Science.gov

Sample records for radon daughter monitor

  1. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present....

  2. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present....

  3. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present....

  4. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present....

  5. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present....

  6. Residential radon daughter monitor based on alpha spectroscopy

    SciTech Connect

    Nazaroff, W.W.

    1980-05-01

    The radioactive daughters of radon-222 pose a serious indoor air quality problem in some circumstances. A technique for measuring the concentrations of these radioisotopes in air is presented. The method involves drawing air through a filter; then, for two time intervals after sampling, counting the alpha decays from polonium-218 and polonium-214 on the filter. The time intervals are optimized to yield the maximum resolution between the individual daughter concentrations. For a total measurement time of 50 minutes, individual daughter concentrations of 1.0 nanocuries per cubic meter are measured with an uncertainty of 20%. A prototype of a field monitor based on this technique is described, as is a field test in which the prototype was used to measure radon daughter concentrations as a function of ventilation conditions in an energy-efficient house.

  7. Orphan radon daughters at Denver Radium site

    SciTech Connect

    Holub, R.F.; Droullard, R.F.; Davis, T.H.

    1992-12-31

    During 18 mo of sampling airborne radioactively at a National Priority List ({open_quotes}Superfund{close_quotes}) site in metroPOlitan Denver, Bureau of mines personnel discovered radon daughters that are not supported by the parent radon gas. We refer to them as {open_quotes}orphan{close_quotes} daughters because the parent, radon, is not present in sufficient concentration to support the measured daughter products. Measurements of the {open_quotes}orphan{close_quotes} daughters were made continuously, using the Bureau-developed radon and working-level (radon-daughter) monitors. The data showed high equilibrium ratios, ranging from 0.7 to 3.5, for long periods of time. Repeated, high-volume, 15-min grab samples were made, using the modified Tsivoglou method, to measure radon daughters, to which thoron daughters contributed 26 {+-} 12%. On average 28 {+-} 6% of the particulate activity was contributed by thoron daughters. Most samples were mixtures in which the {sup 218}Po concentration was lower than that of {sup 214}Pb and {sup 214}Bi, in agreement with the high-equilibrium factors obtained from the continuous sampling data. In view of the short half-life of radon progeny, we conclude that the source of the orphan daughters is not far from the Superfund sites. The mechanism of this phenomenon is not understood at this time, but we will discuss its possible significance in evaluating population doses.

  8. 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)

  9. 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)

  10. 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.

  11. Radon and radon daughter levels in energy efficient housing.

    PubMed

    McGregor, R G; Walker, W B; Létourneau, E G

    1985-10-01

    Radon and radon daughter concentrations have been measured in 33 "energy-efficient" homes in a small subdivision in Kanata, Ontario. Integrated radon measurements were determined over three month periods for a year using solid state nuclear track detectors. Radon and radon daughter grab sample determinations were made during corresponding periods and confirm the distributions of the integrated radon measurements. Annual average individual home radon concentrations show an 8 fold concentration range between homes. This variability in radon concentrations is not reflected in the range of air exchange rates for the homes. A distinct seasonal variation is noted for the median values of the radon and radon daughter concentrations and the equilibrium factor F in the dwellings.

  12. Contribution of radon and radon daughters to respiratory cancer

    SciTech Connect

    Harley, N.; Samet, J.M.; Cross, F.T.; Hess, T.; Muller, J.; Thomas, D.

    1986-12-01

    This article reviews studies on the contribution of radon and radon daughters to respiratory cancer and proposes recommendations for further research, particularly a national radon survey. The steady-state outdoor radon concentration averages 200 pCi/m3, and indoor levels are about 4 times higher. The primary source of radon in homes is the underlying soil; entry depends on multiple variables and reduced ventilation for energy conservation increases indoor radon levels. Occupational exposures are expressed in units of radon daughter potential energy concentration or working level (WL). Cumulative exposure is the product of the working level and the time exposed. The unit for cumulative exposure is the working level month (WLM). The occupational standard for radon exposure is 4 WLM/year, and 2 WLM/year has been suggested as a guideline for remedial action in homes. Epidemiologic studies show that miners with cumulative radon daughter exposures somewhat below 100 WLM have excess lung cancer mortality. Some 3% to 8% of miners studied have developed lung cancer attributable to radon daughters. All of the underground mining studies show an increased risk of lung cancer with radon daughter exposure. All cell types of lung cancer increased with radon exposure. If radon and smoking act in a multiplicative manner, then the risk for smokers could be 10 times that for nonsmokers. The potential risk of lung cancer appears to be between 1 and 2 per 10,000/WLM, which yields a significant number of lung cancers as some 220 million persons in the United States are exposed on average to 10 to 20 WLM/lifetime.

  13. 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

  14. Radon and radon daughter measurements in solar buildings.

    PubMed

    George, A C; Knutson, E O; Franklin, H

    1983-08-01

    Measurements of radon and radon daughters in 11 buildings in five states, using active or passive solar heating, showed no significant excess in concentrations over the levels measured in buildings with conventional heating systems. Radon levels in two buildings using rock storage in their active solar systems exceeded the U.S. Nuclear Regulatory Commission's limit of 3 pCi/l. for continuous exposure in uncontrolled areas. In the remainder of the buildings, radon concentrations were found to be at levels considered to be normal. It appears that the slightly elevated indoor radon concentrations result from the local geological formations and from the tightening of the buildings rather than as a result of the solar heating technology. PMID:6885442

  15. (Mutagenicity of radon and radon daughters)

    SciTech Connect

    Not Available

    1990-01-01

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

  16. 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.

  17. 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.

  18. 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.

  19. 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

  20. Radon-daughter exposures in energy-efficient buildings

    SciTech Connect

    Nero, A.V.; Berk, J.V.; Boegel, M.L.; Hollowell, C.D.; Ingersoll, J.G.; Nazaroff, W.W.

    1981-10-01

    A radon concentration of 1 pCi/1 (37 Bq/m/sup 3/) appears to lie in the range that is typical for air inside US residential buildings. Moreover, some US residences have concentrations higher than 1 pCi/1, sometimes by an order of magnitude, implying significant individual risk to occupants. For typical radon daughter equilibrium ratios, this concentration corresponds to a radon daughter exposure rate of 0.2 working level months (WLM) per year. This exposure rate may account for a significant lung cancer incidence if data on lung cancers per unit exposure in miners are applicable to such low exposures. Reductions in air exchange rates may rise the typical exposure rate and even increase it to unacceptable levels in some cases. Measures that reduce energy use by reducing natural infiltration or mechanical ventilation in new or retrofit buildings are therefore undergoing severe scrutiny. Lawrence Berkeley Laboratory has performed measurements in buildings specifically designed to use energy efficiently or utilize solar heating. In many of these buildings radon concentrations appear to arise primarily from soil underlying the buildings. Measures to control higher levels, e.g., by mechanical ventilation with heat recuperation, appear to be economical. However, to evaluate energy-saving programs adequately requires a much more comprehensive characterization of radon sources (for example, by geographical area) and a much fuller understanding of the dynamics of radon and its daughters indoors than now exist.

  1. Multagenicity of radon and radon daughters. Final technical report, January 1, 1993--December 31, 1996

    SciTech Connect

    Evans, H.H.

    1997-06-01

    The objective of this research was to investigate the dose-response relationship with regard to the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose-rate dependence was studied, as well as the nature of the DNA lesions. The effect of DNA repair on the lethal and mutagenic effects of exposure and on the character of the DNA lesions was investigated by comparing the response of L5178Y strains that differ in their ability to rejoin X radiation-induced DNA double strand breaks. The nature of radon/radon daughter-induced mutational lesions in human lymphoblasts was also investigated.

  2. A continuous plutonium aerosol monitor for use in high radon environments.

    PubMed

    Li, HuiBin; Jia, MingYan; Li, GuoShen; Wang, YinDong

    2012-01-01

    Radon concentration is very high in underground basements and other facilities. Radon concentration in a nuclear facility locates in the granite tunnel can be as high as 10(4) Bq m(-3) in summer. Monitoring plutonium aerosol in this circumstance is seriously interfered by radon daughters. In order to solve this problem, a new continuous aerosol monitor that can monitor very low plutonium aerosol concentration in high radon background was developed. Several techniques were used to reduce interference of radon daughters, and the minimum detectable concentrations in various radon concentrations were measured.

  3. Carcinogenic and cocarcinogenic effects of radon and radon daughters in rats

    SciTech Connect

    Monchaux, G.; Morlier, J.P.; Morin, M.; Lafuma, J.; Masse, R. ); Chameaud, J. )

    1994-01-01

    It has been previously established that lung cancer could be induced in rats by exposure to radon and radon daughters. Although the oat-cell carcinomas that are common in humans were not found in rats, other histological types of lung carcinomas, especially squamous cell carcinomas and primitive lung adenocarcinomas, were similar to those observed in humans. A dose-effect relationship was established for cumulative doses varying from 25 to 300 working-level-months (WLM), which was similar for medium and high cumulative doses to that observed in uranium miners. This experimental protocol was also used to study the potential cocarcinogenic effects of other environmental or industrial airborne pollutants such as tobacco smoke, mineral fibers, diesel exhausts, or minerals from metallic mine ores that may act synergistically with radon exposure. In rats exposed to radon and tobacco smoke combined, the incidence of malignant thoracic tumors was observed in rats exposed to radon and fibers combined, but synergistic effects resulted in additivity. With diesel exhausts or minerals from metallic ores, a slight, nonsignificant increase in the incidence of lung carcinomas was observed compared with rats exposed to radon alone. These results demonstrated that it is possible to establish the potential cocarcinogenic action, showing either multiplicative, additive, or no effect of various environmental or industrial airborne pollutants combined with radon exposure. This radon model is valid for investigating possible interactions between two occupational exposures. 62 refs., 6 figs., 9 tabs.

  4. Carcinogenic and Cocarcinogenic Effects of Radon and Radon Daughters in Rats.

    PubMed Central

    Monchaux, G; Morlier, JP; Morin, M; Chameaud, J; Lafuma, J; Masse, R

    1994-01-01

    It has been previously established that lung cancer could be induced in rats by exposure to radon and radon daughters. Although the oat-cell carcinomas that are common in humans were not found in rats, other histological types of lung carcinomas, especially squamous cell carcinomas and primitive lung adenocarcinomas, were similar to those observed in humans. A dose-effect relationship was established for cumulative doses varying from 25 to 3000 working-level-months (WLM), which was similar for medium and high cumulative doses to that observed in uranium miners. This experimental protocol was also used to study the potential cocarcinogenic effects of other environmental or industrial airborne pollutants such as tobacco smoke, mineral fibers, diesel exhausts, or minerals from metallic mine ores that may act synergistically with radon exposure. In rats exposed to radon and tobacco smoke combined, the incidence of lung cancers was higher by a factor of 2-4 according to the cumulative radon exposure and the duration of tobacco smoke exposure. When mineral fibers were injected intrapleurally, an increased incidence of malignant thoracic tumors was observed in rats exposed to radon and fibers combined, but synergistic effects resulted in additivity. With diesel exhausts or minerals from metallic ores, a slight, nonsignificant increase in the incidence of lung carcinomas was observed compared with rats exposed to radon alone. These results demonstrated that it is possible to establish the potential cocarcinogenic action, showing either multiplicative, additive, or no effect of various environmental or industrial airborne pollutants combined with radon exposure. This radon model is valid for investigating possible interactions between two occupational exposures. Images p64-a Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. PMID:9719670

  5. Domestic and personal determinants of the contamination of individuals by household radon daughters

    SciTech Connect

    Stebbings, J.H.; Kardatzke, D.R.; Toohey, R.E.; Essling, M.E.; Pagnamenta, A.

    1986-01-01

    Radon daughters were counted by gamma spectroscopy from 180 adult residents of eastern Pennsylvania during the winter of 1983-84. Body radon daughter contamination is an index of relative individual respiratory exposures to radon daughters. These can be related to household radon levels, and to personal risk factors such as sex and tobacco smoking. Over 75% of this Pennsylvania population appeared to have environmentally enhanced radon daughter contamination; 59% had counting rates greater than 2 s.d. above background. House radon levels were the major determinants of radon daughters contamination in the 112 subjects for which both sets of measurements were available (p<.001). Both sex (<.02) and cigarette smoking (p<.005) were found to significantly modify that relationship, after nonlinear adjustment for travel times. Using a logarithmic model, for a given radon level body contamination by radon daughters in females was 2-3.5x higher than in males. Nonsmokers had 2-4x higher levels of contamination than smokers. For female nonsmokers relative to male smokers (which in general corresponds to the population of major concern relative to the population from which risk estimates have been derived), the excesses multiply. These results are for total contamination, both internal and external.

  6. Experiences and concerns on lung cancer and radon daughter exposure in mines and dwellings in Sweden.

    PubMed

    Axelson, O

    1983-01-01

    A high mortality from lung cancer among miners was reported from Central Europe already in the 19th century. In the 60s and 70s several reports have indicated an increased lung cancer mortality among uranium miners and other metal-miners, e.g. in the US, UK, France and Sweden, but also among fluorspar miners in Canada. The cause is supposed to be the decay products of radon as emanating from the rocks, i.e. the alpha-radiation from short-lived radon daughters. Radon and radon daughter exposure in dwellings have more recently attracted interest as a potential hazard to the general population, especially since radon daughter concentrations seem to have increased due to more effective insulation for energy saving. In many Swedish houses the radon daughter exposures amount to levels similar to that of mines. Some epidemiological evaluations of the relationship between lung cancer and exposure to radon daughters, i.e. residency in stone houses versus wooden houses (with and without consideration of the contribution of radon from the ground underneath the houses), seem to indicate a risk also to the general population and, moreover, the risk of smoking seems to be several times greater in stone houses than in wooden houses, the latter usually having less radon daughters on the average.

  7. Reduction of radon daughter concentrations in structures. [UMTRA project

    SciTech Connect

    Not Available

    1982-12-01

    A structure was identified in Salt Lake City wherein uranium mill tailings had been used in the construction and where unusually high levels of radon daughter concentrations (RDC's) existed. The physical and radiological characteristics of the structure were assessed. Ventilation techniques were investigated to assess their effectiveness in reducing RDC's. A preferred set of equipment was identified, installed in the structure and operated to reduce RDC's. Parametric studies were conducted to determine if supplying fresh air or recirculating air through electrostatic precipitators is more effective in reducing RDC's. Fresh air was found to be more effective in reducing RDC's. RDC's have been reduced to levels at or near the target of 0.03 working level under optimal ventilation conditions. Natural gas consumption with the new equipment is about 39% higher than with the original equipment. Electrical energy usage and electrical demand are respectively 50 and 44% higher with the new equipment than with the original equipment. 16 refs., 14 figs., 8 tabs.

  8. Alpha particle spectra and microdosimetry of radon daughters

    SciTech Connect

    Caswell, R.S.; Coyne, J.J.

    1992-12-31

    We are interested in understanding the physics of the process by which radon-daughter alpha particles irradiate cells, leading to the induction of cancer. We are focusing initially on two aspects: the alpha spectra incident upon cells, which are needed for input to biophysical models of cancer induction; and microdosimetric spectra and parameters which give information on radiation quality. Adapting an analytical method previously developed for neutron radiation, we have calculated the alpha-particle slowing-down spectra (the spectra incident upon cells) and, subsequently, the microdosimetric spectra and parameters for various cell nuclei or site diameters. Results will be presented from three modes of program operation. MODE 1 is for the thin, plane source of radon-daughter activity adjacent to the epithelium. MODE 2 is for the thick source layer (the mucous-serous layer) adjacent to the epithelium. MODE4 is for cylindrical airways of various radii, lined by the mucous-serous layer. MODE 1 is most useful for understanding the problem; MODE 4 is most anatomically relevant. MODE 3 is not discussed in this paper. Alpha-particle spectra and microdosimetric spectra and parameters are studied as a function of cell depth, {sup 218}Po/{sup 214}Po ratio, airway radius, and cell nucleus or the site size. Also available from the calculation is mean dose as a function of depth below the airway surface. The results described here are available on personal computer diskettes. We are beginning to compare our studies with the calculations of other workers and plan to extend the calculations to the nanometer target level.

  9. Energy deposition and radiation quality of radon and radon daughters. Final report

    SciTech Connect

    Karam, L.R.; Caswell, R.S.

    1996-09-09

    This program was aimed at creating a quantitative physical description, at the micrometer and nanometer levels, of the physical interactions of the alpha particles from radon and its daughters with cells at risk in the bronchial epithelium. The authors calculated alpha-particle energy spectra incident upon the cells and also energy deposition spectra in micrometer- and nanometer-sized sites as a function of cell depth, site size, airway diameter, activities of {sup 218}Po and {sup 214}Po, and other parameters. These data are now being applied, using biophysical models of radiation effects, to predict cell killing, mutations, and cell transformation. The model predictions are then compared to experimental biophysical, biochemical, and biological information. These studies contribute to a detailed understanding of the mechanisms of the biological effectiveness of the radiations emitted by radon and its progeny.

  10. Lung cancer mortality among nonsmoking uranium miners exposed to radon daughters

    SciTech Connect

    Roscoe, R.J.; Steenland, K.; Halperin, W.E.; Beaumont, J.J.; Waxweiler, R.J.

    1989-08-04

    Radon daughters, both in the workplace and in the household, are a continuing cause for concern because of the well-documented association between exposure to radon daughters and lung cancer. To estimate the risk of lung cancer mortality among nonsmokers exposed to varying levels of radon daughters, 516 white men who never smoked cigarettes, pipes, or cigars were selected from the US Public Health Service cohort of Colorado Plateau uranium miners and followed up from 1950 through 1984. Age-specific mortality rates for nonsmokers from a study of US veterans were used for comparison. Fourteen deaths from lung cancer were observed among the nonsmoking miners, while 1.1 deaths were expected, yielding a standardized mortality ratio of 12.7 with 95% confidence limits of 8.0 and 20.1. These results confirm that exposure to radon daughters in the absence of cigarette smoking is a potent carcinogen that should be strictly controlled.

  11. A facility for studying the carcinogenic and synergistic effects of radon daughters and other agents in rodents

    SciTech Connect

    Strong, J.C.; Walsh, M.

    1992-12-31

    Although there is evidence to link lung cancer with radon exposures in miners, studies have not yet adequately demonstrated a link at domestic levels of exposure. Induction of cancer in animals after acute exposure to high levels of radon and radon daughters has been investigated by several laboratories. It is our intention to study the effects of radon and its daughters on rodents following both acute and chronic exposure. The studies will be extended to investigate the effects of other carcinogens in association with radon daughters. We will describe a facility in which rodents can be exposed continuously to radon and its daughters for periods of up to several months. The facility consists of two exposure chambers with closed air circuits which are operated independently of each other. Aerosol generators provide controlled vector aerosols onto which radon daughters can attach. Particular attention has been paid to accurate measurements of the concentrations of radon gas and of individual radon daughters. Techniques have also been developed for measuring the {open_quotes}unattached{close_quotes} fraction, the activity size distribution of individual daughters, and the potential alpha energy. The environment within the facility will be adjusted to be comparable to that found in dwellings with regard to condensation nucleus concentration, {open_quotes}unattached{close_quotes} fraction, equilibrium factor, and activity size distribution. Other vapors and aerosols, such as tobacco smoke, can be introduced into one of the air circuits to study the combined effects of radiation and toxic chemical agents.

  12. Radon daughter levels in some public and private buildings in India.

    PubMed

    Khan, A J

    1991-10-01

    Radon daughter concentrations have been measured in some public and private buildings of Aligarh city. Approximately 320 CR-39 detectors were mounted in 30 sample sites. It was found that the Rn daughter concentrations vary from 3.5 mWL to 8.1 mWL with a geometric mean of 5.6 +/- 1.3 mWL. The average annual effective dose equivalent due to Rn daughters is found to be 1.46 mSv using an equilibrium factor of 0.45 and an occupancy factor of 0.8. About 33% of buildings were estimated to have a Rn concentration below 40 Bq m-3 and 79% below 60 Bq m-3. The measured levels do not require any intervention as recommended by the U.S. Environmental Protection Agency.

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

    PubMed

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

    2008-01-01

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

  14. Monitoring of Radon in Tourist Part of Skocjan Caves

    NASA Astrophysics Data System (ADS)

    Debevec Gerjevic, Vanja; Jovanovic, Peter

    2010-05-01

    Due to their exceptional significance for cultural and natural heritage, the Škocjan Caves were entered on UNESCO's list of natural and cultural world heritage sites in 1986. Park Škocjan Caves is located in South Eastern part of Slovenia. It was established with aim of conserving and protecting exceptional geomorphological, geological and hydrological outstanding features, rare and endangered plant and animal species, paleontological and archaeological sites, ethnological and architectural characteristics and cultural landscape and for the purpose of ensuring opportunities for suitable development, by the National Assembly of the Republic of Slovenia in 1996. Park Škocjan Caves established monitoring that includes caves microclimate parameters: humidity, CO2, wind flow and radon concentration and daughter products. The approach in managing the working place with natural background radiation is complex. Monitoring of Radon has been functioning for more than ten years now. Presentation will show the yearly dynamic observed in the different parts of the caves, related to radon daughter products and other microclimatic data, beside the most convenient measuring technique. Implementing the Slovene legislation in the field of radiation protection, we are obligated to perform special measurements in the caves and also having our guides and workers in the caves regularly examined according to established procedure. The medical exams are performed at Institution of Occupational Safety, Ljubljana in order to monitor the influence of Radon to the workers in the cave. The equivalent dose for each employed person is also established on regular basis and it is part of medical survey of workers in the caves. The survey will be described along with education of the staff working in the caves in the field of radiation protection. An overview of Slovene legislation with practical example on implementation will be demonstrated in the case of Škocjan Caves where the managing

  15. [The methods of assessment of health risk from exposure to radon and radon daughters].

    PubMed

    Demin, V F; Zhukovskiy, M V; Kiselev, S M

    2014-01-01

    The critical analysis of existing models of the relationship dose-effect (RDE) for radon exposure on human health has been performed. Conclusion about the necessity and possibility of improving these models has been made. A new improved version ofthe RDE has been developed. A technique for assessing the human health risk of exposure to radon, including the method for estimating of exposure doses of radon, an improved model of RDE, proper methodology risk assessment has been described. Methodology is proposed for the use in the territory of Russia.

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

    SciTech Connect

    Laurer, G.R.; Cohen, N. . Dept. of Environmental Medicine); Stark, A.; Ju, C. . Bureau of Environmental and Occupational Epidemiology)

    1991-05-01

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

  17. 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

  18. The Study of Equilibrium factor between Radon-222 and its Daughters in Bangkok Atmosphere by Gamma-ray Spectrometry

    NASA Astrophysics Data System (ADS)

    Rujiwarodom, Rachanee

    2010-05-01

    To study the Equilibrium between radon-222 and its daughters in Bangkok atmosphere by Gamma-ray spectrometry, air sample were collected on 48 activated charcoal canister and 360 glass fiber filters by using a high volume jet-air sampler during December 2007 to November 2008.The Spectra of gamma-ray were measured by using a HPGe (Hyper Pure Germanium Detector). In the condition of secular equilibrium obtaining between Radon-222 and its decay products, radon-222 on activated charcoal canister and its daughters on glass fiber filters collected in the same time interval were calculated. The equilibrium factor (F) in the open air had a value of 0.38 at the minimum ,and 0.75 at the maximum. The average value of equilibrium factor (F) was 0.56±0.12. Based on the results, F had variations with a maximum value in the night to the early morning and decreased in the afternoon. In addition, F was higher in the winter than in the summer. This finding corresponds with the properties of the Earth atmosphere. The equilibrium factor (F) also depended on the concentration of dust in the atmosphere. People living in Bangkok were exposed to average value of 30 Bq/m3 of Radon-222 in the atmosphere. The equilibrium factor (0.56±0.12) and the average value of Radon-222 showed that people were exposed to alpha energy from radon-222 and its daughters decay at 0.005 WL(Working Level) which is lower than the safety standard at 0.02 WL. Keywords: Radon, Radon daughters , equilibrium factor, Gamma -ray spectrum analysis ,Bangkok ,Thailand

  19. Radon Monitoring Results BPA Residential Weatherization Program, Report Number 1.

    SciTech Connect

    United States. Bonneville Power Administration.

    1986-01-01

    In October 1984, the Bonneville Power Administration (BPA) began offering free radon monitoring to participants of its regionwide Residential Weatherization Program. The purpose of the radon monitoring is to provide information to participating homeowners or consumers on the average radon concentrations within their residences. This radon concentration information and other information on indoor air quality (IAQ) is provided to assist homeowners on their decision to install ''house-tightening'' weatherization measures. This radon report will present background information on why BPA decided to offer radon monitoring, the procedures used for monitoring, the extent of BPA radon monitoring in the region, and results of this monitoring. Subsequent BPA radon monitoring reports will be produced on a quarterly basis which will include a brief narrative on the radon monitoring and provide a summary of the radon data received to date.

  20. International intercomparison of measuring instruments for radon/thoron gas and radon short-lived daughter products in the NRPI Prague.

    PubMed

    Jílek, K; Hýža, M; Kotík, L; Thomas, J; Tomášek, L

    2014-07-01

    During the 7th European Conference on Protection Against Radon at Home and at Work held in the autumn of 2013 in Prague, the second intercomparison of measuring instruments for radon and its short-lived decay products and the first intercomparison of radon/thoron gas discriminative passive detectors in mix field of radon/thoron were organised by and held at the Natural Radiation Division of the National Radiation Protection Institute (NRPI) in Prague. In total, 14 laboratories from 11 different countries took part in the 2013 NRPI intercomparison. They submitted both continuous monitors for the measurement of radon gas and equivalent equilibrium radon concentration in a big NRPI chamber (48 m3) and sets of passive detectors including radon/thoron discriminative for the measurement of radon gas in the big chamber and thoron gas in a small thoron chamber (150 dm3).

  1. Characteristics of attached radon-222 daughters under both laboratory and underground uranium-mine environments

    SciTech Connect

    Jackson, P.O.; Cooper, J.A.; Langford, J.C.; Petersen, M.R.

    1981-09-01

    The organic, inorganic, and radiological characteristics of airborne aerosols have been measured as a function of particle size in controlled atmosphere test chambers and operating uranium mines. Concentrations of benzo(a)pyrene in two mines ranged from 26 to 57 ng/m/sup 3/ of air. The carbon chain length of adsorbed n-alkanes was correlated with particle size. Normal mining activities produced an ore dust aerosol with mass median aerodynamic diameter (MMAD) greater than 2 ..mu..m. The elements Na, Al, Si, K, Ca, Ti, V, Fe, and U exhibited elemental ratios similar to bulk ore and had comparable MMAD's. The S, Zn, and Pb were higher in aerosols than bulk ore and were associated with smaller MMAD particulates. Radon daughter particle size distributions were influenced by the kinds of particulates generated in mining activity.

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

    SciTech Connect

    Laurer, G.R.; Cohen, N. . Inst. of Environmental Medicine); Stark, A.; Ju, C. . Bureau of Environmental and Occupational Epidemiology)

    1990-10-01

    The feasibility of measuring Pb-210 in vivo in the skulls of those individuals who have resided in homes with above average levels of radon/radon daughters, has now been successfully demonstrated. These values, when incorporated into metabolic models of Pb-210 in the body including other related physical parameters, can be used for the calculation of a realistic estimate of a resident's cumulative exposure to radon and its' decay products. Data are presented for 26 subjects exposed to higher than average concentrations of radon i.e. ranging from 10 to 120 pCi/l, for various periods of time. Their skeletal Pb-210 burdens are compared to measurement results of a population of individuals presumed to have been exposed to values which are more representative of average levels i.e. <1pCi/1. Results of a study to determine the biological retention of Pb-210 in the human skeleton for use in the metabolic model relating skull burdens of this nuclide to cumulative radon/daughter exposure, are also described. At the present time, our measurements, made over a period of 10 years, of an individual with a significant Pb-210 burden, indicate a biological half-time of approximately 57 years and an effective half-life of 16 years. 4 refs., 11 figs.

  3. Atmospheric injection of radon daughters from the 1982 eruption of El Chichon volcano

    SciTech Connect

    Liou, J.C.H.

    1983-01-01

    Radiochemical measurements of the concentrations of /sup 210/Pb and /sup 210/Po have been carried out for individual samples of rain and snow which were collected at Fayetteville (36/sup 0/N,94/sup 0/W), Arkansas, during the period between August 1981 and September 1982, in an attempt to elucidate the effect of the 28 March 1982 eruption of El Chichon volcano in Mexico on the atmospheric inventories of the long-lived radon daughters. A sharp increase in the concentration of /sup 210/Pb was observed in the 31 March 1982 rain, but the effect of the volcano eruption was not clearly noticeable in the concentration of /sup 210/Po in rain and the /sup 210/Po//sup 210/Pb ratio in rain showed a marked decrease after the 28 March 1982 event. The observed patterns of variation of the concentrations and the ratios of long-lived radon daughers in rain were somewhat analogous to those observed after the 18 May 1980 eruption of Mount St. Helens: a marked increase in the /sup 210/Po//sup 210/Pb ratio in rain was observed during the months of January and February 1981, more than seven months after the 18 May 1980 event, indicating that excess /sup 210/Po from the eruption of Mount St. Helens was injected primarily into the stratosphere. An order of magnitude calculation of the total amount of /sup 210/Po released into the atmosphere by the eruption of Mount St. Helens was carried out and a value of 2.1 x 10/sup 4/ Ci was obtained. This value is comparable to the estimate made by Lambert et al. (1982) for the atmospheric production of /sup 210/Po (3 x 10/sup 4/ Ci) and it corresponds to about 23% of their estimate of the total world-wide deposition of /sup 210/Po per year.

  4. 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.

  5. Natural distribution of environmental radon daughters in the different brain areas of an Alzheimer Disease victim

    PubMed Central

    Momčilović, Berislav; Lykken, Glenn I; Cooley, Marvin

    2006-01-01

    Background Radon is a ubiquitous noble gas in the environment and a primary source of harmful radiation exposure for humans; it decays in a cascade of daughters (RAD) by releasing the cell damaging high energy alpha particles. Results We studied natural distribution of RAD 210Po and 210Bi in the different parts of the postmortem brain of 86-year-old woman who had suffered from Alzheimer's disease (AD). A distinct brain map emerged, since RAD distribution was different among the analyzed brain areas. The highest RAD irradiation (mSv·year-1) occurred in the decreasing order of magnitude: amygdale (Amy) >> hippocampus (Hip) > temporal lobe (Tem) ~ frontal lobe (Fro) > occipital lobe (Occ) ~ parietal lobe (Par) > substantia nigra (SN) >> locus ceruleus (LC) ~ nucleus basalis (NB); generally more RAD accumulated in the proteins than lipids of gray and white (gray > white) brain matter. Amy and Hip are particularly vulnerable brain structure targets to significant RAD internal radiation damage in AD (5.98 and 1.82 mSv·year-1, respectively). Next, naturally occurring RAD radiation for Tem and Fro, then Occ and Par, and SN was an order of magnitude higher than that in LC and NB; the later was within RAD we observed previously in the healthy control brains. Conclusion Naturally occurring environmental RAD exposure may dramatically enhance AD deterioration by selectively targeting brain areas of emotions (Amy) and memory (Hip). PMID:16965619

  6. Outdoor Radon--Sources, Monitoring and Risk Assessment

    SciTech Connect

    Bulko, M.; Holy, K.; Mullerova, M.; Simon, J.

    2007-11-26

    Various sources of atmospheric radon, as well as the results of radon monitoring at the Faculty of Mathematics, Physics and Informatics (FMFI CU) campus are discussed. The evaluation of the risk caused by radon and its decay products in the Bratislava atmosphere is given.

  7. Radon Dosimetry and Monitoring in Mines

    NASA Astrophysics Data System (ADS)

    Pineau, J. F.

    The following sections are included: * Introduction * The Atmosphere in Underground Mines * Origin of the radioactivity of the atmosphere in underground mines * Main characteristics of the atmosphere of mines * Temperature * Relative humidity * Particle size distribution of the aerosols * Volume concentration of radon * Age of the ventilation air * Volume concentration of radon decay products * Volume concentration of long-lived aerosols (LLA) * Order of magnitude of the volume concentrations to be measured * Dosimetry: Application to Miners * Dosimetry of miners in France * Integrated dosimetry system * Measuring head * Unit for the detection and measurement of exposure to potential alpha energy * Treatment and reading of the detector films * Expression of the results * Other examples of operational dosimetry * Use of closed passive dosimeters for the dosimetry of miners * Monitoring of Physical Parameters of the Atmospheres * Qualification of non-uranium mines * Monitoring of the environment of mining sites * Optimisation of radiation protection using the dosimetric data * Concluding Remarks * References

  8. In-vivo measurements of Pb-210 to determine cumulative exposure to radon daughters: A pilot study. Final report, 1 March, 1990--May 31, 1991

    SciTech Connect

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

    1991-05-01

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

  9. Ambient Radon-222 Monitoring in Amargosa Valley, Nevada

    SciTech Connect

    L.H. Karr; J.J. Tappen; D. Shafer; K.J. Gray

    2008-06-05

    As part of a program to characterize and baseline selected environmental parameters in the region around the proposed repository at Yucca Mountain, Nevada, ambient radon-222 monitoring was conducted in the rural community of Amargosa Valley, the community closest to the proposed repository site. Passive integrating radon monitors and a continuous radon monitoring instrument were deployed adjacent to the Community Environmental Monitoring Program (CEMP) (http://www.cemp.dri.edu/index.html) station located in the Amargosa Valley Community Center near the library. The CEMP station provided real-time ambient gamma exposure and meteorological data used to correct the integrated radon measurements as well as verify meteorological data collected by the continuous radon monitoring instrument. Additionally, different types of environmental enclosures that housed the monitors and instrument were used to determine if particular designs influenced the ambient radon measurements.

  10. The radon monitoring system in Daya Bay Reactor Neutrino Experiment

    NASA Astrophysics Data System (ADS)

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

    2016-02-01

    We developed a highly sensitive, reliable and portable automatic system (H3) to monitor the radon concentration of the underground experimental halls of the Daya Bay Reactor Neutrino Experiment. H3 is able to measure radon concentration with a statistical error less than 10% in a 1-h measurement of dehumidified air (R.H. 5% at 25 °C) with radon concentration as low as 50 Bq/m3. This is achieved by using a large radon progeny collection chamber, semiconductor α-particle detector with high energy resolution, improved electronics and software. The integrated radon monitoring system is highly customizable to operate in different run modes at scheduled times and can be controlled remotely to sample radon in ambient air or in water from the water pools where the antineutrino detectors are being housed. The radon monitoring system has been running in the three experimental halls of the Daya Bay Reactor Neutrino Experiment since November 2013.

  11. Performance comparison of electronic radon monitors.

    PubMed

    Lin, Chi-Feng; Wang, Jeng-Jong; Lin, Shih-Jung; Lin, Chien-Kung

    2013-11-01

    The electronic radon monitors are noted for their convenience and acceptable accuracy. Even so, it is necessary to reassure their data quality regularly. We utilized a performance comparison system for this purpose. The instruments in our laboratories (Alphaguard, RAD7, RTM-2100 and Safety Siren) were tested via the comparison experiments. We conclude that by utilizing this system with the concept of calibration factor, it can be helpful to decide whether to send the monitors back to the original manufacturers for adjustment. PMID:23566805

  12. Deposition of {open_quotes}unattached{close_quotes} radon daughters in models of human nasal and oral airways

    SciTech Connect

    Strong, J.C.; Swift, D.L.

    1992-12-31

    In order to estimate accurately an effective dose equivalent for exposures to radon daughters, knowledge of their deposition in the lung is required. However, the nose and mouth are effective filters for removing aerosol particles, especially in the range of sizes of {open_quotes}unattached{close_quotes} radon daughters. Therefore, it is equally important to have reliable data on deposition in this region of the respiratory tract. We will describe our work in studying nasal and oral deposition of {open_quotes}unattached{close_quotes} radon daughters in casts of these airways. Several hollow casts of adult and child nasal and oral airways were fabricated at The John Hopkins University from layers of Perspect{trademark} (an acrylic plastic). The shapes of the airway passages were obtained from nuclear magnetic resonance sectional images of healthy subjects. The casts were exposed to radon gas and daughters produced by flushing filtered air through a commercially available {sup 226}Ra source. The gas stream was drawn through a 1.4-L cylindrical tube to allow measurable growth of {sup 218}Po activity before it was passed through casts of both nasal passages or the oral cavity. The deposition of {open_quotes}unattached{close_quotes} {sup 218}Po was measured by comparing the activity collected on filters mounted in series and in parallel with a cast. Measurements were made at various flow rates (Q; 4 to 20 L min{sup -1}). The diffusion coefficient (D) of {sup 218}Po was measured each time the flow rate was changed, by replacing the cast with a stainless steel gauze screen and measuring the activity penetrating the screen. The measured diffusion coefficient ranged from 0.02 to 0.05 cm{sup 2} s{sup -1} and was found to vary with the residence time of {sup 218}Po in the growth tube. The deposition efficiency ({eta}) of {sup 218}Po measured in these casts ranged from 50 to 70%, and was similar to values we found previously, using casts of nasal and oral airways from cadavers.

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

    PubMed

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

    2014-12-01

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

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

    PubMed

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

    2014-12-01

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

  15. Instrumentation for a radon research house

    SciTech Connect

    Nazaroff, W.W.; Revzan, K.L.; Robb, A.W.

    1981-07-01

    A highly automated monitoring and control system for studying radon and radon-daughter behavior in residences has been designed and built. The system has been installed in a research house, a test space contained in a two-story wood-framed building, which allows us to conduct controlled studies of (1) pollutant transport within and between rooms, (2) the dynamics of radon daughter behavior, and (3) techniques for controlling radon and radon daughters. The system's instrumentation is capable of measuring air-exchange rate, four-point radon concentration, individual radon daughter concentrations, indoor temerature and humidity, and outdoor weather parameters (temperature, humidity, modules, wind speed, and wind direction). It is also equipped with modules that control the injection of radon and tracer gas into the test space, the operation of the forced-air furnace, the mechanical ventilation system, and the mixing fans located in each room. A microcomputer controls the experiments and records the data on magnetic tape and on a printing terminal. The data on tape is transferred to a larger computer system for reduction and analysis. In this paper we describe the essential design and function of the instrumentation system, as a whole, singling out those components that measure ventilation rate, radon concentration, and radon daughter concentrations.

  16. Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

    SciTech Connect

    Fabrikant, J.I.

    1982-06-01

    The quantitative estimation of the carcinogenic risk of low-dose, high-LET radiation in the case of exposure to radon daughters and lung-cancer is subject to numerous uncertainties. The greatest of these concerns the parametric values of the dose-response curve. We lack knowledge and an understanding of the dosimetry and the distribution of aggregates of radioactivity that remain localized as hot spots in specific regions of the lungs and the influence on greater or lesser risk of lung cancer per average lung dose than uniformly deposited radiation (NRC76). We have only a limited understanding of the response to exposure to high-LET radiations, such as alpha particles, for which linear risk estimates for low doses are less likely to overestimate the risk, and may, in fact, underestimate the risk (BEIR80). Other uncertainties include the length of the latency period, the RBE for alpha radiation relative to gamma radiation, the period during which the radiation risk is expressed, the risk projection model used - whether absolute or relative - for projecting risk beyond the period of observation, the effect of dose rate and protraction of dose, and the influence of differences in the natural incidence of lung cancer in different populations. In addition, uncertainties are introduced by the biological and life-style risk characteristics of humans, for example, the effect of sex, the effect of age at the time of irradiation and at the time of appearance of the cancer, the influence of length of observation or follow-up of the study populations, and the influence of perhaps the most important confounding bias, cigarette-smoking. The collective influence of these uncertainties is such as to deny great credibility to any estimate of human lung cancer risk and other cancer risk that can be made for low-dose, high-LET radon daughter radiation exposure.

  17. Fernald radon stack monitor user`s guide

    SciTech Connect

    Whitley, C.R.

    1997-01-01

    The stack monitor uses long-range alpha detection (LRAD) technology for the measurement of radon levels in the stack emissions. The basic principle behind LRAD is the collection of ions created in air through the energy loss mechanisms of decay alphas. This is accomplished by establishing an electric field in the region where alpha decays will occur, and directing the ions via the field onto a biased plate. Accumulation of charge on the plate results in a current in the biasing circuit which can be read with a sensitive electrometer. In electrostatic LRAD designs, the linearity of the measured current with gross alpha activity is well-established. In order to determine radon-222 levels in the presence of other radon isotopes, it is necessary to perform some type of isotopic analysis on the stack samples. In the present case, other radon isotopes of possible concern are radon-219, which occurs in the decay chain of uranium-235, and radon-220, found in the decay chain of thorium-232. Radon-219, with a half-life of four seconds, presents no difficulty for the situation in which emanations from the vitrification process undergo as little as one minute of delay before release into the stack. For example, an initial concentration of 200,000 pCi/l of radon-219 decays to 5 pCi/l in one minute. Radon-220, however, has a half-life of about 55 seconds. If initially present in a substantial ratio to radon-222, a radon gross-alpha measurement on stack emissions would have a significant error if used as a measure for radon-222, even with many minutes of processing delay before the sample was taken.

  18. Radon exhalation rates from building materials using electret ion chamber radon monitors in accumulators.

    PubMed

    Kotrappa, Payasada; Stieff, Frederick

    2009-08-01

    An electret ion chamber (EIC) radon monitor in a sealed accumulator measures the integrated average radon concentration at the end of the accumulation duration. Theoretical equations have been derived to relate such radon concentrations (Bq m(-3) ) to the radon emanation rate (Bq d(-1)) from building materials enclosed in the accumulator. As an illustration, a 4-L sealable glass jar has been used as an accumulator to calculate the radon emanation rate from different granite samples. The radon emanation rate was converted into radon flux (Bq mm(-2) d(-1)) by dividing the emanation rate by surface area of the sample. Fluxes measured on typical, commercially available granites ranged from 20-30 Bq m(-2) d(-1). These results are similar to the results reported in the literature. The lower limit of detection for a 2-d measurement works out to be 7 Bq m(-2) d(-1). Equations derived can also be used for other sealable accumulators and other integrating detectors, such as alpha track detectors.

  19. -spectroscopy investigation of radon daughter deposition on electrostatically charged surfaces

    NASA Astrophysics Data System (ADS)

    Batkin, I.; Brun del Re, R.; Boutin, J.-G.; Armitage, J.

    1998-03-01

    The effect of static electricity on the deposition of radon daughters onto charged surfaces is determined by a combined experimental and theoretical analysis. Experiments with charged surfaces exposed to the air in a normal working environment are analysed to determine an empirical radon daughter deposition rate. This factor is utilized to estimate the daughter deposition on a human head which is exposed to similar conditions of air quality and static charging. The results indicate that typical levels of static electricity can enhance the deposition of radon daughters by orders of magnitude compared with the uncharged condition. The corresponding yearly alpha dose equivalents to the basal skin layer and to the eye exceed recommended limits. Beside having an important impact from the public health perspective, these results suggest that the obscure and contradictory correlations found between radon concentrations and adverse health effects may arise from a failure to account for the effects of static electricity.

