corresponding meteorological data collected at a weather station 10 km distant. Mean daily, monthly and annual radon concentrations and internal temperatures were calculated. SCFs derived using monthly mean radon concentration, external temperature and internal-external temperature-difference were cross-correlated with each other and with published UK domestic SCF sets. Relatively good correlation exists between SCFs derived from radon concentration and internal-external temperature difference but correlation with external temperature, was markedly poorer. SCFs derived from external temperature correlate very well with published SCF tabulations, confirming that the complexity of deriving SCFs from temperature data may be outweighed by the convenience of using either of the existing domestic SCF tabulations. Mean monthly radon data fitted to a 12-month sinusoid showed reasonable correlation with many of the annual climatic parameter profiles, exceptions being atmospheric pressure, rainfall and internal temperature. Introducing an additional 6-month sinusoid enhanced correlation with these three parameters, the other correlations remaining essentially unchanged. Radon latency of the order of months in moisture-related parameters suggests that the principal driver for radon is total atmospheric moisture content rather than relative humidity.

  7. Potential health effects of indoor radon exposure.

    PubMed Central

    Radford, E P

    1985-01-01

    Radon-222 is a ubiquitous noble gas arising from decay of radium-226 normally present in the earth's crust. Alpha radiation from inhaled short-lived daughters of radon readily irradiates human bronchial epithelium, and there is now good evidence of excess risk of lung cancer in underground miners exposed to higher concentrations. In homes, radon levels are highly variable, showing approximately log-normal distributions and often a small fraction of homes with high concentrations of radon and radon daughters. Factors affecting indoor concentrations include type of bedrock under dwellings, house foundation characteristics, radon dissolved in artesian water, and ventilation and degree of air movement in living spaces. Despite much recent work, exposures to radon daughters by the general public are not well defined. From application of risk assessments in miners to home conditions, it appears that about 25% or more of lung cancers among nonsmokers over the age of 60, and about 5% in smokers, may be attributable to exposure to radon daughters at home. It may be necessary to take remedial action to reduce this hazard in those dwellings with elevated levels of radon, and new construction should take account of this problem. PMID:4085431

  8. Correlation of soil radon and permeability with indoor radon potential in Ottawa.

    PubMed

    Chen, Jing; Falcomer, Renato; Bergman, Lauren; Wierdsma, Jessica; Ly, Jim

    2009-08-01

    Soil gas radon and soil gas permeability measurements were conducted at 32 sites across the five most populated communities in the city of Ottawa where indoor radon measurements were available for 167 houses. A soil radon index (SRI) determined from the soil radon concentration and the soil gas permeability was used to characterise radon availability from soil to air. This study demonstrated that the average SRI in a community area correlates with the indoor radon potential (the percentage of homes above 200 Bq m(-3)) in that community. Soil gas radon concentrations together with soil gas permeability measurements can be a useful tool for the prediction of the indoor radon potential in the development of a Canadian radon risk map.

  9. Environmental and indoor study of Radon concentration in San Joaquin area, Querétaro, México

    NASA Astrophysics Data System (ADS)

    Kotsarenko, A.; Hernandez Silva, G.; Hinojo Alonso, N. A.; Yutsis, V.; Grimalsky, V.; Koshevaya, S.; Martínez Reyes, J.

    2012-04-01

    Highly contaminated zone with a maximum over 57,000 Bq/m3 was discovered in low-populated area "Agua de Venados" during the 2009-2011 soil Radon survey in San Joaquin, Querétaro state, Mexico. Indoor Radon monitoring accomplished in 2 different époques in a nearby 4 dwellings have shown increased Radon contamination in 1 of the 4 building (up to 300 Bq/m3) during a raining season and a highly elevated indoor level (over 400 Bq/m3) already in 3 buildings during a dry season. Averaged diurnal indoor Radon variations are in a correlation with atmosphere pressure and air humidity and are independent on air temperature. The daily interval 5-10 a.m. was estimated as a maximum risky period in terms of Radon contamination hazard for inhabitants in mentioned zone.

  10. Indoor radon risk potential of Hawaii

    USGS Publications Warehouse

    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??.

  11. Radon daughter carousel: An automated instrument for measuring indoor concentrations of 218Po, 214Pb, and 214Bi

    NASA Astrophysics Data System (ADS)

    Nazaroff, William W.

    1983-09-01

    A microprocessor-controlled instrument for measuring the concentrations of radon progeny in indoor air is described. The measurement technique is based on alpha spectroscopy and uses two counting intervals following a sampling period during which radon progeny are collected on a filter. The counting intervals are selected to provide optimal precision for measuring 222Rn progeny for fixed total measurement times ranging from 30 to 60 min: concentrations as low as 0.5 pCi/1 can be measured with less than 20% uncertainty in 45 min. The instrument can also be used to estimate the potential alpha energy concentration of 220Rn decay products. The device operates under the control of a computer or a data terminal and functions for week-long periods between filter changes. The user can specify the sampling- and counting-interval timing over a wide range and select from among several operating modes. A number of performance tests are also described indicating that for typical indoor concentrations the measurement uncertainty is dominated by counting statistics.

  12. Radon ((222)Rn) concentration in indoor air near the coal mining area of Nui Beo, North of Vietnam.

    PubMed

    Nhan, Dang Duc; Fernando, Carvalho P; Thu Ha, Nguyen Thi; Long, Nguyen Quang; Thuan, Dao Dinh; Fonseca, Heloisa

    2012-08-01

    Concentrations of radioactive radon gas ((222)Rn) were measured using passive monitors based on LR115 solid state track detectors during June-July 2010 in indoor air of dwellings in the Nui Beo coal mining area, mostly in Cam Pha and Ha Long coastal towns, Quang Ninh province, in the North of Vietnam. Global results of (222)Rn concentrations indoors varied from ≤6 to 145 Bq m(-3) averaging 46 ± 26 Bq m(-3) (n = 37), with a median value of 47 Bq m(-3). This was similar to outdoor (222)Rn concentrations in the region, averaging 43 ± 19 Bq m(-3) (n = 10), with a median value of 44 Bq m(-3). Indoor (222)Rn concentrations in the coastal town dwellings only were in average lower although not significantly different from indoor (222)Rn concentrations measured at the coal storage field near the harbor, 67 ± 4 Bq m(-3) (n = 3). Furthermore, there was no significant difference in the average (222)Rn concentration in indoor air measured in the coastal towns region and those at the touristic Tuan Chau Island located about 45 km south of the coal mine, in the Ha Long Bay. The indoor (222)Rn concentration in a floating house at the Bai Tu Long Bay, and assumed as the best estimate of the baseline (222)Rn in surface air, was 27 ± 3 Bq m(-3) (n = 3). Indoor average concentration of (222)Rn in dwellings at the Ha Noi city, inland and outside the coal mining area, was determined at 30 Bq m(-3). These results suggest that (222)Rn exhalation from the ground at the Nui Beo coal mining area may have contributed to generally increase (222)Rn concentration in the surface air of that region up to 1.7 times above the baseline value measured at the Bai Tu Long Bay and Ha Noi. The average indoor concentration of (222)Rn in Cam Pha-Ha Long area is about one-third of the value of the so-called Action Level set up by the US EPA of 148 Bq m(-3). Results suggest that there is no significant public health risk from (222)Rn exposure in the study region.

  13. Indoor radon and lung cancer. Estimating the risks

    SciTech Connect

    Samet, J.M. )

    1992-01-01

    Radon is ubiquitous in indoor environments. Epidemiologic studies of underground miners with exposure to radon and experimental evidence have established that radon causes lung cancer. The finding that this naturally occurring carcinogen is present in the air of homes and other buildings has raised concern about the lung cancer risk to the general population from radon. I review current approaches for assessing the risk of indoor radon, emphasizing the extrapolation of the risks for miners to the general population. Although uncertainties are inherent in this risk assessment, the present evidence warrants identifying homes that have unacceptably high concentrations.23 references.

  14. Indoor radon and lung cancer. Estimating the risks.

    PubMed Central

    Samet, J. M.

    1992-01-01

    Radon is ubiquitous in indoor environments. Epidemiologic studies of underground miners with exposure to radon and experimental evidence have established that radon causes lung cancer. The finding that this naturally occurring carcinogen is present in the air of homes and other buildings has raised concern about the lung cancer risk to the general population from radon. I review current approaches for assessing the risk of indoor radon, emphasizing the extrapolation of the risks for miners to the general population. Although uncertainties are inherent in this risk assessment, the present evidence warrants identifying homes that have unacceptably high concentrations. PMID:1734594

  15. External gamma-ray dose rate and radon concentration in indoor environments covered with Brazilian granites.

    PubMed

    Anjos, R M; Juri Ayub, J; Cid, A S; Cardoso, R; Lacerda, T

    2011-11-01

    Health hazard from natural radioactivity in Brazilian granites, covering the walls and floor in a typical dwelling room, was assessed by indirect methods to predict external gamma-ray dose rates and radon concentrations. The gamma-ray dose rate was estimated by a Monte Carlo simulation method and validated by in-situ measurements with a NaI spectrometer. Activity concentrations of (232)Th, (226)Ra, and (40)K in an extensive selection of Brazilian commercial granite samples measured by using gamma-ray spectrometry were found to be 4.5-450 Bq kg(-1), 4.9-160 Bq kg(-1) and 190-2029 Bq kg(-1), respectively. The maximum external gamma-ray dose rate from floor and walls covered with the Brazilian granites in the typical dwelling room (5.0 m × 4.0 m area, 2.8 m height) was found to be 120 nGy h(-1), which is comparable with the average worldwide exposure to external terrestrial radiation of 80 nGy h(-1) due to natural sources, proposed by United Nations Scientific Committee on the Effects of Atomic Radiation. Radon concentrations in the room were also estimated by a simple mass balance equation and exhalation rates calculated from the measured values of (226)Ra concentrations and the material properties. The results showed that the radon concentration in the room ventilated adequately (0.5 h(-1)) will be lower than 100 Bq m(-3), value recommended as a reference level by the World Health Organization.

  16. External gamma-ray dose rate and radon concentration in indoor environments covered with Brazilian granites.

    PubMed

    Anjos, R M; Juri Ayub, J; Cid, A S; Cardoso, R; Lacerda, T

    2011-11-01

    Health hazard from natural radioactivity in Brazilian granites, covering the walls and floor in a typical dwelling room, was assessed by indirect methods to predict external gamma-ray dose rates and radon concentrations. The gamma-ray dose rate was estimated by a Monte Carlo simulation method and validated by in-situ measurements with a NaI spectrometer. Activity concentrations of (232)Th, (226)Ra, and (40)K in an extensive selection of Brazilian commercial granite samples measured by using gamma-ray spectrometry were found to be 4.5-450 Bq kg(-1), 4.9-160 Bq kg(-1) and 190-2029 Bq kg(-1), respectively. The maximum external gamma-ray dose rate from floor and walls covered with the Brazilian granites in the typical dwelling room (5.0 m × 4.0 m area, 2.8 m height) was found to be 120 nGy h(-1), which is comparable with the average worldwide exposure to external terrestrial radiation of 80 nGy h(-1) due to natural sources, proposed by United Nations Scientific Committee on the Effects of Atomic Radiation. Radon concentrations in the room were also estimated by a simple mass balance equation and exhalation rates calculated from the measured values of (226)Ra concentrations and the material properties. The results showed that the radon concentration in the room ventilated adequately (0.5 h(-1)) will be lower than 100 Bq m(-3), value recommended as a reference level by the World Health Organization. PMID:21729819

  17. Indoor Radon Measurement In The City Of Edirne, Turkey

    NASA Astrophysics Data System (ADS)

    Bozkurt, A.; Kam, E.

    2007-04-01

    This study assesses the indoor radon concentrations for the city of Edirne situated in the European part of Turkey (Eastern Thrace). A total of 88 CR-39 nuclear track detectors were kept in basements of the selected apartment buildings and houses for passively determining the indoor radon levels of the dwellings for a period of three months. The detectors were then collected and a chemical process of etching was applied to the films. At this stage, the tracks left by alpha particles on the films exposed to radon gas were visible and were counted with a microscope (500×magnification) to estimate the corresponding indoor radon concentrations. The average indoor radon concentration was found to be 49.2 Bq/m3 equivalent to an annual effective dose of 1.24 mSv. The measurement results obtained in this study show no significant departure from the other parts of the country.

  18. Indoor Radon Measurement In The City Of Edirne, Turkey

    SciTech Connect

    Bozkurt, A.; Kam, E.

    2007-04-23

    This study assesses the indoor radon concentrations for the city of Edirne situated in the European part of Turkey (Eastern Thrace). A total of 88 CR-39 nuclear track detectors were kept in basements of the selected apartment buildings and houses for passively determining the indoor radon levels of the dwellings for a period of three months. The detectors were then collected and a chemical process of etching was applied to the films. At this stage, the tracks left by alpha particles on the films exposed to radon gas were visible and were counted with a microscope (500xmagnification) to estimate the corresponding indoor radon concentrations. The average indoor radon concentration was found to be 49.2 Bq/m3 equivalent to an annual effective dose of 1.24 mSv. The measurement results obtained in this study show no significant departure from the other parts of the country.

  19. Study of indoor radon distribution using measurements and CFD modeling.

    PubMed

    Chauhan, Neetika; Chauhan, R P; Joshi, M; Agarwal, T K; Aggarwal, Praveen; Sahoo, B K

    2014-10-01

    Measurement and/or prediction of indoor radon ((222)Rn) concentration are important due to the impact of radon on indoor air quality and consequent inhalation hazard. In recent times, computational fluid dynamics (CFD) based modeling has become the cost effective replacement of experimental methods for the prediction and visualization of indoor pollutant distribution. The aim of this study is to implement CFD based modeling for studying indoor radon gas distribution. This study focuses on comparison of experimentally measured and CFD modeling predicted spatial distribution of radon concentration for a model test room. The key inputs for simulation viz. radon exhalation rate and ventilation rate were measured as a part of this study. Validation experiments were performed by measuring radon concentration at different locations of test room using active (continuous radon monitor) and passive (pin-hole dosimeters) techniques. Modeling predictions have been found to be reasonably matching with the measurement results. The validated model can be used to understand and study factors affecting indoor radon distribution for more realistic indoor environment.

  20. Measurements of indoor gamma radiation and radon concentrations in dwellings of Riyadh city, Saudi Arabia.

    PubMed

    Al-Saleh, Ferdoas S

    2007-07-01

    Indoor gamma radiation measurement at dwellings of Riyadh city in Saudi Arabia using TLD has been performed. Measurements were carried out from October 2004 to June 2005. The city was divided into five sectors, for four categories of bed rooms, living rooms, bathrooms and kitchens. The indoor gamma annual absorbed dose of Riyadh city is in the range from 303+/-57 to 700+/-38microGyy(-1) with an average value of 455.1+/-45microGyy(-1). The calculated corresponding annual effective dose to the adult population of the locations will vary from 212+/-40 to 490+/-27microSvy(-1) with an average value of 318.57+/-31microSvy(-1).(222)Rn concentration was measured at dwellings of Riyadh city in Saudi Arabia to estimate effective annual dose to the public from (222)Rn and its progeny. The (222)Rn concentrations were measured using CR-39 detector. The range of annual mean (222)Rn concentrations for all sites was 2-69Bqm(-3) with an average of 18.4Bqm(-3). The effective annual dose was estimated to be 0.46mSvy(-1).

  1. Geogenic and anthropogenic impacts on indoor radon in the Techa River region.

    PubMed

    Yarmoshenko, I; Malinovsky, G; Vasilyev, A; Onischenko, A; Seleznev, A

    2016-11-15

    Indoor radon concentration was studied in the 14 settlements located near the Techa River, which was contaminated by radioactive wastes in 1950-s. Results of the radon survey were used for analysis of the relationship between the indoor radon and main geologic factors (Pre-Jurassic formations, Quaternary sediments and faults), local geogenic radon potential and anthropogenic factors. Main influencing factors explain 58% of the standard deviation of indoor radon concentration. Association of the air exchange influence over radon concentration with underlying geological media was related to different contributions of geogenic advective and diffusive radon entries. The properties of geological formation to transfer radon gas in interaction with the house can be considered within the radon geogenic potential concept. The study of the radon exposure of the Techa River population can be used to estimate the contribution of natural radon to the overall radiation exposure of the local population during the period of radioactive waste discharges. PMID:27474991

  2. Geogenic and anthropogenic impacts on indoor radon in the Techa River region.

    PubMed

    Yarmoshenko, I; Malinovsky, G; Vasilyev, A; Onischenko, A; Seleznev, A

    2016-11-15

    Indoor radon concentration was studied in the 14 settlements located near the Techa River, which was contaminated by radioactive wastes in 1950-s. Results of the radon survey were used for analysis of the relationship between the indoor radon and main geologic factors (Pre-Jurassic formations, Quaternary sediments and faults), local geogenic radon potential and anthropogenic factors. Main influencing factors explain 58% of the standard deviation of indoor radon concentration. Association of the air exchange influence over radon concentration with underlying geological media was related to different contributions of geogenic advective and diffusive radon entries. The properties of geological formation to transfer radon gas in interaction with the house can be considered within the radon geogenic potential concept. The study of the radon exposure of the Techa River population can be used to estimate the contribution of natural radon to the overall radiation exposure of the local population during the period of radioactive waste discharges.

  3. A Geostatistical Approach to Assess the Spatial Association between Indoor Radon Concentration, Geological Features and Building Characteristics: The Case of Lombardy, Northern Italy

    PubMed Central

    Borgoni, Riccardo; Tritto, Valeria; Bigliotto, Carlo; de Bartolo, Daniela

    2011-01-01

    Radon is a natural gas known to be the main contributor to natural background radiation exposure and second to smoking, a major leading cause of lung cancer. The main source of radon is the soil, but the gas can enter buildings in many different ways and reach high indoor concentrations. Monitoring surveys have been promoted in many countries in order to assess the exposure of people to radon. In this paper, two complementary aspects are investigated. Firstly, we mapped indoor radon concentration in a large and inhomogeneous region using a geostatistical approach which borrows strength from the geologic nature of the soil. Secondly, knowing that geologic and anthropogenic factors, such as building characteristics, can foster the gas to flow into a building or protect against this, we evaluated these effects through a multiple regression model which takes into account the spatial correlation of the data. This allows us to rank different building typologies, identified by architectonic and geological characteristics, according to their proneness to radon. Our results suggest the opportunity to differentiate construction requirements in a large and inhomogeneous area, as the one considered in this paper, according to different places and provide a method to identify those dwellings which should be monitored more carefully. PMID:21655128

  4. Indoor radon mapping and its relation to geology in Hungary

    NASA Astrophysics Data System (ADS)

    Minda, Mihály; Tóth, György; Horváth, István; Barnet, Ivan; Hámori, Krisztián; Tóth, Eszter

    2009-04-01

    Indoor radon mapping may show stronger dependence on geological formations if the measured homes are one-storied houses with no basement. In Hungary, 17,244 homes were investigated on the yearly average of indoor radon concentrations; among these homes, there were 6,154, one-storied, no-basement houses. In Hungary, 21 geological units were created relevant for indoor radon index characterized by lithology, the position of the ground water table, and the gas permeability. Maps were drawn of different topography (counties, grid, geological units) and different values (maximum, mean, indoor radon indexes). A kind of standardization of houses was that only the one-storied, no-basement ones were chosen, but from geological point of view some more information was gained when the wall materials (bricks or adobe) were also taken into account. (“Adobe” is made of clay and straw in Hungary, and not burned as brick, just dried on sunshine). Enhanced indoor radon values can be observed on the bedrock of Cenozoic volcanic rocks and their eroded materials deposited on the local alluvial valleys. Another group with relatively increased indoor radon values can be connected to granite bodies. The grid method is useful for covering large state or even continental areas. For practical public use and detailed radon risk mapping geological or administrative unit-systems could yield more reasonable and useful results.

  5. DEVELOPMENT OF ALTERNATE PERFORMANCE STANDARD FOR RADON RESISTANT CONSTRUCTION BASED ON SHORT-TERM/LONG- TERM INDOOR RADON CONCENTRATIONS - VOLUME 1: TECHNICAL REPORT

    EPA Science Inventory

    The report gives results of a study of short- and long-term variations in radon concentration in about 80 houses in Florida. The study involves comparative sampling using the most common radon measurement technologies during the past year. he study, providing the most detailed da...

  6. DEVELOPMENT OF ALTERNATE PERFORMANCE STANDARD FOR RADON RESISTANT CONSTRUCTION BASED ON SHORT-TERM/LONG- TERM INDOOR RADON CONCENTRATIONS - VOLUME 2: APPENDICES

    EPA Science Inventory

    The report gives results of a study of short- and long-term variations in radon concentration in about 80 houses in Florida. The study involves comparative sampling using the most common radon measurement technologies during the past year. he study, providing the most detailed da...

  7. High indoor radon variations and the thermal behavior of eskers.

    PubMed

    Arvela, H; Voutilainen, A; Honkamaa, T; Rosenberg, A

    1994-09-01

    Measurements of indoor radon concentrations in houses built on the Pispala esker in the city of Tampere were taken. The objective was to find connections between indoor radon concentrations, esker topography, and meteorological factors. The results show that not only the permeable soil but also subterranean air-flows in the esker strongly affect the indoor radon concentrations. The difference in temperature between the soil air inside the esker and the outdoor air compels the subterranean air to stream between the upper and lower esker areas. In winter, the radon concentrations are amplified in the upper esker areas where air flows out from the esker. In summer, concentrations are amplified in certain slope zones. In addition, wind direction affects the soil air and indoor radon concentrations when hitting the slopes at right angles. Winter-summer concentration ratios are typically in the range of 3-20 in areas with amplified winter concentration, and 0.1-0.5 in areas with amplified summer concentrations. A combination of winter and summer measurements provides the best basis for making mitigation decisions. On eskers special attention must be paid to building technology because of radon.

  8. High indoor radon variations and the thermal behavior of eskers

    SciTech Connect

    Arvela, H.; Voutilainen, A.; Honkamaa, T.; Rosenberg, A.

    1994-09-01

    Measurements of indoor radon concentrations in houses built on the Pispala esker in the city of Tampere were taken. The objective was to find connections between indoor radon concentrations, esker topography, and meteorological factors. The results show that not only the permeable soil but also subterranean air-flows in the esker strongly affect the indoor radon concentrations. The difference in temperature between the soil air inside the esker and the outdoor air compels the subterranean air to stream between the upper and lower esker areas. In winter, the radon concentrations are amplified in the upper esker areas where air flows out from the esker. In summer, concentrations are amplified in certain slope zones. In addition, wind direction affects the soil air and indoor radon concentrations when hitting the slopes at right angles. Winter-summer concentration ratios are typically in the range of 3-20 in areas with amplified winter concentration, and 0.1-0.5 in areas with amplified summer concentrations. A combination of winter and summer measurements provides the best basis for making mitigation decisions. On eskers special attention must be paid to building technology because of radon. 9 refs., 7 figs., 1 tab.

  9. Hourly indoor radon measurements in a research house.

    PubMed

    Sesana, Lucia; Begnini, Stefania

    2004-01-01

    This paper reports and discusses the behaviour of radon concentration with time in an uninhabited dwelling. The relationship between variations in radon concentrations and indoor-outdoor temperatures and wind intensity has also been discussed. Radon concentration was measured hourly in a house located at a height of 800 m in the Lombard Prealps, at the top of the Valassina valley. The wind velocity and indoor-outdoor temperatures were measured by means of a meteorological station located on the terrace of the house. The data were analysed using the LBL model for indoor-outdoor air exchange and the models for the indoor accumulation of radon due to exhalation from building materials and pressure-driven infiltrations located underground. The role of wind and indoor-outdoor temperatures were analysed. The agreement of measurements with modelling clearly demonstrates the importance of the different sources of indoor radon. As the investigation was conducted in an uninhabited house, the measurements were not affected by the behaviour of people, e.g. opening and closing of windows. Measurements of the outdoor atmospheric concentrations of (222)Rn provide an index of the atmospheric stability, the formation of thermal inversions and convective turbulence.

  10. Thorough investigations on indoor radon in Băiţa radon-prone area (Romania).

    PubMed

    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, 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).

  11. Normal and seasonally amplified indoor radon levels

    SciTech Connect

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

    1995-01-01

    Winter and summer indoor radon measurements are reported for 121 houses in Freehold, New Jersey. When presented as winter:summer ratios of indoor radon, the data closely approximate a lognormal distribution. The geometric mean is 1.49. Freehold is located on the fairly flat coastal plain. The winter:summer ratios are believed to represent the norm for regions of the U.S. with cold winters and hot summers. The Freehold data set can be compared to corresponding data sets from other locations to suggest seasonal perturbations of indoor radon arising from unusual causes.

  12. A study of factors affecting indoor radon properties.

    PubMed

    Yu, K N; Young, E C; Li, K C

    1996-08-01

    The factors affecting indoor radon properties in Hong Kong have been studied, including the radon concentration, the total potential alpha energy concentration of radon progeny, the equilibrium factor, and the fraction of unattached radon progeny. These factors fall into three categories, namely, (1) the building characteristics, including cooling method, age of the buildings, wall coverings and floor coverings; (2) the location of sites, including nearby environments, geological materials of the area, and the elevation of the sites; and (3) the meteorological parameters, including rainfall, relative humidity, pressure, temperature, and wind speeds. For category (1), only the ventilation is found to affect the indoor radon properties. For category (2), only the nearby environments have effects. For category (3), the rainfall and temperature are found to have significant effects.

  13. A study of factors affecting indoor radon properties

    SciTech Connect

    Yu, K.N.; Young, E.C.M.; Li, K.C.

    1996-08-01

    The factors affecting indoor radon properties in Hong Kong have been studied, including the radon concentration, the total potential alpha energy concentration of radon progeny, the equilibrium factor, and the fraction of unattached radon progeny. These factors fall into three categories, namely, (1) the building characteristics, including cooling method, age of the buildings, wall coverings and floor coverings; (2) the location of sites, including nearby environments, geological materials of the area, and the elevation of the sites; and (3) the meteorological parameters, including rainfall, relative humidity, pressure, temperature, and wind speeds. For category (1), only the ventilation is found to affect the indoor radon properties. For category (2), only the nearby environments have effects. For category (3), the rainfall and temperature are found to have significant effects. 15 refs., 1 fig., 5 tabs.

  14. Seasonal Variation or Indoor Radon in Artvin-Turkey

    SciTech Connect

    Yeslbagg, Y. Ue.; Kuecuekoemeroglu, A.; Kurnaz, A.; Uzderya, F.

    2010-01-21

    Indoor radon studies have been conducted in Artvin, Eastern alack sea region of Turkey using SSNTD type nuclear track detector (CR-39). Radon measurements were done for 4 seasons in 73 dwellings, selected as uniformly distributed as possible. The radon concentrations vary from 21 aq m{sup -3} to 321 aq m{sup -3} with the annual mean concentration of 132 aq m{sup -3} for Artvin. Seasonal variation indoor radon shows high in winter low values in summer. The resulting estimated annual effective dose-equivalent due to inhalation of radon for inhabitants is 3.32 mSv y{sup -1} and the total annual effective dose lies in the range of the action level (3-10 mSv y{sup -1}) recommended by the ICRP.

  15. Seasonal Variation or Indoor Radon in Artvin-Turkey

    NASA Astrophysics Data System (ADS)

    Yeşlbagǧ, Y. Ü.; Küçükömeroǧlu, A.; Kurnaz, A.; Uzderya, F.

    2010-01-01

    Indoor radon studies have been conducted in Artvin, Eastern alack sea region of Turkey using SSNTD type nuclear track dedector (CR-39). Radon measurements were done for 4 seasons in 73 dwellings, selected as uniformly distributed as possible. The radon concentrations vary from 21 aq m-3 to 321 aq m-3 with the annual mean concentration of 132 aq m-3 for Artvin. Seasonal variation indoor radon shows high in winter low values in summer. The resulting estimated annual effective dose-equivalent due to inhalation of radon for inhabitants is 3.32 mSv y-1 and the total annual effective dose lies in the range of the action level (3-10 mSv y-1) recommended by the ICRP.

  16. Fluctuation of Indoor Radon and VOC Concentrations Due to Seasonal Variations

    EPA Science Inventory

    This research was conducted to better characterize the spatial and temporal variability of vapor intrusion by collecting a full year’s dataset of weekly measurements of subslab soil gas, external soil gas, and indoor air, on a single house that is impacted by vapor intrusion of r...

  17. Results from time integrated measurements of indoor radon, thoron and their decay product concentrations in schools in the Republic of Macedonia.

    PubMed

    Stojanovska, Zdenka; Zunic, Zora S; Bossew, Peter; Bochicchio, Francesco; Carpentieri, Carmela; Venoso, Gennaro; Mishra, Rosaline; Rout, R P; Sapra, B K; Burghele, Bety D; Cucoş-Dinu, A; Boev, Blazo; Cosma, C

    2014-11-01

    As part of a survey on concentrations of radon, thoron and their decay products in different indoor environments of the Balkan region involving international collaboration, measurements were performed in 43 schools from 5 municipalities of the Republic of Macedonia. The time-integrated radon and thoron gas concentrations (CRn and CTn) were measured by CR-39 (placed in chambers with different diffusion barriers), whereas the equilibrium equivalent radon and thoron concentrations (EERC and EETC) were measured using direct radon-thoron progeny sensors consisting of LR-115 nuclear track detectors. The detectors were deployed at a distance of at least 0.5 m from the walls as well as far away from the windows and doors in order to obtain more representative samples of air from the breathing zone; detectors were exposed over a 3-month period (March-May 2012). The geometric mean (GM) values [and geometric standard deviations (GSDs)] of CRn, CTn, EERC and EETC were 76 (1.7), 12 (2.3), 27 (1.4) and 0.75 Bq m(-3) (2.5), respectively. The equilibrium factors between radon and its decay products (FRn) and thoron and its decay products (FTn (>0.5 m)) were evaluated: FRn ranged between 0.10 and 0.84 and FTn (>0.5 m) ranged between 0.003 and 0.998 with GMs (and GSDs) equal to 0.36 (1.7) and 0.07 (3.4), respectively.

  18. Radon transport in soil and its relation to indoor radioactivity.

    PubMed

    Wilkening, M

    1985-10-01

    The transport of radon from soil to the indoor living space involves diffusion and viscous flow in the soil coupled with transfer to the building interior of radon-rich air which accumulates in cavities and channels below and around the foundations of buildings. Radon concentrations in soil pores at depth are dependent upon the radium content of the soil, emanating power for radium, and soil moisture content. Atmospheric pressure fluctuation, thermal gradients in fractured rocks, and air instabilities due to temperature differences allow air of high radon content to reach living space in dwellings in addition to that which comes directly from building materials and other sources. PMID:4081718

  19. Measurement of soil gas radon and its correlation with indoor radon around some areas of Upper Siwaliks, India.

    PubMed

    Singh, Joga; Singh, Harmanjit; Singh, Surinder; Bajwa, B S

    2010-03-01

    Radon is a radioactive gas which makes the primary contribution to the natural radiation to which people are exposed. For that reason, great importance is attributed to the determination of radon concentration levels in water, indoor air and soil gas and outdoors. In this paper, measurements of radon concentration in soil gas have been carried out around some areas of the Upper Siwaliks of the Kala Amb, Nahan and Morni Hills, India, using a portable AlphaGUARD PQ 2000 device into which the soil gas is drawn using active pumping. The soil gas radon concentration around the Upper Siwaliks was found to vary from 11.5 +/- 0.9 to 78.47 +/- 3.1 kBq m(-3). The annual average indoor radon concentration in the study area was measured in the range from 71.7 +/- 21.0 to 421.7 +/- 33.6 Bq m( - 3) using LR-115 type II cellulose nitrate films in the bare mode. The values of soil gas radon concentration in the study area were compared with those from the adjoining low-radioactive areas of Punjab. Since the soil or bedrock beneath a building is one of the sources of radon gas in the indoor air, an effort has been made to find a possible correlation between soil gas radon with the indoor radon. A satisfactory positive correlation has been observed between soil gas radon and indoor radon in the study area. PMID:20220213

  20. Results Of The National Survey On Radon Indoors In Albania

    NASA Astrophysics Data System (ADS)

    Bode, Kozeta; Bylyku, Elida; Cfarku, Florinda; Mucollari, Irena; Shyti, Manjola

    2010-01-01

    Radon in indoor air originates from trace concentrations of radium in substrate soil and the walls, floor and ceilings which are constructed of building materials [1]. According to the assessments made by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), radon in the natural environment constitutes about 50% of the human exposure to natural radiation or 1, 2 mSv/year [3]. In this paper are given the results of the indoor radon concentration measurement of about 173 dwellings which involving 10 Albanian Regions performed by the Centre of Applied Nuclear Physics. For these measurements were used passive radon detector Radtrack, which provide the average values of indoor radon concentration for 90 days (3 months). Regional averages range from about 23 Bq m-3 to about 278 Bq m-3. However, the uncertainty of regional values can be relevant in case of small Regions, where a low number of small dwellings, although such uncertainties do not affect significantly national values. Based at the results of the measurements, the indoor radon concentrations in the majority of the dwellings were under reference levels (200-400 Bqm-3) [2].

  1. Indoor Radon: The Deadliest Pollutant.

    ERIC Educational Resources Information Center

    Kerr, Richard A.

    1988-01-01

    Describes the origin, occurrence, and effects of radon gas. Cites studies which attribute 5,000 to 20,000 deaths per year to radon exposure and the synergistic effect between radon and smoking. Explains ways to reduce risks. (RT)

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

    NASA Astrophysics Data System (ADS)

    Hadad, Kamal; Mokhtari, Javad

    2015-02-01

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

  3. Radium distribution and indoor radon in the Pacific Northwest

    USGS Publications Warehouse

    Duval, J.S.; Otton, J.K.

    1990-01-01

    Aerial gamma-ray data were compiled to produce a map showing the distribution of radium (226Ra) in near-surface materials in the Pacific Northwest, (Washington, Oregon, and Idaho, and parts of Montana, Wyoming, California, Nevada, and Utah). A comparison of measurements of indoor concentration levels of radon (222Rn) in homes with the apparent surface concentration of radium shows that aerial gamma-ray data provide a first order estimate of the relative amounts of indoor radon for township-sized areas where soils have low to moderate permeability. Townships with average indoor radon levels above the general trend of the data are almost all characterized by soils that have higher intrinsic permeabilities. -Authors

  4. Investigation of Relation Between Outdoor Temperature and Radon Concentration in Buildings

    SciTech Connect

    Muellerova, M.; Holy, K.

    2007-11-26

    The results of measurements of radon concentration variations in two types of buildings in Slovakia are reported. The AlphaGUARD radon monitor was used for continuous monitoring of radon activity concentration in indoor air. The analysis showed that the indoor radon in both buildings had very different responses to outdoor temperature.

  5. Investigation of Relation Between Outdoor Temperature and Radon Concentration in Buildings

    NASA Astrophysics Data System (ADS)

    Müllerová, M.; Holý, K.

    2007-11-01

    The results of measurements of radon concentration variations in two types of buildings in Slovakia are reported. The AlphaGUARD radon monitor was used for continuous monitoring of radon activity concentration in indoor air. The analysis showed that the indoor radon in both buildings had very different responses to outdoor temperature.

  6. Preliminary integrated indoor radon measurements in Transylvania (Romania).

    PubMed

    Cosma, Constantin; Szacsvai, Kinga; Dinu, Alexandra; Ciorba, Daniela; Dicu, Tiberius; Suciu, Liviu

    2009-09-01

    Measurements of indoor radon concentrations were performed in 406 residential houses in five counties (Cluj, Bihor, Alba, Bistrita, and Sibiu) using Makrofol and CR-39 alpha-track detectors. From our measurements, an average indoor radon concentration of 82.5 Bq m(-3) for the Transylvanian population was calculated, i.e. an annual effective dose of 2.4 mSv for the whole body. The calculated dose is 62% higher than that previously reported but yet below the recommended action level of ICRP (International Commission on Radiological Protection). A log-normal distribution of the radon concentration was obtained for the studied counties, excluding some higher values from the Stei region--a radon-prone area in Transylvania. For the Stei region, the data show a dual log-normal distribution of the radon concentration with the second maximum being related to the houses built using uranium waste as a construction material. Assuming a cancer risk coefficient of 10(-4)/100 Bq m(-3) year(-1), one can estimate that about 600 lung cancer per year, for about 7,000,000 inhabitants of the Transylvania region, are due to radon inhalation.

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

    NASA Astrophysics Data System (ADS)

    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.

  8. Passive, integrated measurement of indoor radon using activated carbon.

    PubMed

    George, A C

    1984-04-01

    Activated carbon canisters were tested to determine their adsorption and retention characteristics for radon. Our tests conducted indoors under typical conditions of temperature and relative humidity indicate that simple, inexpensive and maintenance-free passive devices containing 150-200 g of activated carbon can measure radon conveniently and adequately. The amount of radon absorbed in the collector is determined by counting the gamma rays from the decay products of radon. The lower limit of detection for radon is 0.2 pCi/l. for an exposure of 72 hr. Greater sensitivity can be obtained with larger counting systems and devices containing carbon with more surface area. Tests in a residential building and in a test chamber indicate that the measured radon in the canister is proportional to the mean concentration of radon during the period of exposure when correction for relative humidity is made. For practical situations encountered indoors, the device yields results accurate to within +/- 20%. Results from field measurements indicate that the use of the device is feasible.

  9. Indoor Radon Measurements in Mexico City

    SciTech Connect

    Bogard, James S; Espinosa Garcia, Guillermo

    2008-01-01

    Mexico City is one of the most populated cities in the world with almost 22 million inhabitants, located at an altitude of 2200 m. The old city was founded on an ancient lake and the zone is known by its high seismicity; indoor radon determination is an important public health issue. In this paper the data of indoor radon levels in Mexico City, measured independently by two research groups, both using Nuclear Track Detector systems but different methodologies, are correlated. The measurements were done during similar exposure periods of time, at family houses from the political administrative regions of the city. The results indicate a correlation coefficient between the two sets of data of R = 0.886. Most of the differences between the two sets of data are inherent to houses having extreme (very high or very low indoor radon) included in the statistics of each group. The total average indoor radon found in Mexico City considering the two methods was 87 Bq m{sup -3}.

  10. Soil radium, soil gas radon and indoor radon empirical relationships to assist in post-closure impact assessment related to near-surface radioactive waste disposal.

    PubMed

    Appleton, J D; Cave, M R; Miles, J C H; Sumerling, T J

    2011-03-01

    Least squares (LS), Theil's (TS) and weighted total least squares (WTLS) regression analysis methods are used to develop empirical relationships between radium in the ground, radon in soil and radon in dwellings to assist in the post-closure assessment of indoor radon related to near-surface radioactive waste disposal at the Low Level Waste Repository in England. The data sets used are (i) estimated ²²⁶Ra in the < 2 mm fraction of topsoils (eRa226) derived from equivalent uranium (eU) from airborne gamma spectrometry data, (ii) eRa226 derived from measurements of uranium in soil geochemical samples, (iii) soil gas radon and (iv) indoor radon data. For models comparing indoor radon and (i) eRa226 derived from airborne eU data and (ii) soil gas radon data, some of the geological groupings have significant slopes. For these groupings there is reasonable agreement in slope and intercept between the three regression analysis methods (LS, TS and WTLS). Relationships between radon in dwellings and radium in the ground or radon in soil differ depending on the characteristics of the underlying geological units, with more permeable units having steeper slopes and higher indoor radon concentrations for a given radium or soil gas radon concentration in the ground. The regression models comparing indoor radon with soil gas radon have intercepts close to 5 Bq m⁻³ whilst the intercepts for those comparing indoor radon with eRa226 from airborne eU vary from about 20 Bq m⁻³ for a moderately permeable geological unit to about 40 Bq m⁻³ for highly permeable limestone, implying unrealistically high contributions to indoor radon from sources other than the ground. An intercept value of 5 Bq m⁻³ is assumed as an appropriate mean value for the UK for sources of indoor radon other than radon from the ground, based on examination of UK data. Comparison with published data used to derive an average indoor radon: soil ²²⁶Ra ratio shows that whereas the published data are

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

    PubMed

    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.

  12. Indoor radon and lung cancer in China

    SciTech Connect

    Blot, W.J.; Xu, Z.Y.; Boice, J.D. Jr.; Zhao, D.Z.; Stone, B.J.; Sun, J.; Jing, L.B.; Fraumeni, J.F. Jr. )

    1990-06-20

    Radon has long been known to contribute to risk of lung cancer, especially in undergound miners who are exposed to large amounts of the carcinogen. Recently, however, lower amounts of radon present in living areas have been suggested as an important cause of lung cancer. In an effort to clarify the relationship of low amounts of radon with lung cancer risk, we placed alpha-track radon detectors in the homes of 308 women with newly diagnosed lung cancer and 356 randomly selected female control subjects of similar age. Measurements were taken after 1 year. All study participants were part of the general population of Shenyang, People's Republic of China, an industrial city in the northeast part of the country that has one of the world's highest rates of lung cancer in women. The median time of residence in the homes was 24 years. The median household radon level was 2.3 pCi/L of air; 20% of the levels were greater than 4 pCi/L. Radon levels tended to be higher in single-story houses or on the first floor of multiple-story dwellings, and they were also higher in houses with increased levels of indoor air pollution from coal-burning stoves. However, the levels were not higher in homes of women who developed lung cancer than in homes of controls, nor did lung cancer risk increase with increasing radon level. No association between radon and lung cancer was observed regardless of cigarette-smoking status, except for a nonsignificant trend among heavy smokers. No positive associations of lung cancer cell type with radon were observed, except for a nonsignificant excess risk of small cell cancers among the more heavily exposed residents. Our data suggest that projections from surveys of miners exposed to high radon levels may have overestimated the overall risks of lung cancer associated with levels typically seen in homes in this Chinese city.

  13. Radon as an Anthropogenic Indoor Air Pollutant

    NASA Astrophysics Data System (ADS)

    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. Geographical distribution of indoor radon and related geological characteristics in Bonghwa County, a provisional radon-prone area in Korea.

    PubMed

    Lee, E R; Chang, B U; Kim, H J; Song, M H; Kim, Y J

    2015-12-01

    The detailed indoor radon survey was conducted during a year (from September 2012 to August 2013) quarterly in Bonghwa county, one of the provisional radon-prone areas in Korea. The surveyed area was selected on the basis of previously conducted nationwide radon survey results. In order to minimise statistical and environmental uncertainties, ∼3 % of the entire dwellings were carefully selected based on the statistical annual report of Bonghwa county. The measurement is carried out by using solid-state nuclear track detector. The range of indoor radon concentration in each dwelling was 4.36-858 Bq m(-3) and that of annual effective dose due to inhaled radon of the resident in each dwelling was 0.19-23.5 mSv y(-1). Each dwelling was determined for geology criterion using one-way Analysis of Variance for the purpose of comparing indoor radon distribution with geology. Geographical distribution of indoor radon is closely related to the geological characteristics of basement rocks. In addition, the comparison between geographical distribution of indoor radon and terrestrial gamma radiation was done.

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

    PubMed

    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

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

    PubMed

    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

  17. Annual average radon concentrations in California residences.

    PubMed

    Liu, K S; Hayward, S B; Girman, J R; Moed, B A; Huang, F Y

    1991-09-01

    A study was conducted to determine the annual average radon concentrations in California residences, to determine the approximate fraction of the California population regularly exposed to radon concentrations of 4 pCi/l or greater, and to the extent possible, to identify regions of differing risk for high radon concentrations within the state. Annual average indoor radon concentrations were measured with passive (alpha track) samplers sent by mail and deployed by home occupants, who also completed questionnaires on building and occupant characteristics. For the 310 residences surveyed, concentrations ranged from 0.10 to 16 pCi/l, with a geometric mean of whole-house (bedroom and living room) average concentrations of 0.85 pCi/l and a geometric standard deviation of 1.91. A total of 88,000 California residences (0.8 percent) were estimated to have radon concentrations exceeding 4 pCi/l. When the state was divided into six zones based on geology, significant differences in geometric mean radon concentrations were found between several of the zones. Zones with high geometric means were the Sierra Nevada mountains, the valleys east of the Sierra Nevada, the central valley (especially the southern portion), and Ventura and Santa Barbara Counties. Zones with low geometric means included most coastal counties and the portion of the state from Los Angeles and San Bernardino Counties south.

