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Sample records for airborne radon progeny

  1. 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.

  2. Field Investigation of the Surface-deposited Radon Progeny as a Possible Predictor of the Airborne Radon Progeny Dose Rate

    PubMed Central

    Sun, Kainan; Steck, Daniel J.; Field, R. William

    2009-01-01

    The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p < 0.0001) in nonsmoking environments. However, deposited 218Po was not significantly correlated to the above parameters in smoking environments. In multiple linear regression analysis, natural logarithm transformation was performed for airborne dose rate as the dependent variable, as well as for radon and deposited 218Po and 214Po as predictors. An interaction effect was found between deposited 214Po and an obstacle in front of the Retrospective Reconstruction Detector (RRD) in predicting dose rate (p = 0.049 and 0.058 for Pdose and Jdose, respectively) for nonsmoking environments. After adjusting for radon and deposited radon progeny effects, the presence of either cooking, usage of a fireplace, or usage of a ceiling fan significantly, or marginal significantly, reduced the Pdose to 0.65 (90% CI 0.42–0.996), 0.54 (90% CI 0.28–1.02) and 0.66 (90% CI 0.45–0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39–0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55–0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64–0.83) in the mean Pdose was noted, after adjusting for the radon and

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. Dosimetry of inhaled radon and thoron progeny

    SciTech Connect

    James, A.C.

    1994-06-01

    This chapter reviews recent developments in modeling doses received by lung tissues, with particular emphasis on application of ICRP`s new dosimetric model of the respiratory tract for extrapolating to other environments the established risks from exposure to radon progeny in underground mines. Factors discussed include: (1) the influence of physical characteristics of radon progeny aerosols on dose per unit exposure, e.g., the unattached fraction, and the activity-size distributions of clustered and attached progeny; (2) the dependence of dose on breathing rate, and on the exposed subject (man, woman or child); (3) the variability of dose per unit exposure in a home when exposure is expressed in terms of potential {alpha} energy or radon gas concentration; (4) the comparative dosimetry of thoron progeny; and (5) the effects of air-cleaning on lung dose. Also discussed is the apparent discrepancy between lung cancer risk estimates derived purely from dosimetry and the lung cancer incidence observed in the epidemiological studies of radon-exposed underground miners. Application of ICRP`s recommended risk factors appears to overestimate radon lung-cancer risk for miners by a factor of three. ``Normalization`` of the calculated effective dose is therefore needed, at least for {alpha} dose from radon and thoron progeny, in order to obtain a realistic estimate of lung cancer risk.

  11. 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.

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

    SciTech Connect

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

    1984-11-01

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

  13. 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

  14. Deposition of radon progeny in nonhuman primate nasal airways

    SciTech Connect

    Yeh, H.C.; Cheng, Y.S.; Su, Y.F. . Inhalation Toxicology Research Inst.); Morgan, K.T. )

    1991-01-01

    Information on aerosol deposition patterns in the human respiratory tract is needed to improve health risk estimates for exposure to airborne radon progeny. To investigate this, deposition of {sup 220}Rn progeny in Rhesus monkey nasal casts was examined. A substantial fraction of the inhaled ultrafine particles are deposited in the nasal cast. Deposition efficiency increases with decreasing particle size, reaching a maximum value of 80% for particles 1.7 nm in diameter. Breathing flow rate has a minimal effect on deposition efficiency. Deposition efficiencies for particles smaller than 100 nm in diameter are similar for monkey and human nasal casts. Equations based on turbulent diffusion can be fitted to these data for either inspirational or expirational flow. These mathematical expressions will be useful for modifying the inhaled particle deposition and dosimetry models. 20 refs., 9 figs., 1 tab (MHB)

  15. Radiometric Meteorology: radon progeny as tracers

    NASA Astrophysics Data System (ADS)

    Greenfield, Mark; Iwata, Atsushi; Ito, Nahoko; Kubo, Kenya; Komura, Kazu; Ishizaki, Miho

    2008-10-01

    In-situ measurement of atmospheric γ radiation from radon progeny determine rain and snow rates to better accuracy than standard rain gauges and gives a handle on how droplets are formed. The measured γ ray rates (GRR) have been shown to be proportional to a power of radiometric precipitation rates (RPR)^α, α giving a handle on the extent to which radon progeny are surface adsorbed or volume absorbed.ootnotetextM. B. Greenfield et al., J. Appl. Phys. 93, (2003) pp 5733-5741. More recently time dependent ratios of GRR from ^214Pb and ^214Bi, concentrated from collected rainwater, have been used to determine the elapsed time since activity from RPR, adhered to rain droplets, was removed from secular equilibrium. Ion exchange resins precipitate out the ^214Pb and ^214Bi ions, which are then filtered from 10s of liters of rainwater or snowmelt. A portable Ge detector is used to integrate the resulting activity over 5-10 min intervals. The measured evolution of these two activities from secular equilibrium to transient equilibrium has meteorological applications enabling both the determination of average elapsed times between the formation of raindrops and the time they reach the ground, as well as an estimate of the initial activity at the source of droplet formation.

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

    PubMed Central

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

    2013-01-01

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

  17. 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.

  18. 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.

  19. 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}.

  20. Radon progeny size distributions and enhanced deposition effects from high radon concentrations in an enclosed chamber.

    PubMed

    Leonard, Bobby E

    2004-01-01

    Prior work studying radon progeny in a small enclosed chamber found that at high (222)Rn concentrations an enhanced surface deposition was observed. Subsequent measurements for unfiltered air showed minimal charged particle mobility influence. Progeny particle size measurements reported here, performed at the US Department of Energy Environmental Measurement Laboratory (now with Home Security Department), using the EML graded screen array (GSA) system show in unfiltered air that the high (222)Rn levels causes a reduction in the attached (218)Po progeny airborne particulates and formation of additional normal sized unattached ( approximately 0.80 nm) and also even smaller (218)Po below 0.50 nm. At a (222)Rn level of 51 kBq m(-3), 73% of all (218)Po are of a mean particle diameter of about 0.40 +/- 0.02 nm. At this (222)Rn level, the ratio of (218)Po to (222)Rn airborne concentrations is reduced significantly from the concentration ratio at low (222)Rn levels. Similar reductions and size reformations were observed for the (214)Pb and (214)Bi/Po progeny. The particle size changes are further confirmed using the plateout rates and corresponding deposition velocities. The Crump and Seinfeld deposition theory provides the corresponding particle diffusion coefficients. With the diffusion coefficient to ultrafine clustered particle diameter correlation of Ramamurthi and Hopke, good agreement is obtained between EML GSA and deposition velocity data down to 0.40 nm. Strong evidence is presented that the progeny size reduction is due to, as a result of air ionization, the increased neutralization rate (primarily from electron scavenging of OH molecules) of the initially charged progeny. This is shown to increase with the (1/2) power of (222)Rn concentration and relative humidity as well as increased air change rate in the chamber. These results imply that at (222)Rn levels above 50 kBq m(-3), at relative humidity of 52%, a considerable reduction in lung dose could occur from

  1. Modeling surface backgrounds from radon progeny plate-out

    SciTech Connect

    Perumpilly, G.; Guiseppe, V. E.; Snyder, N.

    2013-08-08

    The next generation low-background detectors operating deep underground aim for unprecedented low levels of radioactive backgrounds. The surface deposition and subsequent implantation of radon progeny in detector materials will be a source of energetic background events. We investigate Monte Carlo and model-based simulations to understand the surface implantation profile of radon progeny. Depending on the material and region of interest of a rare event search, these partial energy depositions can be problematic. Motivated by the use of Ge crystals for the detection of neutrinoless double-beta decay, we wish to understand the detector response of surface backgrounds from radon progeny. We look at the simulation of surface decays using a validated implantation distribution based on nuclear recoils and a realistic surface texture. Results of the simulations and measured α spectra are presented.

  2. Microdosimetry of radon progeny: Application to risk assessment

    SciTech Connect

    Fisher, D.R.; Hui, T.E.; James, A.C. ); Bond, V.P. )

    1990-01-01

    We developed methods for calculating radiation doses to individual cells and cell nuclei of human bronchial epithelium from radon and progeny for specified levels of exposure, breathing rates, equilibrium factors, unattached fraction of progeny, and other factors that are important in radon dosimetry. If we also know which cells are likely precursors for cancer, and we also know their locations in the respiratory tract, we then may calculate the statistical probability that these cells are irradiated by alpha particles, the number of single alpha-particle hits, and the spectrum of doses delivered as a probability density in specific energy.

  3. Validity of the Kusnetz method for measuring radon progeny concentration

    SciTech Connect

    Duport, P.

    1998-12-31

    The standard Kusnetz and Rolle methods currently used to measure the concentration of potential alpha energy due to the presence of radon progeny were designed at a time when ventilation conditions were very different than in current mines. This report reviews those methods and evaluated whether they are still reliable when the residency time of air underground is very short compared to the half-life of short-lived radon progeny, and in particular, under the new ventilation conditions that exist in Saskatchewan uranium mines. The uncertainty in measurements of potential alpha energy concentration is evaluated using Monte Carlo simulation.

  4. 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.

  5. 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.

  6. Radon/radon progeny measurement proficiency program: Cumulative proficiency report (revised September 1987)

    SciTech Connect

    Not Available

    1987-09-01

    The program's immediate objective is to assist States and the public in selecting companies that have demonstrated competence in measuring indoor radon and radon progeny. This is achieved by evaluating, on a semiannual basis, the proficiency of companies' detector operations and the quality of their data management. The companies that demonstrate their proficiency are listed in the RMP proficiency reports. The program's long-term objectives are to promote standard measurement procedures among measurement companies and to establish quality assurance procedures for all measurement companies. The inclusion of a company in the report should not be interpreted as a certification or accreditation of that company. The report is only a source of measurement companies that have demonstrated capabilities for measuring radon and radon progeny levels.

  7. Radon: Chemical and physical states of radon progeny. Final technical report

    SciTech Connect

    Castleman, A.W. Jr.

    1996-12-31

    The evolving chemical and physical form of radon progeny influence their transport to the bioreceptor and the extent to which that receptor can take up these species into various tissues. When first born following radioactive decay processes, the potentially deleterious radon progeny undergo various physical and chemical transformations as they transcend from a highly charged to a neutral state, and interact with various constituents of the environment. These transformations impact on the extent to which the radon progeny become associated with aerosol particles on the one hand, and their ultimate chemical form that is available for uptake in the biosystem, on the other. The program, which originally commenced in 1987, dealt with the basic chemistry and physics of radon progeny and hence impacted on several themes of importance to the DOE/OHER radon program. One of these is dose response, which is governed by the physical forms of the radon progeny, their transport to the bioreceptor and the chemical forms that govern their uptake. The second theme had to do with cellular responses, one of the major issues motivating the work. It is well known that various sizes of ions and molecules are selectively transported across cell membrane to differing degrees. This ultimately has to do with their chemical and physical forms, charge and size. The overall objective of the work was threefold: (1) quantifying the mechanisms and rates of the chemical and physical transformation; (2) ascertaining the ultimate chemical forms, and (3) determining the potential interactions of these chemical species with biological functional groups to ascertain their ultimate transport and incorporation within cells.

  8. 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}.

  9. Radon and radon progeny outdoors in a valley of enhanced natural radioactivity

    NASA Astrophysics Data System (ADS)

    Pressyanov, Dobromir S.; Guelev, Methody G.; Sharkov, Borislav G.

    Results of a pilot study of 222Rn and 222Rn progeny outdoors and indoors in a valley of enhanced radioactivity, affected by uranium mining and milling have been summarized. Diurnal and spatial variations have been followed, and 222Rn concentrations in soil-gas have been determined. High outdoor concentrations of radon progeny during nights and at early mornings have been observed under the conditions of high air stagnation. The indoor concentrations were greater than the outdoor ones, however in most of the studied houses, the contribution of outdoor radon to the total exposure was found to be dominating. The cumulative exposure (for over 90% of the inhabitants) due to outdoor radon was estimated to be about 0.9 WLM per annum. These results reveal that lung-cancer risk excess by about 80% could be attributed to outdoor radon, provided that one assumes the risk coefficients (the cancer risk per unit of exposure) determined for occupational exposures. The study of different radon sources suggests that except for the uranium mining and milling, the generally enhanced natural radioactivity and meteorological conditions in this valley are of substantial importance. Valleys, such as the questioned one, may give an opportunity to check up the hypothesis about the existence of health effects at low doses of 222Rn progeny exposure.

  10. [Radon progeny as an experimental tool for dosimetry of nanoaerosols].

    PubMed

    Ruzer, L S; Apte, M G

    2009-01-01

    The study of aerosol exposure, dosimetry measurements and related quantitation of health effects are important to the understanding of the consequences of air pollution, and are discussed widely in the scientific literature. During the last 10 years the need to correlate aerosol exposure and biological effects has become especially important due to rapid development of a new, revolutionary industry of nanotechnology. Quantitative assessment of aerosol particle behavior in air and in lung deposition, and dosimetry in different parts of the lung, particularly for nanoaerosols, remains poor despite several decades of study. Direct measurements on humans are still needed in order to validate the hollow cast, animal studies, and lung deposition modeling. We discuss here the use of nanoscale radon decay products as an experimental tool in the study of local deposition and lung dosimetry for nanoaerosols. The issue of the safe use of radon progeny in such measurements is discussed based on a comparison of measured exposure in 3 settings: general population, miners, and in a human experiment conducted at the Paul Scherer Institute (PSI) in Switzerland. One of the properties of radon progeny is that they consist partly of 1 nm radioactive particles called unattached activity; having extremely small size and high diffusion coefficients, these particles can be potentially useful as radioactive tracers in the study of nanometer-sized aerosols. We present a theoretical and experimental study of the correlation between the unattached activity and aerosol particle surface area, together with a method for measurement of the unattached fraction.

  11. Recent developments in radon metrology: new aspects in the calibration of radon, thoron and progeny devices.

    PubMed

    Röttger, A; Honig, A

    2011-05-01

    Due to the importance of reliable measurements of radon activity concentration, one of the past developments in metrology was applied to the field of radon, thus meeting two basic needs: (1) the harmonisation of metrology within the scope of the mutual recognition arrangement, an arrangement drawn up by the International Committee of Weights and Measures for the mutual recognition of national standards and of calibrations issued by national metrology institutes and (2) the increased demands of the European Atomic Energy Community (EURATOM) directive, transferred into national radiation protection regulations with regard to natural radioactivity and its quality-assured measurements. This paper gives an overview of typical technical procedures in the radon-measuring technique group of PTB, covering all aspects of reference atmospheres (primary standards) for radon, thoron and their respective progenies.

  12. Temporal variation of radon progeny ratio in outdoor air.

    PubMed

    Kobayashi, Tsuneo

    2002-08-01

    This paper investigates the concentration ratio of radon progeny (218Po, 214Pb, and 214Bi) in outdoor air. From 1988 to 1998, alpha spectroscopy was used intermittently to collect progeny data outside the author's office located in the northeastern part of Japan. Let the quantity R(EEC) represent the ratio EEC(218Po)/[EEC(214Pb) + EEC(214Bi)], where, e.g., EEC(218Po) denotes the equilibrium equivalent radon concentration contributed by 218Po. The concentration ratio R(EEC) correlates with outdoor air stability. Statistical and time series analyses of R(EEC) indicate (1) outdoor air is more stable in the morning than in the afternoon, (2) outdoor air is more stable in summer/autumn than in winter/spring, and (3) in spite of no significant correlation between R(EEC) and wind speed, the power spectrum of R(EEC) appears similar to that of wind speed. This is probably due to the fact that near-surface mixing is not very sensitive to wind speed.

  13. RADON PROGENY AS AN EXPERIMENTAL TOOL FOR DOSIMETRY OF NANOAEROSOLS

    SciTech Connect

    Ruzer, Lev; Ruzer, Lev S.; Apte, Michael G.

    2008-02-25

    The study of aerosol exposure and dosimetry measurements and related quantitation of health effects are important to the understanding of the consequences of air pollution, and are discussed widely in the scientific literature. During the last 10 years the need to correlate aerosol exposure and biological effects has become especially important due to rapid development of a new, revolutionary industry ?-- nanotechnology. Nanoproduct commerce is predicted to top $1 trillion by 2015. Quantitative assessment of aerosol particle behavior in air and in lung deposition, and dosimetry in different parts of the lung, particularly for nanoaerosols, remains poor despite several decades of study. Direct measurements on humans are still needed in order to validate the hollow cast, animal studies, and lung deposition modeling. We discuss here the use of nanoscale radon decay products as an experimental tool in the study of local deposition and lung dosimetry for nanoaerosols. The issue of the safe use of radon progeny in such measurements is discussed based on a comparison of measured exposure in 3 settings: general population, miners, and in a human experiment conducted at the Paul Scherer Institute (PSI) in Switzerland. One of the properties of radon progeny is that they consist partly of 1 nm radioactive particles called unattached activity; having extremely small size and high diffusion coefficients, these particles can be potentially useful as radioactive tracers in the study of nanometer-sized aerosols. We present a theoretical and experimental study of the correlation between the unattached activity and aerosol particle surface area, together with a description of its calibration and method for measurement of the unattached fraction.

  14. Deposition of radon progeny in nonhuman primate nasal airways

    SciTech Connect

    Yeh, H.C.; Cheng, Y.S.; Morgan, K.T.

    1992-12-31

    Radon progeny are usually associated with ultrafine particles ranging in diameter from 0.001 to 0.005 {mu}m for {open_quotes}unattached{close_quotes} progeny and from 0.005 to 0.2 {mu}m for those attached to indoor aerosols. To assess the health effects of inhaling indoor radon progeny, it is necessary to study the regional deposition of these inhaled ultrafine particles. Laboratory animals are often used in studies of the toxicity of inhaled particles and vapors. Information on the deposition of particles larger than 0.2 {mu}m in the nasal passages of laboratory animals is available; however, there is little information on the deposition of particles smaller than 0.2 {mu}m. In this report, we describe the use of nasal casts of a rhesus monkey to measure total deposition of ultrafine aerosols, including unattached {sup 220}Rn progeny, in a unidirectional-flow inhalation exposure system. Deposition data were obtained for monodisperse silver aerosols with particle sizes ranging from 0.005 to 0.2 {mu}m, at several inspiratory and expiratory flow rates that represented normal breathing as well as hypo- and hyperventiliation. In addition, we studied the deposition of unattached {sup 22-}Rn progeny, at particle sizes from 0.001 to 0.003 {mu}m. The deposition efficiency decreased with increasing particle size, indicating that diffusion was the dominant deposition mechanism. The effect of flow rate was essentially negligible. Based on assumptions that turbulent flow and complete mixing of aerosols occur in the nasal airways, a general equation E = 1-exp (-a D{sup b}Q{sup c}) for d{sub p} {<=} 0.2 {mu}m, was derived, where E is the deposition efficiency, d{sub p} is the particle diameter, D is the diffusion coefficient, and Q is the flow rate. Constants a, b, and c are estimated from experimental data, for either inspiration or expiration. This mathematical expression will be useful for making modifications to both deposition and dosimetry models.

  15. Development of calibration facility for radon and its progenies at NIM (China).

    PubMed

    Liang, J C; Zheng, P H; Yang, Z J; Liu, H R; Zhang, M; Li, Z S; Zhang, L; Guo, Q J

    2015-11-01

    Accurate measurement of radon and its progenies is the basis to control the radon dose and reduce the risk of lung cancer caused. The precise calibration of measuring instrument is an important part of the quality control of measurements of the concentration of radon and radon progenies. To establish Chinese national standards and realise reliable calibrations of measuring instrument for radon and its progenies, a radon chamber with regulation capability of environmental parameters, aerosol and radon concentrations was designed and constructed at National Institute of Metrology (NIM). The chamber has a total volume of ∼20 m(3) including an exposure volume of 12.44 m(3). The radon concentration can be controlled from 12 Bq m(-3) to the maximum of 232 kBq m(-3). The regulation range of temperature, relative humidity and aerosol are 0.66 -44.39°C, 16.4 -95 %RH and 10(2) -10(6) cm(-3), respectively. The main advantages of the NIM radon chamber with respect to maintaining a stable concentration and equilibrium factor of radon progenies in a wide range through automatic regulation and control of radon and aerosol are described. PMID:25948838

  16. Development of calibration facility for radon and its progenies at NIM (China).

    PubMed

    Liang, J C; Zheng, P H; Yang, Z J; Liu, H R; Zhang, M; Li, Z S; Zhang, L; Guo, Q J

    2015-11-01

    Accurate measurement of radon and its progenies is the basis to control the radon dose and reduce the risk of lung cancer caused. The precise calibration of measuring instrument is an important part of the quality control of measurements of the concentration of radon and radon progenies. To establish Chinese national standards and realise reliable calibrations of measuring instrument for radon and its progenies, a radon chamber with regulation capability of environmental parameters, aerosol and radon concentrations was designed and constructed at National Institute of Metrology (NIM). The chamber has a total volume of ∼20 m(3) including an exposure volume of 12.44 m(3). The radon concentration can be controlled from 12 Bq m(-3) to the maximum of 232 kBq m(-3). The regulation range of temperature, relative humidity and aerosol are 0.66 -44.39°C, 16.4 -95 %RH and 10(2) -10(6) cm(-3), respectively. The main advantages of the NIM radon chamber with respect to maintaining a stable concentration and equilibrium factor of radon progenies in a wide range through automatic regulation and control of radon and aerosol are described.

  17. 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.

  18. Investigation of atmospheric, mechanical and other pressure effects influencing the levels of radon and radon progeny in buildings

    SciTech Connect

    Marley, F.

    1999-11-01

    Real-time data measurement and analysis have identified a number of influences affecting the variability and accumulation of radon and its progeny in indoor air. Observed cycles in radon concentrations were shown to be related to the influence of air-conditioning and water-heated central heating systems. The cyclical pattern, related to operation of the air-condition system, showed radon levels almost four times lower during the period when the system was switched On than when it was Off. When the heating system was switched On the radon and radon progeny levels were 40% lower than when it was switched Off. Under both regimes, it was possible to establish the over-riding influence of meteorological factors by separating the recurring cyclical component from the relevant data set. The general or trend level of indoor radon was determined substantially by the prevailing atmospheric conditions.

  19. 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.

  20. Control of respirable particles and radon progeny with portable air cleaners

    SciTech Connect

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

    1984-02-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles and radon progeny. Following injection of cigarette smoke and radon in a room-size chamber, decay rates for particles and radon progeny concentrations were measured with and without air cleaner operation. Particle concentrations were obtained for total number concentration and for number concentration by particle size. In tests with no air cleaner the natural decay rate for cigarette smoke was observed to be 0.2 hr/sup -1/. Air cleaning rates for particles were found to be negligible for several small panel-filters, a residential ion-generator, and a pair of mixing fans. The electrostatic precipitators and extended surface filters tested had significant particle removal rates, and a HEPA-type filter was the most efficient air cleaner. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in removing radon progeny. At low particle concentrations plateout of the unattached radon progeny is an important removal mechanism. Based on data from these tests, the plateout rate for unattached progeny was found to be 15 hr/sup -1/. The unattached fraction and the overall removal rate due to deposition of attached and unattached nuclides have been estimated for each radon decay product as a function of particle concentration. While air cleaning can be effective in reducing total radon progeny, concentrations of unattached radon progeny can increase with increasing air cleaning. 39 references, 26 figures, 9 tables.

  1. An historical overview of radon and its progeny: applications and health effects.

    PubMed

    Mc Laughlin, J

    2012-11-01

    Since its discovery by Dorn in 1900, studies of radon and its progeny have contributed to such diverse scientific fields as meteorology, geophysics, mineral exploration and radiation health effects. In addition to terrestrial scientific studies of radon, NASA missions in recent decades have yielded data on the behaviour of radon and its progeny on the Moon and on Mars. Radon has been used therapeutically for ∼100 y in the form of radon seeds for the irradiation of malignant tumours. It is, however, for its negative health effects that radon is better and more justifiably known. The causal role of radon and, in particular, its progeny in the elevated incidence of lung cancer in underground uranium miners was established in the 1950s. It is of historical interest to note that the fatal lung disease of silver miners in Saxony and Bohemia in the 16th century, was undoubtedly lung cancer caused by the high levels of radon in the mines. In recent decades there has been an ever-growing interest in the public health effects of exposure to radon in homes. Extensive radon epidemiological studies both of underground miners and of the general public in recent decades have quantified the lung cancer risks from radon exposure. Radon was classified in 1988 by International Agency for Research on Cancer as a human carcinogen and in 2009 the World Health Organization identified radon as the second cause of lung cancer globally after smoking. Radon control strategies are used by many governments to control and reduce the risk to public health from radon.

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

    SciTech Connect

    Scarpitta, S.C.; Tu, K.W.; Fisenne, I.M.; Cavallo, A.; Perry, P.

    1996-10-01

    Results are presented from the Fifth Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurements conducted in the EML radon exposure and test facility in May 1996. In total, thirty-four government, private and academic facilities participated in the exercise with over 170 passive and electronic devices exposed in the EML test chamber. During the first week of the exercise, passive and continuous measuring devices were exposed (usually in quadruplicate) to about 1,280 Bq m{sup {minus}3} {sup 222}Rn for 1--7 days. Radon progeny measurements were made during the second week of the exercise. The results indicate that all of the tested devices that measure radon gas performed well and fulfill their intended purpose. The grand mean (GM) ratio of the participants` reported values to the EML values, for all four radon device categories, was 0.99 {plus_minus} 0.08. Eighty-five percent of all the radon measuring devices that were exposed in the EML radon test chamber were within {plus_minus}1 standard deviation (SD) of the EML reference values. For the most part, radon progeny measurements were also quite good as compared to the EML values. The GM ratio for the 10 continuous PAEC instruments was 0.90 {plus_minus} 0.12 with 75% of the devices within 1 SD of the EML reference values. Most of the continuous and integrating electronic instruments used for measuring the PAEC underestimated the EML values by about 10--15% probably because the concentration of particles onto which the radon progeny were attached was low (1,200--3,800 particles cm{sup {minus}3}). The equilibrium factor at that particle concentration level was 0.10--0.22.

  3. Comparative study of various techniques for environmental radon, thoron and progeny measurements.

    PubMed

    Ramola, R C; Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Gusain, G S; Mishra, Rosaline; Sahoo, S K; Tokonami, S

    2015-11-01

    Long-term average concentrations of radon, thoron and progeny were measured in normal and high background radiation areas in India using different techniques. Radon, thoron and progeny concentrations were measured using Raduet, Pin-Hole dosimeter, deposition-based CR-39 and deposition-based direct radon/thoron progeny sensor (DRPS/DTPS) detector system. All these techniques were used at a same time inside an individual dwelling. Radon concentration was recorded higher than thoron concentration in Garhwal Homes (NBRA) while thoron concentration was found relatively higher in the houses of Chhatarpur area (HBRA) in Odisha, India. The values measured with the CR-39 detector-based technique were found comparable with the values measured with the LR-115 detector-based technique. The comparisons of results using various techniques and their usefulness in radiation measurements are discussed in detail.

  4. Radon and thoron progeny concentration variability in relation to meteorological conditions at Bucharest (Romania).

    PubMed

    Baciu, Adriana Celestina

    2005-01-01

    The paper presents results of natural radioactivity levels in the atmosphere obtained for a 5 years period (1994-1999) at the Bucharest Environmental Radioactivity Surveillance Station (BERSS). The variability of radon and thoron progeny activity concentrations is analysed in relation to the local dynamics of the meteorological parameters (wind speed, air temperature, air pressure, cloud cover, relative humidity). The radon and thoron progeny concentrations display a daily and seasonal variation, with the highest values in the early morning and the lowest values in the afternoon. The outdoor radon progeny concentrations show maximum values in autumn and minimum values in spring-summer. The outdoor thoron progeny concentrations display maximum values in autumn and minimum values in winter. Significant statistical correlations with the meteorological parameters were obtained. The study on the temporal variability of natural atmospheric radioactivity near Bucharest is a starting point for further assessment of the radiological consequences resulting from human activities.

  5. Intercomparison and intercalibration of passive/active radon and active radon progeny instruments and methods in North America

    SciTech Connect

    George, A.C.; Tu, Keng W.

    1993-06-01

    An intercomparison and intercalibration exercise for radon and radon progeny measurements made with active and passive instruments was held at EML from October 22--30,1992. Twenty-five participants submitted 96 passive integrating devices, eight active devices for radon, and seven integrating devices for potential alpha energy concentration (PAEC). In addition, 40 grab samples for radon progeny analysis were taken by five groups that participated in person during the intercomparison. The results reported to EML indicate that the majority of the participants (70%) obtained mean results within 10% of the EML reference value. Although the instruments used in this exercise are based on different principles of collection and detection, they all appear reliable. However, in some instances there seemed to be some minor problems with quality control and calibration bias. Also, the large counting errors for the PAEC experienced by some of the participants can be minimized by using higher sampling air flow rates without sacrificing instrument portability.

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

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

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

    PubMed

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

    2016-01-01

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

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

    PubMed Central

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

    2016-01-01

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

  9. Radon and radon progeny in 70 houses in the Tennessee Valley area: study design and measurement methods

    SciTech Connect

    Dudney, C.S.; Hawthorne, A.R.; Monar, K.P.; Quillen, J.L.; Clark, C. Jr.; Doane, R.W.; Wallace, R.G.; Reed, R.P.

    1986-01-01

    Levels of radon and its short-lived airborne progeny are being measured in a year-long study of 70 houses in four states in the Tennessee Valley. Various methods were used to solicit volunteers with differing degrees of success. Criteria for selection of houses in the study included presence of a lower level with cement floor and one or more block walls in contact with the soil, absence of obvious indications of technologically enhanced sources of radium, and proximity to one of four cities (Knoxville, Chattanooga, Birmingham, or Florence). By design, most houses in the study are in the same neighborhood as at least one other house in the study. Houses range in age from newly constructed to about 40 years old. Most of the houses have more than 2000 square feet of finished floor space. The lower level encompasses a garage in most cases. More complete information pertaining to house characteristics will be gathered in the course of the study. 19 refs., 1 fig.

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

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

    PubMed

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

    2006-01-01

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

  12. Dose-dependent in vivo cell-cycle changes following radon progeny exposure

    SciTech Connect

    Johnson, N.F.; Carpenter, T.R.; Hickman, A.W.; Jaramillo, R.J.; Gurule, D.M.

    1994-11-01

    Exposures to low concentrations of alpha-emitting radon progeny are reported by the U.S. Environmental Protection Agency to be the second leading cause of lung cancer. Current risk estimates for lung cancer from the inhalation of radon progeny are based on data from underground uranium miners. To produce such risk estimates, calculations are based on several assumptions concerning exposure-response relationships rather than dose-response relationships. A better understanding of the mechanisms of interactions between alpha particles, the cells of the respiratory tract, and the progression toward cancer may validate the mathematical models used to derive risk estimates.

  13. A survey of radon and thoron progeny for dwellings in Hong Kong.

    PubMed

    Yu, K N; Young, E C; Stokes, M J; Guan, Z J; Cho, K W

    1997-08-01

    The potential alpha energy concentrations of radon and thoron progeny have been surveyed for dwellings in Hong Kong and the mean values are obtained as 3.58 and 2.29 mWL, respectively. The relative importance of the value for thoron is unexpectedly high, which is attributed to the high 232Th content of the building materials used in Hong Kong. It has also been found that the potential alpha energy concentration values for radon progeny changed dramatically with the season due to the different aerosol contents in the air in different seasons. The factors affecting the potential alpha energy concentration values have also been studied. These factors fall into three categories, namely (1) the building characteristics including age of the buildings, wall coverings and floor coverings; (2) the location of sites including nearby environments and the elevation of the sites; and (3) the meteorological parameters including wind speed, atmospheric pressure, air temperature and relative humidity. For categories (1) and (2), all factors seem to affect the potential alpha energy concentration values, although the effects may be different for radon and thoron progeny, which may be due to the very much different half lives of radon and thoron gas and to the different behavior of radon and thoron progeny in the attachment to aerosols. For category (3), only wind speed has been found to have effects.

  14. 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.

  15. Design and performance of a recirculating radon-progeny aerosol generation and animal inhalation exposure system

    SciTech Connect

    Newton, G.J.; Cuddihy, R.G.; Yeh, H.C.; Boecker, B.B.