  20. Home radon monitor modeled after the common smoke detector

    SciTech Connect

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

    1995-02-01

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

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

    NASA Astrophysics Data System (ADS)

    Piersanti, Antonio; Cannelli, Valentina; Galli, Gianfranco

    2016-09-01

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

  2. The radon problem

    NASA Astrophysics Data System (ADS)

    Crameri, Reto; Burkart, Werner

    The importance of the radon problem is illustrated by the fact that the indoor exposure to radon and radon daughters amounts to about 40% of the total effective dose equivalent to which the population is exposed to both, from natural and man made sources. This exposure may increase even further due to new building technologies optimized for energy conservation. Although radon and its decay products are well known to cause lung cancer at high exposure levels, considerable controversy remains about the magnitude of risk due to low-level exposure. Linear extrapolation from the dose-response values of uranium miners who were heavily exposed to these nuclides would suggest that a relevant fraction (10-40%) of lung cancers in the general population are caused by the inhalation of radon daughters. Moreover, the results of monitoring programs in several countries during the past years have revealed that for a small, but not negligible fraction of the population, the lifetime exposure from indoor radon daughters is comparable to, or even exceeds the occupational radon exposure of moderately exposed underground miners still showing a significant excess lung cancer frequency.

  3. Radon

    MedlinePlus

    ... with elevated radon underwent changes to reduce radon pollution. 1 How Can Radon Be Detected? The only ... Association Applauds EPA’s Update to Cross-State Air Pollution Rule News: New Truck Efficiency Standards Expected to ...

  4. Control of contamination of radon-daughters in the DEAP-3600 acrylic vessel

    NASA Astrophysics Data System (ADS)

    Jillings, Chris; DEAP Collaboration

    2013-08-01

    DEAP-3600 is a 3600kg single-phase liquid-argon dark matter detector under construction at SNOLAB with a sensitivity of 10-46cm2 for a 100 GeV WIMP. The argon is held an an acrylic vessel coated with wavelength-shifting 1,1,4,4-tetraphenyl-1,3-butadiene (TPB). Acrylic was chosen because it is optically transparent at the shifted wavelength of 420 nm; an effective neutron shield; and physically strong. With perfect cleaning of the acrylic surface before data taking the irreducible background is that from bulk 210Pb activity that is near the surface. To achieve a background rate of 0.01 events in the 1000-kg fiducial volume per year of exposure, the allowed limit of Pb-210 in the bulk acrylic is 31 mBq/tonne (= 1.2 × 10-20g/g). We discuss how pure acrylic was procured and manufactured into a complete vessel paying particular attention to exposure to radon during all processes. In particular field work at the acrylic panel manufacturer, RPT Asia, and acrylic monomer supplier, Thai MMA Co. Ltd, in Thailand is described. The increased diffusion of radon during annealing the acrylic at 90C as well as techniques to mitigate against this are described.

  5. Control of contamination of radon-daughters in the DEAP-3600 acrylic vessel

    SciTech Connect

    Jillings, Chris; Collaboration: DEAP Collaboration; and others

    2013-08-08

    DEAP-3600 is a 3600kg single-phase liquid-argon dark matter detector under construction at SNOLAB with a sensitivity of 10{sup −46}cm{sup 2} for a 100 GeV WIMP. The argon is held an an acrylic vessel coated with wavelength-shifting 1,1,4,4-tetraphenyl-1,3-butadiene (TPB). Acrylic was chosen because it is optically transparent at the shifted wavelength of 420 nm; an effective neutron shield; and physically strong. With perfect cleaning of the acrylic surface before data taking the irreducible background is that from bulk {sup 210}Pb activity that is near the surface. To achieve a background rate of 0.01 events in the 1000-kg fiducial volume per year of exposure, the allowed limit of Pb-210 in the bulk acrylic is 31 mBq/tonne (= 1.2 × 10{sup −20}g/g). We discuss how pure acrylic was procured and manufactured into a complete vessel paying particular attention to exposure to radon during all processes. In particular field work at the acrylic panel manufacturer, RPT Asia, and acrylic monomer supplier, Thai MMA Co. Ltd, in Thailand is described. The increased diffusion of radon during annealing the acrylic at 90C as well as techniques to mitigate against this are described.

  6. Effects of Elevated Radon Levels on Kanne Tritium Monitors

    SciTech Connect

    Farrell, W.E.

    2003-11-24

    The Savannah River Site has used Kanne ionization chambers since the late 1950's to monitor for airborne tritium in reactor facilities. Two Kanne monitors indicated elevated airborne tritium levels while monitoring a non-ventilated room used to store tritiated liquid moderator. Subsequent air sample analysis failed to reveal the presence of airborne tritium. It was suspected that elevated radon levels caused the Kanne monitors to falsely indicate tritium activity. Two commercially available monitoring systems were used to quantify radon levels in the storage room. Measurements performed during this evaluation found that radon caused the Kanne monitors in the storage room to falsely indicate the presence of airborne tritium. A side-by-side comparison of a filtered versus an unfiltered Kanne monitor found that a high efficiency particulate filter reduced monitor response to near background under high radon conditions. It was recommended that a high efficiency filter be installed on the dedicated storage room Kanne monitor and that the room be de-posted as an Airborne Radioactivity Area. It was also found that the Kanne monitors would detect a spill from a single drum of moderator within minutes and the dose rate due to tritium exposure at 20 hours following this spill would be 4.56 rem/hour.

  7. Developments in real-time radon monitoring at Stromboli volcano.

    PubMed

    Laiolo, M; Cigolini, C; Coppola, D; Piscopo, D

    2012-02-01

    We present the results of one year of continuous radon monitoring at Stromboli volcano collected at two automated real-time stations. These were deployed on the NE flank (at 520 m a.s.l.) and within the summit area (900 m a.s.l.). Higher daily emissions at the lower station approached 4,200 Bq/m³, with bulk averages around 1,800 (±980) Bq/m³; whereas the summit station reached peak values of 23,000 Bq/m³ and bulk averages of 12,500 Bq/m³ (±4,000). Negative correlations are observed between radon emissions, soil temperature and, to a lesser extent, atmospheric pressure. In contrast, increases in radon concentrations were observed during periods of higher rainfall conditions. Therefore, trends in radon concentrations may be decoupled from those of other geochemical parameters (CO₂ fluxes and CO₂/SO₂ plume ratios) during periods of heavy to moderate rainfalls. Multiple Linear Regression statistics (including the effects of soil temperature, atmospheric pressure and tidal forces) led us to compute the residuals given by the difference of measured and calculated ²²²Rn concentrations. The cross-check between the daily measured radon activities and the absolute variations in radon residuals, for the data collected at the summit station, give us the opportunity to suggest a methodological approach that can be used in the attempt of predicting some major changes in volcanic activity. PMID:22230018

  8. Developments in real-time radon monitoring at Stromboli volcano.

    PubMed

    Laiolo, M; Cigolini, C; Coppola, D; Piscopo, D

    2012-02-01

    We present the results of one year of continuous radon monitoring at Stromboli volcano collected at two automated real-time stations. These were deployed on the NE flank (at 520 m a.s.l.) and within the summit area (900 m a.s.l.). Higher daily emissions at the lower station approached 4,200 Bq/m³, with bulk averages around 1,800 (±980) Bq/m³; whereas the summit station reached peak values of 23,000 Bq/m³ and bulk averages of 12,500 Bq/m³ (±4,000). Negative correlations are observed between radon emissions, soil temperature and, to a lesser extent, atmospheric pressure. In contrast, increases in radon concentrations were observed during periods of higher rainfall conditions. Therefore, trends in radon concentrations may be decoupled from those of other geochemical parameters (CO₂ fluxes and CO₂/SO₂ plume ratios) during periods of heavy to moderate rainfalls. Multiple Linear Regression statistics (including the effects of soil temperature, atmospheric pressure and tidal forces) led us to compute the residuals given by the difference of measured and calculated ²²²Rn concentrations. The cross-check between the daily measured radon activities and the absolute variations in radon residuals, for the data collected at the summit station, give us the opportunity to suggest a methodological approach that can be used in the attempt of predicting some major changes in volcanic activity.

  9. 40 CFR 61.203 - Radon monitoring and compliance procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. EPA shall be notified at... stack in accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. The stack... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Radon monitoring and...

  10. 40 CFR 61.203 - Radon monitoring and compliance procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. EPA shall be notified at... stack in accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. The stack... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Radon monitoring and...

  11. 40 CFR 61.203 - Radon monitoring and compliance procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. EPA shall be notified at... stack in accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. The stack... 40 Protection of Environment 8 2011-07-01 2011-07-01 false Radon monitoring and...

  12. 40 CFR 61.203 - Radon monitoring and compliance procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. EPA shall be notified at... stack in accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. The stack... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Radon monitoring and...

  13. 40 CFR 61.203 - Radon monitoring and compliance procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. EPA shall be notified at... stack in accordance with the procedures described in 40 CFR part 61, appendix B, Method 115. The stack... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Radon monitoring and...

  14. Radon

    MedlinePlus

    You can't see radon. And you can't smell it or taste it. But it may be a problem in your home. Radon comes from the natural breakdown of uranium in soil, rock, and water. Radon is the second leading cause of lung cancer ...

  15. Measurement systems and indices of miners' exposure to radon daughter products in the air of mines.

    PubMed

    Domański, T

    1990-01-01

    This paper presents the classification of measurement systems that may be used for the assessment of miners' exposure to radiation in mines. The following systems were described and characterized as the Air Sampling System (ASS), the Environmental Control System (ECS), the Individual Dosimetry System (IDS), the Stream Monitoring System (SMS) and the Exhaust Monitoring System (EMS). The indices for evaluation of miners' working environments, or for assessment of individual or collective miners' exposure, were selected and determined. These are: average expected concentration (CAE), average observed concentration (CAO), average expected rate of exposure cumulation rate (EEXP), average observed exposure cumulation rate (EOBS), average effective exposure cumulation rate (EEFF). Mathematical formulae for determining all these indicators, according to the type of measurement system used in particular mines, are presented. The reliability of assessment of miners' exposure in particular measurement systems, as well as the role of the possible reference system, are discussed. PMID:2134320

  16. 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.

  17. 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.

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

    PubMed

    Ringer, W

    2014-07-01

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

  19. The most recent international intercomparisons of radon and thoron monitors with the NIRS radon and thoron chambers.

    PubMed

    Janik, M; Yonehara, H

    2015-06-01

    The fifth international intercomparison for radon and fourth for thoron monitors were conducted at National Institute of Radiological Sciences (Japan) with the radon and thoron chambers. The tests were made under two different exposures to radon and two exposures (in two rounds due to limited space in the thoron chamber) to thoron. In these most recent intercomparisons, two new graphical methods recommended by the ISO standard, Mandel's h statistic and the Youden plot, were implemented to evaluate the consistency between laboratories and within laboratories.The presented data indicated that the performance quality of laboratories for radon measurement as expressed by the percentage difference parameter has been stable since the first international intercomparison for passive monitors carried out in 2007, and it amounted to around 50 for 10 % of the difference from the reference value. The thoron exercise showed that further development and additional studies to improve its measuring methods and reliability are needed.

  20. Soil radon monitoring in the NE flank of Mt. Etna (Sicily).

    PubMed

    Immè, G; La Delfa, S; Lo Nigro, S; Morelli, D; Patanè, G

    2006-05-01

    Soil radon has been monitored at a fixed location on the northeastern flank of Mt. Etna, a high-risk volcano in Sicily. The aim of this study was to evaluate the effects of the recent volcanic activity on soil radon concentration. Continuous radon measurements have been performed since July 2001. While comparison between the trend in in-soil radon concentration and the acquired meteorological series (temperature, humidity and pressure) appear to confirm a general seasonal correlation, nevertheless particular anomalies suggest a possible dependence of the radon concentration on volcanic dynamics. PMID:16413194

  1. Soil radon monitoring in the NE flank of Mt. Etna (Sicily).

    PubMed

    Immè, G; La Delfa, S; Lo Nigro, S; Morelli, D; Patanè, G

    2006-05-01

    Soil radon has been monitored at a fixed location on the northeastern flank of Mt. Etna, a high-risk volcano in Sicily. The aim of this study was to evaluate the effects of the recent volcanic activity on soil radon concentration. Continuous radon measurements have been performed since July 2001. While comparison between the trend in in-soil radon concentration and the acquired meteorological series (temperature, humidity and pressure) appear to confirm a general seasonal correlation, nevertheless particular anomalies suggest a possible dependence of the radon concentration on volcanic dynamics.

  2. Radon Monitoring and Early Low Background Counting at the Sanford Underground Laboratory

    SciTech Connect

    Thomas, K. J.; Mei, D.-M.; Heise, J.; Durben, D.; Salve, R.

    2011-04-27

    Radon detectors have been deployed underground at the Sanford Underground Laboratory at the site of the former Homestake Mine in Lead, SD. Currently, no radon mitigation measures are in place in the underground environment, and the continuing evolution of the facility ventilation systems has led to significant variations in early airborne radon concentrations. The average radon concentration measured near the primary ventilation intake for the 4850-ft level (Yates shaft) is 391 Bq/m{sup 3}, based on approximately 146 days of data. The corresponding average radon concentration near the other main ventilation intake for the 4850-ft level (Ross shaft) is 440 Bq/m{sup 3} based on approximately 350 days of data. Measurements have also been collected near the 1250-ft level Ross shaft, with average radon concentrations at 180 Bq/m{sup 3}. Secondary factors that may increase the baseline radon level underground include the presence of iron oxide and moisture, which are known to enhance radon emanation. The results of the current radon monitoring program will be used for the planning of future measurements and any potential optimization of ventilation parameters for the reduction of radon in relevant areas underground.

  3. Radon monitoring and early low background counting at the Sanford Underground Laboratory

    SciTech Connect

    Thomas, K.J.; Mei, D.M.; Heise, J.; Durben, D.; Salve, R.

    2010-09-01

    Radon detectors have been deployed underground at the Sanford Underground Laboratory at the site of the former Homestake Mine in Lead, SD. Currently, no radon mitigation measures are in place in the underground environment, and the continuing evolution of the facility ventilation systems has led to significant variations in early airborne radon concentrations. The average radon concentration measured near the primary ventilation intake for the 4850-ft level (Yates shaft) is 391 Bq/m{sup 3}, based on approximately 146 days of data. The corresponding average radon concentration near the other main ventilation intake for the 4850-ft level (Ross shaft) is 440 Bq/m{sup 3} based on approximately 350 days of data. Measurements have also been collected near the 1250-ft level Ross shaft, with average radon concentrations at 180 Bq/m{sup 3}. Secondary factors that may increase the baseline radon level underground include the presence of iron oxide and moisture, which are known to enhance radon emanation. The results of the current radon monitoring program will be used for the planning of future measurements and any potential optimization of ventilation parameters for the reduction of radon in relevant areas underground.

  4. An Algorithm for Source Checking Continuous Air Monitors Using Radon Progeny

    SciTech Connect

    Hogue, M.G.

    2000-03-06

    Department of Energy requirements contained within 10CFR835 require that continuous air monitors be periodically checked for operability. The DOE air monitoring implementation guide for 10CFR835 allows the use of radon progeny to perform the recommended weekly source check. The Defense Waste Processing Facility located at the Savannah River Site has demonstrated that, through the use of the Hypotheses Concerning Two Means, diurnal changes in the radon progeny detected by the monitors meets the requirements for weekly source checks. The use of the diurnal changes in radon progeny has replaced the man-hours expended performing direct weekly source checking with an automated system requiring minimal man-hour expenditure.

  5. Invited article: radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan.

    PubMed

    Janik, M; Ishikawa, T; Omori, Y; Kavasi, N

    2014-02-01

    Inhalation of radon ((222)Rn) and its short-lived decay products and of products of the thoron ((220)Rn) series accounts for more than half of the effective dose from natural radiation sources. At this time, many countries have begun large-scale radon and thoron surveys and many different measurement methods and instruments are used in these studies. Consequently, it is necessary to improve and standardize technical methods of measurements and to verify quality assurance by intercomparisons between laboratories. Four international intercomparisons for passive integrating radon and thoron monitors were conducted at the NIRS (National Institute of Radiological Sciences, Japan). Radon exercises were carried out in the 24.4 m(3) inner volume walk-in radon chamber that has systems to control radon concentration, temperature, and humidity. Moreover, the NIRS thoron chamber with a 150 dm(3) inner volume was utilized to provide three thoron intercomparisons. At present, the NIRS is the only laboratory world-wide that has carried out periodic thoron intercomparison of passive monitors. Fifty laboratories from 26 countries participated in the radon intercomparison, using six types of detectors (charcoal, CR-39, LR 115, polycarbonate film, electret plate, and silicon photodiode). Eighteen laboratories from 12 countries participated in the thoron intercomparisons, using two etch-track types (CR-39 and polycarbonate) detectors. The tests were made under one to three different exposures to radon and thoron. The data presented in this paper indicated that the performance quality of laboratories for radon measurement has been gradually increasing. Results of thoron exercises showed that the quality for thoron measurements still needs further development and additional studies are needed to improve its measuring methods. The present paper provides a summary of all radon and thoron international intercomparisons done at NIRS from 2007 to date and it describes the present status on

  6. Invited Article: Radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan

    NASA Astrophysics Data System (ADS)

    Janik, M.; Ishikawa, T.; Omori, Y.; Kavasi, N.

    2014-02-01

    Inhalation of radon (222Rn) and its short-lived decay products and of products of the thoron (220Rn) series accounts for more than half of the effective dose from natural radiation sources. At this time, many countries have begun large-scale radon and thoron surveys and many different measurement methods and instruments are used in these studies. Consequently, it is necessary to improve and standardize technical methods of measurements and to verify quality assurance by intercomparisons between laboratories. Four international intercomparisons for passive integrating radon and thoron monitors were conducted at the NIRS (National Institute of Radiological Sciences, Japan). Radon exercises were carried out in the 24.4 m3 inner volume walk-in radon chamber that has systems to control radon concentration, temperature, and humidity. Moreover, the NIRS thoron chamber with a 150 dm3 inner volume was utilized to provide three thoron intercomparisons. At present, the NIRS is the only laboratory world-wide that has carried out periodic thoron intercomparison of passive monitors. Fifty laboratories from 26 countries participated in the radon intercomparison, using six types of detectors (charcoal, CR-39, LR 115, polycarbonate film, electret plate, and silicon photodiode). Eighteen laboratories from 12 countries participated in the thoron intercomparisons, using two etch-track types (CR-39 and polycarbonate) detectors. The tests were made under one to three different exposures to radon and thoron. The data presented in this paper indicated that the performance quality of laboratories for radon measurement has been gradually increasing. Results of thoron exercises showed that the quality for thoron measurements still needs further development and additional studies are needed to improve its measuring methods. The present paper provides a summary of all radon and thoron international intercomparisons done at NIRS from 2007 to date and it describes the present status on radon and

  7. Invited Article: Radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan

    SciTech Connect

    Janik, M. Ishikawa, T.; Omori, Y.; Kavasi, N.

    2014-02-15

    Inhalation of radon ({sup 222}Rn) and its short-lived decay products and of products of the thoron ({sup 220}Rn) series accounts for more than half of the effective dose from natural radiation sources. At this time, many countries have begun large-scale radon and thoron surveys and many different measurement methods and instruments are used in these studies. Consequently, it is necessary to improve and standardize technical methods of measurements and to verify quality assurance by intercomparisons between laboratories. Four international intercomparisons for passive integrating radon and thoron monitors were conducted at the NIRS (National Institute of Radiological Sciences, Japan). Radon exercises were carried out in the 24.4 m{sup 3} inner volume walk-in radon chamber that has systems to control radon concentration, temperature, and humidity. Moreover, the NIRS thoron chamber with a 150 dm{sup 3} inner volume was utilized to provide three thoron intercomparisons. At present, the NIRS is the only laboratory world-wide that has carried out periodic thoron intercomparison of passive monitors. Fifty laboratories from 26 countries participated in the radon intercomparison, using six types of detectors (charcoal, CR-39, LR 115, polycarbonate film, electret plate, and silicon photodiode). Eighteen laboratories from 12 countries participated in the thoron intercomparisons, using two etch-track types (CR-39 and polycarbonate) detectors. The tests were made under one to three different exposures to radon and thoron. The data presented in this paper indicated that the performance quality of laboratories for radon measurement has been gradually increasing. Results of thoron exercises showed that the quality for thoron measurements still needs further development and additional studies are needed to improve its measuring methods. The present paper provides a summary of all radon and thoron international intercomparisons done at NIRS from 2007 to date and it describes the

  8. Parentification, substance use, and sex among adolescent daughters from ethnic minority families: the moderating role of monitoring.

    PubMed

    Sang, Jina; Cederbaum, Julie A; Hurlburt, Michael S

    2014-06-01

    Guided by structural family systems theory, this study explored the relationship between parentification and adolescent daughters' sexual risk engagement and substance use. We also explored how adolescent reports of parental monitoring moderated the relationship between parentification and adolescent risk. Data were from a cross-sectional, cross-generational study of 176 mother-daughter dyads from low-income, inner-city, ethnic minority families. In this sample, which included a subset of mothers with HIV, parental physical symptoms were associated with slightly higher levels of parentification. Parentification was associated with adolescent daughters' intention to have sex (but not substance use) in a direction opposite to prediction. Higher parentification was associated with lower intention to have sex. Parental monitoring did not moderate relationships between parentification and adolescent risk. These findings highlight that despite the negative influence hypothesized in structural family systems theory, parentification was not associated with risk engagement of high-risk adolescent daughters in ethnic minority families with low income.

  9. Indoor radon.

    PubMed

    Polpong, P; Bovornkitti, S

    1998-01-01

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

  10. Indoor radon.

    PubMed

    Polpong, P; Bovornkitti, S

    1998-01-01

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

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

    NASA Astrophysics Data System (ADS)

    Nazaroff, William W.

    1983-09-01

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

  12. 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...

  13. 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...

  14. 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.

  15. Long-term monitoring of soil gas radon and permeability at two reference sites.

    PubMed

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

    2008-01-01

    The long-term monitoring of soil radon variations was conducted at two reference sites in Ottawa. The purpose of this study was to determine whether a single soil radon survey could provide a representative soil radon characteristic of the site. Results showed that during the normal field survey period from June to September in Canada, a single field survey with multiple measurements of soil gas radon concentrations at a depth of 80 cm can characterise the soil radon level of a site within a deviation of +/-30%. Direct in situ soil permeability measurements exhibited, however, large variations even within an area of only 10 x 10 m(2). Considering such large variations and the weight of the equipment, soil permeability can be determined by direct measurements whenever possible or by other qualitative evaluation methods for sites that are hard to access with heavy equipment.

  16. Soil radon monitoring in the Krsko Basin, Slovenia.

    PubMed

    Zmazek, B; Zivcić, M; Vaupotic, J; Bidovec, M; Poljak, M; Kobal, I

    2002-04-01

    In order to support the safe operation of the Krsko Nuclear Power Plant (Westinghouse, 676 MWe PWR), the seismotectonic structure of the Krsko basin has been thoroughly investigated. As part of a wider study, a study on radon in soil gas was started in April 1999. Combined barasol detectors buried in six boreholes, two along the Orlica fault and four on either side of it, measure and record radon activity, temperature and pressure every 60 min. The results have been evaluated and the possibility of a correlation with seismic activity is discussed. Correlation between radon concentration and barometric pressure has been observed for all barasols. Preliminary results show that, at one location, the correlation coefficient between radon and barometric pressure changed sign before earthquakes.

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

    SciTech Connect

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

    2012-07-01

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

  18. 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)

  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. Radon Monitoring and Emanation Studies at the Sanford Underground Laboratory at Homestake

    NASA Astrophysics Data System (ADS)

    Thomas, Keenan; Mei, Dongming; Heise, Jaret; Durben, Dan; Homestake Background Char. Team

    2011-10-01

    In anticipation of low-background nuclear and particle astrophysics experiments to be situated underground at the Sanford Underground Laboratory at Homestake our group has been researching factors relevant to radon underground at the Homestake Mine in Lead, SD. Continuous airborne monitoring of radon concentrations have been performed along the primary ventilation routes underground. Such measurements are useful for understanding the behavior of radon underground with respect to various ventilation conditions and will be of use in the design of experiments and underground laboratory infrastructure. In addition, iron oxide has been found to enhance the emanation of radon due to the co-precipitation of radium in the oxide layer. After decommissioning in 2003, the lower levels of the mine were allowed to fill with water, which prompted the formation of iron oxide upon submerged rock surfaces. A series of measurements including radon emanation tests have been performed upon rock and iron oxide samples to demonstrate this effect upon the airborne radon underground at Homestake. Supported by NSF PHY-0758120 and 0919278.

  1. Monitoring of atmospheric gamma radiation and radon observations of rainfall events in southeast of Brazil

    NASA Astrophysics Data System (ADS)

    Martin, I. M.; Alves, M. A.; Gomes, M. P.

    2013-05-01

    It is well known that we live in an environment that is under the influence of radioactivity. Radioactive elements in Earth's crust, cosmic rays, and anthropogenic sources contribute to the radiation of different types (alpha, beta, gamma and X-rays) that can be measured. An interesting phenomenon associated with environmental radioactivity is radon washout wherein the radon gas that is produced by the decay of natural radioactive elements and released into the atmosphere is concentrated near ground by falling rain. Rain drops trap radon in their interior and transport this radioactive gas to the surface. In this study, we describe the monitoring of the localized and temporary increase in the natural radioactivity caused by radon washout using a 3"x 3" NaI(Tl) scintillator. Variations in the radioactivity were correlated with changes in meteorological conditions. We observed that even though rainfall is a main factor in the increase of natural radioactivity near ground, other factors such as the presence of fog and winds play an important role in the concentration and dispersion of radon. Because of the low cost of our experimental set up, we believe that this is an experiment that could easily be conducted in most universities and could also be used to monitor environmental radioactivity levels.

  2. Radon monitoring using long-range alpha detector-based technology

    SciTech Connect

    Bolton, R.D.

    1994-11-01

    Long-Range Alpha Detector (LRAD) technology is being studied for monitoring radon gas concentrations. LRAD-based instruments collect and measure the ionization produced in air by alpha decays. These ions can be moved to a collection grid via electrostatic ion-transport design collected approximately 95% of the radon produced ions, while instruments using an airflow transport design collected from 44% to 77% of these ions, depending on detector geometry. The current produced by collecting this ionization is linear with respect to {sup 222}Rn concentration over the available test range of 0.07 to 820 pCi/L. In the absence of statistical limitations due to low radon concentrations, the speed of response of LRAD-based instruments is determined by the air exchange rate, and therefore changes in radon concentration can be detected in just a few seconds. Recent tests show that at radon concentrations below 20 pCi/L current pulses produced by individual alpha decays can be counted, thus improving detector sensitivity and stability even further. Because these detectors are simple, rugged, and do not consume much power, they are natural candidates for portable, battery operation.

  3. On the calibration of a radon exhalation monitor based on the electrostatic collection method and accumulation chamber.

    PubMed

    Tan, Yanliang; Tokonami, Shinji; Hosoda, Masahiro

    2015-06-01

    The radon exhalation rate can be obtained quickly and easily from the evolution of radon concentration over time in the accumulation chamber. Radon monitoring based on the electrostatic collection method is not interfered with by (220)Rn. In this paper, we propose that the difference between radon and (218)Po concentrations in the measurement cell of this kind of radon exhalation monitor is the main system error, and it changes with time and different effective decay constants. Based on the results of simulation experiments, we propose that the calibration factor obtained from the suitable experiment cannot completely correct the system error, even if it is useful to reduce the measurement error. The better way for reducing measurement error is to use the new measurement model which we have proposed in recent years.

  4. New study on the correlation between carbon dioxide concentration in the environment and radon monitor devices.

    PubMed

    Shahrokhi, A; Burghele, B D; Fábián, F; Kovács, T

    2015-12-01

    The influence of high geogenic carbon dioxide concentrations on monitoring devices might present a significant challenge to the measurement of radon concentrations in environments with a high level of carbon dioxide concentration such as volcano sites, mofettes, caves, etc. In this study, the influence of carbon dioxide concentration on several different types of radon monitor devices - including Alpha Spectrometry (Sarad RTM 2200, EQF 3220, RAD7), Ionizing Chamber (AlphaGUARD PQ2000 PRO) and Active Cell (Active scintillation cell, Pylon 300A) - was examined to represent new aspects of radon measuring in environments with carbon dioxide. In light of the results, all measuring devices were exposed to variable conditions affected by carbon dioxide concentration, except for the AlphaGUARD, which was kept in a steady state throughout the experiment. It was observed that alpha spectroscopy devices were affected by carbon dioxide, since measured radon concentrations decreased in the presence of 70% and 90% carbon dioxide concentrations by 26.5 ± 2% and 14.5 ± 2.5% for EQF 3220, and 32 ± 2% and 35.5 ± 2% for RTM 2200. However, the ionizing chamber instrument was unaffected by changes in carbon dioxide concentration. It was determined that the RAD7 performed relatively inefficiently in the presence of carbon dioxide concentrations higher than 67% by an overall efficiency factor of approximately 0.52, confirming that it is not an admissible radon monitor instrument in environments with high carbon dioxide concentrations.

  5. New study on the correlation between carbon dioxide concentration in the environment and radon monitor devices.

    PubMed

    Shahrokhi, A; Burghele, B D; Fábián, F; Kovács, T

    2015-12-01

    The influence of high geogenic carbon dioxide concentrations on monitoring devices might present a significant challenge to the measurement of radon concentrations in environments with a high level of carbon dioxide concentration such as volcano sites, mofettes, caves, etc. In this study, the influence of carbon dioxide concentration on several different types of radon monitor devices - including Alpha Spectrometry (Sarad RTM 2200, EQF 3220, RAD7), Ionizing Chamber (AlphaGUARD PQ2000 PRO) and Active Cell (Active scintillation cell, Pylon 300A) - was examined to represent new aspects of radon measuring in environments with carbon dioxide. In light of the results, all measuring devices were exposed to variable conditions affected by carbon dioxide concentration, except for the AlphaGUARD, which was kept in a steady state throughout the experiment. It was observed that alpha spectroscopy devices were affected by carbon dioxide, since measured radon concentrations decreased in the presence of 70% and 90% carbon dioxide concentrations by 26.5 ± 2% and 14.5 ± 2.5% for EQF 3220, and 32 ± 2% and 35.5 ± 2% for RTM 2200. However, the ionizing chamber instrument was unaffected by changes in carbon dioxide concentration. It was determined that the RAD7 performed relatively inefficiently in the presence of carbon dioxide concentrations higher than 67% by an overall efficiency factor of approximately 0.52, confirming that it is not an admissible radon monitor instrument in environments with high carbon dioxide concentrations. PMID:26281966

  6. Attachment of radon progeny to cigarette-smoke aerosols

    SciTech Connect

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

    1995-05-01

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

  7. Dose assessment to inhalation exposure of indoor 222Rn daughters in Korea.

    PubMed

    Ha, C W; Chang, S Y; Lee, B H

    1992-10-01

    Long-term, average indoor 222Rn concentrations were measured in 12 residential areas by passive CR-39 radon cups. Corresponding equilibrium-equivalent concentration of radon daughters were derived. The resulting effective dose equivalent for the Korean population due to inhalation exposure of this equilibrium-equivalent concentration of radon daughters was then evaluated.

  8. Radon isotope measurements as a monitoring tool for CO2 leakage in geological storage

    NASA Astrophysics Data System (ADS)

    Grandia, F.; Mazadiego, L. F.; de Elío, J.; Ortega, M.; Bruno, J.

    2011-12-01

    Early detection of the failure of the seal integrity is fundamental in the monitoring plan of a deep geological CO2 storage. A number of methods of leakage control are based on changes in fluid geochemistry (shallow water, soil gases) providing valuable indicators. Among them, the measurement of CO2 fluxes in the soil-atmosphere interface is commonly used since it can be easily done using portable infra-red analyzers (i.e., accumulation chambers). However, initial emission of CO2 from storage horizon could be masked by fluxes from biological activity, limiting its applicability as an early alarm system. The measurement of fluxes of trace gas (Rn, He, VOC) that are virtually absent in the pre-injection baseline turns out a promising complementary method. The measurement of radon isotopes has been long used for the observation of mass transport from deep reservoirs to surface despite the flux of 222Rn and 220Rn is usually very limited in sedimentary basins due to the short half-life of these isotopes. The enhanced transport of radon in CO2 fluxes has been reported from natural systems, resulting in concentration in air up to several thousands of Bq/m3. In the frame of the Compostilla pilot plant project in Spain, a number of methodologies to measure radon emission are being tested in natural systems to select of the most reliable and cost-effective method to be used in leakage control. These methods are (1) Scintillation detector EDA RD-200, (2) Track Etch °, (3) Ionization Chamber and (4) alpha spectroscopy SARAD RTM 200. Some of them are capable of measuring the isotopes separately (SARAD) whereas others just detect the bulk radon concentration. Also, these methods follow distinct procedures and acquisition times. The studied natural sites are located in central and NE Spain (Campo de Calatrava and La Selva basins), and in central Italy (Arezzo basin). Apparently, radon isotopes (up 200000 Bq/m3) are measured far from parent isotopes, and they are coupled to

  9. Filter for on-line air monitor unaffected by radon progeny and method of using same

    DOEpatents

    Phillips, Terrance D.; Edwards, Howard D.

    1999-01-01

    An apparatus for testing air having contaminants and radon progeny therein. The apparatus includes a sampling box having an inlet for receiving the air and an outlet for discharging the air. The sampling box includes a filter made of a plate of sintered stainless steel. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough. A method of testing air having contaminants and radon progeny therein. The method includes providing a testing apparatus that has a sampling box with an inlet for receiving the air and an outlet for discharging the air, and has a sintered stainless steel filter disposed within said sampling box; drawing air from a source into the sampling box using a vacuum pump; passing the air through the filter; monitoring the contaminants trapped by the filter; and providing an alarm when a selected level of contaminants is reached. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough.

  10. Effects of exposure uncertainty on estimation of radon risks

    SciTech Connect

    Chambers, D.B.; Lowe, L.M.; Stager, R.H.; Reilly, P.M.; Duport, P.

    1992-12-31

    Estimates of lung-cancer risk from exposure to radon daughters are largely based on epidemiological studies of underground miners. The reliability of exposure data for these miners is a cause for concern, as actual workplace measurements of radon and/or radon-daughter levels are either sparse or absent for the early years of mining, when much of the exposure occurred.

  11. An improved electrostatic integrating radon monitor with the CR-39 as alpha-particle detector.

    PubMed

    Fan, D; Zhuo, W; Chen, B; Zhao, C; Yi, Y; Zhang, Y

    2015-11-01

    In this study, based on the electrostatic integrating radon monitor (EIRM) developed by Iida et al., a new type of EIRM with the allyl glycol carbonate (CR-39) as alpha-particle detector was developed for outdoor radon measurements. Besides using the CR-39 to replace the cellulose nitrate film as alpha-particle detector, the electrode and the setting place of the CR-39 were also optimally designed based on the simulation results of the electric field and the detection efficiency. The calibration factor of the new EIRM was estimated to be 0.136±0.002 tracks cm(-2) (Bq m(-3) h)(-1), with the lower detection limit of 0.6 Bq m(-3) for a 2-month exposure. Furthermore, both the battery and the dry agent were also replaced to protect the environment. The results of intercomparison and field experiments showed that the performances of the new EIRM were much better than the original one. It suggests that the new type of ERIM is more suitable for large-scale and long-term outdoor radon surveys.

  12. Development and characterisation of a silicon PIN diode array based highly sensitive portable continuous radon monitor.

    PubMed

    Ashokkumar, P; Sahoo, B K; Raman, Anand; Mayya, Y S

    2014-03-01

    This paper discusses the development and characterisation of a portable and highly sensitive continuous radon monitor (CRM) based on an array of in-house developed silicon PIN diode detectors. The development of this system was initiated in view of the limitations of the available similar radon measurement systems with regards to low sensitivity. The system utilises a hemispherical metal chamber (1 L capacity) for active air sampling. A quantitative estimation of radon concentration is carried out through alpha spectroscopy of electro-deposited (222)Rn decay products on the detector surface. The system was successfully tested and characterised in laboratory conditions. The characterisation experiments included optimisation of sensitivity, calibration with respect to linearity and a study of the influence of humidity on its performance. The novel PIN diode array design yields a high sensitivity of 1.76 ± 0.003 counts h(-1)/(Bq m(-3)) at a relative humidity level of 10% in the sampled air, which is more than two times as high as that reported for similar commercial systems. This instrument displayed a minimum detectable activity level of 0.80 Bq m(-3). PMID:24334292

  13. Continuous and passive environmental radon monitoring: Measuring methods and health effects. (Latest citations from the INSPEC database). Published Search

    SciTech Connect

    1996-05-01

    The bibliography contains citations concerning continuous and passive radon (Rn) monitoring, measurement methods and equipment, and health effects from Rn concentration in air, water, and soils. Citations discuss the design, development, and evaluation of monitoring and detection devices, including alpha spectroscopy and dosimetry, track detecting and scintillation, thermoluminescent, electret, and electrode collection. Sources of Rn concentration levels found in building materials, ventilation systems, soils, and ground water are examined. Lung cancer-associated risks from Rn radiation exposure are explored. Radon monitoring in mining operations is excluded. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  14. Evaluation of radon emissions and potential control requirements

    SciTech Connect

    Not Available

    1989-08-01

    This report provides estimates of radon release rates at the Weldon Spring Quarry (WSQ) for existing conditions and conditions which are expected to exist as the bulk waste is excavated. It also estimates radon release rates for the Temporary Storage Area (TSA). In 1989, Rn-222 concentrations at the fence line exceeded DOE guidelines. Data on working level concentrations at one monitoring station indicate an effective whole body dose rate of 0.75 mrem/hr for radon daughters and 0.74 mrem/hr for thoron daughters at one meter above the quarry waste. Since some of the calculations are based on assumptions, they show only the relative difference in radon release between present conditions and either of two excavation scenarios. They can be used in calculations of public exposure and potential health effects to evaluate the relative merits of each excavation scenario in comparison with present release conditions. The model used to make the estimates in this report is useful for estimating the radon release rate for the entire period of excavation, but it is not suitable for estimating worker exposure over short periods of time. Therefore, worker exposure and appropriate requirements for personal protective equipment will be determined as the excavation proceeds. 19 refs., 13 tabs.

  15. Radon monitoring in groundwater samples from some areas of northern Rajasthan, India, using a RAD7 detector.

    PubMed

    Rani, Asha; Mehra, Rohit; Duggal, Vikas

    2013-01-01

    Radon monitoring has been increasingly conducted worldwide because of the hazardous effects of radon on the health of human beings. In the present research, groundwater samples were taken from hand pumps at different areas of the districts of SriGanganagar, Hanumangarh, Sikar and Churu in northern Rajasthan. RAD7, an electronic radon detector (Durridge co., USA), was used to estimate the radon concentration in groundwater used for drinking. Radon concentration in the groundwater ranged from 0.5 ± 0.3 Bq l(-1) (Chimanpura) to 85.7±4.9 Bq l(-1)(Khandela) with an average value of 9.03±1.03 Bq l(-1). In 89 % of the samples, radon concentration is well below the allowed maximum contamination level (MCL) of radon concentration in water of 11 Bq l(-1), proposed by US Environmental Protection Agency (USEPA). Only in 11 % of the samples, the recorded values were found to be higher than MCL proposed by USEPA and only in 5 % of the samples, the recorded values were found to be higher than the values between 4 and 40 Bq l(-1) suggested for radon concentration in water for human consumption by the United Nations Scientific Committee on the effect of Atomic Radiation (UNSCEAR). The annual effective dose in stomach and lungs per person was also evaluated in this research. The estimated total annual effective dose of adults ranged from 1.34 to 229.68 µSv y(-1). The total annual effective dose from three locations of the studied area was found to be greater than the safe limit (0.1 mSv y(-1)) recommended by World Health Organization and EU Council.

  16. Electronic radon monitoring with the CMOS System-on-Chip AlphaRad

    NASA Astrophysics Data System (ADS)

    Higueret, S.; Husson, D.; Le, T. D.; Nourreddine, A.; Michielsen, N.

    2008-01-01

    The development of the integrated circuit AlphaRad as a new System-on-Chip for detection of α-particles has already been reported. This paper deals with electronic monitoring of atmospheric radon, which is one of the promising applications of the chip. The future electronic radon monitor (ERM) is designed to be compact, inexpensive, operating at low voltage and fully stand-alone. We present here the complete electronic board of the future ERM: it is made of three independent AlphaRad chips running in parallel, mounted on a small printed-circuit board which includes a numeric block for data treatment based on a Xilinx programmable gate array. The maximal counting rate of the AlphaRad chip has been pushed to at least 3×10 6 α-particles cm -2. The complete system for detection of the solid aerosols will be published separately, and this paper will focus on the electronic board alone. Already 20 times faster than our first measurement with a CMOS pixel sensor, the system was tested at low and high activities, showing an excellent linearity for 222Rn levels up to 80 kBq m -3.

  17. Factors Affecting Radon Concentration in Houses

    NASA Astrophysics Data System (ADS)

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

    2001-03-01

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

  18. 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.

  19. Radon progeny monitoring at the Eastern North Atlantic (ENA), Graciosa Island ARM facility and a potential earthquake precursory signal

    NASA Astrophysics Data System (ADS)

    Barbosa, Susana; Mendes, Virgilio B.; Azevedo, Eduardo B.

