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Sample records for indoor radon levels

  1. 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.

  2. 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.

  3. 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.

  4. 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

  5. A comparative study of the indoor radon level with the radon exhalation rate from soil in Alexandria city.

    PubMed

    Abd El-Zaher, Mohamed

    2013-05-01

    The assessment of the radiological risk related to the inhalation of radon and radon its progeny is based mainly on the integrated measurement of radon in both indoor and outdoor environments. The exhalation of radon from the earth's crust and building materials forms the main source of radon in the indoor environment. This study has been undertaken for the purpose of health risk assessment. In this comparative study, the indoor radon level, radium content, radon exhalation rate and concentration of soil radon are measured using the Can Technique. Soil samples were collected simultaneously from different geological formations of the same area for laboratory measurement of the radon exhalation rate. The radon exhalation rate was measured in the laboratory using LR-115 type II plastic track detectors. The indoor radon concentrations in this study area were found to vary from 44±9 to 132±31 Bq m(-3) with an average of 72±29 Bq m(-3). The seasonal variations of the indoor radon reveal the maximum values in the winter and in summer in different dwellings of Alexandria city. The annual effective dose varies from 0.75 to 2.2 mSv with an average value of 1.34 mSv. The radon exhalation rate was found to vary in the ranges 8.31-233.70×10(-3) Bq kg(-1) h(-1), 0.48-15.37 Bq m(-2) h(-1) with an average 47.97×10(-3) Bq kg(-1) h(-1), (3.14 Bq m(-2) h(-1)). The radium content in soil varies from 3.14 to 39.60 Bq kg(-1) with an average of 11.55 Bq kg(-1). The significance of this study is discussed in details from the point of view of radiation protection.

  6. 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.

  7. Regional variations pattern of indoor radon levels in some areas of Punjab and Haryana.

    PubMed

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

    2008-01-01

    The indoor radon concentration levels and their regional variations pattern, for two consecutive half-year periods, in a wide range of dwellings of some regions of Punjab and Haryana states have been studied. The objective was to find the relation between the variations of indoor radon levels with the sub-soil and local geology, type of building materials utilised in the dwellings of the region. Keeping this in view, indoor radon measurements have been carried out in the dwellings of 30 villages around the Tusham Ring Complex, Bhiwani district, Haryana, known to be composed of acidic volcanics and associated granites, along with 11 villages of Amritsar District, Punjab. The indoor radon concentration in the dwellings around Tusham (Haryana) was found to vary from 120 +/- 95 to 915 +/- 233 Bq m(-3), whereas radon levels varied from 60 +/- 37 to 235 +/- 96 Bq m(-3) for the dwellings studied in Punjab. We believe that local geology including embedded granitic rocks, and sub-soil, as well as building materials having higher radioactive content, is the major contributor for the higher indoor radon levels observed particularly in the dwelling around Tusham Ring complex, where some dwellings are showing higher radon concentrations than the ICRP recommendations. The environmental samples from some areas of Punjab state and around the Tusham Ring Complex of Haryana state have also been analysed for radon exhalation studies. Higher values for radon exhalation rates have been observed for the Tusham's soil/rock specimens, as compared with soil samples of the Amritsar region of Punjab.

  8. 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.

  9. An approach to define potential radon emission level maps using indoor radon concentration measurements and radiogeochemical data positive proportion relationships.

    PubMed

    Drolet, Jean-Philippe; Martel, Richard; Poulin, Patrick; Dessau, Jean-Claude; Lavoie, Denis; Parent, Michel; Lévesque, Benoît

    2013-10-01

    The aim of this paper is to present the first step of a new approach to make a map of radonprone areas showing different potential radon emission levels in the Quebec province. This map is a tool intended to assist the Quebec government in identifying populations with a higher risk of indoor radon gas exposure. This map of radon-prone areas used available radiogeochemical information for the province of Quebec: (1) Equivalent uranium (eU) concentration from airborne surface gamma-ray surveys; (2) uranium concentration measurements in sediments; and (3) bedrock and surficial geology. Positive proportion relationships (PPR) between each individual criterion and the 1417 available basement radon concentrations were demonstrated. It was also shown that those criteria were reliable indicators of radon-prone areas. The three criteria were discretized into 3, 2 and 2 statistically significant different classes respectively. For each class, statistical heterogeneity was validated by Kruskal-Wallis one way analyses of variance on ranks. Maps of radon-prone areas were traced down for each criterion. Based on this statistical study and on the maps of radon-prone areas in Quebec, 18% of the dwellings located in areas with an equivalent uranium (eU) concentration from airborne surface gamma-ray surveys under 0.75 ppm showed indoor radon concentrations above 150 Bq/m3. This percentage increases to 33% when eU concentrations are between 0.75 ppm and 1.25 ppm and exceeds 40% when eU concentrations are above 1.25 ppm. A uranium concentration in sediments above 20 ppm showed an indoor radon concentration geometric mean of 215 Bq/m3 with more than 69% of the dwellings exceeding 150 Bq/m3 or more than 50% of dwellings exceeding the Canadian radon guideline of 200 Bq/m3. It is also shown that the radon emission potential is higher where a uranium-rich bedrock unit is not covered by a low permeability (silt/clay) surficial deposit.

  10. 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.

  11. 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.

  12. 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.

  13. Indoor radon: deadliest pollutant

    SciTech Connect

    Pool, R.

    1988-04-29

    Radon in individual homes may be the greatest source of radiation that people are exposed to during a lifetime. In areas where radon concentrations in homes are high, people may be exposed to more radiation than were the Russian people living in the vicinity of Chernobyl Nuclear Power Plant. Studies indicate that the radon exposure contributes to 5000 to 20,000 deaths per year from lung cancer and that smoking may have a lethal interaction with the radon exposure. One study found an average annual concentration of radon in living spaces of 1.5 picocuries per liter. 7% of U.S. homes were found to have a radon concentration above the 4 picocuries per liter level set by the Environmental Protection Agency, and 1 - 3% of the homes have levels above 8 picocuries. Some ways are described for changing the air pressure in a house so that air is not constantly drawn from the permeable soil where the radon originates.

  14. 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.

  15. 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.

  16. 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).

  17. 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.

  18. 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)

  19. 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).

  20. Indoor radon concentrations in Taiwanese homes

    SciTech Connect

    Hung, I.F.; Yu, C.C.; Tung, C.J. ); Yang, Y.C.; Chou, K.D. )

    1994-10-01

    Many air pollutants may be present in the indoor environment. Commonly reported pollutants are carbon monoxide, nitrogen dioxide, volatile organic compounds, radon and its progeny, asbestos fibers and airborne particles. Among these indoor pollutants, radon and its progeny have been known to increase the risk of lung cancer in the U.S. Various studies also found in general higher concentrations of air pollutants in the indoor environment. It is a serious concern to us because of the long periods of time we spend indoors. In this study, the alpha-track radon monitor was used in the screening of higher risk buildings in Taipei and Hsinchu city. None of the homes in the 32 buildings surveyed in these cities had air concentrations of radon exceeding the action level of 4 pCi/l recommended by the U.S. Environmental Protection Agency. Different sources to indoor radon concentrations are the underlying soil, building materials, outdoor air, water and gaseous fuels. Ventilation of the homes and seasonal variations are major factors of higher radon concentrations. 16 refs., 2 figs., 3 tabs.

  1. Radon level and indoor gamma doses in dwellings of Trabzon, Turkey.

    PubMed

    Kurnaz, A; Küçükömeroğlu, B; Cevik, U; Celebi, N

    2011-10-01

    The seasonal variations of the indoor radon activity concentrations were determined in the 97 dwellings of Trabzon, Turkey. The annual average indoor radon activity concentration varied from 8 to 583 Bq/m³. The average winter/summer ratio of radon activity concentrations was 3.62. The gamma activity concentrations in the soil samples were determined as 41, 38, 443 and 25 Bq/kg for ²²⁶Ra, ²³²Th, ⁴⁰K and ¹³⁷Cs, respectively. The average gamma dose rate in air and the annual effective dose equivalent for outdoor occupancy were calculated as 63 nGy/h and 77 μSv/y, respectively.

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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

  7. Potential health effects of indoor radon exposure.

    PubMed

    Radford, E P

    1985-10-01

    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.

  8. 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??.

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

    PubMed

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

    2014-03-01

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

  10. Indoor radon prediction from soil gas measurements.

    PubMed

    Varley, N R; Flowers, A G

    1998-06-01

    This study of radon levels in southwest England investigates the correlation between indoor and soil gas radon concentrations and considers the influence of geology, meteorological variables, spatial and depth variations. This paper examines the value of soil gas measurements as an indicator of potential indoor radon concentrations and highlights a number of factors that need to be considered. Only a very weak correlation was obtained between the overall 222Rn concentration in soil gas and inside the home. However, for high soil gas concentrations a stronger correlation with the indoor level was observed. Typically, the soil gas concentration was between a factor of 10 and 1,000 times greater than that indoors. Levels as low as 10 kBq m(-3) in the soil could produce an indoor concentration above the UK action level of 200 Bq m(-3). The moisture content and the inhomogeneity of soil permeability were identified as chiefly responsible for any perturbation of a soil gas concentration associated with a particular geology. Alone, measured soil gas concentrations have only a limited use in the prediction of indoor 222Rn concentrations.

  11. 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.

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

    PubMed

    Jelle, Bjørn Petter

    2012-02-01

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

  14. Indoor radon problem in energy efficient multi-storey buildings.

    PubMed

    Yarmoshenko, I V; Vasilyev, A V; Onishchenko, A D; Kiselev, S M; Zhukovsky, M V

    2014-07-01

    Modern energy-efficient architectural solutions and building construction technologies such as monolithic concrete structures in combination with effective insulation reduce air permeability of building envelope. As a result, air exchange rate is significantly reduced and conditions for increased radon accumulation in indoor air are created. Based on radon survey in Ekaterinburg, Russia, remarkable increase in indoor radon concentration level in energy-efficient multi-storey buildings was found in comparison with similar buildings constructed before the-energy-saving era. To investigate the problem of indoor radon in energy-efficient multi-storey buildings, the measurements of radon concentration have been performed in seven modern buildings using radon monitoring method. Values of air exchange rate and other parameters of indoor climate in energy-efficient buildings have been estimated.

  15. 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.

  16. Indoor radon and lung cancer in China.

    PubMed

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

    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. However, further studies in other population groups are needed to clarify the carcinogenic potential of indoor radon.

  17. The Influence of Internal Wall and Floor Covering Materials and Ventilation Type on Indoor Radon and Thoron Levels in Hospitals of Kermanshah, Iran

    PubMed Central

    Pirsaheb, Meghdad; Najafi, Farid; Haghparast, Abbas; Hemati, Lida; Sharafi, Kiomars; Kurd, Nematullah

    2016-01-01

    Background Building materials and the ventilation rate of a building are two main factors influencing indoor radon and thoron levels (two radioactive gases which have the most important role in human natural radiation exposure within dwellings). Objectives This analytical descriptive study was intended to determine the relationship between indoor radon and thoron concentrations and the building materials used in interior surfaces, as well as between those concentrations and the type of ventilation system (natural or artificial). Materials and Methods 102 measurements of radon and thoron levels were taken from different parts of three hospital buildings in the city of Kermanshah in the west of Iran, using an RTM-1688-2 radon meter. Information on the type of building material and ventilation system in the measurement location was collected and then analyzed using Stata 8 software and multivariate linear regression. Results In terms of radon and thoron emissions, travertine and plaster were found to be the most appropriate and inappropriate covering for walls, respectively. Furthermore, granite and travertine were discovered to be inappropriate materials for flooring, while plastic floor covering was found suitable. Natural ventilation performed better for radon, while artificial ventilation worked better for thoron. Conclusions Internal building materials and ventilation type affect indoor radon and thoron concentrations. Therefore, the use of proper materials and adequate ventilation can reduce the potential human exposure to radon and thoron. This is of utmost importance, particularly in buildings with a high density of residents, including hospitals. PMID:28180013

  18. Control of indoor radon and radon progeny concentrations

    SciTech Connect

    Sextro, R.G.

    1985-05-01

    There are three general categories of techniques for the control of radon and radon progeny concentrations in indoor air - restriction of radon entry, reduction of indoor radon concentrations by ventilation or air cleaning, and removal of airborne radon progeny. The predominant radon entry process in most residences appears to be pressure driven flow of soil gas through cracks or other openings in the basement, slab, or subfloor. Sealing these openings or ventilation of the subslab or subfloor space are methods of reducing radon entry rates. Indoor radon concentrations may be reduced by increased ventilation. The use of charcoal filters for removal of radon gas in the indoor air by adsorption has also been proposed. Concentrations of radon progeny, which are responsible for most of the health risks associated with radon exposures, can be controlled by use of electrostatic or mechanical filtration. Air circulation can also reduce radon progeny concentrations in certain cases. This paper reviews the application and limitations of each of these control measures and discusses recent experimental results.

  19. 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

  20. 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.

  1. 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...

  2. Understanding the origin of radon indoors: Building a predictive capability

    SciTech Connect

    Sextro, R.G.

    1985-12-01

    Indoor radon concentrations one to two orders of magnitude higher than the US average of approx.60 Bq m/sup -3/ (approx.1.5 pCi L/sup -1/) are not uncommon, and concentrations greater than 4000 Bq m/sup -3/ have been observed in houses in areas with no known artificially-enhanced radon sources. In general, source categories for indoor radon are well known: soil, domestic water, building materials, outdoor air, and natural gas. Soil is thought to be a major source of indoor radon, either through molecular diffusion (usually a minor component) or convective flow of soil gas. While soil gas flow into residences has been demonstrated, no detailed understanding of the important factors affecting the source strength of radon from soil has yet emerged. Preliminary work in this area has identified a number of likely issues, including the concentration of radium in the soil, the emanating fraction, soil type, soil moisture content, and other factors that would influence soil permeability and soil gas transport. Because a significant number of dwellings are expected to have indoor radon concentrations above guideline levels, a predictive capability is needed that would help identify geographical areas having the potential for high indoor concentrations. This paper reviews the preliminary work that has been done to identify important soil and building characteristics that influence the migration of radon and outlines the areas of further research necessary for development of a predictive method. 32 refs., 4 figs.

  3. 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)

  4. 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.

  5. 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.

  6. 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%.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. Variation in residential radon levels in new Danish homes.

    PubMed

    Bräuner, E V; Rasmussen, T V; Gunnarsen, L

    2013-08-01

    Radon-222 gas arises from the radioactive decay of radium-226 and has a half-life of 3.8 days. This gas percolates up through soil into buildings, and if it is not evacuated, there can be much higher exposure levels indoors than outdoors, which is where human exposure occurs. Radon exposure is classified as a human carcinogen, and new Danish homes must be constructed to ensure indoor radon levels below 100 Bq/m(3). Our purpose was to assess how well 200 newly constructed single detached homes perform according to building regulations pertaining to radon and identify the association between indoor radon in these homes and municipality, home age, floor area, floor level, basement, and outer wall and roof construction. Median (5-95 percentile) indoor radon levels were 36.8 (9.0-118) Bq/m(3) , but indoor radon exceeded 100 Bq/m(3) in 14 of these new homes. The investigated variables explained nine percent of the variation in indoor radon levels, and although associations were positive, none of these were statistically significant. In this study, radon levels were generally low, but we found that 14 (7%) of the 200 new homes had indoor radon levels over 100 Bq/m(3). More work is needed to determine the determinants of indoor radon.

  13. Some remarks on the indoor radon distribution in a country.

    PubMed

    Hámori, K; Tóth, E; Losonci, A; Minda, M

    2006-08-01

    From the point of view of indoor radon activity concentrations, a country is characterized correctly by two parameters (GM and GSD) of a lognormal distribution if and only if hypothesis tests do not reject the distribution of the local radon activity concentrations as a lognormal one. The authors introduce a way to obtain an empirical distribution using a stratum system covering almost the whole country and in each stratum the lognormal model is acceptable according to hypothesis tests. The sample for the analysis is provided by the measurement of radon level in 15,619 Hungarian homes.

  14. 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.

  15. 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

  16. Radon

    MedlinePlus

    ... Action Plan: A Strategy for Saving Lives . Indoor Air Quality Home Page Frequent Questions about Radon Find Local ... Radon can have a big impact on indoor air quality . Individuals and Families Health Risk of Radon Citizen's ...

  17. Factors affecting indoor radon concentrations in the United Kingdom.

    PubMed

    Gunby, J A; Darby, S C; Miles, J C; Green, B M; Cox, D R

    1993-01-01

    Data collected in a nationwide study on natural radiation exposure in UK dwellings (Wrixon et al. 1988) were re-analyzed to investigate the effects of rock type and various building and lifestyle characteristics, taken into account simultaneously, on indoor radon concentrations. A multiplicative model which takes into consideration the outdoor radon concentration is used. Indoor radon concentrations were found to be influenced by type of rock underlying the dwelling, double glazing, house type, floor level of rooms in which measurements were taken, window opening habits in the main bedroom, building materials used in the construction of the walls, floor type, and draught proofing. However, these eight factors together account for only 22% of the variation between dwellings. Estimates of the size of the effect associated with each factor are given.

  18. The Italian national survey of indoor radon exposure.

    PubMed

    Sciocchetti, G; Scacco, F; Baldassini, P G; Battella, C; Bovi, M; Monte, L

    1985-10-01

    An investigation is being developed by the Comitato Nazionale per la Ricerca e per lo Sviluppo dell'Energia Nucleare e delle Energie Alternative, ENEA, to assess the indoor exposure of the Italian population. The programme, which started in 1982, includes regional and local surveys in all the administrative districts and intensive investigations of factors which influence indoor radon levels. The survey is organized by statistical areas of sampling to obtain representative samples of houses. The definition of the areas takes into account basic parameters e.g. geolithological environments, radon soil gas from underlying soils and rocks, specific activities of local building materials, climatic and seasonal variations, building technology, types of houses and town planning. The collected data may also be used for the compilation of radon risk maps to plan special monitoring and remedial actions if needed. Preliminary results concerning the above items are discussed.

  19. The Spanish indoor radon mapping strategy.

    PubMed

    Sainz-Fernandez, C; Fernandez-Villar, A; Fuente-Merino, I; Gutierrez-Villanueva, J L; Martin-Matarranz, J L; Garcia-Talavera, M; Casal-Ordas, S; Quindós-Poncela, L S

    2014-11-01

    Indoor radon mapping still represents a valuable tool for drawing the picture of the exposure of general public due to radon and radon progeny inhalation in a residential context. The information provided by means of a map is useful not only as awareness and strategic element for authorities and policy-makers, but also as a scientific start-up point in the design of epidemiological and other specific studies on exposure to natural radiation. The requirements for a good mapping are related to harmonisation criteria coming from European recommendations, as well as to national/local characteristics and necessities. Around 12,000 indoor radon measurements have been made since the Spanish national radon programme began at the end of the 1980s. A significant proportion of them resulted from the last campaign performed from 2009 to 12. This campaign completed the first version of a map based on a grid 10 × 10 km(2). In this paper, the authors present the main results of a new map together with the criteria adopted to improve the number of measurements and the statistical significance of them.

  20. 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.

  1. A model for indoor radon variations

    SciTech Connect

    Arvela, H.; Winqvist, K. )

    1989-01-01

    The model relates radon concentration to variations in source strength, air exchange rate, and meteorological factors. The diffusion source represents radon diffused from building materials or from soil. The pressure-difference driven flow represents radon flowing with soil pore air and driven by the stack effect. In a house with diffusion source, the radon concentration decreases when the air exchange rate increases due to increasing temperature differences, whereas the flow source causes an increasing concentration. This is due to the fact that the effect of the source strength increase is stronger than the decreasing effect of air exchange of concentration. The winter-summer concentration ratio depends on the combination of the two types of source. A pure pressure-difference driven flow gives a winter-summer ratio of 2-3 (winter -5{degree}C, summer +15{degree}C, wind speed 3 m/s). A strong contribution of a diffusion source is needed to cause a summer concentration higher than the winter concentration. The model is in agreement with the winter-summer concentration ratios measured. This ratio increases with the increasing winter concentration. The results indicate that radon concentration must be taken into account in analyses of seasonal variations of indoor radon. In houses with a diffusion source, the diurnal maximum occurs in the afternoon; in houses with a pressure-difference driven flow, the maximum is reached in the early morning.

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

    PubMed

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

    2017-01-01

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

  3. 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

  4. 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.

  5. Seasonal indoor radon concentration in Eskisehir, Turkey.

    PubMed

    Sogukpinar, H; Algin, E; Asici, C; Altinsoz, M; Cetinkaya, H

    2014-12-01

    Indoor radon concentrations are subject to seasonal variation, which directly depends on weather conditions. The seasonal indoor radon concentrations were measured and the annual effective dose was estimated for the city centre of Eskisehir, Turkey. In order to reflect annual averages measurements were performed over all seasons (winter, spring, summer and autumn) including also the entire year. Measurements were carried out using Kodak-Pathe LR 115 Type II passive alpha track detectors in 220 different houses. A total of 534 measurements including measurements of different seasons were taken between 2010 and 2011. The radon concentrations for winter ranged from 34 to 531 Bq m(-3), for spring ranged from 22 to 424 Bq m(-3), for summer ranged from 25 to 320 Bq m(-3), and for autumn ranged from 19 to 412 Bq m(-3). Yearly measurements ranged from 19 to 338 Bq m(-3). In this study the average annual effective total dose from radon and its decay products was calculated to be 3.398 mSv y(-1).

  6. 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.

  7. 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.

  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. Effect of energy-efficient measures in building construction on indoor radon in Russia.

    PubMed

    Vasilyev, A; Yarmoshenko, I

    2016-06-29

    The effect of implementation of energy-efficient measures in building construction was studied. Analysis includes study of indoor radon in energy-efficient buildings in Ekaterinburg, Russia, and results of radiation measurements in 83 regions of Russia conducted within the regional programmes. The forecast distribution of radon concentration in Ekaterinburg was built with regard to the city development programme. With Ekaterinburg taken as representative case, forecast distribution of radon concentration in Russia in 2030 was built. In comparison with 2000, average radon concentration increases by a factor of 1.42 in 2030 year; percentage above the reference level 300 Bq/m(3) increases by a factor of 4 in 2030 year. It is necessary to perceive such an increase with all seriousness and to prepare appropriate measures for optimization of protection against indoor radon. Despite the high uncertainty, reconstructed distribution of radon concentration can be applied for justification of measures to be incorporated in the radon mitigation strategy.

  10. Indoor and soil gas radon simultaneous measurements for the purpose of detail analysis of radon entry pathways into houses.

    PubMed

    Froňka, A

    2011-05-01

    Detailed knowledge of radon transport mechanisms from the subsoil into the indoor environment is essential for the correct interpretation of results of short-term indoor radon measurements and for proper and effective design of radon mitigation systems. Radon transfer factor time variations have been studied based on simultaneous continuous indoor and soil gas radon measurements within the framework of complex radon diagnosis of individual buildings. In this context, the key influencing factors have been identified and analysed in order to provide satisfactory explanation on radon entry variations under different measurement conditions. Moreover, a new significant manner of radon entry into the indoor environment has been identified and will be discussed in detail.

  11. 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.

  12. MEASUREMENT OF INDOOR RADON-THORON IN AIR AND EXHALATION FROM SOIL IN THE ENVIRONMENT OF WESTERN HARYANA, INDIA.

    PubMed

    Mann, Nisha; Kumar, Amit; Kumar, Sushil; Chauhan, R P

    2016-10-01

    Measurement of indoor radon and thoron is important because the inhalation of radon-thoron and their daughters contributes more than 50 % of the total dose from natural sources. One of the important parameters to find out the contribution of soil and building materials towards indoor radon is radon exhalation rates, which can be used for estimation of indoor radon levels. The indoor radon and thoron levels from the air and radon exhalation rates from soil samples collected from two districts (Hisar and Fatehabad) of Western Haryana are measured using pin-hole-based radon-thoron dosimeter and LR-115 solid-state nuclear track detector by canister technique. The results show that the indoor radon and thoron levels from Hisar district varied from 11 to 112 and 11 to 80 Bq m(-3), while for Fatehabad district from 5 to 24 and 59 to 105 Bq m(-3), respectively, in summer season. In winter season, indoor radon and thoron levels from Hisar district varied from 15 to 43 and 32 to 102 Bq m(-3), while for Fatehabad district from 18 to 31 and 11 to 80 Bq m(-3), respectively. The indoor radon levels of 95 % locations lie well below the limit recommended by International Commission of Radiation Protection, 2011. The radon mass exhalation rate varied from 6 to 56 mBq kg(-1) h(-1) The radon mass exhalation rates from the soil samples were lower than the worldwide average, i.e. 56 mBq kg(-1) h(-1) There exists a poor correlation between indoor radon and exhalation rates. More investigations of measurement of radionuclide contents from rock and stone of study area can improve the understanding.

  13. 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).

  14. 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.

  15. Factors affecting yearly variations of indoor radon concentrations

    SciTech Connect

    Steck, D.J.; Baynes, S.A.

    1996-06-01

    Since indoor radon exposures take place over many years while radon measurement periods are shorter, we are studying the yearly variation of indoor radon concentrations in approximately 100 houses located throughout Minnesota. Most houses were initially measured for one or more years in the late 1980`s and for 5 consecutive years starting in 1990. Two houses have been monitored for 12 y. Each year, two alpha track detectors were placed on the two lowest livable levels. The year-to-year variations averaged about 35% (corrected for instrumental uncertainties) in both basements and first floors. The minimum observed variation was 5% and the maximum was 130%. Some homes have shown substantial variation associated with Structural modifications. While most homes show no obvious systematic trends, a few houses have shown temporal trends that may be associated with aging or climate. We are studying possible correlation between year-to-year radon variation, climatic variables (yearly-average and seasonal such as heating/cooling degree days, precipitation, soil moisture), and structural changes.

  16. 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...

  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. 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.

  19. Indoor radon measurements in the dwellings of Punjab and Himachal Pradesh, India.

    PubMed

    Rani, Asha; Singh, Surinder; Duggal, Vikas

    2013-01-01

    The measurement of indoor radon concentrations were performed in the dwellings of the Punjab and Himachal Pradesh, India by using LR-115 type II Solid-State Nuclear Track Detectors in the bare mode. The annual average indoor radon concentrations in the dwellings are found to vary from 114 to 400 Bq m(-3) with an average of 194 Bq m(-3). In ∼22 % of the dwellings the indoor radon activity concentration values lies in the range of action level (200-300 Bq m(-3)) and in ∼11 % of the dwellings above the upper limit of action level recommended by the International Commission on Radiological Protection (ICRP). The annual effective dose (AED) varies from 2.88 to 10.08 mSv with an average of 4.88 mSv. In most of the villages, the AED lies in the range of action level (3-10 mSv) recommended by the ICRP. The seasonal variation in indoor radon reveals the maximum values in winter and minimum in summer. The winter/summer ratio of indoor radon ranges from 1.15 to 1.62 with an average of 1.31. Analysis of ventilation conditions reveal that the indoor radon concentration values are more in poorly ventilated dwellings compared with the well-ventilated ones.

  20. 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.

  1. 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.

  2. Indoor residential radon exposure and risk of childhood acute myeloid leukaemia

    PubMed Central

    Steinbuch, M; Weinberg, C R; Buckley, J D; Robison, L L; Sandler, D P

    1999-01-01

    Exposure to radon has been identified as a risk factor for lung cancer in uranium miners, but evidence of adverse health effects due to indoor radon exposure is inconsistent. Ecological studies have suggested a correlation between indoor radon levels and leukaemia incidence. We evaluated the risk associated with indoor residential radon exposure within a larger interview-based case–control study of risk factors for childhood acute myeloid leukaemia (AML). A total of 173 cases and 254 controls met the eligibility criteria, and information was collected through telephone interviews with parents and analysis of alpha-track radon detectors placed in the home for a period of 1 year. No association was observed between radon exposure and risk of AML, with adjusted odds ratios of 1.2 (95% confidence interval (CI) 0.7–1.8) for 37–100 Bq m–3 and 1.1 (95% CI 0.6–2.0) for > 100 Bq m–3 compared with < 37 Bq m–3. Although there was an inverse association between radon level and AML risk among children < 2 years at diagnosis, among children ≥2 years, AML risk was increased among those with higher radon exposure. The observed association after age 2 is most likely due to chance. Overall, there was no association between residential radon and risk of childhood AML. © 1999 Cancer Research Campaign PMID:10555766

  3. The correlation between indoor and in soil radon concentrations in a desert climate

    NASA Astrophysics Data System (ADS)

    Al-Khateeb, H. M.; Aljarrah, K. M.; Alzoubi, F. Y.; Alqadi, M. K.; Ahmad, A. A.

    2017-01-01

    This study examines the levels and the correlation between indoor and in soil radon concentration in a desert climate. The measurements are carried out, in Jordan desert in AlMafraq district, using the passive integrated technique. An intelligent automated tracks counting system, modified recently by our group, is used to estimate the overlapping tracks and to decrease the counting percentage error. Results show that radon concentration in soil expands from 4.09 to 11.30 kBq m-3, with an average of 7.53 kBq m-3. Indoor radon concentrations vary from 20.2 Bq m-3 in the AlMafraq city to 46.7 Bq m-3 in Housha village and with an average of 29.6 Bq m-3. All of individual indoor radon concentrations are lower than the limit (100 Bq m-3) recommended by WHO except two dwellings in Housha village which found being higher than this limit. A moderate linear correlation (R2=0.66) was observed between indoor and in soil radon concentrations in the investigated region. Our results showed that an in soil radon measurement can be a satisfactory predictor for indoor radon potential.

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

    PubMed

    Musavi Nasab, S M; Negarestani, A

    2013-01-01

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

  5. Seasonal and spatial variations in Rn-222 and Rn-220 in soil gas, and implications for indoor radon levels.

    PubMed

    Sharman, G

    1992-12-01

    Rn-222 enters dwellings as a component of soil gas drawn from the soil by mass flow driven by the pressure difference between the house and soil beneath. In a site on Northampton Sand Ironstone (Aalenian), a preferred path of emanation (hotspot) was found. A difference of 63 Bq L(-1) Rn-222 was recorded in July between this point and another 3 m away. Rn-222 in this hotspot shows 12% less variation annually than the surrounding rock. During winter, Rn-222 values within 1.6 m of the house were 44% lower than those at more than 4 m away. Rn-222 showed a 99.5% negative correlation with wind run, showing that on this soil wind pressure can significantly reduce radon in the soil at 500 mm depth. Rn-220 in soil gas correlated positively at the 99.5% level with grass and air temperatures. Rn-220 was not associated with the hotspot.

  6. 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.

  7. A nation-wide survey on indoor radon from 2007 to 2010 in Japan.

    PubMed

    Suzuki, Gen; Yamaguchi, Ichiro; Ogata, Hiromitsu; Sugiyama, Hideo; Yonehara, Hidenori; Kasagi, Fumiyoshi; Fujiwara, Saeko; Tatsukawa, Yoshimi; Mori, Ippei; Kimura, Shinzo

    2010-01-01

    In two previous nation-wide surveys in the late 1980s and early 1990s, Japanese indoor radon concentrations increased in homes built after the mid 1970s. In order to ascertain whether this trend continued, a nation-wide survey was conducted from 2007 to 2010. In total 3,900 houses were allocated to 47 prefectures by the Neyman allocation method and 3,461 radon measurements were performed (88.7% success). The fraction of reinforced concrete / concrete block buildings was 32.4%, similar to the value from national statistics. Arithmetic mean (standard deviation, SD) and geometric mean (geometric SD) of radon concentration after adjusting for seasonal fluctuation were 14.3 (14.7) and 10.8 (2.1) Bq/m(3). The corresponding population-weighted values were 13.7 (12.3) and 10.4 (2.0) Bq/m(3), respectively. It was estimated that only 0.1% of dwellings exceed 100 Bq/m(3), a new WHO reference level for indoor radon. Radon concentrations were highest in houses constructed in the mid 1980s and decreased thereafter. In conclusion, arithmetic mean indoor radon in the present survey was slightly lower than in previous surveys and significant reductions in indoor radon concentrations in both wooden and concrete houses can be attributed to alterations in Japanese housing styles in recent decades.

  8. 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.

  9. Large-scale radon hazard evaluation in the Oslofjord region of Norway utilizing indoor radon concentrations, airborne gamma ray spectrometry and geological mapping.

    PubMed

    Smethurst, Mark Andrew; Strand, Terje; Sundal, Aud Venke; Rudjord, Anne Liv

    2008-12-15

    We test whether airborne gamma ray spectrometer measurements can be used to estimate levels of radon hazard in the Oslofjord region of Norway. We compile 43,000 line kilometres of gamma ray spectrometer data from 8 airborne surveys covering 10,000 km2 and compare them with 6326 indoor radon measurements. We find a clear spatial correlation between areas with elevated concentrations of uranium daughters in the near surface of the ground and regions with high incidence of elevated radon concentrations in dwellings. This correlation permits cautious use of the airborne data in radon hazard evaluation where direct measurements of indoor radon concentrations are few or absent. In radon hazard evaluation there is a natural synergy between the mapping of radon in indoor air, bedrock and drift geology mapping and airborne gamma ray surveying. We produce radon hazard forecast maps for the Oslofjord region based on a spatial union of hazard indicators from all four of these data sources. Indication of elevated radon hazard in any one of the data sets leads to the classification of a region as having an elevated radon hazard potential. This approach is inclusive in nature and we find that the majority of actual radon hazards lie in the assumed elevated risk regions.