    1992-12-31

    At Inhalation Toxicology Research Institute we are conducting inhalation studies that expose laboratory animals to {sup 222}Rn progeny attached to vector aerosols typical of indoor and mine environments. These studies require exposures of up to 1500 working level months within a few hours. Thus, large amounts of {sup 226}Ra are needed to produce the gaseous {sup 222}Rn. A once-through exposure system was considered impractical because of statutory discharge limitations for radon and the large amounts of radium required. We therefore designed and constructed a recirculating exposure system that removes the aerosol after it has passed through the exposure chambers and recirculates the remaining purified radon. The purified radon and air mixture is then passed into a reaction aging chamber, where ingrowth of the progeny and their attachment to vector aerosols occur. The design includes (1) allowance for 45 mg {sup 226}Ra in the radon generator, (2) 40 L min{sup {minus}1} total flow rate, (3) CO{sub 2} removal, (4) reconstitution of oxygen tension and water vapor content to ambient levels, and (5) a trap for radon gas. Radon progeny exposure concentrations in the range of 5,000 to 100,000 working levels have been produced.

  16. 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.

  17. Model for assessing radiation dose to epithelial cells of the human respiratory tract from radon progeny

    SciTech Connect

    Fisher, D.R.; Hui, T.E.; James, A.C.

    1990-07-01

    A computational model was developed to evaluate radiation doses to sensitive cells from exposure to radon progeny throughout human bronchial epithelium. The model incorporated current information on nasal and oral filtration efficiencies for unattached radon progeny, characteristics of bronchial deposition by diffusive and inertial processes, mucous clearance and possible transfer of radon progeny to the airway epithelium, locations of target nuclei of secretory and basal cells in different regions of the bronchial tree epithelium, and other features. The model is useful for evaluating absorbed doses to various populations of target cell nuclei, the associated microdosimetric probability densities in specific energy, and the likelihood that target nuclei are hit one or more times by alpha-particle tracks. The model was applied to extrapolating lung cancer risks observed in underground miners to the general population exposed to low-level radon progeny in indoor home environments. The effect of increasing exposure rates by one and two orders of magnitude in both environments was modeled to determine the frequency of radiation events in target cell nuclei. The implications of dosimetric modeling for lung cancer risk analysis were also examined. 28 refs., 5 figs., 5 tabs.

  18. 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.

  19. Morphology of respiratory tract lesions in rats exposed to radon progeny

    SciTech Connect

    Dagle, G.E.; Cross, F.T.; Gies, R.A.

    1992-12-31

    We will discuss the morphologic features of lesions in the respiratory tract of rats exposed to radon and radon progeny. Groups of male Wister rats were exposed to from 10 to 1000 working levels (WL) of radon progeny in the presence of less than 1 to about 15 mg m{sup {minus}3} uranium ore dust. Cumulative exposures ranged from 20 to approximately 10,000 working level months (WLM). Higher exposure levels produced radiation pneumonitis characterized by interstitial fibrosis, associated with alveolar epithelial cell hyperplasia and accumulations of alveolar macrophages containing phagocytosed uranium ore dust. Nodular fibrosis and alveolar proteinosis were correlated with deposits of uranium ore dust. Vesicular emphysema also occurred at higher exposure levels. Pulmonary adenomatosis appeared to be a preneoplastic lesion; it was composed of nodular proliferation of bronchioloalveolar epithelium without disruption of the general architecture of the parenchyma. At exposure levels where rats lived longer than 1 y, lung tumors and a few tumors of the nasal cavity developed. The principal lung tumors were pulmonary adenomas, bronchioloalveolar carcinomas, papillary adenocarcinomas, epidermoid carcinomas, and adenosquamous carcinomas. Occasionally, malignant mesotheliomas and sarcomas were also present. The malignant lung tumors were characterized by invasion and occasionally metastasized to regional lymph nodes. Lower exposure rates produced more tumors, generally of different histologic types, and more fatal tumors than higher exposure rates. The similarity to relationships of human radon progeny exposure as far as incidence and types of lung tumors establish the validity of this animal model for studying radon carcinogenesis in humans.

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

    PubMed

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

    2015-11-01

    The equilibrium factor F between radon and its short-lived progenies is an important parameter to estimate radon exposure of humans. Therefore, indoor and outdoor concentrations of radon and its short-lived radon progeny were measured in Beijing area using a continuously measuring device, in an effort to obtain information on the F value. The results showed that the mean values of F were 0.58 ± 0.13 (0.25-0.95, n = 305) and 0.52 ± 0.12 (0.31-0.91, n = 64) for indoor and outdoor, respectively. The indoor F value during haze-fog days was higher than the typical value of 0.4 recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation, and it was also higher than the values of 0.47 and 0.49 reported in the literature. A positive correlation was observed between indoor F values and PM2.5 concentrations (R (2) = 0.71). Since 2013, owing to frequent heavy haze-fog events in Beijing and surrounding areas, the number of the days with severe pollution remains at a high level. Future studies on the impact of the ambient fine particulate matter on indoor radon progeny equilibrium factor F could be important. PMID:26143065

  1. 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.

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

    PubMed

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

    2015-11-01

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

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

    PubMed

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

    2015-11-01

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

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

    PubMed

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

    2015-11-01

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

  5. Multi-parametric approach towards the assessment of radon and thoron progeny exposures

    SciTech Connect

    Mishra, Rosaline E-mail: rosaline.mishra@gmail.com; Sapra, B. K.; Mayya, Y. S.

    2014-02-15

    Conventionally, the dosimetry is carried out using radon and thoron gas concentration measurements and doses have been assigned using assumed equilibrium factors for the progeny species, which is inadequate pertaining to the variations in equilibrium factors and possibly due to significant thoron. In fact, since the true exposures depend upon the intricate mechanisms of progeny deposition in the lung, therefore an integrated approach for the assessment of progeny is essential. In this context, the recently developed deposition based progeny concentration measurement techniques (DTPS: Direct Thoron progeny sensors and DRPS: Direct Radon progeny sensors) appear to be best suited for radiological risk assessments both among occupational workers and general study populations. DTPS and DRPS consist of aluminized mylar mounted LR115 type passive detectors, which essentially detects the alpha particles emitted from the deposited progeny atoms on the detector surface. It gives direct measure of progeny activity concentrations in air. DTPS has a lower limit of detection limit of 0.1 Bq/m{sup 3} whereas that for DRPS is 1 Bq/m{sup 3}, hence are perfectly suitable for indoor environments. These DTPS and DRPS can be capped with 200-mesh type wire-screen to measure the coarse fraction of the progeny concentration and the corresponding coarse fraction deposition velocities as well as the time integrated fine fraction. DTPS and DRPS can also be lodged in an integrated sampler wherein the wire-mesh and filter-paper are arranged in an array in flow-mode, to measure the fine and coarse fraction concentration separately and simultaneously. The details are further discussed in the paper.

  6. Multi-parametric approach towards the assessment of radon and thoron progeny exposures

    NASA Astrophysics Data System (ADS)

    Mishra, Rosaline; Sapra, B. K.; Mayya, Y. S.

    2014-02-01

    Conventionally, the dosimetry is carried out using radon and thoron gas concentration measurements and doses have been assigned using assumed equilibrium factors for the progeny species, which is inadequate pertaining to the variations in equilibrium factors and possibly due to significant thoron. In fact, since the true exposures depend upon the intricate mechanisms of progeny deposition in the lung, therefore an integrated approach for the assessment of progeny is essential. In this context, the recently developed deposition based progeny concentration measurement techniques (DTPS: Direct Thoron progeny sensors and DRPS: Direct Radon progeny sensors) appear to be best suited for radiological risk assessments both among occupational workers and general study populations. DTPS and DRPS consist of aluminized mylar mounted LR115 type passive detectors, which essentially detects the alpha particles emitted from the deposited progeny atoms on the detector surface. It gives direct measure of progeny activity concentrations in air. DTPS has a lower limit of detection limit of 0.1 Bq/m3 whereas that for DRPS is 1 Bq/m3, hence are perfectly suitable for indoor environments. These DTPS and DRPS can be capped with 200-mesh type wire-screen to measure the coarse fraction of the progeny concentration and the corresponding coarse fraction deposition velocities as well as the time integrated fine fraction. DTPS and DRPS can also be lodged in an integrated sampler wherein the wire-mesh and filter-paper are arranged in an array in flow-mode, to measure the fine and coarse fraction concentration separately and simultaneously. The details are further discussed in the paper.

  7. Alternative assessment of exposure of uranium miners to radon and progeny using {sup 210}Pb in vivo measurements

    SciTech Connect

    Guilmette, R.A.; Snipes, M.B.; Hoover, M.D.

    1997-12-01

    Significant uncertainties exist in estimating uranium miners` exposure to radon and its radioactive progeny during their mining careers. These uncertainties are due in part to the limited number and poor quality of measurements of radon and radon progeny concentrations made in various uranium mines, particularly during the 1945 to 1960 time period during which radon levels were the highest because of ineffective ventilation in the mines. We hypothesize that a major contributor to the 30-fold variability noted in lung cancer risk factors for the 12 epidemiological studies done on uranium miners worldwide is due to exposure estimate bias among the different populations.

  8. Optimization of the Timepix chip to measurement of radon, thoron and their progenies.

    PubMed

    Janik, Miroslaw; Ploc, Ondrej; Fiederle, Michael; Procz, Simon; Kavasi, Norbert

    2016-01-01

    Radon and thoron as well as their short-lived progenies are decay products of the radium and thorium series decays. They are the most important radionuclide elements with respect to public exposure. To utilize the semiconductor pixel radiation Timepix chip for the measurement of active and real-time alpha particles from radon, thoron and their progenies, it is necessary to check the registration and visualization of the chip. An energy check for radon, thoron and their progenies, as well as for (241)Am and(210)Po sources, was performed using the radon and thoron chambers at NIRS (National Institute of Radiological Sciences). The check found an energy resolution of 200 keV with a 14% efficiency as well as a linear dependency between the channel number (cluster volume) and the energy. The coefficient of determination r(2) of 0.99 for the range of 5 to 9 MeV was calculated. In addition, an offset for specific Timepix configurations between pre-calibration for low energy from 6 to 60 keV, and the actual calibration for alpha particles with energies from 4000 to 9000 keV, was detected. PMID:26547560

  9. Analysis of radon and thoron progeny measurements based on air filtration.

    PubMed

    Stajic, J M; Nikezic, D

    2015-02-01

    Measuring of radon and thoron progeny concentrations in air, based on air filtration, was analysed in order to assess the reliability of the method. Changes of radon and thoron progeny activities on the filter during and after air sampling were investigated. Simulation experiments were performed involving realistic measuring parameters. The sensitivity of results (radon and thoron concentrations in air) to the variations of alpha counting in three and five intervals was studied. The concentration of (218)Po showed up to be the most sensitive to these changes, as was expected because of its short half-life. The well-known method for measuring of progeny concentrations based on air filtration is rather unreliable and obtaining unrealistic or incorrect results appears to be quite possible. A simple method for quick estimation of radon potential alpha energy concentration (PAEC), based on measurements of alpha activity in a saturation regime, was proposed. Thoron PAEC can be determined from the saturation activity on the filter, through beta or alpha measurements.

  10. RADON AND PROGENY SOURCED DOSE ASSESSMENT OF SPA EMPLOYEES IN BALNEOLOGICAL SITES.

    PubMed

    Uzun, Sefa Kemal; Demiröz, Işık

    2016-09-01

    This study was conducted in the scope of IAEA project with the name 'Establishing a Systematic Radioactivity Survey and Total Effective Dose Assessment in Natural Balneological Sites' (TUR/9/018), at the Health Physics department of Sarayköy Nuclear Research and Training Center (SANAEM). The aim of this study is estimation of radon and progeny sourced effective dose for the people who are working at the spa facilities by measuring radon activity concentration (RAC) at the ambient air of indoor spa pools and dressing rooms. As it is known, the source of the radon gas is the radium content of the earth crust. Therefore, thermal waters coming from ground may contain dissolved radon and the radon can diffuse water to air. So the ambient air of spa pools can contain serious RAC that depends on a lot of parameters. In this regard, RAC measurements were executed at the 70 spa facilities in Turkey. The measurements were done with both active and passive methods at ambient air of spa pools and dressing rooms. Thus, active measurements were carried out by using the Alphaguard(®) with diffusion mode during half an hour, and passive measurements were carried out by using the humidity resistive CR-39 radon detectors during 2 months. Results show that RAC values at ambient air of spa pools varies between 13 Bq m(-3) and 10 kBq m(-3) Because long-term measurements are more reliable, if it is available, for dose calculations passive radon measurements (with CR-39 detectors) at ambient air of spa pools and dressing rooms were used, otherwise active measurement results were used. With the measurement by the conversion coefficients of ICRP 65 and occupational data of the employees has got from questionary forms, effective dose values were calculated. According to the calculations, spa employees are exposed to annual average dose between 0.05 and 29 mSv because of radon and progeny.

  11. RADON AND PROGENY SOURCED DOSE ASSESSMENT OF SPA EMPLOYEES IN BALNEOLOGICAL SITES.

    PubMed

    Uzun, Sefa Kemal; Demiröz, Işık

    2016-09-01

    This study was conducted in the scope of IAEA project with the name 'Establishing a Systematic Radioactivity Survey and Total Effective Dose Assessment in Natural Balneological Sites' (TUR/9/018), at the Health Physics department of Sarayköy Nuclear Research and Training Center (SANAEM). The aim of this study is estimation of radon and progeny sourced effective dose for the people who are working at the spa facilities by measuring radon activity concentration (RAC) at the ambient air of indoor spa pools and dressing rooms. As it is known, the source of the radon gas is the radium content of the earth crust. Therefore, thermal waters coming from ground may contain dissolved radon and the radon can diffuse water to air. So the ambient air of spa pools can contain serious RAC that depends on a lot of parameters. In this regard, RAC measurements were executed at the 70 spa facilities in Turkey. The measurements were done with both active and passive methods at ambient air of spa pools and dressing rooms. Thus, active measurements were carried out by using the Alphaguard(®) with diffusion mode during half an hour, and passive measurements were carried out by using the humidity resistive CR-39 radon detectors during 2 months. Results show that RAC values at ambient air of spa pools varies between 13 Bq m(-3) and 10 kBq m(-3) Because long-term measurements are more reliable, if it is available, for dose calculations passive radon measurements (with CR-39 detectors) at ambient air of spa pools and dressing rooms were used, otherwise active measurement results were used. With the measurement by the conversion coefficients of ICRP 65 and occupational data of the employees has got from questionary forms, effective dose values were calculated. According to the calculations, spa employees are exposed to annual average dose between 0.05 and 29 mSv because of radon and progeny. PMID:26424134

  12. Micronuclei induced by radon and its progeny in deep-lung fibroblasts of rats in vivo and in vitro

    SciTech Connect

    Khan, M.A.; Cross, F.T.; Jostes, R.; Hui, E.; Morris, J.E.; Brooks, A.L.

    1994-07-01

    Genotoxic damage induced by radon and its progeny was investigated using the micronucleus assay in deep-lung fibroblasts to compare the response induced in vitro with that induced from inhalation of radon and its progeny in vivo. Male Wistar rats were exposed to 0, 115, 213, and 323 working-level months (WLM) of radon and it progeny by inhalation. After sacrifice, the cells were isolated and grown in culture, and the frequency of micronuclei was determined. A linear increase in the frequency of micronuclei was measured as a function of exposure [micronuclei/1000 binucleated cells = (29 {+-} 9) + (0.47 {+-} 0.04) WLM]. To compare exposure in WLM to dose in mGy, and to study how cell proliferation influences the way inhalation of radon and its progeny induces micronuclei, lung fibroblasts were isolated and exposed in vitro to graded doses from radon and its progeny after either 16 or 96 h in tissue culture. Cell cycle stage at the time of exposure was determined using flow cytometry. Primary lung fibroblasts exposed as either nondividing or dividing cells showed dose-dependent increases in micronuclei [micronuclei/1000 binucleated cells = (33 {+-} 40) + (593 {+-} 68)D and micronuclei/1000 binucleated cells = (27 {+-} 69) + (757 {+-} 88)D, respectively, where D is dose in Gy]. Results showed no significant influence (P = 0.20) of cell proliferation at the time of exposure on the frequency of micronuclei induced by radon and its progeny. Comparing dose-response relationships for nondividing cells to the exposure response for cells exposed by inhalation of radon and its progeny, it was estimated that a 1-WLM exposure in vivo caused the same amount of cytogenetic damage as produced by 0.79 mGy in vitro. In vivo/in vitro research using the micronucleus assay in lung fibroblasts serves as a powerful tool to estimate effective dos to cells in the respiratory tract after inhalation of radon and its progeny. 34 refs., 3 figs., 2 tabs.

  13. The portable device for continual measurement of radon progenies on filter using the detector Timepix.

    PubMed

    Bulanek, Boris; Hulka, Jiri; Jilek, Karel; Stekl, Ivan

    2015-06-01

    In this article, a portable device was presented for continual measuring of equilibrium equivalent concentration (EEC) of (222)Rn based on the Timepix detector with 300-µm-thick active layer. In order to have a portable device, a filtration head was developed for collecting short-lived radon progenies attached on aerosols. The short-lived progenies are estimated from analysing alphas from decay of (218,214)Po from Millipore filter after termination of filtration. Comparison with beta measurement was done as well. The dependence of EEC on an air flow and filtration time was studied. The low-level detection limit for EEC was estimated from the last 10 min of 3-h decay measurement and was found in the range of 40-70 Bq m(-3). EEC was measured in National Radiation Protection Institute radon chamber, and results were compared with the commercial detector Fritra4. PMID:25990115

  14. Measurement of short-lived radon progenies by simultaneous αγ-spectrometry at the German radon reference chamber

    NASA Astrophysics Data System (ADS)

    Paul, A.; Röttger, S.; Honig, A.; Sulima, T.; Buchholz, A.; Keyser, Uwe

    1999-02-01

    In the German radon reference chamber, the short-lived radon progenies are separated by a sample tube according to the attached or unattached fraction, while their activity concentration is afterwards measured by simultaneous α- and γ-spectrometry. The results are expressed by the equilibrium factor F and the unattached fraction fp (International Commission on Radiological Protection, ICRP Publication 50, Ann. ICRP 17 (1987) 1). Both F and fp, can be therefore studied with respect to the full set of environmental parameters, e.g. temperature, humidity, air pressure and aerosol concentration (Honig et al., Nucl. Instr. and Meth. A 416 (1998) 525). Up to now, well-defined and stable equilibrium factors in the interval from 0.1 to 1.0 have been established. In correlation with this, the unattached fraction can be varied from 0.01 to 0.9. The sample and measuring technique for the short-lived radon progenies described in this work is the basis for fundamental studies with regard to the equilibrium factor and the unattached fraction as well as for application as a calibration facility.

  15. Effects of acute radon progeny exposure on rat alveolar macrophage number and function

    SciTech Connect

    Johnson, N.F.; Newton, G.J.; Guilmette, R.A.

    1992-12-31

    Alveolar macrophages play a key role in removal and translocation of inhaled particles and have been shown to influence proliferation of Alveolar Type II cells and fibroblasts. The effect of radon progeny on alveolar macrophage number and function is not documented. Functional impairment of alveolar macrophages may be an ancillary event in the induction of pulmonary lesions and may also indicate dose to the peripheral lung. In our study, rats were exposed to 1000 working level months (WLM) of radon progeny over a 3- to 5-h period, with a vector aerosol of environmental tobacco smoke. Groups of animals were sacrificed, and the lungs were lavaged immediately after exposure and on days 2, 18, 16, 21 and 29 after exposure. The numbers and viabilities of the lavaged macrophages were determined. Cytological preparations were made to determine the number of binucleated/multinucleated macrophages and macrophages containing micronuclei. The DNA content was measured flow-cytometrically using Hoechst 33342, and phagocytosis was assayed by determining the uptake of fluorescent microspheres. The numbers and viabilities of macrophages recovered from exposed animals were similar to the values measured for control animals. There was no evidence of an inflammatory reaction during any period after radon progeny exposure. Nuclear atypia, evidenced by increases in the number of binucleated cells and cells with micronuclei, occurred in animals 8 days after exposure, and this response peaked at 21 days after exposure. The phagocytic capability of the alveolar macrophages was not significantly affected at any time point after exposure. These results show that there was little functional impairment of alveolar macrophages in rats after acute radon-progeny exposure; however, there was long-standing interference with cell division, resulting in binucleated and micronucleated macrophages.

  16. 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.

  17. 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.

  18. Radon measurements aboard the Kuiper Airborne Observatory

    NASA Technical Reports Server (NTRS)

    Kritz, Mark A.; Rosner, Stefan W.

    1995-01-01

    We have carried out three (piggyback) radon-related projects aboard the KAO. The first, which was limited to upper tropospheric measurements while in level flight, revealed the systematic occurrence of unexpectedly high radon concentrations in this region of the atmosphere. The second project was an instrument development project, which led to the installation of an automatic radon measurement system aboard the NASA ER-2 High Altitude Research Aircraft. In the third, we installed a new system capable of collecting samples during the normal climb and descent of the KAO. The results obtained in these projects have resulted in significant contributions to our knowledge of atmospheric transport processes, and are currently playing a key role in the validation of global circulation and transport models.

  19. A review of lung-to-blood absorption rates for radon progeny.

    PubMed

    Marsh, J W; Bailey, M R

    2013-12-01

    The International Commission on Radiological Protection (ICRP) Publication 66 Human Respiratory Tract Model (HRTM) treats clearance of materials from the respiratory tract as a competitive process between absorption into blood and particle transport to the alimentary tract and lymphatics. The ICRP recommended default absorption rates for lead and polonium (Type M) in ICRP Publication 71 but stated that the values were not appropriate for short-lived radon progeny. This paper reviews and evaluates published data from volunteer and laboratory animal experiments to estimate the HRTM absorption parameter values for short-lived radon progeny. Animal studies showed that lead ions have two phases of absorption: ∼10 % absorbed with a half-time of ∼15 min, the rest with a half-time of ∼10 h. The studies also indicated that some of the lead ions were bound to respiratory tract components. Bound fractions, f(b), for lead were estimated from volunteer and animal studies and ranged from 0.2 to 0.8. Based on the evaluations of published data, the following HRTM absorption parameter values were derived for lead as a decay product of radon: f(r) = 0.1, s(r) = 100 d(-1), s(s) = 1.7 d(-1), f(b) = 0.5 and s(b) = 1.7 d(-1). Effective doses calculated assuming these absorption parameter values instead of a single absorption half-time of 10 h with no binding (as has generally been assumed) are only a few per cent higher. However, as there is some conflicting evidence on the absorption kinetics for radon progeny, dose calculations have been carried out for different sets of absorption parameter values derived from different studies. The results of these calculations are discussed.

  20. 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.

  1. An optimized system for measurement of radon levels in buildings by spectroscopic measurement of radon progeny

    NASA Astrophysics Data System (ADS)

    Fröjdh, A.; Thungström, G.; Fröjdh, C.; Petersson, S.

    2011-12-01

    Radon gas, 222Rn, is a problem in many buildings. The radon gas is not harmful in itself, but the decay chain contains charged elements such as 218Po, and 214Po ions which have a tendency to stick to the lungs when inhaled. Alpha particles from the decay of these ions cause damages to the lungs and increase the risk of lung cancer. The recent reduction in the limits for radon levels in buildings call for new simple and efficient measurement tools [1]. The system has been optimized through modifications of the detector size, changes to the filters and the design of the chamber. These changes increase the electric field in the chamber and the detection efficiency.

  2. Exposure to radon progeny, tobacco use and lung cancer in a case-control study in Southern China

    SciTech Connect

    Shu Xiang Yao; Fu Ming Zhang; Lubin, J.H.; Boice, J.D. Jr.; Blot, W.J.; You Lin Qiao; Jun Yao Li; Shu Kan Cai

    1994-06-01

    A case-control study of lung cancer in underground tin miners in southern China was conducted to examine the interplay between exposure to radon progeny and tobacco use. A total of 460 incident cases and 1,043 controls were evaluated. Among the exposed, mean radon progeny exposures were 600 and 427 working level months (WLM) for cases and controls, respectively. The excess relative risk per WLM (ERR/WLM) was 0.28% overall, with a 95% confidence interval of 0.1-0.6%, similar to the estimate from a cohort study in a related population of underground miners. The established patterns of lung cancer associated with radon were seen; the ERR/WLM decreased with attained age and time since last exposure. Conditional on total exposure, risk was highest for exposures delivered at a low rate. The ERR/WLM did not differ significantly among current and former smokers or within categories of time since last exposure. The relative risk relationship between exposure to radon progeny and tobacco use was consistent with a multiplicative model, but the best-fitting model was intermediate between additive and multiplicative; an additive association was rejected. Adjustment for exposure to inorganic arsenic, a known lung carcinogen, reduced the estimate of the ERR/WLM from 0.86% to 0.28%. The ERR/WLM estimate was homogeneous across subgroups defined by workers not exposed to arsenic and quartiles of cumulative arsenic exposure. Although squamous cell carcinoma was the predominant cell type, small cell and adenocarcinoma histologies appeared more strongly associated with exposure to radon progeny. The finding of a stronger trend with exposure with small cell carcinomas and adenocarcinomas, compared to squamous cell carcinomas, occurred primarily at younger ages at diagnosis. Finally, the risk of lung cancer was higher if exposure to radon progeny and tobacco use occurred together than if the exposure to radon progeny entirely preceded tobacco use. 24 refs., 3 figs., 8 tabs.

  3. Determination of rain age via {gamma} rays from accreted radon progeny

    SciTech Connect

    Greenfield, M. B.; Ito, N.; Iwata, A.; Kubo, K.; Ishigaki, M.; Komura, K.

    2008-10-01

    The relative {gamma} ray activities from {sup 214}Pb and {sup 214}Bi condensed from precipitation are used to determine its 'age', the average time the accreted activity has been removed from secular equilibrium. A verifiable assumption that radon progeny on/in the surface/volume of droplets mostly remains in secular equilibrium until they begin their descent, enables estimates of their transit times to ground of typically a few tens of minutes. This agrees well with the time expected for the activity on the surface of droplets to reach the ground from heights of a few kilometers. The half lives of {gamma} activities from {sup 214}Bi and {sup 214}Pb, 19.7 and 26.9 min, respectively, are on the same scale as transit time to ground and close enough to each other to measure ratios of activities from secular equilibrium (1.00) to transient equilibrium (3.88) within a few hundreds of minutes. The ratio of {gamma} count rates is independent of knowledge of either initial activity or any systematic errors and thus limited only by the uncertainty from counting statistics, which from condensates of 5-30 l of rain viewed with 2{pi} solid angle by a 50% efficient, high-resolution Ge detector is only a few percent. These ratios fit extremely well to known theoretical curves, which cannot only be used to date rain but can also be extrapolated backward to determine radon progeny activities in rain prior to its descent, knowledge of which may facilitate further studies using radon progeny as tracers.

  4. 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

  5. A two-particle-size model and measurements of radon progeny near the Earth`s surface

    SciTech Connect

    Schery, S.D.; Wasiolek, P.T.

    1993-12-20

    Measurements of radon progeny in the attached-to-aerosol and unattached-to-aerosol states were made in central New Mexico. Simultaneous measurements of attached and unattached progeny at 0.2 and 2 m were carried out over a range of meteorological and terrain conditions. The ratio of the average progeny concentrations at 2.2 to 0.2 m was 1.06 for total progeny and 1.35 for unattached progeny, indicating a net downward flux, with the unattached progeny dominating removal to the Earth`s surface. Progeny/parent activity ratios greater than 1 were clearly detected (for example, at 0.2 m, the average {sup 214}Pb/{sup 218}Po ratio was 1.43 {+-} 0.10), providing partial support for some previous observations. A two-particle-size model for radon progeny is able to account for the observed gradients, progeny/parent activity ratios greater than 1, and some trends in the experimental measurements as a function of meteorological conditions. 32 refs., 7 figs., 4 tabs.

  6. Concurrent induction of micronuclei and gene mutations in rat lung fibroblasts in vivo following inhalation of radon and radon progeny

    SciTech Connect

    Khan, M.A.; Jostes, R.F.; Cross, F.T.; Brooks, A.L.

    1994-12-31

    Inhaled radon induces genotoxicity and cancer in lung cells. To determine the amount and type of genotoxic damage induced in the lung, male Wistar rates were exposed to 323 working level months (WLM) of radon and radon progeny. Primarily lung fibroblasts obtained 4 h after the end of the exposure were analyzed for (1) chromosomal damage using the micronucleus/cytochalasin B technique and (2) gene mutation using a thioguanine selection procedure. The frequency of micronuclei was determined by scoring 2000 binucleated cells for each of 2 individuals in control and 5 individuals in exposed groups. The mean frequency of micronuclei was 31/1000 binucleated cells in controls and 187/1000 binucleated cells in exposed group of animals. The frequency of gene mutations was determined by plating 10{sup 5} cells in each of 45 dishes (4.5 x 10{sup 6} cells) from controls and 40 dishes (4.0 x 10{sup 6} cells) from exposed animals, in a mixture of culture medium and 6-thioguanine. The number of mutant cell colonies was recorded after 14 days. The control and the exposed cell populations showed 4 and 34 surviving cells was 5 for controls and 83 for the exposed cell population. Thus there was a 6-fold increase in the frequency of micronuclei and an 18-fold increase in the frequency of gene mutations relative to controls. The results demonstrate that 2 major endpoints being implicated in carcinogenesis namely, gene mutations and chromosomal aberrations induced by inhaled radon can be detected and quantified concurrently in mammalian lung cells in vivo.

  7. Quantitative Interpretation of Air Radon Progeny Fluctuations in Terms of Stability Conditions in the Atmospheric Boundary Layer

    NASA Astrophysics Data System (ADS)

    Salzano, Roberto; Pasini, Antonello; Casasanta, Giampietro; Cacciani, Marco; Perrino, Cinzia

    2016-09-01

    Determining the mixing height using a tracer can improve the information obtained using traditional techniques. Here we provide an improved box model based on radon progeny measurements, which considers the vertical entrainment of residual layers and the variability in the soil radon exhalation rate. The potential issues in using progeny instead of radon have been solved from both a theoretical and experimental perspective; furthermore, the instrumental efficiency and the counting scheme have been included in the model. The applicability range of the box model has been defined by comparing radon-derived estimates with sodar and lidar data. Three intervals have been analyzed ("near-stable", "transition" and "turbulent"), and different processes have been characterized. We describe a preliminary application case performed in Rome, Italy, while case studies will be required to determine the range limits that can be applied in any circumstances.

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

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

    PubMed

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

    2014-08-01

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

  10. Microdosimetric approach to the problem of lung cancer induced by radon progeny

    SciTech Connect

    Sedlak, A.

    1996-05-01

    The increased risk of lung cancer arising from chronic exposure to radon progeny in Czech uranium mines was analyzed on the basis of specific energy distributions for basal and secretory cell nuclei. The distributions were calculated from published results of lung microdosimetry. Whereas classical concepts consider that cell nuclei are hit one or more times by alpha particle tracks, the microdosimetry is able to distinguish glancing (non-lethal, possibly carcinogenic) hits from alpha particle traversals near to nucleus center (which probably inactivate the cell). The simple microdosimetric model differentiates both cases by the quantity termed boundary specific energy. The importance of some confounding factors is examined. Particularly the continuous replacement of bronchial epithelium cells by the new ones is worth considering. Still, the lung cancer frequency seems to be related to the number of sensitive cells with glancing hits. This might be a relevant argument to the toxicity of radon progeny. The central idea of the model, the boundary specific energy, was tested on the basis of radiobiological experiments with isolated cell lines. 49 refs., 6 figs., 1 tab.

  11. "Deposition-flux to lung dose"--a new approach in radon inhalation dosimetry using wire-mesh capped direct radon progeny sensor.

    PubMed

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

    2014-12-01

    Assigning indoor radon doses to populations based on the widely used, cumulative radon concentration monitoring techniques is beset with errors arising due to uncertain equilibrium factors and unattached fractions. Moreover, the dose conversion factor (DCF) of radon decay products may vary by a factor of ∼40 within the particle size range from ∼0.5 nm to tens of micrometers. An ideal detector should have a response, which closely mimics the strong dependence of the DCF on the particle size. In this context, we propose a new approach in which the doses are computed directly from the time integrated progeny deposition fluxes on a suitably tailored surrogate surface. The deposition on this wire-mesh capped detector system closely mimics the deposition rate in human respiratory tract. The detection unit consists of an optimally designed wire-mesh capped Direct Radon Progeny Sensor (DRPS) system. Of the different wire-mesh types, 100 mesh types were found to be suitable considering the fine and coarse fraction penetration efficiencies. The calibration factor was theoretically derived as 0.0077 {mSv (Tracks cm(-2))(-1)}, for converting the measured atom flux in the 100-mesh capped DRPS system to inhalation dose attributed to radon progeny.

  12. Dosimetry modelling of transient radon and progeny concentration peaks: results from in situ measurements in Ikaria spas, Greece.