    2016-04-01

    Radon has been considered a promising earthquake precursor, the main rationale being an expected increase in radon exhalation in soil and rocks due to stress associated with the preparatory stages of an earthquake. However, the precursory nature of radon is far from being convincingly demonstrated so far. A major hindrance is the many meteorological and geophysical factors diving radon temporal variability, including the geophysical parameters influencing its emanation (grain size, moisture content, temperature), as well as the meteorological factors (atmospheric pressure, moisture, temperature, winds) influencing its mobility. Despite the challenges, radon remains one of the strongest candidates as a potential earthquake precursor, and it is of crucial importance to investigate the many factors driving its variability and its potential association with seismic events. Continuous monitoring of radon progeny is performed at the Eastern North Atlantic (ENA) facility located in the Graciosa island (Azores, 39N; 28W), a fixed site of the Atmospheric Radiation Measurement programme (ARM), established and supported by the Department of Energy (DOE) of the United States of America with the collaboration of the local government and University of the Azores. The Azores archipelago is associated with a complex geodynamic setting on the Azores triple junction where the American, Eurasian and African litospheric plates meet, resulting in significant seismic and volcanic activity. A considerable advantage of the monitoring site is the availability of a comprehensive dataset of concurrent meteorological observations performed at the ENA facility and freely available from the ARM data archive, enabling a detailed analysis of the environmental factors influencing the temporal variability of radon's progeny. Gamma radiation is being measured continuously every 15 minutes since May 2015. The time series of gamma radiation counts is dominated by sharp peaks lasting a few hours and

  20. 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

  1. Invited Article: In situ comparison of passive radon-thoron discriminative monitors at subsurface workplaces in Hungary

    NASA Astrophysics Data System (ADS)

    Kávási, Norbert; Vigh, Tamás; Németh, Csaba; Ishikawa, Tetsuo; Omori, Yasutaka; Janik, Miroslaw; Yonehara, Hidenori

    2014-02-01

    During a one-year long measurement period, radon and thoron data obtained by two different passive radon-thoron discriminative monitors were compared at subsurface workplaces in Hungary, such as mines (bauxite and manganese ore) and caves (medical and touristic). These workplaces have special environmental conditions, such as, stable and high relative humidity (100%), relatively stable temperature (12°C-21°C), low or high wind speed (max. 2.4 m s-1) and low or elevated aerosol concentration (130-60 000 particles m-3). The measured radon and thoron concentrations fluctuated in a wide range among the different workplaces. The respective annual average radon concentrations and their standard deviations (in brackets) measured by the passive radon-thoron discriminative monitor with cellulose filter (CF) and the passive radon-thoron discriminative monitor with sponge filter (SF) were: 350(321) Bq m-3 and 550(497) Bq m-3 in the bauxite mine; 887(604) Bq m-3 and 1258(788) Bq m-3 in the manganese ore mine; 2510(2341) Bq m-3 and 3403(3075) Bq m-3 in the medical cave (Hospital Cave of Tapolca); and 6239(2057) Bq m-3 and 8512(1955) Bq m-3 in the touristic cave (Lake Cave of Tapolca). The respective average thoron concentrations and their standard deviation (in brackets) measured by CF and SF monitors were: 154(210) Bq m-3 and 161(148) Bq m-3 in the bauxite mine; 187(191) Bq m-3 and 117(147) Bq m-3 in the manganese-ore mine; 360(524) Bq m-3 and 371(789) Bq m-3 in the medical cave (Hospital Cave of Tapolca); and 1420(1184) Bq m-3 and 1462(3655) Bq m-3 in the touristic cave (Lake Cave of Tapolca). Under these circumstances, comparison of the radon data for the SF and CF monitors showed the former were consistently 51% higher in the bauxite mine, 38% higher in the manganese ore mine, and 34% higher in the caves. Consequently, correction is required on previously obtained radon data acquired by CF monitors at subsurface workplaces to gain comparable data for SF monitors. In the

  2. Invited Article: In situ comparison of passive radon-thoron discriminative monitors at subsurface workplaces in Hungary

    SciTech Connect

    Kávási, Norbert; Vigh, Tamás; Németh, Csaba; Ishikawa, Tetsuo; Omori, Yasutaka; Janik, Miroslaw; Yonehara, Hidenori

    2014-02-15

    During a one-year long measurement period, radon and thoron data obtained by two different passive radon-thoron discriminative monitors were compared at subsurface workplaces in Hungary, such as mines (bauxite and manganese ore) and caves (medical and touristic). These workplaces have special environmental conditions, such as, stable and high relative humidity (100%), relatively stable temperature (12°C–21°C), low or high wind speed (max. 2.4 m s{sup −1}) and low or elevated aerosol concentration (130–60 000 particles m{sup −3}). The measured radon and thoron concentrations fluctuated in a wide range among the different workplaces. The respective annual average radon concentrations and their standard deviations (in brackets) measured by the passive radon-thoron discriminative monitor with cellulose filter (CF) and the passive radon-thoron discriminative monitor with sponge filter (SF) were: 350(321) Bq m{sup −3} and 550(497) Bq m{sup −3} in the bauxite mine; 887(604) Bq m{sup −3} and 1258(788) Bq m{sup −3} in the manganese ore mine; 2510(2341) Bq m{sup −3} and 3403(3075) Bq m{sup −3} in the medical cave (Hospital Cave of Tapolca); and 6239(2057) Bq m{sup −3} and 8512(1955) Bq m{sup −3} in the touristic cave (Lake Cave of Tapolca). The respective average thoron concentrations and their standard deviation (in brackets) measured by CF and SF monitors were: 154(210) Bq m{sup −3} and 161(148) Bq m{sup −3} in the bauxite mine; 187(191) Bq m{sup −3} and 117(147) Bq m{sup −3} in the manganese-ore mine; 360(524) Bq m{sup −3} and 371(789) Bq m{sup −3} in the medical cave (Hospital Cave of Tapolca); and 1420(1184) Bq m{sup −3} and 1462(3655) Bq m{sup −3} in the touristic cave (Lake Cave of Tapolca). Under these circumstances, comparison of the radon data for the SF and CF monitors showed the former were consistently 51% higher in the bauxite mine, 38% higher in the manganese ore mine, and 34% higher in the caves

  3. Indoor Radon Measurement in Van

    NASA Astrophysics Data System (ADS)

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

    2007-04-01

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

  4. 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.

  5. Radon Diffusion Measurement in Polyethylene based on Alpha Detection

    SciTech Connect

    Rau, Wolfgang

    2011-04-27

    We present a method to measure the diffusion of Radon in solid materials based on the alpha decay of the radon daughter products. In contrast to usual diffusion measurements which detect the radon that penetrates a thin barrier, we let the radon diffuse into the material and then measure the alpha decays of the radon daughter products in the material. We applied this method to regular and ultra high molecular weight poly ethylene and find diffusion lengths of order of mm as expected. However, the preliminary analysis shows significant differences between two different approaches we have chosen. These differences may be explained by the different experimental conditions.

  6. Radon in soil gas--exhalation tests and in situ measurements.

    PubMed

    Lindmark, A; Rosen, B

    1985-10-01

    Radon in soil can move into buildings resulting in high radon daughter concentrations. The foundation of a dwelling should be adapted to the radon "risk" which is determined by the radon concentration and the air permeability of the soil. Different measuring procedures are discussed in this paper, both in situ measurements of radon content and laboratory tests on radon exhalation from different types of soils at different water contents. PMID:4081740

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

    SciTech Connect

    Brian M. Davis; Lewis Semprini; Jonathan Istok

    2003-02-27

    Naturally occurring 222-radon in ground water can potentially be used as an in situ partitioning tracer to characterize dense nonaqueous phase liquid (DNAPL) saturations. The static method involves comparing radon concentrations in water samples from DNAPL-contaminated and non-contaminated portions of an aquifer. During a push-pull test, a known volume of test solution (radon-free water containing a conservation tracer) is first injected (''pushed'') into a well; flow is then reversed and the test solution/groundwater mixture is extracted (''pulled'') from the same well. In the presence of NAPL radon transport is retarded relative to the conservative tracer. Assuming linear equilibrium partitioning, retardation factors for radon can be used to estimate NAPL saturations.The utility of this methodology was evaluated in laboratory and field settings.

  8. Radon in Irish Show Caves - Personal Monitoring Data From 2001-2006

    SciTech Connect

    Currivan, L.; Murray, M.; O'Colmain, M.; Pollard, D.

    2008-08-07

    The European Directive 96/29/EURATOM and its transposition into national legislation demands the application of radiation protection measures if the presence of radon and radon decay products leads to significant increase in exposures of workers. Irish legislation further demands that laboratories carrying out radon measurements operate a high level quality assurance programme. As a result of a reconnaissance survey regular measurements of show cave guides have been made in order to assess exposure to radon in such workplaces and to ascertain that the limits set for radon are not exceeded. In 2000, an action level of 400 Bqm{sup -3}, was established. Doses in the range 0.3-12.0 mSv have been estimated for workers for the period 2001-2006.

  9. Radon in Irish Show Caves—Personal Monitoring Data From 2001-2006

    NASA Astrophysics Data System (ADS)

    Currivan, L.; Murray, M.; O'Colmain, M.; Pollard, D.

    2008-08-01

    The European Directive 96/29/EURATOM and its transposition into national legislation demands the application of radiation protection measures if the presence of radon and radon decay products leads to significant increase in exposures of workers. Irish legislation further demands that laboratories carrying out radon measurements operate a high level quality assurance programme. As a result of a reconnaissance survey regular measurements of show cave guides have been made in order to assess exposure to radon in such workplaces and to ascertain that the limits set for radon are not exceeded. In 2000, an action level of 400 Bqm-3, was established. Doses in the range 0.3-12.0 mSv have been estimated for workers for the period 2001-2006.

  10. Epidemiological implications of spatial and temporal radon variations

    SciTech Connect

    Steck, D.J.; Lively, R.S.; Ney, E.P.

    1992-12-31

    Epidemiological studies require accurate assessments of total radon-daughter exposures. Short-term radon measurements taken in current dwellings may misrepresent past exposures. In the upper midwest, we have observed significant spatial variation, on a scale of several kilometers, in yearly average indoor radon concentrations. Thus, ecological studies using small samples, or case-control studies using only the current residences for exposure assessment, could misjudge the actual long-term exposures if the size of the geographical cluster used is larger than a county. Short-term measurements also may introduce unacceptable variation. In a comparison of two measurement techniques in 80 upper-midwest homes, a correlation was found between year-long alpha-track and 2-day charcoal canister measurements. However, the observed coefficient of variation (factor of two) between measurement protocols may introduce enough scatter to obscure weak correlations in small samples. A correlation that was observed between lung-cancer rates in 13 rural Minnesota counties and the annual-average radon concentration (median = 100 Bq m{sup {minus}3}) estimated from year-long alpha-track measurements was not found when charcoal canister data were used to estimate the radon exposure. Year-to-year variations may also be important. In 12 homes that have been monitored for longer than 1 y, yearly variations ranged from 0 to 500%, with a median variation of 22%. We are investigating a retrospective detection technique that may improve long-term radon exposure assessments. We have found correlation between the surface alpha activity and radon exposure for glass surfaces exposed from 6 to 2000 kBq y m{sup {minus}3}. We have developed an alpha-track detection system that measures both current radon concentrations and exposure history.

  11. 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. PMID:26599146

  12. 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+.

  13. 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+.

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

    PubMed

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

    2016-08-15

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

  15. Real-time setup to record radon emission during rock deformation: implications for geochemical surveillance

    NASA Astrophysics Data System (ADS)

    Tuccimei, P.; Mollo, S.; Soligo, M.; Scarlato, P.; Castelluccio, M.

    2015-02-01

    Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analyzing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress-strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A re-circulating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collision of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into an uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows to obtain a variety of stress-strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  16. Real-time setup to measure radon emission during rock deformation: implications for geochemical surveillance

    NASA Astrophysics Data System (ADS)

    Tuccimei, P.; Mollo, S.; Soligo, M.; Scarlato, P.; Castelluccio, M.

    2015-05-01

    Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analysing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress-strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A recirculating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collisions of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into a uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows obtaining a variety of stress-strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  17. Analysis of outdoor radon progeny concentration measured at the Spanish radioactive aerosol automatic monitoring network.

    PubMed

    Arnold, D; Vargas, A; Ortega, X

    2009-05-01

    An analysis of 10-year radon progeny data, provided by the Spanish automatic radiological surveillance network, in relation to meteorology is presented. Results show great spatial variability depending mainly on the station location and thus, the surrounding radon exhalation rate. Hourly averages show the typical diurnal cycle with an early morning maximum and a minimum at noon, except for one mountain station, which shows an inverse behaviour. Monthly averaged values show lower concentrations during months with higher atmospheric instability.

  18. High radon levels in subterranean environments: monitoring and technical criteria to ensure human safety (case of Castañar cave, Spain).

    PubMed

    Alvarez-Gallego, Miriam; Garcia-Anton, Elena; Fernandez-Cortes, Angel; Cuezva, Soledad; Sanchez-Moral, Sergio

    2015-07-01

    Castañar cave contains the highest radon gas ((222)Rn) concentration in Spain with an annual average of 31.9 kBq m(-)(3). Seasonal variations with summer minimums and maximum values in fall were recorded. The reduction of air-filled porosity of soil and rock by condensation or rainfalls hides the radon exchange by gas diffusion, determining this seasonal stair-step pattern of the radon activity concentration in underground air. The effective total dose and the maximum hours permitted have been evaluated for the guides and public safety with a highly detailed radon measurement along 2011 and 2012. A network of 12 passive detectors (kodalphas) has been installed, as well as, two radon continuous monitoring in the most interesting geological sites of the subterranean environment. A follow up of the recommended time (max. 50 min) inside the underground environment has been analysed since the reopen to public visitors for not surpassing the legal maximum effective dose for tourists and guides. Results shown that public visitors would receive in fall a 12.1% of the total effective dose permitted per visit, whereas in summer it is reduced to 8.6%, while the cave guide received a total effective dose of 6.41 mSv in four months. The spatial radon maps allow defining the most suitable touristic paths according to the radon concentration distribution and therefore, appropriate fall and summer touristic paths are recommended.

  19. High radon levels in subterranean environments: monitoring and technical criteria to ensure human safety (case of Castañar cave, Spain).

    PubMed

    Alvarez-Gallego, Miriam; Garcia-Anton, Elena; Fernandez-Cortes, Angel; Cuezva, Soledad; Sanchez-Moral, Sergio

    2015-07-01

    Castañar cave contains the highest radon gas ((222)Rn) concentration in Spain with an annual average of 31.9 kBq m(-)(3). Seasonal variations with summer minimums and maximum values in fall were recorded. The reduction of air-filled porosity of soil and rock by condensation or rainfalls hides the radon exchange by gas diffusion, determining this seasonal stair-step pattern of the radon activity concentration in underground air. The effective total dose and the maximum hours permitted have been evaluated for the guides and public safety with a highly detailed radon measurement along 2011 and 2012. A network of 12 passive detectors (kodalphas) has been installed, as well as, two radon continuous monitoring in the most interesting geological sites of the subterranean environment. A follow up of the recommended time (max. 50 min) inside the underground environment has been analysed since the reopen to public visitors for not surpassing the legal maximum effective dose for tourists and guides. Results shown that public visitors would receive in fall a 12.1% of the total effective dose permitted per visit, whereas in summer it is reduced to 8.6%, while the cave guide received a total effective dose of 6.41 mSv in four months. The spatial radon maps allow defining the most suitable touristic paths according to the radon concentration distribution and therefore, appropriate fall and summer touristic paths are recommended. PMID:25863322

  20. 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.

  1. Continuous and passive environmental radon monitoring: Measuring methods and health effects. (Latest citations from the INSPEC: Information services for the Physics and Engineering Communities database). Published Search

    SciTech Connect

    1993-08-01

    The bibliography contains citations concerning continuous and passive radon (Rn) monitoring, measurement methods and equipment, and health effects from Rn concentration in air, water, and soils. Citations discuss the design, development, and evaluation of monitoring and detection devices, including alpha spectroscopy and dosimetry, track detecting and scintillation, thermoluminescent, electret, and electrode collection. Sources of Rn concentration levels found in building materials, ventilation systems, soils, and ground water are examined. Lung cancer-associated risks from Rn radiation exposure are explored. Radon monitoring in mining operations is excluded. (Contains a minimum of 210 citations and includes a subject term index and title list.)

  2. Low Radon Cleanroom at the University of Alberta

    NASA Astrophysics Data System (ADS)

    Grant, Darren; Hallin, Aksel; Hanchurak, Stephen; Krauss, Carsten; Liu, Shengli; Soluk, Richard

    2011-04-01

    A cleanroom laboratory designed to create and maintain a low concentration of radon in the air has been designed and is now under construction. We describe the clean room, the radon stripping system, and various radon monitoring tools.

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

    SciTech Connect

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

    1996-06-01

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

  4. 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

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

    PubMed

    Hadad, Kamal; Doulatdar, R; Mehdizadeh, S

    2007-01-01

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

  6. Evaluation of radon progeny from Mount St. Helens eruptions. Final report

    SciTech Connect

    Lepel, E.A.; Olsen, K.B.; Thomas, V.W.; Eichner, F.N.

    1982-09-01

    A network of twelve monitoring sites around Mount St. Helens was established to evaluate possible short-lived radioactivity in the fallen ash. Seven sites were located near major population centers of Washington and Oregon, and five sites were located within 80 km of the volcano. Each site monitored the radioactivity present by the use of thermoluminescent dosimeters which recorded the total exposure to radioactivity over the exposure period. Eruptions occurring on July 22, August 7, and October 16 to 18, 1980 were monitored. No statistically significant quantities of measurable radon daughters were observed.

  7. 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.

  8. Active faults on the eastern flank of Etna volcano (Italy) monitored through soil radon measurements

    NASA Astrophysics Data System (ADS)

    Neri, M.; Giammanco, S.; Ferrera, E.; Patanè, G.; Zanon, V.

    2012-04-01

    This study concerns measurements of radon and thoron emissions from soil carried out in 2004 on the unstable eastern flank of Mt. Etna, in a zone characterized by the presence of numerous seismogenic and aseismic faults. The statistical treatment of the geochemical data allowed recognizing anomaly thresholds for both parameters and producing distribution maps that highlighted a significant spatial correlation between soil gas anomalies and tectonic lineaments. In particular, the highest anomalies were found at the intersection between WNW-ESE and NW-SE -running faults. The seismic activity occurring in and around the study area during 2004 was analyzed, producing maps of hypocentral depth and released seismic energy. These maps revealed a progressive deepening of hypocenters from NW to SE, with the exception of a narrow zone in the central part of the area, with a roughly WNW-ESE direction. Also, the highest values of seismic energy were released during events in the southern and northwestern sectors of the area. Both radon and thoron anomalies were located in areas affected by relatively deep (5-10 km depth) seismic activity, while less evident correlation was found between soil gas anomalies and the released seismic energy. This study confirms that mapping the distribution of radon and thoron in soil gas can reveal hidden faults buried by recent soil cover or faults that are not clearly visible at the surface. The correlation between soil gas data and earthquake depth and intensity can give some hints on the source of gas and/or on fault dynamics. Lastly, an important spin-off of this study is the recognition of some areas where radon activity was so high (>50000 Bq/m3) that it may represent a potential hazard to the local population. In fact, radon is the leading cause of lung cancer after cigarette smoke for long exposures and, due to its molecular weight, it accumulates in underground rooms or in low ground, particularly where air circulation is low or absent

  9. Raising Strong Daughters.

    ERIC Educational Resources Information Center

    Gadeberg, Jeanette

    In response to an alarming drop in girls' self-esteem in early adolescence, this parents' guide provides suggestions for raising daughters to become confident, healthy, and independent. Chapter 1, "Yesterday's Daughters," examines how cultural messages inhibit girls' development. Chapter 2, "Raising an Opinionated Daughter," suggests how to help…

  10. Deposition-based passive monitors for assigning radon, thoron inhalation doses for epidemiological studies.

    PubMed

    Mayya, Y S; Mishra, R; Prajith, R; Gole, A C; Sapra, B K; Chougaonkar, M P; Nair, R R K; Ramola, R C; Karunakara, N; Koya, P K M

    2012-11-01

    The International Commission on Radiological Protection dose limits for radiation protection have been based on linearly extrapolating the high-dose risk coefficients obtained from the Japanese A bomb survivor data to low doses. The validity of these extrapolations has been questioned from time to time. To overcome this, epidemiological studies have been undertaken across the world on populations chronically exposed to low-radiation levels. In the past decade, the results of these studies have yielded widely differing, and sometimes, contradictory, conclusions. While recent residential radon studies have shown statistically significant radon risks at low doses, high-level natural radiation (HLNR) studies in China and India have not shown any low-dose risks. Similar is the case of a congenital malformation study conducted among the HLNR area populations in Kerala, India. It is thus necessary to make efforts at overcoming the uncertainties in epidemiological studies. In the context of HLNR studies, assigning radon and thoron doses has largely been an area of considerable uncertainty. Conventionally, dosimetry is carried out using radon concentration measurements, and doses have been assigned using assumed equilibrium factors for the progeny species. Gas-based dose assignment is somewhat inadequate due to variations in equilibrium factors and possibly due to significant thoron. In this context, passive, deposition-based progeny dosimetry appears to be a promising alternative method to assess inhalation doses directly. It has been deployed in various parts of India, including HBRAs and countries in Europe. This presentation discusses the method, the results obtained and their relevance to dose assignment in Indian epidemiological studies.

  11. Contribution of waterborne radon to home air quality

    SciTech Connect

    Deb, A.K.

    1994-12-31

    Radon-222 is a member of the uranium decay chain and is formed from the decay of radium-226. Radon and its decay products emit alpha particles during the decay process. If radon is inhaled, alpha particles emitted from inhaled radon and its daughters increase the risk of lung cancer. Radon is soluble in water; thus when radon comes in contact with groundwater it dissolves. The radon concentration in groundwater may range from 100 pCi/L to 1,000,000 pCi/L. When water with a high radon level is used in the home, radon is released from the water to the air and thus can increase indoor air radon concentration. Considering the estimated health risk from radon in public water supply systems, EPA has proposed a maximum contaminant level (MCL) of 300 pCi/L for radon in public drinking water supplies. To address the health risks of radon in water and the proposed regulations, the American Water Works Association Research Foundation (AWWARF) initiated a study to determine the contribution of waterborne radon to radon levels in indoor household air.

  12. Effects of Radon Inhalation on Some Biophysical Properties of Blood in Rats

    NASA Astrophysics Data System (ADS)

    Essa, M. F.; Shahin, Fayez M.; Ahmed, Ashour M.; Abdel-Salam, Omar

    2013-03-01

    The major source of human exposure to natural radiation arises from the inhalation of radon (222Rn) gas. Exposure to high concentrations of radon 222Rn and its daughters for long period leads to pathological effects like lung cancer, leukaemia, skin cancer and kidney diseases. The present study was performed on rats to investigate the effect of radon exposure on the absorption spectra of hemoglobin. Measurements have been performed in a radon chamber where rats were exposed to radon for 1, 5 or 7 weeks. The inhalation of radon resulted in decrease in intensity of the absorption bands characterizing the hemoglobin molecular structure with increased radon doses.

  13. Radon detection and measurement. (Latest citations from the EI compendex*plus database). Published Search

    SciTech Connect

    1996-08-01

    The bibliography contains citations concerning the measurement of radon and radon daughter isotopes in various environments. Radon measurement in homes and buildings, mines, rainwater, groundwater, soils, the Arctic and other atmosphere, and exhaled air is discussed. Radon exhalation rates of building materials and mine tailings are noted. Analytical methods and equipment used to measure radon and radon isotopes are described. Radon detection as an earthquake prediction tool is briefly presented.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

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

    SciTech Connect

    Harley, N.H.

    1990-01-01

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

  15. Assessing the risks from exposure to radon in dwellings

    SciTech Connect

    Walsh, P.J.; Lowder, W.M.

    1983-07-01

    The factors used to assess the radiation dose and health risks from human exposure to radon in dwellings are critically reviewed in this summary. Sources of indoor radon and determinants of air concentrations and exposure levels are given as well as the uncertainties that exist in their formulation. Methods of assessing health effects from inhalation of radon and its progeny are discussed with emphasis on dosimetry of radon daughters and formulation of risk per dose values. Finally, methods of assessing risks for general population exposures to indoor radon concentrations are treated.

  16. Radon exchange dynamics in a karst system investigated by radon continuous measurements in water: first results.

    PubMed

    Peano, G; Vigna, B; Villavecchia, E; Agnesod, G

    2011-05-01

    In 2008 the underground Karst Laboratory of Bossea Cave started research on radon exchange dynamics between bedrock, cave waters (main collector and percolations) and indoor underground atmosphere. Radon air concentrations, normally high, increase more and more during the collector's floods. An explanation of this is a radon-water solubilisation process more effective in flood events, because of a greater rock-water contact surface. Radon is then carried by water into the cave and released into the air. To verify this, continuous measurements of radon concentration are needed not only in the air, but also in the waters of the cave. So a new device for continuous radon monitoring in water was tested, connected to the AlphaGuard radon monitor. For the first 6 months of 2010, for different sections of the cave, the correlations between radon in the air, radon in the waters and the collector's stream flow fluctuations were presented and discussed. PMID:21586541

  17. Additional contamination when radon is in excess.

    PubMed

    Martín Sánchez, A; de la Torre Pérez, J; Ruano Sánchez, A B; Naranjo Correa, F L

    2013-11-01

    A study of the behavior of the (222)Rn progeny on clothes, skin and hair has been performed in a place with very high radon concentration. In the past, radon concentration was established to be about 32 kBq/m(3) in a very high humidity environment inside a tourist cave in Extremadura (Spain). The results show that (222)Rn daughters are adhered on clothes, skin and hair, adding some radioactive concentration to that due to radon and its progeny existing in the breathable air. PMID:23548693

  18. Radon in atmospheric studies: a review

    SciTech Connect

    Wilkening, M.

    1981-01-01

    The distribution of the isotopes of radon in space and time, their physical characteristics, and their behavior in the dynamics of the atmosphere have presented challenges for many decades. /sup 220/Rn, /sup 222/Rn and their daughters furnish a unique set of tracers for the study of transport and mixing processes in the atmosphere. Appropriate applications of turbulent diffusion theory yield general agreement with measured profiles. Diurnal and seasonal variations follow patterns set by consideration of atmospheric stability. /sup 222/Rn has been used successfully in recent studies of nocturnal drainage winds and cumulus convection. Good results have been obtained using /sup 222/Rn and its long-lived /sup 210/Pb daughter as tracers in the study of continent-to-ocean and ocean-to-continent air mass trajectories, /sup 220/Rn (thoron) because of its short half-life of only 55 seconds has been used to measure turbulent diffusion within the first few meters of the earth's surface and to study the influence of meteorological variables on the rate of exhalation from the ground. Radon daughters attach readily to atmospheric particulate matter which makes it possible to study these aerosols with respect to size spectra, attachment characteristics, removal by gravitation and precipitation, and residence times in the troposphere. The importance of ionization by radon and its daughters in the lower atmosphere and its effect on atmospheric electrical parameters is well known. Knowledge of the mobility and other characteristics of radon daughter ions has led to applications in the study of atmospheric electrical environments under fair weather and thunderstorm conditions and in the formation of condensation nuclei. The availability of increasingly sophisticated analytical tools and atmospheric measurement systems can be expected to add much to our understanding of radon and its daughters as trace components of the atmospheric environment in the years ahead.

  19. Methodology issues in risk assessment for radon

    SciTech Connect

    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 US from indoor radon exposure. The accuracy of the estimated 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 US 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.

  20. Radon variations during treatment in thermal spas of Lesvos Island (Greece).

    PubMed

    Vogiannis, Efstratios; Nikolopoulos, Dimitrios; Louizi, Anna; Halvadakis, C P

    2004-01-01

    The aim of this paper was to study the variations of radon and daughter nuclei during treatment in the thermal spas of Lesvos Island (Greece). For this purpose, in the thermal spas of Lesvos we have measured the radon concentrations of thermal waters, as well as indoor radon, daughter and coarse particle (>500 nm) concentration. Various instruments and procedures were employed for measurements. Radon concentrations of thermal waters were found to lie in the range 10 and 304 Bq l(-1). Concentration peaks both for radon, radon daughter and coarse particle, were found to appear during filling of baths in the treatment process. The doses delivered to the bathers during treatment were in the range of 0.00670 mSv per year to 0.1279 mSv per year, while the doses delivered to personnel were below 20 mSv per year.

  1. Indoor radon

    SciTech Connect

    Rabkin, M.A.; Bodansky, D.

    1988-12-31

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

  2. TRAPPIST photometry and imaging monitoring of comet C/2013 R1 (Lovejoy): Implications for the origin of daughter species

    NASA Astrophysics Data System (ADS)

    Opitom, C.; Jehin, E.; Manfroid, J.; Hutsemékers, D.; Gillon, M.; Magain, P.

    2015-12-01

    We report the results of the narrow-band photometry and imaging monitoring of comet C/2013 R1 (Lovejoy) with the robotic telescope TRAPPIST (La Silla observatory). We gathered around 400 images over 8 months pre- and post-perihelion between September 12, 2013 and July 6, 2014. We followed the evolution of the OH, NH, CN, C3, and C2 production rates computed with the Haser model, as well as the evolution of the dust production. All five gas species display an asymmetry about perihelion, since the rate of brightening is steeper than the rate of fading. The study of the coma morphology reveals gas and dust jets that indicate one or several active zone(s) on the nucleus. The dust, C2, and C3 morphologies present some similarities, while the CN morphology is different. OH and NH are enhanced in the tail direction. The study of the evolution of the comet activity shows that the OH, NH, and C2 production rate evolution with the heliocentric distance is correlated to the dust evolution. The CN and, to a lesser extent, the C3 do not display such a correlation with the dust. This evidence and the comparison with parent species production rates indicate that C2 and C3, on one hand, and OH and NH, on the other, could be - at least partially - released from organic - rich grains and icy grains. On the contrary, all evidences point to HCN being the main parent of CN in this comet. Appendix A is available in electronic form at http://www.aanda.org

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

    SciTech Connect

    Muellerova, Monika; Holy, Karol

    2010-01-05

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

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

    NASA Astrophysics Data System (ADS)

    Müllerová, Monika; Holý, Karol

    2010-01-01

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

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

    PubMed

    Matiullah; Malik, Fariha; Rafique, Muhammad

    2012-12-01

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

  6. 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.

  7. 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)

  8. Soil radon ( 222 Rn) monitoring at Furnas Volcano (São Miguel, Azores): Applications and challenges

    NASA Astrophysics Data System (ADS)

    Silva, C.; Ferreira, T.; Viveiros, F.; Allard, P.

    2015-05-01

    A soil 222Rn continuous monitoring test was performed in three sampling points inside Furnas Volcano caldera and 222Rn concentration varied between 0 and 153000 Bq/m3. Multivariate regression and spectral analyses were applied to the time series registered in order to understand and filter the influence of external factors on soil 222Rn concentration and to recognise anomalies correlated with deep processes. The regression models show that barometric pressure, soil water content, soil temperature, soil CO2 flux, air temperature, relative air humidity and wind speed are the statistical meaningful variables explaining between 15.8% and 73.6% of 222Rn variations. Spectral analysis allowed to identify seasonal variations and daily variations associated with one cycle per day on winter months only in one of the monitored sites. This diurnal variation is correlated with air temperature, relative air humidity and wind speed cycles. The change in the location of the sampling points was caused by both artificial and natural constrains. On the three monitoring sites, after a period of continuous register, a sudden drop on the 222Rn concentration values was observed and the cause is still under debate. The work performed can be applied for seismovolcanic monitoring and for public health risk assessment.

  9. Novel approaches in radon and thoron dosimetry

    NASA Astrophysics Data System (ADS)

    Pressyanov, D.; Dimitrov, D.; Dimitrova, I.; Georgiev, S.; Mitev, K.

    2014-07-01

    This report presents some novel approaches for radon/radon progeny and thoron measurements that can help to resolve some long-lasting problems in dosimetry, but which are not yet part of the common practice. The focus is in two directions: The use of CDs/DVDs as radon and thoron detectors and the employment of grab-sampling and/or integrated radon progeny measurements for diagnostic of the air conditions related to mitigation and indoor ventilation. The potential of these approaches is illustrated by several successful applications: (1) Study of the 222Rn distribution in large buildings and identification of places with radon problem; (2) Radon and thoron monitoring in underground mines; (3) Radon measurements in natural waters, including directly in the water source; (4) Grab sampling 222Rn progeny measurements for the purposes of pre- and post-mitigation diagnostic; (5) Integrated measurements of individual 222Rn short-lived decay products for diagnostic of indoor ventilation conditions.

  10. 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.

  11. Radon discrimination for work place air samples

    SciTech Connect

    Bratvold, T.

    1994-09-27

    Gross alpha/beta measurement systems are designed solely to identify an incident particle as either an alpha or a beta and register a count accordingly. The tool of choice for radon identification, via decay daughters, is an instrument capable of identifying the energy of incident alpha particles and storing that information separately from detected alpha emissions of different energy. In simpler terms, the desired instrument is an alpha spectroscopy system. K Basins Radiological Control (KBRC) procured an EG&G ORTEC OCTETE PC alpha spectroscopy system to facilitate radon identification on work place air samples. The alpha spectrometer allows for the identification of any alpha emitting isotope based on characteristic alpha emission energies. With this new capability, KBRC will explicitly know whether or not there exists a true airborne concern. Based on historical air quality data, this new information venue will reduce the use of respirators substantially. Situations where an area remains ``on mask`` due solely to the presence of radon daughters on the grab air filter will finally be eliminated. This document serves to introduce a new method for radon daughter detection at the 183KE Health Physics Analytical Laboratory (HPAL). A new work place air sampling analysis program will be described throughout this paper. There is no new technology being introduced, nor any unproven analytical process. The program defined over the expanse of this document simply explains how K Basins Radiological Control will employ their alpha spectrometer.

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

    SciTech Connect

    Muellerova, M.; Holy, K.

    2007-11-26

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

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

    NASA Astrophysics Data System (ADS)

    Müllerová, M.; Holý, K.

    2007-11-01

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

  14. Differentiation between earthquake radon anomalies and those arising from nuclear activities.

    PubMed

    Elmaghraby, Elsayed K; Lotfy, Yahia A

    2009-01-01

    The present work offers a methodology to correlate the earthquake time, magnitude and location based on the behavior of radon concentration. By correlating tectonic events to radon behavior, based on previously published radon data, radon concentration signals can be taken into consideration in decision making. Three correlations between magnitude, time and epicenter distance are presented. The applicability of any one of them depends on the measurement technique. Moreover, a suggested procedure is presented to determine the possible confusion between signals for radon anomalies originating from tectonic failure and those arising from nuclear activities. The suggested method depends on the change observed on the (219)Rn and (222)Rn daughters concentration ratios.

  15. On the interaction between radon progeny and particles generated by electronic and traditional cigarettes

    NASA Astrophysics Data System (ADS)

    Vargas Trassierra, C.; Cardellini, F.; Buonanno, G.; De Felice, P.

    2015-04-01

    During their entire lives, people are exposed to the pollutants present in indoor air. Recently, Electronic Nicotine Delivery Systems, mainly known as electronic cigarettes, have been widely commercialized: they deliver particles into the lungs of the users but a "second-hand smoke" has yet to be associated to this indoor source. On the other hand, the naturally-occurring radioactive gas, i.e. radon, represents a significant risk for lung cancer, and the cumulative action of these two agents could be worse than the agents separately would. In order to deepen the interaction between radon progeny and second-hand aerosol from different types of cigarettes, a designed experimental study was carried out by generating aerosol from e-cigarette vaping as well as from second-hand traditional smoke inside a walk-in radon chamber at the National Institute of Ionizing Radiation Metrology (INMRI) of Italy. In this chamber, the radon present in air comes naturally from the floor and ambient conditions are controlled. To characterize the sidestream smoke emitted by cigarettes, condensation particle counters and scanning mobility particle sizer were used. Radon concentration in the air was measured through an Alphaguard ionization chamber, whereas the measurement of radon decay product in the air was performed with the Tracelab BWLM Plus-2S Radon daughter Monitor. It was found an increase of the Potential Alpha-Energy Concentration (PAEC) due to the radon decay products attached to aerosol for higher particle number concentrations. This varied from 7.47 ± 0.34 MeV L-1 to 12.6 ± 0.26 MeV L-1 (69%) for the e-cigarette. In the case of traditional cigarette and at the same radon concentration, the increase was from 14.1 ± 0.43 MeV L-1 to 18.6 ± 0.19 MeV L-1 (31%). The equilibrium factor increases, varying from 23.4% ± 1.11% to 29.5% ± 0.26% and from 30.9% ± 1.0% to 38.1 ± 0.88 for the e-cigarette and traditional cigarette, respectively. These growths still continue for long

  16. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon

    SciTech Connect

    Weinberg, C.R.

    1995-11-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of {alpha}-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining {alpha}-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting {open_quotes}measurement confounding{close_quotes} can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. 18 refs., 4 figs.

  17. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon.

    PubMed Central

    Weinberg, C R

    1995-01-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of alpha-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining alpha-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting "measurement confounding" can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. Images Figure 1. Figure 2. Figure 3. Figure 4. PMID:8605854

  18. The control of radon progeny by air treatment devices.

    PubMed

    Rajala, M; Janka, K; Lehtimäki, M; Kulmala, V; Graeffe, G; Keskinen, J

    1985-10-01

    The effect of air treatment devices on the behaviour of radon decay products has been studied in laboratory conditions. An HEPA filter and an electrostatic precipitator were used. Both of the filters were found to decrease the equilibrium factor of daughters and increase the unattached fraction of decay products. In a clean air they also decreased the activity of unattached daughters. The effect of the devices on the health risk caused by radon progeny was estimated by dosimetric calculations. The results corresponding to different models show considerable discrepancy, mainly due to different assumptions about the influence of unattached decay products on the dose.

  19. Room for a role for radon in lung cancer causation?

    PubMed

    Axelson, O

    1984-01-01

    Reduced ventilation due to energy saving has focussed interest on a potential lung cancer risk from increased indoor concentrations of alpha-emitting radon and radon daughters, escaping from building materials and from the ground. Some preliminary studies now also indicate a hazard to be present as related to radon daughter exposure in homes. However, the indoor radon daughter levels have probably been continuously increasing for half a century, especially in colder climates, due to the introduction of central heating instead of stoves and open fire places, reducing thermal ventilation. Furthermore, in our time, many people have got additional exposure through extended indoor work time instead of earlier outdoor activities in farming etc. The steeply increasing lung cancer rates over the past decades as well as the various oddities affecting the relationship between smoking and lung cancer, e.g. the urban-rural difference in lung cancer risk, also after standardization for smoking, the influence of immigration on lung cancer morbidity as well as the varying rates over the world and other observations, would obtain simple explanations by taking radon daughter exposure into account in addition to smoking. Then, also some curious and hitherto unexplained "inverse" relationships between lung cancer and inhalation of cigarette smoke or bronchitis in air-polluted areas, respectively, would become understandable.

  20. Your Daughter's First Gynecological Exam

    MedlinePlus

    ... issues to discuss. Stress to your daughter the importance of answering these questions truthfully, even though she might feel uncomfortable about it. For example, the health professional can help determine, based on your daughter's sexual ...

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

    SciTech Connect

    Samuelsson, C.

    1990-07-01

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

  2. Adsorption of radon and water vapor on commercial activated carbons

    SciTech Connect

    Hassan, N.M.; Ghosh, T.K.; Hines, A.L.; Loyalka, S.K.

    1995-02-01

    Equilibrium adsorption isotherms are reported for radon and water vapor on two commercial activated carbons: coconut shell Type PCB and hardwood Type BD. The isotherms of the water vapor were measured gravimetrically at 298 K. The isotherms of radon from dry nitrogen were obtained at 293, 298, and 308 K while the data for the mixture of radon and water vapor were measured at 298 K. The concentrations of radon in the gas and solid phases were measured simultaneously, once the adsorption equilibrium and the radioactive equilibrium between the radon and its daughter products were established. The shape of the isotherms was of Type III for the radon and Type V for the water vapor, according to Brunauer`s classification. The adsorption mechanism was similar for both the radon and the water vapor, being physical adsorption on the macropore surface area in the low pressure region and micropore filling near saturation pressure. The uptake capacity of radon decreased both with increasing temperature and relative humidity. The heat of adsorption data indicated that the PCB- and the BD-activated carbons provided a heterogeneous surface for radon adsorption. The equilibrium data for radon were correlated with a modified Freundlich equation.

  3. A passive radon dosemeter suitable for workplaces.

    PubMed

    Orlando, C; Orland, P; Patrizii, L; Tommasino, L; Tonnarini, S; Trevisi, R; Viola, P

    2002-01-01

    The results obtained in different international intercomparisons on passive radon monitors have been analysed with the aim of identifying a suitable radon monitoring device for workplaces. From this analysis, the passive radon device, first developed for personal dosimetry in mines by the National Radiation Protection Board, UK (NRPB), has shown the most suitable set of characteristics. This radon monitor consists of a diffusion chamber, made of conductive plastic with less than 2 cm height, containing a CR-39 film (Columbia Resin 1939), as track detector. Radon detectors in workplaces may be exposed only during the working hours, thus requiring the storage of the detectors in low-radon zones when not exposed. This paper describes how this problem can be solved. Since track detectors are also efficient neutron dosemeters, care should be taken when radon monitors are used in workplaces, where they may he exposed to neutrons, such as on high altitude mountains, in the surroundings of high energy X ray facilities (where neutrons are produced by (gamma, n) reactions) or around high energy particle accelerators. To this end, the response of these passive radon monitors to high energy neutron fields has been investigated. PMID:12408493

  4. 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.

  5. 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.

  6. 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.

  7. The effects of environmental parameters on diffuse degassing at Stromboli volcano: Insights from joint monitoring of soil CO2 flux and radon activity

    NASA Astrophysics Data System (ADS)

    Laiolo, M.; Ranaldi, M.; Tarchini, L.; Carapezza, M. L.; Coppola, D.; Ricci, T.; Cigolini, C.

    2016-04-01

    Soil CO2 flux and 222Rn activity measurements may positively contribute to the geochemical monitoring of active volcanoes. The influence of several environmental parameters on the gas signals has been substantially demonstrated. Therefore, the implementation of tools capable of removing (or minimising) the contribution of the atmospheric effects from the acquired time series is a challenge in volcano surveillance. Here, we present 4 years-long continuous monitoring (from April 2007 to September 2011) of radon activity and soil CO2 flux collected on the NE flank of Stromboli volcano. Both gases record higher emissions during fall-winter (up to 2700 Bq * m- 3 for radon and 750 g m- 2 day- 1 for CO2) than during spring-summer seasons. Short-time variations on 222Rn activity are modulated by changes in soil humidity (rainfall), and changes in soil CO2 flux that may be ascribed to variations in wind speed and direction. The spectral analyses reveal diurnal and semi-diurnal cycles on both gases, outlining that atmospheric variations are capable to modify the gas release rate from the soil. The long-term soil CO2 flux shows a slow decreasing trend, not visible in 222Rn activity, suggesting a possible difference in the source depth of the of the gases, CO2 being deeper and likely related to degassing at depth of the magma batch involved in the February-April 2007 effusive eruption. To minimise the effect of the environmental parameters on the 222Rn concentrations and soil CO2 fluxes, two different statistical treatments were applied: the Multiple Linear Regression (MLR) and the Principal Component Regression (PCR). These approaches allow to quantify the weight of each environmental factor on the two gas species and show a strong influence of some parameters on the gas transfer processes through soils. The residual values of radon and CO2 flux, i.e. the values obtained after correction for the environmental influence, were then compared with the eruptive episodes that

  8. 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.

  9. 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

  10. 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)

  11. Studies on the reduction of radon plate-out

    SciTech Connect

    Bruemmer, M.; Nakib, M.; Calkins, R.; Cooley, J. Sekula, S.