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

    PubMed Central

    Foster, Stephanie; Everett Jones, Sherry

    2016-01-01

    Radon is a naturally occurring, colorless, odorless, and tasteless radioactive gas. Without testing, its presence is unknown. Using nationally representative data from the 2012 School Health Policies and Practices Study, we examined whether the prevalence of school district policies for radon testing and for radon-resistant new construction practices varied by district location in relation to the U.S. Environmental Protection Agency Map of Radon Zones. Among school districts located in counties with high predicted average indoor radon, 42.4% had policies for radon testing and 37.5% had policies for radon-resistant new construction practices. These findings suggest a critical need for improved awareness among policy makers regarding potential radon exposure for both students and school staff. PMID:27983613

  11. A study on the correlation between soil radon potential and average indoor radon potential in Canadian cities.

    PubMed

    Chen, Jing; Ford, Ken L

    2017-01-01

    Exposure to indoor radon is identified as the main source of natural radiation exposure to the population. Since radon in homes originates mainly from soil gas radon, it is of public interest to study the correlation between radon in soil and radon indoors in different geographic locations. From 2007 to 2010, a total of 1070 sites were surveyed for soil gas radon and soil permeability. Among the sites surveyed, 430 sites were in 14 cities where indoor radon information is available from residential radon and thoron surveys conducted in recent years. It is observed that indoor radon potential (percentage of homes above 200 Bq m(-3); range from 1.5% to 42%) correlates reasonably well with soil radon potential (SRP: an index proportional to soil gas radon concentration and soil permeability; average SRP ranged from 8 to 26). In five cities where in-situ soil permeability was measured at more than 20 sites, a strong correlation (R(2) = 0.68 for linear regression and R(2) = 0.81 for non-linear regression) was observed between indoor radon potential and soil radon potential. This summary report shows that soil gas radon measurement is a practical and useful predictor of indoor radon potential in a geographic area, and may be useful for making decisions around prioritizing activities to manage population exposure and future land-use planning.

  12. 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.

  13. Bagged neural network model for prediction of the mean indoor radon concentration in the municipalities in Czech Republic.

    PubMed

    Timkova, Jana; Fojtikova, Ivana; Pacherova, Petra

    2017-01-01

    The purpose of the study is to determine radon-prone areas in the Czech Republic based on the measurements of indoor radon concentration and independent predictors (rock type and permeability of the bedrock, gamma dose rate, GPS coordinates and the average age of family houses). The relationship between the mean observed indoor radon concentrations in monitored areas (∼22% municipalities) and the independent predictors was modelled using a bagged neural network. Levels of mean indoor radon concentration in the unmonitored areas were predicted using the bagged neural network model fitted for the monitored areas. The propensity to increased indoor radon was determined by estimated probability of exceeding the action level of 300Bq/m(3).

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

    PubMed Central

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

    2014-01-01

    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. PMID:25063783

  15. A theoretical investigation of the distribution of indoor radon concentrations

    NASA Astrophysics Data System (ADS)

    Rabi, R.; Oufni, L.

    2016-11-01

    Inhalation of radon (222Rn) and its decay products are a major source of natural radiation exposure. It is known from recent surveys in many countries that radon and its progeny contribute significantly to total inhalation dose and it is fairly established that radon when inhaled in large quantity causes lung disorder. In recent times, numerical modelling 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 the Finite Volume Method (FVM) for studying the radon distribution indoor. The findings show that the radon concentration which is distributed in a non-homogeneous way in the room is due to the difference in the radon concentration of different sources (wall, floor and ceiling). Moreover, the radon concentration is much larger near walls, and decreases in the middle of the room because of the effect of air velocity. We notice that the simulation results of radon concentration are in agreement with the results of other experimental studies. The annual effective dose of radon in the model room has been also investigated.

  16. 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.

  17. 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.

  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. 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.

  20. Indoor radon and thoron concentrations in some towns of central and South Serbia.

    PubMed

    Vuckovic, Biljana; Gulan, Ljiljana; Milenkovic, Biljana; Stajic, Jelena M; Milic, Gordana

    2016-12-01

    This study presents the results of indoor radon and thoron activity concentrations of some municipalities in central and south part of Serbia: Krusevac, Brus, Blace and Kursumlija. Measurements were carried out in 60 dwellings during the winter season. Passive discriminative radon-thoron detectors known as UFO detectors were used. The mean values of indoor radon and thoron concentrations were 82 Bq m(-3) and 42 Bq m(-3), respectively. Population-weighted mean values were 76 Bq m(-3) and 40 Bq m(-3), respectively. 26.7% of dwellings had radon concentration higher than 100 Bq m(-3) (one location had even more than 300 Bq m(-3)). There are no statistically significant correlations of indoor radon and thoron concentrations neither with the period of house construction, nor with the existence of a basement. The results of this study represent the first step of investigating radon and thoron levels in these parts of Serbia and therefore could be the basis for creating a radon map.

  1. 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.

  2. 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.

  3. Update of Ireland's national average indoor radon concentration - Application of a new survey protocol.

    PubMed

    Dowdall, A; Murphy, P; Pollard, D; Fenton, D

    2017-04-01

    In 2002, a National Radon Survey (NRS) in Ireland established that the geographically weighted national average indoor radon concentration was 89 Bq m(-3). Since then a number of developments have taken place which are likely to have impacted on the national average radon level. Key among these was the introduction of amending Building Regulations in 1998 requiring radon preventive measures in new buildings in High Radon Areas (HRAs). In 2014, the Irish Government adopted the National Radon Control Strategy (NRCS) for Ireland. A knowledge gap identified in the NRCS was to update the national average for Ireland given the developments since 2002. The updated national average would also be used as a baseline metric to assess the effectiveness of the NRCS over time. A new national survey protocol was required that would measure radon in a sample of homes representative of radon risk and geographical location. The design of the survey protocol took into account that it is not feasible to repeat the 11,319 measurements carried out for the 2002 NRS due to time and resource constraints. However, the existence of that comprehensive survey allowed for a new protocol to be developed, involving measurements carried out in unbiased randomly selected volunteer homes. This paper sets out the development and application of that survey protocol. The results of the 2015 survey showed that the current national average indoor radon concentration for homes in Ireland is 77 Bq m(-3), a decrease from the 89 Bq m(-3) reported in the 2002 NRS. Analysis of the results by build date demonstrate that the introduction of the amending Building Regulations in 1998 have led to a reduction in the average indoor radon level in Ireland.

  4. 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.

  5. Indoor Radon Radioactivity at the University of Brunei Darussalam

    NASA Astrophysics Data System (ADS)

    Sheng, T. K.; Jer, H. S.

    - Indoor radon radioactivity in the rooms on the ground floor and first floor of the Physics Department, Faculty of Science, Universiti Brunei Darussalam was measured using a system that consists of an air filter pump, ZnS detector, photomultiplier tube and counter. Ground floor rooms' radon radioactivity was found to be about three times higher than that of the first floor. The maximum ground floor indoor radioactivity is only 0.39 Bqm-3, a value relatively low and safe compared to the mean outdoor radon concentration of 1.41 Bqm-3 measured (HU and TAN, 2000). The main source of radon emanation originates from the ground soil rather than the building materials.

  6. Variation of Indoor Radon Levels in Some Caves of Parque Estadual Turistico do Alto Ribeira (PETAR), SP, Brazil with Ventilation and Rain

    SciTech Connect

    Alberigi, Simone; Pecequilo, Brigitte Roxana Soreanu

    2008-08-07

    In order to assess the radon exposure for the tour guide workers, radon levels in several galleries of the most visited caves of PETAR (High Ribeira River Turistic State Park), were determined by using Makrofol E tracks detectors. A two-years surveillance, from 2003 to 2005, showed radon average levels varying from 153{+-}44 Bq{center_dot}m{sup -3} to 6358{+-}1619 Bq{center_dot}m{sup -3}. Those results showed that the wide variation between the minimum and maximum concentrations values are strongly related with cave ventilation. In order to establish other factors contributing to this variation, beside the well known temperature effect, rain data over the entire period were also considered, showing that, apparently, radon concentrations inside the caves rise with drought.

  7. Variation of Indoor Radon Levels in Some Caves of Parque Estadual Turístico do Alto Ribeira (PETAR), SP, Brazil with Ventilation and Rain

    NASA Astrophysics Data System (ADS)

    Alberigi, Simone; Pecequilo, Brigitte Roxana Soreanu

    2008-08-01

    In order to assess the radon exposure for the tour guide workers, radon levels in several galleries of the most visited caves of PETAR (High Ribeira River Turistic State Park), were determined by using Makrofol E tracks detectors. A two-years surveillance, from 2003 to 2005, showed radon average levels varying from 153±44 Bqṡm-3 to 6358±1619 Bqṡm-3. Those results showed that the wide variation between the minimum and maximum concentrations values are strongly related with cave ventilation. In order to establish other factors contributing to this variation, beside the well known temperature effect, rain data over the entire period were also considered, showing that, apparently, radon concentrations inside the caves rise with drought.

  8. Relationships between indoor radon concentrations, thermal retrofit and dwelling characteristics.

    PubMed

    Collignan, Bernard; Le Ponner, Eline; Mandin, Corinne

    2016-12-01

    A monitoring campaign was conducted on a sample of more than 3400 dwellings in Brittany, France from 2011 to 2014. The measurements were collected using one passive dosimeter per dwelling over two months during the heating season, according to the NF ISO 11665-8 (2013) standard. Moreover, building characteristics such as the period of construction, construction material, type of foundation, and thermal retrofit were determined using a questionnaire. The final data set consisted of 3233 houses with the measurement results and the questionnaire answers. Multivariate linear regression models were applied to explore the relationships between the indoor radon concentrations and building characteristics, particularly the thermal retrofit. The geometric mean of the indoor radon concentration was 155 Bq m(-3) (with a geometric standard deviation of 3). The houses that had undergone a thermal retrofit had a higher average radon concentration than those that had not, which may have been due to a decrease in air permeability of the building envelope following rehabilitation work that did not systematically include proper management of the ventilation. Other building characteristics, primarily the building material and the foundation type, were associated with the indoor radon concentration. The indoor radon concentrations were higher in older houses built with granite or other stone, with a slab-on-grade foundation and without any ventilation system.

  9. 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.

  10. 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.

  11. 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.

  12. Estimation of annual effective dose from indoor radon/thoron concentrations and measurement of radon concentrations in soil.

    PubMed

    Mehra, Rohit; Bala, Pankaj

    2014-01-01

    Radon short-lived decay products generated from the earth is one of the serious indoor air and soil pollutants. The RAD-7 Electronic Radon Detector with a special accessory is used for the purpose of measurement. The radon and thoron concentrations in the houses of the study area are found to vary from 35±0.5 to 315.2±5.35 Bq m(-3) and 66.1±2.3 to 1710±139.36 Bq m(-3) with the average values of 98.65±1.9 and 388.19±11 Bq m(-3), respectively. From indoor air, the total annual effective dose is calculated and it varies from 0.88 to 7.94 mSv y(-1). The preliminary investigation shows that the thoron concentration is higher than the radon concentration in the houses of the study area. In general, the values of the indoor air are within the recommended action level of the International Commission on Radiological Protection, 2009.

  13. 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.

  14. Measurement of indoor and outdoor radon concentrations during Superstorm Sandy.

    PubMed

    Kotrappa, Payasada; Paul, Prateek; Stieff, Alex; Stieff, Frederick

    2013-12-01

    Superstorm Sandy affected much of the US East Coast extending over 1800 km. It passed over the test location in the State of Maryland on 29 October 2012. Being 350 km away from the regions of highest intensity the storm was of lower intensity at the test location. Continuous radon monitors and passive radon monitors were used for the measurement. The test location was the basement of a single family home representing the indoor concentration. A partially opened garage of the same test home represented the outdoor radon concentration. In 24 h, the atmospheric pressure dropped from 990 to 960 mbar and the indoor radon concentration increased from 70 to 1500 Bq m(-3) and returned to the normal of 70 Bq m(-3) at the end of the storm. Throughout the storm, the outdoor radon concentration was not significantly affected. Probable reasons for such surprisingly large changes are discussed. However, the outdoor temperature dropped from 13°C to 7°C during the radon peak.

  15. 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; ...

  16. 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.

  17. 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)

  18. 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).

  19. 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.

  20. 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.

  1. 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.

  2. 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 ...

  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. 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.

  5. 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.

  6. 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.

  7. State Indoor Radon Grant (SIRG) Program

    EPA Pesticide Factsheets

    Each year EPA distributes grant funds to the States and Tribes to support their radon risk reduction programs. The State and Tribal programs are critical to the Agency's national risk reduction effort and its achievements. These SIRG funds are put to a wid

  8. 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).

  9. 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.

  10. Lung cancer deaths from indoor radon and the cost effectiveness and potential of policies to reduce them

    PubMed Central

    Read, Simon; McGale, Paul; Darby, Sarah

    2009-01-01

    Objective To determine the number of deaths from lung cancer related to radon in the home and to explore the cost effectiveness of alternative policies to control indoor radon and their potential to reduce lung cancer mortality. Design Cost effectiveness analysis. Setting United Kingdom. Data sources Epidemiological data on risks from indoor radon and from smoking, vital statistics on deaths from lung cancer, survey information on effectiveness and costs of radon prevention and remediation. Main outcome measures Estimated number of deaths from lung cancer related to indoor radon, lifetime risks of death from lung cancer before and after various potential interventions to control radon, the cost per quality adjusted life year (QALY) gained from different policies for control of radon, and the potential of those policies to reduce lung cancer mortality. Results The mean radon concentration in UK homes is 21 becquerels per cubic metre (Bq/m3). Each year around 1100 deaths from lung cancer (3.3% of all deaths from lung cancer) are related to radon in the home. Over 85% of these arise from radon concentrations below 100 Bq/m3 and most are caused jointly by radon and active smoking. Current policy requiring basic measures to prevent radon in new homes in selected areas is highly cost effective, and such measures would remain cost effective if extended to the entire UK, with a cost per QALY gained of £11 400 ( €12 200; $16 913). Current policy identifying and remediating existing homes with high radon levels is, however, neither cost effective (cost per QALY gained £36 800) nor effective in reducing lung cancer mortality. Conclusions Policies requiring basic preventive measures against radon in all new homes throughout the UK would be cost effective and could complement existing policies to reduce smoking. Policies involving remedial work on existing homes with high radon levels cannot prevent most radon related deaths, as these are caused by moderate exposure

  11. 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.

  12. 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.

  13. 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.

  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. 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.

  16. Influence of surficial soil and bedrock on indoor radon in New York State homes. Task 2, Subtask 2 of an investigation of infiltration and indoor air quality in New York State homes

    SciTech Connect

    Kunz, C.

    1989-10-01

    Radon can enter a building from soil and bedrock through cracks or openings in the basement. Extrapolation from data obtained from studies of miners exposed to high concentrations of radon and other carcinogens over long periods indicates that radon gas in the home poses an increased risk of lung cancer. The project was initiated to determine the characteristics of soil and bedrock that contribute to the availability of radon for infiltration into the home, and the feasibility of using soil characteristics in mapping areas at higher risk for above-average indoor radon in New York State. After conducting soil surveys across the State, the researchers choose four areas for further study. Fifteen homes in each area were tested for indoor air concentrations of radon, air infiltration into the home, radon concentrations in the soil, and the permeability of the soil for gas flow. The researchers concluded that these parameters could be combined to obtain a Radon Index Number to predict mean indoor radon levels for a given area with similar soil geology. However, this measure has a limited ability to predict indoor radon levels for a particular home due to variations in construction as well as differences in soil and bedrock.

  17. 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%.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. The concept of equivalent radon concentration for practical consideration of indoor exposure to thoron.

    PubMed

    Chen, Jing; Moir, Deborah

    2012-01-01

    To consider the total exposure to indoor radon and thoron, a concept of equivalent radon concentration for thoron is introduced, defined as the radon concentration that delivers the same annual effective dose as that resulting from the thoron concentration. The total indoor exposure to radon and thoron is then the sum of the radon concentration and the equivalent radon concentration for thoron. The total exposure should be compared to the radon guideline value, and if it exceeds the guideline value, appropriate remedial action is required. With this concept, a separate guideline for indoor thoron exposure is not necessary. For homes already tested for radon with radon detectors, Health Canada's recommendation of a 3-month radon test performed during the fall/winter heating season not only ensures a conservative estimate of the annual average radon concentration but also covers well any potentially missing contribution from thoron exposure. In addition, because the thoron concentration is much lower than the radon concentration in most homes in Canada, there is no real need to re-test homes for thoron.

  3. 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.

  4. 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.

  5. Radon Levels in Nurseries and Primary Schools in Bragança District-Preliminary Assessment.

    PubMed

    Sousa, S I V; Branco, P T B S; Nunes, R A O; Alvim-Ferraz, M C M; Martins, F G

    2015-01-01

    Lung cancer has been associated with radon concentration even at low levels such as those found in dwellings. This study aimed to (i) determine radon diurnal variations in three nurseries and one primary school in the Bragança district (north of Portugal) and (ii) compare radon concentrations with legislated standards and assess the legislated procedures. Radon was measured in three nurseries and a primary school in a rural area with nongranite soil. Measurements were performed continuously to examine differences between occupation and nonoccupation periods. Indoor temperature and relative humidity were also measured continuously. A great variability was found in radon concentrations between the microenvironments examined. Radon concentrations surpassed by severalfold the recommended guidelines and thresholds, and excessive levels of health concern were sporadically found (361.5-753.5 Bq m(-3)). Thus, it is of importance to perform a national campaign on radon measurements and to reduce exposure.

  6. Radon levels inside residences in Mexico City

    SciTech Connect

    Espinoza, G. . Inst. de Fisica); Gammage, R.B. )

    1989-01-01

    Levels of radon were measured during winter and spring seasons inside 55 colonial and modern houses and 30 multifamily apartment buildings representative of middle and upper income families. The modern houses and apartment buildings in the southern section of the city had average radon levels exceeding 150 Bq m{sup {minus}3} with a maximum single measurement of 458 Bq m{sup {minus}3}. The colonial houses in the central downtown section had radon levels nearly all averaging below 100 Bq m{sup {minus}3}. Between the ground and third floor of the apartment buildings, radon levels diminished by tenfold indicating that entry of radon-bearing soil gas was largely responsible for the elevated concentrations of radon. The radon levels in winter exceeded by about 30% the radon levels during spring. The potentially adverse health effects of these radon levels may be exacerbated by the quality of air in Mexico City which during winter is often highly polluted. 7 refs., 2 figs.

  7. 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.

  8. 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...

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

    SciTech Connect

    Harley, N.H.

    1992-01-01

    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. The dosimetry has been extended to include organs other than the lung.

  10. 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)

  11. 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.

  12. 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.

  13. 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.

  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. 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.

  16. 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.

  17. Variation of soil radon concentrations in southern Ontario.

    PubMed

    Chen, J; Ly, J; Bergman, L; Wierdsma, J; Klassen, R A

    2008-01-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. Information on indoor radon concentrations is required to assess the lung cancer burden due to radon exposure. However, radon data in highly populated southern Ontario are very limited. Since radon in soil is believed to be the main source of radon in homes, measurements of soil gas radon concentrations can be used to estimate variations in radon potential of indoor environments. This study reports a transect survey of natural background variation in soil radon levels across southern Ontario. The results indicate that radon risk could be high in some areas of southern Ontario.

  18. 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.

  19. 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.

  20. 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 ...

  1. 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.

  2. Application of polystyrene films for indoor radon dosimetry as SSNTD.

    PubMed

    Hadad, Kamal; Sarshough, Samira; Faghihi, Reza; Taheri, Mehran

    2013-04-01

    In this study, the sensitivities and calibration factors of polystyrene (PS) to (220)Rn and (222)Rn have been investigated. The sensitivity of compact disks (CD/DVD) as thick polycarbonates (PC) to (220)Rn and (222)Rn has been also obtained by applying a new etching condition. Five different brands of X-ray radiology and MRI films with polystyrene base and four brands of CD/DVDs have been studied to assess their applicability as a passive detector for indoor radon monitoring. The comparison between the sensitivities of PS samples, CD/DVDs (as thick PC) and Lexan PC to (222)Rn and (220)Rn shows an improved sensitivity of PS over conventional PC currently being used as solid state nuclear track detectors (SSNTD). The sensitivity of X-ray radiology PS films to (222)Rn and (220)Rn was found to be 8.77±0.591 and 0.028±0.006 (cm(-2)kBq(-1)d(-1)m(3)). The sensitivities of MRI PS films to Rn-222 and Rn-220 was found to be 12.2±1.25 and 0.360±0.090 (cm(-2)kBq(-1)d(-1)m(3)). The CD/DVD PC found to have a sensitivity of 0.178±0.013 and 0.0024±0.00013 (cm(-2)kBq(-1)d(-1)m(3)) to (222)Rn and (220)Rn respectively.

  3. 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.

  4. Variable spacial and seasonal hazards of airborne radon

    NASA Astrophysics Data System (ADS)

    Mose, Douglas G.; Mushrush, George W.

    The concentrations of indoor radon in the basements of homes located in northern Virginia average about 1.4 times the first-floor radon concentration. Basement indoor radon concentrations exhibit seasonal variations which can be related to home use patterns of the occupants. Little indoor radon difference was seen between homes that have concrete block basement walls and poured concrete basement walls, but homes that use oil or gas furnaces for heating have a 25% lower indoor radon than homes that use electrical heating systems. Particular geological units seem to be associated with elevated indoor radon concentrations, and several units are associated with indoor radon concentrations that exceed 4 pCi l-1 (the U.S. Environmental Agency "Action Level") in more than 40% of the homes. Comparative studies between indoor radon and total-gamma aeroradioactivity show that aeroradioactivity can be accurately used to estimate community radon hazards.

  5. Probability mapping of indoor radon-prone areas using disjunctive kriging.

    PubMed

    Raspa, G; Salvi, F; Torri, G

    2010-01-01

    After a reference to the use of maps of radon-prone areas for indoor radon risk management, and to the methods used to produce them, there is a brief illustration of the geostatistical method of disjunctive kriging (DK) introduced by G. Matheron as a substitute for conditional expectation. There are some good reasons of using this method for the mapping of radon-prone areas as follows: (1) spatial correlation is exploited; (2) unbiasedness is conserved even in the conditions of quasi-stationarity; (3) lognormality of the data is not required; (4) choosing the point estimation allows drawing up smooth probability maps. An application of DK is also presented for the production of probability maps in a campaign of indoor radon measurements conducted by Institute for Environmental Protection and Research, in the provinces of Rome and Viterbo (Central Italy). In the application, it is assessed in particular how much the spatial correlation, even though low, influences the results.

  6. 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…

  7. Comprehensive survey of household radon gas levels and risk factors in southern Alberta

    PubMed Central

    Stanley, Fintan K.T.; Zarezadeh, Siavash; Dumais, Colin D.; Dumais, Karin; MacQueen, Renata; Clement, Fiona; Goodarzi, Aaron A.

    2017-01-01

    Background: The inhalation of naturally occurring radon (222Rn) gas from indoor air exposes lung tissue to α-particle bombardment, a highly mutagenic form of ionizing radiation that damages DNA and increases the lifetime risk of lung cancer. We analyzed household radon concentrations and risk factors in southern Alberta, including Calgary, the third-largest Canadian metropolis. Methods: A total of 2382 residential homes (2018 in Calgary and 364 in surrounding townships) from an area encompassing 82% of the southern Alberta population were tested for radon, per Health Canada guidelines, for at least 90 days (median 103 d) between 2013 and 2016. Participants also provided home metrics (construction year, build type, foundation type, and floor and room of deployment of the radon detector) via an online survey. Homes that were subsequently remediated were retested to determine the efficacy of radon reduction techniques in the region. Results: The average indoor air radon level was 126 Bq/m3, which equates to an effective absorbed radiation dose of 3.2 mSv/yr. A total of 1135 homes (47.6%) had levels of 100 Bq/m3 or higher, and 295 homes (12.4%) had levels of 200 Bq/m3 or higher; the range was less than 15 Bq/m3 to 3441 Bq/m3. Homes built in 1992 or later had radon levels 31.5% higher, on average, than older homes (mean 142 Bq/m3 v. 108 Bq/m3). For 90 homes with an average radon level of 575 Bq/m3 before mitigation, radon suppression successfully reduced levels to an average of 32.5 Bq/m3. Interpretation: Our findings show that radon exposure is a genuine public health concern in southern Alberta, suggest that modern building practices are associated with increased indoor air radon accumulation, legitimatize efforts to understand the consequences of radon exposure to the public, and suggest that radon testing and mitigation are likely to be impactful cancer prevention strategies.

  8. 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.

  9. Shelter and indoor air in the twenty-first century--radon, smoking, and lung cancer risks

    SciTech Connect

    Fabrikant, J.I. )

    1990-06-01

    Recognition that radon and its daughter products may accumulate to high levels in homes and in the workplace has led to concern about the potential lung cancer risk resulting from indoor domestic exposure. While such risks can be estimated with current dosimetric and epidemiological models for excess relative risks, it must be recognized that these models are based on data from occupational exposure and from underground miners' mortality experience. Several assumptions are required to apply risk estimates from an occupational setting to the indoor domestic environment. Analyses of the relevant data do not lead to a conclusive description of the interaction between radon daughters and cigarette smoking for the induction of lung cancer. The evidence compels the conclusion that indoor radon daughter exposure in homes represents a potential life-threatening public health hazard, particularly in males, and in cigarette smokers. Resolution of complex societal interactions will require public policy decisions involving the governmental, scientific, financial, and industrial sectors. These decisions impact the home, the workplace, and the marketplace, and they extend beyond the constraints of science. Risk identification, assessment, and management require scientific and engineering approaches to guide policy decisions to protect the public health. Mitigation and control procedures are only beginning to receive attention. Full acceptance for protection against what could prove to be a significant public health hazard in the twenty-first century will certainly involve policy decisions, not by scientists, but rather by men and women of government and law.

  10. 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.

  11. Indoor radon concentrations in Poland as determined in short-term (two-day) measurements.

    PubMed

    Zalewski, M; Mnich, Z; Karpińska, M; Kapała, J; Zalewski, P

    2001-01-01

    The aim of the present work was to obtain a pattern of 222Rn concentration distributions in typical buildings in Poland. In the investigations, the environmental passive detectors of the PICO-RAD type were used. The study encompassed buildings that were typical for Poland. The distribution of airborne 222Rn concentrations indoors is of a log-normal type. A total 1171 detectors were measured. Measurements were made in 319 basements, the remaining 852 measurements were carried out in the inhabited part of the houses. The radon concentrations in the basements in Bq x m(-3) ranged from 6 to 1300 with the arithmetic mean AM = 60, geometric mean GM = 30 and median M = 28, whereas those in the inhabited parts of the house (above the ground level) were: AM = 25, GM = 17 and M = 16 with the highest record value of 420.

  12. 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

  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. alpha-Radiation dose at bronchial bifurcations of smokers from indoor exposure to radon progeny.

    PubMed Central

    Martell, E A

    1983-01-01

    Synergistic interactions of indoor radon progeny with the cigarette smoking process have been evaluated experimentally. Smoking enhances the air concentration of submicron particles and attached radon decay products. Fractionation in burning cigarettes gives rise to the association of radon progeny with large particles in mainstream cigarette smoke, which are selectively deposited in "hot spots" at bronchial bifurcations. Because smoke tars are resistant to dissolution in lung fluid, attached radon progeny undergo substantial radioactive decay at bifurcations before clearance. Radon progeny inhaled during normal breathing between cigarettes make an even larger contribution to the alpha-radiation dose at bifurcations. Progressive chemical and radiation damage to the epithelium at bifurcations gives rise to prolonged retention of insoluble 210Pb-enriched smoke particles produced by tobacco trichome combustion. The high incidence of lung cancer in cigarette smokers is attributed to the cumulative alpha-radiation dose at bifurcations from indoor radon and thoron progeny--218Po, 214Po, 212Po, and 212Bi--plus that from 210Po in 210Pb-enriched smoke particles. It is estimated that a carcinogenic alpha-radiation dose of 80-100 rads (1 rad = 0.01 J/kg = 0.01 Gy) is delivered to approximately equal to 10(7) cells (approximately equal to 10(6) cells at individual bifurcations) of most smokers who die of lung cancer. PMID:6572389

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

    SciTech Connect

    Hopke, P.K.

    1990-01-01

    The chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon must be understood if the exposure to radon progeny is to be fully assessed. Two areas of radon progeny behavior will be studied; laboratory studies and studies in actual indoor environments. Laboratory studies include: Measure the neutralization rate of {sup 218}Po{sup +}{sub x} in O{sub 2} at low radon concentrations. Determine the formation rates of {center dot}OH, {center dot}O, or other oxidative radicals formed by the radiolysis of air following radon decay. Examine the formation of particles by the radiolytic oxidation of substances and measure the rate of ion-induced nucleation in the sulfuric acid-water vapor system with and without NH{sub 3} additions using a thermal diffusion cloud chamber. Exposure studies include: Initiate measurements of the activity size distribution in actual homes with occupants present; 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 acquire the components and begin to develop the methodology to determine the hygroscopicity of the indoor aerosol.

  16. 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) ...

  17. Indoor radon progeny aerosol size measurements in urban, suburban, and rural regions

    SciTech Connect

    Tu, K.W.; Knutson, E.O.; George, A.C. )

    1991-01-01

    By using direct and indirect methods, the authors conducted size distribution measurements of radon progeny particles in a variety of indoor environments in urban, suburban, and rural areas. The radon progeny particle size distribution owing to indoor activities has two definable source categories: (1) gas combustion from stoves and kerosene heaters - particles were found to be smaller than 0.1 {mu}m in diameter, mostly in the range 0.02-0.08 {mu}m; and (2) cigarette smoking and food frying - particles were found to be larger, in the size range 0.1-0.2 {mu}m. The radon progeny particle size distribution, without significant indoor activities, such as cooking, was found to be larger in rural areas than in urban or suburban areas. The modal diameters of the size spectra in the rural areas were two to three times larger than those in urban or suburban areas, around 0.3-0.4 bs. 0.1-0.2 {mu}m. Results obtained by applying the attachment theory to the measured number-weighted size spectra from an electrical aerosol size analyzer support this finding. These results, if confirmed by more extensive studies, will be useful for the assessment of the risk from the inhalation of radon progeny in various indoor environments.

  18. 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...

  19. 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.

  20. Machine learning for the analysis of indoor radon distribution, compared with ordinary kriging.

    PubMed

    Pegoretti, S; Verdi, L

    2009-12-01

    Having a reliable forecasting tool is necessary to correctly identify radon prone areas, especially in cases where the variable of interest is the indoor radon concentration. An appropriate characterisation of the features of the buildings becomes fundamental. In this work, the results obtained (in global and local scale) using the following approaches for estimating the concentration of indoor radon at locations that were not sampled were compared: geostatistical model, based on ordinary kriging, and machine learning (ML) technique. In the first case, algorithms designed for the specific and fine treatment (by modelling the variographic structure) of the spatial component of the phenomenon were used, whereas in the second case a model that can also exploit information linked to other variables that characterise each single dwelling in which the measure was conducted was used. For locations having large errors, the ML approach provides better results, due to the information related to 'soil contact' and 'building material'.

  1. Study of indoor radon concentrations and associated health risks in the five districts of Hazara division, Pakistan.

    PubMed

    Khan, Fayaz; Ali, Nawab; Khan, Ehsan U; Khattak, Nimat U; Raja, Iftikhar A; Baloch, Muzahir A; Rajput, Muhammad U

    2012-11-01

    A total of 200 indoor air samples were collected to measure radon concentration levels and its contribution to the mean effective doses during different seasons of the period 2009-2010 at different sites of the five districts of Hazara division, Pakistan. The major portion of the region is mountainous and is full of thick forests which receives heavy snow fall in winter. The need for conducting the present survey relied on the fact that occupants spend their lives in poorly ventilated indoor environments of the region, especially in the winter season when they use wood fire inside their residences. The measurements of indoor air samples were taken with RAD-7, a solid state α-detector. Radon concentrations in the whole region range from 41 Bq m(-3) to 254 Bq m(-3) with a geometric mean of 128 Bq m(-3). Radon progenies were measured with a surface barrier detector through alpha spectroscopy from which the Equilibrium Factor (EF) for radon and Radon Decay Products (RDPs) for the smoke-bearing as well as smoke-free indoor environments were deduced. The respective mean values of EF were calculated as 0.49 ± 0.08 and 0.40 ± 0.07. The mean effective doses from indoor air of Abbottabad, Mansehra, Haripur, Battgram and Kohistan districts were calculated as 3.5 ± 1.2, 3.7 ± 0.7, 3.9 ± 1.0, 3.6 ± 1.1 and 3.9 ± 0.7 mSv a(-1) respectively, with the maximum value of 5.1 ± 1.8 mSv a(-1) in Kohistan district during winter and the minimum value of 2.9 ± 1.0 mSv a(-1) in Abbottabad district during summer. The annual exposure dose to the inhabitants of the locality lies below the upper bound of 10 mSv a(-1), as recommended by ICRP-65, and may not pose any significant threat to the public health.

  2. 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.

  3. Uranium-238 and thorium-232 series concentrations in soil, radon-222 indoor and drinking water concentrations and dose assessment in the city of Aldama, Chihuahua, Mexico.

    PubMed

    Colmenero Sujo, L; Montero Cabrera, M E; Villalba, L; Rentería Villalobos, M; Torres Moye, E; García León, M; García-Tenorio, R; Mireles García, F; Herrera Peraza, E F; Sánchez Aroche, D

    2004-01-01

    High-resolution gamma spectrometry was used to determine the concentration of 40K, 238U and 232Th series in soil samples taken from areas surrounding the city of Aldama, in Chihuahua. Results of indoor air short-time sampling, with diffusion barrier charcoal detectors, revealed relatively high indoor radon levels, ranging from 29 to 422 Bq/m3; the radon concentrations detected exceeded 148 Bq/m3 in 76% of the homes tested. Additionally, liquid scintillation counting showed concentrations of radon in drinking water ranging from 4.3 to 42 kBq/m3. The high activity of 238U in soil found in some places may be a result of the uranium milling process performed 20 years ago in the area. High radon concentrations indoor and in water may be explained by assuming the presence of uranium-bearing rocks underneath of the city, similar to a felsic dike located near Aldama. The estimated annual effective dose of gamma radiation from the soil and radon inhalation was 3.83 mSv.

  4. 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.

  5. 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.

  6. 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).

  7. Measurement and apportionment of radon source terms for modeling indoor environments. Annual progress report, March 1991--February 1992

    SciTech Connect

    Harley, N.H.

    1992-02-01

    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. The dosimetry has been extended to include organs other than the lung.