  18. Indoor exposure of population to radon in the FYR of Macedonia.

    PubMed

    Stojanovska, Zdenka; Januseski, Jovan; Boev, Blazo; Ristova, Mimoza

    2012-01-01

    The authors present the results of a year-long survey of the indoor radon concentration levels in the FYR of Macedonia. A total number of 437 dwellings in eight statistical regions were subject to radon concentration measurements by using CR-39 track detectors. The annual mean indoor radon concentration in each measuring site was estimated from the four individual measurements with 3 months duration. The measuring period was from December 2008 to December 2009. The distribution of the results was nearly log-normal. The arithmetic and geometric mean values of the annual mean value of radon concentration were estimated to be 105 ± 84 and 84*/1.9 Bq m(-3), respectively. The annual effective dose due to indoor exposure to radon in the dwellings was estimated to be 2.1*/1.9 mSv y(-1).

  19. Soil-gas and indoor radon distribution related to geology in Frederick County, Maryland

    SciTech Connect

    Szarzi, S.L.; Reimer, G.M.; Been, J.M.

    1992-12-31

    Soil-gas radon concentrations vary in response to geologic controls in Frederick County, Maryland, and the variation leads to different radon availabilities for potential indoor accumulations. Quartzites, which form from the core of ridges and mountains of the southern and western part of the county, have a mean soil-gas radon concentration of 26 kBq m{sup -3} (700 pCi L{sup -1}). Phyllites, found in the Piedmont province in the eastern part of the county, have a mean soil-gas radon concentration of 59 kBq m{sup -3} (1600 pCi L{sup -1}). Many indoor radon measurements for homes in the southeast portion of the county, made by means of charcoal canisters, exceeded 1850 Bq m{sup -3} (50 pCi L{sup -1}). Homes built in areas where the soil-gas radon concentrations were greater than 75 kBq m{sup -3} (2000 pCi L{sup -1}) may have indoor radon concentrations that exceed 150 Bq m{sup -3} (4 pCi L{sup -1}), the current action level recommended by the U.S. Environmental Protection Agency. Data obtained in studies like ours throughout the United States are essential to identify {open_quotes}hot spots{close_quotes} which may produce elevated indoor radon levels of significant risk.

  20. SOME RESULTS FROM THE DEMONSTRATION OF INDOOR RADON REDUCTION MEASURES IN BLOCK BASEMENT HOUSES

    EPA Science Inventory

    Active soil ventilation techniques have been tested in 26 block-wall basement houses in eastern Pennsylvania with significantly elevated indoor radon concentrations, generally above 740 Bq/m3, and the results indicate that radon levels can be reduced substantially often below the...

  1. Radon concentrations in some dwellings of Tunisia.

    PubMed

    El May, Michèle V; Chahed, Neila; Mtimet, Sadok

    2004-02-01

    Indoor air radon concentrations are still unknown in Tunisia. For the first time, they have been determined in several regions of the country using open alpha track dosimeters containing LR-115 film. Measurements were taken in 69 dwellings located around greater Tunis during 1 y, changing dosimeters every 2 mo. In 12 other locations, devices were placed during 2 winter months. The median of 1,217 measurements was 40 Bq m(-3) and 93.4% of them were less than 100 Bq m(-3). The highest concentration was 392 Bq m(-3). In Tunis, concentrations were higher during winter. Indoor air radon figures varied with geographic location: the highest values were found in Jendouba, Gafsa, Beja, and Tataouine government districts where phosphate and lead mines and deposits are present. This first study showed that indoor air radon concentrations are low in Tunisia, but further studies should be performed in localized areas, taking into consideration the geology, the climatic variations, and the building material. PMID:14744048

  2. Assessment of the unattached fraction of indoor radon progeny and its contribution to dose: a pilot study in China.

    PubMed

    Guo, Qiuju; Zhang, Lei; Guo, Lu

    2012-12-01

    The unattached fraction of radon progeny (f(p)) is one of the most important factors for accurate evaluation of the effective dose from a unit of radon exposure, and it may vary greatly in different environments. For precise evaluation of the indoor radon exposure dose and the influence of unattached radon progeny, a pilot survey of f(p) in different environments was carried out in China with a portable and integrating monitor. The dose conversion factors for radon progeny are calculated with LUDEP(®) code, and the dose contributions from the unattached and the attached radon progenies were simultaneously evaluated based on the results of field measurements. The results show that even though the concentrations of radon progeny vary significantly among different indoor environments, the variations of f(p) seem relatively small (9.3-16.9%). The dose contribution from unattached radon progeny is generally larger (30.2-46.2%) in an indoor environment.

  3. Indoor radon measurements in the New York Capital District.

    PubMed

    Fleischer, R L; Turner, L G

    1984-05-01

    Radon-222 concentrations have been measured in 21 "energy-efficient" homes and 14 conventional homes in the New York Capital District. Usual concentrations are averaged over six-month or 12-month periods using solid-state track detectors. Full-year averages are available for 23 of the homes, and the winter-to-summer variations have been observed. In a number of cases, 222Rn emanations from various construction materials and soil samples have been measured and correlations sought with indoor 222Rn. Two major patterns emerge. The living areas of the energy-efficient homes without heat-storage masses have median radon concentrations that are 1.6 times those for conventional homes, and the energy-efficient homes with heat-storage masses have four to five times the 222Rn of conventional homes.

  4. Indoor radon in a Spanish region with different gamma exposure levels.

    PubMed

    Quindós, L S; Fernández, P L; Sainz, C; Fuente, I; Nicolás, J; Quindós, L; Arteche, J

    2008-10-01

    In the beginning of 1990s within the framework of a national radon survey of more than 1500 points, radon measurements were performed in more than 100 houses located in Galicia region, in the Northwest area of Spain. The houses were randomly selected only bearing in mind general geological aspects of the region. Subsequently, a nationwide project called MARNA dealt with external gamma radiation measurements in order to draw a Spanish natural radiation map. The comparison in Galicia between these estimations and the indoor radon levels previously obtained showed good agreement. With the purpose of getting a confirmation of this relationship and also of creating a radon map of the zone, a new set of measurements were carried out in 2005. A total of 300 external gamma radiation measurements were carried out as well as 300 measurements of 226Ra, 232Th and 40K content in soil. Concerning radon, 300 1-m-depth radon measurements in soil were performed, and indoor radon concentration was determined in a total of 600 dwellings. Radon content in soil gave more accurate indoor radon predictions than external gamma radiation or 226Ra concentration in soil.

  5. Comparison of Northern Ireland radon maps based on indoor radon measurements and geology with maps derived by predictive modelling of airborne radiometric and ground permeability data.

    PubMed

    Appleton, J D; Miles, J C H; Young, M

    2011-03-15

    Publicly available information about radon potential in Northern Ireland is currently based on indoor radon results averaged over 1-km grid squares, an approach that does not take into account the geological origin of the radon. This study describes a spatially more accurate estimate of the radon potential of Northern Ireland using an integrated radon potential mapping method based on indoor radon measurements and geology that was originally developed for mapping radon potential in England and Wales. A refinement of this method was also investigated using linear regression analysis of a selection of relevant airborne and soil geochemical parameters from the Tellus Project. The most significant independent variables were found to be eU, a parameter derived from airborne gamma spectrometry measurements of radon decay products in the top layer of soil and exposed bedrock, and the permeability of the ground. The radon potential map generated from the Tellus data agrees in many respects with the map based on indoor radon data and geology but there are several areas where radon potential predicted from the airborne radiometric and permeability data is substantially lower. This under-prediction could be caused by the radon concentration being lower in the top 30 cm of the soil than at greater depth, because of the loss of radon from the surface rocks and soils to air.

  6. Attributable risk of lung cancer deaths due to indoor radon exposure.

    PubMed

    Kim, Si-Heon; Hwang, Won Ju; Cho, Jeong-Sook; Kang, Dae Ryong

    2016-01-01

    Exposure to radon gas is the second most common cause of lung cancer after smoking. A large number of studies have reported that exposure to indoor radon, even at low concentrations, is associated with lung cancer in the general population. This paper reviewed studies from several countries to assess the attributable risk (AR) of lung cancer death due to indoor radon exposure and the effect of radon mitigation thereon. Worldwide, 3-20 % of all lung cancer deaths are likely caused by indoor radon exposure. These values tend to be higher in countries reporting high radon concentrations, which can depend on the estimation method. The estimated number of lung cancer deaths due to radon exposure in several countries varied from 150 to 40,477 annually. In general, the percent ARs were higher among never-smokers than among ever-smokers, whereas much more lung cancer deaths attributable to radon occurred among ever-smokers because of the higher rate of lung cancers among smokers. Regardless of smoking status, the proportion of lung cancer deaths induced by radon was slightly higher among females than males. However, after stratifying populations according to smoking status, the percent ARs were similar between genders. If all homes with radon above 100 Bq/m(3) were effectively remediated, studies in Germany and Canada found that 302 and 1704 lung cancer deaths could be prevented each year, respectively. These estimates, however, are subject to varying degrees of uncertainty related to the weakness of the models used and a number of factors influencing indoor radon concentrations.

  7. Attributable risk of lung cancer deaths due to indoor radon exposure.

    PubMed

    Kim, Si-Heon; Hwang, Won Ju; Cho, Jeong-Sook; Kang, Dae Ryong

    2016-01-01

    Exposure to radon gas is the second most common cause of lung cancer after smoking. A large number of studies have reported that exposure to indoor radon, even at low concentrations, is associated with lung cancer in the general population. This paper reviewed studies from several countries to assess the attributable risk (AR) of lung cancer death due to indoor radon exposure and the effect of radon mitigation thereon. Worldwide, 3-20 % of all lung cancer deaths are likely caused by indoor radon exposure. These values tend to be higher in countries reporting high radon concentrations, which can depend on the estimation method. The estimated number of lung cancer deaths due to radon exposure in several countries varied from 150 to 40,477 annually. In general, the percent ARs were higher among never-smokers than among ever-smokers, whereas much more lung cancer deaths attributable to radon occurred among ever-smokers because of the higher rate of lung cancers among smokers. Regardless of smoking status, the proportion of lung cancer deaths induced by radon was slightly higher among females than males. However, after stratifying populations according to smoking status, the percent ARs were similar between genders. If all homes with radon above 100 Bq/m(3) were effectively remediated, studies in Germany and Canada found that 302 and 1704 lung cancer deaths could be prevented each year, respectively. These estimates, however, are subject to varying degrees of uncertainty related to the weakness of the models used and a number of factors influencing indoor radon concentrations. PMID:26925236

  8. A geographic information systems (GIS) and spatial modeling approach to assessing indoor radon potential at local level.

    PubMed

    Zhou, Joey Y; Laćan, Igor; Liu, Kai-Shen; Waldman, Jed

    2006-04-01

    This study integrates residential radon data from previous studies in Southern California (USA), into a geographic information system (GIS) linked with statistical techniques. A difference (p<0.05) is found in the indoor radon in residences grouped by radon-potential zones. Using a novel Monte Carlo approach, we found that the mean distance from elevated-radon residences (concentration>74 Bq m(-3)) to epicenters of large (> 4 Richter) earthquakes was smaller (p<0.0001) than the average residence-to-epicenter distance, suggesting an association between the elevated indoor-radon and seismic activities.

  9. Indoor radon measurements in Erzurum province of Turkey

    NASA Astrophysics Data System (ADS)

    Durak, R.; Kiran, D.; Kavaz, E.; Ekinci, N.

    2016-04-01

    Indoor radon measurements were carried out in dwellings in Erzurum province during the winter months of February 2012 to early April 2012 and the summer months of July 2012 to early September 2012. Nuclear track detector LR-115 was used for the measurements. According to the results of investigations, it was understood that the indoor radon concentration averages in dwellings are in the range of 11 ± 6 Bq m-3 - 380 ± 91 Bq m-3 in winter season and 8 ± 3 Bq m-3 - 356 ± 64 Bq m-3 in summer season. We found that the 222Rn effective dose values in the studied dwellings in winter season range from 0.278 to 9.59 mSv y-1. Also, the 222Rn effective dose values in the studied dwellings in summer season range from 0.202 to 8.98 mSv y-1. These values are within the ICPR recommended values. The radon activity has not been found to vary with seasonal changes, but also with the age, the construction mode of houses, the ventilation conditions and with specific sites and geological materials.

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Radium-226 concentration in spring water sampled in high radon regions.

    PubMed

    Onishchenko, Aleksandra; Zhukovsky, Michael; Veselinovic, Nenad; Zunic, Zora S

    2010-01-01

    Water (226)Ra concentration in springs was measured in regions with high indoor radon: Ural, North Caucasus (Russia), Niska Banja (Serbia), Piestany (Slovakia), and Issyk-Kul (Kyrgyzstan). This paper presents the results for (226)Ra concentration above 0.03 Bq l(-1). Radium in water could indicate indoor radon problem in the region and water investigation is useful at the initial stage of radon survey. Even low (226)Ra concentration in water (0.1-0.6 Bq l(-1)) caused high (226)Ra activity in travertine (up to 1500 Bq kg(-1)), which resulted in indoor radon concentration above 2000 Bq m(-3) (Niska Banja). PMID:19853463

  12. Exposure to radon and radon progeny in the indoor environment. Final report

    SciTech Connect

    Socolow, R.H.

    1994-10-01

    This report discusses the work done by the Center for Energy and Environmental Studies at Princeton University as part of the radon research program. It involves radon measurements in various buildings, as well as the use of natural ventilation to mitigate radon levels. The report is divided into four chapters: The use of radon entry rate measurements to understand radon concentration in buildings; Use of natural basement ventilation to control radon in single family dwellings; The effect of natural ventilation on radon and radon progeny levels in houses; and Comparison of natural and forced ventilation for radon mitigation in houses.

  13. Reducing the risks from radon indoors: an IAEA perspective.

    PubMed

    Boal, T; Colgan, P A

    2014-07-01

    The IAEA has a mandate to develop, in collaboration with other relevant international organisations, 'standards of safety for protection of health and minimisation of danger to life and property', and to provide for the application of these standards. The most recent edition of the International Basic Safety Standards includes, for the first time, requirements to protect the public from exposure due to radon indoors. As a result, the IAEA has already developed guidance material in line with accepted best international practice and an international programme to assist its Member States in identifying and addressing high radon concentrations in buildings is being prepared. This paper overviews the current situation around the world and summarises the management approach advocated by the IAEA. A number of important scientific and policy issues are identified and discussed from the point-of-view of how they may impact on national action plans and strategies. Finally, the assistance and support available through the Agency is described.

  14. Estimation of the indoor radon and the annual effective dose from granite samples

    NASA Astrophysics Data System (ADS)

    Sola, P.; Srinuttrakul, W.; Kewsuwan, P.

    2015-05-01

    Inhalation of radon and thoron daughters increases the risk of lung cancer. The main sources of indoor radon are building materials. The aim of this research is to estimate the indoor radon and the annual effective dose from the building materials. Eighteen granite samples bought from the markets in Thailand were measured using an ionization chamber (ATMOS 12 DPX) for the radon concentration in air. Radon exhalation rates were calculated from the radon concentration in chamber. The indoor radon from the granite samples ranged from 10.04 to 55.32 Bq·m-2·h-1 with an average value of 20.30 Bq·m-2·h-1 and the annual effective dose ranged from 0.25 to 1.39 mSv·y-1 with an average value of 0.48 mSv·y-1. The results showed that the annual effective doses of three granite samples were higher than the annual exposure limit for the general public (1 mSv·y-1) recommended by the International Commission on Radiological Protection (ICRP). In addition, the relationship between the colours and radon exhalation rates of granite samples was also explained.

  15. Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.

    PubMed

    Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C

    2015-11-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. PMID:25920794

  16. Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.

    PubMed

    Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C

    2015-11-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions.

  17. Exposure to indoor radon and natural gamma radiation in some workplaces at Algiers, Algeria.

    PubMed

    Aït Ziane, M; Lounis-Mokrani, Z; Allab, M

    2014-07-01

    Radon activity concentrations have been measured in 34 workplaces throughout Algiers nuclear research centre, in Algeria, during some periods between March 2007 and June 2013 using Electret ion chambers, nuclear tracks detectors and an AlphaGuard system. The indoor radon levels range from 2 to 628 Bq m(-3) with an average indoor concentration equals to 92 Bq m(-3), whereas the estimated outdoor radon concentrations range from 2 to 14 Bq m(-3) with an average value of 6 Bq m(-3). This study also focused on parameters affecting radon concentration levels such as floor number, ventilation and atmospheric parameters. Furthermore, the mean gamma rates have been measured in the different investigated locations and have been found to be varying between 33 and 3300 nSv h(-1). The annual effective dose for workers calculated using the appropriate equilibrium and occupancy factors is lower than the value recommended by International Commission on Radiological Protection in its Publication 103.

  18. An indoor radon survey of the X-ray rooms of Mexico City hospitals

    NASA Astrophysics Data System (ADS)

    Juárez, Faustino; Reyes, Pedro G.; Espinosa, Guillermo

    2013-07-01

    This paper presents the results of measurements of indoor radon concentrations in the X-ray rooms of a selection of hospitals in the metropolitan area of Mexico City. The metropolitan area of Mexico City is Mexico's largest metropolitan area by population; the number of patients requiring the use of X-rays is also the highest. An understanding of indoor radon concentrations in X-ray rooms is necessary for the estimation of the radiological risk to which patients, radiologists and medical technicians are exposed. The indoor radon concentrations were monitored for a period of six months using nuclear track detectors (NTD) consisting of a closed-end cup system with CR-39 (Lantrack®) polycarbonate as detector material. The indoor radon concentrations were found to be between 75 and 170 Bq m-3, below the USEPA-recommended indoor radon action level for working places of 400 Bq m-3. It is hoped that the results of this study will contribute to the establishment of recommended action levels by the Mexican regulatory authorities responsible for nuclear safety.

  19. An indoor radon survey of the X-ray rooms of Mexico City hospitals

    SciTech Connect

    Juarez, Faustino; Reyes, Pedro G.; Espinosa, Guillermo

    2013-07-03

    This paper presents the results of measurements of indoor radon concentrations in the X-ray rooms of a selection of hospitals in the metropolitan area of Mexico City. The metropolitan area of Mexico City is Mexico's largest metropolitan area by population; the number of patients requiring the use of X-rays is also the highest. An understanding of indoor radon concentrations in X-ray rooms is necessary for the estimation of the radiological risk to which patients, radiologists and medical technicians are exposed. The indoor radon concentrations were monitored for a period of six months using nuclear track detectors (NTD) consisting of a closed-end cup system with CR-39 (Lantrack Registered-Sign ) polycarbonate as detector material. The indoor radon concentrations were found to be between 75 and 170 Bq m{sup -3}, below the USEPA-recommended indoor radon action level for working places of 400 Bq m{sup -3}. It is hoped that the results of this study will contribute to the establishment of recommended action levels by the Mexican regulatory authorities responsible for nuclear safety.

  20. Indoor radon measurements in the uranium regions of Poli and Lolodorf, Cameroon.

    PubMed

    Saïdou; Abdourahimi; Tchuente Siaka, Y F; Bouba, O

    2014-10-01

    The objective of this work is to carry out indoor radon measurements in the uranium regions of Poli and Lolodorf in which lie the uranium deposits of Kitongo and Lolodorf, prior to their impending exploitation. The indoor radon concentration was measured in 103 and 50 dwellings located respectively in Poli and Lolodorf using E-PERM electret chamber detectors. Indoor radon distributions in Poli and Lolodorf follow the lognormal law. Radon concentrations range respectively in Poli and Lolodorf between 29 and 2240 Bq m(-3) and 24-4390 Bq m(-3) with corresponding median values of 165 Bq m(-3) and 331 Bq m(-3). Corresponding arithmetic and geometric means are respectively 294 Bq m(-3) and 200 Bq m(-3) for the uranium region of Poli, 687 Bq m(-3) and 318 Bq m(-3) for the uranium region of Lolodorf. For the uranium region of Poli, 80% of dwellings have radon concentration above the reference level of 100 Bq m(-3) and 20% of dwellings show a radon concentration above 300 Bq m(-3). For the uranium region of Lolodorf, 80% of dwellings have radon concentration above 100 Bq m(-3) and 50% of dwellings show a radon concentration above 300 Bq m(-3). Thus radon monitoring and mitigation plan are required to better protect people against harmful effects of radon. PMID:24878718

  1. Indoor radon measurements in the uranium regions of Poli and Lolodorf, Cameroon.

    PubMed

    Saïdou; Abdourahimi; Tchuente Siaka, Y F; Bouba, O

    2014-10-01

    The objective of this work is to carry out indoor radon measurements in the uranium regions of Poli and Lolodorf in which lie the uranium deposits of Kitongo and Lolodorf, prior to their impending exploitation. The indoor radon concentration was measured in 103 and 50 dwellings located respectively in Poli and Lolodorf using E-PERM electret chamber detectors. Indoor radon distributions in Poli and Lolodorf follow the lognormal law. Radon concentrations range respectively in Poli and Lolodorf between 29 and 2240 Bq m(-3) and 24-4390 Bq m(-3) with corresponding median values of 165 Bq m(-3) and 331 Bq m(-3). Corresponding arithmetic and geometric means are respectively 294 Bq m(-3) and 200 Bq m(-3) for the uranium region of Poli, 687 Bq m(-3) and 318 Bq m(-3) for the uranium region of Lolodorf. For the uranium region of Poli, 80% of dwellings have radon concentration above the reference level of 100 Bq m(-3) and 20% of dwellings show a radon concentration above 300 Bq m(-3). For the uranium region of Lolodorf, 80% of dwellings have radon concentration above 100 Bq m(-3) and 50% of dwellings show a radon concentration above 300 Bq m(-3). Thus radon monitoring and mitigation plan are required to better protect people against harmful effects of radon.

  2. Surface-deposition and distribution of the radon-decay products indoors.

    PubMed

    Espinosa, G; Tommasino, L

    2015-05-01

    The exposure to radon-decay products is of great concern both in dwellings and workplaces. The model to estimate the lung dose refers to the deposition mechanisms and particle sizes. Unfortunately, most of the dose data available are based on the measurement of radon concentration and the concentration of radon decay products. These combined measurements are widely used in spite of the fact that accurate dose assessments require information on the particle deposition mechanisms and the spatial distribution of radon decay products indoors. Most of the airborne particles and/or radon decay products are deposited onto indoor surfaces, which deposition makes the radon decay products unavailable for inhalation. These deposition processes, if properly known, could be successfully exploited to reduce the exposure to radon decay products. In spite of the importance of the surface deposition of the radon decay products, both for the correct evaluation of the dose and for reducing the exposure; little or no efforts have been made to investigate these deposition processes. Recently, two parallel investigations have been carried out in Rome and at Universidad Nacional Autónoma de México (UNAM) in Mexico City respectively, which address the issue of the surface-deposited radon decay products. Even though these investigations have been carried independently, they complement one another. It is with these considerations in mind that it was decided to report both investigations in the same paper. PMID:25748340

  3. Surface-deposition and Distribution of the Radon (222Rn and 220Rn) Decay Products Indoors

    NASA Astrophysics Data System (ADS)

    Espinosa, G.; Tommasino, Luigi

    The exposure to radon (222Rn and 220Rn) decay products is of great concern both in dwellings and workplaces. The model to estimate the lung dose refers to the deposition mechanisms and particle sizes. Unfortunately, most of the dose data available are based on the measurement of radon concentration and the concentration of radon decay products. These combined measurements are widely used in spite of the fact that accurate dose assessments require information on the particle deposition mechanisms and the spatial distribution of radon decay products indoors. Most of the airborne particles and/or radon decay products are deposited onto indoor surfaces, which deposition makes the radon decay products unavailable for inhalation. These deposition processes, if properly known, could be successfully exploited to reduce the exposure to radon decay products. In spite of the importance of the surface deposition of the radon decay products, both for the correct evaluation of the dose and for reducing the exposure, little or no efforts have been made to investigate these deposition processes. Recently, two parallel investigations have been carried out in Rome and at Universidad Nacional Autónoma de México (UNAM) in Mexico City respectively, which address the issue of the surface-deposited radon decay products. Even though these investigations have been carried independently, they complement one another. It is with these considerations in mind that it was decided to report both investigations in the same paper.

  4. Surface-deposition and distribution of the radon-decay products indoors.

    PubMed

    Espinosa, G; Tommasino, L

    2015-05-01

    The exposure to radon-decay products is of great concern both in dwellings and workplaces. The model to estimate the lung dose refers to the deposition mechanisms and particle sizes. Unfortunately, most of the dose data available are based on the measurement of radon concentration and the concentration of radon decay products. These combined measurements are widely used in spite of the fact that accurate dose assessments require information on the particle deposition mechanisms and the spatial distribution of radon decay products indoors. Most of the airborne particles and/or radon decay products are deposited onto indoor surfaces, which deposition makes the radon decay products unavailable for inhalation. These deposition processes, if properly known, could be successfully exploited to reduce the exposure to radon decay products. In spite of the importance of the surface deposition of the radon decay products, both for the correct evaluation of the dose and for reducing the exposure; little or no efforts have been made to investigate these deposition processes. Recently, two parallel investigations have been carried out in Rome and at Universidad Nacional Autónoma de México (UNAM) in Mexico City respectively, which address the issue of the surface-deposited radon decay products. Even though these investigations have been carried independently, they complement one another. It is with these considerations in mind that it was decided to report both investigations in the same paper.

  5. Indoor radon levels in selected hot spring hotels in Guangdong, China.

    PubMed

    Song, Gang; Zhang, Boyou; Wang, Xinming; Gong, Jingping; Chan, Daniel; Bernett, John; Lee, S C

    2005-03-01

    Guangdong is one of the provinces that have most hot springs in China, and many hotels have been set up near hot springs, with spring water introduced into the bath inside each hotel room for hot spring bathing to attract tourists. In the present study, we measured radon in indoor and outdoor air, as well as in hot spring waters, in four hot spring hotels in Guangdong by using NR-667A (III) continuous radon detector. Radon concentrations ranged 53.4-292.5 Bq L(-1) in the hot spring water and 17.2-190.9 Bq m(-3) in outdoor air. Soil gas intrusion, indoor hot spring water use and inefficient ventilation all contributed to the elevated indoor radon levels in the hotel rooms. From the variation of radon levels in closed unoccupied hotel rooms, soil gas intrusion was found to be a very important source of indoor radon in hotel rooms with floors in contact with soils. When there was spring water bathing in the bathes, average radon levels were 10.9-813% higher in the hotel rooms and 13.8-489% higher in bathes compared to their corresponding average levels when there was no spring water use. Spring water use in the hotel rooms had radon transfer coefficients from 1.6x10(-4) to 5.0x10(-3). Radon in some hotel rooms maintained in concentrations much higher than guideline levels might thus have potential health risks to the hotel workers, and technical and management measures should be taken to lower their exposure of radon through inhalation.

  6. Potential lung cancer risk from indoor radon exposure

    SciTech Connect

    Harley, N.H.; Harley, J.H. )

    1990-09-01

    The contribution of radon daughter exposure to excess lung cancer in underground miners is universally accepted. These miners received exposures from tens to thousands of WLM in a relatively few years. Although the miners were also exposed to other noxious agents in mines, the appearance of the excess lung cancer mortality in several types of mines and the increase with increasing exposure provide convincing evidence of the role of radon as the carcinogen. It is conceivable that exposures to radon at an average concentration of one to two pCi/liter, the levels for a majority of homes, might not produce excess lung cancers. This would require that a lifetime exposure at low concentrations produce a different response from that of a few years at higher levels for the miners. This is unlikely but not impossible. The current environmental epidemiology is of varying quality. The better studies may give some answers in a few years. These studies are more likely to establish an upper limit of risk than to provide an exposure-response model. Present risk estimates cannot be used accurately in estimating the overall lung cancer risk to the US population, since there are no good data on average exposure and exposure distribution. For example, the number of homes above the EPA guideline of four pCi/liter may range from two million to 10 million. An estimate of the actual radon exposure in the US may be forthcoming from a planned EPA survey, but these data will not be available for a few years. In the conservative tradition of radiation protection, indoor radon exposures in homes are estimated to produce a number of excess lung cancers in the population.22 references.

  7. Active-passive measurements and CFD based modelling for indoor radon dispersion study.

    PubMed

    Chauhan, Neetika; Chauhan, R P

    2015-06-01

    Computational fluid dynamics (CFD) play a significant role in indoor pollutant dispersion study. Radon is an indoor pollutant which is radioactive and inert gas in nature. The concentration level and spatial distribution of radon may be affected by the dwelling's ventilation conditions. Present work focus at the study of indoor radon gas distribution via measurement and CFD modeling in naturally ventilated living room. The need of the study is the prediction of activity level and to study the effect of natural ventilation on indoor radon. Two measurement techniques (Passive measurement using pin-hole dosimeters and active measurement using continuous radon monitor (SRM)) were used for the validation purpose of CFD results. The CFD simulation results were compared with the measurement results at 15 points, 3 XY planes at different heights along with the volumetric average concentration. The simulation results found to be comparable with the measurement results. The future scope of these CFD codes is to study the effect of varying inflow rate of air on the radon concentration level and dispersion pattern.

  8. Measurement and distribution of radon and radon progeny: An overview of indoor-radon risk reduction in the United States

    SciTech Connect

    Osborne, M.; Harrison, J.

    1992-01-01

    The paper presents an overview of indoor radon risk reduction in the U.S. EPA currently estimates that 15,000-20,000 Americans die each year from radon-induced lung cancer. The estimate is based on epidemiological data which establish the link between radon and lung cancer, and surveys which provide estimates of radon exposure to the American public. EPA and state cosponsored radon surveys conducted in 34 states have indicated that houses with elevated radon levels exist in all parts of the U.S. These surveys have also indicated that radon levels in individual houses cannot be predicted with any degree of accuracy with existing methods. Individual houses must be tested. Based on these surveys, the EPA estimates that up to 8 million houses have annual average radon levels in the living area which exceed EPA's action guideline of 150 Bq/cu m. Responding to the great health risk posed by indoor radon, EPA, through its comprehensive Radon Action Program, has focused on many activities designed to reduce risk to the public from indoor radon. Key activities in the effort include the research and development of risk-reduction technology and the transfer of the technology to state and local governments, private sector industry, and the public.

  9. Long- and short-term indoor radon survey in the Ardea municipality, south Rome.

    PubMed

    Franci, Daniele; Aureli, Tommaso

    2014-12-01

    The indoor radon concentration was measured in 16 schools and 6 public departments in the Ardea municipality, using both active and passive detectors. The annual concentration of radon has been determined as the mean of two consecutive 6-month periods of sampling from January 2012 to January 2013. The indoor radon level measured in the monitored buildings ranged from 17 to 918 Bq·m(-3), with a mean value of 154 Bq·m(-3). In addition, the correlation between short-term and long-term measurements was studied. Experimental data demonstrate that the deviation of short-term measurements with respect to polyallyl diglycol carbonate data does not exceed ±40 % in a very extended range of radon concentrations.

  10. A Comparative Study of Indoor Radon Contributed by Diffusive and Advective Transport through Intact Concrete

    NASA Astrophysics Data System (ADS)

    Chauhan, R. P.; Kumar, Amit

    The present work is aimed that out of diffusive and advective transport which is dominant process for indoor radon entry under normal room conditions. For this purpose the radon diffusion coefficient and permeability of concrete were measured by specially designed experimental set up. The radon diffusion coefficient of concrete was measured by continuous radon monitor. The measured value was (3.78 ± 0.39)×10-8 m2/s and found independent of the radon gas concentration in source chamber. The radon permeability of concrete varied between 1.85×10-17 to 1.36×10-15 m2 for the bulk pressure difference fewer than 20 Pa to 73.3 kPa. From the measured diffusion coefficient and absolute permeability, the radon flux from the concrete surface having concentrations gradient 12-40 kBq/m3 and typical floor thickness 0.1 m was calculated by the application of Fick and Darcy laws. Using the measured flux attributable to diffusive and advective transport, the indoor radon concentration for a typical Indian model room having dimension (5×6×7) m3 was calculated under average room ventilation (0.63 h-1). The results showed that the contribution of diffusive transport through intact concrete is dominant over the advective transport, as expected from the low values of concrete permeability.

  11. Energy-efficient reconstructions and indoor radon: the impact assessed by CDs/DVDs.

    PubMed

    Pressyanov, Dobromir; Dimitrov, Dimitar; Dimitrova, Ivelina

    2015-05-01

    Recent modelling suggests that the expense of energy-efficient building reconstructions can be the enhanced indoor radon levels and the related adverse health impact. Here we show that a couple of home-stored CDs/DVDs can be used to check by direct measurements whether a significant change in radon level occurred in the past after building reconstruction. Radon is continuously absorbed in the polycarbonate material of CDs/DVDs and its average concentration can be determined by etching alpha tracks at a certain depth in the disk. With two disks, one bought before and one after the reconstruction, a change in radon concentration can be detected retrospectively. Within a pilot study of 20 rooms in 16 buildings that underwent energy-efficient interventions years in the past, we observed significant increase in radon concentration (at 95% confidence level) in 35% of the cases, and no case with significant decrease. Direct indication of a radon problem emerged after some of the energy-efficient building interventions was observed. The CD/DVD based approach provides a tool for assessment of the effect of different energy-efficient reconstruction approaches on indoor radon in very short terms and could be useful for finding radon-safe energy-efficient options.

  12. Assessment of indoor radon doses received by the students in the Azad Kashmir schools, Pakistan.

    PubMed

    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.

  13. From the European indoor radon map towards an atlas of natural radiation.

    PubMed

    Tollefsen, T; Cinelli, G; Bossew, P; Gruber, V; De Cort, M

    2014-11-01

    In 2006, the Joint Research Centre of the European Commission launched a project to map radon at the European level, as part of a planned European Atlas of Natural Radiation. It started with a map of indoor radon concentrations. As of May 2014, this map includes data from 24 countries, covering a fair part of Europe. Next, a European map of geogenic radon, intended to show 'what earth delivers' in terms of radon potential (RP), was started in 2008. A first trial map has been created, and a database was established to collect all available data relevant to the RP. The Atlas should eventually display the geographical distribution of physical quantities related to natural radiation. In addition to radon, it will comprise maps of quantities such as cosmic rays and terrestrial gamma radiation. In this paper, the authors present the current state of the radon maps and the Atlas.

  14. Studies of indoor radon and lung cancer risk

    SciTech Connect

    Lubin, J.H.

    1997-03-01

    Epidemiologic case-control studies reported to date have not consistently shown an association between indoor radon and lung cancer risk, even though studies of radon-exposed underground miners have conclusively shown that exposure to radon and its progeny causes lung cancer. Some have interpreted this seeming inconsistency as evidence that exposure to radon at the levels typically found in homes does not cause lung cancer; that exposure in homes causes lung cancer but not to the extent estimated from miner-based risk models; or that risk among miners is dominated by smoking or by other exposures, and miner-based risk models are therefore not relevant to residential exposures. The inconsistency of results has led to claims that indoor radon may not pose a significant public health hazard and that current risk management approaches may not be justified. This paper examines current indoor radon studies. Results from current studies are presented, and then followed by computer simulations, which illustrate the impact of mobility and exposure misclassification. Finally, results of a meta-analysis of indoor studies are presented that suggest that RRs are consistent with miner-based extrapolations and with a small excess risk from indoor exposures, but that there remains unexplained heterogeneity among the studies.

  15. Indoor air-assessment: Indoor concentrations of environmental carcinogens

    SciTech Connect

    Gold, K.W.; Naugle, D.F.; Berry, M.A.

    1991-01-01

    In the report, indoor concentration data are presented for the following general categories of air pollutants: radon-222, environmental tobacco smoke (ETS), asbestos, gas phase organic compounds, formaldehyde, polycyclic aromatic hydrocarbons (PAH), pesticides, and inorganic compounds. These pollutants are either known or suspect carcinogens (i.e., radon-222, asbestos) or more complex mixtures or classes of compounds which contain known or suspect carcinogens. Concentration data for individual carcinogenic compounds in complex mixtures are usually far from complete. The data presented for complex mixtures often include compounds which are not carcinogenic or for which data are insufficient to evaluate carcinogenicity. Their inclusion is justified, however, by the possibility that further work may show them to be carcinogens, cocarcinogens, initiators or promotors, or that they may be employed as markers (e.g., nicotine, acrolein) for the estimation of exposure to complex mixtures.

  16. Nanomaterial Containing Wall Paints Can Increase Radon Concentration in Houses Located in Radon Prone Areas

    PubMed Central

    Haghani, M.; Mortazavi, S. M. J.; Faghihi, R.; Mehdizadeh, S.; Moradgholi, J.; Darvish, L.; Fathi-Pour, E.; Ansari, L.; Ghanbar-pour, M. R.

    2013-01-01

    Background: Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m–3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. Objective: This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Methods: Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Results: Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m3 while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m3. The difference between these means was statistically significant (P<0.001). Conclusion: To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes. PMID:25505754

  17. How serious is the indoor radon health hazard

    SciTech Connect

    Not Available

    1987-08-07

    While cure seekers apparently skeptical of legitimate medicine pay up to $4 per hour to partake of the putative benefits of radon gas in played-out uranium mines in the west, many Americans on the eastern seaboard and elsewhere, also with good health in mind, spend thousands of dollars to rid their own homes of the very same effusion. Last month, the US Senate passed a bill that will help states set up programs to survey and monitor radon concentration in homes and schools. It calls for spending $31.5 million over three years. A similar bill is pending in the House. concern focuses on the fact that up to 20,000 cases of lung cancer annually in this country have been attributed to this inchoate enemy. The trouble is that the assertion, which sounds so reasonable, cannot - so far - be proved. Scientists in various countries at different times have attributed indoor radon to building materials, tap water, and/or soil emissions. The latter view prevails at present.

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

    PubMed

    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. PMID:25827573

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

    PubMed

    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.

  20. Radon Concentration by SSNTD in South-East Sicily Buildings

    NASA Astrophysics Data System (ADS)

    Immè, G.; Catalano, R.; Gianino, C.; Filincieri, R.; Mangano, G.; Morelli, D.

    Radon levels in buildings vary widely from area to area also depending on local geology. Thus, it is important to assess the radon prone area of a geographic region on the basis of geological data and to search for any possible correlation between the local geology and the indoor radon concentrations. We report about indoor radon measurements in Ragusa, a municipality of the SE Sicily, placed in the Hyblean Plateau (northern region of the African Plate), carried out in collaboration with schools. The survey was performed using Solid State Nuclear Track Detectors (SSNTD), CR-39 type, and a well-established methodology for chemical etching and reading, developed at the Radioactivity Laboratory of the Department of Physics - University of Catania.

  1. Simultaneous measurements of indoor radon, radon-thoron progeny and high-resolution gamma spectrometry in Greek dwellings.

    PubMed

    Clouvas, A; Xanthos, S; Antonopoulos-Domis, M

    2006-01-01

    Simultaneous indoor radon, radon-thoron progeny and high-resolution in situ gamma spectrometry measurements, with portable high-purity Ge detector were performed in 26 dwellings of Thessaloniki, the second largest town of Greece, during March 2003-January 2005. The radon gas was measured with an AlphaGUARD ionisation chamber (in each of the 26 dwellings) every 10 min, for a time period between 7 and 10 d. Most of the values of radon gas concentration are between 20 and 30 Bq m(-3), with an arithmetic mean of 34 Bq m(-3). The maximum measured value of radon gas concentration is 516 Bq m(-3). The comparison between the radon gas measurements, performed with AlphaGUARD and short-term electret ionisation chamber, shows very good agreement, taking into account the relative short time period of the measurement and the relative low radon gas concentration. Radon and thoron progeny were measured with a SILENA (model 4s) instrument. From the radon and radon progeny measurements, the equilibrium factor F could be deduced. Most of the measurements of the equilibrium factor are within the range 0.4-0.5. The mean value of the equilibrium factor F is 0.49 +/- 0.10, i.e. close to the typical value of 0.4 adopted by UNSCEAR. The mean equilibrium equivalent thoron concentration measured in the 26 dwellings is EEC(thoron) = 1.38 +/- 0.79 Bq m(-3). The mean equilibrium equivalent thoron to radon ratio concentration, measured in the 26 dwellings, is 0.1 +/- 0.06. The mean total absorbed dose rate in air, owing to gamma radiation, is 58 +/- 12 nGy h(-1). The contribution of the different radionuclides to the total indoor gamma dose rate in air is 38% due to 40K, 36% due to thorium series and 26% due to uranium series. The annual effective dose, due to the different source terms (radon, thoron and external gamma radiation), is 1.05, 0.39 and 0.28 mSv, respectively. PMID:16410290

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

    NASA Astrophysics Data System (ADS)

    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

  3. Anomalously high radon concentrations in dwellings located on permeable glacial sediments.

    PubMed

    Sundal, A V; Jensen, C L; Anestad, K; Strand, T

    2007-09-01

    Indoor radon concentrations were measured in different seasons in 104 dwellings located on a highly permeable ice-marginal moraine in Kinsarvik, Western Norway. The measurements revealed the highest indoor radon levels ever detected in Norway and extreme variations in seasonal and short-term indoor radon levels. Annual average indoor radon concentrations up to 56 000 Bq m(-3) and a mean value of 4340 Bq m(-3) for the whole residential area are reported. By using the ICRP conversion factors to effective dose, these indoor radon values correspond to a total annual effective dose of 930 mSv and 72 mSv, respectively. By using the conversion as recommended by UNSCEAR, the effective doses would be about 50% higher. The indoor radon concentrations are found to be strongly influenced by thermally induced flows of radon-bearing soil air directed towards the upper part of the ice-marginal deposit in winter and towards the area of lowest elevation in summer. The pattern of seasonal variations observed suggests that in areas where thermal convection may occur, annual average indoor radon levels should be derived from measurements performed both in summer and in winter.

  4. Lung Cancer Attributable to Indoor Radon Exposures in Two Radon--Prone Areas, Stei (Romania) and Torrelodones (Spain)

    SciTech Connect

    Dinu, Alexandra; Cosma, Constantin; Vasiliniuc, Stefan; Sainz, Carlos; Poncela, Luis Santiago Quindos

    2009-05-22

    Radon and radon progeny are present indoors, in houses and others dwellings, representing the most important contribution to dose from natural sources of radiation. Most studies have demonstrated an increased risk of lung cancer at high concentration of radon for both smokers and nonsmokers. For medium and low concentrations which are the typical residential radon levels, recent researches have also demonstrated increased risks of lung cancer for people exposed. The work presents a comparative analysis of the radon exposure data in the two radon--prone areas, Stei, Transylvania, (Romania), in the near of old Romanian uranium mines and in the granitic area of Torrelodones town, Sierra de Guadarrama (Spain). One important difference between the two studied areas is related to the houses built using uranium waste as construction material in Stei area. Measurements of indoor radon were performed in 280 dwellings (Romania) and 91 dwellings (Spain) by using nuclear track detectors, CR 39. The highest value measured in Stei area was 2650 Bq{center_dot}m{sup -3}. and 366 Bq{center_dot}m{sup -3} in the Spanish region. The results are compute with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bq{center_dot}m{sup -3}. A total of 233 lung cancer deaths were calculated in the Stei area for a period of 13 years (1994-2006), which is 116.82% higher than observed from the national statistics. In comparison, in Torrelodones area, a number of 276 deaths caused by lung cancer were estimated along a period of 13 years, which is 2.09 times higher than the number observed by authorities. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure.