    2015-08-17

    The decay of common radioactive gases, such as radon, produces stable isotopes by a sequence of daughter particles with varied half-lives. These daughter particles are a significant source of gamma, neutron, and alpha (α) particle backgrounds that can mimic desired signals in dark matter and neutrinoless double beta decay experiments. In the LUMINA Laboratory at Southern Methodist University (SMU), studies of radon plate-out onto copper samples are conducted using one of XIA’s first five UltraLo 1800 alpha counters. We present results from investigations into various mitigation approaches. A custom-built copper holder (in either plastic or metal) has been designed and produced to maximize the copper’s exposure to {sup 220}Rn. The {sup 220}Rn source is a collection of camping lantern mantles. We present the current status of control and experimental methods for addressing radon exposure levels.

  12. Studies on the reduction of radon plate-out

    NASA Astrophysics Data System (ADS)

    Bruemmer, M.; Nakib, M.; Calkins, R.; Cooley, J.; Sekula, S.

    2015-08-01

    The decay of common radioactive gases, such as radon, produces stable isotopes by a sequence of daughter particles with varied half-lives. These daughter particles are a significant source of gamma, neutron, and alpha (α) particle backgrounds that can mimic desired signals in dark matter and neutrinoless double beta decay experiments. In the LUMINA Laboratory at Southern Methodist University (SMU), studies of radon plate-out onto copper samples are conducted using one of XIA's first five UltraLo 1800 alpha counters. We present results from investigations into various mitigation approaches. A custom-built copper holder (in either plastic or metal) has been designed and produced to maximize the copper's exposure to 220Rn. The 220Rn source is a collection of camping lantern mantles. We present the current status of control and experimental methods for addressing radon exposure levels.

  13. Internal emitter limits for iodine, radium and radon daughters

    SciTech Connect

    Schlenker, R.A.

    1984-08-15

    This paper identifies some of the issues which arise in the consideration of the derivation of new limits on exposure to internal emitters. Basic and secondary radiation protection limits are discussed. Terms are defined and applied to the limitation of risk from stochastic effects. Non-stochastic data for specific internal emitters (/sup 131/I and the radium isotopes) are presented. Emphasis is placed on the quantitative aspects of the limit setting problem. 65 references, 2 figures, 12 tables.

  14. Radon Update: Facts concerning environmental radon: Levels, mitigation strategies, dosimetry, effects and guidelines

    SciTech Connect

    Brill, A.B.; Becker, D.V.; Donahoe, K.

    1994-02-01

    The risk from environmental radon levels is not higher now than in the past, when residential exposures were not considered to be a significant health hazard. The majority of the radon dose is not from radon itself, but from short-lived alpha-emitting radon daughters, most notably {sup 218}Po (T{sub {1/2}}3min) and {sup 214}Po(T{sub {1/2}}19.7 min). Radon gas can penetrate homes from many sources and in various fashions. Measuring radon in homes is simple and relatively inexpensive and may be accomplished in a variety of ways. Although it is not possible to radon-proof a house, it is possible to reduce the level. In high radon areas, if the average level is higher than 4-8 pCi/liter (NCRP recommended level is 8 pCi/liter; EPA recommmended level is 4 PCi/liter), appropriate action is advised. The shape of the dose response curves for miners exposed to alpha-emitting particles in the workplace is consistent with current biologic knowledge. It is linear in the low dose range and saturates in the high dose range. No detectable increase in lung cancer frequency is seen in the lowest exposed miners (those with exposures <120 WLM, the relevant dose interval for most homes). Evidence for a health effect from radon exposure is based on data from animal studies and epidemiologic studies of mines. Extensive radiobiologic data predict a linear dose-response curve in the low dose region due to poor biological repair mechanisms for the high density of ionizing events that alpha particles create. However, no compelling evidence for increased cancer risks has yet been demonstrated from {open_quotes}acceptable{close_quotes}levels (<4-8 pCi/liter). 58 refs., 11 figs., 12 tabs.

  15. Characterisation of an electronic radon gas personal dosemeter.

    PubMed

    Gründel, M; Postendörfer, J

    2003-01-01

    The monitoring of radon exposure at workplaces is of great importance. Up to now passive measurement systems have been used for the registration of radon gas. Recently an electronic radon gas personal dosemeter came onto the market as an active measurement system for the registration of radon exposure (DOSEman; Sarad GmbH, Dresden, Germany). In this personal monitor, the radon gas diffuses through a membrane into a measurement chamber. A silicon detector system records spectroscopically the alpha decays of the radon gas and of the short-lived progeny 218Po and 214Po gathered onto the detector by an electrical field. In this work the calibration was tested and a proficiency test of this equipment was made. The diffusion behaviour of the radon gas into the measurement chamber, susceptibility to thoron, efficiency, influence of humidity, accuracy and the detection limit were checked. PMID:14756187

  16. Characterisation and monitoring of the Excavation Disturbed Zone (EDZ) in fractured gneisses of the Roselend underground laboratory: permeability measurements, transport property changes and related radon bursts

    NASA Astrophysics Data System (ADS)

    Wassermann, Jérôme; Sabroux, Jean-Christophe; Richon, Patrick; Pontreau, Sébastien; Guillon, Sophie; Pili, Eric

    2010-05-01

    pressure measurements between an obturated borehole and the tunnel is conducted to monitor the possible modifications of the transport properties of the EDZ due to hydraulical and/or mechanical sollicitations of the nearby Roselend reservoir lake. As radon level is controlled by emanation and transport path through the medium. The observed bursts of radon should be due to changes of the radon transport properties (Trique et al. 1999) of the EDZ. A correlation between the differential pressure variations and radon bursts is clearly observed. Radon bursts seem to be related to overpressure events that take place in the instrumented borehole. Which external sollicitations, hydraulical or mechanical, or both, induce such a behaviour? References Bossart, P., Meier, P. M., Moeri, A., Trick, T., and J.-C. Mayor (2002). Geological and hydraulic characterisation of the excavation disturbed zone in the Opalinus Clay of the Mont Terri Rock Laboratory, Engineering Geology, 66, 19-38. Dezayes, C., and T. Villemin (2002). Etat de la fracturation dans la galerie CEA de Roselend et analyse de la déformation cassante dans le massif du Méraillet, technical report, Lab. de Geodyn. de Chaisnes Alp., Univ. de Savoie, Savoie, France. Jakubick, A. T., and T. Franz (1993). Vacuum testing of the permeability of the excavation damaged zone, Rock Mech. Rock Engng., 26(2), 165-182. Patriarche, D., Pili, E., Adler, P. M., and J.-F. Thovert (2007). Stereological analysis of fractures in the Roselend tunnel and permeability determination, Water Resour. Res., 43, W09421. Richon, P., Perrier, F., Sabroux, J.-C., Trique, M., Ferry, C., Voisin, V., and E. Pili (2004). Spatial and time variations of radon-222 concentration in the atmosphere of a dead-end horizontal tunnel, J. Environ. Radioact., 78, 179-198. Richon, P., Perrier, F., Pili, E., and J.-C. Sabroux (2009). Detectability and significance of the 12hr barometric tide in radon-222 signal, dripwater flow rate, air temperature and carbon dioxide

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

    SciTech Connect

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

    1990-11-01

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

  18. Measurement of radon concentrations at Super-Kamiokande

    NASA Astrophysics Data System (ADS)

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

    1999-04-01

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

  19. Radon exhalation rate of some building materials used in Egypt.

    PubMed

    Maged, A F; Ashraf, F A

    2005-09-01

    Indoor radon has been recognized as one of the health hazards for mankind. Common building materials used for construction of houses, which are considered as one of the major sources of this gas in indoor environment, have been studied for exhalation rate of radon. Non-nuclear industries, such as coal fired power plants or fertilizer production facilities, generate large amounts of waste gypsum as by-products. Compared to other building materials waste gypsum from fertilizer production facilities (phosphogypsum) shows increased rates of radon exhalation. In the present, investigation solid state alpha track detectors, CR-39 plastic detectors, were used to measure the indoor radon concentration and the radon exhalation rates from some building materials used in Egypt. The indoor radon concentration and the radon exhalation rate ranges were found to be 24-55 Bq m(-3 )and 11-223 mBq m(-2) h(-1), respectively. The effective dose equivalent range for the indoor was found 0.6-1.4 mSv y(-1). The equilibrium factor between radon and its daughters increased with the increase of relative humidity.

  20. Intercomparison of active, passive and continuous instruments for radon and radon progeny

    SciTech Connect

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

    1995-12-31

    The DOE/OHER radon, thoron and progeny exposure and test facility was set up in 1993 to provide a well controlled, airtight and uniform environment. The new calibration chamber is the primary test facility at the Environmental Measurements Laboratory (EML), in which a large number of an diverse types of monitoring instruments can be accomodated for calibration, evaluation and intercomparison purposes. The test chamber is environmentally controlled for temperature and humidity. Monodispersed or polydispersed aerosols are generated to study radon and thoron progeny attachment and behavior and to investigate instrument performance under different conditions of exposure. Also, particle size measurements are performed to develop techniques for the assessment of the health risk from the inhalation of radon and thoron progeny. The results from the May 1995 intercomparison for active, passive and continuous instruments for radon and radon progeny are presented. Instruments that measure radon were represented by 13 participants with open face and diffusion barrier activated carbon collectors, 10 with nuclear alpha track detectors, 9 with short-term and long-term electret/ionization chambers and 13 with active and passive commercial electronic continuous monitors. For radon progeny, there were 4 participants that came in person to take part in the grab sampling methodology for measuring individual radon progeny and the potential alpha energy (PAEC). The results indicate that all the tested instruments that measure radon are in good standing. All instruments and methods used for grab sampling for radon progeny did very well. However, most of the continuous and integrating electronic instruments used for PAEC (WL), appear to underestimate the potential risk from radon progeny when the concentration of particles onto which the radon progeny are attached is <5,000 cc{sup -1}.

  1. Compilation of geogenic radon potential map of Pest County, Hungary

    NASA Astrophysics Data System (ADS)

    Szabó, K. Zs.; Pásztor, L.; Horváth, Á.; Bakacsi, Zs.; Szabó, J.; Szabó, Cs.

    2010-05-01

    222Rn and its effect on the human health have recently received major importance in environmental studies. This natural radioactive gas accounts for about 9% of lung cancer death and about 2% of all deaths from cancer in Europe due to indoor radon concentrations. It moves into the buildings from the natural decay chain of uranium in soils, rocks and building materials. Radon mapping regionalizes the average hazard from radon in a selected area as a radon risk map. Two major methods (concerning the applied radon data) have been used for mapping. One uses indoor radon data whereas the other is based on soil gas radon data. The outputs of the second approach are the geogenic radon potential maps. The principal objective of our work is to take the first step in geogenic radon mapping in Hungary. Soil samples collected in Pest County (Central Region of Hungary) in the frame of a countrywide soil survey (Soil Information and Monitoring System) were studied to have empirical information of the potential radon risk. As the first two steps radium concentration of soil samples, collected at 43 locations sampling soil profiles by genetic horizons from the surface level down to 60-150 cm, were determined using HPGe gamma-spectroscopy technique, as well as measurement of radon exhalation on the soil samples were carried out applying closed radon accumulation chamber coupled with RAD7 radon monitor detector. From these data the exhalation coefficient was calculated, which shows how many percent of the produced radon can come out from the sample. This rate strongly depends on the depth: at circa 100 cm a drastic decrease have been noticed, which is explained by the change in soil texture. The major source of indoor radon is the soil gas radon concentration (Barnet et al., 2005). We estimated this value from the measured radon exhalation and calculated soil porosity and density. The soil gas radon concentration values were categorized after Kemski et al. (2001) and then the

  2. Comparisons between soil radon and indoor radon

    SciTech Connect

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

    1999-10-01

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

  3. Monitoring spatiotemporal variations of diel radon concentrations in peatland and forest ecosystems based on neural network and regression models.

    PubMed

    Evrendilek, Fatih; Denizli, Haluk; Yetis, Hakan; Karakaya, Nusret

    2013-07-01

    Concentrations of outdoor radon-222 ((222)Rn) in temperate grazed peatland and deciduous forest in northwestern Turkey were measured, compared, and modeled using artificial neural networks (ANNs) and multiple nonlinear regression (MNLR) models. The best-performing multilayer perceptron model selected out of 28 ANNs considerably enhanced accuracy metrics in emulating (222)Rn concentrations relative to the MNLR model. The two ecosystems had similar diel patterns with the lowest (222)Rn concentrations in the afternoon and the highest ones near dawn. Mean level (5.1 + 2.5 Bq m(-3) h(-1)) of (222)Rn in the forest was three times smaller than that (15.8 + 9.7 Bq m(-3)) of (222)Rn in the peatland. Mean (222)Rn level had negative and positive relationships with air temperature and relative humidity, respectively.

  4. Dose assessment of population groups exposed to elevated radon levels in radioactive Italian spas

    SciTech Connect

    Sciocchetti, G.; Tosti, S.; Baldassini, P.G.; Sarao, R.; Soldano, E.

    1992-12-31

    The natural spring waters on the Isle of Ischia are among the most radioactive in the world. Therapeutic application of these waters, which contain very high radon concentrations, increases the radon exposure of people treated with them. People who live and work at radioactive spas may be good subjects for testing to evaluate detectable biological effects, especially because their exposures will be less influenced by synergistic factors than those of underground miners. The aim of our investigation was to characterize radon exposure for population groups exposed to high radon levels. Our approach takes into account some peculiar requirements of our epidemiological investigations. To obtain representative dose values, workers were classified into groups to obtain significant results suitable for epidemiological pilot studies. Investigations were carried out on the geological aspects of radon sources, environmental parameters, physical and dosimetric factors which influence radon levels, and related exposures in therapeutic facilities in order to model patterns of radon exposures for the various population groups. We inventoried hyper-radioactive springs on the island. We identified workers in radon spas who were exposed to radiation from inhaled radon daughters and retrospectively assessed their radon exposures. Results showed that, under some conditions, spa employees may have been exposed to much higher than usual levels of radon, which produced up to about 60 mSv y{sup -1} effective dose equivalent.

  5. Construction and measurements of an improved vacuum-swing-adsorption radon-mitigation system

    NASA Astrophysics Data System (ADS)

    Street, J.; Bunker, R.; Dunagan, C.; Loose, X.; Schnee, R. W.; Stark, M.; Sundarnath, K.; Tronstad, D.

    2015-08-01

    In order to reduce backgrounds from radon-daughter plate-out onto detector surfaces, an ultra-low-radon cleanroom is being commissioned at the South Dakota School of Mines and Technology. An improved vacuum-swing-adsorption radon mitigation system and cleanroom build upon a previous design implemented at Syracuse University that achieved radon levels of ˜0.2 Bq m-3. This improved system will employ a better pump and larger carbon beds feeding a redesigned cleanroom with an internal HVAC unit and aged water for humidification. With the rebuilt (original) radon mitigation system, the new low-radon cleanroom has already achieved a > 300× reduction from an input activity of 58.6 ± 0.7 Bq m-3 to a cleanroom activity of 0.13 ± 0.06 Bq m-3.

  6. Construction and measurements of an improved vacuum-swing-adsorption radon-mitigation system

    SciTech Connect

    Street, J. Bunker, R.; Dunagan, C.; Loose, X.; Schnee, R. W.; Stark, M.; Sundarnath, K.; Tronstad, D.

    2015-08-17

    In order to reduce backgrounds from radon-daughter plate-out onto detector surfaces, an ultra-low-radon cleanroom is being commissioned at the South Dakota School of Mines and Technology. An improved vacuum-swing-adsorption radon mitigation system and cleanroom build upon a previous design implemented at Syracuse University that achieved radon levels of ∼0.2 Bq m{sup −3}. This improved system will employ a better pump and larger carbon beds feeding a redesigned cleanroom with an internal HVAC unit and aged water for humidification. With the rebuilt (original) radon mitigation system, the new low-radon cleanroom has already achieved a > 300× reduction from an input activity of 58.6 ± 0.7 Bq m{sup −3} to a cleanroom activity of 0.13 ± 0.06 Bq m{sup −3}.

  7. Calibration system for measuring the radon flux density.

    PubMed

    Onishchenko, A; Zhukovsky, M; Bastrikov, V

    2015-06-01

    The measurement of radon flux from soil surface is the useful tool for the assessment of radon-prone areas and monitoring of radon releases from uranium mining and milling residues. The accumulation chambers with hollow headspace and chambers with activated charcoal are the most used devices for these purposes. Systematic errors of the measurements strongly depend on the geometry of the chamber and diffusion coefficient of the radon in soil. The calibration system for the attestation of devices for radon flux measurements was constructed. The calibration measurements of accumulation chambers and chambers with activated charcoal were conducted. The good agreement between the results of 2D modelling of radon flux and measurements results was observed. It was demonstrated that reliable measurements of radon flux can be obtained by chambers with activated charcoal (equivalent volume ~75 l) or by accumulation chambers with hollow headspace of ~7-10 l and volume/surface ratio (height) of >15 cm.

  8. A Study of the Permeation of Radon Through Geomembranes.

    NASA Astrophysics Data System (ADS)

    Mao, Xiaotian

    1990-01-01

    Geomembranes are thin sheets of polymeric materials which have been widely used as linings and covers of containers for liquid or solid waste. In this research various types and thicknesses of geomembranes were evaluated in order to determine which geomembranes could be used as suitable barriers for radon. The permeation of radioactive gases through geomembranes cannot be measured using the method described by the American Society for Testing and Materials (ASTM). The ASTM method estimates the permeation of a single pure gas through a polymeric membrane. The radioactivity of radon would be very high if this method was used. The method developed in this study utilized radon permeation scintillation cell which consisted of a source chamber, a measuring chamber, a radium source, and a geomembrane specimen. The concentration of radon within the source chamber and the measuring chamber was quantified by counting the alpha particles emitted by the decay of radon and its daughters. Based on the percentage of radon permeation through the membranes (defined as the reduction factor), the permeance was calculated. The data indicated that 0.8-mm thick geomembranes such as chlorinated polyethylene, polyurethane and ethylene interpolymer alloy provided a permeance that was less than 500 fmol m^{-2}s ^{-1} Pa^{ -1}. These geomembranes are suitable barriers for radon. The permeance of 0.15-mm polyethylene sheet, which has been used as a radon barrier, is 1.47 times 104 fmol m^{-2}s^ {-1} Pa^{-1} . The effect of certain parameters on radon permeation was quantitatively studied. Such parameters included the difference in air pressure between the two sides of a geomembrane, the thickness of the geomembrane, and the temperature. It was found that a difference of 5 cm Hg in air pressure between the two sides of a geomembrane did not significantly influence the radon permeation. Radon permeation decreased exponentially with increasing thickness of the geomembranes. Radon permeation

  9. Radon Mitigation for the SuperCDMS-SNOLAB Dark Matter Experiment

    NASA Astrophysics Data System (ADS)

    Street, Joseph; SuperCDMS Collaboration

    2016-03-01

    Experiments that seek to detect very rare processes, such as interactions of the dark matter particles thought to make up 85% of the mass of the universe, may suffer background interactions from radon daughters that have plated out onto detector surfaces. To reduce these backgrounds, an ultra-low-radon cleanroom was built at the South Dakota School of Mines & Technology. Cleanroom air is supplied by an optimized vacuum-swing-adsorption radon mitigation system that has achieved a > 300 × reduction from an input activity of 58.6 +/- 0.7 Bq/m3 to a cleanroom activity of 0.13 +/- 0.06 Bq/m3. Expected backgrounds due to radon daughters for the SuperCDMS dark matter search will be presented.

  10. What Is Radon?

    MedlinePlus

    ... Learn About Cancer » What Causes Cancer? » Other Carcinogens » Pollution » Radon Share this Page Close Push escape to ... can move into the air and into underground water and surface water. Radon is present outdoors and ...

  11. 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.

  12. Removal of long-lived {sup 222}Rn daughters by electropolishing thin layers of stainless steel

    SciTech Connect

    Schnee, R. W.; Bowles, M. A.; Bunker, R.; McCabe, K.; White, J.; Cushman, P.; Pepin, M.; Guiseppe, V. E.

    2013-08-08

    Long-lived alpha and beta emitters in the {sup 222}Rn decay chain on detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay. Removal of tens of microns of material via electropolishing has been shown to be effective at removing radon daughters implanted into material surfaces. Some applications, however, require the removal of uniform and significantly smaller thicknesses. Here, we demonstrate that electropolishing < 1 μm from stainless-steel plates reduces the contamination efficiently, by a factor > 100. Examination of electropolished wires with a scanning electron microscope confirms that the thickness removed is reproducible and reasonably uniform. Together, these tests demonstrate the effectiveness of removal of radon daughters for a proposed low-radiation, multi-wire proportional chamber (the BetaCage), without compromising the screener’s energy resolution. More generally, electropolishing thin layers of stainless steel may effectively remove radon daughters without compromising precision-machined parts.

  13. Development and management of a radon assessment strategy suitable for underground railway tunnelling projects.

    PubMed

    Purnell, C J; Frommer, G; Chan, K; Auch, A A

    2004-01-01

    The construction of underground tunnels through radon-bearing rock poses a radiation health risk to tunnelling workers from exposure to radon gas and its radioactive decay products. This paper presents the development and practical application of a radon assessment strategy suitable for the measurement of radon in tunnelling work environments in Hong Kong. The assessment strategy was successfully evaluated on a number of underground railway tunnelling projects over a 3 y period. Radon measurements were undertaken using a combination of portable radon measurement equipment and track etch detectors (TEDs) deployed throughout the tunnels. The radon gas monitoring results were used to confirm that ventilation rates were adequate or identified, at an early stage, when further action to reduce radon levels was required. Exposure dose estimates based on the TED results showed that the exposure of tunnel workers to radon did not exceed 3 mSv per annum for the duration of each project. PMID:15103065

  14. Mapping the geogenic radon potential of the eastern Canary Islands.

    NASA Astrophysics Data System (ADS)

    Rubiano, Jesús G.; Alonso, Hector; Arnedo, Miguel. A.; Tejera, Alicia; Martel, Pablo; Gil, Juan M.; Rodriguez, Rafael; González, Jonay

    2014-05-01

    The main contribution of indoor radon comes from soils and thus, the knowledge of the concentration of this gas in soils is important for estimating the risk of finding high radon indoor concentrations. To characterize the behavior of radon in soils, it is common to use the a quantity named Radon Potential which results of a combination of properties of the soil itself and from the underlying rock, such as concentration and distribution of radium, porosity, permeability, the moisture content and meteorological parameters, among others. In this work, the results three year of campaigns of measurement radon gas as well as the permeability in soils of the Eastern Canary Islands (Gran Canaria, Fuerteventura and Lanzarote) are presented. By combining these two parameters and through the use of geostatistic interpolation techniques, the radon potential of soils is estimated and it is used to carry on a classification of the territory into hazard zones according to their potential for radon emanation. To measure the radon soil gas a probe equipped with a "lost" sharp tip is inserted to the desired sampling depth. One of the characteristics of the Canary Islands is the absence of developed soils and so the bedrock is found typically at very shallow depth. This fact has led us to adopt a sampling depth of 50 cm at most. The probe is connected to the continuous radon monitor Durridge RAD7 equipped with a solid-state alpha spectrometer to determine concentration radon using the activity its short-lived progeny. Dried soil air is delivered to the RAD7 radon monitor by pumping. A half hour counting time for all sampling points has been taken. In parallel to the radon measurement campaign, the permeability of soils has also been determined at each point using the permeameter RADON-JOK. The principle of operation of this equipment consists of air withdrawal by means of negative pressure. The gas permeability is then calculated using the known flow of air flowing through the probe

  15. Detection of radon decay products in rainwater.

    PubMed

    Baker, S I

    1999-11-01

    The Argonne National Laboratory-East (ANL-E) Environmental Radiation Monitoring System measures and records ambient radiation levels and provides detection capability for radon decay products in rain clouds. These decay products in rainwater tracked into a facility on the shoes of workers can cause false alarms from hand and shoe monitors. The monitors at ANL-E can easily detect the radon decay products, and the 19.6 and 26.8 min half-lives of the beta-particle emitters are long enough in many cases for sufficient activity to still be present to initiate a contamination alarm when the shoes are checked for radioactivity. The Environmental Radiation Monitoring System provides a warning when precipitation contains elevated levels of radon decay products. It is based on a prototype developed at the Super Collider Laboratory. During its first year of operation there were nine alarms from radon decay products with an alarm trigger point set at 30% greater than background. The alarms occurred at both monitoring stations, which are approximately 1,000 m apart, indicating large diameter radon clouds. The increases in background were associated with low atmospheric pressure. There was no correlation with radon released from the coal-burning steam plant on the site. Alarms also occurred when short-lived accelerator-produced radioactivity in the exhaust stack plume passed over the NaI(Tl) detector in one of the stations. The 450 MeV proton accelerator near the station produced 12C, 13N, and 15O by spallation of air nuclei. The gamma-ray spectrum from the plume from the accelerator exhaust stack was dominated by the 511 keV annihilation gamma rays from decay of these radionuclides. These gamma rays were easily distinguished from the 609 keV, 1,120 keV, and 1,764 keV gamma rays emitted by the radon decay products.

  16. Discrimination of airborne radioactivity from radon progeny

    SciTech Connect

    Ching-Jiang Chen; Pao-Shan Weng; Tieh-Chi Chu

    1994-05-01

    Naturally occurring radon and thoron progeny are the most interfering nuclides in the aerosol monitoring system. The high background and fluctuation of natural radioactivity on the filter can cause an error message to the aerosol monitor. A theoretical model was applied in the simulation of radon and thoron progeny behavior in the environment and on the filter. Results show that even a small amount of airborne nuclides on the filter could be discriminated by using the beta:alpha activity ratio instead of gross beta or alpha counting. This method can increase the sensitivity and reliability of real-time aerosol monitoring. 8 refs., 11 figs., 3 tabs.

  17. Radon Concentration in the Cataniapo-Autana River Basin, Amazonas State, Venezuela

    NASA Astrophysics Data System (ADS)

    Sajo-Bohus, L.; Greaves, E. D.; Alvarez, H.; Liendo, J.; Vásquez, G.

    2007-10-01

    Radon activity concentration is measured in rivers of the Autana-Cataniapo hydrologic basin. The region experiments mining and it is forecasted that the basin will be perturbed. Radon activity monitoring is one of the methods to measure environmental changes. Values of radon concentration in water range between 0.4 and 30 Bq L-1.

  18. Dependency of radon entry on pressure difference

    NASA Astrophysics Data System (ADS)

    Kokotti, H.; Kalliokoski, P.; Jantunen, M.

    Radon levels, ventilation rate and pressure differences were monitored continuously in four apartment houses with different ventilation systems. Two of them were ventilated by mechanical exhaust, one by mechanical supply and exhaust, and one by natural ventilation. The two-storey houses were constructed from concrete elements on a slab and located on a gravel esker. It was surprising to find that increasing the ventilation rate increased levels of radon in the apartments. Increased ventilation caused increased outdoor-indoor pressure difference, which in turn increased the entry rate of radon and counteracted the diluting effect of ventilation. The increase was significant when the outdoor-indoor pressure difference exceeded 5 Pa. Especially in the houses with mechanical exhaust ventilation the pressure difference was the most important factor of radon entry rate, and contributed up to several hundred Bq m -3 h -1.

  19. Radon in earth-sheltered structures

    USGS Publications Warehouse

    Landa, E.R.

    1984-01-01

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

  20. Long term performance of radon mitigation systems

    SciTech Connect

    Prill, R.; Fisk, W.J.

    2002-03-01

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

  1. Radon and lung cancer

    SciTech Connect

    Samet, J.M.

    1989-05-10

    Radon, an inert gas released during the decay of uranium-238, is ubiquitous in indoor and outdoor air and contaminates many underground mines. Extensive epidemiologic evidence from studies of underground miners and complementary animal data have documented that radon causes lung cancer in smokers and nonsmokers. Radon must also be considered a potentially important cause of lung cancer for the general population, which is exposed through contamination of indoor air by radon from soil, water, and building materials. This review describes radon's sources, levels in U.S. homes, dosimetry, the epidemiologic evidence from studies of miners and the general population, and the principal, recent risk assessments.91 references.

  2. 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.

  3. Radon and lung cancer.

    PubMed

    Samet, J M

    1989-05-10

    Radon, an inert gas released during the decay of uranium-238, is ubiquitous in indoor and outdoor air and contaminates many underground mines. Extensive epidemiologic evidence from studies of underground miners and complementary animal data have documented that radon causes lung cancer in smokers and nonsmokers. Radon must also be considered a potentially important cause of lung cancer for the general population, which is exposed through contamination of indoor air by radon from soil, water, and building materials. This review describes radon's sources, levels in U.S. homes, dosimetry, the epidemiologic evidence from studies of miners and the general population, and the principal, recent risk assessments.

  4. Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

    SciTech Connect

    George, A.C.; Knutson, E.O.; Tu, K.W.; Fisenne, I.M.

    1995-12-01

    The results from the May 1995 Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurement conducted in the EML radon exposure and test facility are presented. Represented were 13 participants that measure radon with open faced and diffusion barrier activated carbon collectors, 10 with nuclear alpha track detectors, 9 with short-term and long-term electret/ionization chambers, and 13 with active and passive commercial electronic continuous monitors. For radon progeny, there were four participants that came in person to take part in the grab sampling methodology for measuring individual radon progeny and the potential alpha energy concentration (PAEC). There were 11 participants with continuous and integrating commercial electronic instruments that are used for measuring the PAEC. The results indicate that all the tested instruments that measure radon fulfill their intended purpose. All instruments and methods used for grab sampling for radon progeny did very well. However, most of the continuous and integrating electronic instruments used for measuring the PAEC or working level appear to underestimate the potential risk from radon progeny when the concentration of particles onto which the radon progeny are attached is <5,000 cm{sup -3}.

  5. 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.

  6. Radon in Wisconsin.

    PubMed

    Weiffenbach, C; Anderson, H A

    2000-11-01

    Owners of about 15% to 20% of the homes in Wisconsin have tested their indoor air for the carcinogenic gas radon. Five percent to 10% of homes have year-average main-floor radon levels that exceed the US Environmental Protection Agency (EPA) exposure guideline, and they are found in most regions of the state. Attempting to retroactively seal foundations to keep radon from the ground out of a home is largely ineffective. However, a soil-depressurization radon mitigation system is highly effective for existing houses, and new homes can easily be built radon-resistant. As the number of homeowners obtaining needed repairs increases, significant lung cancer risk reduction is being achieved in a voluntary, non-regulatory setting. In coming years, as radon in community drinking water supplies becomes regulated under the federal 1996 Safe Drinking Water Act, the "multimedia" option of the act may result in additional attention to mitigation of radon in indoor air. PMID:11149257

  7. Low pressure radon diffusion - A laboratory study and its implications for lunar venting

    NASA Technical Reports Server (NTRS)

    Friesen, L. J.; Adams, J. A. S.

    1976-01-01

    Results of a study of radon migration through columns of fine particulate materials, at total pressures of 0.02-0.2 torr, are reported. Materials studied were: NBS Glass Spheres (SRM 1003), Emerson & Cuming Eccospheres (IG-101), activated coconut charcoal, Lipaci obsidian, and W-1 Standard Diabase. Rates of diffusion were used to derive heats of adsorption for radon on the materials tested. The most reliable values found clustered around 8-9 kcal/mole. These high heats of adsorption, if typical for most materials, combined with low percentages of radon emanation by lunar soils found by other researchers, imply that random walk diffusion will not be an important mechanism for redistributing the radon and the radon daughters produced in the lunar regolith. In particular, since random walk migration is not a sufficient mechanism to account for localized high concentrations of radon-222 and its daughter polonium-210 observed by the Apollo 15 and 16 command modules, an alternative mechanism is proposed, in which radon would be swept to the surface by other gases during intermittent venting events.

  8. Residential radon exposure and risk of lung cancer in Missouri.

    PubMed Central

    Alavanja, M C; Lubin, J H; Mahaffey, J A; Brownson, R C

    1999-01-01

    OBJECTIVES: This study investigated residential radon exposure and lung cancer risk, using both standard radon dosimetry and a new radon monitoring technology that, evidence suggests, is a better measure of cumulative radon exposure. METHODS: Missouri women (aged 30 to 84 years) newly diagnosed with primary lung cancer during the period January 1, 1993, to January 31, 1994, were invited to participate in this population-based case-control study. Both indoor air radon detectors and CR-39 alpha-particle detectors (surface monitors) were used. RESULTS: When surface monitors were used, a significant trend in lung cancer odds ratios was observed for 20-year time-weighted-average radon concentrations. CONCLUSIONS: When surface monitors were used, but not when standard radon dosimetry was used, a significant lung cancer risk was found for radon concentrations at and above the action level for mitigation of houses currently used in the United States (148 Bqm-3). The risk was below the action level used in Canada (750 Bqm-3) and many European countries (200-400 Bqm-3). PMID:10394313

  9. We Are Our Mothers' Daughters?

    ERIC Educational Resources Information Center

    Grady, Marilyn L.; LaCost, Barbara Y.

    2004-01-01

    Writing that makes one think, writing that enriches one's understanding of the past and present, that's what Cokie Roberts' book, "We Are Our Mothers' Daughters" provides, and that, too, is what the authors of this issue of the "Journal of Women in Educational Leadership" provide. Roberts' background as a news analyst covering politics, Congress…

  10. Intercomparison of active and passive instruments for radon and radon progeny in North America

    SciTech Connect

    George, A.C.; Tu, Keng-Wu; Knutson, E.O.

    1995-02-01

    An intercomparison exercise for radon and radon progeny instruments and methods was held at the Environmental Measurements Laboratory (EML) from April 22--May 2, 1994. The exercise was conducted in the new EML radon test and calibration facility in which conditions of exposure are very well controlled. The detection systems of the intercompared instruments consisted of. (1) pulse ionization chambers, (2) electret ionization chambers, (3) scintillation detectors, (4) alpha particle spectrometers with silicon diodes, surface barrier or diffused junction detectors, (5) registration of nuclear tracks in solid-state materials, and (6) activated carbon collectors counted by gamma-ray spectrometry or by alpha- and beta-liquid scintillation counting. 23 private firms, government laboratories and universities participated with a 165 passive integrating devices consisting of: Activated carbon collectors, nuclear alpha track detectors and electret ionization chambers, and 11 active and passive continuous radon monitors. Five portable integrating and continuous instruments were intercompared for radon progeny. Forty grab samples for radon progeny were taken by five groups that participated in person to test and evaluate their primary instruments and methods that measure individual radon progeny and the potential alpha energy concentration (PAEC) in indoor air. Results indicate that more than 80% of the measurements for radon performed with a variety of instruments, are within {plus_minus}10% of actual value. The majority of the instruments that measure individual radon progeny and the PAEC gave results that are in good agreement with the EML reference value. Radon progeny measurements made with continuous and integrating instruments are satisfactory with room for improvement.

  11. Construction and measurements of a vacuum-swing-adsorption radon-mitigation system

    SciTech Connect

    Schnee, R. W.; Bunker, R.; Ghulam, G.; Jardin, D.; Kos, M.; Tenney, A. S.

    2013-08-08

    Long-lived alpha and beta emitters in the {sup 222}Rn decay chain on (and near) detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay, and in screening detectors. In order to reduce backgrounds from radon-daughter plate-out onto the wires of the Beta Cage during its assembly, an ultra-low-radon cleanroom is being commissioned at Syracuse University using a vacuum-swing-adsorption radon-mitigation system. The radon filter shows ∼20× reduction at its output, from 7.47±0.56 to 0.37±0.12 Bq/m{sup 3}, and the cleanroom radon activity meets project requirements, with a lowest achieved value consistent with that of the filter, and levels consistently < 2 Bq/m{sup 3}.

  12. Construction and measurements of a vacuum-swing-adsorption radon-mitigation system

    NASA Astrophysics Data System (ADS)

    Schnee, R. W.; Bunker, R.; Ghulam, G.; Jardin, D.; Kos, M.; Tenney, A. S.

    2013-08-01

    Long-lived alpha and beta emitters in the 222Rn decay chain on (and near) detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double beta decay, and in screening detectors. In order to reduce backgrounds from radon-daughter plate-out onto the wires of the Beta Cage during its assembly, an ultra-low-radon cleanroom is being commissioned at Syracuse University using a vacuum-swing-adsorption radon-mitigation system. The radon filter shows ˜20× reduction at its output, from 7.47±0.56 to 0.37±0.12 Bq/m3, and the cleanroom radon activity meets project requirements, with a lowest achieved value consistent with that of the filter, and levels consistently < 2 Bq/m3.

  13. Radon optical processing in radon space

    NASA Astrophysics Data System (ADS)

    Barrett, H. H.

    1986-06-01

    The stated goals of the Radon program were: (1) Theoretical investigation of the role of the Radon transform in signal processing, including enumeration of the operations achievable in Radon space. (2) Construction of a practical system for two dimensional spectral analysis and image filtering. (3) Proof-of-principle experiments for other processing operations, such as bandwidth compression and calculation of the Wigner distribution function. (4) Determination of the feasibility of Radon-space processing of three dimensional data, emphasizing not only system architecture but also storage media capable of saving rapidly retrieving the requisite data arrays. Several 2D signal-processing operations are discovered susceptible to solution in Radon space. These include the Hartley transform, certain joint coordinate-frequency representations (e.g., the Wigner distribution function and Woodward ambiguity functions), certain algorithms for spectrum estimation (e.g., the periodogram and the Yule Walker autoregressive model), and the cepstrum. Most of these Radon space operations have been demonstrated in computer simulations and some have been performed by means of analog hardware in the hybrid Radon space signal processing system. This system can perform a family of processing operations at about five frames per second, limited by the image-rotation rate. Processing is performed by surface acoustic wave (SAW) filters, and the 2D processed signal is displayed on a CRT.

  14. Recoil-deposited Po-210 in radon dwellings

    SciTech Connect

    Samuelsson, C.

    1990-12-31

    Short-lived decay products of Rn-222 plate out on all surfaces in a house containing radon gas. Following the subsequent alpha decays of the mother nuclei, the daughter products Pb-214 and Pb-210 are superficially and permanently absorbed. Due to its long half-life (22 y) the activity of absorbed Pb-210 accumulates in the surface. The activity of Pb-210, or its decay products, can thus reflect the past randon daughter and plate-out history of a house over several decades. Our results and experience from measurements of Po-210 and Rn-222 in 22 dwellings will be presented. In these studies the Po-210 surface activity of one plane glass sheet per dwelling (window panes were not used) has been determined and compared with the period of exposure times the mean radon concentration measured over a two-month period. Considering the large uncertainty in the integrated radon exposure estimate the surface {sup 210}Po correlates well (r=0.73) with the accumulated radon exposure. The {sup 210}Po activity of the glass samples has been measured non-destructively using an open-flow pulse ionization chamber and this detector has also been successfully applied in field exercises.

  15. Removal of {sup 222}Rn daughters from metal surfaces

    SciTech Connect

    Zuzel, G.; Wojcik, M.; Majorovits, B.; Lampert, M. O.; Wendling, P.

    2015-08-17

    Removal of the long-lived {sup 222}Rn daughters ({sup 210}Pb, {sup 210}Bi and {sup 210}Po) from copper, stainless steel and germanium surfaces was investigated. As cleaning techniques etching and electro-polishing was applied to samples in a form of discs exposed earlier to a strong radon source. Reduction of the {sup 210}Pb activity was tested using a HPGe spectrometer, for {sup 210}Bi a beta spectrometer and for {sup 210}Po an alpha spectrometer was used. According to the conducted measurements electro-polishing was always more efficient compared to etching and in case of copper the activity reduction factors for {sup 210}Pb, {sup 210}Bi and {sup 210}Po were between 200 and 400. Etching does not remove {sup 210}Po from copper but works very efficiently from germanium. Results obtained for {sup 210}Pb and {sup 210}Bi for etched stainless steel were worse but still slightly better than those achieved for copper.

  16. [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.

  17. 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

  18. 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

  19. 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)

  20. The new risk estimates and exposures to radon in high grade uranium mines

    SciTech Connect

    Brown, L.D. )

    1992-09-01

    The DS86 dosimetry used by the Radiation Effects Research Foundation, in re-evaluating radiation exposure risks from the atom bomb survivor lifespan studies, has led directly to a significant reduction in the maximum permissible dose recommended by the International Commission on Radiological Protection. In the case of uranium miners the contribution to the total dose resulting from the inhalation of radon daughters continues to be assessed in accordance with the procedures recommended in ICRP Report 47, which means that there has been no change in the maximum permissible radon daughter exposure limit. ICRP intends to review this situation once the new report of their task force on lung dosimetry has been adopted. This paper suggests that the direct epidemiological data on the risks of radon daughter inhalation is more satisfactory than indirect estimates of risk based on a lung dosimetry model, and that this direct evidence does not justify any increase in the presently accepted risk factor associated with radon daughter inhalation.

  1. Optimistic biases in public perceptions of the risk from radon.

    PubMed Central

    Weinstein, N D; Klotz, M L; Sandman, P M

    1988-01-01

    Survey data were obtained from a random sample of 657 homeowners in New Jersey and also from 141 homeowners who had already monitored their homes for radon. People who had not tested tended to believe that they were less at risk than their neighbors, and they interpreted ambiguous predictors of home radon levels in ways that supported their beliefs of below-average risk. Residents who had already tested their homes were relatively accurate about the probability of health effects. In both groups less than half of those who knew that radon can cause lung cancer were willing to admit that it would be serious if they suffered health effects from this source. The optimistic biases of the public may hamper attempts to encourage home radon monitoring and to promote appropriate mitigation measures in homes with elevated radon concentrations. Images FIGURE 1 PMID:3381955

  2. Optimistic biases in public perceptions of the risk from radon

    SciTech Connect

    Weinstein, N.D.; Klotz, M.L.; Sandman, P.M.

    1988-07-01

    Survey data were obtained from a random sample of 657 homeowners in New Jersey and also from 141 homeowners who had already monitored their homes for radon. People who had not tested tended to believe that they were less at risk than their neighbors, and they interpreted ambiguous predictors of home radon levels in ways that supported their beliefs of below-average risk. Residents who had already tested their homes were relatively accurate about the probability of health effects. In both groups less than half of those who knew that radon can cause lung cancer were willing to admit that it would be serious if they suffered health effects from this source. The optimistic biases of the public may hamper attempts to encourage home radon monitoring and to promote appropriate mitigation measures in homes with elevated radon concentrations.

  3. Parent characteristics linked with daughters' attachment styles.

    PubMed

    Kilmann, Peter R; Vendemia, Jennifer M C; Parnell, Michele M; Urbaniak, Geoffrey C

    2009-01-01

    This study investigated links between parent characteristics and daughters' attachment styles for 90 female undergraduates and their married biological parents. Parents with a secure attachment pattern were rated as more accepting, less controlling, more competent, and more consistent in showing love and affection to their daughter in contrast to parents with an insecure attachment pattern. Significant positive associations were found between mothers' fearful attachment scores and the fearful, preoccupied, and dismissive attachment scores of daughters. Daughters of matched secure parents were more likely to report a secure attachment style, while daughters of matched insecure parents were more likely to report an insecure attachment style.