  8. Measurements of the deposition rates of radon daughters on indoor surfaces

    SciTech Connect

    Toohey, R.E.; Essling, M.A.; Rundo, J.; Hengde, W.

    1983-01-01

    The deposition rates of radon daughters on indoor surfaces have been measured by exposing the window of a proportional counter to the air of a house with high concentrations of radon and its daughters. Deposition velocities for unattached RaA and RaB of approximately 4 mm sec/sup -1/ were obtained by dividing the deposition rates by the concentrations of unattached daughters in the air. These results agree with those obtained by other workers but are dependent on the assumptions made about the fractions of the daughters which are attached to the atmospheric aerosol.

  9. 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.

  10. 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.

  11. 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.

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

    PubMed Central

    Arvela, H.; Holmgren, O.; Hänninen, P.

    2016-01-01

    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. PMID:25899611

  13. 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.

  14. 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.

  15. Mitigation of elevated indoor radon gas resulting from underground air return usage.

    PubMed

    Kearfott, K J; Metzger, R L; Kraft, K R; Holbert, K E

    1992-12-01

    Underground air returns have been found to be active transportation pathways for radon gas entry into homes. Several homes for which underground air returns were contributing to elevated indoor 222Rn concentrations were evaluated for possible mitigation. Two houses with such problems were successfully mitigated by inserting flexible ducts into the returns. In one of these houses, the initial mitigation attempt resulted in an exacerbation of the problem due to leakage of the ducting. This was solved by re-sleeving the returns using a stronger material. Mitigation of elevated indoor radon gas caused by use of underground air returns by inserting flexible ducts is not possible for all situations, especially those for which the returns are small, filled with debris, misaligned, or inaccessible.

  16. 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.

  17. Follow-up durability measurements and mitigation-performance improvement tests in 38 Eastern Pennsylvania houses having indoor radon-reduction systems. Final report, Oct 89-Feb 90

    SciTech Connect

    Findlay, W.O.; Robertson, A.; Scott, A.G.

    1991-03-01

    The report gives results of follow-up tests in 38 difficult-to-mitigate Pennsylvania houses where indoor radon reduction systems had been installed 2 to 4 years earlier. Objectives were to assess system durability, methods for improving performance, and methods for reducing installation and operating costs. The durability tests indicated that the 38 systems have not experienced any significant degradation in indoor radon levels or in system flows/suctions, except in 6 houses where system fans failed, and in houses where homeowners turned off the systems. Tests to improve performance indicated that nearly all of the elevated residual radon levels are due to re-entrainment back into the house of very-high-radon exhaust gas from the soil depressurization systems, and to radon release from well water. Tests to reduce system costs showed that premitigation sub-slab suction field measurements can help prevent installation of too many suction pipes when communication is good, but suggest a need for too many pipes when communication is poor. Soil depressurization fans could not be turned down to the extent expected in some systems that were over-designed. Between 6 and 42% of the exhausted air was withdrawn from the house.

  18. {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.

  19. S. 792: This Act may be cited as the Indoor Radon Abatement Reauthorization Act of 1991, introduced in the United States Senate, One Hundred Second Congress, First Session, April 9, 1991

    SciTech Connect

    Not Available

    1991-01-01

    This bill was introduced into the Senate of the United States on April 9, 1991 to reauthorize the Indoor Radon Abatement Act of 1988. This legislation amends the Toxic Substances Control Act. The following sections are clarified and expanded: Priority radon areas; Citizens guide; Model construction standards; Technical assistance; Grant assistance; Radon in schools; Regional radon training centers; Federal buildings; Radon information; Mandatory radon proficiency program; Medical community outreach; Federal Housing; National radon educational efforts; Radon in work places; and Citizens suits.

  20. A COMPARATIVE STUDY OF DIURNAL VARIATION OF RADON AND THORON CONCENTRATIONS IN INDOOR ENVIRONMENT.

    PubMed

    Pant, Preeti; Kandari, Tushar; Prasad, Mukesh; Ramola, R C

    2016-10-01

    The diurnal measurements of radon and thoron concentrations were performed in the indoor environment of Nuclear Research Laboratory, Badshahi Thaul, Tehri Garhwal, Uttarakhand, India by using AlphaGUARD, Portable Radon Monitor (SMART RnDuo) and RAD7. Using AlphaGUARD, the radon concentration was found to vary from 8 to 94 Bq m(-3) with an average of 41.5±22.2 Bq m(-3) Using Portable Radon Monitor (SMART RnDuo), the concentration was found to vary from 2 to 101 Bq m(-3) with an average of 41.7±23.6 Bq m(-3), and with RAD7, the concentration was found to vary from 3 to 99 Bq m(-3) with an average of 40±20.3 Bqm(-3) While the thoron concentration using Portable Radon Monitor (SMART RnDuo) was found to vary from 4 to 65 Bq m(-3) with an average of 17.3±12.9 Bqm(-3), and using RAD7, the concentration was found to vary from 5 to 90 Bq m(-3) with an average of 29.8±17.3 Bq m(-3).

  1. 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).

  2. 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).

  3. Radon in Schools

    MedlinePlus

    ... is a critical component of any comprehensive indoor air quality (IAQ) management program, l earn how to manage ... provide feedback, or report a problem. Radon Indoor Air Quality Home Page Radon Home Local Radon Zones and ...

  4. 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.

  5. 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.

  6. Assessment of external gamma exposure and radon levels in a dwelling constructed with phosphogypsum plates.

    PubMed

    Máduar, M F; Campos, M P; Mazzilli, B P; Villaverde, F L

    2011-06-15

    Phosphogypsum, a fertilizer industry by-product, is being worldwide stockpiled, posing environmental concerns. Since this material contains natural radionuclides in significant concentrations, its use as a building material has radiological implications. In order to confirm the feasibility of the use of a new material mainly composed by phosphogypsum, an experimental house was built, having some of its rooms entirely lined with this material. Measurements of samples of phosphogypsum plates from different origins resulted in values of 0.2 to 2.6 for the external radiation index, thus justifying a more detailed investigation. In this paper, the application of a previously developed computational model to forecast external doses indoors is described. A comprehensive radiological evaluation is being performed, including measurement of the external gamma exposure and radon concentrations in one of the rooms of the house. The results show that the annual increment in the effective dose to an inhabitant of the house will remain below the 1 mSv limit for every reasonable scenario. The radon measurements were carried out over a period of 18 months, in order to determine the long-term average levels of the indoor radon concentrations. The results obtained are below 200 Bq m(-3), the recommended investigation level for radon.

  7. 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

  8. 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.

  9. [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.

  10. 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

  11. Indoor radon measurements in south west England explained by topsoil and stream sediment geochemistry, airborne gamma-ray spectroscopy and geology.

    PubMed

    Ferreira, Antonio; Daraktchieva, Zornitza; Beamish, David; Kirkwood, Charles; Lister, T Robert; Cave, Mark; Wragg, Joanna; Lee, Kathryn

    2016-05-20

    Predictive mapping of indoor radon potential often requires the use of additional datasets. A range of geological, geochemical and geophysical data may be considered, either individually or in combination. The present work is an evaluation of how much of the indoor radon variation in south west England can be explained by four different datasets: a) the geology (G), b) the airborne gamma-ray spectroscopy (AGR), c) the geochemistry of topsoil (TSG) and d) the geochemistry of stream sediments (SSG). The study area was chosen since it provides a large (197,464) indoor radon dataset in association with the above information. Geology provides information on the distribution of the materials that may contribute to radon release while the latter three items provide more direct observations on the distributions of the radionuclide elements uranium (U), thorium (Th) and potassium (K). In addition, (c) and (d) provide multi-element assessments of geochemistry which are also included in this study. The effectiveness of datasets for predicting the existing indoor radon data is assessed through the level (the higher the better) of explained variation (% of variance or ANOVA) obtained from the tested models. A multiple linear regression using a compositional data (CODA) approach is carried out to obtain the required measure of determination for each analysis. Results show that, amongst the four tested datasets, the soil geochemistry (TSG, i.e. including all the available 41 elements, 10 major - Al, Ca, Fe, K, Mg, Mn, Na, P, Si, Ti - plus 31 trace) provides the highest explained variation of indoor radon (about 40%); more than double the value provided by U alone (ca. 15%), or the sub composition U, Th, K (ca. 16%) from the same TSG data. The remaining three datasets provide values ranging from about 27% to 32.5%. The enhanced prediction of the AGR model relative to the U, Th, K in soils suggests that the AGR signal captures more than just the U, Th and K content in the soil. The

  12. ASSESSMENT OF THE EFFECTS OF WEATHERIZATION ON RESIDENTIAL RADON LEVELS

    EPA Science Inventory

    The report gives results of an assessment of the effects of weatherization on residential radon levels. For this assessment, time-integrated radon measurements were taken for 30- to 45-day periods both before and after weatherization in 32 Retro-Tech homes, 28 advanced homes, and...

  13. 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.

  14. A practical E-PERM (electret passive environmental radon monitor) system for indoor 222Rn measurement.

    PubMed

    Kotrappa, P; Dempsey, J C; Ramsey, R W; Stieff, L R

    1990-04-01

    The technical and scientific basis for the measurement of indoor 222Rn concentration using an E-PERM (Electret passive environmental radon monitor) has been described in our earlier work. The purpose of this paper is to describe further development of a practical and convenient system that can be used routinely for indoor 222Rn measurement. The ion chamber is now made of electrically conducting plastic to minimize the response from natural gamma radiation. A spring-loaded shutter method is used to cover and uncover the electret from outside the chamber. The electret voltage reader has been modified to improve the accuracy and the ease in operation. The calibration, performance, error analysis, and lower limits of detection for these standardized versions of E-PERMs are also described.

  15. The influence of meteorological parameters on soil radon levels in permeable glacial sediments.

    PubMed

    Sundal, Aud Venke; Valen, Vidar; Soldal, Oddmund; Strand, Terje

    2008-01-25

    The influence of meteorological parameters on soil radon concentrations in a permeable ice-marginal deposit in Kinsarvik, Norway, was investigated based on continuous measurements of soil radon concentrations, temperature, precipitation, wind speed, wind direction, air pressure and soil moisture content over a period of 10 months. The results show that the soil radon concentrations exhibit distinct seasonal and diurnal variations that predominantly are caused by changes in air temperature. Air flows between areas of different elevation occur in the ice-marginal deposit due to temperature differences between soil air and atmospheric air, and instantaneous changes in air flow direction were recorded when the atmospheric air temperature reached the average annual air temperature. Air pressure was found to be the second most important parameter influencing soil radon concentrations, while no apparent effect of precipitation, wind speed, wind direction or soil moisture was observed. Seasonal variations in indoor and soil radon levels were also investigated in a glaciofluvial deposit located 40 km southwest of Kinsarvik, and the close correlation between the seasonal variation patterns observed in the two areas suggests that the results of the Kinsarvik study also might be applicable to other areas of highly permeable building grounds where differences in terrain elevation exist.

  16. Ultra-low level radon assays in gases

    SciTech Connect

    Liu, Xin Ran

    2015-08-17

    The SuperNEMO experiment aims to search for the neutrinoless double beta decay (0νβ β) to T{sub 1{sub /{sub 2}}}(0ν) > 10{sup 26} years, this corresponds to an effective neutrino mass of 50-100 meV. The extremely rare event rate means the minimisation of background is of critical concern. The stringent strategy instigated to ensure detector radiopurity is outlined here for all construction materials. In particular the large R&D programme undertaken to reach the challengingly low level of radon, < 0.15 mBq/m{sup 3}, required inside the SuperNEMO gaseous tracker will be detailed. This includes an experiment designed to measure radon diffusion through various materials. A “Radon Concentration Line” (RnCL) was developed to be used in conjunction with a state-of-the-art radon detector in order to achieve world leading sensitivity to {sup 222}Rn content in large gas volumes at the level of a few µBq/m{sup 3}. A radon purification system was developed and installed which has demonstrated radon suppression by several orders of magnitude depending on the carrier gas. This apparatus has now been commissioned and measurements of cylindered gas have been made to confirm radon suppression by a factor 20 when using nitrogen as the carrier gas. The results from measurements of radon content in various gases, used inside SuperNEMO, using the RnCL will be presented.

  17. High indoor radon concentrations in an alpine region of western Tyrol

    SciTech Connect

    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 Oetztaler Ache and Hairlachbach, geologically in alluvial fan of a giant rock slide of granitic gneisses (area A, median of annual means on the ground floors: 1,868 Bq m{sup {minus}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{sup {minus}3}). On the basis of these medians, the annual exposures were calculated according to the ICRP model (area A: 58.8 x 10{sup 5} Bq h m{sup {minus}3}; area B: 5.7 x 10{sup 5} Bq h m{sup {minus}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). 7 refs., 3 figs., 3 tabs.

  18. 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).

  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.

  20. 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

  1. 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 ...

  2. 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...

  3. On indoor radon contamination monitoring with SSNTDs: Experimental results concerning plate-out and self-plate-out effects

    NASA Astrophysics Data System (ADS)

    Bigazzi, G.; Hadler, J. C.; Paulo, S. R.

    1989-08-01

    Measurements of the alpha activities of 222Rn and its daughters were performed, both inside a glass recipient and in closed rooms, employing SSNTDs (CR-39 and nuclear emulsion). The experimental results presented here show that plate-out and self-plate-out effects should be taken into account when SSNTDs are employed in indoor radon contamination monitoring.

  4. Radon levels in groundwaters and natural radioactivity in soils of the volcanic region of La Garrotxa, Spain.

    PubMed

    Moreno, V; Bach, J; Baixeras, C; Font, Ll

    2014-02-01

    Groundwater radon level and soil radionuclide concentration have been measured in the volcanic region of La Garrotxa (Catalonia, Spain) to further research on the origin and dynamics of high radon levels over volcanic materials found in this region. Water samples from different aquifers have been collected from wells and springs and the water radon levels obtained have been lower than 30 Bq l(-1). Soil samples have been collected from different geological formations (volcanic and non-volcanic), being Quaternary sedimentary deposits those that have presented the highest mean values of (40)K, (226)Ra and (232)Th concentrations (448 ± 70 Bq kg(-1), 35 ± 5 Bq kg(-1) and 38 ± 5 Bq kg(-1), respectively). Additionally, indoor/outdoor terrestrial radiation absorbed dose rate in air have been measured to better characterize the region from the radiological point of view. Terrestrial radiation absorbed dose rates measurement points have been chosen on the basis of geological and demographical considerations and the results obtained, from 27 to 91 nGy h(-1), show a clear relation with geological formation materials. The highest terrestrial gamma absorbed dose rate is observed over Quaternary sedimentary deposits as well. All these results help to better understand previous surveys related with indoor and outdoor radon levels and to reinforce the hypotheses of a radon transport through the fissure network.

  5. Soil radon measurements in the Canadian cities.

    PubMed

    Chen, J; Moir, D; MacLellan, K; Leigh, E; Nunez, D; Murphy, S; Ford, K

    2012-08-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. Information on indoor radon concentrations is required to assess the lung cancer burden due to radon exposure. Since radon in soil is believed to be the main source of radon in homes, measurements of soil gas radon concentrations can be used to estimate variations in radon potential of indoor environments. This study reports surveys of natural background variation in soil radon levels in four cities, Montreal, Gatineau, Kingston and the largest Canadian city of Toronto. A total of 212 sites were surveyed. The average soil gas radon concentrations varied significantly from site to site, and ranged from below detection limit to 157 kBq m(-3). For each site, the soil radon potential (SRP) index was determined with the average soil radon concentration and average soil permeability measured. The average SRP indexes are 20±16, 12±11, 8±9 and 12±10 for Montreal, Gatineau, Kingston and Toronto, respectively. The results provide additional data for the validation of an association between indoor and soil radon potentials and for the development of radon potential map of Canada.

  6. Thoron activity level and radon measurement by a nuclear track detector.

    PubMed

    Planinić, J; Faj, Z; Vuković, B

    1993-03-01

    Radon activity concentrations in the air were measured with LR-115 nuclear track detectors at three locations in Osijek. The respective equilibrium factors and the effective dose equivalents were determined. Indoor concentrations were from 9.8 to 58.2 Bq m-3 and relative errors of the track etching method were near 19 per cent. The indoor alpha potential energy of the radon and thoron progenies was measured with an ISD detector. Independent measurements, performed with a Radhome semiconductor detector, showed that the indoor thoron concentration was nearly 20 per cent of the radon one.

  7. 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.

  8. Radon measurement and mitigation activity in Finland.

    PubMed

    Valmari, T; Arvela, H; Reisbacka, H; Holmgren, O

    2014-07-01

    Radon prevention, measurement and mitigation activities have been increasing in Finland during the 2000s. Nowadays, many municipal authorities, especially those located in high-radon areas, require radon prevention measures. This has activated radon measurements. Owners of new houses having radon piping installed under the floor slab are the most active group to measure and reduce the found high-radon values. Their radon awareness is apparently better than on the average, and the existing piping makes it easier and cheaper to reduce the radon levels. Local campaigns involving invitation flyers mailed to the residents have been a cost-effective means to activate measurements of older houses. So far 116,611 dwellings in low-rise residential buildings have been measured. At least 15% of the 16,860 dwellings found to exceed the reference level of 400 Bq m(-3) had their indoor radon level reduced below that.

  9. Geologic controls on radon

    SciTech Connect

    Gates, A.E.; Gundersen, L.C.S.

    1992-01-01

    This text provides a review of recent research on geological controls of [sup 222]Rn concentrations in soil gas in relation to the problem of high indoor radon concentrations in houses. The importance of the subject matter is highlighted in the preface by the observation that the US Environmental Protection Agency (EPA) estimates that 15,000 to 25,000 deaths result from radon-induced lung cancer each year in the United States. The text contains 8 Chapters: (1) Geology of radon in the United States; (2) Sensitivity of soil radon to geology and the distribution of radon and uranium in the Hylas Zone Area, Virginia; (3) Geologic and environmental implications of high soil-gas radon concentrations in The Great Valley, Jefferson and Berkeley Counties, West Virginia; (4) Soil radon distribution in glaciated areas: an example from the New Jersey Highlands; (5) Radon in the coastal plain of Texas, Alabama, and New Jersey; (6) Effects of weather and soil characteristics on temporal variations in soil-gas radon concentrations; (7) A theoretical model for the flux of radon from rock to ground water; (8) The influence of season, bedrock, overburden, and house construction on airborne levels of radon in Maine homes. The individual chapters are written by different authors in the form of self-contained research papers, each of which is followed by a comprehensive list of references.

  10. A creeping suspicion about radon

    SciTech Connect

    Alderson, L.

    1994-10-01

    Who would expect an odorless, invisible gas that occurs nearly everywhere on earth to cause such trouble Yet radon, the gas emitted by decay of uranium in the earth's crust, is one of America's most significant environmental risks, according to the EPA, which estimates that residential radon levels lead to approximately 13,600 lung cancer deaths each year. A new National Cancer Institute analysis of multiple studies of miners confirms early estimates, putting the number at 15,000. No other risk comes close, not even environmental tobacco smoke, which is estimates to cause some 3,000 deaths each year. Hot debate surrounds the assessment of risk from radon exposure to Americans via indoor air and water supplies. The primary culprit is not radon gas itself, but its decay products, including polonium-214 and polonium-218, which have long half-lives and emit alpha particles - positively charged particles - and lung cancer when inhaled. Radon seeps into homes from the ground or is present in water supplies. Waterborne radon may be inhaled as radon or its progeny during household use - cooking or showering - or it may be ingested. But the EPA estimates that water sources contribute only about 5% of total airborne radon exposure, leaving indoor air as the worst offender. While the EPA estimates that approximately 200 cancer cases per year result from exposure to radon from public groundwater systems, estimates of annual lung cancer deaths from indoor air radon range from 7,000 to 30,000.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Radon levels in Romanian caves: an occupational exposure survey.

    PubMed

    Cucoş Dinu, Alexandra; Călugăr, Monica I; Burghele, Bety D; Dumitru, Oana A; Cosma, Constantin; Onac, Bogdan P

    2016-10-01

    A comprehensive radon survey has been carried out in seven caves located in the western half of Romania's most significant karst regions. Touristic and non-touristic caves were investigated with the aim to provide a reliable distribution of their radon levels and evaluate the occupational exposure and associated effective doses. Radon gas concentrations were measured with long-term diffusion-type detectors during two consecutive seasons (warm and cold). All investigated caves exceed the European Union reference level of radon gas at workplaces (300 Bq/m(3)). The radon concentration in these caves ranges between 53 and 2866 Bq/m(3), reflecting particular cave topography, season-related cave ventilation, and complex tectonic and geological settings surrounding each location. Relatively homogeneous high radon levels occur in all investigated touristic caves and in Tăuşoare and Vântului along their main galleries. Except for Muierii, in all the other caves radon levels are higher during the warm season, compared to the cold one. This suggests that natural cave ventilation largely controls the underground accumulation of radon. The results reported here reveal that the occupational exposure in Urşilor, Vadu Crişului, Tăuşoare, Vântului, and Muierii caves needs to be carefully monitored. The effective doses to workers vary between an average of 0.25 and 4.39 mSv/year depending on the measuring season. The highest values were recorded in show caves, ranging from 1.15 to 6.15 mSv/year, well above the European recommended limit, thus posing a potential health hazard upon cave guides, cavers, and scientists.

  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. 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.

  19. FOLLOW-UP ALPHA-TRACK MONITORING IN 40 EASTERN PENNSYLVANIA HOUSES WITH INDOOR RADON REDUCTION SYSTEMS (WINTER 1988-89)

    EPA Science Inventory

    The report gives results of 4-month-long alpha-track detector (ATD) measurements of indoor radon concentrations, completed during the winter of 1988-89 in 38 of 40 houses where radon reduction techniques had been installed 2-4 years previously during an earlier EPA project. The t...

  20. FOLLOW-UP ANNUAL ALPHA-TRACK MONITORING IN 40 EASTERN PENNSYLVANIA HOUSES WITH INDOOR RADON REDUCTION SYSTEMS (DECEMBER 1988 - DECEMBER 1989)

    EPA Science Inventory

    The report gives results of 12-month-long alpha-track detector (ATD) measurements of indoor radon concentrations, between December 1988 and December 1989 in the living areas of 38 of 40 houses where radon reduction techniques had been installed 2-4 years earlier in a previous EPA...

  1. 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.

  2. 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.

  3. 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.

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

    SciTech Connect

    Not Available

    1983-01-01

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

  5. 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

  6. 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

  7. 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.

  8. Radon reduction and radon-resistant construction demonstrations in New York. Final report, September 1986-June 1988

    SciTech Connect

    Nitschke, I.

    1989-01-01

    The report covers three tasks related to indoor radon: (1) the demonstration of radon reduction techniques in 8 houses in each of two uniquely different radon prone areas of the State of New York; (2) the evaluation and repair of 14 radon mitigation systems in houses mitigated 4 years earlier; and (3) the development and application of radon resistant new construction designs in 15 different houses. In applying radon reduction techniques in existing houses, techniques which were applicable in extremely porous soil were not as easily applied to houses built on granite ledge; combinations of techniques may be required in many difficult houses before an acceptable radon level can be achieved. During the study, basement pressurization was applied as a radon reduction technique for the first time. The radon resistant new construction designs should demonstrate effective methods of sealing out radon during construction; however, quality control problems prevalent in the construction industry may require additional laboratory tests for verification.

  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. Estimation of the residential radon levels and the annual effective dose in dwellings of Shiraz, Iran, in 2015

    PubMed Central

    Yarahmadi, Maryam; Shahsavani, Abbas; Mahmoudian, Mohammad Hassan; Shamsedini, Narges; Rastkari, Noushin; Kermani, Majid

    2016-01-01

    Introduction Radon is the second most important cause of lung cancer after smoking. Thus, the determination of indoor radon concentrations in dwellings and workplaces is an important public health concern. The purpose of this research was to measure the concentration of radon gas in residential homes and public places in the city of Shiraz and its relationship with the type and age of the buildings as well as the type of materials used to construct the building (brick, block). We also determined the radon dosages that occupants of the building would receive. Methods The present study is a descriptive-analytical and cross-sectional research that was conducted on the building’s indoor air in the city of Shiraz in 2015. Using geographic information system (GIS) software and a spatial sampling cell with an area of 25 square kilometers, 200 points were selected. In this study, we used passive diffusive samplers as Solid State Nuclear Track Detector (SSNTD) CR-39 polycarbonate films for three months in the winter. Sampling was conducted in accordance with the U.S. Environmental Protection Agency’s protocol. We determined the concentrations of radon gas at the time of sampling, and calibration factors were determined. The data were analyzed by IBM-SPSS, version 20, descriptive statistics, Kruskal-Wallis, and Mann–Whitney tests. Results This study showed that the average radon concentration was 57.6 ± 33.06 Bq/m3 in residential dwellings. The average effective dose was 1.45 mSv/y. The concentration of radon in 5.4% of the houses was found to be greater than 100 Bq/m3, which is above the level allowed by the World Health Organization (WHO). Conclusion Since radon is the second leading cause of lung cancer, it seems necessary to increase the public’s awareness of this issue and to take action to reduce radon in homes when the concentrations are above the WHO’s guideline. PMID:27504164

  11. 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

  12. 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

  13. Estimation of mean annual effective dose through radon concentration in the water and indoor air of Islamabad and Murree.

    PubMed

    Ali, N; Khan, E U; Akhter, P; Khan, F; Waheed, A

    2010-09-01

    Different samples of water, indoor air and soil gas have been collected from Islamabad (33 degrees 38'N, 73 degrees 09'E, altitude of 1760 ft.), the capital of Pakistan and Murree (33 degrees 53'N, 73 degrees 23'E, altitude of 7323 ft.), lying on a geological fault line and are analysed for the estimation of mean effective dose through radon concentrations by using RAD-7, a solid state alpha-detector. The variation of radon concentration in water, indoor air and soil gas in Islamabad region ranges from 25.90-158.40 kBq m(-3), 43.26-97.04 Bq m(-3) and 17.34-72.52 kBq m(-3), having mean values 88.63 kBq m(-3), 70.67 Bq m(-3) and 45.08 kBq m(-3)(,) respectively. It ranges from 1.64-10.20 kBq m(-3), 18.48-42.08 Bq m(-3) and 0.61-3.89 kBq m(-3) with mean values 4.38 kBq m(-3), 28.63 Bq m(-3) and 1.70 kBq m(-3)(,) respectively in Murree and its surroundings. The total mean annual effective doses from water and indoor air of Islamabad and Murree regions are 2.023 and 0.733 mSv a(-1), respectively. These doses are within the recommended limits of the world organisations.

  14. Geographical Correlations between Indoor Radon Concentration and Risks of Lung Cancer, Non-Hodgkin's Lymphoma, and Leukemia during 1999-2008 in Korea.

    PubMed

    Ha, Mina; Hwang, Seung-Sik; Kang, Sungchan; Park, No-Wook; Chang, Byung-Uck; Kim, Yongjae

    2017-03-24

    Indoor radon is the second most important risk factor for lung cancer and may also be a risk factor for hematopoietic cancers, particularly in children and adolescents. The present study measured indoor radon concentration nationwide at 5553 points during 1989-2009 and spatially interpolated using lognormal kriging. The incidences of lung cancer, non-Hodgkin's lymphoma (NHL), and leukemia, stratified by sex and five-year age groups in each of the 234 administrative regions in the country during 1999-2008, were obtained from the National Cancer Registry and used to calculate the standardized incidence ratios. After considering regional deprivation index values and smoking rates by sex in each region as confounding variables, the cancer risks were estimated based on Bayesian hierarchical modeling. We found that a 10 Bq/m³ increase in indoor radon concentration was associated with a 1% increase in the incidence of lung cancer in male and a 7% increase in NHL in female children and adolescents in Korea aged less than 20 years. Leukemia was not associated with indoor radon concentration. The increase in NHL risk among young women requires confirmation in future studies, and the radon control program should consider children and adolescents.

  15. Testing of indoor radon-reduction techniques in central Ohio houses: Phase 1 (Winter 1987-1988). Report for October 1987-August 1988 (Final)

    SciTech Connect

    Findlay, W.O.; Robertson, A.; Scott, A.G.

    1989-07-01

    The U.S. Environmental Protection Agency (EPA) has a program to demonstrate practical, cost-effective methods to reduce indoor radon concentrations in housing to 150 Bq/cu m (4 pCi/L) or less. The complete program will evaluate the full range of radon-reduction methods, i.e., house ventilation, sealing of entry routes, soil ventilation, radon removal from water, and air cleaning in the full range of housing substructure types and building styles, and geological conditions across the continental United States. The program described in the report demonstrated certain radon-reduction methods in housing and geology typical of southern Ohio in particular, and the central Great Plains States in general. The testing of radon-mitigation systems in Ohio houses is envisioned as taking place in two phases. The report describes Phase 1, which was carried out in 16 existing houses in the Dayton area during the 1987-1988 heating season.

  16. [Optimization of the indoor air conditioning in the places of excessive radon release].

    PubMed

    Malykhin, V M

    1994-01-01

    The experimental modelling covered ventilation and air purification as well as air pollution with radon and such derivatives as polonium-218b, lead-214 and bismuth-214. The modelling was designed for industrial conditions with higher radon release in technologic conversion at enterprises processing uranium. The investigators obtained some information to optimize air processing and to lower the workers exposure to radon and its derivatives.

  17. 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.

  18. Estimating population health risk from low-level environmental radon

    SciTech Connect

    Fisher, D.R.

    1980-01-01

    Although incidence of respiratory cancer is directly related to inhalation of radon and radon daughters, the magnitude of the actual risk is uncertain for members of the general population exposed for long periods to low-level concentrations. Currently, any such estimate of the risk must rely on data obtained through previous studies of underground-miner populations. Several methods of risk analysis have resulted from these studies. Since the breathing atmospheres, smoking patterns, and physiology are different between miners and the general public, overestimates of lung cancer risk to the latter may have resulted. Strong evidence exists to support the theory of synergistic action between alpha radiation and other agents, and therefore a modified relative risk model was developed to predict lung cancer risks to the general public. The model considers latent period, observation period, age dependency, and inherent risks from smoking or geographical location. A test of the model showed excellent agreement with results of the study of Czechoslovakian uranium miners, for which the necessary time factors were available. The risk model was also used to predict lung cancer incidence among residents of homes on reclaimed Florida phosphate lands, and results of this analysis indicate that over the space of many years, the increased incidence of lung cancer due to elevated radon levels may be indisgtinguishable from those due to other causes.

  19. 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).

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Radon in harvested rainwater at the household level, Palestine.

    PubMed

    Al-Khatib, Issam A; Al Zabadi, Hamzeh; Saffarini, Ghassan

    2017-04-01

    The main objective of this study was to assess Radon concentration in the harvested rainwater (HRW) at the household level in Yatta area, Palestine. HRW is mainly used for drinking as it is the major source of water for domestic uses due to water scarcity. Ninety HRW samples from the household cisterns were collected from six localities (a town and five villages) and Radon concentrations were measured. The samples were randomly collected from different households to represent the Yatta area. Fifteen samples were collected from each locality at the same day. RAD7 device was used for analysis and each sample was measured in duplicate. Radon concentrations ranged from 0.037 to 0.26 Bq/L with a mean ± standard deviation of 0.14 ± 0.06 Bq/L. The estimated annual effective radiation doses for babies, children and adults were all far below the maximum limit of 5 mSvy(-1) set by the National Council on Radiation Protection and Measurements.

  5. 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.

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

    PubMed

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

    2017-04-01

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

  7. 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.

  8. 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.

  9. Radon daughter considerations in a nuclear power plant

    SciTech Connect

    VanderMey, T.J.

    1987-07-01

    A boiling water reactor in the start-up phase experienced a significant number of personnel contamination monitor alarms caused by radon daughter plateout on hard hats, clothing, and shoes. Alarm frequencies were compared to environmental conditions and ventilation system operations to determine the effects of various factors on radon plateout. High normal ventilation, radon daughter concentrations in the plant were found to be similar to outdoor concentrations, and alarm frequencies were inversely related to relative humidity. When ventilation systems were shutdown, indoor radon levels and personnel contamination monitor alarm rates increased significantly. In this paper some suggestions for accounting for radon daughter contamination in monitoring and training programs are presented.

  10. 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.

  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. STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND THEIR PROGENY IN THE INDOOR ENVIRONMENT OF RAJPUR REGION OF UTTARAKHAND HIMALAYA.

    PubMed

    Kandari, Tushar; Aswal, Sunita; Prasad, Mukesh; Pant, Preeti; Bourai, A A; Ramola, R C

    2016-10-01

    In the present study, the measurements of indoor radon, thoron and their progeny concentrations have been carried out in the Rajpur region of Uttarakhand, Himalaya, India by using LR-115 solid-state nuclear track detector-based time-integrated techniques. The gas concentrations have been measured by single-entry pin-hole dosemeter technique, while for the progeny concentrations, deposition-based Direct Thoron and Radon Progeny Sensor technique has been used. The radiation doses due to the inhalation of radon, thoron and progeny have also been determined by using obtained concentrations of radon, thoron and their progeny in the study area. The average radon concentration varies from 75 to 123 Bq m(-3) with an overall average of 89 Bq m(-3) The average thoron concentration varies from 29 to 55 Bq m(-3) with an overall average of 38 Bq m(-3) The total annual effective dose received due to radon, thoron and their progeny varies from 2.4 to 4.1 mSv y(-1) with an average of 2.9 mSv y(-1) While the average equilibrium factor for radon and its progeny was found to be 0.39, for thoron and its progeny, it was 0.06.

  13. 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.

  14. Modeling and experimental examination of water level effects on radon exhalation from fragmented uranium ore.

    PubMed

    Ye, Yong-Jun; Dai, Xin-Tao; Ding, De-Xin; Zhao, Ya-Li

    2016-12-01

    In this study, a one-dimensional steady-state mathematical model of radon transport in fragmented uranium ore was established according to Fick's law and radon transfer theory in an air-water interface. The model was utilized to obtain an analytical solution for radon concentration in the air-water, two-phase system under steady state conditions, as well as a corresponding radon exhalation rate calculation formula. We also designed a one-dimensional experimental apparatus for simulating radon diffusion migration in the uranium ore with various water levels to verify the mathematical model. The predicted results were in close agreement with the measured results, suggesting that the proposed model can be readily used to determine radon concentrations and exhalation rates in fragmented uranium ore with varying water levels.

