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Sample records for radon 226

  1. EPA Method 903.1: Radium-226 in Drinking Water Radon Emanation Technique

    EPA Pesticide Factsheets

    SAM lists this method to provide for the analysis of drinking water samples that contain Radium-226, and is based on the emanation and scintillation counting of Radon-222, the immediate decay product of Radium-226.

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

    PubMed

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

    2010-01-01

    Water (226)Ra concentration in springs was measured in regions with high indoor radon: Ural, North Caucasus (Russia), Niska Banja (Serbia), Piestany (Slovakia), and Issyk-Kul (Kyrgyzstan). This paper presents the results for (226)Ra concentration above 0.03 Bq l(-1). Radium in water could indicate indoor radon problem in the region and water investigation is useful at the initial stage of radon survey. Even low (226)Ra concentration in water (0.1-0.6 Bq l(-1)) caused high (226)Ra activity in travertine (up to 1500 Bq kg(-1)), which resulted in indoor radon concentration above 2000 Bq m(-3) (Niska Banja). Copyright 2009 Elsevier Ltd. All rights reserved.

  3. 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. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Radium-226 and radon-222 in the coastal waters of west Florida: high concentrations and atmospheric degassing

    SciTech Connect

    Fanning, K.A.; Breland, J.A. II; Byrne, R.H.

    1982-02-01

    On the central portion of the west Florida continental shelf, radionuclide activities show unusually wide variations: radium-226 activities up to 350 disintegrations per minute per 100 liters, radon-222 activities up to 1300 disintegrations per minute per 100 liters, and deficiencies of radon-222 as low as -- 10 disintegrations per minute per 100 liters. Florida's phosphate-rich strata seem to be the principal source of the radionuclides, with the transfer ocurring directly from sediments or indirectly in streams, ground-water flow, and geothermal springs. Winter storm fronts may enhance radon degassing in the shelf waters.

  5. Measurement of 224Ra and 226Ra activities in natural waters using a radon-in-air monitor

    USGS Publications Warehouse

    Kim, G.; Burnett, W.C.; Dulaiova, H.; Swarzenski, P.W.; Moore, W.S.

    2001-01-01

    We report a simple new technique for measuring low-level radium isotopes (224Ra and 226Ra) in natural waters. The radium present in natural waters is first preconcentrated onto MnO2-coated acrylic fiber (Mn fiber) in a column mode. The radon produced from the adsorbed radium is then circulated through a closed air-loop connected to a commercial radon-in-air monitor. The monitor counts alpha decays of radon daughters (polonium isotopes) which are electrostatically collected onto a silicon semiconductor detector. Count data are collected in energy-specific windows, which eliminate interference and maintain very low backgrounds. Radium-224 is measured immediately after sampling via 220Rn (216Po), and 226Ra is measured via 222Rn (218Po) after a few days of ingrowth of 222Rn. This technique is rapid, simple, and accurate for measurements of low-level 224Ra and 226Ra activities without requiring any wet chemistry. Rapid measurements of short-lived 222Rn and 224Ra, along with long-lived 226Ra, may thus be made in natural waters using a single portable system for environmental monitoring of radioactivity as well as tracing of various geochemical and geophysical processes. The technique could be especially useful for the on-site rapid determination of 224Ra which has recently been found to occur at elevated activities in some groundwater wells.

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

    PubMed

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

    2016-06-01

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

  7. Radon

    EPA Pesticide Factsheets

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

  8. Radon

    MedlinePlus

    ... Risks . Accessed August 19, 2016. U.S. EPA. Indoor Air Quality. What about Radon and Radioactivity in Granite Countertops ? Accessed August 19, 2016 U.S. EPA. Indoor Air Quality. A Citizen's Guide to Radon . Accessed August 19, ...

  9. Radon

    MedlinePlus

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

  10. Radon

    MedlinePlus

    ... comes from the natural breakdown of uranium in soil, rock, and water. Radon is the second leading cause of lung cancer in the United States. There are low levels of radon outdoors. Indoors, there can be high levels. Radon can enter ...

  11. Radon concentration in soil gas and its correlations with pedologies, permeabilities and 226Ra content in the soil of the Metropolitan Region of Belo Horizonte - RMBH, Brazil

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

    The radon concentration in soil gas is directly dependent on the geological characteristics of the area, such as lithology, pedology and on geochemicals, physicals and mineralogicals parameters of the soil. This paper looks for correlations between radon concentrations in soil gas and its soil permeability, 238U, 232Th and 226Ra contents in the soil groups classified by pedologies of Metropolitan Region of Belo Horizonte (RMBH), Minas Gerais, Brazil. The soil gas radon concentrations were determined by using an AlphaGUARD® monitor at about 150 measurement points. In soil samples of the same measurement points, the concentrations of 226Ra were determined by gamma spectrometry (HPGe), and 238U and 232Th by ICP-MS. The soil permeabilities were determined by using the RADON-JOK® permeameter. The mean concentrations of radon in soil gas ranged from 13.6±3.0 kBq m-3 for Litholic Neosols until 60.6±8.7 kBq m-3 for Perferric Red Latosols. The mean of 226Ra activity concentrations presented variation of 12.4±2.5 Bq kg-1 for Litholic Neosols until 50.3±13 Bq kg-1 for Perferric Red Latosols. Approximately 40% of the soils presented high permeability. The areas of different pedologies were classified by Soil Radon Index (SRI), determined by the soil gas radon concentration and permeability. Approximately 53% of the Perferric Red Latosols measurement site could be classified as "High Risk" (Swedish criteria). The preliminary results may indicate an influence of iron formations present very close to the Perferric Red Latosols in the retention of uranium minerals, and hence an increase in the concentration of radon and radium, whereas the series are in equilibrium in the environment.

  12. Uptake of radium-226 from uranium mill tailing by C-3 and C-4 plants and implications for transport of radium-226 and radon-222 into the disposal-site environment

    SciTech Connect

    MacDonell, M.M.

    1986-01-01

    Radium-226 entry into plants grown on uranium mill tailings at pH 6.5 appears to be governed primarily by movement of tailings solution into the plant. The lower transpiration ratios of C-4 photosynthetic plants as compared to C-3 plants result in lower tissue concentrations of radium-225. In each case, the distribution of radium-226 within the plants studied: corn (C-4), dwarf sunflower (C-3), tall fescue grass (C-3), and four species of Panicum (two C-3 and two C-4) exhibited an acropetal gradient, decreasing from the roots where the concentrations are relatively high to the apex of the plant. Tissue concentrations of Ra-226 decreased over time, attributable to increases in biomass while total Ra-226 levels remain constant. Release of radon from vegetated tailings was found to be directly related to the total leaf area of the plant following introduction into the plant of tailings solution. Thus, the plant pathway is shown to be an important mechanism for the transport of radium-226 and radon-222 from mill tailings into the environment. Current tailings disposal site reclamation efforts should consider the effects of the photosynthetic nature of the vegetation species and its total leaf area to reduce the potential for introduction of these elements into the site environment.

  13. Using radon-222 and radium-226 isotopes to deduce the functioning of a coastal aquifer adjacent to a hypersaline lake in NW Iran

    NASA Astrophysics Data System (ADS)

    Amiri, Vahab; Nakhaei, Mohammad; Lak, Razyeh

    2017-10-01

    This study aims to assess the hydrogeochemistry of coastal groundwater, the occurrence of 222Rn and 226Ra, and their isotopic response to salinity and associated chemical compositions of groundwater in the coastal Urmia Aquifer (UA) at the western side of Urmia Lake (UL). The results of the PCA show that 87.3% of groundwater chemistry changes are controlled by six principal components. The interaction between groundwater and coastal igneous and metamorphic rocks in eastern areas (next to the UL) results in complex hydrogeochemical conditions than western areas. Based on correlation of U and salinity, some coastal samples display conservative and the others non-conservative behaviors. Differed from most previous studies, 226Ra and 222Rn concentrations in coastal groundwater samples of UA do not show a good correlation with salinity. Given 10% of groundwater 222Rn is originated from host rocks, the radon concentrations recorded in the coastal groundwater samples are relatively in range that can effectively be supplied by the local rocks (5-49 Bq/l). Results of different chemical and isotopic parameters in this area indicate that there is no direct connection between fresh groundwater and UL saltwater. This is because that the hard and thick salty layer in the lakebed acts as an impermeable barrier to prevent the underground hydraulic connection. Results show that removing the salty layer of UL as an option to progress in rehabilitation program of this lake may result in more hydraulic connection between the lake and groundwater resources in some areas.

  14. A Calibration and Quality Assurance Program for Environmental Radon Measurements

    PubMed Central

    Fisenne, Isabel M.; George, Andreas C.; Keller, Helen W.

    1990-01-01

    The ideal facility for assessing the quality of radon measurements at environmental levels consists of: (1) an instrument whose response to radon and its progeny is determined from measurements of a certified or standard 226Ra source, and (2) a calibration room with a known radon concentration. The linkage between these two elements and additional quality control requirements are discussed here for some Environmental Measurements Laboratory radon measurements programs. PMID:28179764

  15. 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

  16. Calibration of scintillation cells for radon-222 measurements

    NASA Astrophysics Data System (ADS)

    Aakko, Kyllikki; Oksanen, Eero

    The calibration, of a radon-222 measurement system is described. The detector of the system is based on ZnS(Ag) coated scintillation cell. Evacuated cells are used for grab sample measurements of radon-222 in air. Three types of radioactive sources were used to evaluate the calibration coefficient. Standard activities were generated from commercially available solid and liquid radium-226 sources, and from a self-made radon-222 source whose activity was crosschecked by gamma spectrometric measurements. Radium-226 sources are traceable to US National Institute of Standards and Technology reference standards. Sources of error on calibration are discussed. Best accuracy was obtained by gamma spectrometrically crosschecked radon source. Considerable difficulties were encountered with the traditional method of emanating a known activity of radon-222 from a standard liquid radium-226 source. Three separate solid radium-226 sources gave results with rather large deviations. The final error weighted coefficients agree well with international intercalibration results.

  17. 40 CFR 61.226 - Reconsideration of rescission and reinstatement of this subpart.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Emission Standards for Radon Emissions From the Disposal of Uranium Mill Tailings § 61.226 Reconsideration... by EPA and NRC or the tailings closure plan (radon) (i.e., contained in the license) requirements establishing milestones for the purpose of emplacing a permanent radon barrier that will achieve compliance...

  18. 40 CFR 61.226 - Reconsideration of rescission and reinstatement of this subpart.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Emission Standards for Radon Emissions From the Disposal of Uranium Mill Tailings § 61.226 Reconsideration... by EPA and NRC or the tailings closure plan (radon) (i.e., contained in the license) requirements establishing milestones for the purpose of emplacing a permanent radon barrier that will achieve compliance...

  19. 40 CFR 61.226 - Reconsideration of rescission and reinstatement of this subpart.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Emission Standards for Radon Emissions From the Disposal of Uranium Mill Tailings § 61.226 Reconsideration... by EPA and NRC or the tailings closure plan (radon) (i.e., contained in the license) requirements establishing milestones for the purpose of emplacing a permanent radon barrier that will achieve compliance...

  20. 40 CFR 61.226 - Reconsideration of rescission and reinstatement of this subpart.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Emission Standards for Radon Emissions From the Disposal of Uranium Mill Tailings § 61.226 Reconsideration... by EPA and NRC or the tailings closure plan (radon) (i.e., contained in the license) requirements establishing milestones for the purpose of emplacing a permanent radon barrier that will achieve compliance...

  1. 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.

  2. 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

  3. 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.

  4. 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)

  5. 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)

  6. Comparison study and thoron interference test of different radon monitors.

    PubMed

    Sumesh, C G; Kumar, A Vinod; Tripathi, R M; Puranik, V D

    2013-03-01

    A comparison study and thoron interference test for different continuous radon monitors were carried out. The comparison study includes three passive diffusion monitors [one pulse ionisation chamber based-Alpha Guard and two silicon semi-conductor based-Radon Scout Plus (RSP)] and one silicon semi-conductor-based active radon thoron discriminating monitor--RAD 7. Radon emanation standard, supplied by National Institute of Science and Technology, has been utilised for the comparison study to qualify the calibration of the continuous radon monitors. All the instruments showed good agreement with the estimated radon concentration using (226)Ra/(222)Rn emanation standard. It was found that the active radon monitoring system is having a higher initial response towards the transient radon concentration than the passive radon monitors studied. The instruments measuring radon concentration without energy discrimination are likely to have some sensitivity towards the thoron concentration. Thus, thoron interference study was carried out in the above monitors. Nine percent interference in measured radon concentration in the Alpha Guard monitor and 4 % interference in the semi-conductor-based RSP monitors was observed. Study indicates that the interference of thoron in radon monitors depends on the area of diffusion of gas, volume of detection and sensitivity factor.

  7. 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

  8. Radon in soil gas in Kosovo.

    PubMed

    Kikaj, Dafina; Jeran, Zvonka; Bahtijari, Meleq; Stegnar, Peter

    2016-11-01

    An assessment of the radiological situation due to exposure to radon and gamma emitting radionuclides was conducted in southern Kosovo. This study deals with sources of radon in soil gas. A long-term study of radon concentrations in the soil gas was carried out using the SSNTDs (CR-39) at 21 different locations in the Sharr-Korabi zone. The detectors were exposed for an extended period of time, including at least three seasonal periods in a year and the sampling locations were chosen with respect to lithology. In order to determine the concentration of the natural radioactive elements (238)U and (226)Ra, as a precursor of (222)Rn, soil samples were collected from each measuring point from a depth of 0.8 m, and measured by gamma spectrometry. The levels (Bq kg(-1)) of naturally occurring radionuclides and levels (kBq m(-3)) of radon in soil gas obtained at a depth 0.8 m of soil were: 21-53 for (226)Ra, 22-160 for (238)U and 0.295-32 for (222)Rn. With respect to lithology, the highest value for (238)U and (226)Ra were found in limestone and the highest value for (222)Rn was found in metamorphic rocks. In addition, the results showed seasonal variations of the measured soil gas radon concentrations with maximum concentration in the spring months.

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

    SciTech Connect

    Lewis, B.A.G.

    1985-01-01

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

  10. 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.

  11. Granulation effects on the radon emanation rate.

    PubMed

    Bikit, I; Mrda, D; Grujic, S; Kozmidis-Luburic, U

    2011-05-01

    The radon emanation and the granulation effect on the emanation rate of several building materials (ceramic plates, sand, red brick and siporex brick) with different (226)Ra concentrations were investigated. A ball mill was used to achieve different granulations of the materials. The particle size distributions were determined by a particle size analyser (Mastersizer 2000). The increase in the (222)Rn concentration inside a closed chamber (volume ≈5.4 × 10(-3) m(3)) due to emanation from each material with different granulations was measured by an alpha spectrometer (RAD7). Thus, time-dependent curves for radon concentrations were obtained. The highest radon emanation coefficient (27 %) was obtained for the siporex sample with the smallest grain size (0.34 µm). For the ceramic pads, the granulation effect was negligible and the emanation coefficient was very low (∼0.4 %). The strongest influence of granulation on the radon emanation rate was found for the siporex brick sample.

  12. 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.

  13. 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.

  14. 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.

  15. Radon 222

    Integrated Risk Information System (IRIS)

    Radon 222 ; CASRN 14859 - 67 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  16. 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.

  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. Radon Testing in Schools.

    ERIC Educational Resources Information Center

    Wheeler, Robert

    1989-01-01

    Schools may be a significant source of radon exposure for children and staff. Describes radon detection kits and technologies, when to use them, and what action to take given the results of a radon test. (MLF)

  19. 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)

  20. Radon Testing in Schools.

    ERIC Educational Resources Information Center

    Wheeler, Robert

    1989-01-01

    Schools may be a significant source of radon exposure for children and staff. Describes radon detection kits and technologies, when to use them, and what action to take given the results of a radon test. (MLF)

  1. Correlation of radon and thoron concentrations with natural radioactivity of soil in Zonguldak, Turkey

    NASA Astrophysics Data System (ADS)

    Koray, Abdullah; Akkaya, Gizem; Kahraman, Ayşegül

    2017-02-01

    Radon and thoron gases are produced by the decay of the radioactive elements those are radium and thorium in the soil. In this study, the correlations between soil radon and thoron concentration with their parent nuclide (226Ra and 232Th) concentrations in collected soil samples from the same locations were evaluated. The result of the measurement shows that the distribution of radon and thoron in soil showed the same tendency as 226Ra and 232Th distribution. It was found a weak correlation between the radon and the 226Ra concentration (R =0.57), and between the thoron and the 232Th concentration (R=0.64). No strong correlation was observed between soil-gas radon and thoron concentration (R = 0.29).

  2. 40 CFR 61.207 - Radium-226 sampling and measurement procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Radium-226 sampling and measurement... for Radon Emissions From Phosphogypsum Stacks § 61.207 Radium-226 sampling and measurement procedures... § 61.206, the owner or operator of a phosphogypsum stack shall measure the average...

  3. 40 CFR 61.207 - Radium-226 sampling and measurement procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Radium-226 sampling and measurement... for Radon Emissions From Phosphogypsum Stacks § 61.207 Radium-226 sampling and measurement procedures... § 61.206, the owner or operator of a phosphogypsum stack shall measure the average...

  4. 40 CFR 61.207 - Radium-226 sampling and measurement procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Radium-226 sampling and measurement... for Radon Emissions From Phosphogypsum Stacks § 61.207 Radium-226 sampling and measurement procedures... § 61.206, the owner or operator of a phosphogypsum stack shall measure the average...

  5. Radon in the soil air of Estonia.

    PubMed

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

    2017-01-01

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

  6. Radon emanation from radium specific adsorbents.

    PubMed

    Alabdula'aly, Abdulrahman I; Maghrawy, Hamed B

    2010-01-01

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

  7. Development of radon sources with a high stability and a wide range

    SciTech Connect

    Fukutsu, K.; Yamada, Y.

    2013-12-15

    A solid {sup 222}Rn (radon) source using a fibrous and porous SiC ceramic disk was developed. The emission rate of radon emanated from the disk depended on the content of {sup 226}Ra and the sintering temperature. A {sup 226}Ra sulfate ({sup 226}RaSO{sub 4}) solution was dropped on a fibrous SiC ceramic disk (33 mmφ) of 1 mm in thickness, and sintered at 400 °C. The radon concentration from a disk containing {sup 226}Ra of 1.85 MBq was measured to be 38 kBq m{sup −3} at a carrier airflow rate of 0.5 L min{sup −1}. By adjusting the {sup 226}Ra content or the sweep airflow rate, the radon concentrations were easily controlled over a wide range of over three orders of magnitude. The concentration was very stable for a long term. The compactness of the source disk made is easy for handling the source container and the shielding of gamma radiation from {sup 226}Ra and its decay products. Such advantages in a radon generation system are desirable for experiments of high-level, large-scale radon exposure.

  8. Development of radon sources with a high stability and a wide range

    NASA Astrophysics Data System (ADS)

    Fukutsu, K.; Yamada, Y.

    2013-12-01

    A solid 222Rn (radon) source using a fibrous and porous SiC ceramic disk was developed. The emission rate of radon emanated from the disk depended on the content of 226Ra and the sintering temperature. A 226Ra sulfate (226RaSO4) solution was dropped on a fibrous SiC ceramic disk (33 mmϕ) of 1 mm in thickness, and sintered at 400 °C. The radon concentration from a disk containing 226Ra of 1.85 MBq was measured to be 38 kBq m-3 at a carrier airflow rate of 0.5 L min-1. By adjusting the 226Ra content or the sweep airflow rate, the radon concentrations were easily controlled over a wide range of over three orders of magnitude. The concentration was very stable for a long term. The compactness of the source disk made is easy for handling the source container and the shielding of gamma radiation from 226Ra and its decay products. Such advantages in a radon generation system are desirable for experiments of high-level, large-scale radon exposure.

  9. Development of radon sources with a high stability and a wide range.

    PubMed

    Fukutsu, K; Yamada, Y

    2013-12-01

    A solid (222)Rn (radon) source using a fibrous and porous SiC ceramic disk was developed. The emission rate of radon emanated from the disk depended on the content of (226)Ra and the sintering temperature. A (226)Ra sulfate ((226)RaSO4) solution was dropped on a fibrous SiC ceramic disk (33 mmφ) of 1 mm in thickness, and sintered at 400 °C. The radon concentration from a disk containing (226)Ra of 1.85 MBq was measured to be 38 kBq m(-3) at a carrier airflow rate of 0.5 L min(-1). By adjusting the (226)Ra content or the sweep airflow rate, the radon concentrations were easily controlled over a wide range of over three orders of magnitude. The concentration was very stable for a long term. The compactness of the source disk made is easy for handling the source container and the shielding of gamma radiation from (226)Ra and its decay products. Such advantages in a radon generation system are desirable for experiments of high-level, large-scale radon exposure.

  10. One cubic metre NIST traceable radon test chamber.

    PubMed

    Kotrappa, P; Stieff, F

    2008-01-01

    With the availability of the National Institute of Standards and Technology (NIST) Radon Emanation Standard with a content of approximately 5000 Bq of 226Ra, it is possible to build a flow through a practical radon test chamber. A standard glove box with four gloves and a transfer port is used. Air is pumped through a flow integrator, water jar for humidification and NIST source holder, and into the glove box through a manifold. A derived theoretical expression provides the calculated radon concentration inside the chamber. The calculation includes a derived decay correction due to the large volume and low flow rate of the system. Several calibrated continuous radon monitors and passive integrating electret ion chambers tested in the chamber agreed fairly well with the calculated radon concentrations. The chamber is suitable for handling the calibration of several detectors at the same time.

  11. Effective radium-226 concentration in meteorites

    NASA Astrophysics Data System (ADS)

    Girault, Frédéric; Perrier, Frédéric; Moreira, Manuel; Zanda, Brigitte; Rochette, Pierre; Teitler, Yoram

    2017-07-01

    The analysis of noble gases in meteorites provides constraints on the early solar system and the pre-solar nebula. This requires a better characterization and understanding of the capture, production, and release of noble gases in meteorites. The knowledge of transfer properties of noble gases for each individual meteorite could benefit from using radon-222, radioactive daughter of radium-226. The radon-222 emanating power is commonly quantified by the effective radium-226 concentration (ECRa), the product of the bulk radium-226 concentration and of the emanation coefficient E, which represents the probability of one decaying radium-226 to inject one radon-222 into the free porous network. Owing to a non-destructive, high-sensitivity accumulation method based on long photomultiplier counting sessions, we are now able to measure ECRa of meteorite samples, which usually have mass smaller than 15 g and ECRa < 0.5 Bq kg-1. We report here the results obtained from 41 different meteorites, based on 129 measurements on 70 samples using two variants of our method, showing satisfactory repeatability and a detection limit below 10-2 Bq kg-1 for a sample mass of 1 g. While two meteorites remain below detection level, we obtain for 39 meteorites heterogeneous ECRa values with mean (min-max range) of ca. 0.1 (0.018-1.30) Bq kg-1. Carbonaceous chondrites exhibit the largest ECRa values and eucrites the smallest. Such values are smaller than typical values from most terrestrial rocks, but comparable with those from Archean rocks (mean of ca. 0.18 Bq kg-1), an end-member of terrestrial rocks. Using uranium concentration from the literature, E is inferred from ECRa for all the meteorite samples. Values of E for meteorites (mean 40 ± 4%) are higher than E values for Archean rocks and reported values for lunar and Martian soils. Exceptionally large E values likely suggest that the 238U-226Ra pair would not be at equilibrium in most meteorites and that uranium and/or radium are most

  12. Transport of radon in still water

    NASA Astrophysics Data System (ADS)

    Syahrir

    2005-11-01

    A new method was developed to measure the effectiveness of water in reducing the release of radon emanating from 226Ra-bearing sand into air. Fick's law on diffusion was used to model the transport of radon in water including the impact associated with radioactive decay. A multi-region, one-dimensional, steady-state transport model was used to analyze the movement of radon through a sequential column of air, water and air. An effective diffusion coefficient was determined by varying the thickness of the water column to predict the transport of 222Rn through particular thickness of water. A one-region, one-dimensional transient diffusion equation was developed to investigate the build up of radon at the end of the water column until a steady-state, equilibrium condition was achieved. This build up with time is characteristic of the transport rate of radon in water and established the basis for estimating the effective diffusion coefficient for 222 Rn in water. The results suggest that convective forces other than molecular diffusion impact the transport of 222Rn through the water barrier. An effective diffusion coefficient is defined that includes effects of molecular diffusion and convection to describe the transport of radon in water. Several experimental arrangements were evaluated to examine the influence of physical parameters on the radon transport. The effective diffusion coefficients measured in these experiments are 6.8 x 10 -4 +/- 28% and 3.5 x 10-4 +/- 34% cm2 sec-1 for the steady-state and transient diffusion approaches, respectively. Water barriers ranging in thickness from 30--50 cm reduce the amount of radon released from the radium-bearing source material by a factor of 0.3--0.1, respectively.