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

    DOE PAGESBeta

    Keefer, G.; Grant, C.; Piepke, A.; Ebihara, T.; Ikeda, H.; Kishimoto, Y.; Kibe, Y.; Koseki, Y.; Ogawa, M.; Shirai, J.; et al

    2014-09-28

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

  5. Radon and lung cancer.

    PubMed

    Sethi, Tarsheen K; El-Ghamry, Moataz N; Kloecker, Goetz H

    2012-03-01

    Lung cancer is the leading cause of cancer-related deaths worldwide. Radon exposure is the second leading cause of lung cancer, following tobacco smoke. Radon is not only an independent risk factor; it also increases the risk of lung cancer in smokers. Numerous cohort, case-control, and experimental studies have established the carcinogenic potential of radon. The possibility of radon having a causative effect on other cancers has been explored but not yet proven. One of the postulated mechanisms of carcinogenesis is DNA damage by alpha particles mediated by the production of reactive oxygen species. The latter are also thought to constitute one of the common mechanisms underlying the synergistic effect of radon and tobacco smoke. With an estimated 21,000 lung cancer deaths attributable to radon in the United States annually, the need for radon mitigation is well acknowledged. The Environmental Protection Agency (EPA) has established an indoor limit of 4 picocuries (pCi)/L, and various methods are available for indoor radon reduction when testing shows higher levels. Radon mitigation should accompany smoking cessation measures in lung cancer prevention efforts.

  6. The reliability of radon as seismic precursor

    NASA Astrophysics Data System (ADS)

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

    2016-04-01

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

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

    SciTech Connect

    Genrich, V.

    1995-12-31

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

  8. 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.

  9. Residential Radon Exposure and Risk of Lung Cancer in Missouri

    Cancer.gov

    A case-control study of lung cancer and residential radon exposure in which investigators carried out both standard year-long air measurements and CR-39 alpha detector measurements (call surface monitors)

  10. 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

  11. Envitonmental monitoring and radiation protection in Škocjan Caves, Slovenia

    NASA Astrophysics Data System (ADS)

    Debevec Gerjeviè, V.; Jovanovič, P.

    2012-04-01

    Škocjan Caves were listed as UNESCO World Heritage Sites in 1986, due to their exceptional significance for cultural and natural heritage. Park Škocjan Caves is located in South Eastern part of Slovenia. It was established with aim of conserving and protecting exceptional geomorphological, geological and hydrological outstanding features, rare and endangered plant and animal species, paleontological and archaeological sites, ethnological and architectural characteristics and cultural landscape and for the purpose of ensuring opportunities for suitable development, by the National Assembly of the Republic of Slovenia in 1996. Park Škocjan Caves established monitoring that includes caves microclimate parameters: humidity, CO2, wind flow and radon concentration and daughter products. The approach in managing the working place with natural background radiation is complex. Monitoring of Radon has been functioning for more than ten years now. Presentation will show the dynamic observed in the different parts of the caves, related to radon daughter products and other microclimatic data. Relation of background radiation to carrying capacity will be explained. Implementing the Slovene legislation in the field of radiation protection, we are obligated to perform special measurements in the caves and also having our guides and workers in the caves regularly examined according to established procedure. The medical exams are performed at Institution of Occupational Safety, Ljubljana in order to monitor the influence of Radon to the workers in the cave. The equivalent dose for each employed person is also established on regular basis and it is part of medical survey of workers in the caves. A system of education of the staff working in the caves in the field of radiation protection will be presented as well.

  12. Radon exposure mediated changes in lung macrophage morphology and function, in vitro

    SciTech Connect

    Seed, T.M.; Niiro, G.K.; Kretz, N.D.

    1990-01-01

    Bronchopulmonary macrophages play a key role in the normal physiology of the respiratory system. Potential respiratory dysfunctions due to radon/radon daughter exposure-mediated damage of the macrophage lung cell population has been explored via in vitro technology. In this study, macrophages were isolated from lungs of normal healthy dogs by saline lavage, cultured for varying periods (0-96 h) in the presence or absence of radon gas, and assessed for radon dose-dependent changes in cell morphology and function. The in vitro culture procedure and the cell exposing system allowed for detailed alpha particle dosimetry, in relation to the assessed biological end points; i.e. (1) exposure-dependent changes in macrophage surface topography, (2) capacity to elaborate specific growth factor (CSF) essential for self maintenance, and (3) alterations in cell viability. Highlights of the morphologic assessment indicate that relatively low alpha particle doses arising from protracted radon/radon daughter exposure elicites pronounced topographic alterations of the exposed macrophage's cell surface. 27 refs., 7 figs., 1 tab.

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

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

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

  15. 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.

  16. Construction, Testing, and Analysis of Radon Mitigation System

    NASA Astrophysics Data System (ADS)

    Jardin, Dan; Schnee, Richard; CDMS Collaboration

    2011-10-01

    The search for dark matter or other rare events such as neutrinoless double-beta decay is difficult in the presence of background radiation such as the alpha and beta emissions from the 222Rn decay chain. In order to reduce the radioactive background from Rn-daughters, an ultra-low radon clean room is being built at Syracuse University. A vacuum-swing adsorption system is used to mitigate the radon. Air flows through one of two tanks filled with charcoal that the radon adsorbs to, allowing the filtered air to pass into the clean room. Computer-controlled valves direct the airflow so that one tank filters the air while the other tank is purged of radon by circulating a small fraction of the cleaned airflow back through the tank at low pressure. The durations, pressures, and flow rates of each stage of building pressure, filtering, releasing pressure, and purging in the tanks are optimized in order to maximize the reduction of radon from the air. Professor.

  17. 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. PMID:24705248

  18. 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...

  19. 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)

  20. 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

  1. Chemical properties of radon

    SciTech Connect

    Stein, L.

    1986-01-01

    Radon is frequently regarded as a totally inert element. It is, however, a ''metalloid'' - an element which lies on the diagonal of the Periodic Table between the true metals and nonmetals and which exhibits some of the characteristics of both. It reacts with fluorine, halogen fluorides, dioxygenyl salts, fluoro-nitrogen salts, and halogen fluoride-metal fluoride complexes to form ionic compounds. Several of the solid reagents can be used to collect radon from air but must be protected from moisture, since they hydrolyze readily. Recently, solutions of nonvolatile, cationic radon have been produced in nonaqueous solvents. Ion-exchange studies have shown that the radon can be quantitatively collected on columns packed with either Nafion resins or complex salts. In its ionic state, radon is able to displace H/sup +/, Na/sup +/, K/sup +/, Cs/sup +/, Ca/sup 2 +/, and Ba/sup 2 +/ ions from a number of solid materials. 27 refs., 6 figs.

  2. Determination and measurement of soil parameters for characterizing radon hazard of soils

    SciTech Connect

    Blue, T.E.; Jarzemba, M.S.

    1992-12-31

    There is little correlation between radon concentrations in soil and radon concentrations in homes. One explanation is that the soil radon concentration does not fully characterize the soil as a radon hazard. A mathematical model for the determination of important soil parameters for characterizing the flow of radon into a basement has been analyzed. We have identified important soil properties by mathematically modeling ventilated air enclosed in basement walls of thickness T (through which radon convects) and surrounded by soil of infinite extent (through which radon diffuses). The radon instantaneously mixed uniformly with the basement air and is lost from the basement air by ventilation ({lambda}{sub v}) and decay ({lambda}). It was found that not only the soil pore gas radon concentration, C{sub s}, but also the radon gas diffusion length, L{sub 3}, and the soil porosity, {epsilon}{sub 3}, are important to characterize the soil as a radon hazard. A model for determining the parameters C{sub s}, L{sub 3}, and {epsilon}{sub 3} has also been analyzed. It was found that it is possible to measure in situ these important soil parameters by monitoring the radon gas concentration time history of two cavities of different radii formed in the same soil.

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

    PubMed

    Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

    2013-02-01

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

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

    PubMed

    Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

    2013-02-01

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

  5. The use of radon as tracer in environmental sciences

    NASA Astrophysics Data System (ADS)

    Quindos Poncela, Luis; Sainz Fernandez, Carlos; Fuente Merino, Ismael; Gutierrez Villanueva, Jose; Gonzalez Diez, Alberto

    2013-08-01

    Radon can be used as a naturally occurring tracer for environmental processes. By means of grab-sampling or continuous monitoring of radon concentration, it is possible to assess several types of dynamic phenomena in air and water. We present a review of the use of radon and its progeny at the University of Cantabria. Radon can be an atmospheric dynamics indicator related with air mass interchange near land-sea discontinuities as well as for the study of vertical variations of air parameters (average values of different types of stability: 131-580 Bq m-3). Concerning indoor gas, we present some results obtained at Altamira Cave (Spain): from 222 to 6549 Bq m-3 (Hall) and from 999 to 6697 Bq m-3 (Paintings Room). Finally, variations of radon concentration in soil (0.3 to 9.1 kBq m-3) and underground water (values up to 500 Bq l-1) provide relevant information about different geophysical phenomena.

  6. Realization of radioactive equilibrium in the KRISS radon chamber.

    PubMed

    Lee, Mo Sung; Park, Tae Soon; Lee, Jong Man

    2013-11-01

    The maintenance of radioactive equilibrium between radon and its decay products in a radon chamber is necessary to calibrate radon decay product monitors. In this study, the activity concentrations of radon decay products have been measured, and mosquito-repellent incense has been used to produce aerosol particles in the chamber. Filter papers with 8 μm pore size were used to collect aerosol in the chamber. The activity concentrations of radon decay products have been evaluated by the Modified Tsivoglou Method. The correction factors due to the differences in counting time requirements of the Modified Tsivoglou Method and the time delay between consecutive measurements have been determined. Finally, the radioactive equilibrium has been confirmed by applying the Bateman equation.

  7. Preseismic changes in atmospheric radon concentration and crustal strain

    NASA Astrophysics Data System (ADS)

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

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

  8. 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.

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

    PubMed

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

    2015-08-01

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

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

    PubMed

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

    2014-10-01

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

  11. Comparison of two methods for high purity germanium detector efficiency calibration for charcoal canister radon measurement.

    PubMed

    Nikolic, J; Pantelic, G; Zivanovic, M; Rajacic, M; Todorovic, D

    2014-11-01

    The charcoal canister method of radon measurement according to US Environment Protection Agency protocol 520/5-87-005 is widely used for screening. This method is based on radon adsorption on coal and measurement of gamma radiation of radon daughters. For the purpose of gamma spectrometry, appropriate efficiency calibration of the measuring system must be performed. The most usual method of calibration is using standard canister, a sealed canister with the same matrix and geometry as the canisters used for measurements, but with the known activity of radon. In the absence of standard canister, a different method of efficiency calibration has to be implemented. This study presents the results of efficiency calibration using the EFFTRAN efficiency transfer software. Efficiency was calculated using a soil matrix cylindrical secondary reference material as a starting point. Calculated efficiency is then compared with the one obtained using standard canister and applied to a realistic measurement in order to evaluate the results of the efficiency transfer.

  12. {sup 210}Po as a long-term integrating radon indicator in the indoor environment. Final report

    SciTech Connect

    Not Available

    1992-12-31

    Exposure to radon (Rn-222) decay products in the indoor environment is suspected of being a significant lung cancer agent in many countries. But quantification of the contemporary lung cancer risk (i.e. probability) on an individual basis is not an easy task. Only past exposures are relevant and assessing individual exposures in retrospect is associated with large uncertainties, if possible at all. One way to extend the validity of contemporary measurements to past decades is to measure long-lived decay products of radon, the long-lived radon daughters. After our laboratory had exemplified the correlation between implanted Po-210 and the estimated radon exposures in six different dwellings, the US Department of Energy and the Swedish Radiation Protection Institute granted funds for a one-year study, ``{sup 210}Po as a Long-Term Integrating Radon Indicator in the Indoor Environment.`` In this report the work performed under these two contracts is reported.

  13. Improvement in understanding the deposition of ambient dust particles on ECAM (environmental continuous air monitor) filters, reduction of the alpha-particle interference of radon progeny and other radioactive aerosols in different particle size ranges on filters, and development of ECAMs with increased sensitivity under dusty outdoor conditions.

    SciTech Connect

    Schery, Stephen D., Wasiolek, Piotr; Rodgers, John

    1999-06-01

    Improvement in understanding the deposition of ambient dust particles on ECAM (environmental continuous air monitor) filters, reduction of the alpha-particle interference of radon progeny and other radioactive aerosols in different particle size ranges on filters, and development of ECAMs with increased sensitivity under dusty outdoor conditions.

  14. Effects of thoron on a radon detector of pulse-ionization chamber type.

    PubMed

    Ishikawa, T

    2004-01-01

    A radon detector of pulse-ionization chamber (PIC) type could have some sensitivity for thoron. Thus, the presence of thoron could interfere with precise measurement of radon. In the present study, effects of thoron on the most common type of PIC detector (commercial name AlphaGUARD) were investigated using an exposure chamber. The AlphaGUARD was exposed to a mixture of radon and thoron, together with a radon/thoron discriminative monitor that employs a silicon solid-state detector. The thoron sensitivity of the PIC detector was estimated by comparing the two detectors. As a result, the thoron sensitivity was about 10% compared with the radon sensitivity. In other words, the radon concentration (Bq m(-3)) measured with the PIC detector was approximately the sum of the actual radon concentration (Bq m(-3)) and 10% of the thoron concentration (Bq m(-3)). The sensitivity to thoron should be considered in measurements in thoron-enhanced areas. PMID:15103062

  15. Removal of the long-lived {sup 222}Rn daughters from steel and germanium surfaces

    SciTech Connect

    Wojcik, Marcin; Zuzel, Grzegorz; Majorovits, Bela

    2011-04-27

    Removal of the long-lived {sup 222}Rn daughters ({sup 210}Pb, {sup 210}Bi and {sup 210}Po) from stainless steel and germanium surfaces was investigated. As cleaning technique etching was applied to samples in a form of discs exposed earlier to a strong radon source. Reduction of the {sup 210}Pb activity was tested using a HPGe spectrometer, for {sup 210}Bi a beta spectrometer and for {sup 210}Po an alpha spectrometer was used. According to the conducted measurements all the isotopes were removed very efficiently from germanium. Results obtained for stainless steel were worse but still better than those achieved for copper.

  16. Application of thoron interference as a tool for simultaneous measurement of radon and thoron with a pulse ionisation chamber.

    PubMed

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

    2013-07-01

    Pulse ionisation chamber (PIC)-based monitors measuring radioactive gas radon ((222)Rn) without energy discrimination will have interference due to thoron ((220)Rn) present in the atmosphere. A technique has been developed to use this property of interference for simultaneous measurement of radon and thoron gas. These monitors work on the principle of counting of gross alphas emitted from radon and its progeny. A theoretical model has been developed for the variation of thoron sensitivity with respect to the flow rate of gas through the monitor. The thoron sensitivity of the monitor is found to vary with the flow rate of gas through the monitor. Using this sensitivity, the sampling procedure has been developed and verified for simultaneous measurement of radon and thoron. The PIC-measured radon and thoron concentration using this procedure agrees well with those measured by using standard radon and thoron discriminating monitor.

  17. Some recent studies on groundwater radon content as an earthquake precursor

    SciTech Connect

    Teng, T.

    1980-06-10

    Some recent studies of groundwater radon content in relation to seismic activities are reviewed. Results from China and Japan are presented, including laboratory experients and the development of continuous groundwater radon monitoring systems. In addition, groundwater radon monitoring studies conducted at the University of Southern California (USC) since 1974 are presented in some detail. The USC project includes a groundwater radon monitoring network of 14 sampling sites at cold springs, hot springs, deep irrigation wells, and artesian wells that are distributed along a 'locked' stretch of the San Andreas fault from Gorman to San Bernardino in California. Radon contents in weekly samples from these sites are analyzed to the precision of a few percent. No moderate-to-large earthquake has yet occurred in the vicinity, and the results show no clear association of radon anomalies with small (Mapprox.3) earthquakes to provide better test conditions. In contrast to earlier reports from Russia showing a long-term buildup of radon emission before earthquake occurrence, several recent reports from China and Japan show that groundwater radon anomalies can be short in duration and occur only within a few days before the main shocks. Observation of such effects are made possible with the use of continuous monitoring systems. In general, available data suggest that groundwater radon monitoring could sometimes yield precursor information. However, criteria have yet to be established by which sampling sites and sampling frequencies are selected.

  18. Influence of the mother's reproductive state on the hormonal status of daughters in marmosets (Callithrix kuhlii).

    PubMed

    Puffer, Alyssa M; Fite, Jeffrey E; French, Jeffrey A; Rukstalis, Michael; Hopkins, Elizabeth C; Patera, Kimberly J

    2004-09-01

    Behavioral and endocrine suppression of reproduction in subordinate females produces the high reproductive skew that characterizes callitrichid primate mating systems. Snowdon et al. [American Journal of Primatology 31:11-21, 1993] reported that the eldest daughters in tamarin families exhibit further endocrinological suppression immediately following the birth of siblings, and suggested that dominant females exert greater control over subordinate endocrinology during this energetically challenging phase of reproduction. We monitored the endocrine status of five Wied's black tufted-ear marmoset daughters before and after their mother delivered infants by measuring concentrations of urinary estradiol (E(2)), pregnanediol glucuronide (PdG), testosterone (T), and cortisol (CORT). Samples were collected from marmoset daughters 4 weeks prior to and 9 weeks following three consecutive sibling-litter births when the daughters were prepubertal (M=6.1 months of age), peripubertal (M=11.9 months), and postpubertal (M=17.6 months). The birth of infants was associated with reduced ovarian steroid excretion only in the prepubertal daughters. In contrast, ovarian steroid levels tended to increase in the postpubertal daughters. Urinary E(2) and T levels in the postpubertal daughters were 73.8% and 37.6% higher, respectively, in the 3 weeks following the birth of infants, relative to prepartum levels. In addition, peak urinary PdG concentrations in peri- and postpubertal daughters were equivalent to luteal phase concentrations in nonpregnant, breeding adult females, and all of the peri- and postpubertal daughters showed clear ovulatory cycles. Cortisol excretion did not change in response to the reproductive status of the mother, nor did the concentrations change across age. Our data suggest that marmoset daughters of potential breeding age are not hormonally suppressed during the mother's peripartum period or her return to fertility. These findings provide an additional example

  19. Mineral dusts and radon in uranium mines

    SciTech Connect

    Abelson, P.H.

    1991-11-08

    The Environmental Protection Agency (EPA) continues to assert that radon is a major cause of lung cancer in this country. EPA is fostering a radon program that could entail huge financial and emotional costs while yielding negligible benefits to public health. Justification for the program was the occurrence of lung cancer in men exposed to huge amounts of radon, mineral dusts, and other lung irritants in uranium mines on the Colorado Plateau. Lung cancer has been reported in about 356 cigarette smokers and in about 25 nonsmokers. During the era of high radon levels, monitoring was sporadic. Conditions in only a small fraction of the mines were measured, and that on a few separate occasions. Later, cumulative exposure to radon was calculated on the basis of measurements involving only a tiny fraction of the miners. Some were exposed to more than 15,000 pCi/liter of radon and its products. The level in the average home is about 1.5 pCi/liter. In making extrapolations from mine to home, the assumption is made that residents are in their dwellings most of the time and that miners spend only 170 hours a month in the mine. Two major questionable assumptions are involved in extrapolations from high doses of radon in the mines to low doses in homes. One is that no threshold is involved; that is, that humans have no remediation mechanism for {alpha} particle damages. There is evidence to the contrary. The most unrealistic assumption is that heavy exposure to silica has no effect on inducing lung cancer. Many studies have shown that silica dust causes lung cancer in animals. Exposure of human culture cells to silica has resulted in formation of neoplastic tissue. EPA has no solid evidence that exposures to 4 pCi/liter of radon causes lung cancer in either smokers or nonsmokers. Indeed, there is abundant evidence to the contrary in the fact that in states with high levels of radon, inhabitants have less lung cancer than those in states with low levels.

  20. Mother-Daughter Communication Patterns Re Sexuality.

    ERIC Educational Resources Information Center

    Fox, Greer L.

    After a review of the literature on teenage sexual behavior and contraceptive practice and their consequences, this paper presents a brief description of a research project on mother-daughter communication patterns, which is intended to investigate the influence of female parents on the sexual and contraceptive behavior of teenage daughters. It…

  1. Analysis of volatile phase transport in soils using natural radon gas as a tracer

    SciTech Connect

    Chen, C.; Thomas, D.M.

    1992-12-31

    We have conducted a field study of soil gas transport processes using radon gas as a naturally occurring tracer. The .experiment monitored soil gas radon activity, soil moisture, and soil temperature at three depths in the shallow soil column; barometric pressure, rainfall and wind speed were monitored at the soil surface. Linear and multiple regression analysis of the data sets has shown that the gas phase radon activities under natural environmental conditions are influenced by soil moisture content, barometric pressure variations, soil temperature and soil structure. The effect of wind speed on subsurface radon activities under our field conditions has not been demonstrated.

  2. Analysis of volatile phase transport in soils using natural radon gas as a tracer

    SciTech Connect

    Chen, C.; Thomas, D.M.

    1992-01-01

    We have conducted a field study of soil gas transport processes using radon gas as a naturally occurring tracer. The .experiment monitored soil gas radon activity, soil moisture, and soil temperature at three depths in the shallow soil column; barometric pressure, rainfall and wind speed were monitored at the soil surface. Linear and multiple regression analysis of the data sets has shown that the gas phase radon activities under natural environmental conditions are influenced by soil moisture content, barometric pressure variations, soil temperature and soil structure. The effect of wind speed on subsurface radon activities under our field conditions has not been demonstrated.

  3. 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.

  4. Is radon a causative factor in inducing myeloid leukemia and other cancers in adults and children?

    SciTech Connect

    Henshaw, D.L.; Eatough, J.P.; Richardson, R.B.

    1992-12-31

    In this paper we review our recent evidence linking domestic radon exposure with the incidence of certain cancers other than those in the lung. In the cases of leukemia and cancers of the skin, the review is supported by summarizing new calculations of the radon-derived dose to the target tissues. These show, for instance, that at the United Kingdom radon action limit of 200 Bq m{sup {minus}3}, the dose to red bone marrow from radon exceeds all other sources of background radiation. Data on the plate out of radon daughters suggests that doses to the basal layer beneath the skin can be sizable. Recent epidemiological data have shown a correlation of domestic radon exposure with several conditions, including leukemia in adults and children, and kidney cancer, melanoma, and prostatic cancer in adults. For leukemia, both acute myeloid (AML) and acute lymphatic leukemia (ALL) are associated with radon exposure; the latter is most often an effect in children. The associations appear both in international data and within certain countries, notably the United Kingdom. These observations, if assumed to be indicative of cause and effect, appear to contradict conventional risk estimates. However, the latter are based on a number of assumptions. In particular, there is indirect evidence that at low doses the RBE for the alpha particle is much higher than the currently recommended quality factor of 20. There is also evidence that a simple scaling of risk from acute to chronic exposures based on total dose may not be appropriate.

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

    PubMed

    Guo, Qiuju; Zhang, Lei; Guo, Lu

    2012-12-01

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

  6. Radon Measurements at the Molten Salt Reactor Experiment (MSRE) Facility from August 1997 through April 1998

    SciTech Connect

    Coleman, R.L.

    1999-04-01

    From August 1997 through April 1998, radon and radon progeny measurements were collected at the Molten Salt Reactor Experiment (MSRE) facility at Oak Ridge National Laboratory. The purpose of the measurements was to determine the baseline concentrations of 222Rn (radon), 220Rn (thoron), and their progeny in the air at selected points with emphasis on the characterization of 220Rn and its daughter products in the high bay area. The daughter product concentrations ranged from the equivalent of approximately 0.001 times the derived air concentration (DAC) of the isotope mixture up to 0.09 DAC, with the highest measurements occurring inside the pit above the equipment drain tank cell. Direct radon measurements in this area indicated a relatively constant 222Rn concentration with an average value of 1.4 pCi/L and a 220Rn concentration that fluctuated from <1 pCi/L up to about 30 pCi/L. Measurements were also collected inside the vent house adjacent to building 7503. The progeny concentrations inside the room ranged from an equivalent of about 0.002 DAC up to 0.01 DAC. The direct radon measurements in the vent house indicated a relatively constant 222Rn concentration with an average value of 0.7 pCi/L while the 220Rn concentration varied appreciably and ranged from <0.5 pCi/L up to almost 200 pCi/L with an average concentration of 18 pCi/L.

  7. Radon flux measurements on Gardinier and Royster phosphogypsum piles near Tampa and Mulberry, Florida

    SciTech Connect

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

    1986-01-01

    As part of the planned Environmental Protection Agency (EPA) radon flux monitoring program for the Florida phosphogypsum piles, Pacific Northwest Laboratory (PNL), under contract to the EPA, constructed 50 large-area passive radon collection devices and demonstrated their use at two phosphogypsum piles near Tampa and Mulberry, Florida. The passive devices were also compared to the PNL large-area flow-through system. The main objectives of the field tests were to demonstrate the use of the large-area passive radon collection devices to EPA and PEI personnel and to determine the number of radon flux measurement locations needed to estimate the average radon flux from a phosphogypsum pile. This report presents the results of the field test, provides recommendations for long-term monitoring, and includes a procedure for making the radon flux measurements.

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

    SciTech Connect

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

    1995-08-01

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

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

    SciTech Connect

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

    1996-02-01

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

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed

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

    2014-10-27

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

  12. Liquid xenon purification, de-radonation (and de-kryptonation)

    SciTech Connect

    Pocar, Andrea

    2015-08-17

    Liquid xenon detectors are at the forefront of rare event physics, including searches for neutrino-less double beta decay and WIMP dark matter. The xenon for these experiments needs to be purified from chemical impurities such as electronegative atoms and molecules, which absorb ionization electrons, and VUV (178 nm) scintillation light-absorbing chemical species. In addition, superb purification from radioactive impurities is required. Particularly challenging are radioactive noble isotopes ({sup 85}Kr,{sup 39,42}Ar,{sup 220,222}Rn). Radon is a particularly universal problem, due to the extended decay sequence of its daughters and its ubiquitous presence in detector materials. Purification and de-radonation of liquid xenon are addressed with particular focus on the experience gained with the EXO-200 neutrino-less double beta decay detector.

  13. Radon remediation of a two-storey UK dwelling by active sub-slab depressurisation: effects and health implications of radon concentration distributions.

    PubMed

    Allison, C C; Denman, A R; Groves-Kirkby, C J; Phillips, P S; Tornberg, R

    2008-10-01

    Radon concentration levels in a two-storey detached single-family dwelling in Northamptonshire, UK, were monitored continuously throughout a 5-week period during which active sub-slab depressurisation remediation measures were installed. Remediation of the property was accomplished successfully, with both the mean radon levels and the diurnal variability greatly reduced both upstairs and downstairs. Following remediation, upstairs and downstairs radon concentrations were 33% and 18% of their pre-remediation values respectively: the mean downstairs radon concentration was lower than that upstairs, with pre- and post-remediation values of the upstairs/downstairs concentration ratio, R(U/D), of 0.81 and 1.51 respectively. Cross-correlation between upstairs and downstairs radon concentration time-series indicates a time-lag of the order of 1 h or less, suggesting that diffusion of soil-derived radon from downstairs to upstairs either occurs within that time frame or forms a relatively insignificant contribution to the upstairs radon level. Cross-correlation between radon concentration time-series and the corresponding time-series for local atmospheric parameters demonstrated correlation between radon concentrations and internal/external pressure difference prior to remediation; this correlation disappears following remediation. Overall, these observations provide further evidence that radon concentration levels within a dwelling are not necessarily wholly determined by the effects of soil-gas advection, and further support the suggestion that, depending on the precise content of the building materials, upstairs radon levels, in particular, may be dominated by radon exhalation from the walls of the dwelling, especially in areas of low soil-gas radon.

  14. Study of a cave's air exchange pattern based on radon concentration and the time dependence of radon concentration in Pál-völgy Cave (Budapest, Hungary)

    NASA Astrophysics Data System (ADS)

    Nagy, H. E.; Horvath, A.; Jordan, Gy.; Szabo, Cs.; Kiss, A.

    2012-04-01

    A long-term (one year and a half), high resolution, with an integration time of one hour, radon concentration monitoring was carried out in Pál-völgy Cave (Budapest, Hungary). Our major goal was to determine the time dependence of radon concentration in the cave and to understand the exchange pattern of the cave air with the outdoor air based on radon concentrations, and to determine the factors that affect the radon concentration in the cave air. Pál-völgy Cave is situated in the Buda Hills, which is the NE part of the Transdanubian Central Range. The wall rock of the cave is dominantly Eocene Szépvölgy Limestone Formation. Above the limestone Eocene Buda Marl and Oligocene Tard Clay are deposited. A huge multiphase hydrothermal cave system developed in the Szépvölgy Limestone and partially in the Buda Marl resulted in a long-term complex paleokarstic evolution from the Late Eocene to the Quaternary. The radon concentration in the cave air was measured continuously by an AlphaGuard radon monitor, and meteorological parameters outside the cave were also collected simultaneously. The arithmetic mean of the annual radon concentration was 1.9 kBq/m3 and the radon concentration varied between 104-7,776 Bq/m3. In addition, the results indicate a clear seasonal variability of radon concentration in the cave air: in winter the radon concentration fluctuates around a low mean value of 253 Bq/m3, in summer it oscillates around a high mean value of 5,504 Bq/m3, whereas in spring and autumn the radon level varies between the winter and summer values. The summer to winter radon concentration ratio (radon concentration in summer/radon concentration in winter) was high, 21.8. The outside air temperature showed the strongest correlation with the radon concentration in the cave, Pierson's linear correlation coefficient is 0.76. If the outdoor air temperature is lower than the cave air temperature (12 °C), especially in autumn and winter the air flows from outside into the

  15. Radon measurements at the FEMP

    SciTech Connect

    Tomczak, L.M.; Daniels, R.D.; Dennis, C.; Glassey, H.G.; Lohner, W.G.; Ray, E.C.; Selasky, J.A.; Spitz, H.B.; Roush, K.

    1993-08-01

    Environmental radon monitoring activities at the DOE Fernald Environmental Management Project (FEMP) have been conducted extensively since the early 1980`s. Monitoring has been conducted at ambient concentration levels (< 1 pCi/L Rn-222), inside buildings, and at significantly elevated levels (hundreds of thousands pCi/L Rn-222) within the K-65 silo that store concentrated radium bearing wastes. The purpose of this paper/presentation is to present and discuss some of the difficulties encountered/solutions (e.g. reliability, detection limits, affects of environmental factors, data transfer, etc.) that have been discovered while taking measurements using both alpha track-etch passive integrating detectors and alpha scintillation real-time detectors. A short summary and conclusion section is provided following each topic presented.

  16. Environmental radon and cancer correlations in Maine.

    PubMed

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

    1983-08-01

    The distribution of 222Rn has been measured in the sixteen counties of Maine, U.S.A. by liquid scintillation counting of water samples from more than two thousand public and private wells. Three hundred and fifty of these wells have been characterized for geology and hydrology. Airborne radon has been measured in seventy houses with grab samples and in eighteen houses for 5-7 days each with continuously recording diffusion-electrostatic radon detectors. Concentrations of radon in water ranged from 20 to 180,000 pCi/l. Granite areas yielded the highest average levels (mean = 22,100 pCi/l.; n = 136), with considerable intra-granite variation. Metasedimentary rocks yielded levels characteristic of the lithology for metamorphic grades ranging from chlorite to andalusite. Sillimanite and higher-grade rocks yielded higher 222Rn levels, probably due to the intrusion of uranium-bearing pegmatites in these terranes. Airborne 222Rn in homes ranged from 0.05 to 210 pCi/l. At the high end of this range, doses will exceed recommended industrial limits. In some homes only a small fraction of the airborne 222Rn was due to the water supply. Average 222Rn levels in domestic water supplies for each of the 16 counties, calculated by areally averaging rock types and their associated 222Rn levels, were found to be significantly correlated with rates for all cancers combined and rates for lung and reproductive cancers in the counties. Although numerous factors other than cancer induction by indoor daughter exposures may be responsible for the observed correlations, these have not been investigated in detail. PMID:6885433

  17. Environmental radon and cancer correlations in Maine.

    PubMed

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

    1983-08-01

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

  18. Measuring radon exhalation rate in two cycles avoiding the effects of back-diffusion and chamber leakage.

    PubMed

    Tan, Yanliang; Xiao, Detao

    2013-10-01

    This paper will present a simple method for measuring the radon exhalation rate from the medium surface in two cycles and also avoiding the effects of back-diffusion and chamber leakage. The method is based on a combination of the "accumulation chamber" technique and a radon monitor. The radon monitor performs the measurement of the radon concentration inside the accumulation chamber, and then the radon exhalation rate can be obtained by simple calculation. For reducing the systematic error and the statistical uncertainty, too short of total measurement time is not appropriate, and the first cycle time should be about 70 % of the total measurement. The radon exhalation rate from the medium surface obtained through this method is in good agreement with the reference value. This simple method can be applied to develop and improve the instruments for measuring radon exhalation rate.

  19. Measurement and modeling of radon infiltration into a test dwelling

    SciTech Connect

    Stoop, P.; Meijer, R.J. de; Put, L.W.

    1992-12-31

    To understand radon transport in Dutch residences, we made a detailed study of its characteristics in a test house. Information on the dynamic aspects of radon transport was obtained from leakage parameters and from continuously monitoring the concentration in the dwelling and crawl space and the pressure differences between compartments. Concentrations and dynamic variables were used as input for a multicompartment model to derive the radon production rate for the two components. Depressurization and pressurization of the crawl space led to substantial changes in the radon concentration in the crawl space but had less effect in the living room. The results suggest that pressure-driven flow of radon through the soil is an important source for radon in the crawl space. The production rate for the dwelling cannot be explained in terms of known exhalation rates and known air flows; therefore the remainder, which appeared to be pressure-dependent, might be due to radon-rich air entering the dwelling via the cavity wall.

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

    PubMed

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

    2009-11-01

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

  1. Standardised Radon Index (SRI): a normalisation of radon data-sets in terms of standard normal variables

    NASA Astrophysics Data System (ADS)

    Crockett, R. G. M.; Holt, C. P.

    2011-07-01

    During the second half of 2002, from late June to mid December, the University of Northampton Radon Research Group operated two continuous hourly-sampling radon detectors 2.25 km apart in the English East Midlands. This period included the Dudley earthquake (ML = 5, 22 September 2002) and also a smaller earthquake in the English Channel (ML = 3, 26 August 2002). Rolling/sliding windowed cross-correlation of the paired radon time-series revealed periods of simultaneous similar radon anomalies which occurred at the time of these earthquakes but at no other times during the overall radon monitoring period. Standardising the radon data in terms of probability of magnitude, analogous to the Standardised Precipitation Indices (SPIs) used in drought modelling, which effectively equalises different non-linear responses, reveals that the dissimilar relative magnitudes of the anomalies are in fact closely equiprobabilistic. Such methods could help in identifying anomalous signals in radon - and other - time-series and in evaluating their statistical significance in terms of earthquake precursory behaviour.

  2. 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.

  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. PMID:25920786

  4. Preliminary radon measurements at Villarrica volcano, Chile

    NASA Astrophysics Data System (ADS)

    Cigolini, C.; Laiolo, M.; Coppola, D.; Ulivieri, G.

    2013-10-01

    We report data from a radon survey conducted at Villarrica volcano. Measurements have been obtained at selected sites by E-PERM® electrets and two automatic stations utilizing DOSEman detectors (SARAD Gmbh). Mean values for Villarrica are 1600 (±1150) Bq/m3 are similar to values recorded at Cerro Negro and Arenal in Central America. Moderately higher emissions, at measurement sites, were recorded on the NNW sector of the volcano and the summit, ranging from 1800 to 2400 Bq/m3. These measurements indicate that this area could potentially be a zone of flank weakness. In addition, the highest radon activities, up to 4600 Bq/m3, were measured at a station located near the intersection of the Liquiñe-Ofqui Fault Zone with the Gastre Fault Zone. To date, the Villarrica radon measurements reported here are, together with those collected at Galeras (Colombia), the sole radon data reported from South American volcanoes. This research may contribute to improving future geochemical monitoring and volcano surveillance.

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

    PubMed

    Alharbi, Sami H; Akber, Riaz A

    2015-06-01

    Radon and thoron are radioactive gases that can emanate from soil and building materials, and it can accumulate in indoor environments. The concentrations of radon and thoron in the air from various workplace categories in Brisbane, Australia were measured using an active method. The average radon and thoron concentrations for all workplace categories were 10.5 ± 11.3 and 8.2 ± 1.4 Bq m(-3), respectively. The highest radon concentration was detected in a confined area, 86.6 ± 6.0 Bq m(-3), while the maximum thoron level was found in a storage room, 78.1 ± 14.0 Bq m(-3). At each site, the concentrations of radon and thoron were measured at two heights, 5 cm and 120 cm above the floor. The effect of the measurement heights on the concentration level was significant in the case of thoron. The monitoring of radon and thoron concentrations showed a lower radon concentration during work hours than at other times of the day. This can be attributed to the ventilation systems, including the air conditioner and natural ventilation, which normally operate during work hours. The diurnal variation was less observed in the case of thoron, as the change in its concentration during and after the working hours was insignificant. The study also investigated the influence of the floor level and flooring type on indoor radon and thoron concentrations. The elevated levels of radon and thoron were largely found in basements and ground floor levels and in rooms with concrete flooring. PMID:25827573

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

    PubMed

    Alharbi, Sami H; Akber, Riaz A

    2015-06-01

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

  7. Towards a Brazilian radon map: consortium radon Brazil.

    PubMed

    Silva, N C; Bossew, P; Ferreira Filho, A L; Campos, T F C; Pereira, A J S C; Yoshimura, E M; Veiga, L H S; Campos, M P; Rocha, Z; Paschuk, S A; Bonotto, D M

    2014-07-01

    Recently, the idea of generating radon map of Brazil has emerged. First attempts of coordinating radon surveys--carried out by different groups across the country--and initial discussions on how to proceed on a larger scale were made at the First Brazilian Radon Seminary, Natal, September 2012. Conventionally, it is believed that indoor radon is no major problem in Brazil, because the overall benign climate usually allows high ventilation rates. Nevertheless, scattered measurements have shown that moderately high indoor radon concentrations (up to a few hundred Bq m⁻³) do occur regionally. Brazilian geology is very diverse and there are regions where an elevated geogenic radon potential exists or is expected to exist. Therefore, a Brazilian Radon Survey is expected to be a challenge, although it appears an important issue, given the rising concern of the public about the quality of its environment.

  8. On radon emanation as a possible indicator of crustal deformation

    USGS Publications Warehouse

    King, C.-Y.

    1979-01-01

    Radon emanation has been monitored in shallow capped holes by a Tracketch method along several active faults and in the vicinity of some volcanoes and underground nuclear explosions. The measured emanation shows large temporal variations that appear to be partly related to crustal strain changes. This paper proposes a model that may explain the observed tectonic variations in radon emanation, and explores the possibility of using radon emanation as an indicator of crustal deformation. In this model the emanation variation is assumed to be due to the perturbation of near-surface profile of radon concentration in the soil gas caused by a change in the vertical flow rate of the soil gas which, in turn, is caused by the crustal deformation. It is shown that, for a typical soil, a small change in the flow rate (3 ?? 10-4 cm sec-1) can effect a significant change (a factor of 2) in radon emanation detected at a fixed shallow depth (0.7 m). The radon concentration profile has been monitored at several depths at a selected site to test the model. The results appear to be in satisfactory agreement. ?? 1979.

  9. Estimation of radon concentrations in coal mines using a hybrid technique calibration curve.

    PubMed

    Jamil, K; Ali, S

    2001-01-01

    The results of epidemiological studies in various countries show that radon and its progeny cause carcinogenic effects on mine workers. Therefore, it becomes of paramount importance to monitor radon concentrations and consequently determine the radon dose rates in coal mines for the protection of coal miners. A new calibration curve was obtained for radon concentration estimation using hybrid techniques. A calibration curve was generated using 226Ra activity concentration measured by a HPGe detector-based gamma-ray spectrometer versus alpha-track-density rate due to radon and its progeny on CR-39 track detector. Using the slope of the experimentally determined curve in the units of Becqueral per kilogram (Bq kg-1) per unit alpha-track-density per hour (cm-2 h-1), radon concentrations (Bq m-3) were estimated using coal samples from various coal mines in two provinces of Pakistan, Punjab and Balochistan. Consequently, radon dose rates were computed in the simulated environment of the coal mines. Results of these computations may be considered with a caveat that the method developed in this paper provides only a screening method to indicate the radon dose in coal mines. It has been shown that the actual measurements of radon concentrations in the coal mines are in agreement with the estimated radon concentrations using the hybrid-technique calibration curve.

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

    SciTech Connect

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

    1992-12-31

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

  11. Radon releases from Australian uranium mining and milling projects: assessing the UNSCEAR approach.

    PubMed

    Mudd, Gavin M

    2008-02-01

    The release of radon gas and progeny from the mining and milling of uranium-bearing ores has long been recognised as a potential radiological health hazard. The standards for exposure to radon and progeny have decreased over time as the understanding of their health risk has improved. In recent years there has been debate on the long-term releases (10,000 years) of radon from uranium mining and milling sites, focusing on abandoned, operational and rehabilitated sites. The primary purpose has been estimates of the radiation exposure of both local and global populations. Although there has been an increasing number of radon release studies over recent years in the USA, Australia, Canada and elsewhere, a systematic evaluation of this work has yet to be published in the international literature. This paper presents a detailed compilation and analysis of Australian studies. In order to quantify radon sources, a review of data on uranium mining and milling wastes in Australia, as they influence radon releases, is presented. An extensive compilation of the available radon release data is then assembled for the various projects, including a comparison to predictions of radon behaviour where available. An analysis of cumulative radon releases is then developed and compared to the UNSCEAR approach. The implications for the various assessments of long-term releases of radon are discussed, including aspects such as the need for ongoing monitoring of rehabilitation at uranium mining and milling sites and life-cycle accounting.

  12. Measurements of radon concentrations in waters and soil gas of Zonguldak, Turkey.

    PubMed

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

    2014-12-01

    The radon concentrations in soil-gas and water samples (in the form of springs, catchment, tap, thermal) used as drinking water or thermal were measured using a professional radon monitor AlphaGUARD PQ 2000PRO. The measured radon concentrations in water samples ranged from 0.32 to 88.22 Bq l(-1). Most of radon levels in potable water samples are below the maximum contaminant level of 11 Bq l(-1) recommended by the US Environmental Protection Agency. The calculated annual effective doses due to radon intake through water consumption varied from 0.07 to 18.53 µSv y(-1). The radon concentrations in soil gas varied from 295.67 to 70 852.92 Bq m(-3). The radon level in soil gas was found to be higher in the area close to the formation boundary thrust and faults. No correlation was observed between radon concentrations in groundwater and soil gas. Also, no significant correlation was observed between soil-gas radon and temperature, pressure and humidity. The emanation of radon from groundwater and soil gas is controlled by the geological formation and by the tectonic structure of the area. PMID:24287600

  13. Radionuclide daughter inventory generator code: DIG

    SciTech Connect

    Fields, D.E.; Sharp, R.D.