  15. PREFERENTIAL RADON TRANSPORT THROUGH HIGHLY PERMEABLE CHANNELS IN SOILS

    EPA Science Inventory

    The paper discusses preferential radon transport through highly permeable channels in soils. Indoor radon levels (that can pose a serious health risk) can be dramatically increased by air that is drawn into buildings through pipe penetrations that connect to permeable channels in...

  16. Use of an indoor air quality model (IAQM) to estimate indoor ozone levels.

    PubMed

    Hayes, S R

    1991-02-01

    Currently, outdoor ozone levels in many U.S. cities exceed the primary health-based national ambient air quality standard. While outdoor ozone levels are an important measure of the severity of those exceedances, people typically spend more than 80 percent of their time indoors, where ozone levels are lower. Indoor ozone levels range from 10 to 80 percent of outdoor levels, with many people receiving a substantial portion of their ozone exposure while indoors. This paper uses an indoor air quality model (IAQM) to estimate indoor ozone levels by microenvironment type (home, office, and vehicle) and configuration (windows open, windows closed, older construction, weatherized, and air conditioned). The formulation of IAQM is discussed, along with specification of model parameters for ozone. The multicompartment version of IAQM is described, with a single-compartment version used for the analyses. IAQM-calculated ozone indoor-outdoor ratios compare well with research-reported values. Results indicate that ozone peak-concentration indoor-outdoor ratios range as follows: home--0.65 (windows open), 0.36 (air conditioned), 0.23 (typical construction, windows closed), and 0.05 (energy-efficient construction, windows closed); office--0.82 (heating, ventilation and air conditioning systems supplying 100 percent outdoor air), 0.60 (typical HVAC), and 0.32 (energy-efficient HVAC); and vehicle--0.41 (85 mph), 0.33 (55 mph), and 0.21 (10 mph). Analysis results are presented to characterize IAQM's sensitivity to assumed model parameters.

  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. 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

  19. Geostatistical simulations for radon indoor with a nested model including the housing factor.

    PubMed

    Cafaro, C; Giovani, C; Garavaglia, M

    2016-01-01

    The radon prone areas definition is matter of many researches in radioecology, since radon is considered a leading cause of lung tumours, therefore the authorities ask for support to develop an appropriate sanitary prevention strategy. In this paper, we use geostatistical tools to elaborate a definition accounting for some of the available information about the dwellings. Co-kriging is the proper interpolator used in geostatistics to refine the predictions by using external covariates. In advance, co-kriging is not guaranteed to improve significantly the results obtained by applying the common lognormal kriging. Here, instead, such multivariate approach leads to reduce the cross-validation residual variance to an extent which is deemed as satisfying. Furthermore, with the application of Monte Carlo simulations, the paradigm provides a more conservative radon prone areas definition than the one previously made by lognormal kriging.

  20. RESIDENTIAL RADON RESISTANT CONSTRUCTION FEATURE SELECTION SYSTEM

    EPA Science Inventory

    The report describes a proposed residential radon resistant construction feature selection system. The features consist of engineered barriers to reduce radon entry and accumulation indoors. The proposed Florida standards require radon resistant features in proportion to regional...

  1. New-construction techniques and HVAC (heating, venting and air conditioning) overpressurization for radon reduction in schools

    SciTech Connect

    Witter, K.A.; Craig, A.B.; Saum, D.

    1988-04-01

    Construction of a school in Fairfax County, Virginia, is being carefully monitored since elevated indoor radon levels have been identified in many existing houses near the site. Soil-gas radon concentrations measured prior to pouring of the slabs were also indicative of a potential radon problem should the soil gas enter the school; however, subslab radon measurements collected thus far are lower than anticipated. In addition, the school's heating, ventilating, and air-conditioning (HVAC) system has been designed to operate continously in overpressurization to help reduce pressure-driven entry of radon-containing soil gas into the building. Following completion, indoor radon levels in the school will be monitored to determine the effectiveness of these radon-resistant new-construction techniques and HVAC overpressurization in limiting radon entry into the school.

  2. INDOOR RADON REDUCTION IN CRAWL-SPACE HOUSES: A REVIEW OF ALTERNATIVE APPROACHES

    EPA Science Inventory

    An analysis has been completed of the performance, mechanisms, and costs of alternative technologies for preventing radon entry into the living areas of houses having crawl-space foundations. Sub-membrane depressurization (SMD) is consistently the most effective technique, often ...

  3. 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.

  4. An Environmental Chemistry Experiment: The Determination of Radon Levels in Water.

    ERIC Educational Resources Information Center

    Welch, Lawrence E.; Mossman, Daniel M.

    1994-01-01

    Describes a radiation experiment developed to complement a new environmental chemistry laboratory curriculum. A scintillation counter is used to measure radon in water. The procedure relies on the fact that toluene will preferentially extract radon from water. Sample preparation is complete in less than 90 minutes. Because the level of…

  5. 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.

  6. RADON REDUCTION AND RADON RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK

    EPA Science Inventory

    The report covers three tasks related to indoor radon: (1) the demonstration of radon reduction techniques in 8 houses in each of two uniquely different radon prone areas of the State of New York; (2) the evaluation and repair of 14 radon mitigation systems in houses mitigated 4 ...

  7. Indoor inhalation dose estimates due to radon and thoron in some areas of South-Western Punjab, India.

    PubMed

    Kumar, Sanjeev; Singh, Surinder; Bajwa, Bikramjit Singh; Singh, Bhupinder; Sabharwal, Arvind D; Eappen, K P

    2012-08-01

    LR-115 (type II)-based radon-thoron discriminating twin-chamber dosemeters have been used for estimating radon ((222)Rn) and thoron ((220)Rn) concentrations in dwellings of south-western Punjab, India. The present study region has shown pronounced cases of cancer incidents in the public [Thakur, Rao, Rajwanshi, Parwana and Kumar (Epidemiological study of high cancer among rural agricultural community of Punjab in Northern India. Int J Environ Res Public Health 2008; 5(5):399-407) and Kumar et al. (Risk assessment for natural uranium in subsurface water of Punjab state, India. Hum Ecol Risk Assess 2011;17:381-93)]. Radon being a carcinogen has been monitored in some dwellings selected randomly in the study area. Results show that the values of radon ((222)Rn)  varied from 21 to 79 Bq m(-3), with a geometric mean of 45 Bq m(-3) [geometric standard deviation (GSD 1.39)], and those of thoron ((220)Rn)  from minimum detection level to 58 Bq m(-3) with a geometric mean of 19 Bq m(-3) (GSD 1.88). Bare card data are used for computing the progeny concentration by deriving the equilibrium factor (F) using a root finding method [Mayya, Eappen and Nambi (Methodology for mixed field inhalation dosimetry in monazite areas using a twin-cup dosemeter with three track detectors. Radiat Prot Dosim 1998;77(3):177-84)]. Inhalation doses have been calculated and compared using UNSCEAR equilibrium factors and by using the calculated F-values. The results show satisfactory comparison between the values.

  8. 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...

  9. Radon in outdoor air in Nevada

    SciTech Connect

    Price, J.G.; Rigby, J.G.; Christensen, L.

    1994-04-01

    Measurements of radon at 50 sites with varying geology indicate that outdoor air in Nevada is comparable to that measured nationwide by Hopper et al. The state-wide median of 15 Bq m{sup -3} (0.4 pCi L{sup -1}) is essentially the same as the nationwide median. The range is considerable: from 2.6-52 Bq m{sup -3} (0.07-1.40 pCi L{sup -1}). Variations in these measurements can generally be correlated with different concentrations of radon in soils and uranium and its progeny in rocks. Silica-rich igneous rocks (rhyolites and granites) appear to be the main sources of high levels of radon in outdoor air in Nevada. Concentrations of radon in outdoor air generally correlate with levels of radon in soil gas. Measurements taken from heights of 0.5, 1.0, and 2.0 m above the ground suggest that radon in outdoor air reflects the local geology throughout this range of heights. Towns for which >20% of the homes have indoor-air radon concentrations >48 Bq m{sup -3} (4 pCi L{sup -1}) generally have relatively high soil-gas radon, relatively high outdoor-air radon, or both. 16 refs., 4 figs., 1 tab.

  10. Radon in outdoor air in Nevada.

    PubMed

    Price, J G; Rigby, J G; Christensen, L; Hess, R; LaPointe, D D; Ramelli, A R; Desilets, M; Hopper, R D; Kluesner, T; Marshall, S

    1994-04-01

    Measurements of radon at 50 sites with varying geology indicate that outdoor air in Nevada is comparable to that measured nationwide by Hopper et al. (1991). The statewide median of 15 Bq m-3 (0.4 pCi L-1) is essentially the same as the nationwide median. The range is considerable: from 2.6-52 Bq m-3 (0.07-1.40 pCi L-1). Variations in these measurements can generally be correlated with different concentrations of radon in soils and uranium and its progeny in rocks. Silica-rich igneous rocks (rhyolites and granites) appear to be the main sources of high levels of radon in outdoor air in Nevada. Concentrations of radon in outdoor air generally correlate with levels of radon in soil gas. Measurements taken from heights of 0.5, 1.0, and 2.0 m above the ground suggest that radon in outdoor air reflects the local geology throughout this range of heights. Towns for which > 20% of the homes have indoor-air radon concentrations > 48 Bq m-3 (4 pCi L-1) generally have relatively high soil-gas radon, relatively high outdoor-air radon, or both.

  11. 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.

  12. Map showing radon potential of rocks and soils in Fairfax County, Virginia

    USGS Publications Warehouse

    Otton, James K.; Schumann, R. Randall; Owen, Douglass E.; Thurman, Nelson; Duval, Joseph S.

    1988-01-01

    Since 1984, indoor radon has gained national attention as a significant health hazard in the United States. Radon is a colorless, odorless, radioactive gas derived from uranium by radioactive decay. The U.S. Environmental Protection Agency (EPA) now projects that 5,000 to 20,000 lung-cancer deaths per year may be attributed to the long-term exposure to indoor radon and its radioactive decay products. Indoor radon has been previously recognized as a health hazard associated with uranium-bearing mill tailings or building materials, but it was not until December 1984 that some natural soils and rocks were found to be sources of indoor radon at levels comparable to those in uranium mines. It is now suspected that elevated indoor radon levels are far more widespread than initially though. The EPA considers 4 picoCuries of radon per liter of air (pCi/L) as the level (in a year-round measurement) at which actions ought to be taken to lower the concentration of indoor radon. All soils and rocks contain measurable amounts of uranium, which generate measurable amounts of radon. Certain soils and rocks, however, have a greater potential to cause indoor radon problems than others because (1) they have a higher uranium content and thus can generate higher levels of radon in soil gas (gas that occupies the pores of the soil), and (2) the permeability of the sol or rack is sufficiently high that radon-bearing soil gas can flow freely and move indoors through the foundation of the structure. This study was designed to demonstrate the correlation between the geologic environment and indoor radon levels and to demonstrate a method of assessment that could be used by other informed workers in areas of their interest. A parallel study by Gundersen and others (1988) of the radon potential of rocks and soils in Montgomery County, Md., used somewhat different methods of assessment because the data available for and assessment of Montgomery County differed.

  13. 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...

  14. 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...

  15. Managing Radon in Schools

    EPA Pesticide Factsheets

    EPA recommends testing all schools for radon. As part of an effective IAQ management program, schools can take simple steps to test for radon and reduce risks to occupants if high radon levels are found.

  16. Indoor Air Quality in Schools (IAQ): The Importance of Monitoring Carbon Dioxide Levels.

    ERIC Educational Resources Information Center

    Sundersingh, David; Bearg, David W.

    This article highlights indoor air quality and exposure to pollutants at school. Typical air pollutants within schools include environmental tobacco smoke, formaldehyde, volatile organic compounds, nitrogen oxides, carbon monoxide, carbon dioxide, allergens, pathogens, radon, pesticides, lead, and dust. Inadequate ventilation, inefficient…

  17. Cancer risks from exposure to radon in homes.

    PubMed Central

    Axelson, O

    1995-01-01

    Exposure to radon and its decay products in mines is a well recognized risk of lung cancer in miners. A large number of epidemiologic studies from various countries are quite consistent in this respect even it the magnitude of the risk differs according to exposure levels. Indoor radon became a concern in the 1970s and about a dozen studies have been conducted since 1979, mainly of the case-control design. From first being of a simple pilot character, the designs have become increasingly sophisticated, especially with regard to exposure assessment. Crude exposure estimates based on type of house, building material and geological features have been supplemented or replaced by quite extensive measurements. Still, exposure assessment remains a difficult and uncertain issue in these studies, most of which indicate a lung cancer risk from indoor radon. Also a recent large scale study has confirmed a lung cancer risk from indoor radon. More recently there are also some studies, mainly of the correlation type, suggesting other cancers also to be related to indoor radon, especially leukemia, kidney cancer, and malignant melanoma, and some other cancers as well. The data are less consistent and much more uncertain than for indoor radon and lung cancer, however; and there is no clear support from studies of miners in this respect. PMID:7614945

  18. Radon concentration levels in ground water from Toluca, Mexico.

    PubMed

    Olguin, M T; Segovia, N; Tamez, E; Alcántara, M; Bulbulian, S

    1993-03-25

    Concentration levels of 222Rn have been analysed in water samples from deep wells of the aquifers around the City of Toluca, Mexico. The 222Rn source is the decay of 226Ra within the solid matrix of the aquifer. With a half life of 1600 years the 226Ra continuously releases 222Rn to the pores, from which it diffuses into the main body of water. This paper describes the methods used for sampling and measuring solubilized and 226Ra-supported 222Rn in the water samples, in order to evaluate possible health hazards due to the presence of radon in the drinking water supplies. The relationship of 222Rn with the hydrogeologic characteristics of the zone is also described. The analytical method involves laboratory extraction of 222Rn into toluene. Alpha disintegrations of 222Rn and contributions from short-lived daughters are counted by the liquid scintillation technique. The system was calibrated using a 226Ra standard solution. Results up to 11.3 Bq/l of 222Rn were obtained in the water samples.

  19. STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND PROGENY IN THE INDOOR ENVIRONMENT OF YAMUNA AND TONS VALLEYS OF GARHWAL HIMALAYA.

    PubMed

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Prasad, Ganesh; Mishra, Rosaline; Ramola, R C

    2016-10-01

    Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y(-1) with an average of 1.8 mSv y(-1) The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail.

  20. 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)

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

    PubMed

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

    2015-12-01

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

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

    NASA Astrophysics Data System (ADS)

    Kourtidis, Konstantinos; Georgoulias, Aristeidis; Tsirliganis, Nestor

    2016-04-01

    Extensive measurements of Rn-222 in the town of Xanthi in N Greece show that the part of the town overlying granite deposits and the outcrop of a uranium ore has exceptionally high indoor radon levels, with monthly means up to 1500 Bq m-3. A large number of houses (40%) in this part of the town exhibit radon levels above 200 Bq m-3 while 11% of the houses had radon levels above 400 Bq/m3. Substantial interannual variability as well as the highest in Europe winter/summer ratios (up to 12) were observed in this part of the town, which consist of traditional stone masonry buildings of the late 19th- early 20th century. Measurements of U-238 and Th-232 content of building materials from these houses as well as radionuclide measurements in different floors show that the high levels of indoor radon measured in these buildings are not due to high radon emanation rates from the building materials themselves but rather due to high radon flux from the soil because of the underlying geology, high radon penetration rates into the buildings from underground due to the lack of solid concrete foundations in these buildings, or a combination thereof. From the meteorological variables studied, highest correlation with indoor Rn-222 was found with temperature (r2=0.65). An indoor radon prognostic regression model using temperature, pressure and precipitation as input was developed, that reproduced indoor radon with r2=0.69. Hence, meteorology is the main driving factor of indoor radon, with temperature being the most important determinant. Preliminary flux measurements indicate that the soil-atmosphere Rn-222 flux should be in the range 150-250 Bq m-2 hr-1, which is in the upper 10% of flux values for Europe.

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

    PubMed

    Linzmaier, Diana; Röttger, Annette

    2013-11-01

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

  4. Radon exhalation from building materials for decorative use.

    PubMed

    Chen, Jing; Rahman, Naureen M; Abu Atiya, Ibrahim

    2010-04-01

    Long-term exposure to radon increases the risk of developing lung cancer. There is considerable public concern about radon exhalation from building materials and the contribution to indoor radon levels. To address this concern, radon exhalation rates were determined for 53 different samples of drywall, tile and granite available on the Canadian market for interior home decoration. The radon exhalation rates ranged from non-detectable to 312 Bq m(-2) d(-1). Slate tiles and granite slabs had relatively higher radon exhalation rates than other decorative materials, such as ceramic or porcelain tiles. The average radon exhalation rates were 30 Bq m(-2) d(-1) for slate tiles and 42 Bq m(-2) d(-1) for granite slabs of various types and origins. Analysis showed that even if an entire floor was covered with a material having a radon exhalation rate of 300 Bq m(-2) d(-1), it would contribute only 18 Bq m(-3) to a tightly sealed house with an air exchange rate of 0.3 per hour. Generally speaking, building materials used in home decoration make no significant contribution to indoor radon for a house with adequate air exchange.

  5. Children's Physical Activity Levels during Indoor Recess Dance Videos

    ERIC Educational Resources Information Center

    Erwin, Heather; Koufoudakis, Ryann; Beighle, Aaron

    2013-01-01

    Background: Children's physical activity (PA) levels remain low, and schools are being asked to assume a leadership role in PA promotion. Research suggests outdoor recess contributes to children's overall PA levels. However, similar research is not available for indoor recess, which occurs frequently due to a variety of factors. The purpose of…

  6. 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

  7. Radon Levels Measured at a Touristic Thermal Spa Resort in Montagu (South Africa) and Associated Effective Doses.

    PubMed

    Botha, R; Newman, R T; Maleka, P P

    2016-09-01

    Radon activity concentrations (in water and in air) were measured at 13 selected locations at the Avalon Springs thermal spa resort in Montagu (Western Cape, South Africa) to estimate the associated effective dose received by employees and visitors. A RAD-7 detector (DURRIDGE), based on alpha spectrometry, and electret detectors (E-PERM®Radelec) were used for these radon measurements. The primary source of radon was natural thermal waters from the hot spring, which were pumped to various locations on the resort, and consequently a range of radon in-water analyses were performed. Radon in-water activity concentration as a function of time (short term and long term measurements) and spatial distributions (different bathing pools, etc.) were studied. The mean radon in-water activity concentrations were found to be 205 ± 6 Bq L (source), 112 ± 5 Bq L (outdoor pool) and 79 ± 4 Bq L (indoor pool). Radon in-air activity concentrations were found to range between 33 ± 4 Bq m (at the outside bar) to 523 ± 26 Bq m (building enclosing the hot spring's source). The most significant potential radiation exposure identified is that due to inhalation of air rich in radon and its progeny by the resort employees. The annual occupational effective dose due to the inhalation of radon progeny ranges from 0.16 ± 0.01 mSv to 0.40 ± 0.02 mSv. For the water samples collected, the Ra in-water activity concentrations from samples collected were below the lower detection limit (~0.7 Bq L) of the γ-ray detector system used. No significant radiological health risk can be associated with radon and progeny from the hot spring at the Avalon Springs resort.

  8. Preliminary assessment of radon potential of the Pacific coast states

    SciTech Connect

    Otton, J.K. )

    1993-04-01

    The US Geological Survey has recently released preliminary assessments of the radon potential in Washington, Oregon, and California. These assessments, funded by the Environmental Protection Agency, are based on geology, soils, aeroradiometric data, indoor radon data, and housing characteristics. Coastal mountain areas with low-uranium basaltic rocks and high soil moisture, and drier inland areas of low-uranium basaltic rocks in the northern part of the three-stage area have low round potential (<10 percent of homes with >4 pCi/L). Areas with highly permeable, uraniferous glacial outwash deposits in central and northeastern Washington; local areas with uraniferous marine shales in southern and south-central California; areas of granites, acidic volcanic rocks and alluvium derived from then in southeastern Oregon and central California; and steep soils developed on volcanic rocks in the Columbia River Gorge all have moderate (10-25 percent of homes with >4 pCi/L) radon potential. Extreme levels of indoor radon are possible in the northern Spokane, Wash. suburbs where homes may be sited on uranium occurrences. the radon potential of Mojave-Desert areas with high-uranium soils and rocks seems to be lowered by low radon entry rates, probably caused by slab-on-grade construction, use of evaporative coolers, and lifestyle factors. With the uranium-rich soils and rocks present, however, high indoor radon levels are possible where unusual housing conditions are present.

  9. The use of volunteer radon measurements for radon mapping purposes: an examination of sampling bias issues.

    PubMed

    Burke, Orlaith; Murphy, Patrick

    2011-09-01

    National and regional radon surveys are used in many nations to produce maps detailing the spatial variation of indoor radon concentrations. National surveys which are designed to be representative use either a geographically-weighted or a population-weighted sampling scheme. Additionally, many countries collect a large number of data on indoor radon concentrations from volunteers who have chosen to have the indoor radon concentration measured in their own dwellings. This work examines the representativeness of volunteer-based samples in radon measurement and explores the effect of potential volunteer bias on radon mapping results. We also investigate the influence that media attention has on volunteer sampling of indoor radon concentrations. The result of our work indicates that volunteer measurements are biased due to over-sampling of high radon areas. Consequently such volunteer radon measurements should not be used for radon mapping purposes.

  10. Impact of intentionally introduced sources on indoor VOC levels

    SciTech Connect

    Davis, C.S.; Otson, R.

    1997-12-31

    The concentrations of 33 target volatile organic compounds (VOC) were measured in outdoor air and in indoor air before and after the introduction of dry-cleaned clothes, and consumer products into two suburban homes. Emissions from the household products (air fresheners, furniture polishes, mothballs, and dry-cleaned clothes), showering, and two paints were analyzed to obtain source profiles. There were measurable increases in the 24 h average concentrations for 10 compounds in one house and 8 compounds in the second house after introduction of the sources. A contribution by showering to indoor VOC was not evident although the impact of the other sources and outdoor air could be discerned, based on results for the major constituents of source emissions. Also, contributions by paints, applied three to six weeks prior to the monitoring, to indoor VOC concentrations were evident. The pattern of concentrations indicated that sink effects need to be considered in explaining the indoor concentrations that result when sources are introduced into homes. Quantitative estimates of the relative contributions of the sources to indoor VOC levels were not feasible through the use of chemical mass balance since the number of tracer species detected (up to 6) and that could be used for source apportionment was similar to the number of sources to be apportioned (up to 7).

  11. CONTRIBUTION TO INDOOR OZONE LEVELS OF AN OZONE GENERATOR

    EPA Science Inventory

    This report gives results of a study of a commonly used commercially available ozone generator, undertaken to determine its impact on indoor ozone levels. xperiment were conducted in a typical mechanically ventilated office and in a test house. he generated ozone and the in-room ...

  12. Follow-up annual alpha-track monitoring in 40 eastern Pennsylvania houses with indoor radon reduction systems (December 1988-December 1989). Final report, December 1988-June 1990

    SciTech Connect

    Scott, A.G.; Robertson, A.

    1990-11-01

    The report gives results of 12-month-long alpha-track detector (ATD) measurements of indoor radon concentrations, between December 1988 and December 1989 in th living areas of 38 of 40 houses where radon reduction techniques has been installed 2-4 years earlier in a previous EPA project. The techniques, installed between June 1985 and June 1987, generally involved active soil depressurization. In the 28 houses in which the mitigation system operated the entire year, the annual average was < 2 pCi/L in 13, and < 4 pCi/L in 22. The residual radon in many houses is due largely to re-entrainment of ASD exhaust. Comparison of these annual ATD results with quarterly results from the past three winters shows that 22 of the 28 houses had annual measurements within 1 pCi/L of the winter-quarter result. There had been no significant degradation in system performance, except where the mitigation fans failed or where the owner had turned off the system. Six of 34 ASD fans have failed to date.

  13. Testing of indoor radon reduction techniques in central Ohio houses: Phase 2 (Winter 1988-1989). Final report, September 1988-May 1989

    SciTech Connect

    Findlay, W.O.; Robertson, A.; Scott, A.G.

    1990-05-01

    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. The slab-on-grade tests indicated that, when there is a good layer of aggregate under the slab, the sub-slab ventilation (SSV) mitigation technique, with only one or two suction pipes, can generally reduce indoor concentrations below 2 pCi/L (86 to 99% reduction). These reductions can be achieved even when: there are forced-air supply ducts under the slab; the slab is large (up to 2600 sq ft); and the foundation walls are hollow block. Operating the SSV system in suction always gave greater reductions than did operating in pressure. The crawl-space tests demonstrated that depressurizing under a plastic liner over the crawl-space floor was able to reduce living-area radon concentrations below 2 pCi/L (81 to 96% reduction). The performance of such sub-liner depressurization gave better reductions than did crawl-space ventilation (blowing air into, or out of, the crawl space). Completely covering the crawl-space floor with plastic sheeting was not always necessary to get adequate performance.

  14. 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.

  15. Dependence of radon levels in Postojna Cave on outside air temperature

    NASA Astrophysics Data System (ADS)

    Gregorič, A.; Zidanšek, A.; Vaupotič, J.

    2011-05-01

    Postojna Cave is the largest of 21 show caves in Slovenia. The radon concentration there was measured continuously in the Great Mountain hall from July 2005 to October 2009 and ranged from about 200 Bq m-3 in winter to about 3 kBq m-3 in summer. The observed seasonal pattern of radon concentration is governed by air movement due to the difference in external and internal air densities, controlled mainly by air temperature. The cave behaves as a large chimney and in the cold period, the warmer cave air is released vertically through cracks and fissures to the colder outside atmosphere, enabling the inflow of fresh air with low radon levels. In summer the ventilation is minimal or reversed and the air flows from the higher to the lower openings of the cave. Our calculations have shown that the effect of the difference between outside and cave air temperatures on radon concentration is delayed for four days, presumably because of the distance of the measurement point from the lower entrance (ca. 2 km). A model developed for predicting radon concentration on the basis of outside air temperature has been checked and found to be successful.

  16. Radon and thoron levels, their spatial and seasonal variations in adobe dwellings - a case study at the great Hungarian plain.

    PubMed

    Szabó, Zsuzsanna; Jordan, Gyozo; Szabó, Csaba; Horváth, Ákos; Holm, Óskar; Kocsy, Gábor; Csige, István; Szabó, Péter; Homoki, Zsolt

    2014-06-01

    Radon and thoron isotopes are responsible for approximately half of the average annual effective dose to humans. Although the half-life of thoron is short, it can potentially enter indoor air from adobe walls. Adobe was a traditional construction material in the Great Hungarian Plain. Its major raw materials are the alluvial sediments of the area. Here, seasonal radon and thoron activity concentrations were measured in 53 adobe dwellings in 7 settlements by pairs of etched track detectors. The results show that the annual average radon and thoron activity concentrations are elevated in these dwellings and that the proportions with values higher than 300 Bq m(-3) are 14-17 and 29-32% for radon and thoron, respectively. The calculated radon inhalation dose is significantly higher than the world average value, exceeding 10 mSv y(-1) in 7% of the dwellings of this study. Thoron also can be a significant contributor to the inhalation dose with about 30% in the total inhalation dose. The changes of weather conditions seem to be more relevant in the variation of measurement results than the differences in the local sedimentary geology. Still, the highest values were detected on clay. Through the year, radon follows the average temperature changes and is affected by the ventilation, whereas thoron rather seems to follow the amount of precipitation.

  17. Radiological risk assessment of environmental radon

    SciTech Connect

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

    2013-11-27

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

  18. Radiological risk assessment of environmental radon

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

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

  19. Radon and climatic multiparameter analysis: A one-year study on radon dynamics in a house

    SciTech Connect

    Genrich, V.

    1995-12-31

    Radon-reduction in private and public buildings is a current issue. Research has opened our eyes for the enormous fluctuations of the indoor radon level over longer observation periods. For generalizing the behavior radon in a building, care must be taken that the observation period is long enough, to mediate the pronounced climatic changes in the course of a year. The author has started a one-year observations, precisely logging up the radon level in a single family home. Six portable multiparameter-monitors, each equipped with a 0.6 liter PIC-detector (PIC = pulse ionization chamber), have been installed at different locations within the building and outdoors (incl. two soil-gas probes). Besides the radon concentration, in the same instruments the following parameters are logged cotinuously: relative humidity, differential pressure between basement and sub-slab area, soil impendance (indication water saturation) and wind speed on the roof. In the basement, the radon concentration varies between 61 Bq/m{sup 3} and 5408 Bq/m{sup 3} (mean: 1092 Bq/m{sup 3}.) By analyzing these records, the time sequence of the radon concentration can be characterized as a {open_quotes}mixture{close_quotes} of (periodic) circadian variations overlayed with (aperiodic) seasonal fluctuations. In this building, it turns out, that the pressure difference across the base plate is an important factor for radon entry as well as ventilation rate. It can be shown, that the pressure is closely related to the indoor-outdoor temperature difference. This relation was found to be non-linear. Other factors are attributed to the activities of the inhabitants. The paper points out correlations between radon and different climatic parameters mainly by using scatterplots and classical regression methods.

  20. A Systematic Review of Radon Investigations Related to Public Exposure in Iran

    PubMed Central

    Pirsaheb, Meghdad; Najafi, Farid; Khosravi, Touba; Hemati, Lida

    2013-01-01

    Background The main sources of radiation exposure of all living organisms including humans are natural. In fact, radon and its decay products are the cause of 50% of the total dose that is derived from natural sources. Because of the significant health hazards of radon gas, its levels are widely monitored throughout the world. Accordingly, considerable researches have also been carried out in Iran. Objectives The aim of this research is a systematic review of the most recent studies associated with evaluation of radon gas levels in Iran. The main emphasis of this study was on public exposure to radon gas. Materials and Methods The most important route of exposure to such radiation is indoor places. In this investigation measurement of radon in water resources, tap water, indoor places and exhalation of radon from building material, the major sources of indoor radon gas emission, were considered. Results Significantly high levels of radon gas were found mostly in water and residenvial buildings. Conclusions It conclusion with regard to the study of building materials, granite stone and adobe coverings cannot be recommended for construction purposes. PMID:24719680

  1. Radon in soil gas and its relationship with some major faults of SW England.

    PubMed

    Varley, N R; Flowers, A G

    1993-09-01

    The south-west of England was designated by the National Radiological Protection Board (NRPB) as the first 'Radon Affected Area', as over 1% of the housing stock is estimated to have an indoor radon concentration in excess of the 200 Bq m(-3) Action Level. The situation is even worse for houses situated above uraniferous granite intrusions, where over 30% are thought to be above the Action Level.The aim of this study is to investigate the relationship between the level of radon in soil gas and the local geology. Particularly high radon levels were measured along major fault zones. This could be explained by: increased rate of migration of the radon due to the permeable fault, the presence of radium or radon-bearing ground water within the fault, or secondary uranium mineralisation. Seasonal variations are also considered.

  2. Transport studies of radon in limestone underlying houses

    SciTech Connect

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

    1990-01-01

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

  3. Measuring radioactive noble gases by absorption in polycarbonates and other organics: From radon indoors to nuclear safety

    NASA Astrophysics Data System (ADS)

    Pressyanov, Dobromir S.

    2013-07-01

    The report summarizes recent research and practice of using materials with high absorption ability to noble gases to measure their radioactive isotopes. Most of the studies employ bisphenol-A based polycarbonates, because of their remarkably high absorption ability to noble gases. This is the material of which commercial CDs/DVDs are made and they may serve as serendipitous, already available in dwellings, radon and thoron detectors. We present the essence of the gathered experimental evidence that the CD/DVD method can successfully address some long-lasted problems in radon dosimetry: The first is making sufficiently precise retrospective 222Rn dosimetry for the purposes of epidemiological studies and risk estimation. The second is rapid identification of buildings with radon problem. We demonstrate how this can be used to develop an integrated approach to the radon problem. Within this approach detection, diagnostic and mitigation are considered as an unified whole, and the interval between the decision to provide disks for analysis and the complete mitigation of the building, if radon problem is identified, is short. Besides radon and thoron, bisphenol-A based polycarbonates were successfully used to measure 85Kr and 133Xe for the purposes of the effluents control and nuclear safety of nuclear installations. The perspectives to employ other organic materials in which noble gases are highly soluble for measurement of their radioactive isotopes are also discussed.

  4. A comparison of winter short-term and annual average radon measurements in basements of a radon-prone region and evaluation of further radon testing indicators.

    PubMed

    Barros, Nirmalla G; Steck, Daniel J; Field, R William

    2014-05-01

    The primary objective of this study was to investigate the temporal variability between basement winter short-term (7 to 10 d) and basement annual radon measurements. Other objectives were to test the short-term measurement's diagnostic performance at two reference levels and to evaluate its ability to predict annual average basement radon concentrations. Electret ion chamber (short-term) and alpha track (annual) radon measurements were obtained by trained personnel in Iowa residences. Overall, the geometric mean of the short-term radon concentrations (199 Bq m) was slightly greater than the geometric mean of the annual radon concentrations (181 Bq m). Short-term tests correctly predicted annual radon concentrations to be above the 148 Bq m action level 88% of the time and above a 74 Bq m level 98% of the time. The short-term and annual radon concentrations were strongly correlated (r = 0.87, p < 0.0001). The foundation wall material of the basement was the only significant factor to have an impact on the absolute difference between the short-term and annual measurements. The findings from this study provide evidence of a substantially lower likelihood of obtaining a false negative result from a single short-term test in a region with high indoor radon potential when the reference level is lowered to 74 Bq m.

  5. 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...

  6. Radon (222Rn) level variations on a regional scale: influence of the basement trace element (U, Th) geochemistry on radon exhalation rates.