  5. Air radon concentration decrease in a waste water treatment plant.

    PubMed

    Juste, B; Ortiz, J; Verdú, G; Martorell, S

    2015-06-01

    (222)Rn is a naturally occurring gas created from the decay of (226)Ra. The long-term health risk of breathing radon is lung cancer. One particular place where indoor radon concentrations can exceed national guidelines is in wastewater treatment plants (WWTPs) where treatment processes may contribute to ambient airborne concentrations. The aim of this paper was to study the radon concentration decrease after the application of corrective measures in a Spanish WWTP. According to first measures, air radon concentration exceeded International Commission Radiologica1 Protection (ICRP) normative (recommends intervention between 400 and 1000 Bq m(-3)). Therefore, the WWTP improved mechanical forced ventilation to lower occupational exposure. This measure allowed to increase the administrative controls, since the limitation of workers access to the plant changed from 2 h d(-1) (considering a maximum permissible dose of 20 mSv y(-1) averaged over 5 y) to 7 h d(-1).

  6. Air radon concentration decrease in a waste water treatment plant.

    PubMed

    Juste, B; Ortiz, J; Verdú, G; Martorell, S

    2015-06-01

    (222)Rn is a naturally occurring gas created from the decay of (226)Ra. The long-term health risk of breathing radon is lung cancer. One particular place where indoor radon concentrations can exceed national guidelines is in wastewater treatment plants (WWTPs) where treatment processes may contribute to ambient airborne concentrations. The aim of this paper was to study the radon concentration decrease after the application of corrective measures in a Spanish WWTP. According to first measures, air radon concentration exceeded International Commission Radiologica1 Protection (ICRP) normative (recommends intervention between 400 and 1000 Bq m(-3)). Therefore, the WWTP improved mechanical forced ventilation to lower occupational exposure. This measure allowed to increase the administrative controls, since the limitation of workers access to the plant changed from 2 h d(-1) (considering a maximum permissible dose of 20 mSv y(-1) averaged over 5 y) to 7 h d(-1). PMID:25971342

  7. Preliminary results of indoor radon survey in V4 countries.

    PubMed

    Muűllerová, M; Kozak, K; Kovács, T; Csordás, A; Grzadziel, D; Holý, K; Mazur, J; Moravcsík, A; Neznal, M; Neznal, M; Smetanová, I

    2014-07-01

    The measurements of radon activity concentration carried out in residential houses of V4 countries (Hungary, Poland and Slovakia) show that radon levels in these countries considerably exceed the world average. Therefore, the new radon data and statistical analysis are required from these four countries. Each partner chose a region in their own country, where radon concentration in residential buildings was expected to be higher. The results of the survey carried out in the period from March 2012 to May 2012 show that radon concentrations are <200 Bq m(-3) in ∼87% of cases. However, dwellings with radon concentration ∼800 Bq m(-3) were found in Poland and Slovakia. It was also found that the distribution of radon frequency follows that of houses according to the year of their construction.

  8. Assessment of test duration effect in indoor radon measurement by Monte Carlo simulations.

    PubMed

    Chen, Jing; Moir, Deborah

    2012-06-01

    To better understand the effect of various test durations on indoor radon measurement results in Canada, Monte Carlo simulations were performed for test durations of 1 month (30 d), 2 months (61 d), 3 months (91 d) and 6 months (183 d). For each of the specified test durations, a total of 1500 Monte Carlo simulations were performed. Each simulation was compared with the result of a 1-y measurement. On average, the radon concentration estimated from a 30-d test differed by about ±22 % from the value of a 1-y measurement. The difference reduced to about ±17 % for a 61-d test, ±14 % for a 91-d test and ±9 % for a half-year test. Health Canada's recommendation of a 3-month radon test performed during the heating season resulted in an estimated radon concentration, on average, ∼20 % higher than the value determined from a 1-y measurement. This ensures a conservative estimate of the annual average radon concentration, as there is some risk at any radon level. Therefore, to avoid an underestimation of radon exposure and to ensure appropriate levels of precision and accuracy are met, the results from this study suggest that a radon measurement duration of 3 months or longer during the heating season (from October through to April) is needed.

  9. A study of Monitoring and Mapping for Radon-Concentration Distribution in Gyeongju - 12201

    SciTech Connect

    Park, Chan Hee; Lee, Jung Min; Jang, So Young; Kim, Shin Jae; Moon, Joo Hyun

    2012-07-01

    Radon is one of the most important contributors to the radiation exposure in humans. This study measured the indoor radon concentrations at the 17 elementary school auditoriums that were sampled from those in the city of Gyeongju, Korea. The reason that an elementary school was selected as a measurement object is that many students and teachers stay for a long time in a day and it's easy to identify the characteristics of the auditorium building such as the essential building. The measurement shows that most of the indoor radon concentrations at the 17 elementary school auditoriums did not exceed 148 Bq/m{sup 3} that is the action level recommended by U.S. Environmental Protection Agency. This study measured the indoor radon concentrations at the elementary school auditoriums in Gyeongju. The measurements were analyzed according to the bedrock type and the time intervals per day. In this study, it was found that the indoor radon concentrations over off-duty hours were generally higher that those over on-duty hours, and the indoor radon concentration in the area whose bedrock is volcanic rock was higher than those in the area of the other types of bedrock. As mentioned above, attention has to be paid to an elementary school since many young students and teachers stay for more 6 hours a day at it. Hence, it is necessary to continuously monitor and properly manage the indoor radon concentrations in the elementary schools. (authors)

  10. Calibration of the Politrack® system based on CR39 solid-state nuclear track detectors for passive indoor radon concentration measurements.

    PubMed

    Kropat, G; Baechler, S; Bailat, C; Barazza, F; Bochud, F; Damet, J; Meyer, N; Palacios Gruson, M; Butterweck, G

    2015-11-01

    Swiss national requirements for measuring radon gas exposures demand a lower detection limit of 50 kBq h m(-3), representing the Swiss concentration average of 70 Bq m(-3) over a 1-month period. A solid-state nuclear track detector (SSNTD) system (Politrack, Mi.am s.r.l., Italy) has been acquired to fulfil these requirements. This work was aimed at the calibration of the Politrack system with traceability to international standards and the development of a procedure to check the stability of the system. A total of 275 SSNTDs was exposed to 11 different radon exposures in the radon chamber of the Secondary Calibration Laboratory at the Paul Scherrer Institute, Switzerland. The exposures ranged from 50 to 15000 kBq h m(-3). For each exposure of 20 detectors, 5 SSNTDs were used to monitor possible background exposures during transport and storage. The response curve and the calibration factor of the whole system were determined using a Monte Carlo fitting procedure. A device to produce CR39 samples with a reference number of tracks using a (241)Am source was developed for checking the long-term stability of the Politrack system. The characteristic limits for the detection of a possible system drift were determined following ISO Standard 11929.

  11. Effect of indoor-generated airborne particles on radon progeny dynamics.

    PubMed

    Trassierra, C Vargas; Stabile, L; Cardellini, F; Morawska, L; Buonanno, G

    2016-08-15

    In order to investigate the interaction between radon progeny and particles, an experimental campaign was carried out in a radon chamber at the Italian National Institute of Ionizing Radiation Metrology, quantifying the amount of attached and unattached radon daughters present in air, as well as the equilibrium factor in the presence of particles generated through indoor sources. A fixed radon concentration was maintained, while particles were generated using incense sticks, mosquito coils and gas combustion. Aerosols were characterized in terms of particle concentrations and size distributions. Simultaneously, radon concentration and attached/unattached potential alpha energy concentration in the air were continuously monitored by two different devices, based on alpha spectroscopy techniques. The presence of particles was found to affect the attached fraction of radon decay products, in such a way that the particles acted as a sink for radionuclides. In terms of sources which emit large particles (e.g. incense, mosquito coils), which greatly increase particle surface area concentrations, the Equilibrium Factor was found to double with respect to the background level before particle generation sessions. On the contrary, the radon decay product dynamics were not influenced by gas combustion processes, mainly due to the small surface area of the particles emitted. PMID:27131455

  12. Factors Affecting Radon Concentration in Houses

    NASA Astrophysics Data System (ADS)

    Al-Sharif, Abdel-Latif; Abdelrahman, Y. S.

    2001-03-01

    The dangers to the human health upon exposure to radon and its daughter products is the main motivation behind the vast number of studies performed to find the concentration of radon in our living environment, including our houses. The presence of radon and its daughter products in houses are due to various sources including building materials and the soil under the houses. Many factors affect radon concentration in our houses, the elevation above ground level,ventilation, building materials and room usage being among these factors. In our paper, we discuss the effect of elevation above ground level, room usage and ventilation on the Radon concentration in houses. The faculty residences of the Mu'tah University (Jordan) were chosen in our study. Our results showed that the concentration of radon decreases with elevation. Ventilation rate was also found to affect radon concentration, where low concentrations observed for areas with good ventilation.

  13. Dose estimation derived from the exposure to radon, thoron and their progeny in the indoor environment

    NASA Astrophysics Data System (ADS)

    Ramola, R. C.; Prasad, Mukesh; Kandari, Tushar; Pant, Preeti; Bossew, Peter; Mishra, Rosaline; Tokonami, S.

    2016-08-01

    The annual exposure to indoor radon, thoron and their progeny imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive measurements of indoor radon, thoron and their progeny concentrations that were carried out in Garhwal Himalaya with the aim of investigating significant health risk to the dwellers in the region. The measurements were performed using recently developed LR-115 detector based techniques. The experimentally determined values of radon, thoron and their progeny concentrations were used to estimate total annual inhalation dose and annual effective doses. The equilibrium factors for radon and thoron were also determined from the observed data. The estimated value of total annual inhalation dose was found to be 1.8 ± 0.7 mSv/y. The estimated values of the annual effective dose were found to be 1.2 ± 0.5 mSv/y and 0.5 ± 0.3 mSv/y, respectively. The estimated values of radiation doses suggest no important health risk due to exposure of radon, thoron and progeny in the study area. The contribution of indoor thoron and its progeny to total inhalation dose ranges between 13–52% with mean value of 30%. Thus thoron cannot be neglected when assessing radiation doses.

  14. Dose estimation derived from the exposure to radon, thoron and their progeny in the indoor environment.

    PubMed

    Ramola, R C; Prasad, Mukesh; Kandari, Tushar; Pant, Preeti; Bossew, Peter; Mishra, Rosaline; Tokonami, S

    2016-01-01

    The annual exposure to indoor radon, thoron and their progeny imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive measurements of indoor radon, thoron and their progeny concentrations that were carried out in Garhwal Himalaya with the aim of investigating significant health risk to the dwellers in the region. The measurements were performed using recently developed LR-115 detector based techniques. The experimentally determined values of radon, thoron and their progeny concentrations were used to estimate total annual inhalation dose and annual effective doses. The equilibrium factors for radon and thoron were also determined from the observed data. The estimated value of total annual inhalation dose was found to be 1.8 ± 0.7 mSv/y. The estimated values of the annual effective dose were found to be 1.2 ± 0.5 mSv/y and 0.5 ± 0.3 mSv/y, respectively. The estimated values of radiation doses suggest no important health risk due to exposure of radon, thoron and progeny in the study area. The contribution of indoor thoron and its progeny to total inhalation dose ranges between 13-52% with mean value of 30%. Thus thoron cannot be neglected when assessing radiation doses. PMID:27499492

  15. Dose estimation derived from the exposure to radon, thoron and their progeny in the indoor environment

    PubMed Central

    Ramola, R. C.; Prasad, Mukesh; Kandari, Tushar; Pant, Preeti; Bossew, Peter; Mishra, Rosaline; Tokonami, S.

    2016-01-01

    The annual exposure to indoor radon, thoron and their progeny imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive measurements of indoor radon, thoron and their progeny concentrations that were carried out in Garhwal Himalaya with the aim of investigating significant health risk to the dwellers in the region. The measurements were performed using recently developed LR-115 detector based techniques. The experimentally determined values of radon, thoron and their progeny concentrations were used to estimate total annual inhalation dose and annual effective doses. The equilibrium factors for radon and thoron were also determined from the observed data. The estimated value of total annual inhalation dose was found to be 1.8 ± 0.7 mSv/y. The estimated values of the annual effective dose were found to be 1.2 ± 0.5 mSv/y and 0.5 ± 0.3 mSv/y, respectively. The estimated values of radiation doses suggest no important health risk due to exposure of radon, thoron and progeny in the study area. The contribution of indoor thoron and its progeny to total inhalation dose ranges between 13–52% with mean value of 30%. Thus thoron cannot be neglected when assessing radiation doses. PMID:27499492

  16. Radon concentrations in different types of dwellings in Israel.

    PubMed

    Epstein, L; Koch, J; Riemer, T; Orion, I; Haquin, G

    2014-12-01

    The average radon concentration in Israeli dwellings was assessed by combining the results of a 2006 radon survey in single-family houses with the results of a 2011 radon survey in apartments of multistorey buildings. Both surveys were based on long-term measurements using CR-39 detectors. The survey in multistorey buildings was intended to assess the influence of recent practices in the local building industry on the radon concentrations. These practices include the use of building materials with higher concentrations of the natural radionuclides in the last 20 y than before, as well as the improvement in sealing techniques over that period. Another practice in place since the early 1990 s is the building of a shielded area in every apartment that is known as an RSS (residential secure space). The RSS is a room built from massive concrete walls, floor and ceiling that can be hermetically sealed and is intended to protect its residents from a missile attack. The influence of the above-mentioned features on radon concentrations was estimated by dividing the participating apartments into two groups: apartments in buildings >20 y, built using building materials with low concentrations of the natural radionuclides, regular sealing and without an RSS and apartments in buildings newer than 10 y, built using building materials with higher concentrations of the natural radionuclides, improved sealing and including an RSS. It was found that the average radon concentration in apartments in new buildings was significantly higher than in old buildings and the average radon concentration in single-family houses was significantly higher than in apartments in multistorey buildings. Doses due to indoor radon were estimated on the basis of the updated information included in the 2009 International Commission on Radiological Protection statement on radon.

  17. Indoor radon monitoring near an in situ leach mining site in D G Khan, Pakistan.

    PubMed

    Matiullah; Malik, Fariha; Rafique, Muhammad

    2012-12-01

    Indoor radon and its decay products are considered to be the second leading cause of lung cancer after cigarette smoking. This is why extensive radon surveys have been carried out in many countries of the world, including Pakistan. In this context, 25 spots were selected at workplaces in the vicinity of the uranium mining site in Dera Ghazi Khan District for indoor radon measurement. For this purpose, CR-39 based radon detectors were installed at head height and were exposed to indoor radon for 60 days. After retrieval, these detectors were etched in a 6 M solution of NaOH at the temperature of 80 °C for 16 h in order to make the alpha particle tracks visible. The observed track densities were related to the indoor radon concentration using a calibration factor of 2.7 tracks cm(-2) h(-1)/kBq m(-3). The measured indoor radon concentration ranged from ∼386 ±161 to 3028 ± 57 Bq m(-3) with an average value of 1508 ± 81 Bq m(-3) in the studied areas of Dera Ghazi Khan District. The mean annual effective dose ranged from 2.22 ± 0.93 to 17.44 ± 0.33 mSv yr(-1), with an average of 8.68 ± 0.47 mSv yr(-1). The effect of the seasonal correction factor (SCF) on the annual average radon concentration has also been considered. Results of the current study show that, for the majority of the workplaces studied, indoor radon levels exceed the action levels proposed by many world organisations.

  18. TESTING OF INDOOR RADON REDUCTION TECHNIQUES IN 19 MARYLAND HOUSES

    EPA Science Inventory

    The report gives results of testing of indoor radon reduction techniques in 19 existing houses in Maryland. The focus was on passive measures: various passive soil depressurization methods, where natural wind and temperature effects are utilized to develop suction in the system; ...

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

    SciTech Connect

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

    2000-03-01

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

  20. Evaluation on different sampling schemes for assessing indoor radon level in Hong Kong

    NASA Astrophysics Data System (ADS)

    Mui, K. W.; Wong, L. T.

    In order to maintain an acceptable indoor air quality (IAQ), policies, strategies and guidelines on achieving the required IAQ have been developed worldwide. In Hong Kong, the Environmental Protection Department (HKEPD) has launched an IAQ certification scheme to promote an acceptable IAQ in workplaces. For the practical radon measurement, an 8-h continuous monitoring is proposed for the assessment purpose. However, the uncertainties and measurement efforts associated with the method have not been detailed. In this study, the probable errors and measurement efforts in measuring the indoor radon concentration by three proposed sampling schemes of various sampling periods have been investigated. Scheme A is to obtain an average concentration over a sampling period in an occupied period; Scheme B is to obtain an average concentration in two sampling periods from two sessions of the occupied period; and for Scheme C, the average concentration in two structural sampling periods from two sessions of the occupied period. In particular, a 1-year measurement of indoor radon concentration in a typical office building has been used as basis to evaluate the probable errors between the long-term average and those obtained by the three measurement schemes. At a certain confidence level, the results show that the measurement time required for Schemes B and C could be reduced significantly, when compared with Scheme A using continuous monitoring. It is recommended to specify the measurement uncertainty and effort in future codes, and the sampling schemes could be considered in determining the practical strategies for radon measurement.

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

  2. Measurement of Radon in Indoor Air.

    ERIC Educational Resources Information Center

    Downey, Daniel M.; Simolunas, Glenn

    1988-01-01

    Describes a laboratory experiment to teach the principles of air sampling, gamma ray spectroscopy, nuclear decay, and radioactive equilibrium. Analyzes radon by carbon adsorption and gamma ray counting. Provides methodology and rate of decay equations. (MVL)

  3. Indoor radon levels in Cumberland County, PA

    SciTech Connect

    Cohen, B.L.; Nason, R.

    1987-01-01

    Measurements were made of radon levels in 165 randomly selected homes in Cumberland County, PA during Winter 1984-1985. The average and mean levels were found to be 9.1 +/- 0.7 pCi/L and 6.3 +/- 0.5 pCi/L, respectively, many times normally encountered levels. Average and mean radon levels are reported vs. various house characteristics. 4 references, 1 figure, 6 tables.

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

    PubMed

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

    2015-02-01

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

  5. Radon in indoor air of primary schools: determinant factors, their variability and effective dose.

    PubMed

    Madureira, Joana; Paciência, Inês; Rufo, João; Moreira, André; de Oliveira Fernandes, Eduardo; Pereira, Alcides

    2016-04-01

    Radon is a radioactive gas, abundant in granitic areas, such as in the city of Porto at the north-east of Portugal. This gas is a recognized carcinogenic agent, being appointed by the World Health Organization as the leading cause of lung cancer after smoking. The aim of this preliminary survey was to determine indoor radon concentrations in public primary schools, to analyse the main factors influencing their indoor concentration levels and to estimate the effective dose in students and teachers in primary schools. Radon concentrations were measured in 45 classrooms from 13 public primary schools located in Porto, using CR-39 passive radon detectors for about 2-month period. In all schools, radon concentrations ranged from 56 to 889 Bq/m(3) (mean = 197 Bq/m(3)). The results showed that the limit of 100 Bq/m(3) established by WHO IAQ guidelines was exceeded in 92 % of the measurements, as well as 8 % of the measurements exceeded the limit of 400 Bq/m(3) established by the national legislation. Moreover, the mean annual effective dose was calculated as 1.25 mSv/y (ranging between 0.58 and 3.07 mSv/y), which is below the action level (3-10 mSv). The considerable variability of radon concentration observed between and within floors indicates a need to monitor concentrations in several rooms for each floor. A single radon detector for each room can be used, provided that the measurement error is considerably lower than variability of radon concentration between rooms. The results of the present survey will provide useful baseline data for adopting safety measures and dealing effectively with radiation emergencies. In particular, radon remediation techniques should be used in buildings located in the highest radon risk areas of Portugal. The results obtained in the current study concerning radon levels and their variations will be useful to optimize the design of future research surveys.

  6. Radon in indoor air of primary schools: determinant factors, their variability and effective dose.

    PubMed

    Madureira, Joana; Paciência, Inês; Rufo, João; Moreira, André; de Oliveira Fernandes, Eduardo; Pereira, Alcides

    2016-04-01

    Radon is a radioactive gas, abundant in granitic areas, such as in the city of Porto at the north-east of Portugal. This gas is a recognized carcinogenic agent, being appointed by the World Health Organization as the leading cause of lung cancer after smoking. The aim of this preliminary survey was to determine indoor radon concentrations in public primary schools, to analyse the main factors influencing their indoor concentration levels and to estimate the effective dose in students and teachers in primary schools. Radon concentrations were measured in 45 classrooms from 13 public primary schools located in Porto, using CR-39 passive radon detectors for about 2-month period. In all schools, radon concentrations ranged from 56 to 889 Bq/m(3) (mean = 197 Bq/m(3)). The results showed that the limit of 100 Bq/m(3) established by WHO IAQ guidelines was exceeded in 92 % of the measurements, as well as 8 % of the measurements exceeded the limit of 400 Bq/m(3) established by the national legislation. Moreover, the mean annual effective dose was calculated as 1.25 mSv/y (ranging between 0.58 and 3.07 mSv/y), which is below the action level (3-10 mSv). The considerable variability of radon concentration observed between and within floors indicates a need to monitor concentrations in several rooms for each floor. A single radon detector for each room can be used, provided that the measurement error is considerably lower than variability of radon concentration between rooms. The results of the present survey will provide useful baseline data for adopting safety measures and dealing effectively with radiation emergencies. In particular, radon remediation techniques should be used in buildings located in the highest radon risk areas of Portugal. The results obtained in the current study concerning radon levels and their variations will be useful to optimize the design of future research surveys. PMID:26100326

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

  8. Log-normality of indoor radon data in the Walloon region of Belgium.

    PubMed

    Cinelli, Giorgia; Tondeur, François

    2015-05-01

    The deviations of the distribution of Belgian indoor radon data from the log-normal trend are examined. Simulated data are generated to provide a theoretical frame for understanding these deviations. It is shown that the 3-component structure of indoor radon (radon from subsoil, outdoor air and building materials) generates deviations in the low- and high-concentration tails, but this low-C trend can be almost completely compensated by the effect of measurement uncertainties and by possible small errors in background subtraction. The predicted low-C and high-C deviations are well observed in the Belgian data, when considering the global distribution of all data. The agreement with the log-normal model is improved when considering data organised in homogeneous geological groups. As the deviation from log-normality is often due to the low-C tail for which there is no interest, it is proposed to use the log-normal fit limited to the high-C half of the distribution. With this prescription, the vast majority of the geological groups of data are compatible with the log-normal model, the remaining deviations being mostly due to a few outliers, and rarely to a "fat tail". With very few exceptions, the log-normal modelling of the high-concentration part of indoor radon data is expected to give reasonable results, provided that the data are organised in homogeneous geological groups.

  9. AN OVERVIEW OF INDOOR RADON RISK REDUCTION IN THE UNITED STATES

    EPA Science Inventory

    Radon in the indoor environment is a recognized environmental hazard. The Environmental Protection Agency (EPA) has established several programs to develop, demonstrate, and transfer radon mitigation technology. Administration and management of these programs are shared by EPA's ...

  10. Radon concentration measurements in bituminous coal mines.

    PubMed

    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.

  11. A study of indoor radon levels in rural dwellings of Ezine (Canakkale, Turkey) using solid-state nuclear track detectors.

    PubMed

    Orgün, Y; Altinsoy, N; Sahin, S Y; Ataksor, B; Celebi, N

    2008-01-01

    Indoor radon activity level and radon effective dose (ED) rate have been carried out in the rural dwellings of Ezine (Canakkale) during the summer season using Radosys-2000, a complete set suitable to radon concentration measurements with CR-39 plastic alpha track detectors. The range of radon concentration varied between 9 and 300 Bq m(-3), with an average of 67.9 (39.9 SD) Bq m(-3). Assuming an indoor occupancy factor of 0.8 and 0.4 for the equilibrium factor of radon indoors, it has been found that the 222Rn ED rate in the dwellings studied ranges from 0.4 to 5.2 mSv y(-1), with an average value of 1.7 (1.0) mSv y(-1). There is a possibility that low radon concentrations exist indoors during the summer season in the study area because of relatively high ventilation rates in the dwellings. A winter survey will be needed for future estimation of the annual ED.

  12. An updated review of case-control studies of lung cancer and indoor radon-Is indoor radon the risk factor for lung cancer?

    PubMed

    Sheen, Seungsoo; Lee, Keu Sung; Chung, Wou Young; Nam, Saeil; Kang, Dae Ryong

    2016-01-01

    Lung cancer is a leading cause of cancer-related death in the world. Smoking is definitely the most important risk factor for lung cancer. Radon ((222)Rn) is a natural gas produced from radium ((226)Ra) in the decay series of uranium ((238)U). Radon exposure is the second most common cause of lung cancer and the first risk factor for lung cancer in never-smokers. Case-control studies have provided epidemiological evidence of the causative relationship between indoor radon exposure and lung cancer. Twenty-four case-control study papers were found by our search strategy from the PubMed database. Among them, seven studies showed that indoor radon has a statistically significant association with lung cancer. The studies performed in radon-prone areas showed a more positive association between radon and lung cancer. Reviewed papers had inconsistent results on the dose-response relationship between indoor radon and lung cancer risk. Further refined case-control studies will be required to evaluate the relationship between radon and lung cancer. Sufficient study sample size, proper interview methods, valid and precise indoor radon measurement, wide range of indoor radon, and appropriate control of confounders such as smoking status should be considered in further case-control studies.

  13. An updated review of case-control studies of lung cancer and indoor radon-Is indoor radon the risk factor for lung cancer?

    PubMed

    Sheen, Seungsoo; Lee, Keu Sung; Chung, Wou Young; Nam, Saeil; Kang, Dae Ryong

    2016-01-01

    Lung cancer is a leading cause of cancer-related death in the world. Smoking is definitely the most important risk factor for lung cancer. Radon ((222)Rn) is a natural gas produced from radium ((226)Ra) in the decay series of uranium ((238)U). Radon exposure is the second most common cause of lung cancer and the first risk factor for lung cancer in never-smokers. Case-control studies have provided epidemiological evidence of the causative relationship between indoor radon exposure and lung cancer. Twenty-four case-control study papers were found by our search strategy from the PubMed database. Among them, seven studies showed that indoor radon has a statistically significant association with lung cancer. The studies performed in radon-prone areas showed a more positive association between radon and lung cancer. Reviewed papers had inconsistent results on the dose-response relationship between indoor radon and lung cancer risk. Further refined case-control studies will be required to evaluate the relationship between radon and lung cancer. Sufficient study sample size, proper interview methods, valid and precise indoor radon measurement, wide range of indoor radon, and appropriate control of confounders such as smoking status should be considered in further case-control studies. PMID:26949535

  14. Diffusion of radon through concrete block walls: A significant source of indoor radon

    USGS Publications Warehouse

    Lively, R.S.; Goldberg, L.F.

    1999-01-01

    Basement modules located in southern Minnesota have been the site of continuous radon and environmental measurements during heating seasons since 1993. Concentrations of radon within the basement modules ranged from 70 Bq.m-3 to over 4000 Bq.m-3 between November to April during the three measurement periods. In the soil gas for the same times, concentrations of radon ranged between 25,000 and 70,000 Bq.m-3. Levels of radon within the basement modules changed by factors of five or more within 24 h, in concert with pressure gradients of 4 to 20 Pa that developed between the basement modules and their surroundings. Diffusion is identified as the principal method by which radon is transferred into and out of the basement modules, and appears to be relatively independent of insulating materials and vapour retarders. The variability of radon and correlations with differential pressure gradients may be related to air currents in the block walls and soil that interrupt radon diffusing inward. This yields a net decrease of radon in the basement modules by decay and outward diffusion. Levels of radon within the basement modules increase when the pressure differential is zero and air flow ceases, allowing diffusion gradients to be re-established. Radon levels in both the soil and the basement modules then increase until an equilibrium is achieved.

  15. Dealing with the increased radon concentration in thermally retrofitted buildings.

    PubMed

    Jiránek, M; Kačmaříková, V

    2014-07-01

    The influence of energy-saving measures on indoor radon concentration has been studied on the basis of a family house made of clinker concrete wall panels containing from 1000 up to 4000 Bq kg(-1) of 226Ra. Thermal retrofitting based on installing external thermal insulation composite system on the building envelope and replacing existing windows by new ones decreased the annual energy need for heating 2.8 times, but also reduced the ventilation rate to values<0.1 h(-1). As a consequence, the 1-y average indoor radon concentration values increased 3.4 times from 337 to 1117 Bq m(-3). The additional risk of lung cancer in the thermally retrofitted house increased to a value that is 125 % higher than before conversion. Methods for dealing with this enhanced risk by increasing the ventilation rate are discussed. Recovery of investments and the energy consequences of increased ventilation are studied in a long-term perspective.

  16. Exposure to indoor radon and natural gamma radiation in some workplaces at Algiers, Algeria.

    PubMed

    Aït Ziane, M; Lounis-Mokrani, Z; Allab, M

    2014-07-01

    Radon activity concentrations have been measured in 34 workplaces throughout Algiers nuclear research centre, in Algeria, during some periods between March 2007 and June 2013 using Electret ion chambers, nuclear tracks detectors and an AlphaGuard system. The indoor radon levels range from 2 to 628 Bq m(-3) with an average indoor concentration equals to 92 Bq m(-3), whereas the estimated outdoor radon concentrations range from 2 to 14 Bq m(-3) with an average value of 6 Bq m(-3). This study also focused on parameters affecting radon concentration levels such as floor number, ventilation and atmospheric parameters. Furthermore, the mean gamma rates have been measured in the different investigated locations and have been found to be varying between 33 and 3300 nSv h(-1). The annual effective dose for workers calculated using the appropriate equilibrium and occupancy factors is lower than the value recommended by International Commission on Radiological Protection in its Publication 103. PMID:24711531

  17. Indoor and outdoor radon levels and its diurnal variations in Botswana

    NASA Astrophysics Data System (ADS)

    Murty, V. R. K.; King, J. G.; Karunakara, N.; Raju, V. C. C.

    2010-07-01

    Studies on radon monitoring are essential for countries actively involved in mining activities. Since large-scale mining activities have the potential to enhance the background radiation levels, a detailed study on indoor and outdoor radon levels, its diurnal variation with temperature, pressure and humidity for Botswana is initiated. The study is important because such studies for Botswana are non-existent and the database on indoor and outdoor 222Rn concentration and the resulting inhalation dose to the population of the region is not available. Measurements were carried out using the AlphaGuard (Genitron,Germany) Professional Radon Monitor. The concentration of 226Ra in soil was also measured by gamma spectrometry using a 41% relative efficiency n-type HPGe detector (Canberra, USA). Initial results show that the indoor 222Rn concentration vary in the range 3.0-93.0 Bq m -3 with a mean of 24.5 Bq m -3. Diurnal variation studies show that the concentration is higher in the early morning hours and lower in the early afternoon hours. All the results are presented and discussed in detail in this paper.

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

    PubMed

    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.

  19. Systematic indoor radon and gamma-ray measurements in Slovenian schools

    SciTech Connect

    Vaupotic, J.; Sikovec, M.; Kobal, I.

    2000-05-01

    During the winter months of 1992/93 and 1993/94, instantaneous indoor radon concentrations and gamma dose rates were measured in 890 schools in Slovenia attended in total by about 280,000 pupils. Under closed conditions, the room to be surveyed was closed for more than 12 h prior to sampling, the air was sampled into alpha scintillation cells with a volume of 700 cm{sup 3}, and alpha activity was measured. An arithmetic mean of 168 Bq m{sup {minus}3} and a geometric mean of 82 Bq m{sup {minus}3} were obtained. In 67% of schools, indoor radon concentrations were below 100 Bq m{sup {minus}3}, and in 8.7% (77 schools with about 16,000 pupils) they exceeded 400 Bq m{sup {minus}3}, which is the proposed Slovene action level. In the majority of cases, radon concentrations were high due to the geological characteristics of the ground. Approximately 70% of schools with high radon levels were found in the Karst region. Gamma dose rates were measured using a portable scintillation counter. An arithmetic mean of 102 nGy h{sup {minus}1} and a geometric mean of 95 nGy h{sup {minus}1} were obtained. No extraordinarily high values were recorded.

  20. Ground and indoor radon measurements in a geothermal area

    NASA Astrophysics Data System (ADS)

    Seyis, Cemil; İnan, Sedat; Streil, Thomas

    2010-10-01

    Geothermally active sites compared to a relatively passive site (no geothermal activity) contain much higher radon in the soil. As expected, the maximum soil radon content is at or near the major fracture zone where hot water emanates to the surface. Thus, buildings in geothermal sites nearby or at top of cracks that facilitate hot-water transfer to the surface may be extremely dangerous in terms of high radon concentrations and this situation may pose a big threat for the inhabitants. Controlled aeration of such high-risk buildings must be carefully and continuously conducted.

  1. Indoor radon periodicities and their physical constraints: a study in the Coimbra region (Central Portugal).

    PubMed

    Neves, L J P F; Barbosa, S M; Pereira, A J S C

    2009-10-01

    Indoor radon activities were measured during a period of 6 months, as well as several physical environmental variables (temperature, pressure, humidity and rainfall). The location was a small room at an administrative building of the University of Coimbra, usually undisturbed by human activities and situated over bedrock of low-uranium Triassic red sandstones. A low average activity of radon was observed (36 Bq m(-3)), however showing a very well marked daily periodicity (10+/-5 Bq m(-3)), with maximum values occurring more frequently between 9 and 10 a.m. Daily variations are shown to have no relation with earth tides, and their amplitudes exhibit a significant correlation with outdoor temperature; no dependence on barometric pressure was found. Rainfall disturbs the observed daily radon cycles through a strong reduction of their amplitude, but has no effect on the long-term variability of the gas concentration. PMID:19632749

  2. Indoor radon periodicities and their physical constraints: a study in the Coimbra region (Central Portugal).

    PubMed

    Neves, L J P F; Barbosa, S M; Pereira, A J S C

    2009-10-01

    Indoor radon activities were measured during a period of 6 months, as well as several physical environmental variables (temperature, pressure, humidity and rainfall). The location was a small room at an administrative building of the University of Coimbra, usually undisturbed by human activities and situated over bedrock of low-uranium Triassic red sandstones. A low average activity of radon was observed (36 Bq m(-3)), however showing a very well marked daily periodicity (10+/-5 Bq m(-3)), with maximum values occurring more frequently between 9 and 10 a.m. Daily variations are shown to have no relation with earth tides, and their amplitudes exhibit a significant correlation with outdoor temperature; no dependence on barometric pressure was found. Rainfall disturbs the observed daily radon cycles through a strong reduction of their amplitude, but has no effect on the long-term variability of the gas concentration.

  3. Air conditioning impact on the dynamics of radon and its daughters concentration.

    PubMed

    Kozak, Krzysztof; Grządziel, Dominik; Połednik, Bernard; Mazur, Jadwiga; Dudzińska, Marzenna R; Mroczek, Mariusz

    2014-12-01

    Radon and its decay products are harmful pollutants present in indoor air and are responsible for the majority of the effective dose due to ionising radiation that people are naturally exposed to. The paper presents the results of the series of measurements of radon and its progeny (in unattached and attached fractions) as well as indoor air parameters: temperature, relative humidity, number and mass concentrations of fine aerosol particles. The measurements were carried out in the auditorium (lecture hall), which is an indoor air quality laboratory, in controlled conditions during two periods of time: when air conditioning (AC) was switched off (unoccupied auditorium) and when it was switched on (auditorium in normal use). The significant influence of AC and of students' presence on the dynamics of radon and its progeny was confirmed. A decrease in the mean value of radon and its attached progeny was found when AC was working. The mean value of radon equilibrium factor F was also lower when AC was working (0.49) than when it was off (0.61). The linear correlations were found between attached radon progeny concentration and particle number and mass concentration only when the AC was switched off. This research is being conducted with the aim to study the variability of radon equilibrium factor F which is essential to determine the effective dose due to radon and its progeny inhalation.

  4. Air conditioning impact on the dynamics of radon and its daughters concentration.

    PubMed

    Kozak, Krzysztof; Grządziel, Dominik; Połednik, Bernard; Mazur, Jadwiga; Dudzińska, Marzenna R; Mroczek, Mariusz

    2014-12-01

    Radon and its decay products are harmful pollutants present in indoor air and are responsible for the majority of the effective dose due to ionising radiation that people are naturally exposed to. The paper presents the results of the series of measurements of radon and its progeny (in unattached and attached fractions) as well as indoor air parameters: temperature, relative humidity, number and mass concentrations of fine aerosol particles. The measurements were carried out in the auditorium (lecture hall), which is an indoor air quality laboratory, in controlled conditions during two periods of time: when air conditioning (AC) was switched off (unoccupied auditorium) and when it was switched on (auditorium in normal use). The significant influence of AC and of students' presence on the dynamics of radon and its progeny was confirmed. A decrease in the mean value of radon and its attached progeny was found when AC was working. The mean value of radon equilibrium factor F was also lower when AC was working (0.49) than when it was off (0.61). The linear correlations were found between attached radon progeny concentration and particle number and mass concentration only when the AC was switched off. This research is being conducted with the aim to study the variability of radon equilibrium factor F which is essential to determine the effective dose due to radon and its progeny inhalation. PMID:24375376

  5. A representative survey of indoor radon in the sixteen regions in Mexico City.

    PubMed

    Espinosa, G; Gammage, R B

    2003-01-01

    Mexico City, also called Federal District, covers an area of 1504 km(2), and has more than 8 million inhabitants. It is located more than 2200 m above sea level in a zone of high seismic activity, and founded on an ancient lake. At present it is one of the most crowded and contaminated cities in the world, with thermal inversions. Chemical contaminants and aerosol particles in the environmental air are high most of the year. Due to these geological, environmental and socioeconomic conditions, Federal District presents very peculiar characteristics, which are important for understanding the distribution and measurements of indoor radon concentration. In this work the results of 3 year (1998-2000) measurements of indoor radon levels in the Federal District are presented. For the detector distribution and measurements, the actual political administrative divisions of the Federal District, consisting of 16 very well defined zones, was used. Nuclear track detection methodology was selected for the measurement, with a passive device close-end-cup system with CR-39 (Lantrack) polycarbonate as the detection material, with one step chemical etching, following a very well established protocol developed at the Instituto de Física, UNAM. Calibration was carried out at the Oak Ridge National Laboratory, and verification at the Instituto de Física chamber. The results show that the arithmetical mean values of the indoor radon concentration for each region of the Federal District follow a non-homogenous distribution.

  6. Modeled atmospheric radon concentrations from uranium mines

    SciTech Connect

    Droppo, J.G.

    1985-04-01

    Uranium mining and milling operations result in the release of radon from numerous sources of various types and strengths. The US Environmental Protection Agency (EPA) under the Clean Air Act, is assessing the health impact of air emissions of radon from underground uranium mines. In this case, the radon emissions may impact workers and residents in the mine vicinity. To aid in this assessment, the EPA needs to know how mine releases can affect the radon concentrations at populated locations. To obtain this type of information, Pacific Northwest Laboratory used the radon emissions, release characteristics and local meterological conditions for a number of mines to model incremental radon concentrations. Long-term, average, incremental radon concentrations were computed based on the best available information on release rates, plume rise parameters, number and locations of vents, and local dispersion climatology. Calculations are made for a model mine, individual mines, and multiple mines. Our approach was to start with a general case and then consider specific cases for comparison. A model underground uranium mine was used to provide definition of the order of magnitude of typical impacts. Then computations were made for specific mines using the best mine-specific information available for each mine. These case study results are expressed as predicted incremental radon concentration contours plotted on maps with local population data from a previous study. Finally, the effect of possible overlap of radon releases from nearby mines was studied by calculating cumulative radon concentrations for multiple mines in a region with many mines. The dispersion model, modeling assumptions, data sources, computational procedures, and results are documented in this report. 7 refs., 27 figs., 18 tabs.

  7. Variation of annual effective dose due to radon level in indoor air in Marwar region of Rajasthan, India

    NASA Astrophysics Data System (ADS)

    Rani, Asha; Mittal, Sudhir; Mehra, Rohit

    2015-08-01

    In the present work, indoor radon and thoron measurements have been carried out from different locations of Jodhpur and Nagaur districts of Northern Rajasthan, India using RAD7, a solid state alpha detector. The radon and thoron concentration in indoor air varies from 8.75 to 61.25 Bq m-3 and 32.7 to 147.2 Bq m-3 with the mean value of 32 and 73 Bq m-3 respectively. The observed indoor radon concentration values are well below the action level recommended by International Commission on Radiological Protection (200-300 Bq m-3) and Environmental Protection Agency (148 Bq m-3). The survey reveals that the thoron concentration values in the indoor air are well within the International Commission on Radiological Protection (2005). The calculated total annual effective dose due to radon level in indoor air varies from 0.22 to 1.54 mSv y-1 with the mean value of 0.81 mSv y-1 which is less than even the lower limit of action level 3-10 mSv y-1 recommended by International Commission on Radiological Protection (2005).

  8. Variation of annual effective dose due to radon level in indoor air in Marwar region of Rajasthan, India

    SciTech Connect

    Rani, Asha; Mittal, Sudhir; Mehra, Rohit

    2015-08-28

    In the present work, indoor radon and thoron measurements have been carried out from different locations of Jodhpur and Nagaur districts of Northern Rajasthan, India using RAD7, a solid state alpha detector. The radon and thoron concentration in indoor air varies from 8.75 to 61.25 Bq m{sup −3} and 32.7 to 147.2 Bq m{sup −3} with the mean value of 32 and 73 Bq m{sup −3} respectively. The observed indoor radon concentration values are well below the action level recommended by International Commission on Radiological Protection (200-300 Bq m{sup −3}) and Environmental Protection Agency (148 Bq m{sup −3}). The survey reveals that the thoron concentration values in the indoor air are well within the International Commission on Radiological Protection (2005). The calculated total annual effective dose due to radon level in indoor air varies from 0.22 to 1.54 mSv y{sup −1} with the mean value of 0.81 mSv y{sup −1} which is less than even the lower limit of action level 3-10 mSv y{sup −1} recommended by International Commission on Radiological Protection (2005)

  9. Preliminary results from an indoor radon thoron survey in Hungary.

    PubMed

    Szeiler, G; Somlai, J; Ishikawa, T; Omori, Y; Mishra, R; Sapra, B K; Mayya, Y S; Tokonami, S; Csordás, A; Kovács, T

    2012-11-01

    More than half of the radiation dose of natural origin comes from radon. However, according to some surveys in certain cases, the radiation dose originating from thoron may be considerable. Among the factors disturbing the measurement of radon, the presence of thoron may also influence the measured radon value, making the estimated radiation exposure imprecise. Thoron has previously been surveyed, mainly in Asia; however, recent surveys for some European locations have found that significant thoron concentrations also need to be considered. In this survey, several types of commercially available SSNTDs (solid-state nuclear track detectors) capable of measuring both radon and thoron were placed at the same time in 73 houses and 7 workplaces in Hungary with 3-month exposition periods. In order to measure thoron, the distance of the detector sets was fixed as 15-20 cm from the walls. The radon concentration was measured with five types of SSNTDs: NRPB, NRPB SSI, Raduet, DTPS and DRPS. The first four types had relatively good accordance (within ± 10 %), but the results of the DRPS detectors were considerably lower when compared with other detectors for radon concentrations over 100 Bq m(-3). The thoron averages were provided by two different types of detectors: Raduet and DTPS. The difference between their average results was more than 30 % and was six times the maximum values. Therefore, the thoron measurement results were judged to be erroneous, and their measurement protocol should be clearly established for future work.

  10. Measurement and apportionment of radon source terms for modeling indoor environments

    SciTech Connect

    Harley, N.H.

    1990-01-01

    This research has two main goals; (1) to quantify mechanisms for radon entry into homes of different types and to determine the fraction of indoor radon attributable to each source and (2) to model and calculate the dose (and therefore alpha particle fluence) to cells in the human and animal tracheobronchial tree that is pertinent to induction of bronchogenic carcinoma from inhaled radon daughters.