    PubMed

    Nikolopoulos, Dimitrios; Vogiannis, Efstratios; Petraki, Ermioni; Kottou, Sofia; Yannakopoulos, Panayiotis; Leontaridou, Maria; Louizi, Anna

    2013-06-01

    Radon and progeny ((218)Po, (214)Pb, (214)Bi and (214)Po) are radioactive indoor pollutants recognised for the human radiation burden that they induce. Bathing in thermal spas causes transient concentration peaks of radon and progeny and additional short-term impact in patients and personnel. This paper reports a semi-empirical non-linear first order model for describing radon and progeny variations in treatment rooms of the Ikaria spas. Non-measured physical parameters were estimated from in situ measurements in Ikaria through non-linear numerical solving. Exposure and dose variations were additionally modelled. Attachment rate constants were found to be between 0.44 and 55 h(-1). Deposition rate constants were between 0.28 and 7.3 h(-1) for attached nuclei and 0.42 and 64 h(-1) for unattached nuclei. Unattached progeny peaks were right-shifted compared to those of radon. Modelled effective doses ranged between 0.001 mSv per year and 0.589 mSv per year for patients and between 0.001 mSv per year and 18.9 mSv per year for workers. Apollon spas presented quite high doses. These were the highest reported in Greece and are significant worldwide.

  13. 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.

  14. Mutation rates at the glycophorin A and HPRT loci in uranium miners exposed to radon progeny.

    PubMed Central

    Shanahan, E M; Peterson, D; Roxby, D; Quintana, J; Morely, A A; Woodward, A

    1996-01-01

    OBJECTIVES--To find whether a relation exists between estimated levels of exposure to radon and its progeny and mutations in hypoxanthine phosphoribosyl transferase (HPRT) and glycophorin A in a cohort of former uranium miners. METHODS--A cohort study involving a sample of miners from the Radium Hill uranium mine in South Australia, which operated from 1952 to 1961. Radiation exposures underground at Radium Hill were estimated from historical radon gas measures with a job exposure matrix. Workers from the mine who worked exclusively above ground according to mine records were selected as controls. In 1991-2 miners were interviewed and blood taken for measurement of somatic mutations. Mutation rates for HPRT and glycophorin A were estimated with standard assay techniques. RESULTS--Homozygous mutations of glycophorin A were increased in underground miners (P = 0.0027) and the mutation rate tended to rise with increasing exposure with the exception of the highest exposure (> 10 working level months). However, there was no association between place of work and either the hemizygous mutations of glycophorin A or the HPRT mutation. CONCLUSIONS--There may be an association between glycophorin A mutations and previous occupational exposure to ionising radiation. However, not enough is known at present to use these assays as biomarkers for historical exposure in underground mining cohorts. PMID:8704866

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

    PubMed

    Sannappa, J; Ningappa, C

    2014-03-01

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

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

    PubMed

    Sannappa, J; Ningappa, C

    2014-03-01

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

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

    SciTech Connect

    Hopke, P.K.

    1996-09-01

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

  18. A method of discriminating transuranic radionuclides from radon progeny using low-resolution alpha spectroscopy and curve-fitting techniques.

    PubMed

    Konzen, Kevin; Brey, Richard

    2012-05-01

    ²²²Rn (radon) and ²²⁰Rn (thoron) progeny are known to interfere with determining the presence of long-lived transuranic radionuclides, such as plutonium and americium, and require from several hours up to several days for conclusive results. Methods are proposed that should expedite the analysis of air samples for determining the amount of transuranic radionuclides present using low-resolution alpha spectroscopy systems available from typical alpha continuous air monitors (CAMs) with multi-channel analyzer (MCA) capabilities. An alpha spectra simulation program was developed in Microsoft Excel visual basic that employed the use of Monte Carlo numerical methods and serial-decay differential equations that resembled actual spectra. Transuranic radionuclides were able to be quantified with statistical certainty by applying peak fitting equations using the method of least squares. Initial favorable results were achieved when samples containing radon progeny were decayed 15 to 30 min, and samples containing both radon and thoron progeny were decayed at least 60 min. The effort indicates that timely decisions can be made when determining transuranic activity using available alpha CAMs with alpha spectroscopy capabilities for counting retrospective air samples if accompanied by analyses that consider the characteristics of serial decay.

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

    PubMed

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

    2011-03-15

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

  20. The Effect of Ultrafine Aerosol (0.5 to 50 NM (0.05 Micrometers)) on the Deposition of Radon Progeny in Human Lungs and Implications for the Measurement of Exposure.

    NASA Astrophysics Data System (ADS)

    Schmalbeck, Linda Michaels

    1995-01-01

    Despite a generally acknowledged public health risk from indoor exposure to airborne radon progeny, measurement techniques in current use do not provide sufficient information to assess risk from exposures in the home. By contrast, a simple, direct, measurement (the working level month) is a reliable starting point for the evaluation of miners' risks from radon progeny exposure. Ultrafine particles (0.5 to 50 nm in diameter) are frequently present in room air, especially during high occupancy times when activities like cooking and cleaning are taking place; but they are virtually absent from mine air. Measurement techniques used to evaluate mine and indoor air exposures do not supply any size-based data. Few studies of ultrafine aerosol deposition in humans have been undertaken, and none of these has specifically examined ultrafine particle deposition in the radiosensitive bronchial region of the respiratory tract. In this research, the effect of ultrafine aerosol on radon progeny deposition in the bronchial airways was studied using: (1) a unique human exposure data base involving 8 men and 4 women volunteers, (2) a mathematical model describing the attachment behavior of radon progeny in the presence of aerosol developed as part of this work, and (3) a human respiratory-tract deposition model. The addition of ultrafine aerosol to the air breathed by human subjects more than doubled the amount of radon progeny activity deposited in the bronchial region of the subjects' lungs, although radon gas concentration was held constant during all exposure experiments. The gamma activity measured in vivo remained higher at all times after exposure to ultrafine aerosol, while the rate of gamma activity clearance from the region was, on average, about 40 percent faster following ultrafine aerosol exposure. The human exposure data demonstrated that some aerosol size information is crucial to the determination of regional lung deposition and, consequently, the calculation of

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

  2. 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

  3. Mutation induction by inhaled radon progeny modeled at the tissue level.

    PubMed

    Madas, Balázs G; Balásházy, Imre

    2011-11-01

    The observable responses of living systems to ionizing radiation depend on the level of biological organization studied. Understanding the relationships between the responses characteristic of the different levels of organization is of crucial importance. The main objective of the present study is to investigate how some cellular effects of radiation manifest at the tissue level by modeling mutation induction due to chronic exposure to inhaled radon progeny. For this purpose, a mathematical model of the bronchial epithelium was elaborated to quantify cell nucleus hits and cell doses. Mutagenesis was modeled considering endogenous as well as radiation-induced DNA damages and cell cycle shortening due to cell inactivation. The model parameters describing the cellular effects of radiation are obtained from experimental data. Cell nucleus hits, cell doses, and mutation induction were computed for the activity hot spots of the large bronchi at different exposures. Results demonstrate that the mutagenic effect of densely ionizing radiation is dominated by cell cycle shortening due to cell inactivation and not by DNA damages. This suggests that radiation burdens of non-progenitor cells play a significant role in mutagenesis in case of protracted exposures to densely ionizing radiation. Mutation rate as a function of dose rate exhibits a convex shape below a threshold. This threshold indicates the exhaustion of the tissue regeneration capacity of local progenitor cells. It is suggested that progenitor cell hyperplasia occurs beyond the threshold dose rate, giving a possible explanation of the inverse dose-rate effect observed in the epidemiology of lung cancer among uranium miners.

  4. Probability of causation for lung cancer after exposure to radon progeny: A comparison of models and data

    SciTech Connect

    Chmelevsky, D.; Barclay, D.; Kellerer, A.M. |; Tomasek, L.; Kunz, E.; Placek, V.

    1994-07-01

    The estimates of lung cancer risk due to the exposure to radon decay products are based on different data sets from underground mining and on different mathematical models that are used to fit the data. Diagrams of the excess relative rate per 100 working level months in its dependence on age at exposure and age attained are shown to be a useful tool to elucidate the influence that is due to the choice of the model, and to assess the differences between the data from the major western cohorts and those from the Czech uranium miners. It is seen that the influence of the choice of the model is minor compared to the difference between the data sets. The results are used to derive attributable lifetime risks and probabilities of causation for lung cancer following radon progeny exposures. 23 refs., 9 figs.

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

    PubMed

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

    2012-11-01

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

  6. Use of naturally occurring radon progeny for in-place testing of high-efficiency particulate air filters

    SciTech Connect

    Newton, G.J.; Hoover, M.D.; Yeh, Hsu-Chi

    1997-12-01

    High-efficiency particulate air (HEPA) filters are routinely used to control emissions of radioactive particles from nuclear facilities. Because HEPA filters play a critical role in protecting members of the public and the environment, there are stringent requirements for verifying the efficiency of HEPA filters prior to their installation and during their use. Traditional methods for the performance tests involve introducing a challenge aerosol before the filter and comparing the concentration of particles before and after the filter. We describe a proof-of-principle test for evaluating use of naturally occurring radon progeny for testing HEPA filters.

  7. Stochastic rat lung dosimetry for inhaled radon progeny: a surrogate for the human lung for lung cancer risk assessment.

    PubMed

    Winkler-Heil, R; Hussain, M; Hofmann, W

    2015-05-01

    Laboratory rats are frequently used in inhalation studies as a surrogate for human exposures. The objective of the present study was therefore to develop a stochastic dosimetry model for inhaled radon progeny in the rat lung, to predict bronchial dose distributions and to compare them with corresponding dose distributions in the human lung. The most significant difference between human and rat lungs is the branching structure of the bronchial tree, which is relatively symmetric in the human lung, but monopodial in the rat lung. Radon progeny aerosol characteristics used in the present study encompass conditions typical for PNNL and COGEMA rat inhalation studies, as well as uranium miners and human indoor exposure conditions. It is shown here that depending on exposure conditions and modeling assumptions, average bronchial doses in the rat lung ranged from 5.4 to 7.3 mGy WLM(-1). If plotted as a function of airway generation, bronchial dose distributions exhibit a significant maximum in large bronchial airways. If, however, plotted as a function of airway diameter, then bronchial doses are much more uniformly distributed throughout the bronchial tree. Comparisons between human and rat exposures indicate that rat bronchial doses are slightly higher than human bronchial doses by about a factor of 1.3, while lung doses, averaged over the bronchial (BB), bronchiolar (bb) and alveolar-interstitial (AI) regions, are higher by about a factor of about 1.6. This supports the current view that the rat lung is indeed an appropriate surrogate for the human lung in case of radon-induced lung cancers. Furthermore, airway diameter seems to be a more appropriate morphometric parameter than airway generations to relate bronchial doses to bronchial carcinomas.

  8. Lung exposure from inhalation of radon progeny: Calculated from in vivo measurements of {sup 210}Pb in the skull

    SciTech Connect

    Laurer, G.R.; Cohen, N.; Estrada, J.J.S.

    1999-04-01

    To calculate the radiation dose to the lungs from the inhalation of radon and its short-lived progeny, an accurate estimate of cumulative exposure is necessary. In this preliminary study, the content of {sup 210}Pb in the skeleton is used to obtain a measure of integrated exposure to the lungs of people living in homes with above average concentrations of radon. Measurements of skeletal {sup 210}Pb made in vivo allow the exposed individuals to become, in effect, their own samplers and dosimeters through the normal physical and physiological processes of inhalation, deposition, and retention. {sup 210}Pb measurements have been made on 40 subjects whose homes have above average levels of radon. These data are used to obtain their cumulative lung exposures, defined as RLM (Respiratory Level Months). RLM is calculated from the numbers of atoms of RaA, RaB, and RaC,C{prime} deposited in their respiratory systems over the time periods lived in the surveyed homes. The RLM values obtained are not significantly different than conventional WLM exposures calculated for the same time periods.

  9. Simultaneous measurements of radon and thoron, and their progeny levels in dwellings on anticlinal structures of Assam, India.

    PubMed

    Barooah, Debajyoti; Barman, Simi; Phukan, Sarat

    2014-06-01

    Radon and thoron, and their progeny concentrations along with equilibrium factors for gas progeny and radiological risks to the residents have been measured in dwellings of Digboi and Mashimpur areas located on anticlines during the winter season. In this present investigation, twin-cup dosemeters fitted with LR-115 (II) nuclear detectors have been employed. The present work has shown that there exist considerable house-to-house variations in values with maximum values in mud houses and minimum values in assam type (AT) houses. It has been found that mean (and geometric standard deviations (GSD)) radon concentrations are 83.8 (1.3), 113.5 (1.1) and 157.2 (1.2) Bq m(-3) in AT, reinforced cement concrete (RCC) and mud houses in Digboi area and 63.0 (1.1), 87.1 (1.4) and 182.1 (1.2) Bq m(-3) in AT, RCC and mud houses in Mashimpur area, respectively. The overall mean radon concentrations in Digboi and Mashimpur are estimated to be 114.4 (1.4) and 100.0 (1.7) Bq m(-3). The mean radon concentrations are found to be less than the lower reference level of 200 Bq m(-3) of the International Commission on Radiological Protection (ICRP 2007). The thoron concentrations in Digboi area are estimated to be 31.1 (1.3), 50.8 (1.4) and 67.0 (1.6) Bq m(-3) in AT, RCC and mud houses, respectively, whereas in Mashimpur area, the thoron concentrations are estimated to be 26.4 (1.3), 44.4 (1.3) and 77.7 (1.3) Bq m(-3) in AT, RCC and mud houses, respectively. The mean annual effective doses in Digboi area are found to be 1.9 (1.3), 2.7 (1.2) and 4.1 (1.4) mSv y(-1) in AT, RCC and mud houses, respectively, while in the case of Mashimpur area, the mean annual effective doses are found to be 1.5 (1.4), 2.2 (1.2) and 4.9 (1.3) mSv y(-1) in AT, RCC and mud houses, respectively. Nevertheless, the obtained results are much lower than the upper reference level of 10 mSv (ICRP 2007). PMID:24469015

  10. Detection of 210Po on filter papers 16 years after use for the collection of short-lived radon progeny in a room.

    PubMed

    Abu-Jarad, F; Fazal-ur-Rehman

    2003-01-01

    Radon gas was allowed to accumulate in its radium source and then injected into a 36 m(3) test room, resulting in an initial radon concentration of 15 kBq m(-3). Filter papers were used to collect the short-lived radon progeny and thus to measure the Potential Alpha Energy Concentration (PAEC) in-situ in the year 1984 at different times and conditions according to the experimental design. The radon progeny collected on the filter papers were studied as a function of aerosol particle concentration ranging from 10(2)-10(5) particles cm(-3) in three different experiments. The highest aerosol particle concentration was generated by indoor cigarette smoking. Those filters were stored after the experiment, and were used after 16 years to study the activity of the radon long-lived alpha emitter progeny, (210)Po (T(1/2)=138 days). This isotope is separated from the short-lived progeny by (210)Pb beta emitter with 22.3 years half-life. After 16 years' storage of these filters, each filter paper was sandwiched and wrapped between two CR-39 nuclear track detectors, to put the detectors in contact with the surfaces of different filters, for 337 days. Correlation between the PAEC measured using filter papers in the year 1984 and the activity of long-lived alpha emitter (210)Po on the same filter papers measured in the year 2000 were studied. The results of the (210)Po activity showed a very good correlation of 0.92 with the PAEC 16 years ago. The results also depict that the PAEC and (210)Po activity in indoor air increased with the increase of aerosol particle concentration, which shows the attachment of short-lived radon progeny with the aerosol particles. The experiment proves that indoor cigarette smoking is a major source of aerosol particles carrying radon progeny and, thus, indoor cigarette smoking is an additional source of internal radiation hazard to the occupants whether smoker or non-smoker.

  11. Airborne gamma ray surveying in radon hazard evaluation: a case study from Norway

    NASA Astrophysics Data System (ADS)

    Smethurst, Mark A.; Liv Rudjord, Anne; Finne, Ingvild

    2010-05-01

    The Geological Survey of Norway and Norwegian Radiation Protection Authority have established an approach to mapping radon hazards in Norway based on direct measurements of radon in indoor air, bedrock and drift geology mapping, and the mapping of radium in the ground using helicopter- and aeroplane-borne gamma-ray surveys. Existing indoor radon measurements are used to establish hazard profiles for the other three data sets. The multiple indications of hazard, from all four data sets, are then combined into a single hazard prognosis map. We have looked closely at the efficiency of the mapping method in the municipality of Gran (north of Oslo). The uranium rich alum shale and superficial deposits associated with it are the principal sources of indoor radon in the area. Small isolated granite bodies and local high permeability glacio-fluvial deposits contribute to the hazard picture. The method produces a liberal hazard map that encloses most of the known areas of severe radon contamination in dwellings and identifies additional uninhabited areas where similar levels of contamination can be expected (without mitigating action). The hazard evaluation in the Gran area is 81% efficient at enclosing high indoor radon measurements in the high hazard zone when this zone occupies 50% of the total geographic area. The probability of this distribution happening by chance is 0.054%. Of course, indoor radon measurements are the most valuable data set for establishing radon hazard levels accurately, but only where these measurements are abundant. In Norway such areas are very limited in spatial extent. We find airborne measurements to be the most effective supplementary data, followed in usefulness by knowledge of the bedrock geology and drift geology (at the 1:50,000 mapping scale). A further opportunity to test and refine our approach to radon hazard evaluation presents itself now with a new airborne gamma-ray survey over the Kongsberg region southwest of Oslo. The survey is

  12. Design and construct optimum dosimeter to detect airborne radon and thoron gas: Experimental study

    NASA Astrophysics Data System (ADS)

    Ismail, Asaad H.; Jaafar, Mohamad S.

    2011-02-01

    Aim of this work is to design and select optimum dimension of a radon and thoron dosimeter within the measure optimum value of the calibration factor, using CR-39 Nuclear Track Detectors (NTDs). The results show that the best dimension to detect and measure real values of airborne radon and thoron concentrations is 6 cm and 7 cm for diameter and height, respectively. Calibration factors (K) for radon and thoron at this dimension were 2.68 ± 0.03 cm and 0.83 ± 0.01 cm, respectively, and these factors relatively depend on the detector efficiency. Therefore, the efficiency of CR-39NTDs to register alpha particles and their effects on the calibration factor estimated. It is found that the calibration factor increased exponentially with detector efficiency. Moreover, detector efficiency was equal to 80.3 ± 1.23% at the optimum dosimeter.

  13. Modifiers of exposure--response estimates for lung cancer among miners exposed to radon progeny

    SciTech Connect

    Hornung, R.W.; Deddens, J.; Roscoe, R.

    1995-03-01

    The association between lung cancer and exposure to radon decay products has been well established. Despite agreement on this point, there is still some degree of uncertainty regarding characteristics of the exposure-response relationship. The use of studies of underground miners to estimate lung cancer risks due to residential radon exposure depends upon a better understanding of factors potentially modifying the exposure-response relationship. Given the diversity in study populations regarding smoking status, mining conditions, risk analysis methodology, and referent populations, the risk estimates across studies are quite similar. However, several factors partially contributing to differences in risk estimates are modified by attained age, time since last exposure, exposure rate, and cigarette smoking patterns. There is growing agreement across studies that relative risk decreases with attained age and time since last exposure. Several studies have also found an inverse exposure-rate effect, i.e., low exposure rates for protracted duration of exposure are more hazardous than equivalent cumulative exposures received at higher rates for shorter periods of time. Additionally, the interaction between radon exposure and cigarette smoking appears to be intermediate between additive and multiplicative in a growing number of studies. Quantitative estimates of these modifying factors are given using a new analysis of data from the latest update of the Colorado Plateau uranium miners cohort. 24 refs., 3 figs., 4 tabs.

  14. Risk assessment of exposure to waterborne and airborne radon-222 in Illinois. Final report

    SciTech Connect

    Hallenbeck, W.H.

    1987-12-01

    This study analyzed epidemiological and experimental animal studies in order to develop exposure-response relationships for radon-induced cancer. These relationships were used to estimate lifetime risks and annual excess cases based on the available waterborne and airborne data for Illinois. Exceedances of the USEPA action level of 4pCi/l occurred in 13% of 303 first-floor measurements and 43% of 1094 basement measurements. For waterborne radon, the highest lifetime risk of cancer mortality associated with an Illinois groundwater-based drinking water system was estimated to be 4 x 104. The number of excess cases of fatal cancer generated per year in Illinois was estimated to be about six. For airborne radon, a tentative value of 0.9 pCi/l (for first floors), derived from the limited existing data, was used to estimate the average lifetime lung-cancer mortality risk and the number of excess cases of fatal lung cancer generated per year. The average lifetime lung-cancer mortality risk was estimated to be 0.0048, and the annual number of excess cases of fatal lung cancer was estimated to be 784. Due to the nature of the underlying exposure-response relationships for radon-induced cancer, the values presented most likely represent upper-bound estimates.

  15. 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.

  16. An automated, semi-continuous system for measuring indoor radon progeny activity-weighted size distributions, d sub p : 0. 5--500 nm

    SciTech Connect

    Li, Chih-Shan; Hopke, P.K.; Ramamurthi, M.

    1990-05-01

    A system for the detection and measurement of indoor radon progeny activity-weighted size distributions (particle size, d{sub p} > 0.5 nm) and concentration levels has been developed. The system is microcomputer-controlled and involves a combination of multiple wire screen (Graded Screen Array) sampler-detector units operated in parallel. The radioactivity sampled in these units permits the estimation of the radon progeny activity-weighted size distributions and concentration levels on a semi-continuous basis. This paper presents details of the system and describes various stages in the development of the system. Results of field measurements in a residential environment are presented to illustrate the resolution, sensitivity and capabilities of the measurement system. 16 refs., 4 figs., 1 tab.

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

    SciTech Connect

    Hopke, P.K.

    1993-01-01

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

  18. International intercalibration and intercomparison measurements of radon progeny particle size distribution

    SciTech Connect

    Tu, Keng-Wu

    1997-07-01

    Because there is no standard method for {sup 222}Rn progeny size measurements, verifying the performance of various measurement techniques is important. This report describes results of an international intercomparison and calibration of {sup 222}Rn progeny size measurements involving low pressure impactors (MOUDI and Berner) and diffusion battery systems, as well as both alpha- and gamma- counting methods. The intercomparison was at EML on June 12-15, 1995. 5 different particle sizes (80, 90, 165, 395, 1200 nm) of near monodisperse condensation Carbauba wax aerosol and 2 bimodal size spectra (160 and 365 nm, and 70 and 400 nm) were used. 20 tests were completed, covering both low and high concentrations of {sup 222}Rn and test aerosols. For the single-mode test aerosol, the measurements agreed within the size range. Best agreement was found between the two low pressure impactors. Some differences between the impactor and diffusion battery methods were observed in the specific peak locations and the resultant geometric mean diameters. For the two bimodal size distribution aerosols, the MOUDI measurements showed two modes, while the other 3 devices showed a single mode size distribution.

  19. 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 ...

  20. Development and application of a complex numerical model and software for the computation of dose conversion factors for radon progenies.

    PubMed

    Farkas, Árpád; Balásházy, Imre

    2015-04-01

    A more exact determination of dose conversion factors associated with radon progeny inhalation was possible due to the advancements in epidemiological health risk estimates in the last years. The enhancement of computational power and the development of numerical techniques allow computing dose conversion factors with increasing reliability. The objective of this study was to develop an integrated model and software based on a self-developed airway deposition code, an own bronchial dosimetry model and the computational methods accepted by International Commission on Radiological Protection (ICRP) to calculate dose conversion coefficients for different exposure conditions. The model was tested by its application for exposure and breathing conditions characteristic of mines and homes. The dose conversion factors were 8 and 16 mSv WLM(-1) for homes and mines when applying a stochastic deposition model combined with the ICRP dosimetry model (named PM-A model), and 9 and 17 mSv WLM(-1) when applying the same deposition model combined with authors' bronchial dosimetry model and the ICRP bronchiolar and alveolar-interstitial dosimetry model (called PM-B model). User friendly software for the computation of dose conversion factors has also been developed. The software allows one to compute conversion factors for a large range of exposure and breathing parameters and to perform sensitivity analyses.

  1. Characterization of Radon Progeny in EXO-200 Using Machine Learning Algorithms

    NASA Astrophysics Data System (ADS)

    Smith, Erica

    Neutrinoless double beta decay (0nubetabeta) is a rare, second-order process that occurs in certain isotopes for which beta decay is energetically forbidden. EXO-200 is a 0nubetabeta experiment with 110 kg of active liquid xenon (LXe) isotopically enriched in 136Xe. EXO-200 detects events using a combination of scintillation and ionization signals, which allows for excellent particle discrimination. However, events with a low ionization signal cannot be fully characterized with the current analysis framework. To fill in these gaps, we introduce a boosted decision tree regressor as a new tool to characterize events in the detector. We focus on alpha decays of 222Rn and its progeny, which have low ionization signals that often fall below the threshold for position reconstruction. Using information gained from this technique, we confirm previous results for the 218Po ion velocity and improve previous results for the 218Po ionization fraction. We also investigate events that occur near the walls of the vessel. These events have no ionization signal and therefore cannot be characterized with any existing technique in the analysis framework. By investigating these events we determine that they are not distributed uniformly throughout the detector, which may point to charging up of the plastics inside the LXe vessel or a "hot spot'' on the plastic due to contamination during cleaning and installation.

  2. 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.

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

    NASA Astrophysics Data System (ADS)

    Dey, Gautam Kumar; Das, Projit Kumar

    2012-02-01

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

  4. 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 ...

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

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

  6. Coagulation effect on the activity size distributions of long lived radon progeny aerosols and its application to atmospheric residence time estimation techniques.

    PubMed

    Anand, S; Mayya, Y S

    2015-03-01

    The long lived naturally occurring radon progeny species in the atmosphere, namely (210)Pb, (210)Bi and (210)Po, have been used as important tracers for understanding the atmospheric mixing processes and estimating aerosol residence times. Several observations in the past have shown that the activity size distribution of these species peaks at larger particle sizes as compared to the short lived radon progeny species - an effect that has been attributed to the process of coagulation of the background aerosols to which they are attached. To address this issue, a mathematical equation is derived for the activity-size distribution of tracer species by formulating a generalized distribution function for the number of tracer atoms present in coagulating background particles in the presence of radioactive decay and removal. A set of these equations is numerically solved for the progeny chain using Fuchs coagulation kernel combined with a realistic steady-state aerosol size spectrum that includes nucleation, accumulation and coarse mode components. The important findings are: (i) larger shifts in the modal sizes of (210)Pb and (210)Po at higher aerosol concentrations such as that found in certain Asian urban regions (ii) enrichment of tracer specific activity on particles as compared to that predicted by pure attachment laws (iii) sharp decline of daughter-to-parent activity ratios for decreasing particle sizes. The implication of the results to size-fractionated residence time estimation techniques is highlighted. A coagulation corrected graphical approach is presented for estimating the residence times from the size-segregated activity ratios of (210)Bi and (210)Po with respect to (210)Pb. The discrepancy between the residence times predicted by conventional formula and the coagulation corrected approach for specified activity ratios increases at higher atmospheric aerosol number concentrations (>10(10) #/m(3)) for smaller sizes (<1 μm). The results are further

  7. Coagulation effect on the activity size distributions of long lived radon progeny aerosols and its application to atmospheric residence time estimation techniques.

    PubMed

    Anand, S; Mayya, Y S

    2015-03-01

    The long lived naturally occurring radon progeny species in the atmosphere, namely (210)Pb, (210)Bi and (210)Po, have been used as important tracers for understanding the atmospheric mixing processes and estimating aerosol residence times. Several observations in the past have shown that the activity size distribution of these species peaks at larger particle sizes as compared to the short lived radon progeny species - an effect that has been attributed to the process of coagulation of the background aerosols to which they are attached. To address this issue, a mathematical equation is derived for the activity-size distribution of tracer species by formulating a generalized distribution function for the number of tracer atoms present in coagulating background particles in the presence of radioactive decay and removal. A set of these equations is numerically solved for the progeny chain using Fuchs coagulation kernel combined with a realistic steady-state aerosol size spectrum that includes nucleation, accumulation and coarse mode components. The important findings are: (i) larger shifts in the modal sizes of (210)Pb and (210)Po at higher aerosol concentrations such as that found in certain Asian urban regions (ii) enrichment of tracer specific activity on particles as compared to that predicted by pure attachment laws (iii) sharp decline of daughter-to-parent activity ratios for decreasing particle sizes. The implication of the results to size-fractionated residence time estimation techniques is highlighted. A coagulation corrected graphical approach is presented for estimating the residence times from the size-segregated activity ratios of (210)Bi and (210)Po with respect to (210)Pb. The discrepancy between the residence times predicted by conventional formula and the coagulation corrected approach for specified activity ratios increases at higher atmospheric aerosol number concentrations (>10(10) #/m(3)) for smaller sizes (<1 μm). The results are further

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

    PubMed

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

    2011-06-01

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

  9. Daily variation of radon gas and its short-lived progeny concentration near ground level and estimation of aerosol residence time

    NASA Astrophysics Data System (ADS)

    M, Mohery; A, M. Abdallah; A, Ali; S, S. Baz

    2016-05-01

    Atmospheric concentrations of radon (222Rn) gas and its short-lived progenies 218Po, 214Pb, and 214Po were continuously monitored every four hours at the ground level in Jeddah city, Kingdom of Saudi Arabia. The measurements were performed three times every week, starting from November 2014 to October 2015. A method of electrostatic precipitation of positively charged 218Po and 214Po by a positive voltage was applied for determining 222Rn gas concentration. The short-lived 222Rn progeny concentration was determined by using a filter holder connected with the alpha-spectrometric technique. The meteorological parameters (relative air humidity, air temperature, and wind speed) were determined during the measurements of 222Rn and its progeny concentrations. 222Rn gas as well as its short-lived progeny concentration display a daily and seasonal variation with high values in the night and early morning hours as compared to low values at noon and in the afternoon. The observed monthly atmospheric concentrations showed a seasonal trend with the highest values in the autumn/winter season and the lowest values in the spring/summer season. Moreover, and in parallel with alpha-spectrometric measurements, a single filter-holder was used to collect air samples. The deposited activities of 214Pb and the long-lived 222Rn daughter 210Pb on the filter were measured with the gamma spectrometric technique. The measured activity concentrations of 214Pb by both techniques were found to be relatively equal largely. The highest mean seasonally activity concentrations of 210Pb were observed in the autumn/winter season while the lowest mean were observed in the spring/summer season. The mean residence time (MRT) of aerosol particles in the atmospheric air could be estimated from the activity ratios of 210Pb/214Pb. Project supported by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah (Grant No. 291/965/1434).

  10. Aerosols: unexpected disequilibrium phenomena between airborne radio activities of lead-210 and its progenies bismuth-210 and polonium-210.

    PubMed

    Wallner, Gabriele; Berner, Axel; Irlweck, Karl

    2002-12-01

    For the first time, concentrations of the long lived radon progenies (210)Pb, (210)Bi and (210)Po were measured in the mine atmosphere of the so called "healing gallery" in Badgastein, Austria, a region famous for its radioactive springs. These investigations were performed in order to study the radioactive equilibrium between the (210)Pb-(210)Bi and the (210)Pb-(210)Po pairs so as to gain more information about the aerosol-forming processes in the mine. The particle size distribution of the aerosols was determined under different ventilation conditions. Six-stage and eight-stage cascade impactors with working ranges from 0.15 to 5 micro m and from 0.063 to 8 micro m, respectively, were used to collect the mine aerosols. These samples were analysed in the laboratory and measured by liquid scintillation spectrometry. The most surprising results were found under full ventilation, when the total activity concentrations of (210)Pb, (210)Bi and (210)Po were 4.6, 2.0 and 16.5 mBq/m(3), respectively. In this case (210)Po/(210)Pb activity ratios ranged between 1.8+/-0.3 and 4.3+/-0.3. These unexpected results were confirmed by the eight-stage impactor samples. For the smallest particles, between 0.062 and 0.125 micro m, an even higher value of 7.5 was observed. As outside sources could be excluded, such (210)Po enrichments must occur during the aerosol-forming process itself inside the mine.

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

    NASA Astrophysics Data System (ADS)

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

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

  12. The biological effectiveness of radon-progeny alpha particles. II. Oncogenic transformation as a function of linear energy transfer

    SciTech Connect

    Miller, R.C.; Marino, S.A.; Brenner, D.J.