    PubMed

    Ielsch, G; Thiéblemont, D; Labed, V; Richon, P; Tymen, G; Ferry, C; Robé, M C; Baubron, J C; Béchennec, F

    2001-01-01

    The approach proposed in this study provides insight into the influence of the basement geochemistry on the spatial distribution of radon (222Rn) levels both at the soil/atmosphere interface and in the atmosphere. We combine different types of in situ radon measurements and a geochemical classification of the lithologies, based on 1/50,000 geological maps, and on their trace element (U, Th) contents. The advantages of this approach are validated by a survey of a stable basement area of Hercynian age, located in South Brittany (western France) and characterized by metamorphic rocks and granitoids displaying a wide range of uranium contents. The radon source-term of the lithologies, their uranium content, is most likely to be the primary parameter which controls the radon concentrations in the outdoor environment. Indeed, the highest radon levels (> or = 100 Bq m-3 in the atmosphere, > or = 100 mBq m-2 s-1 at the surface of the soil) are mostly observed on lithologies whose mean uranium content can exceed 8 ppm and which correspond to peraluminous leucogranites or metagranitoids derived from uraniferous granitoids.

  7. Radon reduction and radon-resistant construction demonstrations in New York. Volume 1. Technical report. Final report, March 1987-February 1991

    SciTech Connect

    Nitschke, I.; Clarkin, M.; Clark, W.; Hough, R.E.

    1993-03-01

    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 foundation penetrations in the basement effectively reduced the radon concentration, although not below 4 pCi/L, and that sealing aids the effectiveness of an active depressurization system. Active depressurization systems were usually successful in achieving 4 pCi/L. The footing drain, sub-slab, and basement walls were all successfully depressurized using a standard technique after grab samples or radon 'sniffing' techniques were used to identify the radon entry sources. Basement pressurization also effectively reduced the radon level below the EPA guideline at one site. Water aeration systems effectively mitigated radon from residential water supplies, although the system tested was large and noisy. Activated charcoal filters adsorbed the radon in water, but eventually became an unacceptable source of gamma radiation. The inspection of houses where radon mitigation systems were installed in 1984 revealed that new systems and techniques, such as in-line centrifugal fans, were generally superior to the earlier methods using axial computer-type fans.

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

    PubMed

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

    2005-01-01

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

  9. 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.

  10. 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.

  11. Radon concentration of waters in Greece and Cyprus

    NASA Astrophysics Data System (ADS)

    Nikolopoulos, D.; Vogiannis, E.; Louizi, A.

    2009-04-01

    Radon (222Rn) is a radioactive gas generated by the decay of the naturally occurring 238U series. It is considered very important from radiological point of view, since it is the most significant natural source of human radiation exposure (approximately 50% from all natural sources). Radon is present in soil, rocks, building materials and waters. Through diffusion and convection, radon migrates and emanates to the atmosphere. Outdoors, radon concentrates at low levels (in the order of 10 Bq/m3). However indoors, radon accumulates significantly. It is trivial to observe indoor environments with high radon levels (in the order of 400 Bq/m3 or higher). Radon accumulation indoors, depends on the composition of the underlying soil and rock formation, on building materials, meteorological parameters, ventilation, heating and water use. Although soil and building materials are the most significant radon sources, there have been reported elevated radon concentrations in building structures due to entering water. It is the radon concentrations in the entering water, the volume and the way of water usage, separated or in combination, that result in large amounts of radon in indoor air. Moreover, radon is a factor of stomach radiation burden due to water consumption. This burden is estimated by measurements of radon concentrations in waters. Due to the health impact of radon exposure, the reporting team continuously measures radon. This work focused on the radon concentrations exposure due to water consumption and use in Greece and Cyprus. Various locations in Greece and Cyprus were accessed taking into consideration existing natural radioactivity data (mainly radon in water), however under the restriction of the capability of movement. Radon in water was measured by Alpha Guard (Genitron Ltd) via a special unit (Aqua Kit). This unit consists of a vessel used for forced degassing of radon diluted in water samples, a security vessel used for water drop deposition. Vessels and

  12. Homogenity of geological units with respect to the radon risk in the Walloon region of Belgium.

    PubMed

    Tondeur, François; Cinelli, Giorgia; Dehandschutter, Boris

    2014-10-01

    In the process of mapping indoor radon risk, an important step is to define geological units well-correlated with indoor radon. The present paper examines this question for the Walloon region of Belgium, using a database of more than 18,000 indoor radon measurements. With a few exceptions like the Carboniferous (to be divided into Tournaisian, Visean and Namurian-Westphalian) and the Tertiary (in which all Series may be treated together), the Series/Epoch stratigraphic level is found to be the most appropriate geological unit to classify the radon risk. A further division according to the geological massif or region is necessary to define units with a reasonable uniformity of the radon risk. In particular, Paleozoic series from Cambrian to Devonian show strong differences between different massifs. Local hot-spots are also observed in the Brabant massif. Finally, 35 geological units are defined according to their radon risk, 6 of which still present a clear weak homogeneity. In the case of 4 of these units (Jurassic, Middle Devonian of Condroz and of Fagne-Famenne, Ordovician of the Stavelot massif) homogeneity is moderate, but the data are strongly inhomogeneous for Visean in Condroz and in the Brabant massif. The 35 geological units are used in an ANOVA analysis, to evaluate the part of indoor radon variability which can be attributed to geology. The result (15.4-17.7%) agrees with the values observed in the UK.

  13. A COMPARISON OF WINTER SHORT-TERM AND ANNUAL AVERAGE RADON MEASUREMENTS IN BASEMENTS OF A RADON-PRONE REGION AND EVALUATION OF FURTHER RADON TESTING INDICATORS

    PubMed Central

    Barros, Nirmalla G.; Steck, Daniel J.; Field, R. William

    2014-01-01

    The primary objective of this study was to investigate the temporal variability between basement winter short-term (7 to 10 days) and basement annual radon measurements. Other objectives were to test the short-term measurement’s diagnostic performance at two reference levels and to evaluate its ability to predict annual average basement radon concentrations. Electret ion chamber (short-term) and alpha track (annual) radon measurements were obtained by trained personnel in Iowa residences. Overall, the geometric mean of the short-term radon concentrations (199 Bq m−3) was slightly greater than the geometric mean of the annual radon concentrations (181 Bq m−3). Short-term tests incorrectly predicted that the basement annual radon concentrations would be below 148 Bq m−3 12% of the time and 2% of the time at 74 Bq m−3. The short-term and annual radon concentrations were strongly correlated (r=0.87, p<0.0001). The foundation wall material of the basement was the only significant factor to have an impact on the absolute difference between the short-term and annual measurements. The findings from this study provide evidence of a substantially lower likelihood of obtaining a false negative result from a single short-term test in a region with high indoor radon potential when the reference level is lowered to 74 Bq m−3. PMID:24670901

  14. Inhalation dose due to radon, thoron, and progenies in dwellings of a hill station.

    PubMed

    Sivakumar, R

    2017-02-01

    The general public spends a major portion of their time in an indoor environment and hence receives a considerable amount of radiation. Knowledge about indoor radiation is important in order to arrive at the actual effective dose received by residents. The indoor radon, thoron, and progeny concentrations observed in the present study were found to vary with seasons of a given year. The highest and lowest indoor average radon, thoron, and progeny levels were observed during winter and summer seasons, respectively. The concentrations of indoor radon, thoron, and progenies were found to vary with the type of houses. The highest (222)Rn, (220)Rn, and progeny concentrations were observed in mud houses and the lowest values were recorded in wooden houses. The indoor (222)Rn concentration correlated well with concentration of its grandparent (238)U in underlying soil with a correlation coefficient of 0.87. The correlation between indoor (220)Rn and (232)Th in the underlying soil was found to be 0.64. The estimated effective doses received by the general public in the present study due to indoor radon and thoron were 1.49 ± 0.49 and 1.30 ± 0.53 mSv/year, respectively. The annual effective doses due to radon and thoron progenies were estimated as 0.76 ± 0.27 and 0.47 ± 0.23 mSv/year, respectively. The contributions from (222)Rn, (220)Rn, and corresponding progenies to the annual effective doses received were 37, 32, 19, and 12%, respectively. The general public living in the study area receives an inhalation dose of 4.02 mSv/year due to indoor radon, thoron, and progenies, which were found to be less than the action limit of ICRP 2009.

  15. 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.

  16. Indoor Air Pollution: An Energy Management Problem?

    ERIC Educational Resources Information Center

    Cousins, David M.; Kulba, John W.

    1987-01-01

    Energy conservation measures have led to airtight buildings and reduced levels of ventilation resulting in indoor air pollution. Five kinds of contaminants--tobacco smoke, combustion products, microorganisms, organic compounds, and radon--are described, their hazards considered, and countermeasures outlined. (MLF)

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

    USGS Publications Warehouse

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

    1988-01-01

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

  18. A Look at the Grouping Effect on Population-level Risk Assessment of Radon-Induced Lung Cancer

    PubMed Central

    Chen, Jing; Moir, Deborah

    2013-01-01

    On the basis of considerable knowledge gained by studying health effects in uranium and other underground miners who worked in radon-rich environments, radon exposure has been identified as a cause of lung cancer. Recent pooled analyses of residential studies have shown that radon poses a similar risk of causing lung cancer in the general public when exposure occurs at generally lower levels found in homes. With the increasing accessibility of statistical data via the internet, people are performing their own analyses and asking why, in some cases, the lung cancer occurrence at the community level does not correlate to the radon levels. This study uses statistical data available to the general public from official websites and performs simple analyses. The results clearly show the difficulty in linking observed lung cancer incidence rates at the provincial/territorial level, with possible cause, such as smoking or radon exposure. Even the effect of smoking, a well-documented cause of lung cancer, can be overlooked or misinterpreted if the data being investigated is too general (i.e., summary data at population level) or is influenced by other factors. These difficulties with simple comparisons are one of the main reasons that epidemiological studies of lung cancer incidence and radon exposure requires the use of cohorts or case controls at the individual level as opposed to the more easily performed ecological studies at the population level. PMID:24171868

  19. Children's Exposure to Radon in Nursery and Primary Schools.

    PubMed

    Branco, Pedro T B S; Nunes, Rafael A O; Alvim-Ferraz, Maria C M; Martins, Fernando G; Sousa, Sofia I V

    2016-03-30

    The literature proves an evident association between indoor radon exposure and lung cancer, even at low doses. This study brings a new approach to the study of children's exposure to radon by aiming to evaluate exposure to indoor radon concentrations in nursery and primary schools from two districts in Portugal (Porto and Bragança), considering different influencing factors (occupation patterns, classroom floor level, year of the buildings' construction and soil composition of the building site), as well as the comparison with IAQ standard values for health protection. Fifteen nursery and primary schools in the Porto and Bragança districts were considered: five nursery schools for infants and twelve for pre-schoolers (seven different buildings), as well as eight primary schools. Radon measurements were performed continuously. The measured concentrations depended on the building occupation, classroom floor level and year of the buildings' construction. Although they were in general within the Portuguese legislation for IAQ, exceedances to international standards were found. These results point out the need of assessing indoor radon concentrations not only in primary schools, but also in nursery schools, never performed in Portugal before this study. It is important to extend the study to other microenvironments like homes, and in time to estimate the annual effective dose and to assess lifetime health risks.

  20. Radon exposures in a Jerusalem public school.

    PubMed Central

    Richter, E D; Neeman, E; Fischer, I; Berdugo, M; Westin, J B; Kleinstern, J; Margaliot, M

    1997-01-01

    In December 1995, ambient radon levels exceeding 10,000 Bq/m3 were measured in a basement shelter workroom of a multilevel East Talpiot, Jerusalem, public elementary school (six grades, 600 students). The measurements were taken after cancers (breast and multiple myeloma) were diagnosed in two workers who spent their workdays in basement rooms. The school was located on a hill that geologic maps show to be rich in phosphate deposits, which are a recognized source for radon gas and its daughter products. Levels exceeding 1000,000 Bq/m3 were measured at the mouth of a pipe in the basement shelter workroom, the major point of radon entry. The school was closed and charcoal and electret ion chamber detectors were used to carry out repeated 5-day measurements in all rooms in the multilevel building over a period of several months. Radon concentrations were generally higher in rooms in the four levels of the building that were below ground level. There were some ground-level rooms in the building in which levels reached up to 1300 Bq/m3. In rooms above ground level, however, peak levels did not exceed 300 Bq/m3. Exposure control based on sealing and positive pressure ventilation was inadequate. These findings suggested that radon diffused from highly contaminated basement and ground-floor rooms to other areas of the building and that sealing off the source may have led to reaccumulation of radon beneath the building. Later, subslab venting of below-ground radon pockets to the outside air was followed by more sustained reductions in indoor radon levels to levels below 75 Bq/m3. Even so, radon accumulated in certain rooms when the building was closed. This sentinel episode called attention to the need for a national radon policy requiring threshold exposure levels for response and control. A uniform nationwide standard for school buildings below 75 Bq/m3 level was suggested after considering prudent avoidance, the controversies over risk assessment of prolonged low-level

  1. Characterizing the occurrence, sources, and variability of radon in Pacific Northwest homes.

    PubMed

    Turk, B H; Prill, R J; Grimsrud, D T; Moed, B A; Sextro, R G

    1990-04-01

    A compilation of data from earlier studies of 172 homes in the Pacific Northwest indicated that approximately 65 percent of the 46 homes tested in the Spokane River Valley/Rathdrum Prairie region of eastern Washington/northern Idaho had heating season indoor radon (222Rn) concentrations above the U. S. EPA guideline of 148 Bq m-3 (4 pCi L-1). A subset of 35 homes was selected for additional study. The primary source of indoor radon in the Spokane River Valley/Rathdrum Prairie was pressure-driven flow of soil gas containing moderate radon concentrations (geometric mean concentration of 16,000 Bq m-3) from the highly permeable soils (geometric mean permeability of 5 x 10(-11) m2) surrounding the house substructures. Estimated soil gas entry rates ranged from 0.4 to 39 m3h-1 and 1 percent to 21 percent of total building air infiltration. Radon from other sources, including domestic water supplies and building materials was negligible. In high radon homes, winter indoor levels averaged 13 times higher than summer concentrations, while in low radon homes winter levels averaged only 2.5 times higher. Short-term variations in indoor radon were observed to be dependent upon indoor-outdoor temperature differences, wind speed, and operation of forced-air furnace fans. Forced-air furnace operation, along with leaky return ducts and plenums, and openings between the substructure and upper floors enhanced mixing of radon-laden substructure air throughout the rest of the building.

  2. Preliminary study on the variation of radon-222 inside greenhouse of Shouguang county, China.

    PubMed

    Li, Xiaohong; Xu, Xianqin; Li, Wanwei; Wang, Fei; Hai, Chunxu

    2016-03-01

    Studies on radon have become the focus of indoor radiation. In this study, we chose greenhouse to be the study field, the research aims to: (1) explore the diurnal variation of radon concentration inside greenhouse in Shouguang county, China; (2) pre-analyze the relationship between radon concentration, temperature and relative humidity, and shed light on the radon behavior characteristic inside greenhouse; (3) verify the feasibility of calculating radon radiation dose by using short-period detected radon concentrations in typical months in Shouguang county. The following conclusions were drawn. Firstly, the average radon levels in typical months in Shouguang county are all much higher than that in ordinary dwellings in China, diurnal and seasonal variations in radon levels are observed inside greenhouse. Secondly, temperature and relative humidity may play a role indirectly through affecting soil moisture and other factors. The mechanism need to be further studied. Thirdly, radon concentrations detected in typical months are still useful in preliminary estimation of radon radiation dose for vegetable-plant farmers in Shouguang county.

  3. Assessment of the multimedia mitigation of radon in New York.

    PubMed

    Kitto, Michael E

    2007-05-01

    Although not yet implemented, the 1996 amendments to the Safe Drinking Water Act instructed the states (or local water suppliers) to address radon concentrations in community water systems (CWS). As an alternative to reducing waterborne radon concentrations in the CWS to the maximum contaminant level (MCL) of 11 Bq L(-1), states (or individual CWS) would be permitted to develop a multimedia mitigation (MMM) program, which allowed a greater concentration (148 Bq L(-1)) of waterborne radon in the CWS, if it could be shown that an equivalent health risk reduction could be achieved by reducing indoor radon concentrations. For a MMM program to be acceptable, the U.S. Environmental Protection Agency required the health-risk reduction attained through mitigations and radon-resistant new construction (RRNC) to offset the increased health risk due to radon in community water systems above the MCL of 11 Bq L(-1). A quantitative assessment indicates that the reduction in health risk currently achieved in New York State through radon mitigations and RRNC exceeded the increase in risk associated with an alternative MCL of 148 Bq L(-1). The implementation of a MMM program in New York would result in an overall reduction in the health risk associated with exposure to radon.

  4. MEASUREMENT AND REPORTING OF RADON EXPOSURES.

    PubMed

    2012-12-01

    Lung cancer risk caused by the inhalation of radon (222Rn) and its short-lived progeny is related to lung dose, which cannot be directly measured. The only measurable parameters which allow the determination of lung doses are the radon and radon progeny activity concentrations and related size distributions. Although lung cancers are caused by the inhaled short-lived radon progeny and not by the radon gas, it is the radon gas which is commonly measured and not its progeny. Since radon gas measurements are much easier to carry out, require less expensive equipment and are especially suited for long-term measurements, the report focuses on the measurement of the radon gas for specific exposure conditions in homes and workplaces. The first objective of this report is to provide information on how to measure radon, covering measurement techniques of radon in air and water, currently available detection systems, and measurement strategies most appropriate for the desired goal of a measurement campaign. Critical measurement strategy decisions are the selection of the measured radionuclide (i.e., radon gas or radon progeny and related size distributions), choice of the measurement period (i.e., short-term or long-term measurements), the choice of detector and its deployment, the type of measurement (i.e., areal or personal measurements), the survey strategy (i.e., integral or time-resolved measurements), or the strategy to accomplish the specific goal of a survey (i.e., measurements describing the current status or retrospective measurements). The choice of a specific strategy depends on the purpose of the survey, and differs therefore between the demands of a nation-wide indoor radon survey or an epidemiological study.The second objective of this report is how to interpret and report the results of these measurements, the associated uncertainties, and the resulting dosimetric estimates. Care should be taken when reporting and interpreting radon measurements because

  5. Radon mapping strategies in Austria.

    PubMed

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

    2015-11-01

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

  6. 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

  7. 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.

  8. Relating indoor NO 2 levels to infant personal exposures

    NASA Astrophysics Data System (ADS)

    Harlos, David P.; Marbury, Marian; Samet, Jonathan; Spengler, John D.

    We report here the results of a field survey of personal nitrogen dioxide exposure (PNO 2) of infants and simultaneous indoor NO 2 levels from various points throughout the infants' homes. Personal nitrogen dioxide levels can be predicted by average room NO 2 concentrations when appropriately weighted by infant presence in the room. Bedroom NO 2 concentration alone presents an alternative predictor which is more suitable for use in large scale surveys. Because of the typical infant's peculiar time-location patterns, they receive most of their NO 2 exposures in bedrooms (65 %)and living rooms (32 %), while the kitchen (5 %) and outdoor environments (> 2%)contribute only a small fraction of daily exposure. Average NO 2 exposure during cooking periods can be predicted using passive samplers placed directly over stoves and hours of stove use time.

  9. 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...

  10. The use of mechanical ventilation with heat recovery for controlling radon and radondaughter concentrations in houses

    NASA Astrophysics Data System (ADS)

    Nazaroff, W. W.; Boegel, M. L.; Hollowell, C. D.; Roseme, G. D.

    An energy research house in Maryland was found to have radon concentrations far in excess of recommended guidelines. A mechanical ventilation system with heat recovery was installed in this house to test its effectiveness as an energy-efficient control technique for indoor radon. Radon concentration was monitored continuously for 2 weeks under varying ventilation conditions [0.07-0.8 air changes per hour (ach)] and radondaughter concentrations were measured by grab-sample techniques about nine times daily during this period. At ventilation rates of 0.6 ach and higher, radon-daughter levels dropped below guidelines for indoor concentrations. Comparison with other studies indicates that indoor radon buildup may be a problem in a considerable portion of houses characterized by their low infiltration rates. The use of mechanical ventilation systems with air-to-air heat exchangers may offer a practical, cost-effective and energy-efficient means of alleviating not only the radon problem specifically but also the general deterioration of indoor air quality in many houses designed or retrofitted to achieve low infiltration.

  11. High radon areas in the Walloon region of Belgium.

    PubMed

    Tondeur, F; Cinelli, G; Dehandschutter, B

    2015-06-01

    Indoor radon data from Southern Belgium are organised in 35 geological units (GUs), most of which are homogeneous with respect to the radon risk. The percentage of cases above the reference level (400 Bq m(-3); 300 Bq m(-3) in the future) is calculated for these GUs from the observations and from the log-normal distribution fitted to the data. Affected areas are defined as areas with more than 1 % of houses above the reference level. In the north of the region, the old Palaeozoic basement is generally covered by Silesian, Cretaceous and Tertiary rocks, which are unaffected. The affected areas here are hot spots associated with specific Palaeozoic outcrops. In the south, there is generally no cover above Palaeozoic formations, which are often radon affected. The affected areas of Ardenne and Condroz dominate this part, but unaffected areas occur like Famenne and Gaume. About 48 % of the Walloon region is expected to be radon affected.

  12. 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.

  13. 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.

  14. Mapping the radon potential of the united states: Examples from the Appalachians

    USGS Publications Warehouse

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

    1997-01-01

    The geologic radon potential of the United States was recently assessed by the U.S. Geological Survey. Results indicate that approximately 33% of the U.S. population lives within geologic provinces where the average indoor radon levels have the potential to be greater than 4 pCi/L (147 Bq/m3). Rock types most commonly associated with high indoor radon include: 1) Uraniferous metamorphosed sediments, volcanics, and granite intrusives, especially those that are highly deformed or sheared. 2) Glacial deposits derived from uranium-bearing rocks and sediments. 3) Carboniferous, black shales. 4) Soils derived from carbonate rock, especially in karstic terrain. 5) Uraniferous fluvial, deltaic, marine, and lacustrine deposits. Different geologic terrains of the eastern United States illustrate some of the problems inherent in correlating indoor radon with geology. The Central and Southern Appalachian Highlands of the eastern United States have not been glaciated and most soils there are saprolitic, derived directly from the underlying bedrock. Regression analyses of bedrock geologic and radon parameters yield positive correlations (R > 0.5 to 0.9) and indicate that bedrock geology can account for a significant portion of the indoor radon variation. In glaciated areas of the United States such as the northern Appalachian Highlands and Appalachian Plateau, the correlation of bedrock geology to indoor radon is obscured or is positive only in certain cases. In these glaciated areas of the country, it is the type, composition, thickness, and permeability of glacial deposits, rather than the bedrock geology, that controls the radon source.

  15. APPLICATION OF RADON REDUCTION METHODS

    EPA Science Inventory

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

  16. Impact of haze-fog days to radon progeny equilibrium factor and discussion of related factors.

    PubMed

    Hou, Changsong; Shang, Bing; Zhang, Qingzhao; Cui, Hongxing; Wu, Yunyun; Deng, Jun

    2015-11-01

    The equilibrium factor F between radon and its short-lived progenies is an important parameter to estimate radon exposure of humans. Therefore, indoor and outdoor concentrations of radon and its short-lived radon progeny were measured in Beijing area using a continuously measuring device, in an effort to obtain information on the F value. The results showed that the mean values of F were 0.58 ± 0.13 (0.25-0.95, n = 305) and 0.52 ± 0.12 (0.31-0.91, n = 64) for indoor and outdoor, respectively. The indoor F value during haze-fog days was higher than the typical value of 0.4 recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation, and it was also higher than the values of 0.47 and 0.49 reported in the literature. A positive correlation was observed between indoor F values and PM2.5 concentrations (R (2) = 0.71). Since 2013, owing to frequent heavy haze-fog events in Beijing and surrounding areas, the number of the days with severe pollution remains at a high level. Future studies on the impact of the ambient fine particulate matter on indoor radon progeny equilibrium factor F could be important.

  17. Indoor Environment Program. 1992 Annual Report

    SciTech Connect

    Daisey, J.M.

    1993-06-01

    This paper reports progress during the year 1992 in the Indoor Environment Program in the Energy and Environment Division of Lawrence Berkeley Laboratory. Studies in the following areas are reported: energy performance and ventilation in buildings; physical and chemical characterization of indoor air pollutants; indoor radon; indoor air quality; exposure to indoor air pollutants and risk analysis. Pollutants of particular interest include: radon; volatile, semi-volatile and particulate organic compounds; and combustion emissions including environmental tobacco smoke, carbon monoxide, and nitrogen oxides.

  18. Home radon monitor modeled after the common smoke detector

    SciTech Connect

    Bolton, R.D.; Arnone, G.J.; Johnson, J.P.

    1995-02-01

    The EPA has declared that five million or so of the nation`s 80 million homes may have indoor radon levels that pose an unacceptably high risk of lung cancer to occupants. They estimate that four times as many people die from radon-induced lung cancers as from fires in the home. Therefore the EPA has recommended that all homes be tested and that action be taken to reduce the radon concentration in homes that test above the 4 pCi/L level. The push to have homeowners voluntarily test for elevated radon levels has been only marginally successful. A reliable, inexpensive, and accurate in-home radon monitor designed along the same general lines as a home smoke detector might overcome much of the public reluctance to test homes for radon. Such a Home Radon Monitor (HRM) is under development at Los Alamos National Laboratory. To be acceptable to the public, HRMs should have the following characteristics in common with smoke detectors: low cost, small size, ease of installation and use, low maintenance, and high performance. Recent advances in Long-Range Alpha Detection technology are being used in the design of a HRM that should meet or exceed all these characteristics. A proof-of-principle HRM detector prototype has been constructed and results from tests of this prototype will be presented.

  19. Fungal microcolonies on indoor surfaces — an explanation for the base-level fungal spore counts in indoor air

    NASA Astrophysics Data System (ADS)

    Pasanen, A.-L.; Heinonen-Tanski, H.; Kalliokoski, P.; Jantunen, M. J.

    In the subarctic winter, fungal spores are found in indoor air even when outdoor spore levels are very low. The results of this study support an explanation that some indoor airborne fungal spores are derived from unnoticeable fungal microcolonies, which may develop on temporarily wet surfaces. Laboratory experiments on Penicillium verrucosum indicated that the fungus germinated on new wallpaper very quickly (about half an hour) under moist conditions. Hyphal growth and sporulation of the fungus on moist wallpaper occured within one day of incubation. In gravity-settling tape samples from occasionally wet surfaces in a suburban home, large spore aggregates, hyphal fragments with some spores and spores in the germination stage were found, indicating fungal growth. These experiments showed that fungal microcolonies can develop within a week on occasionally wet indoor surfaces.

  20. Radon and lung cancer risk: taking stock at the millenium.

    PubMed Central

    Samet, J M; Eradze, G R

    2000-01-01

    Radon is a well-established human carcinogen for which extensive data are available, extending into the range of exposures experienced by the general population. Mounting epidemiologic evidence on radon and lung cancer risk, now available from more than 20 different studies of underground miners and complementary laboratory findings, indicates that risks are linear in exposure without threshold. Radon is also a ubiquitous indoor air pollutant in homes, and risk projections imply that radon is the second leading cause of lung cancer after smoking. Recommended control strategies in the United States and other countries, which include testing of most homes and mitigation of those exceeding guideline levels, have been controversial. Further research is needed, drawing on molecular and cellular approaches and continuing the follow-up of the underground miner cohorts, and scientists should work toward constructing mechanistically based models that combine epidemiologic and experimental data to yield risk estimates with enhanced certainty. Images Figure 1 Figure 2 PMID:10931781

  1. Geochemical and γ ray characterization of Pennsylvanian black shales: Implications for elevated home radon levels in Vanderburgh County, Indiana.

    PubMed

    Scheller, Kent W; Elliott, William S

    2015-10-01

    Radon ((222)Rn) is a radioactive gas that results from the decay of uranium ((238)U) in the Earth's crust. This study characterizes the presence and relative quantity of radon precursors in the Pennsylvanian black shales of southwest Indiana. Cores were drilled on the campus of the University of Southern Indiana to a depth of 237.7 m (780 ft) during exploration for coal-bed methane. Gamma ray logs were taken to measure radioactive activity as a function of depth in the bore hole. Activity readings of 270, 467, 555, and 388 GAPI (American Petroleum Institute γ ray units) were measured at depths of 124.3 m (408 ft), 154.0 m (505 ft), 187.1 m (614 ft) and 214.0 m (702 ft) in four separate shale layers of the Pennsylvanian stratigraphic column. GAPI units are used in the petroleum industry when drilling to represent the relative intensities of γ radiation from (40)K, (232)Th, and (238)U in bore holes (Belknap et al., 1959). For purposes of this study, the high activity readings on the gamma ray logs were used only to identify at which depths further gamma ray spectroscopy of the cores would be completed in the laboratory. Gamma ray spectroscopic studies of these cores were conducted with a large volume NaI crystal detector to observe γ rays of specific energies. Characteristic γ rays from various isotopes were identified confirming the presence and relative quantity of radon precursors in core samples. Geochemical analysis of cores was also conducted to measure presence and quantity of trace metals and radon precursors. Of 744 homes tested in Vanderburgh County from 2007 to 2013, 169 homes (22.7 percent) had elevated radon levels greater than 148 mBq L(-1) (4.0 pCi L(-1)). Additionally, 246 homes (33.1 percent) had measured radon levels of 74-145 mBq L(-1) (2.0-3.9 pCi L(-1)). About 80 percent of elevated radon levels greater than 148 mBq L(-1) (4.0 pCi L(-1)) are located in proximity to depositional contacts between the Dugger and Shelburn formations, or the

  2. EFFECTS OF NATURAL AND FORCED BASEMENT VENTILATION ON RADON LEVELS IN SINGLE FAMILY DWELLINGS

    EPA Science Inventory

    The report gives, for the first time, results of an extensive study of the effect of ventilation on radon concentrations and radon entry rate in a single-family dwelling. Measurements of radon concentrations, building dynamics, and environmental parameters made in Princeton Unive...

  3. Indoor secondhand tobacco smoke emission levels in six Lebanese cities

    PubMed Central

    Saade, Georges; Seidenberg, Andrew B; Otrock, Zaher; Connolly, Gregory N

    2010-01-01

    Background To date, Lebanon has failed to enact comprehensive clean indoor air laws despite ratification of the Framework Convention on Tobacco Control (FCTC), which calls for the protection of non-smokers from exposure to secondhand tobacco smoke (SHS). Complicating the problem of SHS exposure in Lebanon is the widespread use of the tobacco water-pipe. While most research on SHS has involved cigarette smoking as a source of emissions, other sources, including tobacco water-pipes, may be an important contributor. Methods PM2.5 concentrations (μg/m3) were measured in a sample of 28 public venues located in six major Lebanese cities. Active smoker density (number of smokers/100 m3) was calculated for both water-pipe and cigarette smokers. Venues were then categorised as having higher density of water-pipe smokers or higher density of cigarette smokers, and resultant emission levels were compared between the two groups. Results Cigarette and water-pipe smoking was observed in 14 venues, while cigarette smoking only and water-pipe smoking only were found in 12 venues and one venue, respectively. Among all smoking-permitted venues, the mean PM2.5 concentration was 342 μg/m3. Venues with a higher density of water-pipe smokers (n =14) showed a similar median PM2.5 concentration (349 μg/m3) compared with venues with a higher density of cigarette smokers (n =13; 241 μg/m3; p=0.159). The mean PM2.5 concentration in the single venue with a voluntary smoke-free policy was 6 μg/m3. Conclusions Despite ratification of the FCTC in 2005, both cigarette and water-pipe smoking are commonly practised in enclosed public places throughout Lebanon, leading to unsafe levels of indoor particulate pollution. Smoke-free policies are needed in Lebanon to protect the public's health, and should apply to all forms of tobacco smoking. PMID:20378588

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

    PubMed Central

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

    2015-01-01

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

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

    SciTech Connect

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

    2014-02-12

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

  6. The radon indicator

    NASA Astrophysics Data System (ADS)

    Samuelsson, L.

    2005-11-01

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

  7. Radon reduction and radon monitoring in the NEMO experiment

    SciTech Connect

    Nachab, A.

    2007-03-28

    The first data of the NEMO 3 neutrinoless double beta decay experiment have shown that the radon can be a non negligible component of the background. In order to reduce the radon level in the gas mixture, it has been necessary first to cover the NEMO 3 detector with an airtight tent and then to install a radon-free air factory. With the use of sensitive radon detectors, the level of radon at the exit of the factory and inside the tent is continuously controlled. These radon levels are discussed within the NEMO 3 context.

  8. USACE FUSRAP Maywood Team Develops a Mechanism to Evaluate Residual Radon Exposure Potential at Vicinity Properties Where Remediation of Accessible Contamination has been Completed

    SciTech Connect

    Winters, M.; Walnicki, S.; Hays, D.

    2008-07-01

    The Maywood FUSRAP Team is obligated, under its approved remedy selection decision document, to demonstrate substantive compliance with New Jersey Administrative Code 7:28- 12(a)2, establishing an indoor limit of three Pico-Curies per liter above background for radon-222 (Rn-222). The Maywood Team explores various avenues for dealing with the radon issue and provides an alternative for demonstrating substantive compliance with the radon remediation standard by answering the question: 'In certain conservative situations, can compliance with the radon standard be demonstrated without performing monitoring?' While monitoring may be the most definitive method for demonstrating compliance, a logical argument can be made that when radiological remediation removes the potential source for Rn-222 above background, monitoring is unnecessary. This position is defended through the use of historical physical radon measurements which illustrate that indoor radon was not a pre-remediation problem, and post-remediation soil sampling data which demonstrate that the source of the potentially elevated Rn- 222 levels have been successfully mitigated. Monitoring recommendations are made for situations where insufficient data exists to make definitive determinations or when un-remediated sources affecting habitable structures remain on a given property. Additional information regarding recommended techniques and references for effective monitoring of indoor radon are included in this paper. This paper may benefit teams that have similar regulatory commitments and/or have need to make assessments of radon exposure potential based upon historical monitoring data and available soils concentration data. (authors)

  9. Radon potential mapping of the Tralee-Castleisland and Cavan areas (Ireland) based on airborne gamma-ray spectrometry and geology.