  13. Exposure to atmospheric radon.

    PubMed Central

    Steck, D J; Field, R W; Lynch, C F

    1999-01-01

    We measured radon (222Rn) concentrations in Iowa and Minnesota and found that unusually high annual average radon concentrations occur outdoors in portions of central North America. In some areas, outdoor concentrations exceed the national average indoor radon concentration. The general spatial patterns of outdoor radon and indoor radon are similar to the spatial distribution of radon progeny in the soil. Outdoor radon exposure in this region can be a substantial fraction of an individual's total radon exposure and is highly variable across the population. Estimated lifetime effective dose equivalents for the women participants in a radon-related lung cancer study varied by a factor of two at the median dose, 8 mSv, and ranged up to 60 mSv (6 rem). Failure to include these doses can reduce the statistical power of epidemiologic studies that examine the lung cancer risk associated with residential radon exposure. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9924007

  14. Exposure to atmospheric radon.

    PubMed

    Steck, D J; Field, R W; Lynch, C F

    1999-02-01

    We measured radon (222Rn) concentrations in Iowa and Minnesota and found that unusually high annual average radon concentrations occur outdoors in portions of central North America. In some areas, outdoor concentrations exceed the national average indoor radon concentration. The general spatial patterns of outdoor radon and indoor radon are similar to the spatial distribution of radon progeny in the soil. Outdoor radon exposure in this region can be a substantial fraction of an individual's total radon exposure and is highly variable across the population. Estimated lifetime effective dose equivalents for the women participants in a radon-related lung cancer study varied by a factor of two at the median dose, 8 mSv, and ranged up to 60 mSv (6 rem). Failure to include these doses can reduce the statistical power of epidemiologic studies that examine the lung cancer risk associated with residential radon exposure.

  15. Consumer's Guide to Radon Reduction

    MedlinePlus

    ... provide feedback, or report a problem. Radon Indoor Air Quality Home Page Radon Home Local Radon Zones and State Contact Information Individuals and Families Radon Publications Home Buyers and ... Air Bed Bugs Chemicals and Toxics Climate Change Environmental ...

  16. 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

  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. 12 CFR 226.37-226.38 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false 226.37-226.38 Section 226.37-226.38 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Special Rules for Certain Home Mortgage Transactions §§ 226.37-226.38 ...

  19. 12 CFR 226.40-226.45 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false 226.40-226.45 Section 226.40-226.45 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Special Rules for Certain Home Mortgage Transactions §§ 226.40-226.45 ...

  20. 48 CFR 452.226-70-452.226-72 - [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false 452.226-70-452.226-72 Section 452.226-70-452.226-72 Federal Acquisition Regulations System DEPARTMENT OF AGRICULTURE CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 452.226-70—452.226-72...

  1. Radon emanation from backfilled mill tailings in underground uranium mine.

    PubMed

    Sahu, Patitapaban; Mishra, Devi Prasad; Panigrahi, Durga Charan; Jha, Vivekananda; Patnaik, R Lokeswara; Sethy, Narendra Kumar

    2014-04-01

    Coarser mill tailings used as backfill to stabilize the stoped out areas in underground uranium mines is a potential source of radon contamination. This paper presents the quantitative assessment of radon emanation from the backfilled tailings in Jaduguda mine, India using a cylindrical accumulator. Some of the important parameters such as (226)Ra activity concentration, bulk density, bulk porosity, moisture content and radon emanation factor of the tailings affecting radon emanation were determined in the laboratory. The study revealed that the radon emanation rate of the tailings varied in the range of 0.12-7.03 Bq m(-2) s(-1) with geometric mean of 1.01 Bq m(-2) s(-1) and geometric standard deviation of 3.39. An increase in radon emanation rate was noticed up to a moisture saturation of 0.09 in the tailings, after which the emanation rate gradually started declining with saturation due to low diffusion coefficient of radon in the saturated tailings. Radon emanation factor of the tailings varied in the range of 0.08-0.23 with the mean value of 0.21. The emanation factor of the tailings with moisture saturation level over 0.09 was found to be about three times higher than that of the absolutely dry tailings. The empirical relationship obtained between (222)Rn emanation rate and (226)Ra activity concentration of the tailings indicated a significant positive linear correlation (r = 0.95, p < 0.001). This relationship may be useful for quick prediction of radon emanation rate from the backfill material of similar nature.

  2. Radon release and dispersion from an open pit uranium mine

    SciTech Connect

    Kisieleski, W.E.

    1980-06-01

    Radon-222 flux from representative sections of the United Nuclear St. Anthony open-pit mine complex was measured. The collected radon was adsorbed on activated charcoal and the radon activity was measured by gamma spectroscopy. System design, calibration, and the procedure to determine radon flux density (pCi/m/sup 2/.s) are described. A continuous series of radon flux densities were measured over a 5-month period at a control point in the mine. The average flux density at the control point was 1.9 pCi/m/sup 2/.s. A close correlation between radon flux density variations and changes in barometric pressure was observed by a comparison of meteorological data and average daily radon flux density measured at the control point. The release rate from each section of the mine was calculated from the average radon flux density and the area of the section, as determined from enlarged aerial photographs. The average radon flux density for eight locations over the ore-bearing section was 7.3 pCi/m/sup 2/.s. The average flux density for four locations over undisturbed topsoil was 0.17 pCi/m/sup 2/.s. The average Ra-226 content of ten samples taken from the ore-bearing region was 102 pCi/g ore. The ratio of radon flux density to radium content (specific flux) was 0.072. The release rate from the entire St. Anthony open pit was determined to be 3.5 x 10/sup 5/ pCi/s. This rate is comparable to the natural release of radon from one square mile of undisturbed topsoil. 16 refs., 31 figs., 11 tabs.

  3. What Is Radon?

    MedlinePlus

    ... materials may contribute significantly to radon exposure. Some granite countertops may expose people to different levels of ... experts agree that while a small portion of granite countertops might give off increased levels of radon, ...

  4. Radon in Schools

    MedlinePlus

    ... cannot ignore this problem." Kathryn Whitfill, National PTA President. The EPA ranks indoor radon among the most ... our children demands no less. Keith Geiger, NEA President. Top of Page Radon gas decays into radioactive ...

  5. Radon: A health problem

    SciTech Connect

    Pucci, J.; Gaston, S.

    1990-01-01

    Nurses can and should function as effective teachers about the potential hazards to health of radon contamination in the home as well as become activists in the development of health care policy on radon.

  6. Radon and Cancer

    MedlinePlus

    ... Cancer Kidney (Renal Cell) Cancer Leukemia Liver Cancer Lung Cancer Lymphoma Pancreatic Cancer Prostate Cancer Skin Cancer Thyroid ... does radon cause cancer? How many people develop lung cancer because of exposure to radon? How did scientists ...

  7. Radon-222 as a Natural Tracer for Monitoring the Remediation of NAPL Contamination in the Subsurface

    DTIC Science & Technology

    2006-11-06

    PID Photoionization Detector PITT Partitioning Interwell Tracer Test QA/QC Quality Assurance/Quality Control Ra Radium - 226 Rn Radon-222 STOMP...Rn is produced in the subsurface by the continuous decay of naturally occurring radium - 226 . In the absence of NAPL contamination, the aqueous Rn...is produced in the subsurface by the continuous decay of naturally occurring Ra- 226 (Ra). In the absence of NAPL contamination, the aqueous Rn

  8. 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.

  9. Radon Guide for Tenants

    EPA Pesticide Factsheets

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

  10. Radon: Detection and treatment

    SciTech Connect

    Loken, S.; Loken, T. )

    1989-11-01

    Within the last few years, natural radon exposure in non-industrial settings, primarily homes, has become a health concern. Research has demonstrated that many homes throughout the United States have radon concentrations much higher than the legal federal limits set for miners. Thousands of unsuspecting people are being exposed to high levels of radiation. It is estimated that up to 15 percent of lung cancers are caused from radon. This is a significant health risk. With basic knowledge of the current information on radon, a primary health care provider can address patients' radon concerns and make appropriate referrals.

  11. 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.

  12. 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.

  13. Radon is out

    SciTech Connect

    Harley, J.H.

    1992-12-31

    This paper discusses some facets of outdoor radon. There is only one source of radon - the decay of radium. Radium is everywhere but the bulk is in soil, rock, and ocean sediments. Soil porosity is a prime factor in radon movement. Exhalation from soil is fed by the high concentrations of radon in soil gas. Because the surface soil is losing radon to the atmosphere, soil gas concentration would be expected to increase with depth. There is a wide range of air radon concentrations, with marked seasonal and diurnal variations. Atmospheric stability is certainly a major factor - radon increases during inversions and decreases when the inversion breaks up. In addition, temperature, soil moisture, snow cover, and wind direction all play a part. Different investigators sometimes come to contrary conclusions on the effects of these factors. They are probably all correct - for the conditions in effect at the time - since no simple generalities exist for most factors.

  14. 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.

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

    PubMed

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

    2017-02-01

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

  16. The mathematical model of radon-222 accumulation in underground mines

    NASA Astrophysics Data System (ADS)

    Klimshin, A.

    2012-04-01

    Necessity to control underground mine air radon level arises during building and operating mines as well as auto and railway tunnels including those for metros. Calculation of underground mine air radon level can be fulfilled for estimation of potential radon danger of area for underground structure building. In this work the new mathematical model of radon accumulation in underground mines has been suggested. It takes into consideration underground mine dimensions, air exchange factor and soils ability to emanate radon. The following assumptions have been taken for model development. It is assumed that underground mine is a cylinder of length L and of base area S. Due to ventilation atmosphere air of volume activity Catm, is coming in through one cylinder base and is going out of volume activity Cind from underground mine. Diffusion radon flux is coming in through side surfaces of underground mine. The sources of this flux are radium-226 atoms distributed evenly in rock. For simplification of the task it considered possible to disregard radon emanation by loosened rock and underground waters. As a result of solution of the radon diffusion equation the following expression for calculation of radon volume activity in underground space air has been got: 2·r0 ·λv ·Catm-·l·K0(r0/l)-+D-·K1(r0/l)·C0- Cind = 2·(λ+ λv)·r0 ·l·K0 (r0/l)+ D ·K1(r0/l) . The following designations are used in this expression: Kν(r) - the second genus modified Bessel's function, C0 - equilibrium radon volume activity in soil air, l - diffusion radon length in soil, D - radon diffusion factor, r0 - radius of underground tunnel, λv - factor of air exchange. Expression found may be used for calculation of the minimum factor of necessary air exchange for ensuring safe radon levels in underground spaces. With this worked out model expected levels of radon volume activity were calculated for air in the second metro line underground spaces in the city of Yekaterinburg, Russia.

  17. Radon concentrations in a spa in Serbia.

    PubMed

    Manic, G; Petrovic, S; Vesna, Manic; Popovic, Dragana; Todorovic, Dragana

    2006-05-01

    The paper presents the results of indoor radon concentration survey in 201 homes and offices in Niska Banja (the Spa of Nis), a well-known health resort and a spa in the South-East of Serbia. Radon indoor concentrations were determined by active charcoal method, according to standard EPA procedure. The indoor radon concentrations were in the range of up to 200 Bq/m(3) (47%), from 200-600 Bq/m(3) (26%) and over 600 Bq/m(3) (27%). Three areas of extremely high average radon concentrations were found (1,340-4,340 Bq/m(3)), with a maximum above 13,000 Bq/m(3). The content of natural radionuclides ((226)Ra, (214)Pb, (214)Bi, (235)U, (228)Ac, (212)Pb, (212)Bi, (208)Tl, (40)K) and (137)Cs, as well as the content of total uranium, thorium and potassium in mud used in peloidotherapy in the Health Institute "Niska Banja" was determined, too. The activities of the radionuclides were determined on an HPGe detector, by standard gamma spectroscopy. The results indicated considerably high amounts of total uranium and thorium (0.021 g/kg mud and 0.003 g/kg mud, respectively), due to the karsts origin of the soil.

  18. Atmosphere purification of radon and radon daughter elements

    DOEpatents

    Stein, L.

    1974-01-01

    A method of removing radon and radon daughter elements from an atmosphere containing these elements by passing the atmosphere through a bed of fluorinating compound whereby the radon and radon daughters are oxidized to their respective fluorides is discussed. These fluorides adhere to the fluorinating compound and are thus removed from the atmosphere which may then be recirculated. A method for recovering radon and separating radon from its daughter elements is also described. (Official Gazette)

  19. 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.

  20. Calculation of radon diffusion coefficient and diffusion length for different building construction materials

    NASA Astrophysics Data System (ADS)

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

    2009-08-01

    The diffusion of radon in dwellings is a process determined by the radon concentration gradient across the building material structure between the radon source and the surrounding air, and can be a significant contributor to indoor radon inflow. Radon can originate from the deeply buried deposit beneath homes and can migrate to the surface of earth. Radon emanates to the surfaces mainly by diffusion processes from the point of origin following α-decay of 226Ra in underground soil and building materials used, in the construction of floors, walls, and ceilings. In the present study radon diffusion through some building materials viz. coarse sand and stone dust of different grain size has been carried out using LR-115 type II solid-state nuclear track detectors (SSNTDs). The radon diffusion coefficients and diffusion lengths through these building construction materials have been calculated. The effect of grain size on radon diffusion through these building materials shows the decrease in radon diffusion with decrease in grain size.

  1. [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.

  2. 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)

  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. 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.

  5. Radon assay and purification techniques

    SciTech Connect

    Simgen, Hardy

    2013-08-08

    Radon is a source of background in many astroparticle physics experiments searching for rare low energy events. In this paper an overview about radon in the field is given including radon detection techniques, radon sources and material screening with respect to radon emanation. Finally, also the problem of long-lived radioactive {sup 222}Rn-daughters and the question of gas purification from radon is addressed.

  6. Radon emanation from low-grade uranium ore.

    PubMed

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

    2013-12-01

    Estimation of radon emanation in uranium mines is given top priority to minimize the risk of inhalation exposure due to short-lived radon progeny. This paper describes the radon emanation studies conducted in the laboratory as well as inside an operating underground uranium mine at Jaduguda, India. Some of the important parameters, such as grade/(226)Ra activity, moisture content, bulk density, porosity and emanation fraction of ore, governing the migration of radon through the ore were determined. Emanation from the ore samples in terms of emanation rate and emanation fraction was measured in the laboratory under airtight condition in glass jar. The in situ radon emanation rate inside the mine was measured from drill holes made in the ore body. The in situ(222)Rn emanation rate from the mine walls varied in the range of 0.22-51.84 × 10(-3) Bq m(-2) s(-1) with the geometric mean of 8.68 × 10(-3) Bq m(-2) s(-1). A significant positive linear correlation (r = 0.99, p < 0.001) between in situ(222)Rn emanation rate and the ore grade was observed. The emanation fraction of the ore samples, which varied in the range of 0.004-0.089 with mean value of 0.025 ± 0.02, showed poor correlation with ore grade and porosity. Empirical relationships between radon emanation rate and the ore grade/(226)Ra were also established for quick prediction of radon emanation rate from the ore body.

  7. 40 CFR 61.207 - Radium-226 sampling and measurement procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... for Radon Emissions From Phosphogypsum Stacks § 61.207 Radium-226 sampling and measurement procedures. (a) Before removing phosphogypsum from a stack for distribution in commerce pursuant to § 61.204, or § 61.206, the owner or operator of a phosphogypsum stack shall measure the average...

  8. 40 CFR 61.207 - Radium-226 sampling and measurement procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... for Radon Emissions From Phosphogypsum Stacks § 61.207 Radium-226 sampling and measurement procedures. (a) Before removing phosphogypsum from a stack for distribution in commerce pursuant to § 61.204, or § 61.206, the owner or operator of a phosphogypsum stack shall measure the average...

  9. 40 CFR 61.226 - Reconsideration of rescission and reinstatement of this subpart.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Emission Standards for Radon Emissions From the Disposal of Uranium Mill Tailings § 61.226 Reconsideration... owners and operators of non-operational uranium mill tailings disposal sites that are licensed by the NRC... enforce, in significant part, the regulations governing the disposal of uranium mill tailings promulgated...

  10. Public perceptions of radon risk

    SciTech Connect

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

    1993-03-01

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

  11. Activity measurements of radon from construction materials.

    PubMed

    Fior, L; Nicolosi Corrêa, J; Paschuk, S A; Denyak, V V; Schelin, H R; Soreanu Pecequilo, B R; Kappke, J

    2012-07-01

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60×60×60 cm3 were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of 226Ra, 232Th and 40K. The values for the index of the activity concentration (I), radium equivalent activity (Raeq), and external hazard index (Hext) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year). Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Atmosphere purification of radon and radon daughter elements

    DOEpatents

    Stein, L.

    1973-12-11

    A method for purifying an atmosphere of radon and radon daughter elements which may be contained therein by contacting the atmosphere with a fluorinating solution, whereby the radon and radon daughters are oxidized to their respective fluorides is discussed. The fluorides dissolve in the fluorinating solutlon and are removed from the atmosphere, which may then be recirculated. (Official Gazette)

  13. 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 ...

  14. 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 ...

  15. 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

  16. LARGE BUILDING RADON MANUAL

    EPA Science Inventory

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

  17. 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)

  18. 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)

  19. LARGE BUILDING RADON MANUAL

    EPA Science Inventory

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

  20. Radon measurements for earthquake prediction in northern India

    SciTech Connect

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

    1992-01-01

    Earthquake prediction is based on the observation of precursory phenomena, and radon has emerged as a useful precursor in recent years. In India, where 55% of the land area is in active seismic zones, considerable destruction was caused by the earthquakes of Kutch (1819), Shillong (1897), Kangra (1905), Bihar-Nepal (1934), Assam (1956), Koyna (1967), Bihar-Nepal (1988), and Uttarkashi (1991). Radon ([sup 222]Rn) is produced by the decay of radium ([sup 226]Ra) in the uranium decay series and is present in trace amounts almost everywhere on the earth, being distributed in soil, groundwater, and lower levels of atmosphere. The purpose of this study is to find the value in radon monitoring for earthquake prediction.

  1. 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%.

  2. Mutagenicity of radon and radon daughters

    SciTech Connect

    Evans, H.H.

    1991-01-01

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

  3. Mutagenicity of radon and radon daughters

    NASA Astrophysics Data System (ADS)

    Evans, H. H.

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

  4. Radium 226,228

    Integrated Risk Information System (IRIS)

    Integrated Risk Information System ( IRIS ) Chemical Assessment Summary U.S . Environmental Protection Agency National Center for Environmental Assessment Radium 226,228 ; CASRN 7440 - 14 - 4 , Human health assessment information on a chemical substance is included in the IRIS database only after a

  5. Radon Resources for Home Buyers and Sellers

    MedlinePlus

    ... provide feedback, or report a problem. Radon Indoor Air Quality Home Page Radon Home Local Radon Zones and State Contact Information Individuals and Families Radon Publications Home Buyers and ... Air Bed Bugs Chemicals and Toxics Climate Change Environmental ...

  6. Radon emanation during compression, fracturing and heating of granites

    NASA Astrophysics Data System (ADS)

    Pili, E.; Nicolas, A.; Girault, F.; Schubnel, A.; Fortin, J.; Passelègue, F. X.; Richon, P.

    2013-12-01

    Radon emanation during compression, fracturing and heating of granites É. Pili1,2, A. Nicolas3, F. Girault3, A. Schubnel3, J. Fortin3, F. Passelègue3, P. Richon1 1CEA, DAM, DIF, F-91297 Arpajon, France 2Institut de Physique du Globe, Sorbonne Paris Cité, 1 rue Jussieu, F-75005 Paris, France 3Ecole Normale Supérieure, 24 rue Lhomond, F-75005 Paris, France Precursory radon emissions have been reported previously in various seismically active areas. Nevertheless such observations, only partially understood, are the subject of much skepticism. Radon-222 is a radioactive gas, daughter of radium-226 from alpha-decay in the uranium-238 decay chain that is naturally present in rocks and soils. Its escape is facilitated by preferential pathways such as fractures. Its half-life is 3.8 days only. As a consequence, radon may accumulate during short period only, and is thought to be released prior, during and after earthquakes as stress is discharged and new fluid pathways are made available. However, the physical processes involved in radon emanation during stress variations remain mostly unknown in the field and poorly studied in the laboratory. Here, we investigate radon emanation from various granite samples: Isla Craig, Westerly, La Peyratte and various leucogranites. Radon emanation and diffusion length, measured first on intact samples, are compared with measurements performed after heating at 850°C. Despite extensive thermal fracturing, radon emanation decreases irreversibly after heating compared to intact sample, and the higher the heating temperature the smaller the radon emanation. This is explained by the disappearance of water-film at grain boundaries, which plays an important role in radon percolation through the porous space, and then, at higher temperatures, by dehydration and melting of biotites where radium is concentrated. The recoil range of radon is likely shorter in melted biotites than in intact ones. The effect of mechanical fracturing on radon

  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. Radon Optical Processing in Radon Space.

    DTIC Science & Technology

    1986-06-15

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

  9. Models for the analysis of radon-exposed populations.

    PubMed

    Lubin, J H

    1988-01-01

    Radon-222 is a radioactive decay product of radium-226 and uranium-238, which are found throughout the crust of the earth. Studies of underground miners clearly show that exposure to radon and its decay products increases the risk of developing lung cancer. Data on standardized mortality ratios from eight cohort studies indicate that the radon-lung cancer relationship is statistically homogeneous, even though cohorts are from different types of mines and from different countries. Regression methods for cohort data based on a Poisson probability model permit a thorough consideration of risk patterns. In this report, we review these methods, wherein the disease rate in each cell of a multi-way table is modeled as a function of the cross-classifying variables. The National Academy of Sciences' Committee on the Biological Effects of Ionizing Radiation uses the Poisson regression approach to develop a model for age-specific lung cancer risk which depends on cumulative exposure, age at risk, and time since exposure. This model is reviewed and its implications discussed. The most important determinant of lung cancer is cigarette smoking. This paper discusses relative risk models for analysis of joint exposure to radon and tobacco products. The review of available studies suggests that the joint relationship of radon and smoking with lung cancer is consistent with a multiplicative model, but a submultiplicative relationship is most likely. An additive model is rejected.

  10. Models for the analysis of radon-exposed populations.

    PubMed Central

    Lubin, J. H.

    1988-01-01

    Radon-222 is a radioactive decay product of radium-226 and uranium-238, which are found throughout the crust of the earth. Studies of underground miners clearly show that exposure to radon and its decay products increases the risk of developing lung cancer. Data on standardized mortality ratios from eight cohort studies indicate that the radon-lung cancer relationship is statistically homogeneous, even though cohorts are from different types of mines and from different countries. Regression methods for cohort data based on a Poisson probability model permit a thorough consideration of risk patterns. In this report, we review these methods, wherein the disease rate in each cell of a multi-way table is modeled as a function of the cross-classifying variables. The National Academy of Sciences' Committee on the Biological Effects of Ionizing Radiation uses the Poisson regression approach to develop a model for age-specific lung cancer risk which depends on cumulative exposure, age at risk, and time since exposure. This model is reviewed and its implications discussed. The most important determinant of lung cancer is cigarette smoking. This paper discusses relative risk models for analysis of joint exposure to radon and tobacco products. The review of available studies suggests that the joint relationship of radon and smoking with lung cancer is consistent with a multiplicative model, but a submultiplicative relationship is most likely. An additive model is rejected. PMID:3051700

  11. 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.

  12. Recommendations for Radon Research

    EPA Pesticide Factsheets

    This report, undertaken upon the initiative of the Radiation Advisory Committee, is the first Science Advisory Board report to look at the entire field of radon research and the contribution additional scientific understanding can make on EPA's policies.

  13. Health Risk of Radon

    MedlinePlus

    ... related lung cancer in women. Top of Page Biological Effects of Ionizing Radiation (BEIR) VI Report: "The ... of Sciences' (NAS) latest report on radon, the Biological Effects of Ionizing Radiation (BEIR) VI Report (1999). ...

  14. Protocols for Radon and Radon Decay Product Measurements in Homes

    EPA Pesticide Factsheets

    This May 1993 document, is a guidance document.The objective of this document is to provide information, recommendations and technological guidance for anyone providing measurement services using 15 radon and radon decay product measurement methods.

  15. Comparison of active and passive methods for radon exhalation from a high-exposure building material.

    PubMed

    Abbasi, A; Mirekhtiary, F

    2013-12-01

    The radon exhalation rates and radon concentrations in granite stones used in Iran were measured by means of a high-resolution high purity Germanium gamma-spectroscopy system (passive method) and an AlphaGUARD model PQ 2000 (active method). For standard rooms (4.0 × 5.0 m area × 2.8 height) where ground and walls have been covered by granite stones, the radon concentration and the radon exhalation rate by two methods were calculated. The activity concentrations of (226)Ra in the selected granite samples ranged from 3.8 to 94.2 Bq kg(-1). The radon exhalation rate from the calculation of the (226)Ra activity concentration was obtained. The radon exhalation rates were 1.31-7.86 Bq m(-2)h(-1). The direction measurements using an AlphaGUARD were from 218 to 1306 Bq m(-3) with a mean of 625 Bq m(-3). Also, the exhalation rates measured by the passive and active methods were compared and the results of this study were the same, with the active method being 22 % higher than the passive method.

  16. Radon tightness of different sample sealing methods for gamma spectrometric measurements of ²²⁶Ra.

    PubMed

    Mauring, Alexander; Gäfvert, Torbjörn

    2013-11-01

    Different methods for sealing sample containers for (222)Rn when measuring (226)Ra through its progenies (214)Pb and (214)Bi using gamma-ray spectrometry have been investigated. Results show that a method consisting of vacuum packaging of the sample container in a sealed aluminium lined bag gives excellent results for ensuring radon tightness. However, care should be taken to fill the sample container completely in order to avoid systematic errors due to radon accumulating in the void volume.