  11. Seasonal changes in radon concentrations in buildings in the region of northeastern Poland.

    PubMed

    Karpińska, Maria; Mnich, Zenon; Kapała, Jacek

    2004-01-01

    In this study, seasonal observations of radon concentration changes inside buildings carried out in the northeastern region of Poland is presented. One-year measurements of radon concentrations were performed in chosen buildings. The integral method of Cr-39 trace detectors in diffusive chambers was used. Mean values of radon concentrations were determined in monthly, 2-, 3-, 6-month, and annual observations. The fraction of a mean annual concentration of the value obtained in a shorter observation was calculated. Monthly concentration values were from about 0.2 to 14.9 of the annual mean. All buildings revealed seasonal fluctuation of radon concentration. Negative correlation of indoor radon concentration in the buildings and the mean temperature outside was observed in most examined buildings. The lowest coefficient range, determining which part of the annual mean value would be obtained in the 6-month observation, was gained for exposure begun in April or October.

  12. Indoor radon measurements in the granodiorite area of Bergama (Pergamon)-Kozak, Turkey.

    PubMed

    Karadeniz, Ozlem; Yaprak, Günseli; Akal, Cüneyt; Emen, Ipek

    2012-04-01

    Indoor radon levels in 20 dwellings of rural areas at the Kozak-Bergama (Pergamon) granodiorite area in Turkey were measured by the alpha track etch integrated method. These dwellings were monitored for eight successive months. Results show that the radon levels varied widely in the area ranging from 11±1 to 727±11 Bq m(-3) and the geometric mean was found to be 63 Bq m(-3) with a geometric standard deviation of 2 Bq m(-3). A log-normal distribution of the radon concentration was obtained for the studied area. Estimated annual effective doses due to the indoor radon ranged from 0.27 to 18.34 mSv y(-1) with a mean value of 1.95 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 Radiation Protection. All dosimetric calculations were performed based on the guidance of the UNSCEAR 2000 report.

  13. Long-term radon concentrations estimated from 210Po embedded in glass

    USGS Publications Warehouse

    Lively, R.S.; Steck, D.J.

    1993-01-01

    Measured surface-alpha activity on glass exposed in radon chambers and houses has a linear correlation to the integrated radon exposure. Experimental results in chambers and houses have been obtained on glass exposed to radon concentrations between 100 Bq m-3 and 9 MBq m-3 for periods of a few days to several years. Theoretical calculations support the experimental results through a model that predicts the fractions of airborne activity that deposit and become embedded or adsorbed. The combination of measured activity and calculated embedded fraction for a given deposition environment can be applied to most indoor areas and produces a better estimate for lifetime radon exposure than estimates based on short-term indoor radon measurements.

  14. Risk of leukaemia or cancer in the central nervous system among children living in an area with high indoor radon concentrations: results from a cohort study in Norway

    PubMed Central

    Del Risco Kollerud, R; Blaasaas, K G; Claussen, B

    2014-01-01

    Background: Over the past few years, there has been growing interest in assessing the relationship between exposure to radon at home and the risk of childhood cancer. Previous studies have produced conflicting results, probably because of limitations assessing radon exposure, too few cancer cases and poorly documented health statistics. Methods: We used a cohort approach of 0–15-year-old children to examine whether residential radon exposure was associated with childhood leukaemia and cancer in the central nervous system in the Oslo region. The study was based on Norwegian population registers and identified cancer cases from The Cancer Registry of Norway. The residence of every child was geo-coded and assigned a radon exposure. Results: In all, 712 674 children were followed from 1967 to 2009 from birth to date of cancer diagnosis, death, emigration or 15 years of age. A total of 864 cancer cases were identified, 437 children got leukaemia and 427 got cancer in the central nervous system. Conclusions or interpretation: No association was found for childhood leukaemia. An elevated nonsignificant risk for cancer in the central nervous system was observed. This association should be interpreted with caution owing to the crude exposure assessment and possibilities of confounding. PMID:25117818

  15. Lung Cancer Attributable to Indoor Radon Exposure in France: Impact of the Risk Models and Uncertainty Analysis

    PubMed Central

    Catelinois, Olivier; Rogel, Agnès; Laurier, Dominique; Billon, Solenne; Hemon, Denis; Verger, Pierre; Tirmarche, Margot

    2006-01-01

    Objective The inhalation of radon, a well-established human carcinogen, is the principal—and omnipresent—source of radioactivity exposure for the general population of most countries. Scientists have thus sought to assess the lung cancer risk associated with indoor radon. Our aim here is to assess this risk in France, using all available epidemiologic results and performing an uncertainty analysis. Methods We examined the exposure–response relations derived from cohorts of miners and from joint analyses of residential case-control studies and considered the interaction between radon and tobacco. The exposure data come from measurement campaigns conducted since the beginning of the 1980s by the Institute for Radiation Protection and Nuclear Safety and the Directorate-General of Health in France. We quantified the uncertainties associated with risk coefficients and exposures and calculated their impact on risk estimates. Results The estimated number of lung cancer deaths attributable to indoor radon exposure ranges from 543 [90% uncertainty interval (UI), 75–1,097] to 3,108 (90% UI, 2,996–3,221), depending on the model considered. This calculation suggests that from 2.2% (90% UI, 0.3–4.4) to 12.4% (90% UI, 11.9–12.8) of these deaths in France may be attributable to indoor radon. Discussion In this original work we used different exposure–response relations from several epidemiologic studies and found that regardless of the relation chosen, the number of lung cancer deaths attributable to indoor radon appears relatively stable. Smokers can reduce their risk not only by reducing their indoor radon concentration but also by giving up smoking. PMID:16966089

  16. Indoor radon monitoring in Northern Iran using passive and active measurements.

    PubMed

    Hadad, Kamal; Doulatdar, R; Mehdizadeh, S

    2007-01-01

    In this work we present the results of a 2-year survey of indoor radon variations in four cities of Lahijan, Ardabil, Sar-Ein and Namin in North and Northwest Iran. We used both passive and active measurements by solid state nuclear track detectors (SSNTDs) with CR-39 polycarbonate and PRASSI Portable radon Gas Surveyor. A total of 1124 samplers in Lahijan, Ardabil, Sar-Ein and Namin were installed. Sampling frequency was seasonal and sampling locations were randomly chosen based on dwelling structures, floors, geological formations, elevation and temperature variation parameters. For quality assurance, 281 active measurements and double sampling were carried out. Based on our results and the results of previous surveys, Ardabil and Lahijan have the second and third highest radon concentration in Iran, respectively (Ramsar is first). The average radon concentration during the year in Lahijan, Ardabil, Sar-Ein and Namin were 163, 240, 160 and 144 Bq/m(3) with medians of 160, 168, 124 and 133 Bq/m(3), respectively. These concentrations give rise to annual effective doses of 3.43 mSv/y for Lahijan and 5.00 mSv/y for Ardabil. The maximum recorded concentration was 2386 Bq/m(3) during winter in Ardabil and the minimum concentration was 55 Bq/m(3) during spring in Lahijan. Relationships between radon concentration and building materials and room ventilation were also studied. The dosimetry calculations showed that these four cities could be categorized as average natural radiation zones. The correlation coefficients relating warm and cold season radon variation data were obtained.

  17. Indoor 222Rn concentration measurements in some buildings of Hebron province during the winter season of the year 2000.

    PubMed

    Leghrouz, Amin A; Abu-Samreh, Mohammad M; Awawdah, Karam M; Abu-Taha, Mohammed I; Saleh, Abdelkarim M; Kitaneh, Rushdi M; Darwish, Saquer M

    2007-01-01

    In this study, we report on the indoor radon concentration levels in a number of locations scattered in the Hebron province, Palestine. The measurements were performed during the winter season of the year 1999/2000 using the CR-39 detectors. The radon concentration levels were found to vary from 23 to 580 Bq m(-3). The arithmetic average of the obtained radon concentration levels was found to be 91 Bq m(-3). It was found that most of the radon concentration levels in houses and school rooms are below the low reference levels limits. Most of the high-radon concentration levels were found in unpainted storage rooms.

  18. Nanoaerosols Including Radon Decay Products in Outdoor and Indoor Air at a Suburban Site

    PubMed Central

    Smerajec, Mateja; Vaupotič, Janja

    2012-01-01

    Nanoaerosols have been monitored inside a kitchen and in the courtyard of a suburban farmhouse. Total number concentration and number size distribution (5–1000 nm) of general aerosol particles, as measured with a Grimm Aerosol SMPS+C 5.400 instrument outdoors, were mainly influenced by solar radiation and use of farming equipment, while, indoors, they were drastically changed by human activity in the kitchen. In contrast, activity concentrations of the short-lived radon decay products 218Po, 214Pb, and 214Bi, both those attached to aerosol particles and those not attached, measured with a Sarad EQF3020-2 device, did not appear to be dependent on these activities, except on opening and closing of the kitchen window. Neither did a large increase in concentration of aerosol particles smaller than 10 or 20 nm, with which the unattached radon products are associated, augment the fraction of the unattached decay products significantly. PMID:22523488

  19. Concentrations of radon and its daughter products in and around Bangalore city.

    PubMed

    Ningappa, C; Sannappa, J; Chandrashekara, M S; Paramesh, L

    2008-01-01

    Indoor radon and its progeny levels were measured during 2005-06 in Bangalore rural district and in Bangalore City by using Solid State Nuclear Track Detector (SSNTD)-based twin cup dosemeters, and the activity of radium present in soils and rocks was measured by using HPGe detector. Fifty dwellings of different types were chosen for the measurement. The dosimeters containing the detector (LR-115 Type II Film) used in each house were fixed 2 m above the floor. After an exposure time of 90 days, films were etched to reveal tracks. From the track density, the concentrations of radon were evaluated. The value of radon concentration in the indoor air near granite quarries varies from 55 to 300 Bq.m(-3) with a median of 155 Bq.m(-3) and its progeny varies from 0.24 to 19.6 mWL with a median of 8.4 mWL. In Bangalore City, the concentration of radon varies from 18.4 to 110 Bq.m(-3) with a median of 45 Bq.m(-3) and its progeny varies from 1.62 to 11.24 mWL with a median of 4.15 mWL. Higher concentrations of radon and its progeny were observed in granite quarries compared with Bangalore City. The main reason for the higher indoor radon and its progeny concentration is due to the mining activity and the types of the bedrock. The concentration of radon mainly depends on the activity of radium present in soils and rocks and the types of building materials used. The activity of radium varies in granitic regions of Bangalore rural district from 42.0 to 163.6 Bq.kg(-1) with a median of 112.8 Bq.kg(-1). The concentrations of indoor radon and its daughter products and equivalent effective dose are discussed.

  20. Radon concentrations in spa water taken from hot and cold springs in Taiwan.

    PubMed

    Weng, P S; Lin, C L

    1995-05-01

    Spa water samples taken from hot and cold springs throughout Taiwan were analyzed for waterborne radon concentrations using electret ion chambers. The highest radon concentration was detected at Yangmingshan National Park, where it is closed to the action level of 11.0 kBq m-3. Next comes a sea-water hot spring at Green Isle on the east coast of Taiwan. The spa water used by the nearby inhabitants may increase the indoor radon concentration by a factor of two in extreme cases.

  1. Seasonally enhanced indoor radon in karst regions of the southern Applachians

    SciTech Connect

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

    1992-01-01

    The ratios of winter/summer indoor radon levels for houses in different regions of the southern Appalachians are characterized by individual log-normal distributions with geometric means both above and below unity. In some counties and cities, subpopulations of houses have unusually exaggerated winter/summer ratios of indoor radon, as well as high indoor radon levels, during periods of either warm or cool weather. It is proposed that in many instances, houses are communicating with larger than normal underground reservoirs of radon-bearing air in hilly karst terrains; differences between the outdoor and underground air temperatures are believed to provide the aerostatic pressure differences for seasonally directed underground transport and subsequently elevated indoor radon.

  2. Seasonally enhanced indoor radon in karst regions of the southern Applachians

    SciTech Connect

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

    1992-06-01

    The ratios of winter/summer indoor radon levels for houses in different regions of the southern Appalachians are characterized by individual log-normal distributions with geometric means both above and below unity. In some counties and cities, subpopulations of houses have unusually exaggerated winter/summer ratios of indoor radon, as well as high indoor radon levels, during periods of either warm or cool weather. It is proposed that in many instances, houses are communicating with larger than normal underground reservoirs of radon-bearing air in hilly karst terrains; differences between the outdoor and underground air temperatures are believed to provide the aerostatic pressure differences for seasonally directed underground transport and subsequently elevated indoor radon.

  3. Review of low-energy construction, air tightness, ventilation strategies and indoor radon: results from Finnish houses and apartments.

    PubMed

    Arvela, H; Holmgren, O; Reisbacka, H; Vinha, J

    2014-12-01

    Low-energy and passive house construction practices are characterised by increased insulation, high air tightness of the building shell and controlled mechanical ventilation with heat recovery. As a result of the interaction of mechanical ventilation and high air tightness, the pressure difference in a building can be markedly enhanced. This may lead to elevated indoor radon levels. Minor leakages in the foundation can affect the radon concentration, even in the case where such leaks do not markedly reduce the total air tightness. The potential for high pressures to affect indoor radon concentrations markedly increases when the air tightness ACH50, i.e. the air change per hour induced by a pressure difference of 50 Pa, is <1.0 h(-1). Pressure differences in Finnish low-rise residential houses having mechanical supply and exhaust ventilation with heat recovery (MSEV) are typically 2-3 Pa, clearly lower than the values of 5-9 Pa in houses with only mechanical exhaust ventilation (MEV). In MSEV houses, radon concentrations are typically 30% lower than in MEV houses. In new MSEV houses with an ACH50 of 0.6 h(-1), the limit for passive construction, the analytical estimates predict an increase of 100% in the radon concentration compared with older houses with an ACH50 of 4.0 h(-1). This poses a challenge for efficient radon prevention in new construction. Radon concentrations are typically 30% lower in houses with two storeys compared with only one storey. The introduction of an MSEV ventilation strategy in typically very airtight apartments has markedly reduced pressure differences and radon concentrations.

  4. Measurement of Indoor Radon, Thoron in Dwelling of Delhi, India Using Double Dosimeter Cups with SSNTDS

    NASA Astrophysics Data System (ADS)

    Sharma, Anil; Mahur, Ajay Kumar; Sonkawade, R. G.; Sharma, A. C.

    In present study, Solid State Nuclear Track Detectors (SSNTDS) based twin chamber dosimeter cups were used for estimating Radon (222Rn) and Thoron (220Rn) gas concentration levels in the environmental air of normal background radiation area in thirty one dwellings of Dwarka city of New Delhi, India which were constructed by bricks, cement and concrete. This survey is the very first one carried out in this city and constitutes and preliminary survey to check the methodology and to have a first estimation of the indoor radon impact on Dwarka inhabitants. LR-115 type-II, films were used as detector. In the studied dwellings Radon concentration levels were found to vary from 4.4 ± 1.6 to 29.8 ± 3.8 Bqm-3 whereas thoron concentrations is found to vary from 2.8 ± 0.5 to 13.6 ± 1.7 Bqm-3. The annual effective dose from radon were found to vary from 0.12 to 0.86 mSv whereas from thoron found to vary from 0.01 to 0.07 mSv.

  5. Distance to faults as a proxy for radon gas concentration in dwellings.

    PubMed

    Drolet, Jean-Philippe; Martel, Richard

    2016-02-01

    This research was done to demonstrate the usefulness of the local structural geology characteristics to predict indoor radon concentrations. The presence of geologic faults near dwellings increases the vulnerability of the dwellings to elevated indoor radon by providing favorable pathways from the source uranium-rich bedrock units to the surface. Kruskal-Wallis one-way analyses of variance by ranks were used to determine the distance where faults have statistically significant influence on indoor radon concentrations. The great-circle distance between the 640 spatially referenced basement radon concentration measurements and the nearest fault was calculated using the Haversine formula and the spherical law of cosines. It was shown that dwellings located less than 150 m from a major fault had a higher radon potential. The 150 m threshold was determined using Kruskal-Wallis ANOVA on: (1) all the basement radon measurements dataset and; (2) the basement radon measurements located on uranium-rich bedrock units only. The results indicated that 22.8% of the dwellings located less than 150 m from a fault exceeded the Canadian radon guideline of 200 Bq/m(3) when using all the basement radon measurements dataset. This percentage fell to 15.2% for the dwellings located between 150 m and 700 m from a fault. When using only the basement radon measurements located on uranium-rich bedrock units, these percentages were 30.7% (0-150 m) and 17.5% (150 m-700 m). The assessment and management of risk can be improved where structural geology characteristics base maps are available by using this proxy indicator. PMID:26630035

  6. Distance to faults as a proxy for radon gas concentration in dwellings.

    PubMed

    Drolet, Jean-Philippe; Martel, Richard

    2016-02-01

    This research was done to demonstrate the usefulness of the local structural geology characteristics to predict indoor radon concentrations. The presence of geologic faults near dwellings increases the vulnerability of the dwellings to elevated indoor radon by providing favorable pathways from the source uranium-rich bedrock units to the surface. Kruskal-Wallis one-way analyses of variance by ranks were used to determine the distance where faults have statistically significant influence on indoor radon concentrations. The great-circle distance between the 640 spatially referenced basement radon concentration measurements and the nearest fault was calculated using the Haversine formula and the spherical law of cosines. It was shown that dwellings located less than 150 m from a major fault had a higher radon potential. The 150 m threshold was determined using Kruskal-Wallis ANOVA on: (1) all the basement radon measurements dataset and; (2) the basement radon measurements located on uranium-rich bedrock units only. The results indicated that 22.8% of the dwellings located less than 150 m from a fault exceeded the Canadian radon guideline of 200 Bq/m(3) when using all the basement radon measurements dataset. This percentage fell to 15.2% for the dwellings located between 150 m and 700 m from a fault. When using only the basement radon measurements located on uranium-rich bedrock units, these percentages were 30.7% (0-150 m) and 17.5% (150 m-700 m). The assessment and management of risk can be improved where structural geology characteristics base maps are available by using this proxy indicator.

  7. Indoor radon levels and lung cancer risk estimates in seven cities of the Bahawalpur Division, Pakistan.

    PubMed

    Matiullah; Ahad, A; Rehman, S; Mirza, M L

    2003-01-01

    Indoor radon concentration levels were measured in seven major cities of the Bahawalpur Division, Pakistan. These included Fort Abbas, Minchin Abad, Hasilpur, Bahawalpur, Liaqatpur, Rahimyar Khan and Sadiq Abad. In order to select houses for this survey, the inhabitants were approached through their school-registered children. Due to several constraints, only those 100 houses were chosen in each city that were relatively the best representatives of the built-up area. The selected houses were then divided into live categories according to the house locations and building characteristics. CR-39 detectors, placed in polyethylene bags. were installed at head height in bedrooms and sitting rooms of all the selected houses and were exposed to radon and its daughter products for 90 days. Four such measurements were performed over a year in order to average out the seasonal variation in radon levels. After exposure, all the detectors were etched and counted under an optical microscope. The track densities of four measurements were averaged out and related to radon concentration levels. The radon levels were found to be 20, 20, 26, 28, 34, 42, 47 Bq m(-3) in the bedrooms and 24, 26, 27, 26, 37, 40, 43 Bq m(-3) in sitting rooms of Hasilpur, Rahimyar Khan, Minchin Abad, Fort Abbas, Sadiq Abad, Bahawalpur and Liaqatpur respectively. The observed variation in the radon level may be attributed to the geological variation in the area. Based on the observed data, excess lung cancer risk was assessed using the risk factors recommended by the USEPA, UNSCEAR and the ICRP. According to the EPA model, the lifetime excess lung cancer risk due to the lifetime exposure is found to vary from 12-102 per million per year in the houses surveyed. This variation is from 16-114 and 26-62 per million per year if UNSCEAR and ICRP limits are applied respectively.

  8. Variation in the annual average radon concentration measured in homes in Mesa County, Colorado

    SciTech Connect

    Rood, A.S.; George, J.L.; Langner, G.H. Jr.

    1990-04-01

    The purpose of this study is to examine the variability in the annual average indoor radon concentration. The TMC has been collecting annual average radon data for the past 5 years in 33 residential structures in Mesa County, Colorado. This report is an interim report that presents the data collected up to the present. Currently, the plans are to continue this study in the future. 62 refs., 3 figs., 12 tabs.

  9. Groundwater treatment as a source of indoor radon.

    PubMed

    Jantsikene, Alar; Kiisk, Madis; Suursoo, Siiri; Koch, Rein; Lumiste, Liie

    2014-11-01

    New Viimsi Parish water treatment plant (Northern Estonia) was investigated in order to determine whether the open filter columns serve as a source of (222)Rn generation in the treatment process and whether they influence indoor air (222)Rn activity concentrations. (222)Rn measurements of indoor (222)Rn were performed at different locations of the treatment plant; water samples from incoming raw water, from all the purification stages, consumers water and solid filter material from two filtration stages were analyzed.

  10. Indoor radon and lung cancer in radium-dial workers

    SciTech Connect

    Neuberger, J.S.; Rundo, J.

    1996-12-31

    Internally deposited radium has long been known to have tumorigenic effects in the form of sarcomas of the bone and carcinomas of the paranasal sinuses and mastoid air cells. However, radium-dial workers were also exposed to radiation hazards other than that occurring from ingestion of the radium paint, namely, external gamma radiation and elevated concentrations of airborne radon. Uranium miners were also exposed to high concentrations of radon in the 1950s and later and numerous cases of lung cancer have occurred in that population. However, unlike the atmosphere in the uranium mines, the air in the dial painting plants was probably rather clean and perhaps not much different from the air in many houses. In view of the current concern over the possibility of lung cancer in the general population being caused by radon (progeny) in houses, it is important to examine the mortality due to this usually fatal disease in the dial workers and to attempt to relate it to their exposure to radon, to the extent that is possible.

  11. Indoor radon and lung cancer in the radium dial workers

    SciTech Connect

    Neuberger, J.S.; Rundo, J.

    1996-12-31

    Internally deposited radium has long been known to have tumorigenic effects in the form of sarcomas of the bone and carcinomas of the paranasal sinuses and mastoid air cells. However, the radium dial workers were also exposed to radiation hazards other than that occurring from ingestion of the radium paint, viz., external gamma radiation and elevated concentrations of airborne radon. The uranium miners were also exposed to high concentrations of radon in the 1950s and later, and numerous cases of lung cancer have occurred in that population. However, unlike the atmosphere in the uranium mines, the air in the dial painting plants was probably rather clean and perhaps not much different from the air in many houses. In view of the current concern over the possibility of lung cancer fin the general population being caused by radon (progeny) in houses, it is important to examine the mortality due to this usually fatal disease in the dial workers and to attempt to relate it to their exposure to radon, to the extent that this is possible.

  12. Study of epidemiological risk of lung cancer in Mexico due indoor radon exposure

    NASA Astrophysics Data System (ADS)

    Ángeles, A.; Espinosa, G.

    2014-07-01

    In this work the lifetime relative risks (LRR) of lung cancer due to exposure to indoor 222Rn on the Mexican population is calculated. Cigarette smoking is the number one risk factor for lung cancer (LC), because that, to calculate the number of cases of LC due to exposure to 222Rn is necessary considers the number of cases of LC for smoking cigarette. The lung cancer mortality rates published by the "Secretaría de Salud" (SSA), the mexican population data published by the "Consejo Nacional de Población" (CONAPO), smoking data in the mexican population, published by the "Comisión Nacional Contra las Adicciones" (CONADIC), the "Organización Panamericana de la Salud" (OPS) and indoor 222Rn concentrations in Mexico published in several recent studies are used. To calculate the lifetime relative risks (LRR) for different segments of the Mexican population, firstly the Excess Relative Risk (ERR) is calculated using the method developed by the BEIR VI committee and subsequently modified by the USEPA and published in the report "EPA Assessment of Risks from Radon in Homes". The excess relative risks were then used to calculate the corresponding lifetime relative risks, again using the method developed by the BEIR VI committee. The lifetime relative risks for Mexican male and female eversmokers and Mexican male and female never-smokers were calculated for radon concentrations spanning the range found in recent studies of indoor radon concentrations in Mexico. The lifetime relative risks of lung cancer induced by lifetime exposure to the mexican average indoor radon concentration were estimated to be 1.44 and 1.40 for never-smokers mexican females and males respectively, and 1.19 and 1.17 for ever-smokers Mexican females and males respectively. The Mexican population LRR values obtained in relation to the USA and Canada LRR published values in ever-smokers for both gender are similar with differences less than 4%, in case of never-smokers in relation with Canada

  13. Indoor radon survey in a university campus of Nigeria

    PubMed Central

    Obed, R. I.; Lateef, H. T.; Ademola, A. K.

    2010-01-01

    CR-39 tracketch detectors were used for the measurement of 222Rn concentration in 24 offices in Nigeria’s oldest university campus in order to estimate the effective dose to the occupants from 222Rn and its progeny. The dosimetric measurements were made over a period of 3 months. Questionnaires were distributed and analyzed. The radon concentration ranged from 157 to 495 Bq/m3, with an arithmetic mean and standard deviation of 293.3 and 79.6 Bq/ m3, respectively. The effective dose to the workers was estimated and this varied from 0.99 to 3.12 mSv/ y, with a mean of 1.85 mSv/y. The radon concentrations were found to be within the reference levels of ICRP. PMID:21170190

  14. Indoor radon survey in a university campus of Nigeria.

    PubMed

    Obed, R I; Lateef, H T; Ademola, A K

    2010-10-01

    CR-39 tracketch detectors were used for the measurement of (222)Rn concentration in 24 offices in Nigeria's oldest university campus in order to estimate the effective dose to the occupants from (222)Rn and its progeny. The dosimetric measurements were made over a period of 3 months. Questionnaires were distributed and analyzed. The radon concentration ranged from 157 to 495 Bq/m(3), with an arithmetic mean and standard deviation of 293.3 and 79.6 Bq/ m(3), respectively. The effective dose to the workers was estimated and this varied from 0.99 to 3.12 mSv/ y, with a mean of 1.85 mSv/y. The radon concentrations were found to be within the reference levels of ICRP.

  15. POSSIBLE ROLE OF INDOOR RADON REDUCTION SYSTEMS IN BACK-DRAFTING RESIDENTIAL COMBUSTION APPLIANCES

    EPA Science Inventory

    The article gives results of a computational sensitivity analysis conducted to identify conditions under which residential active soil depressurization (ASD) systems for indoor radon reduction might contribute to or create back-drafting of natural draft combustion appliances. Par...

  16. Assessment of the dose received by students and staff in schools in the Rawalpindi region of Pakistan due to indoor radon.

    PubMed

    Rahman, S U; Matiullah; Anwar, J

    2009-06-01

    Studies concerning measurements of indoor radon levels were carried out in 60 schools in the Rawalpindi region of Pakistan. In each school, six CR-39 based NRPB type radon detectors were installed and exposed to the indoor radon in two cycles (each of six months' duration). After exposure, the detectors were removed, etched in 6 M NaOH for 16 h at 80 degrees C, and the tracks were counted under an optical microscope. The measured track densities were then related to radon concentrations, from which the radiation doses were calculated. The observed radon concentrations varied from 15 to 140 Bq m(-3), with an average activity concentration of 42.75 +/- 9.28 Bq m(-3). The mean annual radon effective dose equivalent was found to be 0.40 +/- 0.09 mSv using an occupancy factor of 8 h day(-1). Our results show that the indoor radon concentrations in the schools surveyed are within the permissible limits.

  17. Po-210 as long-term integrating radon indicator in the indoor environment

    SciTech Connect

    Samuelsson, C.

    1990-07-01

    The general objective is to improve the knowledge about the transferring processes leading from airborne radon/radon daughters to embedded Po-210 in hard surfaces in the indoor environment. The specific goal of the research is to identify situations in which the surface activity of Po-210 can be used as a long-term indicator of lung cancer risk from past or future radon exposures.

  18. Shelter and indoor air in the twenty-first century: Radon, smoking and lung cancer risks

    SciTech Connect

    Fabrikant, J.I.

    1988-04-01

    This document describes the relationship between indoor radon exposure, cigarette smoking, and lung cancer. The author explains the sources of radon, the tissues at risk, the human populations most likely to be affected, and the estimates of lung cancer in the population. 6 refs., 2 tabs. (TEM)

  19. Indoor air quality in the Karns research houses: baseline measurements and impact of indoor environmental parameters on formaldehyde concentrations

    SciTech Connect

    Matthews, T. G.; Fung, K. W.; Tromberg, B. J.; Hawthorne, A. R.

    1985-12-01

    Baseline indoor air quality measurements, a nine-month radon study, and an environmental parameters study examining the impact of indoor temperature (T) and relative humidity (RH) levels on formaldehyde (CH2O) concentrations have been performed in three unoccupied research homes located in Karns, Tennessee. Inter-house comparison measurements of (1) CH2O concentration, (2) CH20 emission rates from primary CH20 emission sources, (3) radon and radon daughter concentrations, and (4) air exchange rates indicate that the three homes are similar. The results of the nine-month radon study indicate indoor concentrations consistently below the EPA recommended level of 4 pCi/L. Evidence was found that crawl-space concentrations may be reduced using heat pump systems whose outdoor units circulate fresh air through the crawl-spaoe. The modeled results of the environmental parameters study indicate approximate fourfold increases in CH20 concentrations from 0.07 to 0.27 ppm for seasonal T and RH conditions of 20°C, 30% RH and 29°C, 80% RH, respectively. Evaluation of these environmental parameters study data with steady-state CH2O concentration models developed from laboratory studies of the environmental dependence of CH2O emissions from particleboard underlayment indicate good correlations between the laboratory and field studies.

  20. Lung cancer mortality and radon concentration in a chronically exposed neighborhood in Chihuahua, Mexico: a geospatial analysis.

    PubMed

    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.

  1. Lung Cancer Mortality and Radon Concentration in a Chronically Exposed Neighborhood in Chihuahua, Mexico: A Geospatial Analysis

    PubMed Central

    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/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. PMID:25165752

  2. Radon concentrations in residential housing in Hiroshima and Nagasaki

    SciTech Connect

    Yonehara, Hidenori; Aoyama, Takashi; Radford, E.P.

    1995-05-01

    A measurement of indoor radon ({sup 222}Rn) concentrations in Hiroshima and Nagasaki was carried out to assess the variability of exposure expected among atomic bomb survivors. Two hundred dwellings, mostly belonging to members of the fixed cohort of atomic bomb survivors under study by the Radiation Effects Research Foundations, were selected for this measurement. The geometric mean values of the radon concentrations for 100 dwellings in Hiroshima and 99 dwellings in Nagasaki measured by Track-Etcho Type SF detectors were 56.8 Bq m{sup {minus}3} and 28.5 Bq m{sup {minus}3}, respectively. No statistically significant difference was observed between lung cancer mortalities in the low-dose range in the two cities. However, apparent values of the mortality rate for low dose range in Hiroshima are consistently greater than those in Nagasaki. The exposure to radon and its progeny and the atomic bomb radiation effect might have some cooperative effects on the lung cancer incidence.

  3. Evaluation of the uniformity of concentration of radon in a radon chamber.

    PubMed

    Xiongjie, Zhang; Ye, Zhang; Yang, Liu; Bin, Tang

    2016-04-01

    In order to solve the problem that the evaluation results of the uniformity of concentration of radon in a radon chamber via various methods were difficult to compare, according to its statistical properties, a mathematical model was built to analyze the uniformity of concentration of radon; an evaluation method for the overall uniformity of concentration of radon was proposed on the basis of single-factor multi-group ANOVA, and a detection method for nonuniform points in a radon chamber was proposed on the basis of single-factor two-group t-test; an evaluation process of the uniformity of concentration of radon in a radon chamber was established. The proposed method was applied to evaluate the HD-6 small and medium-sized radon chambers and achieved good results. PMID:26821207

  4. The effects of geology and the impact of seasonal correction factors on indoor radon levels: a case study approach.

    PubMed

    Gillmore, Gavin K; Phillips, Paul S; Denman, Antony R

    2005-01-01

    Geology has been highlighted by a number of authors as a key factor in high indoor radon levels. In the light of this, this study examines the application of seasonal correction factors to indoor radon concentrations in the UK. This practice is based on an extensive database gathered by the National Radiological Protection Board over the years (small-scale surveys began in 1976 and continued with a larger scale survey in 1988) and reflects well known seasonal variations observed in indoor radon levels. However, due to the complexity of underlying geology (the UK arguably has the world's most complex solid and surficial geology over the shortest distances) and considerable variations in permeability of underlying materials it is clear that there are a significant number of occurrences where the application of a seasonal correction factor may give rise to over-estimated or under-estimated radon levels. Therefore, the practice of applying a seasonal correction should be one that is undertaken with caution, or not at all. This work is based on case studies taken from the Northamptonshire region and comparisons made to other permeable geologies in the UK.

  5. Lung Cancer Attributable to Indoor Radon Exposures in Two Radon—Prone Areas, Ştei (Romania) and Torrelodones (Spain)

    NASA Astrophysics Data System (ADS)

    Dinu, Alexandra; Cosma, Constantin; Sainz, Carlos; Poncela, Luis Santiago Quindós; Vasiliniuc, Ştefan

    2009-05-01

    Radon and radon progeny are present indoors, in houses and others dwellings, representing the most important contribution to dose from natural sources of radiation. Most studies have demonstrated an increased risk of lung cancer at high concentration of radon for both smokers and nonsmokers. For medium and low concentrations which are the typical residential radon levels, recent researches have also demonstrated increased risks of lung cancer for people exposed. The work presents a comparative analysis of the radon exposure data in the two radon—prone areas, Ştei, Transylvania, (Romania), in the near of old Romanian uranium mines and in the granitic area of Torrelodones town, Sierra de Guadarrama (Spain). One important difference between the two studied areas is related to the houses built using uranium waste as construction material in Ştei area. Measurements of indoor radon were performed in 280 dwellings (Romania) and 91 dwellings (Spain) by using nuclear track detectors, CR 39. The highest value measured in Ştei area was 2650 Bqṡm-3. and 366 Bqṡm-3 in the Spanish region. The results are compute with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bqṡm-3. A total of 233 lung cancer deaths were calculated in the Ştei area for a period of 13 years (1994-2006), which is 116.82% higher than observed from the national statistics. In comparison, in Torrelodones area, a number of 276 deaths caused by lung cancer were estimated along a period of 13 years, which is 2.09 times higher than the number observed by authorities. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure.

  6. Reducing indoor air formaldehyde concentrations

    SciTech Connect

    Meyer, B.; Hermanns, K.

    1985-08-01

    Urea-formaldehyde resin bonded particle board, medium density fiberboard and plywood paneling are used as flooring, wall paneling, for cabinet work and in furniture, and are present in almost every office, home and public building. If large quantities of these products are used in poorly ventilated spaces, high manufacturing quality control is necessary to avoid problems of latent formaldehyde release. Indoor air formaldehyde concentrations depend on the nature of the product, the product surface to air volume (loading) factor, temperature, humidity, age and product emission rates. Standard test methods are now available for measuring product emission rates that make it possible to predict the performance of UF-bonded pressed wood materials if use conditions and environmental parameters are known. Recent modifications in adhesive and board manufacturing parameters have made it possible to reduce formaldehyde emission significantly, and UF-bonded wood products are now capable of meeting indoor air quality standard levels of 0.1 ppm under almost all customary loading conditions.

  7. The indoor radon problem: Studies in the Albuquerque, New Mexico area

    NASA Astrophysics Data System (ADS)

    Brookins, Douglas G.

    1988-12-01

    Radon buildup in homes is now recognized throughout the world as a potentially major health hazard. The U.S. Nuclear Regulatory Commission and the U.S. Environmental Protection Agency estimate 8,000 30,000 fatalities per year in the United States due to indoor radon. The Albuquerque, New Mexico area was chosen for study because it is representative of metropolitan areas in the southwestern United States where slightly uraniferous source rocks (Sandia granite) have provided the very immature soil for much of the area. The granite contains 4.7 ppm U, and limestone capping the granite 5.7 ppm U. Soils in the area average 4.24 ppm U, and Th/U ratios average 3.2. These data suggest some removal of U from the source rocks, but fixation of the U in the soils (that is, as opposed to widespread removal of the U by solution), thus providing a ready source for soil radon. A pilot study of soil radon in the area in winter of 1983 1984 shows high values, 180 pCi/l, relative to the U.S. average (about 100 pCi/l). In the winter of 1986 1987, 180 dwellings were surveyed for their indoor radon levels, including 20 that had been surveyed in summer of 1986. Twenty-eight percent of those in the winter study yielded indoor radon above the EPA suggested maximum permissible level of 4 pCi/l air, well above the EPA estimate of 10 15 dwellings for the U.S. The indoor radon levels show positive correlation with closeness to the Sandia Mountains, to soil radon, to excess insulation, to homes with solar capacities, and other factors. Building materials may provide a very minor source of some indoor radon. Summer readings are lower than winter readings except when the houses possess refrigerated air conditioning.

  8. Concentration en radon dans une maison du Calvados

    NASA Astrophysics Data System (ADS)

    Leleyter, Lydia; Riffault, Benoit; Mazenc, Bernard

    2010-03-01

    Recent studies indicate a link between the risk of lung cancer and residential radon exposure. However, in France, awareness of this problem was made relatively late. Accordingly this study examines the radon concentration in a private home in Calvados. Findings show that the presence of a fireplace in a house can accelerate radon convective transfer, and that simple adjustments to interior and exterior accommodation can significantly reduce radon concentrations in the home.

  9. Measurements of radon concentrations in Spa waters in Amasya, Turkey

    NASA Astrophysics Data System (ADS)

    Yigitoglu, I.; Oner, F.; Yalim, H. A.; Ucar, B.

    2016-04-01

    The aim of this study is to determine the radon concentrations in thermal waters in the Amasya basin in Turkey and to explore the relationship between radon anomalies and active geological faults. The radon concentration measurements were performed in four thermal Spas around Amasya basin. The water samples were collected from tap waters in thermal water sources. The obtained radon concentrations ranged from 0.15 ± 0.12 to 0.71 ± 0.32 BqL-1 for Spa waters. The relationship between the radon concentration anomalies and earthquakes that occurred in the sampling period are discussed.

  10. Variations of radon and thoron concentrations in different types of dwellings in Mysore city, India.

    PubMed

    Shashikumar, T S; Chandrashekara, M S; Nagaiah, N; Paramesh, L

    2009-01-01

    (222)Rn and (220)Rn, the immediate decay products of radium isotopes, are causative agents of lung cancer. (222)Rn and (220)Rn concentrations in houses with different floorings, roofs and walls and in different rooms of houses have been measured in Mysore city, Karnataka state, India, using solid-state nuclear track detectors. The radon and thoron concentrations in dwellings with granite floorings are found to be higher compared with other types. A correlation between the indoor radon concentration and dose in air from terrestrial gamma radiation is observed.

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

    PubMed

    Somlai, János; Gorjánácz, Zorán; Várhegyi, András; Kovács, Tibor

    2006-08-31

    High radon concentration (average 410 kBq m-3) has been measured in a tunnel of a uranium mine, located 15-55 m below the village of Kovágószolos, 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-3. Significantly higher radon concentrations (average 667 Bq m-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-3). The average radon concentration of the soil gas was 88.8 kBq m-3, the average radon exhalation was 71.4 Bq m-2 s-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-3) may influence the radon concentration of the houses over the mining tunnel.

  12. RAETRAD MODEL OF RADON GAS GENERATION, TRANSPORT, AND INDOOR ENTRY

    EPA Science Inventory

    The report describes the theoretical basis, implementation, and validation of the Radon Emanation and Transport into Dwellings (RAETRAD) model, a conceptual and mathematical approach for simulating radon (222Rn) gas generation and transport from soils and building foundations to ...

  13. The relation of seismic activity and radon concentration

    SciTech Connect

    Kulali, Feride E-mail: iskender@fef.sdu.edu.tr; Akkurt, İskender E-mail: iskender@fef.sdu.edu.tr; Vogiannis, Efstratios

    2014-10-06

    Radon, which is the largest source of natural ionizing radiation, reaches to surface as gas or dissolved form in the ground water. Emanation of radon can has a profile is disposed to increasing or decreasing depending on the effects of meteorological events or crust movements. In this work, the radon concentration in soil gas, which is transported from soil to AlphaGUARD, is continuously measured in Mytilene (Greece). A graph of radon concentration is prepared for comparison with simultaneous earthquake data. As a consequence of comparison, we determined that the radon concentration indicates anomalies before the earthquakes.

  14. The relation of seismic activity and radon concentration

    NASA Astrophysics Data System (ADS)

    Kulali, Feride; Akkurt, Iskender; Vogiannis, Efstratios

    2014-10-01

    Radon, which is the largest source of natural ionizing radiation, reaches to surface as gas or dissolved form in the ground water. Emanation of radon can has a profile is disposed to increasing or decreasing depending on the effects of meteorological events or crust movements. In this work, the radon concentration in soil gas, which is transported from soil to AlphaGUARD, is continuously measured in Mytilene (Greece). A graph of radon concentration is prepared for comparison with simultaneous earthquake data. As a consequence of comparison, we determined that the radon concentration indicates anomalies before the earthquakes.

  15. Field experience on indoor radon, thoron and their progenies with solid-state detectors in a survey of Kosovo and Metohija (Balkan region).

    PubMed

    Gulan, L; Milic, G; Bossew, P; Omori, Y; Ishikawa, T; Mishra, R; Mayya, Y S; Stojanovska, Z; Nikezic, D; Vuckovic, B; Zunic, Z S

    2012-11-01

    Since 1996/97, indoor radon has been measured in scattered locations around Kosovo. In the most recent campaign, apart from radon, thoron and Rn and Tn progenies have also been measured. The current survey involves 48 houses, in which different detectors have been deployed side-by-side in one room, in order to measure indoor radon and thoron gas with RADUET devices based on CR-39 detectors (analysed by Japanese collaborators) and with direct thoron and radon progeny sensor (DTPS and DRPS) devices based on LR-115 detectors (analysed by collaborators from India). Estimated arithmetic mean values of concentrations in 48 houses are 122 Bq m(-3) for radon and 136 Bq m(-3) for thoron. Those for equilibrium equivalent radon concentration and equilibrium equivalent thoron concentration based on measurements in 48 houses are 40 and 2.1 Bq m(-3), respectively. The arithmetic mean value of the equilibrium factor is estimated to be 0.50 ± 0.23 for radon and 0.037 ± 0.041 for thoron. The preliminary results of these measurements are reported, particularly regarding DTPS and DRPS being set up in real field conditions for the first time in the Balkan region. The results are to be understood under the caveat of open questions related to measurement protocols which yield reproducible and representative results, and to quality assurance of Tn and Rn/Tn progeny measurements in general, some of which are discussed.

  16. Measurement of radon concentrations at Super-Kamiokande

    NASA Astrophysics Data System (ADS)

    Takeuchi, Y.; Okumura, K.; Kajita, T.; Tasaka, S.; Nemoto, M.; Fukuda, Y.; Okazawa, H.; Hayakawa, T.; Ishihara, K.; Ishino, H.; Itow, Y.; Kameda, J.; Kasuga, S.; Kobayashi, K.; Kobayashi, Y.; Koshio, Y.; Miura, M.; Nakahata, M.; Nakayama, S.; Obayashi, Y.; Okada, A.; Sakurai, N.; Shiozawa, M.; Suzuki, Y.; Takeuchi, H.; Totsuka, Y.; Yamada, S.; Earl, M.; Habig, A.; Kearns, E.; Messier, M. D.; Scholberg, K.; Stone, J. L.; Sulak, L. R.; Walter, C. W.; Goldhaber, M.; Barszczak, T.; Casper, D.; Gajewski, W.; Kropp, W. R.; Mine, S.; Price, L. R.; Smy, M.; Sobel, H. W.; Vagins, M. R.; Ganezer, K. S.; Keig, W. E.; Ellsworth, R. W.; Kibayashi, A.; Learned, J. G.; Matsuno, S.; Stenger, V. J.; Takemori, D.; Ishii, T.; Kanzaki, J.; Kobayashi, T.; Nakamura, K.; Nishikawa, K.; Oyama, Y.; Sakai, A.; Sakuda, M.; Sasaki, O.; Echigo, S.; Kohama, M.; Suzuki, A. T.; Haines, T. J.; Blaufuss, E.; Kim, B. K.; Sanford, R.; Svoboda, R.; Chen, M. L.; Goodman, J. A.; Sullivan, G. W.; Hill, J.; Jung, C. K.; Martens, K.; Mauger, C.; McGrew, C.; Sharkey, E.; Viren, B.; Yanagisawa, C.; Doki, W.; Kirisawa, M.; Inaba, S.; Miyano, K.; Saji, C.; Takahashi, M.; Takahata, M.; Higuchi, K.; Nagashima, Y.; Takita, M.; Yamaguchi, T.; Yoshida, M.; Kim, S. B.; Etoh, M.; Hasegawa, A.; Hasegawa, T.; Hatakeyama, S.; Inoue, K.; Iwamoto, T.; Koga, M.; Maruyama, T.; Ogawa, H.; Shirai, J.; Suzuki, A.; Tsushima, F.; Koshiba, M.; Hatakeyama, Y.; Koike, M.; Nishijima, K.; Fujiyasu, H.; Futagami, T.; Hayato, Y.; Kanaya, Y.; Kaneyuki, K.; Watanabe, Y.; Kielczewska, D.; George, J. S.; Stachyra, A. L.; Wai, L. L.; Wilkes, R. J.; Young, K. K.