    PubMed

    Appleton, J D; Doyle, E; Fenton, D; Organo, C

    2011-06-01

    The probability of homes in Ireland having high indoor radon concentrations is estimated on the basis of known in-house radon measurements averaged over 10 km × 10 km grid squares. The scope for using airborne gamma-ray spectrometer data for the Tralee-Castleisland area of county Kerry and county Cavan to predict the radon potential (RP) in two distinct areas of Ireland is evaluated in this study. Airborne data are compared statistically with in-house radon measurements in conjunction with geological and ground permeability data to establish linear regression models and produce radon potential maps. The best agreement between the percentage of dwellings exceeding the reference level (RL) for radon concentrations in Ireland (% > RL), estimated from indoor radon data, and modelled RP in the Tralee-Castleisland area is produced using models based on airborne gamma-ray spectrometry equivalent uranium (eU) and ground permeability data. Good agreement was obtained between the % > RL from indoor radon data and RP estimated from eU data in the Cavan area using terrain specific models. In both areas, RP maps derived from eU data are spatially more detailed than the published 10 km grid map. The results show the potential for using airborne radiometric data for producing RP maps.

  10. Radon exposure and lung cancer risk--Czech cohort study on residential radon.

    PubMed

    Tomásek, L; Kunz, E; Müller, T; Hůlka, J; Heribanová, A; Matzner, J; Placek, V; Burian, I; Holecek, J

    2001-05-14

    Epidemiological evidence of lung cancer risk from radon is based mainly on studies of men employed underground in mines where exposures are relatively high in comparison to indoor exposure. Nevertheless, direct evidence of risk from residential radon is desirable. In 1990, a study was started comprising 12,000 inhabitants of an area with elevated radon concentrations. The mean level in the houses was higher than general mean of the country by a factor of five. In the period 1961-1995, a total of 173 lung cancers were observed. Comparing to nationally expected numbers (E), the observed number (O) of cases is elevated (O/E = 1.11), in contrast to generally low figures for cancers other than lung (O/E = 0.85). Lung cancer risk related to cumulative exposures experienced in the past 5-24 or 5-35 years were both significant. In relation to standard radon progeny concentration 100 Bq/m3, the excess relative risk coefficient was 0.103 (95% CI, 0.039-0.168), the value somewhat lower than findings in other indoor studies.

  11. RADON MITIGATION IN SCHOOLS: HVAC SYTEMS IN SCHOOLS TEND TO HAVE A GREATER IMPACT ON RADON LEVELS THAN HVAC SYSTEMS IN HOMES

    EPA Science Inventory

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

  12. Indoor air quality large building characterization project planning. Report for September 1992--May 1997

    SciTech Connect

    Menetrez, M.Y.; Kulp, R.N.; Pyle, B.; Williamson, A.; McDonough, S.

    1998-08-01

    Three buildings were characterized in this project by examining radon concentrations and indoor air quality (IAQ) levels as affected by building ventilation dynamics. IAQ data collection stations (IAQDS) for monitoring and data logging, remote switches (pressure and sail switches), and a weather station were installed. Measurements of indoor radon carbon dioxide, particle concentrations, temperature, humidity, pressure differentials, ambient and sub-slab radon concentrations, and outdoor air (OA) intake flow rates were collected. The OA intake was adjusted when possible, and fan cycles were controlled while tracer gas measurements were taken in all zones and IAQDS data were collected. Ventilation, infiltration, mixing rates, radon entry, pressure/temperature convective driving forces, CO{sub 2} generation/decay rates, and IAQ levels were established for baseline and OA-adjusted conditions.

  13. Home energy efficiency and radon related risk of lung cancer: modelling study

    PubMed Central

    Milner, James; Shrubsole, Clive; Das, Payel; Jones, Benjamin; Ridley, Ian; Chalabi, Zaid; Hamilton, Ian; Armstrong, Ben; Davies, Michael

    2014-01-01

    Objective To investigate the effect of reducing home ventilation as part of household energy efficiency measures on deaths from radon related lung cancer. Design Modelling study. Setting England. Intervention Home energy efficiency interventions, motivated in part by targets for reducing greenhouse gases, which entail reduction in uncontrolled ventilation in keeping with good practice guidance. Main outcome measures Modelled current and future distributions of indoor radon levels for the English housing stock and associated changes in life years due to lung cancer mortality, estimated using life tables. Results Increasing the air tightness of dwellings (without compensatory purpose-provided ventilation) increased mean indoor radon concentrations by an estimated 56.6%, from 21.2 becquerels per cubic metre (Bq/m3) to 33.2 Bq/m3. After the lag in lung cancer onset, this would result in an additional annual burden of 4700 life years lost and (at peak) 278 deaths. The increases in radon levels for the millions of homes that would contribute most of the additional burden are below the threshold at which radon remediation measures are cost effective. Fitting extraction fans and trickle ventilators to restore ventilation will help offset the additional burden but only if the ventilation related energy efficiency gains are lost. Mechanical ventilation systems with heat recovery may lower radon levels and the risk of cancer while maintaining the advantage of energy efficiency for the most airtight dwellings but there is potential for a major adverse impact on health if such systems fail. Conclusion Unless specific remediation is used, reducing the ventilation of dwellings will improve energy efficiency only at the expense of population wide adverse impact on indoor exposure to radon and risk of lung cancer. The implications of this and other consequences of changes to ventilation need to be carefully evaluated to ensure that the desirable health and environmental benefits of

  14. Radon, thoron and their progeny levels in some dwellings of northern Haryana, India using SSNTDs

    NASA Astrophysics Data System (ADS)

    Saini, R. S.; Nain, Mahabir; Chauhan, R. P.; Kishore, Nawal; Chakarvarti, S. K.

    2009-08-01

    Radon pollution is an important global problem of radiation hygiene. Radon and its progeny are the major contributors in the radiation dose received by general population of the world. Keeping this in mind the environmental monitoring of radon, thoron and their progeny in some dwellings of northern part of Haryana state of India has been carried out. The radon-thoron twin dosimeter cups were used for the study. The aim of the study is the possible health risk assessment in the dwellings under consideration.

  15. Seasonal Variability in European Radon Measurements

    NASA Astrophysics Data System (ADS)

    Groves-Kirkby, C. J.; Denman, A. R.; Phillips, P. S.; Crockett, R. G. M.; Sinclair, J. M.

    2009-04-01

    In temperate climates, domestic radon concentration levels are generally seasonally dependent, the level in the home reflecting the convolution of two time-dependent functions. These are the source soil-gas radon concentration itself, and the principal force driving radon into the building from the soil, namely the pressure-difference between interior and exterior environment. While the meteorological influence can be regarded as relatively uniform on a European scale, its variability being defined largely by the influence of North-Atlantic weather systems, soil-gas radon is generally more variable as it is essentially geologically dependent. Seasonal variability of domestic radon concentration can therefore be expected to exhibit geographical variability, as is indeed the case. To compensate for the variability of domestic radon levels when assessing the long term radon health risks, the results of individual short-term measurements are generally converted to equivalent mean annual levels by application of a Seasonal Correction Factor (SCF). This is a multiplying factor, typically derived from measurements of a large number of homes, applied to the measured short-term radon concentration to provide a meaningful annual mean concentration for dose-estimation purposes. Following concern as to the universal applicability of a single SCF set, detailed studies in both the UK and France have reported location-specific SCF sets for different regions of each country. Further results indicate that SCFs applicable to the UK differ significantly from those applicable elsewhere in Europe and North America in both amplitude and phase, supporting the thesis that seasonal variability in indoor radon concentration cannot realistically be compensated for by a single national or international SCF scheme. Published data characterising the seasonal variability of European national domestic radon concentrations, has been collated and analysed, with the objective of identifying

  16. Evaluation and equity audit of the domestic radon programme in England.

    PubMed

    Zhang, Wei; Chow, Yimmy; Meara, Jill; Green, Martyn

    2011-09-01

    The U.K. has a radon programme to limit the radon risk to health. This involves advice on protective measures in new buildings, technical guidance on their installation, encouragement of radon measurements and remediation in existing dwellings in high radon areas. We have audited the radon programme at the level of individual homes to identify factors that influence the likelihood of remediation. 49% of the householders responded to our survey and 30% of the respondents stated that they had done some remediation to reduce the indoor radon levels. We found that householders with higher incomes and higher socio-economic status are more likely than others to remediate. Householders are less likely to remediate if they have one of the following: living in a property with a high radon concentration, current smokers in the dwelling, being unemployed or an unskilled worker, long length of time living in that property or elderly (65+ years) living by themselves. Householders appeared to be more likely to remediate if they considered the information on radon and its risk to be very clear and useful. This emphasises the importance of communication with householders.

  17. Political Factors Affecting the Enactment of State-Level Clean Indoor Air Laws

    PubMed Central

    Vernick, Jon S.; Stuart, Elizabeth A.; Webster, Daniel W.

    2014-01-01

    Objectives. We examined the effects of key political institutional factors on the advancement of state-level clean indoor air laws. Methods. We performed an observational study of state-level clean indoor air law enactment among all 50 US states from 1993 to 2010 by using extended Cox hazard models to assess risk of enacting a relevant law. Results. During the 18-year period from 1993 to 2010, 28 states passed a law covering workplaces, 33 states passed a law covering restaurants, 29 states passed a law covering bars, and 16 states passed a law covering gaming facilities. States with term limits had a 2.15 times greater hazard (95% confidence interval [CI] = 1.27, 3.65; P = .005) of enacting clean indoor air laws. The presence of state-level preemption of local clean indoor air laws was associated with a 3.26 times greater hazard (95% CI = 1.11, 9.53; P = .031) of state-level policy enactment. In the presence of preemption, increased legislative professionalism was strongly associated (hazard ratio = 3.28; 95% CI = 1.10, 9.75; P = .033) with clean indoor air law enactment. Conclusions. Political institutional factors do influence state-level clean indoor air law enactment and may be relevant to other public health policy areas. PMID:24825239

  18. HIGH TEMPERATURE TREATMENT OF INTERMEDIATE-LEVEL RADIOACTIVE WASTES - SIA RADON EXPERIENCE

    SciTech Connect

    Sobolev, I.A.; Dmitriev, S.A.; Lifanov, F.A.; Kobelev, A.P.; Popkov, V.N.; Polkanov, M.A.; Savkin, A.E.; Varlakov, A.P.; Karlin, S.V.; Stefanovsky, S.V.; Karlina, O.K.; Semenov, K.N.

    2003-02-27

    This review describes high temperature methods of low- and intermediate-level radioactive waste (LILW) treatment currently used at SIA Radon. Solid and liquid organic and mixed organic and inorganic wastes are subjected to plasma heating in a shaft furnace with formation of stable leach resistant slag suitable for disposal in near-surface repositories. Liquid inorganic radioactive waste is vitrified in a cold crucible based plant with borosilicate glass productivity up to 75 kg/h. Radioactive silts from settlers are heat-treated at 500-700 0C in electric furnace forming cake following by cake crushing, charging into 200 L barrels and soaking with cement grout. Various thermochemical technologies for decontamination of metallic, asphalt, and concrete surfaces, treatment of organic wastes (spent ion-exchange resins, polymers, medical and biological wastes), batch vitrification of incinerator ashes, calcines, spent inorganic sorbents, contaminated soil, treatment of carbon containing 14C nuclide, reactor graphite, lubricants have been developed and implemented.

  19. Identification and mapping of radon-prone areas in Croatia-preliminary results for Lika-Senj and the southern part of Karlovac counties.

    PubMed

    Radolić, Vanja; Miklavčić, Igor; Stanić, Denis; Poje, Marina; Krpan, Ivana; Mužević, Matko; Petrinec, Branko; Vuković, Branko

    2014-11-01

    Long-term indoor radon measurements performed by LR 115 track etched detectors in Croatian homes during 2003-04 showed that the arithmetic means of radon concentrations in Lika-Senj and the southern part of Karlovac counties were three times higher (198 Bq m(-3)) than in houses at national level (68 Bq m(-3)). Recently, indoor radon measurements in randomly selected houses were investigated. The obtained values in these new measurements have confirmed the values obtained 10 y ago (the average radon value in 225 investigated houses in this area is 223 Bq m(-3)). Radon concentrations in soil gas were measured in September and October 2012 and 2013 with the AlphaGUARD measuring system. Areas with both elevated indoor radon levels and radon in soil gas were identified (some micro locations in Korenica, Ličko Lešće, Generalski Stol, Slunj and Ogulin) and visually presented in the form of maps using the inverse distance weighting approach.

  20. A study of airborne radon levels in Paarl houses (South Africa) and associated source terms, using electret ion chambers and gamma-ray spectrometry.

    PubMed

    Lindsay, R; Newman, R T; Speelman, W J

    2008-11-01

    Indoor radon ((222)Rn) concentrations were measured in Paarl homes by means of electret ion chambers. The concentrations varied between 28 and 465 Bq m(-3). The average values (Bq m(-3)) found in houses on the west and east side of the Berg River, which bisects Paarl, were 132 (+/-11) and 37 (+/-3), respectively. Radiometric analyses of soils show that the mean (226)Ra activity concentration is three times higher on the west than on the east side of the Berg River.

  1. Measurement and reduction of low-level radon background in the KATRIN experiment

    SciTech Connect

    Fränkle, F. M.

    2013-08-08

    The KArlsruhe TRItium Neutrino (KATRIN) experiment is a next generation, model independent, large scale experiment to determine the mass of the electron anti-neutrino by investigating the kinematics of tritium beta decay with a sensitivity of 200 meV/c{sup 2}. The measurement setup consists of a high luminosity windowless gaseous molecular tritium source (WGTS), a differential and cryogenic pumped electron transport and tritium retention section, a tandem spectrometer section (pre-spectrometer and main spectrometer) for energy analysis, followed by a detector system for counting transmitted beta decay electrons. Measurements performed at the KATRIN pre-spectrometer test setup showed that the decay of radon (Rn) atoms in the volume of the KATRIN spectrometers is a major background source. Rn atoms from low-level radon emanation of materials inside the vacuum region of the KATRIN spectrometers are able to penetrate deep into the magnetic flux tube so that the alpha decay of Rn contributes to the background. Of particular importance are electrons emitted in processes accompanying the Rn alpha decay, such as shake-off, internal conversion of excited levels in the Rn daughter atoms and Auger electrons. Lowenergy electrons (< 100 eV) directly contribute to the background in the signal region. High-energy electrons can be stored magnetically inside the volume of the spectrometer and are able to create thousands of secondary electrons via subsequent ionization processes with residual gas molecules. In order to reduce the Rn induced background different active and passive counter measures were developed and tested. This proceeding will give an overview on Rn sources within the KATRIN spectrometer, describes how Rn decays inside the spectrometer produce background events at the detector and presents different counter measures to reduce the Rn induced background.

  2. A Pilot Study to Examine Exposure to Residential Radon in Under-Sampled Census Tracts of DeKalb County, Georgia, in 2015

    PubMed Central

    Stauber, Christine E.; Dai, Dajun; Chan, Sydney R.; Diem, Jeremy E.; Weaver, Scott R.; Rothenberg, Richard

    2017-01-01

    While DeKalb County, Georgia, offers free radon screening for all eligible residents, portions of the county remain relatively under-sampled. This pilot study focused on 10% of the census tracts in the county with the lowest proportion of radon testing; most were in southern DeKalb County. In total, 217 households were recruited and homes were tested for indoor radon concentrations on the lowest livable floor over an eight-week period from March–May 2015. Tract-level characteristics were examined to understand the differences in socio-demographic and economic factors between the pilot study area and the rest of the county. The pilot study tracts had a higher proportion of African Americans compared to the rest of DeKalb County (82% versus 47%). Radon was detected above 11.1 Bq/m3 (0.3 pCi/L) in 73% of the indoor samples and 4% of samples were above 148 Bq/m3 (4 pCi/L). Having a basement was the strongest predictive factor for detectable and hazardous levels of radon. Radon screening can identify problems and spur homeowners to remediate but more research should be done to identify why screening rates vary across the county and how that varies with radon levels in homes to reduce radon exposure. PMID:28327511

  3. Children’s Exposure to Radon in Nursery and Primary Schools

    PubMed Central

    Branco, Pedro T. B. S.; Nunes, Rafael A. O.; Alvim-Ferraz, Maria C. M.; Martins, Fernando G.; Sousa, Sofia I. V.

    2016-01-01

    The literature proves an evident association between indoor radon exposure and lung cancer, even at low doses. This study brings a new approach to the study of children’s exposure to radon by aiming to evaluate exposure to indoor radon concentrations in nursery and primary schools from two districts in Portugal (Porto and Bragança), considering different influencing factors (occupation patterns, classroom floor level, year of the buildings’ construction and soil composition of the building site), as well as the comparison with IAQ standard values for health protection. Fifteen nursery and primary schools in the Porto and Bragança districts were considered: five nursery schools for infants and twelve for pre-schoolers (seven different buildings), as well as eight primary schools. Radon measurements were performed continuously. The measured concentrations depended on the building occupation, classroom floor level and year of the buildings’ construction. Although they were in general within the Portuguese legislation for IAQ, exceedances to international standards were found. These results point out the need of assessing indoor radon concentrations not only in primary schools, but also in nursery schools, never performed in Portugal before this study. It is important to extend the study to other microenvironments like homes, and in time to estimate the annual effective dose and to assess lifetime health risks. PMID:27043596

  4. Methodology issues in risk assessment for radon.

    PubMed Central

    Harley, N H

    1991-01-01

    The alpha dose per unit radon daughter exposure in mines and homes is comparable at about 5 mGy/WLM. This means that excess lung cancer risk determined in follow-up studies of miners should be valid to extrapolating to environmental populations. There are several models currently used for risk projection to estimate lung cancer in the U.S. from indoor radon exposure. The accuracy of the estimates depends upon the quality of the exposure data and the models. Recent miner epidemiology confirms that excess lung cancer risk decreases with time subsequent to cessation of exposure. The most rigorous ecological study, to date, shows a persistent negative relationship between average measured indoor radon in U.S. counties and lung cancer mortality. A model for lung cancer risk is proposed that includes smoking, urbanization, and radon exposure. The model helps to explain the difficulties in observing the direct effects of indoor radon in the environment. PMID:2050058

  5. Requirements relating to radon in the International Basic Safety Standards: information, measurement and national strategies.

    PubMed

    Colgan, P A; Boal, T; Czarwinski, R

    2013-03-01

    The fifth edition of the International Basic Safety Standards (BSS) has recently been established as Part 3 of the General Safety Requirements of the IAEA Safety Standards Series. The BSS applies to all exposure situations and to all categories of exposure. As such, the BSS addresses both occupational exposure due to radon in workplaces and public exposure due to radon in dwellings. In workplaces, exposure due to radon is treated either as a planned exposure situation or as an existing exposure situation, depending on the circumstances. With regard to exposure due to radon in dwellings, the BSS requires that general information on radon, including information on health risks and the synergy with smoking, be made available to the public and other interested parties. Countries are also required to determine whether an action plan for controlling exposure due to radon indoors is necessary, and, if so, to establish and implement such an action plan. Guidance material, covering the establishment of reference levels, national and regional radon surveys, identification of radon prone areas, building codes for new buildings, corrective actions for existing buildings, information campaigns and programme evaluation and effectiveness is currently being developed.

  6. Ingredients for a Dutch radon action plan, based on a national survey in more than 2500 dwellings.

    PubMed

    Smetsers, R C G M Ronald; Blaauboer, R O Roelf; Dekkers, S A J Fieke

    2016-12-01

    A new Euratom directive demands that Member States establish a national action plan for indoor radon. Important requirements are a national reference level for the radon concentration in dwellings, actions to identify dwellings with radon concentrations that might exceed this reference level and the encouragement of appropriate measures to reduce the radon concentrations in dwellings where these are high. This paper provides ingredients and recommendations for a national action plan for radon in dwellings, applicable to the Netherlands. The approach presented here, which may serve as a model for other countries or regions with a comparatively favourable indoor radon situation, is based on the analysis of radon data from a national survey in more than 2500 Dutch dwellings, built since 1930. The annual average activity concentration of radon in dwellings in the Netherlands equals 15.6 ± 0.3 Bq m(-3). The 50th and 95th percentiles were found to be 12.2 and 38.0 Bq m(-3), respectively. In 0.4 per cent of the dwellings we found values above 100 Bq m(-3). Radon concentrations showed correlations with type of dwelling, year of construction, ventilation system, soil type and smoking behaviour of inhabitants. The survey data suggest that it is feasible for the Netherlands to adopt a national reference level for radon in dwellings of 100 Bq m(-3), in line with recommendations by WHO and ICRP. We were able to predict dwellings with a moderate probability for radon concentrations above 100 Bq m(-3) by applying a combination of three selection criteria: location, type of dwelling and manner of ventilation. Of the existing 6.2 million dwellings in the Netherlands (built since 1930), approximately 23-24 thousand are suspected to exceed this level. Some 80% of these are found in the group of naturally ventilated single-family dwellings in either the southern part of Limburg (approx. 13 thousand) or the Meuse-Rhine-Waal river delta (approx. six thousand). This selected

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

    PubMed

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

    2016-10-01

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

  8. A prediction model for assessing residential radon concentration in Switzerland.

    PubMed

    Hauri, Dimitri D; Huss, Anke; Zimmermann, Frank; Kuehni, Claudia E; Röösli, Martin

    2012-10-01

    Indoor radon is regularly measured in Switzerland. However, a nationwide model to predict residential radon levels has not been developed. The aim of this study was to develop a prediction model to assess indoor radon concentrations in Switzerland. The model was based on 44,631 measurements from the nationwide Swiss radon database collected between 1994 and 2004. Of these, 80% randomly selected measurements were used for model development and the remaining 20% for an independent model validation. A multivariable log-linear regression model was fitted and relevant predictors selected according to evidence from the literature, the adjusted R², the Akaike's information criterion (AIC), and the Bayesian information criterion (BIC). The prediction model was evaluated by calculating Spearman rank correlation between measured and predicted values. Additionally, the predicted values were categorised into three categories (50th, 50th-90th and 90th percentile) and compared with measured categories using a weighted Kappa statistic. The most relevant predictors for indoor radon levels were tectonic units and year of construction of the building, followed by soil texture, degree of urbanisation, floor of the building where the measurement was taken and housing type (P-values <0.001 for all). Mean predicted radon values (geometric mean) were 66 Bq/m³ (interquartile range 40-111 Bq/m³) in the lowest exposure category, 126 Bq/m³ (69-215 Bq/m³) in the medium category, and 219 Bq/m³ (108-427 Bq/m³) in the highest category. Spearman correlation between predictions and measurements was 0.45 (95%-CI: 0.44; 0.46) for the development dataset and 0.44 (95%-CI: 0.42; 0.46) for the validation dataset. Kappa coefficients were 0.31 for the development and 0.30 for the validation dataset, respectively. The model explained 20% overall variability (adjusted R²). In conclusion, this residential radon prediction model, based on a large number of measurements, was demonstrated to be robust

  9. Combined stack effect in houses and eskers explaining transients in radon source.

    PubMed

    Schmied, H

    1985-10-01

    Concentrations of radon indoors and temperatures indoors and outdoors have been recorded every hour with some interruptions for one 12-week period in a dwelling situated on top of an esker outside Stockholm. The concentration of radon in the house shows variations, which can be explained as a combined stack effect in the esker and in the building. The stack effect is not only dependent on temperature differences, but also on the pressure effect that the wind creates. In this study no local wind observations have been made as this was not the main purpose on this occasion. The temperature in the esker is assumed to be at a constant level equivalent to groundwater temperature. From these data the pressure gradient has been calculated and then compared with the radon source.

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

    NASA Astrophysics Data System (ADS)

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

    2008-08-01

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

  11. Estimated risks of radon-induced lung cancer for different exposure profiles based on the new EPA model.

    PubMed

    Chen, Jing

    2005-04-01

    Radon is a naturally occurring radioactive gas. When inhaled, radon can cause mutations that lead to lung cancer. Some new epidemiologic studies indicate that indoor radon is a public health problem. The BEIR VI report outlined its preferred two risk models for the combined effects of smoking and exposure to radon progeny, and listed the estimated risk to ever-smokers and never-smokers of both sexes due to lifetime exposure. However, exposures for shorter periods of time are of practical interest since exposure to elevated levels of radon may occur and end at any age. This study aims to produce practical tables of lifetime relative risks for exposures between any two age intervals from 0 to 110, and for various radon concentrations found in homes from 100 to 1,000 Bq m(-3). The calculations are based on the risk model developed recently by U.S. Environmental Protection Agency. The EPA's risk model is a single model that gives risk values midway between those obtained from the two BEIR VI preferred models. The detailed tables provide a clearer view of the age groups at higher risk and the effect of exposure duration. The results will help radiation protection practitioners to better communicate indoor radon risk to members of the public.

  12. Radon: The Silent Danger.

    ERIC Educational Resources Information Center

    Stoffel, Jennifer

    1989-01-01

    This article discusses the public health dangers associated with radon exposure in homes and schools. In addition, testing and corrective efforts by federal and state agencies are discussed. A map indicating areas in the U.S. with potentially high radon levels is included. (IAH)

  13. Radon: a bibliography

    SciTech Connect

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

    1981-01-01

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

  14. Radon levels and doses in dwellings in two villages in Kosovo, affected by depleted uranium.

    PubMed

    Nafezi, G; Gregoric, A; Vaupotic, J; Bahtijari, M; Kuqali, M

    2014-01-01

    The radon ((222)Rn) activity concentration in 15 dwellings in the Planej village and 10 dwellings in the Gorozhup village has been measured with the aim to complement the national radon survey and to compare the results of two different measurement techniques. The radon concentration has been measured in winter and spring using alpha scintillation cells and in winter, spring and summer by exposing solid-state nuclear track detectors. Both methods gave similar results. Radon concentrations in both villages were similar, ranging from 82 to 432 Bq m(-3); the value of 400 Bq m(-3) was exceeded only in two dwellings. The resulting annual effective doses ranged from 1.78 to 6.40 mSv, with the average values of 3.28 mSv in the Planej village and 3.87 mSv in the Gorozhup village.

  15. Test Your Home for Radon, You May Prevent Lung Cancer Radon kills 21,000 Americans each year, readily available tests can warn of high levels in homes

    EPA Pesticide Factsheets

    (01/15/16 -Atlanta) - January is National Radon Action Month and the U.S. Environmental Protection Agency (EPA) encourages Americans around the country to test their homes for radon, the second leading cause of lung cancer. Make 2016 a healthier, safer new

  16. Demonstrating effectiveness of passive radon-resistant new construction.

    PubMed

    LaFollette, S; Dickey, T

    2001-01-01

    Fifty percent of homes tested for radon in Rock Island County, IL, have radon levels above the U.S. Environmental Protection Agency (EPA) action guideline of 4 picoCuries per liter (pCi/L) of air. Therefore, the county is classified by the EPA as Zone 1 on the EPA's Map of Radon Potential. Radon-resistant new construction (RRNC) strategies for new homes are recommended by the EPA in Zone 1 areas. One city in the county, East Moline, reduced the cost of building permits for contractors volunteering to build new homes incorporating modified passive RRNC. Forty-six of 124 new homes built with passive RRNC in the city were tested during this study. Only 27 of the homes tested were below 4-pCi/L, justifying the importance of testing the system to ensure levels are below the action guideline. To provide additional support to an argument in favor of changing city building codes to the required RRNC, 23 of the homes were also tested with the systems deactivated. After systems were deactivated, 73% of the homes had radon levels above the action guideline. Four homes were sampled for bioaerosols to evaluate if passive RRNC might impact other indicators of poor indoor air quality (IAQ). The results of the research will be discussed here.

  17. Radon levels in drinking water and soil samples of Jodhpur and Nagaur districts of Rajasthan, India.

    PubMed

    Mittal, Sudhir; Rani, Asha; Mehra, Rohit

    2016-07-01

    Radon causes lung cancer when it is trapped inside the lungs. Therefore it is very important to analyze the radon concentration in water and soil samples. In the present investigation, water and soil samples collected from 20 different locations of Jodhpur and Nagaur districts of Northern Rajasthan, India have been studied by using RAD7. The measured radon concentration in water samples varies from 0.5 to 15Bql(-1). The observed values lie within the safe limit as set by UNSCEAR, 2008. The total annual effective dose due to radon in water corresponding to all studied locations has been found to be well within the safe limit of 0.1mSvy(-1) as recommended by World Health Organization (WHO, 2004) and European Council (EU, 1998). The measurements carried out on radon concentration in soil samples reveal a variation from 1750 to 9850Bqm(-3). These results explore that the water of Jodhpur and Nagaur districts is suitable for drinking purpose without posing any health hazard but soil hazards depend upon its permeability and radon concentration.

  18. Physical conditions of a house and their effects on measured radon levels: data from Hillsborough Township, New Jersey, 2010-2011.

    PubMed

    Shendell, Derek G; Carr, Michael

    2013-10-01

    Concentrations of radon in homes are thought to be dependent on several factors, including the presence of certain physical conditions of the house that act as entry points for this colorless, odorless gas. Drains and sump pits are currently sealed as part of radon mitigation, but doing so may cause drainage problems and mold. The authors attempted to determine if specific attributes and physical conditions of homes are associated with measured residential concentrations of radon. Radon tests were conducted in 96 participating homes in rural Hillsborough Township, New Jersey, November 2010-February 2011. Samplers were placed and a walk-through survey was conducted. Test devices were analyzed by a New Jersey certified radon testing laboratory and results compared to survey data. Overall, 50% of houses with a perimeter drain and 30% of houses with a sump pit exceeded the New Jersey and federal radon action level of 4.0 picocuries per liter, and 47% of homes with both a sump and a perimeter "French" drain exceeded this action level. The authors' results suggested certain physical conditions act as pathways allowing radon entry into homes. Results could be used by local and state agencies to start local initiatives, e.g., increased testing or to seal these components as partial mitigation.

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

    PubMed

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

    2008-10-01

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

  20. Contribution to indoor ozone levels of an ozone generator. Final report, April 1990-December 1992

    SciTech Connect

    Steiber, R.S.

    1993-09-01

    The report gives results of a study of a commonly used commercially available ozone generator, undertaken to determine its impact on indoor ozone levels. Experiments were conducted in a typical mechanically ventilated office and in a test house. The generated ozone and the in-room ozone concentrations were measured. The results showed that, when the unit was operated at the manufacturer's recommended setting, it generated little if any ozone. The indoor concentrations in the case were not significantly above natural background. When operated at the maximum setting, the generator produced large amounts of ozone: over 100 ppb in well ventilated spaces, and nearly 1 ppm in poorly ventilated spaces. When the ozone generator was turned off, ozone levels quickly returned to background. No measurements were made to determine the effect of the device on other aspects of indoor air quality, such as the elimination of volatile organic compounds.

  1. In situ measurements of radon levels in water and soil and exhalation rate in areas of Malwa belt of Punjab (India).

    PubMed

    Kumar, Sanjeev; Singh, Surinder; Bajwa, Bikramjit S; Sabharwal, Arvind D

    2011-12-01

    Radon concentration levels in water and soil gas from 36 locations pertaining to some areas of Malwa region of Punjab have been measured on an in situ basis using a continuous active radon detector (AlphaGuard, Model - PQ 2000 PRO, Genitron instruments, Germany). Exhalation rate measurements have also been carried out at these places, using a closed-circuit technique. The radon concentrations in soil and water varied from 1.9 to 16.4 kBq m(-3) and 5.01 to 11.6 kBq m(-3), respectively. The exhalation rate (E (Rn)) ranged between 7.48 and 35.88 mBq m(-2) s(-1) with an average value of 18.17 mBq m(-2) s(-1). Annual dose rates have been calculated for water radon concentrations. The minimum to maximum values of dose rates were found to be 13.42-31.08 μSv y(-1). The recorded values of radon concentration in water are within the safe limit of 11 Bq l(-1) recommended by the US Environment Protection Agency [National Research Council, Risk Assessment of Radon in Drinking Water (Academy Press, Washington, DC, USA, 1999)]. All measurements were made in similar climatic and environmental conditions to ensure minimal variations in meteorological parameters. An intermediate correlation coefficient (0.5) was observed between radon exhalation rates and soil gas values.

  2. Indoor and outdoor bioaerosol levels at recreation facilities, elementary schools, and homes.

    PubMed

    Jo, Wan-Kuen; Seo, Young-Jun

    2005-12-01

    One major deficiency in linking environmental exposure to health effects is the current lack of data on environmental exposure. Therefore, to address this issue, the present study measured the bacterial and fungal concentrations in the indoor and outdoor air from two types of recreation facility (42 bars and 41 Internet cafes), 44 classrooms at 11 elementary schools, and 20 homes under uncontrolled environmental conditions during both summer and winter. No major environmental problems were reported at the four microenvironments being investigated during the entire study period. Bacteria and fungi were found in all the air samples, and the environmental occurrence of individual fungi was in the order of Cladosprium, Penicillium, Aspergillus, and Alternaria. The six parameters surveyed in the present study were all found to influence the indoor and outdoor bioaerosol levels: microenvironment type, sampling time in elementary school classrooms, agar type for measuring the fungal species, seasonal variation, facility location, and summer survey periods. The indoor and outdoor air concentrations of bacteria and fungi found in this study were comparable to those in other reports, with GM values for the total bacteria and total fungi between 10 and 10(3) colony-forming units per cubic meter of air (CFU m(-3)). The fungal concentrations found at most of the indoor environments fell within the specified guidelines of the American Conference of Government Industrial Hygienists (ACGIH), between 100 and 1000 CFU m(-3) for the total fungi. However, the indoor bioaerosol concentrations at most of the surveyed environments exceeded the Korean indoor bioaerosol guideline (800 CFU m(-3)). Consequently, the current findings suggest the need for reducing strategy for indoor microorganisms at the surveyed microenvironments.