    1985-09-01

    The Daughter Inventory Generator (DIG) code accepts a tabulation of radionuclide initially present in a waste stream, specified as amounts present either by mass or by activity, and produces a tabulation of radionuclides present after a user-specified elapsed time. This resultant radionuclide inventory characterizes wastes that have undergone daughter ingrowth during subsequent processes, such as leaching and transport, and includes daughter radionuclides that should be considered in these subsequent processes or for inclusion in a pollutant source term. Output of the DIG code also summarizes radionuclide decay constants. The DIG code was developed specifically to assist the user of the PRESTO-II methodology and code in preparing data sets and accounting for possible daughter ingrowth in wastes buried in shallow-land disposal areas. The DIG code is also useful in preparing data sets for the PRESTO-EPA code. Daughter ingrowth in buried radionuclides and in radionuclides that have been leached from the wastes and are undergoing hydrologic transport are considered, and the quantities of daughter radionuclide are calculated. Radionuclide decay constants generated by DIG and included in the DIG output are required in the PRESTO-II code input data set. The DIG accesses some subroutines written for use with the CRRIS system and accesses files containing radionuclide data compiled by D.C. Kocher. 11 refs.

  14. RADON reconstruction in longitudinal phase space

    SciTech Connect

    Mane, V.; Peggs, S.; Wei, J.

    1997-07-01

    Longitudinal particle motion in circular accelerators is typically monitoring by one dimensional (1-D) profiles. Adiabatic particle motion in two dimensional (2-D) phase space can be reconstructed with tomographic techniques, using 1-D profiles. A computer program RADON has been developed in C++ to process digitized mountain range data and perform the phase space reconstruction for the AGS, and later for Relativistic Heavy Ion Collider (RHIC).

  15. Radon: counseling patients about risk.

    PubMed

    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. PMID:2203238

  16. Radon gas: Health risks and toxicity. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-01-01

    The bibliography contains citations concerning health risks and toxicity associated with indoor and outdoor exposure to radon gas. Citations discuss radon sources from tobacco smoke, fossil fuel combustion, phosphate mining, uranium mining, granitic rocks, building materials, and water supplies. Discussed also are risk assessment, regulations, radon gas monitoring, exposure modeling and control, biological pathways, and occupational exposure. Radionuclides in groundwater, and radon analysis and detection, are examined in separate bibliographies. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  17. Radon gas: Health risks and toxicity. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    Not Available

    1994-01-01

    The bibliography contains citations concerning health risks and toxicity associated with indoor and outdoor exposure to radon gas. Citations discuss radon sources from tobacco smoke, fossil fuel combustion, phosphate mining, uranium mining, granitic rocks, building materials, and water supplies. Discussed also are risk assessment, regulations, radon gas monitoring, exposure modeling and control, biological pathways, and occupational exposure. Radionuclides in groundwater, and radon analysis and detection, are examined in separate bibliographies. (Contains a minimum of 130 citations and includes a subject term index and title list.)

  18. Radon Dose Determination for Cave Guides in Czech Republic

    SciTech Connect

    Thinova, Lenka; Rovenska, Katerina

    2008-08-07

    According to recommended approach there are six (from total of twelve) open-to-public caves in Czech Republic, reaching near to an effective lung-dose of 6mSv/year. A conservative approach for estimating the potential effective lung-dose in caves (or underground) is based on two season's measurements, using solid state alpha track detector (Kodak in plastic diffusion chamber). The obtained dataset is converted into an annual effective dose, in agreement with the ICRP65 recommendation, using the 'cave factor' 1.5. The value of 'cave factor' which depends on the spectrum of aerosol particles, or on the proportional representation of the unattached/attached ratio (6.5 : 93.5 for residential places, 13.6 : 86.4 for caves due to lower concentration of free aerosols) and on the equilibrium factor. Thus conversion factor is 1.5 times higher in comparison with ICRP 65. Is this correct? Because a more precisely determined dose value would have a significant impact on radon remedies, or on restricting the time workers stay underground, a series of measurement was initiated in 2003 with the aim to specify input data, computation and errors in effective dose assessment in each one of the evaluated caves separately. The enhancement of personal dosimetry for underground work places includes a study of the given questions, from the following points of view in each cave: continual radon measurement; regular measurements of radon and its daughters to estimate the equilibrium factor and the presence of free {sup 218}Po; regular indoor air flow measurements to study the location of the radon supply and its transfer among individual areas of the cave; natural radioactive element content evaluation in subsoil and in water inside/outside, a study of the radon sources in the cave; determination of the free fraction from continual unattached and attached fraction measurement (grid and filter); thoron measurement. Air flow measurements provide very interesting information about the origin

  19. Radon Dose Determination for Cave Guides in Czech Republic

    NASA Astrophysics Data System (ADS)

    Thinova, Lenka; Rovenska, Katerina

    2008-08-01

    According to recommended approach there are six (from total of twelve) open-to-public caves in Czech Republic, reaching near to an effective lung-dose of 6mSv/year. A conservative approach for estimating the potential effective lung-dose in caves (or underground) is based on two season's measurements, using solid state alpha track detector (Kodak in plastic diffusion chamber). The obtained dataset is converted into an annual effective dose, in agreement with the ICRP65 recommendation, using the "cave factor" 1.5. The value of "cave factor" which depends on the spectrum of aerosol particles, or on the proportional representation of the unattached/attached ratio (6.5 : 93.5 for residential places, 13.6 : 86.4 for caves due to lower concentration of free aerosols) and on the equilibrium factor. Thus conversion factor is 1.5 times higher in comparison with ICRP 65. Is this correct? Because a more precisely determined dose value would have a significant impact on radon remedies, or on restricting the time workers stay underground, a series of measurement was initiated in 2003 with the aim to specify input data, computation and errors in effective dose assessment in each one of the evaluated caves separately. The enhancement of personal dosimetry for underground work places includes a study of the given questions, from the following points of view in each cave: continual radon measurement; regular measurements of radon and its daughters to estimate the equilibrium factor and the presence of free 218Po; regular indoor air flow measurements to study the location of the radon supply and its transfer among individual areas of the cave; natural radioactive element content evaluation in subsoil and in water inside/outside, a study of the radon sources in the cave; determination of the free fraction from continual unattached and attached fraction measurement (grid and filter); thoron measurement. Air flow measurements provide very interesting information about the origin of

  20. Radon Research Program, FY 1991

    SciTech Connect

    Not Available

    1992-03-01

    The scientific information being sought in this program encompasses research designed to determine radon availability and transport outdoors, modeling transport into and within buildings, physics and chemistry of radon and radon progeny, dose response relationships, lung cancer risk, and mechanisms of radon carcinogenesis. The main goal of the DOE/OHER Radon Research Program is to develop information to reduce these uncertainties and thereby provide an improved health risk estimate of exposure to radon and its progeny as well as to provide information useful in radon control strategies. Results generated under the Program were highlighted in a National Research Council report on radon dosimetry. The study concluded that the risk of radon exposure is 30% less in homes than in mines. This program summary of book describes the OHER FY-1991 Radon Research Program. It is the fifth in an annual series of program books designed to provide scientific and research information to the public and to other government agencies on the DOE Radon Research Program.

  1. 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. PMID:21498864

  2. IDENTIFICATION OF CANDIDATE HOUSES FOR NORTH FLORIDA PORTION OF THE FLORIDA RADON MITIGATION PROJECT

    EPA Science Inventory

    The report gives results of a study to locate candidate houses for a proposed radon mitigation research and demonstration project in North Florida. he effort involved: 1) identification of target geographical areas, 2) radon monitoring in identified clusters, and 3) house charact...

  3. Quality assurance for radon exposure chambers at the National Air and Radiation Environmental Laboratory, Montgomery, Alabama

    SciTech Connect

    Semler, M.O.; Sensintaffar, E.L.

    1993-12-31

    The Office of Radiation and Indoor Air, U.S. Environmental Protection Agency (EPA), operates six radon exposure chambers in its two laboratories, the National Air and Radiation Environmental Laboratory (NAREL) in Montgomery, Alabama, and the Las Vegas Facility, Las Vegas, Nevada. These radon exposure chambers are used to calibrate and test portable radon measuring instruments, test commercial suppliers of radon measurement services through the Radon Measurement Proficiency Program, and expose passive measurement devices to known radon concentrations as part of a quality assurance plan for federal and state studies measuring indoor radon concentrations. Both laboratories participate in national and international intercomparisons for the measurement of radon and are presently working with the National Institute of Standards and Technology (NIST) to receive a certificate of traceability for radon measurements. NAREL has developed an estimate of the total error in its calibration of each chamber`s continuous monitors as part of an internal quality assurance program. This paper discusses the continuous monitors and their calibration for the three chambers located in Montgomery, Alabama, as well as the results of the authors intercomparisons and total error analysis.

  4. 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)

  5. Radon exposure assessment in a former uranium production facility

    SciTech Connect

    Akbar-Khanzadch, F.; Merrill, E.A.

    1996-06-01

    Storage of radon-producing materials in three silos and six waste pits is one of the major environmental and occupational issues at a former uranium production facility, now a Superfund Site. The concentrations of radium up to 190,000 pCi g{sup -1} for silos and up to 1,200 pCi g{sup -1} for waste pits have been reported. This study was conducted to identify conditions and climatic factors that contribute to higher radon levels and to assess workers` exposure at the site. Data covering a 12-mo period were compiled from monitoring radon levels by hourly real-time indoor (within 3 buildings) and outdoor (at 14 on-site and 2 off-site stations) and from hourly site specific meteorological information. The ranges of radon levels were 0.05-98.8 pCi L{sup -1} outdoor on-site, 0.1-8.9 pCi L{sup -1} outdoor off-side, and 0.05-3.0 pCi L{sup -1} indoor on-site. Only radon levels in the vicinity of the storage silos, which is an exclusion zone, were significantly higher than levels off-site. Significantly higher levels of radon were detected in the production areas vs. those at the perimeter areas, suggesting that there were significant sources of on-site radon contamination other than the silos. Radon concentrations showed diurnal variations, maximum levels occurring at early morning and minimum levels in the afternoon. A seasonal variation was also observed, with radon levels highest during mid summer while lowest during winter. Wind direction, wind speed, relative humidity, and ambient temperature appeared to be the most significant predictors of radon concentration. The dose, calculated by using exposure models and annual average levels of radon in the work area, was below recommended exposure limits. These results suggest that the emission control methods at this site have been effective in maintaining environmental radon contamination and workers` exposure at acceptable levels.

  6. Novel determination of radon-222 velocity in deep subsurface rocks, and the feasibility to using radon as an earthquake precursor

    NASA Astrophysics Data System (ADS)

    Zafrir, Hovav; Benhorin, Yochy; Malik, Uri; Chemo, Chaim

    2016-04-01

    An enhanced radon monitoring system was designed in order to study shallow versus deep subsurface processes affecting the appearance of radon anomalies. The method is based on the assumption that the climatic influence is limited since its energy decreases with the decrease in thickness of the geological cover whereby its effect is reduced to a negligible value at depth. Hence, lowering gamma and alpha detectors into deep boreholes and monitoring their temporal variations relative to a reference couple at shallow depths of 10-40 m eliminates the ambient thermal and pressure-induced contribution from the total radon time series. It allows highlighting the residual portion of the radon signals that might be associated with the geodynamic processes. The primary technological key is the higher sensitivity of the gamma detectors - in comparison to the solid-state alpha detectors, which are also suitable for threading into narrow boreholes in parallel to the narrow gamma detector (Zafrir et al., 2013*). The unique achievements of the novel system that was installed at the Sde Eliezer site close to the Hula Valley western border fault (HWBF) in northern Israel are: a) Determination, for the first time, of the radon movement velocity within rock layers at depths of several tens of meters, namely, 25 m per hour on average; b) Distinguishing between the diurnal periodical effect of the ambient temperature and the semi-diurnal effect of the ambient pressure on the radon temporal spectrum; c) Identification of a radon random pre-seismic anomaly preceding the Nuweiba, M 5.5 earthquake of 27 June 2015 that occurred within Dead Sea Fault Zone. * Zafrir, H., Barbosa, S.M. and Malik, U., 2013. Differentiation between the effect of temperature and pressure on radon within the subsurface geological media, Radiat. Meas., 49, 39-56. doi:10.1016/j.radmeas.2012.11.019.

  7. Potential lung cancer risk from indoor radon exposure

    SciTech Connect

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

    1990-09-01

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

  8. Constraints for Using Radon-in-Water Concentrations as an Indicator for Groundwater Discharge into Surface Water Bodies

    NASA Astrophysics Data System (ADS)

    Petermann, Eric; Schubert, Michael

    2015-04-01

    The radon (222-Rn) activity concentration of surface water is a favourable indicator for the detection of groundwater discharge into surface water bodies since radon is highly enriched in groundwater relative to surface waters. Hence, positive radon-in-water anomalies are interpreted as groundwater discharge locations. For this approach, usually, radon time-series are recorded along transects in near-surface waters. Time-series of radon-in-water concentration are commonly measured by permanent radon extraction from a water pump stream and continuous monitoring of the resulting radon-in-air concentration by means of a suitable radon detector. Radon-in-water concentrations are derived from the recorded radon-in-air signal by making allowances for water/air partitioning of radon. However, several constraints arise for this approach since undesirable factors are influencing the radon-in-water concentration. Consequently, corrections are required to remove the effect of these undesirable factors from the radon signal. First, an instrument inherent response delay between actual changes in the radon-in-water concentration and the related radon-in-air signal was observed during laboratory experiments. The response delay is due to (i) the water/air transfer kinetics of radon and (ii) the delayed decay equilibrium between radon and its progeny polonium (218-Po), which is actually being measured by most radon-in-air monitors. We developed a physical model, which considers all parameters that are responsible for the response delay. This model allows the reconstruction of radon-in-water time-series based on radon-in-air records. Second, on a time-scale of several hours the tidal stage is known as a major driver for groundwater discharge fluctuations due to varying hydraulic gradients between groundwater and surface water during a tidal cycle. Consequently, radon-in-water time-series that are detected on tidal coasts are not comparable among each other without normalization

  9. Observation of lunar radon emanation with the Apollo 15 alpha particle spectrometer.

    NASA Technical Reports Server (NTRS)

    Gorenstein, P.; Bjorkholm, P.

    1972-01-01

    The alpha particle spectrometer, a component of the orbital Sim Bay group of 'geochemistry' experiments on Apollo 15, was designed to detect alpha particles emitted during the decay of isotopes of radon gas and her daughter products. The purpose was to measure the gross activity of radon on the lunar surface and to find possible regions of increased local activity. Results are presented from a partial analysis of Apollo 15 data. For the moon as a whole, Rn220 was not observed and the upper limit on its decay rate above the lunar surface is 0.00038 disintegrations/sq cm-sec. Rn222 was marginally observed. Possible variations of radon activity on the lunar surface are being investigated. Po210 (a daughter product of Rn222) has been detected in a broad region from west of Mare Crisium to the Van de Graaff-Orlov region. The observed count rate is (4.6 plus or minus 1.4) x 0.001 disintegrations/sq cm-sec. The observed level of Po210 activity is in excess of the amount that would be in equilibrium with Rn222 by about an order of magnitude. This implies that larger levels of radon emanation have occurred on the moon within a time scale of 10 to 100 years.

  10. A creeping suspicion about radon

    SciTech Connect

    Alderson, L.

    1994-10-01

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

  11. Adult Daughters' Descriptions of Their Mother-Daughter Relationship in the Context of Chronic Conflict.

    PubMed

    Pickering, Carolyn E Z; Mentes, Janet C; Moon, Ailee; Pieters, Huibrie C; Phillips, Linda R

    2015-01-01

    The purpose of this article is to describe, from the perspective of the adult daughter, the mother-daughter relationship in the context of chronic conflict. Grounded theory methodology was used. An online recruitment strategy was used to identify a sample of adult daughters (N = 13) who self-identified as having an abusive relationship with their aging mother. Data collection was completed through semi-structured telephone interviews. Daughters framed their relationship around their perceptions of past childhood injustices. These injustices invoked strong negative emotions. Daughters had equally strong motivations for sustaining the relationship, driven by desire to reconcile their negative experience through seeking validation and futile-hoping as well as a sense of obligation to do due diligence. Together these factors created an environment of inevitable confrontation and a relationship defined by chronic conflict. Findings from the study provide theoretical insights to the conceptualization of aggression, power relationships, and the development of elder abuse and neglect. PMID:26421508

  12. Adult Daughters' Descriptions of Their Mother-Daughter Relationship in the Context of Chronic Conflict.

    PubMed

    Pickering, Carolyn E Z; Mentes, Janet C; Moon, Ailee; Pieters, Huibrie C; Phillips, Linda R

    2015-01-01

    The purpose of this article is to describe, from the perspective of the adult daughter, the mother-daughter relationship in the context of chronic conflict. Grounded theory methodology was used. An online recruitment strategy was used to identify a sample of adult daughters (N = 13) who self-identified as having an abusive relationship with their aging mother. Data collection was completed through semi-structured telephone interviews. Daughters framed their relationship around their perceptions of past childhood injustices. These injustices invoked strong negative emotions. Daughters had equally strong motivations for sustaining the relationship, driven by desire to reconcile their negative experience through seeking validation and futile-hoping as well as a sense of obligation to do due diligence. Together these factors created an environment of inevitable confrontation and a relationship defined by chronic conflict. Findings from the study provide theoretical insights to the conceptualization of aggression, power relationships, and the development of elder abuse and neglect.

  13. 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.

  14. 2014 ICHLNRRA intercomparison of radon/thoron gas and radon short-lived decay products measuring instruments in the NRPI Prague.

    PubMed

    Jílek, K; Timková, J

    2015-06-01

    During the Eighth International Conference on High Levels of Natural Radiation and Radon Areas held in autumn 2014 at Prague, the third intercomparison of radon/thoron gas and radon short-lived decay products measurement instruments was organised by and held at the Natural Radiation Division of the National Radiation Protection Institute (NRPI; SÚRO v.v.i.) in Prague. The intercomparison was newly focussed also on continuous monitors with active sampling adapters capable to distinguish radon/thoron gas in their mix field.The results of radon gas measurements carried out in the big NRPI radon chamber indicated very well an average deviation of up to 5 % from the reference NRPI value for 80 % of all the exposed instruments. The results of equilibrium equivalent concentration continuous monitors indicated an average deviation of up to 5 % from the reference NRPI value for 40 % of all the exposed instruments and their ~8-10 % shift compared with the NRPI. The results of investigated ambient conditions upon response of exposed continuous monitors indicated influence of aerosol changes upon response of radon monitors with an active air sampling adapters through the filter, only. The exposures of both radon/thoron gas discriminative continuous monitors and passive detectors have been indicated inconsistent results: on one hand, their excellent agreement up to several per cent for both the gases, and on the other hand, systematic unsatisfactory differences up to 40 %. Additional radon/thoron exercises are recommended to improve both the instruments themselves and quality of their operators.

  15. 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...

  16. Proceedings of the technical exchange meeting on passive radon monnitoring

    SciTech Connect

    Duray, J.R.; Langner, H. Jr.; Martz, D.E.

    1987-09-01

    The purpose of the meeting was to bring together a number of scientists active in the development and use of passive radon monitoring instrumentation, primarily activated charcoal detectors and alpha track detectors. Many of those present expressed a desire to receive copies of the viewgraphs and other materials presented. Most have supplied extended abstracts or complete reports. These materials are reproduced here as a Technical Measurements Center Report for the benefit of those attending the meeting and for others interested in passive radon monitoring. Individual papers were processed separately for the data base.

  17. Radon concentrations in three underground lignite mines in Turkey.

    PubMed

    Cile, S; Altinsoy, N; Celebi, N

    2010-01-01

    Monitoring of radon in underground mines is important in order to assess the radiological hazards to occupational workers. Radon concentration levels in three underground lignite mines (Tunçbilek, Omerler and Eynez) of Turkey were obtained in this study. For this reason, atmospheric radon level measurements were carried out in mines using CR-39 track detectors. Chemical etching of the detector tracks and subsequent counting were performed at Cekmece Nuclear Research and Training Center. The obtained results were evaluated according to the International Commission of Radiation Protection and the Turkish Atomic Energy Authority whose radon action levels for workplaces are 500-1500 and 1000 Bq(-3), respectively. The radon gas concentrations in the lignite mines were determined to be between 50 +/- 7 and 587 +/- 16 Bq m(-3). The results obtained in these experiments are far under the action levels. The computed radon doses for the mine workers of Tunçbilek, Omerler and Eynez lignite mines are 1.23, 2.44 and 1.47 mSv y(-1), respectively.

  18. Radon mapping - Santa Barbara and Ventura counties

    SciTech Connect

    Churchill, R.

    1997-11-01

    Since 1990, the Department of Conservation`s Division of Mines and Geology (DMG) has provided geologic information and conducted several research projects on geology and radon for the California Department of Health Services (DHS) Radon Program. This article provides a brief overview of radon`s occurrence and impact on human health, and summarizes a recent DMG project for DHS that used geologic, geochemical, and indoor radon measurement data to produce detailed radon potential zone maps for Santa Barbara and Ventura counties.

  19. 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.

  20. 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.

  1. 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.

  2. Radon Research Program, FY 1992

    SciTech Connect

    Not Available

    1993-04-01

    The United States Department of Energy, Office of Health and Environmental Research (DOE/OHER) is the principal federal agency conducting basic research related to indoor radon. The scientific information being sought in this program encompasses research designed to determine radon availability and transport outdoors, modeling transport into and within buildings, physics and chemistry of radon and radon progeny, dose response relationships, lung cancer risk, and mechanisms of radon carcinogenesis. There still remains a significant number of uncertainties in the currently available knowledge that is used to estimate lung cancer risk from exposure to environmental levels of radon and its progeny. The main goal of the DOE/OHER Radon Research Program is to develop information to reduce these uncertainties and thereby provide an improved health risk estimate of exposure to radon and its progeny and to identify and understand biological mechanisms of lung cancer development and required copollutants at low levels of exposure. Information useful in radon control strategies is also provided by the basic science undertaken in this program.

  3. Korean American mother and daughter communication on women's health topics.

    PubMed

    Park, Wansoo; Grindel, Cecelia Gatson

    2007-01-01

    The purpose of this study was to explore communication patterns about health behaviors and lifestyles between Korean mothers and daughters living in the United States. Demographic and general health information was also collected. Semi-structured interviews were conducted with nine Korean mother and daughter dyads. Korean mothers talked with their daughters about healthy diets and exercise but relied on daughters' schools to provide much of their daughters'health education information related to growth and developmental changes and women's health issues such as screening and HIV prevention practice. Intervention models to enhance mother/daughter health communication and to improve mothers' self care need to be investigated.

  4. Sexual Risk among African American Girls: Psychopathology and Mother-Daughter Relationships

    ERIC Educational Resources Information Center

    Donenberg, Geri R.; Emerson, Erin; Mackesy-Amiti, Mary Ellen

    2011-01-01

    Objective: To examine the associations among mental health problems, maternal monitoring and permissiveness, mother-daughter communication and attachment, and sexual behaviors among African American girls receiving outpatient psychiatric care. Youths with mental health problems report higher rates of HIV-risk behavior than do their peers, and…

  5. Melancholic Mothering: Mothers, Daughters and Family Violence

    ERIC Educational Resources Information Center

    Kenway, Jane; Fahey, Johannah

    2008-01-01

    Through selected theories of melancholia, this paper seeks to shed some fresh interpretive light on the reproduction and disruption of gender, violence and family turmoil across generations of mothers and daughters. The originality of the paper lies in its exploratory deployment of theories of melancholia to consider issues of women, violence and…

  6. Humanistic Treatment of Father-Daughter Incest.

    ERIC Educational Resources Information Center

    Giarretto, Henry

    1978-01-01

    Following a case study of father-daughter incest, the author comments on the prevalence of incest and describes Santa Clara County's Child Sexual Abuse Treatment Program (CSATP). The founding of CSATP, its treatment model for incestuous families, and its preliminary results are covered. (SJL)

  7. Sons, Daughters, and Intergenerational Social Support.

    ERIC Educational Resources Information Center

    Spitze, Glenna; Logan, John

    1990-01-01

    Examined effects of the number and gender composition of children on the receipt of social support by older persons. Effects varied with type of support: having daughters was most salient for telephone contact, while frequency of visiting was affected by both gender and number of children. (Author/TE)

  8. Zoonotic Anatrichosomiasis in a Mother and Daughter

    PubMed Central

    Hellstein, John W.; Lanzel, Emily A.

    2014-01-01

    Zoonotic anatrichosomiasis in a mother and daughter is reported. Both presented with a 10-week history of multiple painful oral ulcers. Biopsy specimens revealed the presence of small, coiled trichuroid nematodes with distinctive morphological features, including stichocytes and paired bacillary bands. This represents an unusual infection by a zoonotic Anatrichosoma species. PMID:24899034

  9. Conflict sources and responses in mother-daughter relationships: perspectives of adult daughters of aging immigrant women.

    PubMed

    Usita, Paul M; Du Bois, Barbara C

    2005-01-01

    Mother-daughter conflict sources and responses among immigrant families are not well understood. In the research reported here, in-depth interview data about conflict were collected from 11 adult daughters of Japanese immigrant mothers. Conflict sources were mothers' unsolicited advice, daughters and mothers not living up to expectations of the other, and daughters' independence of mothers. Responses to conflict included voicing concerns, displaying loyalty, and utilizing the assistance of family. Comparisons between immigrant and nonimmigrant mother-daughter dyads' conflict experiences are discussed, and suggestions for future research on mother-daughter conflict within the immigrant context are provided. PMID:15914425

  10. 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

  11. Anti-radon coating for mitigating indoor radon concentration

    NASA Astrophysics Data System (ADS)

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

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

  12. Radon and radon progeny in the Carlsbad Caverns

    SciTech Connect

    Cheng, Y.S.; Chen, T.R.; Wasiolek, P.T; Van Engen, A.

    1997-01-01

    Measurements were made in July 1994 to determine air exchange rate, aerosol characteristics, radon concentrations, and radon progeny activity size distributions in the Carlsbad Caverns. The measured radon concentrations were stable at a level of 1821{+-}55 Bq m{sup -3}(mean {+-}SD). Using a SF{sub 6} trace gas method, it was determined that stagnant air in the Caverns was exchanged once every 18 days. The stagnant air was a key factor in maintaining stable environmental conditions and radon concentration. The low air exchange and few aerosol sources inside the Caverns also contributed to the low aerosol concentrations of between 200 and 400 cm{sup -3} - orders of magnitude lower than mining, indoor, and outdoor environments. The alpha spectrum showed radon progeny but no thoron progeny. The activity size distribution of radon progeny showed typical bimodal distributions with higher unattached fractions than other natural environments. The high unattached fraction was attributed to the extremely low aerosol concentration. Considering the seasonal variation in radon concentration, the estimated cumulative exposure of 1.65 working level months (WLMs) for a worker spending 2000 h in the Carlsbad Caverns with the observed radon concentration seems high, but it is still below the recommended occupational exposure limit for underground uranium miners. 43 refs., 11 figs., 2 tabs.

  13. 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.

  14. Analysis of volatile-phase transport in soils using natural radon gas as a tracer

    SciTech Connect

    Chen, C.; Thomas, D.M.

    1994-01-01

    We have conducted a field study of soil gas transport processes using radon gas as a naturally occurring tracer. The experiment monitored soil gas radon activity, soil moisture, and soil temperature at depth; barometric pressure, rainfall, and wind speed were monitored at the soil surface. Linear and multiple regression analysis under natural environmental conditions are influenced by soil moisture content, barometric pressure variations, soil temperature, and soil structure. The effect of wind speed on subsurface radon activities under our field conditions has not been observed. 25 refs., 12 figs., 1 tab.

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

    SciTech Connect

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

    2014-11-11

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

  16. The application of moment analysis to the dynamic adsorption of radon by activated carbon

    NASA Astrophysics Data System (ADS)

    Gaul, Wayne C.

    The adsorption of radon by activated carbon has received a great deal of attention within the academic press because of the importance of determining the radon concentration in the living environment. The deposition of energy from 222Rn decay and the daughter products of 222Rn is considered significant probable cause agent for lung cancer in the general population. Therefore, study of the adsorption by activated carbon has focused on the ability to determine radon concentrations under static conditions. The adsorption of radon under dynamic conditions, from moving air, has not been studied adequately to determine the underlying properties associated with this phenomenon. No method of determining the properties associated with dynamic has been developed. This research has provided a method to accurately determine the attributes that control radon adsorption from moving air at two different temperatures. The characteristics of several common activated carbons were determined and correlated to current theories. Changes in carrier gas velocity were shown to affect the mass transfer characteristics which are represented by the van Deemter equation used in gas chromatography. The methodology can be used to determine specific parameters of gas adsorption from the experimental data and include; (1) the coefficient for axial dispersion (2) the tortuosity factor, and (3) the intraparticle diffusion coefficient. These parameters affect changes in the number of theoretical plates and the height equivalent of a theoretical plate which are related to interparticle and intraparticle diffusion along with resistance to mass transfer.

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

    SciTech Connect

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

    2012-12-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

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

  19. [Radiation exposure and risk of radon in the room air of Swiss houses].

    PubMed

    Burkart, W

    1986-01-01

    The radioactive noble gas radon, a member of the natural decay chains of uranium and thorium, enters the indoor environment in regionally highly diverging amounts. Subsoil of dwellings, building materials and drinking water are the main sources. In Switzerland and in many other countries, exposure of the lung tissue to the short lived radon decay products is the most important component of the radiation dose of the general public. Annual doses in areas with crystalline rock of high uranium content may reach the limits set up for occupational exposure. However, a clear link between cumulative exposure to radon daughters and elevation of the lung cancer incidence exists only for underground miners. The majority of human epidemiological studies point to a linear dose effect relationship. The indoor radon levels are determined by geology, building materials and techniques, climate and behaviour of the occupants. Experiences from Scandinavia and the Northern parts of America clearly indicate the possibility of cost-efficient remedial measures to reduce indoor radon levels.

  20. Ventilation, air confinement and high radon level in an underground gallery studied from profiles measurements.

    NASA Astrophysics Data System (ADS)

    Richon, P.; Perrier, F.; Sabroux, J.-C.; Pili, E.; Ferry, C.; Dezayes, C.; Voisin, V.

    2003-04-01

    An horizontal closed-end tunnel, 128 m long and 2 m in diameter, located within the eastern margin of the Belledonne crystalline basement, French Alps, near the west shore of the Roselend artificial lake, 600 m NE of the dam, has been instrumented since 1995 for radon emanation and deformation measurements. Radon bursts are repeatedly associated with transient deformation events induced by variations in lake levels (Trique et al., 1999). This high radon anomalies (up to 30,000 Bq.m-3) in the air of the tunnel result from its particular geometry, its excellent confinement, the water and radium-226 contents of rocks, and the crossing of several faults. We calculated the equilibrium factor F, directly proportional to air ventilation, from the ratios of radon-222 gas activity measured with an AlphaGUARDTM, and the Potential Alpha Energy Concentration (PAEC, in μJ.m-3) of its short-lived daughters measured with a TracerlabTM, simultaneously in five locations along the tunnel. The calculated equilibrium factors of 0.60 to 0.78 show that confinement is very good all along the tunnel. Fast Fourier Transform of the radon-222 signals measured during six months simultaneously with six BarasolTM distributed along the tunnel shows also the poor ventilation and the weak influence of atmospheric pressure and air temperature.

  1. 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...

  2. 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...

  3. Behavior of the 222Rn daughters on copper surfaces during cleaning

    SciTech Connect

    Wojcik, Marcin; Zuzel, Grzegorz

    2007-03-28

    Removal of the long-living 222Rn daughters (210Pb, 210Bi and 210Po) from the copper surface has been investigated. Different methods, like chemical etching and electropolishing, were applied to discs exposed earlier to a strong radon source. A long exposure assured effective accumulation of the 222Rn progenies on the copper surface. Cleaning efficiency for 210Pb was tested using a HPGe spectrometer, for 210Bi a beta spectrometer and for 210Po an alpha spectrometer were used. According to the conducted measurements electropolishing removes very effectively all the isotopes, while etching works only for lead and bismuth, for polonium the cleaning effect is practically negligible. Most probable 210Po is re-deposited on the treated surface.

  4. Removal of the long-lived 222Rn daughters from copper and stainless steel surfaces

    NASA Astrophysics Data System (ADS)

    Zuzel, G.; Wójcik, M.

    2012-06-01

    Removal of the long-lived 222Rn daughters from copper and stainless steel surfaces was investigated. Etching and electropolishing were applied to discs exposed earlier to a strong radon source for 210Pb, 210Bi and 210Po deposition. Cleaning efficiency for 210Pb was tested with a n-type high purity germanium spectrometer, for 210Bi a beta spectrometer and for 210Po an alpha spectrometer was used. According to the performed measurements electropolishing removes very effectively all the isotopes from copper and stainless steel. Copper etching reduces efficiently lead and bismuth however for polonium the effect is negligible because of its fast re-deposition. For stainless steel, etching is much more effective compared to copper and it also works for 210Po.

  5. Paternal smoking habits affect the reproductive life span of daughters.

    PubMed

    Fukuda, Misao; Fukuda, Kiyomi; Shimizu, Takashi; Nobunaga, Miho; Andersen, Elisabeth Wreford; Byskov, Anne Grete; Andersen, Claus Yding

    2011-06-30

    The present study assessed whether the smoking habits of fathers around the time of conception affected the period in which daughters experienced menstrual cycles (i.e., the reproductive life span). The study revealed that the smoking habits of the farther shortened the daughters' reproductive life span compared with daughters whose fathers did not smoke.

  6. Application of an equilibrium-based model for diffusion barrier charcoal canisters in a small volume non-steady state radon chamber.

    PubMed

    Lehnert, A L; Thompson, K H; Kearfott, K J

    2011-02-01

    Radon in indoor air is often measured using activated charcoal in canisters. These are generally calibrated using large, humidity- and temperature-controlled radon chambers capable of maintaining a constant radon concentration over several days. Reliable and reproducible chambers are expensive and may be difficult to create and maintain. This study characterizes a small radon chamber in which Rn gas is allowed to build up over a period of several days for use in charcoal canister calibration and educational demonstrations, as well as various radon experiments using charcoal canisters. Predictive models have been developed that accurately describe radon gas kinetics in the charcoal canisters. Three models are available for kinetics in the small chamber with and without radon-adsorbing charcoal canisters. Presented here are both theoretical and semi-empirical applications of this equilibrium-based model of radon adsorption as applied to canisters in the small chamber. Several charcoal canister experiments in the small chamber with an equilibrium-based model of radon adsorption applied are reported. Results show that it is necessary to include a continuous radon monitor in the chamber during canister exposures, as the radon removal rate is highly variable. Furthermore, the presence of the canisters significantly decreases the amount of radon in the small chamber, especially when several canisters are present. It was found that canister response in the small chamber is largely consistent with the equilibrium-based model for both applications, with average errors of 1% for the theoretical application and -4% for the semi-empirical approach.

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

    PubMed

    Műllerová, Monika; Holý, Karol; Bulko, Martin

    2014-07-01

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

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

    SciTech Connect

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

    1990-01-01

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

  9. Comparative dosimetry for radon and thoron in high background radiation areas in China.

    PubMed

    Kudo, H; Tokonami, S; Omori, Y; Ishikawa, T; Iwaoka, K; Sahoo, S K; Akata, N; Hosoda, M; Wanabongse, P; Pornnumpa, C; Sun, Q; Li, X; Akiba, S

    2015-11-01

    The present study focuses on internal exposure caused by the inhalation of radon and thoron progenies because the internal exposures have not yet been clarified. For their dose assessment, radon, thoron and thoron progeny concentrations were measured by passive monitors over a long period (for 6 months). Consequently, radon, thoron and equilibrium equivalent thoron concentrations were given as 124 ± 78, 1247 ± 1189 and 7.8 ± 9.1 Bq m(-3), respectively. Annual effective doses are estimated to be 3.1 ± 2.0 mSv for radon and 2.2 ± 2.5 mSv for thoron. Total dose are estimated to be 5.3 ± 3.5 mSv a(-1). The present study has revealed that the radon dose was comparable with the thoron dose, and the total dose was ∼2 times higher than the worldwide average.

  10. Determination of the minimum measurement time for estimating long-term mean radon concentration.

    PubMed

    Janik, M; Łoskiewicz, J; Tokonami, S; Kozak, K; Mazur, J; Ishikawa, T

    2012-11-01

    Radon measurements, as do any measurements, include errors in their readings. The relative values of such errors depend principally on the measurement methods used, the radon concentration to be measured and the duration of the measurements. Typical exposure times for radon surveys using passive detectors [nuclear track detectors, activated charcoal, electrostatic (E-perm), etc.)] may extend from a few days to months, whereas, in the case of screening methods utilising active radon monitors (AlphaGUARD, RAD7, EQF, etc.), the measurements may be completed quickly within a few hours to a few days. Thus, the latter may have relatively large error values, which affect the measurement accuracy significantly compared with the former measurements made over long time periods. The method presented in this paper examines the uncertainty of a short-term radon measurement as an estimate of the long-term mean and suggests a minimum measurement time to achieve a given margin of uncertainty of that estimate. PMID:22923240

  11. Daily and seasonal variations of radon activity measured in Mystery Cave

    SciTech Connect

    Lively, R.S. ); Krafthefer, B. ); Netherton, W. )

    1993-03-01

    Mystery Cave, southeastern Minnesota, is the site of an ongoing study of how radon and radon progeny are affected by meteorological changes in and about the dave. Data on radon, radon progeny, temperature, relative humidity, barometric pressure, wind speed and direction, and rainfall are collected at 4-hour intervals at different locations within and just outside the cave. During winter months, average ambient radon levels ranged from 5 to 200 pCi/L. Transient levels above 500 pCi/L tended to correlate with failing barometric pressure, but not with the magnitude of [Delta]P. In summer, average ambient radon increased to around 300 pCi/L with short-term levels exceeding 500 pCi/L. Fluctuations related to temperature were also noted. Radon progeny generally correlate with radon and both showed rates of change faster than ingrowth or decay. In addition to the time variations in the radon activity levels, pulses were observed between monitoring locations. The probable correlation of radon-activity transport with aboveground meteorological changes and preliminary data on cave airflow is being studied. Previous grab sampling with Lucas cells and integrating alpha-track devices did not show either the 10- to 100-fold daily fluctuations or the pulses. As more continuous data become available, it is increasingly evident that radon fluctuates on time scales that range from hours to years, in response to conditions both inside and outside the cave system. Funding for this project was approved by the Minnesota legislature ML 1991, Chapter 264, Art. 1, Sec. 14, subd. 3 (I) as recommended by the Legislative Commission on Minnesota Resources from the Minnesota Future Resources Fund.

  12. Effect of radon transport in groundwater upon gamma-ray borehole logs

    SciTech Connect

    Nelson, P.H.; Rachiele, R.; Smith, A.

    1980-09-01

    Granitic rock at an experimental waste storage site at Stripa, Sweden, is unusually high in natural radioelements (40 ppM uranium) with higher concentrations occurring locally in thin chloritic zones and fractures. Groundwater seeping through fractures into open boreholes is consequently highly anomalous in its radon content, with activity as high as one microcurie per liter. When total count gamma-ray logs are run in boreholes where groundwater inflow is appreciable, the result is quite unusual: the radon daughter activity in the water adds considerably to the contribution from the rock, and in fact often dominates the log response. The total gamma activity increases where radon-charged groundwater enters a borehole, and remains at a high level as the water flows along the hole in response to the hydraulic gradient. As a consequence, the gamma log serves as a flow profile, locating zones of water entry (or loss) by an increase (or decrease) in the total gamma activity. A simple model has been developed for flow through a thin crack emanating radon at a rate E showing that the radon concentration of water entering a hole is E/..lambda..h, where ..lambda.. is the radon decay rate and h the crack aperture, assuming that the flow rate and crack source area are such that an element of water resides within the source area for several radon half-lives or more. Concentration measurements can provide a measurement of the inflow rate. Data from the 127-mm holes in the time-scale drift behave in this fashion.

  13. Radon entry into basements: Approach, experimental structures, and instrumentation of the small structures research project

    SciTech Connect

    Fisk, W.J.; Modera, M.P.; Sextro, R.G.; Garbesi, K.; Wollenberg, H.A.; Narasimhan, T.N.; Nuzum, T.; Tsang, Y.W.

    1992-02-01

    We describe the experimental approach, structures, and instrumentation of a research project on radon generation and transport in soil and entry into basements. The overall approach is to construct small precisely-fabricated basements in areas of different geology and climate, to control the pressures and ventilation rates in the structures, and to monitor radon concentrations and other relevant parameters over a period of one year or more. Two nearly air-tight structures have been constructed at the first site. The floor of each structure contains adjustable-width slots that serve as the only significant pathway for advective entry of radon. A layer of gravel underlays the floor of one structure; otherwise they are identical. The structures are instrumented for continuous or periodic monitoring of soil, structural, and meteorological parameters that affect radon entry. The pressure difference that drives advective radon entry can be maintained constant or varied over time. Soil gas and radon entry rates and associated parameters, such as soil gas pressures and radon concentrations, have been monitored for a range of steady-state and time-varying pressure differences between the interior of the structure and the soil. Examples of the experimentally-measured pressure and permeability fields in the soil around a structure are presented and discussed.

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

    NASA Astrophysics Data System (ADS)

    Chauhan, R. P.; Kumar, Amit

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

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

    SciTech Connect

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

    2003-05-12

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

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

    PubMed Central

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

    2013-01-01

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

  17. Correlating precursory declines in groundwater radon with earthquake magnitude.

    PubMed

    Kuo, T

    2014-01-01

    Both studies at the Antung hot spring in eastern Taiwan and at the Paihe spring in southern Taiwan confirm that groundwater radon can be a consistent tracer for strain changes in the crust preceding an earthquake when observed in a low-porosity fractured aquifer surrounded by a ductile formation. Recurrent anomalous declines in groundwater radon were observed at the Antung D1 monitoring well in eastern Taiwan prior to the five earthquakes of magnitude (Mw ): 6.8, 6.1, 5.9, 5.4, and 5.0 that occurred on December 10, 2003; April 1, 2006; April 15, 2006; February 17, 2008; and July 12, 2011, respectively. For earthquakes occurring on the longitudinal valley fault in eastern Taiwan, the observed radon minima decrease as the earthquake magnitude increases. The above correlation has been proven to be useful for early warning local large earthquakes. In southern Taiwan, radon anomalous declines prior to the 2010 Mw 6.3 Jiasian, 2012 Mw 5.9 Wutai, and 2012 ML 5.4 Kaohsiung earthquakes were also recorded at the Paihe spring. For earthquakes occurring on different faults in southern Taiwan, the correlation between the observed radon minima and the earthquake magnitude is not yet possible.