    1995-04-01

    Epidemiological studies have established an association between exposure to radon and carcinoma of the lung. However, based on data for either lung cancer in uranium miners exposed to radon or bronchial epithelial carcinomas in Japanese A-bomb survivors, it has not been possible to assign estimates of risk of lung cancer for the general population exposed to radon in their homes. Based on past success with the excellent quantitative properties of the C3H 10T1/2 in vitro oncogenic transformation assay system, the relative biological effectiveness (RBE) for radiation-induced transformation for charged particles of defined LET has been determined. As the LET of the radiation was increased, the rate of induction of oncogenic transformation increased and the RBE{sub m} approached 20. At higher LETs, RBE dropped precipitously. The rapid drop in effectiveness for {alpha} particles with LETs between 120 and 265 KeV/{mu}m implies a lower quality factor than the 20-25 currently considered appropriate when estimating lung cancer mortality. 29 refs., 3 figs., 21 tabs.

  13. Biophysical modelling of the effects of inhaled radon progeny on the bronchial epithelium for the estimation of the relationships applied in the two-stage clonal expansion model of carcinogenesis.

    PubMed

    Madas, Balázs G; Varga, Katalin

    2014-06-01

    There is a considerable debate between research groups applying the two-stage clonal expansion model for lung cancer risk estimation, whether radon exposure affects initiation and transformation or promotion. The aim of the present study is to quantify the effects of radon progeny on these stages with biophysical models. For this purpose, numerical models of mutation induction and clonal growth were applied in order to estimate how initiation, transformation and promotion rates depend on tissue dose rate. It was found that rates of initiation and transformation increase monotonically with dose rate, whereas effective promotion rate decreases with time but increases sublinearly with dose rate. Despite the uncertainty of results due to the lack of experimental data, present study suggests that effects of radon exposure on both mutational events and clonal growth are significant and should be considered in mechanistic models of carcinogenesis applied for analysing epidemiological data.

  14. 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.

  15. Effect of electrostatic space charge on reduction of airborne transmission of Salmonella and other bacteria in broiler breeders in production and their progeny.

    PubMed

    Richardson, L J; Hofacre, C L; Mitchell, B W; Wilson, J L

    2003-01-01

    Salmonella in birds is a concern because of the human foodborne illness associated with the consumption of poultry meat and eggs. One of the methods of transmission of Salmonella within a flock can be by the air. Therefore, we used reduction of transmission of Salmonella to monitor the effectiveness of the electrostatic space charge system (ESCS). During the average broiler breeder laying cycle of 40 wk, a large amount of dust becomes airborne and accumulates on walls, ceiling, and equipment. Many microorganisms adhere to these dust particles, making dust an excellent vector for horizontal disease transmission between birds. We used two environmentally controlled rooms containing commercial broiler breeders to evaluate the effectiveness of an ESCS that produced a strong negative electrostatic charge to reduce airborne dust and, subsequently, microorganism levels. The ESCS caused the dust to become negatively charged, therefore moving to the grounded floor in the treatment room. The use of the ESCS resulted in a significant reduction (P < 0.0001, 61% reduction) in airborne dust concentration levels, which resulted in a significant reduction (P < 0.0001, 76% reduction) in total airborne bacteria and gram-negative bacteria (48% reduction) in the treatment room. Significant reductions (P < 0.05) of gram-negative bacteria (63% reduction) on the egg collection belts were also recorded in the treatment room, which resulted in a significant reduction (P < 0.0001) of gram-negative bacteria (28% reduction) on the eggshell surface. The ESCS treatment resulted in fewer Salmonella enteritidis-positive hens and their progeny from the treatment room due to reductions of dust and airborne bacteria. In addition, this significant reduction in bacteria on the eggshell surface should result in less bacteria in the day-old chicks, therefore better early chick livability. There was no significant difference (P > 0.05) in egg production, male or female body weights, mortality, or

  16. 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

  17. 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.

  18. Distribution of Airborne Radon-222 Concentrations in U.S. Homes

    NASA Astrophysics Data System (ADS)

    Nero, A. V.; Schwehr, M. B.; Nazaroff, W. W.; Revzan, K. L.

    1986-11-01

    Apparently large exposures of the general public to the radioactive decay products of radon-222 present in indoor air have led to systematical appraisal of monitoring data from U.S. single-family homes; several ways of aggregating data were used that take into account differences in sample selection and season of measurements. The resulting distribution of annual-average radon-222 concentrations can be characterized by an arithmetic mean of 1.5 picocurie per liter (55 becquerels per cubic meter) and a long tail with 1 to 3% of homes exceeding 8 picocuries per liter, or by a geometric mean of 0.9 picocurie per liter and a geometric standard deviation of about 2.8. The standard deviation in the means is 15%, estimated from the number and variability of the available data sets, but the total uncertainty is larger because these data may not be representative. Available dose-response data suggest that an average of 1.5 picocuries per liter contributes about 0.3% lifetime risk of lung cancer and that, in the million homes with the highest concentrations, where annual exposures approximate or exceed those received by under-ground uranium miners, long-term occupants suffer an added lifetime risk of at least 2%, reaching extraordinary values at the highest concentrations observed.

  19. 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.

  20. 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.

  1. [Radon and domestic exposure].

    PubMed

    Melloni, B; Vergnenègre, A; Lagrange, P; Bonnaud, F

    2000-12-01

    Radon is a noble gas derived from the decay of radium, which itself is a decay product of uranium. The decay products of radon can collect electrostatically on dust particles in the air and, if these particles are inhaled and attach to bronchial epithelium, produce a high local radiation dose. Alpha particles can induce DNA double-strand breaks and the development of cancer. A causal relation between lung cancer and radon exposure and its progeny has been demonstrated in epidemiological studies of miners. Radon exposure became a public health issue almost 15 years ago. Most radon exposure occurs indoors, predominantly in the home. There is however, a wide range of radon concentration values in different countries. The highest level occurs in areas with granite and permeable soils. The risk for smoking, the leading cause of lung cancer, is far greater than for radon, the second leading cause. The estimates obtained from case-control studies of indoor radon are very contradictory. Scientific knowledge of effects of low levels of exposure to radon and the role of cigarette smoking, as a combined factor, must be studied. Smoking and radon probably interact in a multiplicative fashion.

  2. 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.

  3. 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.

  4. The detection and measurement of the electrical mobility size distributions associated with radon decay products

    SciTech Connect

    Fei, Lin

    1996-04-01

    The potential risk of lung cancer has evoked interest in the properties of radon decay products. There are two forms of this progeny: either attached to ambient aerosols, or still in the status of ions/molecules/small clusters. This ``unattached`` activity would give a higher dose per unit of airborne activity than the ``attached`` progeny that are rather poorly deposited. In this thesis, a system for determining unattached radon decay products electrical mobility size distribution by measuring their electrical mobilities was developed, based on the fact that about 88% of {sup 218}Po atoms have unit charge at the end of their recoil after decay from {sup 222}Rn, while the remainder are neutral. Essential part of the setup is the radon-aerosol chamber with the Circular Electrical Mobility Spectrometer (CEMS) inside. CEMS is used for sampling and classifying the charged radioactive clusters produced in the chamber. An alpha- sensitive plastic, CR-39 disk, is placed in CEMS as an inlaid disk electrode and the alpha particle detector. CEMS showed good performance in fine inactive particles` classification. If it also works well for radon decay products, it can offer a convenient size distribution measurement for radioactive ultrafine particles. However, the experiments did not obtain an acceptable resolution. Suggestions are made for solving this problem.

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

    SciTech Connect

    Neuberger, J.S.; Rundo, J.

    1996-12-31

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

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

    SciTech Connect

    Neuberger, J.S.; Rundo, J.

    1996-12-31

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

  7. Air cleaning and radon decay product mitigation

    SciTech Connect

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

    1990-01-01

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

  8. Air cleaning and radon decay product mitigation

    SciTech Connect

    Hopke, P.K.; Li, C.S.; Ramamurthi, M.

    1990-12-31

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

  9. Radon and lung cancer: assessing and mitigating the risk.

    PubMed

    Choi, Humberto; Mazzone, Peter

    2014-09-01

    Radon is a naturally occurring radioactive gas. Its progenies emit alpha particles capable of causing tissue damage. Radon exposure is estimated to be the second most common cause of lung cancer in the United States. Management of patients with a history of radon exposure should involve a lung cancer specialist.

  10. Use of an Existing Airborne Radon Data Base in the Verification of the NASA/AEAP Core Model

    NASA Technical Reports Server (NTRS)

    Kritz, Mark A.

    1998-01-01

    The primary objective of this project was to apply the tropospheric atmospheric radon (Rn222) measurements to the development and verification of the global 3-D atmospheric chemical transport model under development by NASA's Atmospheric Effects of Aviation Project (AEAP). The AEAP project had two principal components: (1) a modeling effort, whose goal was to create, test and apply an elaborate three-dimensional atmospheric chemical transport model (the NASA/AEAP Core model to an evaluation of the possible short and long-term effects of aircraft emissions on atmospheric chemistry and climate--and (2) a measurement effort, whose goal was to obtain a focused set of atmospheric measurements that would provide some of the observational data used in the modeling effort. My activity in this project was confined to the first of these components. Both atmospheric transport and atmospheric chemical reactions (as well the input and removal of chemical species) are accounted for in the NASA/AEAP Core model. Thus, for example, in assessing the effect of aircraft effluents on the chemistry of a given region of the upper troposphere, the model must keep track not only of the chemical reactions of the effluent species emitted by aircraft flying in this region, but also of the transport into the region of these (and other) species from other, remote sources--for example, via the vertical convection of boundary layer air to the upper troposphere. Radon, because of its known surface source and known radioactive half-life, and freedom from chemical production or loss, and from removal from the atmosphere by physical scavenging, is a recognized and valuable tool for testing the transport components of global transport and circulation models.

  11. 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

  12. Effects of overburden, biomass and atmospheric inversions on energy and angular distributions of gamma rays from U, K, Th, and airborne radon sources. Final report

    SciTech Connect

    Rubin, R.M.; Leggett, D.; Wells, M.B.

    1980-12-01

    This report describes a set of radiation transport calculations that were run with the AHISN S/sub n/ discrete ordinates code and a point kernel code to determine the energy, polar angle and height in air distributions of the total and direct gamma-ray flux densities from: (1) uranium sources of 3.2, 200 and 800 ppM in a sandstone orebody covered with biomass densities of 0, 10.2, 20.4, 51.0 and 102.0 kg/m/sup 2/; (2) thorium sources of 12, 25 and 80 ppM in a sandstone ore body covered with biomass densities of 0, 10.2, 20.4, 51.0 and 102.0 kg/m/sup 2/; (3) potassium source (2.5 wt %) in a sandstone ore body covered with biomass densities of 0, 10.2, 20.4, 51.0 and 102.0 kg/m/sup 2/; (4) constant airborne source with height for no inversion and for inversion layer heights of 65.22, 260.32 and 458.43 m; (5) exponentially decreasing airborne source for no inversion and inversion layer heights of 65.22, 260.32 and 458.43 m; (6) 3.2 ppM uranium source in overburden layers of 10.266, 17.110, 26.399 and 32.509 cm thick; (7) 12 ppM thorium source in overburden layers of 10.266, 17.110, 26.399 and 32.509 cm; (8) 2.5 wt % of potassium in overburden layers of 10.266, 17.110, 26.399 and 32.509 cm thick; and (9) 3.2 ppM, 200 ppM, and 800 ppM uranium source in sandstone orebody covered with overburden thicknesses of 10.266, 17.110, 26.399 and 32.509 cm. Gamma-ray emission from the decay of natural uranium, thorium, radon, and potassium are given in a 45-energy group structure applicable to the energy windows used to map the potential uranium ore reserves.

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

    SciTech Connect

    Cross, F.T.

    1992-12-31

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

  14. An improved model for the reconstruction of past radon exposure

    SciTech Connect

    Cauwels, P.; Poffijn, A.

    2000-05-01

    If the behavior of long-lived radon progeny was well understood, measurements of these could be used in epidemiological studies to estimate past radon exposure. Field measurements were done in a radon-prone area in the Ardennes (Belgium). The surface activity of several glass sheets was measured using detectors that were fixed on indoor glass surfaces. Simultaneously the indoor radon concentration was measured using diffusion chambers. By using Monte Carlo techniques, it could be proven that there is a discrepancy between this data set and the room model calculations, which are normally used to correlate surface activity and past radon exposure. To solve this, a modification of the model is proposed.

  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. Radiation doses to individuals due to ²³⁸U, ²³²Th and ²²²Rn from the immersion in thermal waters and to radon progeny from the inhalation of air inside thermal stations.

    PubMed

    Misdaq, M A; Ghilane, M; Ouguidi, J; Outeqablit, K

    2012-11-01

    In Morocco, thermal waters have been used for decades for the treatment of various diseases. To explore the exposure pathway of (238)U, (232)Th and (222)Rn to the skin of bathers from the immersion in thermal waters, these radionuclides were measured inside waters collected from different Moroccan thermal springs, by means of CR-39 and LR-115 type II solid-state nuclear track detectors (SSNTDs), and corresponding annual committed effective doses to skin were determined. Accordingly, to assess radiation dose due to radon short-lived decay products from the inhalation of air by individuals, concentrations of these radionuclides were measured in indoor air of two thermal stations by evaluating mean critical angles of etching of the CR-39 and LR-115 II SSNTDs. Committed effective doses due to the short-lived radon decay products (218)Po and (214)Po by bathers and working personnel inside the thermal stations studied were determined.

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

    SciTech Connect

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

    1984-04-01

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

  18. 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.

  19. Thoron and thoron progeny measurements in German clay houses.

    PubMed

    Gierl, S; Meisenberg, O; Feistenauer, P; Tschiersch, J

    2014-07-01

    In recent years, elevated thoron concentrations were found in houses built of unfired clay. In this study experiments were carried out in 17 traditional and modern clay houses in Germany to obtain an overview of indoor thoron in such houses. Long-term measurements over an 8-week period were performed using a newly developed Unattended Battery-Operated Progeny Measurement Device (UBPM) for measuring thoron progeny. This instrument uses a high-voltage electric field to precipitate radon and thoron progeny on nuclear track detectors. Additional active and passive measurements of radon, thoron and their progeny were performed. The equilibrium equivalent thoron concentration was found to be between 2 and 10 Bq m(-3). Gas concentrations were found to be between 20 and 160 Bq m(-3) for radon and between 10 and 90 Bq m(-3) for thoron 20 cm from the wall. The thoron exposure contributes significantly to the inhalation dose of the dwellers (0.6-4 mSv a(-1)).

  20. Measurements of radon concentrations in the lunar atmosphere

    NASA Technical Reports Server (NTRS)

    Brodzinski, R. L.; Jackson, P. O.; Langford, J. C.

    1977-01-01

    The radon concentrations in the lunar atmosphere were determined by measuring the Po-210 progeny activity in artifacts returned from the moon. Experiments performed on a section of the polished aluminum strut from Surveyor 3 and data obtained from the Apollo 16 Cosmic Ray Detector Experiment Teflon thermal shield are compared with other values of the lunar radon concentration obtained at different times and different locations and by various techniques. Possible sources and release mechanisms compatible with all of the data are discussed. An experimental procedure to determine the relative retention coefficients of various types of material for radon progeny in a simulated lunar environment is described. The results of several experiments are given, and their effect on lunar radon progeny measurements is discussed. An analytical procedure is given for the analysis of a Teflon matrix for trace constituents.

  1. Measurements of radon around closed uranium mines.

    PubMed

    Furuta, Sadaaki; Ito, Kimio; Ishimori, Yuu

    2002-01-01

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

  2. Radon in outdoor air in Nevada.

    PubMed

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

    1994-04-01

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

  3. 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.

  4. In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

    SciTech Connect

    Guilmette, R.A.; Laurer, G.R.; Lambert, W.E.; Gilliland, F.D.

    1995-12-01

    It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne {sup 222}Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee`s work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of {sup 210}Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of {sup 210}Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring {sup 210}Pb in the heads of former uranium miners has been accomplished.

  5. 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.

  6. 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

  7. 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.

  8. Problems with Estimating Annual Mean Indoor Radon Concentrations

    NASA Astrophysics Data System (ADS)

    Marušiaková, Miriam; Hůlka, Jińrí

    2010-09-01

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

  9. Problems with Estimating Annual Mean Indoor Radon Concentrations

    SciTech Connect

    Marusiakova, Miriam; Hulka, Jiri

    2010-09-30

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

  10. A study of factors affecting indoor radon properties.

    PubMed

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

    1996-08-01

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

  11. A study of factors affecting indoor radon properties

    SciTech Connect

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

    1996-08-01

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

  12. Assessment of lifetime lung cancer risks induced by environmental radon

    SciTech Connect

    Mei, G.T.; Schutz, D.F.

    1987-01-01

    Radon and its progeny in air (/sup 218/Po, /sup 214/Pb, /sup 214/Bi, and /sup 214/Po) may enter the human body by inhalation and cause radiation damage to the respiratory tract to induce lung cancer. Among uranium miners, lung cancer induced by long term exposure to elevated levels of radon progeny is well established. The epidemiological evidence provided by such miners is the principal basis for determining the numerical relationship between environmental levels of radon exposure and lung cancer incidence. A number of lung cancer risk models have been published. All of these models are based on an intensity of radon or radon progeny exposure, referring to an average exposure over time, and on an assumed percentage of occupancy. However, the differences in life-styles among individuals or the seasonal variation in radon levels found in a home, which may influence the level of radon exposure, have not been considered in the published risk models. An assessment of the possible lifetime lung cancer risk from exposure to environmental levels of radon is presented.

  13. 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

  14. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha, India.

    PubMed

    Ramola, R C; Gusain, G S; Rautela, B S; Sagar, D V; Prasad, G; Shahoo, S K; Ishikawa, T; Omori, Y; Janik, M; Sorimachi, A; Tokonami, S

    2012-11-01

    Exposure to radon, (222)Rn, is assumed to be the most significant source of natural radiation to human beings in most cases. It is thought that radon and its progeny are major factors that cause cancer. The presence of thoron, (220)Rn, was often neglected because it was considered that the quantity of thoron in the environment is less than that of radon. However, recent studies have shown that a high thoron concentration was found in some regions and the exposure to (220)Rn and its progeny can equal or several time exceed that of (220)Rn and its progeny. The results of thoron and its progeny measurements in the houses of high background radiation area (HBRA) of the southeastern coast of Odisha, India presented here. This area is one of the high background radiation areas in India with a large deposit of monazite sand which is the probable source of thoron. Both active and passive methods were employed for the measurement of thoron and its progeny in cement, brick and mud houses in the study area. Thoron concentration was measured using RAD-7 and Raduet. A CR-39 track detector was employed for the measurement of environmental thoron progeny, both in active and passive modes. Thoron and its progeny concentrations were found to be comparatively high in the area. A comparison between the results obtained with various techniques is presented in this paper.

  15. 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

  16. 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.

  17. 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

  18. Review of radon and lung cancer risk

    SciTech Connect

    Samet, J.M.; Hornung, R.W. )

    1990-03-01

    Radon, a long-established cause of lung cancer in uranium and other underground miners, has recently emerged as a potentially important cause of lung cancer in the general population. The evidence for widespread exposure of the population to radon and the well-documented excess of lung cancer among underground miners exposed to radon decay products have raised concern that exposure to radon progeny might also be a cause of lung cancer in the general population. To date, epidemiological data on the lung cancer risk associated with environmental exposure to radon have been limited. Consequently, the lung cancer hazard posed by radon exposure in indoor air has been addressed primarily through risk estimation procedures. The quantitative risks of lung cancer have been estimated using exposure-response relations derived from the epidemiological investigations of uranium and other underground miners. We review five of the more informative studies of miners and recent risk projection models for excess lung cancer associated with radon. The principal models differ substantially in their underlying assumptions and consequently in the resulting risk projections. The resulting diversity illustrates the substantial uncertainty that remains concerning the most appropriate model of the temporal pattern of radon-related lung cancer. Animal experiments, further follow-up of the miner cohorts, and well-designed epidemiological studies of indoor exposure should reduce this uncertainty. 18 references.

  19. Acute Exposure from RADON-222 and Aerosols in Drinking Water

    NASA Astrophysics Data System (ADS)

    Bernhardt, George Paul, IV

    Radon-222 in water is released when the water is aerated, such as during showering. As a result, a temporary burst of radon-222 can appear as a short term, or acute, exposure. This study looked at homes with radon-222 concentrations in water from 800 picocuries per liter (pCi/l) to 53,000 pCi/l to determine the buildup of radon gas in a bathroom during showering. Samples from the tap and drain, compared to determine the percentage of radon-222 released, showed that between 58% and 88% of radon-222 in the water was released. The resultant radon-222 increase in air, measured with a flow-through detector, ranged from 2 pCi/l to 114 pCi/l in bathrooms due to a 10 to 15 minute shower with water flow rates ranging from 3 l/min to 6 l/min. Significantly, these rates did not fall rapidly but stayed approximately the same for up to 15 minutes after the water flow ceased. In examining exposures, the true danger is in the radon-222 progeny rather than the radon itself. The progeny can be inhaled and deposited in the tracheobronchial passages in the lung. Filter samples of bathroom air measured in a portable alpha spectrometer showed an increase in radon-222 progeny, notably polonium-218 and -214, in the air after showering. These increases were gradual and were on the order of 0.5 pCi/l at the highest level. Tap samples measured in a portable liquid scintillator showed that the progeny are present in the water but are not in true secular equilibrium with the radon-222 in the water. Therefore, the radon-222 does not have to decay to produce progeny since the progeny are already present in the water. A two stage sampler was used to examine the percentage of radiation available in aerosols smaller than 7 microns. Repeated trials showed that up to 85% of the radiation available in the aerosols is contained in the smaller, more respirable particles.

  20. 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)

  1. Passive Measurements of Thoron and its Progeny in some Dwellings in Ireland

    SciTech Connect

    Choncubhair, Orlaith Ni; Laughlin, James Mc; Tokonami, Shinji

    2008-08-07

    In this paper, an account is given of the development, calibration and field use of a passive alpha track detector sensitive to thoron as well as to radon. No database of thoron and thoron progeny concentrations in dwellings in Ireland exists and, as a result, the level of exposure of the Irish population to thoron and its progeny is unknown. As an initial or pilot stage in establishing such a data base measurements of thoron and thoron progeny concentrations (the latter expressed in Equilibrium Equivalent Thoron Concentration (EETC)) were made in 40 randomly chosen Irish dwellings. The EETC measurements were made using a passive thoron progeny deposition rate monitor designed and supplied by NIRS (Japan). In addition standard unmodified SSI passive radon detectors were used to measure radon in these dwellings. The measured thoron concentrations ranged from below the level of detection to 154 Bq/m{sup 3} while the radon gas ranged from 15 to 179 Bq/m{sup 3}. The thoron progeny EETC values for these dwellings ranged from 0.03 to 7.7 Bq/m{sup 3}. An account is also given of the dosimetric implications of these measurements.

  2. Anucleate platelets generate progeny

    PubMed Central

    Schwertz, Hansjörg; Köster, Sarah; Kahr, Walter H. A.; Michetti, Noemi; Kraemer, Bjoern F.; Weitz, David A.; Blaylock, Robert C.; Kraiss, Larry W.; Greinacher, Andreas; Zimmerman, Guy A.

    2010-01-01

    Platelets are classified as terminally differentiated cells that are incapable of cellular division. However, we observe that anucleate human platelets, either maintained in suspension culture or captured in microdrops, give rise to new cell bodies packed with respiring mitochondria and α-granules. Platelet progeny formation also occurs in whole blood cultures. Newly formed platelets are structurally indistinguishable from normal platelets, are able to adhere and spread on extracellular matrix, and display normal signal-dependent expression of surface P-selectin and annexin V. Platelet progeny formation is accompanied by increases in biomass, cellular protein levels, and protein synthesis in expanding populations. Platelet numbers also increase during ex vivo storage. These observations indicate that platelets have a previously unrecognized capacity for producing functional progeny, which involves a form of cell division that does not require a nucleus. Because this new function of platelets occurs outside of the bone marrow milieu, it raises the possibility that thrombopoiesis continues in the bloodstream. PMID:20086251

  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. Residential Radon Appears to Prevent Lung Cancer

    PubMed Central

    Scott, Bobby R.

    2011-01-01

    Residential radon has been found to be associated with lung cancer in epidemiological/ecological studies and the researchers have inappropriately concluded that residential radon causes lung cancer. Their conclusion relates to the linear-no-threshold (LNT) hypothesis-based, risk-assessment paradigm; however, the LNT hypothesis has been invalidated in numerous studies. It is shown in this paper that our hormetic relative risk (HRR) model is consistent with lung cancer data where detailed measurements of radon in each home were carried out. Based on the HRR model, low-level radon radioactive progeny is credited for activated natural protection (ANP) against lung cancer including smoking-related lung cancer. The proportion B(x) (benefit function) of ANP beneficiaries increases as the average radon level x increases to near the Environmental Protection Agency’s action level of 4 picocuries/L (approximately 150 Bq m−3). As the average level of radon increases to somewhat above the action level, ANP beneficiaries progressively decrease to zero (B(x) decreases to 0), facilitating the occurrence of smoking-related lung cancers as well as those related to other less important risk factors. Thus, residential radon does not appear to cause lung cancer but rather to protect, in an exposure-level-dependent manner, from its induction by other agents (e.g., cigarette-smoke-related carcinogens). PMID:22461755

  5. RADON EXPOSURE ASSESSMENT AND DOSIMETRY APPLIED TO EPIDEMIOLOGY AND RISK ESTIMATION

    EPA Science Inventory

    Epidemiological studies of underground miners provide the primary basis for radon risk estimates for indoor exposures as well as mine exposures. A major source of uncertainty in these risk estimates is the uncertainty in radon progeny exposure estimates for the miners. In addit...

  6. Influence of air flow on the behavior of thoron and its progeny in a traditional Japanese house

    SciTech Connect

    Ma, Jizeng; Doi, Masahiro; Kobayashi, Sadayoshi

    1997-01-01

    Air flow influence on the spatial distribution of thoron ({sup 220}Rn) concentration in a typical Japanese traditional house was investigated at various indoor air flow levels. The effect of air flow on the behavior of both thoron and radon progeny were examined simultaneously. Measurements were carried out by using two types of passive monitors, the radon-thoron discriminative monitor and the Radtrak monitor. Thoron and radon progeny were measured by filter grab sampling with ZnS scintillation counting. Under static condition, a horizontal distribution with greatly varied thoron concentrations was found as reported by previous studies. Under turbulent conditions, thoron concentrations in the middle of the room increased and the concentration gradient of thoron gas became lower. An obvious vertical distribution of thoron was also observed. Prominent diurnal variation of radon progeny concentrations was observed whereas that of thoron progeny concentrations was not. Concentration of thoron progeny changed little at different air flow levels, although the thoron gas level at the middle of the room varied significantly. The influence of air flows on detection efficiencies of the two types of thoron monitors were also checked. The mechanism of behavioral change of thoron and its progeny in turbulent atmosphere is discussed. 18 refs., 7 figs.

  7. Cigarette use and the estimation of lung cancer attributable to radon in the United States

    SciTech Connect

    Lubin, J.H.; Steindorf, K. |

    1995-01-01

    Residential exposure to radioactive radon and its decay products has been estimated to account for 10-12% of all lung cancer deaths in the US. It has been difficult to evaluate fully the impact of cigarette smoking, the most important cause of lung cancer, on this estimate, because factors for patterns of tobacco use have not been included in the risk models, since risk models are derived from studies of underground miners exposed to radon and detailed data on smoking are limited. Lung cancer risk estimates for exposure to radon progeny in smoker and non-smoker populations are obtained by applying the same risk model to each population group, thereby assuming the joint effects of smoking and exposure to radon progeny are multiplicative. However, in miners, joint relative risks (RR) for the two exposures are most consistent with an intermediate relationship between multiplicative and additive, so that the present approach likely results in an overestimate of risk in smokers and an underestimate of risk in nonsmokers. One approach for adjusting risk models to incorporate smoking status is based on the relative magnitude of the effects of radon progeny in smokers and nonsmokers and therefore may not be applicable to non-miner populations if the proportion of smokers and the RR for smoking differ. We show that the modification can be derived explicitly by assuming an arithmetic mixture model for the joint RR for smoking and exposure to radon progeny. In this way, smoking parameters in the population of interest (the proportion of smokers and the RR of smoking) can be used directly to adjust radon progeny risk models and obtain risk estimates that are specific for smokers and nonsmokers. With an intermediate RR relationship for smoking and radon progeny, the attributable percentage of lung cancer deaths from residential radon may be twofold greater in nonsmokers than in smokers. 20 refs., 1 fig., 3 tabs.

  8. 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.

  9. 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.

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

    PubMed

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

    2011-03-01

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

  11. Variability of radon and thoron equilibrium factors in indoor environment of Garhwal Himalaya.

    PubMed

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Kandari, Tushar; Gusain, G S; Mishra, Rosaline; Ramola, R C

    2016-01-01

    The measurements of radon, thoron and their progeny concentrations have been carried out in the dwellings of Uttarkashi and Tehri districts of Garhwal Himalaya, India using LR-115 detector based pin-hole dosimeter and DRPS/DTPS techniques. The equilibrium factors for radon, thoron and their progeny were calculated by using the values measured with these techniques. The average values of equilibrium factor between radon and its progeny have been found to be 0.44, 0.39, 0.39 and 0.28 for rainy, autumn, winter and summer seasons, respectively. For thoron and its progeny, the average values of equilibrium factor have been found to be 0.04, 0.04, 0.04 and 0.03 for rainy, autumn, winter and summer seasons, respectively. The equilibrium factor between radon and its progeny has been found to be dependent on the seasonal changes. However, the equilibrium factor for thoron and progeny has been found to be same for rainy, autumn and winter seasons but slightly different for summer season. The annual average equilibrium factors for radon and thoron have been found to vary from 0.23 to 0.80 with an average of 0.42 and from 0.01 to 0.29 with an average of 0.07, respectively. The detailed discussion of the measurement techniques and the explanation for the results obtained is given in the paper. PMID:26520684

  12. Variability of radon and thoron equilibrium factors in indoor environment of Garhwal Himalaya.

    PubMed

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Kandari, Tushar; Gusain, G S; Mishra, Rosaline; Ramola, R C

    2016-01-01

    The measurements of radon, thoron and their progeny concentrations have been carried out in the dwellings of Uttarkashi and Tehri districts of Garhwal Himalaya, India using LR-115 detector based pin-hole dosimeter and DRPS/DTPS techniques. The equilibrium factors for radon, thoron and their progeny were calculated by using the values measured with these techniques. The average values of equilibrium factor between radon and its progeny have been found to be 0.44, 0.39, 0.39 and 0.28 for rainy, autumn, winter and summer seasons, respectively. For thoron and its progeny, the average values of equilibrium factor have been found to be 0.04, 0.04, 0.04 and 0.03 for rainy, autumn, winter and summer seasons, respectively. The equilibrium factor between radon and its progeny has been found to be dependent on the seasonal changes. However, the equilibrium factor for thoron and progeny has been found to be same for rainy, autumn and winter seasons but slightly different for summer season. The annual average equilibrium factors for radon and thoron have been found to vary from 0.23 to 0.80 with an average of 0.42 and from 0.01 to 0.29 with an average of 0.07, respectively. The detailed discussion of the measurement techniques and the explanation for the results obtained is given in the paper.

  13. Personal radon dosimetry from eyeglass lenses.

    PubMed

    Fleischer, R L; Meyer, N R; Hadley, S A; MacDonald, J; Cavallo, A

    2001-01-01

    Eyeglass lenses are commonly composed of allyl-diglycol carbonate (CR-39), an alpha-particle detecting plastic, thus making such lenses personal radon dosemeters. Samples of such lenses have been obtained, etched to reveal that radon and radon progeny alpha tracks can be seen in abundance, and sensitivities have been calibrated in radon chambers as a primary calibration, and with a uranium-based source of alpha particles as a convenient secondary standard. With one exception natural, environmental (fossil) track densities ranged from less than 3,000 to nearly 70,000 per cm2 for eyeglasses that had been worn for various times from one to nearly five years. Average radon concentrations to which those wearers were exposed are inferred to be in the range 14 to 130 Bq x m(-3) (0.4 to 3.5 pCi x l(-1)). A protocol for consistent, meaningful readout is derived and used. In the exceptional case the fossil track density was 1,780,000 cm(-2) and the inferred (24 h) average radon concentration was 6500 Bq x m(-3) (175 pCi x l(-1)) for a worker at an inactive uranium mine that is used for therapy.

  14. 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.

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

    SciTech Connect

    Mehta, Vimal; Singh, Tejinder Pal; Chauhan, R. P.; Mudahar, G. S.

    2015-08-28

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

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

    NASA Astrophysics Data System (ADS)

    Mehta, Vimal; Singh, Tejinder Pal; Chauhan, R. P.; Mudahar, G. S.