  17. A study of radon and thoron release from Egyptian building materials using polymeric nuclear track detectors.

    PubMed

    Hafez, A F; Hussein, A S; Rasheed, N M

    2001-02-01

    The free exhalation rates of both thoron and radon, the specific activities of 224Ra, and 226Ra, and the physical properties, such as the emanation coefficients and radon effective diffusion coefficient of several building material samples were determined using LR-115 and CR-39 polymeric nuclear track detectors. The free areal exhalation rate was measured by the sealed cup-technique, whereas the radium content was obtained by the alpha-autoradiographic method. The calibration coefficient for thoron measurements in air using cylindrical cup equipped with LR-115 detector was estimated. Moreover, the calibration coefficients for measurements of the specific activities of 224Ra and 226Ra were also evaluated. New method was developed for evaluating the emanation coefficient as well as the diffusion coefficient of radon isotopes in the studied materials.

  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. 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.

  20. Geological factors controlling radon hazardous concentration in groundwater

    NASA Astrophysics Data System (ADS)

    Przylibski, T. A.

    2009-04-01

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

  1. Radium on soil mineral surfaces: Its mobility under environmental conditions and its role in radon emanation. Final report

    SciTech Connect

    Turekian, K.K.

    1997-08-01

    The ultimate source of {sup 222}Rn to the atmosphere is, of course, {sup 226}Ra. Tracking the mobility of radium therefore is part of the story of radon flux assessment. The study of radium mobility and radon flux measurements has involved virtually all the reservoirs at the Earth`s surface. These include soils, groundwaters, coastal waters and the atmosphere. The attempt to understand the mobility of radium involved the study of almost all the radium isotopes ({sup 226}Ra, {sup 228}Ra, {sup 224}Ra) and the parent and daughters of these isotopes.

  2. A correlation between soil descriptions and {sup 226}Ra concentrations in Florida soils

    SciTech Connect

    Harrison, D.P.

    1992-12-31

    The soil radium content in Florida is highly variable. The range in radium concentrations, where the samples involved in this study are concerned, is from 0.1 pCi/g to 18.5 pCi/g. Low {sup 226}Ra concentrations (0.1 to 5 pCi/g) are evidenced in sands, moderate concentrations (5 to 11 pCi/g) are found in silt and gravel, and high {sup 226}Ra concentrations (>11 pCi/g) are found in soil horizons with shell, clay, and strata with phosphate. Strata containing phosphate yields a high concentration of {sup 226}Ra. The information obtained in this study, soil descriptions with their corresponding {sup 226}Ra concentrations, comes from geological cores drilled by geotechnical consultants with gamma spectrometry analysis performed by high resolution gamma spectroscopy. Concentration; of {sup 226}Ra generally increase with depth. These cores are usually terminated at 20 feet deep, with some cores being shallower than this due to hitting bedrock or encountering the water table. These frequency distributions give the core-logging geologist an approximate concentration of {sup 226}Ra based on the description of the soil. Since the correlation of {sup 226}Ra and soil descriptions can be used as a tool in assigning indoor radon potential, this study is of importance to land managers, contractors, developers, and regulating agencies who are attempting to place standards on tracts of land with {sup 226}Ra concentration used as a criterion.

  3. 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.

  4. Mechanisms and sources of radon entry in buildings constructed with modern technologies.

    PubMed

    Zhukovsky, M V; Vasilyev, A V

    2014-07-01

    To investigate the influence of modern building construction technologies on the accumulation of radon indoor, 20 rooms in buildings constructed using mostly monolithic concrete or aerated concrete blocks have been studied. Dominance of the diffusion mechanism of radon entry in buildings constructed with modern technologies has been established. As a result of computer simulations it was found that the main contribution to the variability of radon concentration was made by changes in the ventilation rate. At a low ventilation rate (<0.2 h(-1)) radon concentration above 200 Bq m(-3) can be observed for residential buildings. There is a need for the regulation of the radium-specific activity in building materials. According to the estimates of this study, the content of 226Ra in building materials should not exceed the value of 100 Bq kg(-1).

  5. 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.

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

    PubMed

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

    2016-02-01

    Radon ((222)Rn) levels in air and water have been analyzed continuously for almost a year in Las Caldas de Besaya thermal spa, north Spain. Radon is a naturally occurring noble gas from the decay of radium ((226)Ra) both constituents of radioactive uranium 238 series. It has been recognized as a lung carcinogen by the World Health Organization (WHO) and International Agency for Research on Cancer (IARC). Furthermore the Royal Decree R.D 1439/2010 of November, 2010 establishes the obligation to study occupational activities where workers and, where appropriate, members of the public are exposed to inhalation of radon in workplaces such as spas. Together with radon measures several physico-chemical parameters were obtained such as pH, redox potential, electrical conductivity and air and water temperature. The devices used for the study of the temporal evolution of radon concentration have been the RTM 2100, the Radon Scout and gamma spectrometry was complementarily used to determine the transfer factor of the silicone tubes in the experimental device. Radon concentrations obtained in water and air of the spa are high, with an average of 660 Bq/l and 2900 Bq/m(3) respectively, where water is the main source of radon in the air. Radiation dose for workers and public was estimated from these levels of radon. The data showed that the thermal processes can control the behavior of radon which can be also influenced by various physical and chemical parameters such as pH and redox potential. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Evaluation of Exposure to Radon Levels in Relation to Climatic Conditions at a Superfund Site.

    NASA Astrophysics Data System (ADS)

    Merrill, Elaine Alice

    1995-11-01

    Workers at a Superfund site have expressed concern that they may be exposed to elevated levels of radon gas, especially when meteorology is suitable. The site, formally a uranium processing site, stores the world's largest quantity of Ra-226 in two concrete silos. A layer of bentonite foam was placed over the contents of the silos in 1991 as a means to reduce the amount of radon emissions. Hourly real-time outdoor and indoor site radon data covering an entire year was statistically evaluated in relation to meteorological data covering the same time period. The hourly data was found to be lognormally distributed. Radon levels were highest during the early morning hours and during the summer months. Both outdoor and indoor concentrations were found to significantly vary with temporal and climatic factors, namely wind direction and relative humidity. Radon levels in the work areas were not found to be statistically different from off-site levels. Only radon levels in the vicinity of the storage silos, which is an exclusion zone, were significantly higher than levels off-site. Hence, the protective bentonite covering seems to be effective in reducing radon emissions. Two methods were used to calculate a hypothetical dose, based upon the annual average concentrations of radon in the work areas onsite, the BEIR IV method and the NCRP method, respectively. The BEIR IV method, which accounts for the activity ratio of radon and its daughter products, resulted in a slightly higher dose than the NCRP method. As expected, based on the mean concentrations, the hypothetical annual exposures from radon in the work areas of the site were below recommended exposure limits.

  8. Radon: Counseling patients about risk

    SciTech Connect

    Birrer, R.B. )

    1990-09-01

    Exposure to radon and its decay products has increased as the United States has changed from an outdoor society to a largely indoor society. Radon, which is found primarily in the soil, enters houses and buildings through cracks, holes and pipes in foundation walls and floors. Although radon is suspected of being a significant cause of lung cancer, comparisons with other risk factors cannot yet be made. Radon levels in the home can be measured with commercially available kits. Guidelines for reducing the amount of radon in a home are provided by the U.S. Environmental Protection Agency.18 references.

  9. 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.

  10. 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.

  11. Relation between "terra rossa" from the Apulia aquifer of Italy and the radon content of groundwater: Experimental results and their applicability to radon occurrence in the aquifer

    NASA Astrophysics Data System (ADS)

    Tadolini, T.; Spizzico, M.

    The radon-222 (222Rn) activity in groundwater of the Apulian karstic aquifer in southern Italy is as great as 500 Becquerel per liter (Bq/L) locally. Normal radium-226 (226Ra) activity in the limestone and calcareous dolomites of the aquifer is not enough to explain such a high level. Laboratory investigations identified high 226Ra activity in the "terra rossa," the residuum occupying fissures and cavities in the bedrock, and also the relation between (1) 226Ra-bearing bedrock and "terra rossa" and (2) 222Rn in water. The "terra rossa" is the primary source of the radon in the groundwater. The experimental results show the need to characterize the "terra rossa" of Apulia on the basis of 226Ra activity and also to study the distribution and variations in 222Rn activity over time in the aquifer. Résumé L'activité du radon-222 (222Rn) dans les eaux souterraines de l'aquifère karstique des Pouilles, dans le sud de l'Italie, atteint localement 500 Becquerel par litre (Bq/L). L'activité normale du radium-226 (226Ra) dans les calcaires et dans les calcaires dolomitiques de l'aquifère n'est pas assez élevée pour expliquer des valeurs aussi élevées. Des analyses de laboratoire ont mis en évidence une forte activité en 226Ra dans la terra rossa, remplissage de fissures et de cavités de la roche, ainsi qu'une relation entre (1) la roche et la terra rossa contenant du 226Ra et (2) le 222Rn dans l'eau. La terra rossa est la source primaire de radon dans l'eau souterraine. Les résultats expérimentaux montrent qu'il est nécessaire de caractériser la terra rossa des Pouilles par son activité en 226Ra et d'étudier la distribution et les variations de l'activité en 222Rn au cours du temps dans l'aquifère. Resumen La actividad del radon-222 (222Rn) en el agua subterránea del acuífero cárstico de Apulia, al sur de Italia, alcanza localmente los 500Bq/L. La actividad normal del radio-226 (226Ra) en las calcitas y dolomitas del acuífero no es suficiente para

  12. Radon programmes and health marketing.

    PubMed

    Fojtikova, Ivana; Rovenska, Katerina

    2011-05-01

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

  13. What Teachers Should Know about Radon.

    ERIC Educational Resources Information Center

    Bettis, Clifford; Throckmorton, Carl

    1991-01-01

    Attempts to clear up misunderstandings about radon and outlines information teachers can convey to their students. Includes a brief history of radon, health threats posed by radon, methods to measure radon quantities, homeowner risks and preventative actions, and a glossary of radon terms. (MDH)

  14. What Teachers Should Know about Radon.

    ERIC Educational Resources Information Center

    Bettis, Clifford; Throckmorton, Carl

    1991-01-01

    Attempts to clear up misunderstandings about radon and outlines information teachers can convey to their students. Includes a brief history of radon, health threats posed by radon, methods to measure radon quantities, homeowner risks and preventative actions, and a glossary of radon terms. (MDH)

  15. Radon assay for SNO+

    SciTech Connect

    Rumleskie, Janet

    2015-12-31

    The SNO+ experiment will study neutrinos while located 6,800 feet below the surface of the earth at SNOLAB. Though shielded from surface backgrounds, emanation of radon radioisotopes from the surrounding rock leads to back-grounds. The characteristic decay of radon and its daughters allows for an alpha detection technique to count the amount of Rn-222 atoms collected. Traps can collect Rn-222 from various positions and materials, including an assay skid that will collect Rn-222 from the organic liquid scintillator used to detect interactions within SNO+.

  16. Radon assay for SNO+

    NASA Astrophysics Data System (ADS)

    Rumleskie, Janet

    2015-12-01

    The SNO+ experiment will study neutrinos while located 6,800 feet below the surface of the earth at SNOLAB. Though shielded from surface backgrounds, emanation of radon radioisotopes from the surrounding rock leads to back-grounds. The characteristic decay of radon and its daughters allows for an alpha detection technique to count the amount of Rn-222 atoms collected. Traps can collect Rn-222 from various positions and materials, including an assay skid that will collect Rn-222 from the organic liquid scintillator used to detect interactions within SNO+.

  17. Radon fluxes measured with the MANOP bottom lander

    NASA Astrophysics Data System (ADS)

    Berelson, W. M.; Buchholtz, M. R.; Hammond, D. E.; Santschi, P. H.

    1987-07-01

    At five Pacific Ocean sites, radon fluxes were determined from water samples collected by the MANOP Lander, from measurements of 222Rn and 226Ra concentrations in Lander-collected box core sediments, and from measurements of excess radon in the water column. At MANOP sites H and M, fluxes (all in atoms m -2 s -1) determined with Lander water samples (2200 and 1540 ± 480) agree within the measurement uncertainty with water column standing crop measurements (2220 ± 450, 2040 ± 470). At MANOP site C, the diffusive flux calculated from measurements of 226Ra in box core sediments (550 ± 20), the integrated deficiency of 222Rn in the sediments (720 ± 90), and the water column standing crop (500 ± 160) are in agreement, but all are about twice as large as the single Lander water measurement of the radon flux (330). At MANOP site S radon fluxes from measurements of Lander water (3000 ± 260) are in agreement with the predicted diffusive flux from site S sediments (2880), and both fluxes are close to the lower end of the range of water column standing crop measurements (3000-5170). In San Clemente Basin, California, the Lander water flux measurements at four different sites vary by a factor of 3 due to variability in the sediment radium distribution, but the average (1030 ± 190) is close to the water column standing crop value (780 ± 230). Because there is excellent agreement between the fluxes measured with Lander water samples and the predicted diffusive fluxes in most cases, diffusion must be the primary process controlling benthic exchange of radon at the sites studied. The agreement between the Lander water flux estimates and the water column standing crop estimates indicates that the MANOP Lander functions as an accurate benthic flux chamber in water depths ranging from 1900 to 4900 m. In San Clemente Basin, surficial sediments are enriched in manganese and radium, due to manganese cycling near the sediment-water interface. Molecular diffusion of radon from

  18. Caves, mines and subterranean spaces: hazard and risk from exposure to radon.

    NASA Astrophysics Data System (ADS)

    Crockett, R. G. M.; Gillmore, G. K.

    2009-04-01

    Radon is a naturally occurring radioactive gas. It is colourless, odourless and chemically inert. The most hazardous isotope is 222Rn. Radon is formed in the natural environment by the radioactive decay of the element uranium (238U) and is a daughter product of daughter product of radium (226Ra). Uranium and radium are found, in differing degrees, in a wide range of rocks, soils (and building materials that are made from these). Radon concentrations in caves, e.g. limestone caves such as the Great Cave of Niah, Borneo, and caves in the Mendips and Peak District in the UK, has been documented and reveal that both (prehistoric) cave-dwellers and other users such as archaeologists are at risk from exposure to radon a naturally occurring radioactive gas. In general, but dependent on cave geometry and ventilation, radon concentration increases with increasing distance from the entrance, implying that the hazard also increases with distance from the entrance. With regard to mines and mining operations, as well as modern extraction of uranium and radium ores, both ores commonly occur alongside other metallic ores, e.g. silver at Schneeberg and Joachimsthal, and tin in Cornwall, and in some instances, waste from earlier metalliferious mining activity has itself been ‘mined' for uranium and/or radium ores. It is not solely the miners and other subterranean workers which are at risk, other workers and local inhabitants are also at risk. Also, that risk is not eliminated by protection against dust/airborne particulates: the risk from inhalation of radon is only reduced by reducing the inhalation of radon, i.e. use of breathing apparatus. Amongst the general population, radon is the second most significant cause of lung cancer behind tobacco smoking. Estimates vary but 6-9% of lung-cancers are attributable to radon and approximately 2% all cancer deaths are attributable to radon. These proportions will increase in higher-radon environments such as caves, mines and mining

  19. 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

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

    PubMed

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

    2017-01-01

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

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

    PubMed

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

    2015-06-01

    (222)Rn is a naturally occurring gas created from the decay of (226)Ra. The long-term health risk of breathing radon is lung cancer. One particular place where indoor radon concentrations can exceed national guidelines is in wastewater treatment plants (WWTPs) where treatment processes may contribute to ambient airborne concentrations. The aim of this paper was to study the radon concentration decrease after the application of corrective measures in a Spanish WWTP. According to first measures, air radon concentration exceeded International Commission Radiologica1 Protection (ICRP) normative (recommends intervention between 400 and 1000 Bq m(-3)). Therefore, the WWTP improved mechanical forced ventilation to lower occupational exposure. This measure allowed to increase the administrative controls, since the limitation of workers access to the plant changed from 2 h d(-1) (considering a maximum permissible dose of 20 mSv y(-1) averaged over 5 y) to 7 h d(-1). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. The Chemistry of Radon

    NASA Astrophysics Data System (ADS)

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

    1982-01-01

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

  3. Publications about Radon

    EPA Pesticide Factsheets

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

  4. 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.

  5. Environmental radon studies in Mexico.

    PubMed

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

    2007-04-01

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

  6. 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...

  7. 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...

  8. 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.

  9. Radium-226 and barium as tracers of water masses in the North Atlantic (GA01-GEOTRACES)

    NASA Astrophysics Data System (ADS)

    Le Roy, Emilie; Sanial, Virginie; Charette, Matthew; Henderson, Paul; Jacquet, Stéphanie; García-Ibáñez, Maribel; Pérez, Fiz; Lherminer, Pascale; Souhaut, Marc; Jeandel, Catherine; Lacan, François; van Beek, Pieter

    2017-04-01

    In this study, we report concentrations of radium-226 (226Ra, t1/2=1602 y) and barium determined along the GEOVIDE section conducted in the North Atlantic (May-July 2014; Portugal-Greenland-Canda) in the framework of the international GEOTRACES program. A high vertical resolution (up to 22 depths per station) was achieved by analyzing small volumes (˜10 L) of seawater for 226Ra using a radon emanation technique. We will present the distribution of 226Ra activities and barium concentrations in contrasting biogeochemical regions of the North Atlantic (Iberian margin, West European Basin, Reykjanes Ridge, Irminger Sea, Greenland margin and Labrador Sea). These regions strongly differ in terms of boundary inputs, biogeochemistry and deep water formation. We observe a linear correlation between 226Ra and barium along the GEOVIDE section, which results from the dominantly conservative behavior of the two tracers. However, deviations from the linear correlation between 226Ra and Ba are found in several places. The potential causes for such deviations are investigated. Optimum multi-parameter (OMP) analysis was thus used to distinguish the relative importance of physical transport (i.e., water mass mixing) from non-conservative processes (sedimentary, river or hydrothermal inputs; uptake by particles) on the 226Ra and Ba distribution in the North Atlantic.

  10. 22 CFR 226.10 - Purpose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Purpose. 226.10 Section 226.10 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Pre-award Requirements § 226.10 Purpose. Sections 226.11 through 226.17 prescribe forms...

  11. 22 CFR 226.10 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Purpose. 226.10 Section 226.10 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Pre-award Requirements § 226.10 Purpose. Sections 226.11 through 226.17 prescribe forms and...

  12. 22 CFR 226.70 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Purpose. 226.70 Section 226.70 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS After-the-Award Requirements § 226.70 Purpose. Sections 226.71 through 226.73 contain closeout...

  13. Residential construction code impacts on radon

    SciTech Connect

    Galbraith, S.; Brennan, T.; Osborne, M.C.

    1988-04-01

    The paper discusses residential construction-code impacts on radon. It references existing residential construction codes that pertain to the elements of construction that impact either the ability to seal radon out of houses or the ability to achieve good soil ventilation for radon control. Several inconsistencies in the codes that will impact radon resistant construction are identified. Resolution of these resulting radon issues is necessary before specification-style building codes can be developed to achieve radon-resistant construction.

  14. 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.

  15. Compact anti-radon facility

    SciTech Connect

    Fajt, L.; Kouba, P.; Mamedov, F.; Smolek, K.; Štekl, I.

    2015-08-17

    Suppression of radon background is one of main tasks in ultra-low background experiments. The most promising technique for suppression of radon is its adsorption on charcoal. Within the frame of the NEMO-3 experiment, radon trapping facility (RTF) was installed in Modane underground laboratory in 2004. Based on long-term experience with this facility a new compact transportable anti-radon facility was constructed in cooperation among IEAP CTU, SÚRO and ATEKO company. The device provides 20m{sup 3}/h of purified air (air radon activity at the output ∼10mBq/m{sup 3}). The basic features and preliminary results of anti-radon device testing are presented.

  16. An integrated radon flux monitor

    NASA Astrophysics Data System (ADS)

    Abdelrazek, M. M.

    1984-07-01

    A radon flux monitor suitable for measuring radon flux emanating from cracks or small surface areas is described. The monitor consists of a charcoal canister, an air pump and a steel container. Radon gas exhaled from a crack or from a surface is collected inside a steel container (10 cm × 10 cm × 10 cm) and is simultaneously circulated through a charcoal canister using an air pump. Radon flux is estimated by measuring the gamma ray activity of the radon gas absorbed by the charcoal. Experimental investigations showed that an air flow of 8 1/min was found adequate for the purpose of the present work. A calibration coefficient representing the ratio of radon flux measured by the monitor to the actual flux was found to be 0.81∓0.03. Experimental results showed that this monitor gives fairly accurate and reliable results.

  17. 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.

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

    USGS Publications Warehouse

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

    2004-01-01

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

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

    PubMed

    Wood, Warren W; Kraemer, Thomas F; Shapiro, Allen

    2004-01-01

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

  20. The health risk of radon

    SciTech Connect

    Conrath, S.M.; Kolb, L.

    1995-10-01

    Although radon is the second leading cause of lung cancer in the United States, second only to cigarette smoking, many members of the public are not aware that radon is one of the most serious environmental cancer risks in the US. Based on extensive data from epidemiological studies of underground miners, radon has been classified as a known human carcinogen. In contrast to most pollutants, the assessment of human risk from radon is based on human occupational exposure data rather than animal data. That radon causes lung cancer has been well established by the scientific community. More is known about radon than most other cancer causing environmental carcinogens. While there are some uncertainties involved when estimating radon risk to the public, it is important to recognize that the risk information is based on human data and that the uncertainties have been addressed in the risk assessment. The US Environmental Protection Agency (EPA) estimates that the number of annual US lung cancer deaths due to residential radon exposures is approximately 14,000 with an uncertainty range of 7,000 to 30,000. The abundant information on radon health risks that supports EPA`s risk assessment indicates that recommendations for public action by the federal government and other public health organizations constitute prudent public policy.

  1. Radon exhalation rate and natural radionuclide content in building materials of high background areas of Ramsar, Iran.

    PubMed

    Bavarnegin, E; Fathabadi, N; Vahabi Moghaddam, M; Vasheghani Farahani, M; Moradi, M; Babakhni, A

    2013-03-01

    Radon exhalation rates from building materials used in high background radiation areas (HBRA) of Ramsar were measured using an active radon gas analyzer with an emanation container. Radon exhalation rates from these samples varied from below the lower detection limit up to 384 Bq.m(-2) h(-1). The (226)Ra, (232)Th and (40)K contents were also measured using a high resolution HPGe gamma- ray spectrometer system. The activity concentration of (226)Ra, (232)Th and (40)K content varied from below the minimum detection limit up to 86,400 Bq kg(-1), 187 Bq kg(-1) and 1350 Bq kg(-1), respectively. The linear correlation coefficient between radon exhalation rate and radium concentration was 0.90. The result of this survey shows that radon exhalation rate and radium content in some local stones used as basements are extremely high and these samples are main sources of indoor radon emanation as well as external gamma radiation from uranium series. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Radon and aerosol release from open-pit uranium mining

    SciTech Connect

    Thomas, V.W.; Nielson, K.K.; Mauch, M.L.

    1982-08-01

    The quantity of /sup 222/Rn (hereafter called radon) released per unit of uranium produced from open pit mining has been determined. A secondary objective was to determine the nature and quantity of airborne particles resulting from mine operations. To accomplish these objectives, a comprehensive study of the release rates of radon and aerosol material to the atmosphere was made over a one-year period from April 1979 to May 1980 at the Morton Ranch Mine which was operated by United Nuclear Corporation (UNC) in partnership with Tennessee Valley Authority (TVA). The mine is now operated for TVA by Silver King Mines. Morton Ranch Mine was one of five open pit uranium mines studied in central Wyoming. Corroborative measurements were made of radon flux and /sup 226/Ra (hereafter called radium) concentrations of various surfaces at three of the other mines in October 1980 and again at these three mines plus a fourth in April of 1981. Three of these mines are located in the Powder River Basin, about 80 kilometers east by northeast of Casper. One is located in the Shirley Basin, about 60 km south of Casper, and the remaining one is located in the Gas Hills, approximately 100 km west of Casper. The one-year intensive study included simultaneous measurement of several parameters: continuous measurement of atmospheric radon concentration near the ground at three locations, monthly 24-hour radon flux measurements from various surfaces, radium analyses of soil samples collected under each of the flux monitoring devices, monthly integrations of aerosols on dichotomous aerosol samplers, analysis of aerosol samplers for total dust loading, aerosol elemental and radiochemical composition, aerosol elemental composition by particle size, wind speed, wind direction, temperature, barometric pressure, and rainfall.

  3. Radon Reduction Experience at a Former Uranium Processing Facility

    SciTech Connect

    Eger, K. J.; Rutherford, L.; Rickett, K.; Fellman, R.; Hungate, S.

    2004-02-29

    Approximately 6,200 cubic meters of waste containing about 2.0E8 MBq of radium-226 are stored in two large silos at the Fernald Site in southwest Ohio. The material is scheduled for retrieval, packaging, off site shipment and disposal by burial. Air in the silos above the stored material contained radon-222 at a concentration of 7.4 E5 Bq/L. Short-lived daughters formed by decay in these headspaces generated dose rates at contact with the top of the silos up to 1.05 mSv/hr and there complicate the process of retrieval. A Radon Control System (RCS) employing carbon adsorption beds has been designed under contract with the Fluor Fernald to remove most of the radon in the headspaces and maintain lower concentrations during periods when work on or above the domes is needed. Removing the radon also removes the short-lived daughters and reduces the dose rate near the domes to 20 to 30 {mu}Sv/hr. Failing to remove the radon would be costly, in the exposure of personnel needed to work extended periods at these moderate dose rates, or in dollars for the application of remote retrieval techniques. In addition, the RCS minimizes the potential for environmental releases. This paper describes the RCS, its mode of operation, and early experiences. The results of the test described herein and the experience gained from operation of the RCS during its first phase of continuous operation, will be used to determine the best air flow, and air flow distribution, the most desirable number and sequence number and sequence of adsorption beds to be used and the optimum application of air recycle within the RCS.