  18. LaPO4 Nanoparticles Doped with Actinium-225 that Partially Sequester Daughter Radionuclides

    SciTech Connect

    Woodward, Jonathan; Kennel, Steve J; Stucnkey, Alan; Osborne, Dustin; Wall, Jonathan; Rondinone, Adam Justin; Standaert, Robert F; Mirzadeh, Saed

    2011-01-01

    vitro analyses, conducted over a one month interval demonstrated that ~50% of the daughter was retained within the La(225Ac)PO4 NPs at any time over that time frame. Although most of the -rays from radionuclides in the 225Ac decay chain are too energetic to be captured efficiently by SPECT detectors, appropriate energy windows were found that provided dramatic microSPECT images of the NP distribution in vivo. We conclude that La(225Ac)PO4 mAb conjugates can be targeted efficiently to mouse lung while partially retaining daughter products and that targeting can be monitored by biodistribution techniques and microSPECT imaging.

  19. LaPO4 nanoparticles doped with actinium-225 that partially sequester daughter radionuclides.

    PubMed

    Woodward, Jonathan; Kennel, Stephen J; Stuckey, Alan; Osborne, Dustin; Wall, Jonathan; Rondinone, Adam J; Standaert, Robert F; Mirzadeh, Saed

    2011-04-20

    increased to ∼87% at 120 h. In vitro analyses, conducted over a 1 month interval, demonstrated that ∼50% of the daughters were retained within the La((225)Ac)PO(4) NPs at any point over that time frame. Although most of the γ-rays from radionuclides in the (225)Ac decay chain are too energetic to be captured efficiently by SPECT detectors, appropriate energy windows were found that provided dramatic microSPECT images of the NP distribution in vivo. We conclude that La((225)Ac)PO(4)-mAb 201B conjugates can be targeted efficiently to mouse lung while partially retaining daughter products and that targeting can be monitored by biodistribution techniques and microSPECT imaging.

  20. LaPO4 nanoparticles doped with actinium-225 that partially sequester daughter radionuclides.

    PubMed

    Woodward, Jonathan; Kennel, Stephen J; Stuckey, Alan; Osborne, Dustin; Wall, Jonathan; Rondinone, Adam J; Standaert, Robert F; Mirzadeh, Saed

    2011-04-20

    increased to ∼87% at 120 h. In vitro analyses, conducted over a 1 month interval, demonstrated that ∼50% of the daughters were retained within the La((225)Ac)PO(4) NPs at any point over that time frame. Although most of the γ-rays from radionuclides in the (225)Ac decay chain are too energetic to be captured efficiently by SPECT detectors, appropriate energy windows were found that provided dramatic microSPECT images of the NP distribution in vivo. We conclude that La((225)Ac)PO(4)-mAb 201B conjugates can be targeted efficiently to mouse lung while partially retaining daughter products and that targeting can be monitored by biodistribution techniques and microSPECT imaging. PMID:21434681

  1. Kinetics of the water/air phase transition of radon and its implication on detection of radon-in-water concentrations: practical assessment of different on-site radon extraction methods.

    PubMed

    Schubert, Michael; Paschke, Albrecht; Bednorz, Denise; Bürkin, Walter; Stieglitz, Thomas

    2012-08-21

    The on-site measurement of radon-in-water concentrations relies on extraction of radon from the water followed by its detection by means of a mobile radon-in-air monitor. Many applications of radon as a naturally occurring aquatic tracer require the collection of continuous radon concentration time series, thus necessitating the continuous extraction of radon either from a permanent water stream supplied by a water pump or directly from a water body or a groundwater monitoring well. Essentially, three different types of extraction units are available for this purpose: (i) a flow-through spray chamber, (ii) a flow-through membrane extraction module, and (iii) a submersible (usually coiled) membrane tube. In this paper we discuss the advantages and disadvantages of these three methodical approaches with particular focus on their individual response to instantaneously changing radon-in-water concentrations. After a concise introduction into theoretical aspects of water/air phase transition kinetics of radon, experimental results for the three types of extraction units are presented. Quantitative suggestions for optimizing the detection setup by increasing the water/air interface and by reducing the air volume circulating through the degassing unit and radon detector are made. It was shown that the flow-through spray chamber and flow-through membrane perform nearly similarly, whereas the submersible membrane tubing has a significantly larger delay in response to concentration changes. The flow-through spray chamber is most suitable in turbid waters and to applications where high flow rates of the water pump stream can be achieved (e.g., where the power supply is not constrained by field conditions). The flow-through membrane is most suited to radon extraction from clear water and in field conditions where the power supply to a water pump is limited, e.g., from batteries. Finally, the submersible membrane tube is most suitable if radon is to be extracted in situ without

  2. Kinetics of the water/air phase transition of radon and its implication on detection of radon-in-water concentrations: practical assessment of different on-site radon extraction methods.

    PubMed

    Schubert, Michael; Paschke, Albrecht; Bednorz, Denise; Bürkin, Walter; Stieglitz, Thomas

    2012-08-21

    The on-site measurement of radon-in-water concentrations relies on extraction of radon from the water followed by its detection by means of a mobile radon-in-air monitor. Many applications of radon as a naturally occurring aquatic tracer require the collection of continuous radon concentration time series, thus necessitating the continuous extraction of radon either from a permanent water stream supplied by a water pump or directly from a water body or a groundwater monitoring well. Essentially, three different types of extraction units are available for this purpose: (i) a flow-through spray chamber, (ii) a flow-through membrane extraction module, and (iii) a submersible (usually coiled) membrane tube. In this paper we discuss the advantages and disadvantages of these three methodical approaches with particular focus on their individual response to instantaneously changing radon-in-water concentrations. After a concise introduction into theoretical aspects of water/air phase transition kinetics of radon, experimental results for the three types of extraction units are presented. Quantitative suggestions for optimizing the detection setup by increasing the water/air interface and by reducing the air volume circulating through the degassing unit and radon detector are made. It was shown that the flow-through spray chamber and flow-through membrane perform nearly similarly, whereas the submersible membrane tubing has a significantly larger delay in response to concentration changes. The flow-through spray chamber is most suitable in turbid waters and to applications where high flow rates of the water pump stream can be achieved (e.g., where the power supply is not constrained by field conditions). The flow-through membrane is most suited to radon extraction from clear water and in field conditions where the power supply to a water pump is limited, e.g., from batteries. Finally, the submersible membrane tube is most suitable if radon is to be extracted in situ without

  3. Daughters mimic sterile neutrinos (almost!) perfectly

    SciTech Connect

    Hasenkamp, Jasper

    2014-09-01

    Since only recently, cosmological observations are sensitive to hot dark matter (HDM) admixtures with sub-eV mass, m{sub hdm}{sup eff} < eV, that are not fully-thermalised, Δ N{sub eff} < 1. We argue that their almost automatic interpretation as a sterile neutrino species is neither from theoretical nor practical parsimony principles preferred over HDM formed by decay products (daughters) of an out-of-equilibrium particle decay. While daughters mimic sterile neutrinos in N{sub eff} and m{sub hdm}{sup eff}, there are opportunities to assess this possibility in likelihood analyses. Connecting cosmological parameters and moments of momentum distribution functions, we show that—also in the case of mass-degenerate daughters with indistinguishable main physical effects—the mimicry breaks down when the next moment, the skewness, is considered. Predicted differences of order one in the root-mean-squares of absolute momenta are too small for current sensitivities.

  4. Trkalian fields and Radon transformation

    NASA Astrophysics Data System (ADS)

    Saygili, K.

    2010-03-01

    We write the spherical curl transformation for Trkalian fields using differential forms. Then we consider Radon transform of these fields. The Radon transform of a Trkalian field satisfies a corresponding eigenvalue equation on a sphere in transform space. The field can be reconstructed using knowledge of the Radon transform on a canonical hemisphere. We consider relation of the Radon transformation with Biot-Savart integral operator and discuss its transform introducing Radon-Biot-Savart operator. The Radon transform of a Trkalian field is an eigenvector of this operator. We also present an Ampere-law type relation for these fields. We apply these to Lundquist solution. We present a Chandrasekhar-Kendall-type solution of the corresponding equation in the transform space. Lastly, we focus on the Euclidean topologically massive Abelian gauge theory. The Radon transform of an anti-self-dual field is related by antipodal map on this sphere to the transform of the self-dual field obtained by inverting space coordinates. The Lundquist solution provides an example of quantization of topological mass in this context.

  5. Radon daughter disequilibria and lead systematics in the western North Atlantic

    NASA Astrophysics Data System (ADS)

    Hussain, N.; Church, T. M.; VéRon, Alain J.; Larson, R. E.

    1998-01-01

    Concentrations of 222Rn and 210Pb were measured in the North Atlantic troposphere in 1989 between April 12 and 28, during the Sulfide Experiment (SEX) Cruise I, and those of 222Rn, 210Pb and 210Po, between October 24 and November 9, during the SEX Cruise II. Concentrations of 210Pb and 210Po were also measured in the rain water, surface seawater, and marine microlayer collected during the SEX Cruise II Other data used and published previously include stable lead and its isotopes [Vèron et al., 1992, 1993] on parallel samples. Low 222Rn contents, of the order of 0.1 and 0.3 Bq m-3, were found in the marine air, while continental air showed nearly 10 times higher concentrations of 222Rn. These results corroborate with the air mass trajectory analyses and continental signatures of stable lead isotopes. Significant correlation is found between 222Rn and 210Pb on the aerosol, indicative of excess continental 222Rn supporting the ingrowth of 210Pb from the atmosphere, in spite of its first-order removal by precipitation. Correlation between 210Pb and stable Pb on the aerosol and in the precipitation document the source of pollutant lead from the continental surface. Mean residence times of marine aerosol based on 210Pb is estimated to be 5.4±1.8 days during the April cruise and 19.7±1.9 days during the October cause. Corresponding deposition velocity for 210Pb is estimated to be 1.9±1.9 cm s-1, a value that suggests the dominant role of precipitation scavenging, or aerosol scavenging by larger host phases such as dust or sea salt. Excess 210Po activities are found on the aerosol relative to what would be expected based on 210Pb and the aerosol residence times. In surface seawaters, deficiencies of 210Po are observed. Mechanisms of 210Po enrichment in atmospheric aerosol may include enrichments from the organic components of marine microlayer, sea-salt aerosol, dust, or air-sea exchange of volatile organo-polonium species.

  6. Temporal distributions of radiostrontium isotopes and radon daughters in rain water during a thunderstorm

    SciTech Connect

    Burchfield, L.A.; Akridge, J.D.; Kuroda, P.K.

    1983-10-20

    The concentrations of /sup 89/Sr, /sup 90/Sr, /sup 137/Cs, /sup 210/Pb, /sup 212/Po were measured in sequentially sampled rain water during a thunderstorm occurring at Fayetteville, Arkansas, on January 29, 1981. Approximately concordant mean residence times ranging from 43 to 136 days were obtained from the observed ratios of /sup 89/Sr//sup 90/Sr and /sup 210/Pb//sup 210/Po ratio was found to correlate negatively with the /sup 210/Po//sup 210/Pb ratio. The variation of the /sup 212/Pb//sup 210/Pb ratio appeared to have resulted from turbulent mixing of the air masses, and it increased sharply after the rainfall reached a peak value.

  7. Intercomparison of Retrospective Radon Detectors

    SciTech Connect

    Field, R W.; Steck, D J.; Parkhurst, Maryann ); Mahaffey, Judith A. ); Alavanja, M C.

    1998-11-01

    We performed both a laboratory and 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, Pb-210, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha emission of a Pb-210 decay product, Po-210. The detector's track density generation rate (tracks cm{sup -2} hr{sup -1}) 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 Po-210 and hence, the cumulative radon gas exposure. The goals of the intercomparison were to: (1) 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, (2) 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 (3) 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 Po-210 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.

  8. Measurements of radon flux and soil-gas radon concentration along the Main Central Thrust, Garhwal Himalaya, using SRM and RAD7 detectors

    NASA Astrophysics Data System (ADS)

    Bourai, Abhay; Aswal, Sunita; Dangwal, Anoop; Rawat, Mukesh; Prasad, Mukesh; Naithani, Nagendra; Joshi, Veena; Ramola, Rakesh

    2013-08-01

    Radon in the Earth's crust or soil matrix is free to move only if its atoms find their way into pores or capillaries of the matrix. 222Rn atoms from solid mineral grains get into air, filling pores through emanation process. Then 222Rn enters into the atmosphere from air-filled pores by exhalation process. The estimation of radon flux from soil surface is an important parameter for determining the source term for radon concentration modeling. In the present investigation, radon fluxes and soil-gas radon concentration have been measured along and around the Main Central Thrust (MCT) in Uttarkashi district of Garhwal Himalaya, India, by using Scintillation Radon Monitor (SRM) and RAD7 devices, respectively. The soil radon gas concentration measured by RAD7 with soil probe at the constant depth was found to vary from 12 ± 3 to 2330 ± 48 Bq·m-3 with geometrical mean value of 302 ± 84 Bq·m-3. Th significance of this work is its usefulness from radiation protection point of view.

  9. 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

  10. Shared vision between fathers and daughters in family businesses: the determining factor that transforms daughters into successors.

    PubMed

    Overbeke, Kathy K; Bilimoria, Diana; Somers, Toni

    2015-01-01

    Family businesses are critical to the United States economy, employing 63% of the workforce and generating 57% of GDP (University of Vermont, 2014). Family business continuity, however, remains elusive as approximately 70% of family businesses do not survive the second generation (Poza, 2013). In order to augment our understanding of how next generation leaders are chosen in family businesses, we examine daughter succession. Using a sample of pairs of family business fathers and daughters and drawing on an earlier study of the dearth of successor daughters in family businesses (Overbeke et al., 2013), we reveal that shared vision between fathers and daughters is central to daughter succession. Self-efficacy and gender norms influence shared vision and when fathers and daughters share a vision for the future of the company, daughters are likely to be transformed into successors.

  11. Shared vision between fathers and daughters in family businesses: the determining factor that transforms daughters into successors

    PubMed Central

    Overbeke, Kathy K.; Bilimoria, Diana; Somers, Toni

    2015-01-01

    Family businesses are critical to the United States economy, employing 63% of the workforce and generating 57% of GDP (University of Vermont, 2014). Family business continuity, however, remains elusive as approximately 70% of family businesses do not survive the second generation (Poza, 2013). In order to augment our understanding of how next generation leaders are chosen in family businesses, we examine daughter succession. Using a sample of pairs of family business fathers and daughters and drawing on an earlier study of the dearth of successor daughters in family businesses (Overbeke et al., 2013), we reveal that shared vision between fathers and daughters is central to daughter succession. Self-efficacy and gender norms influence shared vision and when fathers and daughters share a vision for the future of the company, daughters are likely to be transformed into successors. PMID:26074830

  12. Radon-related backgrounds in the LUX dark matter search

    DOE PAGESBeta

    Bradley, A.; Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bernard, E.; Bernstein, A.; Byram, D.; Cahn, S. B.; et al

    2015-01-01

    The LUX detector is currently in operation at the Davis Campus at the 4850’ level of the Sanford Underground Research Facility (SURF) in Lead, SD to directly search for WIMP dark matter. Knowing the type and rate of backgrounds is critical in a rare, low energy event search, and LUX was designed, constructed, and deployed to mitigate backgrounds, both internal and external. An important internal background are decays of radon and its daughters. These consist of alpha decays, which are easily tagged and are a tracer of certain backgrounds, and beta decays, some of which are not as readily taggedmore » and present a background for the WIMP search. We report on studies of alpha decay and discuss implications for the WIMP search.« less

  13. Radon-related backgrounds in the LUX dark matter search

    SciTech Connect

    Bradley, A.; Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Bernard, E.; Bernstein, A.; Byram, D.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chapman, J. J.; Chiller, A. A.; Chiller, C.; Coffey, T.; Currie, A.; de Viveiros, L.; Dobi, A.; Dobson, J.; Druszkiewicz, E.; Edwards, B.; Faham, C. H.; Fiorucci, S.; Flores, C.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G.D.; Hall, C.; Hertel, S. A.; Horn, M.; Huang, D. Q.; Ihm, M.; Jacobsen, R. G.; Kazkaz, K.; Knoche, R.; Larsen, N. A.; Lee, C.; Lindote, A.; Lopes, M. I.; Malling, D. C.; Mannino, R.; McKinsey, D. N.; Mei, D. -M.; Mock, J.; Moongweluwan, M.; Morad, J.; Murphy, A. St.J.; Nehrkorn, C.; Nelson, H.; Neves, F.; Ott, R. A.; Pangilinan, M.; Parker, P. D.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Shutt, T.; Silva, C.; Solovov, V. N.; Sorensen, P.; O'Sullivan, K.; Sumner, T. J.; Szydagis, M.; Taylor, D.; Tennyson, B.; Tiedt, D. R.; Tripathi, M.; Uvarov, S.; Verbus, J. R.; Walsh, N.; Webb, R.; White, J. T.; Witherell, M. S.; Wolfs, F. L.H.; Woods, M.; Zhang, C.

    2015-01-01

    The LUX detector is currently in operation at the Davis Campus at the 4850’ level of the Sanford Underground Research Facility (SURF) in Lead, SD to directly search for WIMP dark matter. Knowing the type and rate of backgrounds is critical in a rare, low energy event search, and LUX was designed, constructed, and deployed to mitigate backgrounds, both internal and external. An important internal background are decays of radon and its daughters. These consist of alpha decays, which are easily tagged and are a tracer of certain backgrounds, and beta decays, some of which are not as readily tagged and present a background for the WIMP search. We report on studies of alpha decay and discuss implications for the WIMP search.

  14. Impulsive radon emanation on a creeping segment of the San Andreas fault, California

    USGS Publications Warehouse

    King, C.-Y.

    1985-01-01

    Radon emanation was continuously monitored for several months at two locations along a creeping segment of the San Andreas fault in central California. The recorded emanations showed several impulsive increases that lasted as much as five hours with amplitudes considerably larger than meteorologically induced diurnal variations. Some of the radon increases were accompanied or followed by earthquakes or fault-creep events. They were possibly the result of some sudden outbursts of relatively radon-rich ground gas, sometimes triggered by crustal deformation or vibration. ?? 1985 Birkha??user Verlag.

  15. Contribution of atmospherical radon to in-situ scintillation gamma spectrometry data.

    PubMed

    Klusoň, J; Thinová, L

    2011-08-01

    In-situ gamma spectrometry can be used for monitoring and determining natural and man-made radionuclide concentrations in the environment. The low detection limit of potential contaminants depends on the natural background variations, including variations in the atmospheric concentrations of radon and its decay products. The scintillation spectrometer response for atmospheric radon was simulated by the Monte Carlo method, and the results were compared with the experimental measurements over large water surfaces. The contributions of atmospheric radon to the natural background were assessed. PMID:21129988

  16. Surface radioactivity resulting from the deposition of /sup 222/Rn daughter products

    SciTech Connect

    Lively, R.S.; Ney, E.P.

    1987-04-01

    This paper describes the relationship between the /sup 222/Rn in air, and the level of surface radioactivity that results from the build-up and decay of the daughter isotope, /sup 210/Pb. Samples of /sup 222/Rn were collected from Mystery Cave, which is located in southeastern Minnesota and from the basement of a house in Minneapolis, MN. Lead-210 was measured on surfaces within the cave, on a rock removed from the cave, and on a basement window. Surface alpha activities were measured on the rock sample and on the window. Radon-222 concentrations in the cave air ranged from 3 to 13 kBq m-3. In the basement, /sup 222/Rn levels were between 0.2 and 0.4 kBq m-3. Virtually all the surface radioactivity resulted from the deposition and decay of airborne /sup 222/Rn daughter products and was not produced by the decay of U in the rock. Radon-222 concentrations in the cave air were almost 30 times higher than in the basement air; however, the surface /sup 210/Pb activity in the cave was 100 times higher than that in the basement. This suggests that in the cave air, /sup 222/Rn daughter products are more likely to reach the walls and decay to /sup 210/Pb. The measurements of surface alpha activity did not show a similar trend primarily because /sup 210/Pb had diffused further into the coating of dirt on the rock than into the glass of the window. The resulting surface activity of the rock was lower than expected based on the /sup 210/Pb concentration, because many of the alpha-emitting nuclei were at depths beyond the range of emitted alpha particles. On surfaces where the penetration range of alpha particles is greater than the diffusion depth of /sup 210/Pb atoms, either the /sup 210/Pb concentration or surface alpha-activity measurements should provide estimates of average long-term /sup 222/Rn concentrations.

  17. United role of radon decay products and nano-aerosols in radon dosimetry

    NASA Astrophysics Data System (ADS)

    Smerajec, M.; Vaupotič, J.

    2012-04-01

    The major part of human exposure to natural radiation originates from inhalation of radon (Rn) and radon short-lived decay products (RnDP: 218Po, 214Pb, 214Bi and 214Po). RnDP are formed as a result of α-transformation of radon. In the beginning they are positive ions which neutralize and form clusters with air molecules, and later partly attach to background aerosol particles in indoor air. Eventually, they appear as radioactive nano-aerosols with a bimodal size distribution in ranges of 1-10 nm (unattached RnDP) and of 200-800 nm (attached RnDP). When inhaled, they are deposited in the respiratory tract. Deposition is more efficient for smaller particles. Therefore, the fraction (fun) of the unattached RnDP, which appears to be influenced by the number concentration and size distribution of general (background) aerosols in the ambient air, has a crucial role in radon dosimetry. Radon, radon decay products and general aerosols have been monitored simultaneously in the kitchen of a typical rural house under real living conditions, also comprising four human activities generating particular matter: cooking and baking, as two typical activities in kitchen, and cigarette smoking and candle burning. In periods without any human activity, the total number concentration of general aerosol ranged from 1000 to 3000 cm-3,with the geometric mean of particle diameter in the range of 60-68 nm and with 0.1-1 % of particles smaller than 10 nm. Preparation of coffee changed the concentration to 193,000 cm-3, the geometric mean of diameter to 20 nm and fraction of particles smaller than 10 nm to 11 %. The respective changes were for baking cake: 503,000 cm-3, 17 nm and 19 %, for smoking:423,000 cm-3, 83 nm and 0.4 %, and forcandle burning: 945,000 cm-3, 8 nm and 85 %. While, as expected, a reduction of fun was observed during cooking, baking and smoking, when larger particles were emitted, fun did not increase during candle burning with mostly particles smaller than 10 nm

  18. Influence of urbanization on radon potential in Zhongshan City in the southern China

    NASA Astrophysics Data System (ADS)

    Wang, N.

    2015-12-01

    Radon and radon progeny are the most important contribution to dose from natural sources of radiation. Most studies have demonstrated an increased risk of lung cancer at high concentration of radon for the public. Radon potential map is an essential approach for radon risk assessment. The radon potential map is based on the measured data of soil gas radon concentration and soil air permeability, combined with GIS technology, in Zhongshan City in the Southern China. The preliminary radon survey in ZC was conducted using a portable semiconductor radon monitor RAD-7 and soil air permeability instrument Rad-jok, covering a total area of 1800 km2. The sampling depth for soil gas radon measurement in the field was at the depth of 80 cm below the ground. 222Rn activity concentrations varyed between 0.74 and 158 kBq/m3, and 220Rn between 0.02 and 235 kBq/m3 in soil gas. The average value of 222Rn and 220Rn was 67.6 and 74.8 kBq/m3, respectively. The results show that: (1) the characteristics and distributions of 222Rn/220Rn concentration from soil gas in ZC are obviously related with local lithology (the Middle and the Late Jurassic and the Cretaceous biotitic-granite) and geological formation. High 222Rn/220Rn concentrations were observed in soil gas in the outcrops of weathered granite or filled back granite sands. (2) The distribution model of 220Rn is as same as that of 222Rn. The Wuguishan Mountain areas and in the south-east areas of ZC, covering with granite rocks, are high radon risk districts; the central zones in ZC are low radon potential areas, and part of the northern districts are medium radon potential areas. (3) Urbanization has increased local radon risk in some districts in the west and the north of ZC, where now covering several meters depth weathered granite products, but deposited the Quaternary sediments near surface before. The research was supported by National Natural Science Foundation of China (No. 41474107, No.41274133 and 41074096).

  19. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

    Soil based building materials known to contain various amounts of natural radionuclide mainly 238U and 232Th series and 40K. 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 222Radon and its progenies which arise from the decay of 226Ra. 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-3, 192 Bq m-3, 176 Bq m-3 and 28 Bq m-3, respectively. The result indicates that the radon concentration in the studied building materials have more than 100 Bq m-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-1, 4.85 mSv y-1, 4.44 mSv y-1 and 0.72 mSv y-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-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.

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

    PubMed

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

    2014-10-01

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

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

    PubMed

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

    2014-10-01

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

  3. Relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province, China

    SciTech Connect

    Qiao, Y.L.; Taylor, P.R.; Yao, S.X.; Schatzkin, A.; Mao, B.L.; Lubin, J.; Rao, J.Y.; McAdams, M.; Xuan, X.Z.; Li, J.Y. )

    1989-01-01

    We studied the relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province in the People's Republic of China. Interviews were conducted in 1985 with 107 living tin miners with lung cancer and an equal number of age-matched controls from among tin miners without lung cancer to obtain information on lung cancer risk factors including a detailed history of employment and tobacco use. Occupational history was combined with extensive industrial hygiene data to estimate cumulative working level months (WLM) of radon daughter exposure. Similar data were also used to estimate arsenic exposure for control in the analysis. Results indicate an increased risk of lung cancer for water pipe smoking, a traditional form of tobacco use practiced in 91% of cases and 85% of controls. The use of water pipes was associated with a twofold elevation in risk when compared with tobacco abstainers, and a dose-response relation was observed with increasing categories of pipe-year (dose times duration) usage. Estimated WLM of radon exposure varied from 0 to 1,761 among subjects but averaged 515 in cases versus only 244 in controls. Analyses indicated that the persons in the highest quarter of the radon exposure distribution had an odds ratio (OR) = 9.5 (95% confidence interval = 2.7-33.1) compared to persons without radon exposure after controlling for arsenic exposure and other potential confounders. Examination of duration and rate of radon exposure indicated higher risk associated with long duration as opposed to high rate of exposure. Cross-categorizations of radon exposure and tobacco use suggest greater risk associated with radon exposure than tobacco in these workers.

  4. Parents' personality clusters and eating disordered daughters' personality and psychopathology.

    PubMed

    Amianto, Federico; Ercole, Roberta; Marzola, Enrica; Abbate Daga, Giovanni; Fassino, Secondo

    2015-11-30

    The present study explores how parents' personality clusters relate to their eating disordered daughters' personality and psychopathology. Mothers and fathers were tested with the Temperament Character Inventory. Their daughters were assessed with the following: Temperament and Character Inventory, Eating Disorder Inventory-2, Symptom Checklist-90, Parental Bonding Instrument, Attachment Style Questionnaire, and Family Assessment Device. Daughters' personality traits and psychopathology scores were compared between clusters. Daughters' features were related to those of their parents. Explosive/adventurous mothers were found to relate to their daughters' borderline personality profile and more severe interoceptive awareness. Mothers' immaturity was correlated to their daughters' higher character immaturity, inadequacy, and depressive feelings. Fathers who were explosive/methodic correlated with their daughters' character immaturity, severe eating, and general psychopathology. Fathers' character immaturity only marginally related to their daughters' specific features. Both parents' temperament clusters and mothers' character clusters related to patients' personality and eating psychopathology. The cluster approach to personality-related dynamics of families with an individual affected by an eating disorder expands the knowledge on the relationship between parents' characteristics and daughters' illness, suggesting complex and unique relationships correlating parents' personality traits to their daughters' disorder.

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

    SciTech Connect

    Welsh, P.A.

    1995-12-31

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

  6. Complementary system for long term measurements of radon exhalation rate from soil

    SciTech Connect

    Mazur, J.; Kozak, K.

    2014-02-15

    A special set-up for continuous measurements of radon exhalation rate from soil is presented. It was constructed at Laboratory of Radiometric Expertise, Institute of Nuclear Physics Polish Academy of Sciences (IFJ PAN), Krakow, Poland. Radon exhalation rate was determined using the AlphaGUARD PQ2000 PRO (Genitron) radon monitor together with a special accumulation container which was put on the soil surface during the measurement. A special automatic device was built and used to raise and lower back onto the ground the accumulation container. The time of raising and putting down the container was controlled by an electronic timer. This set-up made it possible to perform 4–6 automatic measurements a day. Besides, some additional soil and meteorological parameters were continuously monitored. In this way, the diurnal and seasonal variability of radon exhalation rate from soil can be studied as well as its dependence on soil properties and meteorological conditions.

  7. Complementary system for long term measurements of radon exhalation rate from soil.

    PubMed

    Mazur, J; Kozak, K

    2014-02-01

    A special set-up for continuous measurements of radon exhalation rate from soil is presented. It was constructed at Laboratory of Radiometric Expertise, Institute of Nuclear Physics Polish Academy of Sciences (IFJ PAN), Krakow, Poland. Radon exhalation rate was determined using the AlphaGUARD PQ2000 PRO (Genitron) radon monitor together with a special accumulation container which was put on the soil surface during the measurement. A special automatic device was built and used to raise and lower back onto the ground the accumulation container. The time of raising and putting down the container was controlled by an electronic timer. This set-up made it possible to perform 4-6 automatic measurements a day. Besides, some additional soil and meteorological parameters were continuously monitored. In this way, the diurnal and seasonal variability of radon exhalation rate from soil can be studied as well as its dependence on soil properties and meteorological conditions. PMID:24593340

  8. Complementary system for long term measurements of radon exhalation rate from soil

    NASA Astrophysics Data System (ADS)

    Mazur, J.; Kozak, K.

    2014-02-01

    A special set-up for continuous measurements of radon exhalation rate from soil is presented. It was constructed at Laboratory of Radiometric Expertise, Institute of Nuclear Physics Polish Academy of Sciences (IFJ PAN), Krakow, Poland. Radon exhalation rate was determined using the AlphaGUARD PQ2000 PRO (Genitron) radon monitor together with a special accumulation container which was put on the soil surface during the measurement. A special automatic device was built and used to raise and lower back onto the ground the accumulation container. The time of raising and putting down the container was controlled by an electronic timer. This set-up made it possible to perform 4-6 automatic measurements a day. Besides, some additional soil and meteorological parameters were continuously monitored. In this way, the diurnal and seasonal variability of radon exhalation rate from soil can be studied as well as its dependence on soil properties and meteorological conditions.

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

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

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

  10. Comparative Measurements of Radon Concentration in Soil Using Passive and Active Methods in High Level Natural Radiation Area (HLNRA) of Ramsar

    PubMed Central

    Amanat, B; Kardan, M R; Faghihi, R; Hosseini Pooya, S M

    2013-01-01

    Background: Radon and its daughters are amongst the most important sources of natural exposure in the world. Soil is one of the significant sources of radon/thoron due to both radium and thorium so that the emanated thoron from it may cause increased uncertainties in radon measurements. Recently, a diffusion chamber has been designed and optimized for passive discriminative measurements of radon/thoron concentrations in soil. Objective: In order to evaluate the capability of the passive method, some comparative measurements (with active methods) have been performed. Method: The method is based upon measurements by a diffusion chamber, including two Lexan polycarbonate SSNTDs, which can discriminate the emanated radon/thorn from the soil by delay method. The comparative measurements have been done in ten selected points of HLNRA of Ramsar in Iran. The linear regression and correlation between the results of two methods have been studied. Results: The results show that the radon concentrations are within the range of 12.1 to 165 kBq/m3 values. The correlation between the results of active and passive methods was measured by 0.99 value. As well, the thoron concentrations have been measured between 1.9 to 29.5 kBq/m3 values at the points. Conclusion: The sensitivity as well as the strong correlation with active measurements shows that the new low-cost passive method is appropriate for accurate seasonal measurements of radon and thoron concentration in soil. PMID:25505760

  11. 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.

  12. Spatio-temporal variations of soil radon patterns around the Sea of Marmara

    NASA Astrophysics Data System (ADS)

    Passarelli, Luigi; Seyis, Cemil; Woith, Heiko

    2016-04-01

    Typically, the noble gas radon displays cyclic daily (S1), semidiurnal (S2) as well as seasonal variations in geological environments like soil air, groundwater, rock, caves, and tunnels. But there are also cases where theses cycles are absent. We present examples from a radon monitoring network of 21 sites around the Sea of Marmara. The works were carried out in the frame of MARsite, a project related to the EU supersite initiative (MARsite has received funding from the European Union's Seventh Programme for research, technological development and demonstration under grant agreement No 308417). Alpha-meters from the Canadian company alpha-nuclear are used to measure the radon concentration in counts per 15 minutes at a depth of 80 cm. The long-term average radon concentrations at 21 sites vary between 35 and 1,000 counts per 15 minutes. Typical seasonal variations are absent at more than 6 sites. Sites with seasonal variations have radon minima usually during winter (December to April), radon maxima during summer months (June to October). We carefully investigated radon time series for all the monitoring stations. We find that at some sites the empirical distribution of radon counts is clearly bimodal and in other bimodality is absent. In those stations we analysed the time series in different time intervals in order to highlight seasonal periodicity in the radon emission. The empirical distributions obtained by time-windowing of the radon signals results to be statistically different one another after applying a Kolmogorov-Smirnov test at significance level of 0.1. Usually the maxima in radon emission occur in summer time but, interestingly enough, two sites are characterized by radon maxima in winter periods. We further investigate the radon signals seeking for smaller scale periodicity. We calculated Fourier spectra of all 21 sites. Daily cycles are absent at 6 sites which is an unusual phenomenon. Daily cycles may disappear, if the local system is heavily

  13. Mapping Submarine Groundwater Discharge Using Radon and Geographic Information Systems

    NASA Astrophysics Data System (ADS)

    Grant, C. M.; Rapaglia, J. P.

    2013-05-01

    Fresh submarine groundwater discharge (SGD), which is likely the fraction of SGD most important for nutrient flux into the coastal zone, is driven by terrestrial hydraulic gradients. It is, therefore, logical to utilize this information in the search for SGD. The increased precision of digital elevation models (DEM) combined with the utility of geographic information systems (GIS) enables the researcher to pinpoint flow accumulation. ArcGIS 10 was used to find and quantify flow accumulation in Port Jefferson Harbor, NY and the Niantic River, CT. Both Port Jefferson and the Niantic are of similar geology being formed by glacial moraines marked by high hydraulic conductivity. In Port Jefferson, high flow was found in the southwestern and southeastern corners of the harbor. Here folds in land elevation focused water into the corners of the harbor. In the Niantic River flow accumulation was determined near anomalously high pockets of Nitrate-Nitrogen found previous to this study. Meanwhile, although radon has been used extensively as a tracer for SGD, few studies have used radon to map it. Radon was used to investigate groundwater seepage in both locations. An in-air radon monitor, RAD7, modified with a RAD Aqua, was used in a closed loop system to detect continuous Rn levels while steaming along the coastline. It was found that in areas with high flow accumulation as determined by the GIS analysis, Rn levels were similarly elevated (636 Bq/m3). This work complements research undertaken in the Baltic Sea, Germany, although the relatively smaller spatial scale of this study was, perhaps, more useful in matching radon activities and flow accumulation. While it may not be financially or logistically sensible to do extensive radon studies, this method of mapping fresh SGD may help researchers find the preverbal needle in a haystack.

  14. Epistemic assessment of radon level of offices in Hong Kong

    NASA Astrophysics Data System (ADS)

    Wong, L. T.; Mui, K. W.; Law, K. Y.; Hui, P. S.

    People spend most of their life working indoors. Human exposure to various air pollutants changed its importance in nature from outdoor to indoor. As some of the pollutant sources basically originate from the building envelope that could not be removed or is costly to mitigate, the remaining questions are: how the indoor air quality (IAQ) is monitored and how the information could be used for the environmental control system to achieve the best air quality delivery. Indoor radon level could be measured with a number of sampling approaches and used to determine the acceptance of an IAQ with respect to certain exposure limits. In determining the acceptable IAQ of a space, this study proposes that the measured indoor radon level must be accompanied with the confidence levels of the assessment. Radon levels in Hong Kong offices were studied by a cross-sectional measurement in 216 typical offices and a year-round longitudinal measurement in one office. The results showed that 96.5% (94.0-99.0% at 95% confidence interval) and 98.6% (97.0% to >99.9% at 95% confidence interval) of the sampled offices would satisfy action radon levels of 150 and 200 Bq m -3, respectively. The same results were then used to quantify the prior knowledge on radon level distributions of an office and the probable errors of the adopted sampling schemes. This study proposes an epistemic approach, with the prior knowledge and a sample test result, to assess the acceptance against an action radon level of an office in Hong Kong. With the certainty of the test results determined for judgmental purposes, it is possible to apply the method to an office for follow-up tests of acceptance.

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

    PubMed

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

    2003-01-01

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

  16. 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.

  17. 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...

  18. The Impact of Mother-Daughter Communication on Daughter's Sexual Knowledge, Behavior and Contraceptive Use.

    ERIC Educational Resources Information Center

    Fox, Greer Litton; Inazu, Judith K.

    Family background variables such as race, religion, and gender of household head emerged as significant predictors of communication about sex in interviews conducted with a sample of mothers and teenage daughters. A suprising finding was a strong positive association between family religion and early sexual communication, although this may reflect…

  19. Involvement of growth factors and their receptors in radon-induced rat lung tumors

    SciTech Connect

    Leung, F.C.; Dagle, G.E.; Cross, F.T.

    1992-12-31

    In this paper we examine the role of growth factors (GF) and their receptors (GFR) in radon-induced rat lung tumors. Inhalation exposure of radon and its daughters induced lung tumors in rats, but the molecule/cellular mechanisms are not known. Recent evidence suggests that GF/GFR play a critical role in the growth and development of lung cancer in humans and animals. We have developed immunocytochemical methods for identifying sites of production and action of GF/GFR at the cellular level; for example, the avidin-biotin horseradish peroxidase technique. In radon-induced rat epidermoid carcinomas, epidermal growth factor (EGF), EGF-receptors (EGF-R), transforming growth factor alpha (TGF-{alpha}), and bombesin were found to be abnormally expressed. These abnormal expressions, mainly associated with epidermoid carcinomas of the lung, were not found in any other lung tumor types. Our data suggest that EGF, EGF-R, TGF-{alpha}, and bombesin are involved in radon oncogenesis in rat lungs, especially in epidermoid carcinomas, possibly through the autocrine/paracrine pathway.

  20. RADON AND PROGENY ALPHA-PARTICLE ENERGY ANALYSIS USING NUCLEAR TRACK METHODOLOGY

    SciTech Connect

    Espinosa Garcia, Guillermo; Golzarri y Moreno, Dr. Jose Ignacio; Bogard, James S

    2008-01-01

    A preliminary procedure for alpha energy analysis of radon and progeny using Nuclear Track Methodology (NTM) is described in this paper. The method is based on the relationship between alpha-particle energies deposited in polycarbonate material (CR-39) and the track size developed after a well-established chemical etching process. Track geometry, defined by parameters such as major or minor diameters, track area and overall track length, is shown to correlate with alpha-particle energy over the range 6.00 MeV (218Po) to 7.69 MeV (214Po). Track features are measured and the data analyzed automatically using a digital imaging system and commercial PC software. Examination of particle track diameters in CR-39 exposed to environmental radon reveals a multi-modal distribution. Locations of the maxima in this distribution are highly correlated with alpha particle energies of radon daughters, and the distributions are sufficiently resolved to identify the radioisotopes. This method can be useful for estimating the radiation dose from indoor exposure to radon and its progeny.

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

    SciTech Connect

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

    2008-07-01

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

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

    PubMed

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

    2014-07-01

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

  3. Metakaolin as a radon retardant from concrete.

    PubMed

    Lau, B M F; Balendran, R V; Yu, K N

    2003-01-01

    Granite aggregates are known to be the radon source in concrete. Recently, metakaolin has been introduced as a partial substitution of Portland cement to produce high strength concrete. It can effectively reduce the porosity of both the matrix and the aggregate/paste transition zone, which suggests its ability to retard radon emission from concrete aggregates. In the present work, radon exhalation rates from concrete cubes substituted with metakaolin were measured using charcoal canisters and gamma spectroscopy, and were considerably lower than those from normal concrete, by about 30%. The indoor radon concentration reduction is estimated as approximately 9 Bq m(-3) calculated using a room model, causing a 30% reduction in the indoor radon concentration and the corresponding radon dose. Therefore, metakaolin is a simple material to reduce the indoor radon concentration and the radon dose.

  4. 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. PMID:27155259

  5. Feminist attitudes and mother-daughter relationships in adolescence.

    PubMed

    Notar, M; McDaniel, S A

    1986-01-01

    In spite of the growing amount of research on women's issues, there are few empirical studies of mother-daughter relationships, and almost none on the effects of the major women's movement of our times on relationships between mothers and daughters. In this study of late adolescent daughters' perceptions of their relationships with their mothers, two alternative hypotheses are examined: (1) feminism, with its emphasis on bonding among women, strengthens relations between adolescent daughters and their mothers, or (2) feminism as a force of social change, both attitudinal and behavioral, weakens the adolescent daughter-mother relationship. Based on 102 questionnaires completed by university-age women in the winter of 1983, it was found that the majority of daughters who have a good relationship with their mothers see both themselves and their mothers as feminist. However, these daughters do not attribute their positive mother-daughter relationship explicitly to feminism. For the minority of daughters who claim to have a poor relationship with their mothers, they attribute the problems to feminism.

  6. Analysis of radon and radon progeny in residences: factors that affect their amounts and methods of reduction. Master's thesis

    SciTech Connect

    Little, D.R.

    1985-03-01

    The effectiveness of using an electrostatic precipitator as a means for reducing harmful levels of radon progeny in the home was evaluated. A commercially available precipitator, manufactured by the Honeywell Corporation, was used during the course of the study. The specific model used was the Honeywell Electronic Air Cleaner model number F50A1009. Daughter concentrations were measured by the modified Tsivoglou method. Samples were collected on a 2-inch millipore filter and alpha emissions were measured with a ZnS(Ag) scintillator. A sample collection time of 5 minutes was used. Sample counting intervals of 2-5, 6-20, and 21-30 minutes after sample collection were used. During this study air samples were made using the blower fan and filters alone with no power to the electrostatic precipitator, and with the electrostatic precipitator energized. The reduction in the working level as a result of using the blower fans and filters only was 75%. With the electrostatic precipitator energized, the reduction level rose to 90%. It is therefore concluded that the electrostatic precipitator is an effective means for reducing radon progeny concentrations in the home.