    2015-08-01

    Radon and its progeny are major contributors in the radiation dose received by general population of the world. Because radon is a noble gas, a large portion of it is free to migrate away from radium. The primary sources of radon in the houses are soils and rocks source emanations, emanation from building materials, and entry of radon into a structure from outdoor air. Keeping this in mind the study of radon exhalation rate from some soil samples of the Kharar, Punjab has been carried out using Can Technique. The equilibrium radon concentration in various soil samples of Kharar area of district Mohali varied from 12.7 Bqm-3 to 82.9 Bqm-3 with an average of 37.5 ± 27.0 Bqm-3. The radon mass exhalation rates from the soil samples varied from 0.45 to 2.9 mBq/kg/h with an average of 1.4 ± 0.9 mBq/kg/h and radon surface exhalation rates varied from 10.4 to 67.2 mBq/m2/h with an average of 30.6 ± 21.8 mBq/m2/h. The radon mass and surface exhalation rates of the soil samples of Kharar, Punjab were lower than that of the world wide average.

  17. 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

  18. 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.

  19. 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.

  20. 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)

  1. 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)

  2. H. R. 5138: This Act may be cited as the Radon Measurement Proficiency Act. Introduced in the House of Representatives, One Hundred First Congress, Second Session, June 21, 1990

    SciTech Connect

    Not Available

    1990-01-01

    A bill was introduced in the U.S. House of Representatives to direct the Administrator of the U.S. Environmental Protection Agency to conduct radon measurement proficiency research and to establish a mandatory radon measurement proficiency program. The purpose of the research will be to assess the ability of measuring methods and protocols to accurately assess exposure to radon progeny.

  3. 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

  4. Study of radon concentrations in oil refinery premises and city dwellings.

    PubMed

    Singh, A K; Khan, A J; Prasad, R

    2001-06-01

    Radon and its progeny concentrations were measured in several dwellings at an oil refinery premises and these concentrations were compared with those found in dwellings in Mathura and Agra cities. Radon progeny concentrations were measured using LR-115 type II nuclear track etch detectors. The radon concentrations were estimated by using a value of 0.42 for the equilibrium factor. The geometric means (GM) of radon concentrations in the refinery dwellings, Mathura city and Agra city dwellings were 97, 91 and 75 Bq m(-3) with geometric standard deviations of 1.7, 1.8 and 1.8 respectively. The average lifetime risk of lung cancer for an adjusted annual average chronic radon exposure of 69 Bq m(-3) (7.8 mWL; WL = working level) with an occupancy factor of 0.7 comes out to be 5.4 x 10(-3).

  5. A survey of radon properties in underground shopping centers in Hong Kong.

    PubMed

    Yu, K N; Young, E C; Stokes, M J; Lo, C H

    1997-06-01

    A number of radon-related properties have been surveyed in underground shopping centers in Hong Kong. These parameters include the radon concentration, the total potential alpha energy concentration of radon progeny, the equilibrium factor and the unattached fraction of radon progeny. The mean values recorded for these were 29.2 +/- 7.8 Bq/m3, 3.60 +/- 1.53 mWL, 0.46 +/- 0.16 and 0.05 +/- 0.03, respectively. Based on these figures, we have calculated the average radon dose received by employees in an underground shopping center in Hong Kong to be 0.22 mSv/yr, which represents an approximate increase of 8% over the total dose of about 2.7 mSv/yr received by the average person in Hong Kong.

  6. 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.

  7. 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

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

    PubMed

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

    2012-11-01

    The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya, India was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq l(-1) with a mean of 50 Bq l(-1) in groundwater in different lithotectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks.

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

    PubMed

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

    2012-11-01

    The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya, India was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq l(-1) with a mean of 50 Bq l(-1) in groundwater in different lithotectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks. PMID:22914330

  10. Activation of oncogenes by radon progeny and x-rays

    SciTech Connect

    Ling, C.C.

    1990-01-01

    The overall goal of this proposal is to study the carcinogenic effect of both high and low LET radiation at the molecular level, utilizing techniques developed in molecular biology, cancer cell biology and radiation biology. The underlying assumption is that malignant transformation of normal cells is a multistep process requiring two or more molecular events in the genomic DNA. We hypothesize that radiation may induce such events in one or more steps of the multistep process. We will use in vitro models of transformation that reproduce the stepwise progression of normal cells toward the transformed phenotype and ask whether radiation can provide the necessary activating function at discrete steps along this path. Our strategy involves transfecting into normal primary cells a variety of cloned oncogenes that are known to supply only some of the functions necessary for full transformation. These partially transformed'' cells will be the targets for irradiation by x-rays and alpha particles. The results will provide the basis for assessing the ability of ionizing radiation to activate oncogenic functions that complement'' the oncogene already present in the transfected cells and produce the fully transformed phenotype. Progress is described. 121 refs.

  11. Optical image sensors and their application in radon detection

    NASA Astrophysics Data System (ADS)

    Griffin, Ryan H.; Tarr, N. Garry

    2013-10-01

    This paper reports on the development and testing of a direct reading radon detector assembled from consumer electronics at very low cost. An electrostatic concentrator constructed by metalizing a plastic funnel is used to focus charged radon progeny onto the exposed surface of an optical image sensor from a webcam. Alpha particles emitted by the collected progeny strike the image sensor, generating sufficient charge to completely saturate one or more pixels The high voltage required by the concentrator is generated using a simple Cockcroft-Walton charge pump. A personal computer is used to analyze the webcam data. Alpha particles were counted at a rate of 5.2 counts/ hour at a radon concentration of 159 Bq/ m3.

  12. 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%.

  13. 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

  14. 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.

  15. Absorbed doses of lungs from radon retained in airway lumens of mice and rats.

    PubMed

    Sakoda, Akihiro; Ishimori, Yuu; Yamaoka, Kiyonori; Kataoka, Takahiro; Mitsunobu, Fumihiro

    2013-08-01

    This paper provides absorbed doses arising from radon gas in air retained in lung airway lumens. Because radon gas exposure experiments often use small animals, the calculation was performed for mice and rats. For reference, the corresponding computations were also done for humans. Assuming that radon concentration in airway lumens is the same as that in the environment, its progeny's production in and clearance from airways were simulated. Absorbed dose rates were obtained for three lung regions and the whole lung, considering that secretory and basal cells are sensitive to radiation. The results showed that absorbed dose rates for all lung regions and whole lung generally increase from mice to rats to humans. For example, the dose rates for the whole lung were 25.4 in mice, 41.7 in rats, and 59.9 pGy (Bq m⁻³)⁻¹ h⁻¹ in humans. Furthermore, these values were also compared with lung dose rates from two other types of exposures, that is, due to inhalation of radon or its progeny, which were already reported. It was confirmed that the direct inhalation of radon progeny in the natural environment, which is known as a cause of lung cancer, results in the highest dose rates for all species. Based on the present calculations, absorbed dose rates of the whole lung from radon gas were lower by a factor of about 550 (mice), 200 (rats), or 70 (humans) than those from radon progeny inhalation. The calculated dose rate values are comparatively small. Nevertheless, the present study is considered to contribute to our understanding of doses from inhalation of radon and its progeny.

  16. 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.

  17. 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.

  18. Environmental Assessment for moving the Pacific Northwest Laboratory radon generators from Life Sciences Laboratory II, Richland North Area, to Life Sciences Laboratory I, 300 Area, and their continued use in physical and biological research

    SciTech Connect

    Nelson, I.C.

    1993-09-01

    The Pacific Northwest Laboratory (PNL) radon generators are a core resource of the overall U. S. Department of Energy`s (DOE) Radon Research Program and are administratively controlled within the ``Radon Hazards in Homes`` project. This project primarily focuses on radon exposures of animals and addresses the major biologic effects and factors influencing risks of indoor radon exposures. For example, the ``Mechanisms of Radon Injury`` and ``In vivo/In vitro Radon-Induced Cellular Damage`` projects specifically address the cytogenetic and DNA damage produced by radon exposure as part of a larger effort to understand radon carcinogenesis. Several other ongoing PNL projects, namely: ``Biological Effectiveness of Radon Alpha Particles: A Microbeam Study of Dose Rate Effects,`` ``Laser Measurements of Pb-210,`` ``Radon Transport Modeling in Soils,`` ``Oncogenes in Radiation Carcinogenesis,`` ``Mutation of DNA Targets,`` ``Dosimetry of Radon Progeny,`` and ``Aerosol Technology Development`` also use the radon exposure facilities in the conduct of their work. While most, but not all, studies in the PNL Radon Research Program are funded through DOE`s Office of Health and Environmental Research, PNL also has ongoing collaborative radon studies with investigators worldwide; many of these use the radon exposure facilities. The purpose of the proposed action is to provide for relocation of the radon generators to a DOE-owned facility and to continue to provide a controlled source of radon-222 for continued use in physical and biological research.

  19. A generic biokinetic model for noble gases with application to radon

    SciTech Connect

    Leggett, Richard Wayne; Marsh, James; Gregoratto, Demetrio; Blanchardon, Eric

    2013-01-01

    The International Commission for Radiological Protection (ICRP) currently uses a dose conversion coefficient to calculate effective dose per unit exposure to radon and its progeny. The coefficient is derived by dividing the detriment associated with unit exposure to radon, as estimated from epidemiological studies, by the detriment per unit effective dose, as estimated mainly from atomic bomb survivor data and animal studies. In a recent statement the ICRP indicated that future guidance on exposure to radon and its progeny will be developed in the same way as guidance for any other radionuclide. That is, intake of radon and progeny will be limited on the basis of effective dose coefficients derived from biokinetic and dosimetric models. This paper proposes a biokinetic model for systemic (absorbed) radon for use in the calculation of dose coefficients for inhaled or ingested radon. The model is based largely on physical laws governing transfer of a non-reactive and soluble gas between materials. Model predictions are shown to be consistent with results of controlled studies of the fate of internally deposited radon in human subjects.

  20. 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.

  1. Evaluation of the intake of radon through skin from thermal water

    PubMed Central

    Sakoda, Akihiro; Ishimori, Yuu; Tschiersch, Jochen

    2016-01-01

    The biokinetics of radon in the body has previously been studied with the assumption that its absorption through the skin is negligibly small. This assumption would be acceptable except in specific situations, such as bathing in a radon hot spring where the radon concentration in thermal water is far higher than that in air. The present study focused on such a situation in order to better understand the biokinetics of radon. To mathematically express the entry of radon through the skin into the body, we first modified the latest sophisticated biokinetic model for noble gases. Values of an important parameter for the model—the skin permeability coefficient K (m s−1)—were derived using data from previous human studies. The analysis of such empirical data, which corresponded to radon concentrations in the air exhaled by subjects during and following bathing in radon-rich thermal water, revealed that the estimated K values had a log-normal distribution. The validity of the K values and the characteristics of the present model are then discussed. Furthermore, the impact of the intake of radon or its progeny via inhalation or skin absorption on radiation dose was also assessed for possible exposure scenarios in a radon hot spring. It was concluded that, depending on the radon concentration in thermal water, there might be situations in which the dose contribution resulting from skin absorption of radon is comparable to that resulting from inhalation of radon and its progeny. This conclusion can also apply to other therapeutic situations (e.g. staying in the pool for a longer period). PMID:26983980

  2. Evaluation of the intake of radon through skin from thermal water.

    PubMed

    Sakoda, Akihiro; Ishimori, Yuu; Tschiersch, Jochen

    2016-07-01

    The biokinetics of radon in the body has previously been studied with the assumption that its absorption through the skin is negligibly small. This assumption would be acceptable except in specific situations, such as bathing in a radon hot spring where the radon concentration in thermal water is far higher than that in air. The present study focused on such a situation in order to better understand the biokinetics of radon. To mathematically express the entry of radon through the skin into the body, we first modified the latest sophisticated biokinetic model for noble gases. Values of an important parameter for the model-the skin permeability coefficient K (m s(-1))-were derived using data from previous human studies. The analysis of such empirical data, which corresponded to radon concentrations in the air exhaled by subjects during and following bathing in radon-rich thermal water, revealed that the estimated K values had a log-normal distribution. The validity of the K values and the characteristics of the present model are then discussed. Furthermore, the impact of the intake of radon or its progeny via inhalation or skin absorption on radiation dose was also assessed for possible exposure scenarios in a radon hot spring. It was concluded that, depending on the radon concentration in thermal water, there might be situations in which the dose contribution resulting from skin absorption of radon is comparable to that resulting from inhalation of radon and its progeny. This conclusion can also apply to other therapeutic situations (e.g. staying in the pool for a longer period). PMID:26983980

  3. 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.

  4. Activity of radon (222Rn) in the lower atmospheric surface layer of a typical rural site in south India

    NASA Astrophysics Data System (ADS)

    Kumar, K. Charan; Prasad, T. Rajendra; Ratnam, M. Venkat; Nagaraja, Kamsali

    2016-09-01

    Analysis of one year measurements of in situ radon (222Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth's surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5∘N and 79.2∘E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon in relation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence of rocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon (R = - 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be 12.01±0.66 Bq m-3 and 4.25±0.18 Bq m-3 for its progenies, in the study period.

  5. Radon dose assessment in underground mines in Brazil.

    PubMed

    Santos, T O; Rocha, Z; Cruz, P; Gouvea, V A; Siqueira, J B; Oliveira, A H

    2014-07-01

    Underground miners are internally exposed to radon, thoron and their short-lived decay products during the mineral processing. There is also an external exposure due to the gamma emitters present in the rock and dust of the mine. However, the short-lived radon decay products are recognised as the main radiation health risk. When inhaled, they are deposited in the respiratory system and may cause lung cancer. To address this concern, concentration measurements of radon and its progeny were performed, the equilibrium factor was determined and the effective dose received was estimated in six Brazilian underground mines. The radon concentration was measured by using E-PERM, AlphaGUARD and CR-39 detectors. The radon progeny was determined by using DOSEman. The annual effective dose for the miners was estimated according to United Nations Scientific Committee on the Effects of Atomic Radiation methodologies. The mean value of the equilibrium factor was 0.4. The workers' estimated effective dose ranged from 1 to 21 mSv a(-1) (mean 9 mSv a(-1)).

  6. Radon dose assessment in underground mines in Brazil.

    PubMed

    Santos, T O; Rocha, Z; Cruz, P; Gouvea, V A; Siqueira, J B; Oliveira, A H

    2014-07-01

    Underground miners are internally exposed to radon, thoron and their short-lived decay products during the mineral processing. There is also an external exposure due to the gamma emitters present in the rock and dust of the mine. However, the short-lived radon decay products are recognised as the main radiation health risk. When inhaled, they are deposited in the respiratory system and may cause lung cancer. To address this concern, concentration measurements of radon and its progeny were performed, the equilibrium factor was determined and the effective dose received was estimated in six Brazilian underground mines. The radon concentration was measured by using E-PERM, AlphaGUARD and CR-39 detectors. The radon progeny was determined by using DOSEman. The annual effective dose for the miners was estimated according to United Nations Scientific Committee on the Effects of Atomic Radiation methodologies. The mean value of the equilibrium factor was 0.4. The workers' estimated effective dose ranged from 1 to 21 mSv a(-1) (mean 9 mSv a(-1)). PMID:24723186

  7. Portable apparatus for the measurement of environmental radon and thoron

    DOEpatents

    Negro, Vincent C.

    2001-01-01

    The radometer is a portable instrument for the measurement of the concentration of atmospheric radon/thoron in a test area. A constant velocity pump pulls the air from the outside at a constant flow rate. If the air is too moist, some or all of the sample is passed through a desiccant filter prior to encountering an electrostatic filter. The electrostatic filter prevents any charged particles from entering the sampling chamber. Once the sample has entered the chamber, the progeny of the decay of radon/thoron are collected on a detector and measured. The measured data is compiled by a computer and displayed.

  8. Residential radon exposure and lung cancer

    SciTech Connect

    Neuberger, J.S.

    1994-12-31

    Epidemiological studies of underground uranium and hard-rock miners, as well as animal experiments, indicate that the decay products of radon gas are a contributory cause of lung cancer. While one might expect that residential radon (progeny) exposure might be linked to an increase in lung cancer rates, sufficient evidence from residential studies is required to support this assumption. To date this evidence has not been definitive enough. There are differences in age, sex, dust exposure, and smoking between groups exposed in mines and in homes. A number of published studies have addressed this question; a number of studies are under way. The composite results from these studies may be useful in reducing the uncertainty. This paper summarizes and critiques results and discusses several methodological issues related to the studies.

  9. Calibration system for radon EEC measurements.

    PubMed

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

    2015-06-01

    The measurement of radon equivalent equilibrium concentration (EECRn) is very simple and quick technique for the estimation of radon progeny level in dwellings or working places. The most typical methods of EECRn measurements are alpha radiometry or alpha spectrometry. In such technique, the influence of alpha particle absorption in filters and filter effectiveness should be taken into account. In the authors' work, it is demonstrated that more precise and less complicated calibration of EECRn-measuring equipment can be conducted by the use of the gamma spectrometer as a reference measuring device. It was demonstrated that for this calibration technique systematic error does not exceed 3 %. The random error of (214)Bi activity measurements is in the range 3-6 %. In general, both these errors can be decreased. The measurements of EECRn by gamma spectrometry and improved alpha radiometry are in good agreement, but the systematic shift between average values can be observed. PMID:25979737

  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. Radon sources and associated risk in terms of exposure and dose.

    PubMed

    Vogiannis, Efstratios G; Nikolopoulos, Dimitrios

    2014-01-01

    Radon concerns the international scientific community from the early twentieth century, initially as radium emanation and nearly the second half of the century as a significant hazard to human health. The initial brilliant period of its use as medicine was followed by a period of intense concern for its health effects. Miners in Europe and later in the U.S were the primary target groups surveyed. Nowadays, there is a concrete evidence that radon and its progeny can cause lung cancer (1). Human activities may create or modify pathways increasing indoor radon concentration compared to outdoor background. These pathways can be controlled by preventive and corrective actions (2). Indoor radon and its short-lived progeny either attached on aerosol particles or free, compose an air mixture that carries a significant energy amount [Potential Alpha-Energy Concentration (PAEC)]. Prior research at that topic focused on the exposure on PAEC and the dose delivered by the human body or tissues. Special mention was made to the case of water workers due to inadequate data. Furthermore, radon risk assessment and relevant legislation for the dose delivered by man from radon and its progeny has been also reviewed.

  13. Radon Sources and Associated Risk in Terms of Exposure and Dose

    PubMed Central

    Vogiannis, Efstratios G.; Nikolopoulos, Dimitrios

    2015-01-01

    Radon concerns the international scientific community from the early twentieth century, initially as radium emanation and nearly the second half of the century as a significant hazard to human health. The initial brilliant period of its use as medicine was followed by a period of intense concern for its health effects. Miners in Europe and later in the U.S were the primary target groups surveyed. Nowadays, there is a concrete evidence that radon and its progeny can cause lung cancer (1). Human activities may create or modify pathways increasing indoor radon concentration compared to outdoor background. These pathways can be controlled by preventive and corrective actions (2). Indoor radon and its short-lived progeny either attached on aerosol particles or free, compose an air mixture that carries a significant energy amount [Potential Alpha-Energy Concentration (PAEC)]. Prior research at that topic focused on the exposure on PAEC and the dose delivered by the human body or tissues. Special mention was made to the case of water workers due to inadequate data. Furthermore, radon risk assessment and relevant legislation for the dose delivered by man from radon and its progeny has been also reviewed. PMID:25601905

  14. Radon sources and associated risk in terms of exposure and dose.

    PubMed

    Vogiannis, Efstratios G; Nikolopoulos, Dimitrios

    2014-01-01

    Radon concerns the international scientific community from the early twentieth century, initially as radium emanation and nearly the second half of the century as a significant hazard to human health. The initial brilliant period of its use as medicine was followed by a period of intense concern for its health effects. Miners in Europe and later in the U.S were the primary target groups surveyed. Nowadays, there is a concrete evidence that radon and its progeny can cause lung cancer (1). Human activities may create or modify pathways increasing indoor radon concentration compared to outdoor background. These pathways can be controlled by preventive and corrective actions (2). Indoor radon and its short-lived progeny either attached on aerosol particles or free, compose an air mixture that carries a significant energy amount [Potential Alpha-Energy Concentration (PAEC)]. Prior research at that topic focused on the exposure on PAEC and the dose delivered by the human body or tissues. Special mention was made to the case of water workers due to inadequate data. Furthermore, radon risk assessment and relevant legislation for the dose delivered by man from radon and its progeny has been also reviewed. PMID:25601905

  15. 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.

  16. 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.

  17. 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.

  18. Comparative risk assessment of residential radon exposures in two radon-prone areas, Stei (Romania) and Torrelodones (Spain).

    PubMed

    Sainz, Carlos; Dinu, Alexandra; Dicu, Tiberius; Szacsvai, Kinga; Cosma, Constantin; Quindós, Luis Santiago

    2009-07-15

    Radon and radon progeny are present indoors, in houses and others dwellings, representing the most important contribution to dose from natural sources of radiation. Most studies have demonstrated an increased risk of lung cancer at high concentration of radon for both smokers and nonsmokers. The work presents a comparative analysis of the radon exposure data in the two radon-prone areas, Stei, Transylvania, (Romania), in the near of old Romanian uranium mines and in the granitic area of Torrelodones town, Sierra de Guadarrama (Spain). Measurements of indoor radon were performed in 280 dwellings (Romania) and 91 dwellings (Spain) by using nuclear track detectors, CR 39. The highest value measured in Stei area was 2650 Bq m(-3) and 366 Bq m(-3) in the Spanish region. The results are computed with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bq m(-3). We used the EC Radon Software to calculate the lifetime lung cancer death risks for individuals groups in function of attained age, radon exposures and tobacco consumption. A total of 233 lung cancer deaths were observed in the Stei area for a period of 13 years (1994-2006), which is 116.82% higher than expected from the national statistics. In addition, the number of deaths estimated for the year 2005 is 28, which is worth more than 2.21 times the amount expected by authorities. In comparison, for Torrelodones was rated a number of 276 deaths caused by lung cancer for a period of 13 years, which is 2.09 times higher than the number expected by authorities. For the year 2005 in the Spanish region were reported 32 deaths caused by pulmonary cancer, the number of deaths exceeding seen again with a factor of 2.10 statistical expectations. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure.

  19. Comparative risk assessment of residential radon exposures in two radon-prone areas, Stei (Romania) and Torrelodones (Spain).

    PubMed

    Sainz, Carlos; Dinu, Alexandra; Dicu, Tiberius; Szacsvai, Kinga; Cosma, Constantin; Quindós, Luis Santiago

    2009-07-15

    Radon and radon progeny are present indoors, in houses and others dwellings, representing the most important contribution to dose from natural sources of radiation. Most studies have demonstrated an increased risk of lung cancer at high concentration of radon for both smokers and nonsmokers. The work presents a comparative analysis of the radon exposure data in the two radon-prone areas, Stei, Transylvania, (Romania), in the near of old Romanian uranium mines and in the granitic area of Torrelodones town, Sierra de Guadarrama (Spain). Measurements of indoor radon were performed in 280 dwellings (Romania) and 91 dwellings (Spain) by using nuclear track detectors, CR 39. The highest value measured in Stei area was 2650 Bq m(-3) and 366 Bq m(-3) in the Spanish region. The results are computed with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bq m(-3). We used the EC Radon Software to calculate the lifetime lung cancer death risks for individuals groups in function of attained age, radon exposures and tobacco consumption. A total of 233 lung cancer deaths were observed in the Stei area for a period of 13 years (1994-2006), which is 116.82% higher than expected from the national statistics. In addition, the number of deaths estimated for the year 2005 is 28, which is worth more than 2.21 times the amount expected by authorities. In comparison, for Torrelodones was rated a number of 276 deaths caused by lung cancer for a period of 13 years, which is 2.09 times higher than the number expected by authorities. For the year 2005 in the Spanish region were reported 32 deaths caused by pulmonary cancer, the number of deaths exceeding seen again with a factor of 2.10 statistical expectations. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure. PMID:19428051

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

    PubMed

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

    2016-01-01

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

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

    PubMed

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

    2016-01-01

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

  2. 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.

  3. 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

  4. Studies of indoor radon and lung cancer risk

    SciTech Connect

    Lubin, J.H.

    1997-03-01

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

  5. Radon action level for high-rise buildings

    SciTech Connect

    Leung, J.K.C.; Tso, M.Y.W.; Ho, C.W. . Radioisotope Unit)

    1999-05-01

    Radon and its progeny are the major contributors to the natural radiation dose received by human beings. Many countries and radiological authorities have recommended radon action levels to limit the indoor radon concentrations, and, hence, the annual doses to the general public. Since the sources of indoor radon and the methods for reducing its concentration are different for different types of buildings, social and economic factors have to be considered when setting the action level. But so far no action levels are specifically recommended for cities that have dwellings and offices all housed in high-rise buildings. In this study, an optimization approach was used to determine an action level for high-rise buildings based on data obtained through previous territory-wide radon surveys. A protection cost of HK $0.044 per unit fresh air change rate per unit volume and a detriment cost of HK $120,000 per person-Sv were used, which gave a minimum total cost at an action level of 200 Bq m[sup [minus]3]. The optimization analyses were repeated for different simulated radon distributions and living environment, which resulted in quite significantly different action levels. Finally, an action level of 200 Bq m[sup [minus]3] was recommended for existing buildings and 150 Bq m[sup [minus]3] for newly built buildings.

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

    PubMed

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

    2015-06-01

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

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

    PubMed

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

    2015-06-01

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

  8. 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.

  9. 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.

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

    PubMed Central

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

    2016-01-01

    Because 222Rn is a progeny of 238U, the relative abundance of uranium may be used to predict the areas that have the potential for high indoor radon concentration and therefore determine the best areas to conduct future surveys. Geographic Information System (GIS) mapping software was used to construct maps of South Dakota that included levels of uranium concentrations in soil and stream water and uranium deposits. Maps of existing populations and the types of land were also generated. Existing data about average indoor radon levels by county taken from a databank were included for consideration. Although the soil and stream data and existing recorded average indoor radon levels were sparse, it was determined that the most likely locations of elevated indoor radon would be in the northwest and southwest corners of the state. Indoor radon levels were only available for 9 out of 66 counties in South Dakota. This sparcity of data precluded a study of correlation of radon to geological features, but further motivates the need for more testing in the state. Only actual measurements should be used to determine levels of indoor radon because of the strong roles home construction and localized geology play in radon concentration. However, the data visualization method demonstrated here is potentially useful for directing resources relating to radon screening campaigns. PMID:26472478

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

    PubMed

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

    2016-01-01

    Because (222)Rn is a progeny of (238)U, the relative abundance of uranium may be used to predict the areas that have the potential for high indoor radon concentration and therefore determine the best areas to conduct future surveys. Geographic Information System (GIS) mapping software was used to construct maps of South Dakota that included levels of uranium concentrations in soil and stream water and uranium deposits. Maps of existing populations and the types of land were also generated. Existing data about average indoor radon levels by county taken from a databank were included for consideration. Although the soil and stream data and existing recorded average indoor radon levels were sparse, it was determined that the most likely locations of elevated indoor radon would be in the northwest and southwest corners of the state. Indoor radon levels were only available for 9 out of 66 counties in South Dakota. This sparcity of data precluded a study of correlation of radon to geological features, but further motivates the need for more testing in the state. Only actual measurements should be used to determine levels of indoor radon because of the strong roles home construction and localized geology play in radon concentration. However, the data visualization method demonstrated here is potentially useful for directing resources relating to radon screening campaigns. PMID:26472478

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

    PubMed

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

    2016-01-01

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

  13. Point-of-entry removal of radon from drinking water

    SciTech Connect

    Lowry, J.D.; Brutsaert, W.F.; Mc Enerney, T.; Molk, C.

    1987-04-01

    Two processes were investigated in the laboratory to determine their efficiency for removing radon from household water supplies. Granular activated carbon (GAC) adsorption was found to be extremely effective as a result of an adsorption-decay steady state that is established quickly and continues for years. The GAC bed, however, adsorbs radon progeny as the radon decays, and it becomes a source of gamma radiation. This problem is believed to be manageable for the vast majority of potential applications. Diffused bubble aeration was found to be as effective as GAC, with removals of greater than 99 percent being practical. Although more costly than GAC, aeration does not have the problem of gamma activity buildup.

  14. 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.

  15. 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)

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

    PubMed

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

    2016-09-01

    Radon activity concentrations (in water and in air) were measured at 13 selected locations at the Avalon Springs thermal spa resort in Montagu (Western Cape, South Africa) to estimate the associated effective dose received by employees and visitors. A RAD-7 detector (DURRIDGE), based on alpha spectrometry, and electret detectors (E-PERM®Radelec) were used for these radon measurements. The primary source of radon was natural thermal waters from the hot spring, which were pumped to various locations on the resort, and consequently a range of radon in-water analyses were performed. Radon in-water activity concentration as a function of time (short term and long term measurements) and spatial distributions (different bathing pools, etc.) were studied. The mean radon in-water activity concentrations were found to be 205 ± 6 Bq L (source), 112 ± 5 Bq L (outdoor pool) and 79 ± 4 Bq L (indoor pool). Radon in-air activity concentrations were found to range between 33 ± 4 Bq m (at the outside bar) to 523 ± 26 Bq m (building enclosing the hot spring's source). The most significant potential radiation exposure identified is that due to inhalation of air rich in radon and its progeny by the resort employees. The annual occupational effective dose due to the inhalation of radon progeny ranges from 0.16 ± 0.01 mSv to 0.40 ± 0.02 mSv. For the water samples collected, the Ra in-water activity concentrations from samples collected were below the lower detection limit (~0.7 Bq L) of the γ-ray detector system used. No significant radiological health risk can be associated with radon and progeny from the hot spring at the Avalon Springs resort. PMID:27472753

  17. 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)

  18. Radon level and radon effective dose rate determination using SSNTDs in Sannur cave, Eastern desert of Egypt.

    PubMed

    Amin, Rafat M; Eissa, M F

    2008-08-01

    For the assessment of inhalation doses due to radon and its progeny to cavern workers and visitors, it is necessary to have information on the time integrated gas concentrations and equilibrium factors. Passive single cup dosimeters using solid state nuclear track detectors (SSNTD) is the best suited for this purpose in wadi Sannur cave, Beni Suef, Egypt. The average radon concentration measurements for the cave are 836 +/- 150 Bq m(-3) by CR-39 detectors and for equilibrium factor an overall average of all measured values was used 0.687. The effective dose for cave workers is 3.65 mSv/year while for visitors is 23 muSv/year. Comparing these values to the Ionizing Radiation Regulations (IRR) values which indicate that the estimated effective doses for workers and visitors in this cave are less than the average overall radon dose.

  19. 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.

  20. Size distribution of radon decay products in the range 0.1-10 nm.

    PubMed

    Zhukovsky, Michael; Rogozina, Marina; Suponkina, Anna

    2014-07-01

    Information about the size distribution of radioactive aerosols in nanometre range is essential for the purposes of air contamination monitoring, dose assessment to respiratory tract and planning of protective measures. The diffusion battery, which allows capturing particles in the size range of 0.1-10 nm, has developed. Interpreting data obtained from diffusion battery is very complex. The method of expectation maximisation by Maher and Laird was chosen for indirect inversion data. The experiments were performed in the box with equivalent equilibrium concentration of radon in the range of 7000-10,000 Bq m(-3). The three modes of size distribution of radon decay products aerosols were obtained: activity median thermodynamic diameter (AMTD) 0.3, 1.5 and 5 nm. These modes can be identified as: AMTD 0.3 nm--atoms of radon progeny (218Po in general); AMTD 1.5 nm--clusters of radon progeny atoms and non-radioactive atoms in the atmosphere; AMTD 5 nm--particles formed by coagulation of previous mode clusters with existing aerosol particles or nucleation of condensation nuclei containing atoms of radon progeny.

  1. 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.

  2. The influence of thoron on instruments measuring radon activity concentration.

    PubMed

    Michielsen, N; Bondiguel, S

    2015-11-01

    Thoron, the isotope 220 of radon, is a radionuclide whose concentration may influence the measurement of the activity concentration of (222)Rn in the air. If in the case of continuous and active sampling measuring instruments, using a pump for example, the influence of thoron on radon measurement is obvious and is taken into account in the apparatus, it is often assumed that in the case of a passive sampling, by diffusion through a filter for example, this thoron influence is negligible. This is due to the very short radioactive half-life of thoron, 55.6 s (3.82 d for (222)Rn), and the assumption that the diffusion time of thoron in the detection chamber is long enough beside that of the thoron half-life. The objective of this study is to check whether this assumption is true or not for different kinds of commercial electronic apparatus used to measure radon activity concentration from soil to dwellings. First of all, the devices were calibrated in activity concentration of radon, and then they were exposed to a controlled thoron atmosphere. The experiments concerning the thoron aimed to investigate the sensitivity to thoron in the radon measuring mode of the apparatus. Results of these experiments show that all devices have a very quick answer to thoron atmosphere, even though the sensitivities vary from one instrument to another. Results clearly show that this influence on radon measurement due to the thoron is observed also after the exposition because of the decay of (212)Pb and its progenies. In conclusion, the sensitivity to thoron in the radon measuring mode depends strongly on the type of instruments. The results of the present investigation show that for some apparatus, the influence of thoron cannot be disregarded especially when measuring radon in soil.