  4. 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.

  5. Radon Treatment Controversy

    PubMed Central

    Zdrojewicz, Zygmunt; Strzelczyk, Jadwiga (Jodi)

    2006-01-01

    In spite of long traditions, treatments utilizing radon-rich air or water have not been unequivocally embraced by modern medicine. The objective of this work is to examine factors that contribute to this continuing controversy. While the exact mechanism of radon's effect on human body is not completely understood, recent advances in radiobiology offer new insights into biochemical processes occurring at low-level exposures to ionizing radiation. Medical evidence and patients' testimonials regarding effectiveness of radon spa treatments of various ailments, most notably rheumatoid arthritis are accumulating worldwide. They challenge the premise of the Linear-No-Threshold (LNT) theory that the dose-effect response is the same per unit dose regardless of the total dose. Historically, such inference overshadowed scientific inquiries into the low-dose region and lead to a popular belief that no amount of radiation can be good. Fortunately, the LNT theory, which lacks any scientific basis, did not remain unchallenged. As the reviewed literature suggests, a paradigm shift, reflected in the consideration of hormetic effects at low-doses, is gaining momentum in the scientific community worldwide. The impetus comes from significant evidence of adaptive and stimulatory effects of low-levels of radiation on human immune system. PMID:18648641

  6. 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.

  7. Radiation Protection. Measurement of radioactivity in the environment - Air- radon 222. A proposed ISO standard.

    NASA Astrophysics Data System (ADS)

    Gillmore, G.; Woods, M.

    2009-04-01

    Radon isotopes (222, 220, 219) are radioactive gases produced by the disintegration of radium isotopes 226, 224 and 223, which are decay products of uranium238, thorium232 and uranium235 respectively. All are found in the earth's crust. Solid elements, also radioactive, are produced by radon disintegration. Radon is classed as a rare gas in the periodic table of elements, along with helium, argon, neon, krypton and xenon. When disintegrating, radon emits alpha particles and generates solid decay products, which are also radioactive (polonium, bismuth, lead etc.). The potential danger of radon lies in its solid decay products rather than the gas itself. Whether or not they are attached aerosols, radon decay products can be inhaled and deposited in the bronchopulmonary tree to varying depths according to their size. Radon today is considered to be the main source of human exposure to natural radiation. At the international level, radon accounts for 52% of global average exposure to natural radiation. Isotope 222 (48%) is far more significant than isotope 220 (4%), whilst isotope 219 is considered as negligible. Exposure to radon varies considerably from one region to another, depending on factors such as weather conditions, and underlying geology. Activity concentration can therefore vary by a factor of 10 or even a 100 from one period of time to the next and from one area to another. There are many ways of measuring the radon 222 activity concentration and the potential alpha energy concentration of its short-lived decay products. Measuring techniques fall into three categories: - spot measurement methods; continuous measurement; integrated measurement. The proposed ISO (International Organisation for Standardisation) document suggests guidelines for measuring radon222 activity concentration and the potential alpha energy concentration of its short-lived decay products in a free (environment) and confined (buildings) atmosphere. The target date for availability of

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

    PubMed

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

    2016-10-01

    Concentrations of radon, thoron and their progeny inside the working place depend on the activity of radionuclides in the soil, building materials, atmospheric conditions, construction of the building, type of work and ventilation condition. Radon is a radioactive noble gas, and it is emanated from (226)Ra present in earth crest and building material. Based on the type of work, construction of the building and ventilation condition, concentrations of radon, thoron and their progeny have been measured in 60 workplaces at 10 locations of Mysuru, Bengaluru and Kolar districts of Karnataka state using Solid-State Nuclear Track Detector technique. From the study, variations of radon, thoron and their progeny have been observed with the nature of work.

  9. RADON MITIGATION STUDIES: NASHVILLE DEMONSTRATION

    EPA Science Inventory

    The report gives results of an EPA radon mitigation demonstration project involving 14 houses in the Nashville, TN, area with indoor radon levels of 5.6-47.6 pCi/L, using a variety of techniques, designed to be the most cost effective methods possible to implement, and yet adequa...

  10. 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.

  11. 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...

  12. Radon diffusion coefficients in soils of varying moisture content

    NASA Astrophysics Data System (ADS)

    Papachristodoulou, C.; Ioannides, K.; Pavlides, S.

    2009-04-01

    Radon is a naturally occurring radioactive gas that is generated in the Earth's crust and is free to migrate through soil and be released to the atmosphere. Due to its unique properties, soil gas radon has been established as a powerful tracer used for a variety of purposes, such as exploring uranium ores, locating geothermal resources and hydrocarbon deposits, mapping geological faults, predicting seismic activity or volcanic eruptions and testing atmospheric transport models. Much attention has also been given to the radiological health hazard posed by increased radon concentrations in the living and working environment. In order to exploit radon profiles for geophysical purposes and also to predict its entry indoors, it is necessary to study its transport through soils. Among other factors, the importance of soil moisture in such studies has been largely highlighted and it is widely accepted that any measurement of radon transport parameters should be accompanied by a measurement of the soil moisture content. In principle, validation of transport models in the field is encountered by a large number of uncontrollable and varying parameters; laboratory methods are therefore preferred, allowing for experiments to be conducted under well-specified and uniform conditions. In this work, a laboratory technique has been applied for studying the effect of soil moisture content on radon diffusion. A vertical diffusion chamber was employed, in which radon was produced from a 226Ra source, was allowed to diffuse through a soil column and was finally monitored using a silicon surface barrier detector. By solving the steady-state radon diffusion equation, diffusion coefficients (D) were determined for soil samples of varying moisture content (m), from null (m=0) to saturation (m=1). For dry soil, a D value of 4.1×10-7 m2s-1 was determined, which increased moderately by a factor of ~3 for soil with low moisture content, i.e. up to m ~0.2. At higher water fractions, a decrease

  13. Is high indoor radon concentration correlated with specific activity of radium in nearby soil? A study in Kosovo and Metohija.

    PubMed

    Gulan, Ljiljana; Stajic, Jelena M; Bochicchio, Francesco; Carpentieri, Carmela; Milic, Gordana; Nikezic, Dragoslav; Zunic, Zora S

    2017-07-05

    This paper presents indoor radon concentrations and specific activities of natural radionuclides measured in soils of Kosovo and Metohija. The measurements of radon concentration were performed during two consecutive 6-month periods in two rooms of 63 houses using CR-39 detectors. The annual radon concentration ranged from 30 to 810 Bq m(-3) with the average value of 128 Bq m(-3). Almost 15% of the houses had radon concentration higher than 200 Bq m(-3). The difference between radon concentrations measured in the two 6-month periods was analyzed, showing, as expected, a slightly higher radon concentration in the "winter period" than in the "summer period". The variation between different rooms of the same houses was also analyzed, showing that 20% of the dwellings had a significantly higher radon concentration (>100 Bq m(-3)) in one room compared to the other (the coefficient of variation ranged up to 96%). The specific activities of natural radionuclides in the nearby soil were determined by gamma spectrometry. The estimated average value (and standard deviation) of (226)Ra, (232)Th, and (40)K specific activities were 32 (13), 35 (16), and 582 (159) Bq kg(-1), respectively. The correlation between indoor (222)Rn and (226)Ra content in soil was investigated. Only a weak correlation was found (Spearman's rho = 0.220) indicating that other factors might affect diffusion and accumulation of radon indoors, as confirmed also by the high variability between the rooms of the same houses.

  14. 22 CFR 226.82 - Program income.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Program income. 226.82 Section 226.82 Foreign... ORGANIZATIONS Additional Provisions For Awards to Commercial Organizations § 226.82 Program income. The additional costs alternative described in § 226.24(b)(1) may not be applied to program income earned by...

  15. 22 CFR 226.82 - Program income.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Program income. 226.82 Section 226.82 Foreign... ORGANIZATIONS Additional Provisions For Awards to Commercial Organizations § 226.82 Program income. The additional costs alternative described in § 226.24(b)(1) may not be applied to program income earned by...

  16. 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.

  17. 230Th, 226Ra and 222Rn in abyssal sediments

    NASA Astrophysics Data System (ADS)

    Kadko, David

    1980-09-01

    A model that predicts the flux of 222Rn out of deep-sea sediment is presented. The radon is ultimately generated by 230Th which is stripped from the overlying water into the sediment. Data from many authors are compared with the model predictions. It is shown that the continental contribution of ionium is not significant, and that at low sedimentation rates, biological mixing and erosional processes strongly affect the surface concentration of the ionium. Two cores from areas of slow sediment accumulation, one from a manganese nodule region of the central Pacific and one from the Rio Grande Rise in the Atlantic were analyzed at closely spaced intervals for 230Th, 226Ra, and 210Pb. The Pacific core displayed evidence of biological mixing down to 12 cm and had a sedimentation rate of only 0.04 cm/kyr. The Atlantic core seemed to be mixed to 8 cm and had a sedimentation rate of 0.07 cm/kyr. Both cores had less total excess 230Th than predicted. Radium sediment profiles are generated from the 230Th model. Adsorbed, dissolved, and solid-phase radium is considered. According to the model, diffusional losses of radium are especially important at low sedimentation rates. Any particulate, or excess radium input is ignored in this model. The model fits the two analyzed cores if the fraction of total radium available for adsorption-desorption is about 0.5-0.7, and if K, the distribution coefficient, is about 1000. Finally, the flux of radon out of the sediments is derived from the model-generated radium profiles. It is shown that the resulting standing crop of 222Rn in the overlying water may be considered as an added constraint in budgeting 230Th and 226Ra in deep-sea sediments.

  18. Reduction of Radon Progeny in Indoor Air.

    DTIC Science & Technology

    1986-03-01

    methods that can be used to lower radon progeny concentra- tions in homes. V.- Radon in Indoor Air. Radon -222 occurs midway through the Uranium -238...as metals and remain at the site of their formation, radon is a noble gas and is thus able to diffuse away from its forma- tion site. It is through... radon progeny reduction by forced ventilation alone was evaluated because the 1/4 inch metal pre-filter screens for this air cleaner remained installed

  19. Radon emanation of rock and soil samples: A tool for stratigraphy, geology, geophysical modelling and radon health hazard

    NASA Astrophysics Data System (ADS)

    Girault, Frédéric; Koirala, Bharat P.; Bhattarai, Mukunda; Rajaure, Sudhir; Richon, Patrick; Perrier, Frédéric

    2010-05-01

    Radium-226, the mother of radon-222, with a half-life of 1600 years, is intrinsically present in all the rocks and soils in variable amount. However, a small part only of the radium atoms is able to produce radon atoms in the porous media of the rock allowing this radon to escape the rock media through the pore space. This fraction of radium is referred to as the radon source term in rocks or soils, and is usually called the effective radium concentration (ECRa). This parameter is expressed in Bq kg-1, where CRa is the radium-226 concentration and E the emanation coefficient. Considering a sample, it is not possible to estimate its ECRa value a priori. Therefore, this parameter has to be measured in the laboratory. The method in the laboratory to obtain ECRa values is based on the measurement of the concentration of radon in the inner air of a hermetically sealed container in which one rock or one soil sample was previously placed. In order to measure this radon concentration, Lucas scintillation flasks were used, and their radon content counted by a photomultiplier (Stoulos et al., Journal of Environmental Radioactivity, 2003). This method was compared in detail with another method using SSNTD (Solid-State Nuclear Track Detector). Detailed investigations have been carried out, including systematic effects such as the shape or volume of container, mass and preparation method of the sample, using a large number of rock, soil and building material samples (more than 800) collected in France and Nepal. Preliminary results will be given based on this data set. With such a large sample, some effects of intrinsic and external factors on the measurement technique and on the obtained results could also be accurately studied: the effect of atmospheric pressure, of the ambient temperature, or of the water content of the sample. ECRa measurements appear to be particularly useful for human health hazards study on a considered natural site, as well as for other applications

  20. AIR AND RADON PATHWAY MODELING FOR THE F AREA TANK FARM

    SciTech Connect

    Dixon, K.; Phifer, M.

    2010-07-30

    An air and radon pathways analysis was conducted for the F-Area Tank Farm (FTF) to estimate the flux of volatile radionuclides and radon at the ground surface due to residual waste remaining in the tanks following closure. This analysis was used as the basis to estimate the dose to the maximally exposed individual (MEI) for the air pathway per Curie (Ci) of each radionuclide remaining in the combined FTF waste tanks. For the air pathway analysis, several gaseous radionuclides were considered. These included carbon-14 (C-14), chlorine-36 (Cl-36), iodine-129 (I-129), selenium-79 (Se-79), antimony-125 (Sb-125), tin-126 (Sn-126), tritium (H-3), and technetium-99 (Tc-99). The dose to the MEI was estimated at the SRS Boundary during the 100 year institutional control period. For the 10,000 year post closure compliance period, the dose to the MEI was estimated at the 100 m compliance point. Additionally, the dose to the MEI was estimated at a seepage outcrop located 1600 m from the facility. For the radon pathway analysis, five parent radionuclides and their progeny were analyzed. These parent radionuclides included uranium-238 (U-238), plutonium-238 (Pu-238), uranium-234 (U-234), thorium-230 (Th-230), and radium-226 (Ra-226). The peak flux of radon-222 due to each parent radionuclide was estimated for the simulation period of 10,100 years.

  1. Analytical study of radionuclide concentration and radon exhalation rate in market available building materials of Ramsar

    NASA Astrophysics Data System (ADS)

    Bavarnegin, Elham; Vahabi-moghaddam, Masoud; Babakhani, Asad; Fathabadi, Nasrin

    2012-07-01

    Samples of structural and covering market available building materials from Ramsar, a northern city of Iran, were analyzed for their radon exhalation rate using an active radon gas analyzer with an emanation container. The radon exhalation rate varied from below the minimum detection limit of 0.01 to 0.31 Bq·m-2·h-1 with an average of 0.08 Bq·m-2·h-1. The 226Ra, 232Th, and 40K contents were also measured using a high resolution HPGe gamma-ray spectrometer system. The radionuclides contents varied from below the minimum detectable activity up to 73.5, 169, and 1,350 Bq.kg-1, with the average value of 16 ± 6, 25 ± 11, and 280 ± 101 Bq.kg-1, respectively. It was concluded from the results that some granite samples along with the block sample were the main source of radon exhalation rate, and the mean values of 226Ra, 232Th, and 40K in building material samples are below the world average values. Therefore, the use of these market available building materials in construction of Ramsar dwellings is considered to be safe for human habitation.

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

    PubMed

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

    1998-12-01

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

  3. 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.

  4. A source for measurement of the absolute intensities of 226Ra gamma-radiation in equilibrium with decay products.

    PubMed

    Kharitonov, I A; Rasko, M A; Sepman, S V; Terechtchenko, E E; Hejdelman, A M

    2002-01-01

    The design and production techniques of a gamma-ray spectrometric source of 226Ra in equilibrium with its daughter decay products have been developed. The radon emanation coefficient of the source did not exceed 0.1%. The 226Ra activity in the gamma-ray spectrometric source was measured relative to that in an alpha-particle spectrometric source by comparison of the intensities of the main gamma rays using a semiconductor gamma-ray spectrometer. The total uncertainty of the activity measurement results was 0.5% for a coverage factor of k = 2.

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

    PubMed

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

    2008-11-01

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

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

    PubMed

    Harvey, John A; Kearfott, Kimberlee J

    2011-11-01

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

  7. Effects of radon mitigation vs smoking cessation in reducing radon-related risk of lung cancer.

    PubMed Central

    Mendez, D; Warner, K E; Courant, P N

    1998-01-01

    OBJECTIVES: The purpose of this paper is to provide smokers with information on the relative benefits of mitigating radon and quitting smoking in reducing radon-related lung cancer risk. METHODS: The standard radon risk model, linked with models characterizing residential radon exposure and patterns of moving to new homes, was used to estimate the risk reduction produced by remediating high-radon homes, quitting smoking, or both. RESULTS: Quitting smoking reduces lung cancer risk from radon more than does reduction of radon exposure itself. CONCLUSIONS: Smokers should understand that, in addition to producing other health benefits, quitting smoking dominates strategies to deal with the problem posed by radon. PMID:9585753

  8. Passive environmental radon detector study

    SciTech Connect

    Not Available

    1992-03-01

    There are three stages at which the ambient air concentrations of radon-222 are monitored around the Uranium Mill Tailings Remedial Action (UMTRA) Project sites: before, during, and after construction. Pre-remedial-action measurements are taken for approximately 1 year. Monitoring is conducted during the entire duration of construction, and post-remedial-action monitoring is performed for approximately 1 year. Currently, the UMTRA Project uses Radtrak{reg_sign} brand alpha-track radon detectors for these environmental measurements. The purposes of radon monitoring around the UMTRA sites are (1) to determine background values around the site and pre-remedial-action conditions, (2) to control construction activities and monitor off-site releases, and (3) to compare post-remedial-action concentrations with pre-remedial-action values to demonstrate that radon concentrations have been reduced to approximately background levels. The Technical Assistance Contractor to the DOE for the UMTRA Project evaluated the performance of four different types of passive environmental radon detectors under both controlled laboratory conditions and field conditions at an unremediated UMTRA site. This study was undertaken to evaluate the accuracy and precision of four different passive, timeintegrating, environmental radon detectors in an effort to determine which brand of detector is best suited to measure environmental outdoor radon concentrations for the UMTRA Project. Voluntary manufacturer participation in the study was solicited by placing an advertisement in the Commerce Business Daily. All manufacturers participating in the study supplied the detectors and analysis free of charge.

  9. Passive environmental radon detector study

    SciTech Connect

    Not Available

    1992-03-01

    There are three stages at which the ambient air concentrations of radon-222 are monitored around the Uranium Mill Tailings Remedial Action (UMTRA) Project sites: before, during, and after construction. Pre-remedial-action measurements are taken for approximately 1 year. Monitoring is conducted during the entire duration of construction, and post-remedial-action monitoring is performed for approximately 1 year. Currently, the UMTRA Project uses Radtrak[reg sign] brand alpha-track radon detectors for these environmental measurements. The purposes of radon monitoring around the UMTRA sites are (1) to determine background values around the site and pre-remedial-action conditions, (2) to control construction activities and monitor off-site releases, and (3) to compare post-remedial-action concentrations with pre-remedial-action values to demonstrate that radon concentrations have been reduced to approximately background levels. The Technical Assistance Contractor to the DOE for the UMTRA Project evaluated the performance of four different types of passive environmental radon detectors under both controlled laboratory conditions and field conditions at an unremediated UMTRA site. This study was undertaken to evaluate the accuracy and precision of four different passive, timeintegrating, environmental radon detectors in an effort to determine which brand of detector is best suited to measure environmental outdoor radon concentrations for the UMTRA Project. Voluntary manufacturer participation in the study was solicited by placing an advertisement in the Commerce Business Daily. All manufacturers participating in the study supplied the detectors and analysis free of charge.

  10. Uranium mill tailings and radon

    SciTech Connect

    Hanchey, L A

    1981-04-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the United States may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

  11. Radon in earthquake prediction research.

    PubMed

    Friedmann, H

    2012-04-01

    The observation of anomalies in the radon concentration in soil gas and ground water before earthquakes initiated systematic investigations on earthquake precursor phenomena. The question what is needed for a meaningful earthquake prediction as well as what types of precursory effects can be expected is shortly discussed. The basic ideas of the dilatancy theory are presented which in principle can explain the occurrence of earthquake forerunners. The reasons for radon anomalies in soil gas and in ground water are clarified and a possible classification of radon anomalies is given.

  12. Intercomparison of retrospective radon detectors.

    PubMed Central

    Field, R W; Steck, D J; Parkhurst, M A; Mahaffey, J A; Alavanja, M C

    1999-01-01

    We performed both a laboratory and a field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, (210)Pb, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha-emission of a (210)Pb-decay product, (210)Po. The detector's track density generation rate (tracks per square centimeter per hour) is proportional to the surface alpha-activity. In the absence of other strong sources of alpha-emission in the glass, the implanted surface alpha-activity should be proportional to the accumulated (210)Po, and hence to the cumulative radon gas exposure. The goals of the intercomparison were to a) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, b) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass-implanted polonium activities, and c) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted (210)Po activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type

  13. Guidance on Radon Resistant Construction and Radon Mitigation

    EPA Pesticide Factsheets

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

  14. 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.

  15. Radon Risk and Remediation: A Psychological Perspective

    PubMed Central

    Hevey, David

    2017-01-01

    Although radon exposure in the home increases the risk of lung cancer, this risk can be managed. However, evidence indicates that testing for radon and subsequent home remediation rates are generally low in many countries. The present perspective outlines some key insights from psychological science that might account for sub-optimal radon protection. Psychological aspects of how the health risks posed by radon are perceived and managed are outlined. There is need to consider radon risk perception in terms of the (a) cognitive and emotional responses to radon and (b) social context in which the radon threat occurs. In addition, the nature of the threat itself is integral to the failure for people to act in response to a radon threat. Finally, the challenges arising from defensive processing of radon threat information are outlined. PMID:28396855

  16. 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.

  17. 30 CFR 57.5046 - Protection against radon gas.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Protection against radon gas. 57.5046 Section... Protection against radon gas. Where radon daughter concentrations exceed 10 WL, respirator protection against radon gas shall be provided in addition to protection against radon daughters. Protection against radon...

  18. 30 CFR 57.5046 - Protection against radon gas.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Protection against radon gas. 57.5046 Section... Protection against radon gas. Where radon daughter concentrations exceed 10 WL, respirator protection against radon gas shall be provided in addition to protection against radon daughters. Protection against radon...

  19. 30 CFR 57.5046 - Protection against radon gas.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Protection against radon gas. 57.5046 Section... Protection against radon gas. Where radon daughter concentrations exceed 10 WL, respirator protection against radon gas shall be provided in addition to protection against radon daughters. Protection against radon...

  20. 30 CFR 57.5046 - Protection against radon gas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection against radon gas. 57.5046 Section... Protection against radon gas. Where radon daughter concentrations exceed 10 WL, respirator protection against radon gas shall be provided in addition to protection against radon daughters. Protection against radon...

  1. 30 CFR 57.5046 - Protection against radon gas.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Protection against radon gas. 57.5046 Section... Protection against radon gas. Where radon daughter concentrations exceed 10 WL, respirator protection against radon gas shall be provided in addition to protection against radon daughters. Protection against radon...

  2. Radium-226-contaminated drinking water: hypothesis on an exposure pathway in a population with elevated childhood leukemia.

    PubMed

    Hoffmann, W; Kranefeld, A; Schmitz-Feuerhake, I

    1993-10-01

    A recent epidemiological survey on childhood malignant disease in the region of Ellweiler, Rheinland-Pfalz, Germany, revealed a significantly increased incidence of childhood leukemia, but observed incidences of lymphoma and solid tumors were normal. Established risk factors such as individual exposure to chemicals as well as hereditary genetic disorders were ruled out in interviews with the patients or their families. The general population in the region, however, is subjected to considerable doses of ionizing radiation due to high levels of external gamma radiation and high activities of indoor radon. Radiation-specific chromosome aberrations were found in one of two healthy siblings and one father of leukemia patients as well as in any of three probands living in houses with high indoor radon activities. Radon and natural gamma radiation, however, cannot explain the geographical pattern of the cases. Four out of seven cases were observed in two particular villages near a uranium processing plant. The drinking water of these villages partly came from a small river that was contaminated with radium-226 washed out from the dumps of the uranium plant. Only sparse measurements of 226Ra are available, but derived red bone marrow doses for children in the two villages obtained from a simple radio-ecological model show the significance of the drinking water pathway. Prenatal 226Ra exposure of fetuses due to placental transfer and accumulation may have led to significant doses and may explain the excess cases of childhood leukemia in the region even in quantitative terms.

  3. Radium-226-contaminated drinking water: hypothesis on an exposure pathway in a population with elevated childhood leukemia.

    PubMed Central

    Hoffmann, W; Kranefeld, A; Schmitz-Feuerhake, I

    1993-01-01

    A recent epidemiological survey on childhood malignant disease in the region of Ellweiler, Rheinland-Pfalz, Germany, revealed a significantly increased incidence of childhood leukemia, but observed incidences of lymphoma and solid tumors were normal. Established risk factors such as individual exposure to chemicals as well as hereditary genetic disorders were ruled out in interviews with the patients or their families. The general population in the region, however, is subjected to considerable doses of ionizing radiation due to high levels of external gamma radiation and high activities of indoor radon. Radiation-specific chromosome aberrations were found in one of two healthy siblings and one father of leukemia patients as well as in any of three probands living in houses with high indoor radon activities. Radon and natural gamma radiation, however, cannot explain the geographical pattern of the cases. Four out of seven cases were observed in two particular villages near a uranium processing plant. The drinking water of these villages partly came from a small river that was contaminated with radium-226 washed out from the dumps of the uranium plant. Only sparse measurements of 226Ra are available, but derived red bone marrow doses for children in the two villages obtained from a simple radio-ecological model show the significance of the drinking water pathway. Prenatal 226Ra exposure of fetuses due to placental transfer and accumulation may have led to significant doses and may explain the excess cases of childhood leukemia in the region even in quantitative terms. PMID:8143601

  4. 226Ra measurement in Mo, Cd and Nd 2O 3 samples with the emanation method

    NASA Astrophysics Data System (ADS)

    Barabash, A. S.; Barabanov, I. R.; Kornoukhov, V. N.; Orekhov, I. V.