    1999-04-01

    Radioactivity from radon is a major background for observing solar neutrinos at Super-Kamiokande. In this paper, we describe the measurement of radon concentrations at Super-Kamiokande, the method of radon reduction, and the radon monitoring system. The measurement shows that the current low-energy event rate between 5.0 MeV and 6.5 MeV implies a radon concentration in the Super-Kamiokande water of less than 1.4 mBq/m3.

  17. Reducing indoor radon levels in a UK test house using different ventilation strategies

    SciTech Connect

    Welsh, P.A.

    1995-12-31

    This paper reports on some of the most recent tests involving a number of studies in an unoccupied radon test house. The house has a suspended timber floor and naturally elevated indoor radon levels, peaking at times above 6000 Bqm{sup -3}. Various sensors monitor how different ventilation strategies affect indoor radon levels and the building environment. Data from five different scenarios is presented. Initially the house was monitored as purchased with poor natural underfloor ventilation. This was followed by testing whole house pressurisation, improved natural underfloor ventilation, and two types of mechanical underfloor ventilation. The results from these and future studies may be used to make a more informed choice of remedy, based on a whole number of aspects, not only radon reduction as is frequently the case.

  18. Indoor radon risk associated to post-tectonic biotite granites from Vila Pouca de Aguiar pluton, northern Portugal.

    PubMed

    Martins, L M O; Gomes, M E P; Teixeira, R J S; Pereira, A J S C; Neves, L J P F

    2016-11-01

    At Vila Pouca de Aguiar area, northern Portugal, crops out a post-tectonic Variscan granite pluton, related with the Régua-Vila Real-Verín fault zone, comprising three types of biotite granites. Among these granites, PSG granite yield the highest average contents of U, probably due to its enrichment in accessory U-bearing minerals such as zircon. In the proximity of faults and joints, these granites are often affected by different degrees of hydrothermal alteration, forming reddish altered rocks, commonly known as "episyenites". These altered rocks are probably associated to the occurrence of hydrothermal processes, which led to uranium enrichment in the most advanced stages of episyenitization. In these granites, both average gamma absorbed dose rates in outdoor and indoor air are higher than those of the world average. Furthermore, even in the worst usage scenario, all these granites can be used as a building material, since their annual effective doses are similar to the limit defined by the European Commission. The geometric mean of radon activity of 91 dwellings located at the Vila Pouca de Aguiar pluton is 568Bqm(-3), exceeding that of other northern Portuguese granites. Measurements carried out during a winter season, indicate that 62.6% of the analysed dwellings yield higher indoor radon average values than the Portuguese legislation limit (400Bqm(-3)), and annual effective doses due higher than the world's average value (1.2mSvy(-1)). The interaction of geogenic, architectural and anthropogenic features is crucial to explain the variance in the geometric mean of radon activity of dwellings from Vila Pouca de Aguiar pluton, but the role of geologic faults is probably the most important decisive factor to increase the indoor radon concentration in dwellings. Hence, the development of awareness campaigns in order to inform population about the incurred radiological risks to radon exposure are highly recommended for this specific area. PMID:27448957

  19. Indoor radon risk associated to post-tectonic biotite granites from Vila Pouca de Aguiar pluton, northern Portugal.

    PubMed

    Martins, L M O; Gomes, M E P; Teixeira, R J S; Pereira, A J S C; Neves, L J P F

    2016-11-01

    At Vila Pouca de Aguiar area, northern Portugal, crops out a post-tectonic Variscan granite pluton, related with the Régua-Vila Real-Verín fault zone, comprising three types of biotite granites. Among these granites, PSG granite yield the highest average contents of U, probably due to its enrichment in accessory U-bearing minerals such as zircon. In the proximity of faults and joints, these granites are often affected by different degrees of hydrothermal alteration, forming reddish altered rocks, commonly known as "episyenites". These altered rocks are probably associated to the occurrence of hydrothermal processes, which led to uranium enrichment in the most advanced stages of episyenitization. In these granites, both average gamma absorbed dose rates in outdoor and indoor air are higher than those of the world average. Furthermore, even in the worst usage scenario, all these granites can be used as a building material, since their annual effective doses are similar to the limit defined by the European Commission. The geometric mean of radon activity of 91 dwellings located at the Vila Pouca de Aguiar pluton is 568Bqm(-3), exceeding that of other northern Portuguese granites. Measurements carried out during a winter season, indicate that 62.6% of the analysed dwellings yield higher indoor radon average values than the Portuguese legislation limit (400Bqm(-3)), and annual effective doses due higher than the world's average value (1.2mSvy(-1)). The interaction of geogenic, architectural and anthropogenic features is crucial to explain the variance in the geometric mean of radon activity of dwellings from Vila Pouca de Aguiar pluton, but the role of geologic faults is probably the most important decisive factor to increase the indoor radon concentration in dwellings. Hence, the development of awareness campaigns in order to inform population about the incurred radiological risks to radon exposure are highly recommended for this specific area.

  20. A study of atmospheric radon gas concentrations in water extraction wells of Hamadan, western Iran.

    NASA Astrophysics Data System (ADS)

    Gillmore, Gavin; Jabari Vasal, Naghi

    2010-05-01

    It is well known that half of the radiation received by humans is due to the presence of radon (222Rn) in the built environment. As part of a project measuring indoor radon in Hamadan, western Iran, a survey was undertaken of atmospheric radon in 28 wells in the region using a Sarad Doseman. Specific geological features of this settlement include highly permeable alluvial fan deposits which result in radon being released to the atmosphere. The observed radon concentrations in well shafts(between 1,000 Bq m3 and 36,600 Bq m3) show considerable variability both in space and time. One aspect of this study was to also assess whether there was a relationship between the depth of a well and the measured atmospheric radon concentration. The importance of such measurements in this region is highlighted by the fact that radon levels in homes in Hamadan are probably greatly influenced by the porous nature of this underlying geology and its use as a water reservoir / conduit through the application of qanat technology.

  1. Indoor radon and lung cancer: Reality or Myth? Part 1

    SciTech Connect

    Cross, F.T.

    1992-12-31

    The Twenty-Ninth Hanford Symposium on Health and the Environment, was held in Richland, Washington, on October 15--19, 1990. At the time of the Symposium, significant results were beginning to emerge from the recently initiated, multidisciplinary Department of Energy (DOE) Radon Program and from the Commission of European Communities (CEC) radon-related studies. Therefore, it was the intent of the organizers to broaden the base of topics on the radon issue that would be discussed at the symposium while, at the same time, emphasizing the health-effect studies. Sessions of the symposium included: radon and progeny exposure assessment; dosimetry modeling; radon transport in soils and into structures; radon and radon progeny sources; methods to control radon and radon progeny exposure; molecular/cellular-level studies; animal studies and exposure systems; biological and statistical modeling studies; epidemiologic studies; public strategy, information, and risk communication; and scientific activities and programs to understand and control exposure to radon (panel). Individual abstracts have been processed separately for the database.

  2. Design and Fabrication of A Modern Radon-Tight Chamber for Radon Concentration Measurements

    NASA Astrophysics Data System (ADS)

    Alhalemi, Ahmed; Jaafar, M. S.

    2010-07-01

    A modern radon-tight chamber (RTC) has been designed and fabricated to meet the request and requirements for both the Professional Continuous Radon Monitor (PCRM), and the RAD7 radon detector. The chamber is cubic shaped, made of Perspex with a volume of about 0.125 m3. The RTC was also equipped with a thermometer and a humidity sensor. A pair of gloves was attached on one side of the chamber's lateral opening for operating the PCRM. In addition, a fan was installed to circulate the air, and to distribute the radon gas to ensure homogeneity after the air inside the chamber is evacuated with nitrogen gas. At the end of the monitoring period, the results of the concentration of the radon emanated from a sample placed inside the chamber will then be available in any of three forms: numerical display on the control panel of the radon detector, printed report on the accessory printer, or transferred into a file on a personal computer via the RS-232 Serial port without disturbing the radon concentration inside the chamber. Computer software is provided by the manufacturer for this purpose. The result of analysis was presented in a one-way ANOVA that indicated that the radon concentration means are not difference for the three different positions of the PCRM (P > 0.05). Thus, this RTC can be used to measure the radon concentration and its progeny; in addition, it can be used for research and useful studies on radon exhalation from building materials.

  3. Estimation of past radon exposure to indoor radon from embedded (210)Po in household glass.

    PubMed

    Gusain, G S; Rautela, B S; Ramola, R C

    2012-11-01

    In the present investigation, the surface-deposited polonium activities were measured in houses in the Ukhimath region of Garhwal Himalaya, India. The surface-deposited (210)Po activity concentrations were found to vary from 0.7 to 15.40 Bq m(-2) with an average of 5.95 Bq m(-2). The radon concentration estimated on the basis of (210)Po activity was found to vary from 0.29 to 700 Bq m(-3) with an average value 242 Bq m(-3). The contemporary radon concentration in the area was found to vary from 13 to 181 Bq m(-3) with an average of 46 Bq m(-3). The annual effective dose due to (210)Po activity in houses in the Garhwal Himalaya region was found to vary from 0.61 to 13.33 mSv with an average of 5.15 mSv. Some worldwide studies have shown the relation between the increased risk of lung cancer and smoking habits. Data on smoking have also been collected from the same dwellings. The significance of this work is also discussed in detail from a radiation protection point of view.

  4. Radon Concentration in the Drinking Water of Aliabad Katoul, Iran

    PubMed Central

    Adinehvand, Karim; Sahebnasagh, Amin; Hashemi-Tilehnoee, Mehdi

    2016-01-01

    Background According to the world health organization, radon is a leading cause of cancer in various internal organs and should be regarded with concern. Objectives The aim of this study is to evaluate the concentration of soluble radon in the drinking water of the city of Aliabad Katoul, Iran. Materials and Methods The radon concentration was measured by using a radon meter, SARADTM model RTM 1688-2, according to accepted standards of evaluation. Results The mean radon concentration in the drinking water of Aliabad Katoul is 2.90 ± 0.57 Bq/L. Conclusions The radon concentration in Aliabad Katoul is below the limit for hazardous levels, but some precautions will make conditions even safer for the local populace. PMID:27651948

  5. Radon Concentration in the Drinking Water of Aliabad Katoul, Iran

    PubMed Central

    Adinehvand, Karim; Sahebnasagh, Amin; Hashemi-Tilehnoee, Mehdi

    2016-01-01

    Background According to the world health organization, radon is a leading cause of cancer in various internal organs and should be regarded with concern. Objectives The aim of this study is to evaluate the concentration of soluble radon in the drinking water of the city of Aliabad Katoul, Iran. Materials and Methods The radon concentration was measured by using a radon meter, SARADTM model RTM 1688-2, according to accepted standards of evaluation. Results The mean radon concentration in the drinking water of Aliabad Katoul is 2.90 ± 0.57 Bq/L. Conclusions The radon concentration in Aliabad Katoul is below the limit for hazardous levels, but some precautions will make conditions even safer for the local populace.

  6. Normal seasonal variations for atmospheric radon concentration: a sinusoidal model.

    PubMed

    Hayashi, Koseki; Yasuoka, Yumi; Nagahama, Hiroyuki; Muto, Jun; Ishikawa, Tetsuo; Omori, Yasutaka; Suzuki, Toshiyuki; Homma, Yoshimi; Mukai, Takahiro

    2015-01-01

    Anomalous radon readings in air have been reported before an earthquake activity. However, careful measurements of atmospheric radon concentrations during a normal period are required to identify anomalous variations in a precursor period. In this study, we obtained radon concentration data for 5 years (2003-2007) that can be considered a normal period and compared it with data from the precursory period of 2008 until March 2011, when the 2011 Tohoku-Oki Earthquake occurred. Then, we established a model for seasonal variation by fitting a sinusoidal model to the radon concentration data during the normal period, considering that the seasonal variation was affected by atmospheric turbulence. By determining the amplitude in the sinusoidal model, the normal variation of the radon concentration can be estimated. Thus, the results of this method can be applied to identify anomalous radon variations before an earthquake.

  7. Investigating Indoor Radon Levels and Influencing Factors in Primary Schools of Zulfi City, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Al-Ghamdi, S. S.; Al-Garawi, M. S.; Al-Mosa, Tahani M.; Baig, M. R.

    2011-10-01

    Measurement of indoor Concentrations were performed in Zulfi city of Saudi Arabia, using CR-39 track etch detectors. This investigation focused on the influence of different parameters, namely different locations, school categories, school building types, and room type as well as on the existence of differences in radon concentration at floor levels. We divided the Zulfi city into five regions, keeping in mind their geographical locations between Tuwaiq Mountains and Al-Thuwayrat sands. The measured average radon concentrations for regions 1-5 respectively are: 87.0±14.2 Bq/m3, 83.4±6.0 Bq/m3, 61.6±6.4 Bq/m3, 63.7±5.4 Bq/m3 and 87.5±6.Bq/m3 and the minimum concentrations are 28.0 Bq/m3, 5.5 Bq/m3, 1.1 Bq/m3, 1.0 Bq/m3 and 24 Bq/m3 respectively. These results are still within normal limits and below the action level of 148 Bqm-3 set by the U.S. Environmental Protection Agency (EPA). A test of significance using Minitab program was applied to investigate if radon levels in regions are significantly different from each other. We tried all combinations, and found the following results. The "within regions" (different location) test yielded, region 2 is not significant versus region "1" (p = 0.783) and versus region "5" (P = 0.646), whereas it is significant versus region "3" ( P = 0.0160) and also versus region "4" (p = 0.018). We investigated government and rented school's building also and none was found significantly different (p = 0.052). Floors of the same building were tested in order to examine the radon concentration as a function of storey level. No significant difference was observed at floor levels (p = 0.009). When girl's schools versus Boys and kindergartens schools were tested they were found significantly different. It is believed that this significant difference is due to geographical nature of the area, since most of the girl's schools were selected from regions 2 and 3, these regions are relatively close to the Tuwaiq mountains whereas other

  8. Investigating Indoor Radon Levels and Influencing Factors in Primary Schools of Zulfi City, Saudi Arabia

    SciTech Connect

    Al-Ghamdi, S. S.; Al-Garawi, M. S.; Al-Mosa, Tahani M.; Baig, M. R.

    2011-10-27

    Measurement of indoor Concentrations were performed in Zulfi city of Saudi Arabia, using CR-39 track etch detectors. This investigation focused on the influence of different parameters, namely different locations, school categories, school building types, and room type as well as on the existence of differences in radon concentration at floor levels. We divided the Zulfi city into five regions, keeping in mind their geographical locations between Tuwaiq Mountains and Al-Thuwayrat sands. The measured average radon concentrations for regions 1-5 respectively are: 87.0{+-}14.2 Bq/m{sup 3}, 83.4{+-}6.0 Bq/m{sup 3}, 61.6{+-}6.4 Bq/m{sup 3}, 63.7{+-}5.4 Bq/m{sup 3} and 87.5{+-}6.Bq/m{sup 3} and the minimum concentrations are 28.0 Bq/m{sup 3}, 5.5 Bq/m{sup 3}, 1.1 Bq/m{sup 3}, 1.0 Bq/m{sup 3} and 24 Bq/m{sup 3} respectively. These results are still within normal limits and below the action level of 148 Bqm{sup -3} set by the U.S. Environmental Protection Agency (EPA). A test of significance using Minitab program was applied to investigate if radon levels in regions are significantly different from each other. We tried all combinations, and found the following results. The ''within regions''(different location) test yielded, region 2 is not significant versus region ''1''(p = 0.783) and versus region ''5''(P = 0.646), whereas it is significant versus region ''3''(P = 0.0160) and also versus region ''4''(p = 0.018). We investigated government and rented school's building also and none was found significantly different (p = 0.052). Floors of the same building were tested in order to examine the radon concentration as a function of storey level. No significant difference was observed at floor levels (p = 0.009). When girl's schools versus Boys and kindergartens schools were tested they were found significantly different. It is believed that this significant difference is due to geographical nature of the area, since most of the girl's schools were selected from regions 2 and

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

    SciTech Connect

    Hopke, P.K.

    1996-09-01

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

  10. High Radon concentration in the karst area of south Puglia, Italy

    NASA Astrophysics Data System (ADS)

    Taroni, Mattia; Bartolomei, Paolo; Esposito, Massimo; Vaccaro, Carmela

    2010-05-01

    foreseen: Samples of rocks and soils to determine the Uranium concentration; Collection of water samples for the determination of Radon concentrations; Measurements of the Radon concentration in soil air; The Lecce's area is divided into 4 sub-areas, each of them with the same geological features: subsoil structure with high/normal/low fracturing, cracking, permeability, porosity, ecc... The potential Radon risk increases with the alteration's degree of subsoil structure. Results show that the 4 Lecce's subareas are characterized by average Radon value between 1.000-2.000 Bq/m3, and that in 2 of the 4 zones, characterized by high fracturing and big permeability, the range is high, from 400 Bq/m3 to over the 60.000 Bq/m3. The distribution of anomalies isn't homogeneous in the study zone, but as Hot-Spot and these are present in all sub-areas; the greatest number is detected in areas with high fracturing and cracking and in areas with lithological changes at different permeability. The others determinants factors in these areas are those anthropogenic; in some little zones belonging to subareas there are industrial and commercial areas built removing soil and damaging and altering the subsoil structure; in this way create zones of Radon accumulation in the soil air with fast ascent of the gas to the surface, and this produce high Radon concentration indoor. In the soil around these areas, few meters from buildings, and in the indoor air the Radon concentration is higher than 60.000 Bq/m3.

  11. Factors underlying residential radon concentration: Results from Galicia, Spain

    SciTech Connect

    Barros-Dios, J.M.; Gastelu-Iturri, J.; Figueiras, A.

    2007-02-15

    Radon causes lung cancer when inhaled for prolonged periods of time. A range of factors influence residential radon concentration and this study therefore sought to ascertain which dwelling-related factors exert an influence on radon levels. A cross-sectional study was conducted from 2001 to 2003 which analyzed 983 homes of as many subjects randomly selected from the 1991 census. Sampling was carried out by district and stratified by population density to ensure that more detectors were placed in the most heavily populated areas. Radon concentration and different dwelling characteristics were measured in each of the homes selected. Bivariate and multivariate analyses were performed to ascertain which factors influenced radon concentration. The geometric mean of radon concentration was 69.5 Bq/m{sup 3}, and 21.3% of homes had concentrations above 148 Bq/m{sup 3}. Factors shown to influence radon concentration in the bivariate analysis were: age of dwelling; interior building material; exterior building material; and storey on which the detector was placed. Explanatory variables in the multivariate analysis were: age of dwelling; number of storeys; distance off floor; and interior building material. The model was significant, but the variability explained was around 10%. These results highlight the fact that the study area is an area of high radon emission and that factors other than those directly related with the characteristics of the dwelling also influence radon concentration.

  12. INDOOR AIR CONCENTRATION UNIT CONVERSIONS

    EPA Science Inventory

    Migration of volatile chemicals from the subsurface into overlying buildings is called vapor intrusion (VI). Volatile organic chemicals in contaminated soils or groundwater can emit vapors, which can migrate through subsurface soils and may enter the indoor air of overlying buil...

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

    NASA Astrophysics Data System (ADS)

    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.

  14. Natural gamma radiation map (MARNA) and indoor radon levels in Spain.

    PubMed

    Quindós Poncela, L S; Fernández, P L; Gómez Arozamena, J; Sainz, C; Fernández, J A; Suarez Mahou, E; Martin Matarranz, J L; Cascón, M C

    2004-02-01

    During the last decade, the Department of Applied and Medical Physics has been involved in the development of a radiation protection programme. In the framework of this programme, measurements of indoor radon, principally, have been carried out nationwide. Geometric mean radon concentrations of 45 Bq m(-3) in the whole country and 130 Bq m(-3) in the high natural radiation area have been estimated. On the other hand, the so-called MARNA Project is developed into the framework of an agreement subscribed between the Spanish Nuclear Safety Council (CSN) and the National Uranium (ENUSA), the first phase of which has been the elaboration of the Natural Gamma Radiation Map of Spain on the scale of 1:1,000,000 using radiometric data generated in the 30 years of the lifetime of the ancient National Uranium Exploration and Investigation Plan mainly through airborne, carborne, and by foot surveys, within the MARNA Project itself. The lowest averaged dose rate from external gamma radiation (19.3 nGyh(-1)) was found in carbonate bedrock and the highest (87.7 nGyh(-1)) was found in granite and clay bedrock. This paper summarizes the main results obtained from the measurements performed in both projects, with special interest in those concerning the correlation between the data reported in order to conclude about the potential benefit of the MARNA maps in the definition of affected areas in the country.

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

    SciTech Connect

    Hopke, P.K.

    1993-01-01

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

  16. Seasonal variation of indoor radon-222 levels in dwellings in Ramallah province and East Jerusalem suburbs, Palestine.

    PubMed

    Leghrouz, Amin A; Abu-Samreh, Mohammad M; Shehadeh, Ayah K

    2012-01-01

    This study presents the seasonal variations of indoor radon levels in dwellings located in the Ramallah province and East Jerusalem suburbs, Palestine. The measurements were performed during the summer and winter of the year 2006/2007 using CR-39 solid-state-nuclear-track detectors. The total number of investigated buildings is 75 in summer and 81 in winter. A total number of 142 dosemeters are installed in dwellings for each season for a period of almost 100 d. The radon concentration levels in summer varied from 43 to 192 Bq m(-3) for buildings in the Ramallah province and from 30 to 655 Bq m(-3) for East Jerusalem suburbs. In winter, the radon concentration levels are found to vary from 38 to 375 Bq m(-3) in the Ramallah buildings and from 35 to 984 Bq m(-3) in East Jerusalem suburbs. The obtained results for radon concentration levels in most places are found to be within the accepted international levels.

  17. Variations in radon concentration in groundwater of Kumaon Himalaya, India.

    PubMed

    Bourai, A A; Gusain, G S; Rautela, B S; Joshi, V; Prasad, G; Ramola, R C

    2012-11-01

    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 fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya, India was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq l(-1) with a mean of 50 Bq l(-1) in groundwater in different lithotectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks.

  18. Variations in radon concentration in groundwater of Kumaon Himalaya, India.

    PubMed

    Bourai, A A; Gusain, G S; Rautela, B S; Joshi, V; Prasad, G; Ramola, R C

    2012-11-01

    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 fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya, India was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq l(-1) with a mean of 50 Bq l(-1) in groundwater in different lithotectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks. PMID:22914330

  19. Developing geologic tools for finding very high indoor radon, examples from the midwestern and eastern United States

    SciTech Connect

    Gundersen, L.C.S.; Schumann, R.R.

    1995-12-31

    A three-year study of the Geologic Radon Potential of the United States was recently released by the U.S. Geological Survey (USGS) in cooperation with the U.S. Environmental Protection Agency (EPA). These geologic radon potential assessments were made using 5 types of data: 1. building architecture; 2. aerial radiometric surveys; 3. soil characteristics, 4. indoor radon; and 5. geology. These estimates predict the land`s potential to produce radon. Building upon the knowledge gained in this national study of geologic radon potential, the USGS is cooperating with the Department of Energy, Lawrence Berkeley Laboratory, and the EPA to develop a quantitative methodology for assessing the percentage of hmes (as a function of area) that exceed > 20 pCi/L in the current housing stock of the United States. In this paper, we present and contrast the geologic radon potential of two areas of the United States where indoor radon occurrences greater than 20 pCi/L are not uncommon. The Central and Southern Appalachian Highlands are south of the limit of glaciation and bedrock geologic parameters statistically account for a significant amount of the variation seen in indoor radon. Geology, soil radon, and surface gamma radiation have been compared with indoor radon and regression analyses indicate high positive correlations (R<0.5 to 0.9). In glaciated areas such as the northern Appalachian Highlands and the Central Lowlands area of the midwestern United States, the correlation of bedrock geology to indoor radon is obscured. Our most recent investigations indicate that glacial deposit morphology and radionuclide residence in the source rock can be used successfully to predict the magnitude and variation of indoor radon.

  20. Spatial variation of residential radon concentrations: The Iowa radon lung cancer study

    SciTech Connect

    Fisher, E.L.; Field, R.W.; Smith, B.J.; Lynch, C.F.; Steck, D.J.; Neuberger, J.S.

    1998-11-01

    Homeowners and researchers frequently estimate the radon concentrations in various areas of the home from a single radon measurement often performed in the home`s basement. This study describes the spatial variation of radon concentrations both between floors and between rooms on the same floor. The geometric mean basement and first floor radon concentrations for one-story homes were 13.8% and 9.0% higher, respectively, as compared to their counterparts in two-story homes. The median first floor/basement ratio of radon concentrations for one-story homes was 0.60. The median ratios between first floor/basement and second floor/basement for two-story homes were 0.51 and 0.62, respectively. The mean coefficient of variation for detectors played on the same floor was 9.5%, which was only 2.6% higher than the mean coefficient of variation found for collocated (duplicate) quality control detectors. The wide individual variations noted in radon concentrations serve as a reminder of the importance of performing multiple radon measurements in various parts of the home when estimating home radon concentrations.

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

    SciTech Connect

    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.

  2. TESTING OF INDOOR RADON REDUCTION TECHNIQUES IN CENTRAL OHIO HOUSES: PHASE 2 (WINTER 1988-1989)

    EPA Science Inventory

    The report gives results of tests of developmental indoor radon reduction techniques in nine slab-on-grade and four crawl-space houses near Dayton. Ohio. he slab-on-grade tests indicated that, when there is a good layer of aggregate under the slab, the sub-slab ventilation (SSV) ...

  3. TESTING OF INDOOR RADON REDUCTION TECHNIQUES IN BASEMENT HOUSES HAVING ADJOINING WINGS

    EPA Science Inventory

    The report gives results of tests of indoor radon reduction techniques in 12 existing Maryland houses, with the objective of determining when basement houses with adjoining wings require active soil depressurization (ASD) treatment of both wings, and when treatment of the basemen...

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

    SciTech Connect

    Tonn, Bruce Edward; Rose, Erin M.; Ternes, Mark P.

    2015-10-01

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

  5. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, July 1, 1991--June 30, 1992

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

  6. Measurement and apportionment of radon source terms for modeling indoor environments

    SciTech Connect

    Harley, N.H.

    1992-01-01

    During the present 2 1/2 year contract period, we have made significant Progress in modeling the source apportionment of indoor [sup 222]Rn and in [sup 222]Rn decay product dosimetry. Two additional areas were worked on which we believe are useful for the DOE Radon research Program. One involved an analysis of the research house data, grouping the hourly house [sup 222]Rn measurements into 2 day, 7 day and 90 day intervals to simulate the response of passive monitors. Another area requiring some attention resulted in a publication of 3 years of our indoor/outdoor measurements in a high-rise apartment. Little interest has been evinced in apartment measurements yet 20% of the US population lives in multiple-family dwellings, not in contact with the ground. These data together with a summary of all other published data on apartments showed that apartments have only about 50% greater [sup 222]Rn concentration than the measured outdoor [sup 222]Rn. Apartment dwellers generally represent a low risk group regarding [sup 222]Rn exposure. The following sections describe the main projects in some detail.

  7. Age-dependent inhalation doses to members of the public from indoor short-lived radon progeny.

    PubMed

    Brudecki, K; Li, W B; Meisenberg, O; Tschiersch, J; Hoeschen, C; Oeh, U

    2014-08-01

    The main contribution of radiation dose to the human lungs from natural exposure originates from short-lived radon progeny. In the present work, the inhalation doses from indoor short-lived radon progeny, i.e., (218)Po, (214)Pb, (214)Bi, and (214)Po, to different age groups of members of the public were calculated. In the calculations, the age-dependent systemic biokinetic models of polonium, bismuth, and lead published by the International Commission on Radiological Protection (ICRP) were adopted. In addition, the ICRP human respiratory tract and gastrointestinal tract models were applied to determine the deposition fractions in different regions of the lungs during inhalation and exhalation, and the absorption fractions of radon progeny in the alimentary tract. Based on the calculated contribution of each progeny to equivalent dose and effective dose, the dose conversion factor was estimated, taking into account the unattached fraction of aerosols, attached aerosols in the nucleation, accumulation and coarse modes, and the potential alpha energy concentration fraction in indoor air. It turned out that for each progeny, the equivalent doses to extrathoracic airways and the lungs are greater than those to other organs. The contribution of (214)Po to effective dose is much smaller compared to that of the other short-lived radon progeny and can thus be neglected in the dose assessment. In fact, 90 % of the effective dose from short-lived radon progeny arises from (214)Pb and (214)Bi, while the rest is from (218)Po. The dose conversion factors obtained in the present study are 17 and 18 mSv per working level month (WLM) for adult female and male, respectively. This compares to values ranging from 6 to 20 mSv WLM(-1) calculated by other investigators. The dose coefficients of each radon progeny calculated in the present study can be used to estimate the radiation doses for the population, especially for small children and women, in specific regions of the world

  8. Comparative analysis of radon, thoron and thoron progeny concentration measurements

    PubMed Central

    Janik, Miroslaw; Tokonami, Shinji; Kranrod, Chutima; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Hosoda, Masahiro; Mclaughlin, James; Chang, Byung-Uck; Kim, Yong Jae

    2013-01-01

    This study examined correlations between radon, thoron and thoron progeny concentrations based on surveys conducted in several different countries. For this purpose, passive detectors developed or modified by the National Institute of Radiological Sciences (NIRS) were used. Radon and thoron concentrations were measured using passive discriminative radon-thoron detectors. Thoron progeny measurements were conducted using the NIRS-modified detector, originally developed by Zhuo and Iida. Weak correlations were found between radon and thoron as well as between thoron and thoron progeny. The statistical evaluation showed that attention should be paid to the thoron equilibrium factor for calculation of thoron progeny concentrations based on thoron measurements. In addition, this evaluation indicated that radon, thoron and thoron progeny were independent parameters, so it would be difficult to estimate the concentration of one from those of the others. PMID:23297318

  9. Preseismic changes in atmospheric radon concentration and crustal strain

    NASA Astrophysics Data System (ADS)

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

    The anomalous increase in atmospheric radon concentration prior to the 1995 Kobe earthquake is compared with that in crustal strain and in other preseismic phenomena such as groundwater radon concentration, groundwater discharge rate and chloride ion concentration in groundwater. These preseismic phenomena are linked to fluctuations in crustal strain of the order of 10 -6 to 10 -8. The atmospheric radon concentration is the average or summation of radon released from a large area surrounding the monitoring station and the change can be quantitatively expressed by a power-law and log-oscillation model. These indicate that the observation of atmospheric radon is of benefit in the detection of the small anomalous preseismic crustal strain.

  10. Factors Affecting the Estimation of Indoor Radon Using Passive Activated Charcoal Canisters

    NASA Astrophysics Data System (ADS)

    Scarpitta, Salvatore Charles

    1990-01-01

    Adsorption and desorption studies of 20 activated charcoals were conducted in a monolayer and a packed bed utilizing tracer gases. Kinetic studies, using xenon-133, demonstrate the existence of a two-compartment micropore volume with entrance capillaries which together determine the response characteristics of the charcoal to external concentration gradients of tracer gases. This new two -compartment model adequately describes the adsorption and desorption dynamics of radon in the presence of water vapor. Measurements with charcoal exposed to water vapor and Rn-222 in a monolayer and packed bed for exposure intervals of 1-7 days demonstrate that the uptake rate and total quantity of adsorbed Rn-222 are highly dependent upon the amount of water adsorbed. The effect of CO_2 on radon adsorption is small in any charcoal. The measured effective diffusion coefficient of radon in a packed bed of a peat based charcoal at 15% humidity and 25^circC is 7.97 times 10^{-6} cm^2/s. Condensed water vapor in the entrance capillaries reduces the effective pore radius, increasing the diffusion half-time, both into and out of the charcoal. The amount of adsorbed water per gram of charcoal required to block the entrance capillaries varies with the charcoal type. The proposed term for this quantity is the "break-point". A two-stage diffusion barrier charcoal monitor with a long diffusion path length was developed. This design inhibits passive airflow while maintaining the amount of adsorbed water vapor in the primary charcoal adsorbent below the break-point. Water removal at the entry port allows for longer exposure times improving the integrating capability necessary for indoor exposure assessment. The long diffusion path length increases the integration time -constant for radon adsorption normally 24 hours for conventional open-faced canisters to 50 hours for the improved canister. The increased integration time-constant allows for a 7 day sample to be measured at 70% humidity and 23

  11. RADON REDUCTION AND RADON-RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK - VOLUME 1: TECHNICAL REPORT

    EPA Science Inventory

    The report gives results of radon reduction and radon-resistant construction demonstrations in New York. The existing house evaluation demonstrated radon mitigation techniques where indoor radon concentrations exceeded 4 pCi/L. Results demonstrated that sealing all accessible fou...

  12. Variation of the unattached fraction of radon progeny and its contribution to radon exposure.

    PubMed

    Guo, Lu; Zhang, Lei; Guo, Qiuju

    2016-06-01

    The unattached fraction of radon progeny is one of the most important factors for radon exposure evaluation through the dosimetric approach. To better understand its level and variation in the real environment, a series of field measurements were carried out indoors and outdoors, and radon equilibrium equivalent concentration was also measured. The dose contribution of unattached radon progeny was evaluated in addition. The results show that no clear variation trend of the unattached fraction of radon progeny is observed in an indoor or outdoor environment. The average unattached fraction of radon progeny for the indoors and outdoors are (8.7  ±  1.6)% and (9.7  ±  2.1)%, respectively. The dose contribution of unattached radon progeny to total radon exposure is some 38.8% in an indoor environment, suggesting the importance of the evaluation on unattached radon progeny. PMID:27171653

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

    SciTech Connect

    Pereira, L. A.; Hadler, J. C.; Lixandrão F, A. L.; Guedes, S.; Takizawa, R. H.

    2014-11-11

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

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

    NASA Astrophysics Data System (ADS)

    Pereira, L. A.; Hadler, J. C.; Lixandrão F., A. L.; Guedes, S.; Takizawa, R. H.

    2014-11-01

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

  15. National Weatherization Assistance Program Impact Evaluation: Impact of Exhaust-Only Ventilation on Radon and Indoor Humidity - A Field Investigation

    SciTech Connect

    Pigg, Scott

    2014-09-01

    The study described here sought to assess the impact of exhaust-only ventilation on indoor radon and humidity in single-family homes that had been treated by the Weatherization Assistance Program (WAP).

  16. Measuring radon concentration in air using a diffusion cloud chamber

    NASA Astrophysics Data System (ADS)

    Cases, R.; Ros, E.; Zúñiga, J.

    2011-09-01

    Radon concentration in air is a major concern in lung cancer studies. A traditional technique used to measure radon abundance is the charcoal canister method. We propose a novel technique using a diffusion cloud chamber. This technique is simpler and can easily be used for physics demonstrations for high school and university students.

  17. Retrospective assessment of indoor radon exposure by measurements of embedded 210Po activity in glass objects

    NASA Astrophysics Data System (ADS)

    Ramola, R. C.; Gusain, G. S.; Prasad, Ganesh

    In most of the epidemiological studies contemporary radon measurements have been used as surrogates for radon concentrations in past decades even though changes in radon levels and residence may have occurred. Short-lived radon progeny may deposit on available surfaces in dwellings thus giving rise over time to a build up of long-lived progeny. Airborne radon decay products can be deposited and implanted through alpha recoil into the glass surfaces. On glass surface, activities of 210Po may arise as a result of the decay of recoil implanted activity following the alpha decay of surface deposited 218Po or 214Po. Measurement of 210Po implanted on a household glass is a method that can be employed to retrospectively determine the historic level of radon in dwellings. This method is based on the assumption that levels of recoil implanted 210Po in the glass provide a measure of time integrated radon concentration in the environment in which the glass has been located. The surface deposited activity of the radon progenies, which then become implanted in the glass by alpha recoil, is believed to reflect past exposure to airborne activity. Such retrospective measurements on glass are valuable in estimating the human dose derived from radon during the time of exposure. In this paper an account is given of the principles and some field applications of a retrospective technique, using the alpha track detectors, CR-39 and LR-115, to measure 210Po implanted in glass surfaces (surface traps). By using this CR-LR difference technique, the cumulative radon exposure in a dwelling in past decades may be estimated. This method provides reliable radon exposure data as a support to epidemiological studies concerning the health effects of radon exposure in the living environment.

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

  19. Annual variation in the atmospheric radon concentration in Japan.

    PubMed

    Kobayashi, Yuka; Yasuoka, Yumi; Omori, Yasutaka; Nagahama, Hiroyuki; Sanada, Tetsuya; Muto, Jun; Suzuki, Toshiyuki; Homma, Yoshimi; Ihara, Hayato; Kubota, Kazuhito; Mukai, Takahiro

    2015-08-01

    Anomalous atmospheric variations in radon related to earthquakes have been observed in hourly exhaust-monitoring data from radioisotope institutes in Japan. The extraction of seismic anomalous radon variations would be greatly aided by understanding the normal pattern of variation in radon concentrations. Using atmospheric daily minimum radon concentration data from five sampling sites, we show that a sinusoidal regression curve can be fitted to the data. In addition, we identify areas where the atmospheric radon variation is significantly affected by the variation in atmospheric turbulence and the onshore-offshore pattern of Asian monsoons. Furthermore, by comparing the sinusoidal regression curve for the normal annual (seasonal) variations at the five sites to the sinusoidal regression curve for a previously published dataset of radon values at the five Japanese prefectures, we can estimate the normal annual variation pattern. By fitting sinusoidal regression curves to the previously published dataset containing sites in all Japanese prefectures, we find that 72% of the Japanese prefectures satisfy the requirements of the sinusoidal regression curve pattern. Using the normal annual variation pattern of atmospheric daily minimum radon concentration data, these prefectures are suitable areas for obtaining anomalous radon variations related to earthquakes.

  20. Contribution of (222)Rn-bearing water to indoor radon and indoor air quality assessment in hot spring hotels of Guangdong, China.

    PubMed

    Song, Gang; Wang, Xinming; Chen, Diyun; Chen, Yongheng

    2011-04-01

    This study investigates the contribution of radon ((222)Rn)-bearing water to indoor (222)Rn in thermal baths. The (222)Rn concentrations in air were monitored in the bathroom and the bedroom. Particulate matter (PM, both PM(10) and PM(2.5)) and carbon dioxide (CO(2)) were also monitored with portable analyzers. The bathrooms were supplied with hot spring water containing 66-260 kBq m(-3) of (222)Rn. The results show that the spray of hot spring water from the bath spouts is the dominant mechanism by which (222)Rn is released into the air of the bathroom, and then it diffuses into the bedroom. Average (222)Rn level was 110-410% higher in the bedrooms and 510-1200% higher in the bathrooms compared to the corresponding average levels when there was no use of hot spring water. The indoor (222)Rn levels were influenced by the (222)Rn concentrations in the hot spring water and the bathing times. The average (222)Rn transfer coefficients from water to air were 6.2 × 10(-4)-4.1 × 10(-3). The 24-h average levels of CO(2) and PM(10) in the hotel rooms were 89% and 22% higher than the present Indoor Air Quality (IAQ) standard of China. The main particle pollutant in the hotel rooms was PM(2.5). Radon and PM(10) levels in some hotel rooms were at much higher concentrations than guideline levels, and thus the potential health risks to tourists and especially to the hotel workers should be of great concern, and measures should be taken to lower inhalation exposure to these air pollutants.

  1. Consideration of measurement error when using commercial indoor radon determinations for selecting radon action levels

    USGS Publications Warehouse

    Reimer, G.M.; Szarzi, S.L.; Dolan, Michael P.

    1998-01-01

    An examination of year-long, in-home radon measurement in Colorado from commercial companies applying typical methods indicates that considerable variation in precision exists. This variation can have a substantial impact on any mitigation decisions, either voluntary or mandated by law, especially regarding property sale or exchange. Both long-term exposure (nuclear track greater than 90 days), and short-term (charcoal adsorption 4-7 days) exposure methods were used. In addition, periods of continuous monitoring with a highly calibrated alpha-scintillometer took place for accuracy calibration. The results of duplicate commercial analysis show that typical results are no better than ??25 percent with occasional outliers (up to 5 percent of all analyses) well beyond that limit. Differential seasonal measurements (winter/summer) by short-term methods provide equivalent information to single long-term measurements. Action levels in the U.S. for possible mitigation decisions should be selected so that they consider the measurement variability; specifically, they should reflect a concentration range similar to that adopted by the European Community.

  2. Human exposure to indoor radon: a survey in the region of Guarda, Portugal.

    PubMed

    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.

  3. Use of Artificial Neural Network for the Simulation of Radon Emission Concentration of Granulated Blast Furnace Slag Mortar.

    PubMed

    Jang, Hong-Seok; Xing, Shuli; Lee, Malrey; Lee, Young-Keun; So, Seung-Young

    2016-05-01

    In this study, an artificial neural networks study was carried out to predict the quantity of radon of Granulated Blast Furnace Slag (GBFS) cement mortar. A data set of a laboratory work, in which a total of 3 mortars were produced, was utilized in the Artificial Neural Networks (ANNs) study. The mortar mixture parameters were three different GBFS ratios (0%, 20%, 40%). Measurement radon of moist cured specimens was measured at 3, 10, 30, 100, 365 days by sensing technology for continuous monitoring of indoor air quality (IAQ). ANN model is constructed, trained and tested using these data. The data used in the ANN model are arranged in a format of two input parameters that cover the cement, GBFS and age of samples and, an output parameter which is concentrations of radon emission of mortar. The results showed that ANN can be an alternative approach for the predicting the radon concentration of GBFS mortar using mortar ingredients as input parameters.

  4. Use of Artificial Neural Network for the Simulation of Radon Emission Concentration of Granulated Blast Furnace Slag Mortar.

    PubMed

    Jang, Hong-Seok; Xing, Shuli; Lee, Malrey; Lee, Young-Keun; So, Seung-Young

    2016-05-01

    In this study, an artificial neural networks study was carried out to predict the quantity of radon of Granulated Blast Furnace Slag (GBFS) cement mortar. A data set of a laboratory work, in which a total of 3 mortars were produced, was utilized in the Artificial Neural Networks (ANNs) study. The mortar mixture parameters were three different GBFS ratios (0%, 20%, 40%). Measurement radon of moist cured specimens was measured at 3, 10, 30, 100, 365 days by sensing technology for continuous monitoring of indoor air quality (IAQ). ANN model is constructed, trained and tested using these data. The data used in the ANN model are arranged in a format of two input parameters that cover the cement, GBFS and age of samples and, an output parameter which is concentrations of radon emission of mortar. The results showed that ANN can be an alternative approach for the predicting the radon concentration of GBFS mortar using mortar ingredients as input parameters. PMID:27483913

  5. Metakaolin as a radon retardant from concrete.

    PubMed

    Lau, B M F; Balendran, R V; Yu, K N

    2003-01-01

    Granite aggregates are known to be the radon source in concrete. Recently, metakaolin has been introduced as a partial substitution of Portland cement to produce high strength concrete. It can effectively reduce the porosity of both the matrix and the aggregate/paste transition zone, which suggests its ability to retard radon emission from concrete aggregates. In the present work, radon exhalation rates from concrete cubes substituted with metakaolin were measured using charcoal canisters and gamma spectroscopy, and were considerably lower than those from normal concrete, by about 30%. The indoor radon concentration reduction is estimated as approximately 9 Bq m(-3) calculated using a room model, causing a 30% reduction in the indoor radon concentration and the corresponding radon dose. Therefore, metakaolin is a simple material to reduce the indoor radon concentration and the radon dose.