  3. 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.

  4. 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.

  5. Time-dependent response of a charcoal bed to radon and water vapor in flowing air

    SciTech Connect

    Henkel, J.A.; Fentiman, A.W.; Blue, T.E.

    1995-12-31

    Extremely high airborne concentrations of radon gas may be encountered during the remediation of uranium mill tailings storage facilities. Radon is also a constituent of the off-gas of mill-tailing vitrification. An effective way to remove radon from either gas is to pass the gas through a packed bed containing activated charcoal. Measurements of radon concentrations in the environment using charcoal canisters were first described by George. Canisters similar to those used by George in his first experiments have become the U.S. Environmental Protection Agency`s (EPA`s) standard for measuring environmental radon and were described in the EPA protocol for environmental radon measurement. The dynamic behavior of EPA charcoal canisters has been previously described with a mathematical model for the kinetics of radon gas adsorption in air in the presence of water vapor. This model for charcoal canisters has been extended to large charcoal beds with flowing air containing radon and water vapor. The mathematical model for large charcoal beds can be used to evaluate proposed bed designs or to model existing beds. Parameters that affect the radon distribution within a charcoal bed that can be studied using the mathematical model include carrier gas relative humidity and flow velocity, and input radon concentration. In addition, the relative performances of several different charcoals can be studied, provided sufficient information about their adsorption, desorption, and diffusion constants is known.

  6. 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.

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

    SciTech Connect

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

    2009-05-22

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

  8. Assessment of the dose from radon and its decay products in the Bozkov dolomite cave.

    PubMed

    Rovenská, K; Thinová, L; Zdímal, V

    2008-01-01

    The dose from radon and its progeny remains a frequently discussed problem. ICRP 65 provides a commonly used methodology to calculate the dose from radon. Our work focuses on a cave environment and on assessing the doses in public open caves. The differences in conditions (aerosol size distribution, humidity, radon and its progeny ratio, etc.) are described by the so-called cave factor j. The cave factor is used to correct the dose for workers which is calculated using the ICRP 65 recommendation. In this work, the authors have brought together measured data of aerosol size distribution, unattached and attached fraction activity, and have calculated the so-called cave factor for the Bozkov dolomite cave environment. The dose conversion factors based on measured data and used for evaluating the cave factor were calculated by LUDEP software, which implements HRTM ICRP66.

  9. 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.

  10. Public perceptions of radon risk

    SciTech Connect

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

    1993-03-01

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

  11. 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 ...

  12. Atmosphere purification of radon and radon daughter elements

    DOEpatents

    Stein, L.

    1973-12-11

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

  13. 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

  14. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

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

  16. 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.

  17. 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...

  18. Radon: The Silent Danger.

    ERIC Educational Resources Information Center

    Stoffel, Jennifer

    1989-01-01

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

  19. 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

  20. 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.

  1. 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.

  2. 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

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

    PubMed

    Espinosa, G; Tommasino, L

    2015-05-01

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

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

    NASA Astrophysics Data System (ADS)

    Espinosa, G.; Tommasino, Luigi

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

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

    PubMed

    Espinosa, G; Tommasino, L

    2015-05-01

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

  6. Measurement of Radon, Thoron, Isotopic Uranium and Thorium to Determine Occupational and Environmental Exposure and Risk at Fernald Feed Material Production Center

    SciTech Connect

    Naomi H. Harley, Ph.D.

    2004-07-01

    To develop a new and novel area and personal radon/thoron detector for both radon isotopes to better measure the exposure to low airborne concentrations of these gases at Fernald. These measurements are to be used to determine atmospheric dispersion and exposure to radon and thoron prior to and during retrieval and removal of the 4000 Ci of radium in the two silos at Fernald.

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

    USGS Publications Warehouse

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

    1993-01-01

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

  8. 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.

  9. Nonhereditary enhancement of progeny growth

    NASA Technical Reports Server (NTRS)

    Khan, Amir S.; Fiorotto, Marta L.; Hill, Leigh-Anne; Malone, P. Brandon; Cummings, Kathleen K.; Parghi, Deena; Schwartz, Robert J.; Smith, Roy G.; Draghia-Akli, Ruxandra

    2002-01-01

    The im electroporated injection of a protease-resistant GH-releasing hormone cDNA into rat dams at 16 d gestation resulted in enhanced long-term growth of the F(1) offspring. The offspring were significantly heavier by 2 wk of age, and the difference was sustained to 10 wk of age. Consistent with their augmented growth, the plasma IGF-I concentration of the F(1) progeny was increased significantly. The pituitary gland of the offspring was significantly heavier and contained an increased number of somatotrophs and PRL-secreting cells, which is indicative of modification of cell lineage differentiation. These unique findings demonstrate that enhanced GH-releasing hormone expression in pregnant dams can result in intergenerational growth promotion by altering development of the pituitary gland in the offspring.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Problems Found Using a Radon Stripping Algorithm for Retrospective Assessment of Air Filter Samples

    SciTech Connect

    Robert Hayes

    2008-04-01

    An evaluation of a large number of air sample filters was undertaken using a commercial alpha and beta spectroscopy system employing a passive implanted planar silicon (PIPS) detector. Samples were only measured after air flow through the filters had ceased. Use of a commercial radon stripping algorithm was implemented to discriminate anthropogenic alpha activity on the filters from the radon progeny. When uncontaminated air filters were evaluated, the results showed that there was a time-dependent bias in both average estimates and measurement dispersion of anthropogenic activity estimates with the relative bias being small compared to the dispersion, indicating that the system would not give false positive indications for an appropriately set decision level. By also measuring environmental air sample filters simultaneously with electroplated alpha filters, use of the radon stripping algorithm demonstrated a number of substantial unexpected deviations from calibrated values indicating that the system would give false negative indications. Use of the current algorithm is, therefore, not recommended for general assay applications. Use of the PIPS detector should only be utilized for gross counting without appropriate modifications to the curve-fitting algorithm. As a screening method, the radon stripping algorithm might be expected to see elevated alpha activities on air sample filters (not due to radon progeny) around the 200 disintegrations per minute level.

  16. Use of a Radon Stripping Algorithm for Retrospective Assessment of Air Filter Samples

    SciTech Connect

    Robert Hayes

    2009-01-23

    An evaluation of a large number of air sample filters was undertaken using a commercial alpha and beta spectroscopy system employing a passive implanted planar silicon (PIPS) detector. Samples were only measured after air flow through the filters had ceased. Use of a commercial radon stripping algorithm was implemented to discriminate anthropogenic alpha and beta activity on the filters from the radon progeny. When uncontaminated air filters were evaluated, the results showed that there was a time-dependent bias in both average estimates and measurement dispersion with the relative bias being small compared to the dispersion. By also measuring environmental air sample filters simultaneously with electroplated alpha and beta sources, use of the radon stripping algorithm demonstrated a number of substantial unexpected deviations. Use of the current algorithm is therefore not recommended for assay applications and so use of the PIPS detector should only be utilized for gross counting without appropriate modifications to the curve fitting algorithm. As a screening method, the radon stripping algorithm might be expected to see elevated alpha and beta activities on air sample filters (not due to radon progeny) around the 200 dpm level.

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

    PubMed

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

    2014-01-01

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

  18. Airborne Transparencies.

    ERIC Educational Resources Information Center

    Horne, Lois Thommason

    1984-01-01

    Starting from a science project on flight, art students discussed and investigated various means of moving in space. Then they made acetate illustrations which could be used as transparencies. The projection phenomenon made the illustrations look airborne. (CS)

  19. Indoor radon survey in a university campus of Nigeria

    PubMed Central

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

    2010-01-01

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

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

    PubMed

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

    2010-10-01

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

  1. The modified model of radiation risk at radon exposure.

    PubMed

    Zhukovsky, Michael; Demin, Vladimir; Yarmoshenko, Ilia

    2014-07-01

    The combined modified model of risk assessment from an indoor radon exposure is proposed. Multiplicative dependence on fatal lung cancer is used. The model has been developed on the basis of the modern health risk theory and the results of epidemiological studies with the special attention to the results of the European combined study and the WISMUT miners cohort study. The model is presented as an age-specific relative risk coefficient for a single (short-term) exposure. The risk coefficient for an extended exposure can be obtained from this risk coefficient in the accordance with the risk theory. The smoothed dependences of the risk coefficients on time since exposure and attained age and radon progeny concentration are suggested.

  2. Radon dosimetry for a lung cancer study in Missouri

    SciTech Connect

    Alavanja, M.C.R.; Wood, M.; Hrubec, Z.; Boice, J.D. Jr.; Brownson, R.; Mahaffey, J.

    1992-12-31

    The power of any study to detect and quantify an association between lung cancer and residential radon exposure depends critically on the quality, completeness, and reliability of exposure data. To evaluate the adequacy of radon dosimetry in an ongoing case-control study of lung cancer in nonsmoking white women in Missouri, residential histories from 798 telephone interviews and year-long radon measurements from 250 study subjects were examined. An attempt was made to place alpha-track detectors in the bedroom and kitchen of every dwelling occupied by those subjects for the past 30 y (mean = 2.6 homes). The length of residence in current homes was 22 y on average. However, the proportion of women exceeding a 30-y, time-weighted, average concentration of 4 pCi L{sup {minus}1} significantly decreased with an increased number of residences. For those living in 1,2, and 3+ homes during the last 30 y, the percentages greater than 4 pCi L{sup {minus}1} were 11.3%, 5.6%, and 0%, respectively. These findings support recent theoretical modeling that points to a substantial reduction in statistical power to detect a radon-related lung-cancer risk in populations with high residential mobility. Statistical power is further reduced as the number of missing radon measurements increases. Missing data result when owners refuse measurements, when the dwelling has been torn down, or when structural changes are so severe that a current measurement has little relevance to past radon concentrations. Estimates of missing exposure data must then be based on assumptions of uncertain validity. A novel approach to estimating cumulative residential radon exposure involves affixing CR-39 detectors to glass objects, such as mirrors, that have been in the possession of the study subject for at least 20 y. Measurements of alpha-particle emissions from long-lived radon progeny that accumulated in the surfaces of these glass objects might reflect long-term radon exposures.

  3. Radon: Is it a problem

    SciTech Connect

    Hart, B.L.; Mettler, F.A.; Harley, N.H. )

    1989-09-01

    Radon gas is a major source of radiation exposure to the general public. Radon-222 is a product of uranium-238, present in varying concentrations in all soils. Radon enters buildings from soil, water, natural gas, and building materials. Its short-lived breakdown products, termed radon daughters, include alpha-emitting solids that can deposit in the lungs. Firm evidence links lung cancer risk in miners with high exposure to radon daughters. The amount of risk associated with the much lower but chronic doses received in buildings is difficult to establish. By some extrapolations, radon daughters may be responsible for a significant number of lung cancer deaths. The existence or extent of synergism with smoking is unresolved. Local conditions can cause high levels of radon in some buildings, and measures that reduce indoor radon are of potential value. 39 references.

  4. 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).

  5. The Effect of Grain Size on Radon Exhalation Rate in Natural-dust and Stone-dust Samples

    NASA Astrophysics Data System (ADS)

    Kumari, Raj; Kant, Krishan; Garg, Maneesha

    Radiation dose to human population due to inhalation of radon and its progeny contributes more than 50% of the total dose from the natural sources which is the second leading cause of lung cancer after smoking. In the present work the dependence of radon exhalation rate on the physical sample parameters of stone dust and natural dust were studied. The samples under study were first crushed, grinded, dried and then passed through sieves with different pore sizes to get samples of various grain sizes (μm). The average value of radon mass exhalation rate is 5.95±2.7 mBqkg-1hr-1 and average value of radon surface exhalation rate is 286±36 mBqm-2 hr-1 for stone dust, and the average value of radon mass exhalation rate is 9.02±5.37 mBqkg-1hr-1 and average value of radon surface exhalation rate is 360±67 mBqm-2 hr-1 for natural dust. The exhalation rate was found to increase with the increase in grain size of the sample. The obtained values of radon exhalation rate for all the samples are found to be under the radon exhalation rate limit reported worldwide.

  6. 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.

  7. 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.

  8. Collaborative investigations on thoron and radon in some rural communities of Balkans.

    PubMed

    Zunić, Z S; Celiković, I; Tokonami, S; Ishikawa, T; Ujić, P; Onischenko, A; Zhukovsky, M; Milić, G; Jakupi, B; Cuknić, O; Veselinović, N; Fujimoto, K; Sahoo, S K; Yarmoshenko, I

    2010-10-01

    This paper deals with the results of the first-field use in the Balkans, i.e. Serbia and Republic of Srpska (Bosnia and Hercegovina), of a passive polycarbonate Mark II type and poliallyldiglycol carbonate (Cr-39) alpha track detectors sensitive to thoron as well as to radon. Both types of solid state nuclear track detectors were designed and supplied by National Institute of Radiological Sciences (NIRS), Chiba, Japan. The commercial names for these detectors which all have been field tested in Balkan rural communities are known as: UFO and RADUET passive discriminative radon/thoron detectors. No database of thoron and thoron progeny concentrations in dwellings in Serbia or Balkans region exist, and as a result, the level of exposure of the Serbian population to thoron and its progeny is unknown so far. PMID:20966203

  9. 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.

  10. 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

  11. 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.

  12. Fourth Airborne Geoscience Workshop

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The focus of the workshop was on how the airborne community can assist in achieving the goals of the Global Change Research Program. The many activities that employ airborne platforms and sensors were discussed: platforms and instrument development; airborne oceanography; lidar research; SAR measurements; Doppler radar; laser measurements; cloud physics; airborne experiments; airborne microwave measurements; and airborne data collection.

  13. 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.

  14. 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.

  15. 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

  16. 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+.

  17. 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+.

  18. 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)

  19. Radon adsorbed in activated charcoal—a simple and safe radiation source for teaching practical radioactivity in schools and colleges

    NASA Astrophysics Data System (ADS)

    Al-Azmi, Darwish; Mustapha, Amidu O.; Karunakara, N.

    2012-07-01

    Simple procedures for teaching practical radioactivity are presented in a way that attracts students' attention and does not make them apprehensive about their safety. The radiation source is derived from the natural environment. It is based on the radioactivity of radon, a ubiquitous inert gas, and the adsorptive property of activated charcoal. Radon gas from ambient air in the laboratory was adsorbed into about 70 g of activated charcoal inside metallic canisters. Gamma radiation was subsequently emitted from the canisters, following the radioactive decay of radon and its progenies. The intensities of the emitted gamma-rays were measured at suitable intervals using a NaI gamma-ray detector. The counts obtained were analysed and used to demonstrate the radioactive decay law and determine the half-life of radon. In addition to learning the basic properties of radioactivity the students also get practical experience about the existence of natural sources of radiation in the environment.

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

    NASA Astrophysics Data System (ADS)

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

    2011-03-01

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

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

    SciTech Connect

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

    2011-03-30

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

  2. The measurements of thoron, radon and their decay products thanks to Pinocchio, Tengu and Trolls.

    PubMed

    Tommasino, L; Tokonami, S; Tommasino, P M

    2010-10-01

    In the present paper, the long noses of Pinocchio, Tengu and Trolls are used to measure, respectively, radon, thoron, and their decay products both by track-etch detectors and by Geiger-Müller (G-M) counters. Just recently, four new passive samplers (termed quatrefoil) have been developed which greatly simplify the detection of all airborne radionuclides by using either passive or real-time detectors. In particular, surface-deposited radon (thoron) decay products are sampled by films with large area and small surface density (0.1-1 mg cm(-2)). Once exposed, these films are stacked together for their detection by a pancake G-M counter. For the measurements of radon and thoron in soil, 25-cm-long tubes with sampling films along their internal surfaces can be successfully used. Once exposed, these films can be counted by a pancake G-M for the selective measurement of radon and thoron.

  3. Dosimetry of radon and thoron exposures: Implications for risks from indoor exposure

    SciTech Connect

    James, A.C.

    1992-12-31

    Current estimates of lung-cancer risks due to the inhalation of radon and its progeny in homes are based on extrapolations of excess mortality observed in populations of underground miners. To project lung-cancer risk to the general public it is necessary to account for any effects that different exposure conditions may have on doses received by critical target cells in the respiratory tract. This paper summarizes the results of a review of aerosol parameters, physiological and biological factors, and cells at risk that are involved in comparing doses between mine and indoor environments. The dose received by sensitive cells in the bronchi from exposure to a given amount of potential alpha-energy (commonly given the unit Working Level Month, WLM) is found to be approximately 20% lower indoors that for healthy underground miners. However, this estimate of the ratio of dose per unit exposure in homes compared to that in mines (termed the {open_quotes}K-factor{close_quotes}) is sensitive to the assumed hygroscopic properties of radon-progeny aerosols. The estimate of K varies from about 0.9, if radon-progeny aerosol particles are assumed not to grow hygroscopically in the respiratory tract, to about 0.6 if the ambient particles are assumed to double in size by hygroscopic growth.

  4. 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.

  5. 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

  6. Airborne Imagery

    NASA Technical Reports Server (NTRS)

    1983-01-01

    ATM (Airborne Thematic Mapper) was developed for NSTL (National Space Technology Companies) by Daedalus Company. It offers expanded capabilities for timely, accurate and cost effective identification of areas with prospecting potential. A related system is TIMS, Thermal Infrared Multispectral Scanner. Originating from Landsat 4, it is also used for agricultural studies, etc.

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

    PubMed

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

    2013-06-01

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

  8. 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

  9. 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.

  10. 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...

  11. 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.

  12. A novel detection of radon based on its decay product inducing conformational changes of an aptamer probe.

    PubMed

    Long, Minzhi; Deng, Han; Tian, Gang; Song, Chunli; Liu, Hongwen; Shen, Yi; Lv, Changyin

    2016-09-14

    This study proposes a novel method for the detection of inert gas radon using a label-free, specific, fluorescence-sensing aptamer in the context of PW17-OG system. This method utilizes the cyanine dye OliGreen (OG) as a signal reactor and the aptamer PW17 as a fluorescent identification probe. When OG integrates into the free curling PW17, a strong fluorescence signal is generated. After radon decays, the long lived naturally occurring radon progeny Pb being disposed and introduced to the system. Lead ions induce PW17 to form a stable G-quadruplex, thereby inhibiting the interaction between OG and PW17 and resulting in a reduction of the fluorescence intensity. The fluorescence intensity show a good linear relationship with lead ion and the radon concentration (D), thereinto, We fitted linear regression of radon concentration in the range of 0.92-4.22 (×10(4) Bqhm(-3)) to receive a good relationship between ΔF and the concentration of radon with the detection limit of 1963 Bqhm(-3). This method has been successfully applied for detecting standard cumulative concentration of radon and the detection limit reached the national standard of China. This sensitive method can exclude radiation damage in field testing, furthermore, it explores a new field in biological analysis using an aptamer to detected inorganic, gaseous, and radioactive materials.

  13. A novel detection of radon based on its decay product inducing conformational changes of an aptamer probe.

    PubMed

    Long, Minzhi; Deng, Han; Tian, Gang; Song, Chunli; Liu, Hongwen; Shen, Yi; Lv, Changyin

    2016-09-14

    This study proposes a novel method for the detection of inert gas radon using a label-free, specific, fluorescence-sensing aptamer in the context of PW17-OG system. This method utilizes the cyanine dye OliGreen (OG) as a signal reactor and the aptamer PW17 as a fluorescent identification probe. When OG integrates into the free curling PW17, a strong fluorescence signal is generated. After radon decays, the long lived naturally occurring radon progeny Pb being disposed and introduced to the system. Lead ions induce PW17 to form a stable G-quadruplex, thereby inhibiting the interaction between OG and PW17 and resulting in a reduction of the fluorescence intensity. The fluorescence intensity show a good linear relationship with lead ion and the radon concentration (D), thereinto, We fitted linear regression of radon concentration in the range of 0.92-4.22 (×10(4) Bqhm(-3)) to receive a good relationship between ΔF and the concentration of radon with the detection limit of 1963 Bqhm(-3). This method has been successfully applied for detecting standard cumulative concentration of radon and the detection limit reached the national standard of China. This sensitive method can exclude radiation damage in field testing, furthermore, it explores a new field in biological analysis using an aptamer to detected inorganic, gaseous, and radioactive materials. PMID:27566356

  14. Ambient airborne [sup 222]Rn concentrations at selected Hanford Site facilities

    SciTech Connect

    Atencio, E.M.; Gleckler, B.P.; Smith, C.Y.

    1993-01-01

    Summary of ambient airborne [sup 222]Rn concentrations measured at selected US Department of Energy Hanford Site facilities located in southeastern Washington. Measurements were made using a 3 [times] 3 sodium-iodide gamma spectroscopy counting system, and then quantified using verified and validated computer software. Over the last 2 years, eight Hanford Site facilities were thoroughly characterized, the results are presented. The facilities characterized in response to the Indoor Radon Abatement Act, Public Law 100--551. Results from test samples reveal relatively low levels of airborne radon.

  15. Ambient airborne {sup 222}Rn concentrations at selected Hanford Site facilities

    SciTech Connect

    Atencio, E.M.; Gleckler, B.P.; Smith, C.Y.

    1993-01-01

    Summary of ambient airborne {sup 222}Rn concentrations measured at selected US Department of Energy Hanford Site facilities located in southeastern Washington. Measurements were made using a 3 {times} 3 sodium-iodide gamma spectroscopy counting system, and then quantified using verified and validated computer software. Over the last 2 years, eight Hanford Site facilities were thoroughly characterized, the results are presented. The facilities characterized in response to the Indoor Radon Abatement Act, Public Law 100--551. Results from test samples reveal relatively low levels of airborne radon.

  16. 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.

  17. Radon mapping strategies in Austria.

    PubMed

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

    2015-11-01

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

  18. Radon concentrations in residential housing in Hiroshima and Nagasaki

    SciTech Connect

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

    1995-05-01

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

  19. (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.

  20. Radon induced surface contaminations in low background experiments

    SciTech Connect

    Pattavina, L.

    2013-08-08

    In neutrinoless double-beta decay and dark matter searches, one of the main issues is to increase the experimental sensitivity through careful material selection and production, minimizing the background contributions. In order to achieve the required, extremely low, counting rates, very stringent requirements must be fulfilled in terms of bulk material radiopurity. As the experimental sensitivity increases, the bulk impurities in the detector components decrease, and surface contaminations start to play an increasingly significant role In fully active detectors, like cryogenic particle detectors, surface contaminations are a critical issue (as shown by the CUORICINO experiment). {sup 222}Rn is by far the most intense source of airborne radioactivity, and if a radio-pure material is exposed to environment where the Radon concentration is not minimized, {sup 210}Pb and {sup 210}Po contaminations can occur. The mechanisms and the dynamics of Radon-induced surface contaminations are reviewed, and specific solutions to prevent and to reject the induced background are presented.

  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. Progeny from dedifferentiated adipocytes display protracted adipogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Progeny of adipofibroblast cells, derived from mature bovine adipocytes, were used to determine their ability to redifferentiate into lipid-assimilating adipocytes. Traditional cell biology methods were used, including the expression of adipogenic markers such as PPAR'. When exposed to medium supple...

  3. 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

  4. 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.

  5. The health risks of radon: The BEIR IV report and beyond

    SciTech Connect

    Fabrikant, J.I.

    1989-06-01

    The National Academy of Sciences' BEIR IV Report deals with the health effects in human populations exposed to internally-deposited alpha-emitting radionuclides and their decay products. Quantitative risk estimates for cancer induction are derived, mainly from analyses of epidemiological data. The Report addresses the health outcomes of exposure to radon and its daughters, primarily lung cancer risks of worker exposure to radon progeny in underground mines and in the general public in indoor domestic environments. An excess relative risk model of lung cancer mortality and exposure to radon progeny is developed; this models the excess risk per Working Level Month in terms of time intervals prior to an attained age, and is dependent on time-since-exposure and age at risk. Risk projections are presented and cover exposure situations of current public health concern. For example, the lifetime risk of lung cancer mortality due to lifetime exposure to radon progeny in terms of WLM and alpha-particle dose to the target cells of the bronchial epithelium is estimated to be 350 excess deaths per million person-WLM. Lifetime exposure to 1 WLM y /sub /minus/1/ is estimated to increase the number of deaths due to lung cancer by a factor of about 1.5 over the current rate for both males and females in a population having the current prevalence of cigarette-smoking. Occupational exposure to 4 WLM y/sub /minus/1/ from ages 20 y to 40 y is projected to increase lung cancer deaths by a factor of 1.6 over the current rate of this age cohort in the general population. In all of these cases, most of the increased risk occurs to smokers for who the risk is up to ten times greater than for nonsmokers. 10 refs., 1 tab.

  6. Radon and radon daughter measurements in solar buildings.

    PubMed

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

    1983-08-01

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

  7. 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.

  8. Does long term exposure to radon gas influence the properties of polymeric waterproof materials?

    NASA Astrophysics Data System (ADS)

    Navratilova Rovenska, Katerina; Jiranek, Martin; Kokes, Pavel; Wasserbauer, Richard; Kacmarikova, Veronika

    2014-01-01

    The technical state of buildings and the quality of the indoor environment depend on the quality of the waterproofing course and on the properties of the insulating materials that are applied, in particular on their durability, long-term functional reliability and resistance to corrosive effects of the subsoil. Underground water chemistry and soil bacteria are well-known corrosive agents. Our investigations indicate that the ageing process of waterproof materials can be significantly accelerated by alpha particles emitted by radon and radon progenies which are present in soil gas. Materials commonly available on the building market, e.g. LDPE and HDPE of various densities, PVC, TPO (thermoplastic polyolefin), PP (polypropylene) and EPDM were selected for our experimental study. The preliminary results for 3-year exposure to radon gas show a decrease in tensile strength to 60%, elongation to 80% and hardness to 95% for samples based on PE. The diffusion coefficient of radon for samples based on PVC decreased to 20% of the initial value after 1-year exposure to radon and soil bacteria.

  9. Radon exposure in uranium mining industry vs. exposure in tourist caves.

    PubMed

    Quindós Poncela, L; Fernández Navarro, P; Sainz Fernández, C; Gómez Arozamena, J; Bordonoba Perez, M

    2004-01-01

    There is a fairly general consensus among health physicists and radiation professionals that exposure to radon progeny is the largest and most variable contribution to the population's exposure to natural sources of radiation. However, this exposure is the subject of continuing debate concerning the validity of risk assessment and recommendations on how to act in radon-prone areas. The purpose of this contribution is to situate the radon issue in Spain in two very different settings. The first is a uranium mining industry located in Saelices el Chico (Salamanca), which is under strict control of the Spanish Nuclear Safety Council (CSN). We have measured radon concentrations in different workplaces in this mine over a five-year period. The second setting comprises four tourist caves, three of which are located in the province of Cantabria and the fourth on the Canary Island of Lanzarote. These caves are not subject to any administrative control of radiation exposure. Measured air 222Rn concentrations were used to estimate annual effective doses due to radon inhalation in the two settings, and dose values were found to be from 2 to 10 times lower in the uranium mine than in the tourist caves. These results were analysed in the context of the new European Basic Safety Standards Directive (EU-BSS, 1996).

  10. 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.

  11. 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...

  12. 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...

  13. Observations and modelling of thoron and its progeny in the soil-atmosphere-plant system.

    PubMed

    Baldacci, A E; Gattavecchia, E; Kirchner, G

    2010-11-01

    Samples of pasture vegetation, mainly Trifolium pratensis, were collected at the Botanic Garden of the University of Bologna during the period 1998-2000 and measured by gamma-spectrometry for determining thoron progeny. Concentrations of (212)Pb were between 1.5 and 20 Bq m(-2), with individual peaks up to 70 Bq m(-2). Soil samples were collected at the same location and physically characterised. Their chemical composition (particularly Th and U) was determined by X-ray fluorescence spectroscopy. Lead-212 on plants mainly originates from dry and wet deposition of this isotope generated in the lower atmosphere by the decay of its short-lived precursor (220)Rn, which is produced in the upper soil layers as a member of the natural thorium decay chain and exhales into the atmosphere. Concentrations of (220)Rn in the atmosphere depend on (1) the amount of Th present in soil, (2) the radon fraction which escapes from the soil minerals into the soil pore space, (3) its transport into the atmosphere, and (4) its redistribution within the atmosphere. The mobility of radon in soil pore space can vary by orders of magnitude depending on the soil water content, thus being the main factor for varying concentrations of (220)Rn and (212)Pb in the atmosphere. We present a simple model to predict concentrations of thoron in air and its progeny deposited from the atmosphere, which takes into account varying soil moisture contents calculated by the OPUS code. Results of this model show close agreement with our observations.

  14. An overview of the North American residential radon and lung cancer case-control studies.

    PubMed

    Field, R William; Krewski, Daniel; Lubin, Jay H; Zielinski, Jan M; Alavanja, Michael; Catalan, Vanessa S; Klotz, Judith B; Létourneau, Ernest G; Lynch, Charles F; Lyon, Joseph L; Sandler, Dale P; Schoenberg, Janet B; Steck, Daniel J; Stolwijk, Jan A; Weinberg, Clarice; Wilcox, Homer B

    2006-04-01

    Lung cancer has held the distinction as the most common cancer type worldwide since 1985 (Parkin et al., 1993). Recent estimates suggest that lung cancer accounted for 1.2 million deaths worldwide in 2002, which represents 17.6% of the global cancer deaths (Parkin et al., 2005). During 2002, the highest lung cancer rates for men worldwide reportedly occurred in North America and Eastern Europe, whereas the highest rates in females occurred in North America and Northern Europe (Parkin et al., 2005). While tobacco smoking is the leading risk factor for lung cancer, because of the magnitude of lung cancer mortality, even secondary causes of lung cancer present a major public health concern (Field, 2001). Extrapolations from epidemiologic studies of radon-exposed miners project that approximately 18,600 lung cancer deaths per year (range 3000 to 41,000) in the United States alone are attributable to residential radon progeny exposure (National Research Council, 1999). Because of differences between the mines and the home environment, as well as differences (such as breathing rates) between miners and the general public, there was a need to directly evaluate effects of radon in homes. Seven major residential case-control radon studies have been conducted in North America to directly examine the association between prolonged radon progeny (radon) exposure and lung cancer. Six of the studies were performed in the United States including studies in New Jersey, Missouri (two studies), Iowa, and the combined states study (Connecticut, Utah, and southern Idaho). The seventh study was performed in Winnipeg, Manitoba, Canada. The residential case-control studies performed in the United States were previously reviewed elsewhere (Field, 2001). The goal of this review is to provide additional details regarding the methodologies and findings for the individual studies. Radon concentration units presented in this review adhere to the types (pCi/L or Bq/m3) presented in the

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

    USGS Publications Warehouse

    Lindsey, Bruce D.; Ator, Scott W.

    1996-01-01

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

  16. Modeling of radon and its short-lived decay products emanating from tap water used inside a house: dose to adult members of the public.

    PubMed

    Ouabi, H

    2009-01-01

    Radon concentrations are measured in the tap water collected in different areas in Marrakech (Morocco) by using liquid scintillation techniques. The concentrations due to radon and its short-lived decay products emanating from the tap water used inside different compartments of the house were determined. Alpha activities due to the (218)Po and (214)Po short-lived radon decay products were evaluated in various compartments of the respiratory tract of adult members of the public. The committed equivalent doses due to the (218)Po and (214)Po short-lived progeny of radon were evaluated in different tissues of the respiratory tract by the frequencies of using the various parts of the house. PMID:18789711

  17. Response of direct thoron progeny sensors (DTPS) to various aerosol concentrations and ventilation rates

    NASA Astrophysics Data System (ADS)

    Mishra, Rosaline; Prajith, R.; Sapra, B. K.; Mayya, Y. S.

    2010-03-01

    Direct thoron/radon progeny sensors (DTPS/DRPS) are absorber mounted LR115 type track detectors for measuring the time-averaged progeny concentrations. Through a large number of experiments, the sensitivity factor of these sensors in natural indoor environment was found to be nearly constant at a value of 0.94 Tr cm -2 d -1/EETC (Bq m -3) for DTPS and 0.09 Tr cm -2 d -1/EERC (Bq m -3) for DRPS. The constancy of the sensitivity factor in the natural environments is attributed primarily to the presence of large aerosol concentrations and relatively low ventilation rates in time-averaged measurements. However, detailed model calculations suggest that in extreme scenario i.e. at high ventilation rate and low aerosol concentrations, the sensitivity factor can be quite different. Such situations are likely to occur in occupational plant areas. Therefore systematic chamber experiments were carried out to using DTPS, to estimate the variability of the sensitivity factor in these extreme conditions. In the first set, the sensitivity factor of DTPS was measured in 6 different aerosol concentrations at zero ventilation rates. The sensitivity factor showed a steep decrease as the aerosol concentration increased to about 8554 particle cm -3, after which it remained almost constant with increase in aerosol concentration. The second set of experiments was conducted at ˜5000 particles cm -3 at three different ventilation rates. The sensitivity factor was found to increase with increase in ventilation rate. The results are further discussed.