    2001-08-01

    Measurements of 226Ra content in materials and chemical reagents used to construct the double beta decay sources in the NEMO-3 experiment have been done with the emanation method technique. Three different radon emanation technologies were used in these studies. The first was the "traditional" method of dissolving the sample. The second was an extraction of Rn from a melted sample and finally a technique of heating fine-grained powder was used. It is shown that there is good agreement of the data received with the emanation method and low background high purity germanium detectors. The sensitivity of this method is 0.02 mBq/ l of solution (for the "standard" emanation method) or 0.02 mBq/ kg (for methods in which radon is extracted from a powder or melt).

  5. Natural radium and radon tracers to quantify water exchange and movement in reservoirs

    USGS Publications Warehouse

    Smith, Christopher G.; Baskaran, Mark

    2011-01-01

    Radon and radium isotopes are routinely used to quantify exchange rates between different hydrologic reservoirs. Since their recognition as oceanic tracers in the 1960s, both radon and radium have been used to examine processes such as air-sea exchange, deep oceanic mixing, benthic inputs, and many others. Recently, the application of radon-222 and the radium-quartet (223,224,226,228Ra) as coastal tracers has seen a revelation with the growing interest in coastal groundwater dynamics. The enrichment of these isotopes in benthic fluids including groundwater makes both radium and radon ideal tracers of coastal benthic processes (e.g. submarine groundwater discharge). In this chapter we review traditional and recent advances in the application of radon and radium isotopes to understand mixing and exchange between various hydrologic reservoirs, specifically: (1) atmosphere and ocean, (2) deep and shallow oceanic water masses, (3) coastal groundwater/benthic pore waters and surface ocean, and (4) aquifer-lakes. While the isotopes themselves and their distribution in the environment provide qualitative information about the exchange processes, it is mixing/exchange and transport models for these isotopes that provide specific quantitative information about these processes. Brief introductions of these models and mixing parameters are provided for both historical and more recent studies.

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

    PubMed

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

    2017-03-01

    The reuse of by-products and residue streams is an important topic due to environmental and financial aspects. Manganese clay is a residue of manganese ore processing and is generated in huge amounts. This residue may contain some radionuclides with elevated concentrations. In this study, the radon emanation features and the massic exhalation rate of the heat-treated manganese clay were determined with regard to brick production. From the manganese mud depository, 20 samples were collected and after homogenization radon exhalation characteristics were determined as a function of firing temperatures from 100 to 750 °C. The major naturally occurring radionuclides (40)K, (226)Ra and (232)Th concentrations were 607 ± 34, 52 ± 6 and 40 ± 5 Bq kg(-1), respectively, comparable with normal clay samples. Similar to our previous studies a strong correlation was found between the internal structure and the radon emanation. The radon emanation coefficient decreased by ∼96% from 0.23 at 100 °C to 0.01 at 750 °C. The massic radon exhalation rate of samples fired at 750 °C reduced by 3% compared to samples fired at 100 °C. In light of the results, reusing of manganese clay as a brick additive is possible without any constraints. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

    Przylibski, T. A.

    2011-06-01

    The main factors affecting the value of 222Rn activity concentration in groundwater are the emanation coefficient of reservoir rocks (Kem), the content of parent 226Ra in these rocks (q), changes in the volume and flow velocity as well as the mixing of various groundwater components in the circulation system. The highest values of 222Rn activity concentration are recorded in groundwaters flowing towards an intake through strongly cracked reservoir rocks undergoing weathering processes. Because of these facts, waters with hazardous radon concentration levels, i.e. containing more than 100 Bq dm-3 222Rn, could be characterised in the way that follows. They are classified as radon waters, high-radon waters and extreme-radon waters. They belong to shallow circulation systems (at less than a few dozen metres below ground level) and are contemporary infiltration waters, i.e. their underground flow time ranges from several fortnights to a few decades. Because of this, these are usually poorly mineralised waters (often below 0.2-0.5 g dm-3). Their resources are renewable, but also vulnerable to contamination. Waters of this type are usually drawn from private intakes, supplying water to one or at most a few households. Due to an increased risk of developing lung tumours, radon should be removed from such waters when still in the intake. To achieve this aim, appropriate legislation should be introduced in many countries.

  8. 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.

  9. EOS7Rn—A new TOUGH2 module for simulating radon emanation and transport in the subsurface

    NASA Astrophysics Data System (ADS)

    Saâdi, Zakaria; Gay, Didier; Guillevic, Jérôme; Améon, Roselyne

    2014-04-01

    A new fluid property module, EOS7Rn, was developed for TOUGH2 to simulate the transport of radon gas (222Rn) in saturated-unsaturated soils. It is an enhanced version of the EOS7R module for radionuclide transport, with a source term added in the transport equation to model radon generation by emanation from radioactive decay of the soil radium (226Ra) content. We implemented variable physical properties (diffusion coefficient, emanation factor, adsorption coefficient, and Henry's law coefficient) of this gas component in two-phase (liquid-gas) porous media as a function of soil moisture and/or soil temperature. Numerical trials have been carried out to ensure that temporal and spatial numerical discretization of this nonlinear source term are effective and have properly been implemented in TOUGH2. We performed comparative studies between EOS7Rn and an exact analytical solution at steady-state isothermal unsaturated conditions for many numerical experiments of one-dimensional (1D) radon transport in homogeneous and layered soil columns typical of Uranium Mill Tailings (UMT) landfill soils. We found that the radon activity concentration profiles and flux densities calculated by EOS7Rn were in good agreement with the analytical solution for all the studied numerical experiments. Relative errors in radon mass balance and flux densities were determined to be negligible. For the second verification of EOS7Rn for transient nonisothermal radon transport problems, two simulation examples are presented to demonstrating the importance of the radon emanation and thermal effects on radon transport in a geothermal reservoir. Like most other sister modules, EOS7Rn can simulate nonisothermal multiphase flow and fully coupled three-dimensional transport in fractured porous media. It will help in predicting the radon exhalation from highly radium-contaminated soils and underground cavities to outdoor and indoor environments.

  10. 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.

  11. A Physician's Guide to Radon

    EPA Pesticide Factsheets

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

  12. [sup 226]Ra-[sup 230]Th disequilibrium in axial and off-axis mid-ocean ridge basalts

    SciTech Connect

    Volpe, A.M.; Goldstein, S.J. Los Alamos National Lab., NM )

    1993-03-01

    The authors describe [sup 226]Ra-[sup 230]Th disequilibrium in mid-ocean ridge basalt (MORB) glasses from the Juan de Fuca, Gorda, and East Pacific ridges. These first mass spectrometric measurements of [sup 226]Ra in MORB glasses at sub-picogram abundance levels confirm the large excesses over [sup 230]Th determined by radon-emanation techniques and alpha spectrometry. All off-axis MORB glasses have [sup 226]Ra-[sup 230]Th and [sup 234]U-[sup 238]U in secular equilibrium. This suggests that magmatic processes, not secondary post-eruption alteration, generate [sup 238]U-series disequilibrium in these MORB. Least evolved, N-MORB from axial valleys have ([sup 226]Ra/[sup 230]Th) between 2.2-2.3. Differentiated and enriched E-type MORB have consistently low ([sup 226]Ra/[sup 230]Th) ratios compared with N-MORB from the same ridge sections. Ra-Th fractionation may be less pronounced, or magma residence-transit periods may be long for differentiated MORB. Also, E-MORB may be generated by different melt extraction volumes and rates. Estimated [sup 226]Ra-[sup 230]Th ages for N-MORB agree with location on and off ridge segments, and with Th-U model ages. These preliminary results show that [sup 226]Ra-[sup 230]Th disequilibrium could be used to quantify volcanic episodicity at ocean ridges. 39 refs., 6 figs., 4 tabs.

  13. Conditioning of the 4 Curies Radium-226 Sealed Radiation Source in Thailand

    SciTech Connect

    Punnachaiya, M.; Sawangsri, T.; Wanabongse, P.; Pruantonsai, P.; Nunjan, P.; Phattanasub, A.; Ya-Anant, N.; Thiangtrongjit, S.

    2006-07-01

    This paper describes the conditioning of the 4 curies Radium-226 (Ra-226) sealed radiation source using as a teletherapy unit for cancer treatment in Thailand. The conditioning was under the International Atomic Energy Agency (IAEA) supervision and budgetary supports, comprised of 6 operational steps: the surface dose rate and actual dimension of radium unit measurements, the appropriate lead shielding design with IAEA approval, confirmation of radioactive contamination before conditioning (smear test and radon gas leakage test), transfer of radium source unit into the designed shielding, confirmation of radioactive contamination and dose rate measurement after conditioning, and transportation of Ra-226 conditioning waste package to OAP interim waste storage. The Ra-226 unit was taken out of OAP temporary waste storage for the surface dose rate and the actual dimension measurements behind the 12 inches thick heavy concrete shielding. The maximum measured surface dose rate was 70 R/hr. The special lead container was designed according to its surface dose rate along the source unit which the maximum permissible dose limit for surface dose rate of waste package after conditioning at 2 mSv/hr was applied. The IAEA approved container had total weight of 2.4 ton. After the confirmation of radioactive contamination, Ra-226 source unit was transferred and loaded in the designed lead shielding within 2 minutes. The results of smear test before and after conditioning including radon gas leakage test revealed that there was no radioactive contamination. After conditioning, the surface dose rate measured on the top, bottom were 15,10 mR/hr and varied from 6 - 50 mR/hr around lead container. The Ra-226 conditioning waste package was safely transported to store in OAP interim waste storage. Total working time including the time consumed for radon gas leakage test was 3.5 hours. The total radiation dose received by 16 operators, were ranged from 1 - 69.84 {mu}Sv and the

  14. Radon in spring waters in the south of Catalonia.

    PubMed

    Fonollosa, E; Peñalver, A; Borrull, F; Aguilar, C

    2016-01-01

    Spring waters in the south of Catalonia were analysed to determine the (222)Rn activity in order to be able to establish a correlation between the obtained values with the geology of the area of origin of these samples, and also estimate the potential health risks associated with (222)Rn. Most of the analysed samples (90%) show (222)Rn activities lower than 100Bq/L (exposure limit in water recommended by the World Health Organisation and EU directive 2013/51/EURATOM). However, in some cases, the activity values found for this isotope exceeded those levels and this can be attributed to the geology of the area where the spring waters are located, which is predominantly of granitic characteristics. To verify the origin of the radon present in the analysed samples, the obtained activity values were compared with the activities of its parents ((226)Ra, (238)U and (234)U). Finally, we have calculated the annual effective dose from all the radionuclides measured in spring water samples. The results showed that the higher contribution due to spring water ingestion come from (222)Rn and (226)Ra. The resulting contribution to the annual effective dose due to radon ingestion varies between 10.2 and 765.8 μSv/y, and the total annual effective dose due to his parents, (226)Ra, (234)U and (238)U varies between 0.8 and 21.2 μSv/y so the consumption of these waters does not involve any risks to population due to its natural radioactivity content.

  15. Measurement of 224Ra and 225Ra activities in natural waters using a radon-in-air monitor.

    PubMed

    Kim, G; Burnett, W C; Dulaiova, H; Swarzenski, P W; Moore, W S

    2001-12-01

    We report a simple new technique for measuring low-level radium isotopes (224Ra and 226Ra) in natural waters. The radium present in natural waters is first preconcentrated onto MnO2-coated acrylic fiber (Mn fiber) in a column mode. The radon produced from the adsorbed radium is then circulated through a closed air-loop connected to a commercial radon-in-air monitor. The monitor counts alpha decays of radon daughters (polonium isotopes) which are electrostatically collected onto a silicon semiconductor detector. Count data are collected in energy-specific windows, which eliminate interference and maintain very low backgrounds. Radium-224 is measured immediately after sampling via 220Rn (216Po), and 226Ra is measured via 222Rn 218Po) after a few days of ingrowth of 222Rn. This technique is rapid, simple, and accurate for measurements of low-level 224Ra and 226Ra activities without requiring any wet chemistry. Rapid measurements of short-lived 222Rn and 224Ra, along with long-lived 226Ra, may thus be made in natural waters using a single portable system for environmental monitoring of radioactivity as well as tracing of various geochemical and geophysical processes. The technique could be especially useful for the on-site rapid determination of 224Ra which has recently been found to occur at elevated activities in some groundwater wells.

  16. Radon recording of Uttarkashi earthquake

    NASA Astrophysics Data System (ADS)

    Virk, H. S.; Singh, Baljinder

    1994-04-01

    Spatial and temporal distribution of radon is recorded in both soil-gas and groundwater using two different techniques, viz. track etch method and emanometry. Radon recording stations have been set up at one site in Amritsar and four sites in the Kangra valley (Himachal Pradesh) under the Himalayan seismicity project. The track-etch method gives integrated measurement of radon over a week or a fortnight whereas emanometry is used for daily recording of radon activity in soil-gas and groundwater. The Uttarkashi earthquake m(sub b) = 6.5, M(sub S) = 7.0) occurred on October 20, 1991 (Oct. 19 U.T.) in the Garhwal Himalayas (30.78 deg N, 78.77 deg E) about 330 km from our recording stations in the Kangra valley and about 450 km from Amritsar, respectively. Radon anomalies were recorded at all sites in Kangra valley and Amritsar about a week before the Uttarkashi earthquke, which clearly establishes that radon changes can be effective for forecasting some earthquakes.

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

    PubMed

    Foster, Stephanie; Everett Jones, Sherry

    2016-12-13

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

  18. 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

  19. 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.

  20. 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.

  1. 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...

  2. 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...

  3. 48 CFR 226.370-2 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Universities and Minority Institutions 226.370-2 Definitions. Definitions of HBCUs and MIs are in the clause at 252.226-7000, Notice of Historically Black College or University and Minority Institution Set-Aside....

  4. 48 CFR 226.370-2 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Universities and Minority Institutions 226.370-2 Definitions. Definitions of HBCUs and MIs are in the clause at 252.226-7000, Notice of Historically Black College or University and Minority Institution Set-Aside....

  5. 48 CFR 226.370-2 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Universities and Minority Institutions 226.370-2 Definitions. Definitions of HBCUs and MIs are in the clause at 252.226-7000, Notice of Historically Black College or University and Minority Institution Set-Aside....

  6. 48 CFR 226.370-2 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Universities and Minority Institutions 226.370-2 Definitions. Definitions of HBCUs and MIs are in the clause at 252.226-7000, Notice of Historically Black College or University and Minority Institution Set-Aside....

  7. 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.

  8. Highly sensitive radon monitor and radon emanation rates for detector components

    NASA Astrophysics Data System (ADS)

    Choi, E.; Komori, M.; Takahisa, K.; Kudomi, N.; Kume, K.; Hayashi, K.; Yoshida, S.; Ohsumi, H.; Ejiri, H.; Kishimoto, T.; Matsuoka, K.; Tasaka, S.

    2001-02-01

    The radon emanation rates for materials were measured by using the electrostatic precipitation method as a radon monitor. It was found that a low level of radon was emanated from several material components in ELEGANT V. The radon monitor has been developed for the highly sensitive measurements of low-level radon concentration. The system was shown to have a sensitivity to radon concentrations as low as 1.6 mBq/ m3 for one day measurement. The system was also used as the radon concentration monitor for the gas inside the airtight box of the ELEGANT V at Oto Cosmo Observatory.

  9. Surface-water radon-222 distribution along the west-central Florida shelf

    USGS Publications Warehouse

    Smith, C.G.; Robbins, L.L.

    2012-01-01

    In February 2009 and August 2009, the spatial distribution of radon-222 in surface water was mapped along the west-central Florida shelf as collaboration between the Response of Florida Shelf Ecosystems to Climate Change project and a U.S. Geological Survey Mendenhall Research Fellowship project. This report summarizes the surface distribution of radon-222 from two cruises and evaluates potential physical controls on radon-222 fluxes. Radon-222 is an inert gas produced overwhelmingly in sediment and has a short half-life of 3.8 days; activities in surface water ranged between 30 and 170 becquerels per cubic meter. Overall, radon-222 activities were enriched in nearshore surface waters relative to offshore waters. Dilution in offshore waters is expected to be the cause of the low offshore activities. While thermal stratification of the water column during the August survey may explain higher radon-222 activities relative to the February survey, radon-222 activity and integrated surface-water inventories decreased exponentially from the shoreline during both cruises. By estimating radon-222 evasion by wind from nearby buoy data and accounting for internal production from dissolved radium-226, its radiogenic long-lived parent, a simple one-dimensional model was implemented to determine the role that offshore mixing, benthic influx, and decay have on the distribution of excess radon-222 inventories along the west Florida shelf. For multiple statistically based boundary condition scenarios (first quartile, median, third quartile, and maximum radon-222 inshore of 5 kilometers), the cross-shelf mixing rates and average nearshore submarine groundwater discharge (SGD) rates varied from 100.38 to 10-3.4 square kilometers per day and 0.00 to 1.70 centimeters per day, respectively. This dataset and modeling provide the first attempt to assess cross-shelf mixing and SGD on such a large spatial scale. Such estimates help scale up SGD rates that are often made at 1- to 10-meter

  10. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. 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.

  12. Thermo-diffusional radon waves in soils.

    PubMed

    Minkin, Leonid; Shapovalov, Alexander S

    2016-09-15

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

  13. EPA recommends radon testing in January

    EPA Pesticide Factsheets

    PHILADELPHIA (January 8, 2015) - The U.S. Environmental Protection Agency has designated January as national Radon Action Month, a perfect time for you to protect your family by testing your home for radon.

  14. Final Federal Radon Action Plan Scorecard

    EPA Pesticide Factsheets

    This page provides information and a link to the draft Federal Radon Action Plan. It also contains a Federal Radon Action Plan Scorecard, a tool designed to display the current status of each federal agency commitments and outcomes to date.

  15. Radon concentrations in kindergartens and schools in two cities: Kalisz and Ostrów Wielkopolski in Poland.

    PubMed

    Bem, Henryk; Bem, Ewa Maria; Krawczyk, Joanna; Płotek, Marcin; Janiak, Sławomira; Mazurek, Daria

    Plastic PicoRad detectors with activated charcoal have been used for radon monitoring in local kindergartens and schools in two cities, Kalisz and Ostrów Wielkopolski, in the region of Greater Poland. Detectors were exposed for a standard time of 48 h during the autumn and winter of 2011 in 103 rooms (Kalisz) and 55 rooms (Ostrów Wlkp), respectively. The detectors were calibrated in the certified radon chamber of the Central Laboratory for Radiological Protection in Warsaw, Poland. The arithmetic and geometric means of indoor radon concentrations in the examined rooms were 46.0 and 30.3 Bq/m(3) for Kalisz and 48.9 and 29.8 Bq/m(3) for Ostrów Wlkp, respectively. The measured levels of the indoor radon concentrations were relatively low, since the main source of indoor radon for these low storey (max. three storeys) buildings is radon escaping from the underlying soil with a low (226)Ra concentration (~15 Bq/m(3)). Therefore, the calculated annual effective doses from that source for the children in Kalisz and Ostrów Wlkp were also low 0.35 mSv.

  16. 7 CFR 226.8 - Audits.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Audits. 226.8 Section 226.8 Agriculture Regulations of... NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM State Agency Provisions § 226.8 Audits. (a) Unless otherwise exempt, audits at the State and institution levels must be conducted in accordance with Office of...

  17. 25 CFR 226.36 - Control devices.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Control devices. 226.36 Section 226.36 Indians BUREAU OF... AND GAS MINING Requirements of Lessees § 226.36 Control devices. In drilling operations in fields... operations to maintain proper control of subsurface strata....

  18. 1 CFR 22.6 - Code designation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true Code designation. 22.6 Section 22.6 General... DOCUMENTS PREPARATION OF NOTICES AND PROPOSED RULES Proposed Rules § 22.6 Code designation. The area of the Code of Federal Regulations directly affected by a proposed regulatory action shall be identified by...

  19. 1 CFR 22.6 - Code designation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Code designation. 22.6 Section 22.6 General... DOCUMENTS PREPARATION OF NOTICES AND PROPOSED RULES Proposed Rules § 22.6 Code designation. The area of the Code of Federal Regulations directly affected by a proposed regulatory action shall be identified by...

  20. 1 CFR 22.6 - Code designation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Code designation. 22.6 Section 22.6 General... DOCUMENTS PREPARATION OF NOTICES AND PROPOSED RULES Proposed Rules § 22.6 Code designation. The area of the Code of Federal Regulations directly affected by a proposed regulatory action shall be identified by...

  1. 1 CFR 22.6 - Code designation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true Code designation. 22.6 Section 22.6 General... DOCUMENTS PREPARATION OF NOTICES AND PROPOSED RULES Proposed Rules § 22.6 Code designation. The area of the Code of Federal Regulations directly affected by a proposed regulatory action shall be identified by...

  2. 32 CFR 226.3 - Policy.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Policy. 226.3 Section 226.3 National Defense... THE HOMELESS § 226.3 Policy. (a) By Memorandum for the Secretaries of the Military Departments from... Secretary of Defense stated it is Department of Defense policy that shelters for the homeless may be...

  3. 12 CFR 226.4 - Finance charge.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Finance charge. 226.4 Section 226.4 Banks and... LENDING (REGULATION Z) General § 226.4 Finance charge. (a) Definition. The finance charge is the cost of...) Charges by third parties. The finance charge includes fees and amounts charged by someone other than the...

  4. 7 CFR 226.3 - Administration.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Administration. 226.3 Section 226.3 Agriculture... CHILD NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM General § 226.3 Administration. (a) Within the Department, FNS shall act on behalf of the Department in the administration of the Program. (b...

  5. 21 CFR 226.58 - Laboratory controls.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Laboratory controls. 226.58 Section 226.58 Food...: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES Product Quality Control § 226.58 Laboratory controls. Laboratory controls shall include the establishment of adequate specifications and test...

  6. 22 CFR 226.52 - Financial reporting.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Financial reporting. 226.52 Section 226.52...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Reports and Records § 226.52 Financial reporting. USAID requires recipients to use the Standard Form 425 or Standard Form 425a, Federal Financial Report, or...

  7. 25 CFR 226.36 - Control devices.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Control devices. 226.36 Section 226.36 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Requirements of Lessees § 226.36 Control devices. In drilling operations in fields...

  8. 12 CFR 226.25 - Record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 3 2013-01-01 2013-01-01 false Record retention. 226.25 Section 226.25 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM (CONTINUED) TRUTH IN LENDING (REGULATION Z) Miscellaneous § 226.25 Record retention. (a) General rule. A...

  9. 12 CFR 226.25 - Record retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Record retention. 226.25 Section 226.25 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Miscellaneous § 226.25 Record retention. (a) General rule. A creditor shall...

  10. 32 CFR 226.2 - Applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 2 2014-07-01 2014-07-01 false Applicability. 226.2 Section 226.2 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.2 Applicability. This part applies to the Office of the Secretary...

  11. 32 CFR 226.2 - Applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 2 2013-07-01 2013-07-01 false Applicability. 226.2 Section 226.2 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.2 Applicability. This part applies to the Office of the Secretary...

  12. 32 CFR 226.3 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 2 2014-07-01 2014-07-01 false 226.3 Section 226.3 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.3...

  13. 32 CFR 226.2 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Applicability. 226.2 Section 226.2 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.2 Applicability. This part applies to the Office of the Secretary...

  14. 32 CFR 226.2 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 2 2012-07-01 2012-07-01 false Applicability. 226.2 Section 226.2 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.2 Applicability. This part applies to the Office of the Secretary...

  15. 32 CFR 226.2 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 2 2011-07-01 2011-07-01 false Applicability. 226.2 Section 226.2 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.2 Applicability. This part applies to the Office of the Secretary...

  16. 32 CFR 226.3 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 2 2013-07-01 2013-07-01 false 226.3 Section 226.3 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.3...

  17. 21 CFR 226.20 - Buildings.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... of containers, packaging materials, labeling, and finished products. (5) Control laboratory... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Buildings. 226.20 Section 226.20 Food and Drugs... Facilities and Equipment § 226.20 Buildings. Buildings in which Type A medicated article(s) are...

  18. 21 CFR 226.20 - Buildings.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... of containers, packaging materials, labeling, and finished products. (5) Control laboratory... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Buildings. 226.20 Section 226.20 Food and Drugs... Facilities and Equipment § 226.20 Buildings. Buildings in which Type A medicated article(s) are...

  19. 25 CFR 226.36 - Control devices.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Control devices. 226.36 Section 226.36 Indians BUREAU OF... AND GAS MINING Requirements of Lessees § 226.36 Control devices. In drilling operations in fields... operations to maintain proper control of subsurface strata. ...

  20. 21 CFR 226.58 - Laboratory controls.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Laboratory controls. 226.58 Section 226.58 Food...: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES Product Quality Control § 226.58 Laboratory controls. Laboratory controls shall include the establishment of adequate specifications and test...

  1. 21 CFR 226.58 - Laboratory controls.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Laboratory controls. 226.58 Section 226.58 Food...: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES Product Quality Control § 226.58 Laboratory controls. Laboratory controls shall include the establishment of adequate specifications and test...