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

    PubMed

    George, A C

    2015-11-01

    The US radon measurement programme began in the late 1950s by the US Public Health Service in Colorado, New Mexico and Utah during the uranium frenzy. After the 1967 Congressional Hearings on the working conditions in uranium mines, the US Atomic Energy Commission (AEC) was asked to conduct studies in active uranium mines to assess the exposure of the miners on the Colorado Plateau and in New Mexico. From 1967 to 1972, the Health and Safety Laboratory of the US AEC in New York investigated more than 20 uranium mines for radon and radon decay product concentrations and particle size in 4 large uranium mines in New Mexico. In 1970, the US Environmental Protection Agency (EPA) was established and took over some of the AEC radon measurement activities. Between 1975 and 1978, the Environmental Measurements Laboratory of the US Department of Energy conducted the first detailed indoor radon survey in the USA. Later in 1984, the very high concentrations of radon found in Pennsylvania homes set the wheels in motion and gave birth to the US Radon Industry. The US EPA expanded its involvement in radon issues and assumed an active role by establishing the National Radon Proficiency Program to evaluate the effectiveness of radon measurement and mitigation methods. In 1998, due to limited resources EPA privatised the radon programme. This paper presents a personal perspective of past events and current status of the US radon programme. It will present an update on radon health effects, the incidence rate of lung cancer in the USA and the number of radon measurements made from 1988 to 2013 using short-term test methods. More than 23 million measurements were made in the last 25 y and as a result more than 1.24 million homes were mitigated successfully. It is estimated that <2 % of the radon measurements performed in the USA are made using long-term testing devices. The number of homes above the US action level of 148 Bq m(-3) (4 pCi l(-1)) may be ∼8.5 million because ∼50

  4. A prediction method for radon in groundwater using GIS and multivariate statistics.

    PubMed

    Skeppström, Kirlna; Olofsson, Bo

    2006-08-31

    Radon (222Rn) in groundwater constitutes a source of natural radioactivity to indoor air. It is difficult to make predictions of radon levels in groundwater due to the heterogeneous distribution of uranium and radium, flow patterns and varying geochemical conditions. High radon concentrations in groundwater are not always associated with high uranium content in the bedrock, since groundwater with a high radon content has been found in regions with low to moderate uranium concentrations in the bedrock. This paper describes a methodology for predicting areas with high concentrations of 222Rn in groundwater on a general scale, within an area of approximately 185x145km2. The methodology is based on multivariate statistical analyses, including principal component analysis and regression analysis, and investigates the factors of geology, land use, topography and uranium (U) content in the bedrock. A statistical variable based method (the RV method) was used to estimate risk values related to different radon concentrations. The method was calibrated and tested on more than 4400 drilled wells in Stockholm County. The results showed that radon concentration was clearly correlated to bedrock type, well altitude and distance from fracture zones. The weighted index (risk value) estimated by the RV method provided a fair prediction of radon potential in groundwater on a general scale. Risk values obtained using the RV method were compared to radon measurements in 12 test areas (on a local scale, each of area 25x25km2) in Stockholm County and a high correlation (r=-0.87) was observed. The study showed that the occurrence and spread of radon in groundwater are guided by multiple factors, which can be used in a radon prediction method on a general scale. However, it does not provide any direct information on the geochemical and flow processes involved.

  5. Measurements of radon concentration levels in thermal waters in the region of Konya, Turkey.

    PubMed

    Erdogan, Mehmet; Ozdemir, Fatih; Eren, Nuretdin

    2013-01-01

    (222)Rn (radon) is one of the most important sources of natural radiation to which people are exposed. It is an alpha-emitting noble gas and it can be found in various concentrations in soil, air and in different kinds of water. In this study, we present the results of radon concentration measurements in thermal waters taken from the sources in the region of Konya located in the central part of Turkey. The radon activity concentrations in 10 thermal water samples were measured by using the AlphaGUARD PQ 2000PRO radon gas analyser in spring and summer of the year 2012. We found that radon activity concentrations range from 0.60±0.11 to 70.34±3.55 kBq m(-3) and from 0.67±0.03 to 36.53±4.68 kBq m(-3) in spring and summer, respectively. We also calculated effective doses per treatment in the spas for the spring and summer seasons. It was found that the minimum and maximum effective doses per treatment are in the range of 0.09-10.13 nSv in spring and in the range of 0.1-5.26 nSv in summer.

  6. Limited applicability of cost-effectiveness and cost-benefit analyses for the optimization of radon remedial measures.

    PubMed

    Jiránek, Martin; Rovenská, Katerina

    2010-10-15

    Ways of using different decision-aiding techniques for optimizing and evaluating radon remedial measures have been studied on a large set of data obtained from the remediation of 32 houses that had an original indoor radon level above 1000 Bq/m(3). Detailed information about radon concentrations before and after remediation, type of remedial measures and installation and operation costs were used as the input parameters for a comparison of costs and for determining the efficiencies, for a cost-benefit analysis and a cost-effectiveness analysis, in order to find out whether these criteria and techniques provide sufficient and relevant information for improving and optimizing remediation. Our study confirmed that the installation costs of remediation do not depend on the original indoor radon level, but on the technical state of the building. In addition, the study reveals that the efficiency of remediation does not depend on the installation costs. Cost-benefit analysis and cost-effectiveness analysis lead to the conclusion that remedial measures reducing the indoor radon concentration from values above 1000 Bq/m(3) are always acceptable and reasonable. On the other hand, these techniques can neither help the designer to choose the proper remedial measure nor provide information resulting in improved remediation.

  7. RADON REDUCTION AND RADON-RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK - VOLUME 2: APPENDICES

    EPA Science Inventory

    Growing concern about health risks associated with exposure to indoor radon, a radioactive gas found in varying amounts in nearly all houses, has underscored the need for dependable radon reduction methods in existing and newly constructed houses. Responding to this need, the U....

  8. 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%.

  9. Carcinogenic risk coefficients at environmental levels of radon exposures: A microdosimetric approach

    SciTech Connect

    Zaider, M.; Varma, N.

    1996-06-01

    We report a microdosimetric-based evaluation of the effects of domestic exposure to radon. The risk coefficients obtained here are based on the microdosimetry of radon progeny alpha particles, on a function q(y) for in vivo radiogenic neoplasia, and on scaling A-bomb results (epidemiology + microdosimetry) to radon exposure. We do not use miner data, nor do we invoke such notions as quality factors, dose equivalent or equivalent dose. With basal cells as targets our estimated risk coefficients are in good agreement with the miner data, and thus a quality factor of about 20 (as suggested by ICRP 60) is not unreasonable. However, if we take as targets the secretory cells our risk coefficients are twice as large as those reported by BEIR-IV. The main uncertainty in these estimates remains the dosimetric model. 35 refs., 4 figs., 2 tabs.

  10. Radon exposure at a radioactive waste storage facility.

    PubMed

    Manocchi, F H; Campos, M P; Dellamano, J C; Silva, G M

    2014-06-01

    The Waste Management Department of Nuclear and Energy Research Institute (IPEN) is responsible for the safety management of the waste generated at all internal research centers and that of other waste producers such as industry, medical facilities, and universities in Brazil. These waste materials, after treatment, are placed in an interim storage facility. Among them are (226)Ra needles used in radiotherapy, siliceous cake arising from conversion processes, and several other classes of waste from the nuclear fuel cycle, which contain Ra-226 producing (222)Rn gas daughter.In order to estimate the effective dose for workers due to radon inhalation, the radon concentration at the storage facility has been assessed within this study. Radon measurements have been carried out through the passive method with solid-state nuclear track detectors (CR-39) over a period of nine months, changing detectors every month in order to determine the long-term average levels of indoor radon concentrations. The radon concentration results, covering the period from June 2012 to March 2013, varied from 0.55 ± 0.05 to 5.19 ± 0.45 kBq m(-3). The effective dose due to (222)Rn inhalation was further assessed following ICRP Publication 65.

  11. Radon testing behavior in a sample of individuals with high home radon screening measurements

    SciTech Connect

    Field, R.W.; Kross, B.C.; Vust, L.J. )

    1993-08-01

    Although radon exposure has been identified as the second leading cause of lung cancer, fewer than 6% of US homeowners test their homes for radon. This report examines participants' follow-up radon testing behavior subsequent to receiving an initial screening radon level greater than 20 pCi/L. Sixty-two participants in the Iowa State-Wide Rural Radon Screening Survey who had radon screening measurements over 20 pCi/L were questioned by phone survey 3 months after receipt of their radon screening result to assess: whether participants were aware of radon's health risk; if participants recalled the radon screening results; how participants perceived the relative health risk of radon and whether participants planned follow-up radon testing. Only 19% of the respondents specifically identified lung cancer as the possible adverse health outcome of high radon exposure, and the majority of participants underestimated the health risks high radon levels pose when compared to cigarettes and x-rays. In addition, less than one third (29%) of the participants actually remembered their radon screening level within 10 pCi/L 3 months after receiving their screening results. Only 53% of the individuals correctly interpreted their screening radon level as being in the high range, and only 39% of the participants planned follow-up radon measurements. Receipt of radon screening test results indicating high radon levels was not an adequate motivational factor in itself to stimulate further radon assessment or mitigation. The findings suggest that free radon screening will not result in a dramatic increase in subsequent homeowner initiated remediation or further recommended radon testing. 13 refs., 1 fig., 5 tabs.

  12. 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.

  13. Radon survey and soil gamma doses in primary schools of Batman, Turkey.

    PubMed

    Damla, Nevzat; Aldemir, Kamuran

    2014-06-01

    A survey was conducted to evaluate levels of indoor radon and gamma doses in 42 primary schools located in Batman, southeastern Anatolia, Turkey. Indoor radon measurements were carried out using CR-39 solid-state nuclear track detector-based radon dosimeters. The overall mean annual (222)Rn activity in the surveyed area was found to be 49 Bq m(-3) (equivalent to an annual effective dose of 0.25 mSv). However, in one of the districts (Besiri) the maximum radon value turned out to be 307 Bq m(-3). The estimated annual effective doses are less than the recommended action level (3-10 mSv). It is found that the radon concentration decreases with increasing floor number. The concentrations of natural and artificial radioisotopes were determined using gamma-ray spectroscopy for soil samples collected in close vicinity of the studied schools. The mean gamma activity concentrations in the soil samples were 31, 25, 329 and 12 Bq kg(-1) for (226)Ra, (232)Th, (40)K and (137)Cs, respectively. The radiological parameters such as the absorbed dose rate in air and the annual effective dose equivalent were calculated. These radiological parameters were evaluated and compared with the internationally recommended values.

  14. Radon in the Gulf Coast area: Potential problem or exaggerated risk?

    SciTech Connect

    Duex, T.W.

    1994-12-31

    Indoor air pollution from radon has been identified by the U.S. Environmental Protection Agency (U.S. EPA) as a serious health problem; estimates indicate that radon is the second-leading cause of lung cancer (after smoking) and that high levels of radon may cause as many as 20,000 to 40,000 lung cancer deaths per year in the United States. Studies of the potential risk in the Gulf Coast have been few. This report summarizes more than 7,000 previously unreported radon analyses and relates them to geological information in order to identify possible problem areas for the Gulf Coast region of Louisiana, Texas, Mississippi, Alabama, and Florida. High levels of indoor radon are generally associated with older {open_quotes}crystalline{close_quotes} igneous and metamorphic bedrock. Thus, most areas of the Gulf Coast are relatively low risk because they are underlain by Cenozoic sedimentary rocks and unconsolidated deposits. However, some types of sedimentary deposits, such as {open_quotes}black shale{close_quotes} and phosphate-rich rocks, can be areas of high risk. According to the U.S. EPA indoor radon survey results the percentage of houses with screening levels greater than 4 pCi/l (picocuries per liter) for given states is as follows: AL = 6.0%; LA = 0.8%; MS = 2.0%; and TX = 4.0% (no data available for FL). The data developed in the current study indicate that the percentage of houses with greater than 4/pCi/l for given states as follows: AL = 6.1%; LA = 0.6%; MS = 2.0%; TX =1.6%; and FL = 4.5%. The areas that appear to have the greatest risk are parts of northern Alabama and Mississippi, central Texas, and some areas in Florida.

  15. Radon in the Gulf Coast area: Potential problem or exaggerated risk?

    SciTech Connect

    Duex, T.W.

    1994-09-01

    Indoor air pollution from radon has been identified by the EPA as a serious health problem; estimates indicate that radon is the second leading cause of lung cancer (after smoking) and that high levels of radon may cause as many as 20,000 to 40,000 lung cancer deaths per year in the United States. Studies of the potential risk in the Gulf Coast have been sparse. This report summarizes over 7000 previously unreported radon analyses and relates them to geological information to identify possible problem areas for the Gulf Coast region of Louisiana, Texas, Mississippi, Alabama, and Florida. High levels of indoor radon are generally associated with older {open_quotes}crystalline{close_quotes} igneous and metamorphic bedrock; thus, most areas of the Gulf Coast are of relatively low risk because they are underlain by Cenozoic sedimentary rocks and unconsolidated deposits. However, some types of sedimentary deposits, such as {open_quotes}black shale{close_quotes} and phosphate-rich rocks, can underlie areas of high risk. According to EPA indoor radon survey results the percentage of houses with screening levels greater than 4 pCi/1 (picocuries per liter) for given states is as follows: Alabama = 0.6%, Louisiana = 0.8%, Mississippi = 2.0%, and Texas = 4.0% (no data available for Florida). The data presented here for the percentage of houses with greater than 4 pCi/1 for given states is as follows: Alabama = 6.1 %, Louisiana = 0.6%, Mississippi = 2.0%, Texas = 1.6%, and Florida = 4.5%. The areas that appear to have the greatest risk are parts of northern Alabama and Mississippi, central Texas, and some areas in Florida.

  16. 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

  17. Relationships between estimated flame retardant emissions and levels in indoor air and house dust.

    PubMed

    Liagkouridis, I; Cequier, E; Lazarov, B; Palm Cousins, A; Thomsen, C; Stranger, M; Cousins, I T

    2016-09-10

    A significant number of consumer goods and building materials can act as emission sources of flame retardants (FRs) in the indoor environment. We investigate the relationship between the emission source strength and the levels of 19 brominated flame retardants (BFRs) and seven organophosphate flame retardants (OPFRs) in air and dust collected in 38 indoor microenvironments in Norway. We use modeling methods to back-calculate emission rates from indoor air and dust measurements and identify possible indications of an emission-to-dust pathway. Experimentally based emission estimates provide a satisfactory indication of the relative emission strength of indoor sources. Modeling results indicate an up to two orders of magnitude enhanced emission strength for OPFRs (median emission rates of 0.083 and 0.41 μg h(-1) for air-based and dust-based estimates) compared to BFRs (0.52 and 0.37 ng h(-1) median emission rates). A consistent emission-to-dust signal, defined as higher dust-based than air-based emission estimates, was identified for four of the seven OPFRs, but only for one of the 19 BFRs. It is concluded, however, that uncertainty in model input parameters could potentially lead to the false identification of an emission-to-dust signal.

  18. Exploring the consequences of climate change for indoor air quality

    NASA Astrophysics Data System (ADS)

    Nazaroff, William W.

    2013-03-01

    Climate change will affect the concentrations of air pollutants in buildings. The resulting shifts in human exposure may influence public health. Changes can be anticipated because of altered outdoor pollution and also owing to changes in buildings effected in response to changing climate. Three classes of factors govern indoor pollutant levels in occupied spaces: (a) properties of pollutants; (b) building factors, such as the ventilation rate; and (c) occupant behavior. Diversity of indoor conditions influences the public health significance of climate change. Potentially vulnerable subpopulations include not only the young and the infirm but also those who lack resources to respond effectively to changing conditions. Indoor air pollutant levels reflect the sum of contributions from indoor sources and from outdoor pollutants that enter with ventilation air. Pollutant classes with important indoor sources include the byproducts of combustion, radon, and volatile and semivolatile organic compounds. Outdoor pollutants of special concern include particulate matter and ozone. To ensure good indoor air quality it is important first to avoid high indoor emission rates for all pollutants and second to ensure adequate ventilation. A third factor is the use of air filtration or air cleaning to achieve further improvements where warranted. Reprinted with permission from Climate Change, the Indoor Environment, and Health (2011) by the National Academy of Sciences, Courtesy of the National Academies Press, Washington, DC.

  19. Indoor mold levels and current asthma among school-aged children in Saskatchewan, Canada.

    PubMed

    Oluwole, O; Kirychuk, S P; Lawson, J A; Karunanayake, C; Cockcroft, D W; Willson, P J; Senthilselvan, A; Rennie, D C

    2017-03-01

    Current knowledge regarding the association between indoor mold exposures and asthma is still limited. The objective of this case-control study was to investigate the relationship between objectively measured indoor mold levels and current asthma among school-aged children. Parents completed a questionnaire survey of health history and home environmental conditions. Asthma cases had a history of doctor-diagnosed asthma or current wheeze without a cold in the past 12 months. Controls were age- and sex-matched to cases. Vacuumed dust samples were collected from the child's indoor play area and mattress. Samples were assessed for mold levels and quantified in colony-forming units (CFU). Sensitization to mold allergens was also determined by skin testing. Being a case was associated with family history of asthma, pet ownership, and mold allergy. Mold levels (CFU/m(2) ) in the dust samples of children's mattress and play area floors were moderately correlated (r = 0.56; P < 0.05). High mold levels (≥30 000 CFU/m(2) ) in dust samples from play [adjusted odds ratio (aOR) = 2.6; 95% CI: 1.03-6.43] and mattress (aOR) = 3.0; 95% CI: 1.11-8.00) areas were significantly associated with current asthma. In this study high levels of mold are a risk factor for asthma in children.

  20. Emanation of radon from household granite.

    PubMed

    Kitto, Michael E; Haines, Douglas K; Arauzo, Hernando Diaz

    2009-04-01

    Emanation of radon (222Rn) from granite used for countertops and mantels was measured with continuous and integrating radon monitors. Each of the 24 granite samples emitted a measurable amount of radon. Of the two analytical methods that utilized electret-based detectors, one measured the flux of radon from the granite surfaces, and the other one measured radon levels in a glass jar containing granite cores. Additional methods that were applied utilized alpha-scintillation cells and a continuous radon monitor. Measured radon flux from the granites ranged from 2 to 310 mBq m-2 s-1, with most granites emitting <20 mBq m-2 s-1. Emanation of radon from granites encapsulated in airtight containers produced equilibrium concentrations ranging from <0.01 to 11 Bq kg-1 when alpha-scintillation cells were used, and from <0.01 to 4.0 Bq kg-1 when the continuous radon monitor was used.

  1. Sources and Levels of PCBs in Indoor Environments

    EPA Science Inventory

    Source assessment• Primary sources – caulk and light ballasts (6 schools)• Secondary sources – paint, tile, furnishings, etc. (3 schools)• Emission rate estimation Environmental levels (6 schools except dust)• Air, surface, dust, soil PCB c...

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

    PubMed

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

    2015-12-01

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

  3. Variation in the radon concentrations and outdoor gamma radiation levels in relation to different geological formations in the thermal regions of Bursa, Turkey.

    PubMed

    Akkaya, Gizem; Kahraman, Ayşegül; Koray, Abdullah; Kaynak, Gökay

    2016-09-01

    Spring waters used as spas and their region may contain significant amounts of natural radionuclides. The main sources of exposure are the inhalation of radon and its decay products released from the water and soil and terrestrial gamma-radiation. In order to evaluate the potential risk of thermal regions in Bursa, located in the impact area of the NAF (North Anatolian Fault), radon and thoron concentrations in soil gas, radon concentrations in thermal waters and outdoor gamma radiation levels were measured in thermal regions that have different geological formations. The radon and thoron concentrations in soil-gas were found to vary from 2272  ±  121 to 245196  ±  3455 Bq m(-3) and from 999  ±  218 to 178 848  ±  17 742 Bq m(-3), respectively. The radon concentrations in thermal waters ranged from 0.99  ±  0.21 to 226.74  ±  2.51 Bq l(-1) in the rainy season and from 0.26  ±  0.10 to 178.03  ±  12.86 Bq l(-1) in the dry season. The measured outdoor gamma radiation levels varied from 38 to 180 nGy h(-1). The gamma dose rates were found to be strong positively correlating with the radon and thoron concentrations in soil-gas. The radon and outdoor gamma radiation levels were observed to be a function of the geological formations of the area.

  4. 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.

  5. Uranium distribution and radon exhalation from Brazilian dimension stones.

    PubMed

    Amaral, P G Q; Galembeck, T M B; Bonotto, D M; Artur, A C

    2012-04-01

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

  6. Statistical analysis of the radon-222 potential of rocks in Virginia, U.S.A.

    USGS Publications Warehouse

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

    1992-01-01

    More than 3,200 indoor radon-222 (222Rn) measurements were made seasonally in an area of about 1,000 square kilometers of the Coastal Plain and Piedmont physiographic provinces in Virginia, U.S.A. Results of these measurements indicate that some geological units are associated, on the average, with twice as much indoor222Rn as other geological units, and that indoor222Rn varies seasonally. The Kruskal-Wallis test was used to test whether indoor222Rn concentrations for data gathered over the winter and summer seasons differ significantly by rock unit. The tests concluded that indoor222Rn concentrations for different rock units were not equal at the 5-percent significance level. The rocks associated with the highest median indoor222Rn concentration are specific rocks in the Mesozoic Culpeper basin, including shale and siltstone units with Jurassic diabase intrusives, and mica schists in the Piedmont physiographic province. The pre-Triassic Peters Creek Schist has the highest ranking in terms of indoor222Rn concentration. The rocks associated with the lowest indoor222Rn concentrations include coastal plain sediments, the Occoquan Granite, Falls Church Tonalite, Piney Branch Mafic and Ultramafic complex, and unnamed mafic and ultramafic inclusions, respectively. The rocks have been ranked according to observed222Rn concentration by transforming the average rank of indoor222Rn concentrations to z scores. ?? 1992 Springer-Verlag New York Inc.

  7. Measurement and determination of radon source potential: A literature review

    SciTech Connect

    Tanner, A.B.

    1994-04-01

    Radon source potential may be estimated for areas of a nation, state, county, housing development, or building lot. The critical characteristics of the soil are its radium concentration, emanation coefficient, permeability to gas, and diffusion coefficient for radon under typical conditions. This report summarizes and evaluates available information on radon potential mapping and site-specific characterization. More than 100 reports have been found that bear on radon potential mapping, and indicate fair to good agreement with indoor radon results where correlations have been possible.

  8. Radon remediation and prevention status in 23 European countries.

    PubMed

    Holmgren, O; Arvela, H; Collignan, B; Jiránek, M; Ringer, W

    2013-12-01

    Radon remediation and prevention aim at reducing indoor radon concentrations in the existing and new buildings. This paper gives an estimate of the number of dwellings where remediation or preventive measures have been applied so far in Europe. Questionnaires were sent to contact persons in national radiation protection authorities and radon-related research institutes. Answers from 23 European countries were obtained. Approximately 26 000 dwellings have been remediated in total. Millions of dwellings remain to be remediated and the number is increasing due to the rare use of radon prevention. These facts imply a need for an efficient radon strategy to promote radon remediation. Moreover, the importance of radon prevention in new construction and the regulations concerning radon in the national building codes should be emphasised.

  9. 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.

  10. Association between State Assistance on the Topic of Indoor Air Quality and School District-Level Policies That Promote Indoor Air Quality in Schools

    ERIC Educational Resources Information Center

    Everett Jones, Sherry; Doroski, Brenda; Glick, Sherry

    2015-01-01

    Nationally representative data from the 2012 School Health Policies and Practices Study examined whether state assistance on indoor air quality (IAQ) was associated with district-level policies and practices related to IAQ and integrated pest management (IPM). Districts in states that provided assistance on IAQ were more likely than districts not…

  11. Regional and Detailed Survey for Radon Activities in Soil-Gas and Groundwater in the Okchon Zone, Korea

    NASA Astrophysics Data System (ADS)

    Je, H.-K.; Chon, H.-T.

    2012-04-01

    The Okchon zone in Korea provides a typical example of natural geological materials enriched in potentially toxic elements including uranium which is parent nuclide for radon gas. For the purpose of radon radioactivity risk assessment, making the map of radon risk grade from Okchon zone, regional and detailed field surveys were carried out during 3 years. The study area is located in the central part of Korea, called the Okchon zone (about 5,100 km2), which occur in a 80km wide, northeast-trending belt that extends across the Korean Peninsula. The Okchon zone is underlain by metasedimentary rocks of unknown age that are composed mainly of black slate, phyllite, shale, and limestone. The three research areas (defined as Boeun, Chungju, and Nonsan) for detailed survey were selected from the results of regional survey. Results of detailed radon survey indicated a wide range of radon activities for soil-gases (148-1,843 pCi/L) and ground waters (23-5,540 pCi/L). About 15 percent of soil-gas samples exceeded 1,000 pCi/L and 84 percent of ground water samples exceeded the MCL (maximum contaminant level) of drinking water, 300 pCi/L, which proposed by U.S. Environmental Protection Agency in 1999. For detailed survey, radon activities of soil-gas and ground water were classified as bedrock geology, based on 1/50,000 geological map and field research. For soil-gas measurements, mean values of radon activity from black slate-shale (789 pCi/L) were highest among the other base rocks. And for groundwater measurements, mean value of radon activities were decreased in the order of granite (1,345 pCi/L) > black shale-slate (915 pCi/L) > metasediments (617 pCi/L). Result of indoor radon measurement from detailed survey areas showed that about 50% of houses exceeded the indoor guideline, 4 pCi/L. For the radon risk assessment in indoor environment showed that probability of lung cancer risk from the houses located on the granite base rock (3.0×10-2) was highest among the other

  12. Reducing Radon in Schools: A Team Approach.

    ERIC Educational Resources Information Center

    Ligman, Bryan K.; Fisher, Eugene J.

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

  13. Publications about Indoor Air Quality in Schools

    EPA Pesticide Factsheets

    Publications and resources that relate to indoor air quality in schools, and design tools for schools. These publications cover a wide range of issues, including IAQ management, student performance, asthma, mold and moisture, and radon.

  14. Integrated Field-Scale, Lab-Scale, and Modeling Studies for Improving the Ability to Assess the Groundwater to Indoor Air Pathway at Chlorinated Solvent-Impacted Groundwater Sites

    DTIC Science & Technology

    2012-08-01

    Monitoring of Indoor Air Radon Concentrations with Time .................................14 Radon Concentrations in Soil Gas... Radon soil gas concentration contours [pCi/L] ...........................................................15 Figure 13. SF6 in indoor air with a constant...calibrations ect. August 2010- present* *SF6 started in December 2010, Radon started in February 2011 All available soil gas and

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

    PubMed

    Frutos Vázquez, Borja; Olaya Adán, Manuel; Quindós Poncela, Luis Santiago; Sainz Fernandez, Carlos; Fuente Merino, Ismael

    2011-04-01

    The present paper discusses the results of an empirical study of four approaches to reducing indoor radon concentrations based on depressurization techniques in underground sumps. The experiments were conducted in prototype housing built in an area of Spain where the average radon concentration at a depth of 1 m is 250 kBq m(-3). Sump effectiveness was analysed in two locations: underneath the basement, which involved cutting openings into the foundation, ground storey and roof slabs, and outside the basement walls, which entailed digging a pit alongside the building exterior. The effectiveness of both sumps was likewise tested with passive and forced ventilation methods. The systems proved to be highly efficient, lowering radon levels by 91-99%, except in the solution involving passive ventilation and the outside sump, where radon levels were reduced by 53-55%. At wind speeds of over 8 m/s, however, passive ventilation across an outside sump lowered radon levels by 95% due to a Venturi effect induced drop in pressure.

  16. Radon Prevention in the Design and Construction of Schools and Other Large Buildings.

    ERIC Educational Resources Information Center

    Leovic, Kelly W.; Craig, A. B.

    Radon is a naturally occurring radioactive gas in ambient air that is estimated to cause thousands of deaths from lung cancer each year. This report outlines ways in which to ameliorate the presence of radon in schools buildings. The first section is a general introduction for those who need background information on the indoor radon problem and…

  17. Spatial and temporal variation in factors governing the radon source potential of soil

    SciTech Connect

    Sextro, R.G.; Nazaroff, W.W.; Turk, B.H.

    1988-10-01

    Soil is the predominant source of radon in most US homes, particularly for those homes with elevated indoor concentrations. Three factors help govern the indoor radon concentration, the radon production rate in the soil, the air permeability of the soil surrounding the building substructure, and the coupling between the soil and the building. In order to evaluate the spatial and temporal variability of the first two factors, soil permeabilities and soil gas radon concentrations have been measured at different locations and as a function of time. The spatial variability in permeability measurements at an individual homesite was seen to range from approximately a factor of ten to more than four orders of magnitude. Similarly, spatial variations in soil gas radon concentrations are less than a factor of two at some homesites to a factor of /approximately/200 at others. The temporal changes in permeability and soil gas radon at a given sampling location are somewhat smaller, yielding variations ranging from less than a factor of two to a factor of /approximately/90 in the case of permeability, and from less than a factor of three to a factor of /approximately/40 for soil gas radon concentrations. A method of combining measurements of soil gas radon and air permeability to provide a characteristic parameter -- the radon source potential -- has been developed and is briefly reviewed. Calculated indoor radon concentrations, based on measured values of radon source potential at a few sample homesites, correlate with the measured indoor radon concentrations. 8 refs., 4 figs., 3 tabs.

  18. Are Neighborhood-Level Characteristics Associated with Indoor Allergens in the Household?

    PubMed Central

    Rosenfeld, Lindsay; Rudd, Rima; Chew, Ginger L.; Emmons, Karen; Acevedo-García, Dolores

    2010-01-01

    Background Individual home characteristics have been associated with indoor allergen exposure; however, the influence of neighborhood-level characteristics has not been well-studied. We defined neighborhoods as community districts determined by the New York Department of City Planning. Objective We examined the relationship between neighborhood-level characteristics and the presence of dust mite (Der f 1), cat (Fel d 1), cockroach (Bla g 2), and mouse (MUP) allergens in the household. Methods Using data from the Puerto Rican Asthma Project, a birth cohort of Puerto Rican children at risk of allergic sensitization (n=261) we examined associations between neighborhood characteristics (percent tree canopy, asthma hospitalizations per 1000 children, roadway length within 100 meters of buildings, serious housing code violations per 1000 rental units, poverty rates, and felony crime rates) and the presence of indoor allergens. Allergen cutpoints were used for categorical analyses and defined as follows: dust mite: >0.25 μg/g; cat: >1 μg/g; cockroach: >1 U/g; mouse: >1.6 μg/g. Results Serious housing code violations were statistically significantly positively associated with dust mite, cat and mouse allergens (continuous variables), adjusting for mother's income and education, and all neighborhood-level characteristics. In multivariable logistic regression analyses, medium levels of housing code violations were associated with higher dust mite and cat allergens (1.81, 95%CI: 1.08, 3.03 and 3.10, 95%CI: 1.22, 7.92, respectively). A high level of serious housing code violations was associated with higher mouse allergen (2.04, 95%CI: 1.15, 3.62). A medium level of housing code violations was associated with higher cockroach allergen (3.30, 95%CI: 1.11, 9.78). Conclusions Neighborhood-level characteristics, specifically housing code violations, appear to be related to indoor allergens, which may have implications for future research explorations and policy decisions. PMID

  19. Researching Radon.

    ERIC Educational Resources Information Center

    Lucidi, Louis; Mecca, Peter M.

    2001-01-01

    Introduces a project in which students examined the physics, chemistry, and geology of radon and used available technology to measure radon concentrations in their homes. Uses the inquiry process, analytical skills, communication skills, content knowledge, and production of authentic products for student assessment. (YDS)

  20. Indoor air pollution levels in public buildings in Thailand and exposure assessment.

    PubMed

    Klinmalee, Aungsiri; Srimongkol, Kasama; Kim Oanh, Nguyen Thi

    2009-09-01

    Levels of pollutants including PM2.5 and PM2.5 composition (black carbon and water soluble ions), SO(2), NO(2), CO, CO(2), and BTEX (benzene, toluene, ethylbenzene, xylene) were monitored for indoor and outdoor air at a university campus and a shopping center, both located in the Northern suburb of Bangkok. Sampling was done during December 2005-February 2006 on both weekdays and weekends. At the university, indoor monitoring was done in two different air conditioned classrooms which shows the I/O ratios for all pollutants to be below 0.5-0.8 during the weekends. However, on weekdays the ratios for CO(2) and most detected BTEX were above 1.0. The concept of classroom occupancy was defined using a function of the student number in a lecture hour and the number of lecture hours per day. Classroom 2, which had a higher occupancy than classroom 1, was characterized by higher concentrations of most pollutants. PM2.5 was an exception and was higher in classroom 1 (37 microg/m(3), weekdays) as compared to classroom 2 (26 microg/m(3), weekdays) which was likely linked to the dust resuspension from the carpeted floor in the former. Monitoring was also done in the shopping mall at three different sites. Indoor pollutants levels and the I/O ratios at the shopping mall were higher than at the university. Levels of all pollutants measured at the car park, except for toluene and CO(2), were the highest. I/O ratios of the pollutants at the mall were above 1.0, which indicates the relatively higher influence of the indoor sources. However, the black carbon content in PM2.5 outdoor is higher than indoor, which suggest the important contribution from outdoor combustion sources such as the traffic. Major sources of outdoor air pollution in the areas were briefly discussed. Exposure modeling was applied using the time activity and measured pollutant concentrations to assess the exposure of different groups of people in the study areas. High exposure to PM2.5, especially for the people

  1. Radon Assessment of Occupational Facilities, Homestead ARB, FL

    DTIC Science & Technology

    2013-11-21

    Consultative Letter 3. DATES COVERED (From – To) May 2013 – August 2013 4. TITLE AND SUBTITLE Radon Assessment of Occupational Facilities...unlimited. Case Number: 88ABW-2013-4919, 21 Nov 2013 13. SUPPLEMENTARY NOTES 14. ABSTRACT An assessment of indoor radon concentrations was...established in AFI 48-148 for long-term monitoring. Historical results indicate a radon risk characterization category of “medium,” requiring all

  2. 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.

  3. Radon in ground water supplies

    SciTech Connect

    Dixon, K.L.; Lee, R.G.