  6. Radon Policy in Finland, Achievements and Challenges

    SciTech Connect

    Arvela, Hannu; Maekelaeinen, Ilona; Reisbacka, Heikki

    2008-08-07

    Finland is a country of high indoor radon concentrations. Since 1980 the authority regulations, guidance, radon mapping and research work supporting decision making have been developed continuously. Clear regulations directed to citizens and authorities form the basis for radon policy. Active mapping work and measurement ordered by private home owners has resulted in 100.000 houses measured. National indoor radon data base forms a good basis for decision making, communication and research. The number of new houses provided with radon preventive constructions has increased remarkably. New radon campaigns has increased measurement and mitigation activity. Furher increasing of public awareness is the key challenge.

  7. {sup 210}Po as a long-term integrating radon indicator in the indoor environment. Final report

    SciTech Connect

    Not Available

    1992-12-31

    Exposure to radon (Rn-222) decay products in the indoor environment is suspected of being a significant lung cancer agent in many countries. But quantification of the contemporary lung cancer risk (i.e. probability) on an individual basis is not an easy task. Only past exposures are relevant and assessing individual exposures in retrospect is associated with large uncertainties, if possible at all. One way to extend the validity of contemporary measurements to past decades is to measure long-lived decay products of radon, the long-lived radon daughters. After our laboratory had exemplified the correlation between implanted Po-210 and the estimated radon exposures in six different dwellings, the US Department of Energy and the Swedish Radiation Protection Institute granted funds for a one-year study, ``{sup 210}Po as a Long-Term Integrating Radon Indicator in the Indoor Environment.`` In this report the work performed under these two contracts is reported.

  8. Potential for ion-induced nucleation of volatile organic compounds by radon decay in indoor environments

    SciTech Connect

    Daisey, J.M.

    1991-11-01

    There is considerable interest in the unattached'' fraction of radon progeny in indoor air because of its significance to the estimation of the risks of radon exposure. Because of its high mobility in air, the unattached fraction is more efficiently deposited in the respiratory tract. Variation in the diameter of the unattached'' fraction and in its diffusion coefficient can be due to clustering of other atmospheric species around the {sup 218}PoO{sub 2}{sup +} ion. The purpose of this study was to investigate the potential for the formation of clusters of vapor phase organic compounds, found in indoor air, around the {sup 218}PoO{sub 2}{sup +} ion and to determine which were most likely to form clusters. A secondary purpose was to provide a compilation of measurements of indoor organic compounds for future experiments and theoretical calculations by the radon research community. The classical charged liquid droplet theory (Thomson equation) was used to estimate the Gibbs free energy of ion-induced nucleation and to provide an indication of the indoor organic compounds most likely to undergo ion-induced nucleation. Forty-four volatile and semi-volatile organic compounds out of the more than 300 which have been reported in indoor air were investigated. Water vapor was included for comparison. The results indicate that there is a potential for the formation of clusters of organic compounds around the {sup 218}PoO{sub 2}{sup +} ion. The compounds with the greatest potential for cluster formation are the volatile oxidized hydrocarbons (e.g., n-butanol, phenol, hexanal, nonanal, benzaldehyde, the ketones and the acetates) and the semi-volatile organic compounds (pentachlorophenol, nicotine, chlordane, chlorpyrifos).

  9. Potential for ion-induced nucleation of volatile organic compounds by radon decay in indoor environments

    SciTech Connect

    Daisey, J.M.

    1991-11-01

    There is considerable interest in the ``unattached`` fraction of radon progeny in indoor air because of its significance to the estimation of the risks of radon exposure. Because of its high mobility in air, the unattached fraction is more efficiently deposited in the respiratory tract. Variation in the diameter of the ``unattached`` fraction and in its diffusion coefficient can be due to clustering of other atmospheric species around the {sup 218}PoO{sub 2}{sup +} ion. The purpose of this study was to investigate the potential for the formation of clusters of vapor phase organic compounds, found in indoor air, around the {sup 218}PoO{sub 2}{sup +} ion and to determine which were most likely to form clusters. A secondary purpose was to provide a compilation of measurements of indoor organic compounds for future experiments and theoretical calculations by the radon research community. The classical charged liquid droplet theory (Thomson equation) was used to estimate the Gibbs free energy of ion-induced nucleation and to provide an indication of the indoor organic compounds most likely to undergo ion-induced nucleation. Forty-four volatile and semi-volatile organic compounds out of the more than 300 which have been reported in indoor air were investigated. Water vapor was included for comparison. The results indicate that there is a potential for the formation of clusters of organic compounds around the {sup 218}PoO{sub 2}{sup +} ion. The compounds with the greatest potential for cluster formation are the volatile oxidized hydrocarbons (e.g., n-butanol, phenol, hexanal, nonanal, benzaldehyde, the ketones and the acetates) and the semi-volatile organic compounds (pentachlorophenol, nicotine, chlordane, chlorpyrifos).

  10. RADON GENERATION AND TRANSPORT THROUGH CONCRETE FOUNDATIONS

    EPA Science Inventory

    The report gives results of an examination of radon generation and transport through Florida residential concretes for their contribution to indoor radon concentrations. Radium concentrations in the 11 concretes tested were all <2.5 pCi/g and radon emanation coefficients were all...

  11. An assessment of ecological and case-control methods for estimating lung cancer risk due to indoor radon

    SciTech Connect

    Stidley, C.A.; Samet, J.M.

    1992-12-31

    Studies of underground miners indicate that indoor radon is an important cause of lung cancer. This finding has raised concern that exposure to radon also causes lung cancer in the general population. Epidemiological studies, including both case-control and ecological approaches, have directly addressed the risks of indoor residential radon; many more case-control studies are in progress. Ecological studies that associate lung-cancer rates with typical indoor radon levels in various geographic areas have not consistently shown positive associations. The results of purportedly negative ecological studies have been used as a basis for questioning the hazards of indoor radon exposure. Because of potentially serious methodologic flaws for testing hypotheses, we examined the ecological method as a tool for assessing lung-cancer risk from indoor radon exposure. We developed a simulation approach that utilizes the Environmental Protection Agency (EPA) radon survey data to assign exposures to individuals within counties. Using the computer-generated data, we compared risk estimates obtained by ecological regression methods with those obtained from other regression methods and with the {open_quotes}true{close_quotes} risks used to generate the data. For many of these simulations, the ecological models, while fitting the summary data well, gave risk estimates that differed considerably from the true risks. For some models, the risk estimates were negatively correlated with exposure, although the assumed relationship was positive. Attempts to improve the ecological models by adding smoking variables, including interaction terms, did not always improve the estimates of risk, which are easily affected by model misspecification. Because exposure situations used in the simulations are realistic, our results show that ecological methods may not accurately estimate the lung-cancer risk associated with indoor radon exposure.

  12. Use of linear regression models to determine influence factors on the concentration levels of radon in occupied houses

    NASA Astrophysics Data System (ADS)

    Buermeyer, Jonas; Gundlach, Matthias; Grund, Anna-Lisa; Grimm, Volker; Spizyn, Alexander; Breckow, Joachim

    2016-09-01

    This work is part of the analysis of the effects of constructional energy-saving measures to radon concentration levels in dwellings performed on behalf of the German Federal Office for Radiation Protection. In parallel to radon measurements for five buildings, both meteorological data outside the buildings and the indoor climate factors were recorded. In order to access effects of inhabited buildings, the amount of carbon dioxide (CO2) was measured. For a statistical linear regression model, the data of one object was chosen as an example. Three dummy variables were extracted from the process of the CO2 concentration to provide information on the usage and ventilation of the room. The analysis revealed a highly autoregressive model for the radon concentration with additional influence by the natural environmental factors. The autoregression implies a strong dependency on a radon source since it reflects a backward dependency in time. At this point of the investigation, it cannot be determined whether the influence by outside factors affects the source of radon or the habitant’s ventilation behavior resulting in variation of the occurring concentration levels. In any case, the regression analysis might provide further information that would help to distinguish these effects. In the next step, the influence factors will be weighted according to their impact on the concentration levels. This might lead to a model that enables the prediction of radon concentration levels based on the measurement of CO2 in combination with environmental parameters, as well as the development of advices for ventilation.

  13. Measurements of radon concentrations in the lunar atmosphere

    NASA Technical Reports Server (NTRS)

    Brodzinski, R. L.; Jackson, P. O.; Langford, J. C.

    1977-01-01

    The radon concentrations in the lunar atmosphere were determined by measuring the Po-210 progeny activity in artifacts returned from the moon. Experiments performed on a section of the polished aluminum strut from Surveyor 3 and data obtained from the Apollo 16 Cosmic Ray Detector Experiment Teflon thermal shield are compared with other values of the lunar radon concentration obtained at different times and different locations and by various techniques. Possible sources and release mechanisms compatible with all of the data are discussed. An experimental procedure to determine the relative retention coefficients of various types of material for radon progeny in a simulated lunar environment is described. The results of several experiments are given, and their effect on lunar radon progeny measurements is discussed. An analytical procedure is given for the analysis of a Teflon matrix for trace constituents.

  14. The influence of thoron on instruments measuring radon activity concentration.

    PubMed

    Michielsen, N; Bondiguel, S

    2015-11-01

    Thoron, the isotope 220 of radon, is a radionuclide whose concentration may influence the measurement of the activity concentration of (222)Rn in the air. If in the case of continuous and active sampling measuring instruments, using a pump for example, the influence of thoron on radon measurement is obvious and is taken into account in the apparatus, it is often assumed that in the case of a passive sampling, by diffusion through a filter for example, this thoron influence is negligible. This is due to the very short radioactive half-life of thoron, 55.6 s (3.82 d for (222)Rn), and the assumption that the diffusion time of thoron in the detection chamber is long enough beside that of the thoron half-life. The objective of this study is to check whether this assumption is true or not for different kinds of commercial electronic apparatus used to measure radon activity concentration from soil to dwellings. First of all, the devices were calibrated in activity concentration of radon, and then they were exposed to a controlled thoron atmosphere. The experiments concerning the thoron aimed to investigate the sensitivity to thoron in the radon measuring mode of the apparatus. Results of these experiments show that all devices have a very quick answer to thoron atmosphere, even though the sensitivities vary from one instrument to another. Results clearly show that this influence on radon measurement due to the thoron is observed also after the exposition because of the decay of (212)Pb and its progenies. In conclusion, the sensitivity to thoron in the radon measuring mode depends strongly on the type of instruments. The results of the present investigation show that for some apparatus, the influence of thoron cannot be disregarded especially when measuring radon in soil.

  15. New Methods of Energy Efficient Radon Mitigation

    SciTech Connect

    Fisk, W.J.; Prill, R.J.; Wooley, J.; Bonnefous, Y.C.; Gadgil, A.J.; Riley, W.J.

    1994-05-01

    Two new radon mitigation techniques are introduced and their evaluation in a field study complemented by numerical model predictions is described. Based on numerical predictions, installation of a sub gravel membrane at the study site resulted in a factor of two reduction in indoor radon concentrations. Experimental data indicated that installation of 'short-circuit' pipes extending between the subslab gravel and outdoors, caused an additional factor of two decrease in the radon concentration. Consequently, the combination of these two passive radon mitigation features, called the membrane and short-circuit (MASC) technique, was associated with a factor of four reduction in indoor radon concentration. The energy-efficient active radon mitigation method, called efficient active subslab pressurization (EASP), required only 20% of the fan energy of conventional active subslab depressurization and reduced the indoor radon concentration by approximately a factor of 15, including the numerically-predicted impact of the sub-gravel membrane.

  16. New methods of energy efficient radon mitigation

    SciTech Connect

    Fisk, W.J.; Wooley, J.; Gadgil, A.J.

    1995-05-01

    Two new radon mitigation techniques are introduced and their evaluation in a field study complemented by numerical model predictions is described. Based on numerical predictions, installation of a sub gravel membrane at the study site resulted in a factor of 2 reduction in indoor radon concentrations. Experimental data indicated that installation of {open_quotes}short-circuit{close_quotes} pipes extending between the subslab gravel and outdoors caused an additional factor of 2 decrease in the radon concentration. Consequently, the combination of these two passive radon mitigation features, called the membrane and short-circuit (MASC) technique, was associated with a factor of 4 reduction in indoor radon concentration. The energy-efficient active radon mitigation method, called efficient active subslab pressurization (EASP), required only 20% of the fan energy of conventional active subslab depressurization and reduced the indoor radon concentration by approximately a factor of 15, including the numerically-predicted impact of the sub-gravel membrane.

  17. Predictions of lung cancer based on county averages for indoor radon versus the historic incidence of regional lung cancer

    SciTech Connect

    Mose, D.G.; Chrosniak, C.E.; Mushrush, G.W. . Center for Basic and Applied Science)

    1992-01-01

    After a decade of effort to determine the health risk associated with indoor radon, the efforts of the US Environmental Protection Agency have prevailed in the US, and 4 pCi/1 is commonly used as an Action Level. Proposals by other groups supporting lower or higher Action Levels have failed, largely due to paucity of information supporting any particular level of indoor radon. The authors' studies have compared indoor radon for zip code and county size areas with parameters such as geology, precipitation and home construction. Their attempts to verify the relative levels of lung cancer using US-EPA estimates of radon-vs-cancer have not been supportive of the EPA risk estimates. In general, when they compare the number of lung cancer cases in particular geological or geographical areas with the indoor radon levels in that area, they find the EPA predicted number of lung cancer cases to exceed the total number of lung cancer cases from all causes. Comparisons show a correlation between the incidence of lung cancer and indoor radon, but the level of risk is about 1/10 that proposed by the US-EPA. Evidently the assumptions used in their studies are flawed. Even though they find lower risk estimates using many counties in several states, fundamental flaws must be present in this type of investigation. Care must be taken in presenting health risks to the general population in cases, such as in indoor radon, where field data do not support risk estimates obtained by other means.

  18. Dosimetry of radon and thoron exposures: Implications for risks from indoor exposure

    SciTech Connect

    James, A.C.

    1992-12-31

    Current estimates of lung-cancer risks due to the inhalation of radon and its progeny in homes are based on extrapolations of excess mortality observed in populations of underground miners. To project lung-cancer risk to the general public it is necessary to account for any effects that different exposure conditions may have on doses received by critical target cells in the respiratory tract. This paper summarizes the results of a review of aerosol parameters, physiological and biological factors, and cells at risk that are involved in comparing doses between mine and indoor environments. The dose received by sensitive cells in the bronchi from exposure to a given amount of potential alpha-energy (commonly given the unit Working Level Month, WLM) is found to be approximately 20% lower indoors that for healthy underground miners. However, this estimate of the ratio of dose per unit exposure in homes compared to that in mines (termed the {open_quotes}K-factor{close_quotes}) is sensitive to the assumed hygroscopic properties of radon-progeny aerosols. The estimate of K varies from about 0.9, if radon-progeny aerosol particles are assumed not to grow hygroscopically in the respiratory tract, to about 0.6 if the ambient particles are assumed to double in size by hygroscopic growth.

  19. Radon concentration in soil gas and radon exhalation rate at the Ravne Fault in NW Slovenia

    NASA Astrophysics Data System (ADS)

    Vaupotič, J.; Gregorič, A.; Kobal, I.; Žvab, P.; Kozak, K.; Mazur, J.; Kochowska, E.; Grzä Dziel, D.

    2010-04-01

    The Ravne tectonic fault in north-west (NW) Slovenia is one of the faults in this region, responsible for the elevated seismic activity at the Italian-Slovene border. Five measurement profiles were fixed in the vicinity of the Ravne fault, four of them were perpendicular and one parallel to the fault. At 18 points along these profiles the following measurements have been carried out: radon activity concentration in soil gas, radon exhalation rate from ground, soil permeability and gamma dose rate. The radon measurements were carried out using the AlphaGuard equipment, and GammaTracer was applied for gamma dose rate measurements. The ranges of the obtained results are as follows: 0.9-32.9 kBq m-3 for radon concentration (CRn), 1.1-41.9 mBq m-2 s-1 for radon exhalation rate (ERn), 0.5-7.4×10-13 m2 for soil permeability, and 86-138 nSv h-1 for gamma dose rate. The concentrations of 222Rn in soil gas were found to be lower than the average for Slovenia. Because the deformation zones differ not only in the direction perpendicular to the fault but also along it, the behaviour of either CRn or ERn at different profiles differ markedly. The study is planned to be continued with measurements being carried out at a number of additional points.

  20. Radon concentrations in three underground lignite mines in Turkey.

    PubMed

    Cile, S; Altinsoy, N; Celebi, N

    2010-01-01

    Monitoring of radon in underground mines is important in order to assess the radiological hazards to occupational workers. Radon concentration levels in three underground lignite mines (Tunçbilek, Omerler and Eynez) of Turkey were obtained in this study. For this reason, atmospheric radon level measurements were carried out in mines using CR-39 track detectors. Chemical etching of the detector tracks and subsequent counting were performed at Cekmece Nuclear Research and Training Center. The obtained results were evaluated according to the International Commission of Radiation Protection and the Turkish Atomic Energy Authority whose radon action levels for workplaces are 500-1500 and 1000 Bq(-3), respectively. The radon gas concentrations in the lignite mines were determined to be between 50 +/- 7 and 587 +/- 16 Bq m(-3). The results obtained in these experiments are far under the action levels. The computed radon doses for the mine workers of Tunçbilek, Omerler and Eynez lignite mines are 1.23, 2.44 and 1.47 mSv y(-1), respectively.

  1. A follow-up study on indoor 222Rn, 220Rn their decay product concentrations in a mineralised zone of Himachal Pradesh, India.

    PubMed

    Bajwa, B S; Singh, Parminder; Singh, Prabhjot; Saini, Komal; Singh, Surinder; Sahoo, B K; Sapra, B K

    2016-03-01

    A follow-up study was taken up in a mineralised zone situated in Hamirpur district, Himachal Pradesh, India, to investigate high values of radon concentrations reported in past studies as well to update the old radon data based on bare SSNTD technique. In the present investigation, the concentrations of indoor radon, thoron and their decay products have been measured using the newly developed radon/thoron discriminating diffusion chamber with single entry face, direct radon and thoron progeny sensors (DRPS/DTPS), respectively. The measurements have been carried out in 75 dwellings of 14 different villages where the previous studies were carried out using bare SSNTD technique. It was observed that high values of earlier reported radon concentrations were mainly due to thoron interference in the Solid State Nuclear Track Detector (LR-115 type II) exposed in bare mode. Now, the average concentration values and the estimated annual inhalation dose in these villages have been found to be within the reference level as recommended by the ICRP. The annual average indoor radon and thoron concentrations observed in these dwellings have been found to vary from 44±12 to 157±73 Bq m(-3) and 44±11 to 240±125 Bq m(-3), respectively. The equilibrium equivalent concentrations of radon and thoron decay products have been observed to be in the range of 10 to 63 and 1 to 5 Bq m(-3), respectively. PMID:26184660

  2. Longitudinal variations in indoor VOC concentrations after moving into new apartments and indoor source characterization.

    PubMed

    Shin, Seung-Ho; Jo, Wan-Kuen

    2013-06-01

    This study examined the indoor concentrations of a wide range of volatile organic compounds (VOCs) in currently built new apartments every month over a 24-month period and the source characteristics of indoor VOCs. The indoor total VOC (TVOC) concentrations exhibited a decreasing tendency over the 24-month follow-up period. Similar to TVOCs, the median indoor concentrations of 33 of 40 individual VOCs (all except for naphthalene and six halogenated VOCs) revealed decreasing tendencies. In contrast, the indoor concentrations of the six halogenated VOCs did not reveal any definite trend with time. Moreover, the indoor concentrations of those halogenated VOCs were similar to the outdoor concentrations, suggesting the absence of any notable indoor sources of halogenated VOCs. For naphthalene (NT), the indoor concentrations were significantly higher than the outdoor concentrations, suggesting the presence of indoor NT source(s). The floor/wall coverings (39 %) were the most influential indoor source of indoor VOCs, followed by household cleaning products (32 %), wood paneling/furniture (17 %), paints (7 %), and moth repellents (5 %).

  3. Mineralogy and aeroradioactivity as indicators of radon hazard zones

    SciTech Connect

    Sullivan, K.T.; Mose, D.G.; Mushrush, G.W.

    1997-08-01

    The concentrations of indoor radon in the basements of homes located in southern Maryland average 1.3 times the first-floor radon concentrations. Particular geological units tend to be associated with higher indoor radon. In the study area, homes underlain by phyllite are generally above 4 pCi/L (the US Environmental Protection Agency action level). Comparative studies between indoor radon and total-gamma aeroradioactivity show that aeroradioactivity can be accurately used to estimate community radon hazards. When combined, geology and aeroradioactivity can be used to identify problem homes.

  4. Seasonal variation of radon concentrations in UK homes.

    PubMed

    Miles, J C H; Howarth, C B; Hunter, N

    2012-09-01

    The patterns of seasonal variation of radon concentrations were measured in 91 homes in five regions of the UK over a period of two years. The results showed that there was no significant difference between the regions in the pattern or magnitude of seasonal variation in radon concentrations. The arithmetic mean variation was found to be close to that found previously in the UK national survey. Differences in the pattern between the two years of the study were not significant. Two-thirds of homes in the study followed the expected pattern of high radon in the winter and low radon in the summer. Most of the rest showed little seasonal variation, and a few showed a reversed seasonal pattern. The study does not provide any clear evidence for the recorded house characteristics having an effect on the seasonal variation in radon concentrations in UK homes, though the statistical power for determining such effects is limited in this study. The magnitude of the seasonal variation varied widely between homes. Analysis of the individual results from the homes showed that because of the wide variation in the amount of seasonal variation, applying seasonal correction factors to the results of three-month measurements can yield only relatively small improvements in the accuracy of estimates of annual mean concentrations.

  5. Transport of radon from soil into residences

    SciTech Connect

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

    1984-02-01

    To develop effective monitoring and control programs for indoor radon it is important to understand the causes of the broad range of concentrations that has been observed. Measurements of indoor radon concentration and air-exchange rate in dwellings in several countries indicate that this variability arises largely from differences among structures in the rate of radon entry. Recent evidence further suggests that the major source of indoor radon in many circumstances is the soil adjacent to the building foundation and that pressure-driven flow, rather than molecular diffusion, is the dominant transport process by which radon enters the buildings. Key factors affecting radon transport from soil are radon production in soil, flow-inducing mechanisms, soil permeability, and building substructure type. 24 references, 1 figure.

  6. Validity of the Kusnetz method for measuring radon progeny concentration

    SciTech Connect

    Duport, P.

    1998-12-31

    The standard Kusnetz and Rolle methods currently used to measure the concentration of potential alpha energy due to the presence of radon progeny were designed at a time when ventilation conditions were very different than in current mines. This report reviews those methods and evaluated whether they are still reliable when the residency time of air underground is very short compared to the half-life of short-lived radon progeny, and in particular, under the new ventilation conditions that exist in Saskatchewan uranium mines. The uncertainty in measurements of potential alpha energy concentration is evaluated using Monte Carlo simulation.

  7. Towards a Brazilian radon map: consortium radon Brazil.

    PubMed

    Silva, N C; Bossew, P; Ferreira Filho, A L; Campos, T F C; Pereira, A J S C; Yoshimura, E M; Veiga, L H S; Campos, M P; Rocha, Z; Paschuk, S A; Bonotto, D M

    2014-07-01

    Recently, the idea of generating radon map of Brazil has emerged. First attempts of coordinating radon surveys--carried out by different groups across the country--and initial discussions on how to proceed on a larger scale were made at the First Brazilian Radon Seminary, Natal, September 2012. Conventionally, it is believed that indoor radon is no major problem in Brazil, because the overall benign climate usually allows high ventilation rates. Nevertheless, scattered measurements have shown that moderately high indoor radon concentrations (up to a few hundred Bq m⁻³) do occur regionally. Brazilian geology is very diverse and there are regions where an elevated geogenic radon potential exists or is expected to exist. Therefore, a Brazilian Radon Survey is expected to be a challenge, although it appears an important issue, given the rising concern of the public about the quality of its environment.

  8. Radon

    MedlinePlus

    ... with elevated radon underwent changes to reduce radon pollution. 1 How Can Radon Be Detected? The only ... Association Applauds EPA’s Update to Cross-State Air Pollution Rule News: New Truck Efficiency Standards Expected to ...

  9. A novel algorithm for quick and continuous tracing the change of radon concentration in environment

    NASA Astrophysics Data System (ADS)

    Tan, Yanliang; Xiao, Detao

    2011-04-01

    Several measurements of the radon concentration are performed by RAD7 in the University of South China. We find that 30-40 min is needed for RAD7 for tracing the concentration of the standard radon chamber. There are two reasons. The first is that the sufficient time of air cycle is needed for the radon concentration in internal cell of RAD7 equal to that of the environment; and the second is that the sufficient decay time is needed for the 218Po concentration in internal cell of RAD7 equal to that of the radon. We used a zeroth order approximation to describe the evolution of the environment radon concentration, and obtained a novel algorithm for quick and continuous tracing the change of radon concentration. The corrected radon concentration obtained through this method is in good agreement with the reference value. This method can be applied to develop and improve the instruments for tracing the change of radon concentration quickly.

  10. Calculating flux to predict future cave radon concentrations.

    PubMed

    Rowberry, Matt D; Martí, Xavi; Frontera, Carlos; Van De Wiel, Marco J; Briestenský, Miloš

    2016-06-01

    Cave radon concentration measurements reflect the outcome of a perpetual competition which pitches flux against ventilation and radioactive decay. The mass balance equations used to model changes in radon concentration through time routinely treat flux as a constant. This mathematical simplification is acceptable as a first order approximation despite the fact that it sidesteps an intrinsic geological problem: the majority of radon entering a cavity is exhaled as a result of advection along crustal discontinuities whose motions are inhomogeneous in both time and space. In this paper the dynamic nature of flux is investigated and the results are used to predict cave radon concentration for successive iterations. The first part of our numerical modelling procedure focuses on calculating cave air flow velocity while the second part isolates flux in a mass balance equation to simulate real time dependence among the variables. It is then possible to use this information to deliver an expression for computing cave radon concentration for successive iterations. The dynamic variables in the numerical model are represented by the outer temperature, the inner temperature, and the radon concentration while the static variables are represented by the radioactive decay constant and a range of parameters related to geometry of the cavity. Input data were recorded at Driny Cave in the Little Carpathians Mountains of western Slovakia. Here the cave passages have developed along splays of the NE-SW striking Smolenice Fault and a series of transverse faults striking NW-SE. Independent experimental observations of fault slip are provided by three permanently installed mechanical extensometers. Our numerical modelling has revealed four important flux anomalies between January 2010 and August 2011. Each of these flux anomalies was preceded by conspicuous fault slip anomalies. The mathematical procedure outlined in this paper will help to improve our understanding of radon migration

  11. Indoor radon levels in workplaces of Adapazarı, north-western Turkey

    NASA Astrophysics Data System (ADS)

    Kapdan, Enis; Altinsoy, Nesrin

    2014-02-01

    The main objective of this study is to assess the health hazards due to radon gas accumulation and to compare the concentrations in different kinds of workplaces, in the city of Adapazarı, one of the most important industrial cities of Turkey. For this purpose, radon activity concentration measurements were carried out in schools, factories, offices and outdoors using CR-39 solid state nuclear track detectors (SSNTD). Results show that the mean radon activity concentrations (RAC) in schools, offices and factories were found to be 66, 76 and 27 Bq/m3, respectively, with an outdoor concentration of 14 Bq/m3. The average concentrations were found to decrease as follows for different types of industries: automotive > electronic > metal > textile. Because the maximum measured radon concentrations are 151 Bq/m3 in the schools, 173 Bq/m3 in the offices and 52 Bq/m3 in the factories, the limits of ICRP are not exceeded in any of the buildings in the region. In addition, the estimated mean annual effective doses to the people in the workplace, students, office workers and factory workers have been calculated as 0.27, 0.63 and 0.20 mSv/y, respectively for the region.

  12. [Radon and domestic exposure].

    PubMed

    Melloni, B; Vergnenègre, A; Lagrange, P; Bonnaud, F

    2000-12-01

    Radon is a noble gas derived from the decay of radium, which itself is a decay product of uranium. The decay products of radon can collect electrostatically on dust particles in the air and, if these particles are inhaled and attach to bronchial epithelium, produce a high local radiation dose. Alpha particles can induce DNA double-strand breaks and the development of cancer. A causal relation between lung cancer and radon exposure and its progeny has been demonstrated in epidemiological studies of miners. Radon exposure became a public health issue almost 15 years ago. Most radon exposure occurs indoors, predominantly in the home. There is however, a wide range of radon concentration values in different countries. The highest level occurs in areas with granite and permeable soils. The risk for smoking, the leading cause of lung cancer, is far greater than for radon, the second leading cause. The estimates obtained from case-control studies of indoor radon are very contradictory. Scientific knowledge of effects of low levels of exposure to radon and the role of cigarette smoking, as a combined factor, must be studied. Smoking and radon probably interact in a multiplicative fashion.

  13. Radon mitigation of groundwater at a commercial fish hatchery

    SciTech Connect

    Kitto, M.; Kunz, C.; McNulty, C.; Kuhland, M.

    1995-12-31

    Groundwater radon levels of 83 Bq/L (2240 pCi/L) generated indoor radon levels >3300 Bq/m{sup 3} (89 pCi/L) at a commercial fish hatchery. Passive and active mitigation strategies to reduce the waterborne radon levels included a packed column, a waterfall through perforated grates, surface aeration, and bottom bubblers. Though waterborne concentrations were reduced up to 83% using a combination of mitigation procedures, a comparable reduction in indoor radon concentrations was not observed. Measurements by two continuous radon detectors agreed with those from grab flasks. A diurnal cycle showed that indoor radon levels peaked in early afternoon, probably as a result of warmer air being dissolved in the water during mitigation. Reduction of indoor radon levels below 148 Bq/m{sup 3} (4 Ci/L) was achieved by direct air ventilation at high flow rates.

  14. An automated, semi-continuous system for measuring indoor radon progeny activity-weighted size distributions, d sub p : 0. 5--500 nm

    SciTech Connect

    Li, Chih-Shan; Hopke, P.K.; Ramamurthi, M.

    1990-05-01

    A system for the detection and measurement of indoor radon progeny activity-weighted size distributions (particle size, d{sub p} > 0.5 nm) and concentration levels has been developed. The system is microcomputer-controlled and involves a combination of multiple wire screen (Graded Screen Array) sampler-detector units operated in parallel. The radioactivity sampled in these units permits the estimation of the radon progeny activity-weighted size distributions and concentration levels on a semi-continuous basis. This paper presents details of the system and describes various stages in the development of the system. Results of field measurements in a residential environment are presented to illustrate the resolution, sensitivity and capabilities of the measurement system. 16 refs., 4 figs., 1 tab.

  15. RE-ENTRAINMENT AND DISPERSION OF EXHAUSTS FROM INDOOR RADON REDUCTION SYSTEMS: ANALYSIS OF TRACER GAS DATA

    EPA Science Inventory

    Tracer gas studies were conducted around four model houses in a wind tunnel, and around one house in the field, to quantify re-entrainment and dispersion of exhaust gases released from residential indoor radon reduction systems. Re-entrainment tests in the field suggest that acti...

  16. Variability of radon and thoron equilibrium factors in indoor environment of Garhwal Himalaya.

    PubMed

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Kandari, Tushar; Gusain, G S; Mishra, Rosaline; Ramola, R C

    2016-01-01

    The measurements of radon, thoron and their progeny concentrations have been carried out in the dwellings of Uttarkashi and Tehri districts of Garhwal Himalaya, India using LR-115 detector based pin-hole dosimeter and DRPS/DTPS techniques. The equilibrium factors for radon, thoron and their progeny were calculated by using the values measured with these techniques. The average values of equilibrium factor between radon and its progeny have been found to be 0.44, 0.39, 0.39 and 0.28 for rainy, autumn, winter and summer seasons, respectively. For thoron and its progeny, the average values of equilibrium factor have been found to be 0.04, 0.04, 0.04 and 0.03 for rainy, autumn, winter and summer seasons, respectively. The equilibrium factor between radon and its progeny has been found to be dependent on the seasonal changes. However, the equilibrium factor for thoron and progeny has been found to be same for rainy, autumn and winter seasons but slightly different for summer season. The annual average equilibrium factors for radon and thoron have been found to vary from 0.23 to 0.80 with an average of 0.42 and from 0.01 to 0.29 with an average of 0.07, respectively. The detailed discussion of the measurement techniques and the explanation for the results obtained is given in the paper. PMID:26520684

  17. Variability of radon and thoron equilibrium factors in indoor environment of Garhwal Himalaya.

    PubMed

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Kandari, Tushar; Gusain, G S; Mishra, Rosaline; Ramola, R C

    2016-01-01

    The measurements of radon, thoron and their progeny concentrations have been carried out in the dwellings of Uttarkashi and Tehri districts of Garhwal Himalaya, India using LR-115 detector based pin-hole dosimeter and DRPS/DTPS techniques. The equilibrium factors for radon, thoron and their progeny were calculated by using the values measured with these techniques. The average values of equilibrium factor between radon and its progeny have been found to be 0.44, 0.39, 0.39 and 0.28 for rainy, autumn, winter and summer seasons, respectively. For thoron and its progeny, the average values of equilibrium factor have been found to be 0.04, 0.04, 0.04 and 0.03 for rainy, autumn, winter and summer seasons, respectively. The equilibrium factor between radon and its progeny has been found to be dependent on the seasonal changes. However, the equilibrium factor for thoron and progeny has been found to be same for rainy, autumn and winter seasons but slightly different for summer season. The annual average equilibrium factors for radon and thoron have been found to vary from 0.23 to 0.80 with an average of 0.42 and from 0.01 to 0.29 with an average of 0.07, respectively. The detailed discussion of the measurement techniques and the explanation for the results obtained is given in the paper.

  18. Geological factors controlling radon hazardous concentration in groundwater

    NASA Astrophysics Data System (ADS)

    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

  19. Study of a cave's air exchange pattern based on radon concentration and the time dependence of radon concentration in Pál-völgy Cave (Budapest, Hungary)

    NASA Astrophysics Data System (ADS)

    Nagy, H. E.; Horvath, A.; Jordan, Gy.; Szabo, Cs.; Kiss, A.

    2012-04-01

    A long-term (one year and a half), high resolution, with an integration time of one hour, radon concentration monitoring was carried out in Pál-völgy Cave (Budapest, Hungary). Our major goal was to determine the time dependence of radon concentration in the cave and to understand the exchange pattern of the cave air with the outdoor air based on radon concentrations, and to determine the factors that affect the radon concentration in the cave air. Pál-völgy Cave is situated in the Buda Hills, which is the NE part of the Transdanubian Central Range. The wall rock of the cave is dominantly Eocene Szépvölgy Limestone Formation. Above the limestone Eocene Buda Marl and Oligocene Tard Clay are deposited. A huge multiphase hydrothermal cave system developed in the Szépvölgy Limestone and partially in the Buda Marl resulted in a long-term complex paleokarstic evolution from the Late Eocene to the Quaternary. The radon concentration in the cave air was measured continuously by an AlphaGuard radon monitor, and meteorological parameters outside the cave were also collected simultaneously. The arithmetic mean of the annual radon concentration was 1.9 kBq/m3 and the radon concentration varied between 104-7,776 Bq/m3. In addition, the results indicate a clear seasonal variability of radon concentration in the cave air: in winter the radon concentration fluctuates around a low mean value of 253 Bq/m3, in summer it oscillates around a high mean value of 5,504 Bq/m3, whereas in spring and autumn the radon level varies between the winter and summer values. The summer to winter radon concentration ratio (radon concentration in summer/radon concentration in winter) was high, 21.8. The outside air temperature showed the strongest correlation with the radon concentration in the cave, Pierson's linear correlation coefficient is 0.76. If the outdoor air temperature is lower than the cave air temperature (12 °C), especially in autumn and winter the air flows from outside into the

  20. Measurement of potential alpha energy exposure and potential alpha energy concentration and estimating radiation dose of radon in Sari city in the north region of Iran.

    PubMed

    Rahimi, Seyed Ali; Nikpour, Behzad

    2014-12-01

    In dwellings in Sari city in the northern region of Iran, the potential alpha energy exposure (PAEE) and potential alpha energy concentration (PAEC) have been measured and the radiation dose due to radon and its progenies has been estimated. In this study, the dosemeters DOSEman and SARAD GmbH (Germany), which are sensitive to alpha particles, were used. The population of the city of Sari is 495,369 people and the density of population is 116.5 people per km(2). A percentage of the total household population of Sari in areas of geographically different samples was selected. The PAEE, PAEC and radon concentration in four different seasons in a year in homes for sampling were measured. The mean PAEE due to indoor radon in homes of four cities in Sari city was estimated to be 28.23 Bq m(-3) and the mean PAEC was estimated to be 27.11 Bq m(-3). Also the mean indoor radon level was found to be 29.95 Bq m(-3). The annual dose equivalent is ∼0.0151 μSv y(-1). Measurement results show that the average PAEE, PAEC and radon concentration are higher in winter than in other seasons. This difference could be due to stillness and lack of air movement indoors in winter.

  1. Measurement and apportionment of radon source terms for modeling indoor environments. Final progress report, March 1990--August 1992

    SciTech Connect

    Harley, N.H.

    1992-12-31

    During the present 2 1/2 year contract period, we have made significant Progress in modeling the source apportionment of indoor {sup 222}Rn and in {sup 222}Rn decay product dosimetry. Two additional areas were worked on which we believe are useful for the DOE Radon research Program. One involved an analysis of the research house data, grouping the hourly house {sup 222}Rn measurements into 2 day, 7 day and 90 day intervals to simulate the response of passive monitors. Another area requiring some attention resulted in a publication of 3 years of our indoor/outdoor measurements in a high-rise apartment. Little interest has been evinced in apartment measurements yet 20% of the US population lives in multiple-family dwellings, not in contact with the ground. These data together with a summary of all other published data on apartments showed that apartments have only about 50% greater {sup 222}Rn concentration than the measured outdoor {sup 222}Rn. Apartment dwellers generally represent a low risk group regarding {sup 222}Rn exposure. The following sections describe the main projects in some detail.

  2. Potential for ion-induced nucleation of volatile organic compounds by radon decay in indoor environments

    SciTech Connect

    Daisey, J.M. ); Hopke, P.K. )

    1993-07-01

    The theoretical potential for the formation of clusters of vapor-phase organic compounds found in indoor air around the [sup 218]PoO[sub x][sup +] ion was investigated as well as which compounds were most likely to form clusters. A compilation of measurements of indoor organic compounds has been made for future experiments and theoretical calculations by the radon research community. Forty-four volatile and semivolatile organic compounds out of the more than 300 that have been reported in indoor air were investigated. Water vapor was included for comparison. The results indicate that there is a potential for the formation of clusters of organic compounds around the [sup 218]PoO[sub x][sup +] ion. The compounds with the greatest potential for cluster formation are the volatile oxidized hydrocarbons (e.g., n-butanol, phenol, hexanal, nonanal, benzaldehyde, the ketones, and the acetates) and the semivolatile organic compounds (pentachlorophenol, nicotine, chlordane, chlorpyrifos). Although the estimated diameters are consistent with the measured diameters for the unattached fraction, the state of experimental and theoretical knowledge in this area is not sufficiently developed to judge the quantitative validity of these predictions. 48 refs., 1 fig., 5 tabs.

  3. Radon: Is it a problem

    SciTech Connect

    Hart, B.L.; Mettler, F.A.; Harley, N.H. )

    1989-09-01

    Radon gas is a major source of radiation exposure to the general public. Radon-222 is a product of uranium-238, present in varying concentrations in all soils. Radon enters buildings from soil, water, natural gas, and building materials. Its short-lived breakdown products, termed radon daughters, include alpha-emitting solids that can deposit in the lungs. Firm evidence links lung cancer risk in miners with high exposure to radon daughters. The amount of risk associated with the much lower but chronic doses received in buildings is difficult to establish. By some extrapolations, radon daughters may be responsible for a significant number of lung cancer deaths. The existence or extent of synergism with smoking is unresolved. Local conditions can cause high levels of radon in some buildings, and measures that reduce indoor radon are of potential value. 39 references.

  4. Radon Concentration in the Cataniapo-Autana River Basin, Amazonas State, Venezuela

    NASA Astrophysics Data System (ADS)

    Sajo-Bohus, L.; Greaves, E. D.; Alvarez, H.; Liendo, J.; Vásquez, G.

    2007-10-01

    Radon activity concentration is measured in rivers of the Autana-Cataniapo hydrologic basin. The region experiments mining and it is forecasted that the basin will be perturbed. Radon activity monitoring is one of the methods to measure environmental changes. Values of radon concentration in water range between 0.4 and 30 Bq L-1.

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

    PubMed

    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. Quantitative aspects of highly emanating geologic materials and their role in creating high indoor radon. Final report, April 1, 1994--March 31, 1996

    SciTech Connect

    Gundersen, L.C.S.; Schumann, R.R.; Gates, A.E.; Price, P.

    1996-12-31

    Indoor radon hot spots, areas where indoor radon commonly exceeds 20 pCi/L, are often caused by unusually highly emanating soils or rock and their interaction with ambient climatic conditions and a building`s architecture. Highly emanating soils and rocks include glacial deposits; dry fractured clays; black shales; limestone-derived soils; karst and cave areas, fractured or sheared granitic crystalline rocks; mine tailings; uraniferous backfill; and most uranium deposits. The above list probably accounts for 90% of the Nation`s indoor radon over 20 pCi/L. In several of these high indoor radon areas, there appears to be a link between the nature of the radon source in the ground, the architecture of the home, and the relative magnitude and ease of mitigation of the indoor air problem. Quantification of geologic materials in terms of their radon potential with respect to climatic and architectural considerations has never been accomplished. Recent studies have attempted semi-quantitative rankings but rigorous analysis has not been done. In this investigation the authors have attempted to develop the quantitative aspects of geologic materials for prediction of very high indoor radon at several scales of observation from national to census tract.

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

    PubMed

    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.

  8. Relationship among short- and long-term radon measurements within dwellings: Influence of radon concentrations

    SciTech Connect

    Klotz, J.B.; Schoenberg, J.B.; Wilcox, H.B. )

    1993-10-01

    As part of a retrospective epidemiologic study of lung cancer in women, alpha-track and charcoal canister radon measurements were made in a sample of New Jersey residences. The alpha-track measurements were designed to yield estimates of annual average exposures of dwelling occupants, while charcoal canister measurements were designed to yield worst case concentrations for screening purposes. The year-long living area and basement screening measurements had geometric means of 19 Bq m-3 (0.52 pCi L-1) and 56 Bq m-3 (1.5 pCi L-1), respectively. Measurements of radon gas with different detectors and on different floors were compared to each other within residences. Ratios of screening to annual average results became more extreme as the measured concentrations increased; the mean ratio of basement canisters to year-long living area alpha-track detectors was 5.6 vs. 2.7 for houses that screened above and below 150 Bq m-3 (4 pCi L-1), respectively. Although the residence sample from which these data were drawn is not necessarily representative of either state or national housing stock, these observations, if verified, may have important implications for procedures and decision strategies designed to reduce individual and population exposures to radon.