  2. 34 CFR 303.226 - Fiscal control.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 34 Education 2 2013-07-01 2013-07-01 false Fiscal control. 303.226 Section 303.226 Education... DISABILITIES State Application and Assurances Assurances § 303.226 Fiscal control. The State must ensure that fiscal control and fund accounting procedures will be adopted as necessary to ensure proper disbursement...

  3. 21 CFR 226.58 - Laboratory controls.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Laboratory controls. 226.58 Section 226.58 Food...: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES Product Quality Control § 226.58 Laboratory controls. Laboratory controls shall include the establishment of adequate specifications and test...

  4. 32 CFR 226.4 - Responsibilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Responsibilities. 226.4 Section 226.4 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR THE HOMELESS § 226.4 Responsibilities. (a) The Deputy Assistant Secretary of...

  5. 12 CFR 226.29 - State exemptions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false State exemptions. 226.29 Section 226.29 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Miscellaneous § 226.29 State exemptions. (a) General rule. Any State may...

  6. 12 CFR 226.25 - Record retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Record retention. 226.25 Section 226.25 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Miscellaneous § 226.25 Record retention. (a) General rule. A creditor shall...

  7. 7 CFR 226.8 - Audits.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Audits. 226.8 Section 226.8 Agriculture Regulations of... NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM State Agency Provisions § 226.8 Audits. (a) Unless otherwise exempt, audits at the State and institution levels must be conducted in accordance with Office...

  8. 25 CFR 226.33 - Line drilling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Line drilling. 226.33 Section 226.33 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Requirements of Lessees § 226.33 Line drilling. Lessee shall not drill within 300 feet...

  9. 25 CFR 226.33 - Line drilling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Line drilling. 226.33 Section 226.33 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Requirements of Lessees § 226.33 Line drilling. Lessee shall not drill within 300 feet...

  10. 25 CFR 226.33 - Line drilling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Line drilling. 226.33 Section 226.33 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Requirements of Lessees § 226.33 Line drilling. Lessee shall not drill within 300 feet...

  11. 25 CFR 226.33 - Line drilling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Line drilling. 226.33 Section 226.33 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Requirements of Lessees § 226.33 Line drilling. Lessee shall not drill within 300 feet...

  12. 30 CFR 22.6 - General requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false General requirements. 22.6 Section 22.6 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS PORTABLE METHANE DETECTORS § 22.6 General requirements. Methane detectors approved...

  13. 30 CFR 22.6 - General requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false General requirements. 22.6 Section 22.6 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS PORTABLE METHANE DETECTORS § 22.6 General requirements. Methane detectors approved...

  14. 7 CFR 226.25 - Other provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Other provisions. 226.25 Section 226.25 Agriculture... CHILD NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM Other Provisions § 226.25 Other provisions..., steals, or obtains by fraud any funds, assets, or property that are the subject of a grant or other...

  15. 31 CFR 226.7 - Effective date.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Effective date. 226.7 Section 226.7 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE... LOAN DEPOSITARIES § 226.7 Effective date. The provisions of this part become effective November 2, 1978....

  16. 29 CFR 553.226 - Training time.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Training time. 553.226 Section 553.226 Labor Regulations... Enforcement Employees of Public Agencies Tour of Duty and Compensable Hours of Work Rules § 553.226 Training time. (a) The general rules for determining the compensability of training time under the FLSA are set...

  17. 22 CFR 226.43 - Competition.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Competition. 226.43 Section 226.43 Foreign... ORGANIZATIONS Post-award Requirements Procurement Standards § 226.43 Competition. All procurement transactions shall be conducted in a manner to provide, to the maximum extent practical, open and free...

  18. 22 CFR 226.43 - Competition.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Competition. 226.43 Section 226.43 Foreign... ORGANIZATIONS Post-award Requirements Procurement Standards § 226.43 Competition. All procurement transactions shall be conducted in a manner to provide, to the maximum extent practical, open and free...

  19. 22 CFR 226.43 - Competition.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Competition. 226.43 Section 226.43 Foreign... ORGANIZATIONS Post-award Requirements Procurement Standards § 226.43 Competition. All procurement transactions shall be conducted in a manner to provide, to the maximum extent practical, open and free...

  20. 30 CFR 22.6 - General requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false General requirements. 22.6 Section 22.6 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS PORTABLE METHANE DETECTORS § 22.6 General requirements. Methane detectors approved under...

  1. 30 CFR 22.6 - General requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false General requirements. 22.6 Section 22.6 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS PORTABLE METHANE DETECTORS § 22.6 General requirements. Methane detectors approved under...

  2. 30 CFR 22.6 - General requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false General requirements. 22.6 Section 22.6 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS PORTABLE METHANE DETECTORS § 22.6 General requirements. Methane detectors approved under...

  3. 21 CFR 226.20 - Buildings.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Buildings. 226.20 Section 226.20 Food and Drugs... Facilities and Equipment § 226.20 Buildings. Buildings in which Type A medicated article(s) are manufactured... operation for their intended purpose. The building shall: (a) Provide adequate space for the orderly...

  4. 22 CFR 226.31 - Insurance coverage.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Insurance coverage. 226.31 Section 226.31...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.31 Insurance coverage. Recipients shall, at a minimum, provide the equivalent insurance coverage for real property and equipment...

  5. 22 CFR 226.31 - Insurance coverage.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Insurance coverage. 226.31 Section 226.31...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.31 Insurance coverage. Recipients shall, at a minimum, provide the equivalent insurance coverage for real property and equipment...

  6. 22 CFR 226.31 - Insurance coverage.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Insurance coverage. 226.31 Section 226.31...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.31 Insurance coverage. Recipients shall, at a minimum, provide the equivalent insurance coverage for real property and equipment...

  7. 22 CFR 226.43 - Competition.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Competition. 226.43 Section 226.43 Foreign... ORGANIZATIONS Post-award Requirements Procurement Standards § 226.43 Competition. All procurement transactions shall be conducted in a manner to provide, to the maximum extent practical, open and free...

  8. 22 CFR 226.52 - Financial reporting.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Financial reporting. 226.52 Section 226.52 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Reports and Records § 226.52 Financial reporting....

  9. 22 CFR 226.62 - Enforcement.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Enforcement. 226.62 Section 226.62 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Suspension, Termination and Enforcement § 226.62 Enforcement. (a)...

  10. 22 CFR 226.36 - Intangible property.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Intangible property. 226.36 Section 226.36 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.36 Intangible property. (a)...

  11. 22 CFR 226.62 - Enforcement.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Enforcement. 226.62 Section 226.62 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Suspension, Termination and Enforcement § 226.62 Enforcement. (a)...

  12. 22 CFR 226.24 - Program income.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Program income. 226.24 Section 226.24 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.24 Program income. (a)...

  13. 22 CFR 226.36 - Intangible property.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Intangible property. 226.36 Section 226.36 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.36 Intangible property. (a)...

  14. 22 CFR 226.24 - Program income.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Program income. 226.24 Section 226.24 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.24 Program income. (a)...

  15. 22 CFR 226.46 - Procurement records.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Procurement records. 226.46 Section 226.46 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.46 Procurement...

  16. 22 CFR 226.32 - Real property.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Real property. 226.32 Section 226.32 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.32 Real property. (a) Unless the...

  17. 22 CFR 226.41 - Recipient responsibilities.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Recipient responsibilities. 226.41 Section 226.41 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.41...

  18. 22 CFR 226.52 - Financial reporting.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Financial reporting. 226.52 Section 226.52 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Reports and Records § 226.52 Financial reporting....

  19. 22 CFR 226.46 - Procurement records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Procurement records. 226.46 Section 226.46 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.46 Procurement...

  20. 22 CFR 226.47 - Contract administration.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Contract administration. 226.47 Section 226.47 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.47 Contract administration....

  1. 22 CFR 226.41 - Recipient responsibilities.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Recipient responsibilities. 226.41 Section 226.41 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.41...

  2. 22 CFR 226.47 - Contract administration.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Contract administration. 226.47 Section 226.47 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.47 Contract administration....

  3. 22 CFR 226.34 - Equipment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Equipment. 226.34 Section 226.34 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.34 Equipment. (a) Unless the agreement...

  4. 22 CFR 226.62 - Enforcement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Enforcement. 226.62 Section 226.62 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Suspension, Termination and Enforcement § 226.62 Enforcement. (a)...

  5. 22 CFR 226.46 - Procurement records.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Procurement records. 226.46 Section 226.46 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.46 Procurement...

  6. 22 CFR 226.46 - Procurement records.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Procurement records. 226.46 Section 226.46 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.46 Procurement...

  7. 22 CFR 226.62 - Enforcement.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Enforcement. 226.62 Section 226.62 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Suspension, Termination and Enforcement § 226.62 Enforcement. (a)...

  8. 22 CFR 226.34 - Equipment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Equipment. 226.34 Section 226.34 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.34 Equipment. (a) Unless the agreement...

  9. 22 CFR 226.32 - Real property.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Real property. 226.32 Section 226.32 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.32 Real property. (a) Unless the...

  10. 22 CFR 226.46 - Procurement records.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Procurement records. 226.46 Section 226.46 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.46 Procurement...

  11. 22 CFR 226.34 - Equipment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Equipment. 226.34 Section 226.34 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.34 Equipment. (a) Unless the agreement...

  12. 22 CFR 226.41 - Recipient responsibilities.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Recipient responsibilities. 226.41 Section 226.41 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.41...

  13. 22 CFR 226.36 - Intangible property.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Intangible property. 226.36 Section 226.36 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.36 Intangible property. (a)...

  14. 22 CFR 226.47 - Contract administration.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Contract administration. 226.47 Section 226.47 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.47 Contract administration....

  15. 22 CFR 226.62 - Enforcement.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Enforcement. 226.62 Section 226.62 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Suspension, Termination and Enforcement § 226.62 Enforcement. (a)...

  16. 22 CFR 226.47 - Contract administration.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Contract administration. 226.47 Section 226.47 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.47 Contract administration....

  17. 22 CFR 226.24 - Program income.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Program income. 226.24 Section 226.24 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.24 Program income. (a)...

  18. 22 CFR 226.32 - Real property.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Real property. 226.32 Section 226.32 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.32 Real property. (a) Unless the...

  19. 22 CFR 226.47 - Contract administration.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Contract administration. 226.47 Section 226.47 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.47 Contract administration....

  20. 21 CFR 226.10 - Personnel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Personnel. 226.10 Section 226.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES General Provisions § 226.10 Personnel...

  1. 22 CFR 226.22 - Payment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Payment. 226.22 Section 226.22 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.22 Payment. (a) Payment methods...

  2. 22 CFR 226.22 - Payment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 1 2012-04-01 2012-04-01 false Payment. 226.22 Section 226.22 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.22 Payment. (a) Payment methods...

  3. 22 CFR 226.22 - Payment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Payment. 226.22 Section 226.22 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.22 Payment. (a) Payment methods...

  4. 7 CFR 226.8 - Audits.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 4 2013-01-01 2013-01-01 false Audits. 226.8 Section 226.8 Agriculture Regulations of... NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM State Agency Provisions § 226.8 Audits. (a) Unless otherwise exempt, audits at the State and institution levels must be conducted in accordance with Office...

  5. 7 CFR 226.8 - Audits.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Audits. 226.8 Section 226.8 Agriculture Regulations of... NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM State Agency Provisions § 226.8 Audits. (a) Unless otherwise exempt, audits at the State and institution levels must be conducted in accordance with Office...

  6. 7 CFR 226.8 - Audits.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 4 2012-01-01 2012-01-01 false Audits. 226.8 Section 226.8 Agriculture Regulations of... NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM State Agency Provisions § 226.8 Audits. (a) Unless otherwise exempt, audits at the State and institution levels must be conducted in accordance with Office...

  7. 12 CFR 226.16 - Advertising.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 3 2014-01-01 2014-01-01 false Advertising. 226.16 Section 226.16 Banks and...) TRUTH IN LENDING (REGULATION Z) Open-End Credit § 226.16 Advertising. (a) Actually available terms. If... periodic payment amount advertised. The disclosure of the total of payments and the time period to...

  8. 12 CFR 226.24 - Advertising.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Advertising. 226.24 Section 226.24 Banks and... LENDING (REGULATION Z) Closed-End Credit § 226.24 Advertising. (a) Actually available terms. If an... annual rate of interest will apply over the term of the advertised loan, the advertisement shall...

  9. 12 CFR 226.16 - Advertising.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 3 2012-01-01 2012-01-01 false Advertising. 226.16 Section 226.16 Banks and... LENDING (REGULATION Z) Open-End Credit § 226.16 Advertising. (a) Actually available terms. If an... periodic payment amount advertised. The disclosure of the total of payments and the time period to...

  10. 12 CFR 226.24 - Advertising.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 3 2014-01-01 2014-01-01 false Advertising. 226.24 Section 226.24 Banks and...) TRUTH IN LENDING (REGULATION Z) Closed-End Credit § 226.24 Advertising. (a) Actually available terms. If... annual rate of interest will apply over the term of the advertised loan, the advertisement shall...

  11. 12 CFR 226.24 - Advertising.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 3 2012-01-01 2012-01-01 false Advertising. 226.24 Section 226.24 Banks and... LENDING (REGULATION Z) Closed-End Credit § 226.24 Advertising. (a) Actually available terms. If an... annual rate of interest will apply over the term of the advertised loan, the advertisement shall...

  12. 12 CFR 226.16 - Advertising.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 3 2013-01-01 2013-01-01 false Advertising. 226.16 Section 226.16 Banks and...) TRUTH IN LENDING (REGULATION Z) Open-End Credit § 226.16 Advertising. (a) Actually available terms. If... periodic payment amount advertised. The disclosure of the total of payments and the time period to...

  13. 12 CFR 226.24 - Advertising.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 3 2013-01-01 2013-01-01 false Advertising. 226.24 Section 226.24 Banks and...) TRUTH IN LENDING (REGULATION Z) Closed-End Credit § 226.24 Advertising. (a) Actually available terms. If... annual rate of interest will apply over the term of the advertised loan, the advertisement shall...

  14. 21 CFR 226.42 - Components.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Components. 226.42 Section 226.42 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES Product Quality Control § 226.42...

  15. 22 CFR 226.24 - Program income.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Program income. 226.24 Section 226.24 Foreign... ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.24 Program income. (a) Recipients shall apply the standards set forth in this section to account for program income related to...

  16. 22 CFR 226.24 - Program income.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Program income. 226.24 Section 226.24 Foreign... ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.24 Program income. (a) Recipients shall apply the standards set forth in this section to account for program income related to...

  17. 22 CFR 226.71 - Closeout procedures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Closeout procedures. 226.71 Section 226.71 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS After-the-Award Requirements § 226.71 Closeout procedures. (a) Recipients shall...

  18. 22 CFR 226.90 - Disputes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Disputes. 226.90 Section 226.90 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Miscellaneous § 226.90 Disputes. (a) Any dispute under or relating to a grant or agreement shall...

  19. 22 CFR 226.31 - Insurance coverage.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Insurance coverage. 226.31 Section 226.31...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.31 Insurance coverage. Recipients shall, at a minimum, provide the equivalent insurance coverage for real property and equipment...

  20. 22 CFR 226.31 - Insurance coverage.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Insurance coverage. 226.31 Section 226.31...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Property Standards § 226.31 Insurance coverage. Recipients shall, at a minimum, provide the equivalent insurance coverage for real property and equipment...

  1. 7 CFR 4279.226 - Fees.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Fees. 4279.226 Section 4279.226 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE SERVICE AND RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED LOANMAKING Biorefinery Assistance Loans § 4279.226...

  2. 7 CFR 4279.226 - Fees.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 15 2012-01-01 2012-01-01 false Fees. 4279.226 Section 4279.226 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE SERVICE AND RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED LOANMAKING Biorefinery Assistance Loans § 4279.226...

  3. 7 CFR 4279.226 - Fees.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Fees. 4279.226 Section 4279.226 Agriculture Regulations of the Department of Agriculture (Continued) RURAL BUSINESS-COOPERATIVE SERVICE AND RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE GUARANTEED LOANMAKING Biorefinery Assistance Loans § 4279.226...

  4. 13 CFR 134.226 - The decision.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false The decision. 134.226 Section 134.226 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION RULES OF PROCEDURE GOVERNING CASES BEFORE THE OFFICE OF HEARINGS AND APPEALS Rules of Practice for Most Cases § 134.226 The decision....

  5. 31 CFR 226.6 - Financial reports.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false Financial reports. 226.6 Section 226.6..., DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE RECOGNITION OF INSURANCE COVERING TREASURY TAX AND LOAN DEPOSITARIES § 226.6 Financial reports. Financial reports of Insurance Organizations shall...

  6. 31 CFR 226.6 - Financial reports.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Financial reports. 226.6 Section 226..., DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE RECOGNITION OF INSURANCE COVERING TREASURY TAX AND LOAN DEPOSITARIES § 226.6 Financial reports. Financial reports of Insurance Organizations shall...

  7. 22 CFR 226.52 - Financial reporting.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 1 2013-04-01 2013-04-01 false Financial reporting. 226.52 Section 226.52...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Reports and Records § 226.52 Financial reporting. USAID requires recipients to use the Standard Form 425 or Standard Form 425a, Federal Financial Report, or...

  8. 31 CFR 226.6 - Financial reports.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Financial reports. 226.6 Section 226.6..., DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE RECOGNITION OF INSURANCE COVERING TREASURY TAX AND LOAN DEPOSITARIES § 226.6 Financial reports. Financial reports of Insurance Organizations shall...

  9. 22 CFR 226.52 - Financial reporting.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 1 2014-04-01 2014-04-01 false Financial reporting. 226.52 Section 226.52...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Reports and Records § 226.52 Financial reporting. USAID requires recipients to use the Standard Form 425 or Standard Form 425a, Federal Financial Report, or...

  10. 31 CFR 226.6 - Financial reports.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false Financial reports. 226.6 Section 226.6..., DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE RECOGNITION OF INSURANCE COVERING TREASURY TAX AND LOAN DEPOSITARIES § 226.6 Financial reports. Financial reports of Insurance Organizations shall...

  11. 12 CFR 226.4 - Finance charge.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 3 2012-01-01 2012-01-01 false Finance charge. 226.4 Section 226.4 Banks and... LENDING (REGULATION Z) General § 226.4 Finance charge. (a) Definition. The finance charge is the cost of...) Charges by third parties. The finance charge includes fees and amounts charged by someone other than...

  12. 12 CFR 226.4 - Finance charge.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 3 2013-01-01 2013-01-01 false Finance charge. 226.4 Section 226.4 Banks and...) TRUTH IN LENDING (REGULATION Z) General § 226.4 Finance charge. (a) Definition. The finance charge is... transaction. (1) Charges by third parties. The finance charge includes fees and amounts charged by...

  13. 12 CFR 226.4 - Finance charge.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 3 2014-01-01 2014-01-01 false Finance charge. 226.4 Section 226.4 Banks and...) TRUTH IN LENDING (REGULATION Z) General § 226.4 Finance charge. (a) Definition. The finance charge is... transaction. (1) Charges by third parties. The finance charge includes fees and amounts charged by...

  14. 29 CFR 553.226 - Training time.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Training time. 553.226 Section 553.226 Labor Regulations... Enforcement Employees of Public Agencies Tour of Duty and Compensable Hours of Work Rules § 553.226 Training time. (a) The general rules for determining the compensability of training time under the FLSA are...

  15. 25 CFR 226.33 - Line drilling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Line drilling. 226.33 Section 226.33 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR ENERGY AND MINERALS LEASING OF OSAGE RESERVATION LANDS FOR OIL AND GAS MINING Requirements of Lessees § 226.33 Line drilling. Lessee shall not drill within 300...

  16. 22 CFR 226.44 - Procurement procedures.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 1 2011-04-01 2011-04-01 false Procurement procedures. 226.44 Section 226.44...-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Procurement Standards § 226.44 Procurement procedures. (a) All recipients shall establish written procurement procedures. These procedures shall provide, at a...

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

    PubMed

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

    2015-02-01

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

  18. Factors affecting atmospheric radon concentration, human health.

    PubMed

    Tchorz-Trzeciakiewicz, D E; Kłos, M

    2017-04-15

    We studied the influence of terrain, geology and weather condition on radon concentration in the atmosphere and occurrence of radon density currents. The survey was carried out in Kowary (SW Poland) and in the spoil tip formed during uranium mining. The measurements of radon concentration were performed using SSNTD LR-115. The measurements of uranium thorium and potassium content in soil were carried out using gamma ray spectrometer Exploranium RS-230. We noticed that terrain and stability of weather condition had significant impact on atmospheric radon concentration. The seasonal variations of radon concentrations in Kowary differ from those usually registered in temperate climate. Based on our analyses, the increase of radon concentration in winter and spring was caused by inversion occurring in that area during these seasons. The observed seasonal variations of radon concentrations in the spoil tip were consistent with those characteristic for temperate climate (the highest radon concentration registered in spring and summer and the lowest in winter and autumn). The spoil tip is located above 900m a.s.l. and is not cover by grass or trees. These circumstances promoted radon exhalation. The air movement above the spoil tip area is intensive, even in winter time. The average atmospheric radon concentration in the spoil tip was 318Bqm(-3). The performed research did not reveal occurrence of radon density currents and flow of radon from the spoil tip to lower lying areas in Kowary. We noticed interdependence of atmospheric radon concentration measured at the height of 1.5 above the ground and uranium content in soil and no correlation between thorium content and radon concentration. The lung cancer in residents of Kowary which is more common than in Poland can be associated with increased concentrations of radon. The average radon concentration in the atmosphere in Kowary was 79Bq m(-3).

  19. Dosimetric challenges for residential radon epidemiology.

    PubMed

    Steck, Daniel J; Field, R William

    2006-04-01

    Radon concentration alone may not be an adequate surrogate to measure for lung cancer risk in all residential radon epidemiologic lung cancer studies. The dose delivered to the lungs per unit radon exposure can vary significantly with exposure conditions. These dose-effectiveness variations can be comparable to spatial and temporal factor variations in many situations. New technologies that use surface-deposited and implanted radon progeny activities make more accurate dose estimates available for future epidemiologic studies.

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

    NASA Astrophysics Data System (ADS)

    Przylibski, Tadeusz

    2010-05-01

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

  1. Radon Risk Perception and Testing: Sociodemographic Correlates.

    ERIC Educational Resources Information Center

    Halpern, Michael T.; Warner, Kenneth E.

    1994-01-01

    Using information from the 1990 National Health Interview Survey, examined beliefs regarding radon and radon-testing activities among different sociodemographic groups. Results suggest relatively superficial knowledge regarding radon, and little testing, within the survey population. Significantly less knowledge was observed among female and…

  2. 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...

  3. 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…

  4. 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...

  5. Is Your School Safe from Radon?

    ERIC Educational Resources Information Center

    Martin, Paul

    1990-01-01

    Radon is a natural, chemically inert, radioactive gas that can seep to the surface from underground rocks. As many as 20,000 lung cancer deaths in the U.S. each year may be radon-caused. Screening a school for radon is not difficult and may be done on weekends. It's safer for students and staff to test and be sure. (MLH)

  6. Is Your School Safe from Radon?

    ERIC Educational Resources Information Center

    Martin, Paul

    1990-01-01

    Radon is a natural, chemically inert, radioactive gas that can seep to the surface from underground rocks. As many as 20,000 lung cancer deaths in the U.S. each year may be radon-caused. Screening a school for radon is not difficult and may be done on weekends. It's safer for students and staff to test and be sure. (MLH)

  7. Radon Risk Perception and Testing: Sociodemographic Correlates.

    ERIC Educational Resources Information Center

    Halpern, Michael T.; Warner, Kenneth E.

    1994-01-01

    Using information from the 1990 National Health Interview Survey, examined beliefs regarding radon and radon-testing activities among different sociodemographic groups. Results suggest relatively superficial knowledge regarding radon, and little testing, within the survey population. Significantly less knowledge was observed among female and…

  8. 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.

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

    SciTech Connect

    Evans, H.H.

    1991-12-01

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

  10. Concentration of 226Ra in rocks of the southern part of Lower Silesia (SW Poland).

    PubMed

    Przylibski, Tadeusz Andrzej

    2004-01-01

    The aim of the article is to present a preliminary description of rocks in the southern part of Lower Silesia and the Sudety Mountains in particular, with regard to 226Ra content. The research demonstrates that the average content of this isotope was 40.4 Bq/kg in the rocks of the southern part of Lower Silesia, and 41.7 Bq/kg in the rocks of the Sudetes. These values are slightly higher than the mean 226Ra content in the upper part of the Earth's crust, while the measured maximum content of this isotope (244 Bq/kg) is more than twice as high as the upper range of the values most frequently recorded in the upper part of the Earth's crust. The minimum values were lower than the detection limit, which was about 1 Bq/kg. These results reflect the mosaic-like geological structure of Lower Silesia, and particularly the Sudety Mountains, the occurrence of SiO2-rich igneous rocks and the products of their metamorphism, as well as numerous manifestations of uranium mineralisation or even deposital concentrations of this element. The rocks with the highest 226Ra contents include (in decreasing order): aplites, granites, gneisses and leucogranites, granite-gneisses, granodiorites and rhyolites, and, finally, mudstones. The lowest values of 226Ra content, on the other hand, were measured in sandstones, marls and conglomerates, and extremely low-in marbles and quartzites. The results show that background values of 226Ra content in the rocks of the southern part of Lower Silesia fall within a range from several to about 100 Bq/kg, which is the same as the range most frequently recorded in the upper part of the Earth's crust. Distribution of these values has log-normal character. The research demonstrates that the southern part of Lower Silesia, and the Sudetes in particular, may be marked by an increased radon potential. Particularly liable areas are: the Karkonosze granite massif, especially in its border zones, the Ladek-Snieznik and the Izera massifs, especially in their

  11. A Radon Progeny Deposition Model

    SciTech Connect

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-04-27

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

  12. A radon progeny deposition model

    SciTech Connect

    Rielage, Keith; Elliott, Steven R; Hime, Andrew; Guiseppe, Vincente E; Westerdale, S.