  18. 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.

  19. A macroscopic and microscopic study of radon exposure using Geant4 and MCNPX to estimate dose rates and DNA damage

    NASA Astrophysics Data System (ADS)

    van den Akker, Mary Evelyn

    Radon is considered the second-leading cause of lung cancer after smoking. Epidemiological studies have been conducted in miner cohorts as well as general populations to estimate the risks associated with high and low dose exposures. There are problems with extrapolating risk estimates to low dose exposures, mainly that the dose-response curve at low doses is not well understood. Calculated dosimetric quantities give average energy depositions in an organ or a whole body, but morphological features of an individual can affect these values. As opposed to human phantom models, Computed Tomography (CT) scans provide unique, patient-specific geometries that are valuable in modeling the radiological effects of the short-lived radon progeny sources. Monte Carlo particle transport code Geant4 was used with the CT scan data to model radon inhalation in the main bronchial bifurcation. The equivalent dose rates are near the lower bounds of estimates found in the literature, depending on source volume. To complement the macroscopic study, simulations were run in a small tissue volume in Geant4-DNA toolkit. As an expansion of Geant4 meant to simulate direct physical interactions at the cellular level, the particle track structure of the radon progeny alphas can be analyzed to estimate the damage that can occur in sensitive cellular structures like the DNA molecule. These estimates of DNA double strand breaks are lower than those found in Geant4-DNA studies. Further refinements of the microscopic model are at the cutting edge of nanodosimetry research.

  20. Emanation of radon from household granite.

    PubMed

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

    2009-04-01

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

  1. 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.

  2. 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.

  3. 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...

  4. Analysis of lung tumor risks in rats exposed to radon.

    PubMed

    Gilbert, E S; Cross, F T; Dagle, G E

    1996-03-01

    Using data on 3117 rats exposed by inhalation to radon, radon progeny and uranium ore dust, the hazard function (or age-specific risk) for lung tumor incidence was modeled as a function of exposure, exposure rate and other factors. The overall estimate of lifetime risk was 237 cases per 10(6) rats per WLM (237 per 10(6) WLM), reasonably comparable to estimates obtained from data for humans. The data below 1000 WLM (20-640 WLM) were consistent with linearity with positive excess risks at all levels; however, evidence of statistically significant excess risk was limited to exposures of 80 WLM or greater. Evidence for an inverse exposure-rate effect was limited primarily to cumulative exposures exceeding 1000 WLM (1280-10,240 WLM) and to comparison of results at 100 and 1000 WL. Even at these levels, the possibility that the effect might be explained by time since last exposure or by heterogeneity across experiments could not be entirely excluded. The inverse exposure-rate effect was strongest for epidermoid and adenosquamous tumors, and the only indication of such an effect at exposures below 1000 WLM was modest evidence (P=0.024) in analyses limited to these tumors. When all lung tumors, or all malignant lung tumors, were included, there was no evidence of such an effect below 1000 WLM. These data support the viewpoint that the inverse exposure-rate effect is primarily a high-dose phenomenon. PMID:8927704

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

    SciTech Connect

    Dixon, K.; Phifer, M.

    2010-07-30

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

  6. 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

    outside of the basement walls, then into the basement through cracks and openings. During the final six weeks of the study, measurements were made with the water level in the sump maintained first below, then above the entrance of the pipe connected to the perimeter drain tile system. Average indoor radon concentrations during these two periods were 10.6 and 3.5 pCi {ell}{sup -1} (390 and 130 Bq m{sup -3}), respectively. The relatively high latter value compared with the mean for the first 15 weeks, combined with the observation of intervals of high airborne alpha activity at the sump during this period, suggest that the level of water in the sump does not, by itself, account for the variation in alpha activity at the sump that we had previously observed. Fireplace operation substantially increased the air-exchange state, but had only a small effect on indoor radon concentration, providing corroborative evidence that pressure-driven flow is an important mechanism for radon entry into this house.

  7. 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.

  8. Radon detection in conical diffusion chambers: Monte Carlo calculations and experiment

    SciTech Connect

    Rickards, J.; Golzarri, J. I.; Espinosa, G.; Vázquez-López, C.

    2015-07-23

    The operation of radon detection diffusion chambers of truncated conical shape was studied using Monte Carlo calculations. The efficiency was studied for alpha particles generated randomly in the volume of the chamber, and progeny generated randomly on the interior surface, which reach track detectors placed in different positions within the chamber. Incidence angular distributions, incidence energy spectra and path length distributions are calculated. Cases studied include different positions of the detector within the chamber, varying atmospheric pressure, and introducing a cutoff incidence angle and energy.

  9. 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.

  10. 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

  11. 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.

  12. [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.

  13. 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.

  14. 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...

  15. 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.

  16. 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.

  17. 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)

  18. 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…

  19. 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…

  20. Radon-induced alterations in p53-mediated energy metabolism of malignantly transformed human bronchial epithelial cells.

    PubMed

    Liu, Xing; Wang, Xu; Tong, Jian

    2016-01-01

    Radon and its progeny were confirmed to be a category I carcinogenic agent. However, the molecular basis underlying carcinogenesis induced by radon has not been fully elucidated. Expression of p53, a key regulator in glycolysis, is known to be decreased in carcinogenesis. The aim of this investigation was to determine changes in energy metabolism mediated by p53-related metabolic pathway using radon-induced transformation of human bronchial epithelial (HBE) cells. HBE cells were exposed to radon for 20 min at a concentration of 20,000 Bq/m(3) and cultured for 3 d, and exposed again at the same concentration and duration. This was repeated 10 times with culture for 35 passages until malignant transformation occurred. During the culturing process, the levels of lactate and lactate dehydrogenase (LDH) and ratio of NAD(+)/NADH gradually increased between passages. Between passages 30 and 35, p53 target gene synthesis of cytochrome c oxidase 2 (SCO2), TP53-induced glycolysis, and apoptosis regulator (TIGAR) expression were significantly decreased. Data demonstrated that p53-associated metabolic pathways may be altered in radon-mediated malignant transformation. PMID:27267826

  1. Investigation of radon entry and effectiveness of mitigation measures in seven houses in New Jersey: Midproject report

    SciTech Connect

    Matthews, T.G.; Dudney, C.S.; Monar, K.P.; Landguth, D.C.; Wilson, D.L.; Hawthorne, A.R.; Hubbard, L.M.; Gadsby, K.J.; Bohac, D.L.; Decker, C.A.

    1987-12-01

    A detailed radon mitigation study is in progress in 14 homes in the New Jersey Piedmont area. The principal goals are the refinement of diagnostic measurements for selection and implementation of mitigation systems, and the reduction of radon concentrations to acceptable levels inside the study houses. Monitoring stations were installed in each home in October, 1986. Instrumented measurements included: basement and upstairs radon; differential pressures across the basement/subslag, basement/upstairs and basement/outdoor interfaces; temperatures at basement, upstairs and outdoor locations; and central air handler usage. A weather station was located at one house, monitoring wind speed and direction; barometric pressure; precipitation; soil temperature; and outdoor temperature and relative humidity. A time-averaged value of all of the above parameters was recorded every 30 min. Several additional parameters were monitored on an intermittent basis in all or selected homes. These include multizone air infiltration rates which have been measured in all homes using passive perfluorocarbon tracers (PFT) and in two homes using a constant concentration tracer gas system (CCTG). Total radon progeny, soil gas radon concentration and permeability characteristics, and gamma radiation levels were also monitored periodically in all study homes. 10 refs., 53 figs.

  2. 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.

  3. 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).

  4. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2009-05-01

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

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  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. 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.

  20. 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...

  1. 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...

  2. The Cellular and Molecular Carcinogenic Effects of Radon Exposure: A Review

    PubMed Central

    Robertson, Aaron; Allen, James; Laney, Robin; Curnow, Alison

    2013-01-01

    Radon-222 is a naturally occurring radioactive gas that is responsible for approximately half of the human annual background radiation exposure globally. Chronic exposure to radon and its decay products is estimated to be the second leading cause of lung cancer behind smoking, and links to other forms of neoplasms have been postulated. Ionizing radiation emitted during the radioactive decay of radon and its progeny can induce a variety of cytogenetic effects that can be biologically damaging and result in an increased risk of carcinogenesis. Suggested effects produced as a result of alpha particle exposure from radon include mutations, chromosome aberrations, generation of reactive oxygen species, modification of the cell cycle, up or down regulation of cytokines and the increased production of proteins associated with cell-cycle regulation and carcinogenesis. A number of potential biomarkers of exposure, including translocations at codon 249 of TP53 in addition to HPRT mutations, have been suggested although, in conclusion, the evidence for such hotspots is insufficient. There is also substantial evidence of bystander effects, which may provide complications when calculating risk estimates as a result of exposure, particularly at low doses where cellular responses often appear to deviate from the linear, no-threshold hypothesis. At low doses, effects may also be dependent on cellular conditions as opposed to dose. The cellular and molecular carcinogenic effects of radon exposure have been observed to be both numerous and complex and the elevated chronic exposure of man may therefore pose a significant public health risk that may extend beyond the association with lung carcinogenesis. PMID:23880854

  3. The cellular and molecular carcinogenic effects of radon exposure: a review.

    PubMed

    Robertson, Aaron; Allen, James; Laney, Robin; Curnow, Alison

    2013-07-05

    Radon-222 is a naturally occurring radioactive gas that is responsible for approximately half of the human annual background radiation exposure globally. Chronic exposure to radon and its decay products is estimated to be the second leading cause of lung cancer behind smoking, and links to other forms of neoplasms have been postulated. Ionizing radiation emitted during the radioactive decay of radon and its progeny can induce a variety of cytogenetic effects that can be biologically damaging and result in an increased risk of carcinogenesis. Suggested effects produced as a result of alpha particle exposure from radon include mutations, chromosome aberrations, generation of reactive oxygen species, modification of the cell cycle, up or down regulation of cytokines and the increased production of proteins associated with cell-cycle regulation and carcinogenesis. A number of potential biomarkers of exposure, including translocations at codon 249 of TP53 in addition to HPRT mutations, have been suggested although, in conclusion, the evidence for such hotspots is insufficient. There is also substantial evidence of bystander effects, which may provide complications when calculating risk estimates as a result of exposure, particularly at low doses where cellular responses often appear to deviate from the linear, no-threshold hypothesis. At low doses, effects may also be dependent on cellular conditions as opposed to dose. The cellular and molecular carcinogenic effects of radon exposure have been observed to be both numerous and complex and the elevated chronic exposure of man may therefore pose a significant public health risk that may extend beyond the association with lung carcinogenesis.

  4. 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.

  5. Dosimetry of radium-223 and progeny

    SciTech Connect

    Fisher, D.R.; Sgouros, G.

    1999-01-01

    Radium-223 is a short-lived (11.4 d) alpha emitter with potential applications in radioimmunotherapy of cancer. Radium-223 can be complexed and linked to protein delivery molecules for specific tumor-cell targeting. It decays through a cascade of short-lived alpha- and beta-emitting daughters with emission of about 28 MeV of energy through complete decay. The first three alpha particles are essentially instantaneous. Photons associated with Ra-223 and progeny provide the means for tumor and normal-organ imaging and dosimetry. Two beta particles provide additional therapeutic value. Radium-223 may be produced economically and in sufficient amounts for widescale application. Many aspects of the chemistry of carrier-free isotope preparation, complexation, and linkage to the antibody have been developed and are being tested. The radiation dosimetry of a Ra-223-labeled antibody shows favorable tumor to normal tissue dose ratios for therapy. The 11.4-d half-life of Ra-223 allows sufficient time for immunoconjugate preparation, administration, and tumor localization by carrier antibodies before significant radiological decay takes place. If 0.01 percent of a 37 MBq (1 mCi) injection deposits in a one gram tumor mass, and if the activity is retained with a typical effective half-time (75 h), the absorbed dose will be 163 mGy MBq{sup {minus}1} (600 rad mCi{sup {minus}1}) administered. 49 refs., 5 figs., 2 tabs.

  6. 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.

  7. 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.

  8. 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.

  9. The unattached fraction of radon decay products: Potential effects of in-home air cleaners on lung cancer risk

    SciTech Connect

    Brady, P.A.

    1991-01-01

    Radon decay products are a factor in the development of lung cancer. Because of their efficient deposition within the lung, the fraction of decay products not attached to particulate (i.e., the unattached fraction) is very important in lung dosimetry. This study simulated the use of two in-home air cleaning devices to reduce airborne particulate concentrations, measure the effect on the unattached fraction, and estimate the radon lung cancer risk. Radon was released into a chamber having a volume-to-surface-area ratio similar to a small home. At radon-decay product equilibrium, radon and airborne particle concentrations were measured, and the concentration of the unattached fraction was estimated. The effect of particle concentration on the unattached fraction was then determined. The average unattached fractions corresponding to the particle concentration ranges expected for the air cleaning devices were used to calculate the annual alpha radiation dose and annual radon lung cancer for men, women and children at rest and under light activity. The annual doses and related risks were compared to those used in the models published by the Environmental Protection Agency. For particulate concentrations of a home with no particulate generating activities (e.g., smoking, cooking), the electronic air cleaner is predicted to reduce the unattached fraction from seven percent (the value used by the NCRP and confirmed in this study) to four percent. These conditions represent the maximum reduction in the unattached fraction. The decrease in the unattached fraction is tentatively attributed to an increase in plateout. Based on these results, a reduction of less than ten percent in the calculated annual lung cancer risk is found in all cases.

  10. 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

  11. 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

  12. Residence times of fine tropospheric aerosols as determined by {sup 210}Pb progeny.

    SciTech Connect

    Marley, N. A.; Gaffney, J. S.; Drayton, P. J.; Cunningham, M. M.; Mielcarek, C.; Ravelo, R.; Wagner, C.

    1999-10-05

    Fine tropospheric aerosols can play important roles in the radiative balance of the atmosphere. The fine aerosols can act directly to cool the atmosphere by scattering incoming solar radiation, as well as indirectly by serving as cloud condensation nuclei. Fine aerosols, particularly carbonaceous soots, can also warm the atmosphere by absorbing incoming solar radiation. In addition, aerosols smaller than 2.5 {micro}m have recently been implicated in the health effects of air pollution. Aerosol-active radioisotopes are ideal tracers for the study of atmospheric transport processes. The source terms of these radioisotopes are relatively well known, and they are removed from the atmosphere only by radioactive decay or by wet or dry deposition of the host aerosol. The progeny of the primordial radionuclide {sup 238}U are of particular importance to atmospheric studies. Uranium-238 is common throughout Earth's crust and decays to the inert gas {sup 222}Rn, which escapes into the atmosphere. Radon-222 decays by the series of alpha and beta emissions shown in Figure 1 to the long-lived {sup 210}Pb. Once formed, {sup 210}Pb becomes attached to aerosol particles with average attachment times of 40 s to 3 min.

  13. Regional deposition of thoron progeny in models of the human tracheobronchial tree

    SciTech Connect

    Smith, S.M.; Cheng, Yung-Sung; Yeh, Hsu-Chi

    1995-12-01

    Models of the human tracheobronchial tree have been used to determine total and regional aerosol deposition of inhaled particles. Particle sizes measured in these studies have all been > 40 nm in diameter. The deposition of aerosols < 40 nm in diameter has not been measured. Particles in the ultrafine aerosol size range include some combustion aerosols and indoor radon progeny. Also, the influence of reduced lung size and airflow rates on particle deposition in young children has not been determined. With their smaller lung size and smaller minute volumes, children may be at increased risk from ultrafine pollutants. In order to accurately determine dose of inhaled aerosols, the effects of particle size, minute volume, and age at exposure must be quantified. The purpose of this study was to determine the deposition efficiency of ultrafine aerosols smaller than 40 nm in diameter in models of the human tracheobronchia tree. This study demonstrates that the deposition efficiency of aerosols in the model of the child`s tracheobronchial tree may be slightly higher than in the adult models.

  14. High-LET alpha-emitters: Radon, lung cancer and smoking

    SciTech Connect

    Fabrikant, J.I.

    1988-11-01

    The National Academy of Sciences BEIR IV Report deals with the health effects in human populations exposed to internally-deposited alpha-emitting radionuclides and their decay products. Quantitative risk estimates for cancer induction are derived, mainly from analyses of epidemiological data. The Report addresses the health outcomes of exposure to radon and its daughters, primarily lung cancer risks of worker exposure to radon progeny in underground mines and in the general public in indoor domestic environments. An excess relative risk model of lung cancer mortality and exposure to radon progeny is developed; this models the excess risk per Working Level Month in terms of time intervals prior to an attained age, and is dependent on time-since-exposure and age at risk. Risk projections are presented and cover exposure situations of current public health concern. For example, lifetime exposure to 1 WLM y/sup /minus/1/ is estimated to increase the number of deaths due to lung cancer by a factor of about 1.5 over the current rate for both males and females in a population having the current prevalence of cigarette-smoking. Occupational exposure to 4 WLM y/sup /minus/1/ from ages 20 y to 40 y is projected to increase lung cancer deaths by a factor of 1.6 over the current rate of this age cohort in the general population. In all of these cases, most of the increased risk occurs to smokers for whom the risk is up to ten times greater than for non-smokers. 8 refs., 1 tab.

  15. 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.

  16. 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.

  17. A further study of the (CR LR) difference technique for retrospective radon exposure assessment

    NASA Astrophysics Data System (ADS)

    Nikezic, D.; Yip, C. W. Y.; Leung, S. Y. Y.; Leung, J. K. C.; Yu, K. N.

    2006-12-01

    The (CR-LR) difference technique, based on the CR-39 and LR 115 detectors, for the determination of implanted 210Po in glass after deposition of short-lived radon progeny, was analyzed in details in this paper. The sensitivities of both detectors were calculated using the Monte Carlo method with V functions particularly derived in our previous works for the detectors used in the present experiments. The dependency of the sensitivity ratio on the removed layer of both detectors was determined and verified experimentally. The simulated sensitivity ratios correlate well with the experimental ones. A major finding of the present work is that the sensitivity ratio between the CR-39 and LR 115 detectors depends only weakly on the ratio between the 238U and 232Th concentrations in the glass samples. This is crucial for the application of the (CR-LR) difference technique for retrospective radon exposure assessments, since measurements of the 238U and 232Th concentrations in the relatively small real-life glass samples will make the retrospective radon exposure assessments impractical.

  18. 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.

  19. A study of radon emitted from building materials using plastic alpha-track detectors.

    PubMed

    Abu-Jarad, F; Fremlin, J H; Bull, R

    1980-07-01

    Films made from cellulose nitrate LR-115 (Pathé Kodak) and CR-39 have been used for long-term measurements of the radon-222 emanation from building materials and the resultant activity inside houses. The emanation from crushed granite bricks is found to be produced from within the brick while in the clay bricks it originates in the surface layers only. The airborne radon activity inside houses constructed from clay brick is found on average to be 22 mBq 1-1 (0.57 pCi 1-1) while inside a closed vessel sealed to the brick the average equilibrium activity is 40 mBq 1-1 pCi 1-1).

  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%.

  1. Low-Cost Radon Reduction Pilot Study

    SciTech Connect

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

    2015-09-01

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

  2. The Japanese Radon and Thoron Reference Chambers

    SciTech Connect

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

    2008-08-07

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

  3. 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

  4. Radon emanation on the San Andreas Fault

    USGS Publications Warehouse

    King, C. Y.

    1978-01-01

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

  5. Estimated effective dose rates from radon exposure in workplaces and residences within Los Alamos county in New Mexico

    SciTech Connect

    Whicker, Jeffrey J; Mcnaughton, Michael

    2009-01-01

    Many millions of office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the workplace are lacking. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were then used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about nine times greater exposure at home than while in the office (691 mrem yr{sup -1} versus 78 mrem yr{sup -1}). The estimated effective dose rate for a more homebound person was 896 mrem yr{sup -1}. These effective dose rates are contrasted against the 100 mrem yr{sup -1} threshold for regulation of a 'radiological worker' defined in the Department of Energy regulations occupational exposure and the 10 mrem yr{sup -1} air pathway effective public dose limit regulated by the Environmental Protection Agency.

  6. Study of Natural Radioactivity, Radon Exhalation Rate and Radiation Doses in Coal and Flyash Samples from Thermal Power Plants, India

    NASA Astrophysics Data System (ADS)

    Singh, Lalit Mohan; Kumar, Mukesh; Sahoo, B. K.; Sapra, B. K.; Kumar, Rajesh

    Coal is one of the most important source used for electrical power generation. Its combustion part known as fly ash is used in the manufacturing of bricks, sheets, cement, land filling etc. Coal and its by-products have significant amounts of radionuclide's including uranium, thorium which is the ultimate source of the radioactive gas radon and thoron respectively. Radiation hazard from airborne emissions of coal-fired power plants have been cited as possible causes of health in environmental. Assessment of the radiation exposure from coal burning is critically dependent on the concentration of radioactive elements in coal and in the fly ash. In the present study, samples of coal and flyash were collected from Rajghat Power Plant and Badarpur Thermal Power Plant, New Delhi, India. Radon exhalation is important parameter for the estimation of radiation risk from various materials. Solis State Nuclear Track Detector based sealed Can Technique (using LR-115 type II) has been used for measurement radon exhalation rate. Also accumulation chamber based Continuous Radon Monitor and Continuous Thoron Monitor have been used for radon masss exhalation and thoron surface exhalation rate respectively. Natural radioactivity has been measured using a low level NaI(Tl) detector based on gamma ray spectrometry.

  7. Biokinetic models for radiocesium and its progeny

    SciTech Connect

    Leggett, Richard Wayne

    2013-01-01

    Over the next few years the International Commission on Radiological Protection (ICRP) will publish a series of reports containing updated biokinetic and dosimetric models and dose coefficients for occupational intake of radionuclides. The biokinetic modeling scheme continues a trend in modern ICRP reports toward physiologically realistic descriptions of the time-dependent behavior of absorbed radionuclides and ingrowing chain members. This paper proposes systemic biokinetic models for cesium isotopes and their chain members for use in these ICRP reports and examines dosimetric implications of the proposed models. Comparisons of A = tissue dose per unit input to blood based on current ICRP models for workers (ICRP Publication 68, 1994) with B = corresponding values based on the proposed biokinetic models (but using dosimetry models of Publication 68) yields the following ranges of ratios B:A for tissues addressed in current ICRP documents: 0.5-25 for 130Cs (T1/2 = 29.2 min), 0.6-9.5 for 134mCs (2.9 h), 0.8-2.2 for 129Cs (32.1 h), 0.7-1.7 for 131Cs (9.69 d), 0.8-1.3 for 136Cs (13.2 d), 0.7-1.1 for 134Cs (2.06 y), 0.5-1.9 for 137Cs (30.2 y), and 0.2-3.7 for 135Cs (2.3x106 y). The large differences in estimated tissue dose for some tissues and cesium isotopes, particularly short-lived isotopes, result mainly from differences in model predictions of the time-dependent distributions of cesium in the body. For example, the proposed and current ICRP models for cesium predict peak kidney contents of ~22% and ~0.4%, respectively, following intravenous injection of stable cesium. Based on the proposed models for cesium and its progeny, the only dosimetrically significant chain members of cesium isotopes are 137mBa, which represents 32-85% of the estimated tissue doses from injected 137Cs, and 134Cs, which represents 4-53% of the estimated tissue doses from injected 134mCs.

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

    SciTech Connect

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

    2008-08-07

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

  9. Radiological characterisation and radon equilibrium factor in the outdoor air of a post-industrial urban area.

    PubMed

    Rozas, S; Idoeta, R; Alegría, N; Herranz, M

    2016-01-01

    The radiological characterisation of outdoor air is always a complicated task due to the several radioactive emissions coming from the different radionuclides and also because of the very short half-lives of radionuclides in the natural radioactive series. In some places, this characterisation could result in unusual values because the natural presence of radionuclides with terrestrial origin can be modified by manmade activities. Nonetheless, this characterisation is useful not only for air quality control purposes but also because radon and its progeny in the outdoor air are the main contributors to human exposure from natural sources. In this study, we have carried out air particle sampling, followed by gamma-ray spectrometry, alpha spectrometry and beta counting determinations for this purpose. Subsequently, the outdoor air has been radiologically characterised through the obtained data and using a pre-existing analytical method to take into account the radioactive decays of short half-life radionuclides during sampling, sample preparation and measuring times. Bilbao was chosen to carry out this work. It is a medium-sized town located in northern Spain, close to the Atlantic Ocean and at sea level. This city has a recent industrial past as there were numerous steel mills and other heavy industries, including some quarries, and some open pit mines close to it, which concluded in a remediation program. So, it is a place where the air is potentially modified by manmade activities. The obtained results show that activity concentration values for long-lived radionuclides that precede radon and thoron are in the order of 10(-6) Bq m(-3) and long-lived ones after radon are around 10(-4) Bq m(-3). Thoron progeny are around 2 × 10(-2) Bq m(-3) and radon progeny are around 1.8 Bq m(-3). The mean radon equilibrium factor was 0.18. All of these values are close to the minimum UNSCEAR values, but show some variability, which highlights the importance of

  10. Radiological characterisation and radon equilibrium factor in the outdoor air of a post-industrial urban area.

    PubMed

    Rozas, S; Idoeta, R; Alegría, N; Herranz, M

    2016-01-01

    The radiological characterisation of outdoor air is always a complicated task due to the several radioactive emissions coming from the different radionuclides and also because of the very short half-lives of radionuclides in the natural radioactive series. In some places, this characterisation could result in unusual values because the natural presence of radionuclides with terrestrial origin can be modified by manmade activities. Nonetheless, this characterisation is useful not only for air quality control purposes but also because radon and its progeny in the outdoor air are the main contributors to human exposure from natural sources. In this study, we have carried out air particle sampling, followed by gamma-ray spectrometry, alpha spectrometry and beta counting determinations for this purpose. Subsequently, the outdoor air has been radiologically characterised through the obtained data and using a pre-existing analytical method to take into account the radioactive decays of short half-life radionuclides during sampling, sample preparation and measuring times. Bilbao was chosen to carry out this work. It is a medium-sized town located in northern Spain, close to the Atlantic Ocean and at sea level. This city has a recent industrial past as there were numerous steel mills and other heavy industries, including some quarries, and some open pit mines close to it, which concluded in a remediation program. So, it is a place where the air is potentially modified by manmade activities. The obtained results show that activity concentration values for long-lived radionuclides that precede radon and thoron are in the order of 10(-6) Bq m(-3) and long-lived ones after radon are around 10(-4) Bq m(-3). Thoron progeny are around 2 × 10(-2) Bq m(-3) and radon progeny are around 1.8 Bq m(-3). The mean radon equilibrium factor was 0.18. All of these values are close to the minimum UNSCEAR values, but show some variability, which highlights the importance of

  11. Radon as an Anthropogenic Indoor Air Pollutant

    NASA Astrophysics Data System (ADS)

    Gillmore, Gavin; Crockett, Robin

    2016-04-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

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

    USGS Publications Warehouse

    Reimer, G.M.

    1992-01-01

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

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

    PubMed

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

    2014-11-01

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

  15. Measurement of potential alpha energy exposure and potential alpha energy concentration and estimating radiation dose of radon in Sari city in the north region of Iran.

    PubMed

    Rahimi, Seyed Ali; Nikpour, Behzad

    2014-12-01

    In dwellings in Sari city in the northern region of Iran, the potential alpha energy exposure (PAEE) and potential alpha energy concentration (PAEC) have been measured and the radiation dose due to radon and its progenies has been estimated. In this study, the dosemeters DOSEman and SARAD GmbH (Germany), which are sensitive to alpha particles, were used. The population of the city of Sari is 495,369 people and the density of population is 116.5 people per km(2). A percentage of the total household population of Sari in areas of geographically different samples was selected. The PAEE, PAEC and radon concentration in four different seasons in a year in homes for sampling were measured. The mean PAEE due to indoor radon in homes of four cities in Sari city was estimated to be 28.23 Bq m(-3) and the mean PAEC was estimated to be 27.11 Bq m(-3). Also the mean indoor radon level was found to be 29.95 Bq m(-3). The annual dose equivalent is ∼0.0151 μSv y(-1). Measurement results show that the average PAEE, PAEC and radon concentration are higher in winter than in other seasons. This difference could be due to stillness and lack of air movement indoors in winter.

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

    PubMed

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

    2013-12-01

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

  17. Assigning linkage haplotypes from parent and progeny genotypes

    SciTech Connect

    Nejati-Javaremi, A.; Smith, C.

    1996-04-01

    Given the genotypes of parents and progeny, their haplotypes over several or many linked loci can be easily assigned by listing the allele type at each locus along the haplotype known to be from each parent. Only a small number (5-10) of progeny per family is usually needed to assign the parental and progeny haplotypes. Any gaps left in the haplotypes may be filled in from the assigned haplotypes of relatives. The process is facilitated by having multiple alleles at the loci and by using more linked loci in the haplotype and with more progeny from the mating. Crossover haplotypes in the progeny can be identified by their being unique or uncommon, and the crossover point can often be detected if the locus linkage map order is known. The haplotyping method applies to outbreeding populations in plants, animals, and man, as well as to traditional experimental crosses of inbred lines. The method also applies to half-sib families, whether the genotype of the mates are known or unknown. The haplotyping procedure is already used in linkage analysis but does not seem to have been published. It should be useful in teaching and in genetic applications of haplotypes. 15 refs., 5 tabs.

  18. Estimating lung cancer mortality from residential radon using data for low exposures of miners

    SciTech Connect

    Lubin, J.H.; Tomasek, L.; Kunz, E.

    1997-02-01

    Some recent estimates of lung cancer risk from exposure to radon progeny in homes have been based on models developed from a pooled analysis of 11 cohorts of underground miners exposed to radon. While some miners were exposed to over 10,000 working level months (WLM), mean exposure among exposed miners was 162 WLM, about 10 times the exposure from lifetime residence in an average house and about three times the exposure from lifetime residence at the {open_quotes}action level{close_quotes} suggested by the U.S. Environmental Protection Agency. The extrapolation of lung cancer risk from the higher exposures in the miners to the generally lower exposures in the home is a substantial source of uncertainty in the assessment of the risk of indoor radon. Using the pooled data for the miners, analyses of lung cancer risk were carried out on data restricted to lower exposures, either <50 WLM or <100 WLM. In the pooled data, there were 115 lung cancer cases among workers with no occupational WLM exposure and 2,674 among exposed miners, with 353 and 562 lung cancer cases in miners with <50 WLM and <100 WLM, respectively. Relative risks (RRs) for categories of WLM based on deciles exhibited a statistically significant increasing trend with exposure in each of the restricted data sets. In the restricted data, there was little evidence of departures from a linear excess relative risk model in cumulative exposure, although power to assess alternative exposure-response trends was limited. Risk models based on the unrestricted data for miners provided an excellent fit to the restricted data, suggesting substantial internal validity in the projection of risk from miners with high exposures to those with low exposures. Estimates of attributable risk for lung cancer (10-14%) in the U.S. from residential radon based on models from the unrestricted data were similar to estimates based on the data for miners receiving low exposures. 34 refs., 2 figs., 7 tabs.

  19. TEST CELL STUDIES OF RADON ENTRY

    EPA Science Inventory

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

  20. Exposure to unusually high indoor radon levels

    SciTech Connect

    Rasheed, F.N. )

    1993-03-27

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

  1. Modeling of radon transport in unsaturated soil

    SciTech Connect

    Chen, C.; Thomas, D.M.; Green, R.

    1995-08-10

    This study applies a recently developed model, LEACHV, to simulate transport of radon through unsaturated soil and compares calculated soil radon activities against field-measured values. For volatile and gas phase transport, LEACHV is modified from LEACHP, a pesticide version of LEACHM, as well-documented one-dimensional model for water and chemical movement through unsaturated soil. LEACHV adds consideration of air temperature changes and air flow driven by barometric pressure change to the other soil variables currently used in LEACHP. It applies diurnal barometric pressure and air temperature changes to reflect more accurately the typical field conditions, Sensitivity analysis and simulated results have clearly demonstrated the relative importance of barometric pressure change, rainfall events, changes in water content, gas advection, and radon source term in radon transport process. Comparisons among simulated results illustrated that the importance of barometric pressure change and its pumping phenomenon produces both fluctuation in soil gas radon activities and an elevation of the long-term average radon activity in shallow soils of an equal magnitude to the disturbed source parameter. Comparisons between measured and simulated soil radon activities showed that LEACHV can provide realistic estimates of radon activity concentration in the soil profile. 41 refs., 10 figs., 2 tabs.