  9. The weather dependence of particle size distribution of indoor radioactive aerosol associated with radon decay products.

    PubMed

    Mostafa, A M A; Tamaki, K; Moriizumi, J; Yamazawa, H; Iida, T

    2011-07-01

    This study was performed to measure the activity size distribution of aerosol particles associated with short-lived radon decay products in indoor air at Nagoya University, Nagoya, Japan. The measurements were performed using a low pressure Andersen cascade impactor under variable meteorological conditions. The results showed that the greatest activity fraction was associated with aerosol particles in the accumulation size range (100-1000 nm) with a small fraction of nucleation mode (10-100 nm). Regarding the influence of the weather conditions, the decrease in the number of accumulation particles was observed clearly after rainfall without significant change in nucleation particles, which may be due to a washout process for the large particles.

  10. Radon

    MedlinePlus

    You can't see radon. And you can't smell it or taste it. But it may be a problem in your home. Radon comes from the natural breakdown of uranium in soil, rock, and water. Radon is the second leading cause of lung cancer ...

  11. Assessing the risks from exposure to radon in dwellings

    SciTech Connect

    Walsh, P.J.; Lowder, W.M.

    1983-07-01

    The factors used to assess the radiation dose and health risks from human exposure to radon in dwellings are critically reviewed in this summary. Sources of indoor radon and determinants of air concentrations and exposure levels are given as well as the uncertainties that exist in their formulation. Methods of assessing health effects from inhalation of radon and its progeny are discussed with emphasis on dosimetry of radon daughters and formulation of risk per dose values. Finally, methods of assessing risks for general population exposures to indoor radon concentrations are treated.

  12. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    NASA Astrophysics Data System (ADS)

    Kumar, Ajay; Sharma, Sumit

    2015-08-01

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  13. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    SciTech Connect

    Kumar, Ajay Sharma, Sumit

    2015-08-28

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  14. Indoor/outdoor concentrations of ozone and peroxyacetyl nitrate (PAN).

    PubMed

    Jakobi, G; Fabian, P

    1997-05-01

    Photochemical pollutants such as ozone and peroxyacetyl nitrate (PAN) could adversely affect human health, especially with relation to effects on lung function. For a realistic assessment of ambient concentrations, both outdoor and indoor measurements of ozone and PAN are required, because people stay indoors for most of the time. Indoor/outdoor concentration ratios, indoor half-life times and indoor chemistry including physicochemical reactions on surfaces are quite well known for ozone, but not for PAN. While ozone is removed very rapidly mainly by heterogeneous reactions on surfaces or by gasphase reactions with e.g. carpet emissions, no such processes are known for PAN at present. The main removal process for PAN is thermal decay. Indoor concentrations of ozone and PAN can be a significant fraction of those outdoors highly depending on the ventilation pattern. Our measurements in various kinds of non-air-conditioned rooms show maximal indoor concentrations between 80 and 100% of those outdoors for ozone and PAN, respectively. Average indoor/outdoor ratios were calculated of 0.5 for ozone and between 0.7 and 0.9 for PAN. The half-life times ranged between only a few minutes for ozone and 0.5 to 1 h for PAN.

  15. Distribution of Airborne Radon-222 Concentrations in U.S. Homes

    NASA Astrophysics Data System (ADS)

    Nero, A. V.; Schwehr, M. B.; Nazaroff, W. W.; Revzan, K. L.

    1986-11-01

    Apparently large exposures of the general public to the radioactive decay products of radon-222 present in indoor air have led to systematical appraisal of monitoring data from U.S. single-family homes; several ways of aggregating data were used that take into account differences in sample selection and season of measurements. The resulting distribution of annual-average radon-222 concentrations can be characterized by an arithmetic mean of 1.5 picocurie per liter (55 becquerels per cubic meter) and a long tail with 1 to 3% of homes exceeding 8 picocuries per liter, or by a geometric mean of 0.9 picocurie per liter and a geometric standard deviation of about 2.8. The standard deviation in the means is 15%, estimated from the number and variability of the available data sets, but the total uncertainty is larger because these data may not be representative. Available dose-response data suggest that an average of 1.5 picocuries per liter contributes about 0.3% lifetime risk of lung cancer and that, in the million homes with the highest concentrations, where annual exposures approximate or exceed those received by under-ground uranium miners, long-term occupants suffer an added lifetime risk of at least 2%, reaching extraordinary values at the highest concentrations observed.

  16. Radon exhalation from sub-slab aggregate used in home construction in Canada.

    PubMed

    Bergman, Lauren; Lee, Jaeyoung; Sadi, Baki; Chen, Jing

    2015-06-01

    Exposure to elevated levels of radon in homes has been shown to result in an increased risk of developing lung cancer. The two largest contributors to indoor radon are radon in soil gas, formed from the rocks and soil surrounding the home, and building materials such as aggregate. This study measured the surface radon exhalation rates for 35 aggregate samples collected from producers across Canada. The radon exhalation rates ranged from 2.3 to 479.9 Bq m(-2) d(-1), with a mean of 80.7±112 Bq m(-2) d(-1). Using a simple, conservative analysis, the aggregate contribution to radon concentrations in an unfinished basement was determined. The maximum estimated radon concentration was 32.5±2.7 Bq m(-3), or ~16 % of the Canadian Radon Guideline. It can be concluded that under normal conditions radon exhalation from aggregate contributes very little to the total radon concentration in indoor air.

  17. Radon: The Invisible Invader.

    ERIC Educational Resources Information Center

    School Leader, 1987

    1987-01-01

    A brief background on indoor radon and the health risks associated with radon exposure, with special emphasis on nonresidential buildings. One school district's experience in radon testing and monitoring is included. (MLF)

  18. Mapping indoor radon-222 in Denmark: design and test of the statistical model used in the second nationwide survey.

    PubMed

    Andersen, C E; Ulbak, K; Damkjaer, A; Kirkegaard, P; Gravesen, P

    2001-05-14

    In Denmark, a new survey of indoor radon-222 has been carried out, 1-year alpha track measurements (CR-39) have been made in 3019 single-family houses. There are from 3 to 23 house measurements in each of the 275 municipalities. Within each municipality, houses have been selected randomly. One important outcome of the survey is the prediction of the fraction of houses in each municipality with an annual average radon concentration above 200 Bq m(-3). To obtain the most accurate estimate and to assess the associated uncertainties, a statistical model has been developed. The purpose of this paper is to describe the design of this model, and to report results of model tests. The model is based on a transformation of the data to normality and on analytical (conditionally) unbiased estimators of the quantities of interest. Bayesian statistics are used to minimize the effect of small sample size. In each municipality, the correction is dependent on the fraction of area where sand and gravel is a dominating surface geology. The uncertainty analysis is done with a Monte-Carlo technique. It is demonstrated that the weighted sum of all municipality model estimates of fractions above 200 Bq m(-3) (3.9% with 95%-confidence interval = [3.4,4.5]) is consistent with the weighted sum of the observations for Denmark taken as a whole (4.6% with 95%-confidence interval = [3.8,5.6]). The total number of single-family houses within each municipality is used as weight. Model estimates are also found to be consistent with observations at the level of individual counties. These typically include a few hundred house measurements. These tests indicate that the model is well suited for its purpose.

  19. Radon exchange dynamics in a karst system investigated by radon continuous measurements in water: first results.

    PubMed

    Peano, G; Vigna, B; Villavecchia, E; Agnesod, G

    2011-05-01

    In 2008 the underground Karst Laboratory of Bossea Cave started research on radon exchange dynamics between bedrock, cave waters (main collector and percolations) and indoor underground atmosphere. Radon air concentrations, normally high, increase more and more during the collector's floods. An explanation of this is a radon-water solubilisation process more effective in flood events, because of a greater rock-water contact surface. Radon is then carried by water into the cave and released into the air. To verify this, continuous measurements of radon concentration are needed not only in the air, but also in the waters of the cave. So a new device for continuous radon monitoring in water was tested, connected to the AlphaGuard radon monitor. For the first 6 months of 2010, for different sections of the cave, the correlations between radon in the air, radon in the waters and the collector's stream flow fluctuations were presented and discussed. PMID:21586541

  20. A comparison of radon and its decay products' behaviour in indoor air.

    PubMed

    Trevisi, R; Cardellini, F; Leonardi, F; Vargas Trassierra, C; Franci, D

    2014-11-01

    The inhalation of short-lived radon decay products (RDP) yields the greatest contribution to the natural radiation exposure. This paper deals with a study carried out to improve the knowledge of the behaviour of RDPs, their interaction with particulates and the plateout during the time. The tests confirmed that a high aerosol particle concentration increases the probability that an ion sticks to aerosol and remains long in the air, leading to both an increase of F and a decrease of fp, as reported in the literature. The same experimental protocol applied in a small radon chamber showed a strong reduction of the equilibrium factor (an average of ∼10 %), because in a small environment the plateout phenomenon prevails on the attachment to particulate.

  1. Reconnaissance techniques for determining soil-gas radon concentrations: an example from Prince Georges County, Maryland

    USGS Publications Warehouse

    Reimer, G.M.

    1990-01-01

    Radon reconnaissance requires some special considerations because a large area must be covered in a short period of time and analyses must be made soon after collection because of Rn decay. A simple approach to collection and field analysis consists of a small-diameter probe pounded into the ground to a depth of at least 0.75 m. Analysis is by an alpha-scintillometer. Soil-gas samples collected along a traverse in Prince Georges County, Maryland, demonstrates the utility of the technique. The reconnaissance sampling revealed Rn soil-gas concentrations of up to 2500 pCi/L (picocuries per liter) indicating that the potential exists for indoor accumulations in excess of 4 pCi/L. -from Author

  2. An empirical model to predict indoor NO 2 concentrations

    NASA Astrophysics Data System (ADS)

    Kulkarni, Milind M.; Patil, Rashmi S.

    This paper discusses the development of an empirical model to predict indoor NO 2 concentration ( Cin) from outdoor NO 2 concentration ( Cout) measured just outside the homes. Concentrations were 48-h time integrated averages. Data from a study carried out on measurement of indoor, outdoor and personal exposure to nitrogen dioxide (NO 2) in Mumbai were used in the development of the model. Concentrations were measured over 2-day periods both in winter (February 1996) and summer (April 1996) for 43 respondents. The form of the developed model is C¯in=k C¯out+S/Q, where k, the ventilation factor and S/ Q the source term are the model constants. Analysis of variance and regression analysis indicated that type of fuel was the most significant factor influencing indoor concentration and model constants. Measured indoor concentrations were regressed on outdoor concentrations to evaluate model constants for kerosene and liquefied petroleum gas (LPG), which are the most predominantly used cooking fuels in Indian households. Final models, after evaluating the constants suggested that contribution to indoor NO 2 concentration due to indoor sources was higher in kerosene using households whereas in the case of LPG using households, the contribution due to outdoor sources was relatively higher. Results of model validation indicated that the predictive power of the models was good.

  3. Variation of radon entry rate into two detached houses

    NASA Astrophysics Data System (ADS)

    Keskikuru, T.; Kokotti, H.; Lammi, S.; Kalliokoski, P.

    The influence of various factors on the concentration of indoor and its variation were investigated statistically in two different types and location of houses. In the single-storey slab-on-grade house (A), the variation of indoor radon closely followed the difference in indoor-outdoor temperature. The measured pressure difference across the wall and wind speed were significant variables ( p<0.00), but these factors explained the variation of the radon concentration only slightly. In the two-storey hillside basement house (B), the most significant variable difference in indoor-attic space explained 28% of the variation of the indoor radon. In both houses, the coefficient of determination increased slightly when the average wind speed increased, but in house B the coefficient decreased with high wind speed. In house A, the highest concentration of indoor radon was observed as the wind-induced internal transport of radon. In house B, the highest concentration of indoor radon occurred and the highest coefficient of determination (100 R2%=89%) was observed when the wind was blowing towards the slope-side of the esker, causing increased soil gas pressure and air flow in soil. According to this study, the effect of the wind speed on the concentration of indoor radon and on the coefficient of determination was difficult to foresee because the effect of the wind on soil depended strongly on the wind direction and location of the houses.

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

    SciTech Connect

    Cauwels, P.; Poffijn, A.

    2000-05-01

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

  5. AN INDOOR PESTICIDE AIR AND SURFACE CONCENTRATION MODEL

    EPA Science Inventory

    A thorough assessment of human exposure to environmental chemicals requires consideration of all processes in the sequence from source to dose. For assessment of exposure to pesticides following their use indoors, data and models are needed to estimate pesticide concentrations...

  6. Estimation of radon concentrations in coal mines using a hybrid technique calibration curve.

    PubMed

    Jamil, K; Ali, S

    2001-01-01

    The results of epidemiological studies in various countries show that radon and its progeny cause carcinogenic effects on mine workers. Therefore, it becomes of paramount importance to monitor radon concentrations and consequently determine the radon dose rates in coal mines for the protection of coal miners. A new calibration curve was obtained for radon concentration estimation using hybrid techniques. A calibration curve was generated using 226Ra activity concentration measured by a HPGe detector-based gamma-ray spectrometer versus alpha-track-density rate due to radon and its progeny on CR-39 track detector. Using the slope of the experimentally determined curve in the units of Becqueral per kilogram (Bq kg-1) per unit alpha-track-density per hour (cm-2 h-1), radon concentrations (Bq m-3) were estimated using coal samples from various coal mines in two provinces of Pakistan, Punjab and Balochistan. Consequently, radon dose rates were computed in the simulated environment of the coal mines. Results of these computations may be considered with a caveat that the method developed in this paper provides only a screening method to indicate the radon dose in coal mines. It has been shown that the actual measurements of radon concentrations in the coal mines are in agreement with the estimated radon concentrations using the hybrid-technique calibration curve.

  7. Radon Monitoring Results BPA Residential Weatherization Program, Report Number 1.

    SciTech Connect

    United States. Bonneville Power Administration.

    1986-01-01

    In October 1984, the Bonneville Power Administration (BPA) began offering free radon monitoring to participants of its regionwide Residential Weatherization Program. The purpose of the radon monitoring is to provide information to participating homeowners or consumers on the average radon concentrations within their residences. This radon concentration information and other information on indoor air quality (IAQ) is provided to assist homeowners on their decision to install ''house-tightening'' weatherization measures. This radon report will present background information on why BPA decided to offer radon monitoring, the procedures used for monitoring, the extent of BPA radon monitoring in the region, and results of this monitoring. Subsequent BPA radon monitoring reports will be produced on a quarterly basis which will include a brief narrative on the radon monitoring and provide a summary of the radon data received to date.

  8. Contribution of waterborne radon to home air quality

    SciTech Connect

    Deb, A.K.

    1994-12-31

    Radon-222 is a member of the uranium decay chain and is formed from the decay of radium-226. Radon and its decay products emit alpha particles during the decay process. If radon is inhaled, alpha particles emitted from inhaled radon and its daughters increase the risk of lung cancer. Radon is soluble in water; thus when radon comes in contact with groundwater it dissolves. The radon concentration in groundwater may range from 100 pCi/L to 1,000,000 pCi/L. When water with a high radon level is used in the home, radon is released from the water to the air and thus can increase indoor air radon concentration. Considering the estimated health risk from radon in public water supply systems, EPA has proposed a maximum contaminant level (MCL) of 300 pCi/L for radon in public drinking water supplies. To address the health risks of radon in water and the proposed regulations, the American Water Works Association Research Foundation (AWWARF) initiated a study to determine the contribution of waterborne radon to radon levels in indoor household air.

  9. Automobile proximity and indoor residential concentrations of BTEX and MTBE

    SciTech Connect

    Corsi, Dr. Richard; Morandi, Dr. Maria; Siegel, Dr. Jeffrey; Hun, Diana E

    2011-01-01

    Attached garages have been identified as important sources of indoor residential air pollution. However, the literature lacks information on how the proximity of cars to the living area affects indoor concentrations of gasoline-related compounds, and the origin of these pollutants. We analyzed data from the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study and evaluated 114 residences with cars in an attached garage, detached garage or carport, or without cars. Results indicate that homes with cars in attached garages were affected the most. Concentrations in homes with cars in detached garages and residences without cars were similar. The contribution from gasoline-related sources to indoor benzene and MTBE concentrations appeared to be dominated by car exhaust, or a combination of tailpipe and gasoline vapor emissions. Residing in a home with an attached garage could lead to benzene exposures ten times higher than exposures from commuting in heavy traffic.

  10. Radon-Induced Health Effects

    NASA Astrophysics Data System (ADS)

    Muirhead, C. R.

    The following sections are included: * Lung Cancer * Studies of miners * Estimates of lifetime risk associated with indoor radon exposure * Factors that may affect risk estimates * Sex and age at exposure * Joint effect of radon and smoking * Exposure rate * Epidemiological studies of lung cancer and indoor radon exposure * Cancers Other Than Lung * Dosimetry * Epidemiological studies * Studies of miners * Indoor radon exposure * Concluding Remarks * References

  11. Radioactivity in the indoor building environment in Serbia.

    PubMed

    Todorović, Natasa; Bikit, Istvan; Vesković, Miroslav; Krmar, Miodrag; Mrđa, Dusan; Forkapić, Sofija; Hansman, Jan; Nikolov, Jovana; Bikit, Kristina

    2014-01-01

    Measurement of activity concentrations of radionuclides in building materials and radon in indoor space is important in the assessment of population exposures, as most individuals spend 80 % of their time indoors. This paper presents the results of activity concentration measurements of: radon emanated from the soil, radionuclides (226)Ra, (232)Th and (40)K in the soil, indoor radon in the city of Novi Sad (the capital city of Vojvodina) using charcoal canisters and indoor radon in the Vojvodina region using alpha-track detectors and the radioactivity of some building materials. Influences of floor level, space under the rooms, boarding, and the heating system on indoor radon accumulation in the Vojvodina province, situated in the northern part of Serbia, are also presented in this paper. The total effective dose and the activity concentration index are calculated applying the dose criteria recommended by the European Union for building materials.

  12. Dosimetry modelling of transient radon and progeny concentration peaks: results from in situ measurements in Ikaria spas, Greece.

    PubMed

    Nikolopoulos, Dimitrios; Vogiannis, Efstratios; Petraki, Ermioni; Kottou, Sofia; Yannakopoulos, Panayiotis; Leontaridou, Maria; Louizi, Anna

    2013-06-01

    Radon and progeny ((218)Po, (214)Pb, (214)Bi and (214)Po) are radioactive indoor pollutants recognised for the human radiation burden that they induce. Bathing in thermal spas causes transient concentration peaks of radon and progeny and additional short-term impact in patients and personnel. This paper reports a semi-empirical non-linear first order model for describing radon and progeny variations in treatment rooms of the Ikaria spas. Non-measured physical parameters were estimated from in situ measurements in Ikaria through non-linear numerical solving. Exposure and dose variations were additionally modelled. Attachment rate constants were found to be between 0.44 and 55 h(-1). Deposition rate constants were between 0.28 and 7.3 h(-1) for attached nuclei and 0.42 and 64 h(-1) for unattached nuclei. Unattached progeny peaks were right-shifted compared to those of radon. Modelled effective doses ranged between 0.001 mSv per year and 0.589 mSv per year for patients and between 0.001 mSv per year and 18.9 mSv per year for workers. Apollon spas presented quite high doses. These were the highest reported in Greece and are significant worldwide.

  13. Measurements of radon concentrations in waters and soil gas of Zonguldak, Turkey.

    PubMed

    Koray, Abdullah; Akkaya, Gizem; Kahraman, Ayşegül; Kaynak, Gökay

    2014-12-01

    The radon concentrations in soil-gas and water samples (in the form of springs, catchment, tap, thermal) used as drinking water or thermal were measured using a professional radon monitor AlphaGUARD PQ 2000PRO. The measured radon concentrations in water samples ranged from 0.32 to 88.22 Bq l(-1). Most of radon levels in potable water samples are below the maximum contaminant level of 11 Bq l(-1) recommended by the US Environmental Protection Agency. The calculated annual effective doses due to radon intake through water consumption varied from 0.07 to 18.53 µSv y(-1). The radon concentrations in soil gas varied from 295.67 to 70 852.92 Bq m(-3). The radon level in soil gas was found to be higher in the area close to the formation boundary thrust and faults. No correlation was observed between radon concentrations in groundwater and soil gas. Also, no significant correlation was observed between soil-gas radon and temperature, pressure and humidity. The emanation of radon from groundwater and soil gas is controlled by the geological formation and by the tectonic structure of the area. PMID:24287600

  14. Indoor radon pollution: Control and mitigation. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-05-01

    The bibliography contains citations concerning the control and mitigation of radon pollution in homes and commercial buildings. Citations cover radon transport studies in buildings and soils, remedial action proposals on contaminated buildings, soil venting, building ventilation, sealants, filtration systems, water degassing, reduction of radon sources in building materials, and evaluation of existing radon mitigation programs, including their cost effectiveness. Analysis and detection of radon and radon toxicity are covered in separate published bibliographies. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  15. Indoor radon pollution: Control and mitigation. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    Not Available

    1994-04-01

    The bibliography contains citations concerning the control and mitigation of radon pollution in homes and commercial buildings. Citations cover radon transport studies in buildings and soils, remedial action proposals on contaminated buildings, soil venting, building ventilation, sealants, filtration systems, water degassing, reduction of radon sources in building materials, and evaluation of existing radon mitigation programs, including their cost effectiveness. Analysis and detection of radon and radon toxicity are covered in separate published bibliographies. (Contains 250 citations and includes a subject term index and title list.)

  16. Measurements of radon gas concentrations in dwellings of Al-Madinah Al-Munawarah province in Saudi Arabia.

    PubMed

    Mohamed, R I; Alfull, Z Z; Dawood, N D

    2014-01-01

    Indoor radon concentration levels in a large number of dwellings in Al-Madinah Al-Munawarah Province have been measured. Al-Madinah Al-Munawarah is in the western region of Saudi Arabia. It is the second holiest city in Islam after Mecca, because it is the burial place of the Islamic Prophet Muhammad. The city was divided into four regions: western (contains nine sites), eastern (contains six sites), northern (contains nine sites) and southern (contains five sites). Radon gas concentration was measured using the closed chamber technique employing 2×2 cm(2) sheets of CR-39 solid-state nuclear track detectors. The detectors were kept for a period of 5 to 6 months from September 2010 to February 2011 in order to expose to radon gas. The results of the survey in the western and eastern sites showed that the overall minimum, maximum and average radon concentration levels were 20±1.6, 27±3.2 and 21±2.5 Bq m(-3), respectively. The lowest average radon concentration (20±1.6 Bq m(-3)) was found in Al Anabes and Al Suqya in the western region and Bani Dhafar in the eastern region, while the highest average concentration (27±3.2 Bq m(-3)) was found in Teeyba in the western region and Al 'Aridh in the eastern region, with an average of 21±2.5 Bq m(-3) in the western and eastern sites of Al-Madinah Al-Munawarah. Also in the northern region, the minimum radon concentration was 20±1.6 Bq m(-3) in Oyun, while the maximum was 42±1.6 Bq m(-3) in Sayyed al Shuhadd and Hai Nasr. In the southern region, the minimum radon concentration was 25±2.6 Bq m(-3) at Hai Al Hejrah, while the maximum value was 37±2.6 Bq m(-3) at Al Awali and Dawadia. The average radon concentration was 26±2.5 Bq m(-3) for Al-Madinah Al-Munawarah (western, eastern, northern and southern regions). The corresponding annual effective dose E (mSv y(-1)) to public from (222)Rn and its progeny was estimated to be 0.66 mSv y(-1) as an average value for Al-Madinah Al-Munawarah. The authors concluded that all

  17. Dose assessment to inhalation exposure of indoor 222Rn daughters in Korea.

    PubMed

    Ha, C W; Chang, S Y; Lee, B H

    1992-10-01

    Long-term, average indoor 222Rn concentrations were measured in 12 residential areas by passive CR-39 radon cups. Corresponding equilibrium-equivalent concentration of radon daughters were derived. The resulting effective dose equivalent for the Korean population due to inhalation exposure of this equilibrium-equivalent concentration of radon daughters was then evaluated.

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

    PubMed Central

    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

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

    PubMed

    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.

  20. Contribution of radon and radon daughters to respiratory cancer

    SciTech Connect

    Harley, N.; Samet, J.M.; Cross, F.T.; Hess, T.; Muller, J.; Thomas, D.

    1986-12-01

    This article reviews studies on the contribution of radon and radon daughters to respiratory cancer and proposes recommendations for further research, particularly a national radon survey. The steady-state outdoor radon concentration averages 200 pCi/m3, and indoor levels are about 4 times higher. The primary source of radon in homes is the underlying soil; entry depends on multiple variables and reduced ventilation for energy conservation increases indoor radon levels. Occupational exposures are expressed in units of radon daughter potential energy concentration or working level (WL). Cumulative exposure is the product of the working level and the time exposed. The unit for cumulative exposure is the working level month (WLM). The occupational standard for radon exposure is 4 WLM/year, and 2 WLM/year has been suggested as a guideline for remedial action in homes. Epidemiologic studies show that miners with cumulative radon daughter exposures somewhat below 100 WLM have excess lung cancer mortality. Some 3% to 8% of miners studied have developed lung cancer attributable to radon daughters. All of the underground mining studies show an increased risk of lung cancer with radon daughter exposure. All cell types of lung cancer increased with radon exposure. If radon and smoking act in a multiplicative manner, then the risk for smokers could be 10 times that for nonsmokers. The potential risk of lung cancer appears to be between 1 and 2 per 10,000/WLM, which yields a significant number of lung cancers as some 220 million persons in the United States are exposed on average to 10 to 20 WLM/lifetime.

  1. Contribution of radon and radon daughters to respiratory cancer.

    PubMed Central

    Harley, N; Samet, J M; Cross, F T; Hess, T; Muller, J; Thomas, D

    1986-01-01

    This article reviews studies on the contribution of radon and radon daughters to respiratory cancer and proposes recommendations for further research, particularly a national radon survey. The steady-state outdoor radon concentration averages 200 pCi/m3, and indoor levels are about 4 times higher. The primary source of radon in homes is the underlying soil; entry depends on multiple variables and reduced ventilation for energy conservation increases indoor radon levels. Occupational exposures are expressed in units of radon daughter potential energy concentration or working level (WL). Cumulative exposure is the product of the working level and the time exposed. The unit for cumulative exposure is the working level month (WLM). The occupational standard for radon exposure is 4 WLM/year, and 2 WLM/year has been suggested as a guideline for remedial action in homes. Epidemiologic studies show that miners with cumulative radon daughter exposures somewhat below 100 WLM have excess lung cancer mortality. Some 3% to 8% of miners studied have developed lung cancer attributable to radon daughters. All of the underground mining studies show an increased risk of lung cancer with radon daughter exposure. All cell types of lung cancer increased with radon exposure. If radon and smoking act in a multiplicative manner, then the risk for smokers could be 10 times that for nonsmokers. The potential risk of lung cancer appears to be between 1 and 2 per 10,000/WLM, which yields a significant number of lung cancers as some 220 million persons in the United States are exposed on average to 10 to 20 WLM/lifetime. PMID:3830103

  2. CONTRIBUTIONS OF BUILDING MATERIALS TO INDOOR RADON LEVELS IN FLORIDA BUILDINGS

    EPA Science Inventory

    The report documents work to characterize potential radon sources in concretes and recommend related changes to Florida's building materials radium standard. (NOTE: The Florida Standard for Radon-resistant Residential Building Construction originally contained a provision to limi...

  3. Canadian population risk of radon induced lung cancer: a re-assessment based on the recent cross-Canada radon survey

    PubMed Central

    Chen, J.; Moir, D.; Whyte, J.

    2012-01-01

    Exposure to indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. Canadian population risk of radon induced lung cancer was assessed in 2005 with the radon distribution characteristics determined from a radon survey carried out in the late 1970s in 19 cities. In that survey, a grab sampling method was used to measure radon levels. The observed radon concentration in 14 000 Canadian homes surveyed followed a log–normal distribution with a geometric mean (GM) of 11.2 Bq m–3 and a geometric standard deviation (GSD) of 3.9. Based on the information from that survey, it was estimated that ∼10 % of lung cancers in Canada resulted from indoor radon exposure. To gain a better understanding of radon concentrations in homes across the country, a national residential radon survey was launched in April 2009. In the recent survey, long-term (3 month or longer) indoor radon measurements were made in roughly 14 000 homes in 121 health regions across Canada. The observed radon concentrations follow, as expected, a log–normal distribution with a GM of 41.9 Bq m–3 and a GSD of 2.8. Based on the more accurate radon distribution characteristics obtained from the recent cross-Canada radon survey, a re-assessment of Canadian population risk for radon induced lung cancer was undertaken. The theoretical estimates show that 16 % of lung cancer deaths among Canadians are attributable to indoor radon exposure. These results strongly suggest the ongoing need for the Canadian National Radon Program. In particular, there is a need for a focus on education and awareness by all levels of government, and in partnership with key stakeholders, to encourage Canadians to take action to reduce the risk from indoor radon exposure. PMID:22874897

  4. Canadian population risk of radon induced lung cancer: a re-assessment based on the recent cross-Canada radon survey.

    PubMed

    Chen, J; Moir, D; Whyte, J

    2012-11-01

    Exposure to indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. Canadian population risk of radon induced lung cancer was assessed in 2005 with the radon distribution characteristics determined from a radon survey carried out in the late 1970s in 19 cities. In that survey, a grab sampling method was used to measure radon levels. The observed radon concentration in 14,000 Canadian homes surveyed followed a log-normal distribution with a geometric mean (GM) of 11.2 Bq m(-3) and a geometric standard deviation (GSD) of 3.9. Based on the information from that survey, it was estimated that ∼10 % of lung cancers in Canada resulted from indoor radon exposure. To gain a better understanding of radon concentrations in homes across the country, a national residential radon survey was launched in April 2009. In the recent survey, long-term (3 month or longer) indoor radon measurements were made in roughly 14 000 homes in 121 health regions across Canada. The observed radon concentrations follow, as expected, a log-normal distribution with a GM of 41.9 Bq m(-3) and a GSD of 2.8. Based on the more accurate radon distribution characteristics obtained from the recent cross-Canada radon survey, a re-assessment of Canadian population risk for radon induced lung cancer was undertaken. The theoretical estimates show that 16 % of lung cancer deaths among Canadians are attributable to indoor radon exposure. These results strongly suggest the ongoing need for the Canadian National Radon Program. In particular, there is a need for a focus on education and awareness by all levels of government, and in partnership with key stakeholders, to encourage Canadians to take action to reduce the risk from indoor radon exposure.

  5. Assessing exposure to granite countertops--Part 2: Radon.

    PubMed

    Allen, Joseph G; Minegishi, Taeko; Myatt, Theodore A; Stewart, James H; McCarthy, John F; Macintosh, David L

    2010-05-01

    Radon gas ((222)Rn) is a natural constituent of the environment and a risk factor for lung cancer that we are exposed to as a result of radioactive decay of radium ((226)Ra) in stone and soil. Granite countertops, in particular, have received recent media attention regarding their potential to emit radon. Radon flux was measured on 39 full slabs of granite from 27 different varieties to evaluate the potential for exposure and examine determinants of radon flux. Flux was measured at up to six pre-selected locations on each slab and also at areas identified as potentially enriched after a full-slab scan using a Geiger-Muller detector. Predicted indoor radon concentrations were estimated from the measured radon flux using the CONTAM indoor air quality model. Whole-slab average emissions ranged from less than limit of detection to 79.4 Bq/m(2)/h (median 3.9 Bq/m(2)/h), similar to the range reported in the literature for convenience samples of small granite pieces. Modeled indoor radon concentrations were less than the average outdoor radon concentration (14.8 Bq/m(3); 0.4 pCi/l) and average indoor radon concentrations (48 Bq/m(3); 1.3 pCi/l) found in the United States. Significant within-slab variability was observed for stones on the higher end of whole slab radon emissions, underscoring the limitations of drawing conclusions from discrete samples.

  6. Radon monitoring and hazard prediction in Ireland

    NASA Astrophysics Data System (ADS)

    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

  7. Indoor Air VOC Concentrations in Suburban and Rural New Jersey

    PubMed Central

    WEISEL, CLIFFORD P.; ALIMOKHTARI, SHAHNAZ; SANDERS, PAUL F.

    2014-01-01

    Indoor VOC air concentrations of many compounds are higher than outdoor concentrations due to indoor sources. However, most studies have measured residential indoor air in urban centers so the typical indoor air levels in suburban and rural regions have not been well characterized. Indoor VOC air concentrations were measured in 100 homes in suburban and rural areas in NJ to provide background levels for investigations of the impact from subsurface contamination sources. Of the 57 target compounds, 23 were not detected in any of the homes, and 14 compounds were detected in at least 50% of the homes with detection limits of ~1 μg/m3. The common compounds identified included aromatic and aliphatic hydrocarbons from mobile sources, halogenated hydrocarbons commonly used in consumer products or from chlorinated drinking water, acetone and 2-butanone emitted from cosmetic products, and Freons. Typical concentrations were in the low μg/m3 range, though values of tens, hundreds or even thousands of μg/m3 were measured in individual homes in which activities related to specific sources of VOCs were reported. Compounds with known similar sources were highly correlated. The levels observed are consistent with concentrations found in the air of urban homes. PMID:19068799

  8. Indoor air VOC concentrations in suburban and rural New Jersey.

    PubMed

    Weisel, Clifford P; Alimokhtari, Shahnaz; Sanders, Paul F

    2008-11-15

    Indoor VOC air concentrations of many compounds are higher than outdoor concentrations due to indoor sources. However, most studies have measured residential indoor air in urban centers so the typical indoor air levels in suburban and rural regions have not been well characterized. Indoor VOC air concentrations were measured in 100 homes in suburban and rural areas in NJ to provide background levels for investigations of the impact from subsurface contamination sources. Of the 57 target compounds, 23 were not detected in any of the homes, and 14 compounds were detected in at least 50% of the homes with detection limits of approximately 1 microg/m3. The common compounds identified included aromatic and aliphatic hydrocarbons from mobile sources, halogenated hydrocarbons commonly used in consumer products or from chlorinated drinking water, acetone and 2-butanone emitted from cosmetic products, and Freons. Typical concentrations were in the low microg/m3 range, though values of tens, hundreds or even thousands of microg/m3 were measured in individual homes in which activities related to specific sources of VOCs were reported. Compounds with known similar sources were highly correlated. The levels observed are consistent with concentrations found in the air of urban homes. PMID:19068799

  9. Study of radon concentrations in oil refinery premises and city dwellings.

    PubMed

    Singh, A K; Khan, A J; Prasad, R

    2001-06-01

    Radon and its progeny concentrations were measured in several dwellings at an oil refinery premises and these concentrations were compared with those found in dwellings in Mathura and Agra cities. Radon progeny concentrations were measured using LR-115 type II nuclear track etch detectors. The radon concentrations were estimated by using a value of 0.42 for the equilibrium factor. The geometric means (GM) of radon concentrations in the refinery dwellings, Mathura city and Agra city dwellings were 97, 91 and 75 Bq m(-3) with geometric standard deviations of 1.7, 1.8 and 1.8 respectively. The average lifetime risk of lung cancer for an adjusted annual average chronic radon exposure of 69 Bq m(-3) (7.8 mWL; WL = working level) with an occupancy factor of 0.7 comes out to be 5.4 x 10(-3).

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

    PubMed

    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.

  11. Impact of lignite and hydrocarbon accumulations on {sup 222}Radon concentrations in drinking water supplies

    SciTech Connect

    Wolosz, T.H.

    1995-09-01

    Lignite and hydrocarbon accumulations are efficient uranium sinks, and {sup 222}Radon has been associated with the presence of hydrocarbon-trapping faults and salt domes. Lung exposure to this radioactive respiratory carcinogen can result upon the release of radon from domestic water during normal household activities. To determine if an association was present between elevated radon levels and factors affecting the distribution of {sup 238}Uranium and its decay products, 27 individual water wells and 48 public water systems of nine rural counties in and adjacent to an Texas Eocene Wilcox lignite belt were sampled and the water assayed. Radon levels in these water supplies ranged from <10 to 1359 pCi 1{sup -1}. Statistical analysis of radon concentrations and variables representing the presence of potential sinks was performed. A highly significant model (P,0.001) that explained 21.3% of radon variation. Mapping showed the highest radon concentrations were from lignite belt samples, which suggests that lignite may be a radionuclide source. The proposed standard for radon in public drinking water supplies is 300 pCi1{sup -1}. Thus, the demonstrated association between elevated radon concentrations and petroleum fields and low-rank coal may provide an informational tool for decision-making with regard to drilling public and private domestic water wells in the Eastern United States.

  12. Radon remediation of a two-storey UK dwelling by active sub-slab depressurisation: effects and health implications of radon concentration distributions.

    PubMed

    Allison, C C; Denman, A R; Groves-Kirkby, C J; Phillips, P S; Tornberg, R

    2008-10-01

    Radon concentration levels in a two-storey detached single-family dwelling in Northamptonshire, UK, were monitored continuously throughout a 5-week period during which active sub-slab depressurisation remediation measures were installed. Remediation of the property was accomplished successfully, with both the mean radon levels and the diurnal variability greatly reduced both upstairs and downstairs. Following remediation, upstairs and downstairs radon concentrations were 33% and 18% of their pre-remediation values respectively: the mean downstairs radon concentration was lower than that upstairs, with pre- and post-remediation values of the upstairs/downstairs concentration ratio, R(U/D), of 0.81 and 1.51 respectively. Cross-correlation between upstairs and downstairs radon concentration time-series indicates a time-lag of the order of 1 h or less, suggesting that diffusion of soil-derived radon from downstairs to upstairs either occurs within that time frame or forms a relatively insignificant contribution to the upstairs radon level. Cross-correlation between radon concentration time-series and the corresponding time-series for local atmospheric parameters demonstrated correlation between radon concentrations and internal/external pressure difference prior to remediation; this correlation disappears following remediation. Overall, these observations provide further evidence that radon concentration levels within a dwelling are not necessarily wholly determined by the effects of soil-gas advection, and further support the suggestion that, depending on the precise content of the building materials, upstairs radon levels, in particular, may be dominated by radon exhalation from the walls of the dwelling, especially in areas of low soil-gas radon.

  13. International comparison of cave radon concentrations identifying the potential alpha radiation risks to British cave users

    SciTech Connect

    Hyland, R.; Gunn, J.

    1994-08-01

    Elevated concentrations of {sup 222}Rn have been recorded in many limestone caves throughout the world. As prolonged exposure to high radon concentrations has been linked to cancer and tumors, particularly of the lung, a national survey of radon in British caves was undertaken. Passive radon detectors were exposed at 250 sites in 47 caves over four 7-d sampling periods. Mean concentrations ranging from 454-8,868 Bq m{sup {minus}3} were recorded. In one system, in the Peak District, radon concentrations of 155,000 Bq m{sup {minus}3} were recorded. The results indicate that the potential radiation dose from a single 4-h trip could exceed the national average annual background radiation dose (for the UK) from radon of 1.25 mSv. 18 refs., 3 tabs.

  14. Reduction of radon daughter concentrations in structures. [UMTRA project

    SciTech Connect

    Not Available

    1982-12-01

    A structure was identified in Salt Lake City wherein uranium mill tailings had been used in the construction and where unusually high levels of radon daughter concentrations (RDC's) existed. The physical and radiological characteristics of the structure were assessed. Ventilation techniques were investigated to assess their effectiveness in reducing RDC's. A preferred set of equipment was identified, installed in the structure and operated to reduce RDC's. Parametric studies were conducted to determine if supplying fresh air or recirculating air through electrostatic precipitators is more effective in reducing RDC's. Fresh air was found to be more effective in reducing RDC's. RDC's have been reduced to levels at or near the target of 0.03 working level under optimal ventilation conditions. Natural gas consumption with the new equipment is about 39% higher than with the original equipment. Electrical energy usage and electrical demand are respectively 50 and 44% higher with the new equipment than with the original equipment. 16 refs., 14 figs., 8 tabs.

  15. Radon and radon daughter measurements in solar buildings.

    PubMed

    George, A C; Knutson, E O; Franklin, H

    1983-08-01

    Measurements of radon and radon daughters in 11 buildings in five states, using active or passive solar heating, showed no significant excess in concentrations over the levels measured in buildings with conventional heating systems. Radon levels in two buildings using rock storage in their active solar systems exceeded the U.S. Nuclear Regulatory Commission's limit of 3 pCi/l. for continuous exposure in uncontrolled areas. In the remainder of the buildings, radon concentrations were found to be at levels considered to be normal. It appears that the slightly elevated indoor radon concentrations result from the local geological formations and from the tightening of the buildings rather than as a result of the solar heating technology. PMID:6885442

  16. Preliminary investigation of radon concentration in surface water and drinking water in Shenzhen City, South China.

    PubMed

    Li, Ting; Wang, Nanping; Li, Shijun

    2015-11-01

    A radon survey in surface water and drinking water was conducted using a portable degassing system associated with an ionisation chamber AlphaGUARD (PQ2000) for understanding levels of dissolved radon ((222)Rn) concentration in different types of water sources and risk assessment of radon in drinking water in Shenzhen City (SC) with a population of 10 628 900 in 2013, Guangdong Province of China. The measurements show that arithmetic means ± standard deviations of radon ((222)Rn) concentration are 52.05 ± 6.64, 0.29 ± 0.26, 0.15 ± 0.23 and 0.37 ± 0.42 kBq m(-3) in spring water, surface water, large and small public water supplies, respectively. Only radon concentrations of two water samples collected in mountainous areas are more than 11.10 kBq m(-3), exceeding the limit of radon concentration in drinking water stipulated by the national standard of China (GB5749-2006). The annual effective doses due to radon in drinking water were also calculated. The investigation suggests that there are no risks caused by radon in the drinking water in SC.

  17. Preliminary investigation of radon concentration in surface water and drinking water in Shenzhen City, South China.

    PubMed

    Li, Ting; Wang, Nanping; Li, Shijun

    2015-11-01

    A radon survey in surface water and drinking water was conducted using a portable degassing system associated with an ionisation chamber AlphaGUARD (PQ2000) for understanding levels of dissolved radon ((222)Rn) concentration in different types of water sources and risk assessment of radon in drinking water in Shenzhen City (SC) with a population of 10 628 900 in 2013, Guangdong Province of China. The measurements show that arithmetic means ± standard deviations of radon ((222)Rn) concentration are 52.05 ± 6.64, 0.29 ± 0.26, 0.15 ± 0.23 and 0.37 ± 0.42 kBq m(-3) in spring water, surface water, large and small public water supplies, respectively. Only radon concentrations of two water samples collected in mountainous areas are more than 11.10 kBq m(-3), exceeding the limit of radon concentration in drinking water stipulated by the national standard of China (GB5749-2006). The annual effective doses due to radon in drinking water were also calculated. The investigation suggests that there are no risks caused by radon in the drinking water in SC. PMID:25904699

  18. Results of simultaneous radon and thoron measurements in 33 metropolitan areas of Canada.

    PubMed

    Chen, Jing; Bergman, Lauren; Falcomer, Renato; Whyte, Jeff

    2015-02-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. (222)Rn (radon gas) and (220)Rn (thoron gas) are the most common isotopes of radon. In order to assess thoron contribution to indoor radon and thoron exposure, a survey of residential radon and thoron concentrations was initiated in 2012 with ∼4000 homes in the 33 census metropolitan areas of Canada. The survey confirmed that indoor radon and thoron concentrations are not correlated and that thoron concentrations cannot be predicted from widely available radon information. The results showed that thoron contribution to the radiation dose varied from 0.5 to 6% geographically. The study indicated that, on average, thoron contributes ∼3% of the radiation dose due to indoor radon and thoron exposure in Canada. Even though the estimated average thoron concentration of 9 Bq m(-3) (population weighted) in Canada is low, the average radon concentration of 96 Bq m(-3) (population weighted) is more than double the worldwide average indoor radon concentration. It is clear that continued efforts are needed to further reduce the exposure and effectively reduce the number of lung cancers caused by radon.