    2010-12-01

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

  13. 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).

  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. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. 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.

  17. 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.

  18. Modeling radon transport in dry, cracked soil

    SciTech Connect

    Holford, D.J. ); Schery, S.D.; Wilson, J.L.; Phillips, F.M. )

    1993-01-10

    A two-dimensional finite element code was used to investigate the effect of changes in surface air pressure on radon flux from soil with parallel, partially penetrating cracks. A sensitivity analysis investigates the effects of various crack dimensions, soil characteristics, and surface air pressure on radon flux from the soil surface to the atmosphere. Simulation results indicate that radon flux is most sensitive to soil properties; the diffusion coefficient is most important, followed by permeability and porosity. Radon flux is also sensitive to changes in barometric pressure, which cause variations in radon flux above and below the average diffusive flux. Sinusoidal variations in barometric pressure cause a net increase in the average radon flux from the soil, because increases in flux during periods of decreasing pressure are greater than the decreases in flux during periods of decreasing pressure of equal magnitude. Cracks were found to significantly increase radon flux from soils of low permeability. 33 refs. 19 figs., 1 tab.

  19. 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.

  20. Automatically processed alpha-track radon monitor

    DOEpatents

    Langner, G.H. Jr.

    1993-01-12

    An automatically processed alpha-track radon monitor is provided which includes a housing having an aperture allowing radon entry, and a filter that excludes the entry of radon daughters into the housing. A flexible track registration material is located within the housing that records alpha-particle emissions from the decay of radon and radon daughters inside the housing. The flexible track registration material is capable of being spliced such that the registration material from a plurality of monitors can be spliced into a single strip to facilitate automatic processing of the registration material from the plurality of monitors. A process for the automatic counting of radon registered by a radon monitor is also provided.

  1. Automatically processed alpha-track radon monitor

    DOEpatents

    Langner, Jr., G. Harold

    1993-01-01

    An automatically processed alpha-track radon monitor is provided which includes a housing having an aperture allowing radon entry, and a filter that excludes the entry of radon daughters into the housing. A flexible track registration material is located within the housing that records alpha-particle emissions from the decay of radon and radon daughters inside the housing. The flexible track registration material is capable of being spliced such that the registration material from a plurality of monitors can be spliced into a single strip to facilitate automatic processing of the registration material from the plurality of monitors. A process for the automatic counting of radon registered by a radon monitor is also provided.

  2. Transport of radon from soil into residences

    SciTech Connect

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

    1984-02-01

    To develop effective monitoring and control programs for indoor radon it is important to understand the causes of the broad range of concentrations that has been observed. Measurements of indoor radon concentration and air-exchange rate in dwellings in several countries indicate that this variability arises largely from differences among structures in the rate of radon entry. Recent evidence further suggests that the major source of indoor radon in many circumstances is the soil adjacent to the building foundation and that pressure-driven flow, rather than molecular diffusion, is the dominant transport process by which radon enters the buildings. Key factors affecting radon transport from soil are radon production in soil, flow-inducing mechanisms, soil permeability, and building substructure type. 24 references, 1 figure.

  3. Automatically processed alpha-track radon monitor

    SciTech Connect

    Langner, G.H. Jr.

    1991-05-02

    An automatically processed alpha-track radon monitor is provided which includes a housing having an aperture allowing radon entry, and a filter that excludes the entry of radon daughters into the housing. A flexible track registration material is located within the housing that records alpha-particle emissions from the decay of radon and radon daughters inside the housing. The flexible track registration material is capable of being spliced such that the registration material from a plurality of monitors can be spliced into a single strip to facilitate automatic processing of the registration material from the plurality of monitors. A process for the automatic counting of radon registered by a radon monitor is also provided.

  4. 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

  5. 76 FR 72006 - Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-21

    ... COMMISSION Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon... Recovery Facility Surveys of Radon and Radon Progeny in Air and Demonstrations of Compliance with 10 CFR 20... that existing guidance does not sufficiently detail how the NRC staff reviews surveys of radon and...

  6. 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. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. NEW APPROACHES: Teaching about radon

    NASA Astrophysics Data System (ADS)

    Sang, David; Sutcliffe, Jill

    1997-03-01

    Radon is a major natural hazard and people should know about it. But exactly what needs to be known, how should it be taught and what resources are available to teach it? The answers suggest that a good deal of work needs to be done.

  8. 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. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Indoor radon correlated with soil and subsoil radon potential—a case study

    NASA Astrophysics Data System (ADS)

    Keller, G.; Schneiders, H.; Schütz, M.; Siehl, A.; Stamm, R.

    1992-03-01

    High indoor radon concentrations in a uranium-radium low-level area in the Eifel region, Germany, near the village of Döttingen are caused by ascending radon migration following the convection of groundwater and soil gas along pathways (fractures and faults) in the bedrock sediments of Lower Devonian age. Positive radon anomalies in the soil gas are found to coincide with the locations of houses showing the highest concentrations. These houses are older buildings without concrete foundation slabs. Normally radon concentrations in soil gas are highly correlated with the values of emanated radon calculated on the basis of radium content in the surrounding soils and rocks (diffusive radon potential). However, close to zones of tectonic fractures and faults around the maar-type volcano of Döttingen abnormally high radon concentrations, which were transported by circulating groundwater and postvolcanic exhalation of CO2 (convective radon potential) were detected.

  10. Radon/radon daughter environmental chamber located in the northwest end of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Radon/radon daughter environmental chamber located in the northwest end of building. VIEW LOOKING WEST - Department of Energy, Grand Junction Office, Building No. 32, 2597 B3/4 Road, Grand Junction, Mesa County, CO

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

    MedlinePlus

    Jump to main content We’ve made some changes to EPA.gov . If the information you are ... The Guide to Protecting Yourself and Your Family from Radon Contains basic information about Radon in the home, how to ...

  12. General Services Administration Childcare Radon Results in the Federal Radon Action Plan

    EPA Pesticide Factsheets

    GSA made a commitment to support the FRAP’s radon risk goal by sampling for radon in its childcare centers. Over the past two years, the sampling has been performed by independent consultants using recommended standard methods and protocols.

  13. 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.

  14. Alpha Recoil Flux of Radon in Groundwater and its Experimental Measurement

    NASA Astrophysics Data System (ADS)

    Mehta, N.; Harvey, C. F.; Kocar, B. D.

    2016-12-01

    Groundwater Radon (Rn222) activity is primarily controlled by alpha recoil process (radioactive decay), however, evaluating the rate and extent of this process, and its impact on porewater radioactivity, remains uncertain. Numerous factors contribute to this uncertainty, including the spatial distribution of parent radionuclides (e.g. U238, Th232 , Ra226 and Ra228) within native materials, differences in nuclide recoil length in host matrix and the physical structure of the rock strata (pore size distribution and porosity). Here, we experimentally measure Radon activities within porewater contributed through alpha recoil, and analyze its variations as a function of pore structure and parent nuclide distribution within host matrices, including Marcellus shale rock and Serrie-Copper Pegmatite. The shale cores originate from the Marcellus formation in Mckean, Pennsylvania collected at depths ranging from 1000-7000 feet, and the U-Th-rich Pegmatite is obtained from South Platte District, Colorado. Columns are packed with granulated rock of varying surface area (30,000-60,000 cm2/g) and subjected to low salinity sodium chloride solution in a close loop configuration. The activity of Radon (Rn222) and radium (Ra226) in the saline fluid is measured over time to determine recoil supply rates. Mineralogical and trace element data for rock specimens are characterized using XRD and XRF, and detailed geochemical profiles are constructed through total dissolution and analysis using ICP-MS and ICP-OES. Naturally occurring Radium nuclides and its daughters are quantified using a low-energy Germanium detector. The parent nuclide (U238 and Th232) distribution in the host rock is studied using X-Ray Absorption Spectroscopy (XAS). Our study elucidates the contribution of alpha recoil on the appearance and distribution of Radon (Rn222) within porewater of representative rock matrices. Further, we illustrate the effects of chemical and physical heterogeneity on the rate of this process

  15. Modeling of indoor radon concentration from radon exhalation rates of building materials and validation through measurements.

    PubMed

    Kumar, Amit; Chauhan, R P; Joshi, Manish; Sahoo, B K

    2014-01-01

    Building materials are the second major source of indoor radon after soil. The contribution of building materials towards indoor radon depends upon the radium content and exhalation rates and can be used as a primary index for radon levels in the dwellings. The radon flux data from the building materials was used for calculation of the indoor radon concentrations and doses by many researchers using one and two dimensional model suggested by various researchers. In addition to radium content, the radon wall flux from a surface strongly depends upon the radon diffusion length (L) and thickness of the wall (2d). In the present work the indoor radon concentrations from the measured radon exhalation rate of building materials calculated using different models available in literature and validation of models was made through measurement. The variation in the predicted radon flux from different models was compared with d/L value for wall and roofs of different dwellings. The results showed that the radon concentrations predicted by models agree with experimental value. The applicability of different model with d/L ratio was discussed. The work aims to select a more appropriate and general model among available models in literature for the prediction of indoor radon. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Radon and its daughters in vivo

    SciTech Connect

    Rundo, J.

    1983-01-01

    Some aspects of the behavior of radon and its short-lived daughters in vivo are described and a relationship between the radon exhalation rate and time after a meal is demonstrated. A major but short-lived postprandial increase in the exhalation rate of radon produced from skeletally-deposited radium was observed and a similar effect in exhalation rate of environmental radon by persons containing no radium was noted. Persons living in houses with elevated concentrations of radon may contain sufficient activity for its detection by external gamma-ray counting. Some of the activity observed is due to inhaled daughter-products in the chest, and some to daughter-products associated with and produced by the decay of radon throughout the body. 3 references, 8 figures. (MF)

  17. National radon contractor proficiency program. Proficiency report

    SciTech Connect

    Not Available

    1991-02-01

    The report lists those individual contractors who have met the requirements of the Radon Contractor Proficiency (PCP) Program as of December 15, 1990. These requirements are designed to provide minimum proficiency criteria for individuals who design and supervise the installation of radon mitigation systems in buildings. The RCP Program measures the proficiency of an individual contractor, not their company. The report provides the program requirements, RCP mitigation guidelines, State Radon contacts, and information on how to use the RCP tables.

  18. 21 CFR 226.110 - Distribution records.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Distribution records. 226.110 Section 226.110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS... Distribution records. Complete records shall be maintained for each shipment of Type A medicated article(s)...

  19. 13 CFR 134.226 - The decision.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false The decision. 134.226 Section 134... BEFORE THE OFFICE OF HEARINGS AND APPEALS Rules of Practice § 134.226 The decision. (a) Contents. (1) Following close of record, the Judge will issue a decision containing findings of fact and conclusions of...

  20. 13 CFR 134.226 - The decision.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false The decision. 134.226 Section 134... BEFORE THE OFFICE OF HEARINGS AND APPEALS Rules of Practice § 134.226 The decision. (a) Contents. (1) Following close of record, the Judge will issue a decision containing findings of fact and conclusions of...

  1. 13 CFR 134.226 - The decision.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false The decision. 134.226 Section 134... BEFORE THE OFFICE OF HEARINGS AND APPEALS Rules of Practice § 134.226 The decision. (a) Contents. (1) Following close of record, the Judge will issue a decision containing findings of fact and conclusions of...

  2. 21 CFR 226.115 - Complaint files.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Complaint files. 226.115 Section 226.115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL... files. Records shall be maintained for a period of 2 years of all written or verbal...

  3. 1 CFR 22.6 - Code designation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Code designation. 22.6 Section 22.6 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER PREPARATION, TRANSMITTAL, AND PROCESSING OF... placing the appropriate CFR citation immediately below the name of the issuing agency. For example: 1 CFR...

  4. 32 CFR 226.1 - Purpose.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 2 2012-07-01 2012-07-01 false Purpose. 226.1 Section 226.1 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR... Defense policy for the Department of Defense Shelter for the Homeless Program....

  5. 32 CFR 226.1 - Purpose.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 2 2013-07-01 2013-07-01 false Purpose. 226.1 Section 226.1 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR..., assigning responsibilities, and prescribing procedures for providing shelter for the homeless on...

  6. 32 CFR 226.1 - Purpose.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 2 2014-07-01 2014-07-01 false Purpose. 226.1 Section 226.1 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR..., assigning responsibilities, and prescribing procedures for providing shelter for the homeless on...

  7. 32 CFR 226.1 - Purpose.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 2 2011-07-01 2011-07-01 false Purpose. 226.1 Section 226.1 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR... Defense policy for the Department of Defense Shelter for the Homeless Program....

  8. 32 CFR 226.1 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Purpose. 226.1 Section 226.1 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS SHELTER FOR... Defense policy for the Department of Defense Shelter for the Homeless Program....

  9. 50 CFR 665.226 - Notifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... coral reef ecosystem MUS unit species harvested under a special permit, and report the port and the... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Notifications. 665.226 Section 665.226 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC...

  10. 7 CFR 226.15 - Institution provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE CHILD NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM Operational Provisions § 226.15... meals in accordance with § 226.23(e)(1). For child care centers, such documentation of enrollment must be updated annually, signed by a parent or legal guardian, and include information on each...

  11. 31 CFR 226.7 - Effective date.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Effective date. 226.7 Section 226.7 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY FINANCIAL MANAGEMENT SERVICE RECOGNITION OF INSURANCE COVERING TREASURY TAX...

  12. 29 CFR 553.226 - Training time.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Training time. 553.226 Section 553.226 Labor Regulations... time. (a) The general rules for determining the compensability of training time under the FLSA are set forth in §§ 785.27 through 785.32 of this title. (b) While time spent in attending training required by...

  13. 29 CFR 553.226 - Training time.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Training time. 553.226 Section 553.226 Labor Regulations... time. (a) The general rules for determining the compensability of training time under the FLSA are set forth in §§ 785.27 through 785.32 of this title. (b) While time spent in attending training required by...

  14. 48 CFR 226.7102 - Policy.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Policy. 226.7102 Section 226.7102 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF....7102 Policy. Businesses located in the vicinity of a military installation that is being closed or...

  15. 48 CFR 226.7101 - Definition.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Definition. 226.7101 Section 226.7101 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT... military installation to be closed or realigned is located and all adjacent counties, unless otherwise...

  16. 48 CFR 226.7104 - Other considerations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Other considerations. 226.7104 Section 226.7104 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM... activities at a military installation affected by a closure or realignment under a base closure law...

  17. 48 CFR 52.226 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false 52.226 Section 52.226 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION (CONTINUED) CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses...

  18. 42 CFR 93.226 - Retaliation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Retaliation. 93.226 Section 93.226 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES ON RESEARCH...

  19. 42 CFR 93.226 - Retaliation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Retaliation. 93.226 Section 93.226 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES ON RESEARCH...

  20. 42 CFR 93.226 - Retaliation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Retaliation. 93.226 Section 93.226 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES ON RESEARCH...

  1. 42 CFR 93.226 - Retaliation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Retaliation. 93.226 Section 93.226 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES ON RESEARCH...

  2. 42 CFR 93.226 - Retaliation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Retaliation. 93.226 Section 93.226 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES HEALTH ASSESSMENTS AND HEALTH EFFECTS STUDIES OF HAZARDOUS SUBSTANCES RELEASES AND FACILITIES PUBLIC HEALTH SERVICE POLICIES ON RESEARCH...

  3. 22 CFR 226.91 - Marking.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... marking must be installed. (c) Subject to § 226.91 (a), (h), and (j), technical assistance, studies... study/report/audio/visual/other information/media product (specify) is made possible by the generous... Strategy, defined in § 226.2. The proposed Branding Strategy will not be evaluated competitively. The...

  4. 21 CFR 556.226 - Enrofloxacin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Enrofloxacin. 556.226 Section 556.226 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for...

  5. 12 CFR 226.10 - Payments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Payments. 226.10 Section 226.10 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN...) Specifying one particular address for receiving payments, such as a post office box. (3) In-person...

  6. Modeling radium and radon transport through soil and vegetation

    USGS Publications Warehouse

    Kozak, J.A.; Reeves, H.W.; Lewis, B.A.

    2003-01-01

    A one-dimensional flow and transport model was developed to describe the movement of two fluid phases, gas and water, within a porous medium and the transport of 226Ra and 222Rn within and between these two phases. Included in this model is the vegetative uptake of water and aqueous 226Ra and 222Rn that can be extracted from the soil via the transpiration stream. The mathematical model is formulated through a set of phase balance equations and a set of species balance equations. Mass exchange, sink terms and the dependence of physical properties upon phase composition couple the two sets of equations. Numerical solution of each set, with iteration between the sets, is carried out leading to a set-iterative compositional model. The Petrov-Galerkin finite element approach is used to allow for upstream weighting if required for a given simulation. Mass lumping improves solution convergence and stability behavior. The resulting numerical model was applied to four problems and was found to produce accurate, mass conservative solutions when compared to published experimental and numerical results and theoretical column experiments. Preliminary results suggest that the model can be used as an investigative tool to determine the feasibility of phytoremediating radium and radon-contaminated soil. ?? 2003 Elsevier Science B.V. All rights reserved.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. The Japanese Radon and Thoron Reference Chambers

    SciTech Connect

    Tokonami, Shinji; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Takahashi, Hiroyuki; Miyahara, Nobuyuki

    2008-08-07

    Passive detectors used for large-scale and long-term surveys are generally calibrated in a well-controlled environment such as a radon chamber. It has been also pointed out that some of them are sensitive to thoron. Thus it is necessary to check the thoron contribution to the detector response with the proposed or similar test before practical use. The NIRS accommodates radon/aerosol and thoron chambers for quality assurance and quality control of radon measurements. Thus both chambers work so well that they can supply us with the calibration technique and consequently, a good level of knowledge of the radon and thoron issue.

  12. Radon emanation on the San Andreas Fault

    USGS Publications Warehouse

    King, C. Y.

    1978-01-01

    Radon is a radioactive gas with a half-life of 3.8 days. (Half-life is the time required for the substance to lose half of its radioactivity by decay.) It is itself produced by the decay of uranium. Radon is constantly emanated from the Earth into the atmosphere. Many cases are known where anomalously large amounts of radon have been given off along active faults. THe radon emanation has shown variations with time that are related to changing atmospheric conidtions and possibly to nearby seismic activity. 

  13. Low-Cost Radon Reduction Pilot Study

    SciTech Connect

    Rose, William B.; Francisco, Paul W.; Merrin, Zachary

    2015-09-01

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

  14. Radon and thoron emanation measurements and the effect of ground water

    SciTech Connect

    Carriveau, G.W.; Harbottle, G.

    1980-01-01

    In the past, corrections for annual dose rate calculations have used a qualitative approach to the effect of ground water saturation and radon and thoron loss. An example is presented of how this correction can now be precisely determined using natural gamma-ray activities to determine the amount of emanation from ceramic sherds and soil, both in a dry state and saturated with ground water. The experimental data also provide information concerning disequilibria in /sup 234/Th and /sup 226/Ra regions of the decay series. Additionally, approximate values of uranium and thorium concentrations (sufficiently accurate for authenticity work) are provided.

  15. Radium-226 accumulation in Florida freshwater mussels

    USGS Publications Warehouse

    Brenner, M.; Smoak, J.M.; Leeper, D.A.; Streubert, M.; Baker, S.M.

    2007-01-01

    Selected lakes in Hillsborough County, Florida have been hydrologically augmented with groundwater to offset stage declines caused by excessive pumping of the Floridan Aquifer. Augmentation water can be relatively rich in 226Ra (>5 decays per minute [dpm] L-1). We measured 226Ra activities in shells and soft tissues of adult bivalve molluscs (Elliptio cf. buckleyi) from groundwater-augmented and nonaugmented lakes to assess bioaccumulation of 226Ra by mussels. Mussels from augmented lakes displayed higher 226Ra in both shells and tissues than did mussels from nonaugmented lakes. Within a sample, 226Ra activity in Elliptio tissues was higher than the value measured in shells. Highest activities were found in a composite mussel sample (n = 6) from an augmented lake; soft tissue activity was 619 ?? 33 dpm g-1 dry weight and shell activity was 147 ?? 7 dpm g-1 g dry weight. Large mussels displayed greater activities in soft tissues and shells than did small mussels. We transplanted animals from a nonaugmented lake into a groundwater-augmented water body. 226Ra activity in dry tissue rose from 32 ?? 1 to 196 ?? 2 dpm g-1 within 2 months. When 226Ra-rich mussels (232 ?? 2 dpm g-1) from the augmented lake were transferred to the nonaugmented lake, they showed no significant 226Ra loss over the 69-d experiment. Large Elliptio mussels concentrated 226Ra in their soft tissues to levels about 1,000 to 25,000 times concentrations in lake water. Pumping of groundwater in Florida for residential, agricultural, and industrial use contributes dissolved 226Ra to some surface water bodies, where it can be bioaccumulated by bivalve molluscs. ?? 2007, by the American Society of Limnology and Oceanography, Inc.

  16. 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.

  17. Radium-226-contaminated drinking water: Hypothesis on an exposure pathway in a population with elevated childhood leukemia

    SciTech Connect

    Hoffmann, W.; Kranefeld, A.; Schmitz-Feuerhake, I.

    1993-10-01

    A recent epidemiological survey on childhood malignant disease in the region of Ellweiler, Rheinland-Pfalz, Germany, revealed a significantly increased incidence of childhood leukemia, but observed incidences of lymphoma and solid tumors were normal. Established risk factors such as individual exposure to chemicals as well as hereditary genetic disorders were ruled out in interviews with the patients or their families. The general population in the region, however, is subjected to considerable doses of ionizing radiation due to high levels of external {gamma} radiation and high activities of indoor radon. Radiation-specific chromosome aberrations were found in one of two healthy siblings and one father of leukemia patients as well as in any of three probands living in houses with high indoor radon activities. Radon and natural {gamma} radiation, however, cannot explain the geographical pattern of the cases. Four out of seven cases were observed in two particular villages near a uranium processing plant. The drinking water of these villages partly came from a small river that was contaminated with radium-226 washed out from the dumps of the uranium plant. Only sparse measurements of {sup 226}Ra are available, but derived red bone marrow doses for children in the two villages obtained from a simple radio-ecological model show the significance of the drinking water pathway. Prenatal {sup 226}Ra exposure of fetuses due to placental transfer and accumulation may have led to significant doses and may explain the excess cases of childhood leukemia in the region even in quantitative terms. 11 refs., 6 tabs.

  18. Radon Emanation from Zircon as a Function of Grain Size, Temperature and Fission Track Density

    NASA Astrophysics Data System (ADS)

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

    2012-12-01

    Radon emanation from rocks and minerals is ubiquitous. Quantification of radon emanation rates from zircon is critical to assess the reliability of U-Pb ages of zircon bearing rocks. The 238U decay chain includes 222Rn, a noble gas, which can readily escape the crystal structure if sufficient escape pathways in lattice structure exist, ultimately leading to a deficiency of 206Pb in the parent crystal. Few studies have directly investigated the link between track density and 222Rn emanation rates, and none have done this for zircon. In order to evaluate the factors affecting radon emanation from the mineral zircon under different conditions, a series of experiments were performed on a large, crushed Mud Tank zircon crystal. Five different grain sizes (500 μm, 250-500 μm, 125-250 μm, 63 - 125 μm, and < 63 μm) were separated and sealed in closed glass jars and radon emanation rates were measured at 25 C. These aliquots are then subjected to a range of temperatures (100 C, 200 C, 400 C, and 600 C) for six hours and the radon emanation rates are measured after each heating step. Fission track densities are measured after the same annealing temperature steps allowing quantification of 222Rn emanation rate as a function of fission track density. The concentration of 210Pb, 234Th, 212Pb, 226Ra and 228Ra in these fractions are also measured using gamma spectroscopy. The results of these experiments will have implications for U-Pb dating (i.e., explanation of discordant ages), and noble gas escape systematics in zircon (i.e., volume diffusion or fast pathway escape). The possibility also exists for using 222Rn, or other noble gasses, as a measure of defect density within crystals.

  19. Using soil gas radon and geology to estimate regional radon potential

    USGS Publications Warehouse

    Reimer, G.M.

    1992-01-01

    Two important parameters have been identified in order to estimate the radon potential of a region. They are the soil gas radon concentration and the geological rock type from which soils are derived. A simple soil gas collection and analytical technique has been developed to provide information on soil gas radon concentrations. The application of these techniques has demonstrated a clear relationship between the estimate of the radon potential and indoor radon measurements. This information is particularly important when evaluating the radon potential of areas that will be subject to population expansion in the future. Other factors, such as gamma radiation measurements and soil permeability can be included to improve the estimate of radon potential, but geology and soil gas measurements are the most important factors. Although this approach is useful for regional estimates, it can also be used for site-specific evaluations.