  2. Wavelet analysis of radon time series

    NASA Astrophysics Data System (ADS)

    Barbosa, Susana; Pereira, Alcides; Neves, Luis

    2013-04-01

    Radon is a radioactive noble gas with a half-life of 3.8 days ubiquitous in both natural and indoor environments. Being produced in uranium-bearing materials by decay from radium, radon can be easily and accurately measured by nuclear methods, making it an ideal proxy for time-varying geophysical processes. Radon time series exhibit a complex temporal structure and large variability on multiple scales. Wavelets are therefore particularly suitable for the analysis on a scale-by-scale basis of time series of radon concentrations. In this study continuous and discrete wavelet analysis is applied to describe the variability structure of hourly radon time series acquired both indoors and on a granite site in central Portugal. A multi-resolution decomposition is performed for extraction of sub-series associated to specific scales. The high-frequency components are modeled in terms of stationary autoregressive / moving average (ARMA) processes. The amplitude and phase of the periodic components are estimated and tidal features of the signals are assessed. Residual radon concentrations (after removal of periodic components) are further examined and the wavelet spectrum is used for estimation of the corresponding Hurst exponent. The results for the several radon time series considered in the present study are very heterogeneous in terms of both high-frequency and long-term temporal structure indicating that radon concentrations are very site-specific and heavily influenced by local factors.

  3. Radon Risk Communication Strategies: A Regional Story.

    PubMed

    Cheng, Winnie

    2016-01-01

    Risk communication on the health effects of radon encounters many challenges and requires a variety of risk communication strategies and approaches. The concern over radon exposure and its health effects may vary according to people's level of knowledge and receptivity. Homeowners in radon-prone areas are usually more informed and have greater concern over those not living in radon-prone areas. The latter group is often found to be resistant to testing. In British Columbia as well as many other parts of the country, some homes have been lying outside of the radon-prone areas have radon levels above the Canadian guideline, which is the reason Health Canada recommends that all homes should be tested. Over the last five years, the Environment Health Program (EHP) of Health Canada in the British Columbia region has been using a variety of different approaches in their radon risk communications through social media, workshops, webinars, public forums, poster contests, radon distribution maps, public inquiries, tradeshows and conference events, and partnership with different jurisdictions and nongovernmental organizations. The valuable lessons learned from these approaches are discussed in this special report. PMID:26867298

  4. 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

  5. Removal of Radon from Household Water.

    ERIC Educational Resources Information Center

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

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

  6. Radon Measurements in Schools: An Interim Report.

    ERIC Educational Resources Information Center

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

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

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

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

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

  8. Radon Measurement in Schools. Revised Edition.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

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

  9. Radon Risk Communication Strategies: A Regional Story.

    PubMed

    Cheng, Winnie

    2016-01-01

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

  10. SITE-SPECIFIC MEASUREMENTS OF RESIDENTIAL RADON PROTECTION CATEGORY

    EPA Science Inventory

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

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

    ERIC Educational Resources Information Center

    Gundersen, Linda C. S.

    1992-01-01

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

  12. Radon risk perception and testing: Sociodemographic correlates

    SciTech Connect

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

    1994-03-01

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

  13. Radon: implications for the health professional

    SciTech Connect

    Romano, C.A.

    1990-01-01

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

  14. Indoor radon risk potential of Hawaii

    USGS Publications Warehouse

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

    2005-01-01

    A comprehensive evaluation of radon risk potential in the State of Hawaii indicates that the potential for Hawaii is low. Using a combination of factors including geology, soils, source-rock type, soil-gas radon concentrations, and indoor measurements throughout the state, a general model was developed that permits prediction for various regions in Hawaii. For the nearly 3,100 counties in the coterminous U.S., National Uranium Resource Evaluation (NURE) aerorad data was the primary input factor. However, NURE aerorad data was not collected in Hawaii, therefore, this study used geology and soil type as the primary and secondary components of potential prediction. Although the radon potential of some Hawaiian soils suggests moderate risk, most houses are built above ground level and the radon soil potential is effectively decoupled from the house. Only underground facilities or those with closed or recirculating ventilation systems might have elevated radon potential. ?? 2005 Akade??miai Kiado??.

  15. 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.

  16. Radon exposure and oropharyngeal cancer risk.

    PubMed

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

    2015-12-01

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

  17. Mars Airborne Prospecting Spectrometer

    NASA Astrophysics Data System (ADS)

    Steinkraus, J. M.; Wright, M. W.; Rheingans, B. E.; Steinkraus, D. E.; George, W. P.; Aljabri, A.; Hall, J. L.; Scott, D. C.

    2012-06-01

    One novel approach towards addressing the need for innovative instrumentation and investigation approaches is the integration of a suite of four spectrometer systems to form the Mars Airborne Prospecting Spectrometers (MAPS) for prospecting on Mars.

  18. 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.

  19. Indoor radon and lung cancer in China

    SciTech Connect

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

    1990-06-20

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

  20. Radon and the system of radiological protection.

    PubMed

    Lecomte, J F

    2012-01-01

    At its meeting in Porto, Portugal, in November 2009, the Main Commission of the International Commission on Radiological Protection (ICRP) approved the formation of a new Task Group, reporting to Committee 4, to develop guidance on radiological protection against radon exposure. This article describes the Task Group's draft report entitled "Radiological Protection against Radon Exposure" which has been posted on the ICRP website for public consultation between January and June 2012. In this report, the Commission provides updated guidance on radiological protection against radon exposure. The report was developed considering the recently consolidated ICRP general recommendations, the new scientific knowledge about radon risk, and the experience gained by many organisations and countries in the control of radon exposure. The report describes the characteristics of radon exposure, covering sources and transfer mechanisms, nature of the risk, exposure conditions, similarities with other existing exposure situations, and challenges to manage radon exposure. In order to control radon exposure, the Commission recommends an integrated approach that is focused as much as possible on the management of the building or location in which radon exposure occurs, regardless of the purpose of the building and the category of the occupants. This approach is based on the optimisation principle, and a graded approach according to the degree of responsibilities at stake, notably in workplaces, and the level of ambition of the national authorities. The report emphasises the importance of preventive actions, and provides recommendations on how to control radon exposure in workplaces when workers' exposure can reasonably be regarded as being the responsibility of the operating management. In such a case, workers' exposures are considered to be occupational, and are controlled using the corresponding requirements on the basis of the optimisation principle, and application, as appropriate

  1. Modeled atmospheric radon concentrations from uranium mines

    SciTech Connect

    Droppo, J.G.

    1985-04-01

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

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

    USGS Publications Warehouse

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

    1999-01-01

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

  3. 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.

  4. 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.

  5. Radon, smoking, and lung cancer: the need to refocus radon control policy.

    PubMed

    Lantz, Paula M; Mendez, David; Philbert, Martin A

    2013-03-01

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

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

    PubMed Central

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

    2013-01-01

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

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

    PubMed

    Cucoş Dinu, Alexandra; Cosma, Constantin; Dicu, Tiberius; Begy, Robert; Moldovan, Mircea; Papp, Botond; Niţă, Dan; Burghele, Bety; Sainz, Carlos

    2012-08-01

    A comprehensive radon survey has been carried out in Băiţa radon-prone area, Transylvania, Romania, in 4 localities (Băiţa, Nucet, Fînaţe, and Cîmpani) situated in the vicinity of former Romanian uranium mines. Indoor radon concentrations have been measured in 1128 ground floor rooms and cellars of 303 family houses by using CR-39 diffusion type radon detectors. The annual average of indoor radon concentration for Băiţa area was found to be 241±178 Bq m(-3), which is about two times higher than the average value of 126 Bq m(-3), computed for Romania. About 28% of investigated houses exceed the reference level of radon gas in dwellings of 300 Bq m(-3). The indoor radon measurements on each house have been carried out in several rooms simultaneously with the aim of obtaining a more detailed picture on the exposure to radon in the studied area. An analysis on the variability of radon levels among floors (floor-to-floor variation) and rooms (room-to-room variation) and also the influence of factors like the presence of cellar or the age of the building is presented. The coefficient of variation (CV) within ground floor rooms of the same house (room-to-room variation) ranged between 0.9 and 120.8%, with an arithmetic mean of 46.2%, a large variability among rooms within surveyed dwellings being clearly identified. The mean radon concentration in bedrooms without cellar was higher than in bedrooms above the cellar, the difference being statistically significant (t test, one tail, p<0.001, n=82). For houses built during 1960-1970 an increasing trend for radon levels was observed, but overall there was no significant difference in indoor radon concentrations by age of dwelling (one-way ANOVA test, p>0.05).

  8. Adversity before Conception Will Affect Adult Progeny in Rats

    ERIC Educational Resources Information Center

    Shachar-Dadon, Alice; Schulkin, Jay; Leshem, Micah

    2009-01-01

    The authors investigated whether adversity in a female, before she conceives, will influence the affective and social behavior of her progeny. Virgin female rats were either undisturbed (controls) or exposed to varied, unpredictable, stressors for 7 days (preconceptual stress [PCS]) and then either mated immediately after the end of the stress…

  9. Normal and seasonally amplified indoor radon levels

    SciTech Connect

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

    1995-01-01

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

  10. Indoor radon concentration forecasting in South Tyrol.

    PubMed

    Verdi, L; Weber, A; Stoppa, G

    2004-01-01

    In this paper a modern statistical technique of multivariate analysis is applied to an indoor radon concentration data base. Several parameters are more or less significant in determining the radon concentration inside a building. The elaboration of the information available on South Tyrol makes it possible both to identify the statistically significant variables and to build up a statistical model that allows us to forecast the radon concentration in dwellings, when the values of the same variables involved are given. The results confirm the complexity of the phenomenon.

  11. Radon program of the Czech Republic.

    PubMed

    Petrová, K; Pravdová, E

    2014-07-01

    The Radon Program of the Czech Republic 2010-2019--Action Plan is based on Governmental Decision No. 594/2009 (Radon Program of the Czech Republic 2010-2019--Action Plan, Government of the Czech Republic, Decision No. 594/2009, May 4 2009) and is coordinated by the State Office for Nuclear Safety. It covers both prevention in new house construction and intervention in existing houses with high indoor radon concentration. The Program is aimed at developing an effective public information system. It takes advantage of long-term experience and good scientific and technological background-staff, methods, standards and technologies.

  12. Soil gas radon assessment and development of a radon risk map in Bolsena, Central Italy.

    PubMed

    Cinelli, G; Tositti, L; Capaccioni, B; Brattich, E; Mostacci, D

    2015-04-01

    Vulsini Volcanic district in Northern Latium (Central Italy) is characterized by high natural radiation background resulting from the high concentrations of uranium, thorium and potassium in the volcanic products. In order to estimate the radon radiation risk, a series of soil gas radon measurements were carried out in Bolsena, the principal urban settlement in this area NE of Rome. Soil gas radon concentration ranges between 7 and 176 kBq/m(3) indicating a large degree of variability in the NORM content and behavior of the parent soil material related in particular to the occurrence of two different lithologies. Soil gas radon mapping confirmed the existence of two different areas: one along the shoreline of the Bolsena lake, characterized by low soil radon level, due to a prevailing alluvial lithology; another close to the Bolsena village with high soil radon level due to the presence of the high radioactive volcanic rocks of the Vulsini volcanic district. Radon risk assessment, based on soil gas radon and permeability data, results in a map where the alluvial area is characterized by a probability to be an area with high Radon Index lower than 20 %, while probabilities higher than 30 % and also above 50 % are found close to the Bolsena village.

  13. Application of the can technique and radon gas analyzer for radon exhalation measurements.

    PubMed

    Fazal-ur-Rehman; Al-Jarallah, M I; Musazay, M S; Abu-Jarad, F

    2003-01-01

    A passive "can technique" and an active radon gas analyzer with an emanation container were applied for radon exhalation rate measurements from different construction materials, viz. five marble seven ceramic and 100 granite tiles used in Saudi Arabia. The marble and ceramic tiles did not show detectable radon exhalation using the active radon gas analyzer system. However the granite tiles showed relatively high radon exhalations, indicating a relatively high uranium content. A comparison of the radon exhalation rates measured by the two techniques showed a linear correlation coefficient of 0.57. The radon exhalation rates from the granites varied from 0.02 to 6.58 Bqm(-2)h(-1) with an average of 1.35+/-1.40 Bqm(-2)h(-1). The geometric mean and the geometric standard deviation of the frequency distribution were found to be 0.80 and 3.1, respectively. The track density found on the nuclear track detectors in the can technique exposed to the granites, having high exhalation rates, varied linearly with exposure time with a linear correlation coefficient of 0.99. This experimental finding agrees with the theoretical prediction. The can technique showed sensitivity to low radon exhalation rates from ceramic, marble and some granite over a period of 2 months, which were not detectable by the active radon gas analyzer system. The reproducibility of data with both measuring techniques was found to be within a 7% deviation.

  14. 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

  15. 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

  16. National Radon Contractor Proficiency (RCP) Program. Proficiency report, June 1991

    SciTech Connect

    Not Available

    1991-06-01

    The primary objective of the U.S. Environmental Protection Agency's (EPA) efforts to address the indoor radon problem is to reduce radon levels in buildings throughout the country. Achieving the objective requires a nationwide supply of capable radon mitigation contractors. In the Indoor Radon Abatement Act of 1988, Congress authorized EPA to establish a program to evaluate radon mitigation contractors and to provide the information to the public in cooperation with the States. The Radon Contractor Proficiency (RCP) Program was developed to assist States, EPA Regions, local government officials, and the public in selecting contractors who have demonstrated their proficiency in reducing indoor radon levels. The program is managed by the EPA Office of Radiation Programs' Radon Division. Under the voluntary program, radon contractors demonstrate their proficiency by meeting specific Program requirements. Individual contractors who meet these requirements are then listed in periodic RCP Proficiency Reports.

  17. National radon contractor proficiency (RCP) program. Proficiency report, January 1993

    SciTech Connect

    Not Available

    1993-01-01

    The primary objective of the U.S. Environmental Protection Agency's (EPA) efforts to address the indoor radon problem is to reduce radon levels in buildings throughout the country. Achieving the objective requires a nationwide supply of capable radon mitigation contractors. In the Indoor Radon Abatement Act of 1988, Congress authorized EPA to establish a program to evaluate radon mitigation contractors and to provide the information to the public in cooperation with the States. The Radon Contractor Proficiency (RCP) Program was developed to assist States, EPA Regions, local government officials, and the public in selecting contractors who have demonstrated their proficiency in reducing indoor radon levels. The program is managed by the EPA Office of Radiation Programs' Radon Division. Under the voluntary program, radon contractors demonstrate their proficiency by meeting specific Program requirements. Individual contractors who meet these requirements are then listed in the Report.

  18. National Radon Contractor Proficiency (RCP) program. Proficiency report, September 1991

    SciTech Connect

    Not Available

    1991-09-01

    The primary objective of the U.S. Environmental Protection Agency's (EPA) efforts to address the indoor radon problem is to reduce radon levels in buildings throughout the country. Achieving this objective requires a nationwide supply of capable radon mitigation contractors. In the Indoor Radon Abatement Act of 1988, Congress authorized EPA to establish a program to evaluate radon mitigation contractors and to provide this information to the public in cooperation with the States. The Radon Contractor Proficiency (RCP) Program was developed to assist States, EPA Regions, local government officials, and the public in selecting contractors who have demonstrated their proficiency in reducing indoor radon levels. The program is managed by the EPA Office of Radiation Programs' Radon Division. Under this voluntary program, radon contractors demonstrate their proficiency by meeting specific Program requirements. Individual contractors who meet these requirements are then listed in the Report.

  19. National Radon Contractor Proficiency (RCP) program. Proficiency report, July 1992

    SciTech Connect

    Not Available

    1992-07-01

    The primary objective of the U.S. Environmental Protection Agency's (EPA) efforts to address the indoor radon problem is to reduce radon levels in buildings throughout the country. Achieving this objective requires a nationwide supply of capable radon mitigation contractors. In the Indoor Radon Abatement Act of 1988, Congress authorized EPA to establish a program to evaluate radon mitigation contractors and to provide this information to the public in cooperation with the States. The Radon Contractor Proficiency (RCP) Program was developed to assist States, EPA Regions, local government officials, and the public in selecting contractors who have demonstrated their proficiency in reducing indoor radon levels. This program is managed by the EPA Office of Radiation Programs' Radon Division. Under this voluntary program, radon contractors demonstrate their proficiency by meeting specific Program requirements. Individual contractors who meet these requirements are then listed in the Report.

  20. National Radon Contractor Proficiency (RCP) Program. Proficiency report, January 1992

    SciTech Connect

    Not Available

    1992-01-01

    The primary objective of the U.S. Environmental Protection Agency's (EPA) efforts to address the indoor radon problem is to reduce radon levels in buildings throughout the country. Achieving the objective requires a nationwide supply of capable radon mitigation contractors. In the Indoor Radon Abatement Act of 1988, Congress authorized EPA to establish a program to evaluate radon mitigation contractors and to provide the information to the public in cooperation with the States. The Radon Contractor Proficiency (RCP) Program was developed to assist States, EPA Regions, local government officials, and the public in selecting contractors who have demonstrated their proficiency in reducing indoor radon levels. The program is managed by the EPA Office of Radiation Programs' Radon Division. Under the voluntary program, radon contractors demonstrate their proficiency by meeting specific Program requirements. Individual contractors who meet these requirements are then listed in the Report.

  1. Radon and material radiopurity assessment for the NEXT double beta decay experiment

    SciTech Connect

    Cebrián, S.; Dafni, T.; González-Díaz, D.; Herrera, D. C.; Irastorza, I. G.; Luzón, G.; Ortiz de Solórzano, A.; Villar, J. A.; Álvarez, V.; Cárcel, S.; Cervera, A.; Díaz, J.; Ferrario, P.; Gómez-Cadenas, J. J.; Laing, A.; Liubarsky, I.; López-March, N. [Instituto de Física Corpuscular, CSIC & Universitat de València, C and others

    2015-08-17

    The ”Neutrino Experiment with a Xenon TPC” (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in {sup 136}Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes have been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too.

  2. Radon and material radiopurity assessment for the NEXT double beta decay experiment

    NASA Astrophysics Data System (ADS)

    Cebrián, S.; Pérez, J.; Bandac, I.; Labarga, L.; Álvarez, V.; Barrado, A. I.; Bettini, A.; Borges, F. I. G. M.; Camargo, M.; Cárcel, S.; Cervera, A.; Conde, C. A. N.; Conde, E.; Dafni, T.; Díaz, J.; Esteve, R.; Fernandes, L. M. P.; Fernández, M.; Ferrario, P.; Freitas, E. D. C.; Fernandes, L. M. P.; Gehman, V. M.; Goldschmidt, A.; Gómez-Cadenas, J. J.; González-Díaz, D.; Gutiérrez, R. M.; Hauptman, J.; Morata, J. A. Hernando; Herrera, D. C.; Irastorza, I. G.; Laing, A.; Liubarsky, I.; López-March, N.; Lorca, D.; Losada, M.; Luzón, G.; Marí, A.; Martín-Albo, J.; Martínez, A.; Martínez-Lema, G.; Miller, T.; Monrabal, F.; Monserrate, M.; Monteiro, C. M. B.; Mora, F. J.; Moutinho, L. M.; Vidal, J. Muñoz; Nebot-Guinot, M.; Nygren, D.; Oliveira, C. A. B.; de Solórzano, A. Ortiz; Aparicio, J. L. Pérez; Querol, M.; Renner, J.; Ripoll, L.; Rodríguez, J.; Santos, F. P.; dos Santos, J. M. F.; Serra, L.; Shuman, D.; Simón, A.; Sofka, C.; Sorel, M.; Toledo, J. F.; Torrent, J.; Tsamalaidze, Z.; Veloso, J. F. C. A.; Villar, J. A.; Webb, R. C.; White, J. T.; Yahlali, N.

    2015-08-01

    The "Neutrino Experiment with a Xenon TPC" (NEXT), intended to investigate the neutrinoless double beta decay using a high-pressure xenon gas TPC filled with Xe enriched in 136Xe at the Canfranc Underground Laboratory in Spain, requires ultra-low background conditions demanding an exhaustive control of material radiopurity and environmental radon levels. An extensive material screening process is underway for several years based mainly on gamma-ray spectroscopy using ultra-low background germanium detectors in Canfranc but also on mass spectrometry techniques like GDMS and ICPMS. Components from shielding, pressure vessel, electroluminescence and high voltage elements and energy and tracking readout planes have been analyzed, helping in the final design of the experiment and in the construction of the background model. The latest measurements carried out will be presented and the implication on NEXT of their results will be discussed. The commissioning of the NEW detector, as a first step towards NEXT, has started in Canfranc; in-situ measurements of airborne radon levels were taken there to optimize the system for radon mitigation and will be shown too.

  3. Radon exposure in the thermal spas of Lesvos Island--Greece.

    PubMed

    Vogiannis, E; Nikolopoulos, D; Louizi, A; Halvadakis, C P

    2004-01-01

    The aim of this work is to study the exposure due to radon to bathers and personnel in the spas of Lesvos Island under a specific use pattern. 222Rn concentrations in the supplying water were measured during a long time period. Variations in indoor 222Rn, attached and unattached progenies, and influence of the ambient atmosphere were thoroughly analysed during bath treatment for the purpose of investigating a consequent probable short-term health impact. Concentration peaks both for 222Rn and PAEC were found to appear during bathtubs filling. These peaks considered imposing an additional short-term radiation burden for spa users. The additional doses delivered to bathers during bath treatment were found to be very low and for personnel did not exceed the value of 5 mSv per year.

  4. Radon potential, geologic formations, and lung cancer risk

    PubMed Central

    Hahn, Ellen J.; Gokun, Yevgeniya; Andrews, William M.; Overfield, Bethany L.; Robertson, Heather; Wiggins, Amanda; Rayens, Mary Kay

    2015-01-01

    Objective Exposure to radon is associated with approximately 10% of U.S. lung cancer cases. Geologic rock units have varying concentrations of uranium, producing fluctuating amounts of radon. This exploratory study examined the spatial and statistical associations between radon values and geological formations to illustrate potential population-level lung cancer risk from radon exposure. Method This was a secondary data analysis of observed radon values collected in 1987 from homes (N = 309) in Kentucky and geologic rock formation data from the Kentucky Geological Survey. Radon value locations were plotted on digital geologic maps using ArcGIS and linked to specific geologic map units. Each map unit represented a package of different types of rock (e.g., limestone and/or shale). Log-transformed radon values and geologic formation categories were compared using one-way analysis of variance. Results Observed radon levels varied significantly by geologic formation category. Of the 14 geologic formation categories in north central Kentucky, four were associated with median radon levels, ranging from 8.10 to 2.75 pCi/L. Conclusion Radon potential maps that account for geologic factors and observed radon values may be superior to using observed radon values only. Knowing radon-prone areas could help target population-based lung cancer prevention interventions given the inequities that exist related to radon. PMID:26844090

  5. Airborne data acquisition techniques

    SciTech Connect

    Arro, A.A.

    1980-01-01

    The introduction of standards on acceptable procedures for assessing building heat loss has created a dilemma for the contractor performing airborne thermographic surveys. These standards impose specifications on instrumentation, data acquisition, recording, interpretation, and presentation. Under the standard, the contractor has both the obligation of compliance and the requirement of offering his services at a reasonable price. This paper discusses the various aspects of data acquisition for airborne thermographic surveys and various techniques to reduce the costs of this operation. These techniques include the calculation of flight parameters for economical data acquisition, the selection and use of maps for mission planning, and the use of meteorological forecasts for flight scheduling and the actual execution of the mission. The proper consideration of these factors will result in a cost effective data acquisition and will place the contractor in a very competitive position in offering airborne thermographic survey services.

  6. Attached, unattached fraction of progeny concentrations and equilibrium factor for dose assessments from (222)Rn and (220)Rn.

    PubMed

    Singh, Parminder; Saini, Komal; Mishra, Rosaline; Sahoo, Bijay Kumar; Bajwa, Bikramjit Singh

    2016-08-01

    In this study, measurements of indoor radon ((222)Rn), thoron ((220)Rn) and their equilibrium equivalent concentration (EEC) were carried out in 96 dwellings from 22 different villages situated in Hamirpur district, Himachal Pradesh, India, by using LR-115 type II-based pinhole twin cup dosimeters and deposition-based progeny sensors (DRPS/DTPS). The annual average indoor (222)Rn and (220)Rn concentrations observed in these dwellings were 63.82 and 89.59 Bq/m(3), respectively, while the average EEC (attached + unattached) for (222)Rn and (220)Rn was 29.28 and 2.74 Bq/m(3). For (222)Rn (f Rn) and (220)Rn (f Tn), the average values of unattached fraction were 0.11 and 0.09, respectively. The equilibrium factors for radon (F Rn) and thoron (F Tn) varied from 0.12 to 0.77 with an average of 0.50, and from 0.01 to 0.34 with an average of 0.05, respectively. The annual inhalation dose due to mouth and nasal breathing was calculated using dose conversion factors and unattached fractions. The indoor annual effective doses for (222)Rn (AEDR) and (220)Rn (AEDT) were found to be 1.92 and 0.83 mSv a(-1), respectively. The values of (222)Rn/(220)Rn concentrations and annual effective doses obtained in the present study are within the safe limits as recommended by the International Commission on Radiological Protection for indoor dwelling exposure conditions. PMID:27289385

  7. Attached, unattached fraction of progeny concentrations and equilibrium factor for dose assessments from (222)Rn and (220)Rn.

    PubMed

    Singh, Parminder; Saini, Komal; Mishra, Rosaline; Sahoo, Bijay Kumar; Bajwa, Bikramjit Singh

    2016-08-01

    In this study, measurements of indoor radon ((222)Rn), thoron ((220)Rn) and their equilibrium equivalent concentration (EEC) were carried out in 96 dwellings from 22 different villages situated in Hamirpur district, Himachal Pradesh, India, by using LR-115 type II-based pinhole twin cup dosimeters and deposition-based progeny sensors (DRPS/DTPS). The annual average indoor (222)Rn and (220)Rn concentrations observed in these dwellings were 63.82 and 89.59 Bq/m(3), respectively, while the average EEC (attached + unattached) for (222)Rn and (220)Rn was 29.28 and 2.74 Bq/m(3). For (222)Rn (f Rn) and (220)Rn (f Tn), the average values of unattached fraction were 0.11 and 0.09, respectively. The equilibrium factors for radon (F Rn) and thoron (F Tn) varied from 0.12 to 0.77 with an average of 0.50, and from 0.01 to 0.34 with an average of 0.05, respectively. The annual inhalation dose due to mouth and nasal breathing was calculated using dose conversion factors and unattached fractions. The indoor annual effective doses for (222)Rn (AEDR) and (220)Rn (AEDT) were found to be 1.92 and 0.83 mSv a(-1), respectively. The values of (222)Rn/(220)Rn concentrations and annual effective doses obtained in the present study are within the safe limits as recommended by the International Commission on Radiological Protection for indoor dwelling exposure conditions.

  8. Prokaryotic and eukaryotic airborne microorganisms as tracers of microclimatic changes in the underground (Postojna Cave, Slovenia).

    PubMed

    Mulec, Janez; Vaupotič, Janja; Walochnik, Julia

    2012-10-01

    Bioaerosols in cave air can serve as natural tracers and, together with physical parameters, give a detailed view of conditions in the cave atmosphere and responses to climatic changes. Airborne microbes in the Postojna Cave system indicated very dynamic atmospheric conditions, especially in the transitory seasonal periods between winter and summer. Physical parameters of cave atmosphere explained the highest variance in structure of microbial community in the winter and in the summer. The airborne microbial community is composed of different microbial groups with generally low abundances. At sites with elevated organic input, occasional high concentrations of bacteria and fungi can be expected of up to 1,000 colony-forming units/m(3) per individual group. The most abundant group of airborne amoebozoans were the mycetozoans. Along with movements of air masses, airborne algae also travel deep underground. In a cave passage with elevated radon concentration (up to 60 kBq/m(3)) airborne biota were less abundant; however, the concentration of DNA in the air was comparable to that in other parts of the cave. Due to seasonal natural air inflow, high concentrations of biological and inanimate particles are introduced underground. Sedimentation of airborne allochthonous material might represent an important and continuous source of organic material for cave fauna. PMID:22570119

  9. Optical detection of radon decay in air

    PubMed Central

    Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Toivonen, Harri; Toivonen, Juha

    2016-01-01

    An optical radon detection method is presented. Radon decay is directly measured by observing the secondary radiolumines cence light that alpha particles excite in air, and the selectivity of coincident photon detection is further enhanced with online pulse-shape analysis. The sensitivity of a demonstration device was 6.5 cps/Bq/l and the minimum detectable concentration was 12 Bq/m3 with a 1 h integration time. The presented technique paves the way for optical approaches in rapid radon detec tion, and it can be applied beyond radon to the analysis of any alpha-active sample which can be placed in the measurement chamber. PMID:26867800

  10. 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.

  11. Measuring radon source magnitude in residential buildings

    SciTech Connect

    Nazaroff, W.W.; Boegel, M.L.; Nero, A.V.

    1981-08-01

    A description is given of procedures used in residences for rapid grab-sample and time-dependent measurements of the air-exchange rate and radon concentration. The radon source magnitude is calculated from the results of simultaneous measurements of these parameters. Grab-sample measurements in three survey groups comprising 101 US houses showed the radon source magnitude to vary approximately log-normally with a geometric mean of 0.37 and a range of 0.01 to 6.0 pCi 1/sup -1/ h/sup -1/. Successive measurements in six houses in the northeastern United States showed considerable variability in source magnitude within a given house. In two of these houses the source magnitude showed a strong correlation with the air-exchange rate, suggesting that soil gas influx can be an important transport process for indoor radon.

  12. Optical detection of radon decay in air.

    PubMed

    Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Toivonen, Harri; Toivonen, Juha

    2016-02-12

    An optical radon detection method is presented. Radon decay is directly measured by observing the secondary radiolumines cence light that alpha particles excite in air, and the selectivity of coincident photon detection is further enhanced with online pulse-shape analysis. The sensitivity of a demonstration device was 6.5 cps/Bq/l and the minimum detectable concentration was 12 Bq/m(3) with a 1 h integration time. The presented technique paves the way for optical approaches in rapid radon detec tion, and it can be applied beyond radon to the analysis of any alpha-active sample which can be placed in the measurement chamber.

  13. 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.

  14. 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.

  15. Measurement of Radon in Indoor Air.

    ERIC Educational Resources Information Center

    Downey, Daniel M.; Simolunas, Glenn

    1988-01-01

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

  16. Radon in private drinking water wells.

    PubMed

    Otahal, P; Merta, J; Burian, I

    2014-07-01

    At least 10% of inhabitants in the Czech Republic are supplied with water from private sources (private wells, boreholes). With the increasing cost of water, the number of people using their own sources of drinking water will be likely to increase. According to the Decree of the State Office for Nuclear Safety about the Radiation Protection 307/2002 as amended by Decree 499/2005, the guideline limit for the supplied drinking water ('drinking water for public supply') for radon concentration is 50 Bq·l(-1). This guideline does not apply to private sources of drinking water. Radon in water influences human health by ingestion and also by inhalation when radon is released from water during showering and cooking. This paper presents results of measurements of radon concentrations in water from private wells in more than 300 cases. The gross concentration of alpha-emitting radionuclides and the concentrations of radium and uranium were also determined. PMID:24714110

  17. Indoor radon in the region of Brussels

    SciTech Connect

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

    1999-12-01

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

  18. Radon Transform and Light-Cone Distributions

    NASA Astrophysics Data System (ADS)

    Teryaev, O. V.

    2016-08-01

    The relevance of Radon transform for generalized and transverse momentum dependent parton distributions is discussed. The new application for conditional (fracture) parton distributions and dihadron fragmentation functions is suggested.

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

    PubMed

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

    2007-11-15

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

  20. Airborne oceanographic lidar system

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Specifications and preliminary design of an Airborne Oceanographic Lidar (AOL) system, which is to be constructed for installation and used on a NASA Wallops Flight Center (WFC) C-54 research aircraft, are reported. The AOL system is to provide an airborne facility for use by various government agencies to demonstrate the utility and practicality of hardware of this type in the wide area collection of oceanographic data on an operational basis. System measurement and performance requirements are presented, followed by a description of the conceptual system approach and the considerations attendant to its development. System performance calculations are addressed, and the system specifications and preliminary design are presented and discussed.