  7. Radon in soil gas at the Ravne fault in NW Slovenia

    NASA Astrophysics Data System (ADS)

    Vaupotič, J.; Gregorič, A.; Kobal, I.; Žvab, P.; Kozak, K.; Mazur, J.; Kochowska, E.; Grządziel, D.

    2009-04-01

    The Ravne tectonic fault in north-west Slovenia is one of the faults in this region, responsible for the elevated seismic activity at the Italian-Slovene border. At 18 points along five profiles, four perpendicular and one parallel to the fault, the following measurements have been carried out: radon activity concentration in soil gas, using an AlphaGuard radon monitor and alpha scintillation cells, radon exhalation rate and soil permeability, using the AlphaGuard equipment, and gamma dose rate, using GammaTracer. The ranges of the obtained results are as follows: (0.9-33.9) kBq m-3 for radon concentration, (1.1-41.9) mBq m-2 s-1 for radon exhalation rate, (0.5-7.4)Ã-10-13 m2 for soil permeability, and (86-138) nSv h-1 for gamma dose rate. Dependence of radon concentration and exhalation rate on the distance from the fault has been sought but not univocally understood. At three perpendicular profiles, values of both parameters increase when approaching the fault, while the opposite was found at one. At the very centre of the fault, both values were lowest at one profile, but at another, radon activity was highest and exhalation rate lowest. At all points, permeability may be considered as medium and gamma dose rate as similar to other places in Slovenia.

  8. Calculating flux to predict future cave radon concentrations.

    PubMed

    Rowberry, Matt D; Martí, Xavi; Frontera, Carlos; Van De Wiel, Marco J; Briestenský, Miloš

    2016-06-01

    along crustal discontinuities and its subsequent exhalation into the atmosphere. Furthermore, as it is possible to supply the model with continuous data, future research will focus on establishing a series of underground monitoring sites with the aim of generating the first real time global radon flux maps. PMID:26950394

  9. [The radon risk in Lombardy].

    PubMed

    Facchini, U; Sesana, L; Agostoni, G; Testa, V

    1997-10-01

    We investigated the geographical distribution of lung cancer mortality rates in some Italian regions, Lombardy and Emilia-Romagna in particular, where the investigation was mainly focused on the risk related to the presence of radon inside dwelling-houses. We referred to the death certificates provided by the Central Institute of Statistics (ISTAT) relative to the years 1980-1988 to calculate the relevant mortality rates. Mortality rates appear higher in some northern than in southern regions and in the islands and also (> a factor of 10) in the male than in the female population; the mortality rates in the male population exhibit a linear correlation with past cigarette smoking. The death rates in the male population (age range: 35-64 years) in northern Italy average 100 events/100,000 inhabitants, but several local health centers in Lombardy at the foot of the Alpine range, north of the Po River, have mortality rates over 50% higher than estimated rates. We considered radon exposure in Lombardy dwelling-houses. The Alps are rich in granite rocks, with 50-150 Bq/kg uranium concentrations, which produce the sediments, sands and gravels making the ground of the Lombardy plain. A recent survey of indoor radon exposure levels showed average values around 100 Bq/m3. The National Academy of Sciences (Washington, DC) has presented a formula to calculate the relative risk of lung cancer related to radon exposure during a lifetime. When this model was applied to excess events in Lombardy, acceptable agreement was found with the assumption that excess deaths are ascribable to higher radon exposure levels. We also compared Lombardy with Emilia-Romagna where the sediments and soil in the plain come from the Apennine range where calcareous rocks have low uranium content. Radon exposure levels in Emilia-Romagna were around 50 Bq/m3 and the radon risk factor in this region is therefore not particularly significant.

  10. 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.

  11. 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...

  12. 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.

  13. An overview of radon research in Canada.

    PubMed

    Chen, Jing; Whyte, Jeff; Ford, Ken

    2015-11-01

    Based on new scientific information and broad public consultation, the Government of Canada updated the guideline for exposure to indoor radon and launched a multi-year radon programme in 2007. Major achievements in radon research accomplished in the past 7 y are highlighted here.

  14. 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)

  15. 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…

  16. 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…

  17. 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).

  18. Radon levels can be predicted

    NASA Astrophysics Data System (ADS)

    Wainger, Lisa A.

    Scientists doing a yearlong study of radon levels in houses have identified several major factors that affect concentrations and have developed a method for predicting indoor radon levels before a house is built. Douglas Mose and George Mushrush (George Mason University, Fairfax, Va.) studied 1500 homes in northern Virginia and central Maryland near Washington, D.C.Radon is a radioactive decay product of uranium that occurs in many rock types. The gas can accumulate in buildings and pose a serious health hazard. Results from the Washington-area study show that ˜35% of the houses had average yearly radon concentrations above 4 pico-Curies per liter (pCi/L), the level at which the Environmental Protection Agency (EPA) suggests that a homeowner should take steps to reduce radon concentrations. At a level of 4-10 pCi/L an estimated 13-120 lung cancer deaths would be expected for every 1000 people exposed. Such a risk is comparable to having 200 chest X rays per year, according to EPA statistics.

  19. 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.

  20. A Radon Progeny Deposition Model

    NASA Astrophysics Data System (ADS)

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

    2011-04-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222Rn) 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 210Pb 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.

  1. 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.

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

    PubMed

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

    2012-04-01

    This paper provides evaluations of the radiometric behavior and exhalation patterns of radon gas in decorative and dimension stones explored in the Brazilian states of Minas Gerais and Espírito Santo, given the importance of determining radon gas concentrations in human-inhabited environments. A total of 10 silicate rock types were studied, featuring different petrographic/petrophysical characteristics given by seven magmatic rocks (three of which are granitic pegmatites) and three metamorphic rocks. The study, comprising radiometric data of U and monitoring of (222)Rn gas exhalation, shows a strong correlation between petrographic parameters and the physical properties of rocks. U levels ranged between 2.9 and 37 ppm, revealing a good coherence between the presence and the absence of radioactive element-bearing accessory minerals for each rock type. The rate of radon exhalation from the stones is related to the petrographic/petrophysical features of each material. By comparing the (222)Rn level generated by a rock to the amount effectively emanated by it, the rate of emanated gas proves to be insignificant; also, a rock that produces more Rn will not always emanate more. Simulations performed to estimate the radon levels inside residences or any given indoor environment showed that nine samples attained values below the 4 pCi/L EPA limit, whereas one was above that limit. PMID:22244194

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

    PubMed

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

    2012-04-01

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

  4. Radon measurements and analysis for central Pennsylvania counties having elevated radon levels.

    PubMed

    Distenfeld, C; Distenfeld, J; Distenfeld, L

    2001-05-01

    The U.S. EPA identified South Central Pennsylvania as a region having elevated radon levels. The thnist of this paper is to examine in some detail the TCS Industries, Inc., data base for eight Central Pennsylvania counties having a combined population of about 1.7 million people, which is 14% of the state population. TCS has been making and analyzing radon measurements since 1986. During the period 1986 to 1999 more than 125,000 measurements were recorded in the TCS data base. The data consisted of analyzed results from four subsets. Results were from mail order charcoal canisters, bulk orders from RMP certified companies for their placement, wholesales to retail vendors, and also direct home placement of canisters, track detectors, and continuous radon monitors. The data base for the eight South Central Pennsylvania counties for tile 13-y period consists of more than 27,000 screening measurements from non-duplicated addresses. The results were assembled into three studies. The locations of tile measurements were converted into individual latitude and longitude values. The data were divided into four blocks of concentrations from 740 Bq m(-3) to over 4,440 Bq m(-3). The data were plotted on computer generated maps for South Central Pennsylvania. The plots indicated both hot spots and regions of relatively uniform chronic levels of 740 to 1,480 Bq m(-3). An average value of the basement to first floor concentrations ratio was constructed from measurements made by TCS for real estate purposes. The ratio represents 1,608 sets of simultaneous measurements of basements and first floor radon values above 37 Bq m(-3). The measurements were made by trained personnel performed under tile EPA protocol for closed house conditions. The ratio was 2.3 at 1 standard deviation of 0.05 of the mean. A third study assembled all of the data into first floor radon concentrations and separately for addresses with only basement values. The average concentration data within each of the

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

    SciTech Connect

    Osborne, M.; Harrison, J.

    1992-01-01

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

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

    PubMed

    Franci, Daniele; Aureli, Tommaso

    2014-12-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  8. Thoron detection with an active Radon exposure meter—First results

    SciTech Connect

    Irlinger, J. Wielunski, M.; Rühm, W.

    2014-02-15

    For state-of-the-art discrimination of Radon and Thoron several measurement techniques can be used, such as active sampling, electrostatic collection, delayed coincidence method, and alpha-particle-spectroscopy. However, most of the devices available are bulky and show high power consumption, rendering them unfeasible for personal exposition monitoring. Based on a Radon exposure meter previously realized at the Helmholtz Center Munich (HMGU), a new electronic prototype for Radon/Thoron monitoring is currently being developed, which features small size and weight. Operating with pin-diode detectors, the low-power passive-sampling device can be used for continuous concentration measurements, employing alpha-particle-spectroscopy and coincidence event registration to distinguish decays originating either from Radon or Thoron isotopes and their decay products. In open geometry, preliminary calibration measurements suggest that one count per hour is produced by a 11 Bq m{sup −3} Radon atmosphere or by a 15 Bq m{sup −3} Thoron atmosphere. Future efforts will concentrate on measurements in mixed Radon/Thoron atmospheres.

  9. Thoron detection with an active Radon exposure meter--first results.

    PubMed

    Irlinger, J; Wielunski, M; Rühm, W

    2014-02-01

    For state-of-the-art discrimination of Radon and Thoron several measurement techniques can be used, such as active sampling, electrostatic collection, delayed coincidence method, and alpha-particle-spectroscopy. However, most of the devices available are bulky and show high power consumption, rendering them unfeasible for personal exposition monitoring. Based on a Radon exposure meter previously realized at the Helmholtz Center Munich (HMGU), a new electronic prototype for Radon/Thoron monitoring is currently being developed, which features small size and weight. Operating with pin-diode detectors, the low-power passive-sampling device can be used for continuous concentration measurements, employing alpha-particle-spectroscopy and coincidence event registration to distinguish decays originating either from Radon or Thoron isotopes and their decay products. In open geometry, preliminary calibration measurements suggest that one count per hour is produced by a 11 Bq m(-3) Radon atmosphere or by a 15 Bq m(-3) Thoron atmosphere. Future efforts will concentrate on measurements in mixed Radon/Thoron atmospheres. PMID:24593342

  10. Variations of soil radon concentrations along Chite fault in Aizawl district, Mizoram, India.

    PubMed

    Singh, Sanjay; Jaishi, Hari Jaishi; Tiwari, Raghavendra Prasad; Tiwari, Ramesh Chandra

    2014-11-01

    The present study concerns measurements of radon emissions from soil carried out during March to July 2013 at Chite fault in Aizawl district, Mizoram, India. In this study, continuous radon monitoring in soil was done by using LR-115 type II nuclear track detector (Kodak-Pathe, France make), and the exposed films were replaced weekly. A negative correlation coefficient (-0.47) between radon concentration and barometric pressure was found during the investigation period. The average radon concentration was observed to be 1785.71 Bq m(-3) with a standard deviation of 633.07 Bq m(-3). The maximum and minimum values of radon concentration during this period were found to be 3693.88 and 904.76 Bq m(-3), respectively. An anomalous increase in radon concentration was observed on 112th day (i.e. on 14 June 2013) during the investigation period just 1 d prior to the event of M 3.5, which occurred within 120-km distance from the monitoring site. PMID:24996920

  11. Winnipeg radon testing: comparison of test durations, effects of house characteristics, and efficacy of floor-drain seals.

    PubMed

    Warkentin, Pamela E M; Johnson, Harry M

    2015-04-01

    A research study has investigated the correlation of radon test data for three testing periods obtained in a set of 50 homes. The homes were part of the housing stock in a long-established subdivision in Winnipeg, Manitoba, for which it was initially hypothesized that a high percentage of homes had radon levels above the Canadian guideline. Co-linear tests, all commencing on the same date, were conducted over periods of 5 d, 30 d, and 91 d under closed building conditions during the 2009-10 heating season using electret ion radon detectors, supplemented in some instances by measurements with a continuous radon monitor. Radon levels in 33 of the 50 homes exceeded the Canadian radon guideline of 200 Bq m in 91-d tests. False-positive and false-negative analyses of the 5-d tests and 30-d tests were conducted relative to the 91-d tests in the respective homes. False positive/false negative analyses indicated that the short-term and the medium-term testing results reflected the results of the 91-d tests over 85% of the time. Precision testing of the radon data was carried out in accordance with quality assurance protocols. Correlation of a building construction survey with radon data indicated that earth-floor crawl spaces were common contributors to elevated radon levels. Testing was also done to measure the efficacy of a commercial brand of floor drain seal installed to lower radon levels, which resulted in an average radon reduction of 47% in homes without earth-floor crawl spaces. PMID:25706136

  12. Winnipeg radon testing: comparison of test durations, effects of house characteristics, and efficacy of floor-drain seals.

    PubMed

    Warkentin, Pamela E M; Johnson, Harry M

    2015-04-01

    A research study has investigated the correlation of radon test data for three testing periods obtained in a set of 50 homes. The homes were part of the housing stock in a long-established subdivision in Winnipeg, Manitoba, for which it was initially hypothesized that a high percentage of homes had radon levels above the Canadian guideline. Co-linear tests, all commencing on the same date, were conducted over periods of 5 d, 30 d, and 91 d under closed building conditions during the 2009-10 heating season using electret ion radon detectors, supplemented in some instances by measurements with a continuous radon monitor. Radon levels in 33 of the 50 homes exceeded the Canadian radon guideline of 200 Bq m in 91-d tests. False-positive and false-negative analyses of the 5-d tests and 30-d tests were conducted relative to the 91-d tests in the respective homes. False positive/false negative analyses indicated that the short-term and the medium-term testing results reflected the results of the 91-d tests over 85% of the time. Precision testing of the radon data was carried out in accordance with quality assurance protocols. Correlation of a building construction survey with radon data indicated that earth-floor crawl spaces were common contributors to elevated radon levels. Testing was also done to measure the efficacy of a commercial brand of floor drain seal installed to lower radon levels, which resulted in an average radon reduction of 47% in homes without earth-floor crawl spaces.

  13. Results from the Lunar Prospector Alpha Particle Spectrometer: Detection of Radon-222 Over Craters Aristarchus and Kepler

    NASA Astrophysics Data System (ADS)

    Lawson, S. L.; Feldman, W. C.; Lawrence, D. J.; Moore, K. R.; Belian, R. D.; Maurice, S.; Binder, A. B.

    2001-11-01

    The Lunar Prospector Alpha Particle Spectrometer (LP APS) searched for lunar surface gas release events and mapped their distribution by detecting alpha particles produced by the decay of gaseous radon-222 (5.5 MeV, 3.8 day half-life), solid polonium-218 (6.0 MeV, 3 minute half-life), and solid polonium-210 (5.3 MeV, 138 day half-life, but held up in production by the 21 year half-life of lead-210). These three nuclides are radioactive daughters from the decay of uranium-238. Radon reaches the lunar surface either at areas of high soil porosity or where fissures release the trapped gases in which radon is entrained. We have examined APS data within +/- 45 degrees of the equator acquired during periods of low interplanetary alpha particle flux. The spectra were summed over all LP mapping cycles when the instrument was turned on (approximately 229 days over 16 months). To yield lunar alpha particle maps, we summed over a 0.2 MeV energy range centered on each of the three alpha particle energies noted above. The LP APS found only a faint indication of alpha particles resulting from the decay of polonium-218 and only a marginal detection of alpha particles from polonium-210. However, our radon-222 alpha particle map indicates that radon gas is presently emanating from the vicinity of craters Aristarchus and Kepler. The LP gamma-ray spectrometer, which effectively has significantly higher spatial resolution than the APS, identified thorium enrichments at these two craters. Thorium and uranium are both incompatible elements whose lunar surface abundances are highly correlated; thus, it is likely that the radon-222 alpha particles measured using the LP APS originate from Kepler and Aristarchus. Our detection of radon over Aristarchus is consistent with the results of the Apollo 15 APS.

  14. The Wilson Report: Moms, Dads, Daughters and Sports.

    ERIC Educational Resources Information Center

    Diagnostic Research Inc., Los Angeles, CA.

    A report is given on the results of a nationwide survey (N=1,004 parents, 513 daughters) studying the influence of parents and family factors on girls' participation in sports. A large majority of parents regarded participation in sports as an important part of their daughters' development, and that it is as important for girls to be involved in…

  15. Incest and Its Meaning: The Perspectives of Fathers and Daughters.

    ERIC Educational Resources Information Center

    Phelan, Patricia

    1995-01-01

    Interviews with 40 fathers and stepfathers and 44 biologic daughters and stepdaughters involved in incestuous activity revealed their recollection of events, their thoughts, and interpretations. Fathers' thoughts were dominated by themes of sexual gratification, control, power, anger, and rights and responsibilities; daughters reported disbelief,…

  16. Adolescents with Nonresident Fathers: Are Daughters More Disadvantaged than Sons?

    ERIC Educational Resources Information Center

    Mitchell, Katherine Stamps; Booth, Alan; King, Valarie

    2009-01-01

    This study examined sons' and daughters' involvement with nonresident fathers and associated outcomes (N = 4,663). Results indicated that sons and daughters reported equal involvement with nonresident fathers on most measures of father investment, although sons reported more overnight visits, sports, and movies and feeling closer to their fathers…

  17. Posttraumatic Stress in Women with Breast Cancer and Their Daughters.

    ERIC Educational Resources Information Center

    Boyer, Bret A.; Bubel, Denise; Jacobs, Sheri R.; Knolls, Michelle L.; Harwell, Valerie D.; Goscicka, Magdalena; Keegan, Anne

    2002-01-01

    Twenty-one percent of the surveyed women (N=133) with cancer and 13% of their daughters (N=64) reported symptoms of posttraumatic stress disorder (PTSD). Prevalence of PTSD symptoms in daughters appears comparable to women with breast cancer. Discusses intergenerational patterns in reaction to breast cancer. (JDM)

  18. [Mother-daughter relationship as a motive for "late" pregnancy].

    PubMed

    Langer, M

    1990-01-01

    Two cases of elder multiparae are presented, who conceived a "late" pregnancy subsequent to their daughters' pregnancies. Both women shared specific pregnancy motives, which stemmed from unresolved conflicts in the mother-daughter--relationship. A second cluster of motives focuses around the wish to compensate for the perceived loss of youthfulness and reproductive ability or the loss of a partner in a symbiotic relationship.

  19. Alerting patients to the risk of radon

    SciTech Connect

    Bell, R.T.; Stewart, K.M.

    1993-06-01

    The potential lung cancer risk from exposure to radon gas and the development of appropriate public health policy have been the subject of much discussion for several years. The American Lung Association has taken a leading role in educating the public on radon and other environmental hazards. This article presents background on radon, including the issues of risk assessment and policy development; reviews the current understanding of the hazards of exposure and the scope of the problem; describes how to test for radon; and discusses how to decrease radon levels.

  20. Indoor radon survey in Visegrad countries.

    PubMed

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

    2016-04-01

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

  1. Simulation of Radon Transport in Geothermal Reservoirs

    SciTech Connect

    Semprini, Lewis; Kruger, Paul

    1983-12-15

    Numerical simulation of radon transport is a useful adjunct in the study of radon as an in situ tracer of hydrodynamic and thermodynamic numerical model has been developed to assist in the interpretation of field experiments. The model simulates transient response of radon concentration in wellhead geofluid as a function of prevailing reservoir conditions. The radon simulation model has been used to simulate radon concentration response during production drawdown and two flowrate transient tests in vapor-dominated systems. Comparison of model simulation with experimental data from field tests provides insight in the analysis of reservoir phenomena such as propagation of boiling fronts, and estimates of reservoir properties of porosity and permeability thickness.

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

    PubMed

    Guo, Lu; Zhang, Lei; Guo, Qiuju

    2016-06-01

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

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. New methods of energy efficient radon mitigation

    SciTech Connect

    Fisk, W.J.; Wooley, J.; Gadgil, A.J.

    1995-05-01

    Two new radon mitigation techniques are introduced and their evaluation in a field study complemented by numerical model predictions is described. Based on numerical predictions, installation of a sub gravel membrane at the study site resulted in a factor of 2 reduction in indoor radon concentrations. Experimental data indicated that installation of {open_quotes}short-circuit{close_quotes} pipes extending between the subslab gravel and outdoors caused an additional factor of 2 decrease in the radon concentration. Consequently, the combination of these two passive radon mitigation features, called the membrane and short-circuit (MASC) technique, was associated with a factor of 4 reduction in indoor radon concentration. The energy-efficient active radon mitigation method, called efficient active subslab pressurization (EASP), required only 20% of the fan energy of conventional active subslab depressurization and reduced the indoor radon concentration by approximately a factor of 15, including the numerically-predicted impact of the sub-gravel membrane.

  8. Characterizing the source of radon indoors

    SciTech Connect

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

    1983-09-01

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

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

    SciTech Connect

    George, A. C.

    2008-08-07

    1950's onwards a variety of radon measuring instruments were developed to assess the radon and radon decay product exposure to underground miners, workers at contaminated sites with uranium and radium tailings and to the general public in residential buildings. In the last twenty years, new instruments and methods were developed to measure radon by using grab, integrating and continuous modes of sampling. The most common are scintillation cell monitors, activated carbon collectors, electret ionization chambers, alpha track detectors, pulse and current ionization chambers and solid-state alpha detectors.

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

    NASA Astrophysics Data System (ADS)

    George, A. C.

    2008-08-01

    onwards a variety of radon measuring instruments were developed to assess the radon and radon decay product exposure to underground miners, workers at contaminated sites with uranium and radium tailings and to the general public in residential buildings. In the last twenty years, new instruments and methods were developed to measure radon by using grab, integrating and continuous modes of sampling. The most common are scintillation cell monitors, activated carbon collectors, electret ionization chambers, alpha track detectors, pulse and current ionization chambers and solid-state alpha detectors.

  11. 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.

  12. Removal and deposition efficiencies of the long-lived 222Rn daughters during etching of germanium surfaces

    NASA Astrophysics Data System (ADS)

    Zuzel, G.; Wójcik, M.; Majorovits, B.; Lampert, M. O.; Wendling, P.

    2012-06-01

    Removal and deposition efficiencies of the long-lived 222Rn daughters during etching from and onto surfaces of standard and high purity germanium were investigated. The standard etching procedure of Canberra-France used during production of high purity n-type germanium diodes was applied to germanium discs, which have been exposed earlier to a strong radon source for deposition of its progenies. An uncontaminated sample was etched in a solution containing 210Pb, 210Bi and 210Po. All isotopes were measured before and after etching with appropriate detectors. In contrast to copper and stainless steel, they were removed from germanium very efficiently. However, the reverse process was also observed. Considerable amounts of radioactive lead, bismuth and polonium isotopes present initially in the artificially polluted etchant were transferred to the clean high purity surface during processing of the sample.

  13. Soil radon as a possible earthquake precursor: Preliminary results from Ileia (Greece)

    NASA Astrophysics Data System (ADS)

    Petraki, Ermioni; Nikolopoulos, Dimitrios; Louizi, Anna; Zisos, Athanasios

    2010-05-01

    Radon (222Rn) is a naturally occurring radioactive gas which is directly produced by the decay of the 238U series. It is significant for the studies of Earth, in hydrogeology and atmosphere. Radon is used as a trace gas due to the long half-life (3.82-days) which allows migration at long distances. In addition, it is an alpha emitter, fact which enables detection of low levels of radon. Anomalies of radon impending earthquakes of a variety of magnitudes have been observed in soil gas, ground- and thermal-waters and in underground tunnels. Increasing is the scientific interest in this field during the last two years. However, the majority of the published papers refer to data of rather long time intervals between sequential measurements (~2-4 weeks).On the other hand, it is justified, both on laboratory and geophysical scale, that when a heterogeneous material is strained acoustic and electromagnetic (EM) emissions occur in a wide frequency spectrum, ranging from very low to very high frequencies. These emissions are considered as precursors of general fracture. In the search of soil radon as a possible earthquake precursor, a station for quick and continuous monitoring of soil radon has been installed in a very active tectonic site in Greece (Ileia, Peloponnese, SW Greece). The monitoring site is Kardamas Ileias, located 3 km south from Amaliada which is the second highly populated city. The instrumental and felt seismicity of Ileia is dominated by extensional active seismicity structures (e.g. Alfeios, Neda, Melpeia, Kiparissia-Aetos) and has shown more than 600 earthquakes of magnitude greater than 4.0 R in the last 100 years. Two earthquakes were very destructive (5.8 R on 26/3/93 and 6.8 R on 8/6/08 respectively). The station consists of a high precision active instrument (Alpha Guard-AG, Genitron Ltd.), equipped with an appropriate unit designed for pumping and measurement of radon in soil gas (Soil gas Unit, Genitron Ltd.). Soil radon is continuously pumped

  14. Radon mitigation survey among New York State residents living in high radon homes

    SciTech Connect

    Wang, Y.; Ju, C.; Stark, A.D.; Teresi, N.

    1999-10-01

    In order to evaluate the effectiveness of New York State Department of Health's efforts to increase public awareness about radon risk and to promote radon testing and mitigation in compliance with EPA's guideline, a statewide radon mitigation survey was conducted between September 1995 and January 1996 among New York State residents whose homes had radon levels equal to or greater than 148 Bq m{sup {minus}3} on the first floor (or above) living areas. The survey found that about 60% of 1,113 participants had taken actions for radon mitigation. The percentage of respondents who took actions to reduce radon levels in their homes increased with increasing education level as well as household income level. The method of installing a powered system to provide more ventilation was a more effective mitigation method than opening windows/doors or sealing cracks/openings in the basement. Mitigation performed by contractors was more effective in reducing radon levels than mitigation performed by residents. The reasons for performing radon mitigation given by the majority of respondents were those strongly related to radon health risk. High home radon level was an important motivational factor to stimulate radon mitigation. On the other hand, the cost of radon mitigation was a major barrier in decision making for performing radon mitigation and for selecting mitigation measures.

  15. Assessing the deposition of radon progeny from a uranium glass necklace.

    PubMed

    Hansen, M F; Moss, G R

    2015-06-01

    Could jewellery made from uranium glass beads pose an increased risk to skin cancer? The literature Eatough (Alpha-particle dosimetry for the basal layer of the skin and the radon progeny (218)Po and (214)Po. Phys. Med. Biol. 1997; 42: 1899-1911.) suggests that the alphas from the short-lived radon daughters, (218)Po and (214)Po, may reach the basal layer of the epidermis, which is believed to be important in the induction of skin cancers. The deposition of the alphas from the (218)Po and (214)Po daughters was investigated using PADC detector material. The expectation would be that no alpha particles would penetrate through the dead skin layer, assuming the average of 70 microns used in radiation protection, but the skin around the collar bone could potentially be thinner than the assumed average. It should be noticed that by inserting a slice of pig skin in between the necklace and the PADC, no great excess of alpha tracks were seen after 1 week of exposure in the freezer. There was, however, a clear signal through the pig skin from beta particles, confirming the potential of a uranium bead necklace posing a health risk.

  16. Lawson Wilkins: recollections by his daughter.

    PubMed

    McMaster, Elizabeth Wilkins

    2014-01-01

    Lawson Wilkins is well known as the "father" of the field of pediatric endocrinology, and his scientific accomplishments and legacy are thoroughly documented in this edition and elsewhere. Less well known, though, is what the man himself was like. Here, his daughter, Elizabeth McMaster, recalls the personal side of Dr. Wilkins including his upbringing as the son of a prominent Baltimore doctor, his medical education, establishment of a successful pediatric practice, and eventually the founding of the endocrine clinic at Johns Hopkins. Interwoven with anecdotes and reminiscences, this account provides a vivid sense of Wilkins' personality and life, from his boisterous nature and devotion to his family and career, to the tragic personal losses he endured. He was a man who threw himself fully into everything he did, whether it was making his own liqueur during Prohibition, collecting specimens from abnormally large circus performers as part of his earliest endocrine research, arranging raucous, impromptu singing parties, sailing the Chesapeake with friends, writing a definitive textbook of Pediatric Endocrinology, training a legion of fellows, or the pioneering work for which he is still known today. PMID:25024712

  17. Lawson Wilkins: recollections by his daughter

    PubMed Central

    2014-01-01

    Lawson Wilkins is well known as the “father” of the field of pediatric endocrinology, and his scientific accomplishments and legacy are thoroughly documented in this edition and elsewhere. Less well known, though, is what the man himself was like. Here, his daughter, Elizabeth McMaster, recalls the personal side of Dr. Wilkins including his upbringing as the son of a prominent Baltimore doctor, his medical education, establishment of a successful pediatric practice, and eventually the founding of the endocrine clinic at Johns Hopkins. Interwoven with anecdotes and reminiscences, this account provides a vivid sense of Wilkins’ personality and life, from his boisterous nature and devotion to his family and career, to the tragic personal losses he endured. He was a man who threw himself fully into everything he did, whether it was making his own liqueur during Prohibition, collecting specimens from abnormally large circus performers as part of his earliest endocrine research, arranging raucous, impromptu singing parties, sailing the Chesapeake with friends, writing a definitive textbook of Pediatric Endocrinology, training a legion of fellows, or the pioneering work for which he is still known today. PMID:25024712

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

    PubMed

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

    2016-04-01

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

  19. 'Radon Concentration Survey in Inner Rooms from Deputy Chamber and National Congress-Brasilia/DF'

    SciTech Connect

    Nicoli, Ieda Gomes; Cardozo, Katia Maria; Azevedo Gouvea, Vandir de

    2008-08-07

    Radon gas has been monitored in many environments such as rural and urban houses, high natural radioactivity areas and underground mining regions. Nevertheless few data are reported in literature about studies in state buildings. So we get in touch with these buildings managers, where work the Deputy Chamber and the National Congress in Brasilia--DF, in order to obtain radon data in these state buildings, so representative for brazilian people. In order to make a preliminary scanning of radon concentration in these buildings, it was put in selected points, radon nuclear track passive detectors type SSNTD, specifically polycarbonate Lexan, which were exposed for periods from two to five months. Afterwards they were sent to Nuclear Engineering Institute in Rio de Janeiro for analysis of {sup 222}Rn contents. Derived values, whose average value was about 73 Bq/m{sup 3}, were all under maximum permissible limits for radon 200 Bq/m{sup 3}, established by International Comission on Radiological Protection--ICRP 65, for inner environments of houses and state buildings. This work has been coordinated by CNEN Office in Braselia with effective participation of Nuclear Engineering Institute from CNEN--RJ, that has worked since beginning of april 2004, supplying and analysing radon detectors.

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

    SciTech Connect

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

    2015-10-01

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

  1. Radon and remedial action in Spokane River Valley residences: an interim report

    SciTech Connect

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

    1986-03-01

    Fifty-six percent of 46 residences monitored in the Spokane River Valley in eastern Washington/northern Idaho have indoor radon concentrations above the National Council for Radiation Protection (NCRP) guidelines of 8 pCi/1. Indoor levels were over 20 pCi/1 in eight homes, and ranged up to 132 pCi/1 in one house. Radon concentrations declined by factors of 4 to 38 during summer months. Measurements of soil emanation rates, domestic water supply concentrations, and building material flux rates indicate that diffusion of radon does not significantly contribute to the high concentrations observed. Rather, radon entry is dominated by pressure-driven bulk soil gas transport, aggravated by the local subsurface soil composition and structure. A variety of radon control strategies are being evaluated in 14 of these homes. Sub-surface ventilation by depressurization and overpressurization, basement overpressurization, and crawlspace ventilation are capable of successfully reducing radon levels below 5 pCi/1 in these homes. House ventilation is appropriate in buildings with low-moderate concentrations, while sealing of cracks has been relatively ineffective.

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

    PubMed

    Chauhan, Neetika; Chauhan, R P

    2015-06-01

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

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

    SciTech Connect

    York, E.L.

    1995-12-31

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

  4. Estimating the dynamics of groundwater input into the coastal zone via continuous radon-222 measurements.

    PubMed

    Burnett, William C; Dulaiova, Henrieta

    2003-01-01

    Submarine groundwater discharge (SGD) into the coastal zone has received increased attention in the last few years as it is now recognized that this process represents an important pathway for material transport. Assessing these material fluxes is difficult, as there is no simple means to gauge the water flux. To meet this challenge, we have explored the use of a continuous radon monitor to measure radon concentrations in coastal zone waters over time periods from hours to days. Changes in the radon inventories over time can be converted to fluxes after one makes allowances for tidal effects, losses to the atmosphere, and mixing with offshore waters. If one assumes that advective flow of radon-enriched groundwater (pore waters) represent the main input of 222Rn in the coastal zone, the calculated radon fluxes may be converted to water fluxes by dividing by the estimated or measured 222Rn pore water activity. We have also used short-lived radium isotopes (223Ra and 224Ra) to assess mixing between near-shore and offshore waters in the manner pioneered by. During an experiment in the coastal Gulf of Mexico, we showed that the mixing loss derived from the 223Ra gradient agreed very favorably to the estimated range based on the calculated radon fluxes. This allowed an independent constraint on the mixing loss of radon-an important parameter in the mass balance approach. Groundwater discharge was also estimated independently by the radium isotopic approach and was within a factor of two of that determined by the continuous radon measurements and an automated seepage meter deployed at the same site.

  5. A Study of Radon Background in the XENON100 Experiment

    SciTech Connect

    Weber, Marc

    2011-04-27

    The XENON100 Dark Matter experiment has recently published first results from an analysis of 11.2 live days of data, setting an upper limit on the spin-independent WIMP-nucleon elastic scattering cross section of 3.4x10{sup -44} cm{sup 2} at 55 GeV/c{sup 2} and 90% confidence level. This article focuses on one specific background component of the XENON100 detector by presenting two independent methods of measuring the {sup 222}Rn concentration during operation phase. A first estimate of radon activity is derived for the 11.2 days analysis, proving the feasibility of on-line radon monitoring. Remaining systematic uncertainties are discussed.

  6. Beta/alpha continuous air monitor

    DOEpatents

    Becker, G.K.; Martz, D.E.

    1988-06-27

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinquishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts. 7 figs.

  7. Beta/alpha continuous air monitor

    DOEpatents

    Becker, Gregory K.; Martz, Dowell E.

    1989-01-01

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinguishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts.

  8. Radon concentration measurements in bituminous coal mines.

    PubMed

    Fisne, Abdullah; Okten, Gündüz; Celebi, Nilgün

    2005-01-01

    Radon measurements were carried out in Kozlu, Karadon and Uzülmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m(-3). It is suggested that the ventilation rates should be rearranged to reduce the radon concentration.

  9. Indoor radon in New York State schools

    SciTech Connect

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

    1995-12-31

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

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

    PubMed

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

    2016-04-01

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

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

    PubMed

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

    2016-04-01

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

  12. Mother-daughter in vitro fertilization triplet surrogate pregnancy.

    PubMed

    Michelow, M C; Bernstein, J; Jacobson, M J; McLoughlin, J L; Rubenstein, D; Hacking, A I; Preddy, S; Van der Wat, I J

    1988-02-01

    A successful triplet pregnancy has been established in a surrogate gestational mother following the transfer of five embryos fertilized in vitro. The oocytes were donated by her biological daughter, and the sperm obtained from the daughter's husband. The daughter's infertility followed a total abdominal hysterectomy performed for a postpartum hemorrhage as a result of a placenta accreta. Synchronization of both their menstrual cycles was obtained using oral contraceptive suppression for 2 months, followed by stimulation of both the surrogate gestational mother and her daughter such that embryo transfer would occur at least 48 hr after the surrogate gestational mother's own ovulation. This case raises a number of medical, social, psychological, and ethical issues. PMID:3367072

  13. Involvement of oncogenes in radon-induced lung tumors in rats

    SciTech Connect

    Foreman, M.E.; McCoy, L.S.; Frazier, M.E.

    1992-12-31

    Several oncogenes, notably those of the ras and myc family, have been implicated in the induction of lung tumors. Although inhalation of radon and radon daughters has been shown to result in a high incidence of lung tumors, the role of oncogenes in these tumors (if any) remains unknown. In certain cases of chemically induced carcinogenesis, unique point mutations in the 12th, 59th, and 61st codons of H-ras and Ki-ras have been found to transform ras proto-oncogenes to dominant-acting oncogenes. We have isolated DNA from fixed, archived, radon-induced tumors in rats, amplified the oncogene of interest by polymerase chain reaction, and analyzed it by sequencing. Although we have not found any of the classically described point mutations in the H-ras gene, preliminary evidence indicates that several common mutations occur with high frequency in the second exon. These point mutations have not been seen in any {open_quotes}spontaneously{close_quotes} occurring tumors. At present we theorize that these mutations represent one of the secondary effects of a multi-step process in the development of these lung tumors. As this project expands, we are making a systematic effort to correlate the molecular data with the pathological data derived from the original studies of these archived tumors.

  14. Radon emanation chamber: High sensitivity measurements for the SuperNEMO experiment

    SciTech Connect

    Soulé, B.; Collaboration: SuperNEMO Collaboration; and others

    2013-08-08

    Radon is a well-known source of background in ββ0ν experiments due to the high Q{sub β} value of one of its daughter nucleus, {sup 214}Bi. The SuperNEMO collaboration requires a maximum radon contamination of 0.1 mBq/m{sup 3} inside its next-generation double beta decay detector. To reach such a low activity, a drastic screening process has been set for the selection of the detector's materials. In addition to a good radiopurity, a low emanation rate is required. To test this parameter, a Radon Emanation Setup is running at CENBG. It consists in a large emanation chamber connected to an electrostatic detector. By measuring large samples and having a low background level, this setup reaches a sensitivity of a few μ Bq. m{sup −2}. d{sup −1} and is able to qualify materials used in the construction of the SuperNEMO detector.

  15. Low Radioactive Techniques in SuperNEMO: Status of the Radon R and D

    SciTech Connect

    Perrot, F.

    2011-04-27

    Radon is a well-known source of background with respect to the search for neutrinoless double beta decay (0{nu}{beta}{beta}), due to the high Q{sub {beta}} value of one of its daughter nucleus {sup 214}Bi. Radon has been observed and reduced down to 6.5 mBq/m{sup 3} in the NEMO-3 experiment which is looking for the 0{nu}{beta}{beta} process in {sup 100}Mo and in six other isotopes. The SuperNEMO project, a next-generation double beta decay experiment which will also use a tracko-calorimeter technique, has been in an R and D phase since 2006. The goal is to reach a sensitivity of T{sub 1/2}(0{nu})>10{sup 26} y corresponding to an effective Majorana neutrino mass of 0.05-0.1 eV with 100 kg of {sup 82}Se. Such a sensitivity requires in particular to improve the radon radiopurity down to 0.1 mBq/m{sup 3} in the tracking chamber.

  16. 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.

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

    PubMed

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

    2015-10-01

    This article reports results of the first investigations on indoor radon, thoron and their decay products concentration in 25 primary schools of Banja Luka, capital city of Republic Srpska. The measurements have been carried out in the period from May 2011 to April 2012 using 3 types of commercially available nuclear track detectors, named: long-term radon monitor (GAMMA 1)- for radon concentration measurements (C(Rn)); radon-thoron discriminative monitor (RADUET) for thoron concentration measurements (C(Tn)); while equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) measured by Direct Radon Progeny Sensors/Direct Thoron Progeny Sensors (DRPS/DTPS) were exposed in the period November 2011 to April 2012. In each school the detectors were deployed at 10 cm distance from the wall. The obtained geometric mean concentrations were C(Rn) = 99 Bq m(-3) and C(Tn) = 51 Bq m(-3) for radon and thoron gases respectively. Those for equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) were 11.2 Bq m(-3) and 0.4 Bq m(-3), respectively. The correlation analyses showed weak relation only between C(Rn) and C(Tn) as well as between C(Tn) and EETC. The influence of the school geographical locations and factors linked to buildings characteristic in relation to measured concentrations were tested. The geographical location and floor level significantly influence C(Rn) while C(Tn) depend only from building materials (ANOVA, p ≤ 0.05). The obtained geometric mean values of the equilibrium factors were 0.123 for radon and 0.008 for thoron. PMID:26171822

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

    PubMed

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

    2015-10-01

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

  19. Radon Transport Into a Single-Family House with a Basement

    SciTech Connect

    Nazaroff, W.W.; Feustel, H.; Nero, A.V.; Revzan, K.L.; Grimsrud,D.T.; Essling, M.A.; Toohey, R.E.

    1984-01-01

    We describe the results of a five-month study during which {sup 222}Rn (radon) concentration, air-exchange (or ventilation) rate, and weather and radon source parameters were continuously monitored in a house near Chicago, with a view to accounting for the radon entry rate. The results suggest that the basement sump and perimeter drain-tile system played an important role in influencing the radon entry rate and that pressure-driven flow was more important than diffusion as a mechanism for radon entry. For the first 15 weeks of the study period the mean indoor radon concentration and air-exchange rate were 2.6 pCi {ell}{sup -1} (96 Bq m{sup -3}) and 0.22 hr{sup -1}, respectively; both parameters varied over a wide range. Radon concentration measured at the sump cover varied bimodally between 0-10 pCi {ell}{sup -1} (0-400 Bq m{sup -3}) and 300-700 pCi {ell}{sup -1} (10,000-30,000 Bq m{sup -3}). These two modes corresponded well to periods of low and high indoor radon concentration; average indoor concentrations for these periods were 1.5 and 6.5 pCi {ell}{sup -1} (55 and 240 Bq m{sup -3}), respectively. For data sorted into two groups according to radon activity at the sump, the indoor radon concentration showed little dependence on air-exchange rate. This result is accounted for by a model in which the radon entry rate, determined by mass balance, has two components--one diffusive, the other pressure-driven and presumed to be proportional to the air-exchange rate. In fitting this model to the data we found that (1) the flow component dominated the diffusive component for periods of both high and low activity at the sump; and (2) the magnitude of the diffusive component agreed well with the expected contributions of radon emanating from concrete and soil and diffusing into the house. To account for the flow component, we hypothesize that pressure drives air carrying a high concentration of radon generated in the soil, either through the bulk of the soil or along the

  20. Radon survey in Greece--risk assesment.

    PubMed

    Nikolopoulos, Dimitrios; Louizi, Anna; Koukouliou, Virginia; Serefoglou, Athina; Georgiou, Evangelos; Ntalles, Konstantinos; Proukakis, Charalambos

    2002-01-01

    A large scale radon survey using track etch detectors has been carried out from 1995 to 1998 in Greece in order to estimate the radon concentrations in Greek dwellings and the exposure of the Greek population to radon. The total data set consisted of 1,277 samples. Residential potential alpha energy concentration values ranged between (0.024 +/- 0.009) and (8 +/- 1) WLM per year (P < 0.05) and effective doses between (0.09 +/- 0.04) and (28 +/- 4) mSv (P < 0.05). The mean lifetime risk for the Greek population due to radon was found to be 0.4%.