  20. 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

  1. Radium-bearing pipe scale deposits: implications for national waterborne radon sampling methods.

    PubMed Central

    Field, R W; Fisher, E L; Valentine, R L; Kross, B C

    1995-01-01

    A point-of-use waterborne radon-222 (222Rn) survey of a small Iowa town was performed to determine the cause of unnaturally high waterborne 222Rn concentrations in the municipality. The source of the elevated 222Rn concentrations was a newly discovered reservoir of waterborne 222Rn originating from distribution-system radium-226 (226Ra) adsorbed internal pipe scale deposits. Because the proposed national drinking water regulations for 222Rn require sampling at the origin of the distribution system rather than at the point of use, the proposed scheme for collection of water samples may not represent actual consumer waterborne 222Rn exposure in all cases. Images FIGURE 1 PMID:7702126

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

  3. Assessment and management of residential radon health risks: a report from the health Canada radon workshop.

    PubMed

    Tracy, Bliss L; Krewski, Daniel; Chen, Jing; Zielinski, Jan M; Brand, Kevin P; Meyerhof, Dorothy

    2006-04-01

    Epidemiologic studies of uranium miners and other underground miners have consistently shown miners exposed to high levels of radon to be at increased risk of lung cancer. More recently, concern has arisen about lung cancer risks among people exposed to lower levels of radon in homes. The current Canadian guideline for residential radon exposure was set in 1988 at 800 Bq/m(3). Because of the accumulation of a considerable body of new scientific evidence on radon lung cancer risks since that time, Health Canada sponsored a workshop to review the current state-of-the-science on radon health risks. The specific objectives of the workshop were (1) to collect and assess scientific information relevant to setting national radon policy in Canada, and (2) to gather information on social, political, and operational considerations in setting national policy. The workshop, held on 3-4 March 2004, was attended by 38 invited scientists, regulators, and other stakeholders from Canada and the United States. The presentations on the first day dealt primarily with scientific issues. The combined analysis of North American residential radon and lung cancer studies was reviewed. The analysis confirmed a small but detectable increase in lung cancer risk at residential exposure levels. Current estimates suggest that radon in homes is responsible for approximately 10% of all lung cancer deaths in Canada, making radon the second leading cause of lung cancer after tobacco smoking. This was followed by a perspective from an UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) working group on radon. There were two presentations on occupational exposures to radon and two presentations considered the possibility of radon as a causative factor for cardiovascular disease and for cancer in other organs besides the lung. The possible contribution of environmental tobacco smoke to lung cancers in nonsmokers was also considered. Areas for future research were identified

  4. Hidden Hazards of Radon: Scanning the Country for Problem Locations.

    ERIC Educational Resources Information Center

    Gundersen, Linda C. S.

    1992-01-01

    Describes the geology of the radon problem in the United States and suggests how homeowners can cope with the radio active gas. Vignettes illustrate how and where radon is produced beneath the earth's surface, testing sites and procedures for radon in houses, and locations for potential radon problems across the United States. (MCO)

  5. SITE-SPECIFIC MEASUREMENTS OF RESIDENTIAL RADON PROTECTION CATEGORY

    EPA Science Inventory

    The report describes a series of benchmark measurements of soil radon potential at seven Florida sites and compares the measurements with regional estimates of radon potential from the Florida radon protection map. The measurements and map were developed under the Florida Radon R...

  6. Hidden Hazards of Radon: Scanning the Country for Problem Locations.

    ERIC Educational Resources Information Center

    Gundersen, Linda C. S.

    1992-01-01

    Describes the geology of the radon problem in the United States and suggests how homeowners can cope with the radio active gas. Vignettes illustrate how and where radon is produced beneath the earth's surface, testing sites and procedures for radon in houses, and locations for potential radon problems across the United States. (MCO)

  7. Find a Radon Test Kit or Measurement and Mitigation Professional

    EPA Pesticide Factsheets

    Find a qualified radon service professional to fix or mitigate your home. If you have questions about a radon, you should contact your state radon contact and/or contact one or both of the two privately-run National Radon Proficiency Programs

  8. SITE-SPECIFIC MEASUREMENTS OF RESIDENTIAL RADON PROTECTION CATEGORY

    EPA Science Inventory

    The report describes a series of benchmark measurements of soil radon potential at seven Florida sites and compares the measurements with regional estimates of radon potential from the Florida radon protection map. The measurements and map were developed under the Florida Radon R...

  9. Radon Measurement in Schools. Revised Edition.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    The Environmental Protection Agency (EPA) and other major national and international scientific organizations have concluded that radon is a human carcinogen and a serious environmental health problem. The EPA has conducted extensive research on the presence and measurement of radon in schools. This report provides school administrators and…

  10. Removal of Radon from Household Water.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Research and Development.

    By far, the greatest risk to health from radon occurs when the gas enters the house from underlying soil and is inhaled. The U.S. Environmental Protection Agency (EPA) is studying ways to reduce radon in houses, including methods to remove the gas from water to prevent its release in houses when the water is used. While this research has not…

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

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

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

  12. TEST CELL STUDIES OF RADON ENTRY

    EPA Science Inventory

    The report gives results of a study to contrast the effectiveness of slab-in-stem wall (SSW) with floating slab (FS) construction practices, to measure radon transport and entry for model testing, to develop protocols relevant to depressurized radon measurements, and to determine...

  13. TEST CELL STUDIES OF RADON ENTRY

    EPA Science Inventory

    The report gives results of a study to contrast the effectiveness of slab-in-stem wall (SSW) with floating slab (FS) construction practices, to measure radon transport and entry for model testing, to develop protocols relevant to depressurized radon measurements, and to determine...

  14. Characterization of radon levels in indoor air

    SciTech Connect

    George, A.C.

    1982-01-01

    The purpose is to describe the different types of monitoring and sampling techniques that can determine the radiation burden of the general public from radon and its decay products. This is accomplished by measuring the range and distribution of radon and radon decay products through broad surveys using simple and convenient integrating monitoring instruments. For in-depth studies of the behavior of radon decay products and calculation of the radiation dose to the lung, fewer and more intensive and complex measurements of the particle size distribution and respiratory deposition of the radon decay products are required. For diagnostic purposes, the paper describes measurement techniques of the sources and exhalation rate of radon and the air exchange inside buildings. Measurement results form several studies conducted in ordinary buildings in different geographical areas of the United States, using the described monitoring techniques, indicate that the occupants of these buildings are exposed to radon and radon decay product concentrations, varying by as much as a factor of 20.

  15. Decadal radon cycles in a hot spring.

    PubMed

    Yan, Rui; Woith, Heiko; Wang, Rongjiang; Wang, Guangcai

    2017-09-21

    A high-fidelity record covering nearly 40 years of water-dissolved radon from the hot spring site of BangLazhang (BLZ), Southwestern China is presented to study multi-year periodicities of radon. Ancillary observational data, i.e., water temperature, spring discharge rate, barometric pressure, combined with regional rainfall, galactic cosmic rays (GCR flux is modulated by solar wind and thus a proxy for solar activity) and regional seismicity from the same period are considered to identify potentially influencing factors controlling the changes in radon. Variations in radon concentration and ancillary observational data are studied using continuous Wavelet Power Spectrum (WPS), Wavelet Coherence (WTC), and Partial Wavelet Coherence (PWC). The results show that the long-period radon concentration is characterized by a quasi-decadal (8-11 years) cycle, matching well with the concurrent periodicity in water temperature, spring discharge rates and GCR. PWCs of radon, discharge rate and water temperature suggest that water temperature variations explain most of the coherent variability of radon and the discharge rate. We tentatively conclude that radon variations are mainly explained by variations in water temperature and spring discharge, which are modified and modulated by earthquakes and quasi-decadal variations of an unidentified process. The influence of solar activity on the decadal periodicity is discussed.

  16. Radon Measurements in Schools: An Interim Report.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Radiation Programs.

    Radon-222 is a colorless, odorless, tasteless, radioactive gas that occurs naturally in soil, rocks, underground water, and air. The United States Environmental Protection Agency (EPA) and other scientific organizations have identified an increased risk of lung cancer associated with exposure to elevated levels of radon in homes. Schools in many…

  17. Radon Risk Communication Strategies: A Regional Story.

    PubMed

    Cheng, Winnie

    2016-01-01

    Risk communication on the health effects of radon encounters many challenges and requires a variety of risk communication strategies and approaches. The concern over radon exposure and its health effects may vary according to people's level of knowledge and receptivity. Homeowners in radon-prone areas are usually more informed and have greater concern over those not living in radon-prone areas. The latter group is often found to be resistant to testing. In British Columbia as well as many other parts of the country, some homes have been lying outside of the radon-prone areas have radon levels above the Canadian guideline, which is the reason Health Canada recommends that all homes should be tested. Over the last five years, the Environment Health Program (EHP) of Health Canada in the British Columbia region has been using a variety of different approaches in their radon risk communications through social media, workshops, webinars, public forums, poster contests, radon distribution maps, public inquiries, tradeshows and conference events, and partnership with different jurisdictions and nongovernmental organizations. The valuable lessons learned from these approaches are discussed in this special report.

  18. 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.

  19. (The determination of sup 222 Rn flux from soils based on sup 210 Pb and sup 226 Ra disequilibrium)

    SciTech Connect

    Turekian, K.K.

    1991-01-01

    The emanating fraction of radon in soils from the southern part of the United States is about 40% greater than in those from the northern part. The mean {sup 226}Ra activity in the southern soils is also slightly higher and as a consequence the {sup 222}Rn flux derived from the top 50 cm. is greater in the southern samples. We tentatively attribute these observations to the greater degree of weathering associated with the pre-glacial age of the parent material of many of the southern soils. The weathering has concentrated {sup 226}Ra near grain surfaces and results in an increased emanating power for {sup 222}Rn. The estimated correction in {sup 210}Pb analyses described above results in a small decrease in our estimate of the mean loss rate of {sup 222}Rn from the upper 50 cm of soils.

  20. 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%.

  1. An improved scintillation cell for radon measurements

    NASA Astrophysics Data System (ADS)

    Quindos-Poncela, L. S.; Fernandez, P. L.; Sainz, C.; Arteche, J.; Arozamena, J. G.; George, A. C.

    2003-10-01

    Scintillation cells like "Modified Lucas cells" are widely used for grab-sample measurements of radon in the environment including those developed in the laboratory for evaluation of radon diffusion coefficients of radon barriers, radon emanation powers in small samples of porous materials and radon concentrations in small chambers used for different research studies. In this paper we describe the main characteristics of an improved and practical scintillation cell developed in our laboratory. Experimental efficiency values obtained for different cell volumes ranged between 0.038 and 0.123 cpm/Bq/m 3. The effects of atmospheric pressure on the detection efficiency as a function of the diameter of the cell were also studied. In general, a decrease of 15% was observed when increasing the pressure from 827 to 1013 hPa.

  2. 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.

  3. Radon exposure and oropharyngeal cancer risk.

    PubMed

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

    2015-12-01

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

  4. 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??.

  5. Radon risk perception and testing: Sociodemographic correlates

    SciTech Connect

    Halpern, M.T.; Warner, K.E. . Technology Assessment and Policy Research Center)

    1994-03-01

    While numerous health education campaigns have been carried out to alert the public to radon's potential dangers and to encourage testing and mitigation, there has been little follow-up to determine which segments of the public are now most aware of the possible hazards of radon. Using information from the 1990 National Health Interview Survey (NHIS), the authors have examined beliefs regarding radon and radon-testing activities among different sociodemographic groups. They used logistic regression to determine the relationship between these beliefs and actions and age, gender, education, income, minority status, and smoking status. The results suggest relatively superficial knowledge regarding radon, and very little testing, within the survey population. In particular, significantly less knowledge was observed among female and minority respondents, while less testing behavior was seen among older respondents. Lower educational levels and lower family income were associated with both decreased knowledge and testing. Recommendations for future education campaigns are discussed.

  6. 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

  7. Air cleaning and radon decay product mitigation

    SciTech Connect

    Hopke, P.K. ); Li, C.S. . John B. Pierce Foundation Lab.); Ramamurthi, M. )

    1990-01-01

    We evaluated air cleaning as a means to mitigate risks arising from exposure to indoor radon progeny in several single-family houses in the northeastern United States, using a new, automated, semi-continuous activity-weighted size distribution measurement system. Measurements included radon concentration, condensation nuclei count, and activity-weighted size distribution of radon decay products. Measurements were made with and without the air cleaning system operating. The influence of particles generated by various sources common to normal indoor activities on radon progeny behavior was evaluated. Aerosols were generated by running water in a shower, burning candles, smoking cigarettes, vacuuming, opening doors, and cooking. Both a filtration unit and an electrostatic precipitator were evaluated. Using a room model, the changes in attachment rates, average attachment diameters, and deposition rates of the unattached'' fraction with and without the air cleaning systems were calculated. The air cleaner typically reduced the radon progeny concentrations by 50 to 60%.

  8. A complete low cost radon detection system.

    PubMed

    Bayrak, A; Barlas, E; Emirhan, E; Kutlu, Ç; Ozben, C S

    2013-08-01

    Monitoring the (222)Rn activity through the 1200 km long Northern Anatolian fault line, for the purpose of earthquake precursory, requires large number of cost effective radon detectors. We have designed, produced and successfully tested a low cost radon detection system (a radon monitor). In the detector circuit of this monitor, First Sensor PS100-7-CER-2 windowless PIN photodiode and a custom made transempedence/shaping amplifier were used. In order to collect the naturally ionized radon progeny to the surface of the PIN photodiode, a potential of 3500 V was applied between the conductive hemi-spherical shell and the PIN photodiode. In addition to the count rate of the radon progeny, absolute pressure, humidity and temperature were logged during the measurements. A GSM modem was integrated to the system for transferring the measurements from the remote locations to the data process center.

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

    PubMed

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

    2016-11-01

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

  10. 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.

  11. 7 CFR 226.22 - Procurement standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE CHILD NUTRITION PROGRAMS CHILD AND ADULT CARE FOOD PROGRAM Operational Provisions § 226.22... or transmission of intelligence; (5) The contract shall include notice of USDA requirements and...

  12. 12 CFR 226.31 - General rules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... LENDING (REGULATION Z) Special Rules for Certain Home Mortgage Transactions § 226.31 General rules. (a... creditor delivers the required disclosures, the inaccuracy is not a violation of Regulation Z (12 CFR part...

  13. Nuclear data sheets for A = 226

    SciTech Connect

    Akovali, Y. A.

    1996-02-01

    The available nuclear structure information for all nuclei with mass number A = 226 is presented. Various decay and reaction data are evaluated and compared. Adopted data, levels, spin, parity and configuration assignments are given. 134 refs.

  14. 21 CFR 226.10 - Personnel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES General Provisions § 226.10 Personnel... and the safety, identity, strength, quality, and purity that it purports to possess. ...

  15. 21 CFR 226.115 - Complaint files.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES Records and Reports § 226.115 Complaint... concerning the safety or efficacy of each Type A medicated article(s). Complaints shall be evaluated by...

  16. 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.

  17. Modeled atmospheric radon concentrations from uranium mines

    SciTech Connect

    Droppo, J.G.

    1985-04-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  19. 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.

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

    NASA Astrophysics Data System (ADS)

    Alhalemi, Ahmed; Jaafar, M. S.

    2010-07-01

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

  1. Evaluation of experiences in long-term radon and radon-daughter measurements

    SciTech Connect

    Young, J.A.; Jackson, P.O.; Thomas, V.W.

    1982-12-01

    Pacific Northwest Laboratory (PNL) is performing side-by-side measurements of radon and radon daughter concentrations using several instruments and techniques, and is comparing these measurements with side-by-side measurements made by other investigators at other locations. The standard deviation of the differences between the (natural) logarithms of the Terradex Track Etch radon concentrations and the logarithms of the Radon Progency Integrating Sampling Units (RPISU) radon daughter concentrations (S.D.-ln) measured in 50 buildings in Edgemont, South Dakota, was 0.37. Using this S.D.-ln, it can be calculated that if the Track Etch radon daughter concentration is 0.010 WL there should be only a 14% probability that the RPISU average would be greater than 0.015 WL, and only a 3% probability tht the RPISU average would be greater than 0.020 WL. If buildings had been cleared from remedial action when the Track Etch averages were less than 0.10 WL, then about 61% of the buildings would have been cleared from remedial action, and only a few percent of these buildings would have actually had average RPISU concentrations greater than 0.015 WL. The S.D.-ln between the Track Etch radon measurements and the RPISU radon daughter measurements made by ALARA at Grand Junction, the PERM radon measurements and the MOD-225 radon daughter measurements made by Mound Facility at Canonsburg and Middlesex, and the PERM and Track Etch radon measurements made by Mound Facility at Salt Lake City were similar to the S.D.-ln between the Track Etch radon measurements and the RPISU radon daughter measurements at Edgemont.

  2. Temporal variations of radon in soil related to earthquakes.

    PubMed

    Planinić, J; Radolić, V; Lazanin, Z

    2001-08-01

    A radon detector with LR-115 nuclear track film was constructed for radon concentration measurements in soil. Temporal radon variations, as well as the barometric pressure, precipitation and temperature were measured for two years. Negative correlation between radon concentration in soil and barometric pressure was found. For some of the recorded earthquakes that occurred during the observation period, soil radon anomalies may be noticed one month before the quakes.

  3. Development of solid radium-226 reference materials

    SciTech Connect

    Chessmore, R.B.; Engelder, P.R.; Sill, C.W.

    1983-11-01

    Radium-226 reference materials having a matrix similar to soil or tailings samples are not available in sufficient quantity for use by remedial-action contractors to calibrate their laboratory gamma-ray spectrometers. Such reference materials are needed to provide uniform standardization among measurements made by remedial-action contractors. A task, therefore, was undertaken to prepare about 200 pounds each of three different concentrations of radium-226 reference materials by diluting tailings with high-purity silica. Target values for radium-226 content were 50, 15, and 5 pCi/g. The radium-226 content of the reference materials was measured by C.W. Sill of EG and G Idaho, Inc., Idaho Falls, using a high- resolution alpha spectrometry technique standardized with National Bureau of Standards (NBS) standard 4961. A summary of this technique is provided in Appendix A of this report. An independent measurement of the radium-226 content was conducted by Bendix Field Engineering Corporation (Bendix), Grand Junction, Colorado, using a high-resolution Ge(Li) detector, which was calibrated using the New Brunswick Laboratory (NBL) 100-A Series standards. The Ge(Li) detector has also been used to determine the radium-226 content in the calibration models at the Grand Junction facility; these models are used by remedial-action contractors for calibration of borehole logging gamma-ray probes. 8 references, 12 tables.

  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 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.

  6. 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.

  7. Estimation of radon emanation coefficient for representative soils in Okinawa, Japan.

    PubMed

    Shiroma, Y; Hosoda, M; Ishikawa, T; Sahoo, S K; Tokonami, S; Furukawa, M

    2015-11-01

    Radon ((222)Rn) emanation coefficients for the representative soils distributed in Okinawa Island, Japan, have been estimated empirically. Arithmetic means of the emanation coefficients for dry and moist conditions were calculated to be 0.19 and 0.29, respectively. In Okinawa, the soils are traditionally classified into three types, namely the dark red soils, the residual regosols and the red and yellow soils. The dark red soils have relatively high coefficients. The residual regosols and the red and yellow soils have relatively low coefficients. To investigate the variable factor of the emanation coefficients, analyses of radioactive elements and physical properties have also been performed on the soils. For the dark red soils, the contents of the fine particle and the (226)Ra are relatively higher than those for the other soils. Based on these results, it is suggested that the variation in the radon emanation coefficient is mainly regulated by the (226)Ra concentration, the particle sizes and the water contents of the soils.

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

    PubMed

    López-Coto, I; Mas, J L; Vargas, A; Bolívar, J P

    2014-09-15

    Nearly 1.0 × 10(8) tonnes of phosphogypsum were accumulated during last 50 years on a 1,200 ha disposal site near Huelva town (SW of Spain). Previous measurements of exhalation rates offered very variable values, in such a way that a worst case scenario could not be established. Here, new experimental data coupled to numerical simulations show that increasing the moisture contents or the temperature reduces the exhalation rate whilst increasing the radon potential or porosity has the contrary effect. Once the relative effects are compared, it can be drawn that the most relevant parameters controlling the exhalation rate are radon potential (product of emanation factor by (226)Ra concentration) and moisture saturation of PG. From wastes management point of view, it can be concluded that piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. Furthermore, a proposed cover here is expected to allow exhalation rates reductions up to 95%. We established that the worst case scenario corresponds to a situation of extremely dry winter. Under these conditions, the radon exhalation rate (0.508 Bqm(-2)s(-1)) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bqm(-2)s(-1)).

  9. High sensitivity radon emanation measurements.

    PubMed

    Zuzel, G; Simgen, H

    2009-05-01

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

  10. Occurrence of mammary tumors in beagls given radium-226

    SciTech Connect

    Bruenger, F.W.; Lloyd, R.D.; Miller, S.C.; Taylor, G.N.; Angus, W.; Huth, D.A.

    1994-06-01

    A total of 128 primary mammary tumors (66 of them malignant) occurred in 35 female beagles injected with {sup 226}Ra at eight dose levels ranging from 0.2 to 440 kBq/kg body mass as young adults, while a total of 156 mammary tumors (57 of them malignant) were seen in 46 female control beagles not given any radioactivity. Sixty-three of 65 control dogs and 59 of 61 dogs given {sup 226}Ra survived the minimum age for diagnosis of mammary tumors of 3.75 years. Based on the observed age-dependent tumor incidence rates in the controls and on the corresponding number of dog-years at risk, the total number of observed malignant tumors in the radium group was statistically greater than the number of expected malignant tumors (66 observed vs 34 expected, P < 0.005). There was no such difference for the benign tumors. Cox regression analysis indicated no increased risk for the first tumor occurrence in irradiated dogs. Cox regression analysis of the multivariate risk sets showed no significantly increased risk for the occurrence of benign tumors but a statistically higher risk of 1.66 with a confidence interval of 1.15-2.40 for the occurrence of malignant tumors. The increased risk was dependent on dose, but a dependence on the frequency of previous occurrence of mammary tumors could not be confirmed. Censoring ovariectomized dogs at time of surgery decreased the relative risks slightly but did not alter the significance. Exposure to diagnostic X rays with cumulative exposures below 0.2 Gy had no effect on tumor formation. It is unknown whether the increased risk for malignant mammary tumors was due to some initial deposition of radium in sensitive tissue, a possible irradiation of fatty mammary tissue from transient radon {yields} polonium deposition, or a general effect of the overall radium deposition on the immune system of the dogs that lowered their resistance to formation of mammary tumors. 27 refs., 5 figs., 4 tabs.

  11. Radon, Smoking, and Lung Cancer: The Need to Refocus Radon Control Policy

    PubMed Central

    Mendez, David; Philbert, Martin A.

    2013-01-01

    Exposure to radon is the second leading cause of lung cancer, and the risk is significantly higher for smokers than for nonsmokers. More than 85% of radon-induced lung cancer deaths are among smokers. The most powerful approach for reducing the public health burden of radon is shaped by 2 overarching principles: public communication efforts that promote residential radon testing and remediation will be the most cost effective if they are primarily directed at current and former smokers; and focusing on smoking prevention and cessation is the optimal strategy for reducing radon-induced lung cancer in terms of both public health gains and economic efficiency. Tobacco control policy is the most promising route to the public health goals of radon control policy. PMID:23327258

  12. 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.

  13. Method for collecting radon and testing therefor

    SciTech Connect

    Addison, C.D.

    1992-04-21

    This patent describes a method of collecting radon in a confined area for the removal and testing thereof. It comprises providing a container having an open inlet end closed by a removably sealable lid means, the container being filled with a molecular sieve material which has the inherent characteristics of attracting radon, the container having a perforated plate removably mounted in its upper end, the perforation being of a size smaller than the molecular sieve material to prevent removal of the material yet permit the flow of air therethrough, placing the container in the confined area, removing the sealable lid to reveal the open inlet end of the container, watching a predetermined period of time with the container in the confined area, whereby at least a portion of any radon in the area will be attracted to the molecular sieve material in the container which will substantially remain therein, resealing the lid on the container, removing the container from the confined area so that the molecular sieve material may be tested for the presence of radon and so that any radon may be removed from the area, testing the molecular sieve material for radon, and subjecting the molecular sieve material to temperatures high enough to purge the material of radon.

  14. Observations of surface radon in Central Italy

    NASA Astrophysics Data System (ADS)

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

    2009-07-01

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

  15. 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. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  16. Nanomaterial containing wall paints can increase radon concentration in houses located in radon prone areas.

    PubMed

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

    2013-09-01

    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. This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. 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. 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/m(3) while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m(3). The difference between these means was statistically significant (P<0.001). 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.

  17. 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

  18. 21 CFR 226.1 - Current good manufacturing practice.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Current good manufacturing practice. 226.1 Section...) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES General Provisions § 226.1 Current good manufacturing practice. (a) The criteria in §§ 226.10 through 226.115,...

  19. 21 CFR 226.1 - Current good manufacturing practice.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Current good manufacturing practice. 226.1 Section...) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES General Provisions § 226.1 Current good manufacturing practice. (a) The criteria in §§ 226.10 through 226.115,...

  20. 21 CFR 226.1 - Current good manufacturing practice.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Current good manufacturing practice. 226.1 Section...) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES General Provisions § 226.1 Current good manufacturing practice. (a) The criteria in §§ 226.10 through 226.115,...