  19. Origin of radon concentration of Csalóka Spring in the Sopron Mountains (West Hungary).

    PubMed

    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. PMID:26476411

  20. Origin of radon concentration of Csalóka Spring in the Sopron Mountains (West Hungary).

    PubMed

    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.

  1. Determination of radon level and radon effective dose rate using SSNTD in dwellings in the Bathinda district of Punjab, India.

    PubMed

    Mehra, R; Badhan, K

    2012-11-01

    The problem of indoor radon has attracted a great deal of attention worldwide as radon is the largest contributor to the total natural radiation dose. The dwellings belonging to the Bathinda district of Punjab, India, are investigated for the yearly average of indoor radon concentrations using solid-state nuclear track detectors. The annual average indoor radon values in the study area vary from 122.30 to 147.10 Bq m(-3), which is well within the recommended action level given by the International Commission on Radiological Protection. The calculated lifetime fatality risk values vary from 1.61 to 1.94. The seasonal variations and the contribution of building materials and ventilation conditions to the indoor radon in dwellings are also discussed. PMID:22927649

  2. Hazardous indoor CO2 concentrations in volcanic environments.

    PubMed

    Viveiros, Fátima; Gaspar, João L; Ferreira, Teresa; Silva, Catarina

    2016-07-01

    Carbon dioxide is one of the main soil gases released silently and permanently in diffuse degassing areas, both in volcanic and non-volcanic zones. In the volcanic islands of the Azores (Portugal) several villages are located over diffuse degassing areas. Lethal indoor CO2 concentrations (higher than 10 vol %) were measured in a shelter located at Furnas village, inside the caldera of the quiescent Furnas Volcano (S. Miguel Island). Hazardous CO2 concentrations were detected not only underground, but also at the ground floor level. Multivariate regression analysis was applied to the CO2 and environmental time series recorded between April 2008 and March 2010 at Furnas village. The results show that about 30% of the indoor CO2 variation is explained by environmental variables, namely barometric pressure, soil water content and wind speed. The highest indoor CO2 concentrations were recorded during bad weather conditions, characterized by low barometric pressure together with rainfall periods and high wind speed. In addition to the spike-like changes observed on the CO2 time series, long-term oscillations were also identified and appeared to represent seasonal variations. In fact, indoor CO2 concentrations were higher during winter period when compared to the dry summer months. Considering the permanent emission of CO2 in various volcanic regions of the world, CO2 hazard maps are crucial and need to be accounted by the land-use planners and authorities. PMID:27155095

  3. Hazardous indoor CO2 concentrations in volcanic environments.

    PubMed

    Viveiros, Fátima; Gaspar, João L; Ferreira, Teresa; Silva, Catarina

    2016-07-01

    Carbon dioxide is one of the main soil gases released silently and permanently in diffuse degassing areas, both in volcanic and non-volcanic zones. In the volcanic islands of the Azores (Portugal) several villages are located over diffuse degassing areas. Lethal indoor CO2 concentrations (higher than 10 vol %) were measured in a shelter located at Furnas village, inside the caldera of the quiescent Furnas Volcano (S. Miguel Island). Hazardous CO2 concentrations were detected not only underground, but also at the ground floor level. Multivariate regression analysis was applied to the CO2 and environmental time series recorded between April 2008 and March 2010 at Furnas village. The results show that about 30% of the indoor CO2 variation is explained by environmental variables, namely barometric pressure, soil water content and wind speed. The highest indoor CO2 concentrations were recorded during bad weather conditions, characterized by low barometric pressure together with rainfall periods and high wind speed. In addition to the spike-like changes observed on the CO2 time series, long-term oscillations were also identified and appeared to represent seasonal variations. In fact, indoor CO2 concentrations were higher during winter period when compared to the dry summer months. Considering the permanent emission of CO2 in various volcanic regions of the world, CO2 hazard maps are crucial and need to be accounted by the land-use planners and authorities.

  4. Radon and radon progeny in the Carlsbad Caverns

    SciTech Connect

    Cheng, Y.S.; Chen, T.R.; Wasiolek, P.T; Van Engen, A.

    1997-01-01

    Measurements were made in July 1994 to determine air exchange rate, aerosol characteristics, radon concentrations, and radon progeny activity size distributions in the Carlsbad Caverns. The measured radon concentrations were stable at a level of 1821{+-}55 Bq m{sup -3}(mean {+-}SD). Using a SF{sub 6} trace gas method, it was determined that stagnant air in the Caverns was exchanged once every 18 days. The stagnant air was a key factor in maintaining stable environmental conditions and radon concentration. The low air exchange and few aerosol sources inside the Caverns also contributed to the low aerosol concentrations of between 200 and 400 cm{sup -3} - orders of magnitude lower than mining, indoor, and outdoor environments. The alpha spectrum showed radon progeny but no thoron progeny. The activity size distribution of radon progeny showed typical bimodal distributions with higher unattached fractions than other natural environments. The high unattached fraction was attributed to the extremely low aerosol concentration. Considering the seasonal variation in radon concentration, the estimated cumulative exposure of 1.65 working level months (WLMs) for a worker spending 2000 h in the Carlsbad Caverns with the observed radon concentration seems high, but it is still below the recommended occupational exposure limit for underground uranium miners. 43 refs., 11 figs., 2 tabs.

  5. Radon levels in underground workplaces: a map of the Italian regions.

    PubMed

    Rossetti, Marta; Esposito, Massimo

    2015-04-01

    The indoor radon exposition is a widely recognised health hazard, so specific laws and regulations have been produced in many countries and so-called radon-risk maps have consequently been produced. In Italy the regulation applies to general workplaces and a national survey was carried out in the 1990s to evaluate the exposure to radon in dwellings. Failing a national coordinated mapping programme, some Italian regions performed a survey to identify radon-prone areas, nevertheless with different methodologies. In this work a national map of the average annual radon concentration levels in underground workplaces, obtained from the results of 8695 annual indoor radon measurements carried out by U-Series laboratory between 2003 and 2010, was presented. Due to underground locations, the mean radon concentration is higher than that from previous map elaborated for dwellings and a significant radon concentration was also found in Regions traditionally considered as low-risk areas.

  6. Characterization of particulate matter concentrations during controlled indoor activities

    NASA Astrophysics Data System (ADS)

    Glytsos, T.; Ondráček, J.; Džumbová, L.; Kopanakis, I.; Lazaridis, M.

    2010-04-01

    Indoor sources have been identified as a major contributor to the increase of particle concentration in indoor environments. The work presented here is a study of the characteristics of particulate matter number size distribution and mass concentration under controlled indoor activities in a laboratory room. The objective is to characterize particulate matter concentrations indoors resulted under the influence of specific sources. Measurements were performed in an empty laboratory (period September-October 2006) using a GRIMM SMPS+C system (particle size range between 11.1 and 1083.3 nm), a DustTrak Aerosol Monitor (TSI) and a P-Trak Ultrafine Particle Counter (TSI). The studied indoor activities included candle burning, hot plate heating, water boiling, onion frying, vacuuming, hair drying, hair spraying, smoking and burning of incense stick. The AMANpsd computer algorithm was used to evaluate the modal structure of measured particle number size distribution data. Furthermore, the change of the particle number size distribution shape under the influence of different emission sources was studied versus time. Finally the particle emission rates were computed. High particle number concentrations were observed during smoking, onion frying, candle burning and incense stick burning. The highest particle mass concentrations were measured during smoking and hair spraying. The shift of the particle size distribution to larger diameters suggests the presence of strong coagulation effect during candle burning, incense stick burning, smoking and onion frying. The size distribution was mainly bimodal during onion frying and candle burning, whereas the size distribution remained unimodal during incense stick burning and smoking experiments.

  7. Indoor ozone concentrations: Ventilation rate impacts and mechanisms of outdoor concentration attenuation

    SciTech Connect

    Cano-Ruiz, J.A.; Modera, M.P.; Nazaroff, W.W.

    1992-07-01

    The classification of outdoor (ambient) air as fresh for the purposes of ventilation is not always appropriate, particularly in urban areas. In many cities of the world, urban air frequently violates health-based air quality standards due to high ozone concentrations. The degree of protection from exposure to ozone offered by the indoor environment depends on the relationship between indoor and outdoor ozone levels. Existing concentration data indicates that indoor/outdoor ozone ratios range between 10 and 80%. This paper analyzes several of the key issues influencing indoor ozone concentrations, including: (1) the degree of penetration of outdoor ozone indoors, (2) removal within the indoor environment (removal at surfaces and within air distribution systems), and (3) the correlation in time between outdoor ozone levels and ventilation rates. A model for calculating the degree of ozone removal in typical building leaks and air distribution systems is described and applied to a range of typical cases. This model indicates that the degree of removal is minimal for most wooden building cracks, but could be significant in leaks in concrete or brick structures, and is strongly dependent on the lining material for air distribution systems. Indoor ozone exposure estimates based on hourly outdoor ozone monitoring data and hour-by-hour weather-based simulations of infiltration rates and building operation are reported for a few residential scenarios. These estimates serve as a basis for exploring the impact of energy-efficient ventilation strategies on indoor ozone exposures.

  8. Air cleaning and radon decay product mitigation

    SciTech Connect

    Hopke, P.K. ); Li, C.S. . John B. Pierce Foundation Lab.); Ramamurthi, M. )

    1990-01-01

    We evaluated air cleaning as a means to mitigate risks arising from exposure to indoor radon progeny in several single-family houses in the northeastern United States, using a new, automated, semi-continuous activity-weighted size distribution measurement system. Measurements included radon concentration, condensation nuclei count, and activity-weighted size distribution of radon decay products. Measurements were made with and without the air cleaning system operating. The influence of particles generated by various sources common to normal indoor activities on radon progeny behavior was evaluated. Aerosols were generated by running water in a shower, burning candles, smoking cigarettes, vacuuming, opening doors, and cooking. Both a filtration unit and an electrostatic precipitator were evaluated. Using a room model, the changes in attachment rates, average attachment diameters, and deposition rates of the unattached'' fraction with and without the air cleaning systems were calculated. The air cleaner typically reduced the radon progeny concentrations by 50 to 60%.

  9. Air cleaning and radon decay product mitigation

    SciTech Connect

    Hopke, P.K.; Li, C.S.; Ramamurthi, M.

    1990-12-31

    We evaluated air cleaning as a means to mitigate risks arising from exposure to indoor radon progeny in several single-family houses in the northeastern United States, using a new, automated, semi-continuous activity-weighted size distribution measurement system. Measurements included radon concentration, condensation nuclei count, and activity-weighted size distribution of radon decay products. Measurements were made with and without the air cleaning system operating. The influence of particles generated by various sources common to normal indoor activities on radon progeny behavior was evaluated. Aerosols were generated by running water in a shower, burning candles, smoking cigarettes, vacuuming, opening doors, and cooking. Both a filtration unit and an electrostatic precipitator were evaluated. Using a room model, the changes in attachment rates, average attachment diameters, and deposition rates of the ``unattached`` fraction with and without the air cleaning systems were calculated. The air cleaner typically reduced the radon progeny concentrations by 50 to 60%.

  10. Determination of radon concentration levels in well water in Konya, Turkey.

    PubMed

    Erdogan, M; Eren, N; Demirel, S; Zedef, V

    2013-10-01

    Radon ((222)Rn) measurements were undertaken in 16 samples of well water representing different depths and different types of aquifers found at the city centre of Konya, Central Turkey. The radon activity concentrations of the well water samples collected in the spring and summer seasons of 2012 were measured by using the radon gas analyser (AlphaGUARD PQ 2000PRO). The radon concentrations for spring and summer seasons are 2.29 ± 0.17 to 27.25 ± 1.07 and 1.44 ± 0.18 to 27.45 ± 1.25 Bq l(-1), respectively. The results at hand revealed that the radon concentration levels of the waters strictly depend on the seasons and are slightly variable with depth. Eleven of the 16 well water samples had radon concentration levels below the safe limit of 11.11 Bq l(-1) recommended by the United States Environmental Protection Agency. However, all measured radon concentration levels are well below the 100 Bq l(-1) safe limit declared by the World Health Organisation. The doses resulting from the consumption of these waters were calculated. The calculated minimum and maximum effective doses are 0.29 and 5.49 µSv a(-1), respectively. PMID:23595410

  11. Compilation of geogenic radon potential map of Pest County, Hungary

    NASA Astrophysics Data System (ADS)

    Szabó, K. Zs.; Pásztor, L.; Horváth, Á.; Bakacsi, Zs.; Szabó, J.; Szabó, Cs.

    2010-05-01

    222Rn and its effect on the human health have recently received major importance in environmental studies. This natural radioactive gas accounts for about 9% of lung cancer death and about 2% of all deaths from cancer in Europe due to indoor radon concentrations. It moves into the buildings from the natural decay chain of uranium in soils, rocks and building materials. Radon mapping regionalizes the average hazard from radon in a selected area as a radon risk map. Two major methods (concerning the applied radon data) have been used for mapping. One uses indoor radon data whereas the other is based on soil gas radon data. The outputs of the second approach are the geogenic radon potential maps. The principal objective of our work is to take the first step in geogenic radon mapping in Hungary. Soil samples collected in Pest County (Central Region of Hungary) in the frame of a countrywide soil survey (Soil Information and Monitoring System) were studied to have empirical information of the potential radon risk. As the first two steps radium concentration of soil samples, collected at 43 locations sampling soil profiles by genetic horizons from the surface level down to 60-150 cm, were determined using HPGe gamma-spectroscopy technique, as well as measurement of radon exhalation on the soil samples were carried out applying closed radon accumulation chamber coupled with RAD7 radon monitor detector. From these data the exhalation coefficient was calculated, which shows how many percent of the produced radon can come out from the sample. This rate strongly depends on the depth: at circa 100 cm a drastic decrease have been noticed, which is explained by the change in soil texture. The major source of indoor radon is the soil gas radon concentration (Barnet et al., 2005). We estimated this value from the measured radon exhalation and calculated soil porosity and density. The soil gas radon concentration values were categorized after Kemski et al. (2001) and then the

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

    PubMed

    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. PMID:17196309

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

    PubMed

    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.

  14. Using soil gas radon and geology to estimate regional radon potential

    USGS Publications Warehouse

    Reimer, G.M.

    1992-01-01

    Two important parameters have been identified in order to estimate the radon potential of a region. They are the soil gas radon concentration and the geological rock type from which soils are derived. A simple soil gas collection and analytical technique has been developed to provide information on soil gas radon concentrations. The application of these techniques has demonstrated a clear relationship between the estimate of the radon potential and indoor radon measurements. This information is particularly important when evaluating the radon potential of areas that will be subject to population expansion in the future. Other factors, such as gamma radiation measurements and soil permeability can be included to improve the estimate of radon potential, but geology and soil gas measurements are the most important factors. Although this approach is useful for regional estimates, it can also be used for site-specific evaluations.

  15. Dependence of indoor-pollutant concentrations on sources, ventilation rates, and other removal factors

    SciTech Connect

    Nero, A.V. Jr.; Grimsrud, D.T.

    1983-08-02

    The behavior of several classes of chemical and physical pollutants include emissions from combustion appliances, radon and its progeny, formaldehyde, and other organic compounds. Current research at Lawrence Berkeley Laboratory is described and research needs in the area of indoor air quality is pointed out. (ACR)

  16. Interpretation of radon concentration in the Serrazzano zone of the Larderello geothermal field

    SciTech Connect

    Semprini, L.; Kruger, P.; D'Amore, F.

    1982-01-01

    Wellhead concentrations of radon were made at 22 wells in the south-west region of the Larderello geothermal fields by two analytical methods, a field measurement and a laboratory measurement. The radon concentrations were correlated with average specific volume of superheated steam for each well estimated from available thermodynamic parameters of the reservoir. The correlation was improved by adjusting the specific volume of steam by a mass steam saturation value calculated at the boiling front from chemical fluid composition for each well by a method developed by D'Amore and Celati. A compressible flow model for radon transport developed by Sakakura et al. was also tested. The results confirm that radon behavior in geothermal systems is characterized by thermodynamic conditions in the reservoir. In the Serrazzano zone, abnormally high values of radon concentration with respect to estimated specific volume in four of the 22 wells were observed in an area of proposed low permeability. The high values may also result from higher emanating power or lower porosity in this zone. A cross-section normal to the zone of low permeability between the two basins shows a similar radon profile as noted in a Geysers production zone. A comparison of these data with the set obtained in 1976 by D'Amore shows relatively constant radon concentration despite several wells having large variations in gas/steam ratios.

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

    PubMed Central

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

    2016-01-01

    Because 222Rn is a progeny of 238U, 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. PMID:26472478

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

    PubMed

    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. PMID:26472478

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

    PubMed

    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.

  20. Determination of the minimum measurement time for estimating long-term mean radon concentration.

    PubMed

    Janik, M; Łoskiewicz, J; Tokonami, S; Kozak, K; Mazur, J; Ishikawa, T

    2012-11-01

    Radon measurements, as do any measurements, include errors in their readings. The relative values of such errors depend principally on the measurement methods used, the radon concentration to be measured and the duration of the measurements. Typical exposure times for radon surveys using passive detectors [nuclear track detectors, activated charcoal, electrostatic (E-perm), etc.)] may extend from a few days to months, whereas, in the case of screening methods utilising active radon monitors (AlphaGUARD, RAD7, EQF, etc.), the measurements may be completed quickly within a few hours to a few days. Thus, the latter may have relatively large error values, which affect the measurement accuracy significantly compared with the former measurements made over long time periods. The method presented in this paper examines the uncertainty of a short-term radon measurement as an estimate of the long-term mean and suggests a minimum measurement time to achieve a given margin of uncertainty of that estimate. PMID:22923240

  1. CR-39 detector compared with Kodalpha film type (LR115) in terms of radon concentration

    NASA Astrophysics Data System (ADS)

    Dwaikat, Nidal; Safarini, Ghassan; El-hasan, Mousa; Iida, Toshiyuki

    2007-05-01

    CR-39 detectors and Kodalpha film type (LR115) were compared in terms of radon radiation concentration. Thirteen CR-39 detectors with the same number of Kodalpha film type (LR115) were used in this study. The correlation factor between the radon concentrations, obtained by the two groups of detectors was found to be 0.99. Detector time efficiency (DTE) was calculated for both types of detectors. DTE of Kodalpha film is larger than that of CR-39 detector and this indicates that LR115 is more efficient and sensitive for radon radiation than CR-39 detector.

  2. Home interventions are effective at decreasing indoor nitrogen dioxide concentrations

    PubMed Central

    Paulin, L. M.; Diette, G. B.; Scott, M.; McCormack, M. C.; Matsui, E. C.; Curtin-Brosnan, J.; Williams, D. L.; Kidd-Taylor, A.; Shea, M.; Breysse, P. N.; Hansel, N. N.

    2016-01-01

    Nitrogen dioxide (NO2), a by-product of combustion produced by indoor gas appliances such as cooking stoves, is associated with respiratory symptoms in those with obstructive airways disease. We conducted a three-armed randomized trial to evaluate the efficacy of interventions aimed at reducing indoor NO2 concentrations in homes with unvented gas stoves: (i) replacement of existing gas stove with electric stove; (ii) installation of ventilation hood over existing gas stove; and (iii) placement of air purifiers with high-efficiency particulate air (HEPA) and carbon filters. Home inspection and NO2 monitoring were conducted at 1 week pre-intervention and at 1 week and 3 months post-intervention. Stove replacement resulted in a 51% and 42% decrease in median NO2 concentration at 3 months of follow-up in the kitchen and bedroom, respectively (P = 0.01, P = 0.01); air purifier placement resulted in an immediate decrease in median NO2 concentration in the kitchen (27%, P < 0.01) and bedroom (22%, P = 0.02), but at 3 months, a significant reduction was seen only in the kitchen (20%, P = 0.05). NO2 concentrations in the kitchen and bedroom did not significantly change following ventilation hood installation. Replacing unvented gas stoves with electric stoves or placement of air purifiers with HEPA and carbon filters can decrease indoor NO2 concentrations in urban homes. PMID:24329966

  3. Radon exhalation rate of some building materials used in Egypt.

    PubMed

    Maged, A F; Ashraf, F A

    2005-09-01

    Indoor radon has been recognized as one of the health hazards for mankind. Common building materials used for construction of houses, which are considered as one of the major sources of this gas in indoor environment, have been studied for exhalation rate of radon. Non-nuclear industries, such as coal fired power plants or fertilizer production facilities, generate large amounts of waste gypsum as by-products. Compared to other building materials waste gypsum from fertilizer production facilities (phosphogypsum) shows increased rates of radon exhalation. In the present, investigation solid state alpha track detectors, CR-39 plastic detectors, were used to measure the indoor radon concentration and the radon exhalation rates from some building materials used in Egypt. The indoor radon concentration and the radon exhalation rate ranges were found to be 24-55 Bq m(-3 )and 11-223 mBq m(-2) h(-1), respectively. The effective dose equivalent range for the indoor was found 0.6-1.4 mSv y(-1). The equilibrium factor between radon and its daughters increased with the increase of relative humidity.

  4. Radon progeny size distributions and enhanced deposition effects from high radon concentrations in an enclosed chamber.

    PubMed

    Leonard, Bobby E

    2004-01-01

    Prior work studying radon progeny in a small enclosed chamber found that at high (222)Rn concentrations an enhanced surface deposition was observed. Subsequent measurements for unfiltered air showed minimal charged particle mobility influence. Progeny particle size measurements reported here, performed at the US Department of Energy Environmental Measurement Laboratory (now with Home Security Department), using the EML graded screen array (GSA) system show in unfiltered air that the high (222)Rn levels causes a reduction in the attached (218)Po progeny airborne particulates and formation of additional normal sized unattached ( approximately 0.80 nm) and also even smaller (218)Po below 0.50 nm. At a (222)Rn level of 51 kBq m(-3), 73% of all (218)Po are of a mean particle diameter of about 0.40 +/- 0.02 nm. At this (222)Rn level, the ratio of (218)Po to (222)Rn airborne concentrations is reduced significantly from the concentration ratio at low (222)Rn levels. Similar reductions and size reformations were observed for the (214)Pb and (214)Bi/Po progeny. The particle size changes are further confirmed using the plateout rates and corresponding deposition velocities. The Crump and Seinfeld deposition theory provides the corresponding particle diffusion coefficients. With the diffusion coefficient to ultrafine clustered particle diameter correlation of Ramamurthi and Hopke, good agreement is obtained between EML GSA and deposition velocity data down to 0.40 nm. Strong evidence is presented that the progeny size reduction is due to, as a result of air ionization, the increased neutralization rate (primarily from electron scavenging of OH molecules) of the initially charged progeny. This is shown to increase with the (1/2) power of (222)Rn concentration and relative humidity as well as increased air change rate in the chamber. These results imply that at (222)Rn levels above 50 kBq m(-3), at relative humidity of 52%, a considerable reduction in lung dose could occur from

  5. PARAMETRIC ANALYSIS OF THE INSTALLATION AND OPERATING COSTS OF ACTIVE SOIL DEPRESSURIZATION SYSTEMS FOR RESIDENTIAL RADON MITIGATION

    EPA Science Inventory

    The report gives results of a recent analysis showing that cost- effective indoor radon reduction technology is required for houses with initial radon concentrations < 4 pCi/L, because 78-86% of the national lung cancer risk due to radon is associated with those houses. ctive soi...

  6. Determination of radon and radium concentrations in drinking water samples around the city of Kutahya.

    PubMed

    Sahin, Latife; Cetinkaya, Hakan; Murat Saç, Müslim; Içhedef, Mutlu

    2013-08-01

    The concentration of radium and radon has been determined in drinking water samples collected from various locations of Kutahya city, Turkey. The water samples are taken from public water sources and tap water, with the collector chamber method used to measure the radon and radium concentration. The radon concentration ranges between 0.1 and 48.6±1.7 Bq l(-1), while the radium concentration varies from a minimum detectable activity of <0.02-0.7±0.2 Bq l(-1) in Kutahya city. In addition to the radon and radium levels, parameters such as pH, conductivity and temperature of the water, humidity, pressure, elevation and the coordinates of the sampling points have also been measured and recorded. The annual effective dose from radon and radium due to typical water usage has been calculated. The resulting contribution to the annual effective dose due to radon ingestion varies between 0.3 and 124.2 μSv y(-1); the contribution to the annual effective dose due to radium ingestion varies between 0 and 143.3 μSv y(-1); the dose contribution to the stomach due to radon ingestion varies between 0.03 and 14.9 μSv y(-1). The dose contribution due to radon inhalation ranges between 0.3 and 122.5 μSv y(-1), assuming a typical transfer of radon in water to the air. For the overwhelming majority of the Kutahya population, it is determined that the average radiation exposure from drinking water is less than 73.6 µSv y(-1).

  7. Radon-hazard potential of Utah

    SciTech Connect

    Black, B.D.; Solomon, B.J. )

    1993-04-01

    Radon is a naturally occurring radioactive gas formed by decay of uranium, and occurs in nearly all geologic materials. Although radon has been shown to be a significant cause of lung cancer in miners, the health hazard from accumulation of radon gas in buildings has only recently been recognized. Indoor-radon hazards depend on both geologic and non-geologic factors. Although non-geologic factors such as construction type, weather, and lifestyles are difficult to measure, geologic factors such as uranium concentration, soil permeability, and depth to ground water can be quantified. Uranium-enriched geologic materials, such as black shales, marine sandstones, and certain granitic, metamorphic, and volcanic rocks, are generally associated with a high radon-hazard potential. Impermeable soil or shallow ground water impedes radon movement and is generally associated with a low radon-hazard potential. A numerical rating system based on these geologic factors has been developed to map radon-hazard potential in Utah. A statewide map shows that the radon-hazard potential of Utah is generally moderate. Assessments of hazard potential from detailed field investigations correlate well with areas of this map. Central Utah has the highest radon-hazard potential, primarily due to uranium-enriched Tertiary volcanic rocks. The radon-hazard potential of eastern Utah is moderate to high, but is generally restricted by low uranium levels. Western Utah, where valley basins with impermeable soils and shallow ground water are common, has the lowest radon-hazard potential.

  8. A means to make open-face charcoal detectors respond correctly to varying concentration radon fields

    SciTech Connect

    Distenfeld, C.H.

    1995-12-31

    Ronca-Battista and D. Gray 87, outlined the poor response of open-face charcoal detectors to varying concentration radon fields. At worst, for two day exposures with open-face charcoal canisters, their Table 4 indicated a 75% under-response for radon concentrations that were 10 times higher during the first day of two, 10:1. TCS has made similar measurements with open-faced and diffusion barrier detectors in 20:1, 1:20, and 1:1 fields. For the worst case 20:1, measurements indicate TCS two day open-face canisters under respond by 50%, while the Cohen and TCS diffusion barrier devices under responded by about 37%. The reasons for the under response are radon diffusion out of the charcoal due to the forces of lower concentration during the second half of the exposure, and uncompensated radioactive decay of radon gas.

  9. Predictive analysis of shaft station radon concentrations in underground uranium mine: A case study.

    PubMed

    Zhao, Guoyan; Hong, Changshou; Li, Xiangyang; Lin, Chunping; Hu, Penghua

    2016-07-01

    This paper presented a method for predicting shaft station radon concentrations in a uranium mine of China through theoretical analysis, mathematical derivation and Monte-Carlo simulation. Based upon the queuing model for tramcars, the average waiting time of tramcars and average number of waiting tramcars were determined, which were further used in developing the predictive model for calculating shaft station radon concentrations. The results exhibit that the extent of variation of shaft station radon concentration in the case study mine is not significantly affected by the queuing process of tramcars, and is always within the allowable limit of 200 Bq m(-3). Thus, the empirical limit of 100,000 T annual ore-hoisting yields has no value in ensuring radiation safety for this mine. Moreover, the developed model has been validated and proved useful in assessing shaft station radon levels for any uranium mine with similar situations.

  10. Comparison of indoor and outdoor concentrations of CO at a public school. Evaluation of an indoor air quality model

    NASA Astrophysics Data System (ADS)

    Chaloulakou, A.; Mavroidis, I.

    A field study was carried out to investigate the internal and external carbon monoxide (CO) concentration levels of a public school building in Athens, Greece. Simultaneous measurements of indoor and outdoor CO concentrations were conducted using a non-dispersive infrared analyzer. Measurements of mean hourly CO concentrations inside and outside the sampling room were conducted on a 24-h basis for 13 consecutive days during May and June 1999 and for 14 consecutive days during December 1999. The aim of the study was to investigate the attenuation pattern of external pollution levels within the building. The diurnal concentration variations reported for different days during the week show that indoor CO concentrations are in general lower than the respective outdoor levels, and that the morning peaks of indoor concentrations show a delay of 1 h or less compared to the morning peaks of outdoor concentrations. The measured indoor to outdoor concentration ratios show a seasonal variation. An indoor air quality model for the prediction of indoor concentration levels developed by Hayes (J. Air Pollut. Control Assoc. 39 (11) (1989) 1453; J. Air Waste Manage. Assoc. 41 (2) (1991) 161) is coded as a computer program and evaluated using the experimental data. The model results are in good agreement with the indoor concentration measurements, although in some cases the model cannot respond adequately to sharp outdoor concentration changes. The ratio between measured and predicted daily maximum indoor concentration ranges between 0.88 and 1.23. The regression curve between predicted by the model and measured hourly indoor concentrations, for a continuous period of 96 h, has a slope of 0.64 and a coefficient of determination ( R2) of 0.69.

  11. Geological and geochemical factors affecting the radon concentration in homes in Cornwall and Devon, UK.

    PubMed

    Ball, T K; Miles, J C

    1993-03-01

    Recently collected data for radon levels in houses in Devon and Cornwall are compared with geological and geochemical information. The region is underlain by granites intruded into folded sedimentary rocks. The highest incidence of affected houses is on granites. The granites are characterised by moderate uranium concentrations, a deep weathering profile and uranium in mineral phase which is easily weathered. However, while the uranium may be removed, radium, the immediate precursor of radon, can remain in situ. Radon is emanated easily from the host rock, and high values of radon in ground and surface waters and soil gases have been detected. The granite areas are also characterised by high values of uranium in stream sediments and waters. In contrast, other zones of high uranium in stream sediment samples do not necessarily exhibit high house radon concentrations, especially when underlain by relatively impermeable rocks. Permeable ground can give rise to high incidences, of affected houses despite having uranium levels close to the crustal abundance. It is concluded that the most efficient method of identifying zones of high radon potential is the soil gas radon survey.

  12. Radon concentrations in homes in an area of dolomite bedrock: Door County, Wisconsin

    SciTech Connect

    Hawk, K.; Stieglitz, R.D.; Norman, J.C.

    1993-12-31

    A statewide survey by the Wisconsin Department of Health and Social Services with U.S.E.P.A. assistance reported an anomalously high percentage of homes in Door County with radon concentrations in excess of 20 pCi/L. The results were of interest because the county is underlain by marine sedimentary rocks rather than the igneous and metamorphic crystalline types usually associated with elevated radon concentrations. A voluntary population of 55 homes was tested for radon using activated charcoal canisters. This population was also asked to provide questionnaire response data on family, home, and socioeconomic aspects. The data were separated into socioeconomic, energy efficiency, radon access, and karst level categories and statistically analyzed. A subpopulation was selected from the larger population for detailed site investigation, which included additional in-home air testing and, at some sites, water supply analysis and in-ground testing for radon. The field investigations collected information on the geology, soil, topography, and home construction and use. The results of the investigation verified and characterized the radon occurrences in Door County. The presence or absence of karst features is shown to be statistically significant to radon levels. 23 refs., 5 figs., 3 tabs.

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

    SciTech Connect

    York, E.L.

    1995-12-31

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

  14. A survey of 222Rn concentrations in dwellings of the town of Metsovo in north-western Greece.

    PubMed

    Ioannides, K G; Stamoulis, K C; Papachristodoulou, C A

    2000-12-01

    A radon survey has been carried out of indoor radon concentrations in dwellings located in the town of Metsovo, in north-western Greece. To measure indoor radon concentrations, CR-39 detectors were installed in randomly selected houses and were exposed for about 3 mo, during summer and winter. Gamma spectroscopy measurements of the soil's radium content also were performed. The indoor radon concentration levels varied from 17.6 to 750.4 Bq m(-3), while the radium concentration of soil varied from 4.9 to 97.1 Bq m(-3). Seasonal variation of the radon levels and the influence of house features and soil are discussed.

  15. Constraints for Using Radon-in-Water Concentrations as an Indicator for Groundwater Discharge into Surface Water Bodies

    NASA Astrophysics Data System (ADS)

    Petermann, Eric; Schubert, Michael

    2015-04-01

    The radon (222-Rn) activity concentration of surface water is a favourable indicator for the detection of groundwater discharge into surface water bodies since radon is highly enriched in groundwater relative to surface waters. Hence, positive radon-in-water anomalies are interpreted as groundwater discharge locations. For this approach, usually, radon time-series are recorded along transects in near-surface waters. Time-series of radon-in-water concentration are commonly measured by permanent radon extraction from a water pump stream and continuous monitoring of the resulting radon-in-air concentration by means of a suitable radon detector. Radon-in-water concentrations are derived from the recorded radon-in-air signal by making allowances for water/air partitioning of radon. However, several constraints arise for this approach since undesirable factors are influencing the radon-in-water concentration. Consequently, corrections are required to remove the effect of these undesirable factors from the radon signal. First, an instrument inherent response delay between actual changes in the radon-in-water concentration and the related radon-in-air signal was observed during laboratory experiments. The response delay is due to (i) the water/air transfer kinetics of radon and (ii) the delayed decay equilibrium between radon and its progeny polonium (218-Po), which is actually being measured by most radon-in-air monitors. We developed a physical model, which considers all parameters that are responsible for the response delay. This model allows the reconstruction of radon-in-water time-series based on radon-in-air records. Second, on a time-scale of several hours the tidal stage is known as a major driver for groundwater discharge fluctuations due to varying hydraulic gradients between groundwater and surface water during a tidal cycle. Consequently, radon-in-water time-series that are detected on tidal coasts are not comparable among each other without normalization

  16. The Distribution of Exposure to Radon: Effects of Population Mobility

    SciTech Connect

    Gadgil, A.J.; Rein, S.; Nero, A.V.; Wollenberg Jr., H.A.

    1993-01-01

    The distribution of population exposures to radon, rather than the distribution of indoor radon concentrations, determines the fraction of population exposed to exceptionally high risk from radon exposures. Since this fraction at high risk has prompted the development of public policies on radon, it is important to first determine the magnitude of this fraction, and then how it much would decrease with different implementation program options for radon mitigation. This papers presents an approach to determining the distribution of population exposures to radon from public domain data, and illustrates it with application to the state of Minnesota. During this work, we are led to define a radon entry potential index which appears useful in the search for regions with high radon houses.

  17. Radon Concentration in Groundwater in the Central Region of Gyeongju, Korea - 13130

    SciTech Connect

    Lee, Jung Min; Lee, A. Rim; Park, Chan Hee; Moon, Joo Hyun

    2013-07-01

    Radon is a naturally occurring radioactive gas that is a well known cause of lung cancer through inhalation. Nevertheless, stomach cancer can also occur if radon-containing water is ingested. This study measured the radon concentration in groundwater for drinking or other domestic uses in the central region of Gyeongju, Korea. The groundwater samples were taken from 11 points chosen from the 11 administrative districts in the central region of Gyeongju by selecting a point per district considering the demographic distribution including the number of tourists who visit the ancient ruins and archaeological sites. The mean radon concentrations in the groundwater samples ranged from 14.38 to 9050.73 Bq.m{sup -3}, which were below the recommendations by the U.S. EPA and WHO. (authors)

  18. Radon and radium concentration in water from North-West of Romania and the estimated doses.

    PubMed

    Moldovan, M; Benea, V; Niţă, D C; Papp, B; Burghele, B D; Bican-Brişan, N; Cosma, C

    2014-11-01

    In the present study, the measurements of radon were carried out using the LUK-VR system based on radon gas measurements with Lucas cells. The radium concentration in water was determined, with the same device, immediately after was established the radon equilibrium with radium. The results presented here are from a survey carried out in the N-W region of Transylvania (Romania) in which were investigated the radon concentrations in natural (spring, well and surface) and drinking (tap) waters. The results showed radon concentrations within the range of 0.4-187.3 Bq l(-1) with an average value of 15.9 Bq l(-1) whereas radium concentration varied between 0.05 and 0.825 Bq l(-1) with an average value of 0.087 Bq l(-1) for all types of water covered within this survey. The corresponding annual effective ingestion dose due to radon and radium from water was determined from drinking water used by the population inhabiting the area.

  19. Radon and radium concentration in water from North-West of Romania and the estimated doses.

    PubMed

    Moldovan, M; Benea, V; Niţă, D C; Papp, B; Burghele, B D; Bican-Brişan, N; Cosma, C

    2014-11-01

    In the present study, the measurements of radon were carried out using the LUK-VR system based on radon gas measurements with Lucas cells. The radium concentration in water was determined, with the same device, immediately after was established the radon equilibrium with radium. The results presented here are from a survey carried out in the N-W region of Transylvania (Romania) in which were investigated the radon concentrations in natural (spring, well and surface) and drinking (tap) waters. The results showed radon concentrations within the range of 0.4-187.3 Bq l(-1) with an average value of 15.9 Bq l(-1) whereas radium concentration varied between 0.05 and 0.825 Bq l(-1) with an average value of 0.087 Bq l(-1) for all types of water covered within this survey. The corresponding annual effective ingestion dose due to radon and radium from water was determined from drinking water used by the population inhabiting the area. PMID:25031036

  20. Variations of soil radon concentrations along Chite fault in Aizawl district, Mizoram, India.

    PubMed

    Singh, Sanjay; Jaishi, Hari Jaishi; Tiwari, Raghavendra Prasad; Tiwari, Ramesh Chandra

    2014-11-01

    The present study concerns measurements of radon emissions from soil carried out during March to July 2013 at Chite fault in Aizawl district, Mizoram, India. In this study, continuous radon monitoring in soil was done by using LR-115 type II nuclear track detector (Kodak-Pathe, France make), and the exposed films were replaced weekly. A negative correlation coefficient (-0.47) between radon concentration and barometric pressure was found during the investigation period. The average radon concentration was observed to be 1785.71 Bq m(-3) with a standard deviation of 633.07 Bq m(-3). The maximum and minimum values of radon concentration during this period were found to be 3693.88 and 904.76 Bq m(-3), respectively. An anomalous increase in radon concentration was observed on 112th day (i.e. on 14 June 2013) during the investigation period just 1 d prior to the event of M 3.5, which occurred within 120-km distance from the monitoring site. PMID:24996920

  1. Predicting indoor pollutant concentrations, and applications to air quality management

    SciTech Connect

    Lorenzetti, David M.

    2002-10-01

    Because most people spend more than 90% of their time indoors, predicting exposure to airborne pollutants requires models that incorporate the effect of buildings. Buildings affect the exposure of their occupants in a number of ways, both by design (for example, filters in ventilation systems remove particles) and incidentally (for example, sorption on walls can reduce peak concentrations, but prolong exposure to semivolatile organic compounds). Furthermore, building materials and occupant activities can generate pollutants. Indoor air quality depends not only on outdoor air quality, but also on the design, maintenance, and use of the building. For example, ''sick building'' symptoms such as respiratory problems and headaches have been related to the presence of air-conditioning systems, to carpeting, to low ventilation rates, and to high occupant density (1). The physical processes of interest apply even in simple structures such as homes. Indoor air quality models simulate the processes, such as ventilation and filtration, that control pollutant concentrations in a building. Section 2 describes the modeling approach, and the important transport processes in buildings. Because advection usually dominates among the transport processes, Sections 3 and 4 describe methods for predicting airflows. The concluding section summarizes the application of these models.

  2. Instrumentation for a radon research house

    SciTech Connect

    Nazaroff, W.W.; Revzan, K.L.; Robb, A.W.

    1981-07-01

    A highly automated monitoring and control system for studying radon and radon-daughter behavior in residences has been designed and built. The system has been installed in a research house, a test space contained in a two-story wood-framed building, which allows us to conduct controlled studies of (1) pollutant transport within and between rooms, (2) the dynamics of radon daughter behavior, and (3) techniques for controlling radon and radon daughters. The system's instrumentation is capable of measuring air-exchange rate, four-point radon concentration, individual radon daughter concentrations, indoor temerature and humidity, and outdoor weather parameters (temperature, humidity, modules, wind speed, and wind direction). It is also equipped with modules that control the injection of radon and tracer gas into the test space, the operation of the forced-air furnace, the mechanical ventilation system, and the mixing fans located in each room. A microcomputer controls the experiments and records the data on magnetic tape and on a printing terminal. The data on tape is transferred to a larger computer system for reduction and analysis. In this paper we describe the essential design and function of the instrumentation system, as a whole, singling out those components that measure ventilation rate, radon concentration, and radon daughter concentrations.

  3. Analysis of outdoor radon progeny concentration measured at the Spanish radioactive aerosol automatic monitoring network.

    PubMed

    Arnold, D; Vargas, A; Ortega, X

    2009-05-01

    An analysis of 10-year radon progeny data, provided by the Spanish automatic radiological surveillance network, in relation to meteorology is presented. Results show great spatial variability depending mainly on the station location and thus, the surrounding radon exhalation rate. Hourly averages show the typical diurnal cycle with an early morning maximum and a minimum at noon, except for one mountain station, which shows an inverse behaviour. Monthly averaged values show lower concentrations during months with higher atmospheric instability.

  4. A tentative protocol for measurement of radon availability from the ground

    USGS Publications Warehouse

    Tanner, A.B.

    1988-01-01

    A procedure is being tested in order to determine its suitability for assessing the intrinsic ability of the ground at a particular site to supply radon (222Rn) to a basement structure to be built on the site. The mean migration distance, multiplied by the measured radon concentration gives the "Radon Availability Number' (RAN). Measurements at sites of known indoor radon concentration suggest that RANs below 2 kBq/m2 (5x104 pCi/m2) indicate little chance of elevated indoor radon and RANs above 20 kBq/m2 (5x105 pCi/m2) indicate that elevated indoor radon is likely. The range of uncertainty and the point-to-point and seasonal variations to be expected are under investigation. -from Author

  5. Experimental studies about the ratio between 210Po deposited on surfaces and retrospective indoor 222Rn concentrations.

    PubMed

    Martín Sánchez, A; de la Torre Pérez, J; Ruano Sánchez, A B

    2014-07-01

    Measurements of radon concentration may not be sufficiently representative for the cumulative total exposure suffered by a person throughout his life. Retrospective dosimetry can help estimating from the direct measurement of 210Po (descendant of 222Rn) implanted on surfaces, because this quantity is related (through the conversion factor) with the mean indoor 222Rn concentration existing in a room for long time. This factor depends on multiple variables. Theoretical models can provide some values. Experiments are tedious and very time consuming. The 210Po activity concentration was measured in mirrors, which were previously exposed to 222Rn concentrations under real environmental conditions. This work deals with the preliminary results in two known places (a room and a cave), which have very different characteristics, in order to show experimentally the large differences found in the values of this factor.

  6. Experimental studies about the ratio between 210Po deposited on surfaces and retrospective indoor 222Rn concentrations.

    PubMed

    Martín Sánchez, A; de la Torre Pérez, J; Ruano Sánchez, A B

    2014-07-01

    Measurements of radon concentration may not be sufficiently representative for the cumulative total exposure suffered by a person throughout his life. Retrospective dosimetry can help estimating from the direct measurement of 210Po (descendant of 222Rn) implanted on surfaces, because this quantity is related (through the conversion factor) with the mean indoor 222Rn concentration existing in a room for long time. This factor depends on multiple variables. Theoretical models can provide some values. Experiments are tedious and very time consuming. The 210Po activity concentration was measured in mirrors, which were previously exposed to 222Rn concentrations under real environmental conditions. This work deals with the preliminary results in two known places (a room and a cave), which have very different characteristics, in order to show experimentally the large differences found in the values of this factor. PMID:24729559

  7. Geostatistical simulations for radon