    1989-06-01

    In September 1986, the System Water Quality Department of the American Water Works Service Co. began conducting a radon survey that was designed to determine the levels of radon in American ground water supplies, and to assess the radon removal efficiency of existing treatment processes such as filtration through granular activated carbon (GAC) and various forms of aeration. The survey found that companies in the northeastern part of the country experienced the highest levels of radon in ground water supplies. The highest concentrations were in individual wells in New Hampshire, Maryland, Connecticut, Rhode Island, New Jersey, Pennsylvania and California. The analytical results from the occurrence phase of the survey seemed to correlate well with the known geology of the aquifer materials from which samples of ground water were drawn. The highest levels were associated with formations of uranium-bearing granitic rocks. GAC can effectively reduce radon concentrations in drinking water supplies to very low levels. However, the amount of contact time within the carbon bed required to do so would be prohibitive to many water utilities from an operational and economic standpoint. Further, disposal of the spent GAC as a low-level radioactive waste may be required. Aeration is very effective in the removal of radon from drinking water. Packed tower aerators achieved > 95% reduction in radon concentrations and conventional cascading tray aerators achieved > 75% reduction in radon concentrations. 7 refs., 6 tabs.

  4. Radon: implications for the health professional

    SciTech Connect

    Romano, C.A.

    1990-01-01

    Radon is a colorless, odorless gas formed by radioactive decay of radium and uranium, which are naturally present in the earth's crust. When concentrated indoors, this invisible gas becomes a potential health hazard. The Environmental Protection Agency estimates that up to 20,000 lung cancer deaths annually can be attributed to prolonged radon exposure. Radon is an important health issue that should be understood by all health care professionals. This paper discusses some of the important issues regarding radon, such as the incidences of lung cancer believed to be attributable to radon, the high-risk areas in the United States, federal safety guidelines, and public apathy. These issues and their impact on the health care required by professionals, especially nurse practitioners, are discussed.

  5. Radon in ground water of the Lower Susqehanna and Potomac River basins

    USGS Publications Warehouse

    Lindsey, Bruce D.; Ator, Scott W.

    1996-01-01

    Ground-water samples collected from 267 wells were analyzed for radon as part of a water-quality reconnaissance of subunits of the Lower Susquehanna and Potomac River Basins conducted by the United States Geological Survey (USGS) as part of the National Water-Quality Assessment (NAWQA) program. Radon is a product of the radioactive decay of uranium. Airborne radon has been cited by the Surgeon General of the United States as the second-leading cause of lung cancer and the United States Environmental Protection Agency (USEPA) has identified ground-water supplies as possible contributing sources of indoor radon. Eighty percent of ground-water samples collected for this study were found to contain radon at activities greater than 300 pCi/L (picocuries per liter), the USEPA's proposed Maximum Contaminant Level for radon in drinking water, and 31 percent of samples contained radon at activities greater than 1,000 pCi/L. The 10 subunits where samples were collected were grouped into three classes - median ground-water radon activity less than 300 pCi/L, between 300 pCi/L and 1,000 pCi/L, and greater than 1,000 pCi/L. Subunits underlain by igneous and metamorphic rocks of the Piedmont Physiographic Province typically have the highest median ground-water radon activities (greater than 1,000 pCi/L); although there is a large variation in radon activities within most of the subunits. Lower median radon activities (between 300 pCi/L and 1,000 pCi/L) were found in ground water in subunits underlain by limestone and dolomite. Of three subunits underlain by sandstone and shale, one fell into each of the three radon-activity classes. The large variability within these subunits may be attributed to the fact that the uranium content of sandstone and shale is related to the uranium content of the sediments from which they formed.

  6. Simplified modeling for infiltration and radon entry

    SciTech Connect

    Sherman, M.H.

    1992-08-01

    Air leakage in the envelopes of residential buildings is the primary mechanism for provided ventilation to those buildings. For radon the same mechanisms that drive the ventilation, drive the radon entry This paper attempts to provide a simplified physical model that can be used to understand the interactions between the building leakage distribution, the forces that drive infiltration and ventilation, and indoor radon concentrations, Combining both ventilation and entry modeling together allows an estimation of Radon concentration and exposure to be made and demonstrates how changes in the envelope or ventilation system would affect it. This paper will develop simplified modeling approaches for estimating both ventilation rate and radon entry rate based on the air tightness of the envelope and the driving forces. These approaches will use conventional leakage values (i.e. effective leakage area ) to quantify the air tightness and include natural and mechanical driving forces. This paper will introduce a simplified parameter, the Radon Leakage Area, that quantifies the resistance to radon entry. To be practical for dwellings, modeling of the occupant exposures to indoor pollutants must be simple to use and not require unreasonable input data. This paper presents the derivation of the simplified physical model, and applies that model to representative situations to explore the tendencies to be expected under different circumstances.

  7. [Indoor Deposition Flux, Seasonal Variations and Human Exposure Levels of Polybrominated Diphenyl Ethers in Xiamen, China].

    PubMed

    Han, Wen-liang; Liu, Yu; Chen, Hai-ming; Chen, Xing-tong; Fan, Tao

    2016-03-15

    Indoor dust was an important and even a major route of human exposure to polybrominated diphenyl ethers (PBDEs). However, the vacuum dust concentrations were less correlated with indoor residents' serum concentrations of PBDEs, thus inadequat for either estimation of human exposure dose or research of deposition flux and its seasonal variations. Passive sampling of indoo dustfall could offset these shortages. A total of 49 indoor sampling sites including homes, offices, computer rooms and furniture factor were selected in Xiamen, China to collect the four season dustfall samples with glass plates (walled by clean aluminum foil). Deposition flux, concentrations, congener profiles, seasonal variations, and human exposure to PBDEs in the dustfall were studied The geometric means of the yearly round deposition flux of ∑ PBDEs (sum of 16 BDE congeners including BDE-209) in homes offices, computer rooms and furniture factory were 6.1, 3.0, 1.1 and 179.8 ng · (m² · d)⁻¹, respectively. The geometric mea deposition flux of ∑ PBDEs in homes was 2 times of that in offices, but the concentration of ∑ PBDEs in the dustfall from home (445.5 ng · g⁻¹) was only slightly higher than that of offices (384.0 ng · g⁻¹). The ∑ PBDEs deposition flux in homes, offices and computer rooms in Xiamen were at lower level compared with other cities around the world. The PBDEs deposition flux in furnitur factory was much higher than that in the ordinary indoor environment. Autumn was the season with highest deposition flux of ∑ PBDEs. Geometric means of BDE- 209's proportion of the ∑ PBDEs in dustfall in all seasons in the four types of indoo environment were above 80% . The deposition flux of PBDEs was correlated to the dustfall deposition flux in homes, offices and computer rooms, but not that in furniture factory. ∑₁₅ PBDEs in homes and offices were significantly correlated with the age of computers, but not quantities of electrical and electronic products

  8. Simulation of background from low-level tritium and radon emanation in the KATRIN spectrometers

    SciTech Connect

    Leiber, B.; Collaboration: KATRIN Collaboration

    2013-08-08

    The KArlsruhe TRItium Neutrino (KATRIN) experiment is a large-scale experiment for the model independent determination of the mass of electron anti-neutrinos with a sensitivity of 200 meV/c{sup 2}. It investigates the kinematics of electrons from tritium beta decay close to the endpoint of the energy spectrum at 18.6 keV. To achieve a good signal to background ratio at the endpoint, a low background rate below 10{sup −2} counts per second is required. The KATRIN setup thus consists of a high luminosity windowless gaseous tritium source (WGTS), a magnetic electron transport system with differential and cryogenic pumping for tritium retention, and electro-static retarding spectrometers (pre-spectrometer and main spectrometer) for energy analysis, followed by a segmented detector system for counting transmitted beta-electrons. A major source of background comes from magnetically trapped electrons in the main spectrometer (vacuum vessel: 1240 m{sup 3}, 10{sup −11} mbar) produced by nuclear decays in the magnetic flux tube of the spectrometer. Major contributions are expected from short-lived radon isotopes and tritium. Primary electrons, originating from these decays, can be trapped for hours, until having lost almost all their energy through inelastic scattering on residual gas particles. Depending on the initial energy of the primary electron, up to hundreds of low energetic secondary electrons can be produced. Leaving the spectrometer, these electrons will contribute to the background rate. This contribution describes results from simulations for the various background sources. Decays of {sup 219}Rn, emanating from the main vacuum pump, and tritium from the WGTS that reaches the spectrometers are expected to account for most of the background. As a result of the radon alpha decay, electrons are emitted through various processes, such as shake-off, internal conversion and the Auger deexcitations. The corresponding simulations were done using the KASSIOPEIA

  9. Indoor air and human health: major indoor air pollutants and their health implications

    SciTech Connect

    Not Available

    1984-01-01

    This publication is a collection of abstracts of papers presented at the Indoor Air and Human Health symposium. Session titles include: Radon, Microorganisms, Passive Cigarette Smoke, Combustion Products, Organics, and Panel and Audience Discussion.

  10. Environmental radon and cancer correlations in Maine.

    PubMed

    Hess, C T; Weiffenbach, C V; Norton, S A

    1983-08-01

    The distribution of 222Rn has been measured in the sixteen counties of Maine, U.S.A. by liquid scintillation counting of water samples from more than two thousand public and private wells. Three hundred and fifty of these wells have been characterized for geology and hydrology. Airborne radon has been measured in seventy houses with grab samples and in eighteen houses for 5-7 days each with continuously recording diffusion-electrostatic radon detectors. Concentrations of radon in water ranged from 20 to 180,000 pCi/l. Granite areas yielded the highest average levels (mean = 22,100 pCi/l.; n = 136), with considerable intra-granite variation. Metasedimentary rocks yielded levels characteristic of the lithology for metamorphic grades ranging from chlorite to andalusite. Sillimanite and higher-grade rocks yielded higher 222Rn levels, probably due to the intrusion of uranium-bearing pegmatites in these terranes. Airborne 222Rn in homes ranged from 0.05 to 210 pCi/l. At the high end of this range, doses will exceed recommended industrial limits. In some homes only a small fraction of the airborne 222Rn was due to the water supply. Average 222Rn levels in domestic water supplies for each of the 16 counties, calculated by areally averaging rock types and their associated 222Rn levels, were found to be significantly correlated with rates for all cancers combined and rates for lung and reproductive cancers in the counties. Although numerous factors other than cancer induction by indoor daughter exposures may be responsible for the observed correlations, these have not been investigated in detail.

  11. Quantification of ozone levels in indoor environments generated by ionization and ozonolysis air purifiers.

    PubMed

    Britigan, Nicole; Alshawa, Ahmad; Nizkorodov, Sergey A

    2006-05-01

    Indoor air purifiers are advertised as safe household products for health-conscious individuals, especially for those suffering from allergies and asthma. However, certain air purifiers produce ozone (O3) during operation, either intentionally or as a byproduct of air ionization. This is a serious concern, because O3 is a criteria air pollutant regulated by health-related federal and state standards. Several types of air purifiers were tested for their ability to produce ozone in various indoor environments at 40-50% relative humidity, including office rooms, bathrooms, bedrooms, and cars. O3 levels generated by personal wearable air purifiers were also tested. In many cases, O3 concentrations were well in excess of public and/or industrial safety levels established by U.S. Environmental Protection Agency, California Air Resources Board, and Occupational Safety and Health Administration. Simple kinetic equations were obtained that can predict the steady-state level of O3 in a room from the O3 emission rate of the air purifier and the first-order decay rate of O3 in the room. The additivity of O3 levels generated by independent O3 generators was experimentally demonstrated.

  12. Combination of geological data and radon survey results for radon mapping.

    PubMed

    Zhukovsky, Michael; Yarmoshenko, Ilia; Kiselev, Sergey

    2012-10-01

    The typical method of radon mapping usually used in most countries is the presenting of average radon concentrations in dwellings for districts or regions. Sometimes the maps of radon concentrations in the soil or maps of percentage above the reference level also demonstrated. Such approach not always can be used for identification of the regions with high probability of radon exposure above the reference levels where the population density is low. The combination of archive geological data and the results of representative radon survey allow estimating the typical parameters of radon concentration distribution for selected categories of buildings (multi-storey or rural type houses) situated in geological zones with the different radon potential. In this case it is possible to give grounds for the necessary level of radon protection measures in the new buildings constructed in this region. The use of such approach in Ural region of Russia is demonstrated.

  13. 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.

  14. Results of simultaneous radon and thoron measurements in 33 metropolitan areas of Canada

    PubMed Central

    Chen, Jing; Bergman, Lauren; Falcomer, Renato; Whyte, Jeff

    2015-01-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. 222Rn (radon gas) and 220Rn (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. PMID:24748485

  15. Long-term measurements of radon, thoron and their airborne progeny in 25 schools in Republic of Srpska.

    PubMed

    Ćurguz, Z; Stojanovska, Z; Žunić, Z S; Kolarž, P; Ischikawa, T; Omori, Y; Mishra, R; Sapra, B K; Vaupotič, J; Ujić, P; Bossew, P

    2015-10-01

    This article reports results of the first investigations on indoor radon, thoron and their decay products concentration in 25 primary schools of Banja Luka, capital city of Republic Srpska. The measurements have been carried out in the period from May 2011 to April 2012 using 3 types of commercially available nuclear track detectors, named: long-term radon monitor (GAMMA 1)- for radon concentration measurements (C(Rn)); radon-thoron discriminative monitor (RADUET) for thoron concentration measurements (C(Tn)); while equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) measured by Direct Radon Progeny Sensors/Direct Thoron Progeny Sensors (DRPS/DTPS) were exposed in the period November 2011 to April 2012. In each school the detectors were deployed at 10 cm distance from the wall. The obtained geometric mean concentrations were C(Rn) = 99 Bq m(-3) and C(Tn) = 51 Bq m(-3) for radon and thoron gases respectively. Those for equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) were 11.2 Bq m(-3) and 0.4 Bq m(-3), respectively. The correlation analyses showed weak relation only between C(Rn) and C(Tn) as well as between C(Tn) and EETC. The influence of the school geographical locations and factors linked to buildings characteristic in relation to measured concentrations were tested. The geographical location and floor level significantly influence C(Rn) while C(Tn) depend only from building materials (ANOVA, p ≤ 0.05). The obtained geometric mean values of the equilibrium factors were 0.123 for radon and 0.008 for thoron.

  16. Effects of vegetation on radon transport processes in soil

    SciTech Connect

    Borak, T.B.

    1991-01-01

    This research was conducted to measure radon concentrations. Radon concentrations in soil gas were measured on a weekly schedule. Samples were extracted through the tubes used for measuring pressure differentials at depths of 30, 100, 180 cm. The average soil moisture content was measured with the neutron gauge. Other soil parameters such as soil temperature and meteorological data were analyzed in order to determine their influence on soil radon concentrations. For indoor radon concentrations, 15 minute measurements were used to obtain a monthly average for one structure from January 1989--August 1990. Also measured were wind speed and pressure differential correlations with radon concentration. The salient features of the data obtained thus far are as follows: radon gas concentrations in the silty clay surrounding the structures increased with depth; monthly averaged radon concentrations in the underground structures do not exhibit obvious seasonal variations; indoor radon concentrations are not correlation with pressure differences between the structure and surrounding soil; for these structures the radon entry rate has two components; one that is constant and the other that changes with time; and the wind speeds that increase the radon entry rate, also increase the ventilation rate. 11 figs.

  17. Indoor air quality in Portuguese schools: levels and sources of pollutants.

    PubMed

    Madureira, J; Paciência, I; Pereira, C; Teixeira, J P; Fernandes, E de O

    2016-08-01

    Indoor air quality (IAQ) parameters in 73 primary classrooms in Porto were examined for the purpose of assessing levels of volatile organic compounds (VOCs), aldehydes, particulate matter, ventilation rates and bioaerosols within and between schools, and potential sources. Levels of VOCs, aldehydes, PM2.5 , PM10 , bacteria and fungi, carbon dioxide (CO2 ), carbon monoxide, temperature and relative humidity were measured indoors and outdoors and a walkthrough survey was performed concurrently. Ventilation rates were derived from CO2 and occupancy data. Concentrations of CO2 exceeding 1000 ppm were often encountered, indicating poor ventilation. Most VOCs had low concentrations (median of individual species <5 μg/m(3) ) and were below the respective WHO guidelines. Concentrations of particulate matter and culturable bacteria were frequently higher than guidelines/reference values. The variability of VOCs, aldehydes, bioaerosol concentrations, and CO2 levels between schools exceeded the variability within schools. These findings indicate that IAQ problems may persist in classrooms where pollutant sources exist and classrooms are poorly ventilated; source control strategies (related to building location, occupant behavior, maintenance/cleaning activities) are deemed to be the most reliable for the prevention of adverse health consequences in children in schools.

  18. Gonadal Development, Spawning and Plasma Sex Steroid Levels of the Indoor Cultured Grunt, Hapalogenys nitens

    PubMed Central

    Kang, Hee Woong; Cho, Jae-Kwon; Son, Maeng-Hyun; Park, Jong Youn; Hong, Chang Gi; Chung, Jae Seung; Chung, Ee-Yung

    2015-01-01

    The gonadosomatic index (GSI), gonadal development and changes in hormones in plasma level of the indoor cultured grunt (Hapalogenys nitens) were investigated by histological study from August 2011 to October 2012. The GSI showed similar trends with gonad developmental stages during the culture periods. Changes in plasma level of estradiol-17β of female H. nitens reached the highest value before the spawning period, and seasonal changes in plasma level of estradiol-17β were similar in trends of oocyte developments and GSI changes. Testosterone levels of male H. nitens reached the highest value before and after the spent stage. Ovarian developmental stages of H. nitens could be classified into early growing stage, late growing stage, mature stage, ripe and spawning stage, recovery and resting stage. The testicular developmental stages could be divided into growing stage, mature stage, ripe and spent stage, and recovery and resting stage. PMID:25949208

  19. Radiation dose due to radon and thoron progeny inhalation in high-level natural radiation areas of Kerala, India.

    PubMed

    Omori, Yasutaka; Tokonami, Shinji; Sahoo, Sarata Kumar; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Hosoda, Masahiro; Kudo, Hiromi; Pornnumpa, Chanis; Nair, Raghu Ram K; Jayalekshmi, Padmavaty Amma; Sebastian, Paul; Akiba, Suminori

    2017-03-20

    In order to evaluate internal exposure to radon and thoron, concentrations for radon, thoron, and thoron progeny were measured for 259 dwellings located in high background radiation areas (HBRAs, outdoor external dose: 3-5 mGy y(-1)) and low background radiation areas (control areas, outdoor external dose: 1 mGy y(-1)) in Karunagappally Taluk, Kerala, India. The measurements were conducted using passive-type radon-thoron detectors and thoron progeny detectors over two six-month measurement periods from June 2010 to June 2011. The results showed no major differences in radon and thoron progeny concentrations between the HBRAs and the control areas. The geometric mean of the annual effective dose due to radon and thoron was calculated as 0.10 and 0.44 mSv, respectively. The doses were small, but not negligible compared with the external dose in the two areas.

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

    PubMed

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

    2017-01-01

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

  1. Indoor Pollutants: Environmental Hazards to Young Children.

    ERIC Educational Resources Information Center

    Noyes, Dorothy

    1987-01-01

    Alerts parents, teachers, and others to some of the leading indoor environmental hazards to young children which are caused by various types of indoor pollutants: cigarette smoke; heating/cooking equipment; asbestos; pesticides; art supplies; radon; and lead. Also suggests ways to reduce these health hazards. (BB)

  2. Indoor air quality levels in a University Hospital in the Eastern Province of Saudi Arabia

    PubMed Central

    El-Sharkawy, Mahmoud F.; Noweir, Mohamed E. H.

    2014-01-01

    Aim of the Study: The complex hospital environment requires special attention to ensure a healthy indoor air quality (IAQ) to protect patients and healthcare workers against hospital-acquired infections and occupational diseases. Poor hospital IAQ may cause outbreaks of building-related illness such as headaches, fatigue, eye, and skin irritations, and other symptoms. The general objective for this study was to assess IAQ inside a large University hospital at Al-Khobar City in the Eastern Province of Saudi Arabia. Materials and Methods: Different locations representing areas where most activities and tasks are performed were selected as sampling points for air pollutants in the selected hospital. In addition, several factors were studied to determine those that were most likely to affect the IAQ levels. The temperature and relative percent humidity of different air pollutants were measured simultaneously at each location. Results: The outdoor levels of all air pollutant levels, except volatile organic compounds (VOCs), were higher than the indoor levels which meant that the IAQ inside healthcare facilities (HCFs) were greatly affected by outdoor sources, particularly traffic. The highest levels of total suspended particulates (TSPs) and those less than 10 microns (PM10) inside the selected hospital were found at locations that are characterized with m4ore human activity. Conclusions: Levels of particulate matter (both PM10 and TSP) were higher than the Air Quality Guidelines (AQGs). The highest concentrations of the fungal species recorded were Cladosporium and Penicillium. Education of occupants of HCF on IAQ is critical. They must be informed about the sources and effects of contaminants and the proper operation of the ventilation system. PMID:24696632

  3. An investigation of infiltration and indoor air quality

    SciTech Connect

    Not Available

    1990-09-01

    A multitask study was performed in the State of New York to provide information for guiding home energy conservation programs while maintaining acceptable indoor air quality. During this study, the statistical distribution of radon concentrations inside 2400 homes was determined. The relationships among radon levels, house characteristics, and sources were also investigated. The direct impact that two specific air infiltration reduction measures -- caulking and weatherstripping of windows and doors, and installation of storm windows and storm doors -- have on house air leakage was investigated in 60 homes. The effect of house age on the impact of weatherization was also evaluated. Indoor and outdoor measurements of NO{sub 2}, CO, SO{sub 2}, and respirable suspended particulates (RSP) were made for 400 homes to determine the effect of combustion sources on indoor air quality and to characterize the statistical distribution of the concentrations. Finally, the combustion source data were combined with the information on air infiltration reduction measures to estimate the potential impact of these measures on indoor air quality. 87 tabs.

  4. Fluid-based radon mitigation technology development for industrial applications

    SciTech Connect

    Liu, K.V.; Gabor, J.D.; Holtz, R.E.; Gross, K.C.

    1996-06-01

    The objective of the radon mitigation technology development effort is to develop an efficient and economical radon gas removal technology based on a fluid absorption process. The technology must be capable of cleaning up a wide range of radon gas stream concentrations to a level that meets EPA gas emission standards for residential and industrial applications. Argonne has recently identified a phenomenon that offers the possibility of radon recovery from the atmosphere with high efficiency at room temperature, and radon release at slightly elevated temperatures (50-60 degrees C.) such a device would offer numerous substantial advantages over conventional cryogenic charcoal systems for the removal of radon. Controlled sources of radon in Argonne`s radon research facility are being used to quantitatively assess the performance of a selected class of absorbing fluids over a range of radon concentrations. This paper will discuss the design of laboratory- and engineering-scale radon absorption units and present some preliminary experimental test results.

  5. Participant evaluation results for two indoor air quality studies

    SciTech Connect

    Hawthorne, A.R.; Dudney, C.S.; Cohen, M.A.; Spengler, J.D.

    1987-01-01

    After two surveys for indoor air pollutants (radon and other chemicals) the homeowners were surveyed for their reactions. The results of these participant evaluation surveys, assuming that the participants that responded to the survey were representative, indicate that homeowners will accept a significant level of monitoring activity as part of an indoor air quality field study. Those participants completing surveys overwhelmingly enjoyed being in the studies and would do it again. We believe that the emphasis placed on positive homeowner interactions and efforts made to inform participants throughout our studies were positive factors in this result. There was no substantial differences noted in the responses between the 70-house study, which included a homeowner compensation payment of $100, and the 300-house study, which did not include a compensation payment. These results provide encouragement to conduct future complex, multipollutant indoor air quality studies when they are scientifically sound and cost effective.

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

    ERIC Educational Resources Information Center

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

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

  7. Contribution of 222Rn in domestic water supplies to 222Rn in indoor air in Colorado homes

    USGS Publications Warehouse

    Lawrence, E.P.; Wanty, R.B.; Nyberg, P.

    1992-01-01

    The contribution of 222Rn from domestic water wells to indoor air was investigated in a study of 28 houses near Conifer, CO. Air concentrations determined by alpha-track detectors (ATDs) and continuous radon monitors were compared with the predictions of a single-cell model. In many of the houses, the water supply was shown to contribute significantly to levels of indoor 222Rn. The data from the ATD study were augmented with a continuous monitoring study of a house near Lyons, CO. The well water in that house has the highest known concentration of 222Rn in water yet reported (93 MBq m-3). The temporal pattern in the indoor 222Rn concentration corresponds to water-use records. In general, it is difficult to quantify the proportion of indoor radon attributable to water use. Several lines of evidence suggest that the single-cell model underestimates this proportion. Continuous- monitoring data, although useful, are impractical due to the cost of the equipment. We propose a protocol for 222Rn measurement based on three simultaneous integrating radon detectors that may help estimate the proportion of indoor 222Rn derived from the water supply.

  8. Radon exhalation from building materials used in Libya

    NASA Astrophysics Data System (ADS)

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

    2014-08-01

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

  9. The radon EDM apparatus

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

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

  10. Indoor pollutant levels from the use of unvented natural gas fireplaces in Boulder, Colorado.

    PubMed

    Dutton, S J; Hannigan, M P; Miller, S L

    2001-12-01

    High CO and NO2 concentrations have been documented in homes with unvented combustion appliances, such as natural gas fireplaces. In addition, polycyclic aromatic hydrocarbons (PAH) are emitted from incomplete natural gas combustion. The acute health risks of CO and NO2 exposure have been well established for the general population and for certain high-risk groups, including infants, the elderly, and people with heart disease or asthma. Health effects from PAH exposure are less well known, but may include increased risk of cancer. We monitored CO emissions during the operation of unvented natural gas fireplaces in two residences in Boulder, CO, at various times between 1997 and 2000. During 1999, we expanded our tests to include measurements of NO2 and PAH. Results show significant pollutant accumulation indoors when the fireplaces were used for extended periods of time. In one case, CO concentrations greater than 100 ppm accumulated in under 2 hr of operation; a person at rest exposed for 10 hr to this environment would get a mild case of CO poisoning with an estimated 10% carboxyhemoglobin level. Appreciable NO2 concentrations were also detected, with a 4-hr time average reaching 0.36 ppm. Similar time-average total PAH concentrations reached 35 ng/m3. The results of this study provide preliminary insights to potential indoor air quality problems in homes operating unvented natural gas fireplaces in Boulder.

  11. Radon exposure of the skin: II. Estimation of the attributable risk for skin cancer incidence.

    PubMed

    Charles, M W

    2007-09-01

    A preceding companion paper has reviewed the various factors which form the chain of assumptions that are necessary to support a suggested link between radon exposure and skin cancer in man. Overall, the balance of evidence was considered to be against a causal link between radon exposure and skin cancer. One factor against causality is evidence, particularly from animal studies, that some exposure of the hair follicles and/or the deeper dermis, as well as the inter-follicular epidermis, is required-beyond the range of naturally occurring alpha particles. On this basis any skin cancer risk due to radon progeny would be due only to beta and gamma components of equivalent dose, which are 10-100 times less than the alpha equivalent dose to the basal layer. Notwithstanding this conclusion against causality, calculations have been carried out of attributable risk (ATR, the proportion of cases occurring in the total population which can be explained by radon exposure) on the conservative basis that the target cells are, as is often assumed, in the basal layer of the epidermis. An excess relative risk figure is used which is based on variance weighting of the data sources. This is 2.5 times lower than the value generally used. A latent period of 20 years and an RBE of 10 are considered more justifiable than the often used values of 10 years and 20 respectively. These assumptions lead to an ATR of approximately 0.7% (0.5-5%) at the nominal UK indoor radon level of 20 Bq m(-3). The range reflects uncertainties in plate-out. Previous higher estimates by various authors have made more pessimistic assumptions. There are some indications that radon progeny plate-out may be elevated out of doors, particularly due to rainfall. Although average UK outdoor radon levels ( approximately 4 Bq m(-3)) are much less than average indoor levels, and outdoor residence time is on average about 10%, this might have the effect of increasing the ATR several-fold. This needs considerable further

  12. 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...

  13. Comparison of background levels of culturable fungal spore concentrations in indoor and outdoor air in southeastern Austria

    NASA Astrophysics Data System (ADS)

    Haas, D.; Habib, J.; Luxner, J.; Galler, H.; Zarfel, G.; Schlacher, R.; Friedl, H.; Reinthaler, F. F.

    2014-12-01

    Background concentrations of airborne fungi are indispensable criteria for an assessment of fungal concentrations indoors and in the ambient air. The goal of this study was to define the natural background values of culturable fungal spore concentrations as reference values for the assessment of moldy buildings. The concentrations of culturable fungi were determined outdoors as well as indoors in 185 dwellings without visible mold, obvious moisture problems or musty odor. Samples were collected using the MAS-100® microbiological air sampler. The study shows a characteristic seasonal influence on the background levels of Cladosporium, Penicillium and Aspergillus. Cladosporium sp. had a strong outdoor presence, whereas Aspergillus sp. and Penicillium sp. were typical indoor fungi. For the region of Styria, the median outdoor concentrations are between 100 and 940 cfu/m³ for culturable xerophilic fungi in the course of the year. Indoors, median background levels are between 180 and 420 cfu/m³ for xerophilic fungi. The I/O ratios of the airborne fungal spore concentrations were between 0.2 and 2.0. For the assessment of indoor and outdoor air samples the dominant genera Cladosporium, Penicillium and Aspergillus should receive special consideration.

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

    PubMed

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

    2017-05-01

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

  15. Radon detection

    DOEpatents

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.

    1994-01-25

    A detector for atmospheric radon using a long range alpha detector as its sensing element is described. An electrostatic filter removes ions from ambient air, while allowing radon atoms to pass into a decay cavity. Here, radon atoms are allowed to decay, creating air ions. These air ions are drawn by a fan through a second electrostatic filter which can be activated or deactivated, and into the long range alpha detector. With the second electrostatic filter activated, no air ions are allowed to pass, and the signal output from the long range alpha detector consists of only the electronic background. With the second electrostatic filter deactivated, air ions and cosmic rays will be detected. The cosmic ray contribution can be minimized by shielding. 3 figures.

  16. Radon detection

    DOEpatents

    MacArthur, Duncan W.; Allander, Krag S.; Bounds, John A.

    1994-01-01

    A detector for atmospheric radon using a long range alpha detector as its sensing element. An electrostatic filter removes ions from ambient air, while allowing radon atoms to pass into a decay cavity. Here, radon atoms are allowed to decay, creating air ions. These air ions are drawn by a fan through a second electrostatic filter which can be activated or deactivated, and into the long range alpha detector. With the second electrostatic filter activated, no air ions are allowed to pass, and the signal output from the long range alpha detector consists of only the electronic background. With the second electrostatic filter deactivated, air ions and cosmic rays will be detected. The cosmic ray contribution can be minimized by shielding.

  17. Long term performance of radon mitigation systems

    SciTech Connect

    Prill, R.; Fisk, W.J.

    2002-03-01

    Researchers installed radon mitigation systems in 12 houses in Spokane, Washington and Coeur d'Alene, Idaho during the heating season 1985--1986 and continued to monitor indoor radon quarterly and annually for ten years. The mitigation systems included active sub-slab ventilation, basement over-pressurization, and crawlspace isolation and ventilation. The occupants reported various operational problems with these early mitigation systems. The long-term radon measurements were essential to track the effectiveness of the mitigation systems over time. All 12 homes were visited during the second year of the study, while a second set 5 homes was visited during the fifth year to determine the cause(s) of increased radon in the homes. During these visits, the mitigation systems were inspected and measurements of system performance were made. Maintenance and modifications were performed to improve system performance in these homes.

  18. Radon in earth-sheltered structures

    USGS Publications Warehouse

    Landa, E.R.

    1984-01-01

    Radon concentration in the indoor air of six residential and three non-residential earth-sheltered buildings in eastern Colorado was monitored quarterly over a nine-month period using passive, integrating detectors. Average radon concentrations during the three-month sampling periods ranged from about 1 to 9 pCi/L, although one building, a poorly ventilated storage bunker, had concentrations as high as 39 pCi/L. These radon concentrations are somewhat greater than those typically reported for conventional buildings (around 1 pCi/L); but they are of the same order of magnitude as radon concentrations reported for energy-efficient buildings which are not earth-sheltered. ?? 1984.

  19. Air levels and mutagenicity of PM-10 in an indoor ice arena

    SciTech Connect

    Georghiou, P.E.; Blagden, P.A. ); Snow, D.A.; Winsor, L. ); Williams, D.T. )

    1989-12-01

    The authors report here their results from a preliminary study to evaluate a methodology for surveying air quality by measuring concentrations of PM-10 and the corresponding concentrations of mutagenic activity. The PM-10 was collected, during several hockey games at an ice arena using an Indoor Air Sampling Impactor (IASI) developed by Marple et al. During the course of the study, smoking restrictions were imposed in the stadium and the impact of these restrictions on PM-10 levels was also evaluated. The mutagenic activities of solvent extracts of the PM-10 were determined using the microsuspension modification of the Samonella typhimurium/microsome test. Mutagenic activity has often been used as a rough index of exposure to potential carcinogens and mutagens and to help define their sources.

  20. Geologic and climatic controls on the radon emanation coefficient

    USGS Publications Warehouse

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

    1997-01-01

    Geologic, pedologic, and climatic factors, including radium content, grain size, siting of radon parents within soil grains or on grain coatings, and soil moisture conditions, determine a soil's emanating power and radon transport characteristics. Data from field studies indicate that soils derived from similar parent rocks in different regions have significantly different emanation coefficients due to the effects of climate on these soil characteristics. An important tool for measuring radon source strength (i.e., radium content) is ground-based and aerial gamma radioactivity measurements. Regional correlations between soil radium content, determined by gamma spectrometry, and soil-gas or indoor radon concentrations can be traced to the influence of climatic and geologic factors on intrinsic permeability and radon emanation coefficients. Data on soil radium content, permeability, and moisture content, when combined with data on emanation coefficients, can form a framework for development of quantitative predictive models for radon generation in rocks